A novel green electrically controlled solid propellant with good electrical response and high energy performance

Electrically controlled solid propellants (ECSPs) are a new type of propellants with electrically controllable ignition and extinguishment properties. At present, ESCPs are mainly achieved using ammonium nitrate (AN) or hydroxylamine nitrate (HAN) as the oxidant, and thus usually show the disadvantage of low energy performance. In the present work, a novel green ECSP has been designed and prepared using the ammonium dinitramide (ADN) as the main oxidant. For comparison purpose, three propellants were formulated with AN (ECSP-1), ADN (ECSP-2) and the mixture of AN and ADN (ECSP-3) as the oxidant, respectively. The theoretical calculation suggests that the energy of ECSP-3 increases with the increase of the relative content of ADN and the theoretical specific impulse of ECSP-3 reaches 1841.13 N s/kg, 6.5% higher than that of ECSP-1. The combustion performance and circuit characteristics of the propellants were tested with an electric ignition device built in-house. The ignition energy threshold of ECSP-3 is measured to be 516 J, close to the that of ECSP-1. The thermal stability of ECSP-3 is between those of ECSP-1 and ECSP-2. Yet ECSP-3 exhibits the optimal electrical response and high energy performances simultaneously. The gaseous combustion product of ECSP-3 at 25–300 °C was analyzed by continuous infrared spectroscopy and mass spectrometry. The results show that the gaseous product is clean and no harmful gases are found. Finally, according to the experimental results, the combustion mechanism of the prepared propellant was deduced. Our work has provided a new strategy to develop new green high-energy ECSPs.