摘要
以2种二酐,3种二胺为单体,两步法制备了6种不同结构的聚酰亚胺均质膜.通过红外光谱和元素分析证实了其重复单元的分子结构,测定了这几种膜的物理性质和对水蒸气的动态吸附性能,并计算出其反常扩散指数dw.实验表明,随着聚合物二胺单元分子结构的变化,按MDA、ODA、PDA的顺序,密度逐渐变大,链间距逐渐减小,链堆砌变得紧密,水蒸气在膜中的吸附和扩散也变慢,并出现从正常扩散到反常扩散的过渡现象.
Six kinds of homogeneous polyimide membranes were prepared by two kinds of dianhydrides and three kinds of diamines in a twostep way.The chemical structures of repeating units of polymers were conformed by their infrared spectrum and element analysis.The physical property and vapor sorption behavior in membranes were investigated,and anomalous diffusion factors were calculated.It was found that as molecular structure of diamine fragments varied in the order of MDA,ODA and PDA,their density became larger,dspacing became smaller and chain packing became denser.The vapor sorption and diffusion behaviors in membranes decreased in the same order,and the transition from Fick diffusion to anomalous diffusion appeared.
出处
《膜科学与技术》
CAS
CSCD
北大核心
2003年第5期5-9,14,共6页
Membrane Science and Technology
基金
国家自然科学基金资助项目(20076023
20276034)
关键词
聚酰亚胺
渗透汽化膜
制备
结构
动态吸附特性
反常扩散
polyimide
homogeneous membrane
membrane structure
dynamic sorption
anomalous diffusion
