Modification of cyclotrimethylenetrinitramine/fluororubber composites by manganese–copper bimetallic phenolic network

Abstract Fast and easy coating strategies are crucial in improving the safety of energetic materials. Therefore, in this study, the bimetallic phenolic network (BMPN) assembled by protocatechuic acid (PCA), manganese ion (Mn 2+ ) and copper ion (Cu 2+ ) was used to modify cyclotrimethylene trinitramine (RDX) by in situ polymerization, and then the fluororubber (F2603) was coated by the microemulsion method to form RDX@Mn/Cu‐BMPN@F2603 double‐layer core‐shell composite material. The results showed that RDX@Mn/Cu‐BMPN@F2603 composites have a regular morphology and good dispersion. Compared with the raw material RDX, the thermal decomposition peak temperature of modified RDX and other RDX‐based composites was delayed, the thermal stability was significantly improved, and the mechanical sensitivity was reduced. Among them, the Mn/Cu‐BMPN@F2603 composite coating had a better modification effect on RDX, with its activation energy elevated to 227.59 kJ·mol −1 , the impact sensitivity increased by 39 J, and the friction pressure increased by 180 N, which can effectively meet the requirements of advanced energy‐containing materials for safety and stability. Highlights Proved that PCA‐based BMPN can self‐assemble on crystal surfaces. Prepared by microemulsion method polymer‐bonded explosive (PBX). BMPN coating significantly improved the safety performance of PBX. The Mn/Cu‐ BMPN can be modified better than Mn‐ MPN and Cu‐ MPN .