High-Performance Adhesive Joint Made from Densified Wood

The strength of an adhesive joint plays a major role in the implementation of engineering wood products; therefore, joint performance receives intense scrutiny. This study investigated a wooden adhesive joint, made from densified wood, the performance of which was dramatically enhanced. The wood sample was developed by performing mechanical compression and polymer impregnation on rubberwood. This treated rubberwood was additionally prepared by simple surface sanding prior to jointing. The highest wettability was found on surfaces sanded with the largest grit sandpaper. Consequently, glueline thickness increased with progressively larger grit (smaller grit number) sandpaper. In addition, the maximum shear strength for the joint made from the densified rubberwood was greater than that of that made from the original one, by 40%. Surprisingly, with the optimal sanding treatment, the shear strength of the wooden joint gradually increased with an increase in the density of the densified rubberwood from 1.05 to 1.30 g/cm³. Moreover, the rate of wood failure also increased throughout the stated density range.