Synthesis and characterization of a fluorinated cross-linked anion exchange membrane

A fluorinated poly(aryl ether oxadiazole)s (FPAEO) was prepared from 2,5-bis(2,3,4,5,6-pentafluorophenyl)-1,3,4-oxadiazole (FPOx), 4,4′-isopropylidenebis(2,6-dimethylphenol) (TM-BPA) and 4,4′-(hexafluoroisopropylidene)diphenol (6F-BPA). The fluorinated cross-linked anion exchange membrane (FCAEM) was synthesized by bromination of FPAEO, quaternization with 1–methyl imidazole and cross-linking with N,N,N′,N′-tetramethyl-1,6-hexanediamine (TMHDA). Electrochemical characteristics, physical characteristics and mechanical properties of FCAEM were studied. It exhibited higher conductivity, better mechanical property, and dimensional stability. It showed the hydroxide ion conductivity about 1.7 × 10−2 S/cm, tensile strength about 28.02 MPa, water uptake about 51% and swelling ratio about 6% at 20 °C. The cross-linked anion exchange membrane could meet the requirement for alkaline electrolyte membrane fuel cells (AEMFCs).