The effect of multi-wall carbon nanotube morphology on electrical and mechanical properties of polyurethane nanocomposites

Abstract

In this study, we examine the effect of multi-wall carbon nanotubes (MWCNT) morphology on electrical and mechanical properties of MWCNT-filled polyurethane (PU) nanocomposites. The main objective of this study is to understand the role of aspect ratio and length of MWCNTs in determining the performance of nanocomposites. Highly aligned MWCNTs were prepared by aerosol-assisted chemical vapour deposition method and compared to commercially available MWCNTs in PU matrix for ease of dispersibility and performance. We observed opposing influence of the MWCNT on electrical and mechanical behaviour of the nanocomposites. The electrical properties were proportional to length of the MWCNTs whereas the mechanical properties were dependent on the aspect ratio of the MWCNTs. Moreover, thicker nanotubes (approximately 40nm) with a higher aspect ratio (approximately 225) are less prone to shortening and impart better tensile and storage modulus along with improved electrical and therefore are more suitable for the MWCNT nanocomposites.