Detonation Performance of Ten Forms of 5,5′-Dinitro‑2H,2H′‑3,3′-bi-1,2,4-triazole (DNBT)

Hydrate formation is a common mechanism by which the energetic performance of explosives can be degraded; the reason for this performance reduction has been difficult to tie to any physical parameter because typically only one solvate of a given energetic is known. A deep investigation into the effects of hydration and density on detonation performance is presented here, made possible by the discovery of numerous crystalline forms of the energetic 5,5′-dinitro-2H,2H′-3,3′-bi-1,2,4-triazole (DNBT). The detonation velocities and pressures of DNBT and its hydrates are reported and compared, revealing that the primary way in which hydration depresses detonation velocity and pressure is through a decrease in crystallographic density. The specific impulses for DNBT and its hydrates are also reported and indicate that hydration decreases the specific impulse by diluting the propellant with molecules that do not productively contribute to energy release. In order to produce a high-performing phase-pure form of DNBT, a hydrogen peroxide hemisolvate of DNBT was crystallized and characterized. The hydrogen peroxide solvate of DNBT was produced without significant inclusion of water, demonstrating that crystallization of structurally related hydrogen peroxide solvates is an effective strategy for improving the energetic performance and ease of phase purification for materials that are prone to forming hydrates.