Simultaneously strengthening and toughening reprocessable basswood through reactive waterborne acrylic resin impregnation

It is indeed challenging to simultaneously strengthen and toughen woody material while maintaining its recyclability using existing modification technology. In this study, we have successfully fabricated high-performance and re-processable basswood with outstanding dimensional stability through reactive waterborne acrylic resin impregnation. The pathways of resin movement within the basswood’s multi-scale structure were discussed in detail. In comparison with unmodified wood, the compressive strength parallel/perpendicular to the grain, hardness, and modulus of rupture (MOR) were increased by 73.8 %, 179.4 %, 406.1 %, and 113.6 %, respectively. The compressive strength reached the standard of C70 degree for concrete, and MOR complied with the highest standard (TB20) of hardwood used as a building material. Moreover, the impact bending strength was enhanced by 113.1 % compared with the unmodified wood. Additionally, the water uptake of modified wood was 85.4 % lower than the unmodified wood, and the anti-swelling effect reached up to 42.8 %. Furthermore, the modified wood demonstrated recyclability and retained satisfactory strength after reprocessing, with the tensile strength of the first recovery reaching 22.5 MPa and the flexural strength reaching 31.5 MPa. This study thus provided a novel strategy for creating high-performance and recyclable wood, which holds significant promise for expanding the application area of woody materials, especially as a replacement for non-renewable materials such as concrete in the construction field.