Tension, interfacial demixed polymer

Vrij, A., Equation for the interfacial tension between demixed polymer solutions, J. 

INTERFACIAL TENSION OF DEMIXED POLYMER SOLUTIONS NEAR CRITICAL SOLUTION TEMPERATURE... 

The interfacial tension between demixed liquid phases is one of the important physical properties of polymer solutions and polymer mixtures. In particular, the interfacial tension near critical point is closely related to concentration fluctuations associated with critical opalescence and spinodal decomposition. Recently, some theoretical treatments have been presented for the interfacial tension of demixed polymer solutions and polymer mixtures. For poly-... 

SH1 Shinozaki, K., Abe, M., and Nose, T., Interfacial tension of demixed polymer solutions over a wide range of reduced temperature. Polymer, 23, 722, 1982. 

SC2 Schneider, A. and Wolf, B.A., Interfacial tension of demixed polymer solutions Augmentation by polymer additives, Mactooto/. Rapid Commun., 19, 561, 1997. 

NOS Nose, T. and Tan, T.V., Interfacial tension of demixed polystyrene-methylcyclohexane solution, J. Polym. Sci. Polym. Lett. Ed., 14, 705, 1976. 

Gailard and coworkers [215, 266] demonstrated the surface activity of block copolymers by studying the interfacial tension reduction in demixed polymer solutions. Addition of a FS-b-FBD diblock copolymer to the PS/PBD/styrene ternary system showed first a characteristic decrease in interfacial tension followed by a leveling off, which is similar to the evolution of interfacial tensions for oil-water systems in the presence of surfactants. The early investigations were more of case studies that demonstrated the phenomenon without giving the fundamental detail required to help the understanding of the emulsification process and the factors that govern it. 

The square gradient approach of Cahn and Hilliard" has also been used but can only be tested close to the critical point of the mixture where interfacial tension data are not available. It has, however, been applied to demixed polymer solutions. 

R. L. C. Vink, M. Schmidt (2005) Simulation and theory of fluid demixing and interfacial tension of mixtures of colloids and nonideal polymers. Phys. Rev. E 71, 051406... 

It is known that, in a polymer blend, thermodynamic incompatibility between polymers usually causes demixing of polymers. If the polymer is equilibrated in air, the polymer with the lowest surface energy (hydrophobic polymer) will concentrate at the air interface and reduce the system s interfacial tension as a consequence. The preferential adsorption of a polymer of lower surface tension at the surface was confirmed by a number of researchers for a miscible blend of two different polymers. Based on this concept, surface modifying macromolecules (SMMs) as surface-active additives were synthesized and blended into polymer solutions of polyethersulfone (PES). Depending on the hydro-phobic or hydrophilic nature of the SMM, the membrane surface becomes either more hydrophobic or more hydrophilic than the base polymeric material. ... 

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