WO2013062924A2

WO2013062924A2 - Lubricating composition containing an esterified polymer

Info

Publication number: WO2013062924A2
Application number: PCT/US2012/061404
Authority: WO
Inventors: William R.S. Barton; David Price; Marina Baum; Daniel C. Visger; Lynsey HICKMAN; Timothy R. Smith; Sona S. SLOCUM; Daniel J. Knapton
Original assignee: The Lubrizol Corporation
Priority date: 2011-10-27
Filing date: 2012-10-23
Publication date: 2013-05-02
Also published as: WO2013062924A3

Abstract

The invention provides a lubricating composition comprising an oil of lubricating viscosity and an esterified polymer. The invention further provides for the use of the esterified polymer as a viscosity modifier or dispersant viscosity modifier. The invention further provides a method for lubricating a mechanical device using the lubricating composition.

Description

TITLE

Lubricating Composition Containing an Esterified Polymer

FIELD OF INVENTION

[0001] The invention provides a lubricating composition comprising an oil of lubricating viscosity and an esterified polymer. The invention further provides for the use of the esterified polymer as a viscosity modifier or dispersant viscosity modifier. The invention further provides a method for lubricating a mechanical device using the lubricating composition.

BACKGROUND OF THE INVENTION

[0002] Viscosity index improvers are known to be added to lubricating oil compositions to improve the viscosity index of the lubricant. Typical viscosity index improvers include polymers of methacrylates, acrylates, olefins (such as copolymers of alpha-olefins and maleic anhydride and esterified derivatives thereof), or maleic-anhydride styrene copolymers, and esterified derivatives thereof. The viscosity index improvers tend to incorporate ester functional groups in pendant/ grafted/branched groups. The ester functional groups may be derived from linear alkyl alcohols with 1 to 40 carbon atoms. Recent attempts have been made to produce viscosity index improvers from copolymers of alpha- olefins.

[0003] US Patent 5,955,405 discloses a non-dispersant poly(meth)acrylate copolymer comprising units derived from: (A) from about 5 to about 15 weight percent butyl methacrylate; (B) from about 70 to about 90 weight percent of a C 10-C 15 alkyl (meth) acrylate; and (C) from about 5 to about 10 weight percent of a C 16-C30 alkyl (meth) acrylate.

[0004] US Patent 6,586,375 discloses a lubricating composition comprising an oil of lubricating viscosity and minor amount of a salt of at least one nitrogen containing polyacrylate and at least one phosphorus acid ester.

[0005] US Patent 6, 124,249 discloses a dispersant viscosity improving copolymer derived from (a) a nitrogen containing monomer; and (b) methacrylic acid esters containing from about 9 to about 25 carbon atoms in the ester group.

[0006] International Application WO 04/087850 discloses lubricating compositions containing block copolymers prepared from RAFT (Reversible Addition Fragmentation Transfer) or ATRP (Atom Transfer Radical Polymerisation) polymerisation processes. The polymers have frictional properties. The block copolymer may have di-block, tri-block, multi-block, comb and/or star architecture.

[0007] US Patent Application US05/038146 discloses star polymers derived from (i) a core portion comprising a polyvalent (meth) acrylic monomer, oligomer or polymer thereof or a polyvalent divinyl non-acrylic monomer, oligomer or polymer thereof; and (ii) at least two arms of polymerized alkyl (meth)acrylate ester. The polymers may be prepared by RAFT, ATRP or nitroxide mediated techniques.

[0008] International Application WO 96/23012 discloses star -branched polymers prepared from acrylic or methacrylic monomers. The polymers have a core or nucleus derived from acrylate or methacrylate esters of polyols. Further the polymers have molecular weights and other physical characteristics that make them useful for lubricating oil compositions. The star -branched polymers disclosed are prepared by anionic polymerisation techniques.

[0009] US Patent 5,070,131 disclose gear oil compositions having improved shear stability index essentially consisting of gear oil, a viscosity index improver comprising a hydrogenated star polymer comprising at least four arms, the arms comprising, before hydrogenation, polymerized conjugated diolefm monomer units and the arms having a number average molecular weight within the range of 3,000 to 15,000.

[0010] US Patent 7,254,249 discloses a lubricant additive based on a copolymer or a terpolymer made by free radical polymerisation of maleic anhydride or unsaturated carboxylic acids and an 1 -olefin and an oligo-olefin or polyisobutene. The copolymer is modified/ grafted with aliphatic and /or aromatic amines. The copolymer is suitable as soot and sludge dispersant.

[0011] US Patent 4,526,950 discloses copolymers of alpha-olefins having at least about 6 carbon atoms and unsaturated carboxylic acids or derivatives thereof, such as maleic anhydride, may be prepared by heating reactive amounts only of the monomers with a free radical initiator, in a solvent-free system and typically at a temperature of at least about 135 °C. There is no disclosure of the reduced specific viscosity of the copolymers. [0012] US Patent 6,419,714 discloses an aqueous hydrocarbon fuel composition containing a polyacidic polymer derived from C₄ to C30 olefin/maleic anhydride copolymers. There is no disclosure of the reduced specific viscosity of the copolymers.

[0013] International Application WO 07/133999 discloses a polymer with pendant groups may be a copolymer of an a-olefin and an unsaturated di-acid or an anhydride thereof. These polymer backbones are described as the same as those defined in US Patents 6,419,714 and US 4,526,950. The polymers of WO 07/133999 are useful in a lubricant to provide at least one of acceptable dispersancy properties, acceptable shear stability, acceptable viscosity index control and acceptable low temperature viscosity.

[0014] US Patent US 6,573,224 discloses compositions for two-cycle engines comprising an ester copolymer of an alpha-olefin and diester selected from a dialkyl fumarate and a dialkyl maleate, an aliphatic diester having exactly two ester groups and 20 to 40 carbon atoms.

[0015] US 6, 174,843 discloses an esterified alpha-olefin maleic anhydride copolymer wherein the number of repeating units ranges from about 20 to about 220, wherein the esterified alpha-olefin maleic anhydride copolymer is prepared by: (1) reacting maleic anhydride and a mixture of linear alpha-olefms of from about 10 to about 18 carbon atoms to form an alpha olefin-maleic anhydride copolymer having a molecular weight of from 18,000 to 40,000 and (2) reacting the alpha olefin-maleic anhydride copolymer with a mixture of C9- C i8 alcohols containing 47% C₁₂-C₁₆ alcohols, 20% C9-C10 alcohols and 33% C 16-C18 alcohols by weight. The copolymer is employed in a method for dispersing visible wax particles in a lubricating oil containing fractions of naphthenic or paraffinic crude oil at room temperature.

[0016] US Patent 6,746,993 discloses a viscosity index improver defined as a polymer with a solubility parameter of 8.6-9.4, a crystallisation temperature of -15°C, or less and a steric hindrance factor of 0 to 13. The polymer comprises alkyl alkenyl ethers and Ci_₄o alkyl methacrylates, of which some may be β-branched. The viscosity index improver is suitable for gear oils, hydraulic fluids, automatic transmissions and engine oils. [0017] US Patent 5,763,374 discloses lubricating oil compositions containing a copolymer composed of 20-70% of alkyl acrylates, 30-80% alkyl methacrylates. The lubricating oil may be a gear oil or an engine lubricant.

[0018] US Patent Application 2004/0077509 discloses a viscosity index improver polymer suitable for gear oils, transmissions, traction oils, hydraulic oil and engine oils. Further the polymer provides an improved shear stability and low temperature viscosity. The polymer is composed of (meth)acrylates derived from branched alcohols. The branched ester groups contain Cig_36 alkyl groups, with the proviso that the group does not contain a methylene group containing more than 16 carbon atoms. The polymer further contains 5-90% of either a C_8-17 alkyl (meth)acrylate or C 18-24 alkyl (meth)acrylate; and 5-50% of a hydroxy, or amide or carboxyl containing monomer. The monomer with branched ester groups may be present at 5 to 90%, or 10 to 70%) or 20 to 60%>. Further disclosed are lubricating compositions containing said polymer and a zinc or molybdenum anti-wear agent.

[0019] US Patent 4,822,508 discloses lubricating oils having high shear stability comprising paraffinic oils as their base and containing, as an additive improving the viscosity index, a mixture of at least two different polymer species, each of said polymer species being composed of monomers selected from the group consisting of (a) esters of methacrylic acid and acrylic acid with linear alcohols having 6 to 15 carbon atoms, (b) esters of methacrylic acid and acrylic acid with linear alcohols having from 16 to 30 carbon atoms, (c) esters of methacrylic acid and acrylic acid with branched alcohols having from 6 to 40 carbon atoms, (d) esters of methacrylic acid and acrylic acid with alcohols having from 1 to 5 carbon atoms, and (e) other monomers, different from (a)-(d), susceptible to free-radical copolymerization, and containing functional groups in the molecule, monomer or monomers (a); being from 0 to 100 mole percent of said polymer species, monomer(s) (b) being from 0 to 10 mole percent, monomers (c), (d) and (e) combined being from 0 to 100 mole percent, and monomers (a) to (e) combined being 100 mole percent of said polymer species, said individual polymer species differing from one another by at least 10 mole percent with respect to their content of component (a). SUMMARY OF THE INVENTION

[0020] The present invention provides a lubricating composition containing a polymer that is capable of providing at least one of acceptable viscosity index (VI), oil blend thickening capabilities (thickening efficiency), shear stability, good low temperature viscosity performance, acceptable dispersant viscosity modifier (DVM) performance, acceptable antioxidant performance, acceptable anti-wear performance, low viscosity modifier treatment level, acceptable film thickness (indicating acceptable friction control). Typically at least one of the performance benefits noted above is also observed whilst maintaining the appropriate lubricating performance for a mechanical device. DVMs may be employed to control viscosity over a wide temperature range and to control soot.

[0021] In one embodiment the invention provides a lubricating composition comprising an oil of lubricating viscosity and an esterified polymer, wherein the esterified polymer has at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms, and wherein ester groups are derived from a mixture of alcohols having 8 to 20 carbon atoms (i.e., 8, 10, 12, 14, 16, 18 or 20 carbon atoms). In one embodiment the mixture of alcohols is a C 12 and C14 mixture. In one embodiment the mixture of alcohols is a C12 and C16 mixture. In one embodiment the mixture of alcohols is a C 14 and C16 mixture. In one embodiment the mixture of alcohols is a C12, C14, C16 and C18 mixture. In one embodiment the mixture of alcohols is a C8, CIO, C12, C14, C16 and CI 8 mixture. It will be evident that, in accordance with accepted usage, the expression "ester groups having an even number of carbon atoms" refers to the number of carbon atoms in the alcohol-derived portion of the ester.

[0022] In one embodiment the esterified polymer has:

at least 60 mol % to 100 mol % of ester groups having an even number of carbon atoms; and

0 mol % to 40 mol % of ester groups having an odd number of carbon atoms.

[0023] In one embodiment the esterified polymer has:

at least 65 mol % to 100 mol % of ester groups having an even number of carbon atoms; and

0 mol % to 35 mol % of ester groups having an odd number of carbon atoms.

[0024] In one embodiment the esterified polymer has: at least 65 mol % to 95 mol % of ester groups having an even number of carbon atoms; and

5 mol % to 35 mol % of ester groups having an odd number of carbon atoms.

[0025] The ester groups may be linear or branched alkyl groups. In one embodiment the ester groups are a mixture of linear and branched alkyl groups.

[0026] In one embodiment the mixture of linear and branched alkyl groups may be substantially free of C 13 or CI 5 alkyl groups.

[0027] The mixture of linear and branched alkyl groups may be:

50 to 100 mol % linear, and 0 mol % to 50 mol % branched, or

75 mol % to 100 mol % linear and 0 mol % to 25 mol % branched, or 85 mol % to 100 mol % linear and 0 mol % to 15 mol % branched, or 95 mol % to 100 mol % linear and 0 mol % to 5 mol % branched.

[0028] In one embodiment the linear alcohol may have 12 carbon atoms.

[0029] The linear alcohol from which ester groups are derived may have a composition

55 mol % to 95 mol % C 12; and 5 mol % to 45 mol % C14, or

65 mol % to 85 mol % C 12; and 15 mol % to 35 mol % C 14.

[0030] The linear alcohol from which ester groups are derived may have a composition

0 mol % to 2 mol % C8;

0 mol % to 5 mol % C IO;

65 mol % to 85 mol % C 12;

15 mol % to 35 mol % C 14; and

0 mol % to 10 mol % C 16.

[0031] The linear alcohol from which ester groups are derived may have a composition

0.1 mol % to 1 mol % C8;

0.1 mol % to 3 mol % C IO;

65 mol % to 79.8 mol % C12;

15 mol % to 35 mol % C 14; and

1 mol % to 10 mol % C 16.

[0032] The branched alcohol may be branched at any point along the alcohol carbon chain. [0033] In one embodiment the invention provides a lubricating composition comprising an oil of lubricating viscosity, an esterified polymer of the invention, and further comprising a phosphorus-containing acid, salt, or ester; and dispersant.

[0034] In one embodiment the invention provides a method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a driveline device such as a gear, a gearbox or a transmission, and wherein the lubricating composition comprises: an oil of lubricating viscosity, an esterified polymer of the invention, and further comprising a phosphorus-containing acid, salt, or ester; and dispersant.

[0035] In one embodiment the invention provides a lubricating composition comprising an oil of lubricating viscosity, an esterified polymer of the invention, and further comprising a phosphorus-containing acid, salt, or ester; an extreme pressure agent, other than a phosphorus-containing acid, salt, or ester.

[0036] In one embodiment the invention provides a method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a driveline device such as a gear, a gearbox automatic transmission or a manual transmission, and wherein the lubricating composition comprises: an oil of lubricating viscosity, an esterified polymer of the invention, and further comprising a phosphorus-containing acid, salt, or ester; an extreme pressure agent, other than a phosphorus-containing acid, salt, or ester.

[0037] In one embodiment the invention provides a lubricating composition comprising an oil of lubricating viscosity, an esterified polymer of the invention, and further comprising anti-wear agent and a corrosion inhibitor.

[0038] In one embodiment the invention provides a method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a turbine system, a circulating oil system, or an industrial oil system, a driveline device such as a gear, a gearbox or a transmission, and wherein the lubricating composition comprises an oil of lubricating viscosity, an esterified polymer of the invention, an anti-wear agent and a corrosion inhibitor.

[0039] In one embodiment the invention provides a lubricating composition comprising an oil of lubricating viscosity, an esterified polymer of the invention, and further comprising an overbased detergent and a dispersant.

[0040] In one embodiment the invention provides a method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a turbine system, a circulating oil system, or an industrial oil system, a driveline device such as a gear, a gearbox or a transmission, and wherein the lubricating composition comprises: an oil of lubricating viscosity, an esterified polymer of the invention, an overbased detergent and a dispersant.

[0041] In one embodiment the invention provides for the use of the esterified polymer of the invention in a lubricating composition disclosed herein to provide at least one of acceptable viscosity index (VI), oil blend thickening capabilities (thickening efficiency), shear stability, good low temperature viscosity performance, acceptable dispersant viscosity modifier performance (DVM), acceptable antioxidant performance, acceptable anti-wear performance, low viscosity modifier treatment level, acceptable film thickness (indicating acceptable friction control).

[0042] In one embodiment the invention provides for the use of the esterified polymer of the invention in a lubricating composition disclosed herein in a mechanical device disclosed herein to provide at least one of acceptable viscosity index (VI), oil blend thickening capabilities (thickening efficiency), shear stability, good low temperature viscosity performance, acceptable dispersant viscosity modifier performance (DVM), acceptable antioxidant performance, acceptable anti-wear performance, low viscosity modifier treatment level, acceptable film thickness (indicating acceptable friction control).

[0043] In one embodiment the invention provides for the use of the esterified polymer of the invention in a lubricating composition disclosed herein in a mechanical device disclosed herein to provide thickening efficiency. DETAILED DESCRIPTION OF THE INVENTION

[0044] The present invention provides a lubricating composition and a method for lubricating a mechanical device as disclosed above. The present invention further provides for the use of the esterified polymer in a lubricating composition as is disclosed above.

