The interface interaction and thermal sensitivity of nitrogen-rich energetic co-particles: A reactive molecular dynamics simulation study

Abstract

Composite explosives are the ultimate used form of energetic materials in weapon systems and aerospace or deep-sea explorers. Among them, the energetic co-particles which combine high-energy crystals with low-sensitivity energetic crystals, is a excellent way to balance energy and safety for energetic materials. In this work, a kind of nitrogen-rich octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX) / 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) co-particles were investigated using molecular modeling methods. Different ratios of HMX/LLM-105 co-particles were constructed by combining different high-energy HMX surfaces with low-sensitivity LLM-105 surfaces. Reactive molecular dynamics simulations (RMD) were carried out on the co-particle models to investigate the thermal sensitivity, as well as classical molecular dynamics simulations were performed to investigate the interfacial interactions. The results show that strong attractive forces including van der Waals and electrostatic interactions exist along the crystalline interfaces, and the thermal decomposition reactions were greatly influenced by the composition of the co-particles. Finally, recommended ratio of HMX/LLM-105, which has enough attractive interaction to enhance the interface, high energy as well as good thermal stability was selected. This research is of significance on the design of advanced insensitive energetic composites.