WO2025196183A1 - Polyglycol-based lubricant compositions - Google Patents

Abstract

The invention relates to a lubricant composition containing a) a base oil containing a1) at least one ethylene oxide homopolymer, a2) at least one ethylene oxide/propylene oxide copolymer.

Description

Lubricant compositions based on polyglycol

The invention relates to a lubricant composition with good tribological properties and its use for lubricating tribological systems, in particular gears and/or bearings.

State of the art

Lubricants are essential components of many industrial processes in which two or more surfaces move in close contact. The range of applications for lubricants is very broad and encompasses a wide variety of tribological systems.

Lubricants can be formulated as lubricating oils or lubricating greases. In addition to the lubricating oil, lubricating greases also contain one or more thickeners. Both lubricating oils and lubricating greases typically contain a variety of substances (e.g., additives, oils, auxiliary materials, polymers, and thickeners in the case of lubricating greases) to regulate the lubricating grease properties and adjust the lubricating effect on the component.

Lubricating greases are often used to lubricate bearings.

Bearings are machine elements used to guide components that move relative to one another. Machine elements are components that perform the same or similar functions in different machines and devices and are therefore always present in the same or similar form. Bearings can be differentiated according to the degree of freedom of possible movement: radial bearings, axial bearings, radial axis bearings, and linear bearings. Bearings can also be differentiated according to their operating principle. In linear bearings, the components moving relative to one another are in direct contact; in rolling bearings, the moving components do not touch directly but are separated by rolling elements. Rolling bearings can be roller bearings or ball bearings. Roller bearings can be needle bearings, cylindrical roller bearings, tapered roller bearings, and spherical roller bearings. Bearings are usually filled with lubricating grease during production, which is held in place in the bearing or guide by suitable sealing elements.

Industrial gearboxes are transmission systems specifically designed for industrial applications. They play a crucial role in the manufacturing industry, mining, power plants, and other sectors. Some important aspects of industrial gearboxes are: power and torque transmission. Industrial gearboxes are designed to transmit high power. They can be coupled with large motors and They handle enormous torques. Preferred gear types are spur gears, bevel gears, and/or planetary gears. Spur gears are robust and well-suited for high torques. They are commonly used in conveyor belts, mills, and cranes. Bevel gears transmit rotary motion between off-axis shafts. They are found in pumps, fans, and mixers. Planetary gears are compact gearboxes. They offer a high gear ratio and are used in robot arms, wind turbines, and printing presses.

WO2017210388 (A1) describes a lubricant composition comprising a polyalkylene glycol-based oil component in an amount of at least about 60 parts by weight, based on 100 parts by weight of the lubricant composition. The polyalkylene glycol-based oil component contains two polyalkylene glycols of different viscosities. The polyalkylene glycols are EO/PO copolymers.

US 6436883 B1 describes a liquid composition consisting essentially of: a) a water-soluble polyoxyalkylene glycol monobutyl ether having a molecular weight between 450 and 5000, wherein the polyoxyalkylene glycol monobutyl ether is derived from n-butanol and a gaseous mixture of ethylene oxide and propylene oxide, and wherein the viscosity of the polyoxyalkylene glycol monobutyl ether is between 100 and 4000 in Saybolt Universal Seconds at 38°C; b) a carboxylic acid having between 6 and 18 carbon atoms per carboxylic acid molecule; and c) an amine. The composition can be used as a hydraulic fluid or gear oil.

With increasing demands, there is a constant need for new lubricants with good tribological properties. These new lubricants should be characterized in particular by a low coefficient of friction over a wide temperature range, a broad sliding and rolling action, and low specific resistance.

Surprisingly, it has now been found that this task is solved by the use of special base oils containing selected polyglycols as base oils for lubricant compositions.

SUMMARY OF THE INVENTION

A first subject of the invention is a lubricant composition comprising a) a base oil containing a1) at least one ethylene oxide homopolymer, a2) at least one ethylene oxide/propylene oxide copolymer.

Optionally, the lubricant composition contains at least one additive b) and/or at least one thickener c).

In a specific embodiment, a lubricant composition according to the invention contains: a) a base oil containing a1) at least one ethylene oxide homopolymer, a2) at least one ethylene oxide/propylene oxide copolymer, a3) at least one base oil different from a1) and a2).

Optionally, the lubricant composition contains at least one additive b) and/or at least one thickener c).

A lubricant composition according to the invention preferably contains: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%, based on the total weight of the lubricant composition, base oil containing a1) 10 wt.% to 90 wt.%, preferably 15 wt.% to 80 wt.%, in particular

15 wt.% to 50 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, in particular

50% to 85% by weight, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, of at least one additive, c) optionally 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition, of at least one thickener.

The proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%.

A preferred embodiment of the invention is a lubricant composition formed as a lubricating oil, comprising a) a base oil comprising a1) at least one ethylene oxide homopolymer, a2) at least one ethylene oxide/propylene oxide copolymer, a3) optionally at least one base oil different from a1) and a2), b) optionally at least one additive.

The proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%.

A lubricant composition according to the invention designed as a lubricating oil preferably contains: a) 80 wt.% to 99 wt.%, preferably 85 wt.% to 98 wt.%, in particular 90

Wt.% to 98 wt.%, based on the total weight of the lubricant composition, base oil containing a1) 10 wt.% to 90 wt.%, preferably 15 wt.% to 80 wt.%, in particular

15 wt.% to 50 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, in particular

50 wt.% to 85 wt.%, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, of at least one additive.

A further preferred embodiment of the invention is a

Lubricant composition in the form of a lubricating grease. Lubricating greases contain at least one thickener c).

Preferably, a lubricant composition designed as a lubricating grease contains: a) a base oil containing a1) at least one ethylene oxide homopolymer, a2) at least one ethylene oxide/propylene oxide copolymer, a3) optionally at least one base oil different from a1) and a2), b) optionally at least one additive, c) at least one thickener.

The proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80% by weight, for example 80% by weight to 100% by weight, preferably 90% by weight to 100% by weight.

More preferably, a lubricant composition according to the invention designed as a lubricating grease contains: a) 50 wt.% to 97 wt.%, preferably 60 wt.% to 95 wt.%, even more preferably 70 wt.% to 93 wt.%, in particular 80 wt.% to 90 wt.%, based on the total weight of the lubricant composition, base oil containing a1) 10 wt.% to 90 wt.%, preferably 15 wt.% to 80 wt.%, in particular

15 wt.% to 50 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, in particular

50 wt.% to 85 wt.%, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, of at least one additive, c) 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition, of at least one thickener.

The proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together based on the total weight of the base oil is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%.

More preferably, the ethylene oxide homopolymer has a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol.

A further subject matter of the invention is the use of a lubricant composition according to one or more of the embodiments described above and below for lubricating tribological systems, preferably selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools, gears of work equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools and/or bearings of work equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed.

A further subject matter of the invention is a tribological system, preferably selected from gears and/or bearings, which contains a lubricant composition according to one or more of the embodiments described above and below.

DESCRIPTION OF THE INVENTION

The present invention relates to a lubricant composition comprising a) a base oil comprising a1) at least one ethylene oxide homopolymer, preferably having a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer, b) optionally at least one additive.

The lubricant composition is suitable for lubricating tribological systems.

A tribological system is, in general terms, a technical system that enables, influences, or prevents movement through contact. Its essential components are the pairs of active surfaces involved in a tribological load and the load collective acting on them. Typically, a tribological system comprises at least one base body that is in contact and moving relative to at least one counter-body. The load collective includes the load applied to the bodies as well as the movement conditions, the friction state, and the temperature. An intermediate substance is often located between the two bodies; this can be lubricants specifically introduced to reduce wear.

In the context of the invention, a tribological system specifically refers to a system in which friction arises as a result of the relative movement of interacting surfaces. Lubricants are used to minimize wear caused by the stress on the surfaces as a result of friction. Lubricants reduce wear and ensure the function of parts subject to frictional forces. Preferred tribological systems for use with the lubricant compositions according to the invention are gears and/or bearings. Preferred gears are industrial gears, gears in electric vehicles, gears that are components of power tools, and/or gears of equipment for processing food, luxury goods, cosmetics, pharmaceuticals, and/or animal feed. Preferred bearings are bearings in industrial plants, bearings in vehicles such as automobiles, bearings that are components of power tools, and/or bearings of equipment for processing food, luxury goods, cosmetics, pharmaceuticals, and/or animal feed.

The lubricant compositions according to the invention have the following advantages:

They have very good tribological properties.

They have a very low coefficient of friction over a wide temperature range and a wide sliding and rolling component.

They have a low specific resistance. Surprisingly, they have lower friction values than lubricant compositions containing only EO/PO copolymers.

They enable a sufficient lubricating film thickness.

The lubricant compositions according to the invention comprise a base oil a) and optionally at least one additive b) and/or at least one thickener c). In a preferred embodiment, the proportion of the at least one additive b) is 0 wt.% to 15 wt.% and/or the proportion of the at least one thickener c) is 0 wt.% to 45 wt.%, in each case based on the total weight of the lubricant composition.

The base oil a) contains the at least one ethylene oxide homopolymer a1) and the at least one ethylene oxide/propylene oxide copolymer a2). The ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) are preferably base oils. Base oils are liquid at room temperature (20°C) and atmospheric pressure of 1013 hPa. Preferably, the proportion of the at least one ethylene oxide homopolymer a1) and the at least one ethylene oxide/propylene oxide copolymer a2) is each at least 2 wt.%, based on the total weight of the lubricant composition. a1) Ethylene oxide homopolymer a1)

The base oil of the lubricant composition according to the invention comprises at least one ethylene oxide homopolymer a1).

The ethylene oxide homopolymer a1) can be prepared in various ways, for example, starting from ethylene oxide as a monomer. Thus, the ethylene oxide homopolymer a1) can be prepared in a known manner by an anionic polymerization process in which ethylene oxide is combined with an initiator compound and a strongly basic catalyst, such as potassium hydroxide or organic amines.

The initiator compound contains one or more etherifiable groups, such as hydroxyl or ether groups. The initiator compound can be monofunctional or polyfunctional. The ethylene oxide homopolymer a1) is preferably prepared starting from an initiator compound selected from water, C1-6 monoalcohols, preferably C1-6 monoalcohols, for example methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 1-t-butoxy-2-propanol, 2-methyl-2-propanol, and C1-10 polyols, preferably ethylene glycol, propylene glycol, in particular 1,2-propanediol, glycerol, 1,1,1-trimethylolpropane, 1,1,1-trimethylolethane, 1,2,3-trihydroxybutane, pentaerythritol, xylitol, Arabitol, mannitol, sucrose, sorbitol, alkyl glucosides such as methyl glucoside and ethyl glucoside and mixtures thereof.

Water is classified as a monofunctional initiator because it possesses only one functional group (a hydroxy group, OH). This functional group enables the initiation of the polymerization of alkylene oxides.

The ethylene oxide homopolymer a1) is particularly preferably prepared starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, even more preferably water and/or C« monoalcohol, in particular water, methanol and mixtures thereof.

The ethylene oxide homopolymer a1) is particularly preferably prepared starting from ethylene oxide and/or ethylene glycol, preferably ethylene oxide, as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, even more preferably water and/or C« monoalcohol, in particular water, methanol and mixtures thereof.

Ethylene oxide homopolymer a1) can also be produced in other ways. For example, ethylene glycol can be used, which can be polymerized with alkyl halides or alkyl sulfates under basic conditions. Ethylene oxide homopolymer a1) can also be produced by reacting ethylene glycol with ether, such as dimethyl ether. "Ethylene oxide homopolymer" is the common term for polymers that contain one or more chains of oxyethylene groups. Ethylene oxide homopolymer a1) is therefore not limited to being produced from ethylene oxide.

The ethylene oxide homopolymer a1) contains one or more chains of oxyethylene groups. These are preferably bonded to an initiator compound via a heteroatom. Preferably, the ethylene oxide homopolymer a1) contains only one chain of oxyethylene groups, which are bonded to the initiator compound via a heteroatom. The heteroatom is preferably oxygen and is most preferably an ether bond.

The initiator compound can determine the terminal groups of the ethylene oxide homopolymer a1). The terminal groups can thus be introduced during the preparation of the ethylene oxide homopolymer a1). Alternatively or additionally, terminal Groups starting from an ethylene oxide homopolymer terminated with hydrogens are introduced by etherification reactions.

If a multifunctional initiator compound is used, two or more chains of oxyethylene groups of the ethylene oxide homopolymer a1) can be linked via the multifunctional initiator compound as a bridging group. In one embodiment, the ethylene oxide homopolymer a1) is prepared starting from monomeric ethylene oxide and/or monomeric ethylene glycol, preferably ethylene oxide, which has been reacted with an initiator compound selected from monofunctional initiator compounds, multifunctional initiator compounds, or mixtures thereof. In a preferred embodiment, the ethylene oxide homopolymer a1) is prepared starting from monomeric ethylene oxide which has been reacted with a monofunctional initiator compound.

Thus, multifunctional initiator compounds can determine bridging groups of the ethylene oxide homopolymer a1). Alternatively or additionally, bridging groups can be introduced by etherification reactions starting from a hydrogen-terminated ethylene oxide homopolymer.

The ethylene oxide homopolymer a1) preferably has terminal or bridging groups selected from hydrogen, C1-6 alkyl groups, preferably C« alkyl groups, C2-4 alkanediyl groups, Cs-e alkanetriyl groups and/or Cs-s alkanetetrayl groups.

The ethylene oxide homopolymer a1) particularly preferably has terminal hydrogens and/or terminal C1-6 alkyl groups, even more preferably terminal hydrogens and/or terminal C1-4 alkyl groups. In a very particularly preferred embodiment, the ethylene oxide homopolymer a1) has terminal hydrogens and/or terminal methyl groups.

The ethylene oxide homopolymer a1) is preferably an ethylene oxide homopolymer prepared with water, C1-6 monoalcohol, preferably C1-4 monoalcohol, in particular methanol, C2-4 dialcohol, C2-4 trialcohol, and/or C2-4 tetraalcohol as the initiator compound. Suitable C1-6 monoalcohols are, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 1-t-butoxy-2-propanol, and 2-methyl-2-propanol. A particularly preferred C1-6 monoalcohol is methanol. Particularly preferably, the ethylene oxide homopolymer a1) is an ethylene oxide homopolymer prepared with water and/or C1-6 monoalcohol, preferably C1-4 monoalcohol, in particular methanol, as initiator compound.

