中文摘要：

以2种二酐、2种二胺为单体，制备了4种不同结构的聚酰亚胺（PI）均质膜；用建立的动态吸附／脱附实验装置测定水蒸气在PI膜中的吸附／脱附行为；考察了不同结构的PI膜对水蒸气吸附／脱附的影响；计算了反常扩散指数；研究了温度对水蒸气在聚酰亚胺膜（PI）中扩散系数的影响．分析了扩散系数与温度和聚合物重复单元的摩尔自由体积之间的关系．研究结果表明：水蒸气小分子在PI膜中的扩散系数随着温度增加而增加，随着聚合物重复单元摩尔自由体积的增加．扩散系数也呈上升的趋势．

英文摘要：

Four kinds of different structures of homogeneous polyimide （PI） membranes were prepared by two kinds of dianhydrides and two kinds of diamines. A set of dynamical sorption/desorption equipment on - line was used to determine the sorption/desorption behaviors of steam in polyimide membranes. The diffusion of steam in PI membranes was studied under different temperatures. The diffusion coefficients and anomalous dif- fusion factors were calculated. The relation between diffusion coefficients of steam and the repeat unit molar free volume of PI was found from the diffusion coefficients. It can be concluded that the diffusion coefficients of steam in PI membranes increase with temperature increasing and the diffusion coefficients of steam in PI increase with the repeat unit molar free volume of PI growing.