Imidazolium functionalized poly(aryl ether ketone) anion exchange membranes having star main chains or side chains

Anion exchange membranes with star main chains or side chains were prepared by grafting the 1-butyl-2-methylimidazole and/or 1-aminopropyl-2-methyl-3-butylimidazolium hydroxide onto branched or linear poly(aryl ether ketone) polymers. In order to know the influence of the star structures on the physicochemical properties of the prepared membranes, comprehensive characterizations were made including ion exchange capacity, conductivity, mechanical property and alkaline stability. All the membranes exhibit conductivities of about 40 mS cm(-1) at 60 degrees C and about 60 mS cm(-1) at 80 degrees C, respectively. The durability of the membranes in alkaline medium was detected by monitoring the changes in conductivity, ion exchange capacity and contact angle with water. The results indicate that the introduced star structures of both main chains and side chains are effective to enhance the tensile strength and alkaline stability of the membranes. The membranes with star main chains exhibited a tensile stress at break of 45 MPa and retained a conductivity of 36.1 mS cm(-1) at 60 degrees C after exposed to 1 M KOH at 80 degrees C for 300 h. (C) 2018 Elsevier Ltd. All rights reserved.