胺化条件对季铵化PPEK膜性能的影响

Effects of amination conditions on membrane properties of quaternized poly(phthalazinone ether ketone)

以氯甲基化杂萘联苯聚醚酮(CMPPEK)为膜材料,通过溶液法制备了CMPPEK基膜,然后将其浸泡在三甲胺水溶液中进行季铵化反应得到季铵化杂萘联苯聚醚酮(QAPPEK)阴离子交换膜。比较了CMPPEK和QAPPEK的热失重性能,CMPPEK的5%热失重温度为330℃,QAPPEK的5%热失重温度为260℃,QAPPEK的5%热失重温度与CMPPEK的相比降低了70℃。考察了三甲胺浓度、胺化时间、胺化温度等反应条件对QAPPEK膜性能的影响。结果表明:三甲胺的质量分数为33%、胺化时间为12h、胺化温度为40℃时,得到的QAPPEK膜表现出了较优异的性能,其IEC值达1.64mmol/g,在2mol/LVOSO4+3mol/LH2SO4的混合溶液中测得的面电阻为0.73Ω·cm2,应用于全钒液流电池(VRB)中,电池的能量效率高达85.9%,电流效率为98.4%,电压效率为87.3%。

A novel anion-exchange membrane material quaternized poly （phthalazinone ether ketone） （QAPPEK） was prepared with trimethylamine （TMA） by inducting quaternary nitrogen groups into the chloromethylated poly （phthalazinone ether ketone） （CMPPEK）. It is found that the thermal performance of QAPPEK decreases slightly compared with CMPPEK. The temperature of 5% weight loss of CMPPEK and QAPPEK are 330 ℃ and 260 ℃ respectively. The effects of amination concentration, amination temperature and amination time on the properties of QAPPEK membrane were investigated. The results show that the QAPPEK membrane has the best performance prepared at 33% trimethylamine under 40 ℃ amination temperature for 12 h, and the ion exchange capacity （IEC） and membrane area resistance （R） tested in 2 mol/L VOSO4＋3 mol/L H2SO4 can reach 1.64 mmol/g and 0.73 W.m2, respectively. When QAPPEK membrane is applied to vanadium redox flow battery, the energy efficiency, current efficiency and voltage efficiency of the battery can reach 85.9%, 98.4% and 87.3%, respectively.