Fabrication of energetic aluminum core/hydrophobic shell nanofibers via coaxial electrospinning

Abstract The structural optimization of the nano-sized composite energetic materials has received worldwide attention. Here, a novel super encapsulating structured polyvinylidene fluoride@glycidyl azide polymer/nitrocellulose (PVDF@GAP/NC) core-shell nanofibers with superior hydrophobic characteristic and enhanced reaction performance was designed and manufactured by innovative coaxial electrospinning. The morphologies confirmed that the aluminum nanoparticles (Al NPs) were effectively loaded on the core fibers and evidenced the efficient encapsulation of the core-shell nanofibers. Thermal analysis showed that the exothermic property of the obtained composite films was controllable and the maximum heat release was observed at Al-50, with a value of 2517 J/g. In addition, the enhanced reaction performance was assessed with flame propagation velocity and plasma electron characteristics, while Al-10, Al-30, Al-50, and Al-70 demonstrated a flame propagation velocity of 0.11, 0.46, 0.8, 0.47 m/s, respectively. Overall, results showed that coaxial electrospinning, as an evolution of the conventional electrospinning, is an effective method to optimize nano-structures, which could supply more reactive sites and better contact between reactants contributing to the improvement of the reaction performance. Furthermore, the great compatibility of coaxial electrospinning with microelectromechanical systems may be capable of facilitating the practical applications of metastable intermixed composites (MICs).