Isoconversional analysis on the non-isothermal decomposition kinetics of high energy oxidizer: Potassium dinitramide (KDN)

The thermal decomposition kinetics of an energetic oxidizer viz., potassium dinitramide (KDN) has been studied by non-isothermal thermogravimetry (TG) technique. The dependence of activation energy (E-a) on conversion (alpha) was evaluated using isoconversional method of Vyazovkin (VYZ). A strong dependence of E-a on alpha was observed, where the mean E-a value of 185.86 kJ/mol was obtained from VYZ. The classical Kissinger method has also been used to calculate the E-a for the decomposition of KDN. Isothermal conversion-time data was predicted from the kinetic parameters derived from the integral isoconversional method of Vyazovkin. The preexponential factor was calculated by a model-free estimate using the kinetic compensation effect. A mechanistic approach for the decomposition of KDN is proposed based on TG-MS studies, Raman spectroscopy and quantitative analysis of the decomposition products.