THE USEFULNESS OF THE EQUATION OF STATE FOR INTERFACIAL-TENSIONS ESTIMATION IN SOME LIQUID-LIQUID AND SOLID-LIQUID SYSTEMS

Using the values of water-apolar liquid, glycerol-apolar liquid, forma mide-apolar liquid, and ethylene glycol-apolar liquid surface or inter facial tension taken from the. literature, the relationships between p hi parameter of interfacial interactions and interfacial tensions were determined both graphically and mathematically, Next, the so-called ' 'alpha'' and ''beta'' values obtained in this way were used for the so lution of the equation of state for interfacial tensions for liquid-li quid and polymer-liquid systems. The results obtained from the calcula tions have shown that the alpha and beta values are not constant, but depend on the kind of polar-apolar liquid system and the way the value s are determined, The values of alpha and beta differ from 0.0075 and 1, respectively, It has been found that it is impossible to predict th e interfacial tensions of polar-apolar liquids as well as polymer-liqu id systems with good accuracy on the basis of alpha = 0.0075 and beta = 1, and alpha and beta values have also been determined from polar-ap olar liquid interfacial tensions. (C) 1996 Academic Press, Inc.