Highly Charged Cationic Polyelectrolytes on Mica: Influence of Polyelectrolyte Concentration on Surface Forces

The Effect of Salt Concentration on Adsorption of Low-Charge-Density Polyelectrolytes and Interactions between Polyelectrolyte-Coated Surfaces

“…In low ionic strength solutions (around 0.1 mM) the adsorption of the polyelectrolyte (together with that of small ions) leads to an almost uncharged surface. Force curves obtained for poly-(MAPTAC) ( ϭ 100%) (19) and the structurally similar PCMA (54) have been shown to be insensitive to the molecular weight of the polyelectrolyte as a consequence of the high polyelectrolyte-surface affinity which results in a very thin adsorbed layer (in agreement with theoretical models (9)). The long-range force is dominated by a strong bridging attraction below about 15 nm.…”

“…2.5 mg/m 2 is actually adsorbed, i.e., only 10% of the small cations initially adsorbed are exchanged. In contrast, Dahlgren et al (54) found that upon addition of a 100% charged polyelectrolyte the mica lattice charge was fully compensated (complete ion exchange) by the charges on the polyelectrolyte. We are currently investigating to what extent the surface lattice charge of mica is neutralized by adsorbing polyelectrolytes of intermediate charge densities.…”

“…The forces acting between mica surfaces coated with cationic acrylamides of various charge densities have been investigated in a series of papers (18,19,21,22,24,25,28,54,59). In low ionic strength solutions (around 0.1 mM) the adsorption of the polyelectrolyte (together with that of small ions) leads to an almost uncharged surface.…”

The Effect of a Cationic Polyelectrolyte on the Forces between Two Cellulose Surfaces and between One Cellulose and One Mineral Surface

“…The long-range steric force observed on the first approach suggests, however, that some PCMA chains extend quite far out into the solution. This has also been observed to be the case when PCMA overcompensates the surface charge on bare mica surfaces (28). Allowing the adsorption to equilibrate for another 7 h did not change the interaction forces.…”

Adsorption of Polyelectrolyte–Nanoparticle Systems on Silica: Influence of Ionic Strength

“…Other central parameters include the pH, the solution ionic strength, and the particle and polymer concentrations. Several studies have been concerned with the forces acting between adsorbed polyelectrolyte layers (10)(11)(12) as well as between composite layers of polyelectrolyte and particles (3,13). The effect of the ionic strength of the ambient media on the adsorption (14-18) and interactions in polyelectrolyte solutions (11,16,(19)(20)(21) has been the subject of several studies.…”