Eur. Phys. J. E (2017) 40: 71
https://doi.org/10.1140/epje/i2017-11560-2

Regular Article

Shear-induced slab-like domains in a directed percolated colloidal gel

¹ Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, D-40225, Düsseldorf, Germany
² Institut für Theoretische Physik 1, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91058, Erlangen, Germany

^* e-mail: michael.schmiedeberg@fau.de

Received: 12 May 2017
Accepted: 25 July 2017
Published online: 9 August 2017

Abstract

We explore the structural changes of a gel-forming colloid polymer mixture under shear by employing Brownian dynamics simulations of a colloidal system with short-ranged attractive depletion interaction in a linear flow profile. While the structure of unpercolated systems changes only slightly under shearing, we discover the formation of slab-like clusters in sheared directed percolated gel networks that are confined between two walls. These gel-slabs are stable over a long time and seem to be related to the syneresis phenomena that can be observed in directed percolated colloidal gels. Only at large shear strength the slabs are destroyed and a homogeneous state with many unbounded particles can be observed. We also quantitatively analyze our results by determining void volumes.