This report details the properties of fluorine-containing anion exchange membranes（AEMs） synthesized by chloromethylation and quaternization of fluorinated poly（arylene ether）s（FPAEs） based on decafluorobiphenyl...This report details the properties of fluorine-containing anion exchange membranes（AEMs） synthesized by chloromethylation and quaternization of fluorinated poly（arylene ether）s（FPAEs） based on decafluorobiphenyl and bisphenol A. Meanwhile, we compared their properties with those of their non-fluorinated counterparts, Udel-based AEMs. The reactivity of the chloromethylation of fluorinated poly（arylene ether）s was lowered by the strong elec- tron-withdrawing group, per-fluorinated biphenyl residue. Therefore higher temperature, more chloromethylation reagent, and longer reaction time were needed in the chloromethylation of FPAEs. Because of the hydrophobicity of fluorine, the swelling of FPAEs was depressed. In the FPAE-based AEMs, the water uptake of FPAE-1 membrane（F-1） was just 30%. There is a strong correlation between water uptake and conductivity for both Udel- and FPAE-based AEMs. Among all the membranes, the water uptake and the conductivity of FPAE-3 membrane（F-3） could reach up to 100% and 13.47 mS/cm respectively at 30 ℃. The mechanical properties of FPAE-based AEMs at room tempera- ture were worse than those of Udel-based ones because of the weak intermolecular interaction caused by the low po- larizability of fluorine. However, their high temperature mechanical properties are better, which can be explained in terms of low swelling.展开更多
基金Supported by the National Natural Science Foundation of China（Nos.51173178, 514＂73157, 21304093）.
文摘This report details the properties of fluorine-containing anion exchange membranes（AEMs） synthesized by chloromethylation and quaternization of fluorinated poly（arylene ether）s（FPAEs） based on decafluorobiphenyl and bisphenol A. Meanwhile, we compared their properties with those of their non-fluorinated counterparts, Udel-based AEMs. The reactivity of the chloromethylation of fluorinated poly（arylene ether）s was lowered by the strong elec- tron-withdrawing group, per-fluorinated biphenyl residue. Therefore higher temperature, more chloromethylation reagent, and longer reaction time were needed in the chloromethylation of FPAEs. Because of the hydrophobicity of fluorine, the swelling of FPAEs was depressed. In the FPAE-based AEMs, the water uptake of FPAE-1 membrane（F-1） was just 30%. There is a strong correlation between water uptake and conductivity for both Udel- and FPAE-based AEMs. Among all the membranes, the water uptake and the conductivity of FPAE-3 membrane（F-3） could reach up to 100% and 13.47 mS/cm respectively at 30 ℃. The mechanical properties of FPAE-based AEMs at room tempera- ture were worse than those of Udel-based ones because of the weak intermolecular interaction caused by the low po- larizability of fluorine. However, their high temperature mechanical properties are better, which can be explained in terms of low swelling.
