Colloidal Gels: Equilibrium and Non-Equilibrium Routes

TL;DR

This paper classifies colloidal gels based on their formation routes, emphasizing recent simulation and experimental insights into equilibrium and non-equilibrium gelation mechanisms and their signatures.

Contribution

It provides a framework distinguishing equilibrium and non-equilibrium colloidal gels, linking simulation results to experimental signatures.

Findings

Non-equilibrium gels are linked to thermodynamic phase separation.

Equilibrium gels involve competing interactions and patchy colloids.

Distinct signatures can be identified in experiments for different gel types.

Abstract

We attempt a classification of different colloidal gels based on colloid-colloid interactions. We discriminate primarily between non-equilibrium and equilibrium routes to gelation, the former case being slaved to thermodynamic phase separation while the latter is individuated in the framework of competing interactions and of patchy colloids. Emphasis is put on recent numerical simulations of colloidal gelation and their connection to experiments. Finally we underline typical signatures of different gel types, to be looked in more details in experiments.