[0045] As used herein "Shear Stability Index (SSI)" measures the ability of polymers used as V.I. improvers in lubricants to maintain thickening power during SSI is indicative of the resistance of a polymer to degradation under service conditions. The higher the SSI, the less stable the polymer, i.e., the more susceptible it is to degradation.

[0046] SSI is defined as the percentage of polymer-derived viscosity loss and is calculated as follows:

SSI = 100 x (kv fresh - kv after) /(kv fresh - kv oil) wherein "kv fresh" is the kinematic viscosity of the polymer-containing solution before degradation and "kv after" is the kinematic viscosity of the polymer-containing solution after degradation.

[0047] SSI is conventionally determined for a polymer in a lubricating

composition useful to provide a method of lubricating an internal combustion engine or hydraulic device to be based on ASTM D6278-98 (known as the Kurt-Orban (KO) or DIN bench test). The polymer under test is dissolved in suitable base oil (for example, solvent extracted 150 neutral) to a relative viscosity of 2 to 3 centistokes at 100° C. and the resulting fluid is pumped through the testing apparatus specified in the ASTM D6278-98 protocol.

[0048] In different embodiments the shear stability is such that the final lubricating composition (after testing in the Kurt-Orban) has a viscosity decrease of less than 30 %, or 20 % or less, or 15 % or less, or 10 % or less. Lubricating compositions that rely upon a shear stability based on Kurt-Orban test include non- driveline lubricants such as engine lubricants or hydraulic lubricants. Typically engine lubricants or hydraulic lubricants experience lower shear operating conditions and as a result less shear polymers may be used.

[0049] As used herein the SSI for a lubricating composition used in a method of lubricating a driveline device may be determined by a 20 hour KRL test (Volkswagon Tapered Bearing Roller Test). The test procedure is set out in both CEC-L-45-A-99 and DIN 51350-6-KRL/C. [0050] The polymer SSI for the K L test may be in the range of about 0 to about 100, or 0 to about 80, or about 0 to about 60, or about 0 to about 20, or about 0 to about 15, or about 0 to about 10, or about 0 to about 5. An example of a suitable range for the SSI includes about 1 to about 5.

[0051] The thickening efficiency is a measure of the thickening power of the polymer, and is defined by the equation below. The thickening efficiency is also described in US Patent 6, 1 10,880.

TE=(2/c) In ((kv of polymer+oil)/(kv of oil))/ln (2) wherein kv is the kinematic viscosity at 100 °C, c is the concentration in grams/100 grams of solution, and the log is consistently either natural or base 10.

[0052] The TE of a viscosity modifier depends somewhat on the particular base oil and other formulating components in the base oil, as well as the polymer concentration. For the purposes of this application, the oil is designated to be a solvent 100N, containing no components other than the esterified polymer of the present invention, with a polymer concentration sufficient to double the viscosity of the base oil at 100 °C.

Esterified Polymer

[0053] The esterified polymer is known to a person skilled in the art. Typically the esterified polymer is a polymer containing one or more carboxylic functional groups. The carboxylic functional group is typically formed from a reactive equivalent of a carboxylic acid functionality (e.g., anhydride or acid, acid chloride, or ester). The carboxylic functional group may be grafted onto the backbone, within the polymer backbone or as a terminal group on the polymer backbone. The esterified polymer may be a homopolymer or a copolymer.

[0054] The esterified polymer may be derived from a polymer with a backbone based on a polyisobutylene-succinic anhydride polymer, a maleic anhydride-styrene copolymer, an ester of a maleic anhydride-styrene copolymer, an alpha olefm-maleic anhydride copolymer, or a maleic anhydride graft copolymer of (i) a styrene-ethylene-alpha olefin polymer, (ii) a hydrogenated alkenyl aryl conjugated diene copolymer (that is, a hydrogenated alkenyl arene conjugated diene copolymer, in particular a hydrogenated copolymer of styrene- butadiene), (iii) a maleic anhydride- grafted polyolefin (in particular ethylene- propylene copolymer), or (iv) a hydrogenated isoprene polymer (in particular isobutylene-isoprene copolymer or a hydrogenated styrene-isoprene polymer), or mixtures thereof.

[0055] The polymer backbone for the polymer of the present invention may also be found in more detail in any number of publications. For example:

(i) esters of maleic anhydride and styrene-containing polymers are known from U.S. Patent 6,544,935;

(ii) grafted styrene-ethylene-alpha olefin polymers are taught in International publication WO 01/30947;

(iii) copolymers derived from isobutylene and isoprene have been used in preparing dispersants and are reported in International publication WO 01/98387;

(iv) grafted styrene-butadiene and styrene-isoprene copolymers are described in a number of references including DE 3, 106,959; and US Patents 5,512, 192, and 5,429,758;

(v) polyisobutylene succinic anhydrides have been described in numerous publications including US Patents 4,234,435; 3, 172,892; 3,215,707; 3,361,673; and 3,401,118;

(vi) maleic anhydride grafted ethylene-propylene copolymers have been described in US Patents 4,632,769; 4,517, 104; and 4,780,228; and

(vii) esters of (alpha-olefin maleic anhydride) copolymers have been described in US Patent 5,670,462.

[0056] Many of the polymer backbones are also described in "Chemistry and

Technology of Lubricants, Second Edition, Edited by R.M. Mortier and S. T.

Orszulik Published by Blackie Academic & Professional. In particular pages

144-180 discuss many of the polymer backbones (i)-(iv) and (vi)-(vi).

[0057] The esterified polymer of the invention may be a linear polymer or a star polymer. The esterified may be a homopolymer or a copolymer. The esterified polymer may have a random or a block architecture.

[0058] The esterified polymer may be prepared by any of the general processes described in the publications listed above. The esterified polymer of the present invention is prepared in the presence of an alcohol as defined by the ester group described above.

[0059] When the esterified polymer is a maleic anhydride grafted ethylene- propylene copolymer, the polymer may be a dispersant viscosity modifier capable of handling soot or sludge.

[0060] When the esterified polymer is a poly(meth)acrylate, the weight average molecular weight may range from 10,000 to 1 ,000,000, or 10,000 to 600,000, or 15,000 to 400,000. Typically, a linear poly(meth)acrylate may have a weight average molecular weight of 10,000 to 350,000. Typically, a star poly(meth)acrylate may have a weight average molecular weight of 250,000 to 1 ,000,000, or 250,000 to 600,000.

[0061] A measurement correlating with molecular weight of the copolymer (or interpolymer such as an alternating copolymer) may be expressed in terms of the "reduced specific viscosity" of the copolymer which is a recognised means of expressing the molecular size of a polymeric substance. Polymers that may have a RSV method used to characterize the polymer include esters of maleic anhydride and styrene-containing polymers, and esters of (alpha-olefin maleic anhydride) copolymers.

[0062] As used herein, the reduced specific viscosity (abbreviated as RSV) is the value typically obtained in accordance with the formula RSV = (Relative Viscosity - l)/Concentration, wherein the relative viscosity is determined by measuring, by means of a dilution viscometer, the viscosity of a solution of 1.6 g of the polymer in 100 cm³ of acetone and the viscosity of acetone at 30 °C. For purpose of computation by the above formula, the concentration is adjusted to 1.6 g of the copolymer per 100 cm of acetone. A more detailed discussion of the reduced specific viscosity, also known as the specific viscosity, as well as its relationship to the average molecular weight of a copolymer, appears in Paul J. Flory, Principles of Polymer Chemistry, (1953 Edition) pages 308 et seq.

[0063] The RSV may be 0.01 to 1.0, or 0.01 to 0.8, or 0.01 to 0.7, or 0.01 to 0.2, or 0.04 to 0.15. Typically, esterified polymers based on esters of maleic anhydride and styrene-containing polymers have higher RSV values than esterified polymers based on esters of (alpha-olefin maleic anhydride) copolymers. [0064] In one embodiment the esterified polymer may be further reacted with a dispersant monomer (typically nitrogen-containing monomer, or hydroxyl- containing monomer, or an alkoxylated monomer) to form a dispersant viscosity modifier.

[0065] Examples of a suitable hydro xyl- containing monomer or an alkoxylated monomer include 3-hydroxypropyl methacrylate, 3,4-dihydroxybutyl methacrylate, 2 -hydroxy ethyl methacrylate, 2-hydroxypropyl methacrylate, 2,5- dim ethyl- 1 ,6-hexanediol (meth)acrylate, 1 , 10-decanediol (meth)acrylate, carbonyl-containing methacrylates such as 2-carboxyethyl methacrylate, carboxymethyl methacrylate, oxazolidinylethyl methacrylate, N-(meth- acryloyloxy)formamide, acetonyl methacrylate, N-methacryloylmorpholine, N- methacryloyl-2-pyrrolidinone, N-(2-methacryloyloxyethyl)-2-pyrrolidinone, N- (3-methacryloyloxypropyl)-2-pyrrolidinone, N-(2-methacryloyloxypentadecyl)- 2-pyrrolidinone, N-(3-methacryloyloxyheptadecyl)-2-pyrrolidinone; glycol dimethacrylates such as 1 ,4-butanediol methacrylate, 2-butoxyethyl methacrylate, 2-ethoxyethoxymethyl methacrylate, 2-ethoxyethyl methacrylate; methacrylates of ether alcohols, such as tetrahydro fur fury 1 methacrylate, vinyloxyethoxyethyl methacrylate, methoxyethoxyethyl methacrylate, 1- butoxypropyl methacrylate, l -methyl-(2-vinyloxy)ethyl methacrylate, cyclo- hexyloxymethyl methacrylate, methoxymethoxyethyl methacrylate, benzyloxy- methyl methacrylate, furfuryl methacrylate, 2-butoxyethyl methacrylate, 2- ethoxyethoxymethyl methacrylate, 2-ethoxyethyl methacrylate, allyloxymethyl methacrylate, 1 -ethoxybutyl methacrylate, methoxymethyl methacrylate, 1 - ethoxyethyl methacrylate, ethoxymethyl methacrylate and ethoxylated (meth)acrylates which have typically from 1 to 20, or 2 to 8 ethoxy groups. The ethoxylated (meth)acrylates which can be used to prepare the can be obtained/obtainable, for example, by transesterification of alkyl (meth)acrylates with ethoxylated alcohols which typically have from 1 to 20, or 2 to 8 ethoxy groups. The hydrophobic radical of the ethoxylated alcohols may comprise from 1 to 40, or 4 to 22, carbon atoms, and either linear or branched alcohol radicals may be used. In one embodiment the ethoxylated (meth)acrylates have an -OH end group. [0066] Examples of commercially available ethoxylates which can be employed for the preparation of ethoxylated (meth)acrylates are ethers of the Lutensol® A brands, in particular Lutensol® A 3 N, Lutensol® A 4 N, Lutensol® A 7 N and Lutensol® A 8 N, ethers of the Lutensol® TO brands, in particular Lutensol® TO 2, Lutensol® TO 3, Lutensol® TO 5, Lutensol® TO 6, Lutensol® TO 65, Lutensol® TO 69, Lutensol® TO 7, Lutensol® TO 79, Lutensol® 8 and Lutensol® 89, ethers of the Lutensol® AO brands, in particular Lutensol® AO 3, Lutensol® AO 4, Lutensol® AO 5, Lutensol® AO 6, Lutensol® AO 7, Lutensol® AO 79, Lutensol® AO 8 and Lutensol® AO 89, ethers of the Lutensol® ON brands, in particular Lutensol® ON 30, Lutensol® ON 50, Lutensol® ON 60, Lutensol® ON 65, Lutensol® ON 66, Lutensol® ON 70, Lutensol® ON 79 and Lutensol® ON 80, ethers of the Lutensol® XL brands, in particular Lutensol® XL 300, Lutensol® XL 400, Lutensol® XL 500, Lutensol® XL 600, Lutensol® XL 700, Lutensol® XL 800, Lutensol® XL 900 and Lutensol® XL 1000, ethers of the Lutensol® AP brands, in particular Lutensol® AP 6, Lutensol® AP 7, Lutensol® AP 8, Lutensol® AP 9, Lutensol® AP 10, Lutensol® AP 14 and Lutensol® AP 20, ethers of the IMBENTIN® O brands, in particular of the IMBENTIN® AG brands, of the IMBENTIN® U brands, of the IMBENTIN® C brands, of the IMBENTIN® T brands, of the IMBENTIN(R) OA brands, of the IMBENTIN® POA brands, of the IMBENTIN® N brands and of the IMBENTIN® O brands and ethers of the Marlipal® brands, in particular Marlipal® 1/7, Marlipal® 1012/6, Marlipal® 1618/1 , Marlipal® 24/20, Marlipal® 24/30, Marlipal® 24/40, Marlipal® 013/20, Marlipal® 013/30, Marlipal® 013/40, Marlipal® 025/30, Marlipal® 025/70, Marlipal® 045/30, Marlipal® 045/40, Marlipal® 045/50, Marlipal® 045/70 and Marlipal® 045/80.

[0067] In one embodiment examples of a suitable hydroxyl-containing monomer, or an alkoxylated monomer include 2-hydroxyethyl methacrylate or ethoxylated methacrylate obtainable by transesterification of methyl methacrylate with an ethoxylate such as Marlipal™ 013/120 commercially available from Sasol.

[0068] Examples of a suitable nitrogen-containing monomer include Ν,Ν-dimethylacrylamide, N-vinyl carbonamides such as N-vinyl-formamide, vinyl pyridine, N-vinylacetamide, N-vinyl-propionamide, N-vinyl hydroxy- acetamide, N-vinyl imidazole, N-vinyl pyrrolidinone, N-vinyl caprolactam, dimethylaminoethyl acrylate (DMAEA), dimethyl amino ethyl methacrylate (DMAEMA), dimethylaminobutyl acrylamide, dimethylamino-propyl- methacrylate (DMAPMA), dimethylaminopropyl acrylamide, dimethyl- aminopropyl methacrylamide, dimethylaminoethyl acrylamide or mixtures thereof.

Polymer Composition

[0069] When the esterified polymer is a polymethacrylate, the polymer may be derived from a monomer composition comprising:

(a) a polymethacrylate having at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms;

(b) 0 wt % to 40 wt % (or 5 wt % to 35 wt %) of an alkyl methacrylate, wherein the alkyl group of the methacrylate has 1 to 9, or 1 to 4 carbon atoms (for example methyl, butyl, or 2-ethylhexyl); and

(c) 0 wt % to 10 wt % of a dispersant monomer (typically nitrogen- containing monomer, or hydroxyl-containing monomer, or an alkoxylated monomer).

[0070] When the esterified polymer is a polymethacrylate, the polymer may be derived from a monomer composition comprising:

(b) 0 wt % to 39.5 wt % (or 5 wt % to 34.5 wt %) of an alkyl methacrylate, wherein the alkyl group of the methacrylate has 1 to 9, or 1 to 4 carbon atoms (for example methyl, butyl, or 2-ethylhexyl); and

(c) 0.5 wt % to 5 wt % of a dispersant monomer (typically nitrogen-containing monomer, or hydroxyl-containing monomer, or an alkoxylated monomer).

Oils of Lubricating Viscosity

[0071] The lubricating composition comprises an oil of lubricating viscosity. Such oils include natural and synthetic oils, oil derived from hydro cracking, hydro gen ation, and hydrofinishing, unrefined, refined and re-refined oils and mixtures thereof.

[0072] Unrefined oils are those obtained directly from a natural or synthetic source generally without (or with little) further purification treatment.

[0073] Refined oils are similar to the unrefined oils except they have been further treated in one or more purification steps to improve one or more properties. Purification techniques are known in the art and include solvent extraction, secondary distillation, acid or base extraction, filtration, percolation and the like.

[0074] Re-refined oils are also known as reclaimed or reprocessed oils, and are obtained by processes similar to those used to obtain refined oils and often are additionally processed by techniques directed to removal of spent additives and oil breakdown products.

[0075] Natural oils useful in making the inventive lubricants include animal oils, vegetable oils (e.g., castor oil), mineral lubricating oils such as liquid petroleum oils and solvent-treated or acid-treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types and oils derived from coal or shale or mixtures thereof.

