Electrospinning Preparation of NC/GAP/Submicron-HNS Energetic Composite Fiber and its Properties

In this work, novel three-dimensional nitrocellulose/glycidyl azide polymer/submicron-2,2', 4,4', 6,6'-hexanitro-stilbene (NC/GAP/submicron-HNS) composite fibers were prepared by the electrospinning method. As-prepared NC/GAP/submicron-HNS fibers were continuous and possessed a large specific surface area. The structure of fibers was characterized by energy-dispersive X-ray, X-ray photoelectron spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy (IR). The results showed that HNS submicron particles were uniformly loaded on the surface of NC/GAP fibers and incorporated with it. Thermal analyses were performed. Such NC/GAP/submicron-HNS fibers showed a low activation energy of 204 kJ·mol^-1 and large rate constant of 1.74 s^-1, indicating high reactivity and fast reaction rate. The result of TG-IR analysis revealed that the main decomposition products of NC/GAP/submicron-HNS were CO₂, CO, H₂O, N₂O, few NO, and fragments such as -CH₂O- and -CH-, which were low-signature gases. An evaluation on the energy performance disclosed that the standard specific impulse (I _sp) of NC/GAP/submicron-HNS fibers was 2032 N·s·kg^-1, which was higher than 2014 N·s·kg^-1 of NC/GAP. This meant the addition of HNS submicron particles to the NC/GAP fiber was favorable to the improvement of energy performance. Additionally, introduction of submicron-HNS made the energetic fibers becoming very insensitive to impact action. It was expected that as-prepared NC/GAP/submicron-HNS membranes were promising materials applied for solid rocket propellant.