Preparation, structure, and reaction characteristics of TKX-50-AP composites

Based on the feasibility of the combination of dihydroxylammonium-5,5'-bistetrazolyl-1,1'-diolate (TKX-50) and ammonium perchlorate (AP) determined by molecular dynamics simulations, TKX-50-AP composites were prepared using the solvent-non-solvent method. The ignition and combustion pressure characteristics of four materials, namely, TKX-50, AP, TKX-50-AP mixture, and TKX-50-AP composite, were comparatively studied using a self-designed annular ignition combustion device and a 100 mL closed burst apparatus. Combined with the results of thermal analysis and mass spectrometry, the reaction characteristics of the TKX-50-AP composites were discussed. The results showed that AP could be uniformly coated on the surface of TKX-50 crystals through recrystallization, forming spherical or ellipsoidal TKX-50-AP composites with a relatively stable core-shell structure. Compared to the TKX-50-AP mixture, the mechanical sensitivity of the composite significantly reduced. The main growth crystal planes of TKX-50 and AP primarily interacted through hydrogen bonds. After the composite of TKX-50 and AP was formed, its combustion performance was evaluated and determined to be better than those of both the raw materials (TKX-50 and AP) and the TKX-50-AP mixture. Further, it exhibited the same high burn rate as TKX-50 while improving gas release during combustion. Compared to the TKX-50-AP mixture, under plasma initiation, AP in the TKX-50-AP composite could react more fully with the C, H, O, and N elements in TKX-50, thereby improving the reaction characteristics of TKX-50.