Synthesis, Performance, and Thermal Behavior of Two Insensitive 3,4-Dinitropyrazole-Based Energetic Cocrystals
Qamar‐un‐Nisa Tariq, Yufan Bi, Saira Manzoor, Maher‐un‐Nisa Tariq, Wenli Cao, Wen‐Shuai Dong, Jianguo Zhang
Abstract
Due to the acidity and the limited applications of 3,4-dinitropyrazole (DNP), two types of nitrogen-rich energetic cocrystals (DD1 and DD2) based on DNP and 3,4-diaminofurazan (DAF) were synthesized. The magnificently grown cocrystals were thoroughly examined by Fourier transform infrared spectroscopy, powder X-ray diffraction, single-crystal X-ray diffraction, elemental analysis, and nuclear magnetic resonance. A differential scanning calorimetry analysis revealed that both cocrystals have different endothermic peaks and remarkably similar exothermic peaks. Moreover, thermogravimetric analysis demonstrates that the thermal decomposition of DD1 and DD2 seems to be three mass loss stages. Hirshfeld surface analysis suggests that O···H (hydrogen bonding) close contacts contribute the most to the stabilization of DD1 and DD2. Subsequently, the pH values of DD1 and DD2 indicate that cocrystals reduce the acidity of DNP; additionally, the inclusion of hydrogen peroxide can improve the oxygen balance of the cocrystal to a certain degree. The obtained cocrystals have high nitrogen contents and acceptable sensitivities to external stimuli (friction and impact) that prove them as promising candidates for expanding the applications of DNP in the field of energetic materials after overcoming an acidity problem.