Attractive double-layer forces and charge regulation upon interaction between electrografted amine layers and silica

Dunér, Gunnar; Iruthayaraj, Joseph; Daasbjerg, Kim; Pedersen, Steen Uttrup; Thormann, Esben; Dédinaité, Andra

doi:10.1016/j.jcis.2012.06.071

Cited by 11 publications

(13 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Electric Double Layer Forces Between Polydadmac Layers Meassupporting

confidence: 91%

“…For the saturated layers of polyDADMAC, this implies overcompensation of the surface charge and hence charge reversal resulting in net positively charged surfaces which is consistent with many previous reports. 26,33 It is however, interesting that the sign of the net charge of surface layers reverses back to the negative value when the pH is increased and an unsaturated polyDADMAC layer is obtained. When the pH increased from 3 to 5.6, the adsorbed amount of polyDADMAC is fixed (and thus the amount of positive charges is fixed), but the silica substrate turns more negative due to dissociation of silanol groups resulting in an overall charge reversal from positive to negative.…”

Section: Resultsmentioning

confidence: 99%

“…For a more detailed discussion on how to derive the theoretical force curves from the nonlinear Poisson−Boltzmann equation, we refer to the previous work. 26 However, from the nonlinear Poisson−Boltzmann equation, the double-layer pressure between two flat surfaces, ΔP, is obtained and can subsequently be converted to the free energy of interaction per unit area, ΔG, by…”

Section: Methodsmentioning

confidence: 99%

“…where ψ is the double layer potential, x is the position of a plane of equal potential away from a flat surface, e is the elementary charge, ρ∞ is the background salt concentration (number density), ε is the dielectric constant of the solution between the interacting surfaces, ε0 is the permittivity of vacuum, and z is the ion valance (which is 1 in this case). For a more detailed discussion on how to derive the theoretical force curves from the non-linear Poisson-Boltzmann equation we refer to the previous work 26 . However, from the non-linear Poisson-Boltzmann equation, the double layer pressure between two flat surfaces, ΔP, is obtained, and can subsequently be converted to the free energy of interaction per unit area, ΔG, by:…”

Section: Quartz Crystal Microbalance With Dissipation (Qcm-dmentioning

confidence: 99%

See 3 more Smart Citations

Surface Forces between Highly Charged Cationic Polyelectrolytes Adsorbed to Silica: How Control of pH and the Adsorbed Amount Determines the Net Surface Charge

2018

Self Cite

View full text Add to dashboard Cite

Atomic force microscopy (AFM) and quartz crystal microbalance with dissipation (QCM-D) were employed to investigate the pH-dependent adsorption of poly(diallyldimethylammonium chloride) (polyDADMAC) to silica surfaces as well as the surface forces between these layers. It was found that polyDADMAC adopted a relatively flat conformation when adsorbed to a silica surface and that the adsorbed amount increased with increasing pH. From the surface force measurements it is evident that the surface undergoes a charge reversal upon saturation with polyDADMAC, at the three different investigated pH values, and that some degree of charge regulation of the silica surface takes place during the adsorption process. Finally, the overcharging phenomenon is discussed in terms of a geometrical mismatch due to the different average spacing between the surface charges on the silica surface and the size of the DADMAC monomer.

show abstract

Section: Electric Double Layer Forces Between Polydadmac Layers Meassupporting

confidence: 91%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Quartz Crystal Microbalance With Dissipation (Qcm-dmentioning

confidence: 99%

See 2 more Smart Citations

Surface Forces between Highly Charged Cationic Polyelectrolytes Adsorbed to Silica: How Control of pH and the Adsorbed Amount Determines the Net Surface Charge

2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…The procedure for these calculation is described in detail elsewhere. 28 In addition to the electrical double-layer force, the van der Waals force between the spherical probe and the flat surface was calculated as 10…”

Section: Dlvo Calculationsmentioning

confidence: 99%

Electrical Double-Layer and Ion Bridging Forces between Symmetric and Asymmetric Charged Surfaces in the Presence of Mono- and Divalent Ions

et al. 2017

Self Cite

View full text Add to dashboard Cite

An atomic force microscope, employing the colloidal probe technique, was used to study the interactions between six different combinations of silane-functionalized silica surfaces in NaCl and CaCl solutions. The surfaces consisted of monolayers of the apolar trimethoxy(octyl)silane, the positively charged (3-aminopropyl)trimethoxysilane, and the negatively charged (3-mercaptopropyl)trimethoxysilane. The interactions between the three symmetric systems, as well as between the three asymmetric combinations of surfaces, were measured and compared to calculated electrical double-layer forces. The results demonstrated that the long-range interactions between the surfaces in all cases were dominated by double-layer forces, while short-range interactions, including adhesion, were dominated by ion bridging forces in the cases where both interaction surfaces favored adsorption of calcium ions. The study thus also demonstrates how surface force studies in mono- and divalent salt solutions can be used as an analytical tool for probing specific functional groups on heterogeneous surfaces.

show abstract

Tracking colloidal silica particles to evaluate their dispersion and interactions in concentrated suspensions under shear force applications

Saeed,

Otsuki,

Hermes

et al. 2024

Electrophoresis

View full text Add to dashboard Cite

This study aimed to characterize interactions within colloidal silica particles in their concentrated suspensions, using rheo‐confocal measurements and imaging, followed by image analysis. We studied the effect of shear rate (0–500 s–1) and solution pH (6, 10) on the dispersion degree of colloidal silica particles via the determination and comparison of interparticle distances and their modeling. Images corresponding to different shear rates were analyzed to identify the coordinates of the particles. These coordinates were further analyzed to calculate the distance among the particles and then their surface‐to‐surface distance normalized by the particle diameter (H/D). It was found that the population of the particles per unit area of the image and H/D varied with increasing shear rate. The comparison between experimentally measured and theoretically calculated H/D identified that for some particles, the former was shorter than the latter, indicating the unexpected attractions among them against the Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. Then, the modification of previously reported equations for H/D was suggested and confirmed its validity. Assuming pair potential interaction and hydrodynamic interaction were the main non‐DLVO interactions, their magnitudes were calculated and confirmed the significance of pH and shear application strength on particle dispersion/coagulation.

show abstract

Attractive double-layer forces and charge regulation upon interaction between electrografted amine layers and silica

Cited by 11 publications

References 62 publications

Surface Forces between Highly Charged Cationic Polyelectrolytes Adsorbed to Silica: How Control of pH and the Adsorbed Amount Determines the Net Surface Charge

Surface Forces between Highly Charged Cationic Polyelectrolytes Adsorbed to Silica: How Control of pH and the Adsorbed Amount Determines the Net Surface Charge

Electrical Double-Layer and Ion Bridging Forces between Symmetric and Asymmetric Charged Surfaces in the Presence of Mono- and Divalent Ions

Tracking colloidal silica particles to evaluate their dispersion and interactions in concentrated suspensions under shear force applications

Contact Info

Product

Resources

About