Design of a gum tragacanth hybrid aerogel enabling high-performance flame retardancy and thermal insulation

Abstract

The growing demand for sustainable alternatives in thermal insulation has spurred the development of eco-friendly, biomass-based aerogels. Among these, natural polysaccharide-derived aerogels have garnered significant attention due to their exceptional sustainability, biodegradability and inherent safety. In this work, a novel aerogel was engineered by integrating gum tragacanth, psyllium husk, silica gel and boric acid, employing material chemistry strategies to form a porous, crosslinked network. Boric acid served as a multifunctional crosslinking agent, enhancing structural stability and flame resistance. The flame-retardant behavior of the resulting Gt–Ph/Si/BA aerogel was assessed under direct exposure to a Bunsen burner, and the material exhibited remarkable thermal stability for up to 720 seconds without structural degradation. Furthermore, the aerogel demonstrated a limiting oxygen index (LOI) of 80 ± 0.7%, confirming its excellent flame-retardant and thermal-insulating performance. These findings underscore the potential of tree-gum-derived polysaccharides to advance the next generation of bio-based aerogels and to open avenues for exploring diverse gum sources for high-performance, sustainable insulation materials.