Insights into Catalytic Mechanism of 4MgCO_3·Mg(OH)_2·5H_2O on Thermal Kinetics and Combustion Behavior of 5-amino-1h-tetrazole Based Propellant

摘要

The mass ratio effect of 4MgCO_3·Mg(OH)_2·5H_2O addition on the catalytic activity for 5AT-Sr(NO_3)_2 propellant is studied by performing a detailed thermogravimetry and differential scanning calorimetry analysis (TG-DSC) kinetic analysis, a Fourier transform infrared (FTIR) spectrometer analysis, and combustion characteristic parameters measurement. The presence of 4MgCO_3·Mg(OH)_2·5H_2O is found to decrease the characteristic decomposition temperatures (T_0, T_e, and T_p), reduce the net decomposition enthalpy, and reduce the apparent activation energy, indicating that the 5AT-Sr(NO_3)_2 propellant catalyzed by 4MgCO_3-Mg(OH)_2-5H_2O is a kind of heat sensitive compound and needs more attention during storage period. Burning tests show that with the 4MgCO_3·Mg(OH)_2·5H_2O addition, all the burning rate, pressure exponent, and outlet temperature of 5AT-Sr(NO_3)_2 based propellant are reduced dramatically. Therein, the catalytic effect of 20 wt. % 4MgCO_3·Mg(OH)_2-5H_2O turns out to be superior than 10 wt. %, accompanied by the smaller pressure exponent less than one as well as the lower outlet temperature. These findings will contribute to the application of 5AT-Sr(NO_3)_2 propellant in SPGG fire-fighting technology, promoting the development and application of SPGG in aviation areas.