Modification of N-methyl group toward new energetic melt-castable material with good energy-stability balance

The energy and stability properties of energetic materials are often contradictory to each other (e.g. high energy vs low thermal stability). There is no doubt that it is still a challenge to explore the effective balance between energetic performance and molecular stability, especially for melt-castable materials. In this study, we selected the 4-methoxy-3,5-dinitropyrazole framework and stable nitro group to design a new energetic melt-castable compound, namely 4-methoxy-3,5-dinitro-1-(nitromethyl)-1H-pyrazole (MDNNMP). Compared with the N-methylation product DMDNP and nitrato-substituted derivative MC-7, MDNNMP exhibits better balanced performance including good thermal stability (Td: 203.7 °C), detonation velocity (Dv: 8099 m s-1) and impact sensitivity (20 J). The favorable balanced performance of MDNNMP suggests it as a suitable candidate for high-performance melt-castable material. Additionally, compared with the nitrato-methyl group, the nitromethyl group demonstrated superior advantages in performance regulation.