| abstract |
A process for preparing an oligomeric copolymer of an unsaturated acidic reactant and a high molecular weight olefin having a sufficient number of carbon atoms such that the resulting copolymer is soluble in lubricating oil and wherein at least 20 weight percent of the total olefin comprises an alkylvinylidene isomer, which process comprises reacting the high molecular weight olefin with the unsaturated acidic reactant in the presence of a free radical initiator and a solvent selected from:n (a) polyisobutenyl succinic anhydride (PIBSA), (b) polyPIBSA, or (c) a mixture comprising polyisobutene and a copolymer prepared by reacting a high molecular weight olefin, wherein at least 20 weight percent of the total olefin comprises an alkylvinylidene isomer, and an unsaturated acidic reactant in the presence of a free radical initiator. |