US3194763A - Polymeric composition and lubricant containing it - Google Patents

Description

United States Patent 3,l4,763 POLYMERI C(BMPGSHTIUN AND LUBRICANT CQNTAINING lT Chester D. Gordon, Richmond, Frank A. Stuart, Grinds, and Alfred Goldschmidt, El Cerrito, Qalifi, assignors to California Research Corporation, San Francisco, Calif., a corporation of Delaware No Drawing. Continuation of applications Ser. No.

38,705 and Ser. No. 38,749, June 27, N60. This application Dec. 18, 1962, Ser. No. 245,409

2 Claims. (Cl. 252-515) This application is a continuation of Gordon, Stuart and Goldschmidt patent application No. 38,705, filed June 27, 1960; and Goldschmidt, Gordon and Stuart patent application No. 38,749, filed June 27, 1960, both of which applications are now abandoned.

This invention is directed to a novel polymeric composition. More particularly, the invention is concerned with a superior new polymeric composition useful as an ashless detergent for internal combustion engine lubricating oils and as a dispersant for engine fuels and hydrocarbon compositions in general. The polymeric composi tion of the present invention is also useful as a promoter in grease manufacture for improving the yields of soap thickened greases.

Lubricant compositions are primarily useful in the reduction of friction between rubbing surfaces as in the case of pistons, bearings and other moving parts of engines. In addition, the lubricant compositions prevent the deposit of solid materials on engine surfaces coming in contact with the lubricant composition. Such deposits tend to interfere with normal circulation of the lubricant composition and act as abrasives causing excessive wear of engine parts.

A substantial proportion of modern engine deposits is attributable to the additives commonly present in lubricant compositions, particularly in the case of metal-containing additives. As a lubricant composition is consumed by combustion on cylinder walls and the like in the engine, such metal-containing additives may form an ash which deposits out on the engine surfaces coming into contact with the lubricant composition.

In accordance with the present invention a superior new ashless detergent lubricant composition has been discovered comprising a major portion of an oil of lubricating viscosity and a minor portion sufiicient to enhance the detergent characteristics of the composition of an oil-soluble copolymer which comprises (A) at least one oil-solubilizing monomer having a single polymerizable ethylenic group and containing a monovalent hydrocarhon group of from 4 to 30 aliphatic carbon atoms, more particularly, an alkyl ester of an unsaturated monocarboxylic acid of 3 to carbon atoms and (B) at least one oxirane substituted monomer having a single polymerizable ethylenic group and an epoxy group, more particularly, a glycidyl ester of an unsaturated monocarboxylic acid of 3 to 5 carbon atoms the epoxy ring being reacted with an aliphatic polyamine containing at least one nontertiary amino group, the molar ratio of the oxirane portion to amino compound being approximately 1:1, said copolymer containing from about 0.05 to 8.0% by weight of nitrogen and having a total molecular Weight of at least about 2,000.

.The lubricant composition of this invention as described above is unusually etlective in the prevention of engine deposits. The detergent copolymer of the composition contains no metal component and is therefore substantially free of any ash-forming tendencies. This is a particular advantage over conventional detergent those encountered in diesel engines.

The essential component of the polymeric detergent of the lubricant composition as described above is the predominantly aliphatic hydrocarbon macromolecule having epoxy groups reacted with a single nontertiary amino group of an amino compound to yield an amino-alcohol group. The aliphatic hydrocarbon portion provides the oil-solubility to the copolymer, and the glycidyl-amino compound portion supplies the surface active detergent polarity to the polymer. These oil-solubilizing and polar portions combine in the macromolecule to give the detergent properties as noted above. 7

