COPOLYMERS AND LUBRICANT COMPOSITIONS CONTAINING THEM

摘要

1333733 Unsaturated ester copolymers SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 19 Nov 1970 [21 Nov 1969] 55030/70 Heading C3P [Also in Division C5] Copolymers comprising units of an ester of an olefinically unsaturated carboxylic acid and an alcohol containing at least 8 carbon atoms, the copolymers having a weight average molecular weight/number average molecular weight ratio of below 4À5, may be prepared by copolymerizing the esters in the presence of at least one free radical initiator and at least one chain transfer agent. Specified acids are maleic, fumaric, mesaconic, citraconic, itaconic, crotonic, tiglic, angelic, acrylic and methacrylic acids, and preferred alcohols are primary C 10-22 alcohols with unbranched chains. Preferred comonomers contain polar groups and may be other esters of the class defined, vinyl chloride, N-vinyl pyrrolidone, 2-methyl-5-vinyl pyridine, 4 - vinyl pyridine, N,N - diethyl - #- aminoethyl methacrylate, N,N-dimethyl-#- aminoethyl methacrylate or #-hydroxyethyl methacrylate. Polymerization may be effected in bulk or emulsion, or preferably in solution, e.g. in benzene, toluene or mineral oil; preferably in the presence of at least two free radical initiators, the decomposition rates of which' differ at the polymerization temperature by a factor of at least 3. The products are useful as lubricant additives, optionally after chemical reaction, e.g. with amines, alcohols or epoxides, to introduce desirable groups. Examples describe the copolymerization of methacrylic acid, stearyl methacrylate and C 12-15 alkyl methacrylates in a mixture of toluene and methanol in the presence of benzoyl peroxide or mixture thereof with lauroyl peroxide using dodecyl mercaptan as chain transfer agent, and conversion of the products to glycol monoesters by reacting with ethylene oxide in the presence of lithium hydroxide.