WO2019145287A1

WO2019145287A1 - Polymeric-inorganic nanoparticle compositions, manufacturing process thereof and their use as lubricant additives

Info

Publication number: WO2019145287A1
Application number: PCT/EP2019/051480
Authority: WO
Inventors: Stephan Wieber; Christofer Philipp KRONSCHNABL; Can Metehan TURHAN; Sofia SIRAK; Daniel Ness; Günter Schmitt; Roland WILKENS; Jeannette HILF; Maximilian CORNELIUS
Original assignee: Evonik Oil Additives GmbH
Current assignee: Evonik Oil Additives GmbH
Priority date: 2018-01-23
Filing date: 2019-01-22
Publication date: 2019-08-01
Anticipated expiration: 2020-07-23

Abstract

The invention relates to polymeric-inorganic nanoparticle compositions and preparation processes thereof. The invention also relates to an additive and lubricant composition comprising these polymeric-inorganic nanoparticle composition, as well as to the use of these polymeric-inorganic nanoparticle compositions in an oil lubricant formulation to improve tribological performance, in particular to improve extreme pressure performance on metal parts.

Description

Polymeric-inorganic nanoparticle compositions, manufacturing process thereof and

their use as lubricant additives

TECHNICAL FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION

The present invention relates to the field of lubrication. Lubricants are compositions that reduce friction between surfaces. In addition to allowing freedom of motion between two surfaces and reducing mechanical wear of the surfaces, a lubricant also may inhibit corrosion of the surfaces and/or may inhibit damage to the surfaces due to heat or oxidation. Examples of lubricant compositions include, but are not limited to, engine oils, transmission fluids, gear oils, industrial lubricating oils, greases and metalworking oils.

Lubricants typically contain a base fluid and variable amounts of additives. Some additives in the lubricant formulation are used to reduce friction and wear between the contacts, which is important energy efficiency and durability of the device that is being lubricated.

In recent years, there has been a growing interest in the use of solid inorganic nanoparticles in lubricant formulations. These particles are especially useful to achieve boundary lubrication and keep surfaces separated. Studies have shown that the addition of nanoparticles can drastically improve wear and friction performance (Zhou et at, Tribolology Letters 8, 213-218 (2000); Qiu et at. J. Tribol. 123 (3) 441-443 (2001 ).

However, creating a stable dispersion of nanoparticles is problematic. Most untreated inorganic nanoparticles form poor dispersions in oil or non-polar environments. Furthermore, the poor dispersion and weak forces of the particles draw particles together causing agglomeration. These particle agglomerates will lead to sedimentation that is unwanted and ineffective for the formulation.

In order to prevent this sedimentation and enhance dispersion, several techniques have been employed. These techniques include for instance the use of a dispersant moiety in the oil blend. By adding a dispersant moiety to an oil formulation, dispersion of nanoparticles can be improved. One problem with the use of dispersant is that a careful equilibrium of dispersant to particle must exist or the dispersion will fall apart. Heat, energy, and shear forces that are present in a working machine or part can easily break this equilibrium. The disruption of the equilibrium will lead to sedimentation and agglomeration of particles. Furthermore, dispersant moieties are not suited well for non-polar environments. Typically, more polar base fluids need to be added so that the dispersant can be compatible. With increasing trends towards more non-polar fluids (Group III or Group IV oils), many dispersants will not work well in oil formulations containing these oils.

DE2530002 A1 relates to a method of improving the lubricating properties of solid lubricants, especially of molybdenum disulphide. The chemical and mechanical grafting of polymers or functional organic or inorganic groups on solids is known. Thus, according to Angew. Makromol. Chemie 28, 31 (1973) polymers grafted on various solid fillers to improve in this way the properties of the fillers. Also, of course, polymers are already mixed with solids for a variety of applications. However, solid lubricants, and especially molybdenum disulphide, have not yet been treated by these methods. The disadvantages are the insufficient stability of the particles in oil and the low stress stability of the dispersion under tribological conditions. The disclosed procedure handles unhealthy and gaseous or at least very volatile compounds and in a very complicated process procedure.

US20140231 145 A1 describes inorganic fullerene-like nanoparticles of tungsten disulphide (IF-WS2) in lubricants with a functionalizing agents, such as amines, silanes, polymers or combinations thereof using state-of the art dispersion technologies. The disadvantage is that the dispersions show poor performance in extreme pressure, such as 4-ball weld tests (DIN 51350 - part 2).

US2017009171 A1 discloses an industrial lubricant composition including an oil base and a phosphorus-based non-chlorine additive. The industrial lubricant also includes at least one inorganic fullerene-like nanoparticle of a metal chalcogenide, a carbon containing compound and a boron containing compound, wherein the inorganic fullerene-like nanoparticle may have a geometry that is a platelet shaped geometry, a spherical shaped geometry, a multi-layered fullerene-like geometry, a tubular-like geometry or a combination thereof. The outer layer of the metal chalcogenide might be functionalized by silanes, amines, monomers, polymer, copolymers and combination thereof. Dispersions will be prepared using state-of- the-art dispersion technologies. The disadvantage is that the dispersions show poor performance in extreme pressure, such as 4-ball weld tests (DIN 51350 - part 2).

WO2014170485 A1 relates to a lubricant composition comprising at least one base oil, at least one dispersant having a weight average molecular weight higher or equal to 2000 Da and 0.01 to 2 wt% metallic nanoparticles, based on the total weight of the lubricant composition, wherein said metallic nanoparticles are concentric polyhedral nanoparticles with multilayered or sheet structure. The dispersant comprises also polyacrylates and derivatives thereof. In order to disperse the metallic nanoparticles, a PIB-succinimide type dispersant is needed.

Extreme pressure additives (EP additives) are additives for lubricants with a role to decrease or prevent welding of the parts exposed to very high pressures, which would cause a huge damage of the machinery. Extreme pressure additives are usually used in applications such as gearboxes. Extreme pressure gear oils perform well over a range of temperatures, speeds and gear sizes to help prevent damage to the gears during starting and stopping of the engine. However, extreme pressure additives are rarely used in motor oils, because the sulfur or chlorine compounds contained in them can react with water and combustion byproducts, forming acids that facilitate corrosion of the engine parts and bearings. Extreme pressure additives typically contain organic sulfur, phosphorus or chlorine compounds, including sulfur-phosphorus and sulfur-phosphorus-boron compounds, which chemically react with the metal surface under high pressure conditions. Under such conditions, small irregularities on the sliding surfaces cause localized flashes of high temperature (300-1000 °C), without significant increase of the average surface temperature. The chemical reaction between the additives and the surface is confined to this area. Extreme pressure additives might be for instance dark inactive sulfurized fat, dark active sulfurized fat, dark active sulfur hydrocarbon, short and medium chain chlorinated alkanes or polysulfides. Current trend in the industry is to lower the content of sulfated ash, phosphorus and sulfur (so called SAPS) to avoid the disadvantages described above.

It was therefore an object of the present invention to provide a lubricant additive which shows improved extreme pressure performances, while maintaining excellent stability over a long period of time in the lubricating oil. In addition, the lubricant additive should show good compatibilities with the different package components, dispersing agents, and other additives in a lubricant formulation and simultaneously also reduce the SAPS content of the formulation to fulfill the industry needs.

BRIEF SUMMARY OF THE INVENTION

After thorough investigation, the inventors of the present invention have surprisingly found that the polymeric-inorganic nanoparticle composition as defined in claim 1 provides improved extreme pressure performance when added to a lubricant composition while being very well-dispersed in the lubrication oil.

A second aspect of the invention is a method for manufacturing the polymeric-inorganic nanoparticle compositions of the invention. A third aspect of the invention is the use of such composition as an additive for a lubricant composition.

A fourth aspect of the invention is a composition - either as additive composition or as ready-to-use lubricant composition - comprising a base oil and the inorganic nanoparticle composition of the invention to improve the extreme pressure performance of moving metal parts of an engine, a gearbox or pump of an automobile, a wind turbine, or a hydraulic system.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of better illustrating the advantages and properties of the claimed polymeric- inorganic nanoparticles object of the invention, some figures are attached as non-limiting examples:

Figure 1 is a bar chart comparing the four ball weld results of the composition according to the invention with prior art compositions.

Figure 2 is a Transmission Electron Microscope (TEM) image of an original intercalation compound of IF-WS2 prepared in isopropanol/water, dispersed and dried.

Figure 3 is a Transmission Electron Microscope (TEM) image of the same intercalation compound of IF-WS2 after ball milling treatment according to the present invention, the image being taken after centrifugation and washing with chloroform.

DETAILED DESCRIPTION OF THE INVENTION

The polymeric-inorganic nanoparticle composition according to the invention

In a first aspect, the invention relates to a polymeric-inorganic nanoparticle composition obtainable by milling a mixture, the mixture comprising one or more intercalation compound (A) and one or more polymer compound (B),

(A) wherein the one or more intercalation compound comprises a metal chalcogenide having molecular formula MX2, where M is a metallic element selected from the group consisting of titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), cadmium (Cd), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), mercury (Hg) and combinations thereof, and X is a chalcogen element selected from the group consisting of sulfur (S), selenium (Se), tellurium (Te), oxygen (O) and combinations thereof, and

(B) wherein the one or more polymer compound is obtainable by polymerizing a monomer composition comprising: a) one or more compounds of formula (I)

wherein R = H or CH₃

where 0 < h < 2

Si(A)h(X)3-h is a silane functional group,

A is a branched or unbranched C1 to C4 alkyl residue,

B is a branched or unbranched, aliphatic, aromatic or mixed aliphatic-aromatic C1 to C30 carbon-based group,

X is selected from H, Cl or a group OY , wherein Y is H or a C1 to C30 branched or unbranched alkyl-, alkenyl-, aryl-, or aralkyl- group, branched or unbranched C2 to C30 alkylether-group or branched or unbranched C2 to C30 alkylpolyether-group or a mixture thereof, and b) one or more alkyl (meth)acrylates, and wherein the weight ratio of the one or more intercalation compound (A) to the one or more polymer compound (B) is 20:1 to 1 :5. Intercalation compound according to the invention (component (A))

The term intercalation compound according to this invention denotes a compound that can be inserted between elements or layers. The intercalation compound typically has a fullerene-like geometry. The core of the fullerene-like geometry may be hollow, solid, amorphous, or a combination thereof. A fullerene-like geometry may also be referred to as having a cage geometry. More specifically, in some embodiments, an intercalation compound having an inorganic fullerene- like geometry may be a cage geometry that is hollow or solid at its core and layered at its periphery. For example, the intercalation compound having the inorganic fullerene like geometry may be a single layer or double layered structure. The intercalation compound is not limited on only single layer or double layered structures, as the intercalation compound may have any number of layers. These structures are also referred to in the art as being nested layer structures.

In a preferred embodiment, the inorganic fullerene-like geometry of the intercalation compound may be of spherical, near spherical, polyhedral, elongated, rod-, cube-, sheet- or tube-like geometry or a mixture thereof, with or without a hollow core.

