PURPOSE: Title composition that is composed of a linear aromatic polyester, fiberglass, a non-fibrous filler and a rubbery polymer and outstanding for mechanical, thermal, electrical and chemical properties and gives molded products with reduced difference in directional properties.

CONSTITUTION: (A) 85W40 wt% of a linear aromatic polyester as polyethylene terephthalate or polybutylene terephthalate, (B) 5W60 wt% of fiberglass, (C) 5W50 wt% of a non-fibrous filler as talc or titanium dioxide and (D) 1W20 wt% of a rubbery polymer with a glass transition point of lower than 0°C measured by means of device for differential thermal analysis at a temperature rising speed of 8°C/min such as acrylic rubber, ethylene-vinyl acetate copolymer are mixed under melting in an extruder and then pelletized.

EFFECT: The resulting composition is outstanding for mechanical, thermal and chemical properties and gives molded products with reduced warpage and high dimensional stability under elevated temperatures.