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Complexation between oppositely charged polyelectrolytes: beyond the Random Phase Approximation

Martin Castelnovo·Jean-Francois Joanny
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Abstract

We consider the phase behavior of polymeric systems by calculating the structure factors beyond the Random Phase Approximation. The effect of this correction to the mean-field RPA structure factor is shown to be important in the case of coulombic systems. Two examples are given: simple electrolytes and mixtures of incompatible oppositely charged polyelectrolytes. In this last case, all former studies predicted an enhancement of compatibility for increasing charge densities; we also describe the complexation transition between the polyelectrolytes. We determine a phase diagram of the polyelectrolyte mixture that includes both complexation and incompatibility.

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Martin Castelnovo, Jean-Francois Joanny. 2001-04-05. Complexation between oppositely charged polyelectrolytes: beyond the Random Phase Approximation. https://arxiv.org/abs/cond-mat/0101279

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