Does size matter? Elasticity of compressed suspensions of colloidal- and granular-scale

P. Menut, S. Seiffert, J.H.B. Sprakel, D.A. Weitz

Research output: Contribution to journalArticleAcademicpeer-review

74 Citations (Scopus)

Abstract

We investigate the mechanics of dense packing of very small, colloidal-scale, and larger, granular-scale microgel particles. At low particle concentration, thermally induced Brownian motion of the particles is important for the colloidal-scale systems; in contrast, such Brownian motion is irrelevant at particle packing fractions beyond jamming. As a consequence, colloidal and granular systems behave very similarly under these conditions. At sufficiently high compression of the microgel particles, their polymeric nature sets the scale of the osmotic pressure and shear modulus of the whole packing, in direct analogy with macroscopic, continuous polymer gels. This observation suggests that the particulate nature of microgels is inconsequential for their linear elasticity in a highly packed state. In contrast, the particulate nature of the microgels does become essential when the packed suspensions are forced to yield and flow; here, the differences between colloidal- and granular-scale particles are marked.
Original languageEnglish
Pages (from-to)156-164
JournalSoft Matter
Volume8
Issue number1
DOIs
Publication statusPublished - 2012

Keywords

  • complex fluids
  • rheology
  • emulsions
  • pastes
  • viscoelasticity
  • particles
  • glasses
  • slip

Fingerprint Dive into the research topics of 'Does size matter? Elasticity of compressed suspensions of colloidal- and granular-scale'. Together they form a unique fingerprint.

Cite this