In a preferred embodiment, the ethylene oxide homopolymer a1) contains only one chain of oxyethylene groups. Even more preferably, the ethylene oxide homopolymer a1) contains only one chain of oxyethylene groups and has terminal hydrogens at both ends.

The ethylene oxide homopolymer a1) can be an uncapped, monocapped, digecapped, tricapped, or tetracapped homopolymer, or mixtures thereof. "Uncapped" means that all terminal groups are hydrogen; "monocapped" means that one terminal group is an alkyl radical, preferably C1-6 alkyl, more preferably C1-4 alkyl; "digecapped" means that two terminal groups are alkyl radicals, preferably C1-6 alkyl, more preferably C1-4 alkyl; "tricapped" means that three terminal groups are alkyl radicals, preferably C1-6 alkyl, more preferably C1-4 alkyl; and "tetracapped" means that four terminal groups are alkyl radicals, preferably C1-6 alkyl, more preferably C1-4 alkyl.

The determination of how many and which capping groups are present is preferably carried out using ISO 19929:2017.

In a preferred embodiment, the ethylene oxide homopolymer a1) is an uncapped, monocapped, or digecapped homopolymer, or a mixture thereof. Particularly preferably, the ethylene oxide homopolymer a1) is an uncapped or digecapped homopolymer, or a mixture thereof.

In a preferred embodiment, the ethylene oxide homopolymer is a compound of the general formula (I) wherein

R ^a is selected from H, C1-6 alkyl, preferably C1-4 alkyl, C2-4 alkanediyl groups, C3-6

Alkanetriyl groups and Cs-salkanetetrayl groups,

R ^b is selected from H, C1-6 alkyl, preferably C1-4 alkyl, where if R ^a is a C2-4alkanediyl group, the ethylene oxide homopolymer contains 2 fragments when R ^a is a Cs-ealkanetriyl group, the ethylene oxide homopolymer 3 fragments when R ^a is a Cs-salkanetetrayl group, the ethylene oxide homopolymer fragments p = an integer from 3 to 20, preferably 4 to 14, in particular 5 to 10.

In a preferred embodiment, the ethylene oxide homopolymer is a compound of the general formula (I) wherein

R ^a and R ^b are independently selected from H, C1-6 alkyl, preferably C1-4

Alkyl, C2-4alkanediyl, Cs-ealkanetriyl groups and Cs-salkanetetrayl groups, p = an integer from 3 to 20, preferably 4 to 14, in particular 5 to 10.

Preferably, R ^a and R ^b are independently selected from H and C1-6 alkyl, more preferably from H and C1-4 alkyl, in particular from H and methyl.

In a preferred embodiment, the ethylene oxide homopolymer is a compound of the general formula (I) wherein

R ^a and R ^b are independently selected from H, C1-6 alkyl, p = an integer from 3 to 20, preferably 4 to 14, in particular 5 to 10.

The ethylene oxide homopolymer a1) preferably has a molecular weight Mn, measured according to DIN 55672-1:2016-03 using THF as the solvent and polystyrene as the calibration standard, of 150 g/mol to 550 g/mol, more preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol. The advantage of these molecular weights is that the lubricant composition exhibits particularly high stability, especially when stored at low temperatures, and that these ethylene oxide homopolymers exhibit very good miscibility with component a2). Furthermore, the production of the base oil is particularly energy-efficient.

The ethylene oxide homopolymer a1) preferably has a melting point, measured according to DIN EN ISO 11357-3:2018 at a heating rate of 10°K/min, of at most 20°C, for example, from -65°C to 20°C, more preferably of at most 10°C, for example, from -65°C to 10°C. Advantages of these melting points include high stability, good miscibility with component a2), and energy-efficient production of the base oil.

More preferably, the ethylene oxide homopolymer a1) has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 3 mm ² /s to 50 mm ² /s, preferably of 10 mm ² /s to 50 mm ² /s, even more preferably of 20 mm ² /s to 45 mm ² /s, in particular of 22 mm ² /s to 38 mm ² /s.

The ethylene oxide homopolymer a1) can, in principle, be prepared by organic chemistry synthesis methods known to those skilled in the art. Preparation starting from ethylene oxide as the monomer is preferred. Suitable solvents, temperatures, pressures, and other reaction conditions can be readily selected by a person skilled in the art. The starting materials are commercially available or can be readily prepared by a person skilled in the art. b1) Ethylene oxide/propylene oxide copolymer a2) The base oil of the lubricant composition according to the invention comprises at least one ethylene oxide/propylene oxide copolymer a2). The ethylene oxide/propylene oxide copolymer a2) is preferably a random copolymer.

The ethylene oxide/propylene oxide copolymer a2) can be prepared in various ways, for example starting from ethylene oxide and propylene oxide as monomers. Thus, the ethylene oxide/propylene oxide copolymer a2) can be prepared in a known manner by an anionic polymerization process in which ethylene oxide and propylene oxide are reacted with an initiator compound and a strongly basic catalyst, such as potassium hydroxide or organic amines. The ethylene oxide/propylene oxide copolymer a2) can also be prepared in other ways. For example, instead of ethylene oxide and propylene oxide, ethylene glycol and/or 1,2-propylene glycol can be used as monomers and polymerized with alkyl halides or alkyl sulfates under basic conditions.

The initiator compound contains one or more etherifiable groups, such as hydroxyl or ether groups. The initiator compound can be monofunctional or polyfunctional. The ethylene oxide/propylene oxide copolymer a2) is preferably prepared starting from an initiator compound selected from water, C1-6 monoalcohols, preferably C« monoalcohols, for example methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 1-t-butoxy-2-propanol, 2-methyl-2-propanol, and C1-10 polyols, preferably ethylene glycol, propylene glycol, in particular 1,2-propanediol, glycerol, 1,1,1-trimethylolpropane, 1,1,1-trimethylolethane, 1,2,3-trihydroxybutane, pentaerythritol, xylitol, arabitol, mannitol, sucrose, sorbitol, alkylglucosides, such as methylglucoside, ethylglucoside and mixtures thereof.

The ethylene oxide/propylene oxide copolymer a2) is particularly preferably prepared starting from an initiator compound selected from water, C1-6 monoalcohols, in particular butanol, C2-4 dialcohols, in particular 1,2-propanediol, 1,2-ethanediol, pentaerythritol, and mixtures thereof. The ethylene oxide/propylene oxide copolymer a2) is particularly preferably prepared starting from an initiator compound selected from water, butanol, 1,2-propanediol, 1,2-ethanediol, pentaerythritol, and mixtures thereof.

The initiator compound can be the terminal groups of the ethylene oxide/propylene oxide

Copolymer a2). The terminal groups can thus be used in the production of the Ethylene oxide-propylene oxide copolymers. Alternatively or additionally, the terminal groups can be introduced by etherification reactions of ethylene oxide/propylene oxide copolymers that have hydrogens as terminal groups.

In a preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) is prepared starting from monomeric ethylene oxide and monomeric propylene oxide which has been reacted with an initiator compound selected from monofunctional initiator compounds, polyfunctional initiator compounds or mixtures thereof.

When using a monofunctional initiator compound, an ethylene oxide/propylene oxide copolymer a2) can be obtained that has only one chain of oxyalkylene groups. When using a multifunctional initiator compound, two or more chains of oxyalkylene groups of the ethylene oxide/propylene oxide copolymer a2) can also be linked via a multifunctional initiator compound as a bridging group.

Multifunctional initiator compounds can thus determine bridging groups of the ethylene oxide/propylene oxide copolymer a2). Alternatively or additionally, bridging groups can be introduced by etherification reactions starting from an ethylene oxide/propylene oxide copolymer a2) terminated with hydrogen.

When using a multifunctional initiator compound, an ethylene oxide/propylene oxide copolymer a2) can be obtained which has several chains of oxyalkylene groups. The oxyalkylene groups are then linked to one another via a multifunctional initiator compound as a bridging group. In one embodiment, the ethylene oxide/propylene oxide copolymer a2) has at least one bridging group selected from saturated hydrocarbon groups, for example alkylene groups. In a further embodiment, the ethylene oxide/propylene oxide copolymer a2) has at least one bridging group selected from C2-4 alkanediyl, Cs-e alkanetriyl groups, and Cs-s alkanetetrayl groups. In a further embodiment, the ethylene oxide/propylene oxide copolymer a2) has at least one bridging group selected from 1,2-propanediol, 1,2-ethanediol, pentaerythritol, and mixtures thereof. In a preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) has terminal hydrogens, terminal C1-6 alkyl groups, preferably terminal C1-4 alkyl groups, bridging C2-4 alkanediyl groups, bridging Cs-e alkanetriyl groups and/or terminal Cs-s alkanetetrayl groups.

The ethylene oxide/propylene oxide copolymer a2) particularly preferably has terminal hydrogens, terminal C1-4 alkyl groups, bridging C2-4 alkanediyl groups, and/or bridging C8-salkanetetrayl groups. In a very particularly preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) has terminal hydrogens, terminal butyl groups, and/or terminal propanyl groups.

Preferably, at least 40 wt.%, for example 40 wt.% to 60 wt.%, of the terminal groups of the ethylene oxide/propylene oxide copolymer a2) are alkyl radicals, preferably C1-6 alkyl.

The ethylene oxide/propylene oxide copolymer a2) can be an uncapped, monocapped, digecapped, tricapped, or tetracapped copolymer, or mixtures thereof. In a preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) is an uncapped, monocapped, or digecapped copolymer, or mixtures thereof. Particularly preferably, the ethylene oxide/propylene oxide copolymer a2) is an uncapped or monocapped copolymer, or mixtures thereof.

In a preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) comprises at least one structural group of the general formula (II) wherein

R is selected from H and C1-6 alkyl, preferably from H and C1-4 alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary. In the structural group of general formula (II), the order of the repeating units is random, so that this group is a statistical copolymer group. R is preferably selected from H and C—M alkyl.

The structural group of general formula (II) is linked to a terminal group or a bridging group via the serpentine bond. This terminal or bridging group is not shown above. The structural group of general formula (II) can be linked to further structural groups of general formula (II) via the bridging group. The ethylene oxide/propylene oxide copolymer a2) preferably comprises 1 to 10, more preferably 1 to 4, structural groups of general formula (II).

Suitable terminal groups and bridging groups are described above and below.

In a preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) is a compound of the general formula (III) wherein

R ¹ and R ² are independently selected from H and C1-6 alkyl, preferably from H and C1-4 alkyl, m = 3 to 20, preferably 5 to 20, n = 4 to 85, preferably 5 to 20, wherein the order of the repeating units is arbitrary; or a compound of the general formula (IV) wherein

R ¹ and R ² are independently selected from H and C1-6 alkyl, preferably from H and Ci-4 alkyl,

R ³ and R ⁴ are independently selected from H and C1-6 alkyl, preferably from H and C1-4 alkyl, in particular from H and methyl, each m is independently 3 to 20, each n is independently 4 to 85, wherein the order of the repeating units is arbitrary; or a compound of the general formula (V) wherein

R ¹ , R ² , R ³ and R ⁴ are independently selected from H and C1-6 alkyl, preferably from H and C1-6 alkyl, in particular H, each m is independently 3 to 20, preferably 4 to 20, each n is independently 4 to 85, preferably 4 to 50, wherein the order of the repeating units is arbitrary. The order of the repeating units in the compounds of the general formulas (III), (IV) and (V) is arbitrary, so that these compounds are statistical copolymers.

For the purposes of the invention, the term "copolymer" refers to polymers composed of at least two different monomers, for example, two, three, four, or more different monomers (terpolymers, quaterpolymers, etc.). Preferably, however, the ethylene oxide/propylene oxide copolymer a2) is composed of only two different monomers. Thus, in a preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) has only oxyethylene repeat units and oxymethylethylene repeat units.

In a further preferred embodiment, the weight fraction of the oxyethylene repeat units in the ethylene oxide/propylene oxide copolymer a2), in each case based on the total weight of the ethylene oxide/propylene oxide copolymer a2), is at least 20 wt.%, for example 20 wt.% to 90 wt.%, preferably at least 30 wt.%, for example 30 wt.% to 80 wt.%, even more preferably at least 40 wt.%, for example 40 wt.% to 80 wt.%, in particular at least 50 wt.%, for example 50 wt.% to 80 wt.%.

In a further preferred embodiment, the weight fraction of the 1-oxymethylethylene repeat units in the ethylene oxide/propylene oxide copolymer a2), based in each case on the total weight of the ethylene oxide/propylene oxide copolymer a2), is preferably at least 10 wt.%, for example 10 wt.% to 80 wt.%, more preferably at least 20 wt.%, for example 20 wt.% to 70 wt.%, more preferably 20 wt.% to 60 wt.%, in particular 20 wt.% to 50 wt.%.

In a further preferred embodiment, the weight fraction of the oxyethylene repeating units and oxymethylethylene repeating units taken together in the ethylene oxide/propylene oxide copolymer a2), based on the total weight of the ethylene oxide/propylene oxide copolymer a2), is preferably at least 90 wt.%, for example 90 wt.% to 100 wt.%, more preferably at least 95 wt.%, for example 95 wt.% to 100 wt.%.

The ethylene oxide/propylene oxide copolymer a2) can contain oxyethylene repeating units and oxymethylethylene repeating units different Repeating units. However, the weight fraction of any repeating units other than oxyethylene repeating units and oxymethylethylene repeating units present is preferably less than 10% by weight, more preferably less than 5% by weight, based on the total weight of the ethylene oxide/propylene oxide copolymer a2).

In a particularly preferred embodiment, the ethylene oxide/propylene oxide copolymer a2) contains no repeating units other than oxyethylene repeating units and oxymethylethylene repeating units.

More preferably, the ethylene oxide/propylene oxide copolymer has a molecular weight Mn, measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard, of 500 g/mol to 25,000 g/mol, preferably of 1,500 g/mol to 25,000 g/mol. Molecular weights of at least 1,500 g/mol are particularly suitable for foodstuffs because of their favorable toxicological properties. Likewise preferably, the ethylene oxide/propylene oxide copolymer has a molecular weight Mn, measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard, of over 1,900 g/mol, for example, of over 1,900 g/mol to 25,000 g/mol, preferably of 2,000 g/mol to 25,000 g/mol. This is advantageous because it allows the viscosities of the lubricant composition to be set sufficiently high even when using low-viscosity homopolymer.

