Superior strength, highly stretchable, bionic self-healing polyurethane and its composites for flexible conductivity and self-cleaning applications.

Balancing the exceptional mechanical strength and repair efficiency of self-healing materials presents a significant challenge to unlocking their full potential in practical applications. Inspired by natural spider silk and cartilage, multiple dynamic hydrogen bonds were introduced into the pre-prepared polyurethane (PU). Then modifided graphene oxide (GO) nanosheets with dynamic hydrogen bonds were added into the prepared PU to form composites (AU-PU/GDU) to establish a dense hydrogen bond network structure, providing strong interfacial interactions. The AU-PU/GDU film exhibits excellent tensile strength (39.6 MPa), high elongation at break (1155.6 %), and outstanding repair efficiency (90.3 %). Using AU-PU/GDU as the flexible base, a superhydrophobic conductive composite coating (F-AU-PU/GDU) with a contact angle greater than 150° was prepared by incorporating superhydrophobic nanomaterials. This work lays the foundation for the development of multifunctional materials through the creation of self-healing superhydrophobic conductive composite coatings, which have a wide range of potential applications. Functionalized graphene oxide forms a coating on a flexible, self-repairing polyurethane film, resulting in the composite film with super-strong strength, toughness, high extensibility, conductivity, and superhydrophobicity. After damage, the composite film undergoes repair with minimal impact on its electrical conductivity and superhydrophobic properties. [Display omitted] • Self-healing polyurethane composites with a hierarchical hydrogen bonding structure was successfully prepared. • The surface of polyurethane coated with modified nanoparticles showing superhydrophobicity and electrical conductivity. • The composite film has excellent tensile strength, high stretchability. [ABSTRACT FROM AUTHOR]