摘要 |
A solid polymer electrolyte membrane is provided that is inexpensive, and is excellent in the ionic conductivity characteristics, the methanol crossover characteristics and the mechanical characteristics. The solid polymer electrolyte membrane contains a block copolymer A containing a hydrophilic segment having an ion exchange group and a hydrophobic segment, and a block copolymer B containing a hydrophilic segment having an ion exchange group and a hydrophobic segment and having a smaller ion exchange capacity than the block copolymer A, and has a structure where a region A having the block copolymer A agglomerated therein is dispersed in a matrix constituted by a region B having the block copolymer B agglomerated therein, with a microscopic phase-separated structure having a period of from 10 to 100 nm being formed in the region A and the region B. |