CN120936697A

CN120936697A - Lubricant additive composition for electric vehicles

Info

Publication number: CN120936697A
Application number: CN202480021675.6A
Authority: CN
Inventors: M·P·加哈根; S·杰弗里斯
Original assignee: Lubrizol Corp
Current assignee: Lubrizol Corp
Priority date: 2023-03-29
Filing date: 2024-03-28
Publication date: 2025-11-11
Also published as: WO2024206581A1

Abstract

The disclosed technology relates to lubricant additives containing dispersants, corrosion inhibitors, phosphorus antiwear agents, antioxidants, and sulfur-free detergents. The disclosed technology also relates to a lubricating composition containing a lubricant additive, wherein the lubricating composition is used for lubricating a transmission of an electric vehicle, and in particular for a gearbox.

Description

Lubricant additive composition for electric vehicles

Background

The disclosed technology relates to a lubricating composition for an electric vehicle drive train, especially for a gearbox of an electric vehicle, the lubricant additive composition comprising an oil of lubricating viscosity, a dispersant, a corrosion inhibitor, a phosphorus antiwear agent, an antioxidant and a sulfur-free detergent.

Electric and hybrid electric vehicles may include a power source (a conventional internal combustion engine such as a gasoline or diesel engine and/or a battery source coupled to an electric motor) in combination with a transmission for transmitting power to the wheels of the vehicle. The transmission may include an electric motor and/or a gear reduction unit coupled to the wheels. In some applications, a lubricant reservoir is provided that contains a lubricant composition for lubricating an electric motor and a power gear reduction unit.

In electric and hybrid electric vehicle applications, the lubrication fluid may come into contact with components of the electric motor as well as components of a conventional internal combustion engine gear reduction unit. Thus, a suitable fluid must be suitable for use with very different types of vehicle components. For example, the lubrication fluid may contact electrical windings in the motor stator and gears in the mechanical portion of the transmission. Thus, suitable fluids for these applications must not only have conventional lubricating properties, but also be compatible with electronic components.

In order to be suitable for use in electrical components, the fluid must provide good lubrication, electrical conductivity, and cooling properties at the same time. In general, such conventional fluids may not be suitable for use in electric or hybrid electric vehicles because one or more of the desired characteristics of the electric and hybrid electric applications are compromised by the accumulation of additives typically used in such conventional fluids.

However, the lubricant still must provide adequate lubrication, including, for example, dispersancy, cleanliness, wear resistance, and corrosion resistance. Also, it is desirable to maintain low viscosity fluids for such vehicles to improve vehicle efficiency. Thus, new lubricating compositions are needed to achieve these often competing results.

Disclosure of Invention

The disclosed technology provides a lubricant additive composition containing a dispersant, a corrosion inhibitor, a phosphorus antiwear agent, an antioxidant, and a sulfur-free detergent. The lubricant containing the lubricant additive composition may have a viscosity of 1cSt to 32cSt at 100 ℃, as measured by ASTM D445.

The lubricant additive composition may be mixed with a base oil such as an API group III base oil, a group IV base oil, or mixtures thereof to prepare a lubricating composition.

The lubricating composition containing the lubricant additive composition may be used in a method of lubricating an electric vehicle by supplying the lubricating composition to a driveline of the electric vehicle. In some cases, the method may be employed without the driveline including a shift clutch. In some cases, the lubricant additives provide improvements in dispersancy, cleanliness, wear resistance, oxidation performance (control), and corrosion resistance.

Detailed Description

Various preferred features and embodiments will be described below by way of non-limiting illustration.

One aspect of the present technology is a lubricant additive composition. The lubricant additive composition may be used in a lubricating composition with a base oil to provide lubrication in a drive train of an electric vehicle. The lubricant additive composition may include, inter alia, at least dispersants, corrosion inhibitors, antiwear additives, antioxidants, and sulfur-free detergents in sufficient amounts.

Dispersing agent

Dispersants may include, for example, "succinimide dispersants", which are carboxyl dispersants prepared by reacting a hydrocarbyl-substituted succinic anhydride or reactive equivalent thereof with an amine such as poly (ethyleneamine), "amine dispersants", which are reaction products of relatively high molecular weight aliphatic or cycloaliphatic halides and amines such as polyalkylene polyamines, "mannich dispersants", i.e., reaction products of alkylphenols wherein the alkyl group contains at least 30 carbon atoms with aldehydes, especially formaldehyde, and amines, especially polyalkylene polyamines, and "ester dispersants", which are similar to the succinimide dispersants described above, except that they may be considered to be prepared by reacting a hydrocarbyl acylating agent and an aliphatic polyol such as glycerol, pentaerythritol, or sorbitol, as described in U.S. Pat. No. 3,381,022.

Another class of ashless dispersants is high molecular weight esters. These materials are similar to the succinimides described above, except that they may be considered to be prepared by the reaction of a hydrocarbyl acylating agent and an aliphatic polyol such as glycerol, pentaerythritol or sorbitol. Such materials are described in more detail in U.S. Pat. No. 3,381,022. Aromatic succinates may also be prepared as described in U.S. patent publication 2010/0286414. In some cases, these ester dispersants may be post-treated with an amine, such as poly (ethyleneamine).

Post-treatment dispersants may also be used. Post-treated dispersants are typically obtained by reacting a carboxylic acid (e.g., succinimide), amine, or mannich dispersant with a reagent such as urea, thiourea, carbon disulfide, aldehyde, ketone, carboxylic acid, hydrocarbyl-substituted succinic anhydride, nitrile, epoxide, boron compound such as boric acid (to produce a "borated dispersant" as described above), phosphorus compound such as phosphoric acid or anhydride, 2, 5-dimercaptothiadiazole (DMTD), or an aromatic diacid having an acid group in the 1,3 or 1,4 position on the benzene ring such as terephthalic acid.

Borated dispersants are typically obtained by reacting a carboxylic acid (e.g., succinimide), amine, or mannich dispersant with a boron compound reagent such as boric acid (to produce a "borated dispersant"). Dispersants and methods for their production are well known in the art. The borated dispersant may additionally be partially functionalized with sulfur or phosphorus. The dispersant component of the borated dispersant may be a mixture of a plurality of dispersants, which may be of different types, optionally at least one of which may be a succinimide dispersant. In one embodiment, the borated dispersant may be a borated polyisobutylene succinimide dispersant, where the polyisobutylene portion thereof may have a number average molecular weight of 750 to 2200, or 750 to 1600, or 950 to 1550. The one or more borated dispersants may be prepared with an N to CO ratio of from 0.9:1 to 1.6:1, or from 0.95:1 to 1.5:1, or from 1:1 to 1.4:1. The amount of borated dispersant in the composition may be, for example, from 0.05 wt% to 2.0 wt%. In other embodiments, the amount is from 0.1% to 1.0%, or from 0.15% to 0.75% of the final blended fluid formulation. In the concentrate, this amount will become proportionally higher.

Mixtures of dispersants may also be used. The nitrogen content of the dispersant may be greater than or equal to about 11,000ppm, or greater than or equal to about 11,500ppm, or greater than or equal to about 12,000ppm, by weight of the dispersant.

The total amount of one or more dispersants, or combinations thereof, in the composition (whether post-treated (e.g., borated or non-borated)) can be, for example, 0.01 to 3 wt.%, or, for example, 0.025 to 2.75 wt.%, or 0.05 to 2.5 wt.%, or 1 to 2.5 wt.%, of the final blend fluid formulation, although the amount will be proportionately higher as a concentrate. To the extent that the dispersant is borated, the dispersant may provide less than 250ppm boron, or less than 200ppm boron, or even less than 150ppm boron, or less than 100ppm boron, or less than 90ppm boron, or even less than 80ppm boron to the composition, and in some cases less than 70ppm boron to the composition.

In certain embodiments, the dispersants may be prepared by a process involving the presence of small amounts of chlorine or other halogens, as described in U.S. patent 7,615,521 (see, e.g., column 4, line 18 to line 60 and preparation example a). Such dispersants typically have some carbocyclic ring structure in the linkage of the hydrocarbyl substituent to the acidic or amide "head" group. In other embodiments, dispersants may be prepared by thermal methods involving "ene" reactions without the use of any chlorine or other halogens, as described in U.S. patent 7,615,521, dispersants prepared in this way are typically derived from high vinylidene (i.e., greater than 50% terminal vinylidene) polyisobutenes (see column 4, line 61 to column 5, line 30 and preparation example B). Such dispersants typically do not contain the above-described carbocyclic ring structure at the point of attachment. In certain embodiments, the dispersant may be prepared by free-radical catalyzed polymerization of a high vinylidene polyisobutylene with an ethylenically unsaturated acylating agent, as described in U.S. patent 8,067,347.

The dispersant can also be a graft copolymer that is the condensation reaction product of an olefin polymer having grafted thereon carboxylic acid (or equivalent) functional groups, the grafted olefin being reacted with a monoamine or polyamine that may have a single primary amino group. If the olefin polymer is an ethylene/propylene copolymer, the polyamine is not a poly (vinylamine).

The polymeric substrate will be an olefin polymer such as those described above. The olefin polymer substrate employed in the derivatized graft copolymer will contain grafted carboxylic acid functionality or a reactive equivalent of carboxylic acid functionality (e.g., anhydride or ester). The reactive carboxylic acid functional groups will typically be present as pendant groups attached by, for example, a grafting process.

Ethylenically unsaturated carboxylic acid species are typically group grafted onto the polymer backbone. These substances attached to the polymer generally contain at least one olefinic bond (prior to the reaction) and at least one, such as two carboxylic acid (or anhydride thereof) groups or polar groups convertible to said carboxylic groups by oxidation or hydrolysis. Maleic anhydride or its derivatives are suitable. Which is grafted onto an olefin polymer (e.g., an ethylene copolymer or terpolymer) to provide two carboxylic acid functionalities. Examples of additional unsaturated carboxylic acid materials include maleic anhydride, itaconic anhydride (itaconic anhydride) or the corresponding dicarboxylic acids, such as maleic acid, fumaric acid and esters thereof, and cinnamic acid and esters thereof.

The ethylenically unsaturated carboxylic acid species may be group grafted onto a polymer, such as an ethylene/propylene copolymer. The radical-induced grafting of ethylenically unsaturated carboxylic acid species may also be carried out in a solvent such as hexane or mineral oil. It may be carried out at an elevated temperature in the range of 100 ℃ to 250 ℃, e.g. 120 ℃ to 190 ℃, or 150 ℃ to 180 ℃, e.g. above 160 ℃.

Free radical initiators that may be used include peroxides, hydroperoxides, and azo compounds, typically those having a boiling point greater than about 100 ℃ and which thermally decompose within the grafting temperature range to provide free radicals. Representative of these free radical initiators include azobisisobutyronitrile and 2, 5-dimethyl-hex-3-yne-2, 5-bis-t-butyl peroxide. The amount of initiator may be from 0.005 wt% to 1 wt% based on the weight of the reaction mixture solution. The grafting may be performed under an inert atmosphere, such as under a nitrogen blanket. The resulting polymer intermediate is characterized by carboxylic acid acylated functional groups within its structure.

In an alternative embodiment, an unsaturated carboxylic acid species (such as maleic anhydride) can be first condensed with a monoamine or polyamine, typically having a single primary amino group (as described below), and the condensation product itself subsequently grafted onto the polymer backbone in a similar manner as described above.

The amount of reactive carboxylic acid on the polymer chain, and in particular the amount of grafted carboxylic acid on the chain, is typically from 0.5 wt% to 8 wt%, or from 1 wt% to 7 wt%, or from 1.5 wt% to 6 wt%, or in some embodiments from 2 wt% to 5 wt%, based on the weight of the polymer backbone. In some embodiments, the amount of reactive carboxylic acid on the polymer chain, and in particular the amount of grafted carboxylic acid on the chain, can be from about 1 wt% to about 2 wt%, or in other embodiments from about 2 wt% to 3 wt%, or from about 3 wt% to 4 wt%, or from 4 wt% to 5 wt%. These numbers indicate the amount of carboxylic acid-containing species, in particular maleic anhydride as grafting material. As will be apparent to those skilled in the art, the amount may be adjusted to account for carboxylic acid-containing species having higher or lower molecular weights or higher or lower amounts of acid functionality per molecule. The grafting may be to a degree to provide an acid-functionalized polymer having a total acid number (TAN, according to ASTM D664) of from 5mgKOH/g to 100mgKOH/g, from 10mgKOH/g to 80mgKOH/g, or from 15mgKOH/g to 75mgKOH/g, or from 20mgKOH/g to 70mgKOH/g, or from about 20mgKOH/g to about 60mgKOH/g, or 65 mgKOH/g.

The acid-containing polymer is reacted with a monoamine or polyamine, typically having a single primary amino group. If the olefin polymer is an ethylene/propylene copolymer, the polyamine is not a poly (vinylamine). The reaction may consist of a condensation to form an imide, amide or semi-amide or amide ester (assuming a part of the alcohol is also reacted) or an amine salt. Primary amino groups will typically condense to form amides or, in the case of maleic anhydride, imides. It should be noted that in certain embodiments, the amine will have a single primary amino group, that is, it will have no two or more primary amino groups (e.g., less than 5% or 2% or 1% or 0.5%, or 0.01% to 0.1%, especially 1% or less, such as 0.01% to 1%, of the amine groups being primary amino groups, except for an insignificant amount of additional primary amino groups that may be in the entire amine component). This feature will minimize the amount of crosslinking that might otherwise occur. Poly (vinylamine) can be generally and in an oversimplified manner described as H ₂N-(C₂H₄-NH-)_n-C₂H₄-NH₂, where n can be, for example, 2 to 6. These typically have an average of about 2 primary amino groups and therefore their use for the functionalization of ethylene/propylene copolymers is generally undesirable, so that any undesired crosslinking can be minimized or avoided. In those embodiments where the polyamine is not a poly (vinylamine), the amine component used to prepare the condensation product will be free or substantially free of poly (vinylamine), such as less than 5 wt%, or less than 1 wt%, or from 0.01 wt% to 0.1 wt% of the amine component is poly (vinylamine).

