KR20140125873A - Lubricating composition including esterified copolymer and low dispersant levels suitable for driveline applications - Google Patents

Abstract

Lubricating compositions, methods of manufacture and methods of use are disclosed. The lubricant includes an esterified copolymer comprising a unit derived from a vinyl aliphatic monomer and a unit derived from a carboxylic acid monomer, wherein the carboxylic acid monomer comprises a main chain containing an alpha, beta -ethylenically unsaturated dicarboxylic acid or a derivative thereof. The lubricating composition also includes oil of lubricating viscosity. The lubricating composition contains not more than 2.5 wt% of a dispersant other than the esterified copolymer in order to disperse the oxidation product.

Description

TECHNICAL FIELD [0001] The present invention relates to a lubricant composition containing an esterified copolymer and a low dispersant level suitable for use in a power transmission apparatus field. BACKGROUND OF THE INVENTION < RTI ID = 0.0 >

This aspect relates to a lubricating composition containing an esterified copolymer made from a vinyl aliphatic monomer and an alpha, beta-ethylenically unsaturated dicarboxylic acid or derivative thereof. The lubricating composition may further comprise an oil of lubricating viscosity. The copolymer acts as a dispersant for dispersing the oxidation product generated during the operation of the machine in the lubricating composition, eliminating the need for any other dispersant of the kind commonly used in powertrain applications. Lubricating compositions are applicable to vehicle powertrain systems such as automotive gear oils. The present invention also provides a method of using a lubricating composition to supply a lubricating composition to a powertrain component of a vehicle, such as a gearbox.

Lubricants for drive line powertrailers (e.g., gears or transmissions), especially automatic transmission fluids (ATF) and manual transmission fluids (MTFs) and axle fluids are challenging to meet lubricating requirements while providing durability and cleanliness .

Lubricants are typically prepared from polyalphaolefins or bright stocks (obtained from high viscosity lubricating oil, petroleum distillation residues). To impart desirable viscosity properties to the lubricant, a viscosity index improver, sometimes referred to as a viscosity modifier, was added to the lubricant composition to change the viscosity index. Typical conductivity index improvers for gear oils include oil soluble polyisobutylene, low molecular weight polymers of methacrylates and acrylates, olefin copolymers and polyalphaolefins such as PAO 100. If treated at high shear and high temperature, such lubricating oil may undergo oxidation. In particular, oxidation byproducts can be detrimental to powertrain components, especially if lubricants are ever replaced, even if they are likely to be replaced. Thus, a dispersant is often added to the lubricant. The dispersant attaches itself to the contaminant particles and leaves the particles in a suspended state to reduce deposition of the oxidation product. Typical dispersing agents include ashless dispersants such as N-substituted long chain alkenyl succinimides, polyisobutylene succinimides complexed with zinc, Mannich bases, and dispersants prepared by boronating these compounds .

International application WO 2007/133999 discloses polymers with pendent groups which can be copolymers of an alpha-olefin and an unsaturated diacid or an anhydride thereof. The polymer may contain an ester functional group at the side group. The ester functional groups may be derived from linear or branched alkyl alcohols. The polymers of WO 2007/133999 are said to be useful in providing at least one of an acceptable dispersive property, an acceptable shear stability, an acceptable viscosity index control and an acceptable low temperature viscosity in a lubricant.

Examples of other polymers are disclosed in U.S. Patent Nos. 5,435,928; 6,174,843; 6,419,714; 6,544,935; And 7,254,249; And International Application No. WO2010 / 014655.

U.S. Patent No. 5,188,745 discloses a process for the preparation of polyolefins by reacting ethylene with at least one C ₃ -C ₁₀ alpha -monoolefin, and optionally with a polyene selected from unconjugated dienes and trienes and reacting it with at least one olefinic carboxylic acid acylating agent, (2-aminoalkyl) imidazolidone to form at least one acylation reaction intermediate having a carboxylic acid acylation function in the structure, and reacting the reaction intermediate with N- (2-aminoalkyl) imidazolidone to form a graft- A lubricating oil composition comprising an additive composition containing a modified copolymer is disclosed.

Exemplary embodiments provide lubricant compositions with improved cleanliness and oxidation stability that can be achieved using only a small amount of dispersant, or in the absence of the dispersant, other than the esterified copolymer as disclosed herein.

According to one aspect of the exemplary embodiment, the lubricating composition includes a main chain containing a unit derived from a vinyl aliphatic monomer and a unit derived from a carboxylic acid monomer, wherein the carboxylic acid monomer contains an alpha, beta -ethylenically unsaturated dicarboxylic acid or a derivative thereof ≪ / RTI > In addition, the lubricating composition also includes oil of lubricating viscosity. The lubricating composition contains not more than 2.5 wt% of a dispersant other than the esterified copolymer in order to disperse the oxidized product.

In another aspect, a method for producing a lubricating composition comprises the steps of (1) reacting (i) a vinyl aliphatic monomer and (ii) a carboxylic acid monomer containing an alpha, beta -ethylenically unsaturated dicarboxylic acid or a derivative thereof to form a carboxylic acid monomer (2) optionally esterifying the copolymer of step (1) to form an esterified copolymer, and (3) optionally repeating steps (a) and Comprising reacting a copolymer of formula (1) or (2) with a nitrogen-containing compound in an amount to provide an esterified copolymer having at least 0.01 wt% nitrogen, wherein the final copolymer comprises (1), ) And (3), and reacting the thus-formed esterified copolymer with an oil of lubricating viscosity and an esterified copolymer of the esterified copolymer And at least one other performance additive addition and mixing of the body, and other dispersants in addition to the copolymer the esterification, to spread the oxidation product comprising providing a lubricant composition containing less than 2.5wt%.

This aspect relates to a lubricating composition containing an esterified copolymer ("copolymer") as disclosed herein, wherein the copolymer comprises a unit derived from a polymerizable vinyl aliphatic monomer and an alpha, beta -ethylenically unsaturated dicarboxylic acid Or a derivative thereof (hereinafter collectively referred to as a carboxylic acid monomer). According to one embodiment, the exemplary copolymer can reduce the oxidizing effect of the lubricating composition when used in machinery. According to one embodiment, the copolymer is useful as a base oil substitute in a lubricating composition. Another aspect relates to a method of lubricating a mechanical device with a lubricating composition. An exemplary mechanical device is a vehicle power transmission device, including a gear or transmission system.

The lubricating composition is substantially free of dispersants. "Substantially absent" means that the lubricating composition formulated for use in a powertrain system is compatible with all other dispersants other than the exemplary antistatic copolymer, which provides dispersion of the oxidation products generated during use of the lubricating composition in the machine By weight or less in total. For example, the lubricating composition may contain from 0 to 2.5 wt%, or 2 wt% or less, or 1.75 wt% or less, or 1.5 wt% or less, 1 wt% or less, 0.5 wt% or less of the dispersant (s) , 0.25 wt% or less, 0.2 wt% or less, 0.1 wt% or less, or 0.01 wt% or less. The amount of dispersant excludes any oil or other diluent that may be mixed before adding the dispersant to the composition. According to one embodiment, the lubricating composition is free of a dispersing agent, meaning that the dispersing agent may be present in the lubricating composition in a trace amount of less than 0.001 wt% or less than 0.0001 wt%, but no dispersant added to the lubricating composition.

"Dispersing agent" means any performance additive conventionally added to the lubricating oil for dispersive characterization, particularly for dispersing the oxidation product generated in the lubricating composition during operation of a mechanical device such as a gear or transmission system. Such dispersants include, but are not limited to, ashless dispersants such as N-substituted long chain alkenyl succinimides, polyisobutylene succinimides complexed with zinc, Mannich bases, acylated polyalkylene polyamines, And a post-treated dispersant formed by polymerization. "Long chain" means a chain having at least 6, at least 12, 24 or 30 carbon atoms. Examples of such dispersants are set forth below, including that the sum total of all such dispersants is limited to the amounts provided herein, and according to one embodiment, the dispersant is absent (in trace amounts) in the exemplary lubricant composition.

The term "copolymer" as used herein generally refers to a polymer derived from two or more different monomers. An exemplary copolymer has a backbone derived from two (or more) other monomers.

Exemplary esterified copolymers disclosed herein include polymeric backbones comprising units derived from vinyl aliphatic monomers and units derived from carboxylic acid monomers. The backbone may be a chain containing units derived from selected monomers that are linked together so that the backbone comprises at least 10 such units, or at least 20 or at least 50 of such monomer units. According to one embodiment, the backbone chain of monomer units derived from the selected monomer has no more than 1000 of such monomer units, or no more than 500 of said monomer units or no more than 200 of said monomer units. In an exemplary copolymer, the majority of the backbone (e.g., at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, such as 70-95%, and up to 100% Vinyl aliphatic monomers and carboxylic acid monomers. The side groups may be grafted to the backbone by, for example, esterification and / or amidation / imidization of the backbone units derived from carboxylic acid monomers.

The polymeric backbone of the copolymer can generally be of alternating structure so that each carboxylic acid unit (or at least most of it) is separated from the next carboxylic acid unit by at least one vinyl aliphatic monomer unit, and each carboxylic acid unit is the same or different , And each vinyl aliphatic monomer unit may be derived from the same or different vinyl aliphatic monomers. The molar ratio of vinyl aliphatic monomer units to carboxylic acid monomer units present in the copolymer may be, for example, from 1: 3 to 3: 1, or from 0.6: 1 to 1.2: 1. According to one embodiment, the molar ratio is from about 0.7: 1 to 1: 1.1 in the copolymer. However, it should be noted that the molar ratio used in the preparation of the copolymer may differ from the molar ratio of the copolymer. Further, when the unit of the third monomer is present in the copolymer, the ratio of the vinyl aliphatic monomer unit to the carboxylic acid monomer unit may be slightly changed to accommodate this unit.

According to one embodiment, the main chain chain containing the selected monomer-derived units further contains units derived from the vinyl aromatic monomer in an amount of not more than 25%, not more than 15%, not more than 10%, or not more than 5% of the monomer units of the main chain Can be derived from vinyl aromatic monomers.

Exemplary copolymers further include ester groups formed by esterifying at least a portion of the carboxylic acid units of the copolymer with a primary alcohol such as one or more of linear alcohols and branched alcohols.

Exemplary esterified copolymers further include nitrogen containing groups (e.g., amino groups, amido groups and / or imidogroups) formed from, for example, nitrogen containing compounds that may be incorporated during copolymerization. According to one embodiment, the nitrogen-containing group forms a salt of the carboxylic acid unit, for example, by reacting the amine with the carboxylic acid unit without removing water.

(A) forming an esterified copolymer having a nitrogen-containing group, and (B) reacting the esterified copolymer formed in (A) with (i) an oil of lubricating viscosity and (ii) mixing with at least one other performance additive besides the exemplary copolymer. Step (A)

(I) reacting (i) a vinyl aliphatic monomer such as an alpha -olefin (and optionally, a vinyl aromatic monomer such as styrene) and (ii) a carboxylic acid monomer such as maleic acid or a derivative thereof such as maleic anhydride, , Wherein the carboxylic acid monomer optionally has an ester group derived from a primary alcohol or the like;

(2) optionally esterifying the copolymer of step (1) with a primary alcohol or the like to form an esterified copolymer; And

(3) optionally, copolymerizing the copolymer of step (2) with an esterified aerosol comprising from 0.01 wt% to 1.5 wt% (or 0.05 wt% to 0.75 wt%, or 0.075 wt% to 0.25 wt% With a nitrogen containing compound, such as a positive amine, which provides a coalescent, wherein the copolymer is esterified, for example, in one or more of steps (1), (2) and (3).

According to one embodiment, steps (1), (2) and (3) are performed respectively. According to one embodiment, the carboxylic acid monomer used in step (1) does not need to have an ester group.

According to another embodiment, the carboxylic acid monomer may be esterified by, for example, a primary alcohol prior to step (1), and step (2) may be omitted.

According to another embodiment, steps (1) and (3) are carried out and the nitrogen-containing compound provides an ester group, in which case step (2) can be omitted.

According to another embodiment, the esterified copolymer is substantially free of nitrogen-containing groups, i.e. contains up to 0.01 wt% nitrogen.

As an example, exemplary copolymers can include polymeric backbones of poly (alpha-olefin maleic anhydride) derived from maleic anhydride as 1-dodecene and carboxylic acid monomers as vinyl aliphatic monomers, (Alpha-olefin maleic anhydride diester) which is esterified by alcohol and esterified by grafting of the side chain to the main chain, and a nitrogen-containing compound (such as 4- (3-aminopropyl) morpholine or 1 - (2-aminoethyl) imidazolidinone) to provide an esterified copolymer wherein the nitrogen is from 0.01 to 1.5 wt%, for example from 0.05 to 0.2 wt%.

(I) a lubricating viscosity oil (sometimes referred to herein as a base oil) and, optionally, (ii) one or more other performance additives (more than the amount specified herein) Other than a dispersing agent).

The lubricating composition may also be prepared by mixing the exemplary copolymer with one or more other performance additives (other than a dispersant in an amount more than the amount specified herein) in the absence of oil of lubricating viscosity.

