Synthesis of silica aerogels:: Influence of the supercritical CO2 on the sol-gel process

被引：42

作者：

Smirnova, I ^{[1
]}

Arlt, W ^{[1
]}

机构：

[1] Tech Univ Berlin, Fachgebiet Thermodynam & Therm Verfahrenstech, D-10623 Berlin, Germany

来源：

JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY | 2003年 / 28卷 / 02期

关键词：

silica aerogels; supercritical CO2; reaction enhancement; sol-gel process;

D O I：

10.1023/A:1026072914972

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

The synthesis of silica aerogels was modified by addition of supercritical CO2 during the sol-gel process. It was shown, that CO2 acts as a catalyst and accelerates the gelation significantly. This effect was studied under a multitude of experimental conditions. The influence of the precursor concentration, temperature and the nature of the catalysts and solvent on the gel formation in presence of CO2 was studied. Several gels obtained by this method were dried and transparent silica aerogels were produced.

引用

页码：175 / 184

页数：10

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