Preparation of Nubbly Silica Aerogels and Their Properties in Sodium Silicate at Ambient Pressure
HOU Chentao
LI Yanjie
HAN Yan
ZHANG Xiaoqian
ZHANG Qing
LIU Chenglin
ZHAO Caiyan
Abstract：Monolithic silica aerogels was prepared with low density and high performance under ambient pressures drying.The experiment results demonstrated that when the average density and specific surface area of preparedsilica aerogels are 0.11～0.15 g/cm3 and 450～650 m2/g,respectively,and the porosity is 90％～98％.It has higher hydrophobicity and the rate of adsorption of methyl red can reach up to 80％.The best preparation scheme is that ethylene glycol and acetamide adding into sodium silicate solution at 20％,the molar ratio of sodium silicate to ethylene glycol and acetamide was 1∶1∶2,ethanol as a displacer,trimethyl chlorosilane/l∶5 ethanol mixture as surface modification agent,replacement and modification time were 72 h and 24 h.The preparation of silica aerogels are affected by concentration and quantity of acid,hydrophobic modification type and proportion of the agent,drying process,adding ethylene glycol and acetamid.The hydrophobic properties and adsorption properties of the prepared silica aerogels is very well.
Keywords：sodium silicatesilica aerogelsambient dryingnubbly
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 61-65 )