Suitable primary amines can include aromatic amines, such as amines in which a carbon atom of an aromatic ring structure is directly attached to an amino nitrogen. The amine may be a monoamine or a polyamine. The aromatic rings will typically be mononuclear aromatic rings (i.e., rings derived from benzene), but may include fused aromatic rings, such as those derived from naphthalene. Examples of aromatic amines include aniline, N-alkylaniline (e.g., N-methylaniline) and N-butylaniline, di- (p-methylphenyl) amine, naphthylamine, 4-aminodiphenylamine, N-dimethylbenzenediamine, 4- (4-nitrophenylazo) aniline (disperse orange 3), sulfadimidine, 4-phenoxyaniline, 3-nitroaniline, 4-aminoacetoanilide, 4-amino-2-hydroxy-benzoic acid phenyl ester (phenylaminosalicylate), N- (4-amino-5-methoxy-2-methyl-phenyl) -benzamide (fast violet B), N- (4-amino-2, 5-dimethoxy-phenyl) -benzamide (fast blue RR), N- (4-amino-2, 5-diethoxy-phenyl) -benzamide (fast blue BB), N- (4-aminophenyl) -benzamide and 4-phenylazoaniline. Other examples include p-ethoxyaniline, p-dodecylaniline, cyclohexyl-substituted naphthylamines, and thienyl-substituted anilines. Examples of other suitable aromatic amines include amino-substituted aromatic compounds and amines in which the amine nitrogen is part of an aromatic ring, such as 3-aminoquinoline, 5-aminoquinoline, and 8-aminoquinoline. Also included are aromatic amines such as 2-aminobenzimidazole which contain one secondary amino group attached directly to the aromatic ring and a primary amino group attached to the imidazole ring. Other amines include N- (4-anilinophenyl) -3-aminobutanamide (i.e., phi-NH-COCH ₂CH(CH₃)NH₂). Additional aromatic amines include aminocarbazoles, aminoindoles, aminopyrroles, aminoindazolinones, amino-naphthyridines, mercaptotriazoles, amino-phenothiazines, aminopyridines, aminopyrazines, aminopyrimidines, pyridines, pyrazines, pyrimidines, aminothiothiadiazoles, and aminobenzotriazoles. Other suitable amines include 3-amino-N- (4-anilinophenyl) -N-isopropylbutyramide and N- (4-anilinophenyl-3- { (3-aminopropyl) - (cocoalkyl) amino } butyramide other aromatic amines that may be used include a variety of aromatic amine dye intermediates comprising a plurality of aromatic rings linked by, for example, an amide structure examples include those of the general structure phi-CONH-phi-NH ₂ wherein the phenyl group may be substituted.

The amine may also be non-aromatic, or in other words, an amine in which the amino nitrogen is not directly attached to a carbon atom of an aromatic ring, or an amine in which the amine nitrogen is not part of an aromatic ring, or an amine in which the amine nitrogen is not a substituent on an aromatic carboxylic acid compound. In some cases, such non-aromatic amines may be considered aliphatic or cycloaliphatic. Such amines may be linear, or branched, or functionalized with certain functional groups. Non-aromatic amines can include monoamines having, for example, 1 to 8 carbon atoms, such as methylamine, ethylamine, and propylamine, as well as various higher amines. Diamines or polyamines can also be used and will typically have only a single primary amino group. Examples include dimethylaminopropylamine, diethylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, dibutylaminoethylamine, 1- (2-aminoethyl) piperidine, 1- (2-aminoethyl) -pyrrolidone, N-dimethylethylamine, 3- (dimethylamino) -1-propylamine, O- (2-aminopropyl) -O' - (2-methoxyethyl) polypropylene glycol, N-dimethyldipropylenetriamine, aminoethylmorpholine, 3-morpholinoethyl propylamine, aminoethylethylene urea and aminopropylmorpholine.

In certain embodiments, the non-aromatic amines can be used alone or in combination with each other or with aromatic amines. In some embodiments, the amount of aromatic amine may be trace compared to the amount of non-aromatic amine, or in some cases, the composition may be substantially free or free of aromatic amine.

In certain embodiments, the grafted olefin polymer may have a nitrogen content of from 0.05 wt% to 3 wt%, or from 0.1 wt% to 2.5 wt%, or from 0.15 wt% to 2 wt%, or from 0.2 wt% to 1.75 wt%, or from 0.25 wt% to 1.6 wt%, calculated using ASTM D5291.

Corrosion inhibitors

Corrosion inhibitors may also be described as metal deactivators or yellow metal deactivators.

Examples of corrosion inhibitors include triazoles such as benzotriazole and 1,2, 4-triazole, benzimidazole, or mixtures thereof. In one embodiment, the corrosion inhibitor comprises benzotriazole. In another embodiment, the corrosion inhibitor comprises bis (2-ethylhexyl) - [1,2, 4-triazol-1-yl) methyl ] amine.

The triazole includes a triazole containing a hydrocarbyl substituent in at least one of the following ring positions 1-, 2-, 4-, 5-, 6-or 7-. The hydrocarbyl groups in various embodiments contain from 1 to about 30, or from 1 to about 15, or from 1 to about 16 carbon atoms. In one embodiment, the corrosion inhibitor comprises tolyltriazole. In one embodiment, the hydrocarbyl triazole substituted in position 4-or 5-or 6-or 7-is also reacted with an aldehyde and an amine.

Examples of suitable hydrocarbyl benzotriazoles that are also reacted with aldehydes and amines include N, N-bis (2-ethylhexyl) -aryl-methyl-1H-benzotriazol-1-methylamine, N-bis (2-ethylhexyl) -4-methyl-1H-benzotriazol-1-methylamine, 2H-benzotriazol-2-methylamine, N- (4-methoxyphenyl) -1H-benzotriazol-1-methylamine, N, N-didodecyl-1H-benzotriazole-1-methylamine, N- (1H-benzotriazole-1-ylmethyl) -N- (2-ethylhexyl) -1H-benzotriazole-1-methylamine, N-methyl-N-phenyl-1H-benzotriazole-1-methylamine, 4,5,6, 7-tetrahydro-N, N-ditridecyl-1H-benzotriazole-1-methylamine, N-dioctadecyl-1H-benzotriazole-1-methylamine, 5-methyl-N, N-dioctyl-1H-benzotriazole-1-methylamine, N-dibutyl-1H-benzotriazole-1-methylamine, N- (4-methylphenyl) -1H-benzotriazole-1-methylamine, N, N-bis (2-ethylhexyl) -1H-benzotriazole-1-methylamine, N, N-dioctyl-2H-benzotriazole-2-methylamine, N-dodecyl-1H-benzotriazole-1-methylamine, N-phenyl-1H-benzotriazole-1-methylamine, N, N-didodecyl-4, 5,6, 7-tetrahydro-1H-benzotriazole-1-methylamine, N, N-bis (2-ethylhexyl) -5-methyl-1H-benzotriazole-1-methylamine, N-octadecyl-1H-benzotriazole-1-methylamine, N, N-didodecyl-2H-benzotriazole-2-methylamine, N, N-dioctyl-1H-benzotriazole-1-methylamine, N- (2-ethylhexyl) -1H-benzotriazole-1-methylamine, 4,5,6, 7-tetrahydro-N, N-ditetradecyl-1H-benzotriazole-1-methylamine, or mixtures thereof. In one embodiment, the corrosion inhibitor comprises N, N-bis (2-ethylhexyl) -4-methyl-1H-benzotriazole-1-methylamine or N, N-bis (2-ethylhexyl) -aryl-methyl-1H-benzotriazole-1-methylamine.

Examples of suitable hydrocarbyl 1,2, 4-triazoles that are also reacted with amines include N, N-bis (1-methylethyl) -1H-1,2, 4-triazole-1-methylamine, N-diisobutyl-1H-1, 2, 4-triazole-1-methylamine, N-dicyclohexyl-1H-1, 2, 4-triazole-1-methylamine, N-bis (2-ethylhexyl) -1H-1,2, 4-triazole-1-methylamine, 1- ((1H-1, 2, 4-triazol-1-yl) methyl) piperidine, N, N-bis (tridecyl) -1H-1,2, 4-triazol-1-ylamine, N-dimethyl-1- (1H-1, 2, 4-triazol-1-yl) methylamine, N-dibutyl-1H-1, 2, 4-triazol-1-methylamine, N-dicoyl-1- (1H-1, 2, 4-triazol-1-yl) methylamine, N- ((1H-1, 2, 4-triazol-1-yl) methyl) oct-3-amine.

In various embodiments, the corrosion inhibitor is a triazole. Triazole corrosion inhibitors may be present alone or in mixtures with other triazole corrosion inhibitors or other azole corrosion inhibitors, ranging from about 0.005 wt.% or 0.01 wt.% to about 0.1 wt.%, or about 0.03 wt.% to about 0.08 wt.%, or about 0.04 wt.% to about 0.068 wt.%, or about 0.045 wt.% to about 0.057 wt.% of the lubricant additive composition.

Phosphorus antiwear compounds

The lubricant additive composition contains at least one phosphorus antiwear compound. The phosphorus antiwear compound may be an acid, salt or ester. In one embodiment, the phosphorus antiwear compound is in the form of a mixture of two or three, or two to four (typically two or three) phosphorus antiwear compounds. In some embodiments, the phosphorus antiwear compound is in the form of a mixture of phosphite and phosphate amine compounds.

In some embodiments, the phosphorus antiwear compound is a phosphite. Suitable phosphites include those having at least one hydrocarbyl group with 3 or 4 or more, or 8 or more, or 12 or more carbon atoms. The phosphite may be a mono-hydrocarbyl substituted phosphite, a di-hydrocarbyl substituted phosphite or a tri-hydrocarbyl substituted phosphite.

In one embodiment, the phosphite is sulfur-free, i.e., the phosphite is not a thiophosphite.

Phosphites may be represented by the formula:

Wherein at least one R may be a hydrocarbyl group containing at least 3 carbon atoms, and the other R groups may be hydrogen. In one embodiment, two of the R groups are hydrocarbyl groups and the third is hydrogen. In one embodiment, each R group is a hydrocarbyl group, i.e., the phosphite is a tri-hydrocarbyl substituted phosphite. The hydrocarbyl group may be an alkyl group, cycloalkyl group, aryl group, acyclic group, or mixtures thereof.

The R hydrocarbyl group may be linear or branched, typically linear, and may be saturated or unsaturated, typically saturated.

In one embodiment, the phosphorus antiwear compound may be a C3-8 hydrocarbyl phosphite or a mixture thereof, i.e., wherein each R may independently be hydrogen or a hydrocarbyl group having 3 to 8, or 4 to 6 carbon atoms, typically 4 carbon atoms. Typically, the C3-8 hydrocarbyl phosphite includes dialkyl phosphites, wherein each R is 1 to 14 carbon atoms, or 2 to 12 carbon atoms, or 3 to 8, or 4 to 6 carbon atoms. The dialkyl phosphite may be, for example, dibutyl phosphite or dioleyl phosphite. The C3-8 hydrocarbyl phosphite or C3-8 dialkyl phosphite may deliver at least 175ppm or at least 200ppm of the total amount of phosphorus delivered by the phosphorus antiwear compound. The C3-8 hydrocarbyl phosphite or dialkyl phosphite may deliver at least 45 wt.%, or 50 wt.% to 100 wt.%, or 50 wt.% to 90 wt.%, or 60 wt.% to 80 wt.% of the total phosphorous of the phosphorous antiwear compound.

In one embodiment, the phosphorus antiwear compound may be a C12-24 hydrocarbyl phosphite or a mixture thereof, i.e., wherein each R may independently be hydrogen or a hydrocarbyl group having from 12 to 24, or from 14 to 20 carbon atoms, typically from 16 to 18 carbon atoms. Typically, the C12-24 hydrocarbyl phosphite includes a C16-18 dialkyl phosphite. Examples of alkyl groups for R3, R4 and R5 include octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl or mixtures thereof. The C12-24 hydrocarbyl phosphite or C12-24 dialkyl phosphite may be present in the lubricant additive composition in an amount of from about 0.05% to about 1.0% by weight of the lubricant additive composition, or from about 0.1% to about 0.5% by weight of the lubricant additive composition.

In some embodiments, the phosphorus-containing compound may include a C3-8 hydrocarbyl phosphite and a C12-14 hydrocarbyl phosphite.

The phosphorus antiwear compound may comprise 0.1 wt% to 2 wt% of the additive composition, or even 0.1 wt% to 1.8 wt% of the lubricant additive composition, or 0.1 wt% to 1.4 wt% or 1.6 wt% of the lubricant additive composition, or even 0.1 wt% to 1 wt% or 1.2 wt% of the phosphite. The phosphorus antiwear compound may comprise from 0.1 wt% to 0.5 wt% of the additive composition, or even from 0.1 wt% to 0.4 wt%, or from 0.1 wt% to 0.2 wt% of the phosphite of the lubricant additive composition.

The phosphorus antiwear compound may be a phosphite composition that is the reaction product, e.g., condensation product, of monomeric phosphorous acid or an ester thereof with at least two alkylene glycols. In one embodiment, the aforementioned phosphite does not contain zinc.

By "monomeric" phosphorous acid or ester is meant a phosphorous acid or ester, typically containing one phosphorus atom, that can react with a glycol to form an oligomeric, polymeric, or other condensed species. The monomeric phosphorous acid or ester thereof may be phosphorous acid itself (H3 PO 3), although monomeric partial esters such as dialkyl phosphites may also be used for ease of handling or other reasons. The one or more alkyl groups may be relatively low molecular weight groups having 1 to 6 or 1 to 4 carbon atoms, such as methyl, ethyl, propyl or butyl, so that alcohols produced upon reaction with the alkylene glycol can be easily removed. Exemplary phosphate esters are dimethyl phosphite, and other phosphate esters include diethyl phosphite, dipropyl phosphite, dioleyl phosphite and dibutyl phosphite. Sulfur-containing analogs (e.g., thiophosphonites) may also be employed. Other esters include trialkyl phosphonites. Mixtures of dialkyl and trialkyl phosphonites may also be used. As mentioned above, in these materials, the alkyl groups may be the same or different, typically each alkyl group independently has from 1 to 6 or from 1 to 4 carbon atoms.

