响应性型Pickering乳化剂的界面行为及其在多相催化反应中的应用

Pickering emulsion catalysis is a new technology to strengthen the efficiency of multiphase reaction system, where its core is the solid particles with catalytic function groups as the emulsifier. The emulsion stability of multiphase reaction system will thus be increased and the reaction efficiency will be greatly improved by avoiding the interfacial transfer due to the enriched catalyst particles at the phase interfaces. However, in the process of the reaction, the change in the reaction system will reduce the interfacial stability of the catalyst, so as to reduce the efficiency of catalytic reaction. The key to solve this problem is Pickering emulsion structure and property of the catalyst interface control. This project will explore the solid particle grafted with solvent-responsive hybrid polymer brush to establish a tunable solid-liquid interface in accordance with the reaction, which can satisfy the Pickering emulsion catalyst concentration in the interface thermodynamic conditions. We aim at exploring the surface/interface mesoscale structure, its formation mechanism and its regulation by combining the experimental, theoretical and simulation methods. The surface/interface behaviors of the solvent-responsive Pickering emulsion catalyst and its control method will be studied to clarify the influence of the surface/interface structure on fluid solid particles, which will provide a new strategy for efficient catalyst design and theoretical guidance for multiphase reaction process.

Pickering乳化催化是一种强化多相反应体系效率的新技术，其核心是具有催化功能的固体颗粒作为乳化剂，富集于相界面的催化剂颗粒可以避免反应物的跨界面相际传递，提高反应效率。但反应进行过程中体系组成的变化会降低界面催化剂的界面稳定性，从而降低催化反应效率。解决这一问题的关键是Pickering乳化催化剂的表界面结构和性质的调控。本项目提出在固体颗粒表面铆接具有溶剂响应性的混合聚合物刷，达到固液界面的性质能够随反应进行自行调整，从而满足Pickering乳化催化剂能够富集于界面的界面热力学条件。项目拟采用实验与理论和分子模拟相结合的方法，研究多相体系表界面结构及其形成机理，探索溶剂响应型Pickering乳化催化剂的表界面行为及其调控方法，阐明表界面结构对流体介质中固体颗粒相互作用和动态团聚行为的影响规律，为高效界面催化剂的设计提供新思路，为多相反应过程强化提供理论指导。

Pickering界面乳化催化技术可通过颗粒催化乳化剂在界面上的富集，强化反应物两相界面的相际传递速率，从而提高反应效率。然而，随着反应的进行，产物的生成，体系中的组成会发生变化，从而影响颗粒催化乳化剂的界面稳定性，降低催化反应效率。针对这一问题，本项目提出了利用响应性Pickering乳化催化剂进行表界面结构和性质的调控，实现其在两相界面上的自适应调控，从而满足Pickering乳化催化剂能够富集于界面的界面热力学条件。本项目采用实验与计算机模拟相结合的方法，通过分子设计调控表界面结构，从而调控固体颗粒聚集结构，揭示表界面结构和性质、固体颗粒聚集体结构和性质形成的分子机理，探索不同影响因素的协同作用机制，阐明表界面结构对流体介质中固体颗粒相互作用和动态团聚行为的基本规律。具体研究内容包括：CO2响应性颗粒的催化-乳化性能的“协同与竞争效应”；Pickering颗粒催化乳化体系中传质与反应的竞争和动力学与热力学的竞争；聚合物乳化剂和金纳米球刷乳化剂的响应性乳化行为研究；两亲性Pickering颗粒乳化剂在界面的富集及其驱油中的应用。上述研究结果为高效界面催化剂的设计提供新思路，为多相反应过程强化提供理论指导。目前已在国际知名学术刊物上发表研究论文14篇，其中被SCI收录10篇；在国内外学术会议上交流论文3篇；申请发明专利2项。参加本项目主要研究工作的研究生中有1人获博士学位，5人获硕士学位。