Based On Polystyrene Two Core-shell Composite Microspheres Preparation And Characterization

In this thesis, two polystyrene core-shell nanocomposites were prepared from polystyrene using two novel methods. In the first step, paraffin/polystyrene nanocomposite was synthesized by Pickering emulsion polymerization; and the second, a spherical polyelectrolyte brush was used as templates to synthesis polystyrene/ silicon composite microspheres. Various parameters influencing the microspheres morphology and functional mechanism were analysed .Normally, solid particles were used as stabilizers in Pickering emulsion. In this thesis, polystyrene was employed to prepare paraffin/polystyrene composite microspheres form which single scattered polystyrene microspheres were obtained. With strong mechanical agitation, paraffin and polystyrene were self-assembled to form paraffin/polystyrene composite microspheres. AFM, TEM, SEM and other testing method were used to characterize these microspheres. Results showed that the core was paraffin microspheres and polystyrene was the wall film of the globular structures.Furthermore the paraffin microspheres was completely covered by polystyrene.Polystyrene/silicon composite microspheres were synthesized with spherical polyelectrolytes brush as templates. polystyrene nuclear was synthesized by emulsion polymerization. In the end of emulsion polymerization, initiator was added and UV light initiated the photoemulsion polymerization to graft PAA brushes. 100nm and single scattered particle spherical polyelectrolyte brushes (SPB) were synthesized. Teos was added in an alkali catalysis condition and eventually polystyrene/silicon composite microspheres were obtained. The polystyrene/silicon composite microspheres were charaterized by AFM, SEM, FE-SEM, IR, TG.