Polypropylene is a polymer formed by the addition of propylene. It is white waxy material with transparent and light appearance. The density is 0.89-0.91g/cm3, inflammable, melting point is 165 ℃, soften at about 155 ℃, and use temperature range is - 30-140 ℃. Under 80 ℃, it can resist the corrosion of acid, alkali, salt solution and various organic solvents, and decompose under high temperature and oxidation. Polypropylene is widely used in the production of fiber products such as clothing, blankets, medical devices, automobiles, bicycles, parts, transportation pipelines, chemical containers, etc., as well as food and drug packaging.