Formation and thermo-physical properties of aerogel ceramic blanket composites synthesized via scalable atmospheric pressure process with methyltrimethoxysilane precursor

Abstract

The fragility of silica-based aerogels limits their potential use in various applications. These exceptional materials can be immobilized on more flexible insulation materials to form materials called ‘aerogel blankets’. In situ, sol-gel deposition is one way to synthesize aerogel material directly on the fibrous matrix. This study presents aerogel blankets’ formation and thermophysical performance obtained by in situ deposition of a methyltrimethoxysilane (MTMS) precursor prepared with sodium dodecyl sulphate surfactants. X-ray diffraction analysis indicates increased peak intensities, suggesting a more organized crystalline-like structure. Corresponding Raman spectroscopy and transmission electron microscopy (TEM) observations corroborate the results, highlighting the surfactant’s role in promoting structural order within the aerogel. A distinct silica spherical structure was also observed in the TEM analysis. The process was carried out at ambient pressure conditions; thus, the process is scalable for large-volume production. The MTMS concentration of the sol varied in the range of 5 to 30 wt.%, resulting in different aerogel characteristics deposited onto the ceramic fiber matrix. Samples were characterized mainly for their thermal, mechanical, and morphological properties. Remarkably, the thermal conductivity performance of the obtained composite blanket showed 30% lower heat conductivity than the pristine ceramic blanket.