摘要 |
Hydrophobic diaphragm material, such as crystalline, highly expanded microporous polytetrafluoroethylene film, may be prepared for installation in a chlor-alkali cell by a process involving the steps of (1) immersing the diaphragm in a solution of acetal-type nonionic surfactant in a suitable non-aqueous solvent, (2) rinsing the diaphragm in deionized water, (3) immersing the diaphragm in an aqueous solution containing an amount of acetal-type nonionic surfactant effective to promote wetting for a suitable period of time, and (4) immersing the diaphragm in a brine solution containing about 100 to 200 grams per liter of sodium chloride and an amount effective to promote wetting of an acetal-type nonionic surfactant for a suitable period of time, such as several hours. In some instances, it is also advantageous to subject the diaphragm while immersed in the solvent solution to the action of a vacuum, to release trapped air.
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