Further towards the fast, continuous, efficient and scaled-up production of energetic cocrystals, a microchannel-confined crystallization strategy has been developed to prepare a high-quality CL-20/HMX cocrystal with desired shape and size. Applying the flow-focusing microchannel, the mixing efficiency of solution and antisolvent and supersaturation were facilely regulated through changing the solution concentration and flow rate ratio of the solution and antisolvent. At the solution concentration of 0.25 mol L⁻¹ and flow rate ratio of 1 : 6, a pure CL-20/HMX cocrystal with a cube-shaped appearance and a particle diameter D (4, 3) of 21.8 μm has been obtained, overcoming the problem easy to crystallize in platelet morphology. This cocrystal presents a sharp decomposition within a very narrow temperature range (245.1 °C to 246.2 °C) and a peak temperature of 245.4 °C, close to that of raw CL-20, showing a quick energy release rate. TG-FTIR and thermal analysis illustrate that its thermal behavior under isothermal conditions is determined by the decomposition of the least stable CL-20 molecules. A high density of 1.9552 ± 0.0014 g cm⁻³ at room temperature, few internal defects and friction impact sensitivity, even lower than that of raw HMX, mean high crystal quality of the CL-20/HMX cocrystal.

Herein, in order to design the formulation of fluoropolymer bonded explosives, common fluoropolymers were selected and added to the high energy density compound hexanitrohexaazaisowurtzitane (ε-CL-20). Molecular dynamics simulations were carried out on fluoropolymers (F2603, F2311, F2314, F2426, and PTFE) and fluoropolymers bonded ε-CL-20. Glass transition temperature (Tg) of fluoropolymers were calculated. Besides, the mechanical properties and physical compatibilities of ε-CL-20 based polymer bonded explosives were predicted. The calculated results show that the order of Tg of fluoropolymers is: PTFE > F2314 > F2311 > F2462 ≈ F2603 and Tg of F2603 increases as the degree of polymerization increases. The binding energy for fluoropolymers with ε-CL-20 is in the following order: ε-CL-20/F2462 > ε-CL-20/F2603 > ε-CL-20/F2314 > ε-CL-20/F2311. All fluoropolymers interact with ε-CL-20 mainly in vdW force. The order of tensile modulues is: ε-CL-20 > ε-CL-20/F2314 > ε-CL-20/F2311 > ε-CL-20/F2462 > ε-CL-20/F2603, the orders of Poisson’s ration (γ) and the quotient bulk modulus (K)/shear modulus (G) are opposite.

In order to explore the mechanism of reaction involving Al-polytetrafluoroethylene (PTFE) mechanically activated energetic composites, a molecular dynamics simulation was carried out to predict the pyrolysis of PTFE. Then, density functional theory (DFT) was applied to calculate the mechanism of reaction between the products of PTFE pyrolysis and Al. Furthermore, the pressure and temperature obtained during the reaction of Al–PTFE were tested to study the chemical structure before and after heating. Finally, the laser-induced breakdown spectroscopy experiment was performed. According to the experimental results, the main pyrolysis products of PTFE include F, CF, CF₂, CF₃ and C. The path of the CF₃ + Al → CF₂ + AlF reaction is the easiest to achieve. AlF₃, Al and Al₂O₃ are the main components of the pyrolysis products of PTFE with Al. Compared with Al–PTFE, the ignition temperature required by the Al–PTFE mechanically activated energetic composite is lower and its combustion reaction is faster.

The external electric field (E-field), which is an important stimulus, can change the decomposition mechanism and sensitivity of energetic materials. As a result, understanding the response of energetic materials to external E-fields is critical for their safe use. Motivated by recent experiments and theories, the two-dimensional infrared (2D IR) spectra of 3,4-bis (3-nitrofurazan-4-yl) furoxan (DNTF), which has a high energy, a low melting point, and comprehensive properties, were theoretically investigated. Cross-peaks were observed in 2D IR spectra under different E-fields, which demonstrated an intermolecular vibration energy transfer; the furazan ring vibration was found to play an important role in the analysis of vibration energy distribution and was extended over several DNTF molecules. Measurements of the non-covalent interactions, with the support of the 2D IR spectra, indicated that there were obvious non-covalent interactions among different DNTF molecules, which resulted from the conjugation of the furoxan ring and the furazan ring; the direction of the E-field also had a significant influence on the strength of the weak interactions. Furthermore, the calculation of the Laplacian bond order, which characterized the C-NO₂ bonds as trigger bonds, predicted that the E-fields could change the thermal decomposition process of DNTF while the positive E-field facilitates the breakdown of the C-NO₂ in DNTFⅣ molecules. Our work provides new insights into the relationship between the E-field and the intermolecular vibration energy transfer and decomposition mechanism of the DNTF system.