Patent ID: 6268419
Filing Date: 2001-07-31
Classification: C08G,C08K,Y10T

Abstract:
A method of producing a thermotropic liquid crystalline copolyester composition comprising the steps of:a) producing a thermotropic liquid crystalline copolyester by a method in which the amount of out-gasses emitted therefrom is very small comprising the steps of:(1) charging in a reactor 5-100 mol % of aromatic hydroxycarboxylic acid, 0-47.5 mol % of aromatic dicarboxylic acid and 0-47.5 mol % of aromatic diol, so that the sum of mol % of each material is 100 mol % and the mol % of aromatic dicarboxylic acid and that of aromatic diol are substantially equal;(2) adding acetic anhydride of an amount which satisfies the formula below,1.08.gtoreq.(B-C)/A.gtoreq.1.04""A"" represents the total molar number of the hydroxy group in a reaction system, ""B"" represents the molar number of the acetic anhydride to be added, and ""C"" represents the molar number of water present in the reaction system prior to addition of acetic anhydride;(3) acetylation;(4) melt polymerization;(5) solid-phase polymerization to produce a thermotropic liquid crystalline copolyester; and(b) blending with said thermotropic liquid crystalline copolyester based on 100 parts by weight of the thermotropic liquid crystal copolyester from 0.001 to 1 part by weight of at least one phosphite ester having the general formula I: ##STR3##wherein R and R' each represent a group selected from the group consisting of alkyl group, alkenyl group, aryl group and aralkyl group, and R and R' may represent the same group.