Role of a polymeric component in the phase separation of ternary fluid mixtures: A dissipative particle dynamics study

TL;DR

This study uses dissipative particle dynamics simulations to explore how a polymeric component influences phase separation and domain morphology in ternary fluid mixtures, revealing a crossover in growth regimes.

Contribution

It demonstrates the impact of polymer chain length, composition, and stiffness on phase separation dynamics in ternary fluids, highlighting the universality class and parameter-dependent scaling functions.

Findings

System exhibits a crossover from viscous to inertial hydrodynamic regimes.

Domain size scales as t^φ with φ transitioning from 1 to 2/3.

Scaling functions depend on polymer parameters, affecting morphology evolution.

Abstract

We present the results from dissipative particle dynamics (DPD) simulations of phase separation dynamics in ternary (ABC) fluids mixture in $d=3$ where components A and B represent the simple fluids and component C represents a polymeric fluid. Here, we study the role of polymeric fluid (C) on domain morphology by varying composition ratio, polymer chain length, and polymer stiffness. We observe that the system under consideration lies in the same dynamical universality class as a simple ternary fluids mixture. However, the scaling functions depend upon the parameters mentioned above as they change the time scale of the evolution morphologies. In all cases, the characteristic domain size follows: $l(t) \sim t^{\phi} $ with dynamic growth exponent $\phi$, showing a crossover from the viscous hydrodynamic regime $(\phi=1)$ to the inertial hydrodynamic regime $(\phi=2/3)$ in the system at late times.