GB2127418A - Lubricating oil containing hydroperoxidized ethylene copolymers and terpolymers as dispersants and v.i. improvers - Google Patents

Abstract

Lubricating oil compositions contain a multi-functional additive which is a hydroperoxidized, ethylene copolymer or terpolymer having an excess of carboxylic acid to hydroxy groups and prepared by dissolving in a solvent either a copolymer of ethylene and a C3-C18 alpha-olefin or a terpolymer of ethylene, a C3-C18 alpha-olefin and a C5-C12 non-conjugated diolefin, having a molecular weight in the range of 20,000 to 1,000,000, and reacting the copolymer or terpolymer with oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature of from 60 to 250 DEG C and under a pressure of 0 to 1000 psig. The hydroperoxidised product is of lower molecular weight than the starting material.

Description

SPECIFICATION Lubricating oil containing hydroperoxidized ethylene copolymers and terpolymers as dispersants and V.l.

improvers The present invention relates to lubricating oil compositions which contain oil soluble hydroperoxidized polymeric additives which improve the sludge and varnish dispersancy as well as improving the viscosity index characteristics of the lubricating oil.

An important property of a lubricant composition is the rate at which its viscosity changes as a function of temperature. The relationship between the viscosity and temperature is commonly expressed in terms of the viscosity index (V.l.). Lubricant compositions which change little in viscosity with variations in temperature have greater viscosity index than do compositions whose viscosity is materially affected by changes in temperature. It is readily apparent, therefore, that one of the major requirements of lubricating oils or other hydrocarbon oil products is their satisfactory viscosity - temperature characteristics.These characteristics are necessary in order that the oil's viscosity will not become too lowbutwill show an equally good performance within relatively wide temperature range to which it may be exposed in service. The wider the possible temperature variations,thesmallershould be the change in viscosity with temperature. Hence, the viscosity - temperature characteristics of a lubricantwhich is used in applica tionswherewidevariations in temperature are encountered are of great importance and lubricant compositions having high viscosity indices are highly desirable.

Also, lubricants for modern, high compression, piston-type internal combustion engines must neces sarily have high detergency properties, i.e., they must have efficient sludge and varnish dispersant action and chemical and thermal stability in order to free the engines from deposits of varnish, sludge and coke-like materials. Generally, a heavy duty detergent type lubricating oil is employed in such engines in order to maintain the desired high degree of engine cleanliness and thereby promote longer engine life.

Avariety of polymeric or high molecularweight materials have been described as viscosity index improvers for lubricants. For example: U.S. Patents Nos. 3,551,336 and 3,691 teach the preparation of ethylene copolymers which act as viscosity index improversfor lubricants.

U.S. Patent No. 3,417,020 teaches a process for preparing viscosity index improvers by reacting an olefinic polymer with ozone and reduction of the resulting ozonolysis product until carbonyl groups are formed thereon.

U.S. Patent No. 3,417,020 teaches lubricating oil compositions of improved viscosities containing degraded ethylene - alpha - olefin polymers wherein the degraded polymers have been hydroxylated. The hydroxylated degraded polymers are prepared by hyd roperoxidizing the polymer with subsequent re duction ofthe hydroperoxide groups to yield de graded products containing hydroxyl groups and minor amounts of carboxyl, keto and aldehyde groups.

U.S. Patent No. 3,756,954 teaches the preparation of viscosity index improvers prepared by air oxidation of interpolymers of ethylene and propylene in the presence of an aliphatic amine.

British Application No. 2,040,296Ateaches the preparation of a viscosity index improver additive by oxidatively and mechanically degrading an ethylene copolymer containing as one of its components from 0.05to3% of 2,5-norbonradiene.

Also, a variety of compositions comprising polymeric or high molecularweight materials which incorporate nitrogen have been described as disper sants and as viscosity index improvers for lubricants.

For example: U.S. Patent No.3,316,177 teaches reaction of polyamine with the reaction product of maleic anhyd ride with an oxidized interpolymer of ethylene and propylene, as a sludge dispersant in lubricant and fuel compositions.

U.S. Patent No.3,404,091 describes the preparation of nitrogen containing polymers, useful as sludge dispersants and viscosity index improvers, by grafting polar monomers such as acrylonitrile onto hyd roperoxidized ethylene - propylene copolymers.

U.S. Patent No.3,404,092 describes the preparation of polymeric viscosity index improvers containing urethane groups by the reaction of hydroxylated ethylene - propylene copolymers with isocyanates.

U.S. Patent No.3,687,849 describes the preparation of viscosity index improvers, pour point depressants and dispersants, forfuels and lubricants, by grafting various unsaturated monomers onto a degraded, oxidized, interpolymer of ethylene and propylene.

U.S. Patent No.3,687,905 describes the preparation of additives for fuels and lubricants bythe reaction of an unsaturated acid, such as maleic acid or anhydride, with an oxidized, degraded interpolymer of ethylene and propylene, followed by reaction with a polyamine.

British Patent No.983,040 describes the preparation of detergent additives for lubricants by the reaction of a polyamine with a long chain monocarboxylicacid prepared by oxidation of an olefin polymer.

British Patent 1,027,410 describes the preparation of ashless detergents for lubricating oils bythe reaction of a polyhydroxyamine with a polymeric monocar boxylic acid.

British Patent No. 1,172,818 describes the prepara tion ofadditivesfor lube oils by the condensation of an amine with an ozonized polymer.

U.S. Patent No.3,769,216 discloses the preparation of lube oil additives by the condensation of an amine with an oxidized ethylene - propylene copolymer, prepared by air blowing in the presence of a peroxide (also see U.S. Patent 3,785,980), or by mastication of the polymer in the presence of oxygen.

We have nowfound, however, that dispersant viscosity index improversfor lubricating oils may be prepared from hydroperoxidized ethylene copolym ersandterpolymerswhich additives contain an excess of carboxylic acid groups over hydroxyl groups, and, further, that functionalization with amines is not required.

The present invention advantageously provides an effective oil composition with an ash-free detergent type inhibitor and dispersant and further, the hydroperoxidized polymeric additives used in the lubricating oil composition of this invention are very effective in markedly improving the viscosity index of the lubricatingoilcompositionstowhichtheyare added while concomitantly having excellentthickening power and shearstability.

More specifically, the present invention is con cernedwith a lubricating oil composition comprising an oil of lubricating viscosity and an effective amount of a dispersancy and viscosity index improving hydroperoxidized copolymer of ethylene with one or more alpha-olefins orterpolymer of ethylene, one or more alpha-olefins and one or more non-conjugated diolefins wherein said copolymer and terpolymer has an excess of carboxylic acid to hydroxy groups.The polymeric additive is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C18 alphaolefin or a terpolymer of ethylene, a C3-C18 alphaolefin and a Cs-C12 non-conjugated diolefin, having a molecularweight in the range of 20,000 to 1,000,000, reacting the copolymer or terpolymer with oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature of from about 60 to 2500C under a pressure of from 0 to 1000 psig.

