单分散球形SiO_2的制备及其分散体系的流变性能  

Preparation of monodisperse spherical SiO_2 and rheological property of its suspension

作　　者：阮建明[1] 王亚东[1] 伍秋美[1] 周忠诚[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2007年第5期825-829,共5页Journal of Central South University:Science and Technology

摘　　要：采用溶胶-凝胶法,在乙醇介质中氨催化水解正硅酸乙酯制备单分散球形SiO2微粒,考察了硅烷偶联剂作为分散剂对SiO2粉末颗粒分散性能的影响。采用透射电镜对未添加分散剂制备的SiO2粉末和添加硅烷偶联剂后制备的SiO2粉末进行形貌观察,并对以硅烷偶联剂作分散剂制备的SiO2粉末进行X射线衍射、红外光谱分析和表征,采用应力控制流变仪对SiO2/PEG分散体系的流变性能进行测定与分析。研究结果表明:硅烷偶联剂显著提高了SiO2粉末颗粒的分散性能,粉末颗粒呈单分散的球形粒子,所制备的SiO2粉末样品为非晶态物质;SiO2/PEG分散体系具有剪切变稀和可逆的剪切增稠现象。Monodisperse SiO2 spherical particles were prepared by sol-gel using hydrolyzation of TEOS in ethanol, with ammonia as activator. The influence of silane coupling agent on the dispersibility of SiO2 powder was studied. The two kinds of powders prepared without dispersant and prepared with silane coupling agent were characterized with transmission electron microscrope （TEM） and the powder dispersed by silane coupling agent was characterized with X-ray diffraction （XRD） and infrared spectrum （IR）, The theological property of SiO2/PEG suspension was studied by stress controlled rheometer, The results show that the silane coupling agent improves dispersibility of SiO2 powder obviously, The monodisperse sphere particles dispersed by silane coupling agent is amorphous. The SiO2/PEG suspension shows shear thinning and reversible shear thickening behavior.

关 键 词：单分散 二氧化硅 分散体系 流变性 剪切增稠 

分 类 号：O648[理学—物理化学]