Interpretation of the chromatographic behavior of perhydrogenated and perfluorinated polyoxyethylene surfactants by molecular modeling

Neutral perhydrogenated and perfluorinated polyoxyethylene surfactants have been analyzed by reversed-phase liquid chromatography with methanol-water mobile phases in which the volume fraction of methanol was varied between 0 .75 and 0.10. The amphiphilic behavior of these materials was compared and related to the length of the perhydrogenated or perfluorinated alkyl chain, the number of oxyethylene residues, and the presence of an oxygen or sulfu r atom in the molecule. To obtain deeper insight quantitative structure-ret ention relationships were investigated. Molecular electrostatic potential, molecular lipophilic potential, the logarithm of the calculated partition c oefficient between water and octanol, and the molecular volume were found t o be good descriptors with satisfactory statistical significance.