POLYMER ADSORPTION AT LIQUID AIR INTERFACES UNDER LATERAL PRESSURE

We present calculations of surface tension of absorbed polymer solutio ns at the liquid/air interface. Lateral changes in the area per monome r on the surface are induced by changing the surface pressure (lateral compression), while keeping the total surface excess fixed. Lateral c ompression of the adsorbed layer immersed in a good solvent results in an increase in the surface monomer concentration and surface pressure up to a critical area per monomer value where the compressibility of the system vanishes. Our mean-field model is not appropriate to descri be more compressed states. Calculations are repeated in theta and bad solvent conditions, and yield similar behavior of the isotherms.