Polybutylene terephthalate (PBT) is a milky white, semi-transparent to opaque, crystalline thermoplastic polyester.PBT boasts high heat resistance, toughness, fatigue resistance, self-lubrication, low friction coefficient, weather resistance, and low water absorption rate of just 0.1%. It maintains various physical properties and electrical insulation in humid environments, but has high volume resistance and dielectric loss. It is resistant to hot water, alkalis, acids, oils, but is susceptible to halogenated hydrocarbons and has poor hydrolysis resistance. It can crystallize rapidly at low temperatures and has good molding properties. Its drawbacks include low notch impact strength and high shrinkage rate during molding. Therefore, most applications use glass fiber reinforcement or inorganic filling modification, which can double the tensile and bending strengths and significantly increase the heat deflection temperature.Used for electrical appliances, automotive, aircraft manufacturing, communication, and home appliances. For example, modified with glass fiber, PBT can be used to produce electronic components that require high dimensional stability under long-term high-temperature conditions.