Construction Of HNS With Micro/Nano Hierarchical Structure And Its Performance Based On Supramolecular Assembly-disassembly Method

The grain ultrafined and micro-nano structure of 2,2’,4,4’,6,6’-Hexanitrostilbene(HNS), a typically insensitive high explosive widely used as a secondary explosive in thermally stable charges or perforators, have recently attracted great attention.Compared to the ultrafined scale, the novel micro/nano structure formation and its unique properties of energetic materials(EMs) didn’t get an enough value due to the limitations of innovative thinking and design methods. Therefore, the study on relationship between microstructure and combustion and detonation performance of EMs is relatively lagging. A facile chemical-template method was reported for the preparation of a series of porous micro-nano HNS with hierarchical structure via supramolecular assembly and disassembly. The structure and morphology of each HNS were characterized by X-ray diffraction(XRD), scan electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR), particle size analysis(PSA), and N2adsorption/desorption. Furthermore, the possible formation mechanism of this unique structure is proposed based on the experimental results. And its thermal and sensitivity performance were determined, and the relationships of microstructures and performance were investigated and analyzed. The works of this paper are listed below:(a) HNS was selected as a target explosive, with dioxane as the guidance guest molecule, a special supramolecular structure of HNS and dioxane solvate was chosen to guide the self-assembly in this study. And study the effects of different methods of assembly, such as recrystallization, rapid cooling recrystallization, solvent vapors,infiltration on supramolecular crystal morphology. Furthermore, we will explore more HNS supramolecular system, which provide the initial template for multistage structure.(b) Three-dimensional(3D) porous micro/nano HNS with hierarchical structure has been prepared by a facile chemical-template method named supramolecular assembly and disassembly. Possible formation mechanisms of this HNS with hierarchical structure can be proposed. And study the effects of different methods of dis-assembly, such as in-situ XRD, vacuum pyrolysis, non-solvent extraction, freeze drying, in-situ FTIR on microstructure, obtaining the knowledge of dis-assemblyprocess.(c) The thermal and safety performance and structure tolerance of pressure were studied, obtaining the relationship of microstructures and properties of EMs, which broaden insight and recognition of realizing certain response to stimulus and improving macro performance by the design and control of the structure of EMs.(d) To improve the performance of explosive and further promote the new type of initiating explosive devices, more special microstructures were explored.