摘要:
The present invention relates to a liquid composition comprising a solvent and a fluorinated ion-exchange polymer, a solid support at least partially impregnated with said composition and an article comprising said support.
摘要:
A method of fabricating an electrolyte membrane includes providing a reinforcement substrate that has impregnated therein a linear perfluorinated electrolyte polymer resin, and cross-linking the electrolyte polymer resin in-situ in the reinforcement substrate to thereby form a reinforced electrolyte membrane with cross-linked perfluorinated electrolyte polymer material impregnated therein.
摘要:
The present invention provides a fluorinated ionomer [polymer (I)] comprising recurring units derived from at least the following monomers: (i) 5 to 50 % by weight of a fluorinated monomer [monomer (A)] containing at least one -SO 2 X functionality, preferably having the formula of CF 2 =CF-O-(CF 2 CF(CF 3 )O) m -(CF 2 ) n SO 2 X (I) wherein m is 0 or 1, n is an integer between 0-10, and X is selected from F, OH, and O - Me + , wherein Me + indicates an alkali metal ion or an ammonium cation of formula NR 4 + where each R independently represents a hydrogen atom or a monovalent organic radical selected from aliphatic radicals having from 1 to 8 carbon atoms and arylic or alicyclic radicals having from 3 to 8 carbon atoms; (ii) a non-functional fluorinated monomer [monomer (B)] having at least one ethylene unsaturation; and (iii) a fluorinated polyfunctional compound having the general formula: (CR 1 R 2 =CFCF 2 -O) a -R f -((O) c -CF=CR 3 R 4 ) b (ll) wherein: a is an integer equal to or larger than 1, preferably a is 1, 2, or 3; b is 0 or 1 and the sum of a and b is an integer equal to or larger than 2; c is 0 or 1; R 1 , R 2 , R 3 and R 4 are independently selected from F, H, alkyl, alkoxy, polyoxy alkyl, perfluoroalkyl, perfluoroalkoxy or perfluoropolyoxy alkyl, preferably F; and R f represents a hydrocarbon or fluorocarbon group having at least two carbon atoms. The low-EW perfluorinated ionomers made of polymer (I) are adapted to be processed into thin films, which are found to have superior physical stability than the existing products and are thus well suited for low humidity or high temperature electrochemical applications. Moreover, these low-EW ionomers are melt processable and have limited loss of volatile substances at their melt processing temperatures.
摘要:
A liquid composition comprising at least one aprotic organic solvent and at least one fluorinated ion exchange polymer which consists of recurring units derived from a chlorofluoroolefin of formula CF2=CCIY, wherein Y is F or CI, and from at least one fluorinated functional monomer selected among those of formula CF2 =CF-O-(CF2CF(CF3)O)m-(CF2)nSO2X, wherein m is an integer equal to 0 or 1, n is an integer from 0 to 10 and X is chosen among halogens (CI, F, Br, I), -O-M+, wherein M+ is a cation selected among H+, NH4 +, K+, Li+, Na+, or mixtures thereof is disclosed. The liquid composition is suitable for the preparation of ion exchange membranes, in particular composite membranes, for use in fuel cell applications.
摘要:
This invention relates to ionomers and to ionically conductive compositions formed therefrom. The ionomers comprise polymerized units of monomers A and monomers B, wherein monomers A are perfluoro dioxole or perfluoro dioxolane monomers, and the monomers B are functionalized perfluoro olefins having fluoroalkyi sulfonyl, fluoroalkyi sulfonate or fluoroalkyi sulfonic acid pendant groups, CF 2 =CF(O)[CF 2 ] n SO 2 X. The ionically conductive compositions of the invention are useful in fuel cells, electrolysis cells, ion exchange membranes, sensors, electrochemical capacitors, and modified electrodes.
摘要:
The invention pertains to a process for stabilizing a semi-crystalline fluoropolymer comprising ion exchange groups, said process comprising: suspending at least one semi-crystalline fluoropolymer having ion exchange groups [polymer (I)] in at least one fluorinated organic dispersing medium [medium (M)] so as to obtain a dispersion (D) of polymer (I) in a dispersing medium (M); contacting said dispersion (D) with fluorine under irradiation with U. V. radiation so as to obtain a stabilized polymer. Still objects of the invention are a stable semi-crystalline fluoropolymer as above defined having a low amount of unstable ends groups of -COF type, the use of the stabilized fluoropolymer obtained by the process or of the stable fluoropolymer in fuel cells devices, a membrane and a membrane-electrode assembly comprising said fluoropolymers.