基于溶剂化作用对含芴聚芳醚砜膜的设计和构效关系研究

The pervaporation performance is mostly determined by solution and diffusion. In research process, the status of certain permeating component in the membrane matrix is usually deemed to be identical. However, just like water in Cell being classified as free water and bounded water, the permeating component should be further classified to reflect the real states in the membrane. In this project, Fluorene-containing poly (aryl ether sulfone) with different block ratios will be synthesized and prepared into membranes. The permeating components including Methanol and MTBE are further classified as “free component” and “bounded component” based on solvation action. We will investigate the effect of the quantity of function group and the membrane structure on the ratio of “free component”. The relationship between the ratio of “free component” and the separation performance will also be studied. The microcosmic behaviors are to be simulated by molecular simulating software. The solution and diffusion behaviors of permeating component on molecular level will be gained to testify the.experimental data. The comprehensive studying through the project can provide more accurate instruction for developing and optimization of pervaporation membrane.

渗透汽化膜的性能主要取决于溶解和扩散两个步骤，在研究过程中常把溶解在膜内某一渗透组分的存在状态视为相同的。然而，正如细胞中水分包括自由水和结合水，对渗透组分分类才能更准确地反映其在膜内的真实情况。本项目拟设计合成不同嵌段比例的含芴聚芳醚砜聚合物并制备成膜，基于溶剂化作用模型将溶解在膜内的渗透组分（甲醇和甲基叔丁基醚）分别进一步划分为“自由组分”和“结合组分”，研究官能团数量和高分子链构型对吸附饱和膜内“自由组分”比例的影响，并探明“自由组分”比例和膜对甲醇/甲基叔丁基醚混合物分离性能之间的规律，最后应用分子模拟软件模拟上述体系的微观运动行为，从分子尺度上获得渗透组分在膜内的溶解和扩散行为，为实验值提供计算依据。通过对该项目的深入研究可为渗透汽化膜的开发和优化提供更准确的理论指导。

膜分离技术在水处理、清洁能源、节能减排等国家重大需求领域优势突出，已成为实现可持续发展战略的重要组成部分。其中，渗透汽化技术因其高效节能、环境友好、设备结构紧凑、操作简便安全等优势应用广泛且前景诱人，高效分离膜的精密构筑及其传质机理研究将进一步推动传质分离领域的理论创新和实际运用，具有重要的科学意义和应用价值。本课题设计合成了不同嵌段比例的含芴聚芳醚砜聚合物并制备成膜用于甲醇/甲基叔丁基醚混合体系的分离，通过实验手段探明了官能团数量和高分子链构型对膜内渗透物吸附和扩散行为的影响规律，同时采用分子模拟手段构建了高分子膜模型，考察了渗透物分子在高分子相内的吸附和扩散行为，进而揭示了分离性能提升的机理，为实验数据提供计算依据。实验研究和理论计算结果表明，通过嵌段比例调控可以有效调变含芴聚芳醚砜膜内的自由体积参数和传质空间截面性质，膜的分离性能得到较大提高。另外，基于该项目制备的高分子材料，在其中引入功能化修饰的MIL-53(Al)-SO3H和氨基化氧化石墨烯进一步实现了物化性质和自由体积的调控，膜的分离性能得到进一步提高。该项目的研究成果将为渗透汽化膜的精密构筑和传质分离理论的完善起到较好的指导作用。