Synthesis And Performances Of Poly(ether Sulfone)Anion-exchange Membrane For Alkaline Fuel Cells

Due to the fast economic development and limited availability of fossil fuels, the development of technology for clean, high efficiency and alternative energies has been becoming more and more important. Among them, the high-efficiency and environmentally friendly fuel cells have been regarded as one of the most promising power generation technologies. As is known to all, the polymer electrolyte membranes(PEMs) are the key component of fuel cell, which could transport ions and impede the fuel and oxidant. These types of membranes are divided into the proton exchange membranes and anion exchange membranes. Compared with the proton exchange membranes, anion exchange membranes have more advantages. It presented fast oxidation reaction rate for alkaline fuel celsl and non-precious metals could be used as electrodes. In this paper, several types of novel AEMs derived from poly(ether sulfone)s were successfully prepared with a simple approach and finally their properties were also evaluated.First, anion exchange membranes based on quaternary ammonium groups(QA) and imidazolium group were prepared via polycondensation, bromination(NBS), functional and the following hydroxide exchanging. These results showed that imidazoliumfunctionalized anion exchange membranes had higher ionic conductivity and better chemical stability in alkaline environment.In the following steps, a facile functionalized routine was designed for the synthesis of novel crosslinked imidazolium-based poly(ether sulfone)(Im-PES) anion-exchange membranes(AEMs). The main purpose was that a type of PES with double bonds was chosen to react directly with the functional reagent, 1-allyl-3-methylimidazolium chloride(AmimCl). By the investigation of the structures and properties, these membranes presented a high ionic conductivity(up to 9.21×10-2 S cm-1). Moreover, the ionic conductivity could still retain around 83.6% of after treated in alkaline condition(2 M NaOH solutions) for 300 hours. These results indicate that the simple functionalized routine is effective to synthesize the Im-PES membranes, which may possess potential applications for alkaline fuel cells.