| 초록 |
In spite of good mechanical properties and thermal stability, sulfonated polyimides show a slow decrease in performance depending on polyimide ring structure during applications, which could be attributed to a loss of ionic conductivity related to either a continuous dehydration or polymer degradation. One of main reasons to account for degradation of sulfonated polymers is the hydrolysis leading to polymer chain scission and decrement of molecular weight. The goal of our research was to investigate the hydrolytic stability of imide cycle and additional ester bond cleavage connected with SO3H presence under water medium, and the relationship between temperature and durability of sulfonated polyimides in hydrated state. In order to confirm and observe as clear information as possible about breakages of bonds, phthalic and naphthalenic sulfonated imide model compounds with ester bonds were synthesized, and aged in water medium under the different thermal condition. The hydrolytic stability of prepared sulfonated imides was observed and evaluated by lyophilization technique to terminate supplementary aging and structural analyses such as FT-IR and 1H / 13C NMR. |
