Osmotically driven shape-dependent colloidal separations

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Revision as of 19:56, 12 April 2009 by Lidiya (Talk | contribs) (Abstract)

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by Lidiya Mishchenko


Mason, T.G. Physical Review E 66, 060402(R) 2002


Osmotic pressure, entropy, assembly, micelle, colloid, excluded volume


"The thermally induced motion of nanometer-sized surfactant micelles in water is used to create strong attractive forces between micron-sized disks of wax in a mixed aqueous dispersion of microdisks and microspheres. The short-ranged attractive force due to the depletion of micelles from between the microdisks is much stronger than that between two microspheres of similar size, and is largest when the disks approach face to face, so columns of microdisks form. These columns cream, whereas the spheres remain dispersed, providing a means for shape-dependent colloidal separations driven by an applied micellar osmotic pressure."

Soft Matter Example

Excluded volume (shown in yellow) between particles of different geometries. Purple particles are micelles (not to scale)