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Density profiles and surface tensions of polymers near colloidal surfaces

A. A. Louis·P. G. Bolhuis·E. J. Meijer·J. P. Hansen
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Abstract

The surface tension of interacting polymers in a good solvent is calculated theoretically and by computer simulations for a planar wall geometry and for the insertion of a single colloidal hard-sphere. This is achieved for the planar wall and for the larger spheres by an adsorption method, and for smaller spheres by a direct insertion technique. Results for the dilute and semi-dilute regimes are compared to results for ideal polymers, the Asakura-Oosawa penetrable-sphere model, and to integral equations, scaling and renormalization group theories. The largest relative changes with density are found in the dilute regime, so that theories based on non-interacting polymers rapidly break down. A recently developed ``soft colloid'' approach to polymer-colloid mixtures is shown to correctly describe the one-body insertion free-energy and the related surface tension.

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A. A. Louis, P. G. Bolhuis, E. J. Meijer, J. P. Hansen. 2001-11-29. Density profiles and surface tensions of polymers near colloidal surfaces. https://doi.org/10.1063/1.1473658

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