| 摘要 |
A novel block or random copolymer is composed of the reaction prod. of (a) a prepolymer formed from an aliphatic ester (I) selected from glycolide, lactide (l,d,dl or meso), trimethylene carbonate, p-dioxanone, dioxepanone, delta-valerolactone, beta-butyrolactone, epsilon-decalactone, 2,5-diketo-morpholine, pivalactone, alpha,alpha-diethylpropiolactone, ethylene carbonate, ethylene oxalate, 3-methyl-1,4-dioxane-2,5-dione, 3,3-dimethyl- 1,4-dioxane-2,5-dione, 3,3-diethyl-1,4-dioxane- 2,5-dione, pivalactone, gamma-butyrolactone, 1,4-dioxepan-2-one, 1,5-dioxepan-2-one, 1,4-dioxan-2-one and 6,8-dioxabicyclooctane-7-one and (b) the balance of the copolymer comprising an aromatic repeating unit of formula -(CO-Y-X-Y-COO)- (II). Y = pref. a direct link, but may be a divalent -(CH2)n- or -(CH2)n-O- radical and the ether C, if present, is directly linked to X and the -CO-Y- gps. are symmetrically disposed on the divalent aromatic radical X; n = 1-4; X = a gp. of formula (i)-(iii). R = (CH2)n, -O-, -(C(CH3)2)-, -(O-(CH2)m-)p-, etc. R1 = -O- or -(C(CH3)2-)-; n' = 1-4; n'' = 1-20; m = 1-20; p = 0-20. |
