Synthesis And Characterization Of Fe₃O₄/Magnetic Polymer Microspheres

Polymer composite materials have been attracting much attention especially magnetic polymer materials. Nanometer magnetic materials are well closely linked with the areas of country economy and so on.The development of nano-technology bring importance opportunity and challenge of tradition magnetic industry. Exploitation and study of nanometer magnetic materials is currently the subject of intense research work. As novel materials magnetic materials because of its special structure and property, which have promising applications in many fields, such as aviation, electron, information, petroleum, metallurgy, chemical industry, biology, medicine, environment protect and so on. In the study of magnetic nano-materials, the application of nanometer magnetic materials which contain nano-magnetic particles and polymer materials has instructive significance in theory and practice.In this paper, Fe3O4 magnetic nanoparticles were synthesized by the chemical co-precipitation and modified by oleic acid and sodium dodecyl benzene sulfonate bilayer surfactants. The stability of the magnetic fluid is very good and can be dispersed well in polarity solvent. The magnetic fluid was as seed and through emulsion polymerition synthesized polystyrene and polymethyl methacrylate magnetic microspheres. And the influence factors of monomer, and magnetic fluid inititator were discussed in the process of synthesis. By controlling synthesis condition, we can synthesis good magnetic microspheres.Because of magnetic polymer microspheres,s distinct useness,especislly with functional groups. Inland and overseas scholars research on them deeply, The monomers witch they were most interest in styrene and methyl methacrylate, and functional groups are carboxyl groups, aldehyde groups, hydroxyl groups, amidocyanogen and so on. But the differences between the main monomers polymerization and main monomers and functional monomers co-polymerization which influence the wrap were studied little. In this paper, we contrast the differences between only styrene or methyl methacrylate polymerization and styrene-crylic acid or methyl methacrylate -crylic acid co-polymerization, and found that crylic acid is important in the process of polymerization. And it was improved when styrene and crylic acid polymerize carboxyl groups often were embedded in the microspheres, so the content of carboxyl groups reduced which on surface. Firstly the content of crylic acid was increased, secondly time of entering crylic acid into reaction solution was delayed, the crylic acid would polymerize at the surface of microspheres. We synthesize the content of carboxyl groups mainly on microspheres surface succeedly.