Bioinspired Sclerite-coupled embedded network for mechanically robust interfacial adhesion

Developing adhesives that exhibit high strength and toughness continues to present a challenge in materials science. Conventional water-based adhesives often face a trade-off between rigidity and flexibility, limiting their practical performance. Inspired by the hierarchical structure of soft corals, this study aims to design a biomimetic adhesive that achieves an optimal balance between strength, toughness, and water resistance. A sclerite-coupled embedded network architecture (SCENA) was developed, integrating multiple reinforcing components within a single system. A water-soluble isobutylene-maleic acid copolymer (IBMAA) served as a long-chain polymer backbone to provide structural support and chemical reactivity. Amino-terminated hyperbranched siloxane was incorporated to create a three-dimensional chemically cross-linked network, enhancing cohesive strength and flexibility. Rigid nano-silica particles acted as biomimetic "sclerites", forming confined reinforcement domains that further strengthened the architecture. The resulting SCENA adhesive exhibited exceptional performance, achieving dry and wet shear strengths of 2.61 and 1.55 MPa, respectively, surpassing most reported water-based adhesive systems. The debonding energy reached 1536 N/m-representing a 289% improvement over the IBMAA baseline-demonstrating significant toughness and energy dissipation capacity. The proposed biomimetic SCENA design overcomes the traditional trade-off between strength and toughness in water-based adhesives. This biomimetic nanostructured design provides a new pathway for eco-friendly, high-strength adhesive systems, offering broad potential for wood-based composites, structural construction materials, and lightweight automotive assemblies.