ADSORPTION OF POLYMERS ON HETEROGENEOUS SURFACES

An extension of a self-consistent-field lattice theory is developed to study the adsorption of polymers on energetically heterogeneous surfa ces. Surface heterogeneity is modeled by introducing distinguishable s urface sites which differ in their interaction energy with polymer seg ments and solvent molecules. The probability for the polymer segments to meet a given kind of site depends on the distribution of the surfac e sites. In this paper, the adsorption behavior of polymers on a surfa ce with adsorbing and nonadsorbing surface sites is studied. For homop olymers, we find that for high chain length and adsorption energy the adsorbed amount is higher on a surface with a random distribution of a dsorbing surface sites as compared to a surface with a patchwise distr ibution, i.e., where equal surface sites are grouped together. Block c opolymers can segregate strongly on a patchwise distributed surface.