Synthesis of highly porous monolithic materials with well-defined multimodal pore radii distribution

在分离科学、隔热、吸附剂等许多技术应用中，多孔材料起着至关重要的作用。这种多孔材料的孔径分布、网络的扭曲度和表面性质在很大程度上影响与有机底物、溶剂分子等的相互作用，例如用于多孔介质中药物的不良结晶。近年来，在多孔材料的合成中出现了许多新的合成方法，如基于模板机制、故意烧结工艺等，但合理设计特定的孔隙结构仍然相当困难。特别是在一锅合成中同时设计化学成分、孔结构和宏观形貌的特定应用仍然是一项艰巨的任务。在本项目的前两年，通过相分离策略和高内相乳剂的结合，制备了具有三模态孔径分布的硅胶单体。此外，从乙醇化铝前驱体开始，可以制备介孔/大孔氧化铝单体。在本项目中，这些任务将得到进一步发展。本项目拟从精心设计前体分子（多元醇改性硅烷、乙醇酸铝等）出发，结合模板方法（相分离、高内相乳液），合成具有多模态孔隙结构和可变化学成分（SiO2、Al2O3和MgO）的整体凝胶。

For many technical applications, e.g. separation science, heat insulation, as adsorbents, etc., porous materials play a vital role. The pore size distribution, tortuosity of the network and the surface properties of such a porous material influence to a large extent the interaction with organic substrates, solvent molecules, etc., as it is e.g. described for the undesirable crystallization of pharmaceutical drugs in porous media. In the last years, many novel synthetic approaches have been developed in the synthesis of porous materials, e.g. based on templating mechanisms, deliberate sintering processes, etc., but it nevertheless remains quite difficult to rationally design specific pore structures. Especially the simultaneous design of chemical composition, pore structure and macroscopic morphology for specific applications in a one-pot synthesis remains a difficult task. In the first two years of this project, silica monoliths with, i.e. trimodal pore size distribution, have been prepared via a combination of phase-separation strategies and high-internal phase emulsions. In addition, meso/macroporous alumina monoliths could be prepared starting from glycolated aluminum precursors. In the present project, these tasks will be further developed. Starting from deliberately designed precursor molecules (polyol-modified silanes, aluminum glycolate, etc.) and a combination of templating approaches (phase separation, high internal phase emulsions), it is planned to synthesize monolithic gels with a multimodal pore structure and variable chemical composition (SiO2, Al2O3 and MgO) in this project.