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The tetrafluoroethylene material can be used for a long time at -180～260oC. This material is resistant to acid, alkali and various organic solvents, and it is almost insoluble in all solvents. At the same time, polytetrafluoroethylene has the characteristics of high temperature resistance, its friction coefficient is extremely low, and it does not stick to the reaction medium. Therefore, it is widely used in reaction materials that cannot be tolerated by metal materials.