Department of Chemical and Biological Engineering, Seoul National University, 599 Gwanak‐ro, Gwanak‐gu, Seoul 151‐744, South Korea
Abstract:
PBI‐LiHzS composite membranes were prepared by casting N,N'‐DMAc solutions containing PBI and LiHzS, where the LiHzS contents in the membranes were between 2.5 and 10 wt.‐%. LiHzS was obtained by reacting hydrazine sulfate and lithium carbonate in water. PBI‐LiHzS composite membranes were thermally stable up to approximately 300 °C and their acid‐absorbing capabilities were comparable to those of the pure PBI membranes. The proton conductivity of PBI‐LiHzS composite membranes (2.12 × 10?2 S · cm?1 at 180 °C and 0% RH) was higher than that of pure PBI membranes when used at the same acid doping levels. The mechanical stability of the composite membranes having less than 5 wt.‐% of LiHzS was found to be close to that of pure PBI membranes.
