초록 |
Perfluorinated sulfonic acid membranes have been widely used for polymer electrolyte membrane fuel cell applications because of their high proton conductivity and chemical stability. However, extremely high cost and low service temperature of PFSA membranes raise the need to develop inexpensive and thermally stable hydrocarbon-based membranes. Until now, various sulfonated aromatic multi-block copolymers with enhanced nanophase-separated morphologies have been widely studied. In this study, three different types of sulfonated multiblock copolymers containing phenylene sulfone moieties were synthesized. The variation in local concentration of sulfonic acid in their hydrophilic blocks as well as flexibility of hydrophobic blocks affects humidity dependence of proton transport and other physical properties such as water absorption behaviour, morphologies, and fuel cell performance. |