In the present description the term macromolecule is employed in its commonly accepted sense and refers to large molecules such as those synthesized by polymerization and condensation reactions as well as those occurring in nature, for example, the polysaccharides and the polypeptides illustrated by cellulose and proteins. Most suitably, the predominantly aliphatic hydrocarbon macromolecule detergent additive of the invention is a polymeric type compound. Such compounds may be prepared by first introducing epoxy groups or attaching oxirane groups to ethylene, propylene or isobutylene polymers by means of reactive centers which provide linking groups. Following this, the epoxy groups are reacted with the amino compounds. More satisfactorily for present purposes, however, such polymeric compounds are obtained by copolymerizing the appropriate oil-solubilizing and epoxy substituted monomers as hereinafter described, followed by reaction with the amino compound to give the oilsoluble polymer having the essential polar acting aminoalcohol groups.

The oil-solubilizing monomer portion of the polymeric additives of this invention can be any compound having a single polymerizable ethylenic group together with an oil-solubilizing hydrocarbon group of from 4 to 30 aliphatic carbon atoms. Such monomers are essentially characterized by their ability to copolymerize through said ethylenic group with monomers containing the intermediate epoxy groups or the polar-acting amino-alcohol group referred to above. Alternatively, the oil-solubilizing aliphatic radical can be introduced into the copolymer of the composition according to this invention following the polymerization. This aliphatic radical, whether pres ent in the original monomer or introduced into the copolymer imparts oil-solubility to the polymer. It is preferably a branched or straight chain alkyl radical or a cycloalkyl radical such as butyl, isobutyl, n-pentyl, decyl, dodecyL cyclohexyl, etc., or an alkenyl radical such as oleyl, ricinoleyl or the like wherein the ethylenic double bond has substantially no copolymerizing tendency.

Oil-solubilizing monomers of this general character are well known in the art and are frequently employed as the oil-solubilizing portion of copolymers which are added to lubricating oils to improve the viscosity index and pour ployed to form the copolymeric additives of the present invention include the following:

2-ethylhexene-l Diand triisobutylene Tripropylene p-Octylstyrene Vinyl cyclohexane p-Tertiarybutylstyrene ETHERS Vinyl n-butyl ether Vinyl Z-ethylhexyl ether Allyl n-butyl ether Allyl isobutyl ether Al'lyl cyclohexyl ether Allyl 4,4,8,8tetramethyl docosyl ether Methallyl n-hexyl ether Methallyl n-decyl ether Methallyl Z-ethylhexyl ether Methallyl octadecyl ether Propenyl 2-ethylhexyl ether Crotyl n-octyl ether Isopropenyl dodecyl ether l-decenyl butyl ether l-eicosenyl decyl ether Vinyl p-octylphenyl ether Methal'lyl p-tert. butylphenyl ether 1 decenyl p cetylphenyl ether 1 decenyl 2 phenylbutyl ether ESTERS Vinyl caproate Vinyl palmitate Vinyl oleate Allyl caprylate Allyl lau-rate Allyl oleate Allyl palmitate Allyl stear-ate Ally-l Z-ethylhexanoate Allyl ricinoleate Allyl esters of babassu acids Allyl esters of lard acids Allyl naphthcnate Methal-lyl caproate Methallyl naphthenate Methallyl ricinoleate Methallyl p-octylbenzoate Methallyl oleate Methallyl cyclohexane carboxylate Methallyl palmitate Crotyl oleate Cro-tyl naphthenate a-Methylcrotyl palmitate l-propenyl naphthena-te l-propenyl elaidate Dodecyl acrylate Hexadecyl methacrylate Isobutyl a-decylacrylate Vinyl p-n-octyl benzoate Ally 3,5-diisobutyl beni zoate Cyclohexyl methacryl-a-te Cyclohexyl 2-dodecenoate Although any of the oil-solubilizing compounds de-' Decyl vinyl acetate Isooctyl a-chloroacrylate p-Isoamylpheuyl 2-hexadecenoate 4-p-polylbutyl 2-octodecenoate Undecyl cinnamate Me'thylcyclohexyl 2-etzhyl-2- hexenoate S-ethyldooosyl crotonate Octadecyl isocrotonate n-B-utyl 2-eicosenoa-te p-Tert. amylphenyl octadecyl maleate p-Hexadecylphenyl 2 ethylhexyl maleate o-Tolyl 2 octadecylcyclohexyl maleate Butyl methacrylate o lonyphenyl hexadecyl maleate Dihexadecyl maleate Di methylcyclohexyl maleate Mono-2-ethylhexyl maleate Di-Z-ethylhexyl maleate Dl-dodecyl malea-te Di-dodecyl furnarate Di-dodecyl mesaconate Di-dodecyl citraconate o-Tolyl octadecyl itaconate Mono-hexadecyl it-aconate Isopropenyl palmito'leate l-decenyl la-urate l-hexadecenyl myristate scribed above will give effective copolymer compositions for lubricant compositions in accordance with the present invention, alkyl esters of a,/8-unsaturated monocarboxylic acids of from 3 to 5 carbon atoms having alkyl groups of at least 4 carbon atoms and, more particularly, of from 8 to 30 carbon atoms are most preferred both for availability'and effectiveness of copolymers prepared from them. Representative acids of this type are the acrylic, methacrylic, crotonic, tiglic, angelic, a-ethylacrylic, tic-methylcrotonic, a-ethylcrotonic, B-ethylcrotonic, fl-proplycrotont Amino ethyl ethanolamine N-amino ethyl stearyl imid-t Ethylene diamine I N,N-dimethyl propylene is, and hydrosorbic acids and the like. Even more deand mixtures thereof containing an average of from 10 to 20 carbon atoms in the alkyl groups, since they are'found to provide highly superior polymers for the lubricant compositions of the invention and are obtainable in commercial quantities. V

