二氧化硅-聚丙烯腈核-壳结构复合纳米粒子的制备与表征

以甲基丙烯酸-3-（三甲氧基硅基）丙酯改性的SiO2纳米粒子为种子，采用乳液聚合法制备了粒径分布较窄的SiO2-聚丙烯腈（SiO2-PAN）核 壳结构复合纳米粒子。采用动态光散射、傅里叶红外光谱、透射电镜和扫描电镜表征了复合纳米粒子的粒径及分布、组成、形态和结构，并研究了表面活性剂的加入方式、反应温度及交联剂的引入对制备SiO2-PAN复合纳米粒子的影响。结果表明：SiO2-PAN复合纳米粒子为核 壳结构。采用半连续加入表面活性剂的方法，可以成功抑制乳液聚合中次级粒子的生成。通过增加表面活性剂的初始加入量、加快表面活性剂的补加速率，或降低反应温度，可使SiO2-PAN复合纳米粒子的粒径变小。反应温度的降低以及交联剂的引入使SiO2-PAN复合纳米粒子的表面变得平滑。

Preparation and Characterization of Silica Polyacrylonitrile Core Shell Composite Nanoparticles

Narrowly-distributed silica-polyacrylonitrile(PAN) core-shell composite nanoparticles were prepared via emulsion polymerization using 3-(trimethoxysilyl)propyl methacrylate-modified silica nano-particles as the seeds. Dynamic light scattering, Fourier transform infrared spectroscopy, transmission electron microscopy and scanning electron microscopy were used to characterize the size, composition, structure and morphology of nanoparticles. The effects of the feeding mode of surfactant sodium dodecyl sulfate (SDS), the reaction temperature and the introduction of crosslinker on the synthesis of the composite nanoparticles were investigated. Results show that the structure of the silica-PAN composite nanoparticles is core-shell. The semi-continuous feeding of SDS can efficiently inhibit the production of secondary PAN nanoparticles during the emulsion polymerization. When the initial surfactant amount increases, the supplement rate of surfactants increases, or the reaction temperature decreases, the size of silica-PAN composite nanoparticles decreases. Silica-PAN composite nanoparticles with relatively smooth surfaces can be obtained via reducing the reaction temperature or introducing crosslinker.