基于多元胺纳米粒子组装纳滤膜的构筑及其耐污染机制研究

Exploring efficiency and controllable methods for fabrication of membrane materials and nanofiltration membranes with high perm-selectivity, good stability and antifouling properties is the hot and key research topic in this field. A novel strategy of “surface self-assembling-interfacial crosslinking” for rapidly constructing nano-based polyamide composite membranes is proposed in this project. Design and synthesis of different types of amine monomers, then they were copolymerized with biomimetic binding agent dopamine and self-assembled into amine nanoparticles (SANPs). Subsequently, SANPs-based composite membranes were prepared via surface self-assembling and interfacial crosslinking method on a porous supporting membrane. The regulation of SANPs structure, particle size and membrane preparation conditions on the microstructure and surface properties of composite membranes were investigated. Study on the nanofiltration performance of SANPs-based composite membranes in aqueous/ organic solutions, and the evolution of membrane pore structure and surface characteristics during service process. The relationship between the SANPs structure, the membrane structure and performance was studied, and the high permeability and selectivity principle, and the antifouling mechanism of nano-based composite membranes were probed. The research of this project has developed a new type of nanomaterials and their nano-based composite membranes could be fabricated with a facile and controllable method, providing a new route to design high performance nanofiltration membranes, and is of important scientific significance and application prospect.

探索高效可控的纳滤膜材料及其成膜方法，开发具有高渗透选择性和耐污染稳定性的纳滤膜是当前纳滤分离领域的研究热点和关键问题。本项目提出“表面组装—界面交联”快速构筑聚酰胺纳米复合膜的新策略。设计、合成不同类型多元胺单体分子，以多巴胺为仿生粘合剂，在水溶液中聚合组装形成多元胺纳米粒子材料，通过调控纳米粒子在多孔支撑膜表面的组装行为和界面交联过程，制备聚酰胺纳米复合膜。探索多元胺纳米粒子结构、尺寸和制膜工艺对复合膜微观结构和表面性质的调变规律；研究纳米复合膜在水/有机溶剂体系中的纳滤分离性能，以及在服役过程中膜孔结构和表面性质的演变情况；建立多元胺纳米粒子、组装膜结构和性能间的内在关系，揭示纳米复合膜的高渗透选择性机理和耐污染机制。本项目的研究开发了一种新型成膜纳米材料及其简便、可控制备纳米复合膜的方法，为高性能纳滤膜的研制提供新思路，具有重要的科学意义和应用前景。

纳滤膜分离作为一种新型、节能、环保的技术，在饮用水净化、废水处理、化工物质分离、资源回收等领域中扮演着越来越重要的角色。探索高效可控的纳滤膜材料及其成膜方法，开发具有高渗透选择性和耐污染稳定性的纳滤膜是当前纳滤分离领域的研究热点和关键问题。本项目从膜材料和制膜方法入手，建立了“表面组装—界面交联”快速构筑聚酰胺纳米复合膜的新方法。遴选、设计不同多元胺单体分子，以多巴胺为仿生粘合剂，在水溶液中通过氧化聚合制备了多元胺纳米粒子；通过调控多元胺纳米粒子的亲/疏水性、荷电性、内部孔洞结构，粒径大小，优化成膜工艺条件，制备了系列多元胺纳米基元膜。深入研究了多元胺纳米粒子的物化性质及其在多孔支撑膜表面的组装行为对所得纳米基元膜微观结构和表面性质的调变规律。详细考察了不同类型多元胺纳米基元膜对水溶液/有机溶剂体系中不同价态无机盐/有机物分子的分离性能。进一步以两性多元胺纳米粒子为模板诱导界面晶化构筑了超高渗透选择性聚合物纳米基元膜，结合低场核磁、液态原子力、正电子湮灭技术，以及分子动力学模拟方法分析了纳米基元膜的微观结构和传质行为，揭示了聚合物纳米基元膜高渗透选择性机理。另外，通过芳香胺纳米基元诱导银纳米粒子在膜表面原位生长，制备了有机-无机复合纳米分离膜，针对不同类型的污染物如有机微污染物、蛋白质、细菌等，进行了耐污染抗菌性能的研究，建立了纳米基元材料结构～膜结构～膜性能之间的构效关系，更深入地探索了纳米基元膜耐污染抗菌机制。本项目的研究开发了新型成膜纳米材料及其简便、可控制备纳米基元膜的方法，为构筑高性能纳滤膜奠定了研究基础，具有重要的科学意义和潜在应用价值。