IB of the 8%-UF bonded spruce particleboard was similar to the sunflower one, but lower than the topinambour and cup-plant 4% MDI-produced particleboards. Likewise, the IB of the 12% UF-spruce particleboards turned out to be similar to the particleboards made from sunflower, topinambour as well as cup-plant particleboards, the latter all bonded with 6% MDI. All panels met P1 class of EN 312.
The drawback of the reduced IB of the alternative material particleboards could be partly compensated by different approaches.
One option would be to use finer particles (Arabi et al., 2011), which further improves IB. Particleboards of a higher density (Wong, 1999), or lower boardıs ´ thicknesses (Hunt et al., 2008) have also delivered higher IB values.