摘要 |
To provide an ion exchange membrane capable of stably developing a high current efficiency in electrolysis of an aqueous alkali chloride solution containing organic substances and thereby capable of producing an aqueous alkali hydroxide solution stably with high efficiency. A fluorinated ion exchange membrane containing at least one layer of a fluoropolymer having a pendant side chain structure having a carboxylic acid group bonded to the polymer main chain by means of a connecting chain, wherein the connecting chain up to the carboxylic acid group in the pendant side chain is a continuous chain composed of from 6 to 8 atoms, and the connecting chain has a diether structure with no branched structure. |