The monomeric phosphoric acid or ester will react or condense with at least two alkylene glycols to form a phosphorus antiwear compound, which may include a polymeric (or oligomeric) phosphoric acid ester and optionally a monomeric species. The first alkylene glycol (i) will be a1, 4-or 1, 5-or 1, 6-alkylene glycol. That is, there will be two hydroxyl groups in a1, 4 or 1,5 or 1,6 relationship with each other separated by a chain of 4, 5 or 6 carbon atoms, respectively. The first hydroxyl group may be literally on 1 carbon atom, that is, on the carbon of the alpha diol, or it may be on a higher numbered carbon atom. For example, the diol may also be a 2, 5-diol, or a 2, 6-diol, or a 2, 7-diol, or a 3, 6-diol, or a 3, 7-diol, or a 3, 8-diol, as will be apparent to those skilled in the art. The alkylene glycol may be branched (e.g., alkyl substituted) or unbranched, and in one embodiment is unbranched. Unbranched, i.e., branched diols (α, ω -diols) include 1, 4-butanediol, 1, 5-pentanediol, and 1, 6-hexanediol. Branched or substituted diols include 1, 4-pentanediol, 2-methyl-1, 5-pentanediol, 3-dimethyl-1, 5-pentanediol, 1, 5-hexanediol, 2, 5-hexanediol, and 2, 5-dimethyl-2, 5-hexanediol. Diols having one or more secondary hydroxyl groups (e.g., 2, 5-hexanediol) may be referred to as branched or substituted diols, even though the carbon chain itself may be linear. The positions of the hydroxyl groups in the 1,4, 1,5 or 1,6 positions (that is to say the positions relative to each other or the literal positions) may help to promote oligomerization with the phosphorus species rather than forming a cyclic structure (which would be sterically disadvantageous). In certain embodiments, the first alkylene glycol may be 1, 6-hexanediol.

If desired, the first alkylene dihydroxy compound (diol) may have additional hydroxyl groups, that is, more than two per molecule, or there may be exactly two hydroxyl groups present. In one embodiment, there are exactly two hydroxyl groups per molecule. If more than two hydroxyl groups are present, in the presence of less than 4 atoms separating any of the hydroxyl groups, care should be taken to ensure that there is no excessive cyclisation as might interfere with the polymerisation reaction. In addition, care should be taken to avoid excessive branching or crosslinking of the product, which can lead to the formation of undesirable gels. Such problems can be avoided by careful control of the reaction conditions, such as controlling the ratio of reagents and the order of addition, performing the reaction under suitable dilution conditions, and reacting under low acidity conditions. These conditions can be determined by one skilled in the art by only routine experimentation.

The phosphorous acid or ester is also reacted with the second alkylene glycol (ii). The second alkylene glycol is an alkyl-substituted 1, 3-propanediol having one or more of its alkyl substituents located on one or more of the carbon atoms of the propylene unit, the total number of carbon atoms in the alkyl-substituted 1, 3-propanediol being from 5 to 12 or from 6 to 12 or from 7 to 11 or from 8 to 18, or in certain embodiments 9. That is, the alkyl-substituted 1, 3-propanediol may be represented by the general formula:

Wherein each R group may be the same or different and may be hydrogen or an alkyl group, provided that at least 1R is an alkyl group and the total number of carbon atoms in the R groups is 2 to 9 or 3 to 9, such that the total carbon atoms in the diol will be 5 to 12 or 6 to 12, respectively, and the same is true for other ranges of total carbon. By analogy with the above-mentioned 1, 4-diols, 1, 5-diols or 1, 6-diols, reference herein to a1, 3-diol means that the two hydroxyl groups are in a1, 3 relationship to each other, that is, separated by a chain of 3 carbon atoms. Thus, 1, 3-diols may also be referred to as 2, 4-diols or 3, 5-diols. If the 1, 3-diol has one or more secondary hydroxyl groups, such molecules will be considered substituted diols. In one embodiment, the number of alkyl substituents is 2 and the total number of carbon atoms in the molecule is 9. Suitable substituents may include, for example, methyl, ethyl, propyl and butyl (in the form of their various possible isomers).

Examples of the second alkylene glycol may include 2, 2-dimethyl-1, 3-propanediol, 2-ethyl-2-butylpropane-1, 3-diol, 2-ethylhexyl-1, 3-diol, 2-dibutylpropane-1, 3-diol, 2-diisobutylpropane-1, 3-diol, 2-methyl-2-propylpropane-1, 3-diol, 2-propyl-propane-1, 3-diol, 2-butylpropane-1, 3-diol, 2-pentylpropane-1, 3-diol, 2-methyl-2-propylpropane-1, 3-diol, 2-diethylpropane-1, 3-diol, 2, 4-trimethylpentane-1, 3-diol, 2-methylpentane-2, 4-diol, 2, 4-dimethyl-2, 4-pentanediol, and 2, 4-hexanediol. It should be noted that for clarity, some of the foregoing nomenclature emphasizes the propane-1, 3-diol structure of the molecule. For example, 2-pentylpropyl-1, 3-diol may also be named 2-hydroxymethylhept-1-ol, but the latter nomenclature does not so clearly illustrate the 1, 3-nature of the diol.

The ratio of the relative molar amounts of the first alkylene glycol (i) and the second alkylene glycol (ii) may be 30:70 to 65:35, or alternatively 35:65 to 60:40, or 40:60 to 50:50, or 40:60 to 45:55. If the ratio is less than about 30:70, the resulting product may not fully exhibit the benefits of the disclosed technology, and if the ratio is greater than about 65:35, its compatibility with other components in the lubricant formulation may be reduced.

The ratio of the relative molar amount of monomeric phosphorous acid or ester thereof (a) to the total molar amount of alkylene glycol (b) may be from 0.9:1.1 to 1.1:0.9, or from 0.95:1.05 to 1.05:0.95, or from 0.98:1.02 to 1.02:0.98, or about 1:1. Reactions carried out at about equimolar ratios will tend to promote oligomer formation or polymer formation. The exact 1:1 ratio can theoretically lead to extremely long chain formation and thus to very high molecular weights. However, in practice, this is not generally achieved because competing reactions and incompleteness of the reactions will provide a material with a lower degree of polymerization, and some portion of the material will be in the form of cyclic monomers.

The reaction product will typically comprise a mixture of individual species, including some oligomeric or polymeric species as well as cyclic monomer species. The cyclic monomer species may contain 1 phosphorus atom and one alkylene group derived primarily from the 1, 3-diol (ii), since the 1, 3-diol is capable of participating in the formation of an oligomeric or cyclic ester. The oligomeric or polymeric species may generally comprise 2 or 3 to 20 phosphorus atoms, or alternatively 5 to 10 phosphorus atoms, which are linked together by alkylene groups derived from diols (i) and (ii) and may exhibit relatively preferential incorporation of 1,4-, 1, 5-or 1, 6-diols which are less prone to cyclisation with phosphorus to form cyclic monomeric species.

The product may be a mixture of substances that may be represented by the structure shown:

Wherein x and y represent the relative amounts of the two diols incorporated into the oligomer. The structures shown are not intended to indicate that the polymer is necessarily a block polymer, as the structures represented by the x and y brackets may be more or less randomly distributed, affected by or dependent upon the availability of the various glycol reactants. Each X is independently a terminal group, which may be, for example, an alkyl group (such as methyl) or a hydrogen atom or an OH group-terminated diol-derived structure. In the above schemes, diene (i) is selected as 1, 6-hexanediol and diene (ii) is selected as 2-butyl-2-ethyl-1, 3-propanediol for illustration purposes only. The corresponding structures and mixtures will be formed using different diols (i) and (ii).

The relative amounts of oligomeric and cyclic monomeric species in the reaction mixture will depend to some extent on the particular diol and reaction conditions selected. For reaction products prepared from 1, 6-hexanediol and 2-butyl-2-ethyl-1, 3-propanediol, as shown in the above structure, the amount of oligomerization product can be approximated as shown in the following table:

mol% of 1, 6-diol	30	40	50	60	65
						Weight% oligomer	52	58	62	70	71

And the amount of cyclic monomer may be 100% minus the percentage of oligomer. It is also possible that whatever the specific diol used, a mixture of oligomers and cyclic monomers having the weight percentages described above may be prepared. In certain embodiments, 55 to 60 weight percent of the product is in oligomeric form and 45 to 40 percent is in cyclic monomeric form. In some embodiments, the relative amounts of cyclic monomer species and oligomeric species are 1:3 to 1:1 by weight, or alternatively, 1:3 to 1:0.8.

The condensation reaction between phosphoric acid or ester and glycol may be accomplished by mixing the reagents and heating until the reaction is substantially complete. Typically, the first and second alkylene glycols may be mixed with the phosphorus compound at the same time or nearly the same time (i.e., typically prior to completion of the reaction with one of the alkylene glycols). Small amounts of alkaline substances, such as sodium methoxide, may also be present. If methyl phosphite is used as reagent, the substantial completion of the reaction may correspond to precipitation of methanol from the reaction mixture and cessation of distillation. Suitable temperatures include temperatures in the range of 100 ℃ to 140 ℃, such as 110 ℃ to 130 ℃ or 115 ℃ to 120 ℃. If the reaction temperature employed exceeds about 140 ℃, there may be a risk that the desired product may not be formed in useful yields or in useful purity, as competing reactions may occur. Typically, the reaction time can be up to 12 hours, depending on temperature, applied pressure (if any), agitation, and other variables. In some cases, a reaction time of 2 hours to 8 hours or 4 hours to 6 hours may be suitable.

Other monomers may be included in the reaction mixture if desired. In particular, it is sometimes considered advantageous to include polycarboxylic acids, such as dicarboxylic acids. For example, inclusion of relatively small amounts of tartaric or citric acid can provide products with useful properties. The amount of polyacid or diacid may be an amount suitable for incorporation of at least 1 or about 1 polycarboxylic or dicarboxylic acid monomer unit per product oligomer molecule. The amount of polyacid or diacid actually added to the reaction mixture may be greater than this amount. Without intending to be bound by any theory, it is believed that when a small amount of tartaric acid is present, it may be incorporated as a terminal unit of the polymer, possibly condensed with the OH groups of the alkylene glycol via an ester linkage. Such materials may exhibit good performance in terms of wear protection and corrosion inhibition and sealing properties. Suitable polyacids (or esters or anhydrides thereof) include maleic acid, fumaric acid, tartaric acid, citric acid, phthalic acid, terephthalic acid, malonic acid (e.g., esters), succinic acid, malic acid, adipic acid, oxalic acid, sebacic acid, dodecanedioic acid, glutaric acid, and glutamic acid. Another class of monomers that may be included are monocarboxylic acids containing a reactive hydroxyl group or reactive equivalents of such materials, such as anhydrides, esters, or lactones. Examples include glyoxylic acid, caprolactone, valerolactone and hydroxystearic acid.

The amount of the above phosphite product used in the lubricant may be an amount sufficient to provide the composition with 0.01 to 0.3 or 0.1 weight percent, or in other embodiments, 0.02 to 0.07 weight percent or 0.025 to 0.05 weight percent phosphorus. Of course, the actual amount of product corresponding to these amounts of phosphorus will depend on its phosphorus content. Suitable amounts of the ester product in the lubricant additive composition may range from 0.01 wt% to 1.0 wt%, or from 0.02 wt% to 0.5 wt%, or from 0.03 wt% to 0.30 wt%, or even from 0.05 wt% to 0.25 wt%.

While each of the above-described phosphorus antiwear compounds may be present alone in the lubricant additive composition, the lubricant additive composition may also include a mixture of two or more. In some embodiments, the phosphorus-containing compound can include a C3-8 hydrocarbyl phosphite and a phosphite product. In some embodiments, the phosphorus-containing compound can include each of a C3-8 hydrocarbyl phosphite, a C12 to C24 hydrocarbyl phosphite, and a phosphite product. In either case, the phosphorus antiwear compound should be present in an amount that delivers 100ppm to 4000ppm of phosphorus to the lubricant additive composition. In some embodiments, the at least one phosphorus antiwear compound may be present in an amount that delivers 125ppm to 1000ppm phosphorus or 150ppm to 800ppm phosphorus to the lubricant additive composition.

As further described, the lubricant additive composition may comprise a substantially sulfur-free alkyl phosphate. In this salt composition, at least 30 mole% of the phosphorus atoms are in the alkyl pyrophosphate structure, as opposed to the orthophosphate (or monomeric phosphate) structure. The percentage of phosphorus atoms in the pyrophosphate structure may be 30 to 100 mole%, or 40 to 90 mole%, or 50 to 80 mole%, or 55 to 70 mole%, or 55 to 65 mole%. The remaining amount of phosphorus atoms may be in the orthophosphate structure, or may be partially composed of unreacted phosphoric acid or other phosphorus species. In one embodiment, up to 60 mole% or up to 50 mole% of the phosphorus atoms are in the mono-or di-alkyl orthophosphate structure.

Substantially sulfur-free alkyl phosphates in the form of pyrophosphates (sometimes referred to as POP structures). In certain embodiments, at least 80 mole%, or at least 85%, 90%, 95%, or 99% of the alkyl groups in the alkyl phosphate will be primary alkyl groups. In some embodiments, the alkyl group will have from 4 to 22 carbon atoms, or from 4 to 20 carbon atoms, or from 4 to 18 carbon atoms, or even from 4 to 12 carbon atoms, or from 5 to 10 carbon atoms, or from 6 to 8 carbon atoms. Such groups include 2-butyl, 2-pentyl, 3-methyl-2-butyl, 2-hexyl, 3-hexyl, cyclohexyl, 4-methyl-2-pentyl, as well as other such primary groups having 6, 7, 8, 9, 10, 11 or 12 carbon atoms and isomers thereof. In some embodiments, the alkyl group will have a methyl branch at the α -position of the group, exemplified by a 4-methyl-2-pentyl (also known as 4-methylpent-2-yl) group.

