Generally refers to plastics with large output, wide application, good formability and low price. There are five general varieties of plastics, namely polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS) and acrylonitrile-butadiene-styrene copolymer (ABS). These five categories of plastics occupy the vast majority of plastic raw materials, and the rest can be classified into special plastics such as PPS, PPO, PA, PC, POM, etc., which are used in daily life products. It is used in high-end fields such as engineering, defense and science and technology, such as automotive, aerospace, construction, and communications. Plastics can be classified into thermoplastics and thermosets according to their plasticity classification. In general, thermoplastic products can be recycled, while thermosetting plastics cannot. According to the optical properties of plastics, they can be divided into transparent, translucent and opaque materials such as PS, PMMA, AS, PC, etc. Most other plastics are opaque plastics.