Patent GB-759517-A (GB)
Title: Lubricant composition
IPC: C10M149/06
Filed: 1953-11-26
Abstract: An oil-soluble copolymer is obtained by copolymerizing (A) a compound having an ethylenic linkage and a group of from 4 to 30 aliphatic carbon atoms; and (B) an amide or imide of an a ,b -unsaturated carboxylic acid of from 3 to 6 carbon atoms, the copolymer comprising 1 to 15 monomer units of (A) for each monomer unit of (B).  Amides specified are acrylamide, methacrylamide, crotonamide, tiglamide, angelamide, a -ethacrylamide, a -methacrylamide, hydrosorbamide, maleimide, maleamide, maleamic acid, fumarimide, fumaramide, fumaramic acid, ethyl and dodecyl maleamates, octyl fumaramate, dodecyl maleamide, mesaconamide, 2-ethylhexyl citraconamate, itaconamide, benzyl and phenyl maleamates and benzyl citraconamate. Monomer (A) may be an olefin, ether, ester, ketone, aldehyde or diene (e.g. 2-hexadecylbutadiene-1,3) and lists are given.  Preferably a C8 to C30 alkyl ester of an unsaturated mono- or dicarboxylic acid is used. Oil-solubilizing radicals may also be introduced by esterification of copolymers derived from the corresponding unsaturated acids or alcohols.  The copolymers may be prepared in bulk or emulsion but preferably in solution, e.g. in benzene, toluene, xylene or petroleum naphtha.  Catalysts which may be used are benzoyl, acetyl, dibenzoyl, di-t-butyl and di-t-amyl peroxides; t-butyl hydroperoxide; azodicyclohexanecarbonitrile and azodi-isobutyronitrile.  The catalyst, solvent or monomer (see Example (2)) may be added incrementally during the reaction.  The copolymers may be added to natural or synthetic lubricating oils, e.g. in 0.1 to 10 per cent by weight, to impart detergent and anti-wear properties.  Conventional lubricating additives including metallic detergents may also be present.  Examples describe terpolymers and tetrapolymers and illustrate termination of polymerization at a definite stage.ALSO:A lubricating composition comprises a major proportion of an oil of lubricating viscosity and a minor proportion of a copolymer of (A) an ethylenic compound having a C4 to C30 aliphatic carbon group and (B) an amide or imide of an a , b - unsaturated carboxylic acid of from 3 to 6 carbon atoms; said components being in the ratio of 1 to 15 monomer units of (A) to each monomer unit of (B) (see Group IV(a)).  The lubricating oil may be a paraffin base oil such as refined Pennsylvania, or a synthetic oil such as alkylated hydrocarbons (waxes in particular), hydrogenated hydrocarbon polymers, condensation productions of chlorinated alkyl hydrocarbons with aryl compounds and polymers of propylene and/or ethylene oxide and esters or ethers thereof (e.g. the acetate of polymerized propylene oxide). Other oils which may be used are di(2-ethylhexyl) sebacate, tricresyl phosphate and silicate esters. The composition may also contain pour point depressants, oiliness and extreme pressure agents, antioxidants, corrosion inhibitors, blooming agents, thickening agents, viscosity improvers and auxiliary detergents or anti-wear agents.  The efficacy of the copolymers as detergents and anti-wear agents is illustrated by examples IV to XV wherein he results of testing various copolymer/wax-free California oil compositions are set out.