The epoxy substituted monomeric components of the additives of this invention as already mentioned are preferably derivatives of a polymerizable oxirane compound which is reacted with an amino, compound containing at least one nontertiary amino group. j Suitable epoxy substituted monomers includethe olefins', ethers and esters of the types mentioned above in connection ,Wiih-the oilsolubilizing monomers, the essential diiierence being that they are characterized by the presence of an epoxy group in addition to the polymerizableethylenic-group For present purposes the prefer-red epoxy compounds 7 are the above-mentioned-olefins, ethers and esters as illustrated by butadiene monoxide, .allyl glycidyl ether, vinyl glycidyl ether, glycidyl methacrylate,'diglycidyl maleate and the like. Such epoxy compounds whenyreacted with a single nontertia-ry amino group of an amino compound provide monomers having the following structure in addiin which R is hydroxyalkyl, aininoalkyl or polyalkylene polyamine in structure and R is hydrogen or a group similar to group R In the formulae R and R may also be present in the formof a single aromatic or cycloaliphatic ring as in the case of N-amino propyl morpholine, N-Z-a-mino ethyl piperazine, etc..

Presently preferred are the reactants of glycidyl esters of unsaturated monocarboxylic acids of 3 to 5 carbon atoms and aliphatic polyamines such as alkylene diamines and polyalkylene polyamines in which the alkylene groups contain from 2 to 4 carbon atoms each and the .polyalkylene polyamines contain from 2 .to 8 :alkylene amineunits. The amino groups of the polyamines may have nitrogen atoms substituted by alkyl radicals of from 1 to 4 carbon atoms, so long as there is at least one primary or secondary amino group present forreacting with the epoxy ring of the glycidyl group. Representative amino compounds which can be reacted with the epoxy ring or the oxirane group .as described above include: 7

