Alkaline anion exchange ionomer (AEI),as the ion conductor and binder for the catalyst layer of anion exchange membrane fuel cell (AEMFC)membrane electrode assembly,plays an important role in AEMFC's performance and stability.Styrene-ethylene/butylene-styrene (SEBS) was chosen as the starting material and pendant quaternary ammonium-based ionomers-QASEBS was prepared via chloromethylation,quatemization and alkalization,which was insoluble in water,but could dissolve in low boiling point solvent,such as the mixture of n-propyl alcohol and tetrahydrofuran.The QASEBS membrane was prepared by casting,and the membrane water uptake,swelling ratio,ion exchange capacity and hydroxide conductivity was characterized.The results show that the membrane water uptake and swelling ratio are 57％ and 20％ at 25 ℃,respectively;the ion exchange capacity is 0.21 mmol/g at 30 ℃;the hydroxide ion conductivity reaches 1.62 x 10-2 S/cm at 80 ℃.The hydrogen/oxygen AMFC using this AEI exhibites good performance and durability.The open circuit voltage is 1.04 V and the maximum power density is 153 mW/cm2.Besides,during the durability test,the initial cell voltage is above 0.7 V at 100 mA/cm2.After 30 hours,the cell voltage almost remains unchanged.%碱性阴离子交换树脂作为碱性膜燃料电池膜电极催化层中的离子导体和粘结剂,对构建稳定的立体化电极催化层结构以及碱性膜燃料电池的性能和稳定性具有重要影响.以聚(苯乙烯-乙烯-丁烯-苯乙烯)三嵌段聚合物(SEBS)为基材,经过氯甲基化、三乙胺季胺化、碱化,制备了不溶于水,但能够溶于低沸点溶剂(正丙醇和四氢呋喃混合溶剂)的阴离子交换树脂(AEI).通过流延法将AEI成膜,并且测试了膜的吸水率、溶胀率、离子交换容量和氢氧根离子电导率,结果表明:膜的溶胀率为20％,离子交换容量为0.21 mmol/g,在80℃时离子电导率达到16.2 mS/cm.用这种AEI制备电极组装电池,在H2/O2碱性膜燃料电池的测试中表现出良好的性能和稳定性,电池的开路电压达到1.04 V,峰值功率密度达到153 mW/cm2;在100 mA/cm2电流密度条件下的稳定性测试中,初始电池电压在0.7 V以上,电池运行30h后,电池电压未发生明显降低.
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