[0076] Synthetic lubricating oils are useful and include hydrocarbon oils such as polymerised and interpolymerised olefins (e.g., polybutylenes, poly- propylenes, propyl eneisobutylene copolymers); poly(l -hexenes), poly(l - octenes), poly(l-decenes), and mixtures thereof; alkyl-benzenes (e.g., dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)- benzenes); polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenyls); diphenyl alkanes, alkylated diphenyl alkanes, alkylated diphenyl ethers and alkylated diphenyl sulphides and the derivatives, analogs and homologs thereof or mixtures thereof.

[0077] Other synthetic lubricating oils include polyol esters (such as Priolube®3970), diesters, liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, and the diethyl ester of decane phosphonic acid), or polymeric tetrahydrofurans. Synthetic oils may be produced by Fischer-Tropsch reactions and typically may be hydroisomerised Fischer-Tropsch hydrocarbons or waxes. In one embodiment oils may be prepared by a Fischer-Tropsch gas-to-liquid synthetic procedure as well as other gas-to-liquid oils.

[0078] Oils of lubricating viscosity may also be defined as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five base oil groups are as follows: Group I (sulphur content >0.03 wt %, and/or <90 wt % saturates, viscosity index 80-120); Group II (sulphur content <0.03 wt %, and >90 wt % saturates, viscosity index 80-120); Group III (sulphur content <0.03 wt %, and >90 wt % saturates, viscosity index >120); Group IV (all polyalphaolefins (PAOs)); and Group V (all others not included in Groups I, II, III, or IV). The oil of lubricating viscosity comprises an API Group I, Group II, Group III, Group IV, Group V oil or mixtures thereof. Often the oil of lubricating viscosity is an API Group I, Group II, Group III, Group IV oil or mixtures thereof. Alternatively the oil of lubricating viscosity is often an API Group II, Group III or Group IV oil or mixtures thereof.

[0079] The amount of the oil of lubricating viscosity present is typically the balance remaining after subtracting from 100 wt % the sum of the amount of the additive as described herein above, and the other performance additives.

[0080] The lubricating composition may be in the form of a concentrate and/or a fully formulated lubricant. If the lubricating composition of the invention is in the form of a concentrate (which may be combined with additional oil to form, in whole or in part, a finished lubricant), the ratio of the of components of the invention to the oil of lubricating viscosity and/or to diluent oil include the ranges of 1 :99 to 99: 1 by weight, or 80:20 to 10:90 by weight. Other Performance Additives

[0081] The composition optionally comprises other performance additives. The other performance additives comprise at least one of metal deactivators, viscosity modifiers (other than the esterified polymer of the present invention as described above), detergents, friction modifiers, antiwear agents, corrosion inhibitors, dispersants, dispersant viscosity modifiers (other than the esterified polymer of the present invention as described above), extreme pressure agents, antioxidants, foam inhibitors, demulsifiers, pour point depressants, seal swelling agents and mixtures thereof. Typically, fully-formulated lubricating oil will contain one or more of these performance additives. [0082] In one embodiment the lubricating composition further includes other additives. In one embodiment the invention provides a lubricating composition further comprising at least one of a dispersant, an antiwear agent, a dispersant viscosity modifier, a friction modifier, a viscosity modifier (other than the esterified polymer of the present invention as described above), an antioxidant, an overbased detergent, or mixtures thereof.

[0083] In one embodiment the lubricating composition of the present invention further includes a dispersant. The dispersant of the present invention may be a succinimide dispersant, or mixtures thereof. In one embodiment the dispersant may be present as a single dispersant. In one embodiment the dispersant may be present in a mixture of two or three different dispersants, wherein at least one may be a succinimide dispersant.

[0084] The succinimide dispersant may be derived from an aliphatic polyamine, or mixtures thereof. The aliphatic polyamine may be aliphatic polyamine such as an ethylenepolyamine, a propylenepolyamine, a butylenepolyamine, or mixtures thereof. In one embodiment the aliphatic polyamine may be ethylenepolyamine. In one embodiment the aliphatic polyamine may be selected from the group consisting of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyamine still bottoms, and mixtures thereof.

[0085] The dispersant may be an N-substituted long chain alkenyl succinimide. Examples of N-substituted long chain alkenyl succinimides include polyisobutylene succinimide. Typically the polyisobutylene from which polyisobutylene succinic anhydride is derived has a number average molecular weight of 350 to 5000, or 550 to 3000 or 750 to 2500. Succinimide dispersants and their preparation are disclosed, for instance in US Patents 3, 172,892, 3,219,666, 3,316,177, 3,340,281, 3,351 ,552, 3,381 ,022, 3,433,744, 3,444,170, 3,467,668, 3,501 ,405, 3,542,680, 3,576,743, 3,632,51 1, 4,234,435, Re 26,433, and 6,165,235, 7,238,650 and EP Patent Application 0 355 895 A.

[0086] There are two commonly employed processes for making succinimide dispersants. These differ in the method by which a polyalkylene (typically polyisobutylene, but also copolymers including ethylene copolymer) substituent is prepared and by which it is affixed to a mono- or diacid or anhydride moiety, especially a succinic anhydride moiety or its reactive equivalent. In a conventional process (a), isobutylene is polymerized in the presence of AICI₃ to produce a mixture of polymers comprising predominantly trisubstituted olefin (III) and tetrasubstituted olefin (IV) end groups, with only a very small amount (for instance, less than 20 percent) of chains containing a terminal vinylidene group (I). In an alternative, "chlorine-free" or "thermal" process (b), isobutylene is polymerized in the presence of BF₃ catalyst to produce a mixture of polymers comprising predominantly (for instance, at least 70 percent) terminal vinylidene groups, with smaller amounts of tetrasubstituted end groups and other structures. These materials, sometimes referred to as "high vinylidene PIB," are also described in US Patent 6, 165,235, Table 1.

[0087] The conventional polyisobutylene of (a) reacts with maleic anhydride in the presence of chlorine by a series of chlorination, dehydrochlorination, and Diels-Alder reactions, more fully described in US Patent 6, 165,235, to provide a significant amount of di-succinated polymeric material.

[0088] In contrast, high vinylidene polyisobutylene of (b) is believed to react with maleic anhydride in the absence of chlorine by a series of thermal "ene" reactions to produce a mixture of mono- and di-succinated polymeric material.

[0089] Preparation of acylating agents from polyisobutylene made from a BF₃ process and their reaction with amines is disclosed in US Patent 4, 152,499. Similar adducts can be made using polymers other than polyisobutylene; for instance US Patent 5,275,747 discloses derivatized ethylene alpha-olefin polymers with terminal ethenylidene unsaturation which can be substituted with mono-or dicarboxylic acid producing moieties. These materials of component (b) may also contain a small amount of materials with cyclic structure. The cyclic components, however, are predominantly provided by materials from the chlorine route (process (a)) and the non-cyclic components are predominantly provided by materials from the thermal route (process (b)).

[0090] The two types of products, described above and also referred to as (a) and (b), are described in this text both in terms of their structure and in terms of their method of manufacture (chlorine versus non-chlorine or thermal process) for the purpose of completeness and clarity in description, and because it to be understood that further investigation may show that the structures depicted may prove to be incomplete or even to some extent incorrect. Nevertheless it is important to recognize that the materials prepared by the chlorine process are different from those prepared by the non-chlorine route, and these differences, whatever they may ultimately prove to be, may lead to performance characteristics. For example, it is also believed that the product from the chlorine reaction typically contains a certain percentage of internal succinic functionality, that is, along the backbone of the polymer chain, while such internal succinic functionality is believed to be substantially absent from the non-chlorine material. This difference may also play a role in performance. Applicants do not intend to be bound by any such theoretical explanation.

[0091] The hydrocarbyl substituents on each of the succinic anhydride components should normally be of sufficient length to provide a desired degree of solubility in a lubricating oil. Thus, while the length of the hydrocarbyl substituent in component (a) need not be the same as in component (b), each of

(a) and (b) will typically be derived from a hydrocarbylene having a number average molecular weight of at least 300, at least 800, or at least 1200, e.g., that of component (a) can be at least 1200. Typical upper limits to the molecular weight may be determined by considerations of solubility, cost, or other practical considerations, and may be up to 5000 or up to 2500. Thus, for instance, the hydrocarbylene from which the hydrocarbyl substituents of components (a) and

(b) are derived can independently have a number average molecular weight of 300 to 5000 or 800 to 2500.

[0092] Each of the two types of succinated polymeric materials can further react with an amine, an alcohol, or a hydroxyamine, and preferably a polyamine, to form a dispersant. Dispersants of this type generally are well known and are disclosed, for instance, in US Patent 4,235,435 (especially for type (a)) and in US Patent 5,719, 108 (especially for type (b)).

[0093] In one embodiment the dispersant may be prepared by process described in US 6,165,235. For example the dispersant may be prepared by reacting polyisobutylene succinic anhydride with an alkylene polyamine.

[0094] The alkylene polyamine may be an ethylene polyamine, propylene polyamine, butylene polyamine, or mixtures thereof. Typically the polyamine may be an ethylene polyamine, or mixtures thereof. Ethylene polyamines, such as some of those mentioned above, are preferred. They are described in detail under the heading "Diamines and Higher Amines" in Kirk Othmer's "Encyclopedia of Chemical Technology", 4th Edition, Vol. 8, pages 74-108, John Wiley and Sons, N.Y. (1993) and in Meinhardt, et al, U.S. Pat. No. 4,234,435.

[0095] Examples of ethylene polyamines include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylene- hexamine, N-(2-aminoethyl)-N'-[2-[(2-aminoethyl)amino] ethyl] -1 ,2-ethane- diamine, alkylene polyamine still bottoms, or mixtures thereof.

[0096] The alkylene polyamine bottoms may be characterized as having less than 2%, usually less than 1% (by weight) material boiling below about 200 °C. In the instance of ethylene polyamine bottoms, which are readily available and found to be quite useful, the bottoms contain less than about 2% (by weight) total diethylenetriamine (DETA) or triethylenetetramine (TETA). A typical sample of such ethylene polyamine bottoms obtained from the Dow Chemical Company of Freeport, Tex., designated "E-100" has a specific gravity at 15.6 °C of 1.0168, a percent nitrogen by weight of 33.15 and a viscosity at 40 °C of 121 cSt (mm /s). Gas chromatography analysis of such a sample showed it contains about 0.93% "Light Ends" (most probably diethylenetriamine), 0.72% triethylenetetramine, 21.74% tetraethylenepentamine and 76.61 % penta- ethylenehexamine and higher (by weight). A similar alkylene polyamine bottoms are commercially sold under as El 00™ polyethyleneamines from Dow Chemical.

[0097] The polyisobutylene succinic anhydride used in the preparation of the dispersant may be prepared by a method (as described in US 6,165,235) comprising:

(a) forming and heating at a temperature less than 150 °C a mixture comprising a polyisobutylene having number average molecular weight 300- 10,000 and 90 mole percent, based on the moles of said polyisobutylene, of tetra- and tri-substituted end groups, and a halogen, said halogen being added to said mixture in a molar amount up to an amount equal to said moles of end groups; (b) adding to said mixture an α,β-unsaturated acid (typically maleic acid) or an α,β-unsaturated anhydride (typically maleic anhydride) compound sequentially to or simultaneously with addition of said halogen;

(c) increasing the temperature of said mixture from 170 °C to 220 °C and holding the mixture at said temperature for a time sufficient to react said polyisobutylene with said α,β-unsaturated acid or said α,β-unsaturated anhydride compound;

(d) cooling said mixture to less than 200 °C and adding thereto equal molar amounts of said halogen and said α,β-unsaturated acid or said α,β- unsaturated anhydride compound; and

(e) increasing the temperature of said mixture to a limit of less than 220 °C and holding at said temperature for a time sufficient to reduce unreacted α,β- unsaturated acid or α,β-unsaturated anhydride compound in said mixture to less than three percent, wherein said method produces a polyisobutylene substituted carboxylic acylating agent having a chlorine content of less than 2,000 parts per million.

[0098] The dispersant of US 6,165,235 may be prepared by reacting the polyisobutylene prepared in Example 1 (see column 12, lines 25 to 63), or Example 2 (see column 12, line 64 to column 13, line 13) and an alkylene polyamine such as El 00™ polyethyleneamines. For instance the resultant compound may have a maleic anhydride derived units to polyisobutylene ratio of 1 : 1.3 to 1 : 1.8, such as 1 : 1.5. The compound may have a carbonyl to nitrogen ratio of 1 : 1 to 1 :5, or 1 : 1.3.

[0099] The dispersant may also be post-treated by conventional methods by a reaction with any of a variety of agents. Among these are boron compounds, urea, thiourea, dimercaptothiadiazoles, carbon disulphide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydride, nitriles, epoxides, and phosphorus compounds.

[00100] The dispersant may be present at 0.01 wt % to 20 wt %, or 0.1 wt % to 15 wt %, or 0.1 wt % to 10 wt %, or 1 wt % to 6 wt % of the lubricating composition.

[0100] The lubricating composition optionally further includes at least one antiwear agent. Examples of suitable antiwear agents include a phosphorus- containing acid, salt, or ester, titanium compounds, tartrates, tartrimides, oil soluble amine salts of phosphorus compounds, sulphurised olefins, metal dihydrocarbyldithiophosphates (such as zinc dialkyldithiophosphates), phosphites (such as dibutyl phosphite), phosphonates, thiocarbamate-containing compounds, such as thiocarbamate esters, thiocarbamate amides, thiocarbamic ethers, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamyl) disulp hides. The antiwear agent may in one embodiment include a tartrate, or tartrimide as disclosed in International Publication WO 2006/04441 1 or Canadian Patent CA 1 183 125. The tartrate or tartrimide may contain alkyl- ester groups, where the sum of carbon atoms on the alkyl groups is at least 8. The antiwear agent may in one embodiment include a citrate as is disclosed in US Patent Application 20050198894.

[0101] Another class of anti-wear additives includes oil-soluble titanium compounds as disclosed in US7727943 and US20060014651. The oil-soluble titanium compounds may function as antiwear agents, friction modifiers, antioxidants, deposit control additives, or more than one of these functions. In one embodiment the oil soluble titanium compound is a titanium (IV) alkoxide. The titanium alkoxide is formed from a monohydric alcohol, a polyol or mixtures thereof. The monohydric alkoxides may have 2 to 16, or 3 to 10 carbon atoms. In one embodiment, the titanium alkoxide is titanium (IV) isopropoxide. In one embodiment, the titanium alkoxide is titanium (IV) 2-ethylhexoxide. In one embodiment, the titanium compound comprises the alkoxide of a vicinal 1 ,2-diol or polyol. In one embodiment, the 1 ,2-vicinal diol comprises a fatty acid mono- ester of glycerol, often the fatty acid is oleic acid.

[0102] In one embodiment, the oil soluble titanium compound is a titanium carboxylate. In one embodiment the titanium (IV) carboxylate is titanium neodecanoate.

[0103] In one embodiment the oil soluble titanium compound may be present in the lubricating composition in an amount necessary to provide for 0 ppm to 1500 ppm titanium by weight, or 10 ppm to 1500 ppm titanium by weight, or 25 ppm to 150 ppm titanium by weight. [0104] The phosphorus-containing acid, salt or ester may be an antiwear agent and/or an extreme pressure agent. In one embodiment the phosphorus- containing acid, salt or ester is in the form of a mixture.

[0105] The phosphorus-containing acid, salt or ester may be ash-containing (i.e. metal containing) or ashless (i.e. metal free (prior to being mixed with other components)).

[0106] The phosphorus-containing acid, salt or ester includes (i) a non-ionic phosphorus compound; (ii) an amine salt of a phosphorus compound; (iii) an ammonium salt of a phosphorus compound; (iv) a monovalent metal salt of a phosphorus compound, such as a metal dialkyldithiophosphate or a metal dialkylphosphate; or (v) mixtures of (i), (ii), (iii) or (iv).

