High-temperature polymer electrolyte membranes based on poly(2,5-benzimidazole) (ABPBI) and POSS incorporated ionic liquid

This paper reported a method to modify polyhedral oligomeric silsesquioxane (POSS) particle into POSS ionic liquid (POSS-IL) and its incorporation into ABPBI/H3PO4 system to enhance the proton conductivities and mechanical properties of the membranes simultaneously. It was found that good dispersion of POSS-IL in the polymer matrix increased the tensile strength and Young’s modulus of the membranes. For membranes with the same H3PO4 content, the incorporation of POSS-IL increased the conductivities of the membranes by about two orders of magnitude. The highest conductivity was achieved by ABPBI/10 wt% POSS-IL composite membrane, which was 7.6×10-2 S/cm at 200 °C.