Patent ID: 9080124
Filing Date: 2015-07-14
Classification: C08L,C10M,C10N

Abstract:
1. A method for reducing wear in lubricant oil compositions, comprising: adding a graft copolymer to at least one lubricant oil; wherein the graft copolymer comprises at most 200 ppm of sulfur and the graft copolymer is obtained by a two-stage polymerization, comprising: free-radically polymerizing a monomer composition A) to prepare a graft base; and graft polymerizing a monomer composition B) on the graft base; wherein the monomer composition A) comprises: wherein the monomer composition B) comprises from 70 to 100% by weight of N-vinyl pyrrolidone, wherein the ratio of the weight of the monomer composition A) to the weight of the monomer composition B) is in the range from 99.7:0.3 to 80:20, and wherein a graft yield is greater than or equal to (x* 10−