A Practical Approach for Producing Hydrophobic and Elastic Aerogels by Ambient Pressure Drying

Abstract

Hydrophobic and elastic aerogels derived from methyltrimethoxysilane (MTMS) precursor were prepared by ambient pressure drying under various processing conditions, and their morphology and physical and mechanical properties were characterised and evaluated. The results of this study demonstrated that for inherently hydrophobic gels like MTMS based gels, high temperature ageing is a practical and effective means to reduce volume shrinkage and produce low bulk density monolithic aerogels at ambient pressure, without the need of any solvent exchange and surface modification. By using this simple method, we were able to produce an aerogel with a bulk density as low as 0.064g/cm3. The results also revealed a significant difference from that previously reported in the literature.

Insulation Properties of the Monolithic and Flexible Aerogels Prepared at Ambient Pressure

“…Recently, we have developed several processes for preparing monolithic areogels with low bulk densities, at ambient pressure without the need for any solvent exchange and surface modification [3][4][5][6]. This has been achieved through the use of the specified precursors methyltrimethoxysilane or a combination of methyltrimethoxysilane (MTMS) and vinyltrimethoxysilane (VTMS), and specifically tailored processing conditions.…”

“…This has been achieved through the use of the specified precursors methyltrimethoxysilane or a combination of methyltrimethoxysilane (MTMS) and vinyltrimethoxysilane (VTMS), and specifically tailored processing conditions. These precursors used have largely determined the flexible and hydrophobic characteristics of the resultant aerogels [3][4][5][6][7].…”