Multifunctional polyurethane coatings with excellent antifouling and self-healing properties

Polydimethylsiloxane (PDMS) has been widely used to improve the antifouling properties of polyurethane (PU) coatings due to its low surface energy. Herein, a novel type of waterborne polyurethane (WPU) coating with good antifouling and self-healing abilities was synthesized by incorporating PDMS and disulfide bonds. The effects of PDMS and the disulfide content on the thermal, mechanical and surface properties of the coatings were investigated. Benefiting from a rational structural design, the obtained WPU coating manifested superior antifouling properties. In addition, the WPU coating exhibited good healing capabilities owing to the collaboration between dynamic disulfide bonds. Interestingly, the self-healing of an experimental crack occurred at a temperature above 60°C, and the coating recovered its mechanical properties to 95%. This finding has great significance for the design of multifunctional smart coatings for diverse applications.