Another embodiment of this invention is a method of lubricating the crankcase of an internal combustion engine by contacting the surface of the engine with the oil composition containing the hydroperoxidized polymer additive.

Theterm "copolymer of ethylene with one or more alpha-olefins" as used herein and in the appended claims, refers to essentially amorphous copolymers derived from essentially ethylene and alpha-olefins containing from 3 to 18 carbon atoms. The alphaolefins have the structure R-CH=CH2, where R is C1 to C16, preferably, C1 to C8 alkyl radical and preferably C1 alkyl.

Representative examples of the alpha-olefins include: propylene; 1 -butene;4-methyl-1 -pentene; 1 -pentene; 1 -hexene; 1 -heptene; 1 -octene; 1 nonene; 1 - decene; 5 - methyl - 1 - nonene; 5,5 dimethyl - 1 - octene; 4 - methyl - 1 - hexene; 4,4 dimethyl - 1 - pentene; 5 - methyl - 1 - hexene; 4 methyl - 1 heptene; 5 - methyl - 1 - heptene; 1 heptadecene, etc. Propylene is the most preferred alpha-olefin.

These copolymers can be prepared using Zieglertype catalysts. These reactions are well known and are conventionally employed. Accordingly, the present invention is not predicated upon the particular catalyst system employed in preparing the copolymer starting materials.

Additionally, terpolymers may be emplyed for producing the dispersant-viscosity index improvers herein contemplated. Theterpolymers contain ethylene, the same alpha-olefins described above, but in addition small mole percentages, such as from 0.1 to 15%, and preferably, from 1 to 10% of a third unsaturated monomer, viz., a non-conjugated diolefin is employed. These terpolymers are also prepared by conventional processes using Ziegler-type catalysts and forms no partofthe invention so far asthe production of the terpolymers is concerned.Examples of such third monomers are C5to C12 acyclic or alicyclic non-conjugated diolefins, such as 1,4 hexadiene, 1,4-pentadiene,2-methyl - 1,5- hexadiene, 1,7-octadiene,5-methylene-2- norbornene, 1,4 - cyclohexadiene, etc.

Methods of preparation ofthe copolymers and terpolymers are well known; such methods as described in many U.S. patents, such as, among others, U.S. Patent Nos. 2,700,633; 2,726,231; 2,792,288; 2,933,480; 3,000,866; 3,063,973; 3,083,621; 2,799,668; 2,975,159 and others.

The ethylene monomer unit concentration in the polymers ofthe present invention ranges in general from about 30 mol percent to about 80 mol percent, with about 20 mol percent to about 70 mol percent of the higher alpha-olefin, and Oto about 15 mol percent of the diolefin. Preferably, the ethylene-higher alphaolefin copolymers and terpolymers have viscosity average molecularweights ranging from about20,000 to 1,000,000, preferably,about40,000to500,000.

In accordance with the present invention, the heretofore mentioned copolymers and terpolymers are employed as starting materials in a controlled hydroperoxidation reaction using molecular oxygen in the presence of a free radical initiator or mixture of free radical initiators. More specifically, the hydroperoxidized ethylene copolymers and terpolymers which are used in the compositions ofthis invention are prepared by dissolving the polymer in an inert solventatatemperature intherangeoffrom about 600C to 2500C using agitation. A free radical initiator is added and oxygen, preferably in the form of air, is added to the reaction medium under a pressure of from 0 to 1,000 psig for a period of from about 0.05 to 20 hours.The introduction of oxygen into the reaction medium may also be initiated priorto the addition of the free radical initiator. The products of the reaction obtained have an excess of carboxylic acid as compared to hydroxy groups. This can occur bythefurther reaction of initially formed hydroperoxide groups or their decomposition products with the oxidizing agent.

The final polymeric product may be recovered from solution by evaporation of the solvent or by precipitation with a non-solvent or by any other suitable method. Alternatively, priorto removal ofthe inert solvent, a lubricating oil may be added directly to the reaction mixture and the inert solvent removed by vacuum distillation.

The additives can be made in batch or continuous operation. In batch operation, the individual components are added to a suitable reaction vessel together or in discrete portions and dissolved in an inert solvent. In continuous operation the reactant or reactants are added continuously to a horizontal or vertical reaction zone at appropriate feed rates in diluent or neat attemperaturesto promote easy handling, reaction and solubility.

The hydroperoxidation is carried out in solvents relatively inertto the reaction conditions. Solvents such as toluene, xylene, or mineral neutral oils can be used. Preferred solvents are benzene, chlorobenzenet - butylbenzene and the like.

The free radical initiators which may be peroxides, hydroperoxides and azo compounds, which may be used alone or as mixtures thereof, include, for example, cumene hydroperoxide, dicumyl peroxide, benzoyl peroxide, azo-bis(isobutyronitrile), tertiary butyl hydroperoxide, and the like. Preferablythefree radical initiator is cumene hydroperoxide, dicumyl peroxide, and mixtures thereof. These free radical initiators have been conventionally employed in effecting hydroperoxidation of polymers and copolymers.

It has been found that the more vigorous the oxidation conditions and the longer the length oftime maintaining such conditions, the greater the number of carboxyl groups introduced into the starting material. It is sufficient, however, that on an average at least one carboxyl is introduced into each molecule of the starting material.

The product produced by the hydroperoxidation reaction is an oil-soluble product of lower molecular weight than the starting material. The molecular weight depends upon the extent and conditions employed during the oxidation reaction. Ultimately, the intermediate hydroperoxidized polymers are converted by further oxidation reactions to fragmented or degraded polymer materials containing an excess of carboxylic acid groups over hydroxyls and wherein the carboxylated polymer materials have viscosity average molecularweight of from aboutone-halfto about one-tenth ofthe molecularweightofthe original material.The acid group content of the carboxylated polymers is in the range of from 1 to 50 mmole/1009 polymer,and preferablyfrom 1 to 10 mmoleil00g,and most preferably from 2 to 6 mmole/ 1009 polymer.

When the carboxylic acid content and hydroxy content are given in terms of mmoles per 1009 of polymer, then the ratio of carboxy to hydroxy is greaterthan 1, preferablygreaterthan Sand most preferablygreaterthan 10. The procedureforthe determination of the acid group content and hydroxy group content and definition ofthe terms used therein is given in Example 1.

The copolymers orterpolymers of this invention are employed as additives in concentrations of from about 0.05 to 2 percent, preferably from between about 0.5 to 2 percent based on the lubricating oil composition being treated. Higher concentations of upto 10% by weight and more may be used, however, the major beneficial effects are found in the ranges described.

The compositions ofthis invention have a thickening power in the range of 7-40 cSt or more. "Thickening power" as used herein is defined as the viscosity at 1 000C of a neutral oil having a viscosity at 400C of 28.6 cSt and at 1 000C of 4.7 cSt, containing 2.8 weight percent ofthe dry polymeric composition. Thickening power is thus measured as an actual viscosity of the oil to incorporation of the polymer. Thickening power is directly related to the molecularweight of the polymer, but is used instead of molecular weight because the ease of measurement and greater practical significance of data.While the thickening power of the compositions of this invention may be broadly defined as being in the range of 7-40 cSt, thickening power is more usually in the range of 15-35 cSt and, preferably, in the range of 15-25 cSt.

