摘要 |
Graft copolymers useful as a dispersant-viscosity improver for lubricating oil compositions comprise a hydrocarbon polymer having graft polymerized thereon at least two nitrogen containing units, at least one of the nitrogen containing units being derived from at least one of a neutral N-(lower hydrocarbyl group)- (meth)acrylamide and a neutral N,N-di-(lower hydrocarbyl group)- (meth)acrylamide, wherein the total number of carbon atoms in the lower hydrocarbyl groups does not exceed 9, and at least one of the nitrogen containing units being derived from at least one vinylic nitrogen containing heterocyclic compound.
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