Role of the particle size polydispersity in the electrical conductivity of carbon nanotube-epoxy composites

Abstract

Carbon nanotubes (CTNs) with large aspect-ratios are extensively used to establish electrical connectedness in polymer melts at very low CNT loadings. However, the CNT size polydispersity and the quality of the dispersion are still not fully understood factors that can substantially alter the desired characteristics of CNT nanocomposites. Here we demonstrate that the electrical conductivity of polydisperse CNT-epoxy composites with purposely-tailored distributions of the nanotube length L is a quasiuniversal function of the first moment of L. This finding challenges the current understanding that the conductivity depends upon higher moments of the CNT length. We explain the observed quasiuniversality by a combined effect between the particle size polydispersity and clustering. This mechanism can be exploited to achieve controlled tuning of the electrical transport in general CNT nanocomposites.

Surface Modification Design for Improving the Strength and Water Vapor Permeability of Waterborne Polymer/SiO2 Composites: Molecular Simulation and Experimental Analyses

“…A strong supporting tool for studying the interfacial interactions between the polymer matrix and nanoparticles is molecular dynamics (MD) simulations, which has been diffusely used to view the interaction machine-processed between different materials [30][31][32][33][34][35][36][37]. Rissanou et al analyzed several graphene/polymer nanocomposites by atomistic molecular dynamics simulations [38].…”

Antistatic Fibers for High-Visibility Workwear: Challenges of Melt-Spinning Industrial Fibers

“…Fillers’ properties such as their particle size and aspect ratio are known to influence the electrical conductivity of polymer (nano)composites [ 14 , 15 , 16 ]. In particular, the dispersion quality, aspect ratios of carbon nanoparticles, and formation of nanoparticle networks with continuous pathways for efficient electron transport are largely interconnected.…”

“…It is also well known that the polymer–polymer, polymer–filler and filler–filler interactions play an important role in the equilibrium microstructure of the (nano)composite and hence control the achieved electrical conductivity [ 13 ]. Theoretical and experimental investigations suggest that mixing carbon nanoparticles with different shapes and aspect ratios can lead to developing more continuous networks and thus increase the electrical conductivity at a fixed carbon content [ 10 , 13 , 14 , 15 , 16 ]. Molecular simulations have shown that by increasing the aspect ratio, the equilibrium microstructure of nanoparticles in a polymer matrix changes from a random dispersion to a self-assembled morphology and eventually to a bridging self-assembled network [ 14 ].…”

Review on Recent Advancements in the Field of Reinforced Epoxy Nano Composits

“…Gresil et al, [12] studied the thermal diffusivity mapping of graphene Based polymer nanocomposites. Majidian et al, [13] evaluated the role of the particle size, polydispersity in the electrical conductivity of carbon nanotube-Epoxy composites.…”