Such alkyl (including cycloalkyl) groups will typically be provided by reaction of the corresponding alcohol or alcohols with phosphorus pentoxide (referred to herein as P ₂O₅, although it is recognized that more likely structures may be represented by P ₄O₁₀). Thus, alkyl phosphates may be prepared by reacting phosphorus pentoxide with a primary alcohol having 4 to 12 carbon atoms, and reacting the product thereof with a salified material, as described in further detail below.

Although pyrophosphate may be isolated from orthoesters if desired, it is also possible and commercially preferred to use a reaction mixture without isolation of components.

In one embodiment, the phosphorus antiwear compound may include a phosphorus-containing acid, salt or ester, or a mixture thereof. In one embodiment, the phosphorus antiwear compound is in the form of a mixture.

Phosphorus antiwear compounds may include those derived from phosphoric acid, phosphorous acid, thiophosphoric acid, or mixtures thereof.

In one embodiment, the phosphorus antiwear compound may include (i) a nonionic phosphorus compound, (ii) an amine salt of a phosphorus compound, or (hi) an ammonium salt of a phosphorus compound.

In one embodiment, the phosphorus antiwear compound may include an ammonium salt or amine salt of a phosphorus-containing acid or ester.

Amine salts of phosphoric acid or esters include phosphoric acid esters and amine salts thereof, dialkyldithiophosphoric acid esters and amine salts thereof, amine salts of phosphites, and amine salts of phosphorus-containing carboxylic acid esters, ethers, and amides, and mixtures thereof.

The alkyl group of the phosphorus antiwear compound may be 2 to 12 carbons, or 3 to 10, or 4 to 8 carbon atoms in length.

Amine salts of phosphoric acid or esters may be used alone or in combination.

In one embodiment, the amine salt of the phosphoric acid or ester comprises a partial amine salt, or a partial amine-metal salt compound, or mixtures thereof.

Pyrophosphate, phosphate or a mixture of phosphate esters is reacted with the salinated material. The salified material may be a metal to form a metal salt, or an amine to form an amine salt.

The metal of the metal salt includes aluminum, calcium, magnesium, strontium, chromium, iron, cobalt, nickel, zinc, tin, lead, manganese, silver, or mixtures thereof. In one embodiment, the metal is zinc.

The amine in the amine salt may be represented by R ² ₃ N, wherein each R ² is independently hydrogen or a hydrocarbyl group or an ester-containing group or an ether-containing group, provided that at least one R ² group is a hydrocarbyl group or an ester-containing group or an ether-containing group (i.e., not NH ₃). Suitable hydrocarbyl amines include primary amines having from 1 to 18 carbon atoms, or from 3 to 12 or from 4 to 10 carbon atoms, such as methylamine, ethylamine, propylamine, isopropylamine, butylamine and isomers thereof, pentylamine and isomers thereof, hexylamine and isomers thereof, heptylamine and isomers thereof, octylamine and isomers thereof, such as isooctylamine and 2-ethylhexylamine, and higher amines. Other primary amines include dodecylamine, fatty amines (e.g., n-octylamine, n-decylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine, n-octadecylamine, and oleylamine). Other useful fatty amines include commercially available fatty amines, e.gAmines (available from Akzo Chemicals, chicago, ill.) of Chicago, ill.) such as

C、O、OL、T、HT、S andSD, wherein the letter designation refers to a fatty group, such as a coco, oil, tallow, or stearyl group.

Secondary amines which may be used include dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentamine, dihexylamine, diheptylamine, methylethylamine, ethylbutylamine, bis-2-ethylhexyl amine, N-methyl-1-amino-cyclohexane,2C and ethylpentanamine. Secondary amines may be cyclic amines such as piperidine, piperazine and morpholine.

Suitable tertiary amines include tri-n-butylamine, tri-n-octylamine, tri-decylamine, tri-laurylamine, tri-hexadecylamine and dimethyloleylamineDMOD). Triisodecylamine or Tridecylamine (TRIDECYLAMINE) and isomers thereof may be used.

Examples of mixtures of amines include (i) amines having 11 to 14 carbon atoms on the tertiary alkyl primary group, (ii) amines having 14 to 18 carbon atoms on the tertiary alkyl primary group, or (iii) amines having 18 to 22 carbon atoms on the tertiary alkyl primary group. Other examples of tertiary primary amines include tertiary butylamine, tertiary hexylamine, tertiary octylamine (e.g., 1-dimethylhexylamine), tertiary decylamine (e.g., 1-dimethyloctylamine), tertiary dodecylamine, tertiary tetradecylamine, tertiary hexadecylamine, tertiary octadecylamine, tertiary tetracosanamine, and tertiary octacosanamine. In one embodiment, useful amine mixtures include "81R 'OR'.JMT”。81RJMT (both produced and sold by Rohm & Haas) can be a mixture of C11 to C14 tertiary alkyl primary amines and C18 to C22 tertiary alkyl primary amines, respectively.

In one embodiment, the amine salt of a phosphoric acid or ester as described above may include an amine having a primary tertiary alkyl group of about C _n to about C ₁₄, or a mixture thereof. In one embodiment, the amine salt of the phosphorus compound comprises an amine having a primary tertiary alkyl amine of about C ₁₄ to about C ₁₈ or a mixture thereof. In one embodiment, the amine salt of the phosphorus compound comprises an amine having a primary tertiary alkyl amine of about C ₁₈ to about C ₂₂ or a mixture thereof.

In one embodiment, the amine salt of a phosphoric acid or ester as described above may be a C ₁₄ to C ₁₈ alkylated phosphoric acid and81R (produced and sold by Rohm & Haas) which is a reaction product of the formula81R is a mixture of primary tertiary alkyl amines of C ₁₁ to C ₁₄. In other embodiments, the amine may be an ester-containing amine, such as an N-hydrocarbyl-substituted gamma-or delta-amino (thio) ester, which is thus a secondary amine. One or both of the O atoms of the ester group may be replaced by sulfur, but typically no sulfur atom may be present.

One or more additional substituents or groups may also be present at the α, β, γ, or δ positions of the amino ester. In one embodiment, such substituents are absent. In another embodiment, a substituent is present at the β position. That is, the substituent at the β -position of the chain may include an ester, thioester, carbonyl, or hydrocarbyl group. It will be understood to cover similar structures for delta-amino esters.

In one embodiment, the material may be a methylsuccinic diester having amine substitutions on the methyl groups. In certain embodiments, the material will be or will comprise 2- ((hydrocarbyl) -aminomethyl succinic acid dihydrocarbyl ester (which may also be referred to as dihydrocarbyl 2- ((hydrocarbyl) aminomethyl succinic acid ester).

The N-hydrocarbyl-substituted gamma-amino esters or gamma-amino thioester species disclosed herein can be prepared by Michael addition (Michael addition) of a primary amine, typically having a branched chain hydrocarbyl group as described above, with an ethylenically unsaturated ester or thioester of the type described above. In this case, the ethylenic unsaturation will be between the β and γ carbon atoms of the ester.

The N-hydrocarbyl-substituted delta-amino esters or delta-aminothioester materials disclosed herein can be prepared by reductive amination of an ester of a 5-oxo-substituted carboxylic acid or a 5-oxo-substituted thiocarboxylic acid. They can also be prepared by amination of esters of 5-halogen-substituted carboxylic acids or 5-halogen-substituted thiocarboxylic acids, or by reductive amination of esters of 2-amino-substituted adipic acids, or by alkylation of esters of 2-aminoadipic acids.

Further details of N-substituted gamma-amino esters and their synthesis can be found in WO2014/074335 at 2014, 5, 15, lu Borun (Lubrizol). Further details of N-substituted delta-amino esters and their synthetic details can be found in PCT application PCT/US2015/027958 by Lubrizol, filed on 4.28, and US 61/989306 filed on 5.6, 2015.

Any type of amine will react to neutralize one or more acidic groups on the phosphate component, which will contain pyrophosphate as described above, as well as any orthophosphate that may be present.

When the amine salt is the amine salt of the above-described phosphate, the amount of the amine salt used in the lubricant may be 0.05 to 2.0 wt%, or 0.75 to 1.5 wt%, or 0.1 to 1.2 wt%.

The amount of phosphorus antiwear agent may be suitable to provide phosphorus to the lubricant formulation in an amount of 200 parts per million to 3000 parts per million by weight (ppm).

When the lubricant composition is substantially sulfur-free (less than 250 parts per million, or less than 100 parts per million, or less than 50 parts per million, or less than 25 parts per million, or even completely free), the phosphorus antiwear agent may be a phosphate salt suitable for providing phosphorus to the lubricant formulation in an amount of 100 parts per million to 5000 parts per million, or 125 parts per million to 3000 parts per million, or 125 parts per million to 2000 parts per million, or 100 parts per million to 200 parts per million.

Antioxidant agent

The lubricant additive composition may also include antioxidants, for example, aromatic amine antioxidants, hindered phenol antioxidants (including ester-containing hindered phenol antioxidants), and sulfurized olefin antioxidants. These antioxidants may be present in an amount of 0.01 wt% to 5 wt%, or 0.15 wt% to 3 wt%, or 0.2 wt% to 1.5 wt%, or 0.2 wt% to 1 wt%, or 0.25 wt% to 0.7 wt%.

In one embodiment, the lubricant additive composition of the present invention includes an aryl amine antioxidant. The arylamine antioxidant may be phenyl-alpha-naphthylamine (PANA), or a hydrocarbyl substituted diphenylamine or mixtures thereof. The hydrocarbyl-substituted diphenylamines can include mono-or di-C4 to C16-, or C6 to C12-, or C9-alkyldiphenylamines. For example, the hydrocarbyl-substituted diphenylamine can be octyl diphenylamine or dioctyl diphenylamine, dinonyl diphenylamine, typically dinonyl diphenylamine.

When present, the arylamine antioxidant may be present at 0.1 wt% to 1.2 wt%, or 0.15 wt% to 0.8 wt%, or 0.2 wt% to 0.6 wt%, or 0.3 wt% to 0.5 wt% of the lubricant additive composition.

Hindered phenolic antioxidants often contain sec-butyl and/or tert-butyl groups as sterically hindered groups. The phenolic group is typically further substituted with a hydrocarbyl group and/or a bridging group attached to the second aromatic group. Examples of suitable hindered phenol antioxidants include 2, 6-di-tert-butylphenol, 4-methyl-2, 6-di-tert-butylphenol, 4-ethyl-2, 6-di-tert-butylphenol, 4-propyl-2, 6-di-tert-butylphenol or 4-butyl-2, 6-di-tert-butylphenol or 4-dodecyl-2, 6-di-tert-butylphenol. In one embodiment, the hindered phenol antioxidant may be an ester and may include, for example, irganox ^TM L-135 or butyl 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate from Ciba.

If present, the hindered phenol antioxidant may be present from 0.1 wt% to 1 wt%, or from 0.2 wt% to 0.9 wt%, or from 0.1 wt% to 0.4 wt%, or from 0.4 wt% to 1.0 wt% of the lubricant additive composition.

Antioxidants also include sulfurized olefins such as monosulfides or disulfides or mixtures thereof. These materials typically have a sulfur bond containing from 1 to 10 sulfur atoms, for example from 1 to 4 or 1 or 2 sulfur atoms. Substances that may be sulfided for use as a sulfiding antioxidant in the lubricant additive composition may include oils, fatty acids and esters, olefins and polyolefins prepared therefrom, terpenes, or diels-alder adducts. Details of methods of preparing certain such vulcanized materials can be found in U.S. Pat. nos. 3,471,404 and 4,191,659.

Sulfur-free detergent

The lubricant additive composition also includes a sulfur-free detergent composition. The sulfur-free detergent may be selected from salicylate, phenate or salicylate detergents. Typically, such detergents are metal-containing detergents, wherein the metal may be sodium, potassium, calcium, magnesium or mixtures thereof.

The sulfur-free metal-containing detergents used in the present invention may be overbased detergents, non-overbased detergents, or mixtures thereof. Typically, the detergent is highly alkaline.

The preparation of metal-containing detergents is known in the art. Patents describing the preparation of overbased metal-containing detergents include U.S. Pat. nos. 2,501,731;2,616,905;2,616,911;2,616,925;2,777,874;3,256,186;3,384,585;3,365,396;3,320,162;3,318,809;3,488,284; and 3,629,109.

The metal-containing detergent may be a non-overbased detergent (which may also be referred to as a neutral detergent). The TBN of the non-overbased may be from 20mg KOH/g to less than 200mg KOH/g, or from 30mg KOH/g to 100mg KOH/g, or from 35mg KOH/g to 50mg KOH/g. The TBN of the non-overbased metal-containing detergent may also be from 20mgKOH/g to 175mgKOH/g, or from 30mgKOH/g to 100mgKOH/g.

As used herein, the TBN values and associated ranges of TBNs quoted are based on "as is", i.e., containing conventional amounts of diluent oil. Conventional amounts of diluent oil typically range from 30 wt% to 60 wt% (typically 40 wt% to 55 wt%) of the detergent component.

The metal-containing detergent may be an overbased detergent having a TBN of, for example, greater than 200mgKOH/g (typically 250mgKOH/g to 600mgKOH/g, or 300mgKOH/g to 500 mgKOH/g).

Overbased metal-containing detergents may be formed by the reaction of an alkaline metal compound (e.g., an alkaline metal compound containing sodium, potassium, calcium, or magnesium) with an acidic detergent matrix. The acidic detergent matrix may comprise alkyl salicylic acid.

The basic metal compound is used to provide alkalinity to the detergent. The basic metal compound is a compound of a hydroxide or an oxide of a metal.

The oxides and/or hydroxides may be used alone or in combination. The oxide or hydroxide may be hydrated or dehydrated, although hydration is typical. In one embodiment, the basic metal compound may be calcium hydroxide, which may be used alone or in combination with other metal basic compounds. Calcium hydroxide is commonly referred to as lime. In one embodiment, the calcium basic compound may be calcium oxide, which may be used alone or in combination with other metal basic compounds.

Salicylate detergents are generally derived from para-hydrocarbyl phenols or generally alkyl phenols. Alkylphenols of this type are carboxylated to form salicylate detergents. Suitable alkyl salicylates include those alkylated with oligomers of propylene, oligomers of butene, especially tetramers and pentamers of n-butene, and those alkylated with alpha-olefins, isomerized alpha-olefins, and polyolefins such as polyisobutene.