[0107] In one embodiment the phosphorus-containing acid, salt or ester comprises a metal dialkyldithiophosphate. The alkyl groups of the dialkyldithiophosphate may be linear or branched containing about 2 to about 20 carbon atoms, provided that the total number of carbons is sufficient to make the metal dialkyldithiophosphate oil soluble. The metal of the metal dialkyldithiophosphate typically includes monovalent or divalent metals. Examples of suitable metals include sodium, potassium, copper, calcium, magnesium, barium or zinc. In one embodiment the phosphorus-containing acid, salt or ester is a zinc dialkyldithiophosphate. Examples of a suitable zinc dialkylphosphate often referred to as ZDDP, ZDP or ZDTP) include zinc di-(2- methylpropyl amyl) dithiophosphate, zinc di-(2-ethylhexyl isopropyl) dithiophosphate, zinc di-(l ,3-dimethylbutyl isopropyl) dithiophosphate, zinc di- (1 ,3-dimethylbutyl) dithiophosphate, zinc di-(heptyl) dithiophosphate, zinc di- (octyl) dithiophosphate di-(2-ethylhexyl) dithiophosphate, zinc di-(nonyl) dithiophosphate, zinc di-(decyl) dithiophosphate, zinc di-(dodecyl) dithiophosphate, zinc di-(dodecylphenyl) dithiophosphate, zinc di-(heptylphenyl) dithiophosphate, or mixtures thereof.

[0108] In one embodiment the phosphorus-containing acid, salt or ester is other than metal dialkyldithiophosphate.

[0109] In one embodiment the phosphorus-containing acid, salt or ester comprises an ammonium or amine salt of a phosphorus-containing acid or ester. [0110] The amine salt of a phosphorus acid or ester includes 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 esters, ethers, and amides; and mixtures thereof.

[0111] The amine salt of a phosphorus acid or ester may be used alone or in combination. In one embodiment the amine salt of a phosphorus compound is derived from an amine salt of a phosphorus compound, or mixtures thereof.

[0112] In one embodiment the amine salt of a phosphorus acid or ester includes a partial amine salt-partial metal salt compounds or mixtures thereof. In one embodiment the amine salt of a phosphorus acid or ester further comprises a sulphur atom in the molecule.

[0113] The amines which may be suitable for use as the amine salt include primary amines, secondary amines, tertiary amines, and mixtures thereof. The amines include those with at least one hydrocarbyl group, or, in certain embodiments, two or three hydrocarbyl groups. The hydrocarbyl groups may contain about 2 to about 30 carbon atoms, or in other embodiments about 8 to about 26, or about 10 to about 20, or about 13 to about 19 carbon atoms.

[0114] Primary amines include ethylamine, propylamine, butylamine, 2-ethylhexylamine, octylamine, and dodecylamine, as well as such fatty amines as n-octylamine, n-decylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine, n-octadecylamine and oleylamine. Other useful fatty amines include commercially available fatty amines such as "Armeen®" amines (products available from Akzo Chemicals, Chicago, Illinois), such as Armeen C, Armeen O, Armeen OL, Armeen T, Armeen HT, Armeen S and Armeen SD, wherein the letter designation relates to the fatty group, such as coco, oleyl, tallow, or stearyl groups.

[0115] Examples of suitable secondary amines include dimethylamine, diethylamine, dipropylamine, dibutylamine, diamylamine, dihexylamine, diheptylamine, methylethylamine, ethylbutyl amine and ethyl amyl amine. The secondary amines may be cyclic amines such as piperidine, piperazine and morpholine.

[0116] The amine may also be a tertiary-aliphatic primary amine. The aliphatic group in this case may be an alkyl group containing about 2 to about 30, or about 6 to about 26, or about 8 to about 24 carbon atoms. Tertiary alkyl amines include monoamines such as tert-butylamine, tert-hexylamine, 1 -methyl - 1 -amino-cyclohexane, tert-octylamine, tert-decylamine, tert-dodecylamine, tert- tetradecylamine, tert-hexadecylamine, tert-octadecylamine, tert- tetracosanyl amine, and tert-octacosanyl amine.

[0117] In one embodiment the amine salt of a phosphorus acid or ester includes an amine with C l l to C 14 tertiary alkyl primary groups or mixtures thereof. In one embodiment the amine salt of a phosphorus compound includes an amine with C 14 to C 18 tertiary alkyl primary amines or mixtures thereof. In one embodiment the amine salt of a phosphorus compound includes an amine with CI 8 to C22 tertiary alkyl primary amines or mixtures thereof.

[0118] Mixtures of amines may also be used in the invention. In one embodiment a useful mixture of amines is "Primene® 81R" and "Primene® JMT." Primene® 81R and Primene® JMT (both produced and sold by Rohm & Haas) are mixtures of C l l to C14 tertiary alkyl primary amines and C 18 to C22 tertiary alkyl primary amines respectively.

[0119] In one embodiment the amine salt of a phosphorus acid or ester is the reaction product of a C14 to C 18 alkylated phosphoric acid with Primene 81R™ (produced and sold by Rohm & Haas) which is a mixture of C l l to C I 4 tertiary alkyl primary amines.

[0120] Examples of the amine salt of a phosphorus acid or ester include the reaction product(s) of isopropyl, methyl-amyl (4-methyl-2-pentyl or mixtures thereof), 2-ethylhexyl, heptyl, octyl or nonyl dithiophosphoric acids with ethylene diamine, morpholine, or Primene 81R™, and mixtures thereof.

[0121] In one embodiment a dithiophosphoric acid may be reacted with an epoxide or a glycol. This reaction product is further reacted with a phosphorus acid, anhydride, or lower ester (where "lower" signifies about 1 to about 8, or about 1 to about 6, or about 1 to about 4, or 1 to about 2 carbon atoms in the alcohol-derived portion of the ester). The epoxide includes an aliphatic epoxide or a styrene oxide. Examples of useful epoxides include ethylene oxide, propylene oxide, butene oxide, octene oxide, dodecene oxide, styrene oxide and the like. In one embodiment the epoxide is propylene oxide. The glycols may be aliphatic glycols having 1 to about 12, or about 2 to about 6, or about 2 to about 3 carbon atoms. The dithiophosphoric acids, glycols, epoxides, inorganic phosphorus reagents and methods of reacting the same are described in U.S. Patent numbers 3, 197,405 and 3,544,465. The resulting acids may then be salted with amines. An example of suitable dithiophosphoric acid is prepared by adding phosphorus pentoxide (about 64 grams) at about 58 °C over a period of about 45 minutes to about 514 grams of hydroxypropyl 0,0-di(4-methyl-2- pentyl)phosphorodithioate (prepared by reacting di(4-methyl-2-pentyl)- phosphorodithioic acid with about 1.3 moles of propylene oxide at about 25 °C). The mixture is heated at about 75 °C for about 2.5 hours, mixed with a diatomaceous earth and filtered at about 70 °C. The filtrate contains about 1 1.8% by weight phosphorus, about 15.2% by weight sulphur, and an acid number of 87 (bromophenol blue).

[0122] In one embodiment the phosphorus-containing acid, salt or ester comprises a non-ionic phosphorus compound. Typically the non-ionic phosphorus compound may have an oxidation of +3 or +5. The different embodiments comprise phosphite ester, phosphate esters, or mixtures thereof. A more detailed description of the non-ionic phosphorus compound include column 9, line 48 to column 1 1 , line 8 of US 6, 103,673.

[0123] The phosphorus-containing acid, salt or ester may be present in the lubricating composition at about 0.01 wt %> to about 20 wt %>, or about 0.05 wt %> to about 10 wt %>, or about 0.1 wt %> to about 5 wt %> of the lubricating composition. Typically the phosphorus-containing acid, salt or ester may be present in a lubricating composition for a driveline device.

[0124] In one embodiment the lubricating composition of the invention further comprises a dispersant viscosity modifier. The dispersant viscosity modifier may be present at 0 wt %> to 5 wt %>, or 0 wt %> to 4 wt %>, or 0.05 wt %> to 2 wt % of the lubricating composition.

[0125] The dispersant viscosity modifier may include functionalised polyolefins, for example, ethylene-propylene copolymers that have been functionalized with an acylating agent such as maleic anhydride and an amine; polymethacrylates functionalised with an amine, or styrene-maleic anhydride copolymers reacted with an amine. More detailed description of dispersant viscosity modifiers are disclosed in International Publication WO2006/015130 or U.S. Patents 4,863,623; 6, 107,257; 6,107,258; and 6,1 17,825. In one embodiment the dispersant viscosity modifier may include those described in US Patent 4,863,623 (see column 2, line 15 to column 3, line 52) or in International Publication WO2006/015130 (see page 2, paragraph [0008]).

[0126] The dispersant viscosity modifier of US Patent 4,863,623 may be described as being prepared by grafting of an olefmic carboxylic acid acylating agent onto a polymer of 15 to 80 mole percent of ethylene, from 20 to 85 mole percent of C₃_io alpha monoolefin, and from 0 to 15 mole percent of non- conjugated diene or triene, said polymer having an average molecular weight ranging from 5000 to 500,000, and further reacting said grafted polymer with an amine. The polymer is reacted with at least one olefmic carboxylic acid acylating agent to form one or more acylating reaction intermediates having a carboxylic acid acylating function and the additive is formed by reacting said reaction intermediate with an amine such as an amino -aromatic polyamine compound selected from an N-arylphenylenediamine, an aminothiazole, an aminocarbazole, an aminoindole, and aminopyrrole, an amino-indazolinone, an aminomercaptotriazole, and an aminopyrimidine.

[0127] The dispersant viscosity modifier of International Publication WO2006/015130 may be described as a reaction product of: (a) a polymer comprising carboxylic acid functionality or a reactive equivalent thereof, said polymer having a number average molecular weight of greater than 5,000; and (b) an amine component comprising at least one aromatic amine containing at least one amino group capable of condensing with said carboxylic acid functionality to provide a pendant group and at least one additional group comprising at least one nitrogen, oxygen, or sulfur atom, wherein said aromatic amine is selected from the group consisting of (i) a nitro- substituted aniline, (ii) amines comprising two aromatic moieties linked by a -C(0)NR- group, a -C(0)0- group, an -O- group, an -N=N- group, or an -S0₂- group where R is hydrogen or hydrocarbyl, one of said aromatic moieties bearing said condensable amino group, (iii) an aminoquinoline, (iv) an aminobenzimidazole, (v) an N,N- dialkylphenylenediamine, and (vi) a ring-substituted benzylamine. Typically the polymer of WO2006/015130 may be an ethylene-propylene copolymer or a copolymer of ethylene and a higher olefin, wherein the higher olefin is an alpha- olefin having 3 to 10 carbon atoms. The dispersant viscosity modifier of International Publication WO2006/015130 is prepared as disclosed in paragraphs [0065] to [0073] (these paragraphs relate to examples 1 to 9).

Extreme Pressure Agent

[0128] The extreme pressure agent may be other than a phosphorus-containing acid, salt, or ester.

[0129] The extreme pressure agent may include a boron-containing compound, a sulphur-containing compound, or mixtures thereof.

[0130] In one embodiment the extreme pressure agent comprises a boron- containing compound or mixtures thereof.

[0131] In one embodiment the extreme pressure agent comprises a sulphur- containing compound or mixtures thereof.

[0132] In one embodiment the extreme pressure agent comprises a sulphur- containing compound and a boron-containing compound.

[0133] The extreme pressure agent may be present in the lubricating composition at about 0.01 wt % to about 20 wt %, or about 0.05 wt % to about 10 wt %, or about 0.1 wt % to about 8 wt % of the lubricating composition.

Sulphur-Containing Compound

[0134] In one embodiment the extreme pressure agent is a sulphur-containing compound. In one embodiment the sulphur-containing compound is a sulphurised olefin, a polysulphide, or mixtures thereof.

[0135] Examples of the sulphurised olefin include an olefin derived from propylene, isobutylene, pentene, an organic sulphide and/or polysulphide including benzyldisulphide; bis-(chlorobenzyl) disulphide; dibutyl tetrasulphide; di-tertiary butyl polysulphide; and sulphurised methyl ester of oleic acid, a sulphurised alkylphenol, a sulphurised dipentene, a sulphurised terpene, a sulphurised Diels-Alder adduct, an alkyl sulphenyl N'N-dialkyl dithiocarbamates; or mixtures thereof. In one embodiment the sulphurised olefin includes an olefin derived from propylene, isobutylene, pentene or mixtures thereof.

[0136] In one embodiment the extreme pressure agent sulphur-containing compound comprising a dimercaptothiadiazole, or mixtures thereof. Examples of the dimercaptothiadiazole include 2,5-dimercapto-l ,3-4-thiadiazole or a hydrocarbyl-substituted 2,5-dimercapto-l,3,4-thiadiazole, or oligomers thereof. The oligomers of hydrocarbyl-substituted 2,5-dimercapto-l ,3,4-thiadiazole typically form by forming a sulphur-sulphur bond between 2,5-dimercapto-l,3-4- thiadiazole units to form oligomers of two or more of said thiadiazole units. Suitable 2,5-dimercapto-l ,3,4-thiadiazole compounds include 2,5-bis(tert- nonyldithio)- 1 ,3 ,4-thiadiazole or 2-tert-nonyldithio-5 -mercapto- 1 ,3 ,4-thiadiazole.

[0137] The number of carbon atoms on the hydrocarbyl substituents of the hydrocarbyl-substituted 2,5-dimercapto-l ,3-4-thiadiazole typically include about 1 to about 30, or about 2 to about 20, or about 3 to about 16.

Borate Ester or Borate Alcohol

[0138] In one embodiment the extreme pressure agent comprises a boron- containing compound. The boron- containing compound includes a borate ester, a borate alcohol, a borated dispersant or mixtures thereof.

[0139] In one embodiment the boron-containing compound is a borate ester or a borate alcohol. The borate ester or borate alcohol compounds are substantially the same except the borate alcohol has at least one hydroxyl group that is not esterified. Therefore, as used herein the term "borate ester" is used to refer to either borate ester or borate alcohol.

[0140] The borate ester may be prepared by the reaction of a boron compound and at least one compound selected from epoxy compounds, halohydrin compounds, epihalohydrin compounds, alcohols and mixtures thereof. The alcohols include dihydric alcohols, trihydric alcohols or higher alcohols, with the proviso for one embodiment that hydroxyl groups are on adjacent carbon atoms i.e. vicinal. Hereinafter "epoxy compounds" is used when referring to "at least one compound selected from epoxy compounds, halohydrin compounds, epihalohydrin compounds and mixtures thereof."

[0141] Boron compounds suitable for preparing the borate ester include the various forms selected from the group consisting of boric acid (including metaboric acid, HB0₂, orthoboric acid, H3BO3, and tetraboric acid, H₂B₄07), boric oxide, boron trioxide and alkyl borates. The borate ester may also be prepared from boron halides. [0142] In one embodiment the borate ester is formed by the reaction of a boron compound with an epoxy compound, dihydric alcohols, trihydric alcohols or higher alcohols.

[0143] The borate ester may be prepared by blending the boron compound and the epoxy compounds or alcohols described above and heating them at a suitable temperature, such as at about 80°C to about 250°C, about 90°C to about 240°C, or about 100°C to about 230°C, until the desired reaction has occurred. The molar ratio of the boron compounds to the epoxy compounds is typically about 4: 1 to about 1 :4, or about 1 : 1 to about 1 :3, or about 1 :2. An inert liquid may be used in performing the reaction. The liquid may be, for instance, toluene, xylene, chlorobenzene, dimethylformamide and mixtures thereof. Water is typically formed and is distilled off during the reaction. Alkaline reagents may be used to catalyze the reaction.

[0144] In one embodiment suitable borate ester compounds include tripropyl borate, tributyl borate, tripentyl borate, trihexyl borate, triheptyl borate, trioctyl borate, trinonyl borate and tridecyl borate. In one embodiment the borate ester compounds include tributyl borate, tri-2-ethylhexyl borate or mixtures thereof.

[0145] Antioxidants include sulphurised olefins, diarylamines or alkylated diarylamines, hindered phenols, molybdenum compounds (such as molybdenum dithiocarbamates), hydroxyl thioethers, or mixtures thereof. In one embodiment the lubricating composition includes an antioxidant, or mixtures thereof. The antioxidant may be present at 0 wt % to 15 wt %, or 0.1 wt % to 10 wt %, or 0.5 wt % to 5 wt %, or 0.5 wt % to 3 wt %, or 0.3 wt % to 1.5 wt % of the lubricating composition.

