国产精品自产拍在线观看首页_国产美女遭强高潮开双腿_亚洲日本文字天天更新_国产美女高潮久久久久白浆,国产精品亚洲一区二区三区天天看|久久久综合九色综合|欧美日韩精品视频一区二区在线播放|亚洲小视频在线观看

Performance analysis of engineering plastics PBT

Polybutylene terephthalate (PBT)

Polybutylene terephthalate (PBT) is a crystalline thermoplastic engineering plastic formed by the polymerization of dimethyl terephthalate (DMT) and 1,4-butanediol. Because the - CH2 - chain of PBT resin grows, the molecular chain is easy to bend. Therefore, the glass transfer temperature is lower than that of pet, and the crystallization speed is faster. Its chemical structure formula is as follows

PBT was successfully researched by Celanese company of the United States in the early 1970s, and was listed under the trade name Celanese. Subsequently, international well-known manufacturers BASF, Bayer, GE and Ticona of the United States, Toray and Mitsubishi Chemical of Japan, Shin Kong synthetic fiber of Taiwan, Changchun artificial resin, Nanya plastics and other companies successively put into production teams, with a total of more than 30 global manufacturers.

PBT can also be called thermoplastic polyester plastic. In order to be applicable to different processing industries, generally, it will be added with additives or mixed with other plastics. With different proportions of additives, products of different standards can be made. Because PBT has heat resistance, weather resistance, drug resistance, good electrical properties, low water absorption and excellent gloss, it is widely used in electronic appliances, car parts, machinery, household products, etc. PBT products, together with PPE, PC, POM, PA, etc., are called the five general-purpose engineering plastics.

The associated industries used in the downstream of PBT include cars, electronics / electrical appliances and machinery:

Adaptor

The adapter is a bridge between signals and an indispensable component for the transmission of electronic signals and power connection. The balanced physical properties and price of PBT are in line with the needs of the adapter. PBT is usually added with 30% glass fiber as the adapter. PBT is widely used because of its mechanical properties, solvent resistance, good formability and low price. PBT can not be used in SMT adapter due to poor heat resistance of welding plutonium.

Radiator fan

The second major use of PBT is to use it in the heat dissipation fan. The heat dissipation fan is placed in the machine for long-term rotation to help heat dissipation. The physical properties of plastic are required to have heat resistance, flame resistance, insulation and mechanical strength. PBT is usually used as the outer frame and blade of the heat dissipation fan in the form of 30% fiber addition

Bobbin

The third use of PBT is as the winding shaft in transformers and relays, which is generally formed by 30% injection of PBT plus fiber. The physical properties required for the winding shaft include insulation, heat resistance, welding resistance, fluidity, strength, etc. the applicable data include phenolic resin, PBT, PA6, pet.

Phenolic resin has good properties, but its formability is not as good as PBT. Therefore, PBT resin is used for products with small scale and disordered shape. Although PBT welding plutonium has poor heat resistance, it has a trend to increase the use of recyclable PBT in Europe, America, Japan and other countries with high awareness of environmental protection.

Car industry

About 2200 metric tons of PBT are consumed in the car industry, half of which form pbt/pc alloy with PC and can be used as car bumper. In addition, PBT can also be used for window motor housing, locomotive motor parts, car driver gear box, etc.

Others

Other uses of PBT, such as adding 15% glass fiber as the inner base and shell of the bulb base, using pbt/pc composite as the sole of skates, and others such as relay shell, socket, switch and tuner shell.

Article source: PBT engineering plastics http://www.lyx0.com/