Binder-free, pre-consolidated single-walled carbon nanotubes for manufacturing thermoset nanocomposites

Abstract

In this work, we propose a pre-consolidated form of single-walled carbon nanotubes (SWCNT) – SWCNT briquettes – as a binder-free, robust, and safe material for manufacturing electrically and thermally conductive thermoset nanocomposites with universal applicability to all polymer matrices. We prove that the briquettes provide similar performance in nanocomposites compared to reference samples: a pristine powder, a commercial masterbatch and an aerogel based on the same type of SWCNTs. Using comprehensive sets of methods, we observe no significant differences in electrical (∼10−7-1 S/cm depending on SWCNT loading) and thermal (0.210–0.304 W/mK) conductivities for all sample types across a wide range of SWCNT concentrations. Moreover, the percolation thresholds of nanocomposites for SWCNT briquettes were ultra-low and close to that of pre-dispersed masterbatches (0.001–0.003 wt%). Pre-consolidated SWCNT powder is shown to provide the same final functional properties, while being free from common nanotube drawbacks such as the higher price of masterbatch manufacturing or aerosolization and low dispersibility during handling for the SWCNT powder/aerogel. The briquettes not only offer a safe solution for large scale fabrication, cutting away the need for personal and facility level safety measures, but do so at no significant cost increase, can be used with any polymer matrix and associated industrial processing route without any loss of final properties. This makes them universally attractive for all composite industrial production as well as small scale low capital laboratories.