Patent GB-787057-A (GB)
Title: Polymeric additive and lubricant composition containing it
IPC: C10M159/00
Filed: 1955-05-23
Abstract: Lubricating compositions comprise a major proportion of a lubricating oil and a minor proportion of a copolymer which comprises in combined form units of (a) an alkyl ester of an aliphatic C3-C15 alpha, beta-unsaturated monocarboxylic acid in which the alkyl group contains from 4 to 30 carbon atoms, (b) an ester of type (a) in which the alkyl group contains a different number in the range of 4 to 30 carbon atoms, (c) an aliphatic C3-C15 alpha,beta-unsaturated monocarboxylic acid and (d) an ester of a poly-1,2-alkylene glycol having a molecular weight between 106 and 10,000 and an aliphatic C3-C15 alpha,beta-unsaturated monocarboxylic acid, the copolymer having a molecular weight of at least 2000. Components specified are: (a) and (b) butyl and stearyl acrylates, butyl, lauryl, oxotridecyl, cetyl, stearyl, hexadecyl and octacosyl methacrylates, iso-octyl chloracrylate, tricosyl alphaethylcrotonate, triacontyl tiglate and pentadecyl angelate, (c) acrylic, methacrylic, crotonic, tiglic, angelic, alpha-ethyl acrylic and alpha-methyl, alpha-ethyl, beta-ethyl and alpha-butyl crotonic acids, and (d) esters of diethylene pentaethylene, nonaethylene and tetra-1,2-propylene glycols, the monobutyl ether of heptaethylene glycol, the tridecyl ether of decaethylene glycol, polymers of ethylene oxide and 1,2-propylene oxide and the lauryl ether of polyethylene glycol with acids such as acrylic and methacrylic acids.  The formul  of other suitable glycols are provided including those substituted by carboxyl, ester, hydroxyl, nitro, mercapto, amino or amido groups. Lubricating oils specified are hydrocarbon oils and synthetic oils such alkylene oxide polymers, e.g. polypropylene oxide, and derivatives thereof, dibutyl adipate, di - 2 - ethylhexyl sebacate, di-n-hexyl fumarate, di-lauryl azelate, tetradecyl benzene, tricresyl phosphate, diethyl esters of decane phosphonic acid, polymethyl siloxane, polymethylphenyl siloxane, polymethoxyphenoxy siloxane, tetra-2-ethylhexyl silicate and tetra-p-tert-butyl phenyl silicate. Specification 768,690 is referred to.ALSO:An oil-soluble copolymer comprises in combined form units of (a) an alkyl ester of an aliphatic C3-C15 alpha,beta-unsaturated monocarboxylic acid in which the alkyl group contains from 4 to 30 carbon atoms, (b) an ester of type (a) in which the alkyl group contains a different number in the range of 4 to 30 carbon atoms, (c) an aliphatic C3-C15 alpha,beta-unsaturated monocarboxylic acid and (d) an ester of a poly-1,2-alkylene glycol having a molecular weight between 106 and 10,000 and an aliphatic C3-C5 alpha,beta-unsaturated monocarboxylic acid, the copolymer having a molecular weight of at least 2000. Components specified are: (a) and (b) butyl and stearyl acrylates, butyl, lauryl, oxotridecyl, cetyl, stearyl, hexadecyl and octacosyl methacrylates, iso-octyl chloracrylate, tricosyl alpha-ethylcrotonate, triacontyl tiglate and pentadecyl angelate, (c) acrylic, methacrylic, crotonic, tiglic, angelic, alpha - ethylacrylic, alpha - methylcrotonic, alpha - ethylcrotonic, beta - ethylcrotonic and alpha-butylcrotonic acids, and (d) esters of diethylene, pentaethylene, nonaethylene and tetra-1,2-propylene glycols, the monobutyl ether of heptaethylene glycol, the tridecyl ether of decaethylene glycol, polymers of ethylene oxide and 1,2-propylene oxide and the lauryl monoether of polyethylene glycol with acids such as acrylic and methacrylic acids.  The formul  of other suitable glycols are provided, including those substituted by carboxyl, ester, hydroxyl, nitro, mercapto, amino and amido groups. The copolymers may be prepared by the copolymerization of the four components in bulk, emulsion or solution in a solvent such as mixed hexanes, in the presence of catalysts such as benzoyl, acetyl, di-tert.-butyl or di-tert.-amyl peroxide, tert.-butyl hydroperoxide or an azo initiator such as 1,11-azocyclohexanecarbonitrile or azodiisobutyronitrile. During polymerization additional catalyst and solvent, if employed, may be added as the reaction proceeds. Alternatively, the copolymers may be prepared by after-treatment of an intermediate polymer, e.g. a copolymer of the (a), (b) and (c) components may be partially esterified with a polyglycol, or polydodecylmethacrylate may be partially hydrolysed and then partially re-esterified with a different alkyl alcohol and a polyglycol.  The copolymers are used as additives to lubricating oils.  Specification 768,690 is referred to.