WEB Manipulation of carbon nanoparticles in composites during processing for improved electrical propertiesTuesday (22.09.2020) 17:05 - 17:20 P: Processing and Synthesis 1 Part of:
Manipulation of carbon nanotubes (CNTs) and other carbon nanoparticles in liquid media through the application of electric fields has been frequently addressed in literature. Given the high aspect ratio and electrical conductivity of CNTs, induced polarisation takes place in the presence of an electric field, leading to dielectrophoresis and Coulombic interactions. This is thought to promote their movement in the liquid due to electric synergies and hence to improve the electric conductivity of the composite at a given SWCNT loading.
Experimental setups were developed for investigations of dielectrophoresis in thermoset composite systems with single-walled carbon nanotubes (SWCNTs). The SWNTs were dispersed in an epoxy resin as electrically conductive filler. Epoxy/SWNT nanocomposites were produced by curing while applying both DC and AC electric fields to the system in order to improve the through-plane electrical conductivity of the plate shaped samples.
Parameters such as electric field strength and frequency, curing temperature and filler concentration were investigated. While DC fields appear not to have much impact on the composites electrical resistivity, AC fields enabled a reduction of up to around 10 times in comparison with the samples produced without electric fields at only 0.01 wt.% loading.
This technique presents promising results for enhancing the electrical conductivity of polymer composites with carbon-based nanoparticles by influencing the nano- and micro structure of the filler network during the curing step.