The one or more intercalation compound may have any inorganic composition meeting the formula MX_å, where M is a metallic element selected from the group consisting of titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), cadmium (Cd), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Ft), gold (Au), mercury (Hg) and combinations thereof, and X is a chalcogen element selected from the group consisting of sulfur (S), selenium (Se), tellurium (Te), oxygen (O) and combinations thereof.

According to the present invention, the intercalation compound is a microscopic particle with at least one dimension being between 2 and 500 nm, preferably between 10 and 300 nm and more preferably between 30 and 200 nm (determined using transmission electron microscopy, TEM). This particle can either be of individual character or be present in an aggregated and/or agglomerated structure. In these latter cases, the size of the primary particle is between the aforementioned sizes in at least one dimension. The above dimensions are provided for illustrative purposes only, and are not intended to limit the present disclosure.

The intercalation compound having the metal chalcogenide composition, e.g. WS₂, and the fullerene-like geometry may be produced via sulfidization of tungsten oxide nanoparticles in reduction atmosphere in a fluidized bed reactor. The intercalation compound may be formed in accordance with at least one of the methods disclosed in U.S. Pat. No. 6,217,843, U.S. Pat. No. 6,710,020, U.S. Pat. No. 6,841 , 142, U.S. Pat. No. 7,018,606 and U.S. Pat. No. 7,641 ,886, which are each incorporated herein in their entirety. The methods disclosed in the aforementioned patents are only some examples of methods that are suitable for forming the intercalation compound. Any method may be employed for forming the above-described intercalation compound, as long as the compound formed has a fullerene-like geometry.

In another preferred embodiment, the intercalation compound is a nanostructured compound that includes a multi-layered fullerene-like nano-structure composed of a plurality of layers each having a metal chalcogenide composition that has a molecular formula of MX2 (M = W and X = S) , preferably with a spherical shape.

Polymer compound (component (B))

In a preferred embodiment of the invention, the compound of formula (I) is selected from 3- (Triethoxysilyl)propyl methacrylate, 3-(Trimethoxysilyl)propyl methacrylate, 3-(Trichlorosilyl)propyl methacrylate, even more preferably 3-(Trimethoxysilyl)propyl methacrylate.

According to the present invention, it is preferred that the one or more alkyl (meth)acrylates b) is an alkyl (meth)acrylate having an alkyl group comprising from 1 to 40 carbon atoms. The resulting one or more polymer B has preferably a weight-average molecular weight (M_w) of 5,000 to 150,000 g/mol, more preferably 10,000 to 120,000 g/mol, even more preferably 10,000 to 80,000 g/mol, most preferably 10,000 to 60,000 g/mol.

In another preferred embodiment of the invention, the above defined monomer composition may further comprise one or more components c) prepared by the reaction of one or more ester of (meth)acrylic acid and one or more hydroxylated hydrogenated polybutadiene having a number- average molecular weight (M_n) of 500 to 10,000 g/mol. The corresponding reaction product component c) can also be referred to as macromonomers (MM) in the context of this invention. In this context, the polymer (B) of this invention comprises a first polymer, which is also referred to as backbone or main chain, and a multitude of further polymers which are referred to as side chains and are bonded covalently to the backbone. In the present case, the backbone of the polymer is formed by the interlinked unsaturated groups of the mentioned (meth)acrylic acid esters. The alkyl groups and the hydrogenated polybutadiene chains of the (meth)acrylic esters form the side chains of the polymer. The reaction product of one or more additional ester of (meth)acrylic acid and one or more hydroxylated hydrogenated polybutadiene having a number-average molecular weight of 500 to 10,000 g/mol is also referred in the present invention as macromonomer. If these monomers are included, they are also regarded as macromonomers for the purpose of calculating the below- mentioned degree of branching. According to the present invention, the one or more polymer (B) prepared with a monomer composition comprising the components a), b) and c), and optionally d), may preferably have a weight-average molecular weight (M_w) of 10,000 to 1 ,000,000 g/mol. Polymers of different weight- average molecular weight may be used for different applications, for example as additives for engine oils, transmission fluids and tractor oils. Preferably, the weight-average molecular weight (M_w) of the polymers (B) prepared with a monomer composition comprising the components a), b) and c), and optionally d), is in the range of 10,000 to 1 ,000,000 g/mol, more preferably 50,000 to 1 ,000,000 g/mol, even more preferably 200,000 to 1 ,000,000 g/mol, most preferably 300,000 to 800,000 g/mol.

In the present invention, molecular weights of the polymers were determined by gel permeation chromatography (GPC) using commercially available polymethylmethacrylate (PMMA) standards. The determination is effected by GPC with THF as eluent (flow rate: 1 mL/min; injected volume: 100 bL).

The number-average molecular weight M_n of the macromonomer is determined by gel permeation chromatography (GPC) using commercially available polybutadiene standards. The determination is effected to DIN 55672-1 by GPC with THF as eluent.

The one or more polymer (B) prepared with a monomer composition comprising the components a), b) and c) can be characterized on the basis of its molar degree of branching ("f-branch"). The molar degree of branching refers to the percentage in mol% of macromonomers (component c)) used, based on the total molar amount of all the monomers in the monomer composition. The molar amount of the macromonomers used is calculated on the basis of the number-average molecular weight M_n of the macromonomers. The calculation of the molar degree of branching is described in detail in WO 2007/003238 A1 , especially on pages 13 and 14, to which reference is made here explicitly.

Preferably, the one or more polymer (B) prepared with a monomer composition comprising the components a), b) and c) have a molar degree of branching fbranc_h of 0.1 to 6 mol%, more preferably 1 to 4 mol% and most preferably 1.5 to 3 mol%.

The term "(meth)acrylic acid" refers to acrylic acid, methacrylic acid and mixtures of acrylic acid and methacrylic acid; methacrylic acid being preferred. The term "(meth)acrylate" refers to esters of acrylic acid, esters of methacrylic acid or mixtures of esters of acrylic acid and methacrylic acid; esters of methacrylic acid being preferred. Macromonomer (component c))

The one or more hydroxylated hydrogenated polybutadienes used in the preparation of component c) in accordance with the invention have a number-average molecular weight M_n of 500 g/mol to 10,000 g/mol. Because of their high molecular weight, the hydroxylated hydrogenated polybutadienes can also be referred to as macroalcohols (MA) in the context of this invention. The corresponding esters of (meth)acrylic acid can also be referred to as macromonomers in the context of this invention.

Component c) may comprise a single type of macromonomer or may comprise a mixture of different macromonomers based on different macroalcohols.

By combining one or more macromonomers based on a macroalcohol having number-average molecular weight of 500 g/mol to 10,000 g/mol with one or more alkyl(meth)acrylates b) and the one or more compound a) of formula (I) according to the invention, a polymer (B) can be obtained which when combined with the nanoparticles (A) offers a stable well-dispersed polymeric-inorganic nanoparticle composition.

The hydroxylated hydrogenated polybutadiene may be a single polybutadiene with a single number- average molecular weight or it may be a mixture of different polybutadienes having different number- average molecular weights.

Preferably, the monomer composition comprises as component c) 20 to 60 % by weight, more preferably 20 to 50 % by weight, even more preferably 20 to 45 % by weight, most preferably 20 to 35 % by weight of one or more ester of (meth)acrylic acid and one or more hydroxylated hydrogenated polybutadiene having a number-average molecular weight of 500 g/mol to 10,000 g/mol. If these monomers are included, they are also regarded as macromonomers for the purpose of calculating the above-mentioned degree of branching.

In a preferred embodiment, the one or more hydroxylated hydrogenated polybutadiene for use as component c) has a number-average molecular weight of 1 ,500 to 2,100 g/mol, preferably 1 ,800 to 2, 100 g/mol, more preferably 1 ,900 to 2, 100 g/mol.

In another preferred embodiment, the one or more hydroxylated hydrogenated polybutadiene for use as component c) has a number-average molecular weight of 3,500 to 7,000 g/mol, preferably 4,000 to 6,000 g/mol, more preferably 4,500 to 5,000 g/mol.

In another preferred embodiment, component c) may be one macromonomer prepared using one or more macroalcohols having different molecular weights, the first macroalcohol having a number- average molecular weight of 1 ,500 to 2, 100 g/mol, more preferably 1 ,800 to 2, 100 g/mol, most preferably 1 ,900 to 2, 100 g/mol, and the second macroalcohol having a number-average molecular weight of 3,500 to 7,000 g/mol, preferably 4,000 to 6,000 g/mol, more preferably 4,500 to 5,000 g/mol. Component c) may also comprise a mixture of two macromonomers, the first macromonomer being prepared with a macroalcohol having a number-average molecular weight of 1 ,500 to 2,100 g/mol, more preferably 1 ,800 to 2,100 g/mol, most preferably 1 ,900 to 2,100 g/mol, and the second macromonomer being prepared with a macroalcohol having a number-average molecular weight of 3,500 to 7,000 g/mol, preferably 4,000 to 6,000 g/mol, more preferably 4,500 to 5,000 g/mol.

According to a preferred embodiment of the present invention, by combining two macromonomers of different number-average molecular weights, the weight proportion of the lower molecular weight macromonomer to the higher molecular weight macromonomer is preferably one or more, more preferably 1.5 to 15, even more preferably 2 to 7, most preferably 3 to 6.

In a preferred embodiment, the one or more hydroxylated hydrogenated polybutadiene is a monohydroxylated hydrogenated polybutadiene, preferably a hydroxyethyl-terminated or hydroxypropyl- terminated hydrogenated polybutadiene.

In another preferred embodiment of the invention, the one or more ester of (meth)acrylic acid of the component c) used for the preparation of the polymer (B) is methyl (meth)acrylate or ethyl (meth)acrylate.

Preferably, the one or more hydroxylated hydrogenated polybutadiene has a hydrogenation level of at least 99%. An alternative measure of the hydrogenation level which can be determined on the polymer of the invention is the iodine number. The iodine number refers to the number of grams of iodine which can be added onto 100 g of polymer. Preferably, the polymer of the invention has an iodine number of not more than 5 g of iodine per 100 g of polymer. The iodine number is determined by the Wijs method according to DIN 53241-1 : 1995-05.

Preferred hydroxylated hydrogenated polybutadienes can be obtained according to GB 2270317.

As used herein, the term “hydroxylated hydrogenated polybutadiene” refers to a hydrogenated polybutadiene that comprises one or more hydroxyl group. The hydroxylated hydrogenated polybutadiene may further comprise additional structural units, such as polyether groups derived from the addition of alkylene oxides to a polybutadiene or a maleic anhydride group derived from the addition of maleic anhydride to a polybutadiene. These additional structural units may be introduced into the polybutadiene when the polybutadiene is functionalized with hydroxyl groups. Preference is given to monohydroxylated hydrogenated polybutadienes. More preferably, the hydroxylated hydrogenated polybutadiene is a hydroxyethyl- or hydroxypropyl-terminated hydrogenated polybutadiene. Particular preference is given to hydroxypropyl-terminated polybutadienes.

These monohydroxylated hydrogenated polybutadienes can be prepared by first converting butadiene monomers by anionic polymerization to polybutadiene. Subsequently, by reaction of the polybutadiene monomers with an alkylene oxide, such as ethylene oxide or propylene oxide, a hydroxy-functionalized polybutadiene can be prepared. The polybutadiene may also be reacted with more than one alkylene oxide units, resulting in a polyether-polybutadiene block copolymer having a terminal hydroxyl group. The hydroxylated polybutadiene can be hydrogenated in the presence of a suitable transition metal catalyst.

