Controlling the Interactions between Soft Colloids via Surface Adsorption

TL;DR

This study uses simulations and theory to explore how surface adsorption influences the shape and interactions of star polymers, revealing significant effects of two-dimensional confinement on their behavior.

Contribution

It provides new insights into the conformations and interactions of star polymers under surface adsorption, highlighting the impact of geometric confinement on soft colloids.

Findings

Star size scales as f^{1/4} with the number of arms

Effective interaction scales as f^{2}

Confinement dramatically alters polymer conformations and interactions

Abstract

By employing monomer-resolved computer simulations and analytical considerations based on polymer scaling theory, we analyze the conformations and interactions of multiarm star polymers strongly adsorbed on a smooth, two-dimensional plane. We find a stronger stretching of the arms as well as a stronger repulsive, effective interaction than in the three dimensional case. In particular, the star size scales with the number of arms $f$ as $\sim f^{1/4}$ and the effective interaction as $\sim f^{2}$, as opposed to $\sim f^{1/5}$ and $\sim f^{3/2}$, respectively, in three dimensions. Our results demonstrate the dramatic effect that geometric confinement can have on the effective interactions and the subsequent correlations of soft colloids in general, for which the conformation can be altered as a result of geometrical constraints imposed on them.