The carboxylated copolymers and terpolymers used in the compositions of this invention have an infrared spectrum having distinguishing absorbance peaks at frequencies of 1,370-1,380 cmu-1, 1,460-1, 470 cm 1,700-1,750cm#1 and 2,800-3,000 cm 1.

Other peaks have been observed at715-725cm#1 and 1,150-1, 160 cm-l.

More specifically, the copolymers and terpolymers used in the compositions and method ofthis invention are the intermediate reactants described in U.S.

Patents 3,785,980 and 4,132,661, which intermediate polymers in each ofthese patents are subsequently reacted with an amine to form amidated polymers useful as viscosity index improvers and dispersants.

The base lubricating oil used in the compositions of the invention are oils of lubricating viscosity, and particularlyofthetype useful in internal combustion engines and can be predominantly paraffinic, 1 naphthenic or it can be a mixture of both types of mineral oils, as well as synthetic oils which include polymers of various olefins, generally of from 10 carbon atoms or higher, alkylated aromatic hydrocarbons, etc. In general, the base oil will be a relatively highly refined mineral oil of predominantly a paraffinic nature and will have a viscosity in the range of from 2 to about 20 cSt at 1 OO"C.

The lubricating oil compositions ofthis invention are particularly useful in lubricating an internal combustion engine and may be used in both compression and spark ignition engines. Thus, they may be used to lubricate both automobile and railroad engines.

Preferred additives which may be present in the lubricating oil compositions of this invention in order to obtain a proper balance of properties and which are particularly useful in lubricating an internal combustion engine include an alkali or alkaline earth metal sulfonateorphenateorcombinationsthereof, an alkenyl succinimide or succinate or mixtures thereof and a Group II metal salt of a dihydrocarbyl dithiophosphoric acid. In railroad oil formulations the metal salt dihydrocarbyl dithiophosphate is generally omitted because of the adverse effect of these salts on silver bearings which are present in railroad engines. For railroad oil applications it is advantageousto include as an anti-wear agent from 0.01 % to 1 % and preferably 0.02% to 0.2% by weight of a sulfurized fatty acid ester.

The alkali or alkaline earth metal hydrocarbyl sulfonates may be either petroleum sulfonate, synth etically alkylated aromatic sulfonates, or aliphatic sulfonates such as those derived from polyisobutylene. One ofthe more important functions ofthe sulfonatesisto actasadetergentand dispersant.

These sulfonates are well known in the art. The hydrocarbyl group must have a sufficient number of carbon atoms to render the sulfonate molecule oil soluble. Preferably, the hydrocarbyl portion has at least 20 carbon atoms and may be aromatic or aliphatic, but is usually alkylaromatic. Most preferred for use are calcium, magnesium or barium sulfonates which are aromatic in character.

Certain sulfonates are typically prepared by sultonating a petroleum fraction having aromatic groups, usually mono- or dialkylbenzene groups, and then forming the metal salt of the sulfonic acid material.

Otherfeed-stocks used for preparing these sulfonates include synthetically alkylated benzenes and aliphatic hydrocarbons prepared by polymerizing a mono- or diolefin, for example, a polyisobutenyl group prepared by polymerizing isobutene. The metallic salts are formed directly or by metathesis using well-known procedures.

The sulfonates may be neutral or overbased having base numbers upto about400 or more. Carbon dioxide is the most commonly used material to produce the basic or overbased sulfonates. Mixtures of neutral and overbased sulfonates may be used.

The sulfonates are ordinarily used so as to provide from 0.3% to 10% by weight of the total composition.

Preferably, the neutral sulfonates are present from 0.4% to 5% by weight ofthetotal composition and the overbased sulfonates are present from 0.3% to 3% byweightofthetotal composition.

The phenates for use in this invention are those conventional products which are the alkali or alkaline earth metal salts of alkylated phenols. One of the functions ofthe phenates isto act as a detergent and dispersant. Among otherthings, it prevents the deposit of contaminants formed during high temperature operation of the engine. The phenols may be mono- or polyalkylated.

The alkyl portion of the alkylphenate is present to lend oil solubilityto the phenate. The alkyl portion can be obtained from naturally occurring or synthetic sources. Naturally occurring sources include pet roleum hydrocarbons such as white oil and wax.

Being derived from petroleum, the hydrocarbon moiety is a mixture of different hydrocarbyl groups, the specific composition of which depends upon the particular oil stock which was used as a starting material. Suitablesyntheticsourcesincludevarious commercially available alkenes and alkane derivativeswhich,when reacted with the phenol, yield an alkylphenol. Suitable radicals obtained include butyl, hexyl, octyl, decyl, dodecyl, hexadecyl, eicosyl, tricontyl, and the like. Other suitable synthetic sources ofthe alkyl radical include olefin polymers such as polypropylene, polybutylene, polyisobytylene and the like.

The alkyl group can be straight-chained or branch chained, saturated or unsaturated (if unsaturated, preferably containing not more than 2 and generally not more than 1 site of olefinic unsaturation). The alkyl radicals will generally contain from 4to 30 carbon atoms. Generally when the phenol is monoal kyl - substituted, the alkyl radical should contain at least 8 carbon atoms. The phenate may be sulfurized if desired. It may be either neutral or overbased and if overbased will have a base number of up to 200 to 300 or more. Mixtures of neutral and overbased phenates may be used.

The phenates are ordinarily present in the oil to provide from 0.2% to 27% by weight of the total composition. Preferably, the neutral phenates are present from 0.2% to 9% byweight of the total composition and the overbased phenates are present from 0.2 to 13% byweight of the total composition.

Most preferably, the overbased phenates are present from 0.2% to 5% by weig ht of the total composition.

Preferred metals are calcium, magnesium, strontium or barium.

The sulfurized alkaline earth metal alkylphenates are preferred. These salts are obtained by a variety of processes such as treating the neutralization product of an alkaline earth metal base and an alkylphenol with sulfur. Conveniently the sulfur, in elemental form, is added to the neutralization product and reacted at elevated temperatures to produce the sulfurized alkaline earth metal alkylphenate.

If more alkaline earth metal base were added during the neutralization reaction than was necessary to neutralize the phenol, a basicsulfurized alkaline earth metal alkylphenate is obtained. See, for exam- ple, the process of Walker et al, U.S. Patent No.

2,680,096. Additional basicity can be obtained by adding carbon dioxide to the basic sulfurized alkaline earth metal alkylphenate. The excess alkaline earth metal base can be added subsequent to the sulfurization step but is conveniently added at the same time as the alkaline earth metal base is added to neutralize the phenol.

