| 摘要 |
PURPOSE:To obtain a polyether markedly small in double refraction, excellent in light transmission, low in water absorptivity and markedly low in warp upon absorption of moisture, having specified repeating units and a specified mol.wt. CONSTITUTION:A polyether resin mainly consisting of repeating units of formula I and/or formula II and having a mol.wt. of 5,000-200,000. In formulas I and II, R1 is a group selected from among groups of formulas III-VI, -O- and -S-, R3 and R4 are each a 12C or lower alkyl, cycloalkyl or H, R5 is a 12C or lower alkylene or an alkylidene, R2 is a 12C or lower alkyl, cycloalkyl, alkylcarbonyl or H, X1-X4 are each H, F, Cl, Br or a 4C or lower alkyl, R6 and R7 are each a 12C or lower alkylene or alkylidene, R8 and R9 are each a 4C or lower alkyl, cycloalkyl or H, and R10 is a 12C alkyl, cycloalkyl, alkylcarbonyl or H. |
