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Rheology of carbon nanotube dispersions

Y. Y. Huang·S. V. Ahir·E. M. Terentjev
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Abstract

We report on rheological properties of a dispersion of multi-walled carbon nanotubes in a viscous polymer matrix. Particular attention is paid to the process of nanotubes mixing and dispersion, which we monitor by the rheological signature of the composite. The response of the composite as a function of the dispersion mixing time and conditions indicates that a critical mixing time t* needs to be exceeded to achieve satisfactory dispersion of aggregates, this time being a function of nanotube concentration and the mixing shear stress. At shorter times of shear mixing, t t*, has several universal rheological features; at nanotube concentration above a characteristic value ~2-3wt% the effective elastic gel network is formed, while the low-concentration composite remains a viscous liquid. We use this rheological approach to determine the effects of aging and re-aggregation.

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Y. Y. Huang, S. V. Ahir, E. M. Terentjev. 2006-02-07. Rheology of carbon nanotube dispersions. https://arxiv.org/abs/cond-mat/0602187

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