| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cycloolefin resin composition which has a small birefringence and a low glass transition temperature by compounding a cycloolefin resin with a specified amount of a compound for reducing glass transition temperature. SOLUTION: A cycloolefin resin selected from among (A) random copolymers of ethylene and a monomer represented by formula I or II, (B) ring-opening (co)polymers of a monomer represented by formula I or II, (C) hydrogenation products of polymer B, and (D) graft modification products of polymers A, B, and C is compounded with 0.1-30 wt.% compound for reducing glass transition temperature, giving a resin composition which has a glass transition temperature at least 5 deg.C lower than that of the cycloolefin resin and gives a molded item having a birefringence equivalent to that of the resin. In the formulas, n, k, p, and q are each 0 or 1; m is an integer; r and s are each 0-2; R1 to R18, Ra, and Rb are each H, halogen, a hydrocarbon group, or the like; and R21 to R39 are each H, halogen, a hydrocarbon group, alkoxy, or the like. The compound for reducing glass transition temperature is an org. compound having a mol.wt. of 100-10,000.
|