The detergent may be borated or non-borated.

The chemical structure of salicylate detergents is known to those skilled in the art. A general disclosure of the detergents and their structures is provided under the sub-title 7.2.6 in the standard textbook entitled "lubricant chemistry and Process (CHEMISTRY AND Technology of Lubricants)", third edition, edited by R.M. Mortier and S.T. Orszulik, copyright owner 2010, pages 220 to 223.

In one embodiment, the sulfur-free metal-containing detergent may be a sodium, potassium, calcium or magnesium-containing detergent or a mixture thereof. Such detergents and their preparation are well known in the art, but may also include those developed hereafter. However, the TBN and metal ratio may be slightly different. A more detailed description of the expressions "metal ratio", TBN and "soap content" is known to the person skilled in the art and is explained in standard textbooks, e.g. "lubricant chemistry and technology", third edition, edited by r.m. mortier and s.t. orszulik, copyright owner 2010, pages 219 to 220, classification of detergents under sub-heading 7.2.5.

In one embodiment of the invention, the detergent is a calcium-containing detergent. In one embodiment, the detergent comprises or consists of a calcium salicylate detergent. The calcium-containing detergent is included in an amount that delivers up to 2000ppm of calcium, or 100ppm to 1000ppm, or 100ppm to 600ppm of calcium, or 100ppm to 250ppm, or even 400ppm to 750ppm of calcium to the composition.

Other additives

The lubricant additive composition may contain additives other than those listed above.

The lubricant additive composition may also contain a poly (meth) acrylate polymer viscosity modifier. As used herein, the following ranges of viscosity modifiers are measured by GPC using polystyrene standards having weight average molecular weights in the range of 350 to 100,000.

In one embodiment, the lubricant additive composition includes a linear poly (meth) acrylate polymer having a weight average molecular weight of 5,000 to 25,000, or 8000 to 20,000.

The linear poly (meth) acrylate polymer may be present in the lubricant additive composition from about 0.1 wt% to about 5wt%, or from 0.1 wt% to 4 wt%, or from 0.2 wt% to 3wt%, or from 0.5wt% to 3wt%, or from 1.0 wt% to 4 wt%, from 0.6 wt% to 4 wt%, or from 0.75 wt% to 3 wt%/or from 0.2 wt% to 0.75 wt% of the lubricant additive composition.

The poly (meth) acrylate polymer may be derived from a monomer composition comprising (a) 50 to 95 or 60 to 80 weight percent of an alkyl (meth) acrylate wherein the alkyl group of the (meth) acrylate has 10 to 15 carbon atoms, (b) 1 to 40 or 4 to 35 weight percent of an alkyl (meth) acrylate wherein the alkyl group of the (meth) acrylate has 1 to 9 carbon atoms, (c) 1 to 10 or 1 to 8 weight percent of a monomer having dispersant functionality, (d) 0 to 4, 0 to 2 or 0 weight percent of a vinyl aromatic monomer (typically styrene), and (e) 0 to 9 or 0 to 6 weight percent of an alkyl (meth) acrylate wherein the alkyl group of the (meth) acrylate has 16 to 18 carbon atoms. In one embodiment, the linear polymer may contain from 0wt% to 20wt% of a 16 to 18 alkyl (meth) acrylate.

In one embodiment, the linear polymer comprises a poly (meth) acrylate (typically a polymethacrylate) whose units are derived from a mixture of alkyl (meth) acrylate monomers containing (a) from 8 to 24, or from 10 to 18, or from 12 to 15 carbon atoms in the alcohol-derived portion of the ester group, and (b) from 6 to 11, or from 8 to 11, or 8 carbon atoms in the alcohol-derived portion of the ester group, and which has a 2- (C1-4 alkyl) substituent, and optionally at least one monomer selected from the group consisting of (meth) acrylates containing from 1 to 7 carbon atoms in the alcohol-derived portion of the ester group and which is different from (meth) acrylates (a) and (b), vinyl aromatic compounds (or vinyl aromatic monomers), and nitrogen-containing vinyl monomers, with the proviso that no more than 60 wt.%, or no more than 50 wt.%, or no more than 35 wt.% of the esters contain no more than 10 carbon atoms in the alcohol-derived portion of the ester group. Linear polymers of this type are described in more detail in U.S. Pat. No. 6,124,249 or EP 0 937769A1 [0019] and [0031] to [0067 ]. (when written as R' C (=o) -OR, "alcohol derived moiety" refers to the "-OR" moiety of an ester, whether OR not it is actually prepared by reaction with an alcohol). Optionally, the linear polymer may additionally contain a third monomer. The third monomer may be styrene or a mixture thereof. The third monomer may be present in an amount of 0% to 25% of the polymer composition, or 1% to 15% of the composition, 2% to 10% of the composition, or even 1% to 3% of the composition.

Typically, the molar ratio of ester (a) to ester (b) in the copolymer is in the range of 95:5 to 35:65, or 90:10 to 60:40, or 80:20 to 50:50.

The esters are typically aliphatic esters, typically alkyl esters. In one embodiment, the ester of (a) may be a C12-15 alkyl (meth) acrylate, and the ester of (b) may be 2-ethylhexyl (meth) acrylate.

In one embodiment, the ester groups in ester (a) contain branched alkyl groups. The ester groups may contain 2% to 65%, or 5% to 60% of ester groups having branched alkyl groups. Branched alkyl groups may be β -branched and may contain from 8 to 60, or from 8 to 30, or from 8 to 16 carbon atoms. For example, the branched alkyl groups may be derived from 2-ethylhexanol, 2-butyloctanol, 2-hexyldecanol, 2-octyldodecanol, 2-decyltetradecanol, or mixtures thereof, or may be commercially available alcohols, such as those available from SasolBranched guerbet alcohols.

The C1-4 alkyl substituents can be methyl, ethyl, and any of the isomers of propyl and butyl.

The linear poly (meth) acrylate may have a weight average molecular weight of 45,000 or less, or 35,000 or less, or 25,000 or less, or 8000 to 25,000, or 10,000 to 35,000, or 12,000 to 20,000.

The linear polymer may be referred to as a viscosity modifier, or dispersant viscosity modifier, because it may exhibit dispersant functionality. The reference herein to "dispersant viscosity modifiers" excludes dispersants, which are a separate class of compounds. The linear polymer may be used as a separate viscosity modifier (or dispersant viscosity modifier) present as 0.5 to 4 wt% of a linear (meth) acrylic polymer viscosity modifier having dispersant functionality, wherein the linear polymer has a weight average molecular weight of 5,000 to 25,000, or 10,000 to 20,000, and wherein the oil having lubricating viscosity has a kinematic viscosity at 100 ℃ of 4cSt to 6cSt (mm 2/s) and a viscosity index of 120 to 150.

In one embodiment, the lubricant additive composition may contain only two linear polymer viscosity modifiers having dispersant functionality, wherein the linear polymer has a weight average molecular weight of 5,000 to 25,000 or 10,000 to 20,000.

In one embodiment, the lubricant additive composition may comprise 0.1 wt% to 4 wt% (or 0.2 wt% to 3 wt%) of a linear (meth) acrylic polymer viscosity modifier having dispersant functionality, wherein the linear polymer has a weight average molecular weight of greater than 25,000 to 400,000 (or to 350,000), or 30,000 to 150,000. Linear (meth) acrylic polymers having a weight average molecular weight of greater than 25,000 to 400,000 (or to 350,000) can be considered to be chemically similar to linear (meth) acrylic polymers having a weight average molecular weight of 5,000 to 25,000, except for the weight average molecular weight.

The lubricant additive composition may include a linear polymer viscosity modifier having dispersant functionality comprising 0.1 wt% to 5 wt% (or 1 wt% to 4 wt%) of a linear (meth) acrylic polymer viscosity modifier having dispersant functionality, wherein the linear polymer has a weight average molecular weight of 10,000 to 20,000, and 0.1 wt% to 4 wt% (or 1 wt% to 3 wt%) of a linear (meth) acrylic polymer viscosity modifier having dispersant functionality, wherein the linear polymer has a weight average molecular weight of greater than 20,000 to 250,000 (or 30,000 to 150,000).

As described below, the molecular weight of the viscosity modifier has been determined using known methods, such as GPC analysis using polystyrene standards. Methods for determining the molecular weight of polymers are well known. For example, these methods are described (i) P.J.Flory, "PRINCIPLES OF STAR POLYMER CHEMISTRY", cornellUniversity Press 91953), chapter VII, pages 266 to 315, or (ii) Macromolecules, an Introduction to star polymer Science ", by F.A.Bovey and F.H.Winslow, ACADEMIC PRESS (1979), pages 296 to 312.

In one embodiment, the lubricant additive may further comprise a boron-containing compound.

The lubricant additive composition may contain a boron-containing compound in an amount sufficient to provide from about 75ppm to about 500ppm of boron to the lubricant additive composition, or from about 85ppm to about 450ppm, or from about 95ppm to about 350ppm of boron, or from about 100ppm to about 400ppm of boron to the lubricant additive composition.

Boron may be delivered by various types of boron-containing compounds.

The boron-containing compound may be a dispersant post-treated with a boron source.

The boron-containing compound may include boron-containing friction modifiers such as borated fatty epoxides, borated glycerol esters, and borated alkoxylated fatty amines.

The boron-containing compound may also include borated detergents. Borated detergents may include, for example, overbased borated materials, as described in U.S. Pat. nos. 5,403,501 and 4,792,410.

The boron-containing compound may also include a borate ester. The borate ester may be a compound represented by one or more of the following formulas:

wherein each R may independently be a hydrocarbyl group of the term as defined herein, and any two adjacent R groups may together form a cyclic group. Mixtures of two or more of the foregoing may be used. The total number of carbon atoms in the R groups in each formula should be sufficient to render the compound soluble in the base oil. Typically, the total number of carbon atoms in the R groups is at least about 3, and in one embodiment at least about 5, and in one embodiment at least about 8. There is no limit to the total number of carbon atoms required in the R group, but a practical upper limit is the absence of about 400 or about 500 carbon atoms.

In embodiments, each R may independently be a hydrocarbyl group containing from 1 to 14, or from 2 to 13, or even from 3 to 10 or 12 carbon atoms, provided that the sum of the total number of carbon atoms in all R is 3 or more, preferably 4 or more, and even more preferably 6 or more. In some embodiments, each R independently may be a C3 to C22, or C3 to C18, or C3 to C12 alkyl group. Examples of useful R groups include isopropyl, n-butyl, isobutyl, pentyl, 4-methyl-2-pentyl, 2-ethyl-1-hexyl, isooctyl, decyl, dodecyl, 2-propylheptyl, tetradecyl, 2-pentenyl, dodecenyl, phenyl, naphthyl, alkylphenyl and the like.

Suitable examples of borates include, for example, tripropyl borate, tributyl borate, tripentyl borate, trihexyl borate, triheptyl borate, trioctyl borate, trinonyl borate, and tridecyl borate. Examples of other borates may include, for example, compounds of formula I wherein each R is independently C3 to C22, or C3 to C18, or C3 to C12 alkyl, such as, for example, tri-2-ethylhexyl borate, tri (2-propylheptyl) borate, and mixtures thereof. In one embodiment, the borate may be a C8 borate or a C10 borate. In one embodiment, the borate ester may be tris (2-propylheptyl) borate. In some embodiments, the borate ester may be tri-2-ethylhexyl borate.

In one embodiment, the borated ester may be represented by the formula B (OC 5H 11) 3 or B (OC 4H 9) 3. In one embodiment, the borated ester may be tri-n-butyl borate.

In one embodiment, the borated ester may be a phenol compound represented by the formula:

Wherein in formula VII R ₁、R₂、R₃ and R ₄ are independently hydrocarbyl groups having from 1 to about 12 carbon atoms, and R ₅ and R ₆ are independently alkylene groups having from 1 to about 6 carbon atoms, and in one embodiment are alkylene groups having from about 2 to about 4 carbon atoms, and in one embodiment are alkylene groups having from about 2 or about 3 carbon atoms. In one embodiment, R ₁ and R ₂ independently contain from 1 to about 6 carbon atoms, and in one embodiment are each a tert-butyl group. In one embodiment, R3 and R4 are independently hydrocarbyl groups having from about 2 to about 12 carbon atoms, and in one embodiment from about 8 to about 10 carbon atoms. In one embodiment, R5 and R6 are independently- -CH2CH2- -or- -CH2CH2CH2- -.

In one embodiment, the borated ester may be a compound represented by the formula:

Wherein in formula IX, each R is independently hydrogen or a hydrocarbyl group. Each of the hydrocarbyl groups may contain from 1 to about 12 carbon atoms, and in one embodiment from 1 to about 4 carbon atoms. An example is 2,2' -oxy-bis- (4, 6-trimethyl-1, 3, 2-dioxaborolan).

The borate ester may be used in the lubricant additive composition in an amount of about 0.2 wt.% or 0.3 wt.% to about 2.0 wt.%, or in some cases about 0.35 wt.% to 2.0 wt.%, and in one embodiment about 0.25 wt.% to about 1.0 wt.%, and in one embodiment about 0.25 wt.% to about 0.75 wt.%, based on the weight of the lubricant additive composition.

In one embodiment, the lubricant additive composition may include an ester of a polyol and an aliphatic carboxylic acid having from 12 to 24 carbon atoms.

Polyols include diols, triols and alcohols having a higher number of alcohol OH groups. Polyhydric alcohols include ethylene glycol, including diethylene glycol, triethylene glycol and tetraethylene glycol, propylene glycol, including dipropylene glycol, tripropylene glycol and tetrapropylene glycol, glycerol, butylene glycol, hexylene glycol, sorbitol, arabitol, mannitol, sucrose, fructose, glucose, cyclohexanediol, erythritol, and pentaerythritol, including dipentaerythritol and tripentaerythritol, preferably diethylene glycol, triethylene glycol, glycerol, sorbitol, pentaerythritol and dipentaerythritol.