The ethylene oxide/propylene oxide copolymer preferably has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 10 mm ² /s to 25,000 mm ² /s, preferably from 15 mm ² /s to 17,000 mm ² /s, in particular from 40 mm ² /s to 20,000 mm ² /s. The ethylene oxide/propylene oxide copolymer also preferably has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of over 200 mm ² /s, for example from over 200 mm ² /s to 25,000 mm ² /s, preferably from 220 mm ² /s to 25,000 mm ² /s. This is also advantageous because the viscosities of the lubricant composition can be set sufficiently high even when using low-viscosity homopolymer.

The ethylene oxide/propylene oxide copolymer can, in principle, be prepared by organic chemistry synthesis methods known to those skilled in the art. Preparation starting from ethylene oxide and propylene oxide as monomers is preferred. Suitable solvents, temperatures, pressures, and other reaction conditions can be determined by can be readily selected by a person skilled in the art. The starting materials are commercially available or can be readily prepared by a person skilled in the art.

Lubricant compositions

The invention relates to a lubricant composition comprising a) a base oil comprising a1) at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer.

The term "base oil" or "base oil" corresponds to the usual meaning in the field of lubricants. Base oils or base oils contained in lubricant compositions are preferably oils that are liquid at room temperature (20°C) and atmospheric pressure of 1013 hPa. Base oils or base oils can be assigned to Groups I, II, II+, III, IV or V according to the classification of the American Petroleum Institute (API) [(API 1509, Appendix E, September 2011)] or mixtures thereof. According to the invention, water is preferably not a base oil. API Group I are mineral oils that consist, for example, of naphthenic or paraffin-based oils. If these mineral oils are chemically modified compared to API Group I oils, low in aromatics, low in sulfur, and have a low proportion of saturates and thus improved viscosity/temperature behavior, the oils are classified according to API Group II and III. API Group III also includes so-called gas-to-liquid oils, which are not produced from the refining of crude oil, but rather through the chemical conversion of natural gas. Group IV oils are polyalphaolefins. Base oils that are not classified in Groups I-IV are assigned to Group V. Ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) belong to Group V.

According to the invention, a linguistic distinction is made between "base oil" and "base oil" to clarify that the "base oil" according to the invention can contain several base oils and thus different chemical compound classes. The base oil contains According to the invention, components a1) and a2) are used as base oils and, if appropriate, additional base oils a3) different from a1) and a2).

The proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80 wt.%.

The ethylene oxide homopolymer preferably has a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol.

The lubricant composition further preferably contains at least one ethylene oxide homopolymer a1) with a molecular weight Mn measured according to DIN 55672-1:2016-03 using THF as solvent and polystyrene as calibration standard of 200 g/mol to 400 g/mol, in combination with at least one ethylene oxide/propylene oxide copolymer a2) with a molecular weight Mn measured according to DIN 55672-1:2016-03 using THF as solvent and polystyrene as calibration standard of 1500 g/mol to 25,000 g/mol. Polymers with a high molecular weight of 1500 g/mol to 25,000 g/mol are particularly suitable for use in lubricating equipment for processing food, luxury goods, cosmetics, pharmaceuticals, and/or animal feed, as they have favorable toxicological properties.

The lubricant composition also preferably contains at least one ethylene oxide homopolymer a1) having a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 22 to 38 mm ² /s in combination with at least one ethylene oxide/propylene oxide copolymer a2) having a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 1500 g/mol to 25 000 g/mol.

In a preferred embodiment, the base oil consists of a1) at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer, a3) optionally at least one base oil different from a1) and a2), wherein the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is at least 80 wt.%.

In a further preferred embodiment, the lubricant composition according to the invention consists of a) a base oil containing a1) at least one ethylene oxide homopolymer preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably from 200 g/mol to 500 g/mol, in particular from 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer, a3) optionally at least one base oil different from a1) and a2), b) optionally at least one additive, c) optionally at least one thickener.

More preferably, the proportion of the base oil, based on the total weight of the lubricant composition, is 50 wt.% to 99 wt.%, even more preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%.

Likewise preferably, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the base oil is 10 wt.% to 90 wt.%, more preferably 15 wt.% to 80 wt.%, in particular 15 wt.% to 50 wt.%. Likewise particularly preferably, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the base oil is 10 wt.% to 40 wt.%, more preferably 10 wt.% to 30 wt.%, in particular 10 wt.% to 24 wt.%. Practical tests have shown that using a lower proportion of ethylene oxide homopolymer a1), preferably at most 50 wt.%, based on the total weight of the base oil, results in a higher lubricating film thickness. A higher lubricating film thickness is advantageous because it can significantly reduce the risk of wear.

Likewise preferably, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the lubricant composition is from 5 wt.% to 45 wt.%, preferably from 8 wt.% to 40 wt.%, in particular from 8 wt.% to 25 wt.%. Likewise particularly preferably, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the lubricant composition is from 10 wt.% to 40 wt.%, even more preferably from 10 wt.% to 30 wt.%, in particular from 10 wt.% to 24 wt.%.

Likewise preferably, the proportion of the at least one ethylene oxide/propylene oxide copolymer a2) is in each case based on the total weight of the base oil from 10 wt.% to 90 wt.%, preferably from 20 wt.% to 85 wt.%, in particular from 50 wt.% to 85 wt.%. Likewise preferably, the proportion of the at least one ethylene oxide/propylene oxide copolymer a2) is in each case based on the total weight of the base oil from 76 wt.% to 85 wt.%.

Likewise preferably, the proportion of the at least one ethylene oxide/propylene oxide copolymer a2) based on the total weight of the lubricant composition is 5 wt.% to 45 wt.%, preferably 8 wt.% to 40 wt.%, in particular 8 wt.% to 25 wt.%.

Particularly preferably, the proportion of the at least one ethylene oxide/propylene oxide copolymer a2) based on the total weight of the lubricant composition is 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, even more preferably 50 wt.% to 85 wt.%, in particular 76 wt.% to 85 wt.%.

Also preferably, the proportion of base oil a), based on the total weight of the lubricant composition, is 50 wt.% to 99 wt.%, more preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the lubricant composition is 5 wt.% to 45 wt.%, preferably 8 wt.% to 40 wt.%, in particular 8 wt.% to 25 wt.%.

Likewise preferably, the proportion of the base oil a), based on the total weight of the lubricant composition, is 50 wt.% to 99 wt.%, more preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the base oil is 15 wt.% to 50 wt.%, and the proportion of the at least one ethylene oxide/propylene oxide copolymer a2) based on the total weight of the base oil is 50 wt.% to 85 wt.%.

In a further preferred embodiment, the proportion of the at least one ethylene oxide homopolymer a1) is 5 wt.% to 45 wt.%, based on the total weight of the lubricant composition, and the lubricant composition is not a lubricant composition consisting exclusively of 25 wt.% polyethylene glycol, based on the total weight of the lubricant composition, and 75 wt.%, based on the total weight of the lubricant composition, ethylene oxide/propylene oxide copolymer.

Likewise preferably, the proportion of the optionally present base oil a3) different from a1) and a2) is 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil. In a further preferred embodiment, the proportion of the at least one base oil (a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is 0 to 15 wt.%, based on the total weight of the base oil.

Likewise preferably, the proportion of the optionally present base oil a3) different from a1) and a2) is 1 wt.% to 8 wt.%, preferably 2.5 wt.% to 5 wt.%, based on the total weight of the lubricant composition. In a further preferred embodiment, the proportion of the at least one base oil (a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is 0 to 8 wt.%, based on the total weight of the lubricant composition. In a preferred embodiment, the lubricant composition contains at least one additive b). The at least one additive b) preferably meets at least one of the following conditions: the additive is solid at room temperature (20°C) and atmospheric pressure of 1013 hPa, and the proportion of the additive is less than 2 wt.%, based on the total weight of the lubricant composition.

Additive b) also preferably has a solubility in the base oil (20°C) of at least 0.1 wt.%. Solubility is present when the additive forms a homogeneous phase with the base oil. To determine solubility, the mixture of base oil and additive b) is preferably first heated to 100°C while stirring, followed by cooling. The test for the formation of a homogeneous phase is carried out after cooling to 20°C.

Preferably, the additive b) is selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof.

Likewise preferably, the proportion of the optionally present at least one additive b) is 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition. In a further preferred embodiment, the proportion of the optionally present at least one additive b) is 0 wt.% to 15 wt.%, based on the total weight of the lubricant composition.

In a preferred embodiment, the lubricant composition according to the invention contains no water or water only in a proportion of less than 10 wt.%, for example from 0 wt.% to 10 wt.%, preferably from 0.1 wt.% to 8 wt.%, in particular from 0.1 wt.% to 6 wt.%, based on the total weight of the lubricant composition, wherein the proportion of water is determined coulometrically according to Karl Fischer in accordance with DIN 51777:2016-08.

In addition to at least one ethylene oxide homopolymer a1) and at least one ethylene oxide/propylene oxide copolymer a2), the lubricant composition may contain at least one base oil different therefrom (= component a3).

TI A special lubricant composition therefore contains a) a base oil containing a1) at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer, a3) at least one base oil different from a1) and a2), b) optionally at least one additive, preferably selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction value modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof, c) optionally at least one thickener.

If present, the lubricant composition according to the invention contains the at least one further base oil (a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2), preferably in an amount of 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil. In a further preferred embodiment, the proportion of the at least one further base oil (a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is 0 to 15 wt.%, based on the total weight of the base oil.

If the lubricant composition contains at least one base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2), this is preferably selected from esters, ethers, excluding ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2), linear or branched perfluoropolyether oils (PFPE oils), synthetic hydrocarbons, mineral oils, untreated and chemically modified vegetable oils, Group III oils, gas to liquid (GTL) oils, reraffinates and recyclates, polyalphaolefins (PAO), silicone oils, polyisobutenes and mixtures thereof.

Preferably, the base oil other than the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is not water.

Preferably, the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is selected from esters, ethers, excluding ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2), and mixtures thereof.

The base oil a3) which is different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is particularly preferably selected from esters, ethers, with the exception of ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2), and mixtures thereof, with the concentrations of the components in the ternary mixture a1), a2) and a3) being such that the ratio [(100*3*proportion of ethylene oxide homopolymer a1)/(3*proportion of ethylene oxide/propylene oxide copolymer a2)+ (0.33*proportion of base oil a3)] does not exceed a value of 30, and in the case of esters as the base oil a3) is preferably in the range from 23 to 30.

Particularly preferably, the base oil a3) is selected from esters, polyglycols, excluding ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2), and mixtures thereof.

The base oil a3) is particularly preferably selected from esters, polyglycols, with the exception of ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2), and mixtures thereof, with the concentrations of the components in the ternary mixture a1), a2) and a3) being such that the ratio [(100*3*proportion of ethylene oxide homopolymer a1)/(3*proportion of ethylene oxide/propylene oxide copolymer a2)+ (0.33*proportion of base oil a3)] does not exceed a value of 30, and in the case of esters as base oil a3) is preferably in the range from 23 to 30.

Most preferably, the base oil a3) is selected from esters, propylene oxide homopolymers, propylene oxide/butylene oxide copolymers and mixtures thereof. The base oil a3) is particularly preferably selected from esters, propylene oxide homopolymers, propylene oxide/butylene oxide copolymers and mixtures thereof, wherein for the concentrations of the components in the ternary mixture a1), a2) and a3) the ratio [(100*3*proportion of ethylene oxide homopolymer a1)/(3*proportion of ethylene oxide/propylene oxide copolymer a2)+ (0.33*proportion of base oil a3)] does not exceed a value of 30, and in the case of esters as base oil a3) is preferably in the range from 23 to 30.

Preferred esters for the base oil a3) are selected from an aliphatic or aromatic di-, tri- or tetracarboxylic acid with one or more Cybis C22 alcohols present in admixture, esters of trimethylolpropane, pentaerythritol or dipentaerythritol with aliphatic Cybis C22 carboxylic acids, cis-dimer acid esters with Gy to C22 alcohols, as well as complex esters and estolides and mixtures thereof.

Particularly preferred esters for the base oil a3) are selected from pentaerythritol esters, dipentaerythritol esters, trimellitic acid esters, hemimellitic acid esters, pyromellitic acid esters, estolides, dimer acid esters, trimer acid esters, trimethylolpropane esters (TMP esters), neopentyl glycol esters, dicarboxylic acid esters and mixtures thereof.

Ethers for the base oil a3) do not include ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2). Preferred ethers for the base oil a3) are selected from polyphenyl ether, diaryl ether, triaryl ether, tetrahydrofuran (THF) polymers, polyglycols, excluding ethylene oxide homopolymers and ethylene oxide/propylene oxide copolymers, and mixtures thereof.

Particularly preferred ethers for the base oil a3) are polyglycols, excluding ethylene oxide homopolymers a1) and ethylene oxide/propylene oxide copolymers a2). Preferred polyglycols are polyglycol homopolymers, excluding ethylene oxide homopolymers, copolymers of ethylene oxide, excluding ethylene oxide/propylene oxide copolymers, and mixtures thereof. For the purposes of the invention, the term "copolymer" also refers to polymers composed of three, four, or more different monomers (terpolymers, quaterpolymers, etc.).

Suitable polyglycol homopolymers include polypropylene glycols, polybutylene glycols, polytetrahydrofurans, and mixtures thereof. Suitable copolymers include ethylene oxide/butylene oxide copolymers and propylene oxide/butylene oxide copolymers. The copolymers can be block copolymers or random copolymers. Particularly preferred polyglycol homopolymers are propylene oxide homopolymers.

Particularly preferred copolymers are propylene oxide/butylene oxide copolymers, preferably initiated with monoalcohols, in particular C4-C12 alcohols.

Linear or branched perfluoropolyether oils (PFPE oils) are also possible as base oils a3). Suitable perfluoropolyether oils are, for example, selected from perfluoropolyethers (PFPE) of the formula:

^RA -(O- _CF2 )v-(O-C2F4)w-(O-C3F6)x-(O-CFCF3)y-(O- _CF2CF (CF3)) ^zORB where ^RA and R ^B are identical or different and are selected from -CF3, -C2F5 and -C3F7, and v, w, x, y, z are integers from > 0 to 500. PFPE oils are sold, for example, under the brand names Aflunox®, Krytox®, Fomblin® and Demnum®.

Synthetic hydrocarbons, mineral oils and mixtures thereof are also possible as base oils a3).

Group III oils are possible as base oils a3). Group III oils (hydrocracked synthetic oils) are synthetic hydrocarbons derived from petroleum base oils, produced entirely by hydrocracking, hydroisomerization, and hydrodesulfurization. They have a minimum of 90 percent saturates and a maximum of 0.03 percent sulfur, as well as a viscosity index of at least 120.

