Theoretical study on the weak interaction and energy performance of nitroformate salts and nitroformate-based propellant formulations

Nitroformate energetic salts are potential high-performance oxidizers which can be used in a solid propellant. The geometric configuration, the weak interaction, and the energy characteristics of hydrazine nitroformate (HNF), ammonium nitroformate (ANF), aminotriazole nitroformate (ATNF), guanidinium nitroformate (GNF), and aminotetrazole nitroformate (ATTNF) were investigated. Analysis results show that there exist hydrogen bonds in all salts except GNF. The binding energies of salt are between 390 and 430 kJ/mol and are positively correlated with densities and thermodynamic stabilities of salts but show reverse trend on impact sensitivities. Binding energy decomposition indicates that the main interaction in anion and cation is electrostatic interaction. The detonation velocity and specific impulse of five nitroformate salts are in the range of 8.6~9.1 km/s and 2200~2600 N s/kg, respectively. Considering the five selected salts as oxidizers, several propellant formulations were designed and the performances of formulations were predicted. The calculation results show that nitroformate salts obviously reduce characteristic signals and improve specific impulse for propellant formulations.