聚轮烷基交联型离子膜设计制备及应用研究

To minimize the dilemma of balancing the ionic conductivity and swelling resistance of ion exchange membranes (IEMs), this project is willing to develop novel polyrotaxane-based polymer electrolytes via host-guest recognition between crown cavity and secondary ammonium salts. The relationship between polymer architecture, membrane morphology and properties of the resulting IEMs will be investigated by detecting the construction of polyrotaxane crosslinking networks and the mobility of the crosslinks. We will perform the study on the effect of the crosslinking networks on swelling resistance of IEMs, and further investigate the effect of mobile behavior of crosslinks on ion transport. This study tends to push down the limit of covalent crosslinking for preparation of IEMs, and to boost the understanding of a new ion transport principle through IEMs. Thus, this in-depth study will provide persistent enthusiasm for membranologists who are interested in either the fundamental understanding of structure–property relationships or practical applications in fuel cells and other membrane separation processes.

本课题针对目前燃料电池用离子膜电导率和耐溶胀性稳定性无法兼顾这一难题，根据超分子研究领域前沿的基于轮烷的主客体识别技术，设计合成聚轮烷基交联型离子膜并进行结构-形貌-性能关联研究，探索聚轮烷基交联网络形成过程及在不同pH值或温度诱导下交联链段局部自由移动的条件,研究交联网络对膜耐溶胀性能的影响，及交联链段局部自由移动性对水合质子或水合氢氧根离子空间构型转变的影响规律，阐明聚轮烷交联网络对膜离子传导的增强机制。本课题研究有望实现离子膜制备的新突破，而且还能建立一个新的高效膜内离子传导模型，为离子膜在膜分离领域广泛应用,特别是燃料电池应用提供强有力的理论支持和技术支撑。

本课题针对目前燃料电池用离子膜电导率和耐溶胀性稳定性无法兼顾这一难题，从共价键结合侧链型聚合物结构出发,成功设计制备出系列侧链型离子膜，阐明侧链柔性对自组装构建规整传导形貌影响；基于此将非共价键相互作用,如离子-偶极相互作用、偶极-偶极相互作用引入聚合物体系，增强功能链段自组装能力揭示非共价键相互作用在诱导离子膜规整形貌构建的重要作用。为进一步精准调控非共价键作用，开发出基于轮烷单元具有可自由穿梭侧链结构的离子交换膜，阐明轮烷单元促进微相分离的发生和离子通道的构建，提出聚轮烷网络穿梭特性对膜离子传导的增强机制。通过项目实施，在Angew Chem Int Ed, AIChE J.等期刊发表研究论文12篇，申请发明专利4件。项目负责人入选Science Bulletin编委会成员，获2020年度中国化工学会侯德榜化工科技青年奖。共培养博士2人，硕士3人。