Synthesis And Properties Of Enol-keto Interchange COFs

Covalent organic framework(COFs)is a kind of porous crystalline polymer material composed of C,H,O,N,B and other elements,which forms periodic network structure through reversible covalent bonding of organic building units.It has potential application prospects in gas adsorption and separation,energy storage,catalysis,biomedicine and other fields because of the regular pores,high specific surface area,good crystallinity,excellent chemical stability and modified pore structure,In this paper,several novel COFs was designed and synthesized.We explored the COFs properties which related applications.COFs were characterized by PXRD,FT-IR,SEM and TGA,which indicated that the material was successfully synthesized.According to the COFs different properties to study,we explored the COFs various functional applications.The main research contents of this paper are as follows:In chapter 1,The basic situation of COFs material was introduced;According to the different covalent bonds and development history of COFs,it was classified and introduced.COFs materials with stimulus response properties were summarized,including some physical and chemical stimuli.The application of COFs materials in separation,including gas separation and liquid separation was summarized.In chapter 2,SPI-AN-COF with enol-ketone tautomorphic structure modified by spiropyran functional group(SPI-AN)was successfully constructed by traditional solvothermal method through bottom-up synthesis strategy..First,SPI-AN was studied,which showed good light response and acid-base response characteristics,and good recyclability.Then,SPI-AN-COF was studied.SPI-AN-COF has good crystallinity and stability,and also shows structural transformation to light stimulation and acid-base stimulation,so the SPI-AN-COF shows good stimulus response.In chapter 3,Two new COFs with microporous structures were successfully synthesized by using 4,4-diamino-2,6-dimethylbiphenyl as building units.Both COFs showed good crystallinity,thermal stability and chemical stability.Considering its unique microporous properties,it had been applied in gas adsorption applications of n-pentane and isopentane.These two COFs showed different hydrophilicity,so they are used in oil-water separation experiments.The results show that the two kinds of COFs have good gas adsorption performance and oil-water separation ability.In chapter 4,the content of this paper was summarized,and the development of covalent organic framework(COFs)materials was prospected.