Tough, Instant, and Repeatable Adhesion of Self-Healable Elastomers to Diverse Soft and Hard Surfaces

Repeatability and high adhesion toughness are usually contradictory for common polymer adhesives. Repeatability requires temporary interactions between the adhesive and the substrate, while high adhesion toughness is usually achieved by permanent bonding. Integrating these two features into one adhesive system is still a daunting challenge. Here, the development of a series of viscoelastic elastomers composed of a soft and hard segment is reported, which exhibit tough, instant, yet repeatable adhesion to a variety of soft and hard surfaces. Such a combination of mutually exclusive properties is attributed to the synergy of high mobility of polymer chains and massive viscoelastic dissipation of the elastomers around the interface. By optimizing the relaxation time and mechanical dissipation, the resulting adhesives can achieve a tough yet repeatable adhesion toughness above 2000 J m(-2), superior to the best-in-class commercial adhesives. Numerous acrylate monomers are proven applicable to the preparation of such adhesives, validating the universality of the fabrication method. The application of these elastomers as adhesive and protective layers in soft electronics by virtue of their universal and tough adhesion to various soft and hard substrates is also demonstrated.

Automated summary

This study reports the development of viscoelastic elastomers composed of soft and hard segments that exhibit tough, instant, yet repeatable adhesion to various soft and hard surfaces. The combination of mutually exclusive properties is achieved through the high mobility of polymer chains and massive viscoelastic dissipation of the elastomers. By optimizing relaxation time and mechanical dissipation, the resulting adhesives achieve a tough yet repeatable adhesion toughness exceeding 2000 J m(-2), surpassing commercial adhesives. Additionally, the applicability of numerous acrylate monomers for the preparation of such adhesives is validated, and their use as adhesive and protective layers in soft electronics is demonstrated.