Aging of the Linear Viscoelasticity of Glass- and Gel-forming Liquids

TL;DR

This paper introduces a new theoretical approach based on NESCGLE to predict the zero-shear viscosity of glass- and gel-forming liquids from first principles, successfully matching experimental data.

Contribution

The novel NESCGLE-based method enables first-principles prediction of rheological properties in amorphous materials, advancing understanding of their out-of-equilibrium behavior.

Findings

Excellent agreement between theory and experiment for zero shear viscosity.

Highlights importance of kinetic perspective in modeling amorphous states.

Provides a new framework for interpreting rheological data in viscous liquids.

Abstract

We report a novel approach based on the non-equilibrium self-consistent generalized Langevin equation (NESCGLE) theory that allows for the first principles prediction of the zero-shear viscosity in glass- and- gel-forming materials. This new modulus of the NESCGLE theory facilitates the theoretical description and interpretation of experimental data concerning out-of-equilibrium rheological properties of viscous liquids during their amorphous solidification. The predictive capability of our approach is illustrated here by means of a quantitative comparison between theoretical and experimental results for the zero shear viscosity in suspensions of oligomer-tethered nanoparticles in a polymeric host, finding an almost perfect correspondence between experiments and theory. This comparison also highlights the crucial relevance of including a kinetic perspective, such as that provided by the NESCGLE theory, in the description of dynamic and viscoelastic properties of amorphous states of matter.