Research on the thermal behavior of novel heat resistance explosive 5,5″-bis(2,4,6-trinitrophenyl)-2,2″-bi(1,3,4-oxadiazole)

5,5′-bis(2,4,6-trinitrophenyl)-2,2′-bi(1,3,4-oxadiazole) (TKX-55) was synthesized through an oxidation-chloridization-condensation-cyclization sequence. Thermal decomposition behavior and non-isothermal decomposition reaction kinetics of TKX-55 were investigated by the differential scanning calorimetry and thermogravimetric analysis (DSC-TG) methods The research of decomposition mechanism of the molecule was further carried out through in-situ FTIR spectroscopy technologies. The experiment results showed that the enlarged conjugated system has a marked effect on the thermal stability and the picryl moiety is much more stable than the 1,3,4-oxadiazole moiety during the heat-up process, indicating that the decomposition process is mostly likely to initiate from the ring-opening reaction of 1,3,4-oxadiazole moiety which is supported by the computational scanning result of potential energy surface.