These monohydroxylated hydrogenated polybutadienes can also be selected from products obtained by hydroboration of (co)polymers of having a terminal double bond (e.g. as described in US Patent No. 4,316,973); maleic anhydride-ene-amino alcohol adducts obtained by an ene reaction between a (co)polymer having a terminal double bond and maleic anhydride with an amino alcohol; and products obtained by hydroformylation of a (co)polymer having a terminal double bond, followed by hydrogenation (e.g. as described in JP Publication No. S63-175096).

The macromonomers for use in accordance with the invention can be prepared by transesterification of alkyl (meth)acrylates. Reaction of the alkyl (meth)acrylate with the hydroxylated hydrogenated polybutadiene forms the ester of the invention. Preference is given to using methyl (meth)acrylate or ethyl (meth)acrylate as reactant.

This transesterification is widely known. For example, it is possible for this purpose to use a heterogeneous catalyst system, such as lithium hydroxide/calcium oxide mixture (LiOH/CaO), pure lithium hydroxide (LiOH), lithium methoxide (LiOMe) or sodium methoxide (NaOMe) or a homogeneous catalyst system such as isopropyl titanate (Ti(OiPr)₄) or dioctyltin oxide (Sn(OCt)₂0). The reaction is an equilibrium reaction. Therefore, the low molecular weight alcohol released is typically removed, for example by distillation.

In addition, the macromonomers can be obtained by a direct esterification proceeding, for example, from (meth)acrylic acid or (meth)acrylic anhydride, preferably under acidic catalysis by p- toluenesulfonic acid or methanesulfonic acid, or from free methacrylic acid by the DCC method (dicyclohexylcarbodiimide).

Furthermore, the present hydroxylated hydrogenated polybutadiene can be converted to an ester by reaction with an acid chloride such as (meth)acryloyl chloride. Preferably, in the above-detailed preparations of the esters of the invention, polymerization inhibitors are used, for example the 4-hydroxy-2,2,6,6-tetramethylpiperidinooxyl radical and/or hydroquinone monomethyl ether.

AlkvKmetfOacrylates (component b)1

The term “C1-40 alkyl(meth)acrylates” refers to esters of (meth)acrylic acid and straight chain or branched alcohols having 1 to 40 carbon atoms. The term encompasses individual (meth)acrylic esters with an alcohol of a particular length, and likewise mixtures of (meth)acrylic esters with alcohols of different lengths.

According to the present invention it is preferred that each of the one or more alkyl (meth)acrylate monomers b) independently is b1 ) of formula (II):

wherein R is hydrogen or methyl, R¹ means a linear, branched or cyclic alkyl residue with 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, and more preferably 1 to 3 carbon atoms, or b2) of formula (III):

wherein R is hydrogen or methyl, R² means a linear, branched or cyclic alkyl residue with 9 to 15 carbon atoms, preferably 12 to 15 carbon atoms, and more preferably 12 to 14 carbon atoms, or b3) of formula (IV):

wherein R is hydrogen or methyl, R³ means a linear, branched or cyclic alkyl residue with 16 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 16 to 20 carbon atoms. That is to say, according to the invention, it is preferred that the one or more alkyl (meth)acrylates as component b) are selected from b1 ), b2), b3) or a mixture thereof.

According to the invention it is particularly preferred that each of the one or more monomers according to formula (II) is independently selected from the group consisting of (meth)acrylates derived from saturated alcohols, preferably methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cycloalkyl (meth)acrylates, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, heptyl (meth)acrylate, 2-tert-butylheptyl (meth)acrylate, n-octyl (meth)acrylate and 3-isopropylheptyl (meth)acrylate, the most preferred monomer according to formula (II) is methyl methacrylate.

According to the invention it is also particularly preferred that each of the one or more monomers according to formula (III) is independently selected from the group consisting of nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, 5- methylundecyl (meth)acrylate, n-dodecyl (meth)acrylate, 2-methyldodecyl (meth)acrylate, tridecyl (meth)acrylate, 5-methyltridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, oleyl (meth)acrylate, cycloalkyl (meth)acrylates, cyclohexyl (meth)acrylate having a ring substituent, tert-butylcyclohexyl (meth)acrylate, trimethylcyclohexyl (meth)acrylate, bornyl (meth)acrylate and isobornyl (meth)acrylate.

According to the invention, it is also particularly preferred that each of the one or more monomers according to formula (IV) is independently selected from the group consisting of hexadecyl (meth)acrylate, 2-methylhexadecyl (meth)acrylate, heptadecyl (meth)acrylate, 5- isopropylheptadecyl (meth)acrylate, 4-tert-butyloctadecyl (meth)acrylate, 5-ethyloctadecyl (meth)acrylate, 3-isopropyloctadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, cetyleicosyl (meth)acrylate, stearyleicosyl (meth)acrylate, docosyl (meth)acrylate, behenyl (meth)acrylate, eicosyltetratriacontyl (meth)acrylate, cycloalkyl (meth)acrylates, 2,4,5-tri-t-butyl-3-vinylcyclohexyl (meth)acrylate, and 2,3,4,5-tetra-t- butylcyclohexyl (meth)acrylate.

Preferably, the C1-40 alkyl(meth)acrylates include a mixture of C-i-8 alkyl (meth)acrylates and C9-15 alkyl (meth)acrylates, more preferably is a C12-14 alkyl (meth)acrylate.

The term “C1-8 alkyl(meth)acrylates” refers to esters of (meth)acrylic acid and straight chain or branched alcohols having 1 to 8 carbon atoms. The term encompasses individual (meth)acrylic esters with an alcohol of a particular length, and likewise mixtures of (meth)acrylic esters with alcohols of different lengths. Suitable C1-8 alkyl (meth)acrylates include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cycloalkyl (meth)acrylates, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, heptyl (meth)acrylate, 2-tert-butylheptyl (meth)acrylate, n-octyl (meth)acrylate and 3-isopropylheptyl (meth)acrylate, the most preferred monomer according to formula (II) is methyl methacrylate.

Particularly preferred C1-8 alkyl (meth)acrylates are methyl (meth)acrylate and n-butyl (meth)acrylate; methyl methacrylate and n-butyl methacrylate are especially preferred.

The term “C9-15 alkyl (meth)acrylates” refers to esters of (meth)acrylic acid and straight chain or branched alcohols having 9 to 15 carbon atoms. The term encompasses individual (meth)acrylic esters with an alcohol of a particular length, and likewise mixtures of (meth)acrylic esters with alcohols of different lengths.

Suitable C9-15 alkyl (meth)acrylates include, for example, nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, 5-methylundecyl (meth)acrylate, n-dodecyl (meth)acrylate, 2-methyldodecyl (meth)acrylate, tridecyl (meth)acrylate, 5-methyltridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, oleyl (meth)acrylate, cycloalkyl (meth)acrylates, cyclohexyl (meth)acrylate having a ring substituent, tert-butylcyclohexyl (meth)acrylate, trimethylcyclohexyl (meth)acrylate, bornyl (meth)acrylate and isobornyl (meth)acrylate.

Particularly preferred C9-15 alkyl (meth)acrylates are (meth)acrylic esters of a linear C12-14 alcohol mixture (C12-14 alkyl (meth)acrylate).

The term “C16-40 alkyl(meth)acrylates” refers to esters of (meth)acrylic acid and straight chain or branched alcohols having 16 to 40 carbon atoms. The term encompasses individual (meth)acrylic esters with an alcohol of a particular length, and likewise mixtures of (meth)acrylic esters with alcohols of different lengths.

Suitable C16-40 alkyl (meth)acrylates include, for example, hexadecyl (meth)acrylate, 2- methylhexadecyl (meth)acrylate, heptadecyl (meth)acrylate, 5-isopropylheptadecyl (meth)acrylate, 4-tert-butyloctadecyl (meth)acrylate, 5-ethyloctadecyl (meth)acrylate, 3-isopropyloctadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, cetyleicosyl (meth)acrylate, stearyleicosyl (meth)acrylate, docosyl (meth)acrylate, behenyl (meth)acrylate, eicosyltetratriacontyl (meth)acrylate, cycloalkyl (meth)acrylates, 2,4,5-tri-t-butyl-3- vinylcyclohexyl (meth)acrylate, and 2,3,4,5-tetra-t-butylcyclohexyl (meth)acrylate. Preferably, the monomer composition to prepare the polymer (B) comprises as component a) 1 to 60 % by weight of one or more compound of formula (I) and, as component b), 0 to 20 % by weight of one or more C-i-8 alkyl (meth)acrylates b1 ) and 20 to 99 % by weight of one or more C9-15 alkyl (meth)acrylates b2); more preferably as component a) 3 to 40 % by weight of one or more compound of formula (I) and as component b) 0 to 10 % by weight of one or more C1-8 alkyl (meth)acrylates b1 ) and 50 to 97 % by weight of one or more C9-15 alkyl (meth)acrylates b2); most preferably as component a) 10 to 30 % by weight of one or more compound of formula (I) and as component b) 0 to 5 % by weight of one or more C1-8 alkyl (meth)acrylates b1 ) and 65 to 90 % by weight of one or more C9-15 alkyl (meth)acrylates b2), based on the total weight of the monomer composition.

In one preferred embodiment, the monomer composition to prepare the polymer (B) comprises as component a) 1 to 60 % by weight 3-(Methacryloyloxy)propyl]trimethoxysilane, and as component b) 40 to 99 % by weight Lauryl (meth)acrylate, more preferably as component a) 3 to 40 % by weight 3-(Methacryloyloxy)propyl]trimethoxysilane and as component b) 60 to 97 % by weight Lauryl (meth)acrylate; most preferably as component a) 10 to 30 % by weight 3-

(Methacryloyloxy)propyl]trimethoxysilane and as component b) 70 to 90 % by weight Lauryl (meth)acrylate), based on the total weight of the monomer composition.

Additional monomers

In another embodiment of the invention, the monomer composition to prepare the polymer (B) may comprise additional monomers (component d)) in addition to the components a) and b) or in addition to the components a), b) and c).

