Plastic raw materials are solid or elastomer at room temperature. The raw materials are heated during processing to make them become liquid or molten liquid. Plastics can be divided into "thermoplastics" and "thermosetting plastics" according to their processing characteristics. "Thermoplastics" can be heated and shaped many times and can be recycled. Their fluidity is like mucus, with a slow melting state. Common thermoplastics include PE, PP, PVC, ABS, etc. Thermosetting plastics cure when heated and cooled. Molecular chains form chemical bonds and become a stable structure, so even if heated again, they cannot reach the molten liquid state. Epoxy and rubber are examples of thermosetting plastics. Common plastic processing process types and details: plastic casting (drop molding, condensation molding, rotary molding), blow molding, plastic extrusion, plastic thermoforming (compression molding, vacuum molding), plastic injection molding, plastic welding (friction welding, laser welding), plastic foaming.