Patent ID: 7449532

Claim:
A cycloolefin copolymer obtained by ring opening polymerization, comprising a structural unit represented by general formula (1) and exhibiting a single peak in a derivative differential scanning calorimetry curve obtained by differential scanning calorimeter (DSC), having a temperature width of the rising part in the peak of 35° C. or below, and having a glass transition temperature (Tg) of 110° C. or above, wherein the cycloolefin copolymer comprises a copolymer of 8-methyl-8-methoxycarbonyltetracyclo[4.4.0.1 2,5 .1 7,10 ]-3-dodecene with tricyclo[4.3.0.1 2,5 ]deca-3,7-diene: wherein m is 0 (zero), 1 or 2, p is 0 (zero) or 1, X independently represents a group represented by formula: —CH═CH— or a group represented by formula: —CH 2 CH 2 —, R 1 to R 4 each independently represent a hydrogen atom; a halogen atom; a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms and optionally having a linking group containing oxygen, nitrogen, sulfur, or silicon; or a polar group, and R 1 and R 2 , or R 3 and R 4 together may combine to form a mono- or polycyclic carbocyclic or heterocyclic ring.