全氟质子交换膜的化学降解及其稳定化研究进展  

Progress of Chemical Degradation and Stabilization of Perfluocarbon Proton Exchange Membrane

作　　者：程宇婷[1] 唐浩林[1] 潘牧[1] 

机构地区：[1]武汉理工大学材料复合新技术国家重点实验室,武汉430070

出　　处：《材料导报》2011年第21期29-33,42,共6页Materials Reports

基　　金：国家自然科学基金(50802072);教育部博士点新教师基金(200804971052);教育部留学回国人员科研启动费资助

摘　　要：从化学退化行为、退化机理以及化学耐久性改善措施方面对全氟质子交换膜的化学耐久性进行了总结,目前的进展表明质子交换膜失效的主要原因是自由基攻击高分子的缺陷末端基团,将羧酸基团还原成二氧化碳和F离子,从而导致树脂高分子开链式分解;羟基自由基来源于双氧水的分解,其产生速度随温度升高而加快、膜中的氢氧气体扩散随湿度降低而增大。因此,在膜中掺杂自由基捕获剂可减少双氧水和自由基的浓度,或者消除高分子的末端缺陷基团有利于提高膜的化学耐久性。This paper reviews the available literature regarding the chemical degradation behavior, degradation mechanism and stabilization strategies of the perfluocarbon proton exchange membranes. Peroxide radicals that generated from hydrogen peroxide remains the most likely culprit for membrane chemical degradation. The leading mechanism for degradation of commercially-available PEM membranes is initiated by abstraction of a hydrogen atom from residual carboxylic acid ends on PTFE backbones and then unzipped the repeatted main chain. Incorporation of radical scavenger, such as cerium oxide, in the perfluocarbon proton exchange membranes is helpful to minish the concentration of peroxide radicals, and thus reduce membrane degradation. Reduction of the carboxylic acid ends by fluorination or reforming the defect groups to a stable struture, such as -CH, can substantially reduce the chemical degradation and increases the durability.

关 键 词：全氟质子交换膜 耐久性 化学退化 稳定化 

分 类 号：TQ342.62[化学工程—化纤工业]