The lubricating composition may comprise from 5 to 75 wt%, or from 10 to 60 wt%, from 30 to 60 wt%, or from 40 to 50 wt% of the exemplary copolymer. Examples of lubricating compositions include 5 to 30 wt%, 5 to 20 wt%, 5 to 15 wt%, or 5 to 10 wt%, or 20 to 40 wt% of exemplary copolymers.

The weight average molecular weight (M _w ) used herein is measured by gel permeation chromatography (GPC), also known as size exclusion chromatography, using polystyrene standards. Typically, the weight average molecular weight is determined for the final esterified copolymer reacted with the final esterified copolymer and, optionally, the nitrogen containing compound. The M _w of the exemplary polymer prior to esterification may range from 3000 to 50,000, and in one embodiment may range from 3000 to 20,000, such as 10,000 or more.

After the esterification and selective reaction with the nitrogen-containing compound, the M _w of the exemplary polymer can range from 5000 to 50,000, and in one embodiment ranges from 5000 to 25,000, from 10,000 to 17,000, or from 5000 to 10,000, or from 12,000 To 18,000 or 9,000 to 15,000, or from 15,000 to 20,000.

The viscosity of the copolymer (e.g., in a lubricating composition) can be measured under ambient conditions, at low temperatures (Brookfield viscosities), or under shear conditions. The viscosity shear stability index (SSI) of the transmission lubricant, which measures the stability of the copolymer in the lubricating composition under shear conditions, is determined by a 20 hour KRL test as set forth in standard CEC L-45-99 and DIN 51350-6-KRL / C Tapered Bearing Roller Test). The 20 hr KRL SSI of the exemplary lubricant composition is applied to the surface of the roller at 0-30 SSI, or 0-10 SSI, or 10-30 SSI, when treated with the pointed roller bearing shear (5000N, 1475 RPM, 60 C) under the CEC L- SSI (i.e., low permanent shear loss).

One way to evaluate the ability of an exemplary copolymer to improve the dispersion of oxidizing materials is to evaluate the oxidation stability of lubricating compositions. This method is based on CEC L-48-00 [Oxidation Stability of Lubricating Oils used in Automotive Transmissions by Artificial Aging (Laboratory Test) available from the Coordinating European Council for the development of performance tests for fuels, lubricants, and other fluids (CEC) Lt; RTI ID = 0.0 > DKA < / RTI > In an exemplary method, the test proceeds using an oxidation procedure as described in CEC L-48-00 Procedure B where air is passed through 100 ml of oil at a rate of 5 liters / hr for 192 hours at 160 占 폚. The results are expressed as the rate of increase in kinetic viscosity at 40 ° C (KV 40%) and 100 ° C (KV 100%). Typically, the lower the value recorded as the percent increase in KV100, the better the performance.

In addition, the test that was used to measure the dispersion state of the lubricant composition, which was the test oil that had been treated with the oxidation test or the test oil that was used in the front line engine, was to evaluate the relative undistributed sludge spot size of the oil that was located on the sorbent material . This method entails placing a measured drop of oxidized oil (at room temperature) on the foliar center using a disposable pipette to keep the spot evolving. The papers are placed in a drying oven at 80 ° C (± 10 ° C) for 1 hour (± 15 minutes). The dispersed oil sample appears as a circular spot on the sorbent material, while any microdispersed sludge may appear as a darker inner circular spot. The distribution rating is calculated as follows:

Copolymer

A. Vinyl Aliphatic Monomer Units

The copolymer includes vinyl aliphatic monomer units derived from vinyl aliphatic monomers. Exemplary vinyl aliphatic monomers are aliphatic compounds substituted with polymerizable aliphatic monomers, particularly vinyl groups (-CH = CH ₂ ). Examples of vinyl aliphatic monomers include C ₈ -C ₂₀ alpha-olefins, or alpha-olefins selected from C ₆ -C ₃₀ alpha-olefins such as C ₁₀ -C ₁₈ alpha-olefins, or C ₁₀ -C ₁₄ alpha-olefins . The alpha-olefin may be linear or branched. Examples of suitable linear alpha-olefins include 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, Decene, and mixtures thereof. One example of a useful vinyl aliphatic monomer is 1-dodecene.

B. Carboxylic acid monomer unit

The alpha, beta -ethylenically unsaturated carboxylic acid or derivative thereof used to form the carboxylic acid unit of the copolymer may be a dicarboxylic acid or an anhydride thereof, or a completely esterified, partially esterified, or other derivative thereof, . When partially esterified, other functional groups may include acids, salts or mixtures thereof. Suitable salts include alkali metals, alkaline earth metals and mixtures thereof. The salt may comprise lithium, sodium, potassium, magnesium, calcium or a mixture thereof.

Exemplary unsaturated carboxylic acids or derivatives thereof that may be used to form the carboxylic acid units of the copolymer include acrylic acid, methyl acrylate, methacrylic acid, maleic acid, fumaric acid, itaconic acid, alpha-methylene glutaric acid and its anhydrides and mixtures, Substituted < / RTI > equivalents thereof. Examples of monomers suitable for forming carboxylic acid units include itaconic anhydride, maleic anhydride, methyl maleic anhydride, ethyl maleic anhydride, dimethyl maleic anhydride, and mixtures thereof. According to one embodiment, the carboxylic acid unit comprises units derived from maleic anhydride or derivatives thereof.

According to exemplary unsaturated carboxylic acids or derivatives thereof, the carbon-carbon double bond is typically in alpha, beta-position (e.g., itaconic acid, an anhydride or ester thereof) to at least one of the carboxy functionalities, (E.g., maleic acid or an anhydride thereof, fumaric acid, or an ester thereof) to the dicarboxylic acid, its anhydride, or the two carboxy functional groups of the ester. According to one embodiment, the carboxy functionality of these compounds will be separated by not more than 4 carbon atoms, such as 2 carbon atoms.

Other monomers suitable for forming carboxylic acid monomer units of the exemplary copolymers are described in U.S. Publication No. 20090305923.

C. Optional units

According to one embodiment, in addition to the vinyl aliphatic monomer unit and the carboxy monomer unit, the backbone chain may further include other monomer-derived units capable of polymerizing with either or both of the vinyl aliphatic monomer unit and the carboxy monomer unit . These additional units may be randomly distributed throughout the copolymer backbone, or may exist in the form of blocks or blocks. The copolymer may contain up to 30 mole%, up to 20 mole%, or up to 10 mole% total of such optional units. An example of such an optional unit is derived from a vinyl aromatic monomer or (meth) acrylate. Exemplary vinyl aromatic monomers, if present, are polymeric aromatic monomers, especially aromatic compounds substituted with vinyl groups (-CH = CH ₂ ).

Suitable vinyl aromatic monomers correspond to formula I:

Formula I

In this formula, R ¹ and R ² independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a halogen-containing group. The vinyl aromatic monomer may be selected from styrene, alpha-alkyl styrene, nuclear alkyl styrene, chlorostyrene, dichlorostyrene, vinyl naphthalene, and mixtures thereof. Specific examples include styrene, alpha-methylstyrene, alpha-ethylstyrene, alpha-isopropylstyrene, alpha-tert-butylstyrene, Alpha-methylstyrene, m-isopropyl-alpha-methylstyrene, m-methyl-alpha-methylstyrene, Styrene, p-isopropylstyrene, vinylnaphthalene, and mixtures thereof.

D. Alcohols for esterification of carboxylic acid units

The carboxylic acid units of the copolymer may be completely or partially esterified by primary alcohols. The ester group is usually formed by reacting a carboxy-containing copolymer with an alcohol, but according to some embodiments, in the case of a lower alkyl ester, an ester group can be incorporated from one of the monomers used to prepare the copolymer.

Suitable primary alcohols for use herein may contain from 8 to 60, from 8 to 40, from 8 to 24, or from 8 to 16 carbon atoms, such as from 8 to 10 carbon atoms. The primary alcohols may be linear, or may be branched at < RTI ID = 0.0 > a- or < / RTI > According to one embodiment, a mixture of a linear alcohol and a branched alcohol is used to form the esterified copolymer described herein. According to an exemplary embodiment, at least 0.1% of the carboxylic acid units in the copolymer are esterified by branched alcohols at the? - or higher position.

According to one embodiment, from 20 to 100 mol%, from 30 to 100 mol%, or from 30 to 70 mol%, based on the total number of moles of carboxyl groups present in the copolymer, is in the alcohol group (i. E., The alcohol-derived or alkoxy moiety of the ester) 70 or 80 to 100 mol%, alternatively 80 to 30 mol%, based on the total number of moles of carboxyl groups in the copolymer, contain ester groups of 12 to 19 carbon atoms and contain ester groups of 8 to 10 carbon atoms in the alcohol moiety do. According to one embodiment, the esterified copolymer contains an ester group of 12 to 18 carbon atoms present at the alcohol moiety in an amount of at least 45 mol%, based on the mole of the carboxyl group of the esterified copolymer. According to an optional embodiment, the esterified copolymer has an ester group of 1 to 6 carbon atoms present in the alcohol moiety at 20 mol% or less, 0 to 5%, or 1 to 5 mol%, based on the total number of moles of carboxyl groups present in the copolymer 2%. According to one embodiment, the composition is substantially free of ester groups having from 3 to 7 carbon atoms.

According to one embodiment, from 0.1 to 99.89 (or from 1 to 50, or from 2.5 to 20, or from 5 to 15) percent of the esterified carboxylic acid units are esterified with a branched primary alcohol at? Or more positions , 0.1 to 99.89 (or 1 to 50, or 2.5 to 20, or 5 to 15)% of the esterified carboxylic acid units are esterified with a linear alcohol or alpha-branched alcohol and from 0.01 to 10% Or from 0.1% to 20%, alternatively from 0.02% to 7.5%, alternatively from 0.1% to 5%, alternatively from 0.1% to less than 2%) of at least one nitrogen-containing group such as amino-, amido- and / And / or a salt formed between the amine and the carboxylic acid as described below. As an example, 5 to 15% of the carboxylic acid units of the copolymer are esterified with primary alcohols branched at the beta or higher position and from 0.1 to 95% of the carboxylic acid units are linear alcohols or alpha-branched alcohols And less than 0.1 to 2% of the carboxylic acid units have at least one nitrogen-containing group.

Examples of useful primary alcohols include butanol, heptanol, octanol, 2-ethylhexanol, decanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol And combinations thereof.

Other exemplary primary alcohols include commercially available mixtures of alcohols. Such alcohols include, for example, oxoalcohols which may include various mixtures of alcohols having 8 to 24 carbon atoms. Of the various commercially available alcohols useful herein, one contains from 8 to 10 carbon atoms and the other contains from 12 to 18 aliphatic carbon atoms. The alcohol present in the mixture may include one or more of, for example, octyl alcohol, decyl alcohol, dodecyl alcohol, tetradecyl alcohol, pentadecyl alcohol and octadecyl alcohol. Various suitable sources of such alcohol blends are those of the technical grade marketed under the trade name NEODOL® alcohol (Shell Oil Company, Houston, Tex.) And the trade name ALFOL® alcohol (Sasol, Westlake La.) And fatty acids derived from animal and vegetable fats Alcohol, and is commercially available, for example, by Henkel, Sasol, and Emery.

The tertiary alkanolamine, i. E., N, N-di- (lower alkyl) aminoalkanolamine, is the other alcohol that can be used to prepare the esterified copolymer. Examples include N, N-dimethylethanolamine, N, N-diethylethanolamine, 5-diethylamino-2-pentanol and combinations thereof.

Examples of branched primary alcohols at the? - or higher position may include Guerbet alcohols. Methods for making gerbercohols are disclosed in U.S. Patent No. 4,767,815 (column 5, line 39 to column 6, line 32).

The branched primary alcohol at < RTI ID = 0.0 > 1- or < / RTI > more positions can be used to provide branching as indicated in ( _w )

(II)

In this equation,

(BB) is a copolymer main chain containing a carboxylic acid monomer unit and a vinyl aliphatic monomer unit;

X is the copolymer as the main chain and () _y a branched hydrocarbyl linking group, (i) a functional group containing at least one oxygen or nitrogen atom with the carbon or (ii) 1 to 5 carbon atoms (typically contained in the , -CH ₂ -);

w is the number of side groups attached to the copolymer backbone and may range from 2 to 2000, from 2 to 500, or from 5 to 250;

y is 0, 1, 2 or 3 with the proviso that at least 1 mol% of the group is not equal to 0; When y is 0, X is bonded to the terminal group in a manner sufficient to satisfy the valency of X, wherein the terminal group is selected from the group consisting of hydrogen, alkyl, aryl, metal (typically introduced during neutralization of the ester reaction, , Magnesium, barium, zinc, sodium, potassium or lithium) or an ammonium cation, and mixtures thereof;

p is an integer in the range of 1 to 15 (or 1 to 8, or 1 to 4);

R ³ and R ⁴ are independently a linear or branched hydrocarbyl group and the total number of carbon atoms present in R ³ and R ⁴ is at least 12 (or at least 16, at least 18, or at least 20 )to be.

