The adhesion of polymers on a solid surface.

The specific properties of polymers are often disregarded in theories of adhesion, but they have an essential function for the strength of the adhesive bond. Polymers are repelled entropically from impenetrable surfaces by the depletion effect. To bond them to the substrate, polymer molecules must be forced actively towards the interface. This suppression of depletion is by adsorption of specific polar groups, which interact with polar sites on the substrate. Adsorption diminishes the effective distance between the surface and the adhesive polymer. The balance between adsorption and depletion, and not the effect of polar groups or pre-treatments on the ''work of adhesion'', is the most important chemical possibility to increase the strength of the adhesive bond between polymers and solid surfaces.