The Primary Electroviscous Effect in Polystyrene Latices of Small Particle Size Range Prepared with the Addition of Anionic Surfactant as Emulsifier. Effect of Increasing Concentrations of Quaternary Ammonium Counterions of Different Ionic Sizes and Stability Characteristic of the Latices and the Latex–Electrolyte Mixtures

Abstract

Polystyrene latices were prepared by the emulsion polymerization method using hydrogen peroxide as an initiator and sodium dodecyl sulfate as the emulsifying agent. Latices of different particle sizes were prepared by the seeded growth technique. The particle size and its frequency distribution were determined by electron microscope. The viscosities and electrophoretic mobilities of the latex and latex:added electrolyte mixtures were measured in the presence of gradually increasing concentrations of quaternary ammonium counterions of different ionic sizes. The ζ-potentials were calculated by the computational method of Wiersema–Loeb– Overbeek (WLO); the surface charge densities σ were calculated by the method of Loeb–Wiersema–Overbeek (LWO). The primary electroviscous effects were calculated by using the Booth equation. The free energies of adsorption ΔḠadsof the counterions on the particle surface were calculated. The stability characteristic of the latices and latex–added electrolyte mixtures has been studied on the basis of the DLVO theory.