Blends of poly(butylene terephthalate) pbt gf 20 and high density polyethylene at a ratio of
80:20 wt% were reinforced with short glass fibers varying from 10 to 30 wt% to enhance
mechanical properties. Considerable fiber damage occurred during injection molding,
reducing the number average fiber length from the starting value of 4.5 mm to < 1mm. This value decreased with increasing fiber content, which is also responsible
for lowering the reinforcement efficiency. The variation in mechanical properties
has been explained on the basis of fiber concertration.The ability of an engineering plastic material to maintain properties at increased temperature is critical in many applications.