Mechanical response of carbon nanotube reinforced particulate composites with implications for polymer bonded explosives

Abstract

Modern polymer bonded explosives (PBX) are often characterized by a sensitive response to external thermomechanical insult that in some cases lead to accidental detonation. Current strategies for desensitizing PBXs come at the expense of a significant reduction in performance. A possible method for desensitizing PBX without adverse performance effects is the multifunctional tailoring of mechanical properties through strategic incorporation of multi-walled carbon nanotubes (MWCNTs) directly into the binder phase. In this work, a fabrication method is presented that produces polymer bonded simulants (PBS) of PBX that incorporate MWCNTs into the binder phase, hydroxyl-terminated polybutadiene (HTPB). These materials were characterized via microscopy and unconfined quasi-static compression testing to determine the effects of MWCNTs. Quasi-static compression showed evidence of a MWCNT induced structural skeleton effect that provided the binder with an increased strength, load transfer, and a greater ability to resist strain localizations prior to failure. These enhancements demonstrate the potential of using MWCNTs to enhance energetic materials.