作者：Guangyu Liu, Han Zhang, Xinlin Yang*, and Yongmei Wang
关键字：Silica/polymer core-shell hybrids; Core-shell microsphere; Distillation precipitation polymerization
论文来源：期刊
具体来源：Polymer, 48 (20), 5896-5904 (2007). DOI: 10.1016/j.polymer.2007.07.068
发表时间：2008年
Monodisperse silica/polydivinylbenzene (SiO2/PDVB) and silica/poly(ethyleneglycol dimethacrylate) (SiO2/PEGDMA) coreeshell hybrid microspheres were prepared by a two-stage reaction with silica particles’ grafting of 3-(methacryloxy)propyltrimethoxysilane (MPS) as core and PDVB or PEGDMA as shell, in which the MPS-modified silica core with diameter of 238 nm was synthesized by Stober method and subsequently grafted with MPS as the first-stage reaction. The PDVB or PEGDMA shell was then encapsulated over the MPS-modified silica core by distillation precipitation polymerization of divinylbenzene (DVB) or ethyleneglycol dimethacrylate (EGDMA) in neat acetonitrile with 2,20-azobisisobutyronitrile (AIBN) initiator as the second-stage reaction. The encapsulation of PDVB and PEGDMA on modified silica core particles was driven by the capture of DVB or EGDMA oligomer radicals via the vinyl groups on the surface of the modified silica cores during the second-stage polymerization in the absence of any stabilizer or surfactant. The shell thickness of the coreeshell hybrid particles was controlled by the feed of DVB or EGDMA monomer during the polymerization. Hollow PDVB or PEGDMA microspheres with various shell thickness were further developed after selective removal of the modified silica cores with hydrofluoric acid. The resultant coreeshell hybrid materials and hollow microspheres were characterized by transmission electron microscopy (TEM), and Fourier transform infrared spectra (FT-IR).