Adsorption of Polyelectrolyte–Nanoparticle Systems on Silica: Influence on Interaction Forces

Flocculation of reed pulp suspensions by quaternary chitosan‐nanoparticle SiO2retention aid systems

“…However, QCS with high charge density was adsorbed in more extended conformation, polymer chain was in more trains form on the substrates surfaces, and thus the bridging flocculation was fallen. This result was in agreement with the microparticulate retention aid system consisting of cationic polyacrylamide and anionic montmorillonite, 19 and was confirmed by Sennerfors et al, 14 who claimed that it was a 7-fold increase in layer thickness in the presence of nanoparticles for the system with the low-charged CPAM, and a 5-fold increase in thickness in the system consisting of high charged CPAM-SiO 2 .…”

“…This adsorption of a polyelectrolyte to an oppositely charged surface could be seen as an entropy-driven ion-exchange process where counter ions bound to the surface were replaced by the large macro-ions. 14 As a result of the adsorption, the n-potential values of cellulosic fibers were changed. Figure 2 showed the effects of QCS on the n-potential of fibers.…”

“…These complexes reduced the interaction between the segments of polyelectrolyte and substrates surfaces. This could lead some trains on the surfaces of the substrates to rearrange in chain loops and tails, 14 and thus the strong bridging flocculation took place in QCS-SiO 2 system. This phenomenon indicated that QCS-SiO 2 system, as a flocculants system, was expected to be more efficient than QCS system.…”

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

“…The wafers were cleaned in a two-step process, as described elsewhere (13). The wafers were dried in a vacuum and treated in a plasma cleaner, in order to remove impurities, prior to each measurement.…”

“…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.…”