Silica aerogels have extremely low thermal conductivities, potentially making them effective thermal insulators. In this study, the thermal conductivities of various samples were explored using the Transient Plane Source (TPS) Method. Samples of the silica aerogels were approximately 1.3 cm thick and between 4.1-4.3 cm in diameter, and were tested at different temperatures. Results showed that as the temperature of the samples increased from 25-50 °C, thermal conductivity increased exponentially. As ...
Silica aerogels (SA) are identified as one of the most advanced thermal insulating materials to date, however, their range of applications is limited due to a high sensitivity to moisture and issues with brittleness. This study highlights the design and fabrication of a new and improved thermal insulation material, robust flexible hybrid silica nanofiber (SNF)-SA membranes. To allow for higher thermal insulating characteristics, these membranes form an interpenetrating network ...
In this research silica aerogels were incorporated into PVC fabrics by the research team to improve the overall performance of the fabrics. The aerogel was added in percent fractions of 0, 2, 3, and 4%. Comprehensive analysis of physical and mechanical properties was also performed. Thermal conductivity measurements revealed that the addition of the silica aerogel had reduced the thermal conductivity of the fabric; when 4% silica was added, the thermal conductivity dropped by 26%. As ...
Ambient pressure dried hydrophobic silica aerogel monoliths were prepared via simultaneous solvent exchange and surface modification in order to minimize volume shrinkage and density. At room temperature, the obtained silica aerogels had a low density of 0.096 g/cm³, a high surface area and hydrophobicity, and a low thermal conductivity of 0.0217 W/m·K. The effect of heating on these properties was also determined. After the aerogel had been heated to 300°...
The effective thermal conductivity of a commercial silica aerogel is determined at various gas pressures ranging from 0.001 Pa to 1 MPa in order to determine the contribution of gaseous heat conduction to the effective thermal conductivity of nano-porous materials. It was determined that the gas pressure had a significant effect on the effective thermal conductivity of the aerogel and that the contribution of gaseous heat conduction was greater than the gas ...