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Effective interactions between star polymers and colloidal particles

A. Jusufi·J. Dzubiella·C. N. Likos·C. von Ferber·H. Loewen
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Abstract

Using monomer-resolved Molecular Dynamics simulations and theoretical arguments based on the radial dependence of the osmotic pressure in the interior of a star, we systematically investigate the effective interactions between hard, colloidal particles and star polymers in a good solvent. The relevant parameters are the size ratio q between the stars and the colloids, as well as the number of polymeric arms f (functionality) attached to the common center of the star. By covering a wide range of q's ranging from zero (star against a flat wall) up to about 0.75, we establish analytical forms for the star-colloid interaction which are in excellent agreement with simulation results. A modified expression for the star-star interaction for low functionalities, f < 10 is also introduced.

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A. Jusufi, J. Dzubiella, C. N. Likos, C. von Ferber, H. Loewen. 2000-12-20. Effective interactions between star polymers and colloidal particles. https://doi.org/10.1088/0953-8984%2F13%2F28%2F303

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