Contact and macroscopic ageing in colloidal suspensions - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Nature Materials Année : 2020

Contact and macroscopic ageing in colloidal suspensions

Francesco Bonacci
Xavier Chateau
Jennifer Fusier
  • Fonction : Auteur
  • PersonId : 782816
  • IdRef : 202414663
Julie Goyon
Anaël Lemaître

Résumé

The aging behaviour of dense suspensions or pastes at rest is almost exclusively attributed to structural dynamics. Here, we identify another aging process, contact-controlled aging, consisting in the progressive stiffening of solid-solid contacts, after their initial formation rapidly arrests the microstructure. By combining rheometry, confocal microscopy, and particle-scale mechanical tests using laser tweezers, we demonstrate that this process governs the shear modulus aging of dense aqueous silica and polymer latex suspensions at moderate ionic strengths. We further show that contact-controlled aging becomes relevant as soon as Coulombic interactions are sufficiently screened out that the formation of solid-solid contacts is not limited by activation barriers. Given that this condition only requires moderate ion concentrations, contact-controlled aging should be generic in a wide class of materials, such as cements, soils, or 3D inks, thus questioning our understanding of aging dynamics in these systems.
Fichier principal
Vignette du fichier
contacts3.pdf (2.61 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-02938734 , version 1 (15-09-2020)

Identifiants

Citer

Francesco Bonacci, Xavier Chateau, Eric M Furst, Jennifer Fusier, Julie Goyon, et al.. Contact and macroscopic ageing in colloidal suspensions. Nature Materials, 2020, 19 (7), pp.775-780. ⟨10.1038/s41563-020-0624-9⟩. ⟨hal-02938734⟩
69 Consultations
351 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More