Thermoanalytical study of the pesticide 3-amino-1,2,4-triazole (ATA) has been carried out, using simultaneous DTA-TG in nitrogen
flow, in order to know its thermal behaviour and stability. These techniques have been further complemented using evolved
gas analysis and mass spectroscopy (EGA-MS). Two different stages of ATA decomposition were observed: after the first decomposition
step, a mixture of compounds is obtained, according to MS data, being the principal component a compound of molecular weight
126. It is formed by a first order reaction mechanism, according to the kinetic study, withEa=124±8 kJ·mol−1. The second decomposition step takes place about 735°C, with evolution of HCN and NH3, being the final weight loss 96%.