Preparation of Micron Monodispersed Polystyrene Microspheres

In this paper,micron monodispersed polystyrene(PS) microspheres were synthesized by dispersion polymerization using styrene as monomer,polyvinylpyrrolidone(PVP) as dispersion stabilizer,azobisisobutyronitrile(AIBN) as initiator and ethanol-water as reaction medium.The influential factors such as initiator dosage,dispersion stabilizer dosage and reaction medium ratio on the particle size and size distribution of PS microspheres were investigated.The morphology of PS microspheres was observed by SEM.PS Particle size and size distribution were analyzed by laser particle size analyzer.Results showed that it appeared coagulation in PS particles when the initiator dosage was more than 5.0% of styrene mass or the dispersion stabilizer dosage was less than 2%,and PS microspheres,which had smooth surface and uniform spherical shape with particle size of 1.612 μm and particle size distribution coefficient of 0.357,could be obtained only at the optimized conditions as follows:styrene concentration was 10%,AIBN dosage was 2.5% of styrene mass,PVP dosage was 5.5% of styrene mass,mass ratio of ethanol to water was 90∶10,polymerization temperature was 70 ℃.