ALIPHATIC AMINES N-oleamide of hydroxyethyl ethylene diamine Diethylene triamine Tetraethylene" pentamine diamine Ethanolamine Diethanolamine azoline AROMATIC AMINES Inprepa-ring the polymers=ofthe inventionit'is only necessary that conditions be chosen which ensure .polymerization and the formation of polymers having the req uisi'te oil -solu'bility andpol-arity. The :oil-solubilizing (A) monomers vary somewhat in their solubilizing char- Thuspin some casesvit is: possibleto obtain acteristics. polymers which are soluble in oil byemploying oil-solubilizing (A) and giycidyl-amino compoundv (B) monomer ratios as low as 1:1. In other cases it is advantageous t raise the ratio of '(A) to (B) to a much higher value, for example, about 100: 1 in order to obtain a polymer product having optimum oil-solubility and polarity characteristics. As a general rule, however, polymers having excellent dispersant characteristics together with the requisite oil-solubility (which should be at least 0.5 and is preferably as great as by weight of the lubricant composition) can be prepared by employing oil-solubilizing (A) monomers to polar (B) monomers in ratios of from about 5:1 to 1001-1 and such a range is preferably employed where possible.

Because of the variations in the types of oil-solubilizing (A) monomers and the polar (B) monomers as mentioned above, it is preferable to describe the overall composition of the polymers of this invention on the basis of amino nitrogen content of the (B) component. Suitable detergents or dispersants are obtained when this nitrogen content is from 0.05 to 8.0% by weight of the polymer. Preferably, the polymers contain from 0.1 to 5.0% by weight.

The macromolecules employed in the compositions of this invention can be prepared by any one of several methods as known in the art. As indicated above, the oilsolubilizing groups, the amino-alcohol groups and optional polar groups of the macromolecules are attached in various ways. In the case of the essential amino-alcohol groups there are three general methods of attachment. (1) The amino-alcohol group may be incorporated by reacting a preformed polymer containing reactive centers such as free carboxyl groups with glycidol following which the epoxy group of the glycidyl group is reacted with the amino compound. (2) The amino-alcohol group may also be introduced as the polymerizable monomer prepared by (a) reacting glycidol with a reactive monomer such as methacrylic acid which is then polymerized to give a glycidyl methacrylate containing copolymer in which the epoxy groups may be reacted with the amino compound or (b) reacting glycidol with a reactive monomer such as methacrylic acid followed immediately by reaction of the epoxy group of the glycidyl group with the amino compound to give the amino-alcohol group monomer which is then copolymerized with the oil-solubil-izing (A) and optional (C) polar monomers. (3) The amino-alcohol group may be incorporated into a preformed polymer by reacting an epoxy amino compound reaction product of the amino-alcohol group type mentioned above with reactive centers as described in (1). In this case the epoxy portion of the glycidyl group has already been reacted With the amino compound. Thus, it may be seen that one may polymerize a mixture of the desired monomer components to form the polymer or the copolymers may be obtained by starting with suitable precursor compounds with the desired monomer units and treating the intermediate to obtain the desired final product.

In all of the above general methods, when the oxirane ring is reacted with the amino compound, a large excess of amine is employed to prevent cross linking. When the oxirane ring is opened with an amino compound, a new amine and a free hydroxyl group are formed as follows:

(DH-0H R1 Er -rig E: R7 When R or R is hydrogen, these hydrogen atoms, as well as those of an other non-tertiary amino group are capable of opening :a second oxirane ring. This may result in cross-linked, resinous polymers. For example, in the case where the amino group is added to the monomer before polymerization (as in method 211 above) there would result a di-ethylenical'ly unsaturated monomer which would necessarily cross link during polymerization. To avoid these undesirable reactions, and ensure readily cross-linked primary amino and polyamino compounds.

When the polymeric additive of this invent-ion, or a suitable polymeric intermediate, is to be prepared by reaction of monomeric components, said polymers can be prepared by conventional bulk, solution or emulsion methods in the presence of an addition polymerization initiator.

