Polybutylene terephthalate (PBT) is a semi-crystalline thermoplastic polyester formed by the condensation polymerization of terephthalic acid and 1,4-butanediol. It can be regarded as the “performance cornerstone of electronic and electrical products” - through the alternating arrangement of rigid benzene rings and flexible butyl segments, it achieves high crystallization rate and excellent processing fluidity, thus possessing outstanding electrical insulation, high heat resistance (with a long-term use temperature of up to 140°C), resistance to chemical solvents (especially oil and weak acids), low moisture absorption and dimensional stability. PBT not only has good rigidity and anti-rheology properties, but also can significantly enhance mechanical strength when combined with glass fibers (with tensile strength exceeding 130 MPa), and is widely used in electronic and electrical products (connectors, relays, coil frames, switches), automotive industry (lamp housings, ignition coils, windshield wiper arms), household appliances (electric iron handles, microwave oven accessories), and industrial fibers (brush wires, sewing threads), etc., in situations that require comprehensive heat resistance, insulation and precise molding.