Enhanced dispersion and material properties of multi-walled carbon nanotube composites through turbulent Taylor-Couette flow

Abstract

We report enhanced dispersion conditions and electrical properties of multi-walled carbon nanotube (MWCNT) composites through the use of turbulent Taylor-Couette flow. The vortex flow, which is created in a cavity between concentric inner rotating and outer stationary cylinders, provided a uniform dispersion of MWCNTs in a polymer matrix through debundling highly entangled carbon nanotubes. Compared with a three-roll milling process that can apply mechanical shear forces to bundles of MWCNTs, the turbulent Taylor-Couette process generates fluidic shear forces that can more effectively exfoliate MWCNTs, particularly for high MWCNT concentrations. This was validated by the high electrical conductivity that reached 1640 S/m for uniformly dispersed carbon nanotubes in a silicone polymer matrix (at 21.8 Vol% of MWCNT). In view of their high electrical conductivity and uniform dispersion, the MWCNT composites can be promising for rapid electric heating elements. (C) 2017 Elsevier Ltd. All rights reserved.