Unusual Coarsening During Phase Separation in Polymer Systems

TL;DR

This paper presents a kinetic model for phase separation in polymer systems, revealing an unusual coarsening law during intermediate stages and crossover behaviors influenced by network connectivity.

Contribution

It introduces a new kinetic model that explicitly incorporates polymer chain connectivity, explaining atypical coarsening laws during phase separation.

Findings

Unusual coarsening law $R \,\sim\, t^{1/(d+3)}$ during intermediate stages

Crossover to logarithmic coarsening law as network breaks down

Recovery of classical Lifshitz-Slyozov law at late stages

Abstract

We introduce a kinetic model of coarsening of transient polymer networks during the intermediate stages of phase separation in polymer systems. The model explicitly takes into account the effect of the connectivity of polymer chains. We show that during the intermediate stages the size of the droplet grows according to an unusual coarsening law $R \sim t^{1/(d + 3)}$. When the network structure breaks up, the coarsening law may cross over to $R \sim \ln t^{-1}$, until only at very late stages the Lifshitz-Slyozov coarsening law $R \sim t^{1/3}$ is recovered.