制备了一类侧链型含氟磺化聚醚砜(s SPFES)与磺化聚酰亚胺(SPI)共混质子交换膜(s SPFES/SPI),研究了其吸水率、尺寸变化、质子电导率及稳定性等性能.结果表明,2种磺化聚合物以三乙胺盐型溶液共混及铸膜时相容性良好,制备的s SPFES/SPI共混质子交换膜结构均一,透明结实,离子交换容量为1.76~1.88 mmol/g.s SPFES/SPI共混质子交换膜表现出横向低于纵向的各向异性尺寸变化特性,在60℃水中横向尺寸变化率低于10%,经140℃加压水处理24 h后仍能保持较好的机械强度,质量损失低于6.1%.当温度高于50℃时,完全水合状态下的s SPFES/SPI共混质子交换膜的质子电导率均达到0.1 S/cm.
A series of blend membranes from a side-chain type fluorine-containing sulfonated poly( ether sulfone) s( s SPFES) and sulfonated polyimide( SPI) was prepared and characterized. The two sulfonated copolymers showed good compatibility in their trimethylamine salt form,producing uniform,transparent and ductile blend membranes during solution blending and casting processes. The resulting s SPFES / SPI blend membranes with ion exchange capacities in the range of 1. 76—1. 88 mmol / g showed some property differences in the water uptakes,size changes,proton conductivity and hydrolytic stability with the un-modified ones.Especially,their swelling behavior was considerable effected by the composition with obvious larger size changes in the membrane out-of-plane direction than the in-plane direction,exhibiting size changes no more than 10% in in-plane direction at 60 ℃ in water. The blend membranes could maintain rather good mechanical toughness after aging in water at 140 ℃ for 24 h with mass loss less than 6. 1%. For the fully hydrated blend membranes,their proton conductivity all reached 0. 1 S / cm at temperature above 50 ℃.