ADVANCES IN
COLLOID AND
INTERFACE
Advances in Colloid and Interface Science SCIENCE
ELSEVIER 67 (1996) 1-118
Electrokinetic properties, colloidal stability and
aggregation kinetics of polymer colloids I
R. Hidalgo-Alvarez a*, A. Martln a, A. Fernandez a, D. Bastos a,
F. Martinez a, F.J. de las Nieves b
aBiocolloid and Fluid Physics Group, Department of Applied Physics, Faculty of Sciences,
Campus Fuentenueva, University of Granada, Granada 18071, Spain
bGroup of Complex Fluid Physics, Department of Applied Physics, Faculty of Sciences,
University of Almeria, Almeria, Spain
Abstract
The purpose of this article is to present some important advances in the electroki-
netic and colloidal characterization of polymer colloids. Special attention is paid to the
new electrokinetic techniques: diffusiophoresis, dielectric dispersion and electro-acous-
tic. Also the most recent theoretical approaches are reviewed with respect to the
electrokinetic properties of polymer colloids. Recently there has been intense discussion
concerning electrokinetic processes and the theories used for data interpretation.
Several concerns have been raised relating to the inability of the different processes and
theories to yield the same electrokinetic potential. The most important explanations
(shear plane expansion, preferential ion adsorption, osmotic swelling, crossing of the
mobility/k-potential and anomalous surface conductance) to the electrokinetic behaviour
of polymer colloids are discussed and analyzed. Also the effect of heat treatment on the
electrokinetic properties of different types of polymer colloids is extensively considered.
With regard to the colloidal stability of polymer colloids, three- and two-dimensional
aggregations are presented. First, the stability factor W is introduced using the classical
theory DLVO and the values obtained of Hamaker constant compared with the theoreti-
cal values estimated from the Lifshitz theory. The differences usually found by several
authors are explained as due to the hydrodynamic interaction. Special attention is paid
1 This review is dedicated to Professor Johannes Lyklema on the occasion of his retirement from
the Physical and Colloid Chemistry Department of the Agricultural University, Wageningen,
The Netherlands
* Corresponding author
0001-8686/96/$32.00 © 1996 -- Elsevier Science B.V. All rights reserved.
PII: S0001-8686(96)00297-7