Preparation of the water-resistant eco-friendly carbohydrate wood adhesives by Schiff base reaction.

To prepare biomass-based wood adhesives with good bonding properties and water resistance is still a challenge and meaningful work in the field of the wood industry. Thus in this present study, under low reaction temperature conditions (50°C), sodium periodate was used as an oxidant to treat carbohydrates such as glucose, sucrose and starch to form biomass-derived aldehydes solutions. Then oxidized glucose- hexamethylenediamine (OGLH), oxidized sucrose- hexamethylenediamine (OSUH) and oxidized strarch-hexamethylenediamine (OSTH) resins were prepared via Schiff base reaction from these solutions with hexamethylenediamine. The resins obtained were applied to the preparation of three-layer laboratory plywood. The whole synthesis was a simple process and low energy consumption; meanwhile, OGLH and OSUH resins show excellent bonding performance, allowing them to be able to consider as a substitute for the current widely used urea-formaldehyde (UF) and its modified resin wood adhesives. Furthermore, this study provides a new process reference for the preparation of carbohydrate-based adhesives. [ABSTRACT FROM AUTHOR]