Polytetrafluoroethylene [PTFE, F4] is one of the best corrosion resistant materials in the world today, hence the reputation of "King of Plastics". It can be used for a long time in any kind of chemical medium, and its production has solved many problems in China's chemical, petroleum, pharmaceutical and other fields. PTFE seals, gaskets, gaskets. PTFE seals, gaskets and sealing gaskets are molded and processed by suspended polymerized PTFE resin. Compared with other plastics, PTFE has excellent chemical resistance and temperature resistance, and it has been widely used as a sealing and filling material. It has a high degree of chemical stability and excellent chemical corrosion resistance, such as strong acid resistance, strong alkali, strong oxidant, etc., has outstanding heat resistance, cold resistance and wear resistance, long-term use temperature range of -200-+250 °C, and excellent electrical insulation, and is not affected by temperature and frequency. In addition, it has the characteristics of non-sticking, non-absorbent, non-combustible, etc.