Patent ID: 8557753

Claim:
A lubricating composition comprising an oil of lubricating viscosity and an amine-functionalised additive, wherein the amine-functionalised additive is derived from an amine having at least 4 aromatic groups, at least one —NH 2 functional group, and at least 2 secondary or tertiary amino groups, wherein the amine-functionalised additive is a product obtained by reacting the amine having at least 4 aromatic groups, at least one —NH 2 functional group, and at least 2 secondary or tertiary amino groups with a carboxylic functionalised polymer, wherein the amine having at least 4 aromatic groups, at least one —NH 2 functional group, and at least 2 secondary or tertiary amino groups is represented by the formula: wherein independently each variable, R 1 is hydrogen or a C 1-5 alkyl group; R 2 is hydrogen or a C 1-5 alkyl group; U is an aliphatic, alicyclic or aromatic group, with the proviso that when U is aliphatic, the aliphatic group may be linear or branched alkylene group containing 1 to 5-carbon atoms; and w is 1 to 10, and wherein the carboxylic functionalised polymer is a polyisobutylene-succinic anhydride polymer, a maleic anhydride-styrene copolymer, an ester of a maleic anhydride-styrene copolymer, an alpha olefin-maleic anhydride copolymer, or a maleic anhydride graft copolymer of (i) a styrene-ethylene-alpha olefin polymer, (ii) a hydrogenated alkenyl aryl conjugated diene copolymer, (iii) a polyolefin, or (iv) a hydrogenated isoprene polymer, or mixtures thereof.