| 摘要 |
An impregnation process of a porous support, comprising the following steps: 1) preparation of an aqueous colloidal dispersion of thermoplastic (per)fluorinated polymers; 2) a) concentration or dilution of the dispersion obtained in 1); b) optional surfactant, addition to obtain a dispersion having a surface tension lower than 40 mN/m; 3) porous support impregnation with the latex obtained in 2b); 4) thermal treatment at a temperature of 20° C. higher than the glass transition temperature of the thermoplastic polymer and lower than 200° C.; 5) a) if the ionomer has equivalent weight lower than 650 g/eq, ionomer crosslinking, b) conversion of the functional groups into the corresponding salts; 6) optional treatment of the membrane at room temperature in an acid aqueous solution of a strong inorganic acid and subsequent washings with deionized water.
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