The energetics of flocculation and redispersion by polymers

Aggregation Processes of a Weak Polyelectrolyte, Poly(allylamine) Hydrochloride

“…Although PAH behaves like particles with aggregated domains, the aggregate maintains a high surface charge on the polyelectrolytes. 12 A polyelectrolyte complex is primarily formed by the strong coulomb interaction between the oppositely charged polyelectrolyte and hydrophobic salt.…”

Contrasting Roles Of Natural Organic Matter On Colloidal Stabilization And Flocculation In Freshwaters

“…The process is most important for polymers which have several points of attachment on the colloidal surface and are large enough to have free segments (loops and tails) outside the zone of electrostatic repulsion such that they are available to bind to other surfaces. The surface coverage of the adsorbed polymer appears to be a fundamental parameter controlling the probability of bridging (La Mer 1966) with the half surface coverage postulated as the optimum condition for flocculation to occur (Healy and La Mer 1964). While flocculation can occur for polymers that are at equilibrium with the colloidal surface (Pelssers et al 1989), non-equilibrium flocculation, occurring before the polymers are able to completely collapse on the colloidal surface, is thought to predominate (Gregory 1988).…”

Effect of Intermittent Addition on Turbidity Removal by Polymer Flocculant: Computer Simulation of Simplified Flocculation Model

“…To explain the flocculation mechanism, several models of bridging between two or more particles by adsorbed polymers have been proposed (Smellie and La Mer, 1958;Healy and La Mer, 1964;Sakohara et al, 1980;Hogg, 1984;Moudgil et al, 1987;Molski, 1989;Elimelech et al, 1995). La Mer and co-workers (Smellie and La Mer, 1958;Healy and La Mer, 1964) expressed bridging flocculation in terms of the fraction of the surface covered by adsorbed polymer. This model can explain experimental results under limited conditions, e.g., low polymer concentration, the initial step of flocculation, etc.…”

“…It is well known that the amount of polymer flocculant adsorbed onto colloidal particles profoundly affects the stability of the colloidal suspension (Fleer and Lyklema, 1974;Ash and Clayfield, 1976;Gregory and Barany, 2011). To explain the flocculation mechanism, several models of bridging between two or more particles by adsorbed polymers have been proposed (Smellie and La Mer, 1958;Healy and La Mer, 1964;Sakohara et al, 1980;Hogg, 1984;Moudgil et al, 1987;Molski, 1989;Elimelech et al, 1995). La Mer and co-workers (Smellie and La Mer, 1958;Healy and La Mer, 1964) expressed bridging flocculation in terms of the fraction of the surface covered by adsorbed polymer.…”