CL-20 analogues: Structure - Thermal stability/decomposition mechanism relationships

Abstract

Absracts: The thermal decomposition of a number of analogues of hexanitrohexaazaisowurtzitan (CL-20), in where one or more N-nitro groups have been replaced by another explosophoric unit (diverse N-alkylnitramine groups or N- trinitroethyl), has been studied by methods of isothermal and non-isothermal kinetics. It was found that replacing the N-nitro group with even a more thermally stable substituent leads to a decrease in the stability of the nitrated hexaazaisowurtzitane framework. It was suggested that the substituent distorts the symmetry of the strained hexaazaisowurtzitane cage, which affects the strength of the N–NO2 bond. When a substituent less stable than the N-nitro group in the parent CL-20 is installed, the initial stage of degradation is determined by the decomposition kinetics of this substituent. One of the objects of this study, 4,10-dinitro-2,6,8,12-tetrakis (2,2,2-trinitroethyl) −2,4,6,8,10,12-hexaazaisowurtzitane (8), was synthesized for the first time; it was fully characterized and also confirmed by X-ray structural data.

Keywords

• Thermal decomposition
• Energetic materials
• Alkylnitramine-functionalized pentanitro hexaazaisowurtzitanes
• 4,10-Dinitro-2,6,8,12-tetrakis(2,2,2-trinitroethyl)-2,4,6,8,10,12-hexaazaisowurtzitane