Molecular Dynamic Simulation of Melting Points of Trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadacalin (TNAD) with Some Propellants

Molecular dynamic simulation was employed to predict the melting points Tm of TNAD/HMX, TNAD/RDX, TNAD/DINA, and TNAD/DNP systems (tans-1,4,5,8-tetranitro-1,4,5,8-tetraazadacalin (TNAD), dinitropiperazine (DNP), cyclotetramethylenete-tranitroamine (HMX), cyclotrimethylenetrinitramine (RDX), and N-nitrodihydroxyethy-laminedinitrate (DINA)). Tm was determined from the inflexion point on the curve of mean specific volume vs. temperature. The result shows that the Tm values of TNAD/HMX, TNAD/RDX, and TNAD/DINA systems are 500, 536, and 488 K, respectively. The TNAD/DNP system has no obvious Tm value, which shows the system is insoluble. Us-ing Tm, the solubility of the four systems was analyzed. The radial distribution functions of the four systems were analyzed and the main intermolecular forces between TNAD and other energetic components are short-range interactions. The better the solubility is, the stronger the intermolecular interaction is. In addition, the force field energy at different temperature was also analyzed to predict Tm of the four systems.