From structure to energy: Resorcinol-based benzoxazine polymers for modern ammunition

Today’s ammunition comprises sparingly about 30 wt% of payloads like RDX-based explosive meanwhile, the bulk of the mass consists of structural materials such as metals (e.g., steel and aluminum), which do not contribute energetically. This highlights a significant potential for the improvement of reactive structural materials (RSMs). This class of advanced materials is designed to serve dual purposes: providing structural integrity and releasing chemical energy upon activation. Rigid polymers with glass transition temperature (T g ) higher than the operating temperatures are thought as a new emerging candidate to replace the heavy and metal-based materials (e. g., alloys, thermites). According to this vision, we report the synthesis and characterization of resorcinol-based benzoxazine (Re-Bz) energetic polymer utilizing resorcinol as a renewable material. The assessment of the energetic properties was reported as well. Overall, the newly developed polymer showed promising energetic performances with deflagration temperatures of about 270-275°C, where the combustion heat released during the deflagration was found to be 20.15 kJ·g −1 . The thermal analysis results highlighted that these polymers can be effectively used as reactive structure materials (RSMs) owing to their combination of rigidity above operational temperatures and remarkable energetic performances.