Multi-component colloidal gels: interplay between structure and mechanical properties

Claudia Ferreiro-Cordova, Giuseppe Foffi (LPS) Mehdi Bouzid (LPTMS)

Gels are very present in your daily life; the shampoo that you wash your hair with, the gelatine in your mince pies, or your toothpaste. In these examples, the gel is composed of a large amount of liquid which is entrapped in a three-dimensional network of molecules such as surfactants or polymers. Although their liquid content is much larger than their solid content, gels present solid-like mechanical properties such as the presence of an elastic regime at low strain. There is a particular type of gel where this network, instead of being formed by a sequence of molecules, is formed by chains of tiny solid particles (colloids). These are known as colloidal gels.

Snapshots of arrested phases for monogel, bigel and trigel. The interactions (attractive or repulsive) are also depicted for each specie

In this project, the authors present a thorough numerical study where they model the formation of colloidal gels whose networks are composed of up to three different types of particle chains. Moreover, they correlate the resulting structures with their mechanical properties, enabling the authors to establish predictions on the performance of these gels for different applications.  The insights presented in this work are of high relevance not only to advance the understanding of colloidal gels but also to the design of novel soft materials with tailored mechanical properties.

C. Ferreiro-Córdova, E. Del Gado, G. Foffi and M. Bouzid. Multi-component colloidal gels: interplay between structure and mechanical, Soft Matter, 16, 4414-4421 (2020). DOI: 10.1039/C9SM02410G.

Results obtained within the project MUSA coordinated by Giuseppe Foffi