Abstract: A superacidic ester group is useful in the production of ionomers for polymer electrolyte fuel cells. A polymer is produced from said vinyl monomer. A process produces a polymer containing a superacidic group. The vinyl monomer contains a haloalkyl ester group of a superacid, wherein the number of carbon atoms of the haloalkyl ester group is no more than 10, and the halogen in the haloalkyl group is chlorine and/or fluorine. A polymer containing said vinyl monomer as a repeating unit can be converted to a polymer containing a superacid group using at least one procedure of 1) heat treating at 50°C. to 350°C., and 2) contacting with a protic compound.

Abstract: A perfluorovinyl ether monomer represented by the following formula (1): wherein: m is an integer of from 0 to 5; n is an integer of from 1 to 5; and each of R1 and R2 independently represents a hydrogen atom, an unsubstituted or substituted C1-C10 hydrocarbon group, or a substituted silyl group, with the proviso that, when each of the R1 and R2 is independently the hydrocarbon group or the substituted silyl group, R1 and R2 are optionally bonded together, thereby forming a ring.

Abstract: There is provided a process for producing a fluorinated vinyl ether from a fluorinated acid fluoride compound having an ester group as a precursor of a carboxylic acid group, or a SO2F group as a precursor of a sulfonic acid group, in high yield by simple operations. Said process is a production process comprising pyrolyzing a carboxylic acid potassium salt with a specific structure represented by the following formula in the absence of a solvent and/or while maintaining the salt in the solid state: wherein X is —CO2R or —SO2F, and R is an alkyl group.

Abstract: The object of the present invention is to provide a vinyl monomer containing a superacidic ester group useful in the production of ionomers for polymer electrolyte fuel cells, and its production process. In addition, another object of the present invention is to provide a polymer produced from said vinyl monomer and its production process, as well as a process for producing a polymer containing a superacidic group from said polymer. The inventive vinyl monomer contains a haloalkyl ester group of a superacid, wherein the number of carbon atoms of the haloalkyl ester group is no more than 10, and the halogen in the haloalkyl group is chlorine and/or fluorine. A polymer containing said vinyl monomer as a repeating unit can be converted to a polymer containing a superacid group using at least one procedure of 1) heat treating at 50° C. to 350° C., and 2) contacting with a protic compound.

Abstract: A membrane electrode assembly for a polymer electrolyte fuel cell characterized by using, as solid polyelecrolyte of at least one of a membrane and a catalyst binder, a fluorinated sulfonic acid polymer with a monomer unit represented by the following general formula (3): (wherein Rf1 is a bivalent perfluoro-hydrocarbon group having a carbon number of from 4 to 10), wherein said fluorinated sulfonic acid polymer has melt flow rate (MFR) not higher than 100 g/10 min at 270° C. when a —SO3H group in said polymer is converted to —SO2F.

Abstract: There is provided a process for producing a fluorinated vinyl ether from a fluorinated acid fluoride compound having an ester group as a precursor of a carboxylic acid group, or a SO2F group as a precursor of a sulfonic acid group, in high yield by simple operations.

Abstract: A perfluorovinyl ether monomer represented by the following formula (1): 1

Abstract: Disclosed is a hybrid electrolyte comprising a shaped porous polymer structure comprising a polymer matrix and a plurality of cells dispersed in the polymer matrix, the polymer matrix containing a crosslinked polymer segment and having a gel content in the range of from 20 to 75%, wherein the shaped porous polymer structure is impregnated and swelled with an electrolytic liquid. A method for producing the hybrid electrolyte and a method for producing an electrochemical device comprising the hybrid electrolyte are also disclosed. The hybrid electrolyte of the present invention has a high ionic conductivity, an excellent stability under high temperature conditions and an excellent adherability to an electrode. Further, by the method of the present invention, the hybrid electrolyte having the above-mentioned excellent properties and an electrochemical device comprising such a hybrid electrolyte can be surely and effectively produced.