Preparation and Properties of the Lowest Eutectic Mixture of DNAN/2,4-MDNI

The eutectic strategy offers an effective route to tailor the melting point and energy content of melt-cast explosive carriers. Herein, a novel binary eutectic system composed of 2,4-dinitroanisole (DNAN) and 1-methyl-2,4-dinitroimidazole (2,4-MDNI) is reported. Mixtures with varying DNAN/2,4-MDNI mass ratios were prepared by solvent evaporation. The temperature-composition (T-x) phase diagram constructed from differential scanning calorimetry (DSC) measurements revealed a eutectic composition at a DNAN:2,4-MDNI mass ratio of 70:30, corresponding to a eutectic temperature of 72.71 °C. Structural and morphological characterization confirmed that the eutectic constitutes a physical mixture without chemical reaction or polymorphic transition. Thermal analysis indicated a decomposition peak temperature of 332.09 °C, demonstrating satisfactory thermal stability, while isothermal thermogravimetric measurements showed that the eutectic reduced the volatilization of DNAN. Microcalorimetry revealed a supercooling degree of 28.31 °C for the eutectic, which was reduced to approximately 11 °C upon incorporation of HMX and RDX. Furthermore, the eutectic exhibits a friction sensitivity of 168 N, an impact sensitivity exceeding 40 J, and a detonation velocity of 6506 m·s -1 , representing an 8.9% improvement over pure DNAN. These characteristics demonstrate that the DNAN/2,4-MDNI eutectic system integrates a low melting point, favorable safety, and enhanced energy output, underscoring its promising potential for melt-cast explosive carrier applications.