COLL 184 |
| Susan E. Burke and Christropher J. Barrett. Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A 2K6, Canada |
| The acid-base equilibria of weak polyelectrolytes absorbed on a surface were shown to differ significantly from their dilute solution values. A series of multilayer thin films was prepared using either poly(allylamine hydrochloride) and poly(acrylic acid) or poly(L-lysine hydrochloride) and hyaluronic acid, and the dissociation behavior of the film surface was investigated for its dependence on the number of underlying polyelectrolyte layers and variations in the charge density of the film with pH. In addition, the shifts in acid-base equilibria were used to explain the strong dependence of the physico-chemical properties of the film (i.e. film thickness, swelling properties, contact angle, and surface friction) on the local pH environment. Although the trends in the dissociation constants are specific to the polyelectrolyte combination making up the film, it is apparent that the shifts in the acid-base equilibria of the polyelectrolytes have a significant influence on the film properties.
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Adsorption of Macromolecules at Liquid-Solid Interfaces
Division of Colloid and Surface Chemistry |