Preparation And Characterization Of Functional Polymer Magnetic Nanoparticles

The Fe₃O₄ nanoparticles modified by monomolecular oleic acid was prepared by means of chemical co-precipitation method firstly. Some properties such as particle size, oleic acid content were characterized. The particle size of the product was about 10 nm and the content of oleic acid was 12.70%. Then A core/shell structure of magnetic nanoparticles covered by polymer was designed and the self-assembly method which was suitable for formation of such structure were described. Self-assembly aggregations of 4-vinylbenzoic acid were formed around the Fe₃O₄ modified by monomolecular oleic acid. At last in situ polymerization occurred with initiator of of K2S2O4. The structures and compositions of the polymer magnetic nanoparticles were characterized by IR spectra, TEM, thermal analysis etc. The results showed magnetic nanoparticles coated with polymeric layer were fabricated successfully. The content of magnetite, polymer and -COOH are 74.01%, 15.22% and 1.05 mmol/g around respectively, which shows the advantages of self-assembly method to make polymer magnetic nanoparticles.At the same time, the adsorption mechanism between the Fe₃O₄ and oleic acid were studied by testing and supposition. Finally, the initial applications of polymer magnetic nanoparticles in biology were also studied in this paper.