ADSORPTION OF SEMIFLEXIBLE POLYMERS

The self-consistent-field model for polymer adsorption of Scheutjens a nd Fleer is extended to the case of semiflexible chains in a cubic lat tice. It is found that the scaling behavior for adsorption from a dilu te solution of polymers with the same radius of gyration, but with a v arying degree of stiffness, is markedly different. Adsorption from a s emidilute solution gives a chain-length-independent profile, even when bond correlations are taken into account. Adsorbing block copolymers with blocks that differ only in the rigidity of the blocks adsorb with the stiffer block on the surface. This preference has an entropical o rigin. Such copolymers behave similar to ''energetic'' block copolymer s, where the blocks differ in energetic interaction with the solvent o r with the surface. The effects of chain stiffness are of the same ord er of magnitude as energetic effects.