Analysis and measurement of carbon nanotube dispersions: nanodispersion versus macrodispersion

Abstract

Because of their unique mechanical, optical, thermal and electrical properties, carbon nanotubes (CNTs) form the basis for a wide variety of multifunctional devices and materials; many of these applications require that CNTs be dispersed and processed in liquids such as organic solvents, polymer melts or surfactant solutions. One of the most problematic issues affecting the CNT research community is the lack of standards and uniform characterization methods for CNT dispersion. A 2005 NASA‐NIST workshop aimed to address this issue and made a clear distinction between ‘nanodispersion’ of individual CNTs and ‘macrodispersion’ of CNT bundles. Unfortunately, this distinction has yet to percolate through the CNT dispersion literature. The present article seeks to elucidate and commend these concepts, identify the situations where this difference is most critical, note some scenarios where these concepts have been underutilized and posit experimental and computational characterization methods for quantifying the degree of nanodispersion. Particular attention is devoted to the controversial claims of complete nanodispersion and how such claims may be verified. Copyright © 2010 Society of Chemical Industry

Structure and properties of multi-walled carbon nanotube porous sheets with enhanced elongation

“…The structure of the CNT dispersions was investigated immediately after their preparation by cryo-TEM, which preserves the structure present in the dispersion [38]. Cryo-TEM is a well-known method for the characterization of CNT dispersions [39][40][41][42][43]. MWNTs are marked with white arrow in the cryo-TEM image on Fig.…”

Carbon Nanotubes in the Liquid Phase: Addressing the Issue of Dispersion

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High‐Performance Pristine Graphene/Epoxy Composites With Enhanced Mechanical and Electrical Properties

“…The graphene dispersion quality (i.e., concentration, average number of layers, and level of covalent functionalization) strongly influences the properties of the reinforced polymer composites; excellent dispersion quality ensures a high specific surface area which would guarantee the strong filler/matrix adhesion in the composite. The percolation threshold is largely determined by the effective filler aspect ratio, which is also controlled by nanofiller dispersion quality and resistance to aggregation 5…”