Four fluorine funnels -

Teflon (i.e. PTFE, F4) characteristic 　　Outward appearance pure Baise 　　Thermostable: Application temperature - 200~+250℃; bears the low temperature: - 196℃ may maintain 5%; ；
　　
　Anti-corrosive: Bears the strong acid, the strong alkali, the aqua regia and each organic solvent;
　Bears the insulation: The dielectric properties with the temperature, the frequency have nothing to do with; 　High lubrication: In solid state material friction coefficient most bottom; 　　Nonstick: Nonstick any material; 　　Not poisons: Has the physiological inertia, may implant in the human body.