本研究之目的是著重於高溫型質子交換膜燃料電池(High temperature proton exchange membrane fuel cell, HT-PEMFC)電解質薄膜之開發。利用4,4'-二氨基二苯醚(4,4’-Oxydianiline, ODA)與4,4'-氧雙鄰苯二甲酸酐(4,4’-Oxydiphthalic anhydride, ODPA)合成之聚亞醯胺酸(Polyamic acid)作為有機之前驅物；將磷酸三甲酯(Trimethyl phosphate, TMP) 與四乙基矽酸鹽(Tetraethyl orthosilicate, TEOS)經由適當的水解反應，得到無機相前驅物。均勻混合有機與無機之前驅物後，利用溶膠-凝膠(sol-gel)法合成出含磷矽酸鹽 (Phosphor-silicate)與線性芳香族聚亞醯胺(Polyimide)之有機/無機質子傳導混成薄膜。藉由有機/無機混成薄膜結構與反應機制的瞭解，來改善成有機/無機薄膜之成膜製程；並探討不同磷-矽組成之有機/無機薄膜對熱性質、含水率、甲醇滲透、化學穩定性及質子傳導度之性質分析。
由in-situ FTIR研究顯示，ODA與ODPA在30 oC需要一天才能使形成PAA之反應趨於完成；藉由NMR圖譜得知，TMP在室溫下之水解反應性極低，而TMP在60 oC反應溫度下能有較佳之水解反應。在成膜溫度120 oC下所合成之有機/無機混成薄膜(有機：無機重量比=5:5)，其結構經由FTIR與NMR可知，富有機相為PAA/PI與富無機相為H3PO4/SiO2之結構，而有機/無機間的介面則有氫鍵與共價鍵。
由TGA/DTA得知有機/無機膜擁有良好的熱性質，其最大熱裂解溫度皆在600 oC左右；而有機/無機薄膜之抗張應力皆高於423 kgf/cm2。甲醇滲透度則以O5-P5Si5表現最佳，約為11.92 × 10-9 cm2/s比商業化Nafion 低兩個階層，擁有最佳的化學穩定性，而其質子傳導度在30 oC、相對濕度100 %環境下有9.53× 10-6 S/cm。利用水-蒸汽管理系統處理之薄膜，其導電度明顯提升，其中TO5-P10Si0在溫度110 oC、濕度100 %的環境下為1.99 × 10-3 S/cm。

The main objective of this study is to synthesize the organic/inorganic hybrid membranes for high temperature proton exchange membrane (HT-PEMFC) applications. 4,4’-Oxydianiline (ODA) and 4,4’-Oxydiphthalic anhydride (ODPA) were chosen in order to synthesize the organic component Polyamic acid (PAA). The PAA was then reacted with the inorganic precursors TMP (Trimethyl phosphate) and TEOS (Tetraethyl orthosilicate) to form the organic/inorganic hybrid membrane by a sol-gel method. The resultant membranes have proton conductivity contributed from inorganic structure and good flexibility from organic component. Various analytical techniques were used to characterize the structure and proton conduction mechanism, and to discuss the effect of different phosphorus-silicon molar content on water uptake, methanol permeability, mechanical properties, thermal- properties, chemical stability, and proton conductivity.
The in-situ FTIR spectral results revealed that the highest PAA formation was achieved once the reaction between ODA and ODPA at 30 oC was allowed for one day. It was observed that TMP can be hydrolyzed at 60 oC for 1 day to form the PO(OH)3 completely. At the curing temperature of 120 oC, the organic-rich region and inorganic-rich region of the organic/inorganic hybrid membrane (weight ratio=5:5) were found to be PAA/PI and H3PO4/SiO2, respectively. The interface of organic and inorganic-region formed both hydrogen and covalent bonds.
From the TGA/DTA results, it was observed that the highest decomposition of organic/inorganic hybrid membrane with different P and Si content was occurred at 600 oC. From the mechanical analysis, it was found that the organic/inorganic hybrid membrane possessed the lowest stress about 423 kgf/cm2. This value is higher than that of the operating press during the fabrication of membrane electrode assembly (MEA). It indicates that this series of membranes were suitable for making MEA. Among the hybrid membrane, the O5-P5Si5 had lower methanol permeability about 2 order when compared to that of the commercial Nafion 117 membrane. The methanol permeability of O5-P5Si5 membrane was found to be 11.92 × 10-9 cm2/s and the conductivity was found to be 9.53× 10-6 S/cm at 110 oC, related humidity 100 %. It was also exhibited promising chemical stability. There was a clear increase in the proton conductivity of the organic/inorganic hybrid membrane by using water/vapor management. The TO5-P10Si0 membrane showed the best proton conductivity of about 1.99×10-3 S/cm at 110 oC, related humidity 100%.

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