Patent ID: 8513172
Filing Date: 2013-08-20
Classification: C08F,C08L,C10M,C10N

Abstract:
1. A process for preparing a polymer and a lubricating composition thereof, comprising the steps of: (1) contacting: wherein the process of step (1) is a controlled radical polymerisation process with living characteristics; and at least about 50% of the polymer chains from step (1) contain a reactive end group capable of reacting with a polyvalent coupling agent; (2) contacting the polymer prepared by step (1) with a polyvalent coupling agent to form a star-polymer, wherein the star-polymer is a block-arm star polymer or a hetero-arm star polymer; and wherein the star polymer is derived from at least two monomers comprising: and wherein the star-polymer has about 2 to about 50 arms present on the star polymer; (3) optionally contacting the polymer prepared by step (1) or step (2) with a polymerisation inhibitor; and (4) mixing the polymer prepared by step (2) or step (3) with an oil of lubricating viscosity to form a lubricating composition.