VISCOSITY INDEX IMPROVER AND LUBRICANT COMPOSITION CONTAINING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a viscosity index improver capable of forming a lubricant composition high in viscosity index, excellent in low temperature fluidity and low in dielectric constant.SOLUTION: There are provided a viscosity index improver containing a polymer (A) containing (meth)acrylate (a) having a cycloalkyl group of which at least one hydrogen atom is substituted by a substituent represented by the general formula (1) as a constituent monomer, and a lubricant composition containing the same. The general formula (1) is: -(CH)m-O-R, where m is an integer of 0 to 1 and Ris an alkyl group having 1 to 22 carbon atoms.