Achieving simultaneous exceptional adhesion and recyclability remains a formidable challenge due to the inherent strength-toughness trade-off and stability-switchability conflict in adhesive systems. Inspired by the hierarchical architecture of cartilage, we report a bioinspired cross-linked network integrating B-N coordination bonds and dynamic boronic ester linkages for high-performance recyclable adhesives. The biomimetic design replicates the structural organization of cartilage's collagen-proteoglycan matrix, where dynamic B-N coordination bonds between network junctions facilitate energy dissipation through bond dissociation-induced network elongation. The network is constructed via 3-amino-1,2-propanediol-mediated epoxy ring-opening and subsequent cross-linking with 1,4-phenylenediboronic acid, forming a dynamic covalent polymer network, denoted as BEAD (boronic ester adhesive), with high cross-linking density. BEAD exhibits exceptional mechanical properties (46.42 ± 5.32 MPa tensile strength, 2.60 ± 0.31 MJ/m³ toughness) and robust adhesion (26.69 ± 0.74 MPa lap shear strength on steel). The synergy of B-N coordination (enhancing cohesion) and boronic ester exchange (enabling reprocessability) yields an optimal balance of strength and recyclability, retaining 80.7% adhesion performance after five reprocessing cycles. The study presents a biomimetic dynamic bonding strategy to overcome the strength-recyclability trade-off in adhesives, establishing a sustainable paradigm for structural materials.
Bo Qian,Yuepeng Wang,Zekai Wu,Yujie Jia,Ming Liu,Jilin Su,Yihan Wang,Zhechen Zhao,Jiani Wu,Wei Sun,Ming Tian,Zhengwei You
High adhesive strength and reversible rapid bonding are a long-lasting trade-off in polyurethane adhesives; integrating these advantages remains a key challenge for developing next-generation polyurethane adhesives. Additionally, performance limitations in complex environments and the inability to monitor structural changes in the curing process persist as unresolved issues. Here, a dual-dynamic crosslinking polyurethane adhesive that combines thermally responsive oxime-carbamate bonds and Diels-Alder reactions are presented to achieve both strong reversible adhesion and environmental tolerance. The synergistic effect of dual dynamic bonds yields remarkable adhesive strength under ambient (11.51 MPa) and ultra-low temperature (−196 °C, 9.57 MPa) conditions, with adhesive strength 1.46-fold enhanced in the aqueous environment over 45 days. Through real-time monitoring of electrical property evolution during the curing process, the structural transformations responsible for the adhesive's enhanced performance characteristics are elucidated. This work establishes a robust framework for designing high-performance reversible polyurethane adhesives.
危险品化学品经营许可证（带存储）