Carbon dioxide is the most commonly used material to produce the basic or "overbased" phenates. A process wherein basic sulfu rized alkaline earth metal alkylphenates are produced by adding carbon diox ideisshownin Hanneman, U.S. Patent No.3,178,368.

The Group II metal salts of dihydrocarbyl dithiophosphoric acids exhibit wear, antioxidant and thermal stability properties. Group II metal salts of phosphorodithioic acids have been described previously. See, for example, U.S. Patent No.3,390,080, columns 6 and 7, wherein these compounds and their preparation are described generally. Suitably,the Group II metal salts of the dihydrocarbyl dithiophosphoric acids useful in the lubricating oil composition ofthisinvention contain from about4toabout 12 carbon atoms in each of the hydrocarbyl radicals and may be the same of different and may be aromatic, alkyl or cycloalkyl. Preferred hydrocarbyl groups are alkyl groups containing from 4to 8 carbon atoms and are represented by butyl, isobutyl, sec.-butyl, hexyl, isohexyl, octyl, 2-ethylhexyl and the like. The metals suitableforforming these salts include barium, calcium, strontium, zinc and cadmium, of which zinc is preferred.

Preferably, the Group! metal salt of a dihydrocarbyl dithiophosphoric acid has the following formula:

wherein: R2 and 133 each independently represent hydrocar- byl radicals as described above, and M1 represents a Group II metal cation as described above.

The dithiophosphoric acid salt is present in the lubricating oil compositionsofthis invention in an amount effective to inhibit wear and oxidation of the lubricating oil. The amount ranges from about 0.01 to about4 percent by weight of the total composition, preferably the salt is present in an amount ranging from about 0.1 to about 2.5 percent by weight of the total lubricating oil composition. For example, for railroad oil applications it is preferablethatthe lubricating oil contain none or very little metal dihydrocarbyl dithiophopohoric acid salt since these compounds have an adverse effect on silver bearings which are present in railroad engines.

The alkenyl succinimide or succinate or mixtures thereof are present to, among otherthings, act as a dispersant and prevent formation of deposits formed during operation of the engine. The alkenyl succinimides and succinates are well known in the art. The alkenyl succinimides are the reaction product of a polyolefin polymer- substituted succinic anhydride with an amine, preferably a polyalkylene polyamine, and the alkenyl succinates are the reaction product of a polyolefin polymer - substituted succinic anhydride with monohydricand polyhydric alcohols, phenols and naphthols, preferably a polyhydric alcohol containing at leastthree hydroxy radicals. The polyolefin polymer-substituted succinic anhydrides are obtained by reaction of a polyolefin polymer or a derivative thereof with maleic anhydride.The succinic anhydride thus obtained is reacted with the amine or hydroxy compound. The preparation ofthe alkenyl succinimides has been described many times in the art. See, for example, U.S. Patent Nos. 3,390,082, 3,219,666and3,172,892.The preparation ofthe alkenyl succinates has also been described in the art.

See, for example, U.S. Patent Nos. 3,381,022 and 3,522,179.

Particularly good results are obtained with the lubricating oil compositionsofthis invention when the alkenyl succinimide or succinate is a polyisobutene - substituted succinic anhydride of a polyalkylene polyamine or polyhydric alcohol, respectively.

The polyisobutene from which the polyisobutene substituted succinic anhydride is obtained by polymerizing isobutene and can vary widely in its compositions. The average number of carbon atoms can range from 30 or less to 250 or more, with a resulting number average molecularweight of about 400 or less to 3,000 or more. Preferably, the average number of carbon atoms per polyisobutene molecule will range from about 50 to about 100 with the polyisobutenes having a number average molecular weight of about 600 to about 1,500. More preferably, the average number of carbon atoms per polyisobutene molecule ranges from about 60to about 90, and the number average molecularweight ranges from a bout 800 to 1,300.The polyisobutene is reacted with maleic anhydride according to well-known procedures to yield the polyisobutene - substituted succinic anhydride.

In preparing the alkenyl succinimde, the substituted succinic an hydride is reacted with a polya Ikylene polyaminetoyieldthecorresponding succinimide. Each alkylene radical ofthe polyalkylene polyamine usually has up to about8 carbon atoms.

The number of alkylene radicals can range up to about 8. The alkylene radical is exemplified by ethylene, propylene, butylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, octamethylene, etc. The number of amino groups generally, but not necessarily, is one greaterthan the number of alkylene radicals present in the amine, i.e., if a polyalkylene polyamine contains 3 alkylene radicals, it will usually contain 4 amino radicals. The number of amino radicals can range up to about 9.

Preferably, the alkylene radical contains from about 2 to about4carbon atoms and all amine groups are primary or secondary. In this case, the number of amine groups exceeds the number of alkylene groups by 1. Preferably the polyalkylene polyamine contains from 3to 5 amine groups. Specific examples of the polyalkylene polyamines include ethylenediamine, diethylenetriamine, triethylenetetramine, propylenediame, tripropylenetetramine, tet raethylenepentamine, trimethylenediamine, pentaethylenehexamine, di-(trimethylene)triamine, tri(hexamethylene)tetramine, etc.

Other amines suitable for preparing the alkenyl succinimide useful in this invention include the cyclic amines auch as piperizine, morpholine and dipiperizines.

Preferably the alkenyl succinimides used in the compositions of this invention have the following formula:

wherein: a. R, represents an alkenyl group, preferably a substantially saturated hydrocarbon prepared by polymerizing aliphatic monoolefins. Preferably R1 is prepared from isobutene and has an average number ) of carbon atoms and a number average molecular weight as described above; b. the "Alkylene" radical representsasubstantial- ly hydrocarbyl group containing up to about 8 carbon atoms and preferably containing from about 2 to 4 carbon atoms as described hereinabove; c. A represents a hydrocarbyl group, an amine substituted hydroca rbyl group, or hydrogen.The hydrocarbyl group and the amine - substituted hydrocarbyl groups are generally the alkyl and amino-substituted alkyl analogs of the alkylene radicals described above. Preferably A represents hydrogen; d. N represents an integer of from about 1 to 10, and preferably from about3to 5.

The alkenyl succinimide can be reacted with boric acid or a similar boron-containing compound to form borated dispersants having utility in this invention.

The borated succinimides are intended to be included within the scope of the term "alkenyl succinimide".

The alkenyl succinates are those of the above described succinic anhydride with hydroxy com pounds which may be aliphatic compounds such as monohydric and polyhydric alcohols or aromatic compounds such as phenols and naphthols. The aromatic hydroxy compounds from which the esters may be derived are illustrated by the following specific examples: phenol, beta - naphthol, alpha naphthol, cresol, resorcinol, catechol, p,p' dihyd roxybiphenyl, 2- chlorophenol, 2,4- dibutylphenol, propenetetramer-substituted phenol, didodecyl phenol,4,4'-methylene-bisphenol,alpha -decyl- beta - naphthol, polyisobutene (molecular weight of 1000) - substituted phenol, the condensation product of heptylphenol with 0.5 mole of formaldehyde, the condensation product of octylphenol with acetone, di(hydroxyphenyl)oxide, di(hydroxyphenyl) sulfide, di(hydroxyphenyl) disulfide, and 4 - cyclohexylphenol. Phenol and alkylated phenols having uptothree alkyl substituents are preferred. Each ofthe alkyl substituents may contain 100 or more carbon atoms.

