METHOD FOR PREPARING COPOLYMER OF NORBORNENE MONOMERS AND POLAR VINYL OLEFIN MONOMERS, COPOLYMERS PREPARED BY THE METHOD, AND OPTICALLY ISOTROPIC FILMS COMPRISING THE COPOLYMER

摘要

A copolymer is provided to reduce the process costs in manufacturing, by manufacturing the copolymer with high polymerization rate at a low polymerization temperature. A method for preparing copolymer comprises a step for contacting a norbornene-based monomer and polar vinyl olefin-based monomer with a catalyst system including a radical initiator consisting of (i) a Lewis acid, (ii) an azo compound of the chemical formula 1: A1-N=N-A2, and (iii) a peroxide compound of the chemical formula 2: B1-O-O-B2; and a step for polymerizing it at 0 - 65‹C. The thickness-directional phase difference(Rth) value in the formation of a film is 1nm/mum or less.