GTL oils (gas-to-liquids oils) are also advantageous as base oils a3). GTL oils are based on synthesis gas consisting of hydrogen and carbon monoxide, from which longer-chain hydrocarbons are produced using Fischer-Tropsch synthesis.

Polyalphaolefins (PAO) are also advantageously suitable as base oils a3). Polyalphaolefins are also referred to as Group IV oils and generally have a viscosity index in the range of 125 to 200. Polyalphaolefins can be produced catalytically from ethylene using known processes, initially yielding alphaolefins with longer chain lengths as intermediates. From these, the polyalphaolefins are essentially synthesized by oligomerization, usually resulting in isoparaffins with a varying number of equally long side chains. The synthesis can be carried out by acid-catalyzed (conventional) or metallocene-catalyzed olefin polymerization. (mPAO). Conventional PAOs exhibit a high degree of isomerization, whereas metallocene oligomerization results in products that are essentially free of isomerization. Suitable polyalphaolefins include, for example, the oligomers, preferably the dimers, trimers, tetramers, pentamers, and higher oligomers with more than 5 repeat units of alpha-olefins, and mixtures of these oligomers. The alpha-olefins used to prepare the polyalphaolefins are preferably selected from C8-C14 alpha-olefins, in particular 1-octene, 1-decene, 1-dodecene, and mixtures thereof.

Silicone oils are also conceivable as base oils a3). Dimethyl silicone oils can be used as base oils a3).

In a further preferred embodiment, the base oil a3) has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 20 mm ² /s to 6000 mm ² /s, more preferably at 40°C of 20 mm ² /s to 1500 mm ² /s, in particular at 40°C of 45 mm ² /s to 700 mm ² /s.

In a further preferred embodiment, the base oil a) has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 20 mm ² /s to 6000 mm ² /s, more preferably at 40°C of 20 mm ² /s to 1500 mm ² /s, in particular at 40°C of 45 mm ² /s to 700 mm ² /s.

In a preferred embodiment, the proportion of additive b) based on the total weight of the lubricant composition is 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%.

The proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%.

A specific embodiment of the invention comprises a lubricant composition containing: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70

Wt.% to 98 wt.%, based on the total weight of the lubricant composition base oil containing a1) 10 wt.% to 90 wt.%, preferably 15 wt.% to 80 wt.%, in particular 15 wt.% to 50 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, in particular 50 wt.% to 85 wt.%, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, of at least one additive, c) optionally 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition, of at least one thickener.

For the specific embodiment of the lubricant composition according to the invention, the preferred embodiments of the lubricant composition according to the invention described above and below apply mutatis mutandis. For example, the combined proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2), based on the total weight of the base oil, is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%.

In a particularly preferred embodiment of the invention, the lubricant composition contains: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%, based on the total weight of the lubricant composition base oil containing a1) 15 wt.% to 50 wt.% or 10 wt.% to 40 wt.%, preferably 10

Wt.% to 30 wt.%, in particular 10 wt.% to 24 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, wherein the ethylene oxide homopolymer a1) is preferably prepared starting from ethylene oxide as monomer and/or ethylene glycol as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, more preferably water and/or C« monoalcohol, in particular water, methanol and mixtures thereof, a2) 50 wt.% to 85 wt.%, preferably 76 wt.% to 85 wt.%, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, wherein the ethylene oxide/propylene oxide copolymer a2) preferably contains at least one structural group of the general formula (II) includes, wherein

R is selected from H and C1-6 alkyl, preferably from H, C« alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary and wherein the structural group of the general formula (II) is connected via the serpentine bond to a terminal group or a bridging group, wherein the proportion of ethylene oxide homopolymer a1) and

Ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, at least 80 wt.%, for example 80

wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), wherein the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is preferably selected from esters, ethers, with the exception of ethylene oxide homopolymers and ethylene oxide/propylene oxide copolymers, and mixtures thereof b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, of at least one additive, preferably selected from corrosion inhibitors, antioxidants, Metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction value modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof, c) optionally 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition, of at least one thickener, preferably selected from metal simple soaps of elements of the first main group, metal simple soaps of elements of the second main group, aluminum simple soaps, metal complex soaps of elements of the first main group, metal complex soaps of elements of the second main group, aluminum complex soaps, urea thickeners, metal sulfonate thickeners, inorganic or organic solid lubricants, preferably wax, in particular native wax, polyethylene wax, polypropylene wax, paraffin wax, montan wax, microcrystalline wax, Polyamide wax, polyester wax, metal phosphates, metal oxides, metal carbonates, boron nitride, carbon black, graphite, metal chalcogenides, fully fluorinated polymeric substances, fluorine-free polymers, silicon-containing oxides and mixtures of two or more of these thickeners.

In a particularly preferred embodiment of the invention, the lubricant composition contains: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70

Wt.% to 98 wt.%, based on the total weight of the lubricant composition, a base oil containing a1) 15 wt.% to 50 wt.%, preferably 10 wt.% to 40 wt.%, more preferably 10 wt.% to 30 wt.%, in particular 10 wt.% to 24 wt.%, based on the total weight of the base oil, at least one ethylene oxide homopolymer, wherein the ethylene oxide homopolymer a1) is preferably prepared starting from ethylene oxide as monomer and/or ethylene glycol as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, more preferably water and/or C« monoalcohol, in particular water, methanol and mixtures thereof, a2) 50 wt.% to 85 wt.%, preferably 76 wt.% to 85 wt.%, based on the total weight of the base oil, at least one Ethylene oxide/propylene oxide copolymer, wherein the ethylene oxide/propylene oxide copolymer a2) preferably contains at least one structural group of the general formula (II) includes, wherein

R is selected from H and C1-6 alkyl, preferably from H, C« alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary and wherein the structural group of the general formula (II) is connected via the serpentine bond to a terminal group or a bridging group, wherein the proportion of ethylene oxide homopolymer a1) and

Ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil is at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%, a3) 0 wt.% to 15 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), wherein the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is preferably selected from esters, ethers, with the exception of ethylene oxide homopolymers and ethylene oxide/propylene oxide copolymers, and mixtures thereof, b) 0 wt.% to 15 wt.%, based on the total weight of the lubricant composition, of at least one additive, preferably selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, Pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof, c) 0 wt.% to 45 wt.%, based on the total weight of the lubricant composition, of at least one thickener, preferably selected from metal simple soaps of elements of the first main group, metal simple soaps of elements of the second main group, aluminum simple soaps, metal complex soaps of elements of the first main group, metal complex soaps of elements of the second main group, aluminum complex soaps, urea thickeners, metal sulfonate thickeners, inorganic or organic solid lubricants, preferably wax, in particular native wax, polyethylene wax, polypropylene wax, paraffin wax, montan wax, microcrystalline wax, polyamide wax, polyester wax, metal phosphates, metal oxides, metal carbonates, boron nitride, carbon black, graphite, metal chalcogenides, fully fluorinated polymeric substances, fluorine-free polymers, silicon-containing oxides and mixtures of two or more this thickener.

In a particularly preferred embodiment of the invention, the lubricant composition contains: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70

Wt.% to 98 wt.%, based on the total weight of the lubricant composition Base oil containing a1) 5 wt.% to 45 wt.%, preferably 8 wt.% to 40 wt.%, more preferably 8 wt.% to 25 wt.%, based on the total weight of the lubricant composition of at least one ethylene oxide homopolymer, wherein the ethylene oxide homopolymer a1) is preferably prepared starting from ethylene oxide as monomer and/or ethylene glycol as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, more preferably water and/or C1-4 monoalcohol, in particular water, methanol and mixtures thereof, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, more preferably 50 wt.% to 85 wt.%, in particular 76 wt.% to 85 wt.%, based on the total weight of the lubricant composition at least one ethylene oxide/propylene oxide copolymer, wherein the ethylene oxide/propylene oxide copolymer a2) preferably contains at least one structural group of the general formula (II) includes, wherein

R is selected from H and C1-6 alkyl, preferably from H, C« alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary and wherein the structural group of the general formula (II) is connected to a terminal group or a bridging group via the serpentine bond, wherein the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%, a3) optionally 1 wt.% to 8 wt.%, preferably 2.5 wt.% to 5 wt.%, based on the total weight of the lubricant composition, based on the total weight of the lubricant composition, of at least one base oil different from a1) and a2), wherein the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is preferably selected from esters, ethers, with the exception of ethylene oxide homopolymers and ethylene oxide/propylene oxide copolymers, and mixtures thereof, b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, at least one additive, preferably selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof, c) optionally 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition, at least one thickener, preferably selected from metal simple soaps of elements of the first main group, metal simple soaps of elements of the second main group, aluminum simple soaps, metal complex soaps of elements of the first main group, metal complex soaps of elements of the second main group, Aluminum complex soaps, urea thickeners, metal sulfonate thickeners, inorganic or organic solid lubricants, preferably wax, in particular native wax, polyethylene wax, polypropylene wax, paraffin wax, montan wax, microcrystalline wax, polyamide wax, polyester wax, metal phosphates, metal oxides, metal carbonates, boron nitride, carbon black, graphite, metal chalcogenides, fully fluorinated polymeric substances, fluorine-free polymers, silicon-containing oxides and mixtures of two or more of these thickeners. In a likewise particularly preferred embodiment of the invention, the lubricant composition contains: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%, based on the total weight of the lubricant composition, of base oil containing a1) 5 wt.% to 45 wt.%, preferably 8 wt.% to 40 wt.%, more preferably 8 wt.% to 25 wt.%, based on the total weight of the lubricant composition, of at least one ethylene oxide homopolymer, wherein the ethylene oxide homopolymer a1) is preferably prepared starting from ethylene oxide as monomer and/or ethylene glycol as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, more preferably water and/or C1-4 monoalcohol, in particular water, methanol and mixtures thereof, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, more preferably 50 wt.% to 85 wt.%, in particular 76 wt.% to 85 wt.%, based on the total weight of the lubricant composition, of at least one ethylene oxide/propylene oxide copolymer, wherein the ethylene oxide/propylene oxide copolymer a2) preferably contains at least one structural group of the general formula (II) includes, wherein

R is selected from H and C1-6 alkyl, preferably from H, C1-4 alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary and wherein the structural group of the general formula (II) is connected via the serpentine bond to a terminal group or a bridging group, wherein the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%, a3) 0 wt.% to 8 wt.%, based on the total weight of the lubricant composition, based on the total weight of the lubricant composition, at least one base oil different from a1) and a2), wherein the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is preferably selected from esters, ethers, with the exception of ethylene oxide homopolymers and ethylene oxide/propylene oxide copolymers, and mixtures of which, b) 0 wt.% to 15 wt.%, based on the total weight of the lubricant composition, of at least one additive, preferably selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof, c) 0 wt.% to 45 wt.%, based on the total weight of the lubricant composition, of at least one thickener, preferably selected from metal simple soaps of elements of the first main group, metal simple soaps of elements of the second main group, aluminum simple soaps, metal complex soaps of elements of the first main group, metal complex soaps of elements of the second main group, aluminum complex soaps, urea thickeners, metal sulfonate thickeners, inorganic or organic solid lubricants, preferably wax, in particular native wax, polyethylene wax, polypropylene wax, Pa raff in wax, montan wax, microcrystalline wax, polyamide wax, polyester wax, metal phosphates, metal oxides, metal carbonates, boron nitride, carbon black, graphite, metal chalcogenides, fully fluorinated polymeric substances, fluorine-free polymers, silicon-containing oxides and mixtures of two or more of these thickeners.

Lubricating oils and greases

The lubricant compositions according to the invention can be designed either as a lubricating oil or as a lubricating grease. Lubricating greases are compositions that contain a liquid phase (at room temperature 20°C and atmospheric pressure of 1013 hPa) and solids. Thus, in contrast to lubricating oils, lubricating greases contain at least one thickener as an additive. Thickeners are solid substances that are almost or completely insoluble in the base oils (insoluble solids) and have a thickening effect. Thickener c) preferably has a solubility in the base oil at 20°C of less than 0.1 wt.%, more preferably less than 0.05 wt.%. No solubility is present if thickener c) does not form a homogeneous phase with the base oil. To determine solubility, the mixture of base oil and thickener c) is preferably heated to 100°C while simultaneously stirring, followed by cooling. The test to determine whether a homogeneous phase is formed is carried out after cooling to 20°C.

In lubricating greases, the proportion of thickener c) is preferably at least 3 wt.%. Thickeners can also influence friction and wear. A special embodiment of such thickeners are inorganic and organic solid lubricants.

Lubricating oils can also be distinguished from lubricating greases phenomenologically by various characteristics. One phenomenological difference is that, at least at low shear rates (especially in the range of 10 s ^-1 to 100 s' ¹ ), lubricating oils exhibit Newtonian flow behavior, whereas lubricating greases exhibit a deviation from Newtonian flow behavior even at low shear rates (especially in the range of 10 s ^-1 to 100 s ^-1 ).

To determine whether Newtonian flow behavior is present, the shear viscosity can be measured at two different shear rates (preferably 10 s ^-1 and 100 s ^-1 ). Shear viscosity can be measured according to DIN 51810 (April 2017, Sheet 1: Shear Viscosity with a Rotational Viscometer and a Cone/Plate Measuring System), with the exception that the shear rate is set to the values under investigation (10 s ^-1 ; 100 s' ¹ ). The temperature during the measurement is 25°C. If the shear viscosity is the same at both different shear rates, the fluid exhibits Newtonian behavior and is a lubricating oil. If the shear viscosity is different at the two different shear rates, the fluid does not exhibit Newtonian flow behavior and is therefore a lubricating grease. If individual lubricants that contain a liquid phase and solids (at room temperature of 20°C and atmospheric pressure of 1013 hPa) exceptionally behave phenomenologically like lubricating oils, they are still considered lubricating greases.

The consistency of lubricating greases can be determined using a standardized measurement method in the form of worked penetration according to DIN ISO 2137, December 2016 edition. The worked penetration is measured after the lubricating grease has been worked in a grease kneader or lubricating grease walker using a penetrometer as the penetration depth of a standard cone under defined conditions. The measured cone penetration is then assigned to a defined NLGI class (NLGI = National Lubricating Grease Institute) according to DIN 51818 DIN 51818-2024-02. When measured according to DIN ISO 2137, December 2016 edition, lubricating greases according to the invention preferably exhibit a worked penetration of 85 to 475, more preferably 220 to 340 cone penetration in 0.1 mm.