The alcohols from which the esters may be derived preferably contain up to about40 aliphatic carbon atoms. They may be monohydric alcohols such as methanol, ethanol, isooctanol, dodecanol, cyclohexanol, cyclopentanol, behenyl alcohol, hexatriacontanol, neopentyl alcohol, isobutyl alcohol, benzyl alcohol, betaphenylethyl alcohol, 2 - methylcyclohex- anol, beta - chloroethanol, monomethyl ether of ethylene glycol, monobutyl ether of ethylene glycol, monopropyl ether of diethylene glycol, monododecyl ether oftriethylene glycol, monooleate of ethylene glycol, monostearate of diethylene glycol, secpentyl alcohol, tert-butyl alcohol, 5 - bromo - dodecanol, nitro - octadecanol and dioleate of glycerol.The polyhydric alcohols preferably contain from 2to about 10 hydroxy radicals.They are illustrated by, for example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethyiene glycol, di propylene glycol, tripropylene glycol, dibrutyleneglycol,tri- butylene glycol, and other alkylene glycols in which the alkylene radical contains from 2to about 8 carbon atoms. Other useful polyhydric alcohols include glycerol, monooleateofglycerol, monomethyl ether of glycerol, penetraerythritol, 9,10 - dihydroxy stearic acid, methyl ester of 10-dihydroxystearicacid, 1,2 - butanediol, 2,3 - hexanediol, 2,4 - hexanediol, pinacol, erythritol, arabitol sorbitol, mannitol, 1,2 cyclohexanediol, and xylene glycol. Carbohydrates such as sugars, starches, celluloses, etc., likewise may yield esters.The carbohydrates may be exemplifed by a glucose, fructose, sucrose, rhamnose, mannose, glyceraldehyde, and galactose.

An especially preferred class of polyhydric alcohols are those having atleastthree hydroxy radicals, some of which have been esterifiedwith a monocarboxylic acid having from about 8to about 30 carbon atoms such as octanoic acid, oleic acid, stearic acid, linoleic acid, dodecanoicacid, or tall oil acid. Examples of such partially esterified polyhydric alcohols are the monooleate of sorbitol, distearate of sorbitol, monooleate of glycerol, monostearate of glycerol, di-dodecanoate of erythritol.

The esters may also be derived from unsaturated alcohols such as allyl alcohol, cinnamyl alcohol, propargyl alcohol, 1 - cyclohexene - 3 - ol, an oleyl alcohol. Still other classes ofthe alcohols capable of yielding the esters ofthis invention comprises the ether-alcohols and amino-alcohols including, for example,the oxy-alkylene-, oxy-arylene-, amino alkylene-, and amino - arylene- substituted alcohols having one or moe oxy-alkylene, amino-alkylene or amino-arylene oxy-arylene radicals.They are exemplified by Cellosolve, carbitol, phenoxy-ethanol, heptylphenyl - (oxypropylene)6- H, octyl - (oxyethylene)30 - H, phenyl(oxyoctylene)2 - H, mono(heptyl - phenyl oxypropylene) - substituted glycerol, poly (styrene oxide), amino - ethanol, 3 - amino ethyl - pentanol, di (hydroxy - ethyl) amine, p - aminophenol, tri (hydroxypropyl) amine, N - hydroxyethyl ethylene diamine, N, N, N', N'-tetrahydroxy-trimethylene diamine, and the like. Forthe most part, the etheralcohols having upto about 150 oxy- alkylene radicals in which the alkylene radical containsfrom 1 to about 8 carbon atoms are preferred.

The esters may be di-esters of succinic acids or acidic esters, i.e., partially esterified succinic acids, as well as partiallyesterified polyhydricalcohols or phenols, i.e., esters having free alcoholic or phenolic hydroxyl radicals. Mixtures of the above-illustrated esters likewise are contemplated within the scope of the invention.

The alkenyl succinates can be rected with boric acid or a similar boron-containing compound to form borated dispersants having utility in this invention.

Such borated succinates are described in U.S. Patent No.3,533,945. The borated succinates are intended to be included withinthe scope oftheterm "alkenyl succinate." The alkenyl succinimide and succinates are present in the lubricating oil compositions ofthe invention in an amount effective to act as a dispersant and prevent the deposit ofcontaminatantsformed in the oil during operation ofthe engine. The amount of alkenyl succinimide and succinates can range from about 1 percent to about 20 percent weight of the total lubricating oil composition. Preferablythe amount of alkenyl succinimide of succinate present in the lubricating oil composition ofthe invention ranges from about 1 to about 10 percent by weight of the total composition.

The sulfurized fatty acid esters which act as anti-wear agents are presentfrom 0% to 1 % and for railroad oil applications are present in the range of from 0.01% to 1 % by weight. The esters are prepared by reacting sulfur, sulfur monochloride, andlor sulfur dichloridewith an unsaturated fatty ester under elevated temperatures. Typical esters include C1-C20 alkyl esters of C8-C24 unsaturated fatty acids, such as palmitoleic, oleic, ricinoleic, petroselinic, vaccenic, linoleic, linolenic, oleostearic, licanic, paranaric,tariric, gadoleic, arachidonic, cetoleic, etc. Particularly good results have been obtained with mixed unsaturated fatty acid esters, such as are obtained from animal fats and vegetable oils, such as tall oil, linseed oil, olive oil, caster oil, peanut oil, rape oil, fish oil, sperm oil, and so forth.

Examplaryfatty esters include lauryl tallate, methyl oleate, ethyl oleate, laurel oleate, cetyl oleate, cetyl linoleate, lauryl ricinoleate, oleyl linoleate, oleyl stearate, and alkyl glycerides.

Cross-sulfurized ester olefins, such as a sulfurized mixture of C10-C25 olefins with fatty acid esters of C10-C2sfatty acids and C1-C25 alkyl oralkenyl alcohols, whereinthefattyacid andlorthealcoholisunsatu- rated may also be used.

Sulfurized olefins are prepared by the reaction of the C3-C6 olefin or a low - molecular - weight polyolefin derived therefrom with asulfur-contain- ing compound such as sulfur, sulfur monochloride, 5 and/orsulfurdichloride.

Other additives, such as the detergents, rust and corrosion inhibitors, pour point depressants, metal deactivators, a nti-oxida nts, anti-wear agents, foam inhibitors, etc., may also be present in thefinished ) lubricant. These other additives will be present in conventional concentrations.

Theinvention is further illustrated bythefollowing examples, which are given without any intention that the invention be limited thereto.

