| Porous organic polymers are a new type of porous materials that have emerged in recent decades.Compared with inorganic porous materials?e.g.molecular sieves?and organic-inorganic hybrid porous materials?e.g.MOFs materials?,porous organic polymers not only have high porosity but also have the characteristics of low skeleton density,designable structure,functionalization of skeleton and high stability.These characteristics make porous organic polymers have more extensive application value,and attracted much attention in the field of material science.Porous organic polymers mainly include Hyper-Cross-linked Polymers?HCPs?,Polymers of Intrinsic Microporous?PIMs?,Covalent Organic Frameworks?COFs?,Conjugated Microporous Polymers?CMPs?,Porous Aromatic Frameworks?PAFs?,covalent triazine frameworks?CTFs?and other categories.Among many porous materials,Hyper-Cross-linked Polymers?HCPs?and Covalent Organic Frameworks,COFs)are two kinds of organic porous materials that have attracted great interest of researchers due to their unique structural characteristics and rich structural forms.HCPs and COFs materials due to their flexibility and richness in ligand selection the structural characteristics of high porosity and large specific surface area exhibited by traditional porous materials.Hypercrosslinked polymers?HCPs?are mainly organic porous polymers prepared by Friedel-Crafts alkylation reaction.Due to the high degree of crosslinking of the super-crosslinked polymer,the obtained polymer has a high degree of rigidity,which prevents the polymer chains from being tightly stacked,and thus there are some pores between the molecular chains of the polymer.The rigidity of the super-crosslinked polymer enables the material to have higher stability,higher specific surface area and micropore volume.After decades of development,monomers with different structural properties have been increasing and the properties of polymers have also been significantly improved.Compared with HCPs material,COFs material is a porous material with ordered structure connected by pure organic molecules through covalent bonds.Due to the reversibility of polymerization reaction,the formation of COFs crystal can be controlled by thermodynamics.Since all the components are organic,they are also called"organic molecular sieves".This thesis mainly focuses on the design,synthesis and characterization of the above two new porous materials and their applications in adsorption separation and energy storage.The first part is mainly about HCPs materials.At present,most of the HCPs materials are used in the field of gas separation including the separation of olefins and alkanes,or the separation of liquid phase mixtures,such as aromatic hydrocarbon liquid phase separation membranes in petrochemical industry.There are few reports on the separation of organic vapors,and the performance is quite different from the former two.Based on this,we have designed a new super-crosslinked polymer HCPs.The performance of the material in the fields of adsorption and selective separation was also studied.the research results mainly include the synthesis and characterization of P-?S?-1 material.P-?S?-1 is a small organic molecule with carbazole functional group and HCPs material with large specific surface area and microporous?d<2nm?structure was obtained by catalytic polymerization with ferric chloride.The test results show that the material has good adsorption performance for some VOCs?Volatile organic compounds?,such as p-xylene,o-dichlorobenzene and carbon disulfide.It also utilizes the unique conjugated aromatic property of HCPs material,and has certain application value for selective adsorption of benzene and cyclohexane,two organic vapors,in industrial production and post-treatment.In the second part,we explored the potential application of COFs materials in adsorption separation field.As a new type of pure organic porous material,COFs material has two basic structural forms,two-dimensional and three-dimensional.The two-dimensional COF material has a lamellar structure similar to graphene,and the lamellar structure also contains uniformly distributed pores with basically the same size.When the lamellar structures are stacked together,vertically distributed pore structures can be formed.The existence of these structures endows the two-dimensional COF material with unique properties.Based on these characteristics of two-dimensional COF material,we further modified and modified it for the adsorption and separation of ethylene and ethane gas.Based on the material characteristics of COFs,COF-316material with excellent thermal stability was designed and prepared.cuprous iodide molecules were dispersed into the pores of COF-316 by vacuum heating.after characterization and testing,cuprous iodide monodisperse COF-316-Cu I material was obtained.further,through static adsorption test,it was found that this new material has different adsorption capacity for ethylene ethane gas.IAST theoretical analysis and calculation are carried out on the obtained adsorption data,and it is found that the adsorption and separation ratio of the material to ethylene components in ethylene ethane mixed gas with the same proportion can reach between 4 and 5 at normal temperature and normal pressure.The third part is mainly about the design and synthesis of SATD-Me-COF material with methyl group in the pore canal.Halogen is added into the pore canal of COFs through chemical modification and functionalization.Imidazole-based ionic liquid is added into the pore canal of SATD-Me-COF through vacuum evaporation.SATD-Me[Im I]Br material is finally prepared.Through gas adsorption test,it is found that after the above two functional methods,COFs material with certain selective adsorption of carbon dioxide and methane molecules is formed in the pore canal of the material.In the fourth part,the main work is to design a COFs material with sulfonate groups in the synthetic channels:SA-DABS-COF.the monomer used in this material is easier and more efficient to synthesize,and the cost is lower.further research is carried out on the proton transport performance of the porous material with sulfonate groups.the proton transport performance of the SA-DABS-COF material is tested under anhydrous conditions.it is found that the proton transport performance of the material is low,and after the temperature exceeds 100 degrees celsius,the performance drops sharply,and proton cannot be stably transported.In order to improve this defect,nitrogen-rich heterocyclic small molecule 1,2,4-triazole is dispersed into the pore canal of SA-DABS-COF by vacuum self-diffusion,and SA-DABS-TA is obtained.Through nitrogen adsorption analysis,it can be found that the surface area of SA-DABS-TA is lower than that of untreated SA-DABS-COF.Through the same method and conditions as SA-DABS-COF to test the proton transmission performance of SA-DABS-TA under anhydrous conditions,it is found that the proton transmission capability of the material is improved at medium and low temperatures,and it is also found that proton transmission can still be realized in the temperature range over 100?,and finally it is found that the material can work stably at 160?.At this time,the highest anhydrous proton conductivity can reach 8.1×10-4 S?cm-1.In order to further explore the possible transmission mechanism of the material,the activation energy of SA-DABS-COF is 0.26 e V through theoretical calculation,which satisfies the mechanism of proton jump transmission.The calculation of activation energy for SA-DABS-TA shows that the material has different activation energy values at different temperatures.However,all of them are less than 0.4 e V,and the interior of the surface material still belongs to proton jump mechanism.This paper speculates that the formation of hydrogen bond network different from SA-DABS-COF may result in such difference.Through the synthesis and exploration of triazole functionalized COFs materials,it is found that the temperature range of proton transport can be increased by adding heterocyclic molecules to the materials,thus expanding the development ideas of proton transport materials. |
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