水玻璃制备SiO_2气凝胶微球的研究  

Studies on preparation of silica aerogel microspheres from water glass

作　　者：杨海龙[1] 倪文[1] 陈德平[1] 封金鹏[1] 张世利[1] 刘凤梅[1] 

机构地区：[1]北京科技大学金属矿山高效开采与安全教育部重点实验室,北京100083

出　　处：《功能材料》2008年第8期1395-1397,1401,共4页Journal of Functional Materials

基　　金：国家高技术研究发展计划(863计划)资助项目(2003AA302610)

摘　　要：为拓展SiO_2气凝胶的应用范围和效率,弥补SiO_2气凝胶微球制备技术中的不足,以水玻璃为硅源采用液滴成球工艺在单一油相中制备了直径为毫米级别的SiO_2气凝胶微球,并研究了微球原始粒径和干燥工艺对其线性收缩率的影响,结果表明微球收缩率随原始粒径的减小而降低,干燥工艺不同收缩率也有差异。经三甲基氯硅烷(TMCS)表面改性后再超临界干燥的样品收缩率最小,X射线衍射(XRD)和孔隙度分析仪对其测试表明为无定型结构,所有孔径均<80nm,平均孔径为5.5nm,比表面积为181m^2/g。In order to improve the application scope and the efficiency of silica aerogel and compensate the shortage in prepare techniques for siliea aerogel mierospheres, silica aerogel microspheres, whose particle size was in millimeter scopes, were obtained from water glass by adopting ball-dropping technology in a single oil phase, the influences of primary particle size and drying technology on the linear shrinkage rate of it were investigated, and it was found that the shrinkage rate decreased with decreasing primary particle size and varied with the change of drying technology. The sample, which is modified by using modification agent trimethylchlorosilane （TMCS） and then dried via supercritical fluid drying, has the minimum shrinkage rate, the results measured by using pore size distribution technique show that all its pore sizes are less than 80nm with specific area is 181m^2/ g and average pore size is 5.5nm, and it characterized by using X-ray diffraction （XRD） is an amorphous material.

关 键 词：SiO2气凝胶微球 水玻璃 收缩率 

分 类 号：TB34[一般工业技术—材料科学与工程] TB321