Rapidly Degradable Pyrotechnic System

Abstract : In this SERDP proof-of-concept project, Infoscitex established feasibility of using enzymatic approaches to develop a rapidly degradable, environmentally benign, pyrotechnic system. Training grounds and battlefields are being polluted by the remains/debris of detonated/fired or, in some cases, unexploded pyrotechnic devices. The most abundant source of pollution comes from the outer casing-housing that is usually constructed from aluminum or steel protected by a corrosion resistant coating containing hexavalent chromium and cadmium. Adverse environmental and health affects are associated with these coatings. Decommissioning training fields contaminated with pyrotechnic debris requires significant cleanup and remediation. The focus of this SERDP effort was to develop biocatalyst for hydrolysis of certain liquid crystalline polymers (LCP); thus these polymers could be used as a replacement for metal castings. The program encompassed three main activities: (1) Generation of a microbial strain that would be able to produce LCP degrading enzymes; (2) Trial LCP hydrolysis with the LCP degrading enzymes; (3) Estimating the degree of LCP degradation. The outcomes of the Phase I activities included the following: (1) Several E. coli clones capable of elevated production of hydrolases active on the LCP-like structures were generated using genetic engineering; (2) The E. coli clone culture supernatants were evaluated for LCP degradation. No TLCP mass loss was observed with these clones; (3) Some deterioration of the mechanical properties of the selected LCP was observed at 50 deg C and using supernatants of Thermobifida cultures; (3) No deterioration of the TLCP mechanical properties was observed during the experiments performed at ambient temperatures using supernatants of Thermobifida cultures.