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Structural transitions in aqueous suspensions of natural graphite

Vasily Moraru·Nikolai Lebovka·Dmitrii Shevchenko
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Abstract

The electric conductivity $σ$ and plastic viscosity $η$ of aqueous suspensions at different volume fraction of graphite $ϕ$ and concentration of nonionic surfactant (Triton X-305) are investigated. The correlations between conductivity and rheological properties are discussed. A model of structural transitions in aqueous graphite suspensions is discussed. Two structural transitions, corresponding to changes in electrical and rheomechanical properties, are identified as percolation and sol-gel transitions, respectively. An unusual initial decrease of the bulk electrical conductivity with graphite volume fraction $ϕ$ increase was observed in surfactant solution. This fact is explained as a result of isolating coating formation around the graphite particles.

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Vasily Moraru, Nikolai Lebovka, Dmitrii Shevchenko. 2003-06-14. Structural transitions in aqueous suspensions of natural graphite. https://arxiv.org/abs/cond-mat/0306384

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