Modulation of composite energetic microunit structure and performance: Synergistic effects of microdroplets and binders

Abstract

Modulating the structure of composite energetic microunits (CEMs) is an effective strategy for improving component homogeneity and safety. In this study, controlled construction of four different HMX/TATB composite microstructures, namely, erythrocyte-like, apple-like, spherical, and cobble-like, using a relatively open coaxial microdroplet template. Based on the theory of synergistic self-assembly between microdroplets and binders, CEMs with tunable structures and particle sizes were successfully prepared. The self-assembly mechanism underlying the formation of CEMs with controllable microstructures was elucidated. The effects of different binder systems on the morphology, structure, and properties of the CEMs were systematically investigated. The results indicate that optimizing the binder system effectively regulates the morphology and structure of the microunits, resulting in high sphericity, narrow particle size distribution, excellent flowability, and high packing density. In addition, binder modulation resulted in varying degrees of improvement in thermal stability and combustion performance. Compared with irregular samples, the self-assembled composite microspheres exhibited more regular morphology, enhanced thermal stability, improved safety, and superior combustion performance. These findings highlight the critical role of binder modulation in controlling microstructure and tuning material properties. Unlike previous reports, this study expands the application of microdroplet technology in composite energetic materials. It proposes a new approach for the synergistic and controllable construction of different microstructure composite particles using microdroplets and binders, providing valuable insights for the structural design and performance optimization of other energetic materials.