| abstract |
PROBLEM TO BE SOLVED: To easily control the upper limit of the amount of sulfonic acid that impairs mechanical properties, and to obtain a sulfonated polymer having high proton conductivity over a wide temperature range, Provided is a polyarylene-based copolymer which has excellent mechanical strength, suppresses swelling in warm water, and provides a proton conductive membrane having excellent durability. SOLUTION: (A) 40 to 3 mol% of an aromatic compound unit having an electron-withdrawing group and an ether bond in a main chain, and (B) an aromatic compound unit having no electron-withdrawing group in a main chain of 60 to 60%. A polyarylene-based copolymer consisting of 97 mol% [(A) + (B) = 100 mol%], and A proton conductive membrane comprising a sulfonated polymer obtained by sulfonating this copolymer. |