| The mono-disperse polymer micro-spheres with of large size have the characteristic of large specific surface area, strong absorbability and excellent condensation and so on. They are of wide prospects for using in many fields such as, chromatographic separation , standard measurement, medicine, immunity, biochemistry, information.There are several traditional methods to prepared PS: Emulsion Polymerization, Dispersion polymerization, suspension polymerization. Emulsifier-free emulsion polymerization. Emulsifier-free emulsion polymerization can be used to prepare "clean" and mono-disperse micro-spheres and the pollution from emulsifier is avoidable. Emulsifier-free emulsion polymerization becomes the newest of research. Especially, in the area of adhesives and paint. In this paper, polystyrene particles were prepared by Emulsifier-free emulsion polymerization. The results showed that it was a useful method for the preparation of uniform polystyrene particles in Micron-size.In order to prepare the polystyrene particles with controllable sizes, the influence factors on polystyrene particles diameter and size distribution have been investigated and discussed, such as monomer concentration, initiator reagent, the ionic strength of electrolyte, the temperature of polymerization, and the kinetics of Emulsifier-free emulsion polymerization of styrene were studied.1. Emulsifier-free emulsion polymerization were prepared by using styrene as monomers, KPS as initiator NaCl as electrolyte. the influence factors on PS micro-sphere diameter have been investigated. The results revealed: When other factors were kept constant, the diameter of PS micro-spheres increased with monomer concentration. When the concentration of initiator reagent increased,, the diameter of PS micro-spheres decreased; When the ionic strength increased,, the diameter of PS micro-spheres increased; The research showed that mono-disperse PS micro-spheres could be well prepared by Emulsifier-free emulsion polymerization at the reaction temperature from 65 to 85 temperature . The diameter of PS micro-spheres increased with the temperature first then decreased with the temperature.2. On the base of soap-free emulsion polymerization, Its kinetics were studied. The reaction speed of polymerization initial stage was invariable when all stages were studied. Study on kinetics Emulsifier-free emulsion polymerization was carried out by changing only one of reaction conditions. The reaction followed the mechanism of free radical copolymerization and the activation energy of reaction was about 129KJ·mol-1 Kinetic equation was represented a :Rp = k·[KPS]1.75·[St]1.46·[NaCl]0.61...
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