磺化聚醚醚酮与壳聚糖共混制备直接甲醇燃料电池用质子交换膜

PREPARATION OF SPEEK AND SPEEK/CHITOSAN COMPOSITE PROTON-EXCHANGE MEMBRANES FOR APPLICATION IN DIRECT METHANOL FUEL CELLS

给出了不同磺化度下的磺化聚醚醚酮(SPEEK)用作质子交换膜的一系列性能,另外提出了一种新型的酸碱共混质子交换膜,其中,磺化聚醚醚酮和壳聚糖分别被选为酸性、碱性高分子电解质,并对所制备的质子交换膜的相关性能如质子传导性,甲醇渗透性,吸水率以及膜溶胀性、热稳定性等进行了表征,结果表明此种新型复合膜尽管在质子传导性能方面有所下降,阻醇性能改变不大,但是膜溶胀性和吸水率方面有了较大的改善.磺化度为71.4%的SPEEK与壳聚糖以5∶1摩尔比共混制备的质子交换膜,其性质可以与商品化的Nafion 117相媲美,有望在甲醇燃料电池中得到应用.

For application in direct methanol fuel cells, a series of SPEEK （sulfonated polyether ether ketone） membranes with different sulfonation degrees were tested, and a novel acid-base composite proton exchange membrane was prepared- SPEEK and chitosan were chosen as acidic and basic polyelectrolytes respectively. The properties of composite membranes, such as proton conductivity, methanol permeability, water uptake, membrane swelling and thermal stability, were tested- Although the proton conductivity reduced to some extent and the methanol permeability wasn’t improved, the water uptake and membrane swelling were significantly improved-Particularly, after chitosan was blended with SPEEK （sulfonation degree=71.4%） at a molar ratio of 1∶5, the prepared composite membrane exhibited comparable performances with Nafion 117, and such membranes are thus promising for application in fuel cells.