| 主权项 |
1. A lubricating composition comprising an oil of lubricating viscosity, a polyisobutylene succinimide dispersant, a dispersant viscosity modifier and an amine-functionalised additive,
wherein the polyisobutylene succinimide dispersant is derived from a polyisobutylene having a molecular weight or 750 to 2500, wherein the amine-functionalised additive is derived from an amine having at least 3 aromatic groups, wherein the amine-functionalised additive is a product obtained by reacting the amine having at least 3 aromatic groups with a carboxylic functionalised polymer, and wherein the dispersant viscosity modifier is either: prepared by grafting of an olefinic carboxylic acid acylating agent onto a polymer of 15 to 80 mole percent of ethylene, from 20 to 85 mole percent of C3-10 alpha monoolefin, and from 0 to 15 mole percent of non-conjugated diene or triene, said polymer having an average molecular weight ranging from 5000 to 500,000, and further reacting said grafted polymer with an amine, or a reaction product of: (a) a polymer comprising carboxylic acid functionality or a reactive equivalent thereof, said polymer having a number average molecular weight of greater than 5,000; and (b) an amine component comprising at least one aromatic amine containing at least one amino group capable of condensing with said carboxylic acid functionality to provide a pendant group and at least one additional group comprising at least one nitrogen, oxygen, or sulfur atom, wherein said aromatic amine is selected from the group consisting of (i) a nitro-substituted aniline, (ii) an amine comprising two aromatic moieties linked by a —C(O)NR— group, a —C(O)O— group, an —O— group, an —N═N— group, or an —SO2— group where R is hydrogen or hydrocarbyl, one of said aromatic moieties bearing said condensable amino group, (iii) an aminoquinoline, (iv) an aminobenzimidazole, (v) an N,N-dialkylphenylenediamine, and (vi) a ring-substituted benzylamine. |
