Polycyclotriphosphazene Derivative Grafted and NanometerY2O3 Doped SPEEK Composite Membrane for DMFC

A type of polycyclotriphosphazene derivative (PCTPD), hexasulfanilic acid polycyclotriphosphazene (HSACP) and HSACP grafting SPEEK, sulfonated poly[2-(petachloropolycyclotriphosphazene-oxy)] etheretherketone (SPPSACPEEK) were synthesized, which were characterized by FTIR and 31P NMR. Then three types of composite membranes such as HSACP grafting SPEEK, HSACP blending SPEEK, and nano Y2O3 doping and HSACP grafting SPEEK, respectively, were continuously prepared by solution-casting method. Comparing to SPEEK membranes with different amount of HSACP grafted or blended, grafting 15 wt% HSACP and doping 10 wt% nano Y2O3 SPEEK membrane conducted outstanding overall behavior of proton conductivity reaching 3.18 × 10-2 S/cm at 90 oC which was merely junior to SPEEK with 15 wt% HSACP grafted, methanol permeability coefficient getting 9.46 × 10-8 cm2·s-1, swelling degree of 20.9% and solid residue of 98.98% which was superior to all specimen.