软模板法制备单分散中空有机硅微球

Preparation of Monodisperse Hollow Organic Silica Microspheres by Soft Templating Method

通过硅氧烷单体在碱性条件下的水解-聚合反应,制备出了单分散乳液,研究了乳化剂HLB、反应时间、乳化剂用量、单体用量等因素对乳液的影响。然后以该乳液为模板、有机硅为壳层进行包覆,得到了中空微球。采用纳米粒度及Zeta电位分析仪、SEM、TEM、EDS、FTIR对乳液及中空微球进行表征。结果表明,在室温条件下,反应时间为6h时能够制备出单分散性较好的乳液,通过改变乳化剂用量、单体用量,能够实现对乳液粒径的调控,调控范围346~472 nm。以该乳液为模板进行缓慢包覆,当乳化剂质量分数低于0.003%时,能够得到形貌规整的单分散中空微球,中空微球的主要成分为有机硅。与硬模板法相比,该模板通过乙醇洗涤即可除去,制备过程较为简单。

Monodisperse emulsions were prepared through a hydrolysis-polymerization process of siloxane monomer under alkaline condition.The influences of HLB value of emulsifier,reaction time,emulsifier content and monomer content on the emulsion properties were studied.Then,hollow microspheres were prepared by using emulsion as template and organic silicone as shell.The emulsions and microspheres were characterized by Zetasizer,SEM,TEM,EDS and FTIR.The results showed that highly monodisperse emulsions were prepared at room temperature for 6 h.By changing the amount of emulsifier and original monomer,the particle size of the emulsion could be controlled in the range of 346~472 nm.The monodisperse hollow microspheres with regular morphology could be obtained when the mass fraction of the emulsifier was less than 0.003%by using the emulsion as template,and the main component of hollow microspheres was organic silica.Comparing with the hard templating method,this preparation process was relatively simple and the template could be removed by washing with ethanol.