| 摘要 |
PURPOSE:To obtain a copolyester which excells in flame retardancy, heat resistance and melt moldability and easily forms a thermoplastic liquid crystal phase, mainly consisting of three specified structural units. CONSTITUTION:A copolyester of an intrinsic viscosity >=0.5 [in a 50/50(wt). phenol/C2H2Cl4 mixed solvent at 20 deg.C] is obtained by reacting a unit (A) comprising a phosphorus-containing aromatic diol and an aromatic dicarboxylic acid and represented by the structure of formula I (wherein Ar1 is a trivalent aromatic group) with an alkylene terephthalate unit (B) comprising terephthalate acid and an alkylene glycol and represented by the structure of formula II (wherein n<1> is 2-4 and n<2> is 1-2) and a unit (C) of the structure of formula III (wherein Ar2 is a bivalent aromatic group), e.g., 4-hydroxybenzoic acid residue, at a molar ratio of A to B of 90-10/10-90 and a molar ratio of (A+B) to C of 95-5/5-95 so as to arrange units A, B and C at random.
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