According to other aspects, the copolymer having a side group may contain from 0.10% to 100%, from 2% to 20%, such as from 5% to 10% of the branched hydrocarbyl group designated as the group in ( _y ) 20%, or 10% to 18% by weight of the composition. The side groups of formula (II) may also be used to define ester groups as defined earlier in the phrase "primary alcohol branched at? - or more positions".

According to other embodiments, the functional group defined in the general formula II with X is _{-CO 2 -, -C (O)} N = or - (CH _{2) v} - can include at least one of a, where v is from 1 to 20, 1 to 10, or 1 to 2.

According to one embodiment, X is derived from an alpha, beta-ethylenically unsaturated dicarboxylic acid or derivative thereof. Examples of suitable carboxylic acids or derivatives thereof generally include maleic anhydride, maleic acid, (meth) acrylic acid, itaconic anhydride or itaconic acid. According to one embodiment, the alpha, beta -ethylenically unsaturated dicarboxylic acid or derivative (s) thereof can be at least one of maleic anhydride or maleic acid.

According to one embodiment, X is other than an alkylene group linking the copolymer backbone and the branched hydrocarbyl group.

According to other embodiments, the group can be an esterified, amidated or imidized functional group.

Examples of suitable groups for R ³ and R ⁴ in formula II is C _{15 -16-alkyl} group containing a polymethylene group such as 2-C _{1 -15} alkyl-hexadecyl groups (e.g., 2-octyl-hexadecyl) and 2 Alkyl-octadecyl groups (e.g., 2-ethyloctadecyl, 2-tetradecyl-octadecyl and 2-hexadecyloctadecyl); Examples of the alkyl group containing a C _{13 -14} polymethylene group such as a 1-C _{1 -15} alkyl-tetradecyl group (e.g., 2-hexyltetradecyl, 2-decyltetradecyl and 2-undecyltridecyl) _{1 -15} alkyl-hexadecyl groups (e.g., 2-ethyl-hexadecyl and 2-dodecylhexadecyl); C _{10 -12} polyalkyl group such as 2-C _{1 -15} alkyl group-containing methylene-dodecyl group (e.g., 2-octyldodecyl) and 2-C _{1 -15} alkyl-dodecyl groups (2-dodecyl hexadecyl chamber, and 2-octyldodecyl), 2-C _{1 -15} alkyl-tetradecyl groups (e.g., 2-hexyl-tridecyl and 2-decyltetradecyl); Examples of alkyl groups containing C _{6 -9} polymethylene groups, such as 2-C _{1 -15} alkyl-decyl groups such as 2-octyldecyl and 2,4-di-C _{1 -15} alkyl- Ethyl-4-butyl-decyl); An alkyl group containing a C _{1 -5} polymethylene group such as 2- (3-methylhexyl) -7-methyldecyl and 2- (1,4,4-trimethylbutyl) -5,7,7-trimethyl- ; And at least two branched alkyl groups, such as propylene oligomer (hexamer to undecyl kameo), ethylene / propylene (molar ratio 16: 1-1: 11) oligomer, isobutene oligomer (penta to octa Murray Murray), and C _{5 -17} and mixtures of alkyl moieties of oxoalcohols corresponding to alpha-olefin oligomers (dimers to hexamers).

The number of carbon atoms in R ³ and R ⁴ may range from 12 to 60, 14 to 50, 16 to 40, 18 to 40, or 20 to 36 total carbon atoms.

R ³ and R ⁴ may each individually contain 5 to 25, 8 to 32 or 10 to 18 methylene carbon atoms. According to one embodiment, the number of carbon atoms on each R < ³ > and R < ⁴ > groups may be from 10 to 24.

According to other embodiments, the primary alcohol branched at the? - or higher position may have at least 12 (or at least 16, at least 18 or at least 20) carbon atoms. The number of carbon atoms can range from at least 12 to 60, or at least 16 to 30. [

Suitable examples of primary alcohols branched at the? - or higher position include 2-ethylhexanol, 2-butyloctanol, 2-hexyldecanol, 2-octyldodecanol, And mixtures thereof.

E. Nitrogen-containing group

Exemplary esterified copolymers include nitrogen-containing groups such as amino-, amido- and / or imido-groups. Nitrogen containing groups are formed from nitrogen-containing compounds, such as amines, amides, imides, or mixtures thereof, which can be incorporated during copolymerisation (or through reaction with carboxylic acid units to form salts), for example, (Including forming a salt of a carboxylic acid unit as used herein), through amidation and / or imidation.

Examples of suitable nitrogen-containing compounds that may be incorporated into the copolymer include N, N-dimethyl acrylamide, N-vinylcarbamides such as N-vinyl-formamide, N-vinylacetamide, N-vinyl propionamide, N Vinyl pyrrolidone, N-vinyl caprolactam, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminobutylacrylamide, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, Propyl methacrylate, dimethylaminopropylacrylamide, dimethylaminopropyl methacrylamide, dimethylaminoethylacrylamide, and mixtures thereof.

The copolymer may usually contain a nitrogen-containing group capable of reacting with the esterified copolymer backbone for capping of the copolymer backbone. Capping can yield copolymers with ester, amide, imide and / or amine groups.

The nitrogen-containing groups may be derived from primary or secondary amines such as aliphatic amines, aromatic amines, aliphatic polyamines, aromatic polyamines, polyaromatic polyamines or combinations thereof.

According to one embodiment, the nitrogen-containing groups may be derived from aliphatic amines such as C ₁ -C ₃₀ or C ₁ -C ₂₄ aliphatic amines. Examples of suitable aliphatic amines include aliphatic monoamines and diamines which may be linear or cyclic. Examples of suitable primary amines are methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, But are not limited to, oleylamine, dimethylaminopropylamine, diethylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine and dibutylaminoethylamine. Examples of suitable secondary amines include dimethylamine, diethylamine, dipropylamine, dibutylamine, diamylamine, dihexylamine, diheptylamine, methylethylamine, ethylbutylamine, diethylhexylamine, and ethylamylamine . Secondary amines include cyclic amines such as aminoethyl morpholine, aminopropyl morpholine, 1- (2-aminoethyl) pyrrolidone, piperidine, 1- (2- aminoethyl) piperidine, Lt; / RTI > Examples of suitable aliphatic polyamines include tetraethylene pentamine, pentaethylene hexamine, diethylene triamine, triethylene tetramine, and polyethyleneimine.

According to another embodiment, the nitrogen-containing group may be derived from an aromatic amine. Aromatic amines include those that may be represented by the formula NH ₂ -Ar or T-NH-Ar, wherein T may be alkyl or aromatic, Ar is an aromatic group such as a nitrogen containing aromatic group, Includes any of the following structures as well as a number of non-condensed or fused aromatic rings:

In such a structure and associated structure, R ^5, R ⁶ and R ⁷ are independently of other groups disclosed herein, -H, -C _{1 -18} alkyl group, a nitro group, -NH-Ar, -N = N -Ar , -NH-CO-Ar, -OOC -Ar, -OOC-C 1 -18 alkyl, -COO-C _{1 -18 alkyl, -OH, -O- (CH 2 CH} 2 0) n C 1 -18 alkyl And -O- (CH ₂ CH ₂ O) _n Ar, wherein n is 0 to 10.

Examples of aromatic amines include amines in which the carbon atoms of the aromatic ring structure are attached directly to the amino nitrogen. The aromatic amine may be a monoamine or a polyamine. The aromatic ring may be a mononuclear aromatic ring (a ring derived from benzene), but may include a fused aromatic ring, especially a ring derived from naphthalene. Examples of aromatic amines include aniline, N-alkyl anilines such as N-methylaniline and N-butyl aniline, di- (para-methylphenyl) amine, 4-aminodiphenylamine, N, N-dimethylphenylenediamine, Amine, 4- (4-nitrophenyl-azo) aniline (Disperse Orange 3), sulfamethazine, 4-phenoxyaniline, 3-nitroaniline, 4- aminoacetanilide Amide), 4-amino-2-hydroxy-benzoic acid phenyl ester (phenylaminosalicylate), N- (4-amino- phenyl) -benzamide, various benzylamines such as 2,5-dimethoxybenzylamine , 4-phenylazoaniline, and combinations thereof and substituted versions thereof. Other examples include para-ethoxy aniline, para-dodecyl aniline, cyclohexyl-substituted naphthyl amine, and thienyl-substituted aniline. Examples of other suitable aromatic amines include amino-substituted aromatic compounds and amines in which the amine nitrogen is part of an aromatic ring such as 3-aminoquinoline, 5-aminoquinoline and 8-aminoquinoline. Also included are aromatic amines, such as 2-aminobenzimidazole, which contains one secondary amino group attached directly to the aromatic ring and a primary amino group attached to the imidazole ring. Other amines include N- (4-anilinophenyl) -3-aminobutanamide, and 3-aminopropyl imidazole, and 2,5-dimethoxybenzylamine.

Additional aromatic amines and related compounds are disclosed in U.S. Patent Nos. 6,107,257 and 6,107,258. Examples thereof include aminocarbazole, benzimidazole, aminoindole, aminopyrrole, amino-indazolinone, aminopiperidine, mercaptotriazole, aminophenothiazine, aminopyridine, aminopyrazine, aminopyrimidine, pyridine, Pyrazine, pyrimidine, aminothiadiazole, aminothiothiadiazole and aminobenzotriazole. Other suitable amines include 3-amino-N- (4-anilinophenyl) -N-isopropylbutanamide and N- (4-anilinophenyl) -3- { Amino} butanamide. Other aromatic amines that may be used include various aromatic amine dye intermediates containing a plurality of aromatic rings linked by an amide structure or the like. Examples thereof include materials of the following formulas and isomeric variations thereof:

Wherein R ⁸ and R ⁹ are independently an alkyl or alkoxy group such as methyl, methoxy or ethoxy.

According to one example, R ⁸ and R ⁹ are both -OCH ₃ and this material is known as Fast Blue RR [CAS # 6268-05-9]. According to another example, R ⁹ is -OCH ₃ and R ⁸ is -CH ₃ , which is known as Fast Violet B [99-21-8]. When both R ⁸ and R ⁹ are ethoxy, this material is known as Fast Blue BB [120-00-3]. United States Patent 5,744, 429 discloses other aromatic amines useful in the present invention, particularly aminoalkyl phenothiazines. N-aromatic substituted acid amide compounds such as those disclosed in U.S. Publication No. 2003/0030033 may also be used in the present invention. Suitable aromatic amines include the amine substituents, that is, the amine nitrogen is not one of the sp ² hybridization in the aromatic ring on the amine nitrogen is an aromatic carboxy compound.

The aromatic amine may have an NH group capable of condensation with a carbonyl-containing side group. Certain aromatic amines are commonly used as antioxidants. Examples thereof include alkylated diphenylamines such as nonyldiphenylamine and dinonyldiphenylamine. As long as these materials are condensed with carboxy functional groups of the polymer chain, they are suitable for use in the present invention. However, two aromatic groups attached to amine nitrogen are believed to reduce reactivity. Accordingly, the appropriate amine is included to hold the hydrocarbyl alkyl groups of one of the bill substituent is a relatively short chain such as methyl is secondary nitrogen atom, or a primary nitrogen atom (-NH _2). Among such aromatic amines are 4-phenyl azoaniline, 4-aminodiphenylamine, 2-aminobenzimidazole, and N, N-dimethylphenylenediamine. Some of these aromatic amines and other aromatic amines can also impart antioxidant performance as well as dispersibility and other properties to the copolymer.

According to one embodiment, the amine component of the copolymer further comprises an amine having at least two N-H groups capable of condensing with the carboxy functionality of the copolymer. This material is hereinafter referred to as the "binding amine" because it can be used to bind two copolymers containing carboxylic acid functional groups together. High molecular weight materials have been observed to be able to provide improved performance, which is one way to increase the molecular weight of a material. The associative amine may be an aliphatic amine or an aromatic amine; An aromatic amine is one that is believed to be an additional component different from the aromatic amine described above and will usually have only one condensed or reactive NH group to avoid excessive cross-linking of the copolymer chain. Examples of such associative amines include ethylenediamine, phenylenediamine and 2,4-diaminotoluene; Other examples include propylene diamine, hexamethylenediamine and other ω-polymethylenediamines. The amount of reactive functional groups on such conjugated amine can be reduced if necessary by reaction with less than stoichiometric amount of a blocking material, such as hydrocarbyl-substituted succinic anhydride.

According to one embodiment, exemplary copolymers provide for oxidation control. Typically, the oxidatively modifying copolymer contains incorporated residues of amine-containing compounds such as morpholine, pyrrolidinone, imidazolidinone, amino amides (e.g., acetamide), beta -alanine alkyl esters, do. Examples of suitable nitrogen-containing compounds include 3-morpholin-4-yl-propylamine, 3-morpholin-4-yl-ethylamine, Lt; / RTI > alkyl ester) or mixtures thereof.

According to one embodiment, compounds based on imidazolidinones, cyclic carbamates or pyrrolidinones can be derived from compounds of the formula:

In this equation,

X is -OH or NH _2, and;

Hy "is hydrogen or a hydrocarbyl group (typically alkyl, C _{1 -4} - or C ₂ - alkyl), and;

Hy is hydro hydrocarbylene group (typically alkylene, C _{1 -4} - or C ₂ - alkylene), and;

Q is>NH,>NR,> CH ₂ ,>CHR,> CR ₂ or -O- (usually> NH or> NR) and R is C _1-4 alkyl.

