Nacre-inspired High-Performance Multifunctional Plant Protein Adhesive Through Vitrimer Networks

Natural materials show a special combination of remarkable strength and toughness. Therefore, inspired by nacre's "brick-and-mortar" architecture, high-performance multifunctional plant protein adhesives were constructed through an organic-inorganic hybrid structure and vitrimer networks. Hydroxyl-functionalized boron nitride (BN-OH) nanosheets firstly acted as the "brick" part, and protein chains were thought of as the "mortar" part. BN-OH can not only enhance the toughening through interlayer interface slip, but also achieves synergistic toughening effect with the nanometer effect. Glutaric dialdehyde (GD) acted as a "bridge" between protein chains and BN-OH, which can react with the condensation of hydroxyls in BN-OH or with active amino groups in protein chains to form dynamic covalent bond (vitrimer networks) to dissipate energy. Therefore, the synthesized multiple crosslinked network plant protein adhesives have excellent wet shear strength (1.28 MPa), water resistance, mildew-resistant, flame-retardant, and ultrahigh thermal management capability (3.88 W m-1 K-1), and has wide application potential in green adhesives.