A gas‐chromatographic investigation of the thermodynamics of solutions of some normal and branched alkanes, cyclohexane, benzene and tetrachloromethane in polyisobutylene

Abstract

AbstractFrom net retention volumes, measured over a wide range of temperatures, solute molar volumes and solute fugacities, standard partial molar free enthalpies, entropies and enthalpies of mixing at infinite dilution in polyisobutylene solution were calculated over a range of temperatures.Gas‐chromatography is an unique method in the sense that it gives thermodynamic data at polymer mole fractions near unity whereas conventional methods usually are not capable of giving accurate data for very concentrated polymer solutions.The residual standard partial molar free enthalpies and entropies and the standard partial molar enthalpies of mixing of the normal and branched alkanes were analysed by the (simplified) Prigogine solution theory. Those of the n‐alkanes, cyclohexane, benzene and tetrachloromethane were discussed in terms of the solution theory of Flory, Orwoll and Vrij.