| 摘要 |
<p>A process for making oriented film of perfluorinated polymer which is either an ion exchange polymer or a melt-fabricable precursor thereto, which has been extended in the range of about 1.3X to 3X in at least one planar direction, is disclosed. Such film is made by swelling a film in melt-fabricable form in a liquid organic compound and either restraining it while drying, or stretching it followed by drying under restraint. The oriented melt-fabricable film can be converted to ion-exchange film by hydrolysis under restraint. The resulting film has good anion rejection properties, strength and flatness, and remains taut in use after being mounted dry in a chloralkali cell.</p> |
