Effects of adhesives on the physical and mechanical properties of chip block pallets from mixed forest group wood biomass

The rapid development of the manufacturing industry has increased the demand for sustainable and efficient logistics solutions. Chip block pallets (CBPs) made from mixed forest group sawdust offer a promising alternative to traditional pallets due to their reliance on lower-cost, renewable materials. This study aims to evaluate the effects of different adhesives, phenol-formaldehyde (PF), urea-formaldehyde (UF), and poly-urea-formaldehyde (PUF), and varying pressing times on the physical and mechanical properties of CBPs. The CBPs were produced using 30, 60, and 90 min pressing times at 180 °C. The results showed that PF demonstrated the highest compressive strength (6.93 MPa) and screw-holding strength (343 N), making it suitable for applications requiring high mechanical performance. The PUF exhibited lower mechanical strength but provided significant environmental advantages with reduced formaldehyde emissions. Meanwhile, UF displayed adequate performance at shorter pressing durations but decreased efficiency with prolonged pressing. Optimal results were achieved at a pressing time of 60 min, which improved physical and mechanical properties while minimizing water absorption. These findings highlight the potential of CBPs as an eco-friendly and effective alternative, with adhesive and pressing parameters tailored to meet specific application requirements.