Fabrication And Properties Of Core-shell Structural Magnetic Polymetric Composite Microspheres

Nanomaterials have always been one of the hottest topics and the design and controlsynthesis of nanomaterials has always been of great importance since the discovery of carbonnanotubes in recent years. Core-shell structural nanomaterials, which combine the propertiesof two kinds or even more materials due to special effects, may show distinct properties andapplications, and over through the wall among different materials. As a novel and importantfunctional materials, core-shell structural magnetite polymetric composite microspheres haveshown apparent applications in the field of drug delivery, magnetic rubber and electronicrubber and have attracted significant attention all over the world. In this work, the fabricationand properties of core-shell structural magnetic polymetric composite microspheres, includingNi_0.5Zn_0.5Fe₂O₄/PANI, Ni/PANI and mesoporous MnFe₂O₄/PANI, have been carried out. Themain contest for the study can be described as follows:（1） Mono-dispersed Ni_0.5Zn_0.5Fe₂O₄magnetic nano-particles were obtained throughmicro-emulsion, which was made up of the water phase, oil phase, surfactant andco-surfactant, by using Fe, Ni, and Zn nitrogen salt as metal source and employing NaOH asprecipitant. Further, Ni_0.5Zn_0.5Fe₂O₄/PANI core-shell structural magnetic polymetriccomposite microspheres were also fabricated in a similar micro-emulsion. The SEM, TEM,FTIR and TGA result might show that PANI has been coated on the outer surface layer ofNi_0.5Zn_0.5Fe₂O₄particles and typical core-shell structures have been obtained. The VSMresults revealed that the Ni_0.5Zn_0.5Fe₂O₄particles are magnetic and the value of Hc, Mr, andMs was 3.16Oe, 2.48 emu/g and 34.10emu/g, respectively.（2） Mono-dispersed Ni microspheres and Ni/PANI magnetic composite microsphereswere also fabricated through a hydrothermal route and in-situ polymerization technique,respectively. The SEM and TEM results illustrated that both the obtained Ni microspheres andNi/PANI microspheres shown a narrow size distribution and mono-dispersion. Moreover, theTEM results directly confirmed the core-shell structure of Ni/PANI composite microspheres.In addition, it could be inferred from the FTIR and TGA results that the weight rate of coated PANI is ca. 22%. The VSM results suggested that the final products of Ni/PANI compositemicrospheres show good magnetic properties, and the value of Hc, and Ms of sample was 0Oe,and 20.04emu/g, respectively.（3） Mesoporous MnFe₂O₄magnetic microspheres and mesoporous MnFe₂O₄/PANIcore-shell structured composite microspheres were prepared through a sol-gel assisted carbonspheres template method and in-situ polymerization process, respectively. The FTIR and TGAresults confirmed the combination of PANI and MnFe₂O₄, which may reveal the core-shellstructure. The weight rate of absorbed PANI was ca. 16%. Further, the SEM and TEM resultsillustrated that the obtained MnFe₂O₄microspheres and MnFe₂O₄/PANI compositemicrospheres have a typical mesoporous structure and a well-dispersion. At last, the VSMresults confirmed the enhanced magnetic properties of MnFe₂O₄/PANI compositemicrospheres, whose Hc, and Ms value was 0Oe, and 81.10emu/g, respectively. The obtainedproducts might show significant potential applications in the field of drug delivery and so on.