Polybenzoxazine aerogels fabricated by an aqueous solvent sol–gel method for thermal insulation

Polybenzoxazine (PBz) aerogels with outstanding mechanical properties and thermal insulation have attracted significant attention because of their classification as the most advanced and efficient thermal insulation material. However, the complex and environmentally unfriendly preparation technology has consistently hindered the performance improvement and broad practical applications of PBz aerogels. Herein, we report a facile preparation method of PBz aerogels through an aqueous solution system and ambient pressure drying (APD), thereby overcoming the limitations of the conventional methods. The resulting PBz aerogel exhibits lightweight (0.194 g cm −3 ), efficient thermal insulation, low thermal conductivity (0.0313 W m −1 K −1 ), self-extinguishing, super-hydrophobicity (contact angle of 148°), and remarkable mechanical properties. This study proposes a cutting-edge approach to fabricate PBz aerogels, which further amplifies their potential application in the field of thermal insulation.