SULFONIC ACID GROUP-CONTAINING POLYMER, METHOD FOR PRODUCING SAME, RESIN COMPOSITION CONTAINING SUCH SULFONIC ACID GROUP-CONTAINING POLYMER, POLYMER ELECTROLYTE MEMBRANE, POLYMER ELECTROLYTE MEMBRANE/ELECTRODE ASSEMBLY, AND FUEL CELL

摘要

Disclosed are a sulfonic acid group-containing polymer having excellent ion conductivity and durability, a method for producing such a sulfonic acid group-containing polymer, a resin composition containing such a sulfonic acid group-containing polymer, a polymer electrolyte membrane, a polymer electrolyte membrane/electrode assembly, and a fuel cell. A first embodiment of the sulfonic acid group-containing polymer contains a constitutional unit represented by the chemical formula (1) below in a molecular chain. [Chemical formula 1] (1) (In the chemical formula (1), X represents a hydrogen or a monovalent cation species; Y represents a sulfonic group or a ketone group; and n represents an arbitrary integer not less than 2.)