Abstract: The decomposition reaction kinetics of the double-base (DB) rocket propellant composed of the mixed ester of triethyleneglycol dinitrate (TEGDN) and nitroglycerin (NG), and nitrocellulose (NC) with lanthanumcitrate as a combustion catalyst was investigated by thermogravimetry and differential thermogravimetry (TG-DTG), and differential scanning calorimetry (DSC) under atmospheric pressure and flowing nitrogen gas conditions. The results showed that the thermal decomposition processes of DB propellant had two mass loss stages: volatilization and decomposition of the mixed ester in the first-stage and exothermic decomposition reaction in the second-stage. The exothermic decomposition reaction mechanism obeyed the third-order chemical reaction rule. The kinetic parameters of the reaction were: Ea=231.14 kJ·mol-1, A=10^23.29 s-1. The kinetic equation can be expressed as: dα/dt=^₁₀22.99(1-α)3e^-2.78×104/T. The critical temperatures of the thermal explosion of the DB propellant obtained from the onset temperature (Te) and the peak temperature (Tp) were: Tbe=463.62 K, Tbp=477.88 K. The entropy of activation (⊿S^≠), enthalpy of activation (⊿H^≠), and free energy of activation (⊿G^≠) of the reaction were 219.75 J·mol-1·K-1, 239.23 kJ·mol-1, and 135.96 kJ·mol-1, respectively.

Key words: Double-base propellant, Nonisothermal kinetics, Lanthanumcitrate, Combustion catalyst, Triethyleneglycol dinitrate, Nitroglycerin