Additional monomers d) and combinations thereof, which can be used in accordance with the invention, are selected from the group consisting of: hydroxyalkyl (meth)acrylates like 3-hydroxypropyl (meth)acrylate, 3,4-dihydroxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2 hydroxypropyl (meth)acrylate, 2,5-dimethyl-1 ,6-hexanediol (meth)acrylate, 1 ,10 decanediol (meth)acrylate; aminoalkyl (meth)acrylates and aminoalkyl (meth)acrylamides like N-(3-dimethyl- aminopropyl)methacrylamide, 3-diethylaminopentyl (meth)acrylate, 3-dibutyl-aminohexadecyl (meth)acrylate; nitriles of (meth)acrylic acid and other nitrogen-containing (meth)acrylates like N (methacryloyloxyethyl)diisobutylketimine, N-(methacryloyloxyethyl)dihexadecyl-ketimine,

(meth)acryloylamidoacetonitrile, 2-methacryloyloxyethylmethylcyanamide, cyanomethyl (meth)acrylate; aryl (meth)acrylates like benzyl (meth)acrylate or phenyl (meth)acrylate, where the acryl residue in each case can be unsubstituted or substituted up to four times; carbonyl-containing (meth)acrylates like 2-carboxyethyl (meth)acrylate, carboxymethyl (meth)acrylate, oxazolidinylethyl (meth)acrylate, N-methyacryloyloxy)-formamide, acetonyl (meth)acrylate, N- methacryloylmorpholine, N-methacryloyl-2 pyrrolidinone, N-(2-methyacryloxyoxyethyl)-2- pyrrolidinone, N-(3-methacryloyloxy-propyl)-2-pyrrolidinone, N-(2-methyacryloyloxypentadecyl(-2- pyrrolidinone, N (3 methacryloyloxyheptadecyl-2-pyrrolidinone;

(methacrylates of ether alcohols like tetrahydrofurfuryl (meth)acrylate, methoxyethoxyethyl (meth)acrylate, 1-butoxypropyl (meth)acrylate, cyclohexyloxyethyl (meth)acrylate, propoxyethoxyethyl (meth)acrylate, benzyloxyethyl (meth)acrylate, furfuryl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2- ethoxy-2-ethoxyethyl (meth)acrylate, 2-methoxy-2-ethoxypropyl (meth)acrylate, ethoxylated (meth)acrylates, 1-ethoxybutyl (meth)acrylate, methoxyethyl (meth)acrylate, 2-ethoxy-2-ethoxy-2- ethoxyethyl (meth)acrylate, esters of (meth)acrylic acid and methoxy polyethylene glycols;

(methacrylates of halogenated alcohols like 2,3-dibromopropyl (meth)acrylate, 4 bromophenyl (meth)acrylate, 1 ,3-dichloro-2-propyl (meth)acrylate, 2-bromoethyl (meth)acrylate, 2-iodoethyl (meth)acrylate, chloromethyl (meth)acrylate; oxiranyl (meth)acrylate like 2, 3-epoxybutyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, 10,11 epoxyundecyl (meth)acrylate, 2,3-epoxycyclohexyl (meth)acrylate, oxiranyl (meth)acrylates such as 10,11-epoxyhexadecyl (meth)acrylate, glycidyl (meth)acrylate; phosphorus-, boron- and/or silicon-containing (meth)acrylates like 2-(dimethyl-phosphato)propyl (meth)acrylate, 2-(ethylphosphito)propyl (meth)acrylate, 2 dimethylphosphinomethyl (meth)acrylate, dimethylphosphonoethyl (meth)acrylate, diethylmethacryloyl phosphonate, dipropylmethacryloyl phosphate, 2 (dibutylphosphono)ethyl (meth)acrylate, 2,3-butylenemethacryloylethyl borate, methyldiethoxymethacryloylethoxysiliane, diethylphosphatoethyl (meth)acrylate; sulfur-containing (meth)acrylates like ethylsulfinylethyl (meth)acrylate, 4-thio-cyanatobutyl (meth)acrylate, ethylsulfonylethyl (meth)acrylate, thiocyanatomethyl (meth)acrylate, methylsulfinylmethyl (meth)acrylate, bis(methacryloyloxyethyl) sulfide; heterocyclic (meth)acrylates like 2-(1-imidazolyl)ethyl (meth)acrylate, 2-(4-morpholinyl)ethyl (meth)acrylate and 1-(2-methacryloyloxyethyl)-2-pyrrolidone; maleic acid and maleic acid derivatives such as mono- and diesters of maleic acid, maleic anhydride, methylmaleic anhydride, maleinimide, methylmaleinimide; fumaric acid and fumaric acid derivatives such as, for example, mono- and diesters of fumaric acid; vinyl halides such as, for example, vinyl chloride, vinyl fluoride, vinylidene chloride and vinylidene fluoride; vinyl esters like vinyl acetate; vinyl monomers containing aromatic groups like styrene, substituted styrenes with an alkyl substituent in the side chain, such as alpha-methylstyrene and alpha-ethylstyrene, substituted styrenes with an alkyl substituent on the ring such as vinyltoluene and p-methylstyrene, halogenated styrenes such as monochlorostyrenes, dichlorostyrenes, tribromostyrenes and tetrabromostyrenes; most preferred vinyl monomers are selected from the group consisting of styrene monomers having from 8 to 17 carbon atoms, vinyl esters having from 1 to 1 1 carbon atoms in the acyl group, vinyl ethers having from 1 to 10 carbon atoms in the alcohol group, dispersing oxygen- and/or nitrogen-functionalized monomers, heterocyclic (meth)acrylates, heterocyclic vinyl compounds, monomers containing a covalently bonded phosphorous atom, monomers containing epoxy groups and monomers containing halogens. Suitable styrene monomers having from 8 to 17 carbon atoms are selected from the group consisting of styrene, substituted styrenes having an alkyl substituent in the side chain, for example alpha-methylstyrene and alpha-ethylstyrene, substituted styrenes having an alkyl substituent on the ring, such as vinyltoluene and para-methylstyrene, halogenated styrenes, for example monochlorostyrenes, dichlorostyrenes, tribromostyrenes and tetrabromostyrenes, nitrostyrene; styrene being preferred. heterocyclic vinyl compounds like 2-vinylpyridine, 3-vinylpyridine, 2-methyl-5-vinylpyridine, 3- ethyl-4-vinylpyridine, 2,3-dimethyl-5-vinylpyridine, vinylpyrimidine, vinylpiperidine, 9- vinylcarbazole, 3-vinylcarbazole, 4-vinylcarbazole, 1-vinylimidazole, 2-methyl-1-vinylimidazole, N-vinylpyrrolidone, 2-vinylpyrrolidone, N-vinylpyrrolidine, 3-vinylpyrrolidine, N-vinylcaprolactam, N-vinylbutyrolactam, vinyloxolane, vinylfuran, vinylthiophene, vinylthiolane, vinylthiazoles and hydrogenated vinylthiazoles, vinyloxazoles and hydrogenated vinyloxazoles; vinyl and isoprenyl ethers; methacrylic acid and acrylic acid.

In a preferred aspect of the invention, the monomer composition to prepare the polymer (B) comprises as component a) 1 to 20 % by weight of one or more compound of formula (I) and as component b) 20 to 80 % by weight of one or more alkyl (meth)acrylates, and as component c) 0 to 60 % by weight of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene and as component d) 0 to 70 % by weight of one or more additional monomers, based on the total weight of the monomer composition. Preferably, the amounts of components a) to d) of the monomer composition to prepare the polymer (B) add up to 100 % by weight.

In a preferred aspect of the invention, the monomer composition to prepare the polymer (B) comprises:

a) 1 to 20 % by weight, preferably 1 to 15 % by weight, more preferably 2 to 10 % by weight, of one or more compound of formula (I), based on the total weight of the monomer composition,

b) 20 to 60 % by weight of one or more C1-8 alkyl (meth)acrylates (b1 ) and 1 to 40 % by weight of one or more C9-15 alkyl (meth)acrylates (b2), preferably 30 to 60 % by weight of one or more C1-8 alkyl (meth)acrylates (b1 ) and 1 to 20 % by weight of one or more C9-15 alkyl (meth)acrylates (b2), more preferably 40 to 60 % by weight of one or more C1- 8 alkyl (meth)acrylates (b1 ) and 2 to 10 % by weight of one or more C9-15 alkyl (meth)acrylates (b2), based on the total weight of the monomer composition, c) 0 to 60 % by weight, preferably 10 to 50 % by weight, more preferably 20 to 40 % by weight, of one or more components c), prepared by the reaction of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene, based on the total weight of the monomer composition, and

d) 0 to 70 % by weight, preferably 2 to 50 % by weight, more preferably 10 to 25 % by weight, of one or more additional monomers d), based on the total weight of the monomer composition,

wherein the amount of all monomers of the monomer composition sum up to 100 % by weight.

Preferably, the monomer composition to prepare the polymer (B) comprises as component a) 1 to 20 % by weight of one or more compound of formula (I) and as component b) 20 to 60 % by weight of one or more C-i-8 alkyl (meth)acrylates b1 ) and 1 to 40 % by weight of one or more C9-15 alkyl (meth)acrylates b2), and as component c) 5 to 60 % by weight of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene and as component d) 0 to 70 % by weight of one or more additional monomers, more preferably as component a) 1 to 15 % by weight of one or more compound of formula (I) and as component b) 30 to 60 % by weight of one or more C1-8 alkyl (meth)acrylates b1 ) and 1 to 20 % by weight of one or more C9-15 alkyl (meth)acrylates b2), and as component c) 10 to 50 % by weight of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene and as component d) 2 to 50 % by weight of one or more additional monomers, most preferably as component a) 2 to 10 % by weight of one or more compound of formula (I) and as component b) 40 to 60 % by weight of one or more C1-8 alkyl (meth)acrylates b1 ) and 2 to 10 % by weight of one or more C9-15 alkyl (meth)acrylates b2), and as component c) 20 to 40 % by weight of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene and as component d) 10 to 25 % by weight of one or more additional monomers, based on the total weight of the monomer composition.

Preferably, the additional monomers (component d)) include styrene monomers having from 8 to 17 carbon atoms and optionally dispersing oxygen- and/or nitrogen-functionalized monomers.

Preferably, the additional monomers are styrene monomers having from 8 to 17 carbon atoms.

Preferably, the amounts of components a) to d) of the monomer composition to prepare the polymer (B) add up to 100 % by weight.

Preferable monomer compositions

According to a preferred embodiment, the one or more polymer compound (B) is obtainable by polymerizing a monomer composition comprising:

i) as component a) 3 to 40 % by weight, preferably 10 to 30 % by weight of 3- (Methacryloyloxy)propyl trimethoxysilane, based on the total weight of the monomer composition for preparing the polymer compound (B); and

ii) as component b) 60 to 97 % by weight, preferably 70 to 90 % by weight of Lauryl (meth)acrylate, based on the total weight of the monomer composition for preparing the polymer compound (B);

According to another preferred embodiment, the one or more polymer compound (B) is obtainable by polymerizing a monomer composition comprising

i) as component a) 1 to 15 % by weight, preferably 2 to 10 % by weight of 3- (Methacryloyloxy)propyl trimethoxysilane, based on the total weight of the monomer composition for preparing the polymer compound (B); and

ii) as component b1 ) 30 to 60 % by weight, preferably 40 to 60 % by weight of a mixture consisting of methyl (meth)acrylate and n-butyl (meth)acrylate monomers of formula (II), based on the monomer composition for preparing the polymer compound (B); and iii) as component b2) 10 to 20 % by weight, preferably 2 to 10 % by weight of Lauryl (meth)acrylate monomer of formula (III), based on the monomer composition for preparing the polymer compound (B); and

iv) as component c) 10 to 50 % by weight, preferably 20 to 40 % by weight of a mixture consisting of two macromonomers, the first macromonomer being prepared with a macroalcohol having a number-average molecular weight of 1 ,500 to 2,100 g/mol, more preferably 1 ,800 to 2,100 g/mol, most preferably 1 ,900 to 2, 100 g/mol, and the second macromonomer being prepared with a macroalcohol having a number-average molecular weight of 3,500 to 7,000 g/mol, preferably 4,000 to 6,000 g/mol, more preferably 4,500 to 5,000 g/mol, based on the monomer composition for preparing the polymer compound (B); preferably being the weight proportion of the lower molecular weight macromonomer to the higher molecular weight macromonomer 1 or more, more preferably 1.5 to 15, even more preferably 2 to 7, most preferably 3 to 6; and

v) as component d) 2 to 50 % by weight, preferably 10 to 25 % by weight of styrene, based on the monomer composition for preparing the polymer compound (B);

Preparation of the polymer (B)

According to the present invention, the above-mentioned polymers may be prepared following the method comprising the steps of:

(a) providing a monomer composition as describe above; and

(b) initiating radical polymerization in the monomer composition.

