摘要 |
Disclosed is a method of forming an unsintered, nonwoven, wettable, microporous diaphragm of a fluorocarbon polymer. The diaphragm is prepared by maintaining a nonwoven, fibrous mat of a leachable material in contact with the external surfaces of the fluorocarbon polymer film while hot pressing the halocarbon polymer film above its flow temperature and below its thermal decomposition temperature, and thereafter leaching the fibrous mat out of the halocarbon film. Additionally, monomers having acidic or basic groups may be grafted to the pore walls. Also disclosed is a method of rendering a hydrophobic fluorocarbon polymer film wettable by compressing the film between a pair of nonwoven mats of a leachable fibrous material while maintaining the film above the flow temperature thereof but below its decomposition temperature and then leaching the fibrous material out of the film.
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