Synthese And Applications Of Organic Porous Polymers Based On Thiophene Coupling

In the past decade,people have paid more and more attention to porous materials.The research and development in this field is also very rapid.From the initial inorganic natural porous zeolite to the subsequent molecular sieve,then,people found inorganic-organic hybrid materials,such as metal-organic framework porous polymers(MOFs).Then porous organic polymers was used.Organic porous polymers are mostly composed of functional units with backbone units.The backbone units are bonded by covalent bonds to form a highly cross-linked structure that renders them insoluble in common solvents.In addition,the organic porous material obtained by covalent bonding has better thermal stability and chemical stability.The high specific surface area of porous materials allows it to be used in many applications,such as organic catalysis,gas adsorption and separation and fluorescence detection and so on.In this paper,2,4,6-(trithien-2-yl)aniline and 2,6-(dithiophen-2yl)aniline,1,3,5-tris{1-[3,5-bis(thiophene-2-yl)phenyl]-1H-1,2,3-triazol-4-yl}benzene were chosen as core skeleton structure unit.Under the action of ferric chloride,thiophene was oxidized and coupled to synthesize porous organic polymers PTPA and PTPTB,which were used to support gold nanoparticles and applied to heterogeneously reduction of p-nitrophenol(4-NP).Organic porous polymers of PTPTB can also be used for the detection of nitroaromatics.First of all,by adjusting the ratio of 2,4,6-(trithiophene-2yl)aniline and 2,6-(dithiophene-2yl)aniline,three porous polymers were obtained by oxidative coupling of thiophene.The corresponding catalysts Au/PTPA-1,Au/PTPA-2 and Au/PTPA-3 were prepared by in situ reduction of HAuCl4 by NaBH4.NaBH4 is used as reducing agent in aqueous solution,and the catalysts were used to catalyze the reduction of p-nitrophenol and methylene blue.The catalyst Au/PTPA-1 can be recycled six times in the reduction of p-nitrophenol without significant reduction in catalytic effect.Then the catalyst Au/PTPA-1 was chosed to catalyze the reduction of Congo Red.Secondly,the structure of the previous chapter was improved by introducing a trivalent electron-pair triazole into the monomer through the click reaction of the terminal alkyne and azide.1,3,5-tris?1-[3,5-di(thiophen-2-yl)phenyl]-1H-1,2,3-triazol-4-yl?benzene was selected as a skeleton structure unit,oxidative coupling of thiophene under the condition of ferric chloride as an oxidant produced the target polymer.On the one hand,it was evenly dispersed in DMF for preparing the probe,and then ultraviolet fluorescence was used to detect the nitroaromatic compound.On the other hand,using the obtained organic porous polymer as a template,NaBH4 was used as a reducing agent to prepare catalysts for supporting Au nanoparticles.The resulting catalyst was used to catalyze the reduction of 4-nitrophenol.Thirdly,the molecular structure was identified by IR,1H NMR and 13C NMR.The thermal stability,morphology and distribution of nanoparticles were determined by TG,SEM and TEM,respectively;calculate the specific surface area and pore volume of the porous material by testing the N2 adsorption-desorption curve of the polymer the tests showed that the prepared catalysts have good thermal stability.The metal loadings were determined by ICP-AES.Using XRD and XPS to determine the metal valence.The progress of the reaction was monitored using UV-Vis and fluorescence spectroscopy.In summary,in this paper,two kinds of organic porous polymers have been successfully prepared by catalyzing thiophene oxidative coupling with ferric chloride as catalyst,and both have good thermal stability.Through the improvement of the monomer,the specific surface area of the polymer has increased.Both the catalysis and the detection of nitroaniline have achieved good results.