| 摘要 |
PROBLEM TO BE SOLVED: To provide a solid polymer electrolyte membrane for a direct methanol type fuel cell, high in ion conductivity and low in methanol permeability.SOLUTION: A solid polymer electrolyte for a direct methanol type fuel cell includes a block copolymer comprising a hydrophilic segment and a hydrophobic segment which contain an ion exchange group. The hydrophobic segment includes a structural unit represented by general formula (1), a number average molecular weight Mn of the hydrophobic segment is 2.0×10-1.0×10in terms of GPC, and a ratio between a number average molecular weight Mn of the hydrophilic segment and the number average molecular weight of the hydrophobic segment is 2.0-5.0. |
