Copolymers and their manufacturing methods, resin compositions and resin molded articles

Abstract

The object of this invention is to provide copolymers with excellent formability and high refractive index. This invention is a copolymer comprising structural units (A) derived from chain olefins and structural units (B) derived from cyclic olefins, wherein the cyclic olefins are compounds of a specified formula (I), and the copolymer has a weight-average molecular weight of 20,000 or more and 250,000 or less.