concentration. According to the DLVO theory (1-3), the An investigation into the effects of interfacial properties on the stability of colloidal dispersions is determined by two particolloidal stability of monodisperse polymer colloids using two sulcle interaction energies, repulsive (V R ) and attractive (V A ). fate polystyrene latexes is presented. Both latexes were prepared The net interaction energy (V ) is given by the algebraic sum by emulsion copolymerization in the absence of surfactant. The of the two (V R / V A ). V R is due to the overlap between the experimental stability of these colloidal dispersions was studied in diffuse double layers of the particles and decays approxirelation to the concentration (C e ) of an indifferent electrolyte.
mately exponentially with the distance of separation. V A is
Results are compared to current models, relating the stability ratio due to the London-van der Waals (dispersion) energy and (W ) to intermolecular forces between particles. The Hamaker constant (A) obtained from the log W -log C e plots, using the DLVO decays according to a power law. Since V R is sensitive to theory, is much lower than the theoretical value given by the the electrolyte concentration while V A is not, the stability of Lifshitz theory. In order to achieve good agreement between the colloidal dispersions can be controlled by changing the ionic experimental and theoretical A values, different corrections to the strength of the solution.
DLVO theory were introduced as the hydrodynamic effect and
Up until the mid-1980s, it was found that the stability of the size of the hydrated ions. When the nonionic surfactants Triton polymer colloids with polyelectrolytes or ionic surfactants X-100, Triton X-165, Triton X-305, and Triton X-405 were adadsorbed onto the particle surface is also affected by electrosorbed onto both latexes a new correction was made to the DLVO static and steric effects. The combined effect of these two theory: the effect of electrosteric stabilization. Including the elasmechanisms is known as electrosteric stabilization (4-6). tic-steric effect and the osmotic potential, five parameters are involved in the total interaction energy. By using well-known lamation of the surfactant on the latex surface via the values of the mation. Besides, the stabilization of surfactant-latex comvolume fraction of segment in the external regions. ᭧ 1998 Academic plexes can be used as a alternative method to analyze the Press conformation of the surfactant on the surface.