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Polyelectrolytes near like-charged substrates in the presence of multivalent ions

English title Polyelectrolytes near like-charged substrates in the presence of multivalent ions
Applicant Borkovec Michal
Number 159874
Funding scheme Project funding
Research institution Département de Chimie Minérale et Analytique Université de Genève
Institution of higher education University of Geneva - GE
Main discipline Physical Chemistry
Start/End 01.06.2015 - 31.05.2018
Approved amount 730'000.00
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All Disciplines (2)

Discipline
Physical Chemistry
Material Sciences

Keywords (5)

surface forces; atomic force microscopy; polyelectrolytes; adsorption; multivalent ions

Lay Summary (German)

Lead
Das Projekt untersucht Wechselwirkungen zwischen Polyelektrolyten und gleich geladenen festen Substraten in Gegenwart von mehrwertigen Ionen. Solche Systeme werden in verschiedenen Anwendungen eingesetzt, wie zum Beispiel in der Wasseraufbereitung oder der Mineralverarbeitung. Das vorliegende Projekt wird die zugrundeliegenden Mechanismen dieser Verfahren klarzustellen, und das Wechselwirkung von gut-definierten Polyelektrolyten mit gleichgeladenen Substraten in Gegenwart von mehrwertigen Ionen zu konzentrieren. Dabei werden Lösungseigenschaften durch Lichtstreuung untersucht, Adsorption der Polyelektrolyte durch Reflexionstechniken und Wechselwirkungskräfte zwischen solchen Substraten durch Kraftmikroskopie untersucht werden.
Lay summary

Das Projekt untersucht Wechselwirkungen zwischen geladenen Polymeren, sogenannten  Polyelektrolyten, und festen Substraten. Bei verschiedenen Anwendungen kommen oft negativ geladene Substrate vor, und die verwendeten Polyelektrolyte weisen ebenso eine negative Ladung auf. Obwohl man erwarten würde, dass in einer solchen Situation die Polyelektrolyte mit dem Substrat kaum wechselwirken, können solche Wechselwirkungen durch Zugabe von mehrwertigen Ionen induziert werden. Beispielsweise trifft man diese Situation in der Wasseraufbereitung an. Negativ geladene Ton-Teilchen können aus dem Abwasser durch Zugabe von negativ geladenen Polyelektrolyten und von einem Eisensalz entfernt werden. Die Eisen-Ionen fördern die Adsorption von Polyelektrolyten, was eine Bildung von großen Teilchenaggregaten induziert, die dann durch Sedimentation abgetrennt werden können. Das vorliegende Projekt zielt darauf ab, den Mechanismus dieser Vorgänge zu klären, und die Wechselwirkungen zwischen gut-definierten Polyelektrolyten mit gleichgeladenen Substraten in Gegenwart von mehrwertigen Ionen zu untersuchen. Dabei werden Lösungseigenschaften durch Lichtstreuung untersucht, Adsorption der Polyelektrolyte durch Reflexionstechniken, und Wechselwirkungskräfte zwischen solchen Substraten durch Kraftmikroskopie. Die Ergebnisse des Projekts werden in der wissenschaftlichen Forschung wie auch in der Industrie von Bedeutung sein.

Direct link to Lay Summary Last update: 30.03.2015

Lay Summary (English)

Lead
The project investigates interactions between polyelectrolytes and like-charged solid substrates in the presence of multivalent ions. Such systems are used in various applications, such as water treatment or mineral processing. The present project will clarify the underlying mechanism of these processes, and will focus on the interaction of well-defined polyelectrolytes with like-charged substrates in the presence of multivalent ions. In particular, solution properties will be investigated by light scattering, adsorption of the polyelectrolytes by reflectivity techniques, and interaction between such substrates by atomic force microscopy.
Lay summary

The project focuses on interactions between charged polymers, so-called polyelectrolytes, and solid substrates. In various applications, the substrates are negatively charged and the polyelectrolytes equally bear a negative charge. While one would expect that the polyelectrolytes do not interact with the substrate, such interactions can be induced by adding multivalent ions. One encounters this situation in water purification, for example. One can removes negatively charged clay particles from waste water by adding negatively charge polyelectrolytes and an iron salt. The iron ions promote the adsorption of the polyelectrolytes, inducing formation of large particle aggregates, which can then be separated by sedimentation. The present project aims to clarify of the mechanism of these processes, and will study interaction of well-defined polyelectrolytes with like-charged substrates in the presence of multivalent ions. In particular, solution properties will be investigated by light scattering, adsorption of the polyelectrolytes by reflectivity techniques, and interaction between such substrates by atomic force microscopy. The project results are expected to have impact in academia and industry.

