刘伯温致力打造火热全网_性感美女毛片_日韩在线小视频_中文字幕久久欲求不满

The five engineering plastics commonly used in China are polycarbonate, POM, polyamide, thermoplastic polyester and modified polyphenylene oxide

　　1> Polyamide:

(PA, commonly known as nylon) has won our attention because of its low specific gravity, high tensile strength, wear resistance, good self smoothness, excellent impact resistance, and the functions of both hardness and softness. In addition, it has simple processing, high power, light specific gravity (only 1/7 of metal), and can be processed into various products to replace metal. It is widely used in cars and transportation industry. Typical products include pump impeller, electric fan blade, valve seat, bushing, bearing, various external plates, car electrical appearance, cold and hot air control valve and other parts. About 3.6~4 kg of nylon products are consumed for each car. Polyamide has the largest share in the car industry, followed by electronics and electrical.

　　2> Polycarbonate:

(PC) not only has the strength similar to that of non-ferrous metals, but also has ductility and strong endurance. Its impact strength is very high. It can not be damaged by hammering, and can fully appreciate the explosion of TV screen. Polycarbonate has excellent clarity, and can be applied with any coloring. Because of the above excellent functions of polycarbonate, it has been widely used in various safety lampshades, signal lights, bright protective plates of gymnasiums and stadiums, lighting glass, high-rise building glass, car mirrors, windshield plates, aircraft cabin glass, and motorcycle driving helmets. The most used shopping malls are computers, office equipment, cars, substitute glass and sheets, and CD and DVD discs are one of the most potential shopping malls.

　　3> Polyoxymethylene:

Polyoxymethylene (POM) is a kind of engineering plastics with excellent functions. It is known as "seizing steel" and "super steel" in foreign countries. POM has the hardness, strength and rigidity of similar metals. It has excellent self smoothness, excellent fatigue resistance and elasticity in a wide range of temperature and humidity schemes. In addition, it has good chemical resistance. POM is replacing some malls traditionally occupied by metals, such as making many parts instead of zinc, brass, aluminum and steel, at a lower cost than many other engineering plastics. Since its inception, POM has been widely used in electronic and electrical, machinery, appearance, daily light industry, cars, building materials, agriculture and other fields. POM also shows a good increasing trend in many new fields, such as medical skills, sports equipment and so on.

　　4> Polybutylene terephthalate:

(PBT) is a thermoplastic polyester. Compared with other thermoplastic engineering plastics, the non reinforced PBT has better processing and electrical functions. The glass transition temperature of PBT is low. When the mold temperature is 50 ℃, it can be crystallized flexibly, and the processing cycle is short. Polybutylene terephthalate (PBT) is widely used in electronics, electrical and car industries. Because of its high insulation and temperature resistance, PBT can be used as flyback transformer of TV, distributor and incineration coil of car, shell and base of office equipment, various external parts of car, electromechanical fan of air conditioner, base of electronic stove and shell of office equipment.

　　5> Polyphenylene oxide:

The chemical formula is abbreviated as PPO. It is a thermoplastic resin prepared by oxidative coupling polymerization of 2,6-disubstituted phenol, which is generally in the form of earthy yellow powder. Polyphenylene oxide (PPO) composed of 2,6-dimethylphenol is commonly used. It has excellent inductive function. Its biggest feature is that it has excellent standard stability and excellent electrical insulation under long-term load. It has a wide range of temperature schemes and can be used for a long time in the scheme of - 127 ~ 121 ℃. With excellent water and steam resistance, the product has high tensile strength, impact strength and creep resistance. In addition, it has good wear resistance and electrical function. It is mainly used to replace stainless steel to make surgical and medical instruments. In the electromechanical industry, it can be used to make gears, blower blades, pipes, valves, screws and other fasteners and connectors. It can also be used to make components in the electronic and electrical industries, such as coil frames and printed circuit boards.

This article is from Jiangmen Engineering Plastics:http://www.latexbbs.com/