Synthesis and Properties of Trinitromethyl-1H-1,2,4-Triazole Bridging Nitropyrazole Energetic Salts

The polynitroazole plays an important role in the design of high-energy density materials. A series of nitrogen-rich salts based on trinitromethyl-substituted 1H-1,2,4-triazole bridging nitropyrazole was prepared. These newly synthesized salts were fully characterized by chemical analysis (infrared, NMR, and mass spectroscopy) as well as experimental tests (thermostability and sensitivities). Their detonation properties (detonation velocity, detonation pressure, etc.) were determined by the EXPLO5 program on the basis of density and heat of formation. These nitrogen-rich salts show moderate thermostabilities and low sensitivities (IS ≥ 10 J, FS ≥ 252 N) due to intermolecular hydrogen bonding interactions. The most promising high-energy insensitive compound is salt 2, which possesses a high density (1.80 g cm⁻³), relatively high thermal stability (149 °C), low sensitivity (IS = 30 J, FS = 252 N), good detonation velocity (8997 m s⁻¹) and detonation pressure (36.7 GPa) which is comparable to cyclotrimethylenetrinitramine (RDX). This study supports the efficiency of utilizing nitrogen-rich salts combined with trinitromethyl-substituted systems in the development of new high-energy, insensitive energetic materials.