Synthesis and Effects of Two Novel Rare-Earth Energetic Complexes on Thermal Decomposition of Cyclotetramethylene Tetranitramine (HMX)

In order to explore the effect of the energetic complex on the thermal decomposition HMX, two new rare-earth energetic complexes [La(tza)(NO3)(2)(H2O)(4)](n)(1) and [Ce(tza)(NO3)(2)(H2O)(4)](n)(2) (Htza = tetrazole-1-acetic acid) were prepared by a solvent evaporation method. The obtained products were structurally characterized by Fourier-transform infrared spectroscopy (FTIR), elemental analysis, powder X-ray diffraction (PXRD), single crystal X-ray diffraction (XRD), and thermogravimetric analysis coupled with differential scanning calorimetry (TG-DSC). In addition, the compatibility of complex1with cyclotetramethylene tetranitramine (HMX) was studied by DSC and FTIR, respectively. Structural analysis suggested that complex1exhibits an orthorhombic, P 2(1)2(1)2(1)space group, and the La (III) ion was 10-fold coordinated in a distorted double-capped antiprism configuration. Complex2featured a one-dimensional, right-handed helical infinite chain. The effect of complexes1and2on the thermal decomposition of HMX was investigated by DSC, which revealed that complex1showed a slightly better effect than2on the thermal decomposition of HMX and released more heat. Furthermore, complex1had good compatibility with HMX, indicating that it may act as a combustion promoter for nitrate ester plasticized polyether (NEPE) solid propellant.