Probing chain ends in adsorbed polymer layers

We study theoretically the pull-out of polymer chains from an adsorbed polymer layer by sticking of the chain ends on an opposing surface using scaling arguments and a mean field theory. When only one chain is pulled out from the layer, we extend previous results obtained for a single adsorbed chain and calculate the force necessary to extract the chain from the layer. We then discuss end adsorption from an adsorbed layer of polymers bearing specific end groups onto a second surface. Two bridging regimes are predicted: a diffuse layer regime at weak separations (or/and weak interaction) and a large separation strong interaction regime where the bridges stretch into a brush like structure. Bridging fractions and force profiles are displayed that could be compared to atomic force microscope or surface force apparatus experiments.