CYCLOOLEFIN POLYMER COMPOSITION

摘要

Disclosed is a cycloolefin composition comprising: (a) a cycloolefin polymer that is (A-1) a random copolymer of an .alpha.-olefin with a particular cycloolefin, (A-2) a ring-opening polymer of the cycloolefin or (A-3) a hydrogenation product of the ring-opening polymer (A-2), and (b) a cycloolefin polymer that is (B-1) a random copolymer of an .alpha.-olefin with a particular cycloolefin, (B-2) a ring-opening polymer of the cycloolefin or (B-3) a hydrogenation product of the ring-opening polymer (B-2). The cycloolefin polymer (A) has a glass transition temperature (Tg) lower than 15.degree.C and the cycloolefin polymer (B) a Tg of at least 70.degree.C. A difference of refractive indices of the polymers (A) and (B) is no more than 0.015. The particular cycloolefin for the polymer (A) is for example 5-phenylbicyclo¢2.2.1!hept-2-ene or bicyclo¢2.2.1!hept-2-ene. The particular cycloolefin for the polymer (B) is for example tetracyclo ¢4.4.0.1 2,5. 1 7,10!-3-undecene or bicyclo¢2.2.1!hept-2-ene.