The aliphatic carboxylic acids forming the esters are those acids containing from 12 to 24 carbon atoms. Such acids may be characterized by the following general formula R1- (CO) OH, wherein R1 is a hydrocarbyl group, which may be a straight chain hydrocarbyl group, a branched or cyclic hydrocarbyl group, or mixtures thereof. Straight-chain hydrocarbyl groups containing from 12 to 24 carbon atoms are preferred, for example, straight-chain hydrocarbyl groups containing from 14 to 20 or 16 to 18 carbon atoms. Such acids may also be used in combination with acids having more or less carbon atoms.

Typically, the acid R1- (CO) OH is a monocarboxylic acid, as polycarboxylic acids tend to form polymer products if the reaction conditions and the amounts of reactants are not carefully adjusted. However, mixtures of monocarboxylic acids and small amounts of dicarboxylic acids or anhydrides can be used to prepare esters. Examples of carboxylic acids include dodecanoic acid, stearic acid, lauric acid, behenic acid, and oleic acid.

The aforementioned esters are in particular monoesters of such polyols and such carboxylic acids. The preferred ester is glycerol monooleate. It will be appreciated that, as with other such materials, glycerol monooleate is on its commercial scale as a mixture of such materials including, for example, glycerol, oleic acid, other long chain acids, glycerol dioleate and glycerol trioleate. It is believed that the commercial material comprises about 60 ± 5% by weight of the chemical "glycerol monooleate", as well as 35 ± 5% glycerol dioleate and less than about 5% trioleate and oleic acid. The amount of monoester described below is calculated based on the actual correction amount of polyol monoester present in any such mixture.

The amount of the foregoing esters in the lubricant additive composition is typically on the order of about 0.01 wt.% to about 1.0 wt.% of the lubricant additive composition, but may also be about 0.05 wt.% to about 0.5 wt.%, or 0.8 wt.%, or about 0.1 wt.% to about 0.6 wt.%.

In addition to the foregoing esters, the lubricant additive composition may also contain esters of alcohols with aliphatic carboxylic acids containing from about 4 to about 8 carbon atoms.

Alcohols include both monohydric and polyhydric alcohols (polyhydric alcohol) (i.e., polyols). The carbon atoms of the alcohol may be linear, branched, or mixtures thereof.

Suitable polyols are the same as described above.

When branched, the alcohol may be a guerbet alcohol or a mixture thereof. Guerbet alcohols may have alkyl groups including 1) alkyl groups containing C15-16 polymethylene groups such as 2-C1-15 alkyl-hexadecyl groups (e.g., 2-octylhexadecyl) and 2-alkyl-octadecyl groups (e.g., 2-ethyloctadecyl, 2-tetradecyl-octadecyl, and 2-hexadecyl-octadecyl), 2) alkyl groups containing C13-14 polymethylene groups such as 1-C1-15 alkyl-tetradecyl groups (e.g., 2-hexyltetradecyl, 2-decyltridecyl, and 2-undecyltridecyl) and 2-C1-15 alkyl-hexadecyl groups (e.g., 2-ethyl-hexadecyl and 2-dodecylhexadecyl), 3) alkyl groups containing C10-12 polymethylene groups such as 2-C1-15 alkyl-dodecyl groups (e.g., 2-octyldodecyl) and 2-C1-15 alkyl-dodecyl groups (e.g., 2-hexyldodecyl and 2-octyldodecyl), 2-C1-15 alkyl-hexadecyl groups (e.g., 2-decyl) and 2-decyl groups (e.g., 2-decyltetradecyl) and 2-decyl groups (e.g., 2-decyl) and 2-decyl groups, such as 2-C1-15 alkyl-decyl groups (e.g., 2-octyldecyl) and 2, 4-di-C1-15 alkyl-decyl groups (e.g., 2-ethyl-4-butyl-decyl groups), 5) alkyl groups containing C1-5 polymethylene groups, such as 2- (3-methylhexyl) -7-methyl-decyl and 2- (1, 4-trimethylbutyl) -5, 7-trimethyl-octyl groups, and 6) and mixtures of two or more branched alkyl groups, such as alkyl residues corresponding to oxo alcohols of propylene oligomers (from hexamer to undecene), ethylene/propylene (molar ratio 16:1-1:11) oligomers, isobutylene oligomers (from pentamer to octamer), C5-17 alpha-olefin oligomers (from dimer to hexamer).

Examples of suitable branched monoalcohols include 2-ethylhexanol, 2-butyloctanol, 2-hexyldecanol, 2-octyldodecanol, 2-decyltetradecanol, isotridecanol, isooctanol, oleyl alcohol, guerbet alcohol, or mixtures thereof. Examples of monohydric linear alcohols include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, or mixtures thereof. In one embodiment, the monohydric alcohol contains from 6 to 30, or from 8 to 20, or from 8 to 15 carbon atoms (typically from 8 to 15 carbon atoms).

The aliphatic carboxylic acids forming the esters are those acids containing from 4 to 8 carbon atoms. Although aliphatic, the aliphatic carboxylic acids may contain ethylenically unsaturated groups along the C4 to C8 alkyl group backbone. In addition, such acids may be monocarboxylic or dicarboxylic acids or anhydrides or mixtures thereof. Examples of carboxylic acids include, for example, succinic acid, maleic acid, fumaric acid, glutaconic acid, glutaric acid, adipic acid, citraconic acid, mesaconic acid, pimelic acid, suberic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, and the like.

Particularly preferred esters may be adipates such as, for example, C8-13 or C8-12 adipates, such as diisooctyl adipate or ditridecyl adipate. Other esters may include, for example, pentaerythritol, neopentyl and trimethylol esters.

The amount of the foregoing esters in the lubricant additive composition is typically on the order of about 0.1 to about 3.0 weight percent of the lubricant additive composition, but may also be about 0.2 to about 2.5 weight percent, or about 0.3 to about 2.0 weight percent.

The carboxylic acid esters are prepared by the well known reaction of at least one carboxylic acid (or reactive equivalent thereof, such as an ester, halide or anhydride) with at least one of the above-mentioned hydroxy compounds.

Another component of the lubricant additive composition may be a metal deactivator. Examples of such materials include 2, 5-dimercapto-1, 3, 4-thiadiazole and/or derivatives thereof. Such materials are described in European patent publication 0761805, which is incorporated herein by reference.

The metal deactivators useful herein reduce corrosion of metals such as copper. Metal deactivators are also known as metal deactivators. These metal deactivators are typically nitrogen and/or sulfur containing heterocyclic compounds such as dimercaptothiadiazoles, triazoles, aminothiodiazoles, imidazoles, thiazoles, tetrazoles, hydroxyquinolines, oxazolines, imidazolines, thiophenes, indoles, indazoles, quinolines, benzoxazines, dithiols, oxazoles, pyridines, piperazines, triazines, and derivatives of any one or more thereof. The metal deactivator preferably comprises at least one triazole, which may be substituted or unsubstituted. Examples of suitable compounds are benzotriazole, alkyl-substituted benzotriazoles (e.g. tolyltriazole, ethylbenzotriazole, hexylbenzotriazole, octylbenzotriazole, etc.), aryl-substituted benzotriazoles (e.g. phenolbenzotriazole, etc.), and alkylaryl-or aralkyl-substituted benzotriazoles and substituted benzotriazoles, wherein the substituents may be hydroxy, alkoxy, halogen (especially chlorine), nitro, carboxy and carboxyalkoxy. Preferably, the triazole is a benzotriazole or an alkylbenzotriazole in which the alkyl group contains from 1 to about 20 carbon atoms, preferably from 1 to about 8 carbon atoms. Benzotriazole and tolyltriazole are useful.

In one embodiment, the metal deactivator is the reaction product of a dispersant and dimercaptothiadiazole. Dispersants can generally be characterized as the reaction product of a carboxylic acid with an amine and/or an alcohol. These reaction products are commonly used in the lubricant field as dispersants, sometimes collectively referred to as dispersants, although in fact they may have other uses in addition to or in place of dispersants. The carboxylic acid dispersants include succinimide dispersants, ester-type dispersants, and the like. Succinimide dispersants are typically the reaction of a polyamine with an alkenyl succinic anhydride or acid. The ester type dispersant is the reaction product of an alkenyl succinic anhydride or acid and a polyol compound. The reaction product may then be further treated with an amine, such as a polyamine. Examples of useful dispersants are disclosed in U.S. Pat. nos. 3,219,666 and 4,234,435, which are incorporated herein by reference. Useful dispersants also include ashless dispersants as discussed below. Typically, the reaction between the dispersant and dimercaptothiadiazole occurs by mixing the dispersant and dimercaptothiadiazole and heating to a temperature greater than about 100 ℃. U.S. patent nos. 4,140,643 and 4,136,043 describe compounds prepared by the reaction of such dispersants with dimercaptothiadiazoles. These patents are incorporated herein by reference for their disclosure of dispersants, dimercaptothiadiazoles, methods of reacting the two, and products obtained from such reactions.

In one embodiment, the metal deactivator is the reaction product of phenol and dimercaptothiadiazole. The phenol is preferably an alkylphenol in which the alkyl group contains at least about 6, preferably from 6 to about 24, more preferably from about 6 or from about 7 to about 12 carbon atoms. The aldehyde is preferably an aldehyde or aldehyde synthon containing from 1 to about 7 carbon atoms, such as formaldehyde. Preferably, the aldehyde is formaldehyde or paraformaldehyde. The aldehyde, phenol and dimercaptothiadiazole are typically reacted by mixing them at a molar ratio of about 0.5 moles to about 2 moles of phenol and about 0.5 moles to about 2 moles of aldehyde per mole of dimercaptothiadiazole at a temperature up to about 150 ℃, preferably about 50 ℃ to about 130 ℃. Preferably, the three reagents are reacted in equal molar amounts.

In one embodiment, the metal deactivator is a bis (hydrocarbyl dithio) thiadiazole. Preferably, each hydrocarbyl group is independently an alkyl, aryl, or aralkyl group having from 6 to about 24 carbon atoms. Each hydrocarbyl group may independently be a tertiary octyl, nonyl, decyl, dodecyl or ethylhexyl group. The metal deactivator may be bis-2, 5-tert-octyl-dithio-1, 3, 4-thiadiazole or a mixture thereof with 2-tert-octylthio-5-mercapto-1, 3, 4-thiadiazole. These materials are commercially available under the trade name Amoco 150, which is available from Amoco chemicals company (Amoco Chemical Company). These dithiothiadiazole compounds are disclosed as component (d) in PCT publication WO 88/03551, which is incorporated by reference for the dithiothiadiazole compounds disclosed therein. In a preferred embodiment, the metal deactivator is a dimercaptothiadiazole derivative. The following D-1 and D-2 are specific examples.

Example D-1

Oxidative coupling of 2, 5-dimercapto-1, 3, 4-thiadiazole with tertiary nonylthiol, 100% chemicals, 36% S,64% N.

Example D-2

The heptylphenol was coupled with 2, 5-dimercapto-1, 3, 4-thiadiazole using formaldehyde (thiadiazole generated in situ), 20% oil, 17.75% S,5.5% N.

When used, the amount of metal deactivator in the lubricant additive composition may generally be in the range of from about 0.01 to about 0.5 weight percent of the lubricant additive composition. In some embodiments, the amount of metal deactivator may be in the range of about 0.02 wt.% to about 0.42 wt.%, or about 0.03 wt.% to about 0.33 wt.%, or about 0.04 wt.% to about 0.24 wt.% of the lubricant additive composition.

Another component of the present invention may be a borated epoxide containing from 12 to 24 carbon atoms. This material may alternatively be described as a borate ester of an vicinal diol containing 12 to 24 carbon atoms. Such materials may be represented by the following structure:

Wherein R ¹、R²、R³ and R ⁴ are each independently hydrogen or an aliphatic radical, or any two of them together with the carbon atom or atoms to which they are attached form a cyclic radical. Preferably, at least one of the R groups may be an alkyl group containing at least 8 or at least 10 carbon atoms. In one embodiment, one of the R groups is such an alkyl group, and the remaining R groups are hydrogen. The borated epoxide is described in detail in U.S. patent No. 4,584,115. Borated epoxides are typically prepared by reacting an epoxide with a boron source such as boric acid or diboron trioxide. The borated epoxide is not an epoxide itself, but rather is the ring-opening boron-containing reaction product of an epoxide. Suitable epoxides include commercially available mixtures of C _14-16 or C _14-18 or C _16-18 epoxides, which are commercially available from Elf-Atochem or Union Carbide and can be prepared from the corresponding olefins by known methods. Purified epoxy compounds, such as 1, 2-epoxyhexadecane, are available from aldrich chemical company (ALDRICH CHEMICALS). The borated compound is prepared by blending the boron compound and epoxide and heating at a suitable temperature (typically 80 to 250 ℃) until the desired reaction occurs. Inert liquids, such as toluene, xylene or dimethylformamide, may be used as reaction medium. Water is formed during the reaction and is usually distilled off. Alkaline reagents may be used to catalyze the reaction. The preferred borated epoxide may be a borated epoxide of predominantly 16 carbon olefins. The amount of borate epoxide may be 0.01 or 0.05 to 0.5 or 1.0 parts by weight of the composition, or alternatively, 0.1 to 0.9%.

The lubricant additive composition preferably exhibits a conductivity of at most 1x 10-9S/cm at 100 ℃ and 500V, as measured by ASTM D2624, or a conductivity of 9.5x10-10S/cm, or 9x 10-10S/cm, or 8.5x10-10S/cm, or 8x10-10S/cm, or 7.0x10-10S/cm, or 6.5x10-10S/cm, or 6.0x10-10S/cm, or 5.5x10-10S/cm, or 5.0x10-10S/cm, as measured by ASTM D2624. It is highly preferred that the lubricant additive composition does not have electrical conductivity, but in practice electrical conductivities on the order of 4.0x10-10 or 4.5x10-10 can be achieved at 100 ℃.

In one embodiment, the lubricant additive composition is substantially free of friction modifiers. In some embodiments, the lubricant additive composition is completely free of friction modifiers.

