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arXiv · 1405.0978

Depletion effects in colloid-polymer solutions

Giuseppe D'Adamo·Andrea Pelissetto·Carlo Pierleoni
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Abstract

The surface tension, the adsorption, and the depletion thickness of polymers close to a single nonadsorbing colloidal sphere are computed by means of Monte Carlo simulations. We consider polymers under good-solvent conditions and in the thermal crossover region between good-solvent and $θ$ behavior. In the dilute regime we consider a wide range of values of $q$, from $q = 0$ (planar surface) up to $q\approx 30$-50, while in the semidilute regime, for $ρ_p/ρ_p^*\le 4$ ($ρ_p$ is the polymer concentration and $ρ_p^*$ is its value at overlap), we only consider $q = 0,0.5,1$ and 2. The results are compared with the available theoretical predictions, verifying the existing scaling arguments. Field-theoretical results, both in the dilute and in the semidilute regime, are in good agreement with the numerical estimates for polymers under good-solvent conditions.

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Giuseppe D'Adamo, Andrea Pelissetto, Carlo Pierleoni. 2014-05-05. Depletion effects in colloid-polymer solutions. https://doi.org/10.1080/00268976.2013.836255

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