Lightweight superinsulating Resorcinol-Formaldehyde-APTES benzoxazine aerogel blankets for space applications
Résumé
The purpose of this study was to develop an easy to handle, light, superinsulating material for space application. A benzoxazine organic-inorganic hybrid aerogel blanket was developed in a one-pot sol-gel synthesis. Crosslinking between a resorcinol-formaldehyde matrix and a (3-Aminopropyl)triethoxysilane (APTES) matrix was confirmed by the presence of oxazine rings. The polyethylene terephtalate mat used as blanket core limited shrinkage compared with the organic matrix alone, provided mechanical reinforcement, and allowed obtaining very low apparent density materials of high user convenience. The materials’ characteristics (morphological, thermal, chemical and hydric) were found to depend on the sol formulation. Blankets featured apparent densities as low as 0.03 g cm−3, low water weight uptake (1.65 wt.%) in humid conditions (80% HR and 20 °C) or thermal conductivities as low as 0.019 W m−1 K−1 in room conditions.