F46/F4/PFA/PTFE四氟管特氟龙，四氟板，四氟垫圈，各种彩色毛细管PTFE is either synthesized by the emulsion polymerization of tetrafluoroethylene monomer under pressure, using free-radical catalysts or it may be produced by the direct substitution of hydrogen atoms on polyethylene with fluorine, using polyethylene and fluorine gas at 20 °C