Patent ID: 9481849
Filing Date: 2016-11-01
CPC Classification: C08F,C10M,C10N

Claim Text:
1. A polymer, comprising: at least 10% by weight, based on a total weight of the polymer, of units derived from one or more ethylenically unsaturated ester compounds of formula (I): from 20 to 55% by weight, based on the total weight of the polymer, of units of one or more ethylenically unsaturated ester compounds of formula (II):  and from 20 to 40% by weight, based on the total weight of the polymer, of units of one or more ethylenically unsaturated ester compounds of formula (III): wherein R is hydrogen or methyl, R R R R R R wherein units derived from ethylenically unsaturated ester compounds of formula (II)are a mixture, and the mixture comprises as R units having a 2-methyl branched alkyl residue, and units having a 2-ethyl branched alkyl residue, and/or units having a 2-propvl branched alkyl residue, and units having a 2-butvl or hiaher branched alkyl residue, a weight ratio of total units of the one or more ethylenically unsaturated ester compounds of formula (II) to total units of the one or mor e ethylenically unsaturated ester compounds of formula (III) is from 4:1 to 1:1 and the polymer is suitable as a viscosity index improver.