超强酸催化Friedel-Crafts反应制备无醚磺化聚芳基质子交换膜  

Ether-free Sulfonated Polyarylene-Based Proton Exchange Membranes by Superacid-catalyzed Friedel-Crafts Reaction

作　　者：黄梓俊 龙志 陈策能 徐珂 钱彬彬 任艳蓉[1] 丁涛[1] 房晓敏[1] Zi-jun Huang;Zhi Long;Ce-neng Chen;Ke Xu;Bin-bin Qian;Yan-rong Ren;Tao Ding;Xiao-min Fang(College of Chemistry and Molecular Sciences,Henan University,Kaifeng 475001;Shenzhen Institute of Advanced Technology,Chinese Academy of Sciences,Shenzhen 518055;Faculty of Materials Science and Energy Engineering,Shenzhen University of Advanced Technology,Shenzhen 518000)

机构地区：[1]河南大学化学与分子科学学院,开封475001 [2]中国科学院深圳先进技术研究院,深圳518055 [3]深圳理工大学材料科学与能源工程学院,深圳518000

出　　处：《高分子学报》2024年第12期1730-1741,共12页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号52203284);广东省基础与应用基础研究基金自然科学基金面上项目(基金号20825265044);深圳市科技计划(项目号GJHZ20220913143801003,RCBS20221008093057026,RCBS20221008093303001,RCBS20210609104609043);中国科学院科技服务网络计划-黄埔专项(项目号STS-HP-202205)资助.

摘　　要：通过三氟甲磺酸催化Friedel-Crafts反应,合成了含有三氟异亚丙基的无醚聚芳前驱体聚合物.考察了不同芳基单体、电子云密度和空间位阻等因素对前驱体聚合物分子量的影响,并优化反应条件,实现了前驱体的合成.特别是,以联苄和三氟丙酮为原料合成的前驱体聚合物PAAF,展现出了高分子量(Mw=201 kDa,Mn=63 kDa)特性;随后,经氯磺酸三甲基硅烷基酯后磺化制备了sPAAF,其不仅保持了高分子量(Mw=201 kDa,Mn=63 kDa),还具备了高离子交换容量(2.40 mmol/g).在80℃完全水合状态下,质子电导率最高可达102 mS/cm,热分解温度为258℃,化学稳定性良好,在芬顿测试后质量衰减率仅为11%,表明该系列材料具有良好的化学稳定性.本研究旨在通过引入不同的亚苯基结构和功能基团,深入探讨聚合物结构与膜性能之间的构效关系,为开发低成本、高性能的无醚聚苯基质子交换膜材料奠定基础.Proton exchange membrane(PEM)is one of the key components of PEM fuel cells.Sulfonated poly(arylenen ether)-based PEMs have gained much more attention due to easy synthesis and excellent mechanical and thermal properties.However,these PEMs containing ether bonds,which are vulnerable to free radical,show poor oxidative stability.Ether-free polyarylene-based polymer has become the most promising one,giving that no heteroatom is contained on the backbone.Up to now,it has been synthesized only by metalcatalyzed polymerization,Diels-Alder polymerization and superacid-catalyzed polymerization.Superacidcatalyzed polymerization is an easy approach to providing the polymer with pendent alkyl sulfonic acid rather than aryl sulfonic acid.Herein,ether-free polyarylene-based precursors containing trifluoroisopropylidene were successfully synthesized via the trifluoromethanesulfonic acid-catalyzed Friedel-Crafts reaction and then postsulfonated to obtain ether-free polyarylene-based PEM containing arylene sulfonic acid and trifluoroisopropylidene on the backbone.The effects of the substituents,electron cloud density,and steric hindrance on the molecular weight of the precursor polymers were investigated.The arylene-based monomer with high electron cloud density provided high reaction activity and molecular weight(Mw>200 kDa),such as fluorene and 9,9-diphenylfluorene,but those after post sulfonation cannot provide flexible membranes due to the rigidity of mainchain.Considering to the balance between electron cloud density and rigidity,a precursor polymer consisting of trifluoroisopropylidene and bibenzyl(PAAF)demonstrated a high molecular weight of 201 kDa and provided flexible membrane after post-sulfonation.Giving that PAAF was not dissolved in concentrated sulfonic acid and easily precipitated from dichloromethane after dropping chlorosulfonic acid,those common post-sulfonation was useless.Chlorosulfonic acid trimethylsilyl ester was used to obtain sulfonated poly(arylene alkylene)-based polymers(sPAAF).sPAAF with various io

关 键 词：聚合物合成 质子交换膜 无醚聚苯 磺酸功能化 

分 类 号：TM911.4[电气工程—电力电子与电力传动] TB383.2[一般工业技术—材料科学与工程] O643.3[理学—物理化学]