Fractures in complex fluids: the case of transient networks

TL;DR

This review explores fracture phenomena in transient networks, discussing experimental observations, theoretical models, and the extension of classical fracture concepts to complex viscoelastic fluids.

Contribution

It provides a comprehensive synthesis of experimental and theoretical insights into fracture mechanisms in transient networks, highlighting new criteria for model relevance.

Findings

Experimental fracture behaviors vary across configurations

Theoretical models show conflicting interpretations

Criteria for model applicability are proposed

Abstract

We present a comprehensive review of the current state of fracture phenomena in transient networks, a wide class of viscoelastic fluids. We will first define what is a fracture in a complex fluid, and recall the main structural and rheological properties of transient networks. Secondly, we review experimental reports on fractures of transient networks in several configurations: shear-induced fractures, fractures in Hele-Shaw cells and fracture in extensional geometries (filament stretching rheometry and pendant drop experiments), including fracture propagation. The tentative extension of the concepts of brittleness and ductility to the fracture mechanisms in transient networks is also discussed. Finally, the different and apparently contradictory theoretical approaches developed to interpret fracture nucleation will be addressed and confronted to experimental results. Rationalized criteria to discriminate the relevance of these different models will be proposed.