Interfacial tension binary polymer blends

SCFT today is one of the most commonly used tools in polymer science. SCFT is based on de Gennes-Edwards description of a polymer molecule as a flexible Gaussian chain combined with the Flory-Huggins "local" treatment of intermolecular interactions. Applications of SCFT include thermodynamics of block copolymers (Bates and Fredrickson, 1999 Matsen and Bates, 1996), adsorption of polymer chains on solid surfaces (Scheutjens and Fleer, 1979,1980), and calculation of interfacial tension in binary polymer blends compatibilized by block copolymers (Lyatskaya et al., 1996), among others. 

DDRM is particularly useful for the binary polymer blends. The dynamic interfacial tension coefficient, Vj2, is determined from the time evolution of a distorted fluid drop toward its equilibrium form. Measurements of either low viscosity model systems or high viscosity industrial polymer mixtures led to a good agreement with values obtained from the widely used breaking thread method. DDRM enables to measure in polymeric blends of commercial interest — the high viscosity systems that frequently are impossible to characterize by other techniques. Furthermore, for the first time it is possible to follow the time dependence of Vj, thus unambiguously determine its dynamic and equilibrium values. 

Effective compatibilization of binary polymer blends by addition of a copolymer should reduce the interfacial tension coefficient. Often, it also alters the molecular structure of the interface (as measured by the scattering methods). The process is similar to the emulsification in the classical emulsions. The emulsifier effect on the droplet size follows generally the same behavior as the interfacial tension. This behavior is described by the emulsification curves (evolution of the particle s size with the emulsifier content) and characterizes the additives efficiency. The shape... 

Genzer, J., Composto, R.J. Effect of molecular weight on the interfacial excess, tension, and width in a homopolymer/binary polymer blend system. Macromolecules 31(3), 870-878 (1998)... 

S.H. Anastasiadis, Interfacial tension in binary polymer blends and the effects of copolymtas as emulsifying agents, in Polymer Thermodynamics. Advances in Polymer Science, vol 238 (2011), p. 179... 

Interfacial Tension in Binary Polymer Blends and the Effects of Copolymers as Emulsifying Agents. 179... 

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