Project
From polyelectrolyte complex films to smart functional coatings
Polyelectrolyte coatings can be used as sustainable alternatives to conventional coatings. Polyelectrolytes are molecules (often, polymers) with multiple charges. Polyelectrolyte complexes form when two oppositely charged polyelectrolytes start interacting electrostatically, with the opposite charges forming effective ‘crosslinks’ within the material. These crosslinks result in the formation of a strong network, which makes these complexes solid and tough.
In this project, we use the dependence of charge on the pH of the solution, to start complexation only when the coating is applied. The coating mixture is made in water, which makes then inherently more sustainable than solvent-based coatings. To change the pH after application, we add a small amount of ammonia, which evaporates during drying, causing the pH to drop and complexation to occur. The current overarching goal is to understand the fundamentals of the phase transitions during complexation, and to add more functionalities to the coatings.