Optimisation of silica-cork aerogel composites for efficient fire-retardant thermoacoustic barrier

The development and optimisation of silica-cork aerogel composites, prepared with tetraethyl orthosilicate (TEOS) and vinyltrimethoxysilane (VTMS) as co-precursors and reinforced with short cut aramid fibres is herein presented. Different synthesis parameters, such as co-precursor ratio, amount of fibres, and cork granulate dimensions, were investigated using a design of experiments approach to obtain composites with lower bulk densities and thermal conductivities. The obtained materials presented densities ranged from 0.140 to 0.190 g cm⁻³ and thermal conductivities in the superinsulation range (16.6–19.1 mW m⁻¹K⁻¹).