Flexible hybrid aerogels prepared under subcritical conditions

Abstract

A new flexible insulator was developed, consisting of a silica–latex-fiber nanocomposite aerogel that combines the lightness and insulating properties of silica aerogels with the mechanical properties of silica–latex hybrids and the flexibility of fibers. This was accomplished by coating selected insulating fibers (polyester and glass) with a silica–polymer hybrid aerogel, synthesized in situ by a two-step sol–gel process, consisting of the acidic co-hydrolysis of TEOS and trimethoxysilyl-grafted latex nanoparticles in excess water, followed by basic co-condensation. The hybrid coating has improved mechanical properties that allow its drying under subcritical conditions. The outstanding properties of the insulating blankets produced render them extremely attractive for high-technology applications, and, due to the low energy consumption process, they may even displace the commonly used mineral wool, by presenting a best value-for-money compromise.