Patent ID: 7468417

Claim:
A method of preparing cyclic olefin copolymer by ROMP in the presence of a non-polar solvent, a molecular weight regulator compound and a catalyst, in which the catalyst is a complex prepared by mixing a W salt compound and an organoaluminum halide compound and the composition of cyclic olefin compound forming a copolymer is regulated as indicated in Empirical Formula 1 to control gel content, as follows: (Empirical Formula 1) Norbornene=30˜70 weight %, Cyclic olefin compound=70˜30 weight %; wherein the cyclic olefin compound presented in Empirical Formula 1 is one or more compounds selected from a group consisting of dicyclopentadiene and other compounds represented by the following Formula 1: wherein, m is an integer of 0-1, R 1 is C 1 -C 5 alkyl and R 2 is H or C 1 -C 10 alkyl; and wherein the organoaluminum halide compound is one or more compounds selected from a group consisting of dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, diisobutylaluminum chloride, dioctylaluminum chloride, methylaluminum dichloride, ethylaluminum dichloride, propylaluminum dichloride, isobutylaluminum dichloride, octylaluminum dichloride, methylaluminum sesquichloride, ethylaluminum sesquichloride and butylaluminum sesquichloride compound.