Example 1 A solution containing 8% by weight of an ethylene/ propylene11,4- hexadieneterpolymer(a product manufactured by Du Pont Company, Wilmington, Delaware and sold under the trade name Ortholeum 2038, which is a terpolymer having about 60 mole percent ethylene groups, 39 mole percent propylene groups and 1 mole percent 1,4- hexadiene groups and having a molecularweight of about 250,000) in chlorobenzene was prepared and heated to 1 000C. To this solution was continuously added at an appropri ate rate in order to supply 4.2% by weight based on the weight of polymer of dicymyl peroxide and 1.8% by weight based on the weight of polymer of cumene hydroperoxide.The reaction mixture was continuously passed through a three-qua rter inch stainless steel tubular reactor such that the residence time in the reactorwas2.75 minutesata reaction temperature of 1 900C and a pressure of 200 psig. Air was continuously passed into the reactor tube at 0.35 cm2/gm polymer at 200 psig. Sufficient 100 Neutral Oil was added to yield a 15% by weight of product in solution when the chlorobenzene solventwas removed. The chlorobenzene solvent was removed by distillation at reduced pressure. The viscosity or thickening power of the polymer product (viscosity at 100"C, 2.8% polymer in RPM 130N)was 17.8 cSt.The acid content was 4.8 mmole COOH/100g polymer and the hydroxyl content was 0.28 mmole OH/1 00g polymer as calculated below.

The acid and hydroxyl content was determined as follows: A Determination of Acid Group Content 40.0g of a solution of oxidized polymer intermedi ate in 100 neutral mineral oil (containing about 5-6 g of polymer) was dissolved in 100 ml of xylenes. 10.0 ml of 0.0999M NaOH solution was added, and the mixture was refluxedfor30 minutes. 75 ml of isopropyl alcohol was added followed by 1 ml of phenolphthalein indicator (0.1% in ethyl alcohol). The mixture was titrated to the phenolphthalein end point with 0.100N HCI. The acid functionality per 1009 of polymer is calculated using the formula below.

mmole RCO2H = (ml NaOH x M NaOH)-(ml HCI x M HCI) X 100 1009 Polymer Wt of Polymer mmole RCO2H = (10.0 x 0.0999)-(7.1 x 0.100) X 100 5.85 = 4.9 mmole RCO2H/100g polymer A Determination of Hydroxyl Number Description of Method The dibutyl tin dilaurate - catalyzed reaction between alcohols and isocyanates was used to measure the hydroxyl content of the oxidized polymer. Using the reaction conditions described below, acid groups are not reactive, only hydroxyl functional groups are consumed. The difference in the concentration of isocyanate before and after reaction (as measured by infrared spectorscopy) indicates the amount of hydroxyl groups in the polymer.

Procedure Asolution of 1.009 phenylisocyanate in 50 ml dry toluene was prepared. Several dilutions of the stock isocyanate solution were made and an infrared absorbance versus concentration curve was obtained using the IR absorbance at 2265 cm- divided by the IR cell path length (in cm). The slope ofthis line gave a concentration factor of 0.118 mmole isocyanate/ absorbance unit cm-1.

1009 of a solution of oxidized polymer intermediate in chlorobenzene (containing about 12-159 polymer) was treated with 2.0 ml ofthe isocyanate stock solution and 2 drops of dibutyl tin dilaurate catalyst.

The mixture was stirred and heated at80 Cfor100 min. A blank consisting of 1 00g of chlorobenzene was run under the same conditions. An infrared spectrum of each solution was recorded in a 0.0171 cm path length NaCI cell. The hydroxyl group contentwas calculated from the isocyanate consumption bythe polymer solution, correcting for subtracting the blank, using the formula below.

mmole OH/100g polymer = 2265 blank - 2265 poly X (ICF) PL X100 WP where 2265 poly = IR absorbance for polymer solution 2265 blank = IR absorbance for blank solution ICF = isocyanate concentration factor mmole isocyanate (0.118 ABS . cm-l PL = IR cell path length (cm) WP = Weight of polymer mmoleOH/100g polymer (0.027 - 0.021) ABS (0.118 mmole) (100) 0.0171 cm ABS cm-l 15.0 = 0.28 mmole Or/1009 polymer Thus the product of Example 1 had a COOH:OH ratio of 4.9:0.28 or about 19:1.

Example 2 Asolution containing 8% by weight ofthe ethylene / propylene/ 1,4 - hexadiene terpolymer of Example 1 in chlorobenzenewas prepared and heated to 100 C.

To this solution was continuously added at an approriate rate in order to supply 0.2% by weight based on the weight of polymer of dicumyl peroxide.

The reaction mixture was continuously passed through a three-quarter inch stainless steel tubular reactor such that the residence time in the reactor was 2.75 minutes at a reaction temperature of 1 900C and a pressure of 200 psig. Airwas continuously passed into the reactor tube at 1.7 cm2/gm polymer at 200 psig. Sufficient 100 neutral oil was added to yield a 15.7% byweight of product in solution when the chlorobenzenesolventwas removed. The chlorobenzene solvent was removed by distillation at reduced pressure.The viscosity or thickening power of the polymer product (viscosity at 1 000C, 2.8% polymer in RPM 130N) was 17.8 cSt,the acid content was 4.3 mmole COOH/100g polymer and the hydroxyl content was 0.06 mmole OH/100g polymer giving a ratio of 4.3 to 0.06 or about 72:1 acid to hydroxyl.

Multi-grade lubricating oils with good dispersancy characteristics may be prepared using the product of this example.

Example 3 Thirty parts ofthe commercial ethylene/ propylene /1,4 - hexadiene terpolymer of Example 1 was dissolved in 365 parts of xylene at 200"F over a period of about 16 hours with stirring. The temperature was raised to 250"F and .118 parts dicumyl peroxide was added to the polymer solution. An air sparge of 1 ft3/min was used to introduce oxygen into the polymer solution over a period of about 6 hours.

Sufficent 100 Neutral Oil was added to yield a 12% by weight of product in solution when the xylene solvent was removed. The xylene solvent was removed by distillation at reduced pressure. The viscosity or thickening power of the polymer product (viscosity at 100 C,2.8% dry polymer in RPM 130N)was 16cSt.

Example 4 Thirty pounds of an ethylene/propylene copolymer rubber (a product manufactured by B. F. Goodrich and sold underthe trade name EPCAR 405 which is an ethylene / propylene copolymer having about 60 mole percent ethylene and 40 mole percent propylene and having a Mooney viscosity of 60) was dissolved in 345 pounds of chlorobenzene at 210"F over a period of aboutfive hours. The temperature was raised to 250 F and 270 ml of a 10% by weight dicumyl peroxide was added to the polymer solution.

An airspargeof 0.5 ft3/m in was used to introduce oxygen into the solution over a period of about 5 hours. An additional 25 ml of 10 percent by weight dicumyl peroxide was added every 30 minutes over the 5 - hour reaction period. After a nitrogen sparge for 30 minutes, sufficient 100 neutral oil was added to yield a 12% byweight of product in solution when the chlorobenzenewas removed. The chlorobenzene solvent was removed by distillation at reduced pressure. The viscosity orthickening power of the polymer product (viscosity at 1 00'C, 2.8% dry polym er in RPM 130N) was 17 cSt. The acid contentwas 5.8 mmoles COOH/100g polymer and the hydroxyl content was 0.23 mmoles OH/100g polymer giving a ratio of 5.8:0.23 or about 25:1 acid to hydroxyl.