According to one embodiment, the imidazolidinone is 1- (2-amino-ethyl) -imidazolidin-2-one (which may be referred to as aminoethylethylene urea) (3-amino-propyl) -pyrrolidin-2-one, 1- (2-hydroxy-ethyl) -imidazolidin- -Amino-ethyl) -pyrrolidin-2-one, or mixtures thereof.

According to one embodiment, the aminoamide comprises an acetamide which may be represented by the formula:

In this equation, Hy is hydro hydrocarbylene group (typically alkylene, or C _{1 -4} - or C ₂ - alkylene), and;

Is - (methyl or normal alkyl, or C _{1 -4)} Hy 'is a hydrocarbyl group.

Examples of suitable acetamides include N- (2-amino-ethyl) -acetamide or N- (2-amino-propyl) -acetamide.

According to one embodiment, the beta -alanine alkyl ester can be represented by the formula:

In this formula, R < ¹⁰ > is an alkyl group having 1 to 30 carbon atoms or 6 to 20 carbon atoms.

Examples of suitable? -Alanine alkyl esters include? -Alanine octyl ester,? -Alaninedesyl ester,? -Alanine 2-ethylhexyl ester,? -Alaninedesyl ester,? -Alanine tetradecyl ester or? -Alanine hexadecyl ester .

According to one embodiment, the copolymer is selected from the group consisting of 1- (2-amino-ethyl) -imidazolidin-2-one, 4- (3- aminopropyl) morpholine, 3- (dimethylamino) Phenylenediamine, N- (3-aminopropyl) -2-pyrrolidinone, aminoethylacetamide, β-alanine methyl ester, 1- (3-aminopropyl) imidazole and mixtures thereof Lt; / RTI >

According to one embodiment, the copolymer can be reacted with an amine-containing compound selected from morpholine, imidazolidinone, and mixtures thereof.

According to one embodiment, the nitrogen-containing compound is selected from the group consisting of 1- (2-aminoethyl) imidazolidinone, 4- (3-aminopropyl) morpholine, 3- (dimethylamino) - phenylenediamine, N- (3-aminopropyl) -2-pyrrolidinone, aminoethylacetamide, [beta] -alanine methyl ester, 1- (3-aminopropyl) imidazole and combinations thereof.

According to one embodiment, the nitrogen-containing compound is a non-dispersible nitrogen compound having only a single reactive nitrogen group. The reactive nitrogen group is a primary nitrogen group or a secondary nitrogen group, i.e., a nitrogen group having at least one hydrogen atom on nitrogen. For example, the nitrogen-containing compound may be substantially free of the dispersible nitrogen-containing compound (i.e., 2.5 mol% or less, 0.1 mol% or less or 0 mol% (S) that are more reactive than those involved in the reaction with the coalescent, leaving a reactive nitrogen group on the final copolymer.

The ester and / or nitrogen containing groups may be present in the copolymer in an amount of from 0.01 wt% to 1.5 wt% (or 0.02 wt% to 0.75 wt%, or 0.04 wt% to 0.25 wt%, or 0.2 wt% to 0.8 wt% .

I. Preparation of Copolymers

A. Formation of copolymer backbone

The copolymer may optionally be prepared in the presence of a free radical initiator, a solvent or a mixture thereof. It will be appreciated that varying the initiator amount may change the number average molecular weight of the exemplary copolymer.

The copolymer backbone can be prepared by reacting a vinyl aliphatic monomer with a carboxylic acid monomer.

The solvent may be a liquid organic diluent. Generally, the solvent has a boiling point high enough to provide the requisite reaction temperature. Exemplary diluents include toluene, t-butylbenzene, benzene, xylene, chlorobenzene, various petroleum fractions with a boiling point above 125 캜, and mixtures thereof.

The free radical initiator may include pyrolyzing as one or more peroxy compounds, such as peroxides, hydroperoxides, and azo compounds to provide free radicals. Other suitable examples are described in J. Brandrup and E.H. Immergut, Editor, "Polymer Handbook ", 2nd edition, John Wiley and Sons, New York (1975), pages II-1 to II-40. Examples of free radical initiators include those derived from free radical-generating reagents such as benzoyl peroxide, t-butyl perbenzoate, t-butyl methacloropherbenzoate, t-butyl peroxide, sec-butyl Butyl peroxide, t-butyl peroxide, t-amyl peroxide, cumyl peroxide, t-butyl peroctoate, t-butyl-m-chloroperbenzoate, ≪ / RTI > azobisisobaloronitrile, and mixtures thereof. According to one embodiment, the free radical generating reagent is selected from the group consisting of t-butyl peroxide, t-butyl hydroperoxide, t-amyl peroxide, cumyl peroxide, t-butyl peroctoate, t-butyl- , Azobisisobalonitrile, or mixtures thereof. Commercially available free radical initiators include the class of compounds sold by Akzo Nobel under the trade designation Trigonox®-21.

Exemplary backbone polymers can be prepared as follows: The alpha-olefin is reacted with maleic anhydride in the presence of a radical initiator and optionally a solvent. A solvent such as toluene may be used to dilute the monomer concentration and reduce the backbone length through chain transfer to a benzylic proton. Scheme 1 shows an example in which the alpha-olefin is 1-dodecene, the initiator is tert-butylperoxy-2-ethylhexanoate (sold under the trade designation Trigonox 21S by Akzo Nobel) and the solvent is toluene.

Scheme 1:

In this formula, n and m are independently integers of at least 1, such as 1 to 10, 1 to 5, or 1 to 3, for each segment (represented by two asterisks) of the copolymer. As you know, the final backbone copolymer can retain irregular changes in n and m.

B. Esterification

Esterification of exemplary backbone copolymers (or ester exchange reactions where the copolymer already contains ester groups and other types of ester groups are required) can be accomplished by reacting any of the copolymers described above and one or more preferred alcohols and / or alkoxylates By heating under typical conditions in the practice of the invention. Such conditions include, for example, a temperature of at least 80 캜, such as at most 150 캜 or higher, but the temperature should be maintained below the lowest decomposition temperature of any component of the reaction mixture or its product. Water or lower alcohols are usually removed when the esterification proceeds. Such conditions may include an organic solvent or diluent, such as a mineral oil, toluene, benzene, xylene or analogous thereto, and an esterification catalyst, such as one or more toluene sulfonic acids, sulfuric acid, aluminum chloride, The use of boron trifluoride-triethylamine, methanesulfonic acid, trifluoro-methanesulfonic acid, hydrochloric acid, ammonium sulfate and phosphoric acid. A more detailed description of the performance of the esterification can be found in column 11 of U.S. Patent 6,544,935.

According to one embodiment, at least 75%, or in certain embodiments at least 80%, at least 90%, or 95% to 98% of the carboxy functional groups of the copolymer are esterified. Most or all of the remaining carboxy functionality unconverted to the ester group will then be converted to a nitrogen-containing group. An excess of alcohol and / or alkoxylate over the stoichiometric amount required for complete esterification of the carboxy functional group can be used in the esterification process as long as the ester content of the polymer remains within a suitable range, such as in the range of 80 to 85%. Excessive alcohols and alkoxylates or unreacted alcohols and alkoxylates need not be removed since such alcohols and alkoxylates may serve as diluents or solvents for example the exemplary lubricating compositions. Likewise, an optional reaction medium, such as toluene, does not need to be removed as it can also act as a diluent or solvent in the lubricating composition. According to another embodiment, unreacted alcohols, alkoxylates and diluents are removed by known techniques such as distillation.

Scheme 2 illustrates the case where the main chain copolymer of Reaction Scheme 1 is esterified. Esterification dissolves the copolymer in the oil, and also improves the low temperature viscosity and improves the viscosity index of the lubricating composition containing the esterified copolymer. Example shown is used in a methane-sulfonic acid a linear primary C _{8 -10} alcohol mixture (trade name Alfol easily available from Sasol as 810 ™) and 2-hexyl-decan-1-ol (easily available from Sasol under the trade name Isofol 16 ™). R and R 'are independently selected from linear C _{8 -10} alkyl, and 2-hexyl decyl.

Scheme 2:

C. Formation of nitrogen-containing groups in the copolymer backbone

The nitrogen-containing compound can be reacted directly on the copolymer backbone by grafting an amine or other nitrogen-containing functional group onto the copolymer backbone, either (i) in a solution using a solvent, or (ii) under reactive extrusion conditions, . The amine-functional monomer can be grafted onto the copolymer backbone in a number of ways. According to one embodiment, grafting occurs by heat treatment through a "en" reaction. According to one embodiment, grafting occurs by Friedel-Crafts acylation reaction. According to another embodiment, the grafting is carried out in solution or in solid form via a free radical initiator. Solution grafting is a well known method for producing grafted copolymers. In this method, the reagent is introduced as such or as a solution in a suitable solvent. The desired copolymer product can then be separated from the reaction solvent and / or impurities by a suitable purification step.

According to one embodiment, the nitrogen-containing compound is introduced directly onto the copolymer backbone by free radical catalyzed grafting of the copolymer in a solvent such as an organic solvent such as benzene, t-butylbenzene, toluene, xylene, hexane, Can react. The reaction may be carried out in a mineral lubricating oil solution containing from 1 to 50 wt% or from 5 to 40 wt%, based on the initial total oil solution of the solvent, e.g. the copolymer, optionally in an inert environment at a temperature of from 100 DEG C to 250 DEG C or from 120 DEG C to 230 DEG C Lt; 0 > C, or 160 [deg.] C to 200 [deg.] C,

As an example, Scheme 3 illustrates that the residual anhydride group in the backbone copolymer produced by Scheme 1 after esterification in Scheme 2 is consumed with the primary amine (s). In Scheme 3, the functional group R can be selected to improve the dispersibility.

Scheme 3:

According to one embodiment, the amine may have more than one nitrogen, and the R group attached to the amine that reacts with the carboxylic acid monomer may contain at least one nitrogen atom, optionally substituted by a hydrocarbyl group, Aliphatic amines and aromatic amines. The hydrocarbyl group may be selected from aliphatic, aromatic, cyclic and acyclic hydrocarbyl groups. As amines, one or more of the following can be used: 1- (2-amino-ethyl) -imidazolidin-2-one, 4- (3- aminopropyl) morpholine, 3- Phenylamine, N- (3-aminopropyl) -2-pyrrolidinone, aminoethylacetamide,? -Alanine methyl ester and 1- (3-aminopropyl) imidazole .

According to another embodiment, the nitrogen-containing compound may be a monomer capable of polymerizing with both the vinyl aliphatic monomer and the carboxylic acid monomer so that the nitrogen-containing monomer is mixed into the main chain. For example, a free radical catalyzed reaction is used.

II. Lubricating composition

According to one embodiment, the lubricating composition contains an oil of lubricating viscosity and a unit derived from a vinyl aliphatic monomer and a carboxylic acid monomer as described above, and may be esterified by a primary alcohol, and the nitrogen- Lt; RTI ID = 0.0 > copolymers. ≪ / RTI > The lubricating composition may contain up to 2.5 wt% of a dispersant other than the exemplary copolymer to disperse the oxidized product generated during the use of the lubricating composition in the machine.

The lubricating composition may include oil of lubricating viscosity as a minor component or as a major component and may include, for example, 5 wt% or more, or 20 wt% or more, or 30 wt% or more, or 40 wt% or more of the lubricating composition. Lubricating compositions suitable for use in power transmission systems may include oils having a lubricating viscosity in an amount of 5 wt% or more, or 20 wt% or more, or 30 wt% or more of the lubricating composition. According to one embodiment, the oil of lubricating viscosity is less than 60 wt% of the lubricating composition.

According to one embodiment, the esterified copolymer is 5 to 95 wt% or 10 to 60 wt%, 30 to 60 wt%, or 40 to 50 wt% of the lubricating composition. Examples of lubricating compositions include 5 to 30 wt%, 5 to 20 wt%, 5 to 15 wt%, or 5 to 10 wt%, or 20 to 40 wt%, of the exemplary copolymer.

The ratio of the weight of oil of lubricating viscosity to the weight of exemplary copolymer present in the lubricating composition may range from 5:95 to 95: 5, or from 40:60 to 80:20. The ratio of the weight of the exemplary copolymer present in the lubricating composition to the weight of the dispersant may be 98: 2 to 100: 0, or 99: 1 to 100: 0, or 99.5: 0.5 to 100: 0.

According to some embodiments, the lubricant concentrate may be mixed with a base oil to form a lubricating composition. The lubricant concentrate may be formulated for a lubricating composition, but may contain lesser amounts of oil of lubricating viscosity, or no oil of lubricating viscosity, in a fully compounded lubricating composition. The lubricant concentrate may be combined with the additional oil to form a final lubricant in whole or in part so that the ratio of oil to copolymer and lubricant viscosity to oil and / or diluent oil is from 1:99 to 99: 1 ) Or from 80:20 to 10:90 (by weight).

