DEMISTER Material Polytetrafluoroethylene has a very high chemical resistance, such as in concentrated sulfuric acid, nitric acid, hydrochloric acid, even boiling in aqua regia, its weight and performance have no change, and it is almost insoluble in most solvents, only slightly soluble in paraffins (about 0.1g / 100g) above 300 ℃. Polytetrafluoroethylene is non hygroscopic, non combustible, extremely stable to oxygen and ultraviolet, so it has excellent weather resistance. It should be noted that polytetrafluoroethylene can not withstand strong reduction atmosphere melting of alkali metals, ammonia alkali solution (alkali metals dissolved in liquid ammonia), some fluorides (such as TFA), naphthalene sodium salt, etc. can rapidly corrode polytetrafluoroethylene products. The dielectric constant and loss of polytetrafluoroethylene in a wide frequency range are very low, and the breakdown voltage, volume resistivity and arc resistance are high.

The radiation resistance of polytetrafluoroethylene is poor. It is degraded by high energy radiation, and the electrical and mechanical properties of the polymer are obviously reduced. Polytetrafluoroethylene is produced by free radical polymerization of tetrafluoroethylene. Industrial polymerization is carried out by stirring in the presence of a large amount of water to disperse the reaction heat and facilitate temperature control. The polymerization is generally carried out at 40-80 ℃, 3-26 kgf / cm. Inorganic persulfate and organic peroxides can be used as initiators, and redox system can also be used as initiators. The exothermic energy per mole of tetrafluoroethylene is 171.38kj. Dispersion polymerization requires the addition of perfluorinated surfactants, such as perfluorooctanoic acid or its salts.