Design of Polydopamine@iron Oxide-Coated Ammonium Perchlorate Core-Shell Composites for Enhancing the Combustion...

An ammonium perchlorate (AP) composite system with double-coating encapsulation based on the interfacial polymerization behavior of dopamine (DA) in Pickering emulsions was designed to enhance the combustion performance of HTPB-based propellants. The composite system proved highly effective in mitigating the agglomeration issues associated with iron oxide nanoparticles (Fe₂O₃ NPs) as catalysts, with the AP exhibiting superior performance compared to the composite comprising pure Fe₂O₃ NPs. The results of the thermal decomposition experiments showed that the HTD temperature of AP@PDA@Fe₂O₃ was reduced to 318.8 °C, accompanied by a 183.8% increase in heat release and an approximately 30.0% decrease in the activation energy. The combustion rate of AP@PDA@Fe₂O₃/HTPB was enhanced by approximately 3.0 times higher than that of AP/HTPB. Furthermore, experimental results on safety and surface hydrophobicity showed that the impact sensitivity of the composite AP increased by 28.6%, while the water contact angle was markedly elevated. The reason for the performance enhancement was the synergistic catalytic effect of PDA/Fe₂O₃ on AP and the dense double-coated structure. This study provided a new idea for the multilevel surface modification of other energy-containing materials.