Microscopic interactions and emerging elasticity in model soft particulate gels

TL;DR

This paper models particulate gels with microscopic interactions, revealing how local elastic structures influence the gel's overall elasticity through molecular dynamics simulations and analytical energy estimates.

Contribution

It introduces a model combining two-body attraction and three-body angular repulsion to study gel morphology and elasticity, providing microscopic insights into emergent mechanical properties.

Findings

Varying model parameters samples different gel morphologies.

Identification of local elastic structures within the gel network.

Analytical estimation of elasticity from microscopic interactions.

Abstract

We discuss a class of models for particulate gels in which the particle contacts are described by an effective interaction combining a two-body attraction and a three-body angular repulsion. Using molecular dynamics, we show how varying the model parameters allows us to sample, for a given gelation protocol, a variety of gel morphologies. For a specific set of the model parameters, we identify the local elastic structures that get interlocked in the gel network. Using the analytical expression of their elastic energy from the microscopic interactions, we can estimate their contribution to the emergent elasticity of the gel and gain new insight into its origin.