Preferably, however, the copolymerization is eifected in an inert organic solvent such as benzene, toluene, xylene or petroleum naphtha in the presence of a free radical-liberating type of initiator such as a peroxy compound, for example, benzoyl peroxide, acetyl peroxide, tert. butyl hydroperoxide, di-tert. butyl peroxide, di-benzoyl peroxide, or d-i-tert. amyl peroxide, or an azo initiator such as l,l'-razodicyclohexane, carbonitrile or 0c,oc'- azodiisobutyronitrile. The catalyst, or polymerization initiator, can be employed in an amount of from about 0.01 to 10%, with a preferred range being from 0.0 1 to 2%. If desired, the catalystcan be added in increments as the reaction proceeds. Likewise, additional portions of the solvent can also 'be added from time to time in order to maintain the solution in a homogeneous condition. The temperature of copolymerizat-ion varies from about to 300 F. with the optimum temperature for any given preparation depending on the nature of the solvent, the concentration of monomers present in the solvent, the catalyst and the duration of the reaction. Much the same conditions are employed when the copolymerization is effected in bulk rather than in the presence of an inert solvent.

The additives of this invention have apparent molecular weights as determined by standard light scattering methods and viscosity measurements of at least 2,000 and preferably at least 50,000. For practical purposes molecular weights of from 100,000 to 1,000,000 are most suitable from the standpoint of viscosity and other physical characteristics of the polymeric additives.

The following examples are illustrative of typical methods for preparing the alcohol-amino compound poly meric type additives according to the invention.

Example 1 This example illustrates the preparation of a copolymer intermediate of mixed dodecyi and octadecyl methac-rylates with glycidyl methacrylate.

A 2-(liter flask fitted with stirrer, reflux condenser and dropping funnel is charged with 750 g. (2.5 moles) of alkyl methacrylate in which the alkyl groups are a mixture of 60% by weight dodecyl and 40% by weight octadecyl groups, 14.2 g. (0.1 mole) glycidyl methacrylate and 510 g. benzene. The flask is purged with nitrogen. The charge mixture is heated to reflux and is polymerized for about 7 hours by the addition of a 2% solution of bis-azoisobutyronitrile in benzene as catalyst. The catalyst is added at a rate of 3. 8 ml. every 15 minutes.

The polymer formed in the above reaction is precipitated from the reaction mix by the addition of a fourfold volume of acetone. The yield of polymer is 690 g. which is equivalent to 90.3% of theoretical based on the reactants. A determination of the oxirane oxygen of the epoxy groups in the glycidyl portion was made of the product in the acetone phase. This determination indicates the presence of 1. 5 g. or 10.5% by weight of glycidyl methacrylate. Accordingly, the alkyl methacrylate and glycidyl methacrylate are present in a 25:1 mole ratio.

Example 2 This example shows the conversion of the alkyl methacrylate and glycidyl methacrylate copolymer intermediate of the above preparation to glycidyl-amino compound.

In a 2-liter flask, as described above, 76 g. of the copolymcr of Example 1 is dissolved in 200 of xylene. This solution is refluxed for 5 hours with 20, g. N,'N dimethyl 1,3 propane diamine. The polymeric product is precipitated from xylene solution three times.

can be imparted to lubricating oils by dissolving therein 1 a quantity of from about 0.1 to 10% by weight of the. polymers of the type described above, although a pre- 1 ferred range is from about 1 to 5% by weight. Onthe other hand, since the polymers of this invention are unusually compatible with mineral and other lubricating oils in substantially all proportions, as much as 75% of the present polymer additives can be dissolved in a suitable lubricating oil for the purpose of preparing a concentrate capable of dilution with lubricating oils and the like to preparethe final lubricant composition. Suchconcentrates, which may also contain other additives in desired amounts, and which normally contain at least 10% of the polymer, comprise a convenient method for handling the polymer and may be used as a compounding agent for lubricants in general.

