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Microporous membrane composites that are non-dewetting are disclosed. These microporous membrane composites are wet with solutions of methanol and water and are non-dewetting following autoclave treatment in water. The microporous membrane composites comprise a microporous membrane support that is c

Microporous membrane composites that are non-dewetting are disclosed. These microporous membrane composites are wet with solutions of methanol and water and are non-dewetting following autoclave treatment in water. The microporous membrane composites comprise a microporous membrane support that is coated with a crosslinked ionomer comprising hydrophilic groups. Compared to the microporous membrane support, the microporous membrane composite has a flow loss on average in isopropyl alcohol of less than 82%.

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1. A fluorocarbon liquid composition comprising a fluorocarbon liquid medium containing a fluorinated ionomer dissolved or dispersed therein, the fluorinated ionomer having iodine and/or bromine atoms at a terminal position, at least 90% by weight of the fluorinated ionomer consisting in particles o

1. A fluorocarbon liquid composition comprising a fluorocarbon liquid medium containing a fluorinated ionomer dissolved or dispersed therein, the fluorinated ionomer having iodine and/or bromine atoms at a terminal position, at least 90% by weight of the fluorinated ionomer consisting in particles of size lower than 200 nm, wherein the fluorinated ionomer comprises units from copolymerization of: i) tetrafluoroethylene;ii) fluorinated monomer units containing ethylenic groups and functional groups chosen from —SO2F, —COOR, —COF or combinations of these, wherein R is a C1 to C20 alkyl radical or a C6 to C20 aryl radical;iii) monomeric units deriving from a bis-olefin, chosen from formulae (OF-1), (OF-2), or (OF-3) where: wherein j is an integer between 2 and 10, and R1, R2, R3, R4, individually equal or different from each other, are H, F or C1 to C5 alkyl or (per)fluoroalkyl group; wherein each of A, equal or different from each other and at each occurrence, is independently F, Cl, or H; each of B, equal or different from each other and at each occurrence, is independently F, Cl, H or ORB, wherein RB is a branched or straight chain alkyl radical which can be partially, substantially or completely fluorinated or chlorinated; E is a divalent group having 2 to 10 carbon atom, optionally fluorinated, which may be inserted with ether linkages; wherein E, A and B have the same meaning as above defined; R5, R6, R7, independently equal or different from each other, are H, F or C1-5 alkyl or (per)fluoroalkyl group; andiv) a compound having the formula Rf(I)x(Br)y, wherein where Rf is a fluoroalkyl or (per)fluoroalkyl or a (per)fluorochloroalkyl group having from 1 to 8 carbon atoms, and wherein x and y are integers from 0 to 2, with 1≦x+y≦2;wherein the fluorocarbon liquid medium comprises a mixture of perfluoropolyethers, said perfluoropolyethers having the general formula F3C—O—[CF2—CF(CF3)—O]n—[CF2—O]m—CF3 wherein m and n are integers, being n>0 and m≧0, said perfluoropolyethers having molecular weight between 300 atomic mass units (amu) and 600 amu, said mixtures having prevailing average boiling points between 55° C. and 135° C. and an average ratio between the indexes m and n (m/n) below 0.05;wherein the fluorinated ionomer has an equivalent weight of between 380 g/eq and 620 g/eq; andwherein the concentration of fluorinated ionomer in the fluorocarbon liquid composition range from 0.1 weight percent to 4 weight percent. 2. The liquid composition of claim 1, wherein the content of the iodine and/or bromine atoms is between 0.1% and 5% by weight based on the ionomer. 3. The liquid composition of claim 1 wherein the liquid composition contains mixtures of perfluoropolyethers having the general formula F3C—O—[CF2—CF(CF3)—O]n—[CF2—O]m—CF3, each perfluoropolyether having molecular weight between 400 and 600 amu, said mixture having a prevailing (“average”) boiling point comprised between 80° C. and 100° C. and an average ratio between the indexes m and n (m/n) below 0.05. 4. The liquid composition according to claim 1 wherein the fluorocarbon liquid medium further comprises a hydrogenated fluoropolyether or a mixture of hydrogenated fluoropolyethers (HFPE) having the general formula R*—O—Rf′—R*′ wherein: —R* and R*′, equal or different from each other, are independently chosen between —CmF2m+1 and —Cn—F2n+1−hHh groups, with m, n being integers from 1 to 3, h being integer ≧1, chosen so that h≦2n+1, with the proviso that at least one of R* and R*′ is a —Cn—F2n+1−hHh group, as defined above;Rf′ is chosen from structures (1), (2), or (3) where:structure (1) is —(CF2O)a—(CF2CF2O)b—(CF2—(CF2)z′—CF2O)c, with a, b and c being integers up to 50, and z′ being an integer equal to 1 or 2, a≧0, b≧0, c≧0 and a+b>0;structure (2) is —(C3F6O)c′—(C2F4O)b—(CFXO)t—, with X being, at each occurrence, independently —F or —CF3; b, c′ and t being integers up to 10, c′>0, b≧0, t≧0; andstructure (3) is —(C3F6O)c′—(CFXO)t—, with X being, at each occurrence, independently —F or —CF3; c′ and t being integers up to 10, c′>0, t≧0. 5. The liquid composition of claim 4 where Rf′ is selected from structures (1) or (2). 6. The liquid composition of claim 1, wherein the fluorocarbon liquid medium comprises the methoxy nonafluorobutane isomers (CF3)2CFCF2—O—CH3 and/or CF3CF2CF2CF2—O—CH3. 7. The liquid composition of claim 1, wherein the monomeric units deriving from a bis-olefin have the formula: R1R2C═CH—(CF2)m—CH═CR5R6 wherein: m=2-10, R1, R2, R5, R6, are equal to or different from each other and are H or C1-C5 alkyl groups. 8. The liquid composition of claim 7, wherein the fluorinated monomeric units containing ethylenic groups and functional groups have the formula: CF2═CF—O—CF2CF2SO2F. 9. The liquid composition of claim 1, wherein the liquid composition additionally comprises a crosslinking agent and a radical initiator. 10. The liquid composition of claim 9, wherein the bis-olefin has the formula: R1R2C═CH—(CF2)m—CH═CR5R6 wherein: m=2-10, R1, R2, R5, R6, are equal to or different from each other and are H or C1-C5 alkyl groups. 11. The liquid composition of claim 9, wherein the radical initiator is an organic dialkyl peroxide. 12. The liquid composition of claim 9 wherein the radical initiator is 2,5-di(t-butylperoxy)-2,5-dimethylhexane. 13. The liquid composition of claim 1, wherein at least 95% by weight of the fluorinated ionomer consists in particles of size lower than 200 nm. 14. The liquid composition of claim 1, wherein at least 99% by weight of the fluorinated ionomer consists in particles of size lower than 200 nm. 15. The liquid composition of claim 14, wherein at least 99% by weight of the fluorinated ionomer consists in particles of size lower than 125 nm. 16. The liquid composition of claim 14, wherein at least 99% by weight of the fluorinated ionomer consists in particles of size lower than 40 nm. 17. The liquid composition of claim 14, wherein at least 99% by weight of the fluorinated ionomer consists in particles of size lower than 15 nm.