Design And Synthesis Of Porous Organic Polymers For Heterogeneous Catalysis

The continuous development of the industrial society has spawned many energy and environmental problems,which are urgently needed to be solved.The research and development of green chemistry has become a top priority.The search for highly selective and active catalysts,especially those that are easy to recycle,is critical to the development of sustainable chemical processes.The selective oxidation of alcohols is a fundamental shift in organic synthesis and industrial chemistry.The system with 2,2,6,6-tetramethylpiperidine-1-oxyl radical(TEMPO)as catalyst and O₂ as oxidant is easy to obtain,environmentally friendly,high catalytic efficiency and good chemical selectivity,which makes it a very attractive method.However,the recycling of catalysts has always limited its application in industrial production.On the other hand,photocatalysis technology is considered to be a promising technology for converting solar energy into complete hydrogen energy.Its economic,clean,safe and renewable characteristics have been widely concerned by countries all over the world,but the photocatalytic performance of the known photocatalysts is far from being used for commercial applications,especially in solar energy conversion fuels.Therefore,this paper is devoted to the design and synthesis of new functionalized porous organic polymers with certain catalytic properties.Part one,we use TEMPO group as one part of the reaction monomer to directly participate in the polymerization reaction.We successfully constructed four kinds of free-radical polycarbazole conjugated microporous polymers with different linking groups through one-step high-efficiency oxidative polymerization.Then,they were characterized by material structure and morphology.These free radical-containing polymers have high specific surface area,stable chemical and thermal stability,and they exhibit good stability and catalytic performance for aerobic selective oxidation of alcohol.It can be recycled at least 20 times.This environmentally friendly condition meets the requirements of green chemistry and is suitable for a wide range of alcohols.Part two,a heptazine monomer with an aldehyde substitution was designed and synthesized,we have successfully prepared three nitrogen-rich covalent organic polymers by Schiff base reaction.These polymers all have a single nanopore and a relatively stable framework structure.The analysis of their optical band gaps shows that they may have potential application value in the field of visible light photolysis and hydrogen production.