[0146] The diarylamine or alkylated diarylamine may be a phenyl-a- naphthylamine (PANA), an alkylated diphenylamine, or an alkylated phenylnapthylamine, or mixtures thereof. The alkylated diphenylamine may include di-nonylated diphenylamine, nonyl diphenylamine, octyl diphenylamine, di- octylated diphenylamine, di-decylated diphenylamine, decyl diphenylamine and mixtures thereof. In one embodiment the diphenylamine may include nonyl diphenylamine, dinonyl diphenylamine, octyl diphenylamine, dioctyl diphenylamine, or mixtures thereof. In one embodiment the diphenylamine may include nonyl diphenylamine, or dinonyl diphenylamine. The alkylated diarylamine may include octyl, di-octyl, nonyl, di-nonyl, decyl or di-decyl phenylnapthylamines .

[0147] The hindered phenol antioxidant often contains a secondary butyl and/or a tertiary butyl group as a sterically hindering group. The phenol group may be further substituted with a hydrocarbyl group (typically linear or branched alkyl) and/or a bridging group linking to a 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-butyl- phenol. In one embodiment the hindered phenol antioxidant may be an ester and may include, e.g., Irganox™ L-135 from Ciba. A more detailed description of suitable ester-containing hindered phenol antioxidant chemistry is found in US Patent 6,559, 105.

[0148] Examples of molybdenum dithio carbamates which may be used as an antioxidant include commercial materials sold under the trade names such as Vanlube 822™ and Molyvan™ A from R. T. Vanderbilt Co., Ltd., and Adeka Sakura-Lube™ S-100, S-165, S-600 and 525, or mixtures thereof.

[0149] Viscosity modifiers other than the polymer (a) of the invention, including hydrogenated copolymers of styrene-butadiene, ethylene-propylene copolymers, polyisobutenes, hydrogenated styrene-isoprene polymers, hydrogenated isoprene polymers, polymethacrylate acid esters, polyacrylate acid esters, poly(alkylstyrenes), alkenyl aryl conjugated diene copolymers, polyolefins, polyalkylmethacrylates and esters of maleic anhydride-styrene copolymers. Conventional poly(meth)acrylate polymers may be derived from monomers substantially the same as those defined for the polymeric arms. However, the conventional poly(meth)acrylate is generally free of a functional group selected from a halogen, an -0-N= group and an -S-C(=S)- group. In one embodiment the polymer of the invention is mixed with a conventional viscosity modifier.

[0150] Other performance additives such as corrosion inhibitors including octylamine octanoate, condensation products of dodecenyl succinic acid or anhydride and a fatty acid such as oleic acid with a polyamine. [0151] The corrosion inhibitor may also be described in paragraphs 5 to 8 of WO2006/047486, octylamine octanoate, condensation products of dodecenyl succinic acid or anhydride and a fatty acid such as oleic acid with a polyamine. In one embodiment the corrosion inhibitors include the Synalox® corrosion inhibitor. The Synalox® corrosion inhibitor may be a homopolymer or copolymer of propylene oxide. The Synalox® corrosion inhibitor is described in more detail in a product brochure with Form No. 118-01453-0702 AMS, published by The Dow Chemical Company. The product brochure is entitled "SYNALOX Lubricants, High-Performance Polyglycols for Demanding Applications."

[0152] Examples of another corrosion inhibitor include at least one of benzotriazoles, 1 ,2,4-triazoles, benzimidazoles, 2-alkyldithiobenzimidazoles, 2-alkyldithiobenzothiazoles, 2-(N,N-dialkyldithiocarbamoyl)benzothiazoles, 2,5- bis(alkyl-dithio)- 1 ,3 ,4-thiadiazoles, 2,5 -bis(N,N-dialkyldithiocarbamoyl)- 1 ,3 ,4- thiadiazoles, 2-alkyldithio-5-mercapto thiadiazoles or mixtures thereof. In one embodiment the corrosion inhibitor is benzotriazole. In one embodiment the corrosion inhibitor is a 2,5-bis(alkyl-dithio)-l ,3,4-thiadiazole. The corrosion inhibitor may be used alone or in combination with other corrosion inhibitors.

[0153] Benzotriazoles may contain hydrocarbyl substitutions on at least one of the following ring positions 1- or 2- or 4- or 5- or 6- or 7-. The hydrocarbyl groups may contain 1 to about 30, or 1 to about 15, or 1 to about 7 carbon atoms. In one embodiment the corrosion inhibitor is tolyltriazole. In one embodiment hydrocarbyl benzotriazoles substituted at positions 4- or 5- or 6- or 7- can be further reacted with an aldehyde and a secondary amine.

[0154] Examples of suitable hydrocarbyl benzotriazoles further reacted with an aldehyde and a secondary amine include N,N-bis(heptyl)-ar-methyl-lH- benzotriazole- 1 -methanamine, N,N-bis(nonyl)-ar-methyl- 1 H-benzotriazole- 1 - methanamine, N,N-bis(decyl)-ar-methyl-l H-benzotriazole- 1 -methanamine, N,N- bis(undecyl)-ar -m ethyl- 1 H-benzotriazole- 1 -methanamine, N,N-bis(dodecyl)-ar- methyl- 1 H-benzotriazole- 1 -methanamine N,N-bis(2-ethylhexyl)-ar -methyl- 1 H- benzotriazole-1 -methanamine and mixtures thereof. In one embodiment the corrosion inhibitor is N,N-bis(2-ethylhexyl)-ar-methyl-l H-benzotriazole- 1- methan amine. [0155] In one embodiment, the corrosion inhibitor is 2,5-bis(alkyl-dithio)- 1 ,3,4-thiadiazoles. The alkyl groups of 2,5-bis(alkyl-dithio)-l ,3,4-thiadiazoles contains 1 to about 30, or about 2 to about 25, or 4 to about 20, or about 6 to about 16 carbon atoms. Examples of suitable 2,5-bis(alkyl-dithio)-l ,3,4- thiadiazoles include 2,5-bis(tert-octyldithio)-l,3,4-thiadiazole, 2,5-bis(tert- nonyldithio)- 1 ,3 ,4-thiadiazole, 2,5 -bis(tert-decyldithio)- 1 ,3 ,4-thiadiazole, 2,5- bis(tert-undecyldithio)-l ,3,4-thiadiazole, 2,5-bis(tert-dodecyldithio)-l ,3,4- thiadiazole, or mixtures thereof.

[0156] The corrosion inhibitor may be present at about 0.0001 wt % to about 5 wt %, or about 0.0001 wt % to about 0.5 wt %, or about 0.0001 wt % to about 0.1 wt %, or about 0.0005 wt % to about 0.05 wt % of the lubricating composition.

[0157] Metal deactivators include derivatives of benzotriazoles (typically tolyltriazole), 1 ,2,4-triazoles, benzimidazoles, 2-alkyldithiobenzimidazoles or 2- alkyldithiobenzothiazoles; foam inhibitors including copolymers of ethyl acrylate and 2-ethylhexylacrylate and optionally vinyl acetate; demulsifiers including trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene oxides and (ethylene oxide-propylene oxide) polymers; pour point depressants including esters of maleic anhydride-styrene, polymethacrylates, polyacrylates or polyacrylamides; and seal swell agents including Exxon Necton- 37™ (FN 1380) and Exxon Mineral Seal Oil (FN 3200); and dispersant viscosity modifiers (often referred to as DVM) include functionalised polyolefins, for example, ethylene-propylene copolymers that have been functionalized with the reaction product of maleic anhydride and an amine, a polymethacrylate functionalised with an amine, or styrene-maleic anhydride copolymers reacted with an amine; may also be used in the composition of the invention.

Industrial Application

[0158] In one embodiment the method and lubricating composition of the invention may be suitable for a driveline device. The driveline device includes at least one of gear oils, axle oils, drive shaft oils, traction oils, manual transmission oils, automatic transmission oils, or off highway oils (such as a farm tractor oil). In one embodiment the invention provides a method of lubricating a manual transmission that may or may not contain a synchronizer system. In one embodiment the invention provides a method of lubricating an automatic transmission. In one embodiment the invention provides a method of lubricating an axle.

[0159] A lubricating composition for a driveline device may have a sulphur- content of greater than 0.05 wt %, or 0.4 wt % to 5 wt %, or 0.5 wt % to 3 wt %, 0.8 wt % to 2.5 wt %, 1 wt % to 2 wt %, 0.075 wt% to 0.5 wt %, or 0.1 wt% to 0.25 wt% of the lubricating composition.

[0160] A lubricating composition for a driveline device may have a phosphorus content of 100 ppm to 5000 ppm, or 200 ppm to 4750 ppm, 300 ppm to 4500 ppm, or 450 ppm to 4000 ppm.

[0161] An automatic transmission includes continuously variable transmissions (CVT), infinitely variable transmissions (IVT), toroidal transmissions, continuously slipping torque converter clutches (CSTCC), stepped automatic transmissions or dual clutch transmissions (DCT).

[0162] Automatic transmissions can contain continuously slipping torque converter clutches (CSTCC), wet start and shifting clutches and in some cases may also include metal or composite synchronizers.

[0163] Dual clutch transmissions or automatic transmissions may also incorporate electric motor units to provide a hybrid drive.

[0164] A manual transmission lubricant may be used in a manual gearbox which may be unsynchronized, or may contain a synchronizer mechanism. The gearbox may be self-contained, or may additionally contain any of a transfer gearbox, planetary gear system, differential, limited slip differential or torque vectoring device, which may be lubricated by a manual transmission fluid.

[0165] The gear oil or axle oil may be used in planetary hub reduction axles, mechanical steering and transfer gear boxes in utility vehicles, synchromesh gear boxes, power take-off gears, limited slip axles, and planetary hub reduction gear boxes.

[0166] In one embodiment mechanical device is driveline device. The polymer may be present in the lubricating composition at ranges a wide range of concentrations including 0.1 to 50 wt %, or 1 to 25 wt %, or 2 to 10 wt % of the lubricating composition. [0167] In one embodiment mechanical device is an internal combustion engine, or a hydraulic or a turbine, and the polymer defined by the invention may be present at 0.01 to 12 wt %, or 0.05 wt % to 10 wt %, or 0.075 to 8 wt % of the lubricating composition.

[0168] The mechanical device may be a hydraulic or a turbine.

[0169] In one embodiment the invention provides a method of lubricating an internal combustion engine. The engine components may have a surface of steel or aluminium.

[0170] An aluminium surface may be derived from an aluminium alloy that may be a eutectic or a hyper-eutectic aluminium alloy (such as those derived from aluminium silicates, aluminium oxides, or other ceramic materials). The aluminium surface may be present on a cylinder bore, cylinder block, piston or piston ring having an aluminium alloy, or aluminium composite.

[0171] The internal combustion engine may or may not have an Exhaust Gas Recirculation system. The internal combustion engine may be fitted with an emission control system or a turbocharger. Examples of the emission control system include diesel particulate filters (DPF), or systems employing selective catalytic reduction (SCR).

[0172] In one embodiment the internal combustion engine may be a diesel fuelled engine (typically a heavy duty diesel engine), a gasoline fuelled engine, a natural gas fuelled engine, a mixed gasoline/alcohol fuelled engine, or a hydrogen fuelled internal combustion engine. In one embodiment the internal combustion engine may be a diesel fuelled engine and in another embodiment a gasoline fuelled engine. In one embodiment the internal combustion engine may be a heavy duty diesel engine.

[0173] The internal combustion engine may be a 2-stroke or 4-stroke engine. Suitable internal combustion engines include marine diesel engines, aviation piston engines, low-load diesel engines, and automobile and truck engines. The marine diesel engine may be lubricated with a marine diesel cylinder lubricant (typically in a 2-stroke engine), a system oil (typically in a 2-stroke engine), or a crankcase lubricant (typically in a 4-stroke engine).

[0174] The lubricant composition for an internal combustion engine may be suitable for any engine lubricant irrespective of the sulphur, phosphorus or sulphated ash (ASTM D-874) content. The sulphur content of the engine oil lubricant may be 1 wt % or less, or 0.8 wt % or less, or 0.5 wt % or less, or 0.3 wt % or less. In one embodiment the sulphur content may be in the range of 0.001 wt % to 0.5 wt %, or 0.01 wt % to 0.3 wt %. The phosphorus content may be 0.2 wt % or less, or 0.12 wt % or less, or 0.1 wt % or less, or 0.085 wt % or less, or 0.08 wt % or less, or even 0.06 wt % or less, 0.055 wt % or less, or 0.05 wt % or less. In one embodiment the phosphorus content may be 0.04 wt % to 0.12 wt %. In one embodiment the phosphorus content may be 100 ppm to 1000 ppm, or 200 ppm to 600 ppm. The total sulphated ash content may be 0.3 wt % to 1.2 wt %, or 0.5 wt % to 1.1 wt % of the lubricating composition. In one embodiment the sulphated ash content may be 0.5 wt % to 1.1 wt % of the lubricating composition.

[0175] In one embodiment the lubricating composition may be an engine oil, wherein the lubricating composition may be characterised as having at least one of (i) a sulphur content of 0.5 wt % or less, (ii) a phosphorus content of 0.12 wt % or less, and (iii) a sulphated ash content of 0.5 wt % to 1.1 wt % of the lubricating composition.

[0176] An engine lubricating composition may further include other additives. In one embodiment the invention provides a lubricating composition further comprising at least one of a dispersant, an antiwear agent, a dispersant viscosity modifier (other than the compound of the invention), a friction modifier, a viscosity modifier, an antioxidant, an overbased detergent, or mixtures thereof. In one embodiment the invention provides a lubricating composition further comprising at least one of a polyisobutylene succinimide dispersant, an antiwear agent, a dispersant viscosity modifier, a friction modifier, a viscosity modifier (typically an olefin copolymer such as an ethylene-propylene copolymer), an antioxidant (including phenolic and aminic antioxidants), an overbased detergent (including overbased sulphonates and phenates), or mixtures thereof.

[0177] In one embodiment an engine lubricating composition may be a lubricating composition further comprising a molybdenum compound. The molybdenum compound may be an antiwear agent or an antioxidant. The molybdenum compound may be selected from the group consisting of molybdenum dialkyldithiophosphates, molybdenum dithiocarbamates, amine salts of molybdenum compounds, and mixtures thereof. The molybdenum compound may provide the lubricating composition with 0 to 1000 ppm, or 5 to 1000 ppm, or 10 to 750 ppm 5 ppm to 300 ppm, or 20 ppm to 250 ppm of molybdenum.

[0178] An engine lubricating composition may further include a phosphorus- containing antiwear agent. Typically the phosphorus-containing antiwear agent may be a zinc dialkyldithiophosphate, a phosphite, a phosphate, a phosphonate, and an ammonium phosphate salt, or mixtures thereof. In one embodiment the phosphorus-containing antiwear agent may be a zinc dialkyldithiophosphate, or mixtures thereof. Zinc dialkyldithiophosphates are known in the art. The antiwear agent may be present at 0 wt % to 3 wt %, or 0.1 wt % to 1.5 wt %, or 0.5 wt % to 0.9 wt % of the lubricating composition.

[0179] The overbased detergent may be present at 0 wt % to 15 wt %, or 0.1 wt % to 10 wt %, or 0.2 wt % to 8 wt %, or 0.2 wt % to 3 wt %. For example in a heavy duty diesel engine the detergent may be present at 2 wt % to 3 wt % of the lubricating composition. For a passenger car engine the detergent may be present at 0.2 wt % to 1 wt % of the lubricating composition. In one embodiment, an engine lubricating composition further comprises at least one overbased detergent with a metal ratio of at least 3, or at least 8, or at least 15.

[0180] The lubricating composition of the present invention may also be a grease. A grease composition will further comprise a thickening agent.

[0181] In one embodiment the grease thickener may be polyurea or diurea. The grease thickener may be lithium soap or lithium complex thickener.

[0182] When the lubricating composition is in the form of a grease, the amount of grease thickener present in the invention includes those in the range from 0.1 wt % to 40 wt %, or 1 wt % to 20 wt % of the grease composition.

