A facile functionalized routine for the synthesis of imidazolium-based anion-exchange membrane with excellent alkaline stability

A facile functionalized routine was designed for the synthesis of novel imidazolium-based poly(ether sulfone) (Im-PES) anion-exchange membrane (AEM). The special matrix, a type of PES with double bonds (PES-DB), was chosen to react directly with the functional reagent, 1-allyl-3-methylimidazolium chloride (AmimCl). This method eliminates the disadvantages of conventional functionalized approaches, in which PES matrix should be pre-treated by chloromethylation or bromination reactions, making the whole routine complex and inefficient. Then, the structures and properties of the membranes were investigated. Apart from the stable structure and electrochemical performances, the alkaline stability was attractive. The membrane presents a high ionic conductivity (up to 9.21 x 10(-2) S cm(-1)) with a low methanol permeability (as low as 1.56 x 10(-7) cm(2) s(-1)). What is more, it can still retain around 83.6% of the initial ionic conductivity after treated in alkaline condition for 300 h. These results indicate that the simple functionalized routine is effective to synthesize the Im-PES and the membrane may possess potential applications for alkaline fuel cells (AFCs). (C) 2016 Elsevier B.V. All rights reserved.