TABLE OF CONTENTS Polybutylene terephthalate (PBT) resin is a semicrystalline thermoplastics polyester derived from 1,4-butanediol with either terephthalic acid or dimethyl terephthalate (see Fig. 7.1). The commercial production of PBT compound for engineering plastic applications was started in the United States by Celanese in 1970 and grew rapidly as it found utility in various applications, most commonly in the automotive, electrical, and electronics industries. As engineering thermoplastic polyesters, polyethylene terephthalate (PET) compounds are also produced. Because of rapid crystallization and easy processing, PBT compounds are more popular engineering thermoplastics than other polyesters. The main difference between PBT and other commercial polyesters is its fast crystallization characteristics. This ability to crystallize very fast allows fast cycle times during injection molding, and complete crystallization during molding leads to high productivity [1].
PBT is noted for its high heat resistance, stiffness and hardness, excellent electrical properties, and good resistance to environmental influences. PBT resins are high-performance engineering thermoplastics that can be used in a variety of applications, most commonly in functional components and structural parts that are formed by injection molding. In addition to unfilled neat PBT grades, impact-modified, glass-reinforced, mineral-filled, flame-retardant grades and blends based on PBT are commercially available. PBT can be tailored to various applications by blending it with other components (PBT/PC, PBT/PET, PBT/ABS).
Table 7.1 shows a list of suppliers of PBT compounds with their trade names. The thermoplastic...