[0183] The grease composition optionally further includes at least one antiwear agent (other than the compound of the invention). Examples of suitable antiwear agents include titanium compounds, tartrates, tartrimides, oil soluble amine salts of phosphorus compounds, sulphurised olefins, metal dihydrocarbyl- dithiophosphates (such as zinc dialkyldithiophosphates), phosphites (such as dibutyl or dioleyl phosphite), phosphonates, thiocarbamate-containing compounds, such as thiocarbamate esters, thiocarbamate amides, thiocarbamic ethers, alkylene-coupled thiocarbamates, bis(S-alkyldithiocarbamyl) disulphides, and oil soluble phosphorus amine salts. In one embodiment the grease composition may further include metal dihydrocarbyldithiophosphates (such as zinc dialkyldithiophosphates).

[0184] The grease composition may comprise:

(a) 0.01 wt % to 10 wt % of an esterified polymer of the present invention;

(b) 1 wt % to 20 wt % of a grease thickener;

(c) 0 wt % to 5 wt %, or 0.1 wt % to 5 wt % or 1 to 3 wt % of an oil soluble molybdenum complex;

(d) 0 wt % to 5 wt % of an extreme pressure agent;

(e) 0 wt % to 10 wt % of other performance additives; and

(f) balance of an oil of lubricating viscosity.

[0185] The mechanical device that may be lubricated with a grease may include a bearing, or a joint. The mechanical device bearing, or joint may be within an automotive power transmission, a driveline device, a vehicle suspension or steering system, or a hydraulic system. In one embodiment the mechanical device may be an automobile driving shaft. The mechanical device may contain a constant velocity joint.

[0186] The grease composition of the present invention may be useful for a constant velocity joint. Employing the grease composition to a constant velocity joint may reduce variation in rotational resistance or noise and vibration generation of the constant velocity joint. The grease composition may reduce variation in rotational resistance of a fixed type constant velocity joint used for an automobile driving shaft.

[0187] The grease may include a lithium soap grease made with a monocarboxylic acid (a simple soap grease), a lithium complex soap grease, a calcium soap grease or a calcium complex soap grease, or urea or urea complex grease.

[0188] The grease composition may also be useful for a low noise grease which are known and typically used in rolling element bearing applications such as pumps or compressors. [0189] The following examples provide illustrations of the invention. These examples are non-exhaustive and are not intended to limit the scope of the invention.

EXAMPLES

[0190] The C i2 -C₁₄ alkyl groups on the methacrylate examples described herein contain a mixture of C 12-alkyl groups (~70 mol %), and C 14-alkyl groups (~30 mol %). The alkyl groups may also contain trace amounts of other alkyl groups.

[0191] Preparative Example 1 : A container is charged with 35.1 parts methyl methacrylate, 136.5 parts C9 -C l l methacrylate, 7.8 parts butyl methacrylate, 136.5 parts C 12 -C14 methacrylate, 70.2 parts C 16 -C18 methacrylate and 130 parts of a hydrotreated naphthenic oil (Risella™ G 07, Shell Germany) followed by stirring for 0.25 hours. A solution of 1.36 parts of 2,2- azobismethylbutyronitrile (VAZO™-67, DuPont) in 2.7 parts toluene is added and stirred 0.1 hour. A reactor equipped with a stirrer, thermocouple reaching into the charged reaction mixture, N₂ inlet atop an addition funnel attached to a subsurface tube, and water condenser is charged with about 1/3 of the monomer- initiator solution. The remainder is placed in the addition funnel. With N₂ addition at 0.3 standard cubic feet per hour (SCFH) and stirring, the mixture is heated to 100 °C over 0.3 hour, heating is stopped and an exotherm to 131 °C over 0.1 hours is observed. The temperature begins to drop and after 2 minutes, at 131 °C dropwise addition of the remaining solution is begun. Addition time is 2 hours; 0.4 hours after the peak exothermic temperature, the temperature is 1 10 °C. The temperature during addition is maintained at 1 10 °C. The materials are cooled to 90 °C over 0.3 hour followed by addition of 0.25 part t-butyl peroctoate (Trigonox™ 21 , AKZO) followed by addition of 0.98 parts N- vinylimidazole (NVI), both all at once. While maintaining 90 °C, three additional increments, each of 0.98 parts NVI, are added at 0.25 hour intervals for a total of 4 additions. The mixture is held at 90 °C. for 1.25 hours after the final NVI addition. An additional 0.13 parts Trigonox 21 is added and the materials are held at 90 °C for an additional 1 hour. An additional 80 parts Risella G 07 oil is added, the materials are heated to 150 °C. and stripped at 40- 50 millimeters (mm) mercury for 1 hour, collecting 3 parts distillate. The residue is filtered employing a diatomaceous earth filter aid at 1 10 °C. The resulting product has Mn =58,400 and polydispersity (Mw /Mn)=2.90.

[0192] Preparative Example 2: Following essentially the procedure of Example 1 , a solution is prepared by mixing 27.5 parts methyl methacrylate, 5.5 parts butyl methacrylate, 105.5 part C9 -Cl l methacrylate, 105.5 parts C 12 -C14 methacrylate, 52.5 parts C 16 -C18 methacrylate and 80 parts Risella G 07 oil, then mixing in a solution of 1.2 parts VAZO-67 in 2.4 parts toluene. A reactor is charged with about 1/3 of this mixture and the remainder is added to an addition funnel. With stirring and N₂ addition at 0.3 SCFH the mixture is heated to 100 °C over 0.3 hours, heating is discontinued and the temperature rises exothermically to 139 °C over 2 minutes. After 2 minutes the temperature begins to drop; dropwise addition of the remaining monomer-initiator mixture is begun. The temperature is at 1 10 °C 0.3 hours after the peak exotherm. The balance of the mixture is added over 2 hours at 1 10 °C The materials are cooled to 90 °C and 0.2 part Trigonox 21 is added all at once. To this mixture are added 3.5 parts NVI at a dropwise rate over 1 hour, the materials are heated at 90 °C for 1 hour followed by addition of 0.1 part Trigonox 21. The materials are heated at 90 °C for 2 hours followed by addition of 0.1 parts Trigonox 21 followed by stirring at 90 °C for an additional 1.2 hours. To this mixture are added 81.5 parts Risella G 07 oil, the materials are heated with stirring to 150 °C and stripped to 40-50 mm Hg for 1 hour while 2 parts distillate are collected. The residue is filtered using a diatomaceous earth filter aid. The filtrate has Mn =52,800 and polydispersity=2.75.

[0193] Preparative Example 3 : A container is charged with 35.1 parts methyl methacrylate, 7.8 parts butyl methacrylate, 136.5 parts C9 -Cl l methacrylate, 136.5 parts C 12 -C14 methacrylate, 70.2 parts C16 -C18 methacrylate, 4.7 part NVI and 130 parts Risella G 07 oil. The materials are stirred for 0.25 hour, then a solution of 1.56 part VAZO-67 in 3.12 parts toluene is added followed by stirring for 0.1 hour. A reactor equipped as described in Example 1 is charged with about 1/3 of this solution; the remainder is placed in the addition funnel. With stirring and N₂ addition at 0.3 SCFH, the mixture is heated to 1 10 °C over 0.3 hour, heating is stopped and the temperature rises exothermically to 135 °C over 2 minutes. The temperature then begins to drop and after 2 minutes is at 133 °C. Dropwise addition of the remaining monomer-initiator mixture is begun and is continued for 2 hours. Temperature decreases to 1 10 °C after 0.3 hours and is held at 1 10 °C during addition. After addition is completed, the mixture is cooled to 90 °C over 0.3 hour followed by charging 0.25 part Trigonox 21. The materials are stirred at 90 °C for 2 hours, 0.26 part Trigonox 21 is charged and the materials are heated for an additional 2 hours. The materials are diluted with 80 parts additional Risella G 07 oil, heated with stirring to 150 °C, 40-50 mm Hg pressure, and stripped at 150 °C for 1 hour, collecting 1 part distillate. The residue is filtered at 1 10 °C with a diatomaceous earth filter aid.

[0194] Preparative Example 4: A mixture of methacrylate ester monomers as described in Example 2, 80 parts of 150 Neutral mineral oil and 2.3 parts VAZO- 67 in 15 parts butanol are combined to form a solution. Subsequent processing is substantially the same as described in Example 2 except the oil is 150 Neutral and the maximum exotherm is 136 °C.

[0195] Preparative Example 5 : A container is charged with 30.5 parts methyl methacrylate, 1 17 parts C9 -Cl l methacrylate, 6.1 parts butyl methacrylate, 1 17 parts C12 -C 14 methacrylate, 58.2 parts C16 -C18 methacrylate and 88.7 parts of a hydrotreated naphthenic oil (Hydrocal 38, Calumet Lubricants, Princeton, La., USA) followed by stirring for 0.25 hours. A solution of 1 part of 2,2- azobismethylbutyronitrile (VAZO-67, DuPont) in 5 parts toluene is added and stirred 0.1 hour. A reactor equipped with a stirrer, thermocouple reaching into the charged reaction mixture, N₂ inlet atop an addition funnel attached to a subsurface tube, and water condenser is charged with about 1/3 of the monomer- initiator solution. The remainder is placed in the addition funnel. With N₂ addition at 0.3 SCFH and stirring, the mixture is heated to 1 10 °C over 0.3 hour, heating is stopped and an exotherm to 138 °C over 0.1 hours is observed. The temperature begins to drop and after 3 minutes, at 136 °C dropwise addition of the remaining solution is begun. Addition time is 2 hours; 0.4 hours after the peak exothermic temperature, the temperature is 1 10 °C. The temperature during addition is maintained at 1 10 °C. The materials are cooled to 90 °C over 0.3 hour followed by addition of 0.2 part t-butyl peroctoate (Trigonox 21 , AKZO) followed by dropwise addition of 3.9 parts NVI over 1 hour at 90 °C. The reaction is held at 90 °C for 1 hour. While maintaining 90 °C, two additional increments of Trigonox 21 , each of 0.1 part, are added, the second addition 2 hours after the first. The mixture is held at 90 °C for 1 hour. An additional 90.4 parts Hydrocal 38 oil is added, the materials are heated to 150 °C and stripped at 30-50 millimeters mercury for 1 hour, collecting 6 parts distillate. The residue is filtered employing a diatomaceous earth filter aid at 1 10 °C. The resulting product has Mn =71 ,600 and polydispersity=2.61.

[0196] Preparative Example 6: A monomer-initiator solution is prepared as described in Example 1 except the oil is a 40 neutral naphthenic oil (Cross L-40, Cross Oil Co., Smackover Ark., USA) and reacted substantially as described in Example 1 ; maximum exotherm=138 °C. After cooling to 90 °C 0.25 part Trigonox 21 is added, stirred for 0.1 hour followed by dropwise addition of 7 parts NVI over 1 hour at 90 °C and heating for 1 additional hour. Trigonox 21 (0.13 part) is added, the materials are heated at 90 °C for 2 hours then additional 0.13 part Trigonox 21 is added. The reaction is continued for 1 hour, 80 parts Cross L-40 oil are added and the materials are stripped to 150 °C at 50 mm Hg for 1 hour removing 2 parts distillate. The materials are filtered yielding a filtrate containing a polymer having Mn =55,000 and polydispersity=2.72.

[0197] Preparative Example 7: The procedure of Example 6 is repeated except the oil is a hydrotreated naphthenic oil (Hydrocal™ 41 , Calumet Lubricants). The product has Mn =52,500 and polydispersity 2.73.

[0198] Preparative Example 8 : Following essentially the procedure of Example 1 , a solution is prepared by mixing 27.5 parts methyl methacrylate, 5.5 parts butyl methacrylate, 105.5 part C9 -Cl l methacrylate, 105.5 parts C 12 -C14 methacrylate, 52.5 parts C 16 -C18 methacrylate and 80 parts C 12 -16 alkylated aromatics (Huntsman Specialty Chemicals, Chocolate Bayou, Tex., USA), then mixing in a solution of 2.3 parts VAZO-67 in 10 parts toluene. A reactor is charged with about 1/3 of this mixture and the remainder is added to an addition funnel. With stirring and N₂ addition at 0.3 SCFH the mixture is heated to 1 10 °C over 0.3 hours, heating is discontinued and the temperature rises exothermically to 136 °C over 2 minutes. After 2 minutes the temperature begins to drop; at 134 °C dropwise addition of the remaining monomer-initiator mixture is begun. The temperature is at 1 10 °C 0.3 hours after the peak exotherm. The balance of the mixture is added over 2 hours at 1 10 °C. The materials are cooled to 90 °C and 0.2 part Trigonox 21 is added all at once. To this mixture are added 3.5 parts NVI at a dropwise rate over 1 hour, the materials are heated at 90 °C for 1 hour followed by addition of 0.1 part Trigonox 21. The materials are heated at 90 °C for 2 hours followed by addition of 0.2 parts Trigonox 21 followed by stirring at 90 °C for an additional 1.2 hours. To this mixture are added 120 parts C I 2- 16 alkylated aromatics, the materials are heated with stirring to 150 °C and stripped to 15 millimeters Hg for 1 hour while 24 parts distillate are collected. The residue is filtered using a diatomaceous earth filter aid. The filtrate contains a polymer having Mn =36,200 and polydispersity=2.62 by GPC.

[0199] Preparative Example 9: A methacrylate ester-oil solution as described in Example 1 is prepared followed by addition of 1.56 parts VAZO-67 in 3.1 parts toluene. Polymerization of the methacrylate monomers is conducted substantially as described in Example 1 ; peak exotherm=135 °C. After cooling to 90 °C, 0.25 part Trigonox 21 and 1.75 part NVI are added followed by addition, at 0.25 hour intervals, of 3 additional increments of 1.75 parts NVI for a total of 7 parts. The reaction is continued for 1.25 hours, 0.13 part Trigonox 21 is added, reaction is continued for an additional 2 hours then 0.13 part Trigonox 21 is added and heating is continued for 1 hour all heating at 90 °C. The materials are cooled, 80 parts Risella G-07 oil are added and the materials are stripped to 150 °C at 30-50 mm Hg for 1 hour collecting 1 part distillate followed by filtration through a diatomaceous earth filter aid at 1 10 °C. The filtrate contains a polymer having Mn =53,000 and polydispersity=2.77.

[0200] Preparative Example 10: A container is charged with 33.9 parts methyl methacrylate, 7.5 parts butyl methacrylate, 133.6 parts C9-C1 1 methacrylate, 133.6 parts C 12-C 14 methacrylate, 67.7 parts C 16-C18 methacrylate, 13.65 parts N-vinyl pyrrolidinone and 130 parts Risella G 07 oil. The materials are stirred for 0.25 hour, then a solution of 1.56 part VAZO-67 in 3.1 parts toluene is added followed by stirring for 0.1 hour. A reactor equipped as described in Example 1 is charged with about 1/3 of this solution; the remainder is placed in the addition funnel. With stirring and N₂ addition at 0.3 SCFH, the mixture is heated to 1 10 °C over 0.3 hour, heating is stopped and the temperature rises exothermically to 138 °C over 3 minutes. The temperature then begins to drop and after 2 minutes is at 136 °C. Dropwise addition of the remaining monomer-initiator mixture is begun and is continued for 2 hours. Temperature decreases to 1 10 °C after 0.3 hours and is held at 1 10 °C during addition. After addition is completed, the mixture is cooled to 90 °C over 0.3 hour followed by charging 0.25 part Trigonox 21. The materials are stirred at 90 °C for 2 hours, 0.26 part Trigonox 21 is charged and the materials are heated for an additional 2 hours. The materials are diluted with 80 parts additional Risella G 07 oil, heated with stirring to 150 °C, and stripped at 150 °C, 40-50 mm Hg pressure for 1 hour, collecting 1 part distillate. The residue is filtered at 1 10 °C with a diatomaceous earth filter aid. The filtrate contains a polymer having Mn =68,000 and Mw /Mn =2.91.

[0201] Preparative Example 1 1 : The procedure of Example 10 is repeated employing 34.3 parts methyl methacrylate, 7.6 parts butyl methacrylate, 137 parts C9-1 1 methacrylate, 135.3 parts C 16-18 methacrylate and replacing NVI with 8.73 parts N-vinyl formamide (NVF), other components remaining the same. The polymer product has Mn =58,500 and Mw /Mn =2.80.

[0202] Preparative Example 12: The procedure of Example 1 1 is repeated employing 34 parts methyl methacrylate, 7.5 parts butyl methacrylate, 133.9 parts each of C9-11 and C 12-14 methacrylates, 67.9 parts C 16- 18 methacrylate and replacing NVF with 12.9 parts 4-vinyl pyridine, other components remaining essentially the same. The polymer product has Mn =56,500 and Mw /Mn =2.64.

