本論文利用2,2-bis (4-carboxyphenyl)-hexaflouopropane 和3,3’-diaminobenzidine兩種單體成功地合成出六氟聚苯咪唑高分子(fluorine-containing polybenzimidazole, 6F-PBI)，在成膜過程中添加離子液體1-hexyl-3methylimidazolium trifluoromethanesulfonate (HMI-Tf)與6F-PBI混摻，製備出一系列的聚苯咪唑/離子液體複合薄膜，並進行機械性質和熱性質等測試。研究顯示，HMI-Tf的添加使複合薄膜的熱性質與機械性質下降，卻提升了質子導電度，在160 ℃下均達0.0021 S/cm。
　　薄膜進行磷酸摻雜後，在磷酸摻雜量僅有129 %的複合薄膜於160 ℃下均有0.015 S/cm以上的質子導電度。在單電池測試部分，分為十四天開關測試與三十天穩定測試。在開關測試 (160 ℃下負載電流200 mA/cm2操作12小時而後關閉燃料降回室溫)，複合薄膜維持穩定的開路電壓，顯示能防止燃料的穿越。而在三十天穩定測試 (160 ℃下負載電流200 mA/cm2操作720小時)，複合薄膜輸出電壓衰退速度為0.054 mV/h，顯示此複合薄膜能做為一種良好的高溫型質子交換膜。

In this work, fluorine-containing polybenzimidazole (6F-PBI) was synthesized successfully. We added 1-hexyl-3methylimidazolium trifluoromethanesulfonate (HMI-Tf) into PBI solution to prepare a series of PBI/ionic liquids composite membranes. All composite membranes showed lower mechanical properties than pristine PBI membranes, but reached 0.0021 S/cm proton conductivity at 160 ℃ before phosphoric acid doped. Furthermore, phosphoric acid doped composite membranes, prepared with acid content of only 129%, could reach 0.015 S/cm proton conductivity at 160 ℃. Membrane electrode assemblies were fabricated with a size of 4 cm2 and a Pt loading of 1 mg/cm2. The composite membrane showed a little open circuit voltage change rate and proved stable in startup and shutdown tests (operated at 160 ℃ with 200 mA/cm2 for 12 h and then kept off for 12 h at room temperature). In long-term durability tests (operated at 160 ℃ with 200 mA/cm2 for 720 h), the composite membrane showed the cell voltage decay rate of 0.054 mV/h, indicating high stability during operation.

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