Polybutylene terephthalate (PBT) is a semi-crystalline polyester-based thermoplastic. It has very good mechanical and electrical properties and very low moisture absorption, which makes it very suitable for use in electronic products.
In addition, PBT has very good thermostability, which means that it can endure high temperatures. Through the addition of fiberglass to the material, even higher strength and thermostability are achieved. It is also very common to add flame retardant to PBT for electrical applications.
PBT has several application areas. As was mentioned above, the plastic is very useful in electronics applications such as lighting (downlights/spotlights), plugs, and switches. It is also very common for PBT to be used in vehicle components such as cowlings and parts for ignition and electrical systems.
● Excellent mechanical properties
● Good thermostability (up to 150°C)
● Low moisture absorption
● Excellent dimensional stability
● Low friction coefficient and good abrasion resistance
● Resistance to chemicals, including aliphatic compounds, oils, and fats
● Good dielectric properties
● Excellent UV resistance
● Melting temperature of roughly 217°C
● Glass-transition temperature (Tg) of 60°C
Some less optimal properties:
● Not resistant to alkalis and strong acids