Patent ID: 6939581
Filing Date: 2005-09-06
Classification: B01D,C08J,H01M,Y02E,Y02P

Abstract:
1. An impregnation process of a porous support, formed by a polymer compound inert under use conditions, carried out by using colloidal dispersions in water of thermoplastic (per)fluorinated ionomeric polymers containing functional groups convertible into —SO 3 H, said aqueous dispersions of thermoplastic (per)fluorinated ionomeric polymers obtained by polymerization in emulsion of the following monomers: said process comprising the following steps: 1) preparation of an aqueous colloidal dispersion of thermoplastic (per)fluorinated polymers by polymerization in emulsion of at least the following monomers: 2) a) concentration or dilution of the dispersion obtained in 1) having a solid content in the latex greater than 20% by weight; and 3) impregnation of the porous support with the latex obtained in 2b); 4) thermal treatment at a temperature of 20° C. higher than the glass transition temperature of the thermoplastic ionomeric polymers and lower or equal to 200° C.; 5) a) ionomer crosslinking when the equivalent weight is lower than 650 g/eg, and 6) optionally, membrane treatment by immersion at room temperature in an acid aqueous solution of an inorganic strong acid, and subsequent washings by immersion in deonized water up to an about neutral pH of the washing waters.