Improved Safety and Loadability of Coated DBX-1

Several additives such as polyvinylpyrrolidone (PVP), polyvinyl butyral (PVB), and ethyl cellulose (EthocelTM) were selected to improve the flowability and safe pressing of copper(I) 5-nitrotetrazolate (DBX-1), a green replacement for lead azide currently under development. These properties are important for pressing the material into small-volume detonators, especially during manufacturing when saving cost, while maximizing efficiency and safety, is critical. Sensitivity tests such as ball drop impact, Bundesanstalt fur Materialprufung (BAM) friction, and electrostatic discharge (ESD) along with compatibility testing and performance testing in M55 stab detonators were conducted. For comparison, all testing was done on both uncoated DBX-1 (control sample) and DBX-1 coated with various additives. DBX-1 coated with PVP and PVB showed better flowability compared to the Ethocel additive. Moreover, a considerable safety improvement during pressing was observed with all coated DBX-1 samples compared to the uncoated control batch; whereas uncoated DBX-1 typically detonates when pressed to 35–40 kpsi, the coated DBX-1 could be pressed to greater than 70 kpsi with no adverse effect. More studies will need to be completed to find a suitable solvent for the safe long-term storage of DBX-1.