Study On The Preparation Of Conjugated Microporous Polymers Membrane And Its Separation Properties

Conjugated microporous polymers（CMPs）are a unique class of porous organic polymers materials withπ-conjugated framework,adjustable micro-nanoporous structure and transformable surface wettability.It is widely used in the fields of catalysis,gas storage and organic contaminants separation/adsorption.However,most CMPs materials are amorphous and powdery and have poor processability,which greatly limits their practical applications.Based on this,this thesis prepares CMPs membrane materials by template method and interfacial polymerization method,intends to solve the difficult processability problem,and systematically studies its use in wastewater treatment containing organic contaminants,particulate matter（PM）capture and volatile organic compounds（VOCs）vapor adsorption.It provides a research idea for the preparation of 2D CMPs with separation functional materials and its application.The main research contents include:（1）Firstly,using 1,3,5-triacetylenebenzene and 1,4-dibromobenzene as monomers,and anodized aluminum oxide（AAO）film as hard template,two CMPs were prepared by polymerization.Membrane material.According studies,it has found that the monomer concentration and template immersion time have a greater impact on the microscopic morphology of the CMPs film.When the monomer concentration was less than 0.02 mmol m L^-1,a complete CMPs film did not form.When the monomer concentration was 0.05 mmol m L^-1 and the template immersion time was 10-20 min,the CMPs film of nanotubes did not obtain after the template was removed;when the immersion time was 60 min,a nanorod-like CMPs film could be obtained finally.Based on the lipophilic and hydrophobic properties,the special charge distribution and porosity of the surface of CMPs,the CMPs-based composite membrane prepared with AAO membrane as a support carrier easily selectively separated oil-water mixtures and adsorbed dye molecules in water.The separation efficiency of dye wastewater was basically 100%,and the flux was about 300 L m² h^-1 bar^-1,and the separation efficiency of emulsified oil was more than 99%,and the flux was more than 240 L m² h^-1 bar^-1.（2）In addition,using 1,3,5-triethynylbenzene and 3,3’,5,5’-tetrabromo-2,2’-bithiophene as monomers,potassium bromide as hard template,the self-supporting CMPs（S-CMP）membrane with a thickness of 164～260 nm was prepared by adjusting the monomer concentration.S-CMP membrane effectively captured PM of different particle sizes in the air,and the removal efficiency of PM2.5 and PM10 was 99.7%and99.9%,respectively.The S-CMP film shown excellent purification effect on the high concentration of VOCs vapor in the air.The removal efficiency of formaldehyde in the simulated air was over 97%,and the AQI value（>500）of the filtered gas was reduced to 50.（3）Finally,3,5-diiodosalicylic acid was dissolved in sodium hydroxide solution,1,3,5-triacetylenebenzene was dissolved in toluene,and self-supporting CMPs（D-CMP）membranes material with a thickness of 0.39 mm were prepared through oil/water interface polymerization.D-CMP membrane performed excellent retention performance for high concentration solid PM,and the filtration efficiency for PM0.3,PM2.5 and PM10 can reach 90.8%,99.3%and 99.9%,respectively.At the same time,based on its surface hydrophobic and lipophilic properties,D-CMP membrane effectively filtered high-concentration VOCs vapor in the air,and the HCHO,TVOC content and AQI index of the filtered air met the environmental requirements.