聚合物膜制备过程中的相关基础问题 |
作者:任吉中 邓麦村 |
单位: 中国科学院大连化学物理研究所 |
关键词: 聚合物膜;膜结构;大空腔;厚度梯度膜;流变 |
DOI号: |
分类号: TQ028.8 |
出版年,卷(期):页码: 2011,31(3):39-46 |
摘要: |
本文综述了聚合物膜制备过程中的相关基础问题和取得的研究进展.通过铸膜液邻近比和凝胶邻近比描述制膜体系的热力学状态和凝胶特性,借助于延迟相分离时间与凝胶时间来描述膜的形成过程.通过“粘性指进”来解释大孔腔的形成,从铸膜液邻近比和厚度梯度膜的概念上调控膜结构在指状孔与海绵状孔之间的转变.对于中空纤维和平板膜的制备来说,铸膜液的流变特性强烈影响着膜的结构与分离性能.通过Extreme 模型把孔径分布函数与截留分子量关联在一起,对表征膜的分离特性起到指导作用. |
Some basic research progress for the formation of polymeric membranes by immersion precipitation method is reviewed. The approaching ratio and the approaching coagulant ratio are used to describe the thermodynamic state of the casting solution and the precipitation property of the coagulant. The membrane formation process is described with two macroscopic time scales, delay time and gelation time, and “viscous fingering” is used to explain the formation of macrovoids. The transition of membrane morphology between sponge-like and sponge-like structure is reviewed by changing the approaching ratio and membrane thickness. For the preparation of flat sheet and hollow fiber membranes, the rheological characteristics of the dope solution strongly influence the membrane morphology and its performance. According to Extreme model, the pore size distribution parameters and molecular weight cut-off is coupled together, which is useful for the characterizing the membrane performance. |
基金项目: |
863基金项目(2008AA06Z325)和科技部国际合作项目(2009DFA61700)支持 |
作者简介: |
任吉中(1970-),男,河南新野人,博士,研究员,从事膜制备与膜分离过程研究.*通讯联系人(renjizhong@dicp.ac.cn) |
参考文献: |
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