Summary: Elastic and Yield Behavior of Strongly Flocculated Colloids
Wan Y. Shih,,
Wei-Heng Shih,*,
and Ilhan A. Aksay*,
Department of Chemical Engineering and Princeton Materials Institute, Princeton University,
Princeton, New Jersey 08544-5263; and
Department of Materials Engineering, Drexel University, Philadelphia, Pennsylvania 19104-2875
We have investigated theorectically the elastic and yield
behaviors of strongly flocculated colloids by first examining
the yield forces between two particles within the framework
of Derjaguin­Landau­Verwey­Overbeck (DLVO) interac-
tions. Under highly attractive conditions, i.e., in the absence
of the secondary minimum in the DLVO potential, the ra-
dial (tensile) motion between particles is nonelastic because
of the lack of an inflection point in the DLVO potential.
However, the lateral (shear) motion is shown to be elastic
up to a distance ymax, providing a mechanism for the ob-
served elasticity in colloidal gels. If r0 and s0 are, respec-
tively, the closest center-to-center and surface-to-surface
distances between two particles,

Source: Aksay, Ilhan A. - Department of Chemical Engineering, Princeton University

Collections: Materials Science