Scalable Underwater Adhesives with High-Strength, Long-Term, and Harsh-Environment Adhesion Enabled by Heterocyclic Chemistry

Abstract

Developing scalable and high-performance underwater adhesives is important in various biomedical and industrial applications. However, despite massive efforts, the realization of such adhesives remains a challenging task, as mainly imposed by the difficulty in balancing the interfacial and bulk properties via an efficient way.Here, we report a facile yet effective strategy to construct a novel underwater adhesive with multiple advantaged performances by virtue of heterocyclic chemistry. This adhesive is designed with the cooperation of a heterocycle-based versatile adhesive functionality and an eco-friendly hydrophilic matrix with cross-linkable sites, which allows water absorption to destroy hydration layer, diverse molecular interactions to enhance interfacial adhesion, and abundant covalent crosslinks to strengthen bulk cohesion. Such a rational design endows the adhesive with strong underwater adhesion (up to 1.16 MPa for wood and 0.36 MPa for poly(tetrafluoroethylene) (PTFE)), long-term durability (maintaining pristine strength even after 4 months), and harsh-environment stability (salt, acidic/alkaline, low/high-temperature solutions). This strategy is also generic to derive more adhesive formulas, which offers a new direction for designing the next-generation underwater adhesives with high performance and scalability for practical applications.

Dense H-Bonding Enhanced Bio-Based Supramolecular Adhesive: High Adhesive Strength and Multi-Reusability

“…Biobased supramolecular adhesives represent an innovative approach to adhesive technology by combining renewable, natural materials with the unique properties of supramolecular interactions. − Despite advancements, the bonding strength of current biobased supramolecular adhesives remains relatively weaker compared to traditional synthetic adhesives due to the inherent weakness of noncovalent interactions. − Currently, significant research efforts are directed toward enhancing the adhesive properties of adhesives, particularly by bolstering their adhesion and cohesion strength. , Adhesion denotes the bonding strength at the interface between the adhesive and the adherend, often augmented by chemically modifying specific functional groups. On the other hand, cohesion refers to the intrinsic mechanical strength of the adhesive itself.…”