| 摘要 |
PURPOSE:To provide a copolymerized polyester containing specific copolymer components, having extremely stable crystallinity and melting point, and capable of forming fibers and films, etc. having excellent heat resistance and flame retardance by melt spinning or melt film-forming. CONSTITUTION:A melt-moldable polyester having an intrinsic viscosity of 0.3- 1.4 and composed mainly of the structural units of formula I and formula II (n is 2, 4 or 6). The unit of formula I can be produced by the polycondensation of alpha,beta- bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid and/or its ester-forming derivative with an alkylene glycol, and the unit of formula II can be produced by the polycondensation of alpha,beta-bis(2-bromophenoxy)ethane-4,4'-dicarboxylic acid and/or its ester-forming derivative with an alkylene glycol. The content of the unit of formula II in the copolymer is preferably 1-99mol%, especially 10-90mol%.
|