The lubricating composition may contain, in addition to the exemplary copolymer and oils of lubricating viscosity, one or more additives such as one or more performance additives such as other viscosity index improvers, extreme pressure agents, antiwear agents, anti-scuffing agents, corrosion inhibitors and the like.

A. Oil of lubricating viscosity

Suitable oils of lubricating viscosity include natural and synthetic oils, oils derived from hydrocracking, hydrogenation and hydrofinishing, crude oils, refined oils and refinery oils, and mixtures thereof.

The crude oil is generally obtained directly from natural or synthetic sources without (or almost without) further purification.

A refined oil is similar to a crude oil except that it is further treated with one or more purification steps to improve one or more properties. Purification techniques are well known in the art and include solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, and the like.

Fiscal deficiencies are also known as reclaimed oils or reworked oils and are obtained by processes analogous to those used to obtain refined oils, often treated with techniques relating to the removal of further spent additives and oil degradation products .

Natural oils useful as oils of lubricating viscosity include animal or vegetable oils (e.g., castor oil or lard oil), mineral lubricating oils such as liquid petroleum oils and solvent-treated paraffinic, naphthenic or mixed paraffin- Acid-treated mineral lubricating oils, and oils derived from coal or shale, or mixtures thereof.

Synthetic lubricating oils useful as oils of lubricating viscosity include hydrocarbon oils such as polymerized and copolymerized olefins (e.g., polybutylene, polypropylene, propylene isobutylene copolymers); Poly (1-hexene), poly (1-octene), poly (1-decene), and mixtures thereof; Alkylbenzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di- (2-ethylhexyl) -benzene); Polyphenyls (e.g., biphenyl, terphenyl, alkylated polyphenyls); Alkylated diphenyl ethers and alkylated diphenyl sulfides and derivatives, analogs and analogs thereof, and mixtures thereof.

Other synthetic lubricating oils include polyol esters (e.g., Priolube® 3970), diesters, liquid esters of phosphorus-containing acids (eg, tricresyl phosphate, trioctyl phosphate and diethyl ester of decanephosphonic acid) And tetrahydrofuran. The synthetic oil may be produced in a Fischer-Tropsch reaction, typically a hydrogenated isomerized Fischer-Tropsch hydrocarbon or wax. According to one embodiment, the oil may be prepared by a Fischer-Tropsch gas-liquid synthesis procedure as well as other gas-liquid (GTL) oils.

In addition, oils of lubricating viscosity may be defined as specified in the American Petroleum Institute (API) Base Oil Compatibility Guidelines. The five base oil groups are: Group I (sulfur content> 0.03 wt%, and / or <90 wt% saturation, viscosity index 80-120); Group II (sulfur content ≤0.03 wt% and ≥90 wt% saturation, viscosity index 80-120); Group III (sulfur content ≤0.03 wt% and ≥90 wt% saturate, viscosity index ≥120); Group IV (all polyalphaolefins (PAO)); And Group V (everything else not included in Group I, II, III or IV). Exemplary lubricating viscosity oils include API Group I, Group II, Group III, Group IV, Group V oil or mixtures thereof. According to some embodiments, the oil of lubricating viscosity is API Group I, Group II, Group III or Group IV oil or a mixture thereof. According to some embodiments, the oil of lubricating viscosity is API Group I, Group II or Group III oil or a mixture thereof.

B. Performance additive

The lubricating composition described herein optionally further comprises at least one performance additive. Exemplary performance additives in addition to the copolymer include metal deactivators, detergents, dispersants (only in small quantities), viscosity index improvers, friction modifiers, corrosion inhibitors, antiwear agents, extreme pressure agents, anti-scuffing agents, antioxidants, An emulsifier, a pour point depressant, a seal swell agent, and mixtures thereof. Typically, a fully-formulated lubricant composition (or "oil") will contain one or more of these performance additives. Suitable amounts of such additives in exemplary lubricant compositions are set forth below. All of these quantities are shown on a no-oil basis, i.e. excluding any diluent.

1. Dispersant

As noted above, an exemplary fully-formulated lubricant composition has no or substantially no dispersant for dispersing other oxidation products besides the exemplary esterified copolymer. Examples of dispersants that can not be present in the lubricating composition at all or may exist only in limited amounts as indicated above are set forth below.

Exemplary dispersants are often known as ashless dispersants because they do not contain ash forming metal prior to mixing with the lubricating oil composition and generally do not contribute to any ash forming metals when added to lubricants and polymeric dispersants. The ashless dispersants are characterized by polar groups attached to relatively high molecular weight hydrocarbon chains. Typical ashless dispersants include succinimides, phosphonates, and combinations thereof.

Exemplary succinimides include N-substituted long chain alkenyl succinimides. Examples of N-substituted long chain alkenyl succinimides include poly (C3-C6 alkylene) succinimides such as polyisobutylene substituents having a number average molecular weight of from 350 to 5000, 500 to 3000, 1000 to 2500, Lt; RTI ID = 0.0 &gt; 2500. &Lt; / RTI &gt;

Exemplary high vinylidene polyisobutylenes that can be used to prepare succinimide dispersants are described, for example, in U.S. Patent Nos. 3,215,707; 3,231,587; 3,515,669; 3,579,450; 3,912,764; 4,605,808; 4,152,499; 5,071,919; 5,137,980; 5,286,823; 5,254,649.

Ethylene / alpha olefin copolymers that can be used to prepare succinimide dispersants are described, for example, in U.S. Patent Nos. 5,498, 809; 5,663,130; 5,705,577; 5,814,715; 6,022,929; And 6,030,930.

Other exemplary dispersants may be zinc and polyisobutylene succinimide complexes formed from polyisobutylene, amines, and zinc oxides.

Another class of ashless dispersants are the acylated polyalkylene polyamines of the type described in U.S. Patent No. 5,330,667.

Another class of ashless dispersants is the Mannich base. Mannich dispersants are the reaction products of aldehydes (especially formaldehyde) and amines (especially polyalkylene polyamines) and alkyl phenols. Alkyl groups generally contain at least 30 carbon atoms.

Various methods for preparing succinimide dispersants are known. For example, an exemplary dispersant can be a C3-C6 polyalkylene (e.g., polypropylene, polyisobutylene, polypentylene, polyheptylene) or a derivative thereof (e.g., a chlorinated derivative) Is reacted with an unsaturated dicarboxylic acid or an anhydride thereof (e.g., maleic anhydride or succinic anhydride) to obtain an acylated C3-C6 polyalkylene compound, and then reacted with a polyamine such as an amine or a polyethyleneamine such as a primary amine To obtain the above dispersant.

Some of the following references relate to the preparation of acylated C3-C6 polyalkylene compounds suitable for use in preparing succinimide dispersants, while other references relate to the preparation of the succinimide dispersant itself . Two-step methods are described, for example, in U.S. Patent Nos. 3,087,936; 3,172,892; And 3,272,746; The first step method is described in U.S. Patent Nos. 3,215,707, 3,231,587; 3,912,764; 4,110,349; And 4,234,435; Methods of heat treatment for preparing tetraethylenepentamine succinimide are described in U.S. Patent Nos. 3,361,673 and 3,401,118, and methods for preparing succinimides of halogenated alpha-olefin polymers are described in U.S. Patent 5,266,223; The free radical method is described in U.S. Patent 4,505,834; 4,749,505 and 4,863,623; Grafting methods are described in U.S. Patent Nos. 4,340,689; 4,670,515; 4,948,842; And 5,075,383.

The dispersing agent may also be post-treated in a conventional manner by reaction with any of a variety of agents. These include, but are not limited to, boron compounds such as boric acid, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehyde, ketone, carboxylic acid such as terephthalic acid, hydrocarbonsubstituted succinic anhydride, Phosphorus compounds. According to one embodiment, the post-treated dispersant is boronated.

Exemplary lubricating compositions are of the dispersant-free type, but according to one embodiment, only nitrogen-containing C3-C6 acylated polyalkylene compounds are used if a dispersant is substantially present. In particular, a succinimide dispersant is used which is derived from the reaction of an acylated C3-C6 polyalkylene compound with an amine to form succinic anhydride. It has been found that these small amounts of succinimide dispersants can be used without unduly affecting the spot rating. However, exemplary copolymers minimize or eliminate the need for such dispersants, because the copolymers have a beneficial effect on the dispersion of the oxidation product.

According to one embodiment, the dispersant is present in the lubricating composition in an amount of, for example, 0.01 to 2.5 wt%, 0.01 to 2 wt%, or 0.01 to 1.75 wt% or 0.01 to 1.5 wt%, or 0.5 to 2.5 wt%, or 0.5 to 1.75 wt% Or 0.5 to 1.5 wt%, and consists essentially of nitrogen-containing dispersants or dispersants derived from acylated C3-C6 polyalkylene compounds. Essentially, it is meant that the other dispersant is less than 0.2 wt%, less than 0.1 wt%, or less than 0.01 wt% of the lubricating composition. Gear oils produced with such low levels of dispersants are much more effective due to the presence of exemplary esterified copolymers.

According to one embodiment, the exemplary copolymer is substantially free of nitrogen as defined above, and the lubricating composition contains not more than 1.75 wt% of dispersant other than the exemplary copolymer.

2. Detergent

The lubricating composition optionally further comprises neutral or overbased detergents known in the art, such as those prepared by conventional methods known in the art. Suitable detergents include phenate, sulfofenate, sulfonate, salicylate, salicylate, carboxylic acid, phosphoric acid, alkylphenol, sulfur-coupled alkylphenol compounds and saligenin. The detergent may be present at 0 wt% to 1 wt%, 0.01 wt% to 1 wt%, 0.05 wt% to 0.75 wt%, or 0.1 wt% to 0.75 wt% of the lubricating composition.

3. Antioxidant

Antioxidant compounds useful in the present invention as antioxidants include oleyl sulfide, diphenylamine, phenyl-alpha-naphthylamine, hindered phenol, molybdenum dithiocarbamate, and mixtures and derivatives thereof. Antioxidant compounds may be used alone or in combination.

Exemplary diphenylamines include diarylamines such as alkylated diphenylamines.

Exemplary hindered phenol antioxidants may contain secondary butyl and / or tertiary butyl groups as steric hinders. The phenol group is often further substituted with a bridging group which binds to the hydrocarbyl group and / or the second aromatic group. Examples of suitable hindered phenol antioxidants include 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, Butyl-2,6-di-tert-butylphenol, 4-dodecyl-2,6-di-tert-butylphenol and mixtures thereof do. According to one embodiment, the hindered phenol antioxidant is an ester and may include, for example, Irganox (TM) L-135 (Ciba product). Suitable examples of molybdenum dithiocarbamates that can be used as antioxidants include R.T. Vanderbilt Co. Commercial products sold under the trade names Vanlube 822 ™ and Molyvan ™ A from Asahi Denka Kogyo KK and commercial products sold under the trade names Adeka Sakura-Lube ™ S-100, S-165 and S-600 from Asahi Denka Kogyo KK do.

The antioxidant (s) may be present in the lubricating composition at up to 2 wt%, up to 1.5 wt%, up to 1.0 wt%, or up to 0.7 wt%, such as at least 0.001 wt%, at least 0.01 wt% or at least 0.1 wt% have.

4. Viscosity index improver

Other viscosity index improvers other than exemplary copolymers include hydrogenated styrene-butadiene rubbers, ethylene-propylene copolymers, hydrogenated styrene-isoprene polymers, hydrogenated diene polymers, polyalkylstyrenes, polyolefins, polyalkyl (meth) And mixtures thereof. According to one embodiment, the viscosity index improver (polymeric thickener) is poly (meth) acrylate.

5. Antiwear agent

The lubricating composition optionally further comprises at least one antiwear agent.

Examples of suitable antiwear agents include oil soluble amine salts of phosphorus compounds, olefin sulfates, metal dihydrocarbyl dithiophosphates (e.g., zinc dialkyldithiophosphates), thiocarbamate-containing compounds such as thiocarbamate esters, Methyamide, thiocarbamic acid ether, alkylene-coupled thiocarbamate and bis (S-alkyldithiocarbamyl) disulfide.

According to one embodiment, the oil-soluble amine salt damping agent comprises an amine salt of phosphoric acid ester or a mixture thereof. The amine salts of phosphoric acid esters include phosphoric acid esters and amine salts thereof; Dialkyldithiophosphoric acid esters and amine salts thereof; Amine salts of phosphites; And amine salts of phosphorus-containing carboxylic acid esters, ethers and amides; And mixtures thereof. The amine salts of phosphoric acid esters may be used alone or in combination.

According to one embodiment, the amine salt of an oil-soluble phosphorus comprises a partial amine salt-partial metal salt compound or a mixture thereof. According to one embodiment, the phosphorus compound further comprises a sulfur atom in the molecule. According to one embodiment, the amine salt of the phosphorus compound is ashless, i.e., metal-free (before mixing with other components).

Amines that may be suitable for use as amine salts include primary amines, secondary amines, tertiary amines, and mixtures thereof. Amines include those having at least one hydrocarbyl group or, according to certain embodiments, having two or three hydrocarbyl groups. The hydrocarbyl group may contain from 2 to 30 carbon atoms or, according to other embodiments, from 8 to 26, from 10 to 20 or from 13 to 19 carbon atoms.

