Dispersions of High-Quality Carbon Nanotubes with Narrow Aggregate Size Distributions by Viscous Liquid for Conducting Polymer Composites

Preserving the quality of carbon nanotubes (CNTs) is essential to fully utilize the characteristics in dispersions and other forms. To fabricate CNT dispersions retaining the quality, we propose to reduce CNT aggregate size distributions by viscous liquids at the initial stage from as-grown CNT powders originally possessing a wide aggregate size distribution. Higher viscosity solvents were found to highly disentangle the CNT powder and give a narrower CNT aggregate size distribution without impairing the quality. To show the advantages of these CNT dispersions, we demonstrated a 104-fold increased electrical conductivity of CNT rubber composite based on the predispersion step of CNT powder in the rubber base compound with high viscosity. Our method can afford a high quality of CNT and avoid a long, heavy dispersion, which was conventionally carried out to decrease entangled, large size CNT aggregates, furthermore, applicable for fabrication of conducting polymer composites.