| 摘要 |
PURPOSE:To obtain the titled resin providing optical molded articles having extremely low double reflux, excellent light transmission, extremely low water absorption ratio, excessively low warpage by water absorption, improved mechanical characteristics and heat resistance, having a specific repeating unit and specific number-average molecular weight. CONSTITUTION:A polyvinyl ether resin having preferably >=70wt.% repeating unit shown by formula I (R is norbornyl group which may contain >=2C substituent group), preferably a repeating unit shown by formula II and >=5,000, preferably 10,000-1,000,000 number-average mol.wt. The resin has 90-200 deg.C glass transition point, has improved heat resistance, <=0.2% low water absorption ratio, >=85% light transmission in optical characteristics and <=30X10<-13>cm<2>/dyne absolute value of coefficient of photoelasticity and is useful as an optical molding material. |
