Assessment of the thermal stability, catalytic behavior, and laser ignitability of energetic coordination polymer [Cu(HBTT)(H2O)

Abstract

Solvent molecules, especially coordinated solvent molecules, vastly affect the energetic properties of energetic coordination polymers (ECPs). Therefore, an effective strategy to maintain energetic properties is to reduce solvent molecules. In this paper, a nitrogen-rich energetic coordination polymer [Cu(HBTT)(H2O)]n (ECP 1) was synthesized and prepared by integrating the coordination mode. Its properties were adequately investigated, including crystal structure, thermal stability, energetic properties, and sensitivity. In terms of application, it was researched as catalysts for the thermal decomposition of AP and as a primary explosive for laser initiation. As revealed by single-crystal X-ray diffraction results, it crystallizes in and belongs to monoclinic space group P21/n with a 2D layer-like structure. Meanwhile, it has outstanding thermal stability (Tp = 357.2 °C, Ek = 201.78 kJ mol-1) according to differential scanning calorimetry (DSC) curves and thermogravimetric curves (TG). The detonation velocity and detonation pressure of ECP 1 (8.63 km s-1, 36.73 GPa) can bear comparison with RDX and HMX. The catalytic pyrolysis experiment indicates that AP/ECP 1 (10 wt%) can accelerate the thermal decomposition of AP, with the high temperature for decomposition decreasing to nearly 80 °C. The activation energy (Ek) of AP decreased from 217.36 kJ mol-1 to 185.96 kJ mol-1 by adding ECP 1. Meanwhile, ECP 1 has a preliminary response to laser initiation. These results are conducive to the quick development of ECPs.