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An impregnation process of a porous support including immersing the support in an aqueous colloidal dispersion of ionomeric (per)fluorinated polymer, containing suiphonyl fluoride groups and having a concentration greater than 15% by weight, thermal treatment at 200° C. or less, conversion of the io

An impregnation process of a porous support including immersing the support in an aqueous colloidal dispersion of ionomeric (per)fluorinated polymer, containing suiphonyl fluoride groups and having a concentration greater than 15% by weight, thermal treatment at 200° C. or less, conversion of the ionomer sulphonyl groups into the corresponding salts, ionomer crosslinking when ionomer equivalent weight is less than 650 g/eq.

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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 ?SO3H,said aqueous dispersions of thermoplas

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 ?SO3H,said aqueous dispersions of thermoplastic (per)fluorinated ionomeric polymers obtained by polymerization in emulsion of the following monomers: (A) one or more (per)fluorinated monomers, containing at least one ethylene unsaturation, (B) one or more (per)fluorinated comonomers containing functional groups convertible into the above acid groups, and (C) 0.01 to 5% by moles of a bis-olefin of formula (R1R2)C?CH?(CF2)m?CH?C(R5R6), ??(I) wherein; m is an integer from 2 to 10; R1, R2, R5, and R6 are equal to or different from each other, and are H or C1-C5 alkyl groups, 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: (A) one or more (per)fluorinated monomers, containing at least one ethylene unsaturation; (B) one or more (per)fluorinated comonomers containing functional groups convertible into the above acid groups; and (C) 0.01 to 5% by moles of a bis-olefin of formula; (R1R2)C?CH?(CF2)mCH?C(R5R6) (I) 2) a) concentration or dilution of the dispersion obtained in 1) having a solid content in the latex greater than 20% by weight; and b) optional addition of surfactants to obtain a dispersion surface tension lower than 40 mN/m; 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 b) conversion of the functional groups of the thermoplastic ionomeric polymers into the corresponding salts, by contacting the membrane with a basic aqueous solution, at temperatures comprised between 60° C. and the boiling temperature of the aqueous solution, and subsequent washings by immersion of the membrane in deionized water at room termperature, until obtaining an almost neutral pH of the washing waters; 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. 2. The process according to claim 1, wherein the crosslinking of step 5a) is optional when the polymer has equivalent weight higher than 650 g/eq.3. The process according to claim 1, wherein steps 3) and 4) are repeated until obtaining a completely occluded membrane with Gurley number>10,000 (ASTM D726-58).4. The process according to claim 1, wherein the porous support is a membrane having (a) a porous structure containing knots linked each other by fibrils, and/or (b) a porous structure formed by only interconnected fibrils, or (c) a tissue.5. The process according to claim 1, wherein the thermoplastic (per)fluorinated polymers have equivalent weight from 380 to 1,800.6. The process according to claim 1, wherein in thermoplastic polymers the (per)fluorinated monomers of type (A) are selected from the following:vinylidene fluoride (VDF); C2-C8 perfluoroolefins; C2-C8 chioro- and/or bromo- and/or iodo-fluoroolefins, such as chlorotrifluorethylene (CTFE) and bromotrifluorethylene; perflucroalkylvinylethers (PAVE) CF2?CFORf, wherein Rf is a C1-C6 perfluoroalkyl; perflucro-oxyalkylvinylethers CF2?CFOX, wherein X is a C1-C12 perfluoro-oxyalkyl having one or more ether groups the fluorinated monomers of type (B) are selected from one or more of the following:F2C?CF?O?CF2?CF2?SO2F; F2C?CF?O?[CF2?CXF?O]n?CF2?CF2?SO2F; wherein X=Cl, F or CF3; n=integer from 1 to 10;F2C?CF?O?CF2?CF2?CF2?SO2F; F2C?CF?Ar?SO2F wherein Ar is an aryl ring. 7. The process according to claim 6, wherein the fluorinated ionomers comprise:monomeric units deriving from TFE; monomeric units deriving from CF2?CF?O?CF2CF2SO2F; monomeric units deriving from the bis-olefin of formula (I); optionally, iodine atoms in terminal position. 