Bespoke HMX/Nitrocellulose Co-crystal with Synergistic Thermal Decomposition Kinetics

Abstract Whereas NC is an efficient energetic binder; HMX is one of the most potent energetic materials. Integration of HMX into NC binder can offer novel synergistic effect with superior decomposition kinetics. NC could initiate decomposition at low temperature with the release of reactive nitrogen oxide species that could alter HMX decomposition from C–N bond cleavage to hydrogen atom abstraction. HMX/NC co-crystal was developed via novel electrostatic hydrogen attraction. XRD diffractogram demonstrated the evolution of novel co-crystalline structure that differ from its main constituents with characteristic peak at 2Ɵ = 72°; this peak could be ascribed to the strong hydrogen bonding between NC hydroxyl group and HMX nitro group. SEM micrographs confirmed the uniform dispersion of HMX particles into NC fibrous structure. The developed co-crystal revealed novel thermal behaviour with superior decomposition enthalpy, higher than NC and HMX by 73, and 94% respectively. Co-crystal provided main decomposition temperature at 200 °C compared with 208 °C, and 285 °C for NC, and HMX respectively. HMX/NC co-crystal displayed reaction propagation index of 10.5 compared with 3.6 and 5.6 for HMX and NC respectively. HMX/NC co-crystal exhibited decrease in apparent activation energy by − 6.2 and − 21.4% for HMX and NC respectively, using Kissinger and KAS models. This manuscript shaded the light on facile development of novel energetic composites via synergism of its main components.