What is PBT?

PBT plastic refers to a type of plastic composed mainly of polybutylene terephthalate.

Polybutylene terephthalate, also known as tetramethylene terephthalate. Abbreviated as PBT. It is a condensed polymer of terephthalic acid and 1,4-butanediol. PBT and PET are collectively referred to as thermoplastic polyester.

Feature application

Characteristics and applications of polybutylene terephthalate (PBT)

Characteristic

a. Mechanical properties: high strength, fatigue resistance, dimensional stability, and small creep (with very little variation even under high-temperature conditions);

b. Heat aging resistance: The enhanced UL temperature index reaches 120-140 ℃ (outdoor long-term aging resistance is also good);

c. Solvent resistance: no stress cracking;

d. Water stability: PBT is not easily decomposed when exposed to water;

e. Electrical performance:

1. Insulation performance:  (able to maintain stable electrical performance even in damp and high temperatures, making it an ideal material for manufacturing electronic and electrical components);

2. Dielectric coefficient: 3.0-3.2;

3. Arc resistance: 120s

f. Forming processability: injection molding or extrusion molding with ordinary equipment. Due to its fast crystallization rate, good fluidity, and lower mold temperature requirements compared to other engineering plastics. When processing thin-walled parts, it only takes a few seconds, and for large components, it only takes 40-60 seconds.

2. The application of PBT (usually referring to modified varieties);

a. Electronic appliances: connectors, switch parts, household appliances, accessory parts, small electric covers or (heat resistance, flame retardancy, electrical insulation, forming and processing properties);

b. Automobile:

1. External components: mainly including corner grille, engine heat release hole cover, etc;

2. Internal components: mainly including endoscopic braces, wiper brackets, and control system valves;

3. Automotive electrical components: automotive ignition coil twisted tubes and various electrical connectors, etc.

(The number of PBTs used in automobiles is not as high as nylon, polycarbonate, and polyoxymethylene, but with the emergence of low warpage PBTs, they will inevitably be more widely used in automotive components in the future.)

c. Mechanical equipment: Belt drive shaft, electronic computer cover, mercury lampshade, iron cover, baking machine parts for video tape recorder, as well as a large number of gears, cams, buttons, electronic watch casing, camera parts (with heat resistance and flame retardant requirements)