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Engineering plastic is a kind of plastic with the weather resistance, scale and impact resistance of PC and the processing fluidity of ABS resin.

Compared with plastics, engineering plastics can meet higher requirements in terms of mechanical function, durability, corrosion resistance, heat resistance, etc., and are more convenient to process and can replace metal materials. Engineering plastics are widely used in electronic and electrical, automotive, construction, office equipment, machinery, aerospace and other industries. Replacing steel with plastics and wood with plastics has become a popular trend in the world.

Engineering plastics has become a category of growth rate in the world plastics industry. Its development not only plays a supporting role in the national pillar industry and modern high-tech industry, but also promotes the transformation of traditional industries and the adjustment of product structure.

Engineering plastics are increasingly used in automobiles, mainly as bumpers, fuel tanks, instrument panels, body panels, doors, lamp covers, fuel pipes, radiators and engine related parts.

Extended data

The main functional features of engineering plastics are:

(1) Compared with general plastics, it has heat-resistant and cold resistant functions, and has mechanical functions in a wide range of temperatures, which is suitable for use as structural data;

(2) Excellent corrosion resistance, less affected by the environment, and excellent durability;

(3) Compared with metal materials, it has simple processing, high production efficiency, and can simplify procedures and save costs;

(4) Excellent dimensional stability and electrical insulation;

(5) Light weight, high specific strength, excellent friction reduction and wear resistance.

Engineering plastics refer to industrial plastics used as industrial parts or shell materials, which are excellent in strength, impact resistance, heat resistance, hardness and anti-aging resistance. The Japanese industry defines it as "a high-function plastic that can be used as structural and mechanical parts, with heat resistance above 100 ℃, and is mainly used in industry". Its functions include:

1. thermal property: glass handling temperature (TG) and melting point (TM); High thermal deformation temperature (HDT); High temperature for long-term operation (ul-746b); Wide application temperature range; The coefficient of thermal expansion is small.

2. mechanical properties: high strength, high mechanical modulus, low latency, strong wear and fatigue resistance.

3. others: good chemical resistance, electrical resistance, fire resistance, weather resistance and scale stability.

Those regarded as general engineering plastics include polycarbonate (PC), polyamide (nylon), polyacetal (POM), modified polyphenylene oxide (modified PPE), polyester (PETP, pbtp), polyphenylene sulfide (PPS), polyaryl ester, and thermosetting plastics include unsaturated polyester, phenolic plastics, epoxy plastics, etc. Their basic characteristics are that the tensile strength exceeds 50MPa, the tensile strength is 500kg/cm, the impact resistance exceeds 50j/m, the bending elasticity is 24000kg/cm, the load winding temperature exceeds 100 ℃, and the hardness and aging performance are excellent. Polypropylene can also be included in the range of engineering plastics if its hardness and cold resistance are improved. In addition, it also includes fluorine plastics with weak strength and excellent heat resistance and drug resistance, silicon melting compounds with excellent heat resistance, polyamide imide, polyimide, POLYBISMALEIMIDE, Polysufone (PSF), PES, Propylene Plastics, modified melamine plastics, btresin, peek, Pei, liquid crystal plastics, etc.

The chemical structures of engineering plastics are different, so their drug resistance, friction characteristics and motor characteristics are different. Because of the different formability of various engineering plastics, some are suitable for any molding method, and some can only be processed by a certain molding method, which leads to limitations in application. The impact resistance of thermosetting engineering plastics is poor, so most of them increase glass fiber. In addition to the high impact resistance of polycarbonate, engineering plastics generally have the properties of hard, brittle and small elongation. However, if 20-30 glass fibers are added, its impact resistance will be improved.

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It is the plastic used in engineering

Engineering plastic materials and plastics that can replace metal to manufacture parts [1] engineering plastics have good generalization, high rigidity, small creep, high mechanical strength, good heat resistance and good electrical insulation. They can be used in harsh chemical and physical environments for a long time, and can replace metal as engineering structure data, but the price is expensive and the output value is small.

The main functional features of engineering plastics are:

(1) Compared with general plastics, it has heat-resistant and cold resistant functions, and has mechanical functions in a wide range of temperatures, which is suitable for use as structural data;

(2) Excellent corrosion resistance, less affected by the environment, and excellent durability;

(3) Compared with metal materials, it has simple processing, high production efficiency, and can simplify procedures and save costs;

(4) Excellent dimensional stability and electrical insulation;

(5) Light weight, high specific strength, excellent friction reduction and wear resistance.

Engineering plastics mainly include polycarbonate (PC), polyamide (nylon, polyamide, PA), polyacetal (POM), polyphenylene oxide (PPO), polyester (PET, PBT), polyphenylene sulfide (PPS), polyaryl esters, etc.

Source: Jiangmen engineering plastics http://yzw188.cn/