Investigating the interaction and reactivity of the admixture of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, 3-nitro-1,2,4-triazol-5-one, and aluminium with polyester-based polyurethanes: an analysis of chemical compatibility and thermal decomposition kinetics

The potential of aluminized energetic composites to enhance blast performance through chemical interactions with the detonation products of energetic compounds and aluminum makes them a subject of significant interest for defense applications. This research investigates a mixture comprising 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), 3-nitro-1,2,4-triazol-5-one (NTO), aluminum powder (Al), and a polyester-based polyurethane (PU) binder system cured with different curing agents. The study analyzes the reactivity, kinetic and thermodynamic parameters related to non-isothermal thermal decomposition, employing thermal analytical techniques. The study of chemical compatibility was performed via vacuum stability tests (VST) and differential scanning calorimetry (DSC), following the protocols outlined in the standardization of agreement (STANAG 4147). Experimental outcomes demonstrate that the admixture of CL-20, NTO, and Al is compatible with polyurethane (PU)-containing various curing agents. The kinetics of thermal decomposition was studied utilizing the Ozawa method, the Kissinger method, and the American Society for Testing and Materials (ASTM) kinetic E-698 method. The data obtained through different experimental methods corroborated that the thermal reactivity of CL-20 is effectively retained in the admixture. The high thermal stability was ascribed to a non-spontaneous process, as demonstrated by the positive activation Gibbs free energy and enthalpy values.