Liquid crystal polymer composition containing bisphenol A in combination with 4,4'-thiodiphenol

The invention relates to thermotropic liquid crystalline polymer compositions of the general formula: -(CO-C6H4O)m-(CO-C6H4-CO)n -(O-C6H4-X)p-(O-C6H4-C(CH3)2-C6H4-O)q-(O-C6H4-S-C6H4-O)t- where substantially all aromatic substituents are para to one another, where -X- can be either -O- or -NH-, and m, n, p, q and t are mole fractions totaling 1.0, where m is 0 to 0.75, m plus 2p is 0.5 to 0.75, n is 0.125 to 0.5, p is 0 to 0.375, q is 0.125 to 0.25, n equals p plus q plus t, and t is greater than 0.0125, but equal to no greater than 90% of q plus t. Preferably X is -O-, m is from 0.5 to 0.75 and p is less than 0.05. Alternatively, m is less than 0.1 and p is from 0.25 to 0.375. The thermotropic liquid crystalline polymer composition is the reaction product of the copolymerization of: a) p-Hydroxybenzoic acid, b) a member selected from the group consisting of hydroquinone and p-aminophenol, c) Bisphenol A, d) 4,4'-thiodiphenol, and e) terephthalic acid, wherein the thiodiphenol is present in an amount at least equal to 1.25 mole % of the total composition, the Bisphenol A is present in an amount at least equal to 12.5 mole %, and the concentration of the thiodiphenol plus Bisphenol A is up to about 25 mole %.