一种新型磺化聚酰亚胺质子交换膜的合成与表征

质子交换膜是质子交换膜燃料电池膜电极的核心部件之一，它的性能好坏对整个系统的运行起着至关重要的作用．目前在质子交换膜燃料电池中普遍采用的质子交换膜材料是全氟磺酸系列薄膜，这类材料具有较高的质子传导率、化学及机械稳定性，但用于直接甲醇燃料电池（DMFC）时则存在甲醇渗透、导致燃料电池输出性能大大降低的问题

Preparation and characterization of novel sulfonated polyimide proton conductive membrane

Proton conductive membrane plays a decisive role in polymer electrolyte membrane fuel cell systems. To prepare polymer electrolyte membranes for direct methanol fuel cell(DMFC), a series of novel sulfonated polyimides(SPI) were synthesized from sulfonated diamine，2,5-bis(4-aminophenoxy)benzene sulfonic acid (S-TBDA) with 3,3′,4,4′- benzophenone tetracarboxylic dianhydride (BTDA) and non-sulfonated diamine(ODA) via direct polymerization in this study.The sulfonation degree of the polymers was controlled by changing the molar ratio of the monomers. The obtained SPI membrane was then characterized with FTIR and the influence of sulfonation degree on proton conductivity, methanol permeability and other properties were investigated.With the increase of sulfonation degree，the proton conductivity and methanol permeability increased gradually.The proton conductivity of the SPI membranes ranged from 3.9×10^-3 to 3.4×10^-2 S•cm^-1 and the methanol permeability was less than 1×10^-7 cm² •s^-1.The experiment result indicated the potential of such proton conductive membrane for fuel cell applications.