二氧化硅气凝胶制备条件对热导率的影响

The impact of preparation conditions of silica aerogel on the thermal conductivity

中文关键词: 二氧化硅气凝胶  实验研究  热导率  缩聚反应

英文关键词: silica aerogel  experimental investigation  thermal conductivity  condensation polymerization

中文摘要:

      二氧化硅(SiO2)气凝胶由于其内部的多孔网状结构与气体填充,热导率极低,可应用于多种保温隔热材料。本文通过实验研究了二氧化硅气凝胶的热学性能,并分析了不同水解时间、蒸馏水体积、反应物体积比、pH值对其热学物性参数的影响规律。结果表明,在所研究的范围内,随着水解时间的增加,二氧化硅气凝胶热导率减小；随着反应物体积比、蒸馏水体积和pH值的增加,二氧化硅气凝胶热导率先减小后变大。

英文摘要:

      The thermal conductivity of silica aerogel is greatly low due to the porous reticular structure and gas in its interior. So, the silica aerogel can be applied to a variety of thermal insulation materials. The thermal property of silica aerogel was studied experimentally and the rule of impact of different hydrolysis time, volume of distilled water, reactant volume ratio and pH value on its thermal parameters were analyzed in the paper. The results show that, within the scope of the study, the thermal conductivity of silica aerogel decreases with the increase of hydrolysis time; The thermal conductivity of silica aerogel decreases first then increases with the increase of the volume ratio of Tetraethyl orthosilicate (TEOS) and Ethanol absolute (EtOH), volume of distilled water and pH value.