From polyelectrolyte complex films to smart functional coatings

Recently, coating research has shifted from organic solvent-based coatings to water-based coatings due to the toxicity and environmental effects of volatile organic compounds (VOCs). This brings challenges, since the conventional base materials for coatings are often insoluble in water. Therefore, water-soluble polyelectrolytes have been the object of study as a novel coating binder material. In previous research, polyelectrolyte complexation triggered by evaporation of a volatile base was shown to effectively induce coating formation. However, to truly render polyelectrolyte complex coatings smart and of higher commercial interest, functionality should be added to the coatings. Here, we aim to instil functionality by addition of a variety of responsive molecules, macromolecules and particles. Through these additives as well as changing the polyelectrolyte building blocks, functionalities such as flame retardance, antibacterial activity, antifouling activity and structural colour will be added. These advanced functionalities will push polyelectrolyte complex coatings from theory towards practical application. This project is in collaboration between Wageningen University (prof. Jasper van der Gucht) and University of Twente (prof. Wiebe de Vos), with industrial supervision from AkzoNobel and BASF. These participants are connected within the Advanced Research Centre - Chemical Building Blocks Consortium (ARC-CBBC).