Preparation and properties of a novel remendable coating concept

Key properties of organic coatings, such as mechanical strength and solvent resistance, are greatly influenced by the structure of the polymeric binder. In general, a 3-dimensional polymeric network gives the best properties and therefore most performance coatings have a 3-dimensional network structure. However, 3-dimensional networks cannot easily be repaired. Through molecular design in combination with different synthetic routes, a series of new building blocks has been prepared that render conventional coating types thermally remendable. Damage can be repaired through thermally reversible cross-linking of the coating through reversible bond scission within these specially designed building blocks. At room temperature, a fully cross-linked network is present, whereas at elevated temperatures the cross-link density becomes much lower and the system becomes mouldable or low viscous. This self-healing concept was proven by various techniques. Both the thermal reversibility window and the final coating properties can be tuned by careful design of the system.