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In this work, three samples of fluoroelastomers/glycidyl azide polymer/hexanitrohexaazaisowurtzitane (F2602/GAP/CL-20) energetic fibers with F2602/GAP:CL-20 ratios of 1:9, 2:8, and 3:7 were prepared by the electrospinning method. The morphologies and structures of the samples were characterized by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The results revealed that F2602/GAP/CL-20 energetic fibers showed a three-dimensional network structure, and four elements C, N, O, and F were observed on the surface. The surface of the fiber F2602/GAP:CL-20 = 1:9 was uniform and smooth. Differential scanning calorimetry was used to analyze the thermal decomposition properties of the samples. The apparent activation energy of the F2602/GAP/CL-20 energetic fiber was 399.86 kJ/mol, indicating high thermal stability. TG-MS analysis results show that the thermal decomposition products of F2602/GAP/CL-20 are mainly C2H6, H2O, N2, and CO2. The results of the energy performance evaluation showed that the standard specific impulse (I sp) of F2602/GAP/CL-20 was 2668.1 N s kg–1, which was remarkably higher than I sp of the state-of-the-art AP/HTPB/Al propellant. In addition, compared to that of CL-20, the friction sensitivity of one F2602/GAP/CL-20 sample decreased by 38%, and the sensitivities of the other two F2602/GAP/CL-20 samples were even less than zero. F2602/GAP/CL-20 fibers also exhibited a higher feature height. Therefore, these kinds of CL-20-based fibers are high-energy materials with very low sensitivity.

In this article, a eutectic mixture was prepared by mixing 1‐methyl‐3,4,5‐trinitropyrazole (MTNP) and pentaerythritol tetranitrate (PETN) by a new method. The T−X phase diagram and H−X phase diagram were obtained by means of DSC analysis, and then the ratio of the eutectic was obtained. All systems displayed simple eutectic behavior. Energy‐dispersive X‐ray spectroscopy (EDS), X‐ray diffraction (XRD), Fourier transform infrared (IR) spectroscopy, and X‐ray photoelectron spectroscopy (XPS) were performed to characterize the structure of the eutectic. Thermodynamic analysis and TG‐MS tests were carried out to explore the thermal decomposition of the eutectic. Then, the mechanical sensitivity and thermal sensitivity of the raw materials and the eutectic were tested, and the detonation performance was also calculated. The results show that the compatibility of the components of the eutectic is not perfect because of the intermolecular forces between the raw materials. Thermal the decomposition products are mainly H2, H2O, N2, CO, NO, N2O and CO2 and a small amount of CH4. The eutectic has the characteristics of high energy and insensitivity and is expected to replace TNT‐based molten cast explosives.

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