| abstract |
Hydrocarbyl substituted C4 to C10 monounsaturated dicarboxylic acid, anhydrides or esters, e.g. polyisobutenyl succinic anhydride, preferably made by reacting polymer of C2 to C10 monoolefin, preferably polyisobutylene, having a molecular weight of about 1500 to 5,000, preferably with a C4 to C10 monounsaturated acid, anhydride or ester, preferably maleic anhydride, such that there are 1.05 to 1.25 dicarboxylic acid producing moieties per molecule of said olefin polymer used in the reaction mixture. The resulting materials are useful per se as oil additives, or may be further reacted with amines, alcohols, amino alcohols, boric acid, etc. to form dispersants. |