Adhesive

Engineering

Polymer chemistry

Materials science

Boron nitride

Graphene

Layer (electronics)

Chitosan

SILK

Chemical engineering

Soil water

Nanotechnology

Hexagonal boron nitride

Environmental science

Soil science

Composite material

Spider silk

Shear strength (soil)

Exfoliation joint

Chemical Engineering Journal

A facile and environment-friendly bionic strategy is developed to construct high-performance soybean meal (SM)-based multifunctional adhesives by using chitosan-functionalized boron nitride nanosheets ([email protected]) as an alternative to β-sheet nanocrystals to mimic the structural characteristics of natural spider silks. [email protected] were cost-effectively and greenly produced from bulk hexagonal boron nitride through chitosan-assisted mechanochemical exfoliation. Compared with the neat crosslinker-modified SM-based adhesive (MSM), the fabricated adhesive (MSM/[email protected]) features remarkable improvement in mechanical performance, such as enhanced wet shear strength (1.31 MPa vs. 0.58 MPa), work of debonding (0.366 J vs. 0.186 J), and dry shear strength (1.96 MPa vs. 1.42 MPa). The outstanding performance is attributable to the dense covalent/non-covalent intermolecular interactions and good compatibility between [email protected] and the SM matrix, which are beneficial to the dissipation and transfer of energy under loading. In addition, the MSM/[email protected] adhesive exhibits noticeably improved flame retardancy and excellent anti-mildew performance compared with the neat SM-based adhesives, and its shelf life reaches up to 72 h. Such an advanced MSM/[email protected] adhesive reaches the engineering resin level and possesses promising potentials for industrial applications. Overall, this facile and efficient spider silk-mimicking structural design strategy assisted by a green and low-cost mechanochemical exfoliation would provide endless inspirations for constructing and reinforcing multifunctional bio-based adhesives, elastomers, and plastic materials.

Spider silk-inspired high-performance soybean meal-based adhesive reinforced by greenly produced chitosan-functionalized boron nitride nanosheets