POLYMER ADSORPTION: CONCENTRATION EFFECTS.

We consider the various adsorption regimes of flexible chains in a good solvent when the bulk concentration is changed. As the latter is increased, first we find a very dilute bulk regime where the surface coverage increases fast. This is followed by a plateau with much slower increase for GAMMA , the bulk solution being still dilute. In the bulk semi-dilute regime, we consider the adsorption of blobs. For high bulk volume fraction phi //b greater than delta **4**/**3, where delta is the dimensionless excess energy per monomer on the surface, the blobs are not adsorbed. The interfacial tension is calculated in the different regimes. Our approach closely follows the scaling theory of de Gennes and Pincus.