Title: Directed Self-Assembly of Spheres into a Two-Dimensional Colloidal Crystal by Viscoelastic Stresses
Authors: Pasquino, Rossana ×
Snijkers, Frank
Grizzuti, Nino
Vermant, Jan #
Issue Date: Mar-2010
Publisher: Amer chemical soc
Series Title: Langmuir vol:26 issue:5 pages:3016-3019
Abstract: Ordering induced by shear now can be Used to direct the assembly of particles in Suspensions. Flow-induced ordering is determined by the balance between a range of forces, such as direct interparticle, Brownian, and hydrodynamic forces. The latter are modified when dealing with viscoelastic rather than Newtonian matrices. In particular, 1D stringlike structures of spherical particles have been observed to form along the flow direction in shear thinning viscoelastic fluids, a phenomenon not observed in Newtonian fluids at similar particle volume fractions. Here we report oil the formation of freestanding crystalline patches in planes parallel to the shearing surfaces. The novel microstructure is formed when particles are suspended in viscoelastic, wormlike micellar solutions and only when the applied shear rate exceeds a critical value. In spite of the very low volume fraction (less than 0.01), particles arrange themselves in 2D crystalline patches along the flow direction. This is a bulk phenomenon because 2D crystals form throughout the whole gap between plates, with the gap thickness being much larger than the particle sized Shear flow may hence be all easy method to drive particles into crystalline order in suspensions with visoelastic properties, The crystalline structure reported here Could be used to design new materials with Special mechanical, optical, thermal, or electric properties.
ISSN: 0743-7463
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Soft Matter, Rheology and Technology Section
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science