A multipurpose material that can be adapted to a wide variety of functions
DURANEX® PBT is characterized by its heat resistance and outstanding electrical properties. Its excellent compatibility with various kinds of reinforcement and additive agents means that it can be given many different properties according to specific customer needs. This also allows us to develop a diverse range of grades in our product lineup. This versatile product is utilized in a wide range of areas from wire harness connectors in automobiles to all kinds of electronic components, and also in more familiar everyday items, such as make-up brushes and paper laminate food packaging.
- High dimensional accuracy
- Electrical property
- Acid resistance
- High tracking resistance
- Heat-shock resistance
- Glow wire property
- Long-term durability
- Low water absorbability
- Flame resistance
- Superior formability
PBT is a linear thermoplastic saturated polyester containing ester bonds in its main chain. PBT stands for polybutylene terephthalate. It is a polymer belonging to the same family as PET resin.
PBT possesses a high melting point and high degree of crystallinity, while a low water absorption rate and thermal expansion coefficient give the resin superior dimensional stability. Electrical properties are also superior, and only small changes in electrical properties are exhibited as a result of moisture absorption. Dielectric breakdown voltage is also high.
Both crystalline and non-crystalline structures coexist in PBT. As a result, additives can be readily employed to improve properties and produce various functionalities. Its varied grades include flame resistant grades, fast molding cycle grades, and high impact strength grades. PBT is adopted in a wide variety of familiar products used in everyday life such as electrical components (connectors, micro-switches and condenser cases), office equipment like keyboards, telephones, automotive parts such as in-car electronics and electric vehicle charger guns, medical devices, construction materials, and precision equipment.
※ DURANEX® PBT is manufactured and sold by WinTech Polymer Ltd., an associated company.
Raw ingredients and production method
As PBT is an ester polymer, it is polymerized from esters, themselves synthesized from acids and alcohols. With terephthalic acid used as the acid ingredient and 1, 4-butanediol as the alcohol ingredient, PBT polymer is made via polycondensation. This method is known as the esterification method.
Terephthalic acid is a solid that possesses sublimability and, because purification is difficult, a method also exists whereby terephthalic acid is esterified using methanol, with resulting dimethyl terephthalate and 1, 4-butanediol polycondensated to form the PBT polymer. This method is “ester interchange.” Regardless of which method is employed to manufacture the PBT polymer, the same properties and performance are exhibited if the molecular weight is the same.
While unreinforced PBT is used widely, in general, the addition of reinforcing material improves mechanical and thermal properties. By incorporating various reinforcing materials, many grades of the PBT polymer with various characteristics are made.
List of leading grades
|HB, standard||GF15% reinforced||3105|
|HB, standard||GF30% reinforced||3300|
|Low warpage, LD series||GF30% reinforced, hydrolysis resistance||733LD|
|Hydrolysis resistant||GF30% reinforced||330HR|
|Hydrolysis resistant,heat shock resistant||GF30% reinforced||531HS|
|Alkali resistance improved||GF30% reinforced, hydrolysis resistance||532AR|
|Super high flow, HB||GF30% reinforced||SF3300|
|Super high flow, HB||GF30% reinforced, low warpage||SF733LD|
|Flame retardant, excellent glow-wire property||GF reinforced||330GW*|
|Higher impact resistant||Unfilled, flame retardant, higher comparative tracking index||457EV|
|Halogen-free, higher comparative tracking index||GF30% reinforced||330NF|
|Better surface appearance, higher gloss, flame retardant||GF reinforced,low warpage||756HA|
|Flame retardant,standard,UL approved regrind 50% inclusive||GF15% reinforced||GFR315|
|Flame retardant,standard,UL approved regrind 50% inclusive||GF30% reinforced||GFR330|
Electronic throttle body (ECU case)
IH cooking heater
Paper laminate (for food)
Power supply gun