Comparing different coarse-grained potentials for star polymers

TL;DR

This paper evaluates various coarse-grained models for star polymers, revealing limitations of phenomenological approaches and identifying the critical functionality range for fluid-solid transition using multiple methods.

Contribution

It introduces a comparative analysis of coarse-grained models for star polymers and determines the minimum functionality for phase transition using Hansen-Verlet and hypernetted chain methods.

Findings

Phenomenological models poorly reproduce thermodynamics.

Minimum functionality for fluid-solid transition: 35 < fc < 40.

Results align with previous studies.

Abstract

We compare different coarse-grained models for star polymers. We find that phenomenological models inspired by the Daoud-Cotton model reproduce quite poorly the thermodynamics of these systems, even if the potential is assumed to be density dependent, as done in the analysis of experimental results. We also determine the minumum value fc of the functionality of the star polymer for which a fluid-solid transition occurs. By applying the Hansen-Verlet criterion we find 35 < fc < 40. This result is confirmed by an analysis based on the modified (reference) hypernetted chain method and is qualitatively consistent with previous work.