种子溶胀法制备单分散多孔聚合物微球的溶胀动力学研究

以微米级聚苯乙烯为种球,进行了两步种子溶胀法制备多孔聚合物微球的溶胀动力学研究,用光学显微镜、马尔文粒度分析仪、扫描电镜(SEM)和比表面积孔径分布测定仪(BET)等手段,对微球的溶胀形貌和孔结构进行了表征,优选出较好的溶胀条件是:以邻苯二甲酸二丁酯为溶胀剂,用超声乳化方式制备乳液,单位质量种球所用溶胀剂量为1.5mL,在35℃下10h即可完成溶胀,得到粒径分布良好的活化微球。研究发现,超声乳化分散方式的引入,可将溶胀时间由传统的24h缩短至10h,这可能是由于超声波的空穴效应所产生的巨大磁场加速了溶胀平衡状态建立的缘故。

Swelling Dynamics of Seed-swelling Copolymerization for Preparing Monodisperse Porous Microspheres

The swelling dynamics of two-step seed swelling copolymerization for preparing monodisperse porous microspheres was studied using the uniform polystyrene(PS) particles as the seed.The surface features and pore characteristic of the swelling beads were analyzed by optical microscope,particle size analyzer,SEM and BET method.Optimal swelling conditions for the preparation of uniformly sized polystyrene particles were found as follows.Swelling activation agent was dibutyl phthalate(DBP),swelling temperature was 35 ℃,dispersion manner was ultrasonic assisted magnetic dispersion,and DBP dosage to 1 g PS seed was 1.5 mL.It was found that the particle size distribution became narrower and swelling time was shortened from more than 24 h to 10 h with the introduction of ultrasonic dispersion,which was attributed to the cavitation effect of ultrasonic and the huge magnetic field action arising therefrom,speeding up the equilibrium of swelling process.