Multi-grade lubricating oil with good dispersancy characteristics may be prepared using the product of this Example.

Example 5 The lubricating oil compositions ofthis invention were evaluated in the standard Sequence V-D automotive enginetestand the 1-G2 caterpillar engine test. In the Sequence V-D and 1-G2 engine tests, lubricants containing the experimental additives are charged respectively to a standard internal combustion engine and to a diesel engine. The engines are operated atan assigned load and temperature, and at the end of a prescribed time and engines are disassembled and examined for deposits and wear.

These enginetests are standard methodswell known in the industry.

Also, viscosity measurements at 1 00'c, 400C and 0 C show acceptable viscosity measurements and with the use of pour point depressants, acceptable viscosity measurements at -32"C are obtained.

A. Standard Se quence V-D Engine Test Formulated 10W-40 oils containing the additives shown in Table I were prepared and tested in a Sequence V-D Test method phase 9-2 (according to candidate testforASTM) as shown in Table II. This procedure utilizes a Ford 2.3-literfour-cylinder engine. The test method simulates a type of severe field test service characterized by a combination of low speed, low temperature "stop and go" city driving and moderate turnpike operation. The effectiveness of the additives in the oil is measured in terms ofthe protection provided against deposits and valve train wear.

TABLE I Test Oil Formulations (mmoles/kg except where noted) A1 B2 C2 D5 E5 F2,3 G2t4 Product of Example 1 1.73% - 1.73% - - - Product of Example 3 - 1.65% - - - - Amine functionalized olefin terpolymer - - - - - 1.70% Olefin copolymer - - - - - - 0.55% Calcium phenate 20 20 20 20 20 20 20 Zinc dialkyl phosphate 22.5 22.5 22.5 22.5 22.5 22.5 22.5 Overbased calcium sulfonate 30 - 30 30 30 30 30 Polyisobutenyl succinimide - 1.5% 6% - 6% - (50% concentrate in oil) Overbased magnesium sulfonate - 30 - - - - 1 Exxon 150N Oil formulated to 10W-40 2 Sun 148N Oil formulated to 10W-40 3 V.I. improver prepared by the condensation of an alkylene polyamine with a hydroperoxidized ethylene-propylene-1,4 hexadiene terpolymer as described in U.S. Patent No. 3,785,980.

Paratone 716, a non#ispersant, non-hydroperoxidized olefin copolymer V.I. improver commercially available from Exxon Chemicals.

Oil.

The data in Table 11 demonstrate that formulations A, B and C containing the hydroperoxidized polymers of this invention have dispersant properties better than an ethylene copolmer V.I. im prover and com pa- rabble to an aminefunctionalized hydroperoxidized ethyleneterpolymerofthe prior art.

TABLE III Caterpillar 1-G2 Test Top Grove Formulation Time-Hrs. Groves Lands Fill % WTD H 60 59-94-8-0 40-9-7 58 216 120 73-115-3-5 57-7-9 73 268 I 120 90-171-3-6 76-14-29 89 388 B. Caterpillar 1-G2 Test The compositions of this invention were tested in a Caterpillar 1 -G2 test in which asingle-cylinderdiesel engine having a 5-1/8" bore by 6-1/2" stroke is operated underthefollowing conditions: timing, degrees BTDC, 8; brake means effective pressure, psi 141; brake horsepower 42;Btu's per minute 5850; speed 1800 RPM; air boost, 53" Hg absolute, air temperature in, 255"F; watertemperatu re out, 1 90"F; and sulfur infuel,0.4%w. Atthe end of each 12 hours of operation, sufficient oil is drained from the crankcase to allow addition of 1 quart of new oil. In the test on the lubricating oil compositions ofthis invention, the 1 -G2 test is run for 60 and 120 hours. At the end ofthe noted time period, the engine is dismantled and rated for cleanliness. The Institute of Petroleum Test Number 247/69 merit rating system for engine wear and cleanliness, accepted byASTM, API and SAE, is the rating system used to evaluate the engine.The over-all cleanliness is noted as WTD, which is the summation ofthe above numbers.Lower values represent cleaner engines.

The base oil used in this test is a Sun Tulsa 148N/250N base oil formulated with sufficient viscos ity index-dispersant about 12% by weight) to prepare a 15W-40 oil containing 3% of a 50% concentrate in oil of an isobutenyl succinimide, 10 mmoles/kg calcium sulfonate, 20 mmoles/kg overbased calcium phenate, 45 mmoles/kg overbased magnesium sulfonate; 18 mmoles zinc dialkyl dithiophosphate, 1% combination of cracked wax olefin and sulfurized calcium phenate. Formulation H in Table Ill contains the viscosity index-dispersant of Example 1, and formulation I contains the aminefunctionalized olefin terpolymer used in formulation F in Table 1.

TABLE II Sequence V-D Performance Com Lobe Wear Average Piston Average x l0#3-Inch Test Oil Sludge Varnish Varnish Average Maximum A 7.2 6.6 6.6 0.5 0.9 B 9.7 6.7 5.0 0.5 0.9 C 9.7 7.2 7.0 0.5 0.8 D 6.4 6.4 6.3 2.7 8.3 E 9.6 6.8 6.8 0.4 0.5 F 5.9 6.6 7.1 0.4 0.6 G 6.5 5.6 5.1 0.6 0.7

Claims (25)

CLAIMS 1. A lubricating oil composition comprising an oil of lubricating viscosity and an effective amount of a dispersancey and viscosity index improving hyd roperoxidized copolymer of ethylene with one or more alpha-olefins orterpolymer of ethylene, one or more alpha-olefins and one or more non-conjugated diolefinswherein said copolymer and terpolymer has an excess of carboxylic acid to hydroxy groups and is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C18 alpha - olefin or a terpolymer of ethylene, a C3-C18 alpha - olefin and a C5-C12 non-conjugated diolefin, having a molecularweight in the range of 20,000 to 1,000,000, reacting the copolymerorterpolymerwith oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature of from 600 to 250 C and under a pressure of onto 1000 psig. 2. A lubricating oil composition comprising: (a) a major amount of an oil of lubricating viscosity; and (b) an effective amount of each of the following:

1. an alkenyl succinimide orsuccinate or mixturesthereof;

2. an overbased or neutral alkali or alkaline earth metal hydrocarbyl sulfonate or phenate or mixtures thereof;;

3. a dispersancey and viscosity index improving hydroperoxidized copolymer of ethylene with one or more alpha - olefins orterpolymer of ethylene, one or more alpha - olefins and one or more non-conjugated diolefins wherein said copolymer and terpolymer has an excess of carboxylic acid to hydroxy groups and is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C18 alpha - olefin ora terpolymer of ethylene, a C3-C18alpha - olefin and a C5-C12 non-conjugated diolefin, having a molecularweight in the range of 20,000 to 1,000,000, reacting the copolymerorterpolymerwith oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature of from 600 to 2500C and under a pressure of O to 1000 psig.