The lubricant composition according to the invention is preferably designed as a lubricating oil. The combination of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) is particularly suitable for this purpose, since a1) and a2) exhibit particularly good friction values for transmission applications, where lubricating oils are generally used.

If a component used in the lubricant compositions according to the invention has several effects, e.g. as a thickener and friction coefficient modifier, it is only taken into account once in terms of quantity.

lubricating oil

A preferred embodiment of the invention is a lubricant composition in the form of a lubricating oil, comprising a) a base oil containing a1) at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer, a3) optionally at least one base oil different from a1) and a2), b) optionally at least one additive.

For the lubricant compositions in the form of a lubricating oil, the embodiments of the lubricant composition according to the invention described above and below apply mutatis mutandis.

For example, the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%.

In a further preferred embodiment, the lubricant composition in the form of a lubricating oil contains the base oil in an amount of 80 wt.% to 99 wt.%, preferably 85 wt.% to 98 wt.%, in particular 90 wt.% to 98 wt.%, based on the total weight of the lubricant composition.

In a further preferred embodiment, the additive (b) is selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof.

In a further preferred embodiment of the invention, the lubricant composition according to the invention, in the form of a lubricating oil, has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 20 mm ² /s to 6000 mm ² /s, more preferably at 40°C of 20 mm ² /s to 1500 mm ² /s, in particular at 40°C of 45 mm ² /s to 700 mm ² /s. In a further preferred embodiment of the invention, the lubricant composition according to the invention, in the form of a lubricating oil, has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 20 mm ² /s to 100 mm ² /s, more preferably at 40°C of 20 mm ² /s to 68 mm ² /s, in particular at 40°C of 20 mm ² /s to 46 mm ² /s. These viscosities are particularly suitable for lubricating transmissions in electric vehicles, in particular wet or dry electric axles.

In a further preferred embodiment of the invention, the lubricant composition according to the invention, in the form of a lubricating oil, has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 20 mm ² /s to 25,000 mm ² /s, more preferably at 40°C of 20 mm ² /s to 3,200 ^{mm 2} /s, more preferably at 40°C of 20 mm ² /s to 1,500 mm 2 /s, more preferably at 40°C of 68 mm ² /s to 680 mm ² /s, in particular at 40°C of 100 mm ² /s to 320 mm ² /s. These viscosities are particularly suitable for lubricating gears of equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed, since they have favorable toxicological properties.

A preferred embodiment of the invention is a lubricant composition in the form of a lubricating oil, comprising a) 80 wt.% to 99 wt.%, preferably 85 wt.% to 98 wt.%, in particular 90 wt.% to 98 wt.%, based on the total weight of the lubricant composition, base oil comprising a1) 10 wt.% to 90 wt.%, preferably 15 wt.% to 80 wt.%, in particular

15 wt.% to 50 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) 10 wt.% to 90 wt.%, preferably 20 wt.% to 85 wt.%, in particular

50% to 85% by weight, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition, of at least one additive.

Grease

A further preferred embodiment of the invention is a lubricant composition in the form of a lubricating grease, comprising a) a base oil comprising a1) at least one ethylene oxide homopolymer, preferably with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol, a2) at least one ethylene oxide/propylene oxide copolymer, a3) optionally at least one base oil different from a1) and a2), b1) at least one thickener, b2) optionally at least one further additive.

For lubricant compositions in the form of a lubricating grease, the embodiments of the lubricant composition according to the invention described above and below apply mutatis mutandis.

Thus, the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is preferably at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%. In a further specific embodiment, the lubricant composition in the form of a lubricating grease contains the base oil in an amount of 50 wt.% to 97 wt.%, preferably 60 wt.% to 95 wt.%, more preferably 70 wt.% to 93 wt.%, in particular 80 wt.% to 90 wt.%, based on the total weight of the lubricant composition.

In a further preferred embodiment, the additive (b) is selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers and mixtures thereof.

Thickener c)

The lubricant composition in the form of a lubricating grease contains at least one thickener c). The thickener c) preferably has a solubility in the base oil a) at 20°C of less than 0.1 wt.%, more preferably less than 0.05 wt.%. Solubility is present when the thickener c) forms a homogeneous phase with the base oil a). To determine solubility, the mixture of base oil and thickener c) is preferably heated to 120°C while stirring, followed by cooling. The test for the formation of a homogeneous phase is carried out after cooling to 20°C.

The proportion of the at least one thickener c) is preferably 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition.

Preferably, the thickener c) is selected from metal simple soaps of elements of the first main group, metal simple soaps of elements of the second main group, aluminum simple soaps, metal complex soaps of elements of the first main group, metal complex soaps of elements of the second main group, aluminum complex soaps, urea thickeners, metal sulfonate thickeners, inorganic or organic solid lubricants, preferably wax, in particular native wax, polyethylene wax, polypropylene wax, paraffin wax, montan wax, microcrystalline wax, polyamide wax, polyester wax, metal phosphates, metal oxides, metal carbonates, boron nitride, carbon black, graphite, metal chalcogenides, fully fluorinated polymers substances, fluorine-free polymers, silicon-containing oxides and mixtures of two or more of these thickeners.

Metal monosoaps suitable as thickeners c) are preferably metal monosoaps of the elements of the first and second main groups of the Periodic Table, especially lithium soaps. The metal monosoaps are preferably derived from at least one saturated or unsaturated C5-22 fatty acid, preferably at least one C14-20 fatty acid, or a derivative thereof. This includes, for example, hydrogenated castor oil, i.e., the glyceride of 12-hydroxystearic acid. In a preferred embodiment, thickener c) comprises at least one lithium soap. Particularly preferred lithium soaps are lithium salts of stearic acid.

Metal complex soaps suitable as thickeners c) are preferably metal complex soaps of the elements of the first and second main groups of the periodic table, such as lithium complex soaps, sodium complex soaps, calcium complex soaps, and aluminum complex soaps. Lithium complex soaps are preferred.

Suitable metal complex soaps can be obtained by reacting a metal base (such as a hydroxide, oxide or carbonate) with c1) at least one carboxylic acid component having 10 to 32 carbon atoms, preferably selected from unsaturated or saturated C10-C32 monocarboxylic acids or unsaturated or saturated C10-C32 hydroxy monocarboxylic acids and derivatives of said C10-C32 monocarboxylic acids and C10-C32 hydroxy monocarboxylic acids and c2) at least one complexing agent.

Component c1) is preferably selected from saturated or unsaturated C12-C22 monocarboxylic acids, saturated or unsaturated C12-C22 hydroxymonocarboxylic acids, and their esters and mixtures. In particular, the monocarboxylic acids and hydroxymonocarboxylic acids c1) are selected from lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, myristoleic acid, palmitoleic acid, oleic acid, linoleic acid, arachidonic acid, behenic acid, 12-hydroxystearic acid, 17-hydroxystearic acid, 2-hydroxytetradecanoic acid, 3-hydroxytetradecanoic acid, 2-hydroxyhexadecanoic acid, 3-hydroxyhexadecanoic acid, and mixtures thereof.

The complexing agent c2) is preferably selected from saturated or unsaturated C2-Ci6 dicarboxylic acids, saturated or unsaturated C2-C8 hydroxy Monocarboxylic acids, derivatives, and mixtures thereof. Particularly suitable dicarboxylic acids b2) are adipic acid, sebacic acid, azelaic acid, 3-tert-butyladipic acid, and their esters and mixtures. Hydroxybenzoic acids, e.g., salicylic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2-hydroxy-4-hexylbenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 4-hydroxy-4-methoxybenzoic acid, and mixtures thereof, are also particularly suitable as component b2).

Most preferably, the lithium complex soap comprises lithium salts of 12-hydroxystearic acid combined with azelaic acid or sebacic acid, in particular 12-hydroxystearic acid combined with azelaic acid.

In a preferred embodiment, the thickener c) is a urea thickener, in particular an alkylated and/or arylated (oligo)urea. Preferred urea thickeners are the reaction products of at least one diisocyanate with at least one amine selected from monoamines, polyamines, and mixtures thereof. The diisocyanate is preferably selected from 2,4-diisocyanatotoluene, 2,6-diisocyanatotoluene, 4,4'-diisocyanatodiphenylmethane, 2,4'-diisocyanatophenylmethane, 4,4'-diisocyanatodiphenyl, 4,4'-diisocyanato-3,3'-dimethylphenyl, 4,4'-diisocyanato-3,3'-dimethylphenylmethane, and mixtures thereof.

Preferably, the amine is selected from monoamines of the formula R ^a ₂ NR ^b , diamines of the formula R ^a ₂ NR ^c -NR ^a 2 and mixtures thereof, where

R ^a is independently selected from hydrogen, linear or branched Ci-C ₂₂ alkyl and C ₆ -C 14 aryl,

R ^b is independently selected from linear or branched Ci-C ₂₂ alkyl and C6-C14 aryl radicals,

R ^c is a divalent bridging group preferably selected from Ci-C ₂₂ alkylene and Ce-Ci4 arylene.

Metal sulfonate thickeners suitable as thickeners c) are, in particular, calcium sulfonate thickeners. Calcium sulfonate thickeners specifically contain crystalline calcium carbonate in the form of calcite and calcium salts of acids, especially aromatic sulfonic acids, most preferably alkylbenzenesulfonic acids, carboxylic acids, especially stearic acid, 12-hydroxystearic acid, acetic acid, boric acid, and mixtures thereof. Waxes suitable as thickeners c) include, in particular, polyethylene (PE), polypropylene (PP), and polyamide (PA) wax. The wax preferably has a melting or decomposition point, measured according to DIN EN ISO 11357-1, edition 2008.04, of greater than 100°C.

Metal chalcogenides suitable as thickeners c) are in particular molybdenum disulfide, tungsten disulfide and metal selenides.

Highly fluorinated polymeric substances suitable as thickeners c) are, in particular, PTFE. However, this is not a preferred embodiment of the invention.

Also suitable as thickeners c) are fluorine-free components that differ from the previously mentioned thickeners b1). The fluorine-free components preferably have an average particle size (D50) of less than 80 pm, for example 1 pm to 80 pm, more preferably from 1 pm to 50 pm, even more preferably from 1 pm to 20 pm, in particular from 1 pm to 15 pm, in each case measured according to ISO 13320-1, edition 2020-01. Preferred further fluorine-free components are boron nitride, carbon black, graphite, graphene, tin(IV) sulfide, zinc(II) sulfide, tungsten sulfide. Preferred further fluorine-free components are talc, bentonite, mica, and pyrogenic silicon dioxide, which may be functionalized with organic groups. A special type of bentonite is montmorillonite, whose sodium ions may be partially or completely exchanged for ammonium ions. Other suitable fluorine-free thickeners b1) include aluminosilicates, aluminum oxide, and silica (e.g., Aerosil). Other suitable fluorine-free thickeners c) include nanoparticulate silicon dioxide functionalized with organic groups, zinc pyrophosphate, calcium (pyro)phosphate, and zirconium hydrogen phosphate. Other suitable fluorine-free thickeners c) include melamine derivatives selected from melamine cyanurate, melamine phosphate, and 1,3,5-triazine-2,4,6 (1H,3H,5H)-trithione.

In a further preferred embodiment, the thickener c) is a combination of two or more of the aforementioned further thickeners.

In a further preferred embodiment, the lubricant composition has a viscosity index of over 150.

Additives b: The lubricant composition according to the invention may comprise at least one additive b). The at least one additive b) is preferably selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, free radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving high-pressure properties, adhesion improvers, defoamers, and mixtures thereof.

If present, the lubricant composition contains the at least one additive b) preferably in an amount of 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition.

Corrosion inhibitors

The lubricant composition according to the invention may contain at least one corrosion inhibitor as additive b).

Corrosion inhibitors neutralize acidic reaction products, e.g., from the oxidation of the base oil or additive degradation. This reduces or prevents corrosive attack. Suitable corrosion inhibitors are the salts of various acids, such as sulfonates, naphthenates, carboxylates, amine phosphates, succinic acid monoesters, or partial polyol esters. The corrosion inhibitor is preferably selected from calcium sulfonates, preferably overbased calcium sulfonates with a base number (TBN) of 100 to 500 mg KOH/g, amine-neutralized phosphates, alkylated calcium naphthalenesulfonates, oxazoline derivatives, imidazole derivatives, succinic acid monoesters, benzotriazole, N-alkylated benzotriazoles, and mixtures thereof.

The lubricant composition according to the invention preferably contains at least one corrosion inhibitor in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Antioxidants

The lubricant composition according to the invention may contain at least one antioxidant as an additive. Antioxidants increase resistance to aging caused by oxidative and/or thermal stress at the lubrication point. Oxidation can produce acids and oil-insoluble components, which form contaminants that can settle on the lubrication point.

Suitable antioxidants are aromatic amine antioxidants such as alkylated phenyl-alpha-naphthylamine, dialkyldiphenylamine, aralkylated diphenylamine, sterically hindered phenols such as butylhydroxytoluene (BHT), bis-2,6-di-t-butylphenol derivatives, sulfur-containing hindered phenols, sulfur-containing hindered bisphenol, and mixtures thereof.

The lubricant composition according to the invention preferably contains at least one antioxidant in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Metal deactivators

The lubricant composition according to the invention may contain at least one metal deactivator (additive for protection against metal influences) as an additive.

Various metals, such as copper and its compounds, are catalysts for the formation of peroxides and thus contribute to oxidation. Suitable metal deactivators are chelating agents that passivate the metal surface. Non-limiting examples of metal deactivators are triazoles or thiadiazoles, especially aryltriazoles such as benzotriazole and tolyltriazole, alkyl derivatives of such triazoles, and benzothiadiazoles such as R(CeH3)N2S, where R is H or C1- to C8-alkyl.

The lubricant composition according to the invention preferably contains at least one metal deactivator in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Wear protection agents The lubricant composition according to the invention may contain at least one wear protection agent as an additive.

Wear protection agents are used to prevent wear caused by tribological processes, such as fluid and mixed friction

The antiwear agent is preferably selected from amine-neutralized phosphates, alkylated and non-alkylated triaryl phosphates, alkylated and non-alkylated triaryl thiophosphates, Zn, Mo or W dialkyl dithiophosphates, Zn, Mo or W diaryl dithiophosphates, carbamates, thiocarbamates, Zn, Mo or W dithiocarbamates, dimercaptothiadiazoles, organoborates, organophosphites and mixtures thereof.