The polymeric additives of this invention can be used with good effect in the case of any one of a wide variety of oils of lubricating viscosity, or of blends of such oils. Thus, the base oil can be a refined Pennsylvania or other paraifin base oil, a refined naphthenic base oil, or a syn thetic hydrocarbon or nonhydrccarbon oil of lubricating viscosity. As synthetic oils there can be mentioned alkylated waxes and similar alkylated hydrocarbons of rela-' tively high molecular weight, hydrogenated polymers of hydrocarbons, and the condensation products of chicrinated alkyl hydrocarbons with aryl compounds. Othersuitable oils are those which are obtained by polymerization of lower molecular weight alkylene oxides such as propylene and/or ethylene oxide. Still other synthetic oils are obtained by etheriiication and/or esterification of the 'hydroxy groups in alkylene oxide polymers such as, for example, the acetate of the Z-ethylhexanoh.

initiated polymer of propylene oxide. Other important classes of synthetic oils include the various esters as, for example, di-(2-ethylhexyl)sebacate, tricresyl phosphate and silicate esters. If desired, the oil can be a mixture.

of mineral and synthetic oils.

While satisfactory lubricant compositions can'be obtaincd by adding to the base ,oil employed only oneor more of the polymeric additives of the typedescribed above, it also falls within the purviewof this invention to provide lubricant compositionswhich contain not only such polymers, but also other additives such as pour point depressants, oiliness and extreme pressure agents, anti-oxidants, corrosion inhibiting agents,

blooming agents, thickening agents and/ or compounds for enhanc- 8 Y of ,copolymer employed is:,relatively small) :of auxiliary detergents and/or antiwear agents."

Illustrative lubricant compositions of the above type containing the copolymeric additives of the invention in combination with other agents may include, for example, from about 0.1 to 10% byweight of alkaline, earth metal higher alkylphenate detergent and Wear reducing agents such as calcium alkylphenates having an averageof approximately 14 carbon atoms in the alkyl group as well as organic thiophosphate'corrosionand high temperature oxidation inhibitors such as the reaction product of pinene and P 8 and the bivalent metal dihydrocarbyl dithiophosphates, zinc butyl hexyl dithiophosphate and zinc tetradecylphenyldithiophosphate in amounts of, from about 0.1 to 10% by weight of the composition. 'Temperature-viscosity improving agents which maybe employed in the compositions, usually, in amounts of from about 1 to 10%, by weight, include-by Way of example the homopolymers of alkyl methacrylates such as the dodecylmethacrylate polymers known to the trade as 'Acryloid 710 and Acryloid 763, products of Rohm & Haas Company, and high molecular weight 'butenepolymers such as Paratone EN] 15F, a product of the Enjay Com The polymeric additives of, theinvention as described above are evaluated as detergents in lubricating oils and as dispersants in hydrocarbon liquids in a number of tests. The results of the tests along with a' description of the polymeric additives are set out in the following tables.

In the tests as described below the base oil, unless otherwise specified, is a solvent refined Waxhfree 150 Neutral mineral lubricating oil. It has a viscosity index of 88 and is derived from California waxy crude. The polymeric additive is employed in theoil in an amount of 2.8% by weightof polymer based on total composition, unless otherwise noted. f1

In the test Where the piston varnish'ratings are obtained, a given lubricatingoil'composition'is tested as the crankcase lubricant in a16-cylinder Chevrolet engine using a low grade gasoline especially prone to cause engine deposits, theconditions being those'defined in the standard FL-2 test procedureas described in the June 21, 1948, report of the Coordinating Research Council. This procedure requires the maintenance of a jacket temperature of F. and a crankcase oil temperature of 155 F. at 2500 rpm. and 45 brake horsepower of 40 hours, and therefore closely simulates'the relatively cold engine conditions which'are normally experienced in city driving. At the end of each test, the engine is dismantledand the amount of engine deposits on the piston determined and expressed as the piston varnish rating. This value is obtained by visuallylrating (on a scale of O to 10, with 10 representing the, absence of any deposit) the amount of deposit on each piston skirt and averaging the individual ratings so obtained for the various pistons. Under the conditions of. this test, a piston varnish rating of 3.5 is indicative of detergent performance, though preferably this rating should be 4 or above. In the case of the base oil alone without the addition of any additives it is found that the piston varnish rating is approximately 3L0. On the other hand, as indicated by the data presented in the tables below, when the base oil is compoundedwith the indicated amounts of a copolymen'grcatly superior results are obtained.