8. The process according to claim 1, wherein the crosslinking of step 5a) can take place by both ionic and radical route.9. An impregnation process of a porous surpport, formed by a polymer compound inert under use conditions, carried out by using colloidal dispersions in water of thermoolastic (per)fluorinated polymers containing functional groups convertible into ?SO3H,said agueous dispersions of thermoplastic (per)fluorinated polymers obtained by polymerization in emulsion of the following monomers: (A) one or more (per)fluorinated monomers, containing at least one ethylene unsaturation, and (B) one or more (per)fluorinated comonomers containing functional groups convertible into the above acid groups, said process comprising the following steps: 1) preparation of an aaueous colloidal dispersion of thermoplastic (per)fluorinated polymers by polymerization in emulsion of at least the following monomers: (A) one or more (per)fluorinated monomers, containing at least one ethylene unsaturation; and (B) one or more (per)fluorinated comonomers containing functional groups convertible into the above acid groups; and 2) a) concentration or dilution of the dispersion obtained in 1) having a solid content in the latex areater than 20% by weight; and b) optional addition of surfactants to obtain a dispersion surface tension lower than 40 mN/m; 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 b) conversion of the functional groups of the ionomer into the corresponding salts, by contacting the membrane with a basic aqueous solution, at temperatures comprised between 60° C. and the boiling temperature of the aqueous solution, and subsequent washings by immersion of the membrane in deionized water at room termperature, until obtaining an almost neutral pH of the washing waters; 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, wherein the crosslinking of step 5a) takes place by both ionic and radical route and wherein the crosslinking of radical type uses ionomers containing units of the bis-olefin of formula (I) and iodine in the terminal position of the macromolecule chains.10. 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 polymers containing functional groups convertible into ?SO3H,said aqueous disoersions of thermoolastic (per)fluorinated polymers obtained by polymerization in emulsion of the following monomers:(A) one or more (per)fluorinated monomers, containing at least one ethylene unsaturation, and (B) one or more (per)fluorinated comonomers containing functional groups convertible into the above acid groups, 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: (A) one or more (per)fluorinated monomers, containing at least one ethylene unsaturation; and (B) one or more (per)fluorinated comonomers containing functional groups convertible into the above acid groups; and 2) a) concentration or dilution of the disoersion obtained in 1) having a solid content in the latex greater than 20% by weight; and b) optional addition of surfactants to obtain a dispersion surface tension lower than 40 mN/m; 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 polymer and lower or equal to 200° C.; 5) a) ionomer crosslinking when the equivalent weight is lower than 650 g/eg, and b) conversion of the functional groups of the ionomer into the corresponding salts, by contacting the membrane with a basic aqueous solution, at temperatures comprised between 60° C. and the boiling temperature of the agueous solution, and subsequent washings by immersion of the membrane in deionized water at room termperature, until obtaining an almost neutral pH of the washing waters; 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, wherein the crosslinking of step 5a) takes place by both ionic and radical route and wherein the crosslinking composition contains:(a) a crosslinking co-agent, in an amount in the range 0.5-10% with respect to the polymer; (b) a metal compound, in amounts in the range 1-15% by weight with respect to the polymer, selected from oxides or hydroxides of divalent metals, optionally combined with a weak acid salt; (c) other conventional additives; and (d) inorganic or polymer reinforcing fillers, optionally fibril fillers. 11. The process according to claim 1, wherein the latexes contain particles having a diameter from 5 to 400 nm.12. The process according to claim 1, wherein in step 1) in the colloidal aqueous dispersion of the ionomeric thermoplastic polymers fluorinated surfactants are present, of formula:Rf?X?M+wherein Rf is a C5-C16 perfluoroalkyl chain or a perfluoropolyoxyalkylene chain, X? is ?COO? or ?SO3?, M+ is selected from: H+, NH4+, an alkaline metal ion.13. The process according to claim 1, wherein the surfactants used in step 2b) are non-ionic, ionic or amphoteric surfactants or mixtures thereof, wherein the hydrophobic portion of the surfactant molecule can be of hydrocarbon, fluorocarbon, fluoropolyether or silicone type.14. The process according to claim 13, wherein the surfactant is the octylphenoxypolyethoxyethanol compound with a number of ethoxylic units comprised between 9 and 10, in an amount from 1% to 20% with respect to the latex.15. The process according to claim 1, wherein after step 6 a further heating step is effected at temperatures from 150° C. to 210° C.