| Conjugated microporous polymers,as a novel micro-nanoporous material,are widely used in the separation,adsorption,sewage treatment,energy storage,gas storage and catalysis due to their high specific surface area,excellent chemical properties,thermal stability and adjustable pore properties.In this paper,four novel thienyl conjugated microporous polymers were prepared by Pd(0)/Cu I catalyzed Sonogashira-Hagihara cross-coupling polycondensation reaction of 2,3,5-tribromothiophene and 2,4-dibromothiophene with 1,3,5-triacetylbenzene and 1,4-diethynylbenzene.The resulting polymers were applied to adsorption of volatile iodine and the capture of dissolved iodine from organic solvents.Our works provide the basic data for conjugated microporous polymer in the capture and remove of radioactive iodine in the nuclear industry.In the second chapter,four monomers(2,3,5-tribromothiophene,2,4-dibromothiophene,1,3,5-triacetylbenzene and 1,4-diethynylbenzene)were used to synthesize the SCMP-1~SCMP-4 through Pd(0)/Cu I catalyzed typical Sonogashira-Hagihara reaction.In the synthesis processes,DMF and triethylamine as the reaction solvent.13 C solid nuclear magnetic spectroscopy(NMR),Fourier transform infrared spectroscopy(FTIR)and elemental ana lyzer were measured to confirm the structure and chemical composition of the resulting polymers.Thermogravimetric analysis shows that the thermal decomposition temperature exceeded 300 ?.The morphology of the materials was characterized by SEM.O ur polymers were mesoporous materials proved by nitrogen adsorption and desorption experiment.In the third chapter,the four kinds of thienyl conjugated microporous polymers were used as adsorbents to study the adsorption and removal properties of porous materials in volatile gaseous iodine and dissolved iodine in organic solvents,and the cyclic adsorption properties of the polymers were studied deeply after iodine adsorption.The results showed that SCMP-2 has the highest adsorption value for volatile gaseous iodine,and its adsorption capacity reached 222 wt%.By analyzing the adsorption data,it was found that the adsorption value were affected by the microscopic properties of the polymer.An other factor was that the polymer contains some kind of electron-rich groups,it can significantly increase the affinity of the polymer and the gaseous iodine molecules to increase the adsorption value.In the adsorption experiments of dissolved iodine in organic solvents,SCMP-2 still has the highest adsorption capacity,when the initial solution concentration is increased,the adsorption driving force of the whole solution system was significantly improved.The polymer samples were analyzed by XPS after adsorption of iodine.The results found that the molecular state of iodine is present in the polymer,indicating that the adsorption process between conjugated microporous polymer and iodine is mainly physical adsorption.After three cycles of adsorption,the adsorption capacity of SCMP-2 was up to 161.94 wt% and the cycle percentage was 87%.In the fourth chapter,four kinds of thienyl conjugated microporous polymers were used as adsorbent materials to explore the kinetics and thermodynamics adsorption properties of iodine in organic solvents.The results show that the quasi-second-order kinetics model has the highest linearity and is better explain ation the adsorption kinetics process in the four kinetic models.The whole adsorption process corresponds to three control velocities at the same temperature,but the whole adsorption rate is mainly determined by the moving speed of iodine molecules in the liquid film and the diffusion rate.In the two thermodynamic models,the R2 value of Langmuir adsorption isothermal model is more than 0.99,which is more consistent with the thermodynamic adsorption process of iodine in the organic solution.In the analysis of the separation factor,it was found that the R L value of each sample were between 0 and 1,indicating that the adsorption was favorable.The simulated data of the Gibbs free energy equation on the adsorption process show that the increase of temperature is beneficial to the whole adsorption process,which is spontaneous irreversible process. |
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