Processing and Characterization of Carbon Nanotube Enhanced Energetic Materials
Future generations of aircraft design will increasingly make use of internal carriages to help enhance the stealth capabilities of the aircraft by reducing radar cross-section and drag. This places an increased focus on designing munitions and energetic materials to fit advancing needs of high energy density and low sensitivity. Polymer bonded explosives (PBX) notably suffer from high levels of sensitivity to accidental detonation induced by the presence of a thermomechanical insult. Current strategies for desensitizing of PBX come at the expense of a significant reduction in performance. A possible method for desensitizing PBX without adverse performance effects is multifunctional tailoring of the mechanical properties through the strategic incorporation of multi-walled carbon nanotubes directly into the binder phase. The addition of the CNTs should provide an increased level of viscoelastic dissipation and load transferring to shield the crystals from the effects of a thermomechanical force, while also increasing the thermal conductivity to provide increased pathways for heat conduction away from induced hot spots prior to detonation. In this work, a fabrication method was put together to produce consistent polymer bonded simulants (PBS), followed by characterization of their microstructure, and experimental testing to determine the effects of CNT concentration. Thermal testing showed the thermal conductivity of the PBS increased with increasing CNT concentration. Low strain rate compression testing showed evidence of a CNT induced structural skeleton effect that provides the binder with an increased interfacial adherence, load transfer, and an ability to absorb higher levels of deformation. These efforts show the potential of CNT enhanced energetic materials.