Unraveling the characteristics and pyrolysis mechanism of diethylene glycol dinitrate plasticized nitrocellulose supplemented with organic stabilizers

The current work examined the properties and thermal decomposition mechanism of a double-base propellant comprising nitrocellulose (NC), diethylene glycol dinitrate (DEGDN), and organic stabilizers. To achieve this objective, a comprehensive analysis was conducted on the influence of stabilizers, namely 2-nitrodiphenylamine (2-NDPA), 1,3-dimethyl-1,3-diphenylurea (MC), and kraft lignin, on the characteristics and pyrolysis gases of NC/DEGDN. Experimental findings demonstrated that kraft lignin has a good stabilizing efficiency, similar to that of 2-NDPA and MC stabilizers. Moreover, differential scanning calorimetry (DSC) experiments revealed that the incorporation of MC, 2-NDPA, and Kraft lignin has increased the maximum peak temperature of the main thermolysis process from T_peak = 192.1 °C for NC/DEGDN baseline to T_peak = 194.5 °C for NC/DEGDN/MC, T_peak = 193.3 °C for NC/DEGDN/2-NDPA, and T_peak = 194.3 °C for NC/DEGDN/Kraft lignin. In addition, differences in the stabilization mechanism for each stabilizer were examined using thermogravimetry connected to an infrared spectroscopy (TGA-FTIR). The obtained findings highlighted the discernible influence of stabilizer types on the gaseous products of NC/DEGDN propellant, particularly elucidating their effects on the intensity and type of nitrogen oxides generated throughout the pyrolysis process.