A thermoplastic resin composition comprising:
(a) Alkylene aryl polyester copolymers having metal sulfonate units represented by the formula IA:
or the formula IB:
where p=1-3, d=1-3, p+d=2-6, n=1-5, and A is an aryl group containing one or more aromatic rings where the sulfonate substituent is directly attached to an aryl ring, R″ is a divalent alkyl group and the metal sulfonate group is bound to the polyester through ester linkages;
(b) glass fibers.