Stimuli-responsive polyurethane-urea polymer for protective coatings and dampening material

Intrinsic self-healing coatings have been drawing more and more attention over recent years. A self-healing coating that is able to maintain its original appearance and performance after damage is attractive for a huge scope of applications. This article reports the synthesis of a polyurethane-urea coating with 1-(2-aminoethyl)-imidazolidin-2-one (UDETA) units showing temperature- and moisture-triggered self-healing. Calorimetric and spectroscopic analyses give insight into the self-healing mechanism showing that the absorbed water is able to disturb inter- and intramolecular hydrogen bonds of the polymer chains and decrease the glass transition temperature of the polymer. Temperature-mediated self-healing can be performed from 80 up to 200°C. Aside from self-healing, the molecular dynamics in the polyurethane-urea polymer prove to be beneficial for damping applications as confirmed by dynamic mechanical analysis. Thus, the polymer system features properties that are useful for two different applications, namely in coatings with self-healing and corrosion protective properties and in dampening materials.