以芘(py)为支化基团,基于对三联苯(TP)和N-甲基-4-哌啶酮(NM4P)单体,经强酸催化聚合得到超支化芘基聚三联苯哌啶聚合物(h-PTPE-py-n).通过调整支化基团和三联苯的比例,可以得到不同支化度的超支化聚三联苯哌啶阴离子交换膜h-PTP-py-n.对该聚合物的化学结构、热性能、力学性能、离子传导性质进行了系统表征和测试,并将该类型膜应用于阴离子交换膜电解水(AEMWE)器件,评估其在实际工况下的运行基本表现.结果表明,芘引入导致的支化有效提高了阴离子交换膜的力学性能和尺寸稳定性,所制得的阴离子交换膜在80℃下的氢氧根离子传导率最高达到168.0 mS/cm,应用到AEMWE中时,h-PTP-py-n展示出了优异的导电性,在3 V条件下电流密度达到1.95 A/cm2,并且能稳定运行超过90 h.
Abstract
Hyperbranched poly(terphenyl piperidine) with pyrene as the branched core is synthesized by co-polymerization of p-terphenyl,N-methyl-4-piperidone,and pyrene in the presence of acid. Anion exchange membranes (AEMs) with different degrees of branching are prepared by controlling the ratio of branching pyrene to backbone p-terphenyl. The chemical structure,thermal stability,mechanical feature,and ionic conductivity of the polymers are thoroughly studied. After casting,the AEMs are further applied into AEM water electrolyzers (AEMWEs) to evaluate their device performance under practical working conditions. The mechanical features and dimensional stability of AEMs have been improved by branching. The thermal stability of the AEMs is close to that of the linear control polymer-based membrane. The tensile strength of as-prepared AEMs reaches 73.5 MPa,which is 72％ higher than the linear polymer-based membrane (42.8 MPa). The ionic conductivity of as-prepared AEMs reaches 78.2 mS/cm at room temperature and 168.0 mS/cm at 80℃. After branching,the water content (81.9％ at 80℃) and swelling ratio (47.1％ at 80℃) of as-prepared AEMs decrease significantly in comparison with linear control polymer-based AEM (water content:139.2％,swelling ratio:82.7％). In AEMWEs,the devices exhibit excellent electric current density of 1.95 A/cm2 at 3 V and stable operation over 90 h.
关键词
阴离子交换膜/超支化结构/碱性电解水/聚芳基哌啶/芘
Key words
anion exchange membrane/hyperbranched structure/alkaline water electrolysis/poly(aryl piperidinium)/pyrene
维普
万方数据