Bis-oxadiazole, or more formally known as bis(1,2,4-oxadiazole)bis(methylene) dinitrate, is a nitrated heterocyclic compound of the oxadiazole family.[1]
Bis-oxadiazole is related to bis-isoxazole tetranitrate (BITN), which was developed at the United States Army Research Laboratory (ARL). With a high nitrogen content, these compounds are poised to release a large volume of very stable N2.[2] It is a “melt-cast” explosive material that is potentially both more powerful and environmentally friendly alternative to TNT.[3]
Glyoxal condenses with hydroxylamine to yield diaminoglyoxime (DAG). Treating DAG with methyl glycolate in the presence of base at high temperature yields bis(1,2,4-oxadiazole).[4]
TNT is attractive explosive because it is a melt-castable. A low melting point of about 80 °C and high decomposition temperature of 295 °C allows manufacturers to safely pour TNT into molds. The production of TNT generates hazardous waste, e.g. red water and pink water.
Bis-oxadiazole, which is also melt-castable, is about 1.5 times more powerful than TNT and yet produces less hazardous wastes.
Onset temperature of melting | 84.5 °C | 80.4 °C | |
Onset temperature of decomposition | 183.4 °C | 295.0 °C | |
Derived density from X-ray data | 1.832 g cm−3 | 1.65 g cm−3 | |
Detonation pressure | 29.4 GPa | 20.5 GPa | |
Detonation velocity | 8180 m s−1 | 6950 m s−1 | |
Molar enthalpy of formation | -79.4 kJ mol−1 | -59.3 kJ mol−1 |