Polytetrafluoroethylene molded articles coated with fused fluoropolymer resin

摘要

The present invention relates to a molded article of polytetrafluoroethylene or modified polytetrafluoroethylene having a fluoropolymer resin coating, the coating comprising a heat-flowable tetrafluoroethylene copolymer wherein the surface of the coated article has a reduced roughness compared to the molded article prior to coating. The coating for the molded article is preferably a fused powder, most preferably formed by electrostatically applying a fluoropolymer powder resin to the molded PTFE article. In a preferred embodiment, the fluoropolymer powder resin comprises a mixture of heat-flowable tetrafluoroethylene copolymer powder and a polytetrafluoroethylene that has a temperature of crystallization of at least 305 DEG C and a heat of crystallization of at least 50J/g. The surfaces of the articles are smoother than the original articles so that they resist adhesion of chemical contaminants and have applicability for chemical containers and transport pipes in the rigorously clean environment of the semiconductor industry.