The lubricant composition according to the invention preferably contains at least one wear protection agent in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Viscosity index improver

The lubricant composition according to the invention may contain at least one viscosity index improver (VI improver) as an additive.

Examples of VI improvers are olefin copolymers, polyalkyl methacrylates and dispersing olefin copolymers.

The lubricant composition according to the invention preferably contains at least one VI improver in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Extreme pressure additives The lubricant composition according to the invention may contain at least one extreme pressure additive as an additive.

High-pressure additives act as topcoating agents and/or surface-active substances.

Preferred extreme pressure additives are selected from thiophosphates such as zinc dithiophosphate, molybdenum oxide sulfide dithiophosphate, molybdenum amine compounds, sulfur compounds such as sulfurized oils and fats, sulfurized fatty acids, sulfurized fatty acid esters, alkylated polysulfides and mixtures thereof.

The lubricant composition according to the invention preferably contains at least one high-pressure additive in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Pour point improvers

The lubricant composition according to the invention may contain at least one pour point improver as an additive.

Preferred pour point improvers are selected from linear or branched, alkylated, acrylated, and/or aliphatic polymers and copolymers, which can be used individually or in combination. A specific example of a pour point depressant is polyalkyl methacrylate.

The lubricant composition according to the invention preferably contains at least one pour point improver in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Adhesion improver

The lubricant composition according to the invention may contain at least one adhesion improver as an additive. Preferred additives to improve adhesion are selected from long-chain polar polymers that give the oil or grease increased adhesion to the surface to be lubricated.

The lubricant composition according to the invention preferably contains at least one adhesion improver in an amount of at least 0.1 wt.%, preferably from 0.1 wt.% to 5 wt.%, particularly preferably at least 0.5 wt.%, preferably from 0.5 wt.% to 5 wt.%, in particular at least 1.0 wt.%, preferably from 1 wt.% to 5 wt.%, based on the total weight of the lubricant composition.

Defoamers

The lubricant composition according to the invention preferably contains at least one defoamer in an amount of at least 0.01 wt.%, preferably from 0.01 wt.% to 0.1 wt.%, particularly preferably from 0.01 wt.% to 0.05 wt.%, based on the total weight of the lubricant composition.

Preferred defoamers are selected from silicon dioxide, silicone oils, (poly)acrylates, and mixtures thereof.

Uses

The invention further relates to the use of at least one ethylene oxide homopolymer a1) in combination with at least one ethylene oxide/propylene oxide copolymer a2), where a1) and a2) are as defined above and below, optionally in combination with at least one base oil a3) different from a1) and a2), as base oil of a lubricant composition for lubricating tribological systems, preferably selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or gears of work equipment for processing foodstuffs, luxury goods, cosmetics, pharmaceuticals and/or animal feed and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools and/or bearings of work equipment for processing foodstuffs, luxury goods, cosmetics, pharmaceuticals and/or animal feed. Power tools are tools powered by electricity, batteries, or compressed air, unlike manual tools, which require physical effort to operate. Preferred power tools include drills, saws, grinders, nail pliers, and impact wrenches. They are commonly used in construction, woodworking, metalworking, and other industries, as well as for home improvement projects.

A further subject matter of the invention is the use of a lubricant composition according to one or more of the embodiments described above and below for lubricating tribological systems, preferably selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or gears of work equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools and/or bearings of work equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed.

In a preferred embodiment, the use comprises the lubrication of tribological systems selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools.

A further subject matter of the invention is the use of a lubricant composition according to one or more of the embodiments described above and below, designed as a lubricating oil, which contains at least one ethylene oxide homopolymer a1) in combination with at least one ethylene oxide/propylene oxide copolymer a2), where a1) and a2) are as defined above and below, optionally in combination with at least one base oil a3) different from a1) and a2) as base oil, for lubricating tribological systems, preferably selected from gears, in particular industrial gears, gears in electric vehicles, gears which are components of power tools and/or gears of work equipment for processing foodstuffs, luxury goods, cosmetics, pharmaceuticals and/or animal feed and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, Storage of components of power tools and/or storage of work equipment for the processing of food, luxury goods, cosmetics, pharmaceuticals and/or animal feed.

In a preferred embodiment, the use of the lubricant composition formed as a lubricating oil comprises the lubrication of tribological systems selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools.

Preferred uses include gears that are components of power tools and/or industrial gears. Particularly preferred is the lubrication of equipment used in the processing of food, luxury goods, cosmetics, pharmaceuticals, and/or animal feed.

Open and closed gears can be lubricated. In a preferred embodiment, closed gears are lubricated, as the system's properties can be maintained particularly well.

A further subject matter of the invention is a tribological system, preferably selected from gears and/or bearings, which contain a lubricant composition according to one or more of the embodiments described above and below.

Preferably, the tribological system is selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or gears of work equipment for the processing of food, luxury goods, cosmetics, pharmaceuticals and/or animal feed and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools and/or bearings of work equipment for the processing of food, luxury goods, cosmetics, pharmaceuticals and/or animal feed.

In a preferred embodiment, the tribological system is selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or selected from bearings, in particular Bearings in industrial plants, bearings in vehicles such as automobiles, bearings that are components of power tools.

Preferred tribological systems are gears that are components of power tools and/or gears in electric vehicles, particularly wet or dry electric axles. Particularly preferred tribological systems are tools for processing food, luxury goods, cosmetics, pharmaceuticals, and/or animal feed. Particularly preferred gears are enclosed gears.

Character description

Figure 1: Stribeck curves at 25°C of compositions according to the invention and a comparison composition with viscosity at 40°C around 20 mm ² /s

Figure 2: Stribeck curves at 40°C of compositions according to the invention and a comparison composition with viscosity at 40°C around 20 mm ² /s

Figure 3: Traction curves at 60°C, 2.5 m/s for the inventive

Compositions and a comparison composition with viscosity at 40°C around 20 mm ² /s

Figure 4: Stribeck curves at 40°C of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s

Figure 5: Stribeck curves at 25°C of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s

Figure 6: Stribeck curves at 60°C of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s

Figure 7: Traction curves at 25°C, 2.5 m/s, 50 N of the inventive

Composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s

Figure 8: Traction curves at 40°C, 2.5 m/s of the composition according to the invention

7 and the comparison composition 2 with viscosity at 40°C around 100 mm ² /s Figure 9: Traction curves at 60°C, 2.5 m/s of the composition according to the invention

7 and the comparison composition 2 with viscosity at 40°C around 100 mm ² /s

Figure 10: Stribeck curves at 25°C of the inventive example 12 and the comparative example 3 with viscosity at 40°C around 320 mm ² /s

Figure 11 : Stribeck curves at 40°C of the inventive example 12 and the comparative example 3 with viscosity at 40°C around 320 mm ² /s

Figure 12: Stribeck curves at 60°C of the inventive example 12 and the comparative example 3 with viscosity at 40°C around 320 mm ² /s

Figure 13: Traction curves at 25°C, 2.5 m/s 50 N of the inventive example 12 and the comparative composition 3 with viscosity at 40°C around 320 mm ² /s

Figure 14: Traction curves at 40°C, 2.5 m/s of the inventive example 12 and the comparative composition 3 with viscosity at 40°C around 320 mm ² /s

Figure 15: Traction curves at 60°C, 2.5 m/s of the inventive example 12 and the comparative composition 3 with viscosity at 40°C around 320 mm ² /s

Figure 16: Stribeck curves at 25°C of the inventive composition 7 and the comparative compositions 2 and 5 with viscosity at 40°C around 100 mm ² /s

Figure 17: Stribeck curves at 40°C of the inventive composition 7 and the comparative compositions 2 and 5 with viscosity at 40°C around 100 mm ² /s

Figure 18: Traction curves at 60°C, 2.5 m/s of the inventive example 7 and the comparative compositions 2 and 5 with viscosity at 40°C around 100 mm ² /s

Figure 19: Change in the masses of different samples during open storage Figure 20: Comparison of the friction of the inventive composition 20 and the comparative example 26

Figure 21 : Traction curves of composition 20 and comparative example 26 at 40°C, 2.5 m/s

Figure 22: Stribeck curves at 40°C of the compositions 7 according to the invention,

49, 50 and the comparative compositions 2 with viscosity at 40°C around 100 mm ² /s

Figure 23: Traction curves at 40°C, 2.5 m/s of the inventive

Compositions 7, 49, 50 and comparative composition 2 with viscosity at 40°C around 100 mm ² /s

Figure 24: Stribeck curve of the formulations 38, 44 and 51 according to the invention at

60°C

Figure 25: Traction curve of the inventive formulations 38, 44 and 51 at

60°C, 2.5 m/s

Figure 26: Stribeck curve at 40°C of the composition 67 according to the invention and

68 and the comparison composition 27, with viscosity of 220 mm ² /s at 40°C

Figure 27: Traction curve at 40°C, 2.5 m/s, 50 N of the inventive

Composition 67 and 68 and the comparative composition 27, with viscosity of 220 mm ² /s at 40°C

The following examples serve to illustrate the invention without limiting it in any way.

EXAMPLES

I. Application examples In the following application examples, all kinematic viscosities are given in ^mm² /s, all densities in g/ml, and the specific resistance in ohms*cm. All tests were conducted with one batch per material. The EO/PO copolymers used are random copolymers, not block copolymers. The EO/PO copolymers are OH-terminated.

The following polymers are used:

EO homopolymer 1: Hydrogen-terminated (H ₂ O initiated), molecular weight 200 g/mol, viscosity at 40°C approximately 22 mm ² /s, melting point -45 °C. EO homopolymer 1 is supplied as Carbowax™ Polyethylene Glycol (PEG) 200 (Dow).

EO/PO copolymer 1:1, 2-propanediol initiated, molecular weight 3500 g/mol, mass ratio EO to PO approximately 60 to 40, viscosity at 40°C approximately 450 ^mm² /s. The EO/PO copolymer 1 is supplied as Synalox 40 D 300™ (Dow).

EO/PO copolymer 2, butanol-initiated, molecular weight 1600 g/mol, EO to PO mass ratio approximately 45 to 55, viscosity at 40°C approximately 100 ^mm² /s. The EO/PO copolymer 2 is sold as Synalox 55-70 B™ (Dow).

EO/PO copolymer 3, butanol-initiated, molecular weight 570 g/mol, EO to PO mass ratio approximately 47 to 52, viscosity at 40°C approximately 20 ^mm² /s. The EO/PO copolymer 3 is supplied as Breox™ 50 A 20 (BASF).

EO Homopolymer 2: Hydrogen-terminated (H ₂ O initiated), molecular weight 400 g/mol. Viscosity at 40°C approximately 40 mm ² /s. Melting point approximately 6°C. EO Homopolymer 2 is available as Carbowax™ Polyethylene Glycol (PEG) 400 (Dow).

EO/PO Copolymer 4: Blend of two structurally identical EO/PO copolymers with propane-1,2-diol initiator and a mass ratio of ethylene oxide to propylene oxide of 60 to 40. The copolymers exhibit different viscosities. The viscosities at 40°C of the two structurally identical EO/PO copolymers used for blending are approximately 70 ^mm² /s and 150 mm²/ ^s , respectively. The two blending components are sold as Synalox™ 40-D50 and Synalox™ 40-D100 (DOW).

EO Homopolymer 3: Monomethylated, meaning one terminal group is methyl, the other terminal group is an OH group. Kinematic viscosity at 40°C is approximately 14.5 ^mm² /s. Molar mass 350 g/mol. Solidification point approximately -5°C. The EO homopolymer 3 is available from Thermo Fischer Scientific as poly(ethylene glycol methyl ether), average MW 350. Melting point -3°C.

EO Homopolymer 4: Dimethylated, meaning both terminal groups are methyl. Kinematic viscosity at 40°C approximately 3.4 ^mm² /s. Molar mass 250 g/mol. Melting point -23°C. EO Homopolymer 4 is available as polyethylene glycol dimethyl ether 250 from Sigma-Aldrich; melting point approximately -23°C.

EO Homopolymer 5: Polyethylene glycol monomethyl ether, molecular weight 500 g/mol, kinematic viscosity at 40°C approximately 28 ^mm² /s. Melting point approximately 12°C. Homopolymer 5 is available from ThermoFisher Scientific as poly(ethylene glycol methyl ether), molecular weight 500 g/mol. Melting point 12°C.

EO Homopolymer 6: Dimethylated, meaning both terminal groups are methyl. Kinematic viscosity at 40°C approximately 14.6 ^mm² /s, molecular weight 500 g/mol. Melting point 13°C. EO Homopolymer 6 is supplied by Sigma Aldrich as polyethylene glycol dimethyl ether 500.

EO Homopolymer 7: Hydrogen-terminated (H2O-initiated), molecular weight 300 g/mol. Viscosity at 40°C approximately 31.4 ^mm2 /s. Melting point approximately -12°C. Molar mass of 300 g/mol. EO Homopolymer 7 is supplied as polyethylene glycol 300 from Avantor.

BuO/PO copolymer 1: butylene oxide/propylene oxide ratio approx. 1:1, dodecanol-initiated, base oil viscosity approx. 32 mm ² /s. (Ucon OSP 32).

PO homopolymer 1: Butanol-initiated, base oil viscosity approximately 30 ^mm² /s at 40°C. Molar mass approximately 950 g/mol. PO homopolymer 1 is supplied as Synalox™ 100-20 B (Dow).

Ester 1: Trimethylolpropane ester, trimethylolpropane, esterified with C8/C10 fatty acids. Kinematic viscosity at 40°C approx. 20 ^mm² /s. Ester 1 is sold as Priolube™ 3970 (Croda).

EO/PO Copolymer 5: Starter propane-1,2-diol, ethylene oxide to propylene oxide content (mass) of 60 to 40, viscosity at 40°C is 70 mm ² /s. The EO/PO Copolymer 5 is sold as Synalox™ 40-D50 (DOW). EO/PO Copolymer 6, ethylene oxide to propylene oxide content (mass) 75 to 25, both chain ends OH-functionalized, viscosity at 40°C is 17,000 mm ² /s. Molar mass approximately 12,000 g/mol. The EO/PO Copolymer 6 is available as UCON(TM) LUBRICANT 75-H-90,000.

To prepare the mixtures, the respective components are weighed into a beaker and stirred at a maximum of 100°C for up to 1 hour until a clear, homogeneous mixture is obtained. The mixture is then cooled to room temperature and visually inspected after a standing time of approximately 1 hour.

