Thermal stability assessment of 4-amino-1,2,4-triazole picrate using thermal analysis method

Abstract

4-Amino-1,2,4-triazole picrate (4-ATPA) is synthesized to reduce the corrosiveness of picric acid (PA) to metals, which simultaneously maintains the detonation performance of PA and the advantages of 4-amino-1,2,4-triazole. In this work, the thermal stability of 4-ATPA is estimated using thermogravimetric analysis (TG) and accelerating rate calorimeter. The dynamic TG experimental results suggest that the onset temperature is at the range of 189.0–220.0 °C under different heating rates. The average apparent activation energy of 4-ATPA is 112.0 ± 1.1 kJ mol−1 using Flynn–Wall–Ozawa, Starink, and Kissinger methods based on the multiple heating rates. The isothermal TG experiments indicate that 4-ATPA will be decomposed 10.0% within 1 day if the temperature exceeded 150.7 °C and will be decomposed 10.0% within 10.0 h if the temperature exceeded 162.6 °C. The adiabatic tests depicted that the exothermic reaction initiates at 186.0 °C and a rises sharply at 306.7 °C with the maximum self-heating rate of 4775.5 °C min−1. The exothermic event is accompanied by a pressure rise of 39.7 bar, which confirms the vulnerability of 4-ATPA to undergo catastrophic explosion.