Solubility Report of 1-Methyl-3,5-Dinitro-1H-1,2,4-Triazole (MDNT) and 2-Methyl-4,5-Dinitro-2H-1,2,3-Triazole 1-Oxide (MDNTO) for Co-Crystallization Screen.

摘要

Solubilities of 1-methyl-3,5-dinitro-1H-1,2,4-triazole (MDNT) and 2-methyl-4,5-dinitro-2H-1,2,3-triazole 1-oxide (MDNTO) in a range of organic solvents were studied in an Avantium Crystal16(trademark) parallel crystallizer in preparation for co-crystallization screening of these energetic melt-cast materials. Solubility curves were constructed by evaluating the turbidity of solutions through a range of temperatures. Concentration versus temperature plots showed models with R2 values ranging from 0.8464 to 0.9947. Most model fits were linear in nature with the exception of MDNT in methanol which exhibits two distinct regions of solubility, first linear to a temperature of approximately 42 degrees C, followed by an exponential region from 40 degrees to 60 degrees C. Nuclear magnetic resonance studies were conducted in an effort to determine the cause of this change. Unfortunately, variable temperature studies of both 1H and 13C of MDNT in deuterated methanol yielded no evidence of a change in structure at elevated temperatures. Further research is required to determine the cause of the distinct change in MDNT solubility in methanol. The resulting solubility data was also converted to van't Hoff plots which can be used to interpolate or extrapolate the component solubilities at alternate temperatures.