[0203] Preparative Example 13 : The procedure of Example 1 1 is substantially followed replacing NVF with 17.3 parts N-vinyl caprolactam. The product has Mn =72,800 and Mw /Mn =3.06.

[0204] Preparative Example 14: The procedure of Example 1 1 is substantially followed replacing NVF with 20.9 parts N,N-dimethylaminopropyl methacryl amide. The product has Mn =45,400 and Mw /Mn =2.64.

[0205] Preparative Example 15 : The procedure of Example 14 is followed employing 10.5 parts Ν,Ν-dimethylaminopropyl methacryl amide. The product has Mn =45,200 and Mw /Mn =2.66.

[0206] Preparative Example 16: A vessel is charged with 320 parts (1.18 equivalents) of a C 12-14 methacrylate, 80 parts (0.40 moles) 2-ethylhexyl methacrylate, 100 parts mineral oil (Total 85N), and 8.24 parts each of Trigonox- 21 (0.039 moles) and t-dodecanethiol (0.04 moles). The materials are mixed for 0.25 hour, then 1/3 of the mixture is charged to a reactor equipped with a stirrer, N₂ inlet with addition funnel, thermocouple and condenser, the remaining 2/3 being charged to the addition funnel. The reactor contents are heated to 105°C under N₂ at 8.5 1/hr over about 0.2 hour whereupon an exotherm to 137°C is observed and heating is discontinued. After about 1 minute, addition of the monomers from the addition funnel is begun at 4.4 ml/min. After about 0.3 hour the temperature is 90°C and heating is begun to maintain 89-90°C. Addition is completed after 1.5 hour, then heating is continued for 3.2 hours. At this time the infrared spectrum indicates the polymerization is completed. The batch is stripped to 150°C and 28 mm Hg, filtered through filter aid through a Buchner funnel with a cloth pad then refiltered through the same filter. The filtrate has Mw = 60,531 , Mn = 18,650 and PDI = 3.24.

[0207] Preparative Example 17: The procedure of Preparative Example 16 is followed employing 280 parts (1.03 equivalents) Ci₂_i₄ methacrylate, 120 parts (0.605 moles) 2-ethylhexyl methacrylate, 100 parts Total 85N, and 8.24 parts each of Trigonox-21 (0.039 moles) and t-dodecanethiol (0.04 moles). The peak temperature after exotherm is 141°C. Infrared spectrum shows polymerization is complete after 2.8 hours following completion of addition. The batch is stripped to 150°C at 16 mm Hg, The filtrate has Mw = 56,399, Mn = 19,495 and PDI = 2.89.

[0208] Preparative Example 18 : The procedure of Preparative Example 16 is followed employing 340 parts (1.25 equivalents) Ci₂_i₄ methacrylate, 60 parts (0.302 moles) 2-ethylhexyl methacrylate, 100 parts Total 85N, and 8.24 parts each of Trigonox-21 (0.039 moles) and t-dodecanethiol (0.04 moles). The peak temperature after exotherm is 135°C. Infrared spectrum shows polymerization is complete after 3.2 hours following completion of addition; reaction temperature 89-92°C. The batch is stripped to 150°C at 16 mm Hg. The filtrate has Mw = 57,872, Mn = 19,585 and PDI = 2.95.

[0209] Preparative Example 19: A vessel is charged with 280 parts (1.03 equivalents) Ci₂_i₄ methacrylate, 80 parts (0.4 moles) 2-ethylhexyl methacrylate, 40 parts (0.4 moles) methyl methacrylate, 100 parts Total 85N, and 8.24 parts each of Trigonox-21 (0.039 moles) and t-dodecanethiol (0.04 moles). The materials are mixed for 0.25 hour, then 1/3 of the mixture is charged to a reactor equipped with a stirrer, N₂ inlet with addition funnel, thermocouple and condenser, the remaining 2/3 being charged to the addition funnel. The reactor contents are heated to 105°C under N₂ at 8.5 1/hr over about 0.2 hour whereupon an exotherm to 147°C is observed and heating is discontinued. After about 1 minute, addition of the monomers from the addition funnel is begun at 4.4 ml/min. After about 0.3 hour the temperature is 90°C and heating is begun to maintain 89-92°C. Addition is completed after 1.5 hour, then heating is continued for 1.6 hours. At this time the infrared spectrum indicates the polymerization is completed. The batch is stripped to 150°C and 16 mm Hg, filtered through filter aid then refiltered through a Buchner funnel with a cloth pad. The filtrate has Mw = 58,897, Mn = 19,403 and PDI = 3.03.

[0210] Preparative Example 20: The procedure of Preparative Example 16 is followed employing 300 parts (1.1 1 equivalents) C 12-14 methacrylate, 100 parts (0.504 moles)2-ethylhexyl methacrylate, 100 parts Total 85N, and 8.24 parts each of Trigonox-21 (0.039 moles) and t-dodecanethiol (0.04 moles). The peak temperature after exotherm is 136°C. Infrared spectrum shows polymerization is complete after 2 hours following completion of addition; reaction temperature 89-91°C. The batch is stripped to 150°C at 14 mm Hg, The filtrate has Mw = 61 ,510, Mn = 20,622 and PDI = 2.98.

[0211] Preparative Example 21 : The procedure of Preparative Example 16 is followed employing 280 parts (1.03 equivalents) C 12-14 methacrylate, 120 parts (0.605 moles) 2-ethylhexyl methacrylate, 100 parts Total 85N, and 7.6 parts each of Trigonox-21 (0.035 moles) and t-dodecanethiol (0.038 moles). The peak temperature after exotherm is 145°C. Infrared spectrum shows polymerization is complete after 2 hours following completion of addition; reaction temperature 109-1 10°C. The batch is stripped to 150°C at 1 1 mm Hg, The filtrate has Mw = 52,263, Mn = 17,254 and PDI = 3.03.

[0212] Preparative Example 22: A vessel is charged with 3696 parts (13.64 equivalents) of C 12-14 methacrylate, 1584 parts (7.99 moles) (2-ethylhexyl methacrylate, 1320 parts mineral oil (Total 85N), and 100.3 parts each of Trigonox-21 (0.47 moles) and t-dodecanethiol (0.50 moles). The materials are mixed for 0.25 hour, then 1/3 of the mixture is charged to a reactor equipped with a stirrer, N₂ inlet with addition funnel, thermocouple and condenser, the remaining 2/3 being charged to the addition funnel. The reactor contents are heated to 1 10°C under N₂ at 9.9 1/hr over about 0.4 hour whereupon an exotherm to 152°C is observed and heating is discontinued. After about 1 minute temperature is 151°C, addition of the monomers from the addition funnel is begun at 60 ml/min. After about 0.5 hour the temperature is 1 10°C and heating is begun to maintain 108-1 13°C. Addition is completed after 1.6 hour, then heating is continued for 2 hours, whereupon the infrared spectrum shows polymerization is incomplete. An additional 2 parts Trigonox-21 are added, heating is continued for 2 hours, whereupon the infrared spectrum indicates the polymerization is completed. The batch is stripped to 150°C and 12 mm Hg, filtered through filter aid through a Buchner funnel with a cloth pad. The filtrate has Mw = 47,997, Mn = 16,728 and PDI = 2.87.

[0213] Preparative Example 23 : The procedure of Preparative Example 22 is followed except 90 parts each of Trigonox-21 (0.43 moles) and t-dodecanethiol (0.44 moles) are used. The exotherm is to 150°C, the reaction temperature is 109-1 16°C, 3 hours after addition of monomers is completed an additional 3 part Trigonox-21 are added whereupon after 0.5 hour additional heating the infrared spectrum indicates the polymerization is completed. The filtrate has Mw =51 ,200, Mn = 17,295 and PDI = 2.96.

[0214] Preparative Example 24: The procedure of Preparative Example 22 is followed except 79.2 parts each of Trigonox-21 (0.367 moles) and t- dodecanethiol (0.392 moles) are used. The exotherm is to 151°C, the reaction temperature is 108-1 13°C, 3.5 hours after addition of monomers is completed the infrared spectrum indicates the polymerization is completed. The filtrate has Mw = 56,044, Mn = 19,157 and PDI = 2.92.

[0215] Preparative Example 25 : The procedure of Preparative Example 24 is followed except 2.6 hours after the addition is completed, 2 parts additional Trigonox-21 are added, and after 2 more hours of heating, the infrared spectrum indicates the polymerization is completed. The filtrate has Mw =55,987, Mn = 18,635 and PDI = 3.00.

[0216] Preparative Example 26: A vessel is charged with 272.8 parts Ci₂_i4 methacrylate, 120 parts 2-ethylhexyl methacrylate, 100 parts mineral oil (Total 85N), and 7.6 parts each Trigonox 21 and t-dodecyl mercaptan. The materials are stirred for 0.25 hour, then about 1/3 of the mixture and 7.2 parts dimethylaminopropylmethacrylamide are charged to a reactor equipped with a stirrer, thermocouple, N₂ inlet with addition funnel and condenser. The remaining 2/3 of the mixture is placed in the addition funnel. The mixture in the flask is heated to 1 10°C under N₂, over 0.2 hour whereupon an exotherm ensues with an increase in temperature to 144°C. After about 0.1 hour the temperature is 140°C and addition of the mixture from the addition funnel is begun at 4.4 ml/hour. Within 0.2 hour the temperature is 1 10°C. The addition is continued for 1.5 hours, maintaining temperature at 107-1 14°C. Heating is continued for 3 hours at about 1 10°C, 0.4 part additional Trigonox 21 is added and after an additional 2.5 hours at about 1 10°C, the infrared spectrum indicated the reaction is completed. The batch is stripped to 150°C and 12 mm Hg, cooled to 85°C and filtered twice through a Buchner funnel employing filter aid. The filtrate has Mw = 50,018, Mn = 14,618 and PDI = 3.42.

[0217] Preparative Example 27: A vessel is charged with 272.8 parts Ci₂_i₄ methacrylate, 120 parts 2-ethylhexyl methacrylate, 100 parts mineral oil (Total 85N), and 5 parts each Trigonox 21 and t-dodecyl mercaptan. The materials are stirred for 0.25 hour, then about 1/3 of the mixture and 7.2 parts dimethylaminopropylmethacrylamide are charged to a reactor equipped with a stirrer, thermocouple, N₂ inlet with addition funnel and condenser. The remaining 2/3 of the mixture is placed in the addition funnel. The mixture in the flask is heated to 1 10°C under N₂, over 0.2 hour whereupon an exotherm ensues with an increase in temperature to 141 °C. After the exotherm subsides (1 minute) the temperature is 140°C, addition of remaining monomers is begun and is continued over 1.5 hours, temperature range is 108-1 12°C. After heating at 108-1 10°C for 3 hours, 0.5 part additional Trigonox 21 is added and heating at 1 10°C is continued for 2 hours, then materials are stripped to 135°C at 50 mm Hg. The residue is mixed with 37.6 parts additional oil. The product has Mw = 59,201 , Mn = 24,232 and PDI = 2.44.

[0218] Preparative Example 28 : The procedure of Preparative Example 22 is followed. The reaction after addition of all monomers is for 2.5 hours at which time infrared spectrum indicates reaction not quite completed. An additional 2.5 parts Trigonox 21 are added and after 2 hours at 1 10°C infrared shows reaction is complete. The filtrate has Mw = 46,271 , Mn = 14,689 and PDI = 3.15.

[0219] Preparative Example 29: The procedure of Example 28 is repeated except 1320 parts of Total 85N oil is replaced with a mixture of 1219.7 parts Total 85N and a 150N mineral oil. Mw = 41 ,490, Mn = 18,770 and PDI = 2.21.

[0220] Preparative Example 30: A vessel is charged with 3601 parts C_12-14 methacrylate, 1584 parts 2-ethylhexyl methacrylate, 1280 parts Total 85N, and 40 parts each 15 ON mineral oil, Trigonox 21 and t-dodecyl mercaptan. The materials are stirred for 0.25 hour, then about 1/3 of the mixture and 95 parts dimethylaminopropylmethacrylamide are charged to a reactor equipped with a stirrer, thermocouple, N₂ inlet with addition funnel and condenser. The remaining 2/3 of the mixture is placed in the addition funnel. The mixture in the flask is heated to 1 10°C under N₂, over 0.4 hour whereupon an exotherm ensues with an increase in temperature to 149°C. After the exotherm subsides (3 minutes) the temperature is 148 °C, addition of remaining monomers is begun and is continued over 1.6 hours, temperature is 1 10 °C 0.6 hour after peal exotherm and remaining addition is at 108-1 13°C. After heating at 108-110°C for 2.5 hours, infra-red spectrum indicates addition is not quite complete; 2.5 part additional Trigonox 21 is added and heating at 1 10°C is continued for 2 hours, with infra-red showing reaction is complete. Materials are stripped to 120°C at 50 mm Hg. The residue is mixed with 503 parts additional Total 85N. The product has Mw = 61 ,074, Mn = 27,521 and PDI = 2.22.

[0221] Preparative Example 31 : A vessel is charged with 3696 parts (13.64 equivalents) of Ci₂_i₄ methacrylate, 1584 parts (7.99 moles) (2-ethylhexyl methacrylate, 1281.5 parts Total 85N, 38.5 parts each 150N mineral oil, Trigonox-21 and t-dodecanethiol. The materials are mixed for 0.25 hour, then 1/3 of the mixture is charged to a reactor equipped with a stirrer, N₂ inlet with addition funnel, thermocouple and condenser, the remaining 2/3 being charged to the addition funnel. The reactor contents are heated to 1 10°C under N₂ over about 0.4 hour whereupon an exotherm to 150°C is observed and heating is discontinued. After about 2 minutes temperature is 149°C, addition of the monomers from the addition funnel is begun at 60 ml/min. After about 0.5 hour the temperature is 1 10°C and heating is begun to maintain 108-1 13°C. Addition is completed after 1.6 hour, then heating is continued for 2.5 hours, whereupon the infrared spectrum shows polymerization is incomplete. An additional 2.5 parts Trigonox-21 are added, heating is continued for 2 hours, whereupon the infrared spectrum indicates the polymerization is completed. The batch is mixed with 351.5 parts Total 85 then filtered through a Buchner funnel with a cloth pad. The filtrate has Mw =86,299, Mn = 36,473 and PDI = 2.37.

[0222] Preparative Example 32: A vessel is charged with 280 parts (1.02 equivalents) C_12-14 methacrylate, 120 parts (0.605 moles) 2-ethylhexyl methacrylate, 100 parts Total 85N, and 8.0 parts each of Trigonox-21 (0.039 moles) and t-dodecanethiol (0.04 moles). The materials are mixed for 0.25 hour, then 1/3 of the mixture is charged to a reactor equipped with a stirrer, N₂ inlet with addition funnel, thermocouple and condenser, the remaining 2/3 being charged to the addition funnel. The reactor contents are heated to 1 10°C under N₂ over about 0.2 hour whereupon an exotherm to 147°C is observed and heating is discontinued. After about 4 minutes, addition of the monomers from the addition funnel is begun at 4.4 ml/min. After about 0.3 hour the temperature is 1 10°C and heating is begun to maintain 106-1 1 1°C. Addition is completed after 1.5 hour, then heating is continued for 1.6 hours. An additional 0.8 part Trigonox 21 is added, heating is continued for 3 hours. At this time the infrared spectrum indicates the polymerization is completed. The batch is stripped to 150°C and 24 mm Hg. The residue is filtered through filter aid. The filtrate has Mw = 49,245, Mn = 15,903 and PDI = 3.10.

[0223] Preparative Example 33 : The procedure of Example 32 is substantially repeated. The maximum temperature after exotherm is 140°C, 0.6 part additional Trigonox 21 instead of 0.8 part is added and stripping is done to 150°C and 24 mm Hg. Filtrate has Mn = 53,931 , Mw = 17,335 and PDI = 3.1 1.

[0224] Preparative Examples 34 to 39 are the same as Additives A to as disclosed in US Patent 4,822,508, except a C 12-14 alcohol has been used in place of the C 12-15 mixture disclosed in each example.

