One-Step Synthesis and Performance Evaluation of a Sucrose–Glyoxylic Acid Wood Adhesive

Environmental and health concerns drive research into sustainable bio-based wood adhesives. This study utilized widely available and economical sucrose and glyoxylic acid as raw materials to prepare a wood adhesive via a one-step method. The effects of glyoxylic acid content on the adhesive structure, properties, and plywood application performance were statistically investigated. The results demonstrated successful esterification and acetalizations between glyoxylic acid and sucrose, forming a dense three-dimensional cross-linked network that enhanced bonding performance, water resistance, and thermal stability. At 40% glyoxylic acid content, the adhesive exhibited optimal comprehensive properties: the wet shear strengths of 1.39 MPa (63 °C) and 1.17 MPa (93 °C) that substantially exceeded GB/T 17657-2022 requirements. This study provides novel insights and a practical foundation for high-value sucrose utilization and green wood adhesive development.