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Engineering plastics can be used as engineering materials and substitute for metals. Excellent mechanical function, heat resistance and dimensional stability are required. There are polyoxymethylene, polyamide, polycarbonate, ABS plastics and so on. For example, the mechanical and mechanical functions of polyoxymethylene are similar to those of copper and zinc. If it is used as a bearing on a car, its service life is twice as long as that of metal. It can also be used as other spare parts. Polycarbonate can not only replace some metals, but also replace glass, wood and alloy. It can be used as the shell of various instruments, bicycle frame, windshield and furniture of aircraft.

(1) polyamide (nylon)

Polyamide is a kind of thermoplastic engineering plastics. It is a long chain polymer compound formed by many units with amide group structure. For example, nylon-66 is polycondensated from adipic acid and hexanediamine, and its structural formula is

Due to its light weight, excellent mechanical strength, wear resistance and good corrosion resistance, polyamide is widely used to replace copper and other metals in the manufacturing of bearings, gears, pump blades and other parts in machinery, chemical industry, surface, car and other industries. Polyamide has high strength after melt spinning. It can be used as synthetic fiber and medical suture.

(2) ABS engineering plastics

ABS resin is a copolymer of acrylonitrile (a), butadiene (b) and styrene (s)

ABS resin maintains the excellent electrical function and easy processing formability of styrene, but also increases elasticity, strength (the characteristics of butadiene), heat resistance and corrosion resistance (excellent function of acrylonitrile), and has high surface hardness and good chemical resistance. By changing the share of the above three components, various functions of ABS can be changed. Therefore, ABS engineering plastics have a wide range of uses and primary uses In mechanical, electrical, textile, car and shipbuilding industries.

(3) polycarbonate

Polycarbonate is a new type of thermoplastic engineering plastics

Polycarbonate has excellent electrical insulation function and mechanical function, especially in shock resistance function. It has high tolerance, wide temperature planning (- 100 ~ 130 ℃), high transparency (known as "Tongming metal") and convenient processing and molding. It can replace not only some metals, but also glass and wood. In recent years, polycarbonate has developed rapidly and has been widely used in machinery, car, aircraft, instrument surface and electrical appliances.

Source: Jiangmen engineering plastics http://diywl.cn/