We study adsorption-desorption kinetics of polymer chains at a solid surface. Protio polystyrene, adsorbed from cyclohexane to a single surface of oxidized silicon, was displaced by deuterio polystyrene. A single time constant, τoff, described displacement for a significant time (1-2 h). An aging effect, in which τoff continued to increase even after mass adsorbed had equilibrated, implied surprisingly slow rearrangements of adsorbed chains in the direction of conformational equilibrium. After equilibration, τoff increased exponentially with length of adsorbed chains.
ASJC Scopus subject areas
- Physics and Astronomy(all)