Interference of dynamical arrest, thermodynamic instabilities and energy-scale competition in symmetric binary mixtures

Abstract

While energy scale competition dictates equilibrium phase behavior, kinetic barriers often drive soft-matter mixtures into dynamically arrested states, rendering conventional phase diagrams incomplete. We extend the classification of binary systems into regions of thermodynamic instability to explore the interplay between phase separation and dynamical arrest. Strong cross-attractions kinetically suppress demixing, whereas competitive energy scales yield either condensation- or demixing-driven amorphous states. We show that this morphological crossover is parameterized by a structural order parameter, $χ$, providing a unified non-equilibrium framework that reconciles theoretical predictions with experimentally observed arrested mixtures.