Example A:

Mixtures with base oil viscosity of 20 mm ² /s at 40°C

Various mixtures with base oil viscosity of 20 mm ² /s at 40 are produced. Table 1: Physical characteristics of the compositions according to the invention and the comparative composition with viscosity at 40°C around 20 mm ² /s.

Figure 1 shows the Stribeck curves at 25°C of the compositions according to the invention and the comparison composition with viscosity at 40°C around 20 mm ² /s.

Figure 2 shows the Stribeck curves at 40°C of the compositions according to the invention and the comparison composition with viscosity at 40°C around 20 mm ² /s.

Figure 3 shows the traction curves at 60°C, 2.5 m/s for the compositions according to the invention and the comparison composition with viscosity at 40°C around 20 mm ² /s.

The Stribeck curves at 25°C and 40°C show that the addition of the EO homopolymer significantly reduces the friction coefficients, with higher levels leading to a greater reduction in friction. This is unexpected, as the kinematic viscosities are within a comparable range. The traction curve at 60°C shows that the inventive compositions have advantages over the comparison composition across all slide-roll ratios.

The specific electrical resistance also decreases with increasing proportion of EO homopolymers.

Example B:

Mixtures with base oil viscosity of 100 mm ² /s at 40°C

The following experiments are intended to demonstrate whether the effects described in Example A can also be observed at higher viscosities. In the first step, mixtures of EO/PO copolymer 1 (439.3 mm ² /s at 40°C) with EO homopolymer 1 are prepared to find a mixture whose dynamic viscosity at 60°C is as close as possible to that of pure EO/PO copolymer 2.

Table 2, Mixtures 100 mm ² /s

Inventive Example 7 has very similar viscosity properties to Comparative Example 2, an evaluation of the inventive effect based on the composition can be made well.

Figure 4 shows Stribeck curves at 40°C of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s.

Figure 5 shows Stribeck curves at 25°C of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s. Figure 6 shows Stribeck curves at 60°C of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s.

At 25°C and 40°C, Example 7 according to the invention is advantageous over all speeds, and at 60°C in the EHD range.

Figure 7 shows traction curves at 25°C, 2.5 m/s, 50 N of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s.

Figure 8 shows traction curves at 40°C, 2.5 m/s of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s.

Figure 9 shows traction curves at 60°C, 2.5 m/s of the inventive composition 7 and the comparative composition 2 with viscosity at 40°C around 100 mm ² /s.

In the traction curves, Example 7 according to the invention shows lower friction than Comparative Example 2 across all measured temperatures and all SRRs.

Example C

Mixtures with base oil viscosity of 320 mm ² /s at 40°C

The tests were intended to show whether the effects are also transferable to mixtures with a viscosity of 320 mm ² /s at 40°C.

Table 3: Mixtures 320 mm ² /s

Comparative Example 3 and Inventive Example 12 can be easily compared with each other in terms of their viscosity data.

Figure 10 shows Stribeck curves at 25°C of inventive example 12 and comparative example 3 with viscosity at 40°C around 320 mm ² /s .

Figure 11 shows Stribeck curves at 40°C of inventive example 12 and comparative example 3 with viscosity at 40°C around 320 mm ² /s .

Figure 12 shows Stribeck curves at 60°C of inventive example 12 and comparative example 3 with viscosity at 40°C around 320 mm ² /s.

At all temperatures considered, the friction over the considered speed range is lower in Example 12 according to the invention than in Comparative Example 3. Figure 13 shows traction curves at 25°C and 2.5 m/s for inventive examples 12 and comparative composition 3 with a viscosity at 40°C of around 320 ^mm² /s. Traction curves at 2.5 m/s and 50 N.

Figure 14 shows traction curves at 40°C, 2.5 m/s of the inventive example 12 and the comparative composition 3 with viscosity at 40°C around 320 mm ² /s .

Figure 15 shows traction curves at 60°C, 2.5 m/s of inventive example 12 and comparative composition 3 with viscosity at 40°C around 320 mm ² /s.

For all three temperatures and across all SRR ratios, inventive Example 12 shows lower friction than Comparative Example 3.

Example D) Comparison of a mixture according to the invention with a non-inventive mixture consisting of two EO/PO copolymers (viscosity at 100 mm ² /s at 40°C)

The following example demonstrates the advantage of combining EO homopolymers with EO/PO copolymers compared to the combination of two EO/PO copolymers. Starting from inventive example 7, EO homopolymer 1 is replaced by EO/PO copolymer 3, which has a similar viscosity at 40°C. The ratio of the two base oils in comparative example 5 was slightly adjusted to adjust the mixed viscosities.

Table 4: Mixtures 100 mm ² /s at 40°C; comparison with a non-inventive mixture containing two EO/PO copolymers

Figure 16 shows Stribeck curves at 25°C of the inventive composition 7 and the comparative compositions 2 and 5 with viscosity at 40°C around 100 mm ² /s.

Figure 17 shows Stribeck curves at 40°C of the inventive composition 7 and the comparative compositions 2 and 5 with viscosity at 40°C around 100 mm ² /s.

Figure 18 shows traction curves at 60°C, 2.5 m/s of the inventive example 7 and the comparative compositions 2 and 5 with viscosity at 40°C around 100 mm ² /s.

The results show that Example 7 according to the invention causes significantly lower friction than Comparative Example 5. This shows the advantage of the combination of the EO homopolymer with the EO/PO copolymer, compared to the combination of two EO/PO copolymers.

Example D) Comparison of the miscibility of EO homopolymers with EO/PO copolymers with different initiator compounds and ethylene oxide content

Blends of EO homopolymer 1 with EO/PO copolymer 2 are prepared in different ratios. For comparison, an EO/PO copolymer 4 is used to replace EO/PO copolymer 2. EO/PO copolymer 4 is a blend of two structurally identical EO/PO copolymers with propane-1,2-diol as the initiator compound and a mass ratio of ethylene oxide to propylene oxide of 60 to 40. The copolymers have different viscosities. The viscosities at 40°C of the two structurally identical EO/PO copolymers used for blending are are approximately 70 mm ² /s and 150 mm/ ² . The mixing ratios are selected so that the resulting EO/PO copolymer 4 has the same viscosity as EO/PO copolymer 2. This ensures comparability with regard to viscosities.

Table 6: Mixture of EO homopolymer 1 with EO/PO copolymer 4

Example E) Miscibility of higher molecular weight (600 g/mol and higher) EO homopolymers with EO/PO copolymers with different initiator compounds and different ethylene oxide contents

With EO homopolymers with a molecular weight of 600 and higher, miscibility only occurs above the melting point of the ethylene oxide homopolymer.

Example F) Compositions according to the invention with an EO homopolymer with molecular weight 400g/mol (EO homopolymer 2) with two EO/PO copolymers with different viscosity

Table 8: Compositions according to the invention with EO homopolymer 2 and EO/PO copolymer 2

Table 9: Compositions according to the invention with EO homopolymer 2 and EO/PO copolymer 3

Tables 8 and 9 show that the EO homopolymer 2 is completely miscible with the two EO/PO copolymers investigated.

Example G) Compositions according to the invention with a monomethylated EO homopolymer

Table 10: Compositions according to the invention with EO homopolymer 3 and EO/PO copolymer 3

Table 10 shows that the monomethylated EO homopolymer 3 is completely miscible with the EO/PO copolymer 3.

Example H) Compositions according to the invention with a dimethylated EO homopolymer

Table 11: Compositions according to the invention with EO homopolymer 4 and EO/PO copolymer 3

Table 11 shows that the dimethylated EO homopolymer 4 is completely miscible with the EO/PO copolymer 3.

Example I: Investigations into polyglycols with a structurally different structure as additional base oil components

BuO/PO Copolymer 1 was added in varying amounts to inventive examples 2 and 5, containing EO/PO Copolymer 3 and EO Homopolymer 1. In addition, another inventive composition (Inventive Example 43) containing equal amounts of EO/PO Copolymer 3 and EO Homopolymer 1 was prepared and also mixed with varying amounts of BuO/PO Copolymer 1. Table 12: Mixture tests with the BuO/PO copolymer 1 as additional oil component

Table 12 shows that particularly good and long-term miscibility exists when the concentrations of the components in the ternary mixture do not exceed the ratio [(100*3*proportion of EO homopolymer)/(3*proportion of EO/PO copolymer + 0.33*proportion of other oil component)] a value of 30.

Table 13: Physical data of the mixtures from Table 13, supplemented by another composition according to the invention 43 (only EO/PO copolymer 3 and EO homopolymer 1 in a ratio of 50:50)

Propylene oxide homopolymer 1 (PO homopolymer 1) is added in varying amounts to Inventive Examples 2 and 5, containing EO/PO copolymer 3 and EO homopolymer 1. Additionally, another inventive composition (Inventive Example 43) containing equal amounts of EO/PO copolymer 3 and EO homopolymer 1 is prepared, and this composition is also mixed with varying amounts of propylene homopolymer 1.

Oil component

Table 14 shows that particularly good and lasting miscibility exists when the concentrations of the components in the ternary mixture do not exceed the ratio [(100*3*proportion of EO homopolymer)/(3*proportion of EO/PO copolymer + 0.33*proportion of other oil component)] a value of 30.

Table 15: Physical data of the mixtures from Table 14

Example J: Investigations into esters as additional base oil components

Ester 1 is added to the inventive example 2 containing EO/PO copolymer 3 and EO homopolymer 1 in different amounts.

The table shows that with a ratio of the components according to [(100*3*proportion of EO homopolymer)/(3*proportion of EO/PO copolymer + 0.33*ester proportion of further oil component)] of 23 - 30, there is particularly good and lasting miscibility.

Example K: Water absorption

50.0 g each of EO homopolymer 1, EO/PO copolymers 1 and 3, a mixture of two EO/PO copolymers, and a mixture of EO homopolymer 1 with EO/PO copolymer 3 (Inventive Example 5) are stored openly in 100 ml glass vials. The diameter of the opening is 3.8 cm. During storage, temperatures fluctuate between 21°C and 25°C. The air humidity fluctuates between 35 and 37%. The storage period is carried out for a total of 110 days, and the change in the mass of the sample vial with the sample is measured.

Figure 19 shows the change in the masses of different samples during open storage

In all samples, the mass increases due to the absorption of atmospheric moisture. Samples containing EO homopolymer 1 stabilize at a mass increase of approximately 5%. The EO/PO copolymers are lower at approximately 1%.

The tests show that the mass increase and thus water absorption in the samples with EO homopolymer remains limited. The water content of the samples is also confirmed by measurements according to DIN 51777:2016-08, using the Karl Fischer coulometric method.

L) Proof of friction reduction when using EO homopolymer 2

Comparative Example 26 was compared with Inventive Example 20 with regard to the effect on friction.

Table 18: Physical data of Inventive Example 20 and Comparative Example 26

The table shows that the viscosity data are well comparable, especially at 40°C. Figure 20 shows that the inventive composition 20 exhibits lower friction than Comparative Example 26 when a Stribeck curve is recorded at 40°C. Figure 21 shows the traction curves of the two compositions at 40°C and 2.5 m/s. Again, the inventive composition 20 results in lower friction values.

M) Demonstration of friction reduction when using the monomethylated and dimethylated EO homopolymers 3 and 4. Blends of the two EO homopolymers with the EO/PO copolymer 1 are prepared, which have a kinematic viscosity of approximately 100 mm ² /s at 40°C and thus compare well with the inventive example 7 and the comparative example 2.

Table 19: Comparison of the physical properties of blends with V 40 of approximately 100 mm ² /s prepared with EO homopolymers with different terminal groups

The VI of the EO/PO copolymer 1 is 254. Surprisingly, the addition of the EO homopolymer 4, which itself only has a VI of approximately 140, leads to an increase in the VI. This is surprising, since the blends under H) show no such effect.

Figure 22 shows the Stribeck curves at 40°C of the inventive compositions 7, 49, 50 and Comparative Composition 2 with viscosity at 40°C of around 100 mm ² /s. Figure 23 shows the traction curves at 40°C, 2.5 m/s of the inventive compositions 7, 49, 50 and Comparative Composition 2 with viscosity at 40°C of around 100 mm ² /s. All compositions according to the invention show very similar behavior, the friction values are significantly lower than those of the comparison composition.

N) Measurement results with samples according to the invention containing a third base oil

Two inventive samples with 10 wt.% of additional base oil (PO homopolymer 1 and BuO/PO copolymer 1) are selected from the tests under I). In addition, another sample, inventive sample 51, is prepared starting from the identical inventive mixture 2 by adding 10 wt.% of ester 1.

Table 20: Comparison of the physical properties of blends containing another base oil

The inventive formulations 38, 44 and 51 contain, in addition to the EO homopolymer 1 and an EO/PO copolymer, another base oil (no EO/PO copolymer) and show lower friction than Comparative Example 1 in both the Stribeck curve (Figure 24) and the traction curve at 60°C, 2.5 m/s (Figure 25).

The effect can also be observed at 25°C and 40°C. The effect according to the invention is also maintained in the presence of additional base oils a3).

O) Compositions according to the invention with a dimethylated EO homopolymer with a molecular weight of 500 g/mol, EO homopolymer 6

Table 21: Compositions according to the invention with EO homopolymer 6 and EO/PO copolymer 3

Table 21 shows that the dimethylated EO homopolymer 6 is completely miscible with the EO/PO copolymer 3. The lower molecular weight EO homopolymer 4 shows good miscibility and also very good low-temperature properties.

P) Compositions according to the invention with a monomethylated EO homopolymer with a molecular weight of 500 g/mol, EO homopolymer 5

Table 22: Compositions according to the invention with EO homopolymer 5 and EO/PO copolymer 3

Table 22 shows that the monomethylated EO homopolymer 5 is initially miscible with the EO/PO copolymer 3, but after prolonged standing time, it forms emulsions and is no longer clearly dissolved. In contrast, the lower molecular weight EO homopolymer 3 is significantly more miscible than the EO homopolymer 5. Q) Compositions according to the invention with an EO homopolymer with a molecular weight of 300 g/mol, EO homopolymer 7

EO homopolymer 7, kinematic viscosity at 40°C 31.4 ^mm2 /s, molecular weight 300 g/mol, melting point approx. -13°C.

Table 23: Compositions according to the invention with EO homopolymer 7 and EO/PO copolymer 1.

