| 摘要 |
PURPOSE:To obtain easily a bipolar membrane having high bonding strength and stable electrochemical performances by casting a monomer solution over the surface of an ion exchange membrane, pressing a cation exchange membrane against the cast solution, polymerizing the cast solution under pressure, and introducing ion exchange groups into the polymer. CONSTITUTION:This bipolar membrane is obtained by casting a monomer solution over the surface of a first ion exchange membrane, pressing a second ion exchange membrane with a charge opposite in sign to that of the first ion exchange membrane against the cast monomer solution, polymerizing the solution, and introducing ion exchange groups into the obtained polymer. Because of high current efficiency and excellent acid resistance, a cation exchange membrane made of a perfluorocarbon polymer comprising repeating units of the formula (wherein (m) is 0 or 1; (n) is 1-5; x/y is 2-16; X is SO3M or COOM; and M is H, an alkali metal, an alkaline earth metal or ammonium) is desirable as the cation exchange membrane. |
