Physical Characterization of RX-55-AE-5A Formulation of 97.5 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide (LLM-105) and 2.5Viton A

摘要

With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5 % Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, Cp, of ≈ 0.950 J/g·°C, and a thermal conductivity, κ, of ≈ 0.160 W/m·°C. The Lawrence Livermore National Laboratory (LLNL) code Kinetics05 and the Advanced Kinetics and Technology Solutions (AKTS) code Thermokinetics were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E ≈ 180 kJ mol-1 for mass loss in an open pan. Thermal mechanical analysis, TMA, was used to measure the coefficient of thermal expansion, CTE. The CTE for this formulation was calculated to be ≈ 61 μm/m·°C. Impact, spark, friction and evolved gases are also reported.