New explosive compounds that are less sensitive to shock and high temperatures are being tested as replacements for TNT and RDX. Two of these explosives, DNAN (2,4-dinitroanisole) and NTO (3-nitro-1,2,4-triazol-5one), have good detonation characteristics and are the main ingredients in a suite of insensitive munitions (IM) explosives that are being, or soon will be, fielded. Both compounds, however, are more soluble than either TNT or RDX; and research has shown that both have some human and environmental toxicity. Data on their fate is needed to determine if DNAN and NTO have the potential to reach groundwater and be transported off base, an outcome that could create future contamination problems on military training ranges and trigger regulatory action. In this study, we measured how quickly DNAN and NTO dissolve in IM formulations and how solutions of these IM explosives interact with different types of soils. Because both dissolution and solution-soil interactions are determined by a suite of parameters, we are using a multifaceted approach to studying these processes. Given a mass of IM compounds scattered on the range, our work will help determine the dissolved IM masses, their subsequent transport and fate, and their likelihood of reaching groundwater. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

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Tricresyl phosphate (TCP) forms protective films on moving mechanical components through thermally driven decomposition and interactions with the ferrous surfaces of the components. These reactions are hidden from view in moving interfaces, but are known to be sensitive to both the surface material and the isomeric form of the TCP. Here, temperature-programmed reaction spectroscopy (TPRS) and gas chromatography-mass spectroscopy (GC-MS) are complemented by reactive molecular dynamics (MD) simulations to investigate the thermal decomposition of meta and para isomers of TCP reacting with ferrous materials. Key observations are that the primary decomposition product of TCP is cresol, more cresol is generated on Fe 2 O 3 than on Fe 3 O 4 , and that para-TCP isomers are more reactive than meta-TCP isomers. These trends are explained using the simulations to identify multiple reaction pathways leading to cresol formation. The likelihood of each pathway is quantified and correlated to surface material and TCP isomer trends in terms of energy barriers for the rate-limiting steps in the decomposition reactions.

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Fourier transform Raman (FTR) spectroscopy employing near-IR laser radiation at 1.06 pm as the scattering source was used to obtain Raman spectra of some neat energetic materials and several propellant formulations containing those energetic materials. It is shown that only crystalline components of propellant formulations are easily detected by FTR spectroscopy. Also, FTR spectroscopy is shown to be a useful tool in determining the principle ingredient@) in many non-colored propellant formulations.