In this study, few-layered tungsten disulfide (WS2) was prepared using a liquid phase exfoliation (LPE) method, and its thermal catalytic effects on an important kind of energetic salts, dihydroxylammonium-5,5′-bistetrazole-1,1′-diolate (TKX-50), were investigated. Few-layered WS2 nanosheets were obtained successfully from LPE process. And the effects of the catalytic activity of the bulk and few-layered WS2 on the thermal decomposition behavior of TKX-50 were studied by using synchronous thermal analysis (STA). Moreover, the thermal analysis data was analyzed furtherly by using the thermokinetic software AKTS. The results showed the WS2 materials had an intrinsic thermal catalysis performance for TKX-50 thermal decomposition. With the few-layered WS2 added, the initial decomposition temperature and activation energy (Ea) of TKX-50 had been decreased more efficiently. A possible thermal catalysis decomposition mechanism was proposed based on WS2. Two dimensional-layered semiconductor WS2 materials under thermal excitation can promote the primary decomposition of TKX-50 by enhancing the H-transfer progress.

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Thermal decomposition characteristics of benzoyl peroxide (BPO) were preliminary studied by differential scanning calorimetry (DSC), microcalorimeter (C600) and high‐pressure calorimeter (DSC 204 HP). DSC and C600 were used to research the effect of thermal history on the thermal decomposition characteristics of BPO. The time to maximum rate under adiabatic conditions (TMRad) and the self‐accelerating decomposition temperature (SADT) were calculated by combining with the thermal equilibrium equation. The results reveal that the initial decomposition temperature, the highest decomposition temperature and the decomposition completion temperature of BPO increased with the increase of heating rate. The mass scale and thermal history have significant effects on its thermal decomposition. The apparent activation energy of the BPO was calculated by the Kissinger method to be 146.8 kJ mol−1, the apparent activation energy calculated by Friedman method presents that BPO has different apparent activation energy at different stages of the reaction. TD2, TD4, TD8 and TD24 were gained to be 83.5, 80.2, 77.0 and 72.2 °C, respectively. With the increase of the packing quality, the SADT gradually decreased, resulting in a further increased in the risk. To prevent accidents, the initial temperature of BPO should be well governed and massive storage should be avoided.

1,3,3-Trinitroazetidine (TNAZ) has good thermal stability and low shock sensitivity, among other properties, and it has broad prospects in insensitive ammunition applications. In this study, a molecular dynamics calculation based on the ReaxFF-lg force field and multiscale shock technique (MSST) was used to simulate the shock-induced chemical reaction of TNAZ with different shock wave directions. The results showed that the shock sensitivity of TNAZ was in the order of [100] > [010] > [001]. There were significant differences in molecular arrangements in different shock directions, which affected the reaction rate and reaction path in different directions. The molecular arrangement in the [010] and [001] directions formed a “buffer” effect. The formation and cleavage of bonds, formation of small molecules and growth of clusters were analyzed to show the effect of the “buffer”. The polymerization reactions in the [010] and [001] directions appeared later than that in the [100] direction, and the cluster growth in the [010] and [001] directions was slower than that in the [100] direction. In different shock loading directions, the formation and cleavage mechanisms of the N-O bonds of the TNAZ molecules were different, which resulted in differences in the initial reaction path and reaction rate in the three directions

The addition of binders to energetic materials is known to complicate the thermal decomposition process of such materials. To assess this effect, the present work studied the thermal decomposition of cyclotrimethylene trinitramine (RDX)/hydroxy-terminated polybutadiene (HTPB) mixtures and of pure RDX over the temperature range of 2000–3500 K by combining the classical reaction and first-principles molecular dynamics methods. The incorporation of HTPB as a binder was found to significantly reduce the decomposition rate of RDX. At 3500 K, the decay rate constant of RDX in the RDX/HTPB system is 2.0141 × 1012 s–1, while it is 2.7723 × 1012 s–1 in the pure RDX system. However, the binder HTPB had little effect on the initial decomposition mechanism, which involved the rupture of N–NO2 bonds to produce NO2. The HTPB was predicted to undergo dehydrogenation and chain breaking. The free H resulting from these processes was predicted to react with low-molecular-weight intermediates generated by the RDX, resulting in greater equilibrium quantities of the final products H2O and H2 being obtained from the mixed system compared with pure RDX. HTPB-chain fragments were also found to combine with the primary RDX decomposition product NO2 to inhibit the formation of N2 and CO2.