| Fe3O4-based magnetic polymer composite materials have been applied in many areas, including magnetic separation, catalysis, biomedical, bio-medicine and so on, because of their unique superparamagnetic, biocompatibility and excellent optical, catalytic and adsorption properties.In this thesis, we have focused on the studies of synthesis, structure, morphology, magnetic property, adsorption property and catalytic activity of the Fe3O4-based magnetic polymer composite materials. We have studied the synthesis, magnetic separation and catalytic property of Fe3O4-based magnetic polymer composite materials which have different morphology, structure, composite.(1) Ten different magnetic porous microspheres (FMD) were synthesized by modified suspension polymerization of methacrylate and divinylbenzene, in the presence of oleic acid coated Fe3O4nanopaticles, using n-hexane, cyclohexane, toluene as small molecules progent, respectively. The morphologies and properties of the magnetic porous microspheres were charaterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), superconducting quantum interference device (SQUID), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TGA), and X-ray powder diffraction (XRD). The pore size distribution and the specific surface area of magnetic porous microspheres were measured by nitrogen sorption and mercury porosimetry technique. The obtained microspheres were applied in the removal of phenol from aqueous solution, and the concentration of phenol aqueous solutions was measured by ultraviolet analyses (UV). It was found that magnetic porous microspheres had the ink bottle shape hole, some minor-caliber and big celiac hole. The amount and type of progents complicated and dramaticlly affected the pore structure of FMD microsphere. The magnetic porous microspheres possessed a high specific surface area by using n-hexane and cyclehexane as porogent. It was further demonstrated that the amounts of divinylbenzene and methacrylate, the volume ratio of porogents, and the dosage amount of ferrofluids affected the specific surface area of magnetic microspheres as well. Furthermore, results showed that obtained magnetic microspheres had a superparamagnetic behavior at room temperature due to the existence of Fe3O4crystalline structure. The results showed that magnetic microspheres had a high adsorption capacity and high separation efficiency (removal ratio reach to99.32%), due to their porous structure, polar groups, and superparamagnetic properties.(2) Ten kinds of Fe3O4/poly(styrene-co-divinylbenzene) microspheres were synthesized by emulsion polymerization with oleic acid coated Fe3O4nanoparticles as magnetic core, and styrene and divinylbenzene as monomer. Then, the above obtained microspheres were used to fourteen kinds of prepare Fe3O4/poly(styrene-co-divinylbenzene)/SiO2microspheres by sol-gel technology in the presence of tetraethoxysilane. The effects of the composite of monomer, the kinds of surfactant, and the content of oleic acid coated Fe3O4nanoparticles on the morphology, magnetic content and size of microspheres were investigated. The magnetic hybrid FesU4/poly(St-co-DVB)/SiO2/TiO2photocatalyst was prepared by one-pot solvothermal reactions by using the above silica modified microspheres as magnetic matrix. We investigated the catalytic property of as-prepared magnetic hybrid photocatalyst on the degration of RhodamineB (RhB). The results showed that the magnetic hybrid photocatalysts exhibited good photocatalytic activity under UV light irradiation and could be reused five times by magnetic separation without major loss of activity, and the degradation ratio of RhB still reached to90%.(3) Three series of magnetic poly(hexachlorocyclotriphosphazene-co-4,4’-dihydroxydiphenylsulfone) were synthesized with different structures and morphologies. Firstly, Fe3O4microspheres with hollow porous structures were prepared by hydrothermal method, and were used as the magnetic core to fabricate hollow porous Fe3O4/mSiO2and hollow Fe3O4/nSiO2microspheres, in the presence of TEOS and CTAB; Then, hollow porous Fe3O4/mSiO2/PZS and hollow Fe3O4/nSiO2/PZS microspheres were prepared by using BPS and HCCP as the monomer, hollow porous Fe3O4/mSiO2and hollow Fe3O4/nSiO2microspheres as magnetic matrix, respectively. Secondly, Fe3O4/OA nanoparticles were prepared by co-precipitation method, and were used as magnetic core to frabricate Fe3O4/PZS magnetic nanowires by inclusion polymerization with BPS and HCCP as monomer, in the presence of TEA. Thirdly, Fe3O4/PZS magnetic nanowires were prepared by in-situ polymerization method with as-prepared Fe3O4nanowires as magnetic core, BPS and HCCP as monomer, in the presence of TEA. The effects of experimental conditions on the morphology, size and performance of as-synthesized products were investigated. The morphology, structure and magnetic content of obtained products were examined by means of SEM, TEM, TGA and XRD, respectively. Moreover, the particle size of the products was characterized by dynamic light scattering (DLS) and nanomeasurer analyses, and the magnetic property of the products was measured by SQUID, and the specific surface area and pore structure of the products were characterized by nitrogen adsorption-desorption analyzer. In addition, the above-prepared magnetic polyphosphazene-containing materials were used as magnetic matrix to prepare Fe3O4/mSiO2/PZS/Fc microspheres by the esterification reaction, and magnetic polyphosphazenes-containing gold nanocatalysts by the chemical deposition method with HAuCl4as gold source, respectively. Furthermore, catalytic activity and reusability of these magnetic polyphosphazenes-containing gold nanocatalysts was investigated by choosing a model reaction, reduction reaction of n-nitroaniline to benzenediamine by NaBH4. It was found that as-prepared polyphosphazenes-based magnetic nanocatalysts had good hydrophilicity, good thermal stability, biocompatibility and better magnetic response ability and so on, and had good prospect in the field of industrial applications. |
PDF Full Text Request