优先透丁醇渗透汽化膜的绿色制备及成膜机制

The key technology of bio-butanol separation is how to obtain high performance of pervaporation with low cost. The traditional pervaporation membrane preparation based on organic solvent evaporation technique cause environmental pollution and high membrane cost. The key scientific problems on study of bio-butanol permselective pervaporation membrane are the green membrane preparation and its membrane formation mechanism. In this program, PDMS pervaporation membrane will be prepared using water as solvent, and how to control its membrane structure will also be studied. The essence of squeezing and integrating between latex particles will be revealed. The dense membrane formation model based on bridging and squeezing between latex particles will also be set up. Coordination and competition among Polymer/water/surfactant/crosslinker which cause evolution and change of membrane structure will be investigated. The boundary condition of membrane changed from pore structure into dense structure will also be investigated. Inner relationship between micro-structure and macro-performance of PDMS pervaporation membrane will be mined. The relationship between structure and performance of pervaporation membrane will be revealed. The results will provide theoretical guidance for design and preparation of green pervaporation membrane with high performance for bio-butanol separation.

如何得到高效低成本的渗透汽化分离新技术，是生物丁醇分离研究中要解决的关键技术之一。传统基于有机溶剂挥发的膜制备方法，造成环境污染、安全生产问题和膜成本的增加；构建绿色膜制备路线和揭示其成膜机制，是优先透丁醇渗透汽化膜研究的关键科学问题。本项目研究一种新型以水为溶剂聚二甲基硅氧烷（PDMS）渗透汽化膜的绿色制备路线设计与膜结构调控新方法。揭示绿色致密膜形成过程中乳胶粒之间挤压与融并作用的本质特征，构建基于乳胶粒间架桥与碰撞挤压作用的致密膜形成新模型。研究聚合物/水/表面活性剂/交联剂之间相互协调与竞争所引起膜结构的演变与突变过程，探寻引起膜结构由有孔向无孔转变的边界条件。挖掘PDMS渗透汽化膜的微观结构与宏观分离性能之间的内在本质联系；揭示渗透汽化膜的构效关系。为高性能优先透丁醇渗透汽化膜的绿色制备和路线设计提供理论指导。

本项目研究了一种以水为溶剂聚二甲基硅氧烷（PDMS）渗透汽化膜的绿色制备路线设计与膜结构调控新方法。揭示了致密膜形成过程乳胶粒之间挤压融并作用的本质特征，构建了基于乳胶粒间架桥与碰撞挤压作用的致密膜成膜模型。研究了不同表面活性剂体系绿色制备的PDMS渗透汽化膜；通过向水乳液铸膜液体系中引入乙烯基三乙氧基硅烷（VTES），构建了水/VTES/PDMS铸膜液体系，制备了疏水性增强的PDMS渗透汽化膜；探究了渗透汽化膜底膜的成膜规律其对复合膜的表界面作用；研究了渗透汽化复合膜的成膜规律及高分子链段构象的变化规律；考察了成膜温度和成膜过程中交联剂的用量与渗透汽化复合膜分离性能之间的关系；研究了以水为溶剂制备的渗透汽化膜分离性能提高的机理；探究了温度、二月桂酸二丁基锡、水和乙醇等对PDMS交联、固化过程的影响。