A Mussel-Inspired Design for Robust Catechol-Functionalized Cross-Linking Adhesives Uniting Water Resistance,
Wei Wang1, Jie Liu1, Shilong Zhu1
1State Key Laboratory of Fine Chemicals, Department of Polymer Science and Engineering, Liaoning Key Laboratory of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
Abstract:
In the pursuit of green and sustainable development, there is an urgent demand for environmentally friendly adhesives that maintain a stable adhesion under harsh conditions. In this work, bioinspired by the synergistic mechanisms of mussel proteins, we designed a readily accessible and environmentally friendly catechol-functionalized cross-linking adhesive (MPCs) via molecular engineering and thiol-ene click chemistry. By optimizing solvent selection, we preserved a higher density of phenolic hydroxyl groups, significantly enhancing the interfacial adhesion. The resulting adhesive reaches remarkable lap shear strengths of 2.13 MPa in 63 °C water and 1.75 MPa in liquid nitrogen (-196 °C), surpassing most reported catechol-based adhesives. Notably, MPCs exhibit excellent recyclability through thermal reprocessing, retaining strong adhesion even after 10 reuse cycles. Mechanical testing reveals a tensile strength of up to 48 MPa, while the inherent π-π interactions between benzene rings confer photoluminescence under UV irradiation. This property enables fluorescence-based damage detection, as localized mechanical damage causes measurable intensity shifts. Furthermore, MPCs could degrade controllably through ester-linkage hydrolysis in the cross-linker, generating products with excellent biocompatibility. This work not only advances the design of bioinspired adhesives but also provides a sustainable solution for marine-environment and extreme-environment applications.
