Heat-Free Emulsion Adhesive Exhibiting Excellent Bonding Strength and Water Resistance

Wood adhesives are extensively utilized in furniture manufacturing and repair as well as in the construction industry. Developing adhesives that possess rapid bonding capabilities, exceptional adhesive strength, and the ability to cure without heating is a significant area of research. During application, plywood often experiences adhesive failure due to the stress concentration. Inspired by the structure of spider webs, this study developed a carboxylated styrene–butadiene latex-based wood adhesive capable of effectively dissipating stress while exhibiting superior adhesive strength. The strategy involves grafting trifluoroethyl acrylate and glycidyl methacrylate onto the carboxylated styrene–butadiene latex backbone, employing tetraethylenepentamine as a cross-linking agent to construct a multilevel cross-linked structure via ring-opening and amidation reactions. Motivated by the spider web structure, the adhesive forms a multilevel cross-linked network through covalent interactions such as amine ether and amide bonds between the main chains, enhancing the system’s cohesion. Additionally, noncovalent interactions such as hydrogen bonds and π–π stacking improve interfacial adhesion and stress dissipation. These multiple interactions significantly enhance the adhesive strength. The adhesive can achieve rapid bonding within 3 min at room temperature, with a dry bonding strength of 3.29 MPa and a wet bonding strength of 1.91 MPa. The bonding process does not require additional heat sources, effectively reducing the energy consumption. Compared with traditional heat-curing adhesives, this adhesive offers low energy consumption, ease of operation, and environmental friendliness, making it highly suitable for applications in furniture maintenance and other scenarios where heat curing is impractical.