叠氮—炔烃点击化学合成含季铵化长烷基侧链的聚苯醚

Synthesis of poly(2,6-dimethyl-1,4-phenylene oxide)s containing quaternized long alkyl side chains via azide-alkyne click chemistry

碱性阴离子交换膜(AAEM)作为碱性阴离子交换膜燃料电池的核心部件,能阻隔阴阳两极气体和传导氢氧根离子,对电池性能起关键作用。为发展简单、高效的方法用于制备侧链型AAEM材料,提出利用叠氮—炔烃点击化学合成新型AAEM材料。首先以商业化的聚(2,6-二甲基-1,4-苯醚)为原料,经溴化、叠氮化反应,制得具有不同叠氮化度的叠氮化聚苯醚(APPO-x)。以商业化的1,5-二溴戊烷、丙炔醇和三甲胺为初始原料,经亲核取代反应、季铵化反应,制得含端炔基的季铵化长烷基侧链前体(TMPAB)。最后通过APPO-x与TMPAB间的点击化学反应,制得具有不同季铵化程度的含季铵化长烷基侧链的聚苯醚(LQ-PPO-x)。1 H NMR和FT-TR分析确认了季铵化侧链前体、聚合物的结构。热重分析表明,所得聚合物LQPPO-x具有良好的热稳定性。

Alkaline anion exchange membrane(AAEM)is one of the key components for alkaline anion exchange membrane fuel cells.AAEM can prevent the mixing of the fuel and oxidant gas and conduct hydroxyl ions,which plays an important role on the properties of fuel cells.To develop facile and efficient methods to prepare side-chain-type AAEMs,the preparation of novel AAEMs via the azide-alkyne click chemistry was proposed in this paper.First,azided poly(2,6-dimethyl-1,4-phenylene oxide)s(APPO-x)with different degrees of azidation were prepared from commercially available poly(2,6-dimethyl-1,4-phenylene oxide)s by the bromination and azidation reactions.Then,the quaternized long alkyl side chain precursor(TMPAB)with an alkynyl end group was synthesized from commercially available 1,5-dibromopentane,propargyl alcohol and trimethylamine by the nucleophilic substitution and quaternization reactions.Lastly,the poly(2,6-dimethyl-1,4-phenylene oxide)s containing quaternized long alkyl side chains(LQPPO-x)were prepared by click chemistry between TMPAB and APPO-x.The structures of the side-chain precursor and polymers were comfirmed by 1 H NMR and FT-IR.Thermogravimetric analysis showed that the LQPPO-x polymers have good thermal properties.