Standard free-radical polymerization is detailed, inter alia, in Ullmann's Encyclopedia of Industrial Chemistry, Sixth Edition. In general, a polymerization initiator and optionally a chain transfer agent are used for this purpose.

The polymerization can be conducted under standard pressure, reduced pressure or elevated pressure. The polymerization temperature is also uncritical. In general, however, it is in the range from -20 to 200°C, preferably 50 to 150°C and more preferably 80 to 130°C.

The polymerization step (b) may be performed with or without dilution in oil. If dilution is performed, then the amount of the monomer composition, i.e. the total amount of monomers, relative to the total weight of the reaction mixture is preferably 20 to 90 % by weight, more preferably 40 to 80 % by weight, most preferably 50 to 70 % by weight.

Preferably, the oil used for diluting the monomer mixture is an API Group I, II, III, IV or V oil, or a mixture thereof. Preferably, a Group III oil or a mixture thereof is used to dilute the monomer mixture.

Preferably, step (b) comprises the addition of a radical initiator.

Suitable radical initiators are, for example, azo initiators, such as azobis-isobutyronitrile (AIBN), 2,2'- azobis(2-methylbutyronitrile) (AMBN) and 1 , 1-azobiscyclohexanecarbonitrile, and peroxy compounds such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl peroxide, tert- butyl per-2-ethylhexanoate, ketone peroxide, tert- butyl peroctoate, methyl isobutyl ketone peroxide, cyclohexanone peroxide, dibenzoyl peroxide, ieri-butyl peroxybenzoate, ieri-butyl peroxyisopropylcarbonate, 2,5-bis(2-ethylhexanoylperoxy)-2,5-dimethylhexane, ieri-butyl peroxy-2- ethylhexanoate, ieri-butyl peroxy-3,5,5-trimethylhexanoate, dicumyl peroxide, 1 , 1 -bis(ieri- butylperoxy)cyclohexane, 1 ,1-bis(ieri-butylperoxy)-3,3,5-trinnethylcyclohexane, cumyl hydroperoxide, ieri-butyl hydroperoxide and bis(4-ieri-butylcyclohexyl) peroxydicarbonate.

Preferably, the radical initiator is selected from the group consisting of 2,2'-azobis(2- methylbutyronitrile), 2,2-bis(tert-butylperoxy)butane, ferf-butylperoxy 2-ethyl hexanoate, 1 , 1-di -ieri- butylperoxy-3,3,5-trimethylcyclohexan, ieri-butyl peroxybenzoate and ieri-butylperoxy-3,5,5- trimethylhexanoat. Particularly preferred initiators are ferf-butylperoxy 2-ethylhexanoate and 2,2- bis(tert-butylperoxy)butane.

Preferably, the total amount of radical initiator relative to the total weight of the monomer mixture is 0.01 to 5 % by weight, more preferably 0.02 to 1 % by weight, most preferably 0.05 to 0.6 % by weight.

The total amount of radical initiator may be added in a single step or the radical initiator may be added in several steps over the course of the polymerization reaction. Preferably, the radical initiator is added in several steps. For example, a part of the radical initiator may be added to initiate radical polymerization and a second part of the radical initiator may be added 0.5 to 3.5 hours after the initial dosage.

Preferably, step (b) also comprises the addition of a chain transfer agent. Suitable chain transfer agents are especially oil-soluble mercaptans, for example n-dodecyl mercaptan or 2- mercaptoethanol, or else chain transfer agents from the class of the terpenes, for example terpinolene. Particularly preferred is the addition of n-dodecyl mercaptan.

It is also possible to divide the monomer composition into an initial part and a second part and to add a part of the radical initiator to the initial part only to start the polymerization reaction therein. Then, the second part of the radical initiator is added to the second part of the monomer composition which is then added over the course of 0.5 to 5 hours, preferably 1 .5 to 4 hours, more preferably 2 to 3.5 hours, to the polymerization reaction mixture. After addition of the second monomer mixture, a third part of the radical initiator may be added to the polymerization reaction as described above.

Preferably, the total reaction time of the radical polymerization is 2 to 10 hours, more preferably 3 to 9 hours.

After completion of the radical polymerization, the obtained polymer is preferably further diluted with the above-mentioned oil to the desired viscosity. Preferably, the polymer is diluted to a concentration of 5 to 60 % by weight polymer, more preferably 10 to 50 % by weight, most preferably 20 to 40 % by weight.

The polymeric-inorganic nanoparticle composition of the invention and preparation process thereof

According to the invention, the weight ratio of the one or more intercalation compound (A) to the one or more polymer compound (B) is 20: 1 to 1 :5 , preferably 10:1 to 1 :2, more preferably 5: 1 to 1 : 1 , most preferably 4: 1 to 2: 1.

Preferably, the polymeric-inorganic nanoparticle composition comprising the one or more intercalation compound (A) and the one or more polymer compound (B) may further comprise a solvent (C), preferably being the solvent a base oil, an organic solvent or a mixture thereof.

The solvent (C) can be a base oil, selected from the list consisting of an API Group I base oil, an API Group II base oil, an API Group III, an API Group IV base oil and an API Group V base oil or a combination thereof.

The solvent (C) can be an organic solvent selected from the list of alkanes, aromatic hydrocarbons, esters, ethers or a combination thereof.

It is preferred, that the mixture comprises 30 to 99.9 %, more preferably 50 to 99 %, most preferably 70 to 99 % by weight of solvent (C).

The present invention also relates to a method for manufacturing a polymeric-inorganic nanoparticle composition according to the present invention, the method comprising the steps of:

(a) providing one or more intercalation compound (A);

(b) providing one or more polymer compound (B);

(c) preferably, providing a solvent (C);

(d) combining at least the one or more intercalation compound (A) and the one or more polymer compound (B) to obtain a mixture, preferably combining at least the one or more intercalation compound (A), the one or more polymer compound (B) and the solvent (C) to obtain a mixture; and

(e) milling the mixture.

According to this invention, the milling step (e) is defined by a resulting change of particle size distribution of the polymeric-inorganic nanoparticle composition measured using dynamic light scattering technology (DLS). The milling technology according to the invention described in step (e) can be milling via high pressure homogenization, high shear mixing, ultrasonic sound, ball milling, ultrahigh-pressure technology (jet mill) or a combination thereof. Indeed, the particle size of the agglomerates is reduced using these milling technologies.

According to a preferred embodiment of the method for manufacturing the polymeric-inorganic nanoparticle composition, the mixture of one or more intercalation compound (A), the one or more polymer compound (B) and the solvent (C) is milled via a ball mill process.

According to a preferred embodiment of the method for manufacturing the polymeric-inorganic nanoparticle composition, the mixture of one or more intercalation compound (A), the one or more polymer compound (B) and the solvent (C) is milled via a ball mill process. Preferably, the ball mill process comprises introducing 0.1 to 10 kWh/kg, preferably 1 to 5 kWh/kg, more preferably 1 .5 to 3 kWh/kg energy into the mixture.

In another preferred embodiment of the method for manufacturing the polymeric-inorganic nanoparticle composition, the mixture of one or more intercalation compound (A), the one or more polymer compound (B) and the solvent (C) is milled using an ultrasound equipment having between 10 to 1000 W, preferably 50 to 800 W and more preferably 100 to 500 W power. Preferably, the composition is milled for 1 to 240 minutes, more preferably for 10 to 180 minutes and even more preferably for 30 to 150 minutes to achieve a stable polymeric-inorganic nanoparticle composition.

By using a ball mill, the onion-like particles (intercalation compound (A)) will break apart and the individual layers, sheets of layers or fragments will be dispersed by the dispersing agent resulting in a dispersion with improved stability (see Figure 3). The individual layers, sheets of layers or fragments show surprisingly impressive extreme pressure performance in comparison with dispersion technologies which keep the onion shape like in the literature provided (see Figure 2).

Use of the polymeric-inorganic nanoparticle composition according to the invention

The invention also relates to the use of the polymeric-inorganic nanoparticle composition as defined herein as an additive for a lubricant composition.

The polymeric-inorganic nanoparticle composition as defined herein and the lubricant compositions comprising the polymeric-inorganic nanoparticle composition according to the invention are favorably used for driving system lubricating oils (such as manual transmission fluids, differential gear oils, automatic transmission fluids and belt-continuously variable transmission fluids, axle fluid formulations, dual clutch transmission fluids, and dedicated hybrid transmission fluids), hydraulic oils (such as hydraulic oils for machinery, power steering oils, shock absorber oils), engine oils (for gasoline engines and for diesel engines) and industrial oil formulations (such as wind turbine).

In a preferred embodiment according to the invention the polymeric-inorganic nanoparticle composition improves the extreme pressure performance of moving metal parts of an engine, a gearbox or pump of an automobile, a wind turbine, or a hydraulic system.

Formulation

The invention also relates to a formulation comprising:

(i) a base oil; and

(ii) a polymeric-inorganic nanoparticle composition as defined above.

In a preferred embodiment of the invention the base oil is selected from the list consisting of an API Group I base oil, an API Group II base oil, an API Group III base oil, an API Group IV base oil, an API Group V base oil, or a mixture of one or more of these base oils.

The formulation may be an additive formulation comprising the polymeric-inorganic nanoparticle composition according to the invention and a base oil as diluent. The additive formulation may, for example, be added as an extreme pressure additive to lubricants. Typically, the additive formulation comprises a relatively high amount of polymeric-inorganic nanoparticle composition according the invention.

The formulation may also represent a lubricant formulation comprising the polymer-inorganic nanoparticle composition according to the invention, a base oil and optionally further additives as discussed below. The lubricant formulation may, for example, be used as a transmission fluid or an engine oil. Typically, the lubricant formulation comprises a lower amount of polymer-inorganic nanoparticle composition according to the invention as compared to the aforementioned additive formulation.

If the formulation is used as an additive formulation, the amount of base oil (component (i)) preferably is 40 to 95 % by weight, more preferably 70 to 90 % by weight and the amount of polymer-inorganic nanoparticle composition (component (ii)) preferably is 5 to 60 % by weight, more preferably 10 to 30 % by weight.

If the formulation is used as a lubricant formulation, the amount of base oil (component (i)) is preferably 50 to 99.99 % by weight, more preferably 65 to 99.99 % by weight, even more preferably 75 to 99.9 % by weight, and the amount of polymer-inorganic nanoparticle composition (component (ii)) preferably is 0.01 to 50 % by weight, more preferably 0.01 to 35 % by weight, even more preferably 0.1 to 25 % by weight.

