Enhanced Electrical Conductivity of Nanocomposites Containing Hybrid Fillers of Carbon Nanotubes and Carbon Black

TLDR

The novelty of this work lies in the synergy arising from combining two conducting fillers with distinct geometries, aspect ratios, and dispersion characteristics that have not been previously considered. The study develops epoxy nanocomposites reinforced with hybrid CNT and CB fillers to enhance electrical conductivity while maintaining balanced mechanical properties and reducing cost. Epoxy-based nanocomposites were fabricated with varying CNT/CB combinations and their electrical and mechanical properties were evaluated. The hybrid fillers lowered the percolation threshold to 0.2 wt % for both CNTs and CB and simultaneously improved ductility and fracture toughness, confirming a synergistic effect.

Abstract

Nanocomposites reinforced with hybrid fillers of carbon nanotubes (CNTs) and carbon black (CB) are developed, aiming at enhancing the electrical conductivity of composites with balanced mechanical properties while lowering the cost of the final product. Epoxy-based nanocomposites were prepared with varying combinations of CNTs and CB as conducting fillers, and their electrical and mechanical properties were evaluated. It was shown that the addition of CNTs in CB composites enhanced the electrical conductivity of composites: a low percolation threshold was achieved with 0.2 wt % CNTs and 0.2 wt % CB particles. The CB particles also enhanced the ductility and fracture toughness of nanocomposites, confirming the synergistic effect of CB as a multifunctional filler. The novelty of this work lies in the synergy arising from the combination of two conducting fillers with unique geometric shapes and aspect ratios as well as different dispersion characteristics, which have not been specifically considered previously.