Primary amines include but are not limited to ethylamine, propylamine, butylamine, 2-ethylhexylamine, octylamine and dodecylamine, as well as fatty amines such as n-octylamine, Tetradecylamine, n-hexadecylamine, n-octadecylamine and oleylamine. Other useful fatty amines include commercially available fatty amines such as "Armeen (R)" amine (a product readily available from Akzo Chemicals (Chicago, Ill.)) Such as Armeen C, Armeen O, Armeen OL, Armeen T, Armeen HT , Armeen S and Armeen SD, wherein the letter is an indication of an aliphatic group such as a coco, oleyl, tallow or stearyl group.

Examples of suitable secondary amines include dimethylamine, diethylamine, dipropylamine, dibutylamine, diamylamine, dihexylamine, diheptylamine, methylethylamine, ethylbutylamine and ethylamylamine. The secondary amines can be cyclic amines such as piperidine, piperazine and morpholine.

In addition, the amine can be a tertiary aliphatic primary amine. In this case, the aliphatic group may be an alkyl group containing 2 to 30, 6 to 26 or 8 to 24 carbon atoms. Tertiary alkylamines include monoamines such as tert-butylamine, tert-hexylamine, 1-methyl-1-amino-cyclohexane, tert-octylamine, tert-decylamine, Decylamine, tert-hexadecylamine, tert-octadecylamine, tert-tetracosanylamine and tert-octacosylamine.

According to one embodiment, the acid amine salt of phosphorus comprises an amine having a C ₁₁ to C ₁₄ tertiary alkyl primary or a mixture thereof. According to one embodiment, the acid amine salt of phosphorus is C ₁₄ To _C18 tertiary alkyl primary amines or mixtures thereof. According to one embodiment, the acid amine salt of phosphorus comprises an amine having a C ₁₈ to C ₂₂ tertiary alkyl primary amine or a mixture thereof.

Mixtures of amines may also be used in the present invention. According to one embodiment, useful mixtures of amines are "Primene® 81R" and "Primene® JMT". Primene® 81R and Primene® JMT (both produced and sold by Rohm and Haas) contain a mixture of C ₁₁ to C ₁₄ tertiary alkyl primary amines and a mixture of C ₁₈ to C ₂₂ tertiary alkyl primary amines to be.

According to one embodiment, an oil soluble amine salt of a phosphorus compound is prepared by reacting an amine with (i) a hydroxy-substituted diester of phosphoric acid, or (ii) phosphorylated hydroxy-substituted di- or tri-ester of phosphoric acid / RTI &gt; of a phosphorus-containing compound that can be obtained / obtained by a process comprising the steps of: A more detailed description of this class of compounds is disclosed in U.S. Publication No. 2008/0182770.

According to one embodiment, the hydrocarbylamine salt of the alkylphosphoric ester is a mixture of Primene 81R (product produced and sold by Rohm & Haas) which is a mixture of C ₁₁ to C ₁₄ tertiary alkyl primary amines and C ₁₄ to C ₁₈ alkylated Phosphoric acid.

Examples of hydrocarbylamine salts of dialkyldithiophosphate esters include isopropyl, methyl-amyl (4-methyl-2-pentyl or mixtures thereof), 2-ethylhexyl, heptyl, octyl or nonyldithioic acid and ethylenediamine, (S) with polyamine or Primene 81R (TM) and mixtures thereof.

According to one embodiment, the dithioic acid can react with epoxides or glycols. The reaction product further reacts with an acid, anhydride or lower ester of phosphorus. The epoxide comprises an aliphatic epoxide or styrene oxide. Examples of useful epoxides include ethylene oxide, propylene oxide, butene oxide, octene oxide, dodecene oxide and styrene oxide. According to one embodiment, the epoxide is propylene oxide. The glycol may be an aliphatic glycol having 1 to 12, 2 to 6, or 2 to 3 carbon atoms. Dithiophosphoric acids, glycols, epoxides, inorganic reagents and methods for making them are described in U.S. Patent Nos. 3,197,405 and 3,544,465. The resulting acid may then be converted to a salt by an amine. One example of a suitable dithiophosphoric acid is a mixture of 1.3 moles of hydroxypropyl O, O-di (4-methyl-2-pentyl) phosphorodithioate (di (Prepared by reacting propylene oxide at 25 캜) with phosphorus pentoxide (about 64 g) at 58 캜 over 45 minutes. The mixture is heated at 75 占 폚 for 2.5 hours, mixed with diatomaceous earth and filtered at 70 占 폚. The filtrate contained 15.2 wt% sulfur with an acid value of 87 (bromophenol blue), which was 11.8 wt%.

The dithiocarbamate-containing compound can be prepared by reacting a dithiocarbamate acid or salt with an unsaturated compound. The dithiocarbamate-containing compound may also be produced by simultaneously reacting an amine, a disulfide carbon and an unsaturated compound. Generally, the reaction takes place at a temperature of from 25 캜 to 125 캜.

Examples of suitable olefins that can be sulfided with sulfurized olefins include but are not limited to propylene, butylene, isobutylene, pentene, hexane, heptene, octane, nonene, decene, undecene, dodecene, undecyl, tridecene, , Hexadecene, heptadecene, octadecene, nonodecene, eicosene, and mixtures thereof. Hexadecene, heptadecene, octadecene, nonodecene, eicosene and mixtures thereof and their dimers, trimers and tetramers are particularly useful olefins. Alternatively, the olefin can be a Diels-Alder addition product of a diene, such as 1,3-butadiene and an unsaturated ester, such as butyl acrylate.

Another class of sulfurized olefins includes fatty acids and esters thereof. Fatty acids are often obtained from plant oils or animal oils and usually contain from 4 to 22 carbon atoms. Examples of suitable fatty acids and esters thereof include triglycerides, oleic acid, linoleic acid, palmitoleic acid and mixtures thereof. Fatty acids may be obtained from rad oil, tall oil, peanut oil, soybean oil, cottonseed oil, sunflower oil and mixtures thereof. According to one embodiment, the fatty acid and / or ester is mixed with the olefin.

According to an alternative embodiment, the ashless wear resistant agent may be a monoester of an acid containing a polyol and an aliphatic carboxylic acid, often 12 to 24 carbon atoms. Often, the monoester of the polyol and aliphatic carboxylic acid is in the form of a mixture with sunflower seed oil and the like, which comprises from 5 to 95% by weight, in some embodiments from 10 to 90% by weight, from 20 to 85% by weight, To 80% by weight of the composition. Aliphatic carboxylic acids (especially monocarboxylic acids) that form esters are generally acids containing 12 to 24, or 14 to 20 carbon atoms. Examples of carboxylic acids include dodecanoic acid, stearic acid, lauric acid, behenic acid and oleic acid.

The polyols include diols, triols, and alcohols having a greater number of alcoholic OH groups. Polyhydric alcohols include ethylene glycols such as di-, tri- and tetraethylene glycols; Propylene glycols such as di-, tri- and tetrapropylene glycol; Glycerol; Butanediol; Hexanediol; Sorbitol; Arabitol; Mannitol; Sucrose; Fructose; Glucot and pentaerythritol, such as di- and tripentaerythritol. The polyol may be diethylene glycol, triethylene glycol, glycerol, sorbitol, pentaerythritol, dipentaerythritol or a mixture thereof.

Commercially available monoesters known as "glycerol monooleate " include glycerol monooleate, glycerol monooleate, 35 ± 5% glycerol diolate, and oleic acid, &Lt; / RTI &gt; The amount of monoester described above is calculated on the basis of the actual correct amount of polyol monoester present in any such mixture.

The wear-resistant agent (s) may be present from 0.0 wt% to 5 wt% or 0.5 wt% to 5 wt%, 0.5 wt% to 3 wt%, or 1 wt% to 2 wt% of the lubricating composition.

6. Scuffing agent

In addition, the lubricating composition may contain anti-scarring agents. Anti-scuffing compounds are believed to reduce adhesive wear and are often sulfur compounds. Typically, the sulfur compound is selected from the group consisting of sulfurized olefins, organic sulfides and polysulfides such as dibenzyl disulfide, bis- (chlorobenzyl) disulfide, dibutyl tetrasulfide, di-tertbutyl polysulfide, sulfurized methyl ester of oleic acid, Sulfide dipentene, sulfurized terpene, sulfurized Diels-Alder addition product, alkylsulphenyl N'N-dialkyldithiocarbamate, reaction product of polybasic acid ester and polyamine, 2,3-dibromopropoxyisobutyric acid , The acetoxy methyl esters of dialkyldithiocarbamic acid and the acyloxyalkyl ethers of xanthogen, and mixtures thereof.

The anti-scuffing agent (s) may be present from 0 wt% to 6 wt%, 1 wt% to 6 wt% or 3 wt% to 6 wt% of the lubricating composition.

7. Extreme pressure

Extreme pressure (EP) agents soluble in oils include sulfur and chlorosulfur-containing EP agents, chlorinated hydrocarbon EP agents and phosphorus EP agents. Examples of such EP agents include chlorinated waxes; But are not limited to, sulfurized olefins (e.g., sulfobutyl isobutylene), organic sulfides and polysulfides such as dibenzyl disulfide, bis- (chlorobenzyl) disulfide, dibutyl tetrasulfide, methyl sulfide esters of oleic acid, , Dipentene sulfide, terpene sulphide and sulfurized Diels-Alder addition products; Phosphorus sulfided hydrocarbons such as the reaction product of phosphorus sulfide and terpentine or methyl oleate; In esters such as hydrocarbyl phosphates and trihydrocarbon phosphates such as dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentyl phenyl phosphite; Diphenylphenyl phosphite, tridecyl phosphite, distearyl phosphite and polypropylene substituted phenol phosphite; Metal thiocarbamates such as zinc dioctyldithiocarbamate and barium heptylphenol dic acid; An amine salt of a reaction product obtained by reacting an amine salt or derivative of an alkylphosphoric acid or a dialkylphosphoric acid such as dialkyldithioic acid with propylene oxide followed by further reaction with P ₂ O ₅ ; And mixtures thereof (such as those described in U.S. Patent 3,197,405).

Suitable dimercaptothiadiazoles include hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazoles and unsubstituted equivalents thereof, which are added to a nonpolar medium such as oil of lubricating viscosity Lt; 0 &gt; C. The total number of carbon atoms in the hydrocarbyl-substituents that tend to promote solubility will generally be at least 8, or at least 10, or at least 12. If the thiadiazole has two or more hydrocarbyl groups, then the number of carbon atoms per group may be less than 8, with the proviso that the total number of carbons is not less than 8.

Examples of dimercaptothiadiazole include 2,5- (tert-octyldithio) -1,3,4-thiadiazole, 2,5- (tert-nonyldithio) -1,3,4-thiadiazole Sol, 2,5- (tert-decyldithio) -1,3,4-thiadiazole, 2,5- (tert-undecyldithio) -1,3,4-thiadiazole, 2,5 - (tert-dodecyldithio) -1,3,4-thiadiazole, 2,5- (tert-tridecyldithio) -1,3,4-thiadiazole, 2,5- Tetradecyldithio) -1,3,4-thiadiazole, 2,5- (tert-pentadecyldithio) -1,3,4-thiadiazole, 2,5- (tert-hexadecyldithio ) -1,3,4-thiadiazole, 2,5- (tert-heptadecyldithio) -1,3,4-thiadiazole, 2,5- (tert- Thiadiazole, 2,5- (tert-nonadecyldithio) -1,3,4-thiadiazole or 2,5- (tert-eicosyldithio) -1,3,4- Thiadiazoles and oligomers and mixtures thereof. According to one embodiment, the dimercaptothiadiazole comprises 2,5-dimercapto-1,3,4-thiadiazole.

Dimercaptothiadiazole is derived from 2,5-dimercapto-1,3,4-thiadiazole or hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazole or oligomers thereof . Oligomers of hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazoles generally have a sulfur-sulfur bond between 2,5-dimercapto-1,3,4-thiadiazole units To form oligomers of two or more thiadiazole units. According to one embodiment, the dimercaptothiadiazole (generally 2,5-dimercapto-1,3,4-thiadiazole) is formed by reacting an ethylenically unsaturated amide or ester with dimercaptothiadiazole . Amides or esters can be selected from the group consisting of hydrocarbyl- (meth) acrylates or hydrocarbyl- (meth) acrylamides, hydrocarbyl-substituted acrylates, hydrocarbyl-substituted crotonates, hydrocarbyl- Mate, or mixtures thereof.

According to one embodiment, the dimercaptothiadiazole (typically 2,5-dimercapto-1,3,4-thiadiazole) may be a compound represented by the formula:

In this equation,

R ₁ can be an alkylene group containing 1 to 5, 1 to 3 or 2 carbon atoms;

R ₂ can be a hydrocarbyl group containing 1 to 16, 2 to 8 or 4 carbon atoms;

Y may be -O- or > NR ₃ (typically Y may be -O-);

R ₃ can be hydrogen or R ₂ .

