LOCALIZED AND NONLOCALIZED POLYMER-CHAINS INTERACTING WITH A SURFACE

The conformational properties of a polymer chain interacting with a surface are studied and new features for the cases of a chain free to move in the whole space and for a localized chain fixed with one of its ends at a point are clearly illustrated. The progress achieved is based on exact solutions given in the frame of the continuous model by means of integral equations and Laplace transforms. They permit the study of the behavior of the chain at any distance from the surface as a function of its length, the intensity of the polymer-surface interactions, and the size L of the available space perpendicular to the surface for the nonlocalized chain or the localization position for the localized chain, respectively. The necessary attractions for the gathering of the nonlocalized chains at the surface are larger for larger freedom of the chains which increases with L. From the dependence on the surface-polymer interactions, density profiles are determined for both the depletion and adsorption cases. The behavior of the localized chains is governed by both, the localization constraint and the interactions with the surface.