A promising TNT alternative 3,3′-bi(1,2,4-oxadiazole)-5,5′-diylbis(methylene)dinitrate (BOM): thermal behaviors and eutectic characteristics

Abstract

3,3′-Bi(1,2,4-oxadiazole)-5,5′-diylbis(methylene)dinitrate (BOM) is a liquid phase carrier for melt cast explosives that is expected to replace TNT. The combination of a conjugated 1,2,4-oxadiazole backbone and nitrate ester groups endows BOM with both good energetic performance and impressive insensitivity. In this paper, the thermal behaviors of BOM were investigated using a TG–DSC synchronous thermal analyzer, proving that BOM is basically non-volatile under heating and melting processes. The apparent activation energy of BOM calculated by the Kissinger method was 158.2 kJ mol⁻¹ at atmospheric pressure, which is higher than that of DNTF at atmospheric pressure and TNT at 2 MPa, indicating good thermal stability at low temperatures. The thermal decomposition mechanism of BOM was studied through both DSC-MS and in situ FTIR technologies. The low eutectic characteristics of BOM and DNTF were also investigated carefully and the best ratio of BOM/DNTF was 40/60 with a melting point at 75.5 °C. Finally, the detonation performances of TNT/HMX, BOM/HMX and BOM/DNTF(40/60)/HMX explosive formulations were calculated, showing that the detonation performances of the latter two formulations were significantly higher than that of TNT/HMX.