| Aluminum/fluorine polymer energetic material is a kind of new advanced energetic material. Its high energy, insensitive and unique energy release characteristics, making it a kind of very important upgrades civilian defense industry new energetic materials. Study abroad about aluminum/fluorine polymer energetic material is more energy release characteristics of micron energetic materials, some foreign reports about nanoscale materials research focus mainly on the preparation of nano-aluminum, surface modification and effective combination of metal and fluoropolymers. As a nano-size effect and interface effect systematic study of the impact of energetic systems has not been reported. Based on the research at home and abroad, we explore the preparation of the new nano-aluminum/fluoropolymer core-shell structure of energetic powders, and explore its release characteristics.In the preparation process of the material, we creatively put forward the view that the composite fluororubber material acts as both the binder and a reactant. Using its characteristic of being soluble in organic solvent to achieve coating aluminum particles, so that the energetic system will not introduce impurities. We also conducted a surface functionalization before the fluoropolymer coating process of the aluminum particles. Functionalized shell can make the particles isolated from the air, keeping the activity of nanometer Al. This will not only solve the problem of the stability of the material in the air due to the large surface area, but also the functionalized shell can play the role of organic transition in the fluoropolymer coating process after, which can make fluoropolymer and aluminum particles bonded more closely, and improving the material structural characteristics from the above two aspects.In this paper, the energy release characteristics of new nano-aluminum/fluoropolymers energetic structure materials were explored. Including static energy release characteristics and impact energy release characteristics. We set up parallel experiments of new nano aluminum energetic materials and traditional micron aluminum energetic materials. Using the testing technology such as XRD, TEM, SEM and TG-DSC, for the characterization of structure and physicochemical properties of the sample.Static energy release performance as an important parameter responds well to the energy density levels and reactivity of energetic materials. The combustion heat and explosion heat measured of the aluminum content of 50% aluminum/fluoropolymer material is 18 k J/g and 7kJ/g. And in the ignition experiments, the nano-aluminum content more than 26.5% of the materials have all successful ignition in the air, when the micron aluminum content only reach 50% can the material be successfully ignited. This result shows that the nano-aluminum energetic materials have higher activity and lower reaction threshold than the conventional micron aluminum energetic materials.In experiments to explore the impact energy release feature section, we explored the bulk materials flyer impact energy release characteristics and plane films materials laser shock energy release characteristics. Successfully found a localized "hotspots" phenomenon, and the impact reactive threshold has been explored. Impact reactive threshold of micron aluminum/ fluoropolymer energetic materials is aluminum content of 10%, flyer impact velocity at 3.07km/s; while the nano aluminum/fluoropolymer impact reactive threshold condition is aluminum content 10%, flyer impact velocity at 2.52km/s. Results show that the aluminum component acts a crucial role on the initiation threshold of the reaction. The applications of nano aluminum in fluoropolymer-based energetic materials, improves the structure of the material, which can absorbs heat and reaches the activation temperature more quickly, thus improving the overall energy density and the energy release rate of the material. |
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