Synthesis and Properties of Novel Thermally Stable and Insensitive 3,6-dinitropyrazolo[4,3-c]pyrazole-based Energetic Materials

Two novel thermally stable and insensitive 3,6-dinitropyrazolo[4,3-c]pyrazolebased energetic compounds, namely 1,4-bis(2',4',6'-trinitrophenyl)-dinitro[4,3-c]pyrazole (DTNBDNP) and 1,4-bis(2',4'-dinitrophenyl)-3,6-dinitro[4,3-c]pyrazole (DDNBDNP) were firstly reported. DTNBDNP and DDNBDNP were synthesized via the condensation reaction and characterized by nuclear magnetic resonance spectra, infrared spectroscopy, elemental analysis, as well as differential scanning calorimetry (DSC). DTNBDNP and DDNBDNP decompose exothermically at 407.5 ºC and 372.5 ºC, respectively. Based on the densities and calculated heats of formation, the detonation properties were carried out using Gaussian 09 program and Kamlet-Jacobs equations, which were comparable with those of commonly thermally stable energetic materials, such as HNS and TATB. Results showed that polynitro-aromatic substituted 3,6-dinitropyrazolo[4,3-c]pyrazole-based materials had the potential to be useful as new heat-resistant energetic compounds.