The dimercaptothiadiazole of the above formula may be prepared by reacting a suitable hydrocarbyl- (meth) acrylate or hydrocarbyl- (meth) acrylamide with 2,5-dimercapto-1,3,4-thiadiazole can do. The reaction of hydrocarbyl- (meth) acrylate or hydrocarbyl- (meth) acrylamide with 2,5-dimercapto-1,3,4-thiadiazole is carried out at a temperature of from 50 ° C to 150 ° C, from 70 ° C to 120 ° C , Or at a temperature ranging from 80 &lt; 0 &gt; C to 100 &lt; 0 &gt; C.

According to one embodiment, a dimercaptothiadiazole salt (typically a 2,5-dimercapto-1,3,4-thiadiazole salt) can be prepared by reacting dimercaptothiadiazole with an epoxide.

The EP agent may be present at 0 wt% to 6 wt%, 1 wt% to 6 wt%, 2 wt% to 6 wt% or 3 wt% to 6 wt% of the lubricating composition.

8. Corrosion inhibitor, foam inhibitor, pour point depressant, friction modifier

Corrosion inhibitors that may be useful include fatty amines, octylamine octanoate and dodecenyl succinic acid or anhydrides and condensation products of fatty acids and polyamines such as oleic acid.

The corrosion inhibitor (s) may be present from 0 wt% to 3 wt%, 0.01 wt% to 3 wt%, or 0.01 wt% to 1 wt% of the lubricating composition.

Foam inhibitors that may be useful in exemplary compositions include silicone; A copolymer of ethyl acrylate and 2-ethylhexyl acrylate (which may optionally further comprise vinyl acetate); And anti-emulsifiers such as trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene oxides and (ethylene oxide-propylene oxide) polymers.

Pour point depressants that may be useful in exemplary compositions include polyalphaolefins, esters of maleic anhydride-styrene copolymers and poly (meth) acrylates, polyacrylates and polyacrylamides such as polyalkyl methacrylates .

Friction modifiers that may be useful in the exemplary compositions include fatty acid derivatives such as amines, esters, epoxides, fatty imidazolines, condensation products of carboxylic acids and polyalkylene-polyamines, and amine salts of alkylphosphoric acids.

Examples of suitable friction modifiers include long chain fatty acid derivatives of amines, long chain fatty esters, or derivatives of long chain fatty epoxides; Fatty imidazolines, such as condensation products of carboxylic acids and polyalkylene-polyamines; Amine salts of alkylphosphoric acids; Fatty alkyl tartrates; Fatty alkyltartramides; Fatty alkyltartramides; Fatty glycolate; Fatty glycolamide fatty phosphonates; Fatty phosphite; Borated phospholipids, borated fatty epoxides; Glycerol esters; Borated glycerol esters; Fatty amines; Alkoxylated fatty amines; Borated alkoxylated fatty amines; Hydroxy and polyhydroxy fatty amines such as tertiary hydroxy fatty amines; Hydroxyalkyl amides; Metal salts of fatty acids; Metal salts of alkyl salicylates; Fatty oxazoline; Fatty ethoxylated alcohols; A condensation product of a carboxylic acid and a polyalkylene polyamine; Or a reaction product of a fatty carboxylic acid with guanidine, aminoguanidine, urea or thiourea and salts thereof. As used herein, the term "fatty alkyl or fat " in relation to friction modifiers refers to carbon chains, typically straight chain carbon chains, having from 10 to 22 carbon atoms. The friction modifier also includes materials such as sulfurized fatty compounds and monoesters of aliphatic carboxylic acids and polyols, which may or may not be derived from olefins, molybdenum dialkyldithiophosphates, molybdenum ditacarbamates, and sunflower seed oil or soybean oil You may.

According to one embodiment, the friction modifier may be a long chain fatty acid ester. According to another embodiment, the long chain fatty acid ester may be a monoester, and according to another embodiment, the long chain fatty acid ester may be (tri) glyceride.

The friction modifier may be selected from the group consisting of 0wt% to 7wt%, 0.1wt% to 6wt%, 0.25wt% to 3.5wt%, 0.5wt% to 2.5wt%, 1wt% to 2.5wt%, 0.05wt% to 0.5wt% 5 to 7 wt%.

If, in addition to the dispersing agent, any performance additives used in the lubricating composition act as a dispersant of the oxidized product, the additive may be selected so that the sum of all dispersants is less than 2 wt%, less than 1.5 wt%, less than 1 wt% wt% or less, or 0.2 wt% or less.

III. Industrial availability

The method and exemplary lubricating composition may be suitable for cooling lubricants, greases, gear oils, axle oils, drive shaft oils, traction oils, manual transmission oils, automatic transmission oils, metalworking fluids, hydraulic oils or internal combustion engine oils. The exemplary lubricating composition can be fed to a mechanical device, such as a gear or transmission system, without the addition of any additional dispersing agent, and can be used for lubrication during normal operation of the mechanical device.

According to one embodiment, the method and exemplary lubricating composition may be suitable for at least one of gear oil, axle oil, drive shaft oil, traction oil, manual transmission oil and automatic transmission oil.

As an example, the exemplary lubricating composition has utility as a gear oil.

Exemplary copolymers may also be used in an automatic transmission system such as a continuously variable transmission (CVT), an infinitely variable transmission (IVT), a toroidal transmission, a continuous sleeping torque converter clutch (CSTCC), a stepped automatic transmission or a dual clutch transmission There may be the availability of.

The applications described herein (which may also be referred to as methods) and lubricating compositions can provide lubricants with acceptable / improved dispersibility properties (cleanliness) and oxidation control, and can also provide acceptable or improved shear stability, acceptable Or to provide one (or at least two, or all) of an improved viscosity index control, and an acceptable or improved low temperature viscosity.

According to various embodiments, suitable lubricating compositions include copolymers (based on the active material) that are present in the ranges as shown in Table 1.

Modes (wt% of lubricating composition) A B C Exemplary copolymers 5-95 30-60 40-50 Other performance additives 0-20 0.5-20 0.5-15 Oil of lubricating viscosity 0.01-95 20-69.5 35-59.5 Sum of three components 100 100 100

Unexpectedly, exemplary copolymer-containing fluids have been found to disperse oxidation by-products without the use of additional dispersants. The lubricating composition has been found to exhibit improvements associated with this by reducing or eliminating dispersants.

The following examples illustrate the invention. These embodiments are non-exclusive and are not intended to limit the scope of the invention.

Example

Example 1: Amine- capped Preparation of Esterified Copolymer (Copolymer 1)

A 5L reaction flask was charged with 407.8 grams of maleic anhydride (MAA), 700 grams of 1-dodecene, and 1108 grams of toluene. The molar ratio of 1-dodecene: maleic anhydride was 1: 1. The flask was fitted with a PTFE gasket and a 5-port flange lid was fitted with an overhead stirrer, stirrer guide, thermocouple, nitrogen inlet (250 cm3 / min nitrogen), silicone bulkhead with peristaltic pump via cannula and water condenser . The reaction flask and its contents were heated to 108 占 폚.

A mixture of 35.98 g of Trigonox® 21S (tert-butylperoxy-2-ethylhexanoate initiator available from Akzo Nobel), 26.94 g of n-dodecylmercaptan and 485 g of toluene was mixed together and charged to the reaction flask via a peristaltic pump 240 Min. The reaction mixture was stirred at 108 DEG C for several hours. The reaction flask was equipped with a Dean-Stark trap and the reaction mixture was heated to 120 DEG C with stirring. 618.1 g of Alfol 810 ™ using a peristaltic pump was added over 45 minutes and the resulting reaction mixture was stirred for 1 hour. An additional 618 g of Alfol 810 &lt; TM &gt; and 28.55 g of 70% methanesulfonic acid in water were added to the reaction flask for 3 to 4 hours while the reaction temperature was gradually increased to 135 &lt; 0 &gt; C. The reaction mixture was then heated to 145 DEG C and 70 g of n-butanol and 14.27 g of 70% methanesulfonic acid aqueous solution were added and stirred for 1 hour. An additional 70 g of n-butanol was added and the reaction was stirred for 2 hours. The addition of n-butanol lasted until more than 97% of the 1-dodecene: maleic anhydride copolymer was esterified. Sufficient sodium hydroxide (50% aqueous sodium hydroxide solution) was added to quench methanesulfonic acid and the mixture was stirred for 1 hour before adding 47.98 g of 4- (3-aminopropyl) morpholine and stirring for an additional 2 hours did. The reaction flask was mounted for vacuum stripping and the final product was vacuum stripped at 150 ° C (-28 in Hg) and held for 2.5 hours. The vacuum was removed and the flask was cooled to 120 &lt; 0 &gt; C. The resulting reaction mixture was filtered using fax-5 and filter cloth.

The product analysis showed a nitrogen content of 0.103 wt%. The kinematic viscosity (KV100) at 100 DEG C measured by ASTM method D455 was 288 cSt and the TAN was 4.5 mg KOH / g. The TAN was the total acid number and was measured by 0.1 M KOH titration with phenolphthalein indicator in toluene / isopropanol / water (500: 495: 5) and measured in mg KOH / g.

GPC experiments on tetrahydrofuran for polystyrene standards showed M _w 16,400, M _n 7900 and PDI (Mw / Mn) 2.06 for the esterified amine-capped copolymer.

Example 2: Amine- capped Preparation of Esterified Copolymer (Copolymer 2)

The same procedure as used in Example 1 was followed except that the copolymer of 1-dodecene: maleic anhydride prepared in Example 1 was esterified with a mixture of 84.4% by weight of Alfol 810 ™ and 15.6% by weight of Isofol 16 ™, Amine end capping of the copolymer was carried out with n-butyl amine.

The product analysis showed a nitrogen content of 0.23 wt%, and the kinematic viscosity (KV 100) at 100 ° C measured by ASTM method D445 was 390 cSt. And the TAN was 3.3 mg KOH / g.

GPC experiments conducted on tetrahydrofuran for the polystyrene standards showed M _w 16,448, M _n 7,300 and PDI 2.25 for the esterified, amine-capped copolymer.

Example 3: Preparation of an amine cap- free esterified copolymer (Copolymer 3)

A procedure analogous to that used in Example 1, except that the copolymer of 1-dodecene: maleic anhydride prepared in Example 1 was esterified with a mixture of Alfol 810 ™ and Isofol 16 ™ in a ratio of 9: 1 by weight, . After esterification with Alfol 810 ™ and Isofol 16 ™, the esterification of the copolymer was completed with n-butanol as described in Example 1. Amine end capping of the esterified copolymer was not performed.

The product analysis showed 248 cSt at 100 占 폚 (KV100) as measured by ASTM D445 method and 6.3 mg KOH / g of TAN.

GPC experiments performed on tetrahydrofuran for polystyrene standards showed M _w 13,177, M _n 6549 and PDI 2.01 for the esterified copolymer.

Example 4: Amine- capped Preparation of Esterified Copolymer (Copolymer 4)

A procedure analogous to that used in Example 1, except that the copolymer of 1-dodecene: maleic anhydride prepared in Example 1 was esterified with a mixture of Alfol 810 ™ and Isofol 16 ™ in a ratio of 9: 1 by weight, . After esterification with Alfol 810 ™ and Isofol 16 ™, the esterification of the copolymer was completed with n-butanol as described in Example 1, and the amine endcapping of the esterified copolymer was carried out with aminoethylethylene urea did.

The product analysis had a nitrogen content of 0.14 wt%, a kinematic viscosity at 100 DEG C (KV100) of 211.3 cSt measured by ASTM D445 method. And a TAN of 3.3 mg KOH / g.

Example 5: Preparation of lubricating composition

Lubricating compositions A, B, and C (COMP.A, COMP.B and COMP.C) were prepared as described in Table 2 using an amine-capped esterified copolymer (copolymer 2) prepared according to Example 2 Manufactured together. All amounts are wt%. The components of the performance package (dispersant free) are shown in Table 3 and shown on an oil-free basis. Compositions D, E and F (COMP.D, COMP.E and COMP.F, respectively) were prepared with the esterified copolymer (copolymer 3) prepared according to Example 3. All amounts are wt%.

It should be noted that the actual amount of dispersant in the composition is only 67% of that shown in Table 2 because this dispersant is diluted with 33 wt% mineral oil. Thus, the maximum amount of dispersant used in these experiments was about 1.5 wt%.

Existing amount wt% Explanation function 22.7 Phosphoric ester / amine salt Abrasion 41.0 Sulfided olefin Extreme pressure 19.6 Isobutylene sulfide Extreme pressure 0.12 Alkenylamide Friction modifier 5.07 Defoamer and corrosion inhibitor Defoamer and corrosion inhibitor Remaining amount Diluted oil (Group III, 4cSt)

Oxidation stability test

Compositions A, B, C and D were oxidized using CEC L-48-00 Procedure B, where air passed through 100 ml oil at a rate of 5 liters / hr for 192 hours at 160 占 폚. The results are shown in Table 4, expressed as the rate of increase in kinematic viscosity at 40 占 폚 (KV 40%) and 100 占 폚. In addition, the inspection procedure measures the tube grade and the dispersibility grade is calculated (as described above). For spot ratings, the higher the value, the better the result.

The kinematic viscosity was measured at 100 占 폚 (KV100) and 40 占 폚 (KV40) according to ASTM D445.

