Inverse gas chromatographic characterization of poly(ethylene oxide)

The inverse gas chromatography method was utilized to obtain the thermodynamic properties and the surface energy of a semicrystalline polymer, poly(ethylene oxide) (PEO). PEO was used as a stationary phase in the chromatographic column and 16 solutes with a different chemical nature were used as eluents such as alkanes, acetates and alcohols. Each family has provided information on the type and strength of the PEG-solute interactions. Alkanes showed endothermic interaction parameters chi(12) and the molar heat of mixing in a temperature range of 70-130 degrees C, Acetates and alcohols showed better interactions with the PEO layer and butanol was found to be the best solvent for PEO among all solutes used. The variation in molecular weight of PEO above 4000 g mol(-1) showed no apparent effect on the interaction coefficients. The dispersive contribution of the surface energy of PEO was measured as a function of temperature, which ranged between 8.00 and 13.00 mJ m(-2), indicating a poor surface energy of PEG. (C) 1999 Elsevier Science Ltd. All rights reserved.