Theory of polyelectrolytes in solutions and at surfaces

Polyelectrolytes are polymers carrying either positively or negatively charged ionizable groups. The properties of these polymers in solutions and at charged surfaces depend on the fraction of dissociated ionic groups, solvent quality for polymer backbone, solution dielectric constant, salt concentration, and polymer-substrate interactions. In this review, we summarize the current development of theoretical models describing properties of polyelectrolyte solutions and adsorption of charged polymers at surfaces and interfaces. We discuss in detail the conformational properties of polyelectrolyte chains in dilute and semidilute solutions, the phenomenon of counterion condensation, the necklace structure of polyelectrolytes in poor solvent conditions for polymer backbone, the dynamics of polyelectrolyte solutions, the surface overcharging by adsorbed polyelectrolytes and its implication for assembled polyelectrolyte multilayers. (c) 2005 Elsevier Ltd. All rights reserved.