Abstract: An object of the present invention is to obtain a novel polymeric material capable of forming a solid polymer electrolyte excellent not only in processability, solvent resistance and durability/stability but also in ion conductivity by introducing sulfonic acid group or phosphonic acid group into a polybenzazole compound having excellent properties in view of heat resistance, solvent resistance, mechanical characteristics and the like. Means attaining the object of the present invention is a polybenzazole compound including an aromatic dicarboxylic acid bond unit having sulfonic acid group and/or phosphonic acid group and satisfying either a condition that inherent viscosity measured in concentrated sulfuric acid is in the range of 0.25 to 10 dl/g or a condition that inherent viscosity measured in a methanesulfonic acid solution is in the range of 0.1 to 50 dl/g.

Abstract: A composite ion exchange membrane having a high swelling resistance and being superior in mechanical strength and ion conductivity can be provided by means of an composite ion exchange membrane including an ion exchange resin composition and a support membrane having a continuous pore penetrating the support membrane, wherein the support membrane is one which accepts the ion exchange resin composition within the pore, and wherein the ion exchange resin composition is one which contains an ion exchange resin containing, as a main component, an aromatic polyether and/or its derivative, the aromatic polyether being obtained by mixing a compound having a specific structure, an aromatic dihalogenated compound and a bisphenol compound with a carbonate and/or a bicarbonate of an alkali metal and polymerizing the mixture in an organic solvent.

Abstract: A polyarylene ether-based compound according to the present invention includes polymer components represented in general formula (1) and general formula (2): wherein Ar indicates a divalent aromatic group, Y indicates a sulfone group or a ketone group, X indicates H or a monovalent cation species, and Ar? indicates a divalent aromatic group.

Abstract: The present invention provides a composite ion exchange membrane which has high mechanical strength and is suitable for use as a solid polymer electrolyte membrane excellent in ionic conductivity and a method for its production. The invention is achieved by a composite ion exchange membrane including a composite layer comprising a support membrane with continuous voids formed of polybenzazole polymer, the support membrane being impregnated with ion exchange resin, and surface layers formed of ion exchange resin free of support membranes, the surface layers being formed on both surfaces of the composite layer so as to sandwich the composite layer therebetween.

Abstract: An object of the present invention is to obtain a novel polymeric material capable of forming a solid polymer electrolyte excellent not only in processability, solvent resistance and durability/stability but also in ion conductivity by introducing sulfonic acid group or phosphonic acid group into a polybenzazole compound having excellent properties in view of heat resistance, solvent resistance, mechanical characteristics and the like.

Abstract: A hindered amine compound having thesolubility in an acidic solution of 5.0×10−3 eq./liter or less comprising at least two specific organic groups in a specific weight ratio in a molecule, or at least two specific monomeric units, which can be used as a stabilizer of a resin.