嵌段共聚物逐层自组装制备三维有序CO2纳米通道

CO2 separation and collection are concerning with the environment. CO2 separation membranes with high performance benefit the energy conservation and emission reduction. The CO2 separation membranes by block copolymers containing linear PEO have two main problems to be paid attention to. First, the crystallization tendency of the high molecular weight PEO limits the CO2 permeability. Second, low ordered phase structures would be formed without the use of external fields, leading the CO2 transport with low performance. Eliminating defects in the nanostructures, as well as the depressing PEO crystalization are the key factors to increase the CO2 permeability and selectivity. With the fact that well ordered structures can be fabricated on the patterned substrates, we proposed that applying the well ordered self assembled block copolymer surface as the substrate for a new turn self assembly of the block copolymer itself, would lead the successive nanostructure bearing the same order. 3D ordered nanostructures will be formed by repeating this process. Incorporating brush-like PEO with low glass transition temperature into the nanostructure, CO2 transport nanochannels through the entire membrane will be formed. In this way, the CO2 transport resistance can be lowered, and the CO2 separation membrane with high permeability and selectivtity will be obtained. The relationship between structures, including chemical structures and self assembly structures, and CO2 separation properties will be researched. The proposal also helps us to understand the self assemble phenomenon in nature.

CO2的分离和回收是关系环境的重大问题，制备高效CO2分离膜能够促进节能减排目标的实现。含线性PEO的嵌段共聚物作为CO2分离膜，须克服两大问题：PEO分子量大时结晶倾向严重，不利于CO2的分离；没有外场的调控，嵌段共聚物自组装形成多畴、无序的相结构，CO2在无序结构中的扩散阻力大，分离效果受到影响。消除缺陷，形成长程有序的纳米结构，并且抑制PEO的结晶是提高CO2通量和选择性的关键。嵌段共聚物在图案化基底上形成与之周期匹配的有序结构，利用嵌段共聚物自身形成的有序结构作为模板，再进行新一轮的自组装得到相同周期的有序结构，周而复始，实现有序结构在三维方向的延伸。将低玻璃化转变温度的梳型PEO引入到有序结构中，使其形成前后贯通的CO2纳米通道，得到高通量、高选择性的CO2分离膜。探索化学结构和自组装结构对CO2气体分离的影响规律，并为理解自然界中更为复杂的自组装现象提供思路。

CO2 的分离和回收是关系环境的重大问题。在本项目中，我们设计合成了含梳型PEO的嵌段共聚物，制备了自支撑的自组装薄膜，并对其进行了CO2性能的测试，得到了性能优越的CO2分离膜。线性PEO 分子量大时结晶倾向严重，不利于CO2 的分离。因此，抑制PEO 的结晶是提高CO2 通量和选择性的关键。将低玻璃化转变温度的梳型PEO 引入嵌段共聚物中，利用自组装，使其形成前后贯通的CO2 纳米通道，得到高通量、高选择性的CO2 分离膜。完成了计划书中的研究内容。.同时，我们对研究计划进行了一些必要的、深入的拓展。我们对梳型PEO的共聚物进行了锂离子掺杂，研究了电导性能，探索其在锂离子传导膜方面的应用前景。我们还将具有CO2敏感的基团接枝聚合到纳米孔道表面，研究了纳米通道的离子传导的CO2响应特性，得到了快速CO2响应的流体二极管。利用嵌段共聚物自组装构建了环境响应的界面，表面的纳米结构与环境响应基团的协调作用效果，实现了智能响应的界面。