Characterization and Properties of F/GAP/CL-20 Energetic Fibers with High Energy and Low Sensitivity Prepared by the Electrospinning Method.

In this work, three samples of fluoroelastomers/glycidyl azide polymer/hexanitrohexaazaisowurtzitane (F/GAP/CL-20) energetic fibers with F/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 F/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 F/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 F/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 F/GAP/CL-20 are mainly CH, HO, N and CO. The results of the energy performance evaluation showed that the standard specific impulse ( ) of F/GAP/CL-20 was 2668.1 N s kg, which was remarkably higher than of the state-of-the-art AP/HTPB/Al propellant. In addition, compared to that of CL-20, the friction sensitivity of one F/GAP/CL-20 sample decreased by 38%, and the sensitivities of the other two F/GAP/CL-20 samples were even less than zero. F/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.