Study of the Dispersive Component of the Surface Energy of Polylactides by Inverse Gas Chromatography at Infinite Dilution

Abstract

Inverse gas chromatography at infinite dilution is a powerful technique that can be advantageously used to characterize the surface physicochemical properties of solid substrates as oxides and polymers in both forms of powder or fibres. In the case of polymer, this technique can be used to determine the second order transition phenomena temperatures. This paper was devoted to the determination of the glass transition temperature of polylactide polymer. The dispersive component of the surface energy of polylactides was determined by inverse gas chromatography at infinite dilution. Various theoretical models were used to deduce the dispersive component of the surface energy of the solid substrates. These models are based on the calculation of the molecular areas of adsorbed molecules on the polymer surface: geometrical model, cylindrical molecular model, liquid density model, BET method, Kiselev results and the two-dimensional Van der Waals and Redlich-Kwong equations. The curves relative to the variation of as a function of the temperature showed a specific graph with a maximum value of at a certain particular temperature characteristic to the investigated polylactide polymer. In fact, the maxima of indicated the presence of glass transition temperature Tg of polylactide whatever the molecular model used. This study showed a glass transition temperature equal to 64°C confirming that obtained by other studies.