In order to obtain a better understanding of the pyrolysis mechanism of urazole, molecular orbital (MO) calculations and evolved
gas analysis were carried out. The MO calculations were performed using the density functional method (B3LYP) at the 6-311++G(d,p)
levels by Gaussian 03. The geometrical structure of urazole and its tautomers were examined theoretically. Identification
and real-time analysis of the gases evolved from urazole were carried out with thermogravimetry-infrared spectroscopy (TG-IR)
and thermogravimetry-mass spectrometry (TG-MS). The evolved gases were identified as HNCO, N2, NH3, CO2, and N2O at 400 °C, but were different at other temperatures.