FOAM COMPOSITION OF FLUOROCARBON COPOLYMER

PURPOSE:To foam having good properties inherent in fluorocarbon copolymers and uniform and fine structure, obtained by adding submicroscopic Aerosil rendered oleophilic by chemically coating the surface with alkyl groups, to a fluorocarbon copolymer and expanding the mixture. CONSTITUTION:The purpose foam is obtained by adding at least 0.05pt.wt. submicroscopic Aerosil rendered oleophilic by introducing alkyl groups into the surface by use of dimethyldichlorosilane, diethyldichlorosilane or the like, and produced by a vapor-phase process to 100pwt.wt. fluorocarbon copolymer such as ethylene/tetrafluoroethylene or tetrafluoroethylene/hexafluoropropylene. Thus, it becomes possible to obtain a uniform and fine foam, because the submicroscopic Aerosil whose compartibility with a fluorocarbon copolymer is improved by the introduction of alkyl groups is uniformly dispersed in the copolymer.