[0225] Preparative Example 40: A styrene-maleic interpolymer is obtained by preparing a solution of styrene (536 parts) and maleic anhydride (505 parts) in toluene (7585 parts) and contacting the solution at a temperature of 99°-101° C. and an absolute pressure of 480-535 mm. Hg. with a catalyst solution prepared by dissolving 2.13 parts benzoyl peroxide in toluene (51.6 parts). The catalyst solution is added over a period of 1.5 hours with the temperature maintained at 99°-101° C. The mixture is maintained at 99°-101° C. and 480-535 mm Hg for 4 hours, then 2228 parts 40N naphthenic mineral oil (Cross L-40), is added to the mixture. The resulting product is a slurry of the interpolymer in the solvent mixture. The resulting interpolymer has a reduced specific viscosity of 0.42.

[0226] Preparative Example 41 : The product of Preparative Example 40 (101 parts), Neodol 91 (56 parts), a product of Shell Chemical Company identified as a mixture of C9, C 10 and Cn alcohols, TA-1618 (92 parts), a product of Proctor & Gamble identified as a mixture of C₁₆ and C₁₈ alcohols, C 12-14 alcohol mixture (62 parts), a product of Shell Chemical Company identified as a mixture of C 12, C n, C i4, and C₁₅ alcohols, and toluene and the contents are heated. Methane sulfonic acid (5 parts ) is added to the mixture. The mixture is heated under reflux conditions for 30 hours. The materials are vacuum stripped conditions for 30 hours. The materials are vacuum stripped.

[0227] Preparative Example 42: The product of Preparative Example 40 (202 parts), Neodol 91 (1 12 parts), TA 1618 (184 parts), C 12- 14 alcohol mixture (124 parts) and toluene (875 parts) are charged to a vessel. The mixture is then heated and stirred. Methanesulfonic acid (10 parts) is added to the mixture which is then heated under reflux conditions for 31 hours. The materials are vacuum stripped.

[0228] Preparative Example 43 : The product of Preparative Example 40 (101 parts), Alfol 810 (50 parts), a product of Vista Chemical identified as a mixture of Cg and C₁₀ alcohols, TA-1618 (92 parts), C I 2- 14 alcohol mixture (62 parts) and toluene (437 parts) are charged to a vessel. The mixture is heated and stirred. Methanesulfonic acid (5 parts) is added to the mixture which is heated under reflux conditions for 30 hours. The materials are vacuum stripped.

[0229] Preparative Example 44: Mix and heat 490 parts of maleic anhydride and 5000 parts of xylene to 100° C. Prepare an initiator solution by mixing 17 parts of 70% benzoyl peroxide with 500 parts of xylene. Add the initiator solution in one portion at 100° C. Apply a vacuum to effect reflux. At 100° C, add dropwise 520 parts of styrene over 20 minutes at a constant rate. The reaction is very exothermic. Maintain the reaction temperature at 100° C for 4 hours after the addition is completed. The interpolymer obtained should have an inherent viscosity of 0.15 dLg^"1.

[0230] Preparative Example 45 : Esterify 208 parts of the interpolymer of Preparative Example 44 by the same procedure as Preparative Example 43. Use 223 parts of C I 2- 14 alcohol mixture, 1 1 1 parts of Alfol 810, 222 parts of mineral oil, 4.22 parts of a 93% sulfuric acid solution, 41 parts of butanol, 15 parts of aminopropylmorpholine, 2.22 parts of di-tert-butyl phenol and 15 parts of diatomaceous earth.

[0231] Preparative Example 46: A styrene-maleic interpolymer is obtained by preparing a solution of styrene (536 parts) and maleic anhydride (505 parts) in toluene (7585 parts) and contacting the solution at a temperature of 99°-101° C and an absolute pressure of 480-535 mm Hg with a catalyst solution prepared by dissolving benzoyl peroxide (2.13 parts) in toluene (51.6 parts). The catalyst solution is added over a period of 1.5 hours with the temperature maintained at 99°-101° C. Mineral oil (2496 parts) is added to the mixture. The mixture is maintained at 99°-101° C and 480-535 mm Hg for 4 hours. The resulting product is a slurry of the interpolymer in the solvent mixture. The resulting interpolymer has a reduced specific viscosity of 0.42.

[0232] Preparative Example 47: The product of Preparative Example 46 (101 parts), Neodol 91 (56 parts), a product of Shell Chemical Company identified as a mixture of C9, C 10, and Cn alcohols, TA-1618 (92 parts), a product of Proctor & Gamble identified as a mixture of C₁₆ and C₁₈ alcohols, C 12-14 alcohol mixture (62 parts), a product of Shell Chemical Company identified as a mixture of C 12, Co, C i4, and C₁₅ alcohols, and toluene (437 parts) are charged to a vessel. The vessel is stirred and the contents are heated. Methane sulfonic acid (5 parts) is added to the mixture. The mixture is heated under reflux conditions for 30 hours. Aminopropyl morpholine (12.91 parts) is added to the mixture. The mixture is heated under reflux conditions for an additional 4 hours. Diatomaceous earth (30 parts) and a neutral paraffinic oil (302 parts) are added to the mixture which is then stripped. The residue is filtered to yield 497.4 parts of an orange-brown viscous liquid.

[0233] Preparative Example 48 : The product of Preparative Example 46 (202 parts), Neodol 91 (1 12 parts), TA 1618 (184 parts), C 12- 14 alcohol mixture (124 parts) and toluene (875 parts) are charged to a vessel. The mixture is heated and stirred. Methane sulfonic acid (10 parts) is added to the mixture which is then heated under reflux conditions for 31 hours. Aminopropyl morpholine (27.91 parts) is added to the mixture which is then heated under reflux conditions for an additional 5 hours. Diatomaceous earth (60 parts) is added to the mixture which is then stripped, 600 parts of polymer remaining in the vessel. A neutral paraffinic oil (600 parts) is added to the mixture which is then homogenized. The mixture is filtered through a heated funnel to yield 1063 parts of a clear orange-brown viscous liquid.

[0234] Preparative Example 49: The product of Preparative Example 46 (101 parts), Alfol 810 (50 parts), a product of Continental Oil Company identified as a mixture of C₈ and C₁₀ alcohols, TA-1618 (92 parts), C 12-14 alcohol mixture (62 parts) and toluene (437 parts) are charged to a vessel. The mixture is heated and stirred. Methane sulfonic acid (5 parts) is added to the mixture which is heated under reflux conditions for 30 hours. Aminopropyl morpholine (15.6 parts) is added to the mixture which is then heated under reflux conditions for an additional 5 hours. The mixture is stripped to yield 304 parts of a yellow-orange viscous liquid. Diatomaceous earth (30 parts) and a neutral paraffinic oil (304 parts) are added to the mixture which is then homogenized. The mixture is filtered through a heated funnel to yield 51 1 parts of a clear amber viscous liquid.

[0235] A series of polymethacrylate stars of different overall molecular weight are prepared by varying the amount of initiator and divinyl benzene (DVB) as shown in the Table 1 below. C_12-14 alkyl methacrylate (70% wt), 2- ethylhexyl methacrylate (30% wt), Trigonox™-21 (1 eq), cumyl dithiobenzoate (2 eq) and oil (26% wt) are combined at room temperature in a vessel equipped with a nitrogen inlet flowing at 28.3 L/hr, medium speed mechanical stirrer, a thermocouple and a water-cooled condenser and are stirred under N₂ blanket for 20 minutes to ensure mixing. The nitrogen flow is reduced to 14.2 L/hr and the mixture is set to be heated to 90 °C for 4 hrs. DVB is charged to the reaction flask and the mixture is stirred at 90 °C for a maximum of 12 hours. The results obtained for weight average molecular weight (Mw), number average molecular weight (Mn), the polydispersity, the number of arms on the star polymer and the percentage conversion to star polymer based on the amount of polymer arm converted to the star polymer are shown in Table 1 :

Table 1

Where * is the ratio of_DVB:polymer.

[0236] A series of polymethacrylate stars of different overall molecular weight are prepared by varying the amount of initiator and ethylene glycol dimethacrylate as shown in the Table 2 below. The mole % ratio of ethylene glycol dimethacrylate to polymer arms in resultant star polymer is 3 : 1 unless otherwise stated. Typically the polymers are prepared in 30 to 40 wt % of base/diluent oil.

Table 2

Footnote to Table 2

1 polymer prepared from 1 : 1 mole % ratio of ethylene glycol dimethacrylate to polymer arms in resultant star polymer;

2 polymer prepared from 4: 1 mole % ratio of ethylene glycol dimethacrylate to polymer arms in resultant star polymer;

3 polymer prepared from 7: 1 mole % ratio of ethylene glycol dimethacrylate to polymer arms in resultant star polymer;

A is C i2-i4 methacrylate;

B is methyl methacrylate;

C is dimethylaminopropyl methacrylamide;

D is dimethyl amino ethyl methacrylate;

[0237] A series of lubricating compositions 1 to 76 are prepared comprising a polymer of Preparative Example 1 to Example 76 respectively.

[0238] It is known that some of the materials described above may interact in the final formulation, so that the components of the final formulation may be different from those that are initially added. The products formed thereby, including the products formed upon employing lubricant composition of the present invention in its intended use, may not be susceptible of easy description. Nevertheless, all such modifications and reaction products are included within the scope of the present invention; the present invention encompasses lubricant composition prepared by admixing the components described above.

[0239] Each of the documents referred to above is incorporated herein by reference. Except in the Examples, or where otherwise explicitly indicated, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by the word "about." Unless otherwise indicated, each chemical or composition referred to herein should be interpreted as being a commercial grade material which may contain the isomers, by-products, derivatives, and other such materials which are normally understood to be present in the commercial grade. However, the amount of each chemical component is presented exclusive of any solvent or diluent oil, which may be customarily present in the commercial material, unless otherwise indicated. It is to be understood that the upper and lower amount, range, and ratio limits set forth herein may be independently combined. Similarly, the ranges and amounts for each element of the invention may be used together with ranges or amounts for any of the other elements.

[0240] As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include:

(i) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-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);

(ii) substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon nature of the substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulphoxy);

(iii) hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this invention, contain other than carbon in a ring or chain otherwise composed of carbon atoms; and

(iv) heteroatoms include sulphur, oxygen, nitrogen, and encompass substituents as pyridyl, furyl, thienyl and imidazolyl. In general, no more than two, preferably no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non-hydrocarbon substituents in the hydrocarbyl group.

[0241] While the invention has been explained in relation to its preferred embodiments, it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the specification. Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as fall within the scope of the appended claims.

Claims

3954-01 What is claimed is:

1. A lubricating composition comprising an oil of lubricating viscosity and an esterified polymer, wherein the esterified polymer has at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms, and wherein ester groups are derived from a mixture of alcohols having 8 to 20 carbon atoms (i.e., 8, 10, 12, 14, 16, 18 or 20 carbon atoms).

2. The lubricating composition of claim 1 , wherein the mixture of alcohols is a C 12 and C14 mixture, or a C12 and C16 mixture, or a C14 and C16 mixture, or a C12, C14, C16 and C18 mixture, or a C8, CIO, C12, C14, C16 and C18 mixture.

3. The lubricating composition of any preceding claim, wherein at least 60 mol % to 100 mol % of ester groups having an even number of carbon atoms; and

0 mol % to 40 mol % of ester groups having an odd number of carbon atoms.

4. The lubricating composition of any preceding claim, wherein at least 65 mol % to 100 mol % of ester groups having an even number of carbon atoms; and

0 mol % to 35 mol % of ester groups having an odd number of carbon atoms.

5. The lubricating composition of any preceding claim, wherein at least 65 mol % to 95 mol % of ester groups having an even number of carbon atoms; and

5 mol % to 35 mol % of ester groups having an odd number of carbon atoms.

6. The lubricating composition of any preceding claim, wherein the ester groups are linear or branched alkyl groups, or mixtures thereof.

7. The lubricating composition of any preceding claim, wherein the ester groups are a mixture of linear and branched alkyl groups.

8. The lubricating composition of claim 7, wherein the ester groups are a mixture of linear and branched alkyl groups comprising:

50 to 100 mol % linear, and 0 mol % to 50 mol % branched, or

9. The lubricating composition of any preceding claim, wherein ester groups are derived a linear alcohol with a composition comprising:

55 mol % to 95 mol % C 12; and 5 mol % to 45 mol % C14, or

65 mol % to 85 mol % C 12; and 15 mol % to 35 mol % C 14.

10. The lubricating composition of any preceding claim further comprising a phosphorus-containing acid, salt, or ester; and dispersant.

1 1. The lubricating composition of any preceding claim 1 to 9, further comprising a phosphorus-containing acid, salt, or ester; an extreme pressure agent, other than a phosphorus-containing acid, salt, or ester.

12. The lubricating composition of any preceding claim 1 to 9 further comprising anti-wear agent and a corrosion inhibitor.

13. The lubricating composition of any preceding claim 1 to 9 further comprising an overbased detergent and a dispersant.

14. A method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a driveline device such as a gear, a gearbox or a transmission, and wherein the lubricating composition comprises:

an oil of lubricating viscosity,

an esterified polymer wherein the esterified polymer has at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms, and wherein ester groups are derived from a mixture of alcohols having 8 to 20 carbon atoms (i.e., 8, 10, 12, 14, 16, 18 or 20 carbon atoms), and

a phosphorus-containing acid, salt, or ester; and dispersant.

15. A method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a driveline device such as a gear, a gearbox automatic transmission or a manual transmission, and wherein the lubricating composition comprises:

(a) an oil of lubricating viscosity,

(b) an esterified polymer wherein the esterified polymer has at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms, and wherein ester groups are derived from a mixture of alcohols having 8 to 20 carbon atoms (i.e., 8, 10, 12, 14, 16, 18 or 20 carbon atoms), and

(c) a phosphorus-containing acid, salt, or ester;

(d) an extreme pressure agent, other than a phosphorus-containing acid, salt, or ester.

16. A method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a turbine system, a circulating oil system, or an industrial oil system, a driveline device such as a gear, a gearbox or a transmission, and wherein the lubricating composition comprises

(a) an oil of lubricating viscosity,

(b) an esterified polymer wherein the esterified polymer has at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms, and wherein ester groups are derived from a mixture of alcohols having 8 to 20 carbon atoms (i.e., 8, 10, 12, 14, 16, 18 or 20 carbon atoms),

(c) an anti-wear agent, and

(d) a corrosion inhibitor.

17. A method for lubricating a mechanical device comprising a supplying to the mechanical device a lubricating composition, wherein the mechanical device comprises at least one of an internal combustion engine, a hydraulic system, a turbine system, a circulating oil system, or an industrial oil system, a driveline device such as a gear, a gearbox or a transmission, and wherein the lubricating composition comprises:

(a) an oil of lubricating viscosity,

(c) an overbased detergent and (d) a dispersant.

18. The method of any preceding claim 14 to 17, wherein the mechanical device is an internal combustion engine, or a hydraulic or a turbine, and the esterified polymer is present at 0.01 to 12 wt %, or 0.05 wt % to 10 wt %, or 0.075 to 8 wt % of the lubricating composition.

19. The method of any preceding claim 14 to 17, wherein the mechanical device is a driveline device the polymer is present at 0.1 to 50 wt %, or 1 to 25 wt %, or 2 to 10 wt % of the lubricating composition.

20. The use of an esterified polymer in a lubricating composition of any preceding claim 1 to 13 in a mechanical device to provide at least one of acceptable viscosity index (VI), oil blend thickening capabilities (thickening efficiency), shear stability, good low temperature viscosity performance, acceptable dispersant viscosity modifier performance (DVM), acceptable antioxidant performance, acceptable anti-wear performance, low viscosity modifier treatment level, acceptable film thickness (indicating acceptable friction control),

wherein the esterified polymer has at least 60 mol % to 100 mol % (or 65 mol % to 100 mol %, or 65 mol % to 95 mol %) of ester groups having an even number of carbon atoms, and wherein ester groups are derived from a mixture of alcohols having 8 to 20 carbon atoms (i.e., 8, 10, 12, 14, 16, 18 or 20 carbon atoms).

21. The use of an esterified polymer in a lubricating composition of any preceding claim 1 to 13 in a mechanical device disclosed herein to provide thickening efficiency,