Aerogel Composites Produced from Silica and Recycled Rubber Sols for Thermal Insulation.

Hydrophobic rubber-silica aerogel panels (21.5 × 21.5 × 1.6 cm 3 ) were fabricated from silica and rubber sols and reinforced with several fiber types (recycled tire textile fibers, polyester blanket, silica felt, glass wool). A recycled rubber sol was prepared using peracetic acid and incorporated for the first time in TEOS-based sol-gel chemistry. The composites exhibited good thermal stability up to 400 °C and very low thermal conductivity, in the superinsulation range when using polyester fibers (16.4 ± 1.0 mW·m -1 ·K -1 ), and of 20-30 mW·m -1 ·K -1 for the remaining fibers. They could also endure cyclic compression loads with near full recovery, thus showing very promising properties for insulation of buildings.