PVC can be divided into soft PVC and hard PVC. Among them, hard PVC accounts for about 2/3 of the market, and soft PVC accounts for 1/3. Soft PVC is generally used for the surface layer of floors, ceilings and leather, but because soft PVC contains plasticizers (this is also the difference between soft PVC and hard PVC), the physical properties are poor (for example, the upper water pipe needs to withstand a certain water pressure, soft PVC is not suitable for use), so its scope of use is limited. Hard PVC does not contain plasticizers, so it is easy to form and has good physical properties, so it has great development and application value. In the production process of polyvinyl chloride materials, several additives are bound to be added, such as stabilizers, plasticizers, etc. If all environmental protection additives are used, then PVC pipes are also non-toxic, tasteless and environmentally friendly products.