Gas-Solid Chromatographic Study of Polymer Surfaces - Adsorption on Polystyrene
(EN)
Kontominas, M. G.
(EN)
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας
(EL)
Kontominas, M. G.
(EN)
Inverse gas chromatography (IGC) has been used to construct the adsorption isotherms for a series of n-alkanes on polystyrene in the finite concentration region at 30-degrees. Isotherms for n-heptane were also constructed at 30, 40, 50 and 60-degrees. All isotherms were of type II with a very weak knee, according to the BET classification. Uptake increased with increasing hydrocarbon chain length. Integration of the isotherms gave the spreading pressure (35.5 mN/m) from which the London force component of the polystyrene surface free energy was estimated (55.0 mN/m). N on-dispersive (acid/base) interactions were estimated by exposing the polystyrene surface to acidic and alkaline vapours respectively and calculating the OMEGA interaction parameter. OMEGA values indicated a weakly alkaline polystyrene surface. Adsorption data reflect a relatively high non-specific adsorption potential of the polystyrene surface for the hydrocarbons studied. Calculated, thermodynamic parameters support this finding.
(EN)
