Correlation between rearrangements and soft modes in polymer glasses during deformation and recovery

Abstract

We explore the link between soft vibrational modes and local relaxation events in polymer glasses during physical aging, active deformation at constant strain rate, and subsequent recovery. A softness field is constructed out of the superposition of the amplitudes of the lowest energy normal modes, and found to predict up to 70% of the rearrangements. Overlap between softness and rearrangements increases logarithmically during aging and recovery phases as energy barriers rise due to physical aging, while yielding rapidly rejuvenates the overlap to that of a freshly prepared glass. In the strain hardening regime, correlations rise for uniaxial tensile deformation but not for simple shear. These trends can be explained by considering the differing degrees of localization of the soft modes in the two deformation protocols.

References in corpus (7)

• Irreversible reorganization in a supercooled liquid originates from localised soft modes
• Identifying structural flow defects in disordered solids using machine learning methods
• The building blocks of dynamical heterogeneities in dense granular media
• Predicting plasticity with soft vibrational modes: from dislocations to glasses
• Distribution of local relaxation events in an aging 3D glass: spatio-temporal correlation and dynamical heterogeneity
• Soft modes and non-affine rearrangements in the inherent structures of supercooled liquids
• A small subset of normal modes mimics the properties of dynamical heterogeneity in a model supercooled liquid

Cited by in corpus (2)

• Deformation and flow of amorphous solids: An updated review of mesoscale elastoplastic models
• Single Particle Brownian Motion with Solid Friction