When added to a base oil, the lubricant additive composition may be in the form of a concentrate and/or in the form of a fully formulated lubricant. That is, the lubricant additive composition may be added to a base oil to prepare a lubricating composition.

Base oil

Base oils may be defined as specified in the american petroleum institute (American Petroleum Institute) (API) base oil interchangeability guidelines (Base Oil Interchangeability Guidelines). Five base oils are group I (sulfur content >0.03 wt.% and/or <90 wt.% saturates, viscosity index 80-120), group II (sulfur content <0.03 wt.% and >90 wt.% saturates, viscosity index 80-120), group III (sulfur content <0.03 wt.% and >90 wt.% saturates, viscosity index > 120), group IV (all Polyalphaolefins (PAO)), group V (all other oils not included in groups I, II, III or IV). The base oil may include, for example, API group I, group II, group III, group IV oils, or mixtures thereof.

Typically, the base oil is an API group I, group II, group III, group IV oil or mixtures thereof. Alternatively, the base oil may be an API group II, group III, group IV oil or mixtures thereof.

In one embodiment, the base oil may be prepared by a Fischer-Tropsch gas-liquid synthesis procedure, as well as other gas-liquid oils.

In one embodiment, the base oil may be an API group IV oil. The amount of group IV oil may be 0 wt% to 20 wt%, or 0.1 wt% to 20 wt%, or 1 wt% to 15 wt%, or 5wt% to 10 wt% of the lubricant additive composition.

The amount of base oil present is typically the balance remaining after subtracting the sum of the amounts of the lubricant additives of the present invention from 100 wt.%. If the lubricant additive composition is in the form of a concentrate (which may be combined with a base oil to form a finished lubricant in whole or in part), the ratio of lubricant additive composition to base oil and/or diluent oil includes a range of 1:99 to 99:1, or 2:98 to 98:2, or 5:95 to 95:5, or 10:90 to 90:10, or 15:85 to 85:15, or 20:80 to 80:20 by weight.

According to ASTM D445, a lubricating composition containing a lubricant additive composition may have a kinematic viscosity at 40 ℃ of from 10cSt to 30cSt, or for example from 14cSt to 25cSt, or even from 15cSt to 22cSt, or from 9cSt to 25cSt or 22cSt, or for example from 10cSt to 25cSt or 22cSt, or even from 14cSt to 25cSt or 22cSt, or from 18cSt to 22 cSt.

The lubricating composition containing the lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 25cSt according to ASTM D445. According to ASTM D445, a lubricating composition containing a lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 15 cSt. According to ASTM D445, a lubricating composition containing a lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 12 cSt. According to ASTM D445, a lubricating composition containing a lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 9 cSt. The lubricating composition containing the lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 7cSt according to ASTM D445. According to ASTM D445, a lubricating composition containing a lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 6 cSt. According to ASTM D445, a lubricating composition containing a lubricant additive composition may have a kinematic viscosity at 100 ℃ of from 2cSt to 4 cSt.

When the lubricant additive composition is in the form of a lubricating composition, the lubricant additive composition will be suitable for lubricating a drive train of an electric vehicle, and in particular a gearbox of an electric motor in an electric vehicle. In particular, the lubricant additive composition will be suitable for lubricating a transmission in a vehicle having an electric motor, which may be an all-electric vehicle or a hybrid electric vehicle having both an electric motor and an engine powered by hydrocarbon or other fuel.

Specifically, the disclosed technology provides a method of lubricating a driveline power transmission device comprising supplying to the driveline power transmission device a lubricating composition as described herein, i.e., a lubricating composition containing a base oil, a succinimide dispersant, an azole corrosion inhibitor, a phosphorus antiwear compound, and an antioxidant, and operating the driveline power transmission device for a time sufficient to allow the lubricating composition to achieve the improved results as described herein.

Specifically, the disclosed technology provides a method of lubricating a driveline power transmission device comprising supplying to the driveline power transmission device a lubricating composition as described herein, i.e., a lubricating composition containing a base oil, a succinimide dispersant, an azole corrosion inhibitor, a phosphorus antiwear compound, an antioxidant, and a viscosity modifier, and operating the driveline power transmission device for a time sufficient to allow the lubricating composition to achieve improved results as described herein.

The driveline power transmission may include at least two gears, such as in a gearbox (e.g., manual transmission) of the vehicle or in an axle or differential, or in other driveline power transmission devices. The driveline power transmission may also include a bearing. The rolling elements of the bearing may be cylindrical or spherical in design. The lubricated gear may include a hypoid gear (amboid) or a spiral bevel gear or more commonly a hypoid gear, such as, for example, a hypoid gear in a drive shaft. The shaft may have a gear ratio of 2:1 to 8:1, and the diameter of the ring gear may be about 13cm to 64cm. The axle may incorporate an open differential or some type of traction-enabling device. The shaft may be part of a transmission system having one or more drive shafts, such as a tandem or triple joint design, where the shaft may be coupled with a power divider. Applications for these axles include light vehicles, medium-sized vehicles, and heavy vehicles (e.g., professional or long haul services), and may be used on-road or off-road. The axle may be from a conventional petroleum-powered vehicle, may be from an electrically-driven vehicle, or a hybrid vehicle thereof. The electric drive shaft may combine the motor, power electronics, and transmission in a single unit, directly powering the vehicle's axle.

Accordingly, one aspect is a method of lubricating an electric vehicle comprising supplying a driveline of an electric vehicle with a lubricating composition containing a lubricant additive composition as described herein and operating the driveline.

Another aspect is a method of lubricating a transmission, particularly a transmission in a vehicle having an electric motor, the method comprising supplying to the transmission a lubricating composition containing a lubricant additive composition as described herein, and operating the transmission.

The lubricant should be able to meet the aspects expected for the driveline power transmission device during its normal operation.

Suitable transmissions for which the lubricant additive composition may be used include automatic transmissions and dual clutch transmissions. The transmission may or may not include a shift clutch, and in the case of a transmission including a shift clutch, the clutch may be a dry clutch or a wet clutch. In one embodiment, the lubricant may be used on a transmission that does not contain a shifting clutch. In another embodiment, the lubricant additive composition may be used in a transmission having a wet clutch. In yet another embodiment, the lubricant additive composition may be used in a transmission having a dry clutch.

The driveline device may be a manual transmission that may or may not include a synchronizer system or shaft. In one embodiment, the driveline device includes a synchronizer or shaft.

In one embodiment, the driveline device includes a synchronizer. The synchronizer system may have an operating surface comprising brass, carbon, molybdenum, phenolic resin, or sintered metal (typically bronze) or mixtures thereof.

As used herein, the term "condensation product" is intended to encompass esters, amides, imides, and other such materials that can be prepared by the condensation reaction of an acid or a reactive equivalent of an acid (e.g., an acid halide, anhydride, or ester) with an alcohol or amine, whether or not the condensation reaction is actually performed to directly produce the product. Thus, for example, a particular ester may be prepared by transesterification rather than directly by condensation. The resulting product is still considered a condensation product.

Unless otherwise indicated, the amounts of each chemical component described do not include any solvents or diluent oils that may typically be present in a commercial material, i.e., on an active chemical basis. However, unless otherwise indicated, each chemical or composition referred to herein should be construed as a commercial grade material that may contain isomers, byproducts, derivatives, and other such materials that are generally understood to be present in the commercial grade.

As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, as is well known to those skilled in the art. In particular, it refers to a group having a carbon atom directly attached to the rest of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include:

hydrocarbon substituents, i.e., aliphatic (e.g., alkyl or alkenyl), cycloaliphatic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic, aliphatic, and cycloaliphatic-substituted aromatic substituents, as well as cyclic substituents, wherein the ring is completed through another portion of the molecule (e.g., two substituents together form a ring);

Substituted hydrocarbon substituents, i.e., substituents containing non-hydrocarbon groups that, in the context of the present invention, do not alter the primary hydrocarbon nature of the substituent (e.g., halogen (especially chlorine and fluorine), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy);

hetero substituents, i.e. substituents which, although having predominantly hydrocarbon character in the context of the present invention, contain atoms other than carbon in a ring or chain otherwise composed of carbon atoms and encompass substituents such as pyridyl, furyl, thienyl and imidazolyl. Heteroatoms include sulfur, oxygen, and nitrogen. Typically, no more than two or no more than one non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group, alternatively, no non-hydrocarbon substituent may be present in the hydrocarbyl group.

It is known that some of the above materials may interact in the final formulation such that the components of the final formulation may differ from those originally added. For example, metal ions (e.g., metal ions of detergents) may migrate to other acidic or anionic sites of other molecules. The products formed thereby, including those formed when the compositions of the present invention are used for their intended purpose, may not be readily described. However, all such modifications and reaction products are intended to be included within the scope of the present invention, which includes compositions prepared by mixing the above-described components.

As used herein, the term "about" means that a given amount of a value is within ±20% of the stated value. In other embodiments, the value is within ±15% of the specified value. In other embodiments, the value is within ±10% of the specified value. In other embodiments, the value is within ±5% of the specified value. In other embodiments, the value is within ±2.5% of the specified value. In other embodiments, the value is within ±1% of the specified value.

In addition, as used herein, the term "substantially" means that a given number of values is within ±10% of a specified value. In other embodiments, the value is within ±5% of the specified value. In other embodiments, the value is within ±2.5% of the specified value. In other embodiments, the value is within ±1% of the specified value.

In various embodiments, the lubricating composition may have a composition as set forth in the following table:

The invention herein may be used to lubricate an automatic transmission for a hybrid electric vehicle, as better understood with reference to the following clauses:

Clause 1 is a lubricant composition comprising (a) an oil of lubricating viscosity, (b) a dispersant, (c) a triazole corrosion inhibitor, (d) a phosphorus-containing antiwear compound, (e) an antioxidant, and (f) a sulfur-free detergent, wherein the lubricant composition contains no more than 40ppm sulfur, or no more than 30ppm sulfur, or no more than 20ppm sulfur.

Clause 2 the lubricant composition of clause 1, wherein the sulfur-free detergent comprises or consists of a salicylate detergent.

Clause 3 the lubricant composition of any preceding clause, wherein the sulfur-free detergent comprises or consists of calcium salicylate, and the calcium salicylate detergent is present in an amount sufficient to deliver up to 2000ppm, or 100ppm to 1000ppm, or 100ppm to 600ppm, or 100ppm to 250ppm, or 400ppm to 750ppm of calcium to the lubricant composition.

Clause 4 the lubricant composition of any preceding clause, wherein the phosphorus antiwear compound comprises a dialkyl phosphite having the formula:

Wherein R3 and R4 are independently alkyl groups having 1 to 24 carbon atoms.

Clause 5 the lubricant composition of clause 4, wherein the dialkyl phosphite comprises or consists of dibutyl hydrogen phosphite.

Clause 6 the lubricant composition of any preceding clause, wherein the phosphorus-containing antiwear compound comprises or consists of a phosphonate.

Clause 7, wherein the phosphonate comprises the reaction product of (a) a monomeric phosphorous acid or ester thereof and (b) at least two alkylene glycols, a first alkylene glycol (i) having two hydroxyl groups in a 1,4 or 1,5 or 1,6 relationship, and a second alkylene glycol (ii) being an alkyl-substituted 1, 3-propanediol, wherein one or more alkyl substituents of the alkyl substituents are located on one or more carbon atoms of the propylene unit, the total number of carbon atoms in the alkyl-substituted 1, 3-propanediol being from about 5 to about 12, wherein the ratio of the relative molar amount of monomeric phosphorous acid or ester thereof (a) to the total alkylene glycol (b) is from about 0.9:1.1 to about 1.1:0.9, and wherein the ratio of the relative molar amount of the first alkylene glycol (i) to the alkyl-substituted 1, 3-propanediol (ii) is from about 30:70 to about 65:35.

Clause 8-the lubricant composition of any preceding clause, wherein the dispersant comprises or consists of a succinimide dispersant having a number average molecular weight of 750 to 2200, or 750 to 1600, or 950 to 1550.

Clause 9 the lubricant composition of any of clauses 1 to 7, wherein the dispersant comprises or consists of an olefin polymer dispersant.

Clause 10 the lubricant composition of clause 9, wherein the dispersant comprises or consists of an ethylene/propylene copolymer dispersant.

Clause 11 the lubricant composition of any of clauses 1-8, wherein the dispersant comprises a borated PIB succinimide dispersant having a number average molecular weight of 1000.

Clause 12 the lubricant composition of clause 11, wherein the dispersant comprises a non-borated PIB succinimide dispersant having a number average molecular weight of 1550.

Clause 13 the lubricant composition of any of the preceding clauses, wherein the dispersant comprises polyisobutylene succinic anhydride (PIBSA) prepared by a thermal process.

Clause 14 the lubricant composition of any preceding clause, wherein the triazole corrosion inhibitor comprises or consists of 1,2, 4-triazole.

Clause 15-the lubricant composition of any of the preceding clauses, wherein the triazole corrosion inhibitor comprises or consists of N, N-bis (2-ethylhexyl) - [ (1, 2, 4-triazol-1-yl) methyl ] amine.

Clause 16 the lubricant composition of any of clauses 1-13, wherein the triazole corrosion inhibitor comprises or consists of a tolutriazole derivative.

Clause 17 the lubricant composition according to any of claims 1 to 13, wherein the triazole corrosion inhibitor comprises or consists of bis (2-ethylhexyl) - [ (1, 2, 4-triazol-1-yl) methyl ] amine.

Clause 18, the lubricant composition of any preceding clause, wherein the antioxidant comprises or consists of an aryl amine antioxidant.

Clause 19: the lubricant composition of any preceding clause, wherein the antioxidant comprises or consists of phenyl-alpha-naphthylamine (PANA).

Clause 20 the lubricant composition of any preceding clause, wherein the antioxidant comprises or consists of a hydrocarbyl-substituted diphenylamine.

Clause 21 is the lubricant composition of any of the preceding clauses, wherein the antioxidant is selected from the group consisting of octyldiphenylamine, dioctyldiphenylamine, dinonyldiphenylamine, or mixtures thereof.