The polymeric additives according to the invention are alsoevaluatcd for their dispersing properties in the stand:

. ard Carbon Peptization Test. Inthistest 0.1 g. of;

active copolymer is dissolved in '1 00 ml. of kerosene in a 100 ml. graduated glass cylinder. .To this solution of polymer is. added 0.5 g. of ordinary" lamp black. The contents of the graduated cylinder are mixedrby manual shaking using an end-over-end motion for exactly one minute. After the shaking, the cylinder isplaced upright and observed periodicallyabout every half hour.

9 The Carbon Peptization Test number (CPT) is expressed as hours required for total settling of the carbon black.

4, 8 and 11 contain no amino compound, as indicated in the table.

TABLE I Molar Ex. No. Amino Compound or (B) @23 Percent v.r PD No. (L-l) PVR CPT Monomer mers N (FL-2) (Hours) 88 800, 800, 800 3.0 1 8 2 Di-n-hexly-amine 22 Ethanolamine N-amino ethyl ethanolamtne 48 None 1 Dimethyl amino propylarnine-.. 2 24 Tetraethylene pentamine 3g 6 8 30 Tetraethylene pentamine 17 A CPT of 4 hours or more indicates significant dispersing properties. The Carbon Peptization Tests are found to correlate well with the FL-2 engine test described above.

In addition to the foregoing tests of detergency and dispersing properties of the polymeric additives data were also obtained in a Caterpillar L-l test under Supplement I conditions for a period of 120 hours as described in the Coordinating Research Council Handbook, January 1946.

In Table II below, additional examples are given to show several typical variations of the primary components of the novel amino-alcohol copolymers according to this invention. Different oil-solubilizing monomers are included and the characteristic amino-alcohol groups are incorporated in a variety of forms, such as those derived from olefins and others. The effectiveness of the copolymers is illustrated by their Carbon Peptization Test In these tests the PD numbers of oils are obtained to number.

TABLE II Molar Ex. No. Oil-Solubllizing (A) Monomer Alcohol-Amino (B) Monomer Ratio of Percent CPT Mono- N (Hours) mers 607 Dodecyl methacrylate Allyl glycidyl ether-Tetra 1G gotadeclyl mgilthaerlylatenh ieatfiyhnie ptcelntlarillilne.3 4 18 6 odecy met acry ate y g yci y e er- 17 {407; Octadecyl methacrylate"... }Diamino toluene. 70/1 5 18 {60% Dodecyl methacrylate Butadiene monoxide- 19/1 0 48 7 octadecyl methacrylate. Z-Amino ethyl piperazine. 19 {60% Dodecyl methacrylate }Butadiene monoxide- 10 1 3 8 40% Octadeeyl methaerylate.. Diethylene triamine. 2Q Vinyl tmrq to Allyl glycidyl ether-Dimethyl 20/1 0. 43 16 1 t Atl i t li i tt ii n1 1 7 Vin yace a.e y gyei y e erthe y 21 {50 Didodecyl maleate amino propylamine. 32/1 18 16 show the piston discoloration rating. Following each engine test the three piston lands are examined visually. A piston land which is completely black is assigned a PD number of 800. The piston lands which are completely clean are assigned a PD number of 0. Intermediate PD numbers are assigned in proportion to the extent and degree of discoloration of the piston lands.

