Efficiently Constructed Core-Shelled Structured AP-Based Composites with Excellent Balance of High Energy Release and Low Sensitivity.

Ammonium perchlorate (AP) plays an important role in solid propellants because of its high specific impulse, high energy density and low cost. However, the excellent performance cannot conceal the many shortcomings of AP, and the problems of non-concentrated exothermic, high sensitivity and hygroscopicity still seriously impede its application in solid propellants. In this study, the solvent evaporation method is used to directionally modify the order of the cupric oxide (CuO) and fluororubber (F) shell layers so as to obtain AP-based composites with different core-shell structures. The interlayer binding energies of the composites with different structures are explored by theoretical calculations, and it is demonstrated that AP-based composites have excellent stability. In addition, CuO with valence-band holes not only reduces the peak temperature of the high temperature decomposition of AP (440.4 to 354.5 °C), but also enhances its combustion properties by undergoing thermite reaction with Al. Furthermore, the excellent hydrophobicity and barrier properties of F greatly strengthened the hydrophobicity and mechanical properties of the AP-based composites and reduced their sensitivity. In summary, the core-shelled structures AP-based composites prepared by this strategy possessed 5-in-1 excellent properties, which provided a new idea for targeted modulation of the properties of energetic materials.