3. The lubricating oil composition of Claim 2 which additionally contains a Group II metal salt of a dihydrocarbyl dithiophosphoric acid.

4. The lubriating oil composition of Claim 2 which additionally contains a sulfurized fatty acid ester.

5. The lubricating oil composition of Claims 1 or 2 wherein the copolymer orterpolymer of ethylene comprisesfrom 30 to 80 mole percent ethylene,70 to 20 mole percent propylene and 0 to 15 mole percent of a C5to C12 non-conjugated diolefin.

6. The lubricating oil composition of Claim 5 wherein theterpolymer of ethylene contains from 1.0 to 10 mole percent of a C5to C12 non-conjugated diolefin.

7. The lubricating oil composition of Claim 6 wherein the non-conjugated diolefin is 1,4-hex- adiene.

8. The lubricating oil composition of Claims 1 or 2 wherein the free radical initiator catalyst is selected from the group consisting of dicumyl peroxide and cumene hydroperoxide and mixtures thereof.

9. A method of improving the sludge and varnish dispersancy properties and increasing the viscosity index of an oil of lubricating viscosity which comprises incorporating in said lubricating oil an effective amount of a dispersancy and viscosity index improving hydroperoxidized copolmer of ethylene with one or more alpha-olefins orterpolymer of ethylene, one or more alpha - olefins and one or more nonconjugated diolefins wherein said copolymer and terpolymer has an excess of carboxylic acid to hydroxy groups and is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C18 alpha olefin or a terpolmer of ethylene, a C3-C18 alpha olefin and a C5-C12 non - conjugated diolefin, having a molecular weight in the range of 20,000 to 1,000,000, reacting the copolymerorterpo [ ymerwith oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature offrom 60" to 2500C and under a pressure of0 to 1000 psig.

10. A method of improving thesludgeand varnish dispersancy properties and increasing the viscosity index of an oil lubricating viscosity which comprises incorporating in said lubricating oil an effective amount of each ofthe following:

1. an alkenyl succinimide or succinate or mixturesthereof;

2. an overbased or neutral alkali or alkaline earth metal hydrocarbyl sulfonate or phenate or mixtures thereof;;

3. a dispersancy and viscosity index improving hydroperoxidized copolymer of ethylene with one or more alpha - olefins orterpolymer of ethylene, one or more alpha - olefins and one or more non conjugated diolefinswherein said copolymerand terpolymer has an excess of carboxylic acid to hydroxy groups and is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C18 alpha olefin oraterpolymerofethylene,aC3-C18alpha- olefin and a C5-C12 non - conjugated diolefin, having a molecularweight in the range of 20,000 to 1,000,000, reactingthecopolymerorterpolymerwith oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature of from 600to 2500C and under a pressure of Oto 1000 psig.

11. The method of Claim 10 wherein a Group II metal salt of a dihydrocarbyl dithiophosphoric acid is additionally incorporated into said lubricating oil.

12. The method of Claim 10 wherein a sulfurized fatty acid ester is additionally incorporated into said lubricating oil.

13. The method of Claims 9 or 10 wherein the copolymer orterpolymer of ethylene comprises from 30 to 80 mole percent ethylene, 70 to 20 mole percent propylene and Oto 15 mole percent of a C5 to C12 non-conjugated diolefin.

14. The method of Claim 13 wherein the terpolymerofethylenecontainsfrom 0.1 to 10 mole percent of a C5to C12 non-conjugated diolfin.

15. The method of Claim 14wherein the nonconjugated diolefin is 1,4 - hexadiene.

16. The method of Claims 9 or 10 wherein the free radical initiator catalyst is selected from the group consisting of dicumyl peroxide and cumene hydroperoxide and mixtures thereof.

17. In the method of lubricating the crankcase of an internal combustion engine by contacting the surfaces of said engine with an oil of lubricating viscosity, the improvement wherein a sufficient amount of a hydroperoxidized copolymer of ethylene with one or more alpha - olefins orterpolymer or ethylene, one or more alpha - olefins and one or more non-conjugated diolefinswherein said copolymer and terpolymer has an excess of carboxylic acid to hydroxy groups and is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C,8alpha olefin or a terpolymer of ethylene, a C3-Ca8 alpha olefin and a C5-C12 non-conjugated diolefin, having a molecular weight in the range of 20,000 to 1,000,000, reacting the copolymer orterpolymer with oxygen in the presence of a free radical initiator, the reaction being carried out at a temperature of from 60" to 2500C and under a pressure of0 to 1000 psig, is added to the oil in orderto improve the dispersancy and viscosity index of the oil.

18. A method of lubricating the crankcase of an internal combustion engine which comprises contacting the surfaces of said engine with a lubricating ail composition comprising: (a) a major amount of an oil of lubricating viscosity; and (b) an effectiveamountofeachofthefollowing: T. an alkenyl succinimide or succinate of mixtures thereof;

2. an overbased or neutral alkali or alkaline earth metal hydrocarbyl sulfonate or phenate or mixtures thereof;;

3. a dispersancy and viscosity index improving hydroperoxidized copolymer of ethylene with one or more alpha - olefins orterpolymer of ethylene. one or more alpha - olefins and one or more non-conjugated diolefinswherein said copolymer and terpolymer has an excess of carboxylic acid to hydroxy groups and is prepared by dissolving in a solvent a copolymer of ethylene and a C3-C18 alpha-olefin or a terpolymer of ethylene, a C3-C18 alpha - olefin and a C5-C12 non-conjugated diolefin, having a molecularweight in the range of 20,000 to 1,000,000, reacting the copolymer orterpolymer with oxygen in the presence of a free radical initiator,the reaction being carried out at a temperature of from 60" to 2500C and under a pressureofOto 1000 psig.

19. The method of Claim 18 wherein said com- position additionally contains a Group II metal salt of a dihydrocarbyl dithiophosphoric acid.

20. The method of Claim 18 wherein said com- position additionally contains a sulfurized fatty acid ester.

21. The method of Claims 17 or 1 8wherein the copolymerorterpolymerofethylenecomprisesfrom 30 to 80 mole percent ethylene, to 20 mole percent propylene and 0 to 15 mole percent of a C5to C12 non-conjugated diolefin.

22. The method of Claim 21 wherein the terpolymer of ethylene contains from 0.1 to 10 mole percent of a C5 to C12 non-conjugated diolefin.

23. The method of Claim 22wherein the nonconjugated diolefin is 1, 4-hexadiene.

24. The method of Claims 17 or 18wherein the free radical initiator catalyst is selected from the group consisting of dicumyl peroxide and cumene hydroperoxide and mixtures thereof.

25. A lubricating oil composition in accordance with Claim 1, substantially as described in the foregoing Example 5.