Preferably, the amounts of (i) and (ii) add up to 100 % by weight.

The base oil to be used in the formulation preferably comprises an oil of lubricating viscosity. Such oils include natural and synthetic oils, oil derived from hydrocracking, hydrogenation, and hydrofinishing, unrefined, refined, re-refined oils or mixtures thereof.

The base oil may also be defined as specified by the American Petroleum Institute (API) (see April 2008 version of "Appendix E-API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils", section 1 .3 Sub-heading 1.3. "Base Stock Categories").

The API currently defines five groups of lubricant base stocks (API 1509, Annex E - API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils, September 201 1 ). Groups I, II and III are mineral oils which are classified by the amount of saturates and sulphur they contain and by their viscosity indices; Group IV are polyalphaolefins; and Group V are all others, including e.g. ester oils. The table below illustrates these API classifications.

Table 1 : API definition of lubricant base stocks

Further base oils which can be used in accordance with the present invention are Group ll-lll Fischer-Tropsch derived base oils.

Fischer-Tropsch derived base oils are known in the art. By the term "Fischer-Tropsch derived" is meant that a base oil is, or is derived from, a synthesis product of a Fischer-Tropsch process. A Fischer-Tropsch derived base oil may also be referred to as a GTL (Gas-To-Liquids) base oil. Suitable Fischer-Tropsch derived base oils that may be conveniently used as the base oil in the lubricating composition of the present invention are those as for example disclosed in EP 0 776 959, EP 0 668 342, WO 97/21788, WO 00/15736, WO 00/14188, WO 00/14187, WO 00/14183, WO 00/14179, WO 00/081 15, WO 99/41332, EP 1 029 029, WO 01/18156, WO 01/57166 and WO 2013/189951.

Especially for transmission oil formulations, base oils of API Group III and mixtures of different Group III oils are used. In a preferred embodiment, the base oil may also be a polyalphaolefin base oil or a mixture of a polyalphaolefin base oil with an API Group III base oil or a mixture of API Group III base oils.

The lubricant formulation according to the invention may also contain, as component (iii), further additives selected from the group consisting of dispersants, defoamers, detergents, antioxidants, pour point depressants, antiwear additives, extreme pressure additives, anticorrosion additives, yellow metal passivators, friction modifiers, dyes and mixtures thereof.

Appropriate dispersants include poly(isobutylene) derivatives, for example poly(isobutylene)succinimides (PIBSIs), including borated PIBSIs; and ethylene-propylene oligomers having N/O functionalities.

Dispersants (including borated dispersants) are preferably used in an amount of 0 to 5% by weight, based on the total amount of the lubricant composition.

Suitable defoamers are silicone oils, fluorosilicone oils, fluoroalkyl ethers, etc.

The defoaming agent is preferably used in an amount of 0.001 to 0.2% by weight, based on the total amount of the lubricant composition.

The preferred detergents include metal-containing compounds, for example phenoxides; salicylates; thiophosphonates, especially thiopyrophosphonates, thiophosphonates and phosphonates; sulfonates and carbonates. As metal, these compounds may contain especially calcium, magnesium and barium. These compounds may preferably be used in neutral or overbased form.

Detergents are preferably used in an amount of 0.2 to 8% by weight, preferably 0.2 to 1 % by weight, based on the total amount of the lubricant composition.

The suitable antioxidants include, for example, phenol-based antioxidants and amine-based antioxidants.

Phenol-based antioxidants include, for example, octadecyl-3-(3,5-di-tert-butyl-4- hydroxyphenyl)propionate; 4,4' -methylenebis(2,6-di-tert-butylphenol); 4,4' -bis(2,6-di-t- butylphenol); 4,4' -b is(2-methyl-6-t-butylphenol); 2,2' -methylenebis(4-ethyl-6-t-butylphenol); 2,2' - methylenebis( 4-methyl-6-t-butyl phenol); 4,4' -butyl idenebis(3-methyl-6-t-butylphenol); 4,4'- isopropylidenebis(2,6-di-t-butylphenol); 2,2'-methylenebis(4-methyl-6-nonylphenol); 2,2'- isobutylidenebis(4,6-dimethylphenol); 2,2'-methylenebis(4-methyl-6-cyclohexylphenol); 2,6-di-t- butyl-4-methylphenol; 2,6-di-t-butyl-4-ethyl-phenol; 2,4-dimethyl-6-t-butylphenol; 2,6-di-t-amyl-p- cresol; 2,6-di-t-butyi-4-(N,N'-dimethylanninomethylphenol); 4,4'thiobis(2-methyl-6-t-butylphenol); 4,4'-thiobis(3-methyl-6-t-butylphenol); 2,2'-thiobis(4-methyl-6-t-butylphenol); bis(3-methyl-4- hydroxy-5-t-butylbenzyl) sulfide; bis(3,5-di-t-butyl-4-hydroxybenzyl) sulfide; n-octyl-3-(4-hydroxy- 3,5-di-t-butylphenyl)propionate; n-octadecyl-3-(4-hydroxy-3,5-di-t-butylphenyl)propionate; 2,2'- thio[diethyl-bis-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], etc. Of those, especially preferred are bis-phenol-based antioxidants and ester group containing phenol-based antioxidants.

The amine-based antioxidants include, for example, monoalkyldiphenylamines such as monooctyldiphenylamine, monononyldiphenylamine, etc.; dialkyldiphenylamines such as 4,4' - dibutyldiphenylamine, 4,4'-dipentyldiphe nylamine, 4,4'- dihexyldiphenylamine, 4,4'- diheptyldiphenylamine, 4,4'-dioctyldiphenylamine, 4,4'-dinonyldiphenylamine, etc.; polyalkyldiphenylamines such as tetrabutyldiphenylamine, tetrahexyldiphenylamine, tetraoctyldiphenylamine, tetranonyldiphenylamine, etc.; naphthylamines, concretely alpha- naphthylamine, phenyl-alpha-naphthylamine and further alkyl-substituted phenyl-alpha- naphthylamines such as butylphenyl-alpha-naphthylamine, pentylphenyl-alpha-naphthylamine, hexylphenyl-alpha-naphthylamine, heptylphenyl-alpha-naphthylamine, octylphenyl-alpha- naphthylamine, nonylphenyl-alpha-naphthylamine, etc. Of those, diphenylamines are preferred to naphthylamines, from the viewpoint of the antioxidation effect thereof.

Suitable antioxidants may further be selected from the group consisting of compounds containing sulfur and phosphorus, for example metal dithiophosphates, for example zinc dithiophosphates (ZnDTPs), "OOS triesters" = reaction products of dithiophosphoric acid with activated double bonds from olefins, cyclopentad iene, norbornadiene, a-pinene, polybutene, acrylic esters, maleic esters (ashless on combustion); organosulfur compounds, for example dialkyl sulfides, diaryl sulfides, polysulfides, modified thiols, thiophene derivatives, xanthates, thioglycols, thioaldehydes, sulfur- containing carboxylic acids; heterocyclic sulfur/nitrogen compounds, especially dialkyldimercaptothiadiazoles, 2-mercaptobenzimidazoles; zinc bis(dialkyldithiocarbamate) and methylene bis(dialkyldithiocarbamate); organophosphorus compounds, for example triaryl and trialkyl phosphites; organocopper compounds and overbased calcium- and magnesium-based phenoxides and salicylates.

Antioxidants are used in an amount of 0 to 15% by weight, preferably 0.01 to 10% by weight, more preferably 0.01 to 5% by weight, based on the total amount of the lubricant composition. Suitable anticorrosion additives are succinic acid partial esters, succinic acid partial ester amine salts, organic carboxylic acids, sulfonates and suitable yellow metal passivators are thiadiazoles, triazoles and high molecular phenolic antioxidants.

Anticorrosion additives are used in an amount of 0 to 5% by weight, yellow metal passivators are used in an amount of 0 to 1 % by weight, all amounts based on the total weight of the lubricant composition.

The pour-point depressants include ethylene-vinyl acetate copolymers, chlorinated paraffin- naphthalene condensates, chlorinated paraffin-phenol condensates, polymethacrylates, polyalkylstyrenes, etc. Preferred are polymethacrylates having a weight-average molecular weight of from 5,000 to 200,000 g/mol.

The amount of the pour point depressant is preferably from 0.1 to 5% by weight, based on the total amount of the lubricant composition.

The preferred antiwear and extreme pressure additives include sulfur-containing compounds such as zinc dithiophosphate, zinc di-C3-i₂-alkyldithiophosphates (ZnDTPs), zinc phosphate, zinc dithiocarbamate, molybdenum dithiocarbamate, molybdenum dithiophosphate, alkyl dithiophosphates, disulfides, sulfurized olefins, sulfurized oils and fats, sulfurized esters, thiocarbonates, thiocarbamates, polysulfides, etc.; phosphorus-containing compounds such as phosphites, phosphates, for example trialkyl phosphates, triaryl phosphates, e.g. tricresyl phosphate, amine-neutralized mono- and dialkyl phosphates, ethoxylated mono- and dialkyl phosphates, phosphonates, phosphines, amine salts or metal salts of those compounds, etc.; sulfur and phosphorus-containing anti-wear agents such as thiophosphites, thiophosphates, thiophosphonates, amine salts or metal salts of those compounds, etc.

The antiwear agent may be present in an amount of 0 to 3% by weight, preferably 0.1 to 1.5% by weight, more preferably 0.5 to 0.9% by weight, based on the total amount of the lubricant composition.

The preferred friction modifiers may include mechanically active compounds, for example molybdenum disulphide, graphite (including fluorinated graphite), poly (trifluorethylene), polyamide, polyimide; compounds which form adsorption layers, for example long-chain carboxylic acids, fatty acid esters, ethers, alcohols, amines, amides, imides; phosphonates, phosphites, compounds which from layers through tribochemical reactions, for example saturated fatty acids, phosphoric acid, boric acid esters and thiophosphoric esters, xanthogenates, sulphurized fatty acids; compounds which form polymer-like layers, for example ethoxylated dicarboxylic acid partial esters, dialkyl phthalates, methacrylates, unsaturated fatty acids, sulphurized olefins and organometallic compounds, for example molybdenum compounds (molybdenum dithiophosphates and molybdenum dithiocarbamates MoDTC) and their combinations with ZnDTPs, copper-containing organic compounds.

Some of the compounds listed above may fulfil multiple functions. ZnDTP, for example, is primarily an antiwear additive and extreme pressure additive, but also has the character of an antioxidant and corrosion inhibitor (here: metal passivator/deactivator).

The above-detailed additives are described in detail, inter alia, in T. Mang, W. Dresel (eds.): "Lubricants and Lubrication", Wiley-VCH, Weinheim 2001 ; R. M. Mortier, S. T. Orszulik (eds.): "Chemistry and Technology of Lubricants".

Preferably, the total concentration of the one or more additives (iii) is up to 20% by weight, more preferably 0.05% to 15% by weight, more preferably 5% to 15% by weight, based on the total weight of the lubricant formulation.

