An Overview to Poly(Butylene Terephthalate)
2026-05-14
What Is Poly(Butylene Terephthalate)?
Polybutylene terephthalate (PBT) is a semi-transparent or opaque, crystalline thermoplastic polyester resin, also known as poly(tetramethylene terephthalate). It has a molecular weight of 30,000 to 40,000, a milky white or pale yellow appearance, a glossy surface, and a density of 1.31 to 1.55 g/cm³.
How Is Polybutylene Terephthalate Made?
The production processes for polybutylene terephthalate resin are primarily divided into the ester exchange method (DMT method) and the direct esterification method (PTA method), with the DMT method further categorized into batch DMT and continuous DMT processes. It is characterized by high-temperature resistance, moisture resistance, oil resistance, excellent electrical insulation properties, chemical resistance, rapid molding, ease of molding, and low moisture absorption.
It is produced industrially in a two-step batch or continuous process. The first step involves the transesterification of dimethyl terephthalate (DMT) with 1,4-butanediol (BDO) to produce hydrobutyl terephthalate (bis-HBT) at a temperature of 200°C. The second step consists to the polycondensation of bis-HBT at 250°C to yield PBT.
Polybutylene Terephthalate Properties
Name | Poly(Butylene Terephthalate) |
Abbreviation | PBT |
CAS | 26062-94-2 |
Appearance | Milky white, semi-transparent to opaque, semi-crystalline solid |
Melting Point | 233 °C |
Decomposition Temperature | Above 300 °C |
Density | 1.31 to 1.55 g/cm³ |
Water Absorption Rate | 0.2–0.5% |
Glass Transition Temperature | 20~60 °C |
Special Properties | High heat resistance, toughness, fatigue resistance |
Applications | Automotive, connectors, electrical appliances, etc. |
Storage Temp. | -70°C |
Safety | PBT is non-toxic, has good biocompatibility, and does not cause significant skin irritation. |
Polybutylene Terephthalate Uses
Automotive | Exterior automotive parts: engine heat vent covers, corner grilles, etc. Interior automotive parts: wiper brackets, rearview mirror supports, and control system valves Automotive electrical parts: ignition coil bobbins and various electrical connectors | Stability, wear resistance, flame retardancy, aging resistance, etc. |
Mechanical Equipment | Parts for baking machines, mercury lamp housings, computer casings, electric iron covers, as well as numerous buttons, cams, watch cases, gears, camera parts, etc. | Heat resistance, flame retardancy |
Energy-Saving Lamps | Plastic energy-saving lamp heads | Heat resistance, long-term aging resistance, flame retardancy to UL94 V-0 level |
Connectors | Connectors for computers, other digital products, telecommunications, and home appliances, such as motherboard slots, telephone or network cable plugs, etc. | Electrical insulation, heat resistance, flame retardancy, high strength, fatigue resistance |
FAQS
| Is PBT Plastic Toxic? | PBT is non-toxic, has good biocompatibility, and does not cause significant skin irritation. |
| What is polybutylene terephthalate used for? | Automotive, connectors, electrical appliances, etc. |
| Is PBT FDA-approved? | Yes, Polybutylene Terephthalate (PBT) is generally considered food-safe and is approved for specific applications by the FDA. |
| What is PBT made out of? | Polybutylene Terephthalate (PBT) is a high-performance engineering plastic made by the polymerization of 1,4-butanediol (BDO) and terephthalic acid (PTA) or dimethyl terephthalate (DMT). |
| About polybutylene terephthalate price | Contact Kerton Chemicals Right Now!! |
| Polybutylene terephthalate market | Global PBT market size was approximately USD 3.13 billion in 2025, with projections suggesting growth to over USD 4 billion by 2033–2034. |
Previous page:
Blog update
What are the types of chemical materials
2024-11-05
What do chemical materials do?
2024-11-05
What are the industrial chemicals
2024-11-05