Plastics can be divided into two types: thermosetting and thermoplastic. The former cannot be reshaped and used, and the latter can be repeatedly produced. Plastics mainly have the following characteristics:

①Most plastics are light, chemically stable, and will not rust; ②Good impact resistance; ③Good transparency and wear resistance; ④Good insulation, low thermal conductivity; ⑤General formability , Good colorability, low processing cost; ⑥Most plastics have poor heat resistance, high thermal expansion rate, and easy to burn; ⑦Poor dimensional stability, easy to deform; ⑧Most plastics have poor low temperature resistance and become brittle at low temperatures; ⑨Easy to age; ⑩Some Some plastics are easily soluble in solvents.

High-end nylon modification has the advantages

1. High mechanical strength, good toughness, high tensile and compressive strength. The specific tensile strength is higher than that of metal, and the specific compressive strength is comparable to that of metal, but its rigidity is not as good as that of metal. The tensile strength is close to the yield strength, which is more than twice as high. The ability to absorb shock, stress and vibration is strong, and the impact strength is much higher than that of general plastics, and is better than acetal resin.

2. Outstanding fatigue resistance, the parts can maintain the original mechanical strength after repeated bending. Common escalator handrails and new bicycle plastic rims are often used in occasions where the periodic fatigue effect is extremely obvious.

3. High softening point, heat resistance (such as nylon 46, etc., high crystalline nylon has a high heat distortion temperature, and can be used for a long time at 150 degrees. After PA66 is reinforced by glass fiber, its heat distortion temperature can reach 250 degrees or more ).

4. Smooth surface, low friction coefficient and wear resistance. It is self-lubricating when used as a movable mechanical component, and has low noise. It can be used without lubricant when the friction effect is not too high; if it is really necessary to use a lubricant to reduce friction or help disperse.