| 摘要 |
1,139,413. Polyester/polycarbonate block copolymers. I.C.I. FIBRES Ltd. 11 Jan., 1966 [3 Feb., 1965], No. 4637/65. Heading C3R. Elastomeric block copolymers are made by (a) reacting an hydroxy-terminated aliphatic or cycloaliphatio polyester of molecular weight less than 10,000 with phosgene to form the bischloroformate of the polyester, (b) reacting this bis-chloroformate with a dihydric phenol to produce a polymer with terminal phenolic hydroxyl groups and (c) reacting this polymer with phosgene and a dihydric phenol. Excess dihydric phenol may be used in step (b) to provide the dihydric phenol necessary for step (c). Reactions (b) and (c) may be performed by the conventional interfacial technique in the presence of aqueous alkali and an organic solvent. Preferably the block copolymer contains 55- 70% by weight of polyester blocks. Specified polyesters are those derived from adipic acid, sebacic acid, glutaric acid or dilinoleic acid and ethylene glycol, propylene glycol, mixtures of ethylene glycol with propylene glycol, trimethylene glycol, 1: 3-butanediol, 2: 3-butanediol, 1: 4-butanediol, neopentylene glycol or 1: 3 - dihydroxy - 2: 2: 4- trimethylpropane, and a mixture of propylene glycol and neopentylene glycol. The dihydric phenol may be a substituted or unsubstituted dihydroxy benzene or dihydroxydiphenyl or di-(monohydroxyaryl) alkanes. |