Preferably, the amounts of (i) to (iii) add up to 100 % by weight.

The all-in-once lubricant formulation comprising the polymeric-inorganic nanoparticle composition of the invention combines stability over the time, as well as improved anti-weld performance as shown below in the experimental part. This approach therefore avoids any incompatibilities between different package components, dispersing agents, and other additives in the lubricant formulation as a single additive combines all properties.

EXPERIMENTAL PART

The invention is further illustrated in detail hereinafter with reference to examples and comparative examples, without any intention to limit the scope of the present invention.

Abbreviations

Ci AMA Ci-alkyl methacrylate (methyl methacrylate; MMA)

C₄ AMA C₄-alkyl methacrylate (n-butyl methacrylate)

C12-14 AMA Ci₂-i₄-alkyl methacrylate

C16-18 AMA Ci6-i8-alkyl methacrylate

CTA Chain transfer agent

MEMO 3-(Methacryloyloxy)propyl trimethoxysilane

OCTMO Octyltrimethoxysilane

f branch degree of branching in mol%

MA-1 macroalcohol (hydroxylated hydrogenated polybutadiene M_n = 2,000 g/mol)

MA-2 macroalcohol (hydroxylated hydrogenated polybutadiene M_n = 4,750 g/mol)

MM-1 macromonomer of MA-1 with methacrylate functionality

MM-2 macromonomer of MA-2 with methacrylate functionality

Mn number-average molecular weight

Mw weight-average molecular weight

NB3020 Nexbase^® 3020, Group III base oil from Neste with a KV100 of 2.2 cSt

NB3043 Nexbase^® 3043, Group III base oil from Neste with a KV100 of 4.3 cSt

NB3060 Nexbase^® 3060, Group III base oil from Neste with a KV100 of 6.0 cSt

VISCOBASE 5-220 VISCOBASE^® 5-220 is a group V synthetic base fluid from Evonik with a

KV-ioo of 480 cSt

VISCOPLEX 14-520 defoamer

PPD pour point depressant

Dl package Afton HiTec^® 307 (detergent inhibitor)

PDI polydispersity index, molecular weight distribution calculated via M_w/M_n

Synthesis of a hydroxylated hydrogenated polvbutadiene (macroalcohoD MA-1 or MA-2

The macroalcohol was synthesized by anionic polymerization of 1 ,3-butadiene with butyllithium at 20-45 °C. On attainment of the desired degree of polymerization, the reaction was stopped by adding propylene oxide and lithium was removed by precipitation with methanol. Subsequently, the polymer was hydrogenated under a hydrogen atmosphere in the presence of a noble metal catalyst at up to 140 °C and 200 bar pressure. After the hydrogenation had ended, the noble metal catalyst was removed and organic solvent was drawn off under reduced pressure to obtain a 100% macroalcohol MA-1 or MA-2. Finally, MA-2 was diluted with NB3020 to a macroalcohol content of 70 % by weight, while MA-1 was kept 100 % (no dilution).

Table 2 summarizes the characterization data of MA-1 and MA-2.

Table 2: Characterization data of used macroalcohols.

Synthesis of macromonomers MM-1 or MM-2

In a 2 L stirred apparatus equipped with saber stirrer, air inlet tube, thermocouple with controller, heating mantle, column having a random packing of 3 mm wire spirals, vapor divider, top thermometer, reflux condenser and substrate cooler, 1000 g of the above-described macroalcohol are dissolved in methyl methacrylate (MMA) by stirring at 60 °C. Added to the solution are 20 ppm of 2,2,6,6-tetramethylpiperidin-1-oxyl radical and 200 ppm of hydroquinone monomethyl ether. After heating to MMA reflux (bottom temperature about 1 10 °C) while passing air through for stabilization, about 20 ml_ of MMA are distilled off for azeotropic drying. After cooling to 95 °C, UOCH3 is added and the mixture is heated back to reflux. After the reaction time of about 1 hour, the top temperature has fallen to ~64 °C because of methanol formation. The methanol/MMA azeotrope formed is distilled off constantly until a constant top temperature of about 100 °C is established again. At this temperature, the mixture is left to react for a further hour. For further workup, the bulk of MMA is drawn off under reduced pressure. Insoluble catalyst residues are removed by pressure filtration (Seitz T1000 depth filter).

Table 3 summarizes the MMA and LiOCF amounts used for the synthesis of macromonomers MM-1 and MM-2.

Table 3: Macroalcohols, MMA and catalyst amounts for the transesterification of the

macromonomers.

Synthesis of silane-containing polymers (B)

As already indicated above, the polymer weight average molecular weights were measured by gel permeation chromatography (GPC) calibrated using poly(methyl-methacrylate) standards. Tetrahydrofuran (THF) is used as eluent.

Example Polymer 1 (P1 V Preparation of a silane-containing copolymer according to the invention 300 grams of 3-(Methacryloyloxy)propyl trimethoxysilane (MEMO), 700 grams of lauryl methacrylate (C12-14 AMA), and 39 grams of n-dodecyl mercaptan (n-DDM) were charged into 2 liter, 4-necked round bottom flask. The reaction mixture was stirred using a C-stirring rod, inerted with nitrogen, and heated to 1 10°C. Once the reaction mixture reached the setpoint temperature, t-butylperoctoate was fed into the reactor over 3 hours. 0.13 grams of t-butylperoctoate were fed in the first hour, 0.63 grams of t-butylperoctoate were fed in the second hour and 1.75 grams started of t-butylperoctoate were fed in the third hour. After the final initiator feed, the reaction was held at 1 10°C for one hour. Residual monomer was measured by gas chromatography to ensure good monomer conversion. The polymer obtained has a weight-average molecular weight M_w of 10,500 g/mol (PMMA standard).

Example Polymer 2 (P2): Preparation of a silane-containing copolymer according to the invention An apparatus with 4-neck flask and precision glass saber is charged with the monomer composition whose composition is shown in Table 4 and the polymerization oil NB3020 is added, so that the concentration of monomers in oil is 37.5 wt%. After heating to 1 15 °C under nitrogen, a 10 wt% solution of tert-butylperoxy-2-ethylhexanoate and dodecyl mercaptan in NB3020 is added within three hours with constant dosing rate. The reaction mixture is stirred at 1 15 °C for additional 2 hours to obtain the final polymer. The M_w of the final polymer is 492,000 g/mol (PMMA standard).

Example Polymer 3 (P3): Preparation of a silane-containing copolymer according to the invention An apparatus with 4-neck flask and precision glass saber is charged with the monomer composition whose composition is shown in Table 4 and the polymerization oil NB3020 is added, so that the concentration of monomers in oil is 30 wt%. After heating to 1 15 °C under nitrogen, a 10 wt% solution of tert-butylperoxy-2-ethylhexanoate and dodecyl mercaptan in NB3020 is added within three hours with constant dosing rate. The reaction is maintained at 1 15 °C and 0.5 and 3.5 hours after the end of the initiator dosing, 0.2% (relative to the total amount of monomers) of 2,2-bis(tert- butylperoxy)butane are added. The reaction mixture is stirred at 1 15 °C for additional 2 hours to obtain the final polymer. The M_w of the final polymer is 770,000 g/mol (PMMA standard).

For the examples P1 , P2 and P3, the monomer components add up to 100%. The amount of initiator and chain transfer agent is given relative to the total amount of monomers. Table 4 below shows the monomer composition and reactants to prepare the polymers P1 , P2 and P3, as well as their final characterization.

Preparation of polymeric-inorganic nanoparticle concentrates according to the invention

Dispersion IE1 :

4 g of IF-WS2 particles are given into a solution of 14.8 g NB3043 oil including 1.2 g of P1 while this mixture is milled with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti- sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 100 nm.

Dispersion IE2 (with Ball Mill):

The ball mill equipment (Netzsch Laboratory Mill Micro Series) is pre-loaded with 259 g NB3043 oil and 21 g of P1 while the peristaltic pump is set to 80 rpm and the ball mill to 1000 rpm. Afterwards, 70 g of IF-WS2 particles are given into this solution. The ball mill is set to a rotation speed of 3500 rpm and the dispersion is treated until 1.0 kWh energy is introduced (240 minutes). The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 68 nm.

Dispersion IE3:

4 g of IF-WS2 particles are given into a solution of 12.8 g NB3043 oil including 3.2 g of P2 while this mixture is milled with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti- sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 134 nm.

Dispersion IE4:

4 g of IF-WS2 particles are given into a solution of 12 g NB3043 oil including 4 g of P3 while this mixture is treated with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti- sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 125 nm.

Preparation of polymeric-inorganic nanoparticle concentrates as comparative example

Dispersion CE1 :

4 g of IF-WS2 particles are given into a solution of 14.8 g NB3043 oil including 1.2 g of OCTMO while this mixture is treated with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti-sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 432 nm. Dispersion CE2:

4 g of IF-WS2 particles are given into a solution of 14.8 g NB3043 oil including 1.2 g of e-Caprolactam while this mixture is treated with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti-sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 1427 nm.

Dispersion CE3:

4 g of IF-WS2 particles are given into a solution of 14 g NB3043 oil including 2 g of OCTMO while this mixture is treated with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti- sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 618 nm.

Dispersion CE4:

4 g of IF-WS2 particles are given into a solution of 14 g NB3043 oil including 2 g of e-Caprolactam while this mixture is treated with ultrasound (ultrasound processor UP400S with 400 Watt, 24kHz with Ti-sonotrode) for 120 minutes, respectively. The particle size distribution (measured in Tegosoft DEC oil using dynamic light scattering equipment, LA- 950, Horiba Ltd., Japan) shows a d50 value of 1400 nm.

The table 5 below summarizes the compositions of the inventive dispersions (IE) according to the invention and the comparative dispersions (CE). The listed weight percentages are based on the total weight of the different compositions.

Table 5: Comparison of dispersions according the present invention

Dynamic light scattering (DLS)

The particle size distribution was measured in Tegosoft oil using the dynamic light scattering equipment LB-500 produced by Horiba Ltd.

Dynamic light scattering (DLS) is a technique in physics that can be used to determine the size distribution profile of small particles in suspension or polymers in solution. This equipment can be used to measure the particle size of dispersed material (inorganic nanoparticles or polymeric spheres, e.g.) in the range from 3 nm to 6 pm. The measurement is based on the Brownian motion of the particles within the medium and the scattering of incident laser light because of a difference in refraction index of liquid and solid material.

The resulting value is the hydrodynamic diameter of the particle’s corresponding sphere. The values d50, d90 and d99 are common standards for discussion, as these describe the hydrodynamic diameter of the particle below which 50%, 90% or 99% of the particles are within the particle size distribution. The lower these values, the better the particle dispersion. Monitoring these values can give a clue about the particle dispersion stability. If the values increase tremendously, the particles are not stabilized enough and may tend to agglomerate and sediment over time resulting in a lack of stability. Depending on the viscosity of the medium, it can be stated, that a d99 value of < 500 nm (e.g. for Nexbase base oil) is an indication for a stable dispersion as the particles are held in abeyance over time.

Determination of weld properties of the lubricating composition according to the invention

Lubricating formulations were prepared according to weight ratios shown in Table 6 below and their weld performances were tested using the method described below. The listed weight percentages are based on the total weight of the different formulations.

