Mechanical Properties and Biological Performance of Particle Board Made of Sendan (Melia azedarach)

Sendan (Melia azedarach), a domestic fast-growing species in Japan, was used as a material of particle board (PB). Sendan lumber was crushed into chips using a hammer mill, and PB was made of these chips with p-MDI adhesive. For a reference, recycled chips including softwood were also used for a fabrication of PB. The mechanical properties of PB and the biological performance of solid wood and PB were investigated. Bending strength, internal bonding strength, and thickness swelling were evaluated for mechanical properties of PB, meeting the Japanese industrial standard (JAS). For the biological performance tests, solid woods of sendan and sugi were used. Termite resistance and decay resistance of both the solid woods and the PBs were evaluated. The mechanical properties of sendan and recycled PBs met the criteria of JAS. A white-rot jungus, Trametes versicolor decayed sendan heartwood and sendan PB more easily than sugi heartwood and recycled (softwood) PB, respectively. The termite resistance of sendan heartwood and sendan PB was superior to that of sugi heartwood and recycled PB, respectively. The higher density and the solvent removal of extractives in sendan heartwood were likely to be responsible for their high termite resistance.