Direct link to Lay Summary Last update: 30.03.2015

Responsible applicant and co-applicants

Employees

Publications

Publication
Attractive non-DLVO forces induced by adsorption of monovalent organic ions
Smith Alexander M., Maroni Plinio, Borkovec Michal (2018), Attractive non-DLVO forces induced by adsorption of monovalent organic ions, in Physical Chemistry Chemical Physics, 20(1), 158-164.
Interactions between similar and dissimilar charged interfaces in the presence of multivalent anions
Moazzami-Gudarzi Mohsen, Adam Pavel, Smith Alexander M., Trefalt Gregor, Szilágyi István, Maroni Plinio, Borkovec Michal (2018), Interactions between similar and dissimilar charged interfaces in the presence of multivalent anions, in Physical Chemistry Chemical Physics, 20(14), 9436-9448.
Colloidal Stability in Asymmetric Electrolytes: Modifications of the Schulze–Hardy Rule
Trefalt Gregor, Szilagyi Istvan, Téllez Gabriel, Borkovec Michal (2017), Colloidal Stability in Asymmetric Electrolytes: Modifications of the Schulze–Hardy Rule, in Langmuir, 33(7), 1695-1704.
Forces between colloidal particles in aqueous solutions containing monovalent and multivalent ions
Trefalt Gregor, Palberg Thomas, Borkovec Michal (2017), Forces between colloidal particles in aqueous solutions containing monovalent and multivalent ions, in Current Opinion in Colloid & Interface Science, 27, 9-17.
Depletion and double layer forces acting between charged particles in solutions of like-charged polyelectrolytes and monovalent salts
Moazzami-Gudarzi Mohsen, Maroni Plinio, Borkovec Michal, Trefalt Gregor (2017), Depletion and double layer forces acting between charged particles in solutions of like-charged polyelectrolytes and monovalent salts, in Soft Matter, 13(18), 3284-3295.
Heteroaggregation of oppositely charged particles in the presence of multivalent ions
Cao Tianchi, Sugimoto Takuya, Szilagyi Istvan, Trefalt Gregor, Borkovec Michal (2017), Heteroaggregation of oppositely charged particles in the presence of multivalent ions, in Physical Chemistry Chemical Physics, 19(23), 15160-15171.
Interplay between Depletion and Double-Layer Forces Acting between Charged Particles in Solutions of Like-Charged Polyelectrolytes
Moazzami-Gudarzi Mohsen, Kremer Tomislav, Valmacco Valentina, Maroni Plinio, Borkovec Michal, Trefalt Gregor (2016), Interplay between Depletion and Double-Layer Forces Acting between Charged Particles in Solutions of Like-Charged Polyelectrolytes, in Physical Review Letters, 117(8), 088001-088001.
Forces between silica particles in the presence of multivalent cations
Valmacco Valentina, Elzbieciak-Wodka Magdalena, Herman David, Trefalt Gregor, Maroni Plinio, Borkovec Michal (2016), Forces between silica particles in the presence of multivalent cations, in Journal of Colloid and Interface Science, 472, 108-115.
Charge Regulation in the Electrical Double Layer: Ion Adsorption and Surface Interactions
Trefalt Gregor, Behrens Sven Holger, Borkovec Michal (2016), Charge Regulation in the Electrical Double Layer: Ion Adsorption and Surface Interactions, in Langmuir, 32(2), 380-400.
Dispersion forces acting between silica particles across water: influence of nanoscale roughness
Valmacco Valentina, Elzbieciak-Wodka Magdalena, Besnard Céline, Maroni Plinio, Trefalt Gregor, Borkovec Michal (2016), Dispersion forces acting between silica particles across water: influence of nanoscale roughness, in Nanoscale Horizons, 1(4), 325-330.
Nanometer-ranged attraction induced by multivalent ions between similar and dissimilar surfaces probed using an atomic force microscope (AFM)
Moazzami-Gudarzi Mohsen, Trefalt Gregor, Szilagyi Istvan, Maroni Plinio, Borkovec Michal (2016), Nanometer-ranged attraction induced by multivalent ions between similar and dissimilar surfaces probed using an atomic force microscope (AFM), in Physical Chemistry Chemical Physics, 18(12), 8739-8751.
Probing effects of polymer adsorption in colloidal particle suspensions by light scattering as relevant for the aquatic environment: An overview
Tiraferri Alberto, Borkovec Michal (2015), Probing effects of polymer adsorption in colloidal particle suspensions by light scattering as relevant for the aquatic environment: An overview, in Science of The Total Environment, 535, 131-140.
Forces between Negatively Charged Interfaces in the Presence of Cationic Multivalent Oligoamines Measured with the Atomic Force Microscope
Moazzami Gudarzi Mohsen, Trefalt Gregor, Szilagyi Istvan, Maroni Plinio, Borkovec Michal (2015), Forces between Negatively Charged Interfaces in the Presence of Cationic Multivalent Oligoamines Measured with the Atomic Force Microscope, in The Journal of Physical Chemistry C, 119(27), 15482-15490.
Interaction Forces and Aggregation Rates of Colloidal Latex Particles in the Presence of Monovalent Counterions
Montes Ruiz-Cabello F. Javier, Trefalt Gregor, Oncsik Tamas, Szilagyi Istvan, Maroni Plinio, Borkovec Michal (2015), Interaction Forces and Aggregation Rates of Colloidal Latex Particles in the Presence of Monovalent Counterions, in The Journal of Physical Chemistry B, 119(25), 8184-8193.
Specific Ion Effects on Particle Aggregation Induced by Monovalent Salts within the Hofmeister Series
Oncsik Tamas, Trefalt Gregor, Borkovec Michal, Szilagyi Istvan (2015), Specific Ion Effects on Particle Aggregation Induced by Monovalent Salts within the Hofmeister Series, in Langmuir, 31(13), 3799-3807.
Adsorption of polyelectrolytes to like-charged substrates induced by multivalent counterions as exemplified by poly(styrene sulfonate) and silica
Tiraferri Alberto, Maroni Plinio, Borkovec Michal (2015), Adsorption of polyelectrolytes to like-charged substrates induced by multivalent counterions as exemplified by poly(styrene sulfonate) and silica, in Physical Chemistry Chemical Physics, 17(16), 10348-10352.
Long-ranged and soft interactions between charged colloidal particles induced by multivalent coions
Montes Ruiz-Cabello F. Javier, Moazzami-Gudarzi Mohsen, Elzbieciak-Wodka Magdalena, Maroni Plinio, Labbez Christophe, Borkovec Michal, Trefalt Gregor (2015), Long-ranged and soft interactions between charged colloidal particles induced by multivalent coions, in Soft Matter, 11(8), 1562-1571.

