Critical Experimental Comparison between Five Techniques for the Determination of Interfacial Tension in Polymer Blends: Model System of Polystyrene/Polyamide-6

A critical review and experimental comparison between different techniques for the determination of interfacial tension are presented for a model polymer pair. Five experimental methods were applied to measure the interfacial tension for the model pair of polystyrene (PS) and polyamide-6 (PA-6) at the same temperature. The techniques include three dynamic methods (the breaking thread method, the imbedded fiber retraction method, and the retraction of deformed drop method), one equilibrium method (the pendant drop method), and a rheological method based on linear viscoelastic measurements. The advantages, the limitations, and the difficulties of each technique are discussed and compared.