Synthesis and characterization of next-generation multifunctional material architectures : aligned carbon nanotube carbon matrix nanocomposites

Abstract

Materials comprising carbon nanotube (CNT) aligned nanowire (NW) polymer nanocomposites (A-PNCs) have emerged as promising architectures for next-generation multifunctional applications. Enhanced operating regimes, such as operating temperatures, motivate the study of CNT aligned NW ceramic matrix nanocomposites (A-CMNCs). Here we report the synthesis of CNT A-CMNCs through the pyrolysis of CNT A-PNC precursors, creating carbon matrix CNT A-CMNCs. The CNT A-CMNC processing parameters were evaluated using an apparent density measurement, polymer re-infusion modeling, and CNT quality analysis, which elucidate the limitations of the processing parameters currently used to fabricate CNT A-CMNCs. Theoretical tools developed to help quantify and analyze the morphology of the CNTs in the A-CMNCs, and NWs in general, show that morphological parameters, such as NW outer diameter and inter-wire spacing, that are usually overlooked may have significant effects on the physical properties of NW architectures. Mechanical characterization of the CNT A-CMNCs illustrates that the presence of aligned CNTs can lead to an enhancement of > 60% in microhardness, meaning that the fabrication of high strength, high temperature, lightweight next-generation material architectures may be possible using the presented method. Finally, factors that influence the physical properties of CNT A-CMNCs, such as CNT waviness and the porosity of the carbon matrix, are identified, and since their effects cannot be modeled using existing theory, future paths of study that could enable their quantification are recommended.