Table 23 shows that the EO homopolymer 7 is well miscible with the EO/PO copolymer 1. These compositions are particularly suitable for use in

Suitable for food processing machines and transport systems in the food industry because EO/PO Copolymer 1 has a sufficiently high molecular weight. R) Formation of the lubricating film thickness in two compositions according to the invention

Table 24: Two compositions according to the invention with V40 of approximately 220 mm ² /s, lubricating film thickness

Although Samples 67 and 68 have comparable viscosities, Sample 67, with its lower EO homopolymer content, exhibits a lubricating film thickness almost twice as high. This is preferred because it significantly reduces the risk of wear.

Figures 26 and 27 show that inventive examples 67 and 68 exhibit advantageous friction properties compared to Comparative Example 27, particularly at higher speeds. Figure 26 shows that the friction of inventive mixture 67 is significantly lower at low speeds than for inventive mixture 68, consistent with the results of the layer thickness measurement.

Measurement methods

Melting point / glass transition point

Melting points / glass transition points are measured according to DIN EN ISO 11357-3:2018 with a heating rate of 10°K/min. The determination of the melting point according to DIN EN ISO 11357-3:2018 can be used to determine whether a substance exhibits a melting point or glass transition point below 20°C.

Molecular weight Mn,

It is measured according to DIN 55672-1:2016-03, for all PG.

Percentage of water

The water content can be measured using the Karl Fischer method according to DIN 51777:2016-08.

Viscosity index

The viscosity index (VI) can be calculated from the kinematic viscosity, as specified in DIN ISO 2909:2004-08.

Density

The determination of the densities at 20°C (p20), 40°C (p40), 100°C (p100) is carried out according to DIN 51757:2011-01 using a Stabinger rheometer.

Pour point

The pour point is determined according to DIN ISO 3016-2017-11.

Solubility

The solubility of a substance in the base oil is determined when the substance under investigation forms a homogeneous phase with the base oil. To determine solubility, the mixture of base oil and substance is preferably first heated to 100°C while stirring, followed by cooling. The test for the formation of a homogeneous phase is performed after cooling to 20°C.

Stribeck curves and traction curves

Stribeck curves and traction curves were created using the MTM device from PCS-Instruments. Surface roughness Ra = 10 nm

Lubricating film thickness measurements at 40°C and 60°C

The lubricant film thicknesses were determined using the EHD2 tribometer from PCS-Instruments.

Claims

Patent claims 1. Lubricant composition comprising a) a base oil comprising a1) at least one ethylene oxide homopolymer, a2) at least one ethylene oxide/propylene oxide copolymer. 2. Lubricant composition according to claim 1, characterized in that the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the lubricant composition is 5 wt.% to 45 wt.%. 3. Lubricant composition according to claim 1 or 2, characterized in that the proportion of the base oil a), based on the total weight of the lubricant composition, is 50 wt.% to 99 wt.%, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the lubricant composition is 5 wt.% to 45 wt.%. 4. Lubricant composition according to one or more of the preceding claims, characterized in that the proportion of the base oil a), based on the total weight of the lubricant composition, is 50 wt.% to 99 wt.%, the proportion of the at least one ethylene oxide homopolymer a1) based on the total weight of the base oil is 15 wt.% to 50 wt.%, the proportion of the at least one ethylene oxide/propylene oxide copolymer a2) based on the total weight of the base oil is 50 wt.% to 85 wt.%. 5. Lubricant composition according to one or more of the preceding claims, characterized in that the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%. Lubricant composition according to one or more of the preceding claims, characterized in that the lubricant composition contains: a) 50 wt.% to 99 wt.%, preferably 60 wt.% to 98 wt.%, in particular 70 wt.% to 98 wt.%, based on the total weight of the lubricant composition base oil containing a1) 15 wt.% to 50 wt.% or 10 wt.% to 40 wt.%, preferably 10 wt.% to 30 wt.%, in particular 10 wt.% to 24 wt.%, based on the total weight of the base oil, of at least one ethylene oxide homopolymer, wherein the ethylene oxide homopolymer a1) is preferably prepared starting from ethylene oxide as monomer and/or ethylene glycol as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, more preferably water and/or C1-4 monoalcohol, in particular water, methanol and mixtures thereof, a2) 50 wt.% to 85 wt.%, preferably 76 wt.% to 85 wt.%, based on the total weight of the base oil, of at least one ethylene oxide/propylene oxide copolymer, wherein the ethylene oxide/propylene oxide copolymer a2) preferably contains at least one structural group of the general formula (II) includes, wherein R is selected from H and C1-6 alkyl, preferably from H, C« alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary and wherein the structural group of the general formula (II) is connected via the serpentine bond to a terminal group or a bridging group, wherein the proportion of ethylene oxide homopolymer a1) and ethylene oxide/propylene oxide copolymer a2) taken together, based on the total weight of the base oil, is at least 80 wt.%, for example 80 wt.% to 100 wt.%, preferably 90 wt.% to 100 wt.%, a3) optionally 2 wt.% to 15 wt.%, preferably 5 wt.% to 10 wt.%, based on the total weight of the base oil, of at least one base oil different from a1) and a2), wherein the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is preferably selected from esters, ethers, wherein ethylene oxide homopolymers and Ethylene oxide/propylene oxide copolymers are excluded, and mixtures thereof, b) optionally 0.3 wt.% to 15 wt.%, preferably 0.3 wt.% to 10 wt.%, in particular 0.5 wt.% to 8 wt.%, based on the total weight of the lubricant composition of at least one additive, preferably selected from corrosion inhibitors, antioxidants, metal deactivators, viscosity index improvers, wear protection additives, radical scavengers, UV stabilizers, pour point improvers, friction modifiers, additives for improving the high-pressure properties, adhesion improvers, defoamers and mixtures thereof, c) optionally 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition of at least one thickener, preferably selected from metal simple soaps of elements of the first main group, metal simple soaps of Elements of the second main group, aluminum simple soaps, metal complex soaps of elements of the first main group, metal complex soaps of elements of the second main group, aluminum complex soaps, urea thickeners, metal sulfonate thickeners, inorganic or organic solid lubricants, preferably wax, in particular native wax, polyethylene wax, polypropylene wax, paraffin wax, montan wax, microcrystalline wax, polyamide wax, polyester wax, metal phosphates, metal oxides, metal carbonates, boron nitride, carbon black, graphite, metal chalcogenides, fully fluorinated polymeric substances, fluorine-free polymers, silicon-containing oxides and mixtures of two or more of these thickeners. 7. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide homopolymer a1) is prepared starting from ethylene oxide as monomer and/or ethylene glycol as monomer and starting from a monofunctional initiator compound, in particular water and/or C1-6 monoalcohol, more preferably water and/or C1-4 monoalcohol, in particular water, methanol and mixtures thereof. 8. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide homopolymer a1) has terminal hydrogens and/or terminal C1-6 alkyl groups, more preferably terminal hydrogens and/or terminal C1-6 alkyl groups. 9. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide homopolymer a1) contains only one chain of oxyethylene groups and has terminal hydrogens at both ends. 10. Lubricant composition according to one or more of claims 1 to 6 and 8 to 9, characterized in that the ethylene oxide homopolymer is a compound of the general formula (I) is, wherein R ^a is selected from H, C1-6 alkyl, C2-4 alkanediyl groups, C3-6 alkanetriyl groups and Cs-salkanetetrayl groups, R ^b is selected from H, C1-6 alkyl, provided that when R ^a is a C2-4 alkanediyl group, the ethylene oxide homopolymer comprises 2 fragments when R ^a is a C3-6 alkanetriyl group, the ethylene oxide homopolymer has 3 fragments when R ^a is a Cs-salkanetetrayl group, the ethylene oxide homopolymer 4 Fragments p = an integer from 3 to 20, preferably 4 to 14, in particular 5 to 10. 11 . Lubricant composition according to one or more of the preceding Claims, characterized in that the ethylene oxide homopolymer is a compound of the general formula (I) is, wherein R ^a and R ^b are independently selected from H, C1-6 alkyl, p = an integer from 3 to 20, preferably 4 to 14, in particular 5 to 10 is. 12. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide homopolymer a1) has a molecular weight Mn, measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard, of 150 g/mol to 550 g/mol, preferably of 200 g/mol to 500 g/mol, in particular of 200 g/mol to 400 g/mol. 13. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide homopolymer a1) has a melting point, measured according to DIN EN ISO 11357-3:2018 with a heating rate of 10°K/min., of at most 20°C, for example from -65°C to 20°C, more preferably of at most 10°C, for example from -65°C to 10°C, and/or a glass transition point, measured according to DIN EN ISO 11357-3:2018 with a heating rate of 10°K/min., of at most 20°C, for example from -65°C to 20°C, more preferably of at most 10°C, for example from -65°C to 10°C. 14. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide homopolymer a1) has a kinematic viscosity, determined according to ASTM -D- 7042, September 2014 edition, at 40°C of 3 mm ² /s to 50 mm ² /s, preferably of 10 mm ² /s to 50 mm ² /s, more preferably of 20 mm ² /s to 45 mm ² /s, in particular of 22 to 38 mm ² /s. 15. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide/propylene oxide copolymer a2) has at least one bridging group selected from 1,2-propanediol, 1,2-ethanediol, pentaerythritol and mixtures thereof. 16. Lubricant composition according to one or more of the preceding claims, characterized in that at least 40 wt.%, for example 40 wt.% to 60 wt.%, of the terminal groups of the ethylene oxide/propylene oxide copolymer a2) are alkyl radicals, preferably C1-6 alkyl radicals. 17. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide/propylene oxide copolymer a2) contains at least one structural group of the general formula (II) includes, wherein R is selected from H and C1-6 alkyl, preferably from H, C« alkyl, m = 3 to 20, n = 4 to 85 and wherein the order of the repeating units is arbitrary and wherein the structural group of the general formula (II) is connected to a terminal group or a bridging group via the serpentine bond. 18. Lubricant composition according to one or more of the preceding Claims, characterized in that the ethylene oxide/propylene oxide copolymer a2) is a compound of the general formula (III) wherein R ¹ and R ² are independently selected from H, C1-6 alkyl, preferably from H, C1-4 alkyl, m = 3 to 20, preferably 5 to 20, n = 4 to 85, preferably 5 to 20, where the order of the repeating units is arbitrary; or a compound of the general formula (IV) wherein R ¹ and R ² are independently selected from H and C1-6 alkyl, preferably from H and Ci- ₄ alkyl, R ³ and R ⁴ are independently selected from H and C 1-6 alkyl, preferably from H and C _1-4 alkyl, in particular from H and methyl, each m is independently 3 to 20, each n is independently 4 to 85, wherein the order of the repeating units is arbitrary; or a compound of the general formula (V) wherein R ¹ , R ² , R ³ and R ⁴ are independently selected from H and C1-6 alkyl, preferably from H and _C1-4 alkyl, in particular H, each m is independently 3 to 20, preferably 4 to 20, each n is independently 4 to 85, preferably 4 to 50, wherein the order of the repeating units is arbitrary. 19. Lubricant composition according to one or more of the preceding claims, characterized in that the weight fraction of the oxyethylene repeat units in the ethylene oxide/propylene oxide copolymer a2), in each case based on the total weight of the ethylene oxide/propylene oxide copolymer a2), is at least 20 wt.%, for example 20 wt.% to 90 wt.%, preferably at least 30 wt.%, for example 30 wt.% to 80 wt.%, even more preferably at least 40 wt.%, for example 40 wt.% to 80 wt.%, in particular at least 50 wt.%, for example 50 wt.% to 80 wt.%. 20. Lubricant composition according to one or more of the preceding claims, characterized in that the weight fraction of the oxyethylene repeating units and oxymethylethylene repeating units taken together in the ethylene oxide/propylene oxide copolymer a2), in each case based on the total weight of the ethylene oxide/propylene oxide copolymer a2), is preferably at least 90 wt.%, for example 90 wt.% to 100 wt.%, more preferably at least 95 wt.%, for example 95 wt.% to 100 wt.%. 21. Lubricant composition according to one or more of the preceding claims, characterized in that the ethylene oxide/propylene oxide copolymer has a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 500 g/mol to 25,000 g/mol, preferably of 1,500 g/mol to 25,000 g/mol. 22. Lubricant composition according to one or more of the preceding claims, characterized in that the lubricant composition contains at least one ethylene oxide homopolymer a1) with a molecular weight Mn measured according to DIN 55672-1:2016-03 with THF as solvent and polystyrene as calibration standard of 200 g/mol to 400 g/mol, in combination with at least one ethylene oxide/propylene oxide copolymer a2) with a molecular weight Mn measured according to DIN 55672-1:2016-03 of 1500 g/mol to 25,000 g/mol. 23. Lubricant composition according to one or more of the preceding claims, characterized in that the lubricant composition contains no water or water only in a proportion of less than 10 wt.%, for example from 0 wt.% to 10 wt.%, preferably from 0.1 wt.% to 8 wt.%, in particular from 0.1 wt.% to 6 wt.%, based on the total weight of the lubricant composition, wherein the proportion of water is determined coulometrically according to Karl Fischer in accordance with DIN 51777:2016-08. 24. Lubricant composition according to one or more of the preceding claims, characterized in that the base oil a3) different from the ethylene oxide homopolymer a1) and the ethylene oxide/propylene oxide copolymer a2) is selected from esters, ethers, excluding ethylene oxide homopolymers and ethylene oxide/propylene oxide copolymers, and mixtures thereof. 25. Lubricant composition according to one or more of the preceding claims, characterized in that the lubricant composition is designed as a lubricating oil and has a kinematic viscosity, determined according to ASTM-D-7042, September 2014 edition, at 40°C of 20 mm ² /s to 25,000 mm ² /s, more preferably at 40°C of 20 mm ² /s to 3200 mm ² /s, more preferably at 40°C of 20 mm ² /s to 1500 mm ² /s, more preferably at 40°C of 68 mm ² /s to 680 mm ² /s, in particular at 40°C of 100 mm ² /s to 320 mm ² /s. 26. Lubricant composition according to one or more of the preceding claims, characterized in that the lubricant composition is designed as a lubricating grease and comprises at least one thickener c) in a proportion of 3 wt.% to 45 wt.%, preferably 4 wt.% to 35 wt.%, in particular 5 wt.% to 25 wt.%, based on the total weight of the lubricant composition. 27. Use of a lubricant composition according to one or more of the preceding claims for lubricating tribological systems, preferably selected from gears, in particular industrial gears, gears in electric vehicles, gears that are components of power tools and/or gears of work equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed and/or selected from bearings, in particular bearings in industrial plants, bearings in vehicles, such as automobiles, bearings that are components of power tools and/or bearings of work equipment for processing food, luxury goods, cosmetics, pharmaceuticals and/or animal feed.