Polypropylene, abbreviated as PP, is a colorless, odorless, non-toxic, translucent solid substance. Polypropylene is a kind of thermoplastic synthetic resin with excellent performance, which is a colorless and translucent thermoplastic lightweight general-purpose plastic. Polypropylene has chemical resistance, heat resistance, electrical insulation, high strength mechanical properties and good wear-resistant processing performance, which makes it widely developed and applied in many fields such as machinery, automobile, electronic and electrical appliances, construction, textile, packaging, agriculture, forestry, fishery and food industry since its birth. In recent years, with the rapid development of China's packaging, electronics, automotive and other industries, it has greatly promoted the development of China's industry. And because of its plasticity, polypropylene materials are gradually replacing wood products, and the mechanical functions of metals have been gradually replaced by high strength, toughness and high wear resistance. In addition, polypropylene has good graft and composite functions, and has a huge application space in concrete, textile, packaging, agriculture, forestry and fishery.