Electrokinetic Properties of Polymer Macro-Surfaces

Zusammenfassung

The surface charge of polymer macro-surfaces is a critical parameter for many technical processes. This important material property of films, fibers and granulates can be determined employing streaming potential measurements. The application of this method to irregular formed material is presented. The described method is suitable to characterize the surface of solids by two methods. The isoelectric point can be determined by measuring the pH dependency of the zeta potential and in consequence the pK values of surface groups can be estimated. The number of charged groups and adsorption properties can be determined by measuring the zeta potential as a function of the surfactant concentration in the liquid phase. In consequence either the solid can be characterized with the help of well known surfactants or surfactants can be characterized using well known solids as adsorption matrix. Examples of measurements are presented to demonstrate the use of the method for basic research as well as for the investigation of several important industrial applications.