In Table I below the polymers all contain a representative oil-solubilizing (A) monomer consisting of 60% by weight dodecyl methacrylate and 40% by weight of octadecyl methacrylate. The glycidyl component of the (B) monomer in the polymer is glycidyl methacrylate, which is also representative of such components. In the examples of the table a variety of amino compounds are shown which are reacted with the epoxy group of the glycidyl methacrylate. The polymers of the examples also are identified by their monomer ratios, as well as by analysis for nitrogen on a percent by weight basis (percent N). The Viscosity Index of the oils in the examples is also shown in the table as evidence of the important viscosity-temperature characteristics of the lubricant compositions containing polymers according to this invention.

In the examples of the table the performance of the base oil alone, without any polymers whatsoever, is shown as Example No. 3. The copolymers of Examples Nos.

From the tests of the foregoing tables it will be seen that each of the illustrative compositions containing the polymeric lubricating oil additives according to the invention possesses greatly improved lubricating properties compared to the base oils alone, or oils containing other closely related copolymers. The copolymeric additives containing alcohol-amino constituents are remarkably effective detergents and dispersants. Significant benefits are obtained in both low temperature type of engine operation as found in gasoline internal combustion engines and in high temperature type of operation as found in diesel engines. temperature detergent and dispersant properties in lubricant compositions containing a single polymeric additive is particularly important. The presence of both desirable properties in a single polymeric additive facilitates the provision of a single lubricating oil composition suitable for use in either gasoline engine lubricating oils or diesel engine lubricating oils.

We claim:

1. A detergent oil-soluble copolymer of (A) at least one alkyl methacrylate having 8 to 30 carbon atoms in the alkyl group and (B) glycidyl methacrylate, the mole ratio of (A) to (B) being from about 5:1 to :1, said polymer being reacted with N-aminoethyl ethanolamine, the molar ratio of the glycidyl portion to N-aminoethyl The combination of such low and high 7 ethanolamine being approximately l'zl, said copolymer containing from about 0.05 to 8% by weight of nitrogen and having a total molecular Weight of at least about 2000, said copolyrner being characterized by a solubility in mineral lubricating oil of at least 0.5% by weight.

2. A lubricant composition comprising a major portion of an oil of lubricating viscosity and a minor portion suflicient to enhance the detergent characteristics of the composition of the detergent oil-soluble copolymer of claim 1.

References 'Cited by the Examiner UNITED STATES PATENT S V Lippi-ncott et a1. 252--56 Catlin 252-515 Payne et al. 260-348 Cupery 260-851 Blake 260-861 10 DANIEL E. WYMAN, Primary Examiner.

Claims (2)

1. A DETERGENT OIL-SOLUBLE COPOLYMER OF (A) AT LEAST ONE ALKYL METHACRYLATE HAVING 8 TO 30 CARBON ATOMS IN THE ALKYL GROUP AND (B) GLYCIDYL METHACRYLATE, THE MOLE RATIO OF (A) TO (B) BEING FROM ABOUT 5:1 TO 100:1, SAID POLYMER BEING REACTED WITH N-AMINOETHYL ETHANOLAMINE, THE MOLAR RATIO OF THE GLYCIDYL PORTION TO N-AMINOETHYL ETHANOLAMINE BEING APPROXIMATELY 1:1, SAID COPOLYMER CONTAINING FROM ABOUT 0.05 TO 8% BY WEIGHT OF NITROGEN AND HAVING A TOTAL MOLECULAR WEIGHT OF AT LEAST ABOUT 2000, SAID COPOLYMER BEING CHARACTERIZED BY A SOLUBILITY IN MINERAL LUBRICATING OIL OF AT LEAST 0.5% BY WEIGHT.

2. A LUBRICANT COMPOSITION COMPRISING A MAJOR PORTION OF AN OIL LUBRICATING VISCOSITY AND A MINOR PORTION SUFFICIENT TO ENHANCE THE DETERGENT CHARACTERISTICDS OF THE COMPOSITION OF THE DETERGENT OIL-SOLUBLE COPOLYMER OF CLAIM 1.