The Phase Diagram of Star Polymer Solutions

TL;DR

This paper uses Monte Carlo simulations to map the phase diagram of star polymer solutions, revealing various stable phases and reentrant transitions depending on density and arm number.

Contribution

It provides the first comprehensive phase diagram for star polymer solutions considering a wide range of densities and arm numbers using ultrasoft pair potentials.

Findings

Identified stable fluid and crystal phases including BCC, FCC, BCO, and diamond.

Discovered reentrant melting and freezing transitions at certain arm numbers.

Mapped phase boundaries across different densities and arm numbers.

Abstract

The phase diagram of star polymer solutions in a good solvent is obtained over a wide range of densities and arm numbers by Monte Carlo simulations. The effective interaction between the stars is modeled by an ultrasoft pair potential which is logarithmic in the core-core distance. Among the stable phases are a fluid as well as body-centered cubic, face-centered cubic, body-centered orthogonal, and diamond crystals. In a limited range of arm numbers, reentrant melting and reentrant freezing transitions occur for increasing density.