Dispersant Viscosity Modifiers

摘要

The disclosed invention relates to a composition comprising a grafted polymer. The polymer comprises a backbone with at least one olefin block and at least one vinyl aromatic block. The polymer is grafted with a pendant carbonyl containing group, the grafting being conducted by halogenating the vinyl aromatic carbon of the vinyl aromatic block and then grafting a carboxylic acid or derivative thereof on the halogenated vinyl aromatic carbon in the presence of an activating agent. The carbonyl containing-group is optionally substituted to provide ester, imide and/or amide functionality. The grafted polymer is useful as a dispersant viscosity modifier in lubricating compositions such as engine oils.