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arXiv · 1812.03329

Very long-range attractive and repulsive forces in Model Colloidal Dispersions

Alfredo González-Calderón·Enrique González-Tovar·Marcelo Lozada-Cassou
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Abstract

Experiments with polymer latex solutions show the coexistence of order-disorder structures of macroions. Because of the large macroions' sizes, this order-disorder phase coexistence imply the existence of very long-range attractive and repulsive forces, which can not be explained in terms of conventional direct interaction potentials, which are short-range. Here we apply an integral equations theory to a simple model for colloidal dispersions, at finite concentrations, calculate the particles distribution functions and the involved effective forces. We find very long-range attractive and repulsive forces among the like-charged macroions. The distribution functions are in qualitative agreement with experimental results. The origin of these forces are discussed in terms of an energy-entropy balance.

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Alfredo González-Calderón, Enrique González-Tovar, Marcelo Lozada-Cassou. 2018-12-08. Very long-range attractive and repulsive forces in Model Colloidal Dispersions. https://doi.org/10.1140/epjst%2Fe2018-800089-0

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