A Coral Shell‐Inspired Biomimetic Soy Protein Adhesive Toward Electromagnetic Shielding Wood‐Based Composites

Abstract The development of multifunctional bio‐adhesives that are electrically conductive, flame‐retardant, and electromagnetic shielding is crucial for advancing next‐generation wood‐based composites. However, to date it remains a significant challenge to achieve such functionalities in adhesives while maintaining their strong adhesion. This study draws inspirations from the microstructure and properties of coral shells, and proposed a multiphase engineering to prepare a multifunctional soy protein isolate (SPI) adhesive (SPI/PA@G) by introducing a hierarchical polyaniline/phenylphosphonic acid aggregates‐loaded graphene nanoplatelets (GNPs) hybrid. Because of the presence of polyaniline/phenylphosphonic acid aggregates, the designed SPI/PA@G adhesive exhibits remarkable flame retardancy with a high limiting oxygen index value of ≈39.4%. Because the GNPs in the adhesive form a highly conductive network on wood particles surfaces, as‐prepared wood‐based composite achieves an electrical conductivity as high as 43100 S m −1 , and gives rise to an electromagnetic shielding effectiveness of 52.1 dB. In addition, multiple crosslinking interactions endow the SPI/PA@G adhesive with excellent bonding strength, as reflected by a high flexural strength of 19.7 MPa for the wood‐based composite. This study offers a new approach to the design of multifunctional adhesives and their advanced wood‐based composites, which holds great potential for real‐world applications in creating advanced functional wooden products and beyond.