膜科学与技术

柔性含醚季鏻侧链聚砜阴离子交换膜研究

作者：崔福军，刘勇，张扬，张帆，吴雪梅，贺高红

单位： 1. 大连理工大学盘锦产业技术研究院辽宁省化学助剂合成与分离省重点实验室，辽宁盘锦，124221；2.大连理工大学精细化工国家重点实验室膜科学与技术研究中心化工学院，辽宁大连, 116024

关键词：燃料电池；阴离子交换膜；季鏻碱性基团；氢氧根离子电导率；碱稳定性

出版年,卷(期):页码： 2022,42(2):16-24

摘要：

燃料电池为氢能高效利用提供了解决方案，阴离子交换膜是燃料电池的核心部件。季鏻碱性功能基团常连接大体积供电基团提升耐碱性，但阻碍OH-传导。本文提出具有高传导和碱稳定性的柔性含醚季鏻功能侧链，季鏻阳离子与聚砜主链间的含醚脂肪间隔基团增强了侧链柔性，促进季鏻功能基团聚集；醚氧原子比N、C原子电负性更强，可提高亲水性；季鏻连接的三（2,4,6-三甲氧基苯基）大空间位阻通过阻隔OH-进攻提升膜的碱稳定性。结果表明，柔性含醚季鏻侧链型聚砜阴离子交换膜显示出极低的溶胀率（约10 %），较高的氢氧根离子电导率（80 oC下为79.6 mS cm-1）和优异的耐碱性（80 oC、1 mol/L NaOH热碱溶液浸泡168h后，氢氧根离子电导率保持率超过90%，而拉伸强度仅下降约2%）。

Fuel cells provide solution to efficiently application of hydrogen energy. Anion exchange membrane (AEM) is one of the core components of anion exchange membrane fuel cell, and the selection of functional groups plays a crucial role in its performance. By bonding large sterically groups to quaternary phosphonium cation, the alkali stability of the quaternary phosphonium can be achieved, however, hydroxide conductivity is inevitably hindered. In this work, a flexible ether bond quaternary phosphonium side chain structure is proposed to simultaneously improve conductivity and alkali stability of quaternary phosphonium based AEMs. The ether bond containing aliphatic spacer between quaternary phosphonium cation and the polysulfone backbone enhances the flexibility of the functional side chain, and thus improves the aggregation of quaternary phosphonium cations. The stronger electronegativity of the ether O atom as compared with the N and C atoms increases hydrophilicity of the membranes. The large steric hindrance of the tris(2,4,6-trimethoxyphenyl) phosphine group could block the attack of hydroxide ions, therefore improve alkali stability. The flexible ether bond quaternary phosphonium side chain based polysulfone AEMs exhibit extremely low swelling ratio (about 10%), high hydroxide conductivity (79.6 mS/cm at 80 oC) and excellent alkali stability (about 90% conductivity retention and 98% strength retention after immersing in 80 oC, 1MNaOH for 168h).

崔福军(1970-)，男，河北承德人，研究方向为荷电膜及膜过程、粘合剂等，Email：1012293273@qq.com

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