Interfacial Tension The theoretical know-how in this area is mainly of phenomenological nature. It concerns the selection of efficient compatibilizers to guarantee a fine dispersion of two immiscible polymers. Other considerations deal with the importance of local and global equilibria for the measurement of interfacial tensions.
Extensive experimental material on the interfacial tension between the coexisting liquid phases of demixed polymer solutions or polymer blends led us to the conclusions that one should be careful with the interpretation of data measured for highly viscous polymer blends. Time independent values do not necessarily represent equilibrium data but may correspond to steady states only. This supposition is based on experiments performed with ternary systems of the type polymer A/polymer B/compatibilizer and on measurements with a blend of two molecularly polydisperse homopolymers C and D. In the former case the interfacial tension resulting for a given composition of the ternary system depends on the polymer to which the compatibilizer is added.
Another area that might be helpful for the understanding of the phenomena and for prac-tical purposes are the scaling laws and master curves established for binary and for ternary mixtures.
For more information, please see the following publications: 228, 216, 198, 188, 186, 182, 177, 161, 152, 127, 125