分散聚合法制备粒径可控的单分散聚苯乙烯微球

以苯乙烯(St)为单体,偶氮二异丁腈(AIBN)为引发剂,聚乙烯吡咯烷酮(PVP)为分散剂,乙醇/水为分散介质,采用分散聚合法制备了聚苯乙烯(PS)微球。研究了单体、引发剂、分散剂的浓度,分散介质中乙醇与水的比例对制备PS微球粒径及粒径分布的影响。采用傅立叶红外光谱(FT-IR)、透射电子显微镜(TEM)、场发射扫描电镜(FE-SEM)、动态光散射(DLS)等手段,对微球的组成成分、表面形貌、粒径及其分布进行了表征。结果表明,在合适条件下,分散聚合法可以制备粒径200～1000nm范围内可控、球形度良好、表面光滑、互不粘连的单分散PS微球。

Preparation of Size Controllable Monodispersed Polystyrene Microspheres by Dispersion Polymerization

Polystyrene microspheres were prepared by dispersion polymerization of styrene in the medium of ethanol and water,using azodiisobutyronitrile(AIBN) and poly(vinylpyrrolidone)(PVP) as the initiator and stabilizer,respectively.The effects of the reaction parameters,such as the monomer concentration in the systems,the initiator dosage,the stabilizer dosage and the ratio of ethanol and water,on the particle size and the size distribution were investigated.Polystyrene microspheres were observed by transmission electron microscopy(TEM),field emission scanning electron microscopy(FE-SEM),Fourier transform infrared(FTIR) spectroscopy,dynamic light scattering(DLS),etc.It is shown that experimental parameters are in conformity with the mechanism of forming microspheres,the average size of as-prepared microspheres ranges from 200 to 1000 nm.The conclusions also show that only specific sets of conditions may produce particles with a narrow distributed size distribution.