Poplar Wood Modification Using Hyperbranched Epoxy Resin/2D Resin

To address the limitations of poplar wood, including insufficient toughness and flammability, this study used hyperbranched epoxy resin (HBEP) and low-formaldehyde dimethylol dihydroxyethylene (2D) urea resin to construct a composite impregnation (HBEP/2D) system. Through the full-cell process, the HBEP/2D composite impregnation solution underwent in situ curing and cross-linking within the wood structure, thereby enhancing its physicomechanical properties. Using ultrasonic blending, a homogeneous and stable HBEP/2D composite impregnation solution was developed. Impact toughness was used as the evaluation criterion to investigate the optimal impregnation process. The effect of the modification process on the physical and mechanical properties of the modified sample was analyzed. Under the optimum impregnation process, thermogravimetric analyzer (TG) analysis indicated that the temperature corresponding to the maximum pyrolysis rate increased from 336.4 to 349.9 °C, and the char yield increased from 14.82 to 23.83%. Modulus of rupture (MOR), modulus of elasticity (MOE), and impact toughness of the modified sample (145.46 MPa, 19.10 GPa, and 69.35 kJ/m 2 ) were increased by 69.14, 78.34, and 38.70%, respectively, compared to the control sample. This study prepared modified samples with improved dimensional stability and mechanical strength, indicating the potential of wood materials for use in residential decoration and engineering applications.