Volume 2, Issue 6 e2000005
Full Paper

Two-Stage Polyelectrolyte Assembly Orchestrated by a Clock Reaction

Christian C M. Sproncken

Christian C M. Sproncken

Laboratory of Self-Organizing Soft Matter and Laboratory of Macro-Organic Chemistry, Department of Chemical Engineering and Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 516, 5600 MB Eindhoven (The, Netherlands

These authors contributed equally to this work.

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Dr. Berta Gumí-Audenis

Dr. Berta Gumí-Audenis

Laboratory of Self-Organizing Soft Matter and Laboratory of Macro-Organic Chemistry, Department of Chemical Engineering and Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 516, 5600 MB Eindhoven (The, Netherlands

These authors contributed equally to this work.

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Dr. Guido Panzarasa

Dr. Guido Panzarasa

Laboratory of Soft and Living Materials Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 1–5/10, Zürich, 8093 Switzerland

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Prof. Dr. Ilja K. Voets

Corresponding Author

Prof. Dr. Ilja K. Voets

Laboratory of Self-Organizing Soft Matter and Laboratory of Macro-Organic Chemistry, Department of Chemical Engineering and Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 516, 5600 MB Eindhoven (The, Netherlands

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First published: 22 April 2020
Citations: 11

Graphical Abstract

Around the clock: A cationic polyelectrolyte is assembled with temporal control by means of the formaldehyde-sulfite clock reaction. Electrostatic interactions template microscopic complexes, which are then crosslinked covalently to lock-in a preformed structure. The final particle size can be controlled simply by tuning either the concentrations of components, or the initial pH value.

Abstract

Controlling the transient self-assembly of (macro)molecular building blocks is of fundamental interest, both to understand the dynamic processes occurring in living systems and to develop new generations of functional materials. The subtle interplay between different types of physicochemical interactions, as well as the possible reaction pathways, are crucial when both thermodynamic and kinetic factors play substantial roles, as in the case of transient supramolecular assemblies. Clock reactions are a promising tool to achieve temporal control over self-assembly in non-living materials. Here, we report on the tunable association of poly(allylamine hydrochloride) (PAH) fueled by the formaldehyde-sulfite clock reaction. The electrostatic interaction between the large macromolecules and the small, oppositely charged sulfite ions gives rise to micron-sized coacervate-like complexes. As the clock proceeds, sulfite is completely depleted and the complexes dissociate. However, under suitable conditions, a subsequent reaction between the polyelectrolyte and formaldehyde can lock-in the preformed supramolecular structure, giving rise to covalently crosslinked colloidal particles.

Conflict of interest

The authors declare no conflict of interest.