| 摘要 |
PURPOSE:To obtain the title material having enhanced high-temp. chemical resistance and improved service life as well as improved sealing properties against gas, by impregnating the pores of a porous fluoroplastic with fluoroelastomer so as to have a volume ratio of them in a particular range. CONSTITUTION:A sealing material obtd. by impregnating the pores of a porous fluoroplastic with fluoroelastomer so as to have a volume ratio of the porous fluoroplastic to the fluoroelastomer of 1-5:9-5. A preferable fluoroplastic is polytetrafluoroethylene. Examples of the fluoroelastomer include binary or higher copolymers of tetrafluoroethylene, hexafluoropropylene and vinyl fluoride. The sealing material is obtd. by a method (1) comprising preparing a porous fluoroplastic and impregnating the fluoroplastic with a fluoroelastomer or a method (2) comprising extrusion-molding a mixture of a fluoroplastic with a fluoroelastomer and stretching the extrudate. The sealing material prepared by the method (2) is particularly excellent. |
