Construction of Insensitive Energetic Coordination Complexes as Promising Combustion Promoters for Ammonium Perchlorate

Abstract

Herein, a novel energetic ligand, ammonium 2-cyano-2-nitroacetamide (ANCA), was synthesized. Based on this ligand, five new energetic coordination complexes (ECCs-1 to ECCs-5) were prepared using Li+, Na+, K+, Rb+, and Cs+ as the respective metal centers. The crystal structures, thermal stabilities, mechanical sensitivities, and catalytic activities toward the thermal decomposition of AP were systematically investigated. The densities of these complexes range from 1.573 to 2.643 g·cm–3, increasing with the atomic number of the metal center. All complexes exhibit excellent thermal stability, with decomposition temperatures ranging from 237 to 253 °C, and are insensitive to mechanical stimuli, with impact sensitivities exceeding 40 J and friction sensitivities exceeding 360 N. Notably, ECCs-3 demonstrated the best catalytic performance toward the thermal decomposition of AP, reducing the high-temperature decomposition peak temperature by 129 °C. Ignition tests further confirmed that the ECCs-3, ECCs-4, and ECCs-5 formulations exhibited excellent combustion behavior, with ECCs-5 producing the brightest flame. These results indicate that the as-prepared insensitive energetic coordination complexes are promising multifunctional combustion promoters for solid propellants.