FIVE-COMPONENT COPOLYESTER, PROCESS FOR PREPARATION THEREOF, AND SHAPED ARTICLES THEREOF

摘要

A five-component copolyester not described in the prior art literature which comprises at least five components, i.e. (a) two aromatic dicarboxylic acid components composed of a major amount of an isophthalic acid component and a minor amount of another dicarboxylic acid component, (b) a diol component composed of an ethylene glycol component and optionally another diol component, (c) an aromatic monohydroxy-monocarboxylic acid component and (d) a polyfunctional compound component having at least three functional groups. The copolyester has excellent melt moldability, mechanical strength, transparency and gas-barrier property in a well balanced combination, and shows improved properties over conventional copolyesters containing a major amount of isophthalic acid as a dicarboxylic acid component.