New ligands and energetic coordination compounds for use as primary and laser ignitable explosives

摘要

The reliable but highly harmful compounds lead azide and lead styphnate still dominate the field of primary explosives being applied in most ignition and initiation systems to this day. Therefore, an extensive investigation into energetic materials led to the very promising strategy of developing energetic coordination compounds (ECC) with similar performance and minimized toxicity. Energetic coordination compounds can easily be tuned toward their resulting performance and sensitivities by varying the metal center, the ligand system, and the corresponding anion. In the present study, the new ligands I-(2-azidoethyl-5H-tetrazole) and l-(3-azidopropyl-5H-tetrazole), were coordinated to different metal centers (e.g. Fe~(2+), Cu~(2+), Ag+) and compared to each other. The ligands were synthesized starting from 2-chloroethyl-1-ammonium chloride and the corresponding propyl derivative. In addition, the ligands 1- and 2-amino-5H-tetrazole as well as 1- and 2-amino-5-methyl-tetrazole were applied and several highly energetic complexes characterized. Furthermore, the influence of the additional methyl group on the coordination sphere and the resulting difference of the energetic properties were investigated. Characterization includes XRD, IR, EA, DTA and sensitivity (impact, friction, and ESD) measurements as well as for selected compounds classical initiation tests (nitropenta filled detonators). Laser irradiation of the received primary explosives with near-infrared light (NIR) led to a reliable and safe ignition and expands their potential for future applications.