Conformational properties and the entropic barrier in the “head-on” adsorption of a single polymer chain towards a flat surface

This work investigates the change in conformations and the entropic free energy barrier in the "head-on" adsorption process of a flexible polymer chain towards a flat surface in the framework of the Gaussian chain model. Analytical expressions are reported for the distribution of chain end, the mean square end-to-end distance, the entropic free energy barrier and the adsorption equilibrium constant at low surface coverage (the "mushroom" regime). Theoretical results are discussed in the context of polyoxyethylene-phosphonate-type polymer dispersants, possessing a non-adsorbing polyoxyethylene chain and an adsorbing head-group.