The Study Of Improving Of PS Template Surface Character And Preparing Of Core-Shell Materials

In the most hybrid materials, core-shell materials have been one of the focuses of many scientists. Due to their features in structure, size and composition, core-shell materials have unusual properties in optics, electronics and chemistry. Moreover, we can produce hollow microspheres easily after removing the cores. There are many applied fields for hollow microspheres such as catalysis, micro-sensors and drug delivery systems. Nowadays, the most effective approach to producing core-shell materials is template method, especially hard template method. There are many merits such as simplicity, high repeating ratio and being foreseeable for this method. However, the key to the method is improving the surface character of hard template. Many scientists of this field have been devoting themselves to finding a simple and common method to adding electrostatic forces of core and shell materials.In this article, monodispersed polystyrene (PS) microspheres templates were produced by dispersion polymerization, and then we improved the surface character of the template by simple sulfonation with concentrated sulfuric acid. Using this kind of sulfonated PS spheres as core templates, PS-polyaniline (PANI) and PS-polypyrrole (PPY) core-shell microspheres were produced. After removing the cores, uniform hollow conductive polymer microspheres were obtained. Transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), infrared spectra (IR), thermogravimetric analysis (TG), cyclic voltammetry (CV) and four-probe technique were used to character the resulting products.Moreover, PS-ZnO core-shell microspheres and hollow ZnO capsules were obtained by using the same sulfonated PS templates and combining ZnO hydrothermal producing system. We also used unsulfonated PS templates and not used any templates to produce ZnO under the same experiment condition. According to the experiment and characterization results, the importance of surface character of the template was improved. However, we had not obtained PS-Fe3O4 core-shell and hollow Fe3O4 materials using the same templates.Finally, using monodispersed PS templates and combing the Solute Co-diffusion Method (SCM), we produced mono-sized PS microcapsules. Compared with the samples produced by using multi-phase emulsion method, the merit of the mono-sized template was proved.