Stability of Polyvinyl Chloride Latices
Among the important contributions to polymer technology, the invention of the emulsion polymerization process has been recognized to be of outstanding value. The salient feature of this process is that the reaction exists, almost exclusively, in small particles, generally less than one micron in diameter, which are dispersed in water. This reaction results in rapid polymerization rates coupled with the attainment of usefully high molecular weights in the final product. Another characteristic property of the emulsion polymerization process is the utilization of surfactants, which serve a dual purpose. As has been shown by Harkins (1), the surfactant micelles serve as the loci of the polymerization, while simultaneously preventing the flocculation of the particles which have been produced. The degree to which the surfactant stabilizes a latex is a direct function of the surfactant’s chemical composition, its adsorptivity on the particle surface, its degree of ionization at the surface, and the kind and concentration of the salts present in the bulk solution. It is the objective of this work to establish latex colloidal stability as a function of surfactant concentration, and electrolyte environment, and to interpret the results with the use of current theories.
KeywordsMethylene Blue Electric Double Layer DLVO Theory Critical Coagulation Concentration Rapid Coagulation
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