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Abstract: The thermal decomposition process of a newly designed composite material KClO3–RDX (KC-RDX) was investigated by combined TG–DSC–FTIR technique and DSC technique. It was shown that KC-RDX began to decompose at about 209.9°C after melting, and the fast stage of mass loss at the temperature range of 209.9–259.8°C is considered to be the result of the thermolysis and complex reactions of KClO3 and RDX with energy release of 1887Jg−1, which exceeded that of pure RDX about 10%. The CO, CO2, HCN, NO2 and H2O were detected as the main gaseous products of KC-RDX decomposition, and occurred in initial stage of RDX decomposition are greatly affected by KClO3. In contrast to pure RDX, there was nearly no CH2O detected in thermolysis products of KC-RDX. In the presence of electronegative oxygen radical produced by thermolysis of KClO3 oxidized CH2O through gas-phase reaction CH2O+O2 →HCO+HO2, which might be one of the unique chemical reaction for KC-RDX. [Copyright &y& Elsevier]

The 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) is considered as the most promising energetic materials (EMs) in terms of its detonation performance. Nonetheless, its applications are limited due to high sensitivity and low phase stability. Thermal decomposition behavior especially for the initial reaction pathway determines its reactivity and sensitivity. An in-depth discernment of the innate decomposition pathways of CL-20 would facilitate the precision tailoring and augmentation of its performance. The thermal behavior and decomposition mechanisms of CL-20 are largely dependent on the experimental conditions and chemical environments. In this brief review, the effects of those factors on the thermal decomposition mechanisms of CL-20 are summarized from both theoretical and experimental perspectives. In particular, the interaction mechanisms between CL-20 and the other commonly used energetic compounds are simultaneously elucidated. • Environmental conditions and contact materials influence the thermal decomposition mechanism of CL-20. • High temperatures can weaken the influence of physical factors on the decomposition of CL-20. • The influence of contact materials on the decomposition mechanism of CL-20 varies depending on the material used. • Need to strengthen theoretical research on the decomposition mechanism of CL-20 under chemical environments. [ABSTRACT FROM AUTHOR]

The two-dimensional energetic polymer triaminoguanidine–glyoxal (TAGP) has been used in modification of EMs to formation of various hybrid materials for higher density and better stability due to its excellent capability to desensitize high energetic crystals without any energy loss. In this paper, theoretical calculations based on ReaxFF-MD were performed to demonstrate the thermal decomposition mechanisms of TAGP, which has been further proved by experimental results from Pyro-GC/MS analysis. The results show that there are three dominant pathways for the initial decomposition of TAGP, i.e. , the breakage of C-N bond with production of C 2 H 3 ON 2 (most likely to happen), the scission of N-N bond with release of C 2 H 2 ON, and the rupture of N-N bond accompanied with the proton transfer to release C 2 H 3 ON. Therefore, the C 2 H 3 ON 2 , C 2 H 2 ON and C 2 H 3 ON are the dominant initial decomposition products of TAGP, which may gradually transform to the final gaseous products. The experimental results confirmed the presences of these substances. The major final gaseous products of TAGP include N 2 , H 2 , H 2 O, NH 3 , NH 4 , NH 2 , N 2 H, N 2 H 2 , HCN and CO 2 , among which the concentration of N 2 is the highest, relatively higher than H 2 , H 2 O and NH 3. Besides, the initial decomposition rate of TAGP largely depends on its MW. The activation energies for formation of C 2 H 3 ON 2 and N 2 under isothermal conditions has been obtained to further illustrate the effect of MW on the decomposition rate. • Three types of typical TAGP structural models have been constructed according to the measured molecular weights. • The detailed decomposition mechanisms of TAGP have been proposed. • Their final thermolysis products have been mutually confirmed by ReaxFF-MD simulations and Pyro-GC/MS experiments. [ABSTRACT FROM AUTHOR]

Highlights: [•] DHDNEBa was firstly synthesized by the process of metathesis reaction with a yield of 95.7%. [•] The most probable kinetic model function of the exothermic decomposition reaction was deduced. [•] ΔS ≠, ΔH ≠,ΔG ≠, T SADT and T b of DHDNEBa were investigated. [•] The thermal decomposition mechanism of DHDNEBa was studied by means of thermolysis/RSFTIR and TG–MS technologies. [ABSTRACT FROM AUTHOR]