Dispersions of multi-walled carbon nanotubes in liquid crystals: new challenges to molecular theories of anisotropic soft matter

TL;DR

This paper presents a theoretical model for the aggregation behavior of multi-walled carbon nanotubes in nematic liquid crystals, highlighting new challenges to existing molecular theories of anisotropic soft matter.

Contribution

It introduces a novel model describing nanotube aggregation as large quasi-particles with a skeleton and shell structure, aligning well with experimental observations.

Findings

Aggregation size depends on nanotube concentration and aspect ratio

The model explains the fractal nature of aggregates

Experimental data supports the theoretical predictions

Abstract

Aggregation of carbon nanotubes dispersed in nematic liquid crystalline medium is discussed. A model is proposed, which assumes that the aggregates consist of a "skeleton" formed by stochastically arranged nanotubes and a "shell" ("coat") of incorporated and adjacent nematic molecules. The aggregates of this type can be considered as large quasi-macroscopic particles in the nematic matrix. The resulting composite system represents a new type of complex molecular liquids involving self-organization of particles in anisotropic medium. Many essential features and implications of the theoretical model (e.g., effects of concentration of the nanotubes, their aspect ratio and orientational order parameter on the size and fractal dimensionality of the aggregates formed, as well as on the rate of aggregation) are in good agreement with experimental data obtained by various physical methods.