Collaboration

Group / person Country
Types of collaboration
Klemen Bohinc, University of Ljubljana Slovenia (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Christophe Labbez, Université de Bourgogne France (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Sven H. Behrens, Georgia Institute of Technology United States of America (North America)
- in-depth/constructive exchanges on approaches, methods or results
Alberto Morpurgo, University of Geneva Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Zbigniew Adamczyk, Polish Academy of Science Poland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Ger Koper, Delft University of Technology Netherlands (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Giovanni Dietler, EPFL Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results

Associated projects

Number Title Start Funding scheme
140327 Tuning Interactions between Dissimilar Surfaces by Polyelectrolytes 01.06.2012 Project funding
111111 Transforming Pius Branzeu Center of Laporoscopic Surgery and Microsurgery (PBCLSM) Timisoara into Eastern European Zonal Center of Development and Research in Laparascopic Surgery 01.01.2006 SCOPES
136191 Designing Interactions across Interfaces in Ionic Liquids 01.01.2012 Sinergia
141849 NCCR Bio-Inspired Materials: Center for Bio-Inspired Stimuli-Responsive Materials (phase I) 01.06.2014 National Centres of Competence in Research (NCCRs)
178759 Interactions between water-solid interfaces in suspensions of charged nanoparticles 01.06.2018 Project funding
150631 Direct force measurements with combined total internal reflection and atomic force microscopy 01.12.2013 R'EQUIP

Abstract

Polyelectrolytes are widely used as additives to control properties of particle dispersions, such as their stability or rheology. In many applications, the polyelectrolytes used are oppositely charged than the substrates. In this case, strong electrostatic attraction between the polyelectrolytes and the substrates is dominant, and the adsorption mechanisms and the resulting forces between the substrates are understood reasonably well, in some situations even quantitatively. On the other hand, various successful applications rely on polyelectrolytes that have the same charge as the substrates. Interestingly, multivalent counterions, such as calcium, iron, or aluminium ions are frequently used in such formulations. The situation in such like-charged systems is hardly understood. Naively, one would expect that the strong electrostatic repulsive forces prevent adsorption completely. However, evidence exists that polyelectrolytes adsorb to like-charged substrates, and it was suggested that ion correlations may induce electrostatic attractive forces that are responsible for this phenomenon. Moreover, when the polyelectrolyte chains are repelled from the substrate, this repulsion leads to depletion interactions, which are further magnified by the structuring of the polyelectrolyte solution. In such like-charged systems, the interplay between forces described by the classical Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory, which considers electric double layer and van der Waals forces, and non-DLVO forces, such as, ion correlation, depletion, and polymer induced forces remains unclear. The systematic elucidation of the underlying interaction mechanisms is the main goal of this project. The project will investigate different well-defined model systems, and explore the role of multivalent ions along three lines. (i) Study of conformation, charge, and eventual phase separation of polyelectrolytes in solution, (ii) investigation of polyelectrolyte adsorption to like-charged substrates, and (iii) direct force measurements. These phenomena will be explored experimentally with state-of-the-art techniques, in particular, light scattering, optical reflectivity, and atomic force microscopy. These measurements will be complemented with appropriate model calculations. The project will clarify the mechanism of interactions of polyelectrolyte near like-charged substrates, and is expected to have impact in academia and industry.
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