title: Monolayers of cationic polyelectrolytes on mica--electrokinetic studies.
abstract: Physicochemical properties of cationic polyelectrolytes: poly(allylamine hydrochloride) (PAH), poly(ethylene imine) (PEI), and poly(dimethyldiallylammonium chloride) (PDDA), having molar mass of 70,000, 75,000, and 120,000, respectively, were examined and compared. The bulk characteristics comprised the diffusion coefficient and electrophoretic mobility determined as a function of pH (3.5-9) and ionic strengths (10(-4) M to 0.15 M NaCl). These measurements allowed one to determine theamount of electrokinetic charge of the polyelectrolyte molecules and their isoelectric points. On the other hand, formation of polyelectrolyte monolayers on mica and their properties were investigated using the in situ streaming potential method. Additionally, using this method, the stability of monolayers, evaluated via desorption kinetic measurements, was determined. The investigations showed that PAH molecules form the most stable monolayers, which can be used as supporting layers for particle deposition and multilayer formation.
authors.affiliation: Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239 Cracow, Poland. ncmorga@cyf-kr.edu.pl
authors.forename: Maria
authors.initials: M
authors.lastname: Morga
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Adamczyk
keywords: Deposition kinetics at heterogeneous surfaces; Electrokinetic characteristics of polyelectrolytes; Electrokinetics of particle covered surfaces, adsorption of polyelectrolytes on mica; PAH, PEI, PDDA adsorption on mica; Streaming potential measurements; Supporting monolayer surface characteristics; The dependence of surface zeta potential of PAH, PEI, and PDDA on ionic strength; Zeta potential of heterogeneous surfaces