Elastic and Yield Behavior of Strongly Flocculated Colloids
نویسندگان
چکیده
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 Derjaguin–Landau–Verwey–Overbeck (DLVO) interactions. Under highly attractive conditions, i.e., in the absence of the secondary minimum in the DLVO potential, the radial (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 observed elasticity in colloidal gels. If r0 and s0 are, respectively, the closest center-to-center and surface-to-surface distances between two particles,
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