Cure temperature influences electrical properties via carbon nanotube-rich domain formation

Published: July 27, 2016

Author(s)

Chelsea S. Davis, Nathan D. Orloff, Jeremiah W. Woodcock, Christian J. Long, Kevin A. Twedt, Bharath NMN Natarajan, Jonathan E. Seppala, Jabez J. McClelland, Jan Obrzut, James A. Liddle, Jeffrey W. Gilman

Abstract

Carbon nanotube (CNT) nanocomposites are enticing materials that enable engineers to tailor structural and electrical properties for applications in the automotive and aerospace industries. CNT mass fraction and the matrix cure temperature are two ways to tune the direct current and alternating current electrical properties of these nanocomposites; yet, how mass fraction and cure temperature affect electrical properties remains unclear. In many cases, nanofillers such as carbon nanotubes appear in concentrated domains within the nanocomposite. Recent insights into nanoparticle-rich domain formation and its influence on electrical properties raise questions about which processing variables might optimally tune the electrical properties. Utilizing advanced, nondestructive metrology techniques such as scanning lithium-ion microscopy and microwave cavity perturbation, new insights are presented into the role of mass fraction and cure temperature in multiwall carbon nanotube – bisphenol A diglycidyl ether epoxy composites. Here, it is found that both mass fraction and cure temperature affect dispersion quality, leading to a direct effect on the electrical properties. Specifically, it is shown that the DC conductivity is nearly an order of magnitude higher for composites prepared at elevated matrix cure temperatures for a given CNT mass fraction. These findings elucidate pathways to generate designer nanocomposites for advanced electrically active applications.
Citation: Composites Science and Technology
Volume: 133
Pub Type: Journals

Keywords

aggregation, carbon nanotubes, dispersion, ion microscopy, metrology, microwave, nanocomposites, noncontact, nondestructive, resonator
Created July 27, 2016, Updated November 10, 2018