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Viscosity of Polyelectrolytes: Influence of Counterion and Solvent Type
Anish Gulati1, Carlos G Lopez1,2
1Institute of Physical Chemistry, RWTH Aachen University, Aachen, 52056, Germany.
Abstract:
We study the viscosity of polystyrenesulfonate with sodium and tetrabutylammonium counterions in aqueous and organic solvent media. We find that at low concentrations the Fuoss law (ηsp ∼ c1/2) is approximately obeyed, but at higher concentrations, an exponential dependence on the polymer volume fraction sets in. These findings are discussed in terms of Fujita's free volume theory.
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