Clause 22, wherein the lubricant composition comprises 0.5 to 5 weight percent of the dispersant, 0.01 to 0.11 weight percent of the triazole corrosion inhibitor, 0.05 to 2 weight percent of the phosphorus antiwear compound, 0.2 to 1.2 weight percent of the antioxidant, and 0.1 to 1.0 weight percent of the sulfur-free detergent.

Clause 23, wherein the lubricant composition comprises 1.0 to 3 weight percent of the dispersant, 0.01 to 0.11 weight percent of the triazole corrosion inhibitor, 0.05 to 1 weight percent of the phosphorus antiwear compound, or 0.2 to 1.0 weight percent of the antioxidant, and 0.2 to 0.8 weight percent of the sulfur-free detergent.

Clause 24, wherein the lubricant composition comprises 0.2 to 3 weight percent of the dispersant, 0.01 to 0.11 weight percent of the triazole corrosion inhibitor, 0.1 to 0.5 weight percent of the phosphorus antiwear compound, or 0.2 to 0.7 weight percent of the antioxidant, and/or 0.2 to 0.5 weight percent of the sulfur-free detergent.

Clause 25, wherein the lubricant composition comprises 1 to 2 weight percent of the dispersant, 0.01 to 0.11 weight percent of the triazole corrosion inhibitor, 1 to 2 weight percent of the phosphorus antiwear compound, 0.2 to 0.4 weight percent of the antioxidant, and 0.2 to 0.5 weight percent of the sulfur-free detergent.

Clause 26 the lubricant composition of any of the preceding clauses, wherein the lubricant composition is substantially free of borate esters.

Clause 27 the lubricant composition of any of the preceding clauses, wherein the oil of lubricating viscosity is selected from the group consisting of an API group III base oil, a group IV base oil, or a mixture thereof.

Clause 28 the lubricant composition of any of the preceding clauses, wherein the lubricant composition has a viscosity of 1cSt to 32cSt at 100 ℃, as measured by ASTM D445.

Clause 29 the lubricant composition of any of the preceding clauses, wherein the lubricant composition has a viscosity of 1.5cSt to 15cSt, as measured by ASTM D445.

Clause 30 the lubricant composition of any of the preceding clauses, wherein the lubricant composition has a viscosity of 2cSt to 12cSt at 100 ℃, as measured by ASTM D445.

Clause 31 the lubricant composition of any of the preceding clauses, wherein the oil of lubricating viscosity comprises or consists of an API group III base oil.

Clause 32 the lubricant composition of any of the preceding clauses, wherein the oil of lubricating viscosity comprises or consists of an API group IV base oil.

Clause 33 the lubricating composition of any preceding clause, wherein the phosphorus antiwear agent is present in an amount sufficient to deliver 100 parts per million to 5000 parts per million of phosphorus to the composition.

Clause 34 is a method of lubricating an electric vehicle, the method comprising supplying a lubricant composition according to any of the preceding clauses to a drive train of the electric vehicle and operating the drive train.

Clause 35 a method of reducing wear in an electric vehicle by supplying the lubricant composition of any of clauses 1-33 to a driveline.

Clause 36 the use of the lubricating composition of any of clauses 1 to 33 to reduce wear in an electric vehicle driveline.

The use of the lubricating composition as set forth in any one of clauses 1 to 33 directly to reduce corrosion.

Examples

Lubricating compositions were prepared according to table 1 below.

TABLE 1 (wt% oil free-base oil added to 100%)

¹ Amine C9-diphenylamine

² C14 dialkylamides of alpha hydroxy acids

³ 1000Mn borated PIB succinimide (3.8% N,0.81% B)

⁴ 1550Mn non-borated PIB succinimide (1.41% N)

⁵ Polyalkylsiloxanes

⁶ Dibutyl phosphite

⁷ Condensation products of monomeric phosphorous acid or esters thereof with at least two alkylene glycols.

⁸ Amine salts of C14-C18 dialkylhydrogen phosphates and C12-C14 tertiary alkylamines

⁹ Bis (2-ethylhexyl) - [1,2, 4-triazol-1-yl) methyl ] amine

The FE8 roller bearing test is useful for assessing the effect of lubricants on the frictional behavior and wear of various bearings (including cylindrical roller thrust bearings) under conditions of use. To perform this test, two test cylindrical roller thrust bearings 81212 were installed in FE8 test equipment, subjected to axial bearing loads, run at a specific speed and maintained at the test temperature.

The lubricating compositions from table 1 were evaluated under the FE8 roller bearing test using equipment and test protocols according to DIN 51819T 1-T3. Tests were performed in duplicate to confirm the results. The test conditions are listed below and the results are summarized in table 2.

Conditions (conditions)

Test parameters

Axial load 800kN

Speed 7.5rpm

Fluid volume 4 liters

Temperature 80 ℃ (at the housing gasket)

Cage material brass

Oil flow 0.1/min (per bearing)

Test duration 2 runs x 80h

TABLE 2

Examples	1	3	6
				FE-8 bearing wear results
Wearing of components (mg)	52.0	-0.5	9.9
				Cage wear (mg)	106.7	12.0	47.8
Inner rail wear (mg)	95.6	0.2	20.9
				Outer rail wear (mg)	97.9	-0.3	17.2

In the wear test, the weight loss of the bearing component reflects the ability of the lubricant to protect the bearing. Formulations comprising salicylate detergents perform better than formulations comprising sulfonate detergents.

Copper corrosion testing was performed by the "ZF copper corrosion test" procedure, in which weighed copper coupons were placed in test oil and heated to 150 ℃ for 168 hours under an air purge of 83 mL/min. At the end of the test, the copper weight loss, copper% in the test emissions and visual rating (ASTM D-130) of the coupon were measured. The results are summarized in table 3.

TABLE 3 Table 3

Example 2, which contained a non-borated dispersant, exhibited higher copper weight loss at the end of the test than examples 4 and 5, which contained a non-borated dispersant and a calcium salicylate detergent, as shown by the amount of copper measured in the test fluid at the end of the test.

Each of the documents mentioned above is incorporated by reference herein, including any prior application requiring priority thereto, whether or not specifically listed above. The mention of any document is not an admission that the document is in accordance with the prior art or constitutes a general knowledge of any jurisdiction technician. Unless explicitly indicated otherwise or in the examples, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, etc. are to be understood as modified by the word "about". It is to be understood that the upper and lower limits of the amounts, ranges and proportions described herein may be independently combined. Similarly, the ranges and amounts for each element of the invention can be used with ranges or amounts for any other element.

As used herein, the transitional term "comprising" synonymous with "comprising," "containing," or "characterized by" is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. However, in each use of "comprising" herein, the term is intended to also encompass, as alternative embodiments, the phrases "consisting essentially of, and" consisting of, wherein "consisting of excludes any elements or steps not specified, and" consisting essentially of, allows for the inclusion of additional, unrecited elements or steps that do not materially affect the necessary or essential and novel characteristics of the composition or method under consideration.

As used herein, "substantially free" means that the amount of the substance under consideration is less than an amount that would affect the fluid-related properties in a measurable manner. "substantially free" may also mean that the substance in question is not intentionally added to the composition, but does not exclude the presence of such material as a contaminant. "substantially free" may also mean that the substance under consideration may be present in an amount below the detection limit of standard test methods now known to those skilled in the art or later developed. In some embodiments, "substantially free" may mean less than 10ppm by weight or even less than 5ppm by weight.

While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. In this regard, the scope of the invention is limited only by the following claims.

Claims

1. A lubricant composition comprising:

(a) An oil with lubricating viscosity;

(b) Dispersant;

(c) Triazole corrosion inhibitor;

(d) Phosphorus-containing anti-wear compounds;

(e) Antioxidants; and

(f) Sulfur-free detergents;

The lubricant composition contains no more than 40 ppm sulfur, or no more than 30 ppm sulfur, or no more than 20 ppm sulfur.

2. The lubricant composition according to claim 1, wherein the sulfur-free detergent comprises or is composed of a salicylate detergent.

3. The lubricant composition according to any of the preceding claims, wherein the sulfur-free detergent comprises or is composed of calcium salicylate.

4. The lubricant composition of claim 3, wherein the calcium salicylate detergent is present in an amount sufficient to deliver up to 2000 ppm, or 100 ppm to 1000 ppm, or 100 ppm to 600 ppm, or 100 ppm to 250 ppm, or 400 ppm to 750 ppm of calcium to the lubricant composition.

5. The lubricant composition according to any of the preceding claims, wherein the phosphorus anti-wear compound comprises a dialkyl phosphite.

6. The lubricant additive composition according to claim 5, wherein the dialkyl phosphite has the following formula:

R3 and R4 are independently alkyl groups having 1 to 24 carbon atoms.

7. The lubricant composition of claim 5, wherein the dialkyl phosphite comprises or is composed of dibutyl hydrogen phosphite.

8. The lubricant composition according to any one of claims 1 to 4, wherein the phosphorus-containing anti-wear compound comprises or is composed of phosphonates.

9. The lubricant composition according to claim 8, wherein the phosphonate comprises a reaction product of the following substances:

(a) Monomer phosphorous acid or its ester, and

(b) At least two alkylene glycols:

A first alkylene glycol (i) having two hydroxyl groups in a 1,4, 1,5, or 1,6 relationship;

The second alkylene glycol (ii) of alkyl-substituted 1,3-propanediol, wherein one or more alkyl substituents are located on one or more carbon atoms of the propylene unit, and the total number of carbon atoms in the alkyl-substituted 1,3-propanediol is about 5 to about 12.

The relative molar ratio of the monomeric phosphorous acid or its ester (a) to all alkylene glycols (b) is approximately 0.9:1.1 to approximately 1.1:0.9; and

The relative molar ratio of the first alkylene glycol (i) to the alkyl-substituted 1,3-propanediol (ii) is about 30:70 to about 65:35.

10. The lubricant composition according to any of the preceding claims, wherein the dispersant comprises or is composed of a succinimide dispersant.

11. The lubricant composition of claim 10, wherein the dispersant comprises or is composed of a succinimide dispersant having a number average molecular weight of 750 to 2200, or 750 to 1600, or 950 to 1550.

12. The lubricant composition according to any one of claims 1 to 9, wherein the dispersant comprises or is composed of an olefin polymer dispersant.

13. The lubricant composition of claim 12, wherein the dispersant comprises or is composed of an ethylene/propylene copolymer dispersant.

14. The lubricant composition according to any of the preceding claims, wherein the dispersant comprises a borate dispersant.

15. The lubricant composition according to any of the preceding claims, wherein the dispersant comprises a non-boronized dispersant.

16. The lubricant composition according to any of the preceding claims, wherein the triazole corrosion inhibitor comprises or is composed of 1,2,4-triazole.

17. The lubricant composition according to any of the preceding claims, wherein the triazole corrosion inhibitor comprises N,N-bis(2-ethylhexyl)-[(1,2,4-triazol-1-yl)methyl]amine or is composed of N,N-bis(2-ethylhexyl)-[(1,2,4-triazol-1-yl)methyl]amine.

18. The lubricant composition according to any one of claims 1 to 15, wherein the triazole corrosion inhibitor comprises or is composed of a toluenetriazole derivative.

19. The lubricant composition according to any one of claims 1 to 15, wherein the triazole corrosion inhibitor comprises or is composed of bis(2-ethylhexyl)-[(1,2,4-triazol-1-yl)methyl]amine.

20. The lubricant composition according to any of the preceding claims, wherein the antioxidant comprises or is composed of arylamine antioxidants.

21. The lubricant composition according to any of the preceding claims, wherein the antioxidant comprises or is composed of phenyl-α-naphthylamine (PANA).

22. The lubricant composition according to any of the preceding claims, wherein the antioxidant comprises or consists of a hydrocarbon-substituted diphenylamine.

23. The lubricant composition according to any of the preceding claims, wherein the antioxidant is selected from the group consisting of octyl diphenylamine, dioctyl diphenylamine, dinonyl diphenylamine, or mixtures thereof.

24. The lubricant composition according to any preceding claim, wherein the lubricant composition comprises:

The dispersant is present in amounts of 0.5% to 5% by weight, or 1.0% to 3% by weight, or 0.2% to 3% by weight, or 1% to 2% by weight.

0.01% to 0.11% by weight of the triazole corrosion inhibitor;

The phosphorus anti-wear compound in amounts of 0.05 wt% to 2 wt%, or 0.05 wt% to 1 wt%, or 0.1 wt% to 0.5 wt%, or 1.0 wt% to 2 wt%;

The antioxidant is present in amounts of 0.2 wt% to 1.2 wt%, or 0.2 wt% to 1.0 wt%, or 0.2 wt% to 0.7 wt%, or 0.2 wt% to 0.4 wt%.

The sulfur-free detergent is present in amounts of 0.1% to 1.0% by weight, or 0.2% to 0.8% by weight, or 0.2% to 0.5% by weight.

25. The lubricant composition according to any of the preceding claims, wherein the lubricant composition is substantially free of borate esters.

26. The lubricant composition according to any of the preceding claims, wherein the oil having a lubricating viscosity is selected from the group consisting of API Group III base oils, Group IV base oils, or mixtures thereof.

27. The lubricant composition according to any of the preceding claims, wherein the viscosity of the lubricant composition at 100°C is 1 cSt to 32 cSt, or 1.5 cSt to 15 cSt, or 2 cSt to 12 cSt, as measured by ASTM D445.

28. The lubricant composition according to any of the preceding claims, wherein the oil having a lubricating viscosity comprises or is composed of API Group III base oils.

29. The lubricant composition according to any of the preceding claims, wherein the oil having a lubricating viscosity comprises or is composed of API IV base oils.

30. The lubricating composition according to any of the preceding claims, wherein the phosphorus anti-wear agent is present in an amount sufficient to deliver 100 parts/million to 5000 parts/million of phosphorus to the composition.

31. A method of lubricating an electric vehicle, the method comprising supplying a lubricant composition according to any one of the preceding claims to the drivetrain of the electric vehicle and operating the drivetrain.

32. A method for reducing wear in an electric vehicle by supplying the drivetrain with a lubricant composition according to any one of claims 1 to 30.

33. Use of the lubricating composition according to any one of claims 1 to 30 for reducing wear in the powertrain of an electric vehicle.