화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.37, No.17, 12586-12596, 2012
Cross-linked proton exchange membranes for direct methanol fuel cells: Effects of the cross-linker structure on the performances
A highly sulfonated poly (ether ether ketone) with pendant amino groups (Am-SPEEK) has been synthesized. The resulting copolymer showed good solubility in common organic solvents. Then the pendant amino groups of the Am-SPEEK were utilized to react with two kinds of cross-linker, epoxy resin and dibromide, to yield various cross-linked membranes. After cross-linking, the membranes could not dissolve in common solvents, just became swollen. In generally, all the cross-linked membranes showed improved mechanical properties and high dimensional stabilities, whereas the uncross-linked membranes highly swollen or even dissolved in water at high temperature. The proton conductivity of the membranes increased with an increase in temperature. At 80 degrees C, all the cross-linked membranes showed high proton conductivity, in the range of 0.111-0.140 S cm(-1). Especially, the TMBP cross-linked membrane showed a proton conductivity of 0.140 S cm(-1), which was higher than that of Nafion 117 (0.125 S cm(-1)). The membranes with high proton conductivity, good oxidative stability, and improved methanol residence have been successfully developed. Furthermore, the influence of different main chain of the crosslinker on the performance of the cross-linked membranes was also investigated. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.