According to its own performance, plastic can be divided into two kinds of thermoplastic plastic and thermosetting plastic, which can basically maintain its characteristics, and can only be fused into one time. According to its use, it can be divided into universal, cheap and comprehensive properties, such as PE, P P, PVC, PS, and amido plastics have good physical and mechanical strength, which may replace the engineering plastics used on engineering machinery such as ABS, nylon, polyester, POM, TPX-1, etc., and a kind of engineering plastics with excellent performance in a certain performance, such as: Special Not good radiation resistance, high temperature resistance and other special plastics, such as: polyaryl sulfone, liquid crystal polymer, etc. Thermoplastic plastics can be divided into amorphous polymers and crystallized polymers according to the molecular crystallization size of thermoplastic resins.