The viscosity index (VI) was measured according to ASTM D2270.

¹ Viscosity at the start of the test

COMP. A, COMP. B and COMP. The DKA results of C show that as the dispersant concentration decreases, a higher dispersant spot rating is achieved at the same tube grade at approximately the same viscosity. Although the DKA results of COMP.D indicate higher oxidation of the oil (i. E., Higher TAN change and higher KV100), the spot rating indicates that even though the oxidation product is a non-amine capped copolymer, 3 &lt; / RTI &gt; (Example 3).

Example 6: Comparison with lubricating compositions containing other viscosity index improvers

Other lubricity compositions containing viscosity index improvers were also investigated to determine whether they would produce such unexpected results. The compositions tested are shown in Table 5. Exemplary Copolymers, Copolymer 1 (Example 1) and Copolymer 4 (Example 4) were prepared to prepare compositions G, H and J (Example 1) and compositions K, L and M (Example 4) Used. Comparative compositions N, O and P were prepared using poly alpha olefin (PAO 100), a Group IV base oil, and poly (alkyl methacrylate) (PMA) was used in the preparation of comparative compositions Q and R. The dispersant, if used, was a borated polyisobutylene succinimide dispersant. The same performance package as described in Table 3 was used. The results are shown in Table 6.

The results show that, as the dispersant level change is evidenced by the spot rating, it does not provide any dispersive change to the PMA bulk fluid. PAO100 shows a reasonable improvement in spot rating, but the result is much lower than the spot rating achieved by exemplary copolymerization (i.e., not allowed for some applications). Exemplary copolymer 1 exhibits an improvement in spot grade and an increase in viscosity at equivalent CEC Tube grade (3). The results imply that the exemplary copolymers can completely disperse the oxidation product without the addition of additional dispersants. The results also suggest that PAO100 can not achieve these results in the presence or absence of dispersants and PMA exhibits more substantial viscosity increases, tube grades and incomplete dispersibility under the same conditions.

Each of the foregoing documents is incorporated herein by reference. It is to be understood that all numerical quantities embodying herein, including amounts of materials, reaction conditions, molecular weights, number of carbon atoms, etc., unless the context clearly dictates otherwise. Unless otherwise indicated, each chemical or composition referred to herein is to be understood as being a commercial grade substance that may contain isomers, by-products, derivatives and other substances commonly known to be present in commercial grades. However, the amount of each chemical component is the amount excluding any solvent or diluting oil that may normally be present in a commercially available material, unless otherwise indicated. It is to be understood that the amounts, ranges, and upper and lower limits of limits set forth herein can be combined independently. Likewise, the ranges and amounts of each component of the present invention may be used with ranges or amounts of any other component.

As used herein, the expression "consisting essentially of" allows inclusion of a substance that does not materially affect the basic properties and novel properties of the composition under consideration. As used herein, any member of the genus (or list) may be excluded from the claims.

As used herein, the term "(meth) acryl" and related terms include both acrylic and methacrylic groups.

As used herein, the term "branched primary alcohol at [beta] -or higher position (s)" refers to a branched primary alcohol in 2- or more positions (e.g., 3-, 4-, 5-, 6- or 7- It means alcohol with branching.

As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its conventional meaning as known to those skilled in the art. Specifically, it means a group in which a carbon atom is directly attached to the remainder of the molecule and shows mainly hydrocarbon characteristics. Examples of hydrocarbyl groups include the following:

a. Alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-substituted aromatic substituents, as well as other moieties of the molecule (E.g., two substituents together form a ring);

b. Substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups that do not alter the predominantly hydrocarbon nature of the substituents in the context of the present invention (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto , Nitro, nitroso and sulfoxy);

c. Heterocyclic substituents, that is, substituents containing, apart from carbon, a ring or chain composed of carbon atoms, while retaining predominantly hydrocarbon character in the context of the present invention; And

d. Hetero atoms include sulfur, oxygen and nitrogen and include substituents such as pyridyl, furyl, thienyl and imidazolyl. Generally, no more than two non-hydrocarbon substituents, and in one aspect less than one, will be present on every ten carbon atoms of the hydrocarbyl group; Typically, no hydrocarbyl substituent will be present in the hydrocarbyl group.

While the present invention has been described with reference to preferred embodiments thereof, it is to be understood that various modifications thereof will be apparent to those skilled in the art upon reading this specification. Accordingly, the invention disclosed herein is to be understood as embracing such modifications as fall within the scope of the following claims.

It will be appreciated that the features and functions disclosed herein, as well as variations of other features and functions, or alternatives thereof, may be combined into many other systems or apparatus. Various alternatives, modifications, variations, or improvements that are presently unexpected or unexpected may be subsequently made by those skilled in the art and are also considered to be within the scope of the following claims.

Claims (42)

a) an esterified copolymer having a main chain containing a unit derived from a vinyl aliphatic monomer and a unit derived from a carboxylic acid monomer, wherein the carboxylic acid monomer contains an?,? - ethylenically unsaturated dicarboxylic acid or a derivative thereof;
b) a lubricating composition containing an oil of lubricating viscosity,
Wherein the lubricant composition contains not more than 2.5% by weight of a dispersant other than the esterified copolymer for dispersion of the oxidation product. The lubricating composition of claim 1 wherein the lubricant composition comprises not more than 2 wt%, not more than 1.75 wt%, not more than 1.5 wt%, not more than 1 wt%, not more than 0.5 wt%, not more than 0.2 wt% or not more than 0.1 wt% &Lt; / RTI &gt; The lubricating composition of claim 1 or 2, wherein the lubricating composition comprises 0.01 to 2.5 wt%, 0.01 to 2 wt%, 0.01 to 1.75 wt%, 0.01 to 1.5 wt%, 0.5 to 2.5 wt%, 0.5 To 1.75 wt% or 0.5 to 1.5 wt%. 4. Lubricating composition according to any one of claims 1 to 3, consisting essentially of a nitrogen-containing dispersant in the presence of a dispersing agent and derived from an acylated C3-C6 polyalkylene compound. 5. A lubricating composition according to any one of claims 1 to 4, wherein the esterified copolymer contains nitrogen-containing groups. 6. The lubricating composition according to any one of claims 1 to 5, wherein at least a part of units derived from a carboxylic acid monomer is at least one of aminated with an nitrogen-containing compound, amidated and imidized. 7. The method of claim 6, wherein the nitrogen-containing compound is selected from the group consisting of an amine-amine compound selected from the group consisting of morpholine, imidazolidinone, aminoamide,? -Alanine alkyl ester, aliphatic amine, aromatic amine, aliphatic polyamine, aromatic polyamine, Containing compound. 8. The method according to claim 6 or 7, wherein 0.1 to 25% of the carboxylic acid functional group possessed by the unit derived from the carboxylic acid monomer is aminated with the nitrogen-containing compound, at least one of the amidated and imidized Lubricating composition. 9. The lubricating composition according to any one of claims 6 to 8, wherein at least 1% of the carboxylic acid functional groups present in the unit derived from the carboxylic acid monomer react with the nitrogen-containing compound to provide a nitrogen-containing group. 4. The lubricating composition according to any one of claims 1 to 3, wherein the esterified copolymer is substantially free of nitrogen-containing groups. 11. A lubricating composition according to claim 10, wherein the lubricating composition contains not more than 2 wt% of a dispersant other than the exemplary copolymer. 12. The lubricating composition according to any one of claims 1 to 11, wherein the esterified copolymer has a weight average molecular weight of from 5,000 to 25,000. 13. The lubricating composition according to any one of claims 1 to 12, wherein the esterified copolymer has a weight average molecular weight of from 5000 to 10,000, from 15,000 to 25,000, or from 10,000 to 17,000. 14. The lubricating composition according to any one of claims 1 to 13, wherein the esterified copolymer is at least 5 wt% of the lubricating composition. 15. Lubricating composition according to any one of claims 1 to 14, wherein the esterified copolymer is at least 10 wt%, at least 40 wt% or at least 60 wt% of the lubricating composition. 16. Lubricating composition according to any one of claims 1 to 15, wherein the esterified copolymer is 30 to 60 wt% or 40 to 50 wt% of the lubricating composition. 17. The lubricating composition according to any one of claims 1 to 16, wherein the oil of lubricating viscosity is at least 20 wt% or at least 30 wt% of the lubricating composition. 18. The lubricating composition according to any one of claims 1 to 17, wherein the copolymer is esterified with a primary alcohol. 19. The lubricating composition of claim 18, wherein the primary alcohol contains a primary alcohol branched at &lt; RTI ID = 0.0 &gt; 1- or &lt; / RTI &gt; 20. The lubricating composition according to claim 18 or 19, wherein the primary alcohol further comprises a linear primary alcohol. 21. A lubricating composition according to any one of claims 18 to 20, wherein the primary alcohol contains at least 6 carbon atoms. 22. The lubricating composition according to any one of claims 1 to 21, wherein the carboxylic acid monomer contains maleic anhydride. 22. The composition of any one of claims 1 to 22, wherein the vinyl aliphatic monomer contains an alpha-olefin. 24. The lubricating composition of claim 23, wherein the alpha-olefin contains at least six carbon atoms. 25. The composition of any one of claims 1 to 24, wherein the molar ratio of vinyl aliphatic monomer units to carboxylic acid monomer units present in the copolymer is from 1: 3 to 3: 1, from 0.6: 1 to 1.2: 1, or from 0.7: 1: &lt; / RTI &gt; 1.1. 26. The lubricating composition according to any one of claims 1 to 25, wherein the esterified copolymer backbone further comprises units derived from vinyl aromatic monomers. 27. The lubricating composition of claim 26, wherein the molar ratio of units derived from vinyl aromatic monomers to units derived from vinyl aliphatic monomers is 0: 100 to 25:75, or 10:90 or less. 28. The lubricating composition according to any one of claims 1 to 27, wherein the copolymer backbone contains 20 or more units or 100 or more units. 29. The lubricating composition according to any one of claims 1 to 28, wherein the copolymer backbone contains vinyl aliphatic monomers and units derived from carboxylic acid monomers of up to 1000 or up to 500 or up to 250 up. 30. Lubricating composition according to any one of claims 1 to 29, further comprising at least one performance additive other than the esterified copolymer. 32. The composition of claim 30, wherein the at least one other performance additive is selected from the group consisting of metal deactivators, detergents, viscosity index improvers, friction modifiers, corrosion inhibitors, antiwear agents, extreme pressure agents, antiscuffing agents, antioxidants, A seal expander, and a mixture thereof. 32. The method of claim 31 wherein at least one other performance additive is selected from the group consisting of dimercapto-1,3,4-thiadiazole, derivatives of dimercapto-1,3,4-thiadiazole, sulfurized olefins, A lubricating composition comprising a selected extreme pressure agent. 33. A process according to any preceding claim wherein the lubricating composition is selected from the group consisting of N-substituted long chain alkenyl succinimides, polyisobutylene succinimides complexed with zinc, Mannich bases, Less than 1.75 wt%, less than 1.5 wt%, less than 1 wt%, less than 0.5 wt%, or less than 0.2 wt%, based on the total weight of the lubricant composition. 34. The lubricating composition according to any one of claims 1 to 33, wherein the 20 hr KRL SSI of the lubricating composition is 0 to 30, 0 to 10 or 10 to 30. (A) A method for producing a copolymer comprising the steps of: (1) preparing a copolymer comprising (1) (1) (i) a vinyl aliphatic monomer and (ii) a carboxylic acid monomer having an?,? Ethylenically unsaturated dicarboxylic acid or a derivative thereof,
(2) optionally, esterifying the copolymer of step (1) to form an esterified copolymer,
(3) optionally, reacting the copolymer of step (1) or (2) with a nitrogen-containing compound in an amount to provide an esterified copolymer having at least 0.01 wt% nitrogen, Wherein the copolymer is esterified in at least one of (1), (2) and (3); And
(B) mixing the esterified copolymer formed in (A) with at least one of a lubricating viscosity oil and other performance additives besides the esterified copolymer to form a dispersion composition for dispersing the oxidation product other than the esterified copolymer Providing a lubricant composition containing up to 2.5 wt% of a dispersant. 36. The method of claim 35, comprising the step (3). The method of claim 35 or 36, wherein the reaction of the esterified copolymer of step (1) or (2) with the nitrogen-containing compound comprises from 0.01 wt% to 1.5 wt%, from 0.02 wt% to 0.75 wt% RTI ID = 0.0 &gt;% &lt; / RTI &gt; to 0.25 wt.% Nitrogen. 37. The process of any one of claims 35 to 37, comprising the step (2). 39. A process according to any one of claims 35 to 38, wherein the carboxylic acid monomer retains an ester group derived from a primary alcohol to provide an esterified copolymer in step (1). A lubricating composition formed by the method according to any one of claims 35 to 39. Use of the lubricating composition according to any one of claims 1 to 34 and 40, which is used in the motor vehicle powertrain system without the addition of any additional dispersing agent. 41. A method for lubricating a component of a power transmission system, comprising: supplying a lubricating composition according to any one of claims 1 to 34 to a component of a powertrain system of a vehicle.