An experimental and theoretical study on the growth of plate-like β-HMX crystals in the hydroxylated interlayer space

Smart Host-Guest Energetic Material Constructed by Stabilizing Energetic Fuel Hydroxylamine in Lattice Cavity of 2,4,6,8,10,12-Hexanitrohexaazaisowurtzitane Significantly Enhanced the Detonation, Safety, Propulsion, and Combustion Performances

The host-guest inclusion strategy has become a promising method for developing novel high-energy density materials (HEDMs). The selection of functional guest molecules was a strategic project, as it can not only enhance the detonation performance of host explosives but can also modify some of their suboptimal performances. Here, to improve the propulsion and combustion performances of 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (HNIW), a novel energetic-energetic host-guest inclusion explosive was obtained by incorporating energetic rocket fuel, hydroxylamine (HA), into the lattice cavities of HNIW. Based on their perfect space matching, the crystallographic density of HNIW-HA was determined to be 2.00 g/cm³ at 296 K, which has reached the gold standard regarding the density of HEDMs. HNIW-HA also showed higher thermal stability (T_d = 245.9 °C) and safety (H₅₀ = 16.8 cm) and superior detonation velocity (D_V = 9674 m/s) than the ε-HNIW. Additionally, because of the excellent combustion performance of HA, HNIW-HA possessed higher propulsion performances, including combustion speed (S_C = 39.5 mg/s), combustion heat (Q_C = 8661 J/g), and specific impulse (I_sp = 276.4 s), than ε-HNIW. Thus, the host-guest inclusion strategy has potential to surpass the limitations of energy density and suboptimal performances of single explosives and become a strategy for developing multipurpose intermolecular explosives.