复合材料科学与工程Issue(11)：14-21,8.DOI:10.19936/j.cnki.2096-8000.20241128.002
硅酸钠为前驱体的SiO2气凝胶制备及性能研究
Preparation and properties of SiO2 aerogel with sodium metasilicate as precursor
摘要
Abstract
In this experiment,sodium silicate was used as the silicon source to prepare SiO2 aerogel by drying under normal pressure.The influence of different sodium silicate mass fraction and chemical desiccant content on the vibrating density,specific surface area,pore volume and pore diameter,microstructure and other indicators of SiO2 aerogel was mainly explored.The best washing efficiency was determined and the effect of Na+on the performance of aerogels was analyzed.The results show that when the mass fraction of sodium silicate is 7wt%,the prepared aerogel has excellent performance,specifically,the gel time is 3 min;the compaction density can be as low as 0.209 g/cm3;the higher porosity is 90.5%.When n(DCCA)∶n(Si)=2∶1,the aerogel has a larger specific surface area of 531.69 m2/g and a higher total pore volume of 2.51 ml/g,and the pore structure is the most uniform.When remo-ving Na+through water washing,the washing temperature should be controlled at around 50℃,and the water con-sumption should be controlled at around 15 times the amount of accumulated water.Four washes can remove 97.24%of the original Na+.Finally,it is found that the residual Na+will have a negative impact on the density and thermal conductivity of SiO2 aerogels,so the process of removing Na+is very important.关键词
SiO2气凝胶:化学干燥剂:水洗工艺/复合材料Key words
SiO2 aerogel/chemical desiccant/water washing process/composites分类
通用工业技术引用本文复制引用
徐长伟,孙沈涵,张忠伦,王明铭..硅酸钠为前驱体的SiO2气凝胶制备及性能研究[J].复合材料科学与工程,2024,(11):14-21,8.基金项目
山东省"十四五"重点研发计划项目(2021SFGC0903) （2021SFGC0903）
