PBT Plastic | Long Glass Fiber Reinforced PBT (PBT-LGF)

What is PBT?

Polybutylene terephthalate (PBT) is a semi-crystalline engineering thermoplastic polyester. It is produced via polycondensation of 1,4-butylene glycol and terephthalic acid (PTA) or dimethyl terephthalate (DMT), forming a milky white translucent to opaque resin. PBT exhibits excellent mechanical strength, chemical resistance, thermal stability, and electrical insulation properties, making it ideal for demanding engineering applications.

Basic Properties of PBT

• Specific gravity: 1.31 g/cm³
• Melting point: 225~275°C
• Glass transition temperature (Tg): 22–43°C
• Rockwell hardness (R scale): 118
• Water absorption: 0.34%
• Molding shrinkage: 1.7~2.3%

PBT-LGF | Long Glass Fiber Reinforced PBT

PBT-LGF combines PBT with long glass fibers, improving mechanical strength, fatigue resistance, dimensional stability, and creep resistance. These properties are maintained even under high-temperature conditions.

Advantages of PBT-LGF

• Excellent mechanical strength and fatigue resistance
• High heat resistance: UL temperature index 120–140°C
• Good solvent resistance and no stress cracking
• Easy flame-retardant processing: UL94 V-0 achievable
• Excellent electrical insulation: high resistivity, dielectric strength, arc resistance
• Good molding and secondary processing: injection molding and extrusion
• Fast crystallization and good fluidity: thin walls can be processed in seconds

PBT-LGF Technical Data Sheet (TDS)

Applications of PBT-LGF

Long glass fiber reinforced PBT is widely used in electronics, automotive, and industrial applications due to its high mechanical strength, heat resistance, electrical insulation, and dimensional stability.

• Electronics: fuse-less wire breakers, electromagnetic switches, transformers, appliance handles, connectors, housings
• Automotive: door handles, bumpers, distributor covers, fenders, wire guard shells, wheel covers
• Industrial parts: OA fans, keyboards, fishing reels, lampshades, and other mechanical components

Processing of PBT-LGF

PBT-LGF can be easily processed via injection molding or extrusion using standard equipment. Due to fast crystallization and good fluidity, mold temperatures are lower than other engineering plastics, enabling rapid processing of both thin-walled and large parts.

PBT-LGF Product Details

Lab & Factory

Frequently Asked Questions

Q: Does long glass fiber injection require special molding machines or molds?

A: Yes. Injection molding machines, screws, nozzles, and mold structures must meet long fiber reinforcement requirements.

Q: How to prevent rough surfaces or floating fibers in PBT-LGF injection molding?

A: Ensure plastic particles are fully dried and plasticized, adjust mold temperature appropriately, and polish mold surfaces for smooth finishes.