摘要
以低成本的水玻璃为硅源,水为反应物及溶剂,采用溶胶-凝胶法和常压干燥法制备SiO_2气凝胶。并通过SEM、TEM和XRD等测试手段对气凝胶进行表征,实验研究了水玻璃和水的比例,硅酸的pH、改性溶剂的比例和干燥条件等对SiO_2气凝胶性质的影响。结果表明:工业水玻璃与水的体积比为1:5,pH调节为6,在50℃下老化3h,采用三甲基氯硅烷(TMCS)、正己烷和乙醇的混合液进行改性。其中,乙醇与三甲基氯硅烷(TMCS)体积为2:3,加入三甲基氯硅烷(TMCS)的体积比为20%,在50℃下置换72小时,130℃下干燥制备得到的SiO_2气凝胶的性能最好。
Using industrial grade sodium silicate as silicon source and water as reactant and solvent, SiO2 aerogel was prepared by ambient drying method. The aerogel structure and properties were characterized by SEM, TEM and XRD, the effects of the ratio of sodium silicate and water, pH value, the ratio of surface modification agent and drying condition were studied. Results show that the optimum conditions for preparing SiO2 aerogel are as follows： the volume ratio of sodium silicate and water at 1：5, pH value at 6, 3h aging time at 55 ℃, surface modified by the mixed liquor of ethanol, hexane and trimethylchlorosilane（TMCS）, the volume ratio of TMCS at 20%, 72 h replacement time at 50 ℃, and the drying temperature at 130 ℃.
出处
《中国陶瓷工业》
CAS
2016年第2期22-25,共4页
China Ceramic Industry
基金
山西省科技重大专项项目(20131101016)