For the sake of comparison lubricating formulations are always compared based on the same content of intercalation compound. Therefore, formulations named with “-1” correspond to formulations having an intercalation compound concentration of 0.1 wt%, based on the total weight of lubricating formulation. Similarly“-2” corresponds to a concentration of 1 wt%.

Fully formulated oil composition according ISO VG 68:

79.25 wt% NB3060 (Base oil)

17.4 wt% VISCOBASE^® 5-220(Base oil)

0.7 wt% PPD

2.65 wt% Afton HiTec^® 307 (Dl package)

+ 0.2 wt% VISCOPLEX 14-520 (defoamer)

Determination of the improvement in weld (extreme pressure) according to four ball weld test

Four ball weld tests were performed according to DIN 51350 part 2 (results see figure 1 ). Table 7 summarizes the results of these 4 ball weld tests.

The reference base oil mixture (fully formulated oil ISO VG 68) welds at an average weld load of 5000 N.

Comparative Example Formulation CE1-1 represents a formulation of fully formulated oil ISO VG 68 with addition of 0.5 wt% of dispersion CE1 (corresponding to 0.1 wt% intercalation compound). Weld load was found to be 4500 N.

Comparative Example Formulation CE1-2 represents a formulation of fully formulated oil ISO VG 68 with addition of 5 wt% of dispersion CE1 (corresponding to 1 wt% intercalation compound). Weld load was found to be 4900 N.

Comparative Example Formulation CE2-1 represents a formulation of fully formulated oil ISO VG 68 with addition of 0.5 wt% of dispersion CE2 (corresponding to 0.1 wt% intercalation compound). Weld load was found to be 4200 N.

Comparative Example Formulation CE2-2 represents a formulation of fully formulated oil ISO VG 68 with addition of 5 wt% of dispersion CE2 (corresponding to 1 wt% intercalation compound). Weld load was found to be 3800 N.

Comparative Example Formulation CE3-1 represents a formulation of fully formulated oil ISO VG 68 with addition of 0.5 wt% of dispersion CE3 (corresponding to 0.1 wt% intercalation compound). Weld load was found to be 4300 N.

Comparative Example Formulation CE3-2 represents a formulation of fully formulated oil ISO VG 68 with addition of 5 wt% of dispersion CE3 (corresponding to 1 wt% intercalation compound). Weld load was found to be 4900 N.

Comparative Example Formulation CE4-1 represents a formulation of fully formulated oil ISO VG 68 with addition of 0.5 wt% of dispersion CE4 (corresponding to 0.1 wt% intercalation compound). Weld load was found to be 3900 N.

Comparative Example Formulation CE4-2 represents a formulation of fully formulated oil ISO VG 68 with addition of 5 wt% of dispersion CE4 (corresponding to 1 wt% intercalation compound). Weld load was found to be 4000 N. Inventive Examples contain the polymeric inorganic nanoparticles synthesized using Polymer P1 and IF-WS2. The particles are well dispersed and stable in the formulation. Inventive Example Formulation IE1-1 represents a formulation of fully formulated oil ISO VG 68 with addition of 0.5 wt% of dispersion IE1 (corresponding to 0.1 wt% intercalation compound). Weld load was found to be 7250 N. The measured weld load is increased by 45% compared to the fully formulated oil ISO VG 68 reference.

Inventive Example Formulation IE1-2 represents a formulation of fully formulated oil ISO VG 68 with addition of 5 wt% of dispersion IE1 (corresponding to 1 wt% intercalation compound). Weld load was found to be 7750 N. The measured weld load is increased by 55% compared to the fully formulated oil ISO VG 68 reference.

Inventive Examples IE2 contain the polymeric inorganic nanoparticles synthesized using Polymer P1 and IF-WS2. The particles are well dispersed with ball mill technology and stable in the formulation.

Inventive Example Formulation IE2-1 represents a formulation of fully formulated oil ISO VG 68 with addition of 0.5 wt% of dispersion IE1 (corresponding to 0.1 wt% intercalation compound). Weld load was found to be 8000 N. The measured weld load is increased by 60% compared to the fully formulated oil ISO VG 68 reference.

Table 7: Results of the weld tests

The higher the weld load, the better the extreme pressure performance. The reference oil formulation reaches a weld load of 5000 N. We can see the clear proof that the addition of polymeric- inorganic nanoparticle composition according to the present invention into a lubricating oil formulation improves the weld performance of the lubricating oil drastically. In comparison, the state- of-art dispersions (CE1-CE4) have lower weld load values, even lower than the reference oil formulation without any particles. The above experimental results show that the polymeric-inorganic nanoparticle compositions of the invention results in stable intercalation compound containing lubricating oil compositions, while maintaining or even improving the weld performance of the treated lubricating oil compositions. This result is surprising because the stability of lubricating oils with nanoparticles is limited over time as shown by the comparative examples with lower weld load values as the non-treated reference oil composition.

Determination of shear stability for the inventive dispersion IE2

Shear stability test was performed according to DIN 51350 (Part 6).

Inventive Example IE2 contains the polymeric-inorganic nanoparticle composition synthesized using Polymer P1 and IF-WS2. The particles are well dispersed and stable in the formulation.

Inventive Example Formulation IE2 with 0.25 wt% intercalation compound content represents a formulation of fully formulated oil ISO VG 68 with addition of 1.25 wt% of dispersion IE2. This formulation according to the invention is still stable after shear test.

Claims

1. A polymeric-inorganic nanoparticle composition, obtainable by milling a mixture, the mixture comprising one or more intercalation compound (A) and one or more polymer compound (B),

(B) wherein the one or more polymer compound is obtainable by polymerizing a monomer composition comprising:

a) one or more compounds of formula (I)

wherein R = H or CH₃

where 0 < h < 2

Si(A)h(X)3-h is a silane functional group,

A is a branched or unbranched C1 to C4 alkyl residue,

X is selected from H, Cl or a group OY , wherein Y is H or a C1 to C30 branched or unbranched alkyl-, alkenyl-, aryl-, or aralkyl- group, branched or unbranched C2 to C30 alkylether-group or branched or unbranched C2 to C30 alkylpolyether-group or a mixture thereof, and b) one or more alkyl (meth)acrylates, and wherein the weight ratio of the one or more intercalation compound (A) to the one or more polymer compound (B) is 20: 1 to 1 :5.

2. The polymeric-inorganic nanoparticle composition according to claim 1 , wherein the one or more alkyl (meth)acrylates b) has an alkyl group comprising from 1 to 40 carbon atoms.

3. The polymeric-inorganic nanoparticle composition according to claim 1 or 2, wherein the monomer composition further comprises one or more components c) prepared by the reaction of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene having a number-average molecular weight (M_n) of 500 to 10,000 g/mol.

4. The polymeric-inorganic nanoparticle composition according to any one of any one of claims 1 to 3, wherein each of the one or more alkyl (meth)acrylate monomers b) independently is b1 ) of formula (II):

wherein R is hydrogen or methyl, R³ means a linear, branched or cyclic alkyl residue with 16 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 16 to 20 carbon atoms.

5. The polymeric-inorganic nanoparticle composition according to any one of claims 1 to 4, wherein the weight ratio of the one or more intercalation compound (A) to the one or more polymer compound (B) is 10: 1 to 1 :2, more preferably 5:1 to 1 : 1 , most preferably 4: 1 to 2: 1.

6. The polymeric-inorganic nanoparticle composition according to any one of claims 1 , 2, 4 and 5, wherein the one or more polymer compound (B) is obtainable by polymerizing a monomer composition comprising:

a) 1 to 60 % by weight, preferably 3 to 40 % by weight, most preferably 10 to 30 % by weight, of the one or more compounds of formula (I), based on the total weight of the monomer composition for preparing the polymer compound (B); and b) 40 to 99 % by weight, preferably 60 to 97 % by weight, most preferably 70 to 90 % by weight, of the one or more alkyl (meth)acrylate monomer b), based on the monomer composition for preparing the polymer compound (B);

7. The polymeric-inorganic nanoparticle composition according to any one of claims 3 to 5, wherein the one or more polymer compound (B) is obtainable by polymerizing a monomer composition comprising:

b) 20 to 60 % by weight of one or more C-i-8 alkyl (meth)acrylates (b1 ) and 1 to 40 % by weight of one or more C9-15 alkyl (meth)acrylates (b2), preferably 30 to 60 % by weight of one or more C1-8 alkyl (meth)acrylates (b1 ) and 1 to 20 % by weight of one or more C9-15 alkyl (meth)acrylates (b2), more preferably 40 to 60 % by weight of one or more C1-8 alkyl (meth)acrylates (b1 ) and 2 to 10 % by weight of one or more C9-15 alkyl (meth)acrylates (b2), based on the total weight of the monomer composition,

c) 5 to 60 % by weight, preferably 10 to 50 % by weight, more preferably 20 to 40 % by weight, of one or more components c), prepared by the reaction of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene, based on the total weight of the monomer composition, and

8. The polymeric-inorganic nanoparticle composition according to claim 7, wherein the additional monomers d) include styrene monomers having from 8 to 17 carbon atoms and optionally dispersing oxygen- and/or nitrogen-functionalized monomers.

9. A method for manufacturing a polymeric-inorganic nanoparticle composition as defined in any one of claims 1 to 8, the method comprising the steps of:

(a) providing one or more intercalation compound (A);

(b) providing one or more polymer compound (B);

(c) preferably, providing a solvent (C), preferably being the solvent a base oil, an organic solvent or a mixture thereof

(e) milling the mixture.

10. The method according to claim 9, wherein at least the one or more intercalation compound (A), the one or more polymer compound (B) and the solvent (C) are combined to obtain the mixture, and wherein the step (e) comprises milling the mixture via a ball mill process, preferably introducing 0.1 to 10 kWh/kg, more preferably 1 to 5 kWh/kg, most preferably 1.5 to 3 kWh/kg energy into the mixture.

1 1. Use of the polymeric-inorganic nanoparticle composition according to any one of claims 1 to 8 as an additive for a lubricant composition.

12. A formulation comprising:

(a) a base oil; and

(b) a polymeric-inorganic nanoparticle composition according to any one of claims 1 to 8.

13. The formulation according to claim 12, wherein the base oil is selected from the list consisting of an API Group I base oil, an API Group II base oil, an API Group III base oil, an API Group IV base oil, an API Group V base oil, or a mixture of one or more of these base oils.

14. The formulation according to claim 12 or 13, comprising (i) 40 to 95 % by weight, more preferably 70 to 90 % by weight of base oil and (ii) 5 to 60 % by weight, more preferably 10 to 30 % by weight of the polymeric-inorganic nanoparticle composition, based on the total weight of the formulation.

15. The formulation according to claim 12 or 13, comprising (i) 50 to 99.99 % by weight, more preferably 65 to 99.99 % by weight, even more preferably 75 to 99.9 % by weight of base oil and (ii) 0.01 to 50 % by weight, more preferably 0.01 to 35 % by weight, even more preferably 0.1 to 25 % by weight of the polymeric-inorganic nanoparticle composition, based on the total weight of the formulation.