Annihilation Process of Positron in Degraded Nafion?-117

摘要

Annihilation process oi positron in Nafion-117 was investigated under several kinds or conditions to elucidate degradation process of polymer electrolyte membrane. It was found that ortho-positronium stayed beside cluster wall and side chains and its lifetime reflected cluster size. Annihilation process of positron was found to be greatly influenced by the electronic state of sulfonic group. These results showed that positron annihilation spectroscopy would be good tool to detect degradation of polymer electrolyte membrane.