摘要
以廉价水玻璃为硅源,经溶胶-凝胶工艺和超临界干燥技术制备了SiO2气凝胶块体,并研究了制备条件对其成胶时间的影响。结果表明,成胶时间随稀释剂用量(水或无水乙醇)的减少和温度的升高而缩短,但随NH3.H2O添加量的增加先缩短后延长,并且以无水乙醇为稀释剂时较以水为稀释剂时短。典型样品的扫描电镜(SEM)表明纳米尺寸球形骨架颗粒构成了连续网状纳米多孔结构,并且由N2吸附测试得知所有孔径均<61nm,平均为6.3nm,比表面积为297.7m2/g。
Using cheap water glass as silica source, monolithic silica aerogel was prepared by sol-gel process and supercritical drying technique, the effect of preparing conditions on the gelling time of it was investigated. It is found that the gelling time decreases with reducing amount of diluents （water or alcohol） and with increasing temperature. The gelling time initially decreases and then increases with increasing dose of NH3· H2O and it when alcohol as diluent is shorter than it when water as diluent. The results of the typical sample characterized by using scanning electron microscopy （SEM） and nitrogen adsorption-desorption technique indicate that its continuous nano-mesoporous network structure is constituted by nanoscaled skeletal sphere particles, and all its pore diameters are less than 61nm with specific area is 297.7m^2/g and the average pore diameter is 6.3nm.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2008年第9期1525-1527,1531,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)
