交联型聚芳醚基阴离子交换膜的制备及性能研究

摘要

燃料电池由于能量转化率高、环境友好等优点,是最具应用前景的能量转化装置之一.阴离子交换膜作为燃料电池的核心部件,仍存在低电导、高溶胀等问题.这里,通过设计聚芳醚结构使其侧链末端含有碳碳双键,在Grubbs二代催化剂作用下进行烯烃复分解反应接枝离子基团,利用剩余不饱和双键在高温下的交联反应,制备出交联型聚芳醚基阴离子交换膜.由于亲水性侧链与疏水性主链的不兼容性,使膜内形成了有利于离子传输的微相分离结构,交联膜的最高电导率达到81.1 mS/cm(80℃).此外,交联结构能有效地抑制膜的溶胀,交联膜C-FPAE-PH-1.5在30℃下的溶胀率仅为7.51％,表现出优异尺寸稳定性.C-FPAE-PH-1.5膜在60℃下1 mol/L KOH水溶液中浸泡360 h后,保留了93.1％的电导率,表现出优异的耐碱性能.%Fuel cells are regarded as one of the most perspective energy conversion devices due to its high efficiency and low pollution.As a critical component of fuel cells,anion exchange membranes (AEMs)still meet the dilemma of low conductivity and high swelling ratio.Herein,crosslinked poly(arylene ether)s-based anion exchange membranes (AEMs) were prepared via olefin metathesis using Grubbs Ⅱ catalyst and crosslinking under thermal treatment.The as-prepared AEMs exhibit obvious microphase separated morphology since the hydrophilic side chain is immiscible with hydrophobic poly (arylene ether)s backbone.Finally,the crosslinked AEMs demonstrate a highest conductivity of 81.1 mS/cm at 80 ℃.The crosslinked structure is effective at enhancing the dimensional stability of the membranes.C-FPAE-PH-1.5 shows a low swelling ratio of 7.51％ at 30 ℃.Furthermore,the crosslinked AEMs show robust alkaline stability.C-FPAE-PH-1.5 remained 93.1％ of its original conductivity after immersing into a 1 mol/L KOH aqueous solution at 60 ℃ for 360 h.