Highly proton conductive and highly reliable polybenzoxazole with peculiar microporous structure for high-temperature and water-free PEMFC systems

摘要

The novel high-temperature polymer electrolyte membranes containing benzoxazole moieties were fabricated via thermal rearrangement mechanism over 350 deg C using hydroxyl-containing polyimide(6-FPI)membranes,and subsequent acid impregnation.Especially,the thermal treatment at 450 deg C for 1 h resulted in a polybenzoxazole(6-FPBO)membrane without any hydroxyl groups.The resulting 6-FPBO membrane contained a microporous structure with high surface area(535 m~2/g),fractional free volume(0.309)and microvoid fraction(approx 0.38)substantially similar to that(0.47-0.5)of most open zeolites.