Rapid Polymerization of Dopamine for Coating on TKX-50 Surface with Exceptional Thermal Stability and Mechanical Properties

Polymer-bonded explosives (PBX), as a classical representative of energetic composite materials, have poor mechanical properties due to weak interface interaction, which limits their wide application. Inspired by the strong adhesion of mussels, coating polydopamine (PDA) on the surface of energetic materials is considered an effective method to enhance the interaction. In this study, the self-polymerization of dopamine was accelerated by the addition of potassium permanganate, which was successfully coated on the surface of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50), a high-energy and insensitive energetic material. After PDA coating, TKX-50 had excellent thermal stability and mechanical properties. The spontaneous decomposition temperature and thermal explosion critical temperature of TKX-50 after PDA coating increased from 204.300 and 217.604 °C to 210.700 and 223.839 °C, respectively, and the compressive strength increased from 6.38 to 7.65 MPa. This novel method improves the thermal stability and mechanical properties of energetic materials to ensure their large-scale industrial production and application.