An investigation of using pyrolysis bio-oil as part of the binder system for wood-based composites

The objective of this research was to investigate the feasibility of using the pyrolysis bio-oil as part of a binder system for wood-based composites. Liquid products obtained from pyrolysis process of pine wood were mixed with reactants, such as isocyanate. The adhesive binder system was blended with flakes to fabricate flakeboard. The effect of the resin content and the mix ratio of the adhesive on the physical and mechanical properties of the flakeboard were examined. Dynamic mechanical analysis (DMA) was also employed to investigate the thermal properties of the adhesives. The results indicated that a bio-oil content of 25% showed comparable properties to those produced by pure pMDI adhesive. A good correlation between the DMA results and the mechanical properties of the flakeboard was also obtained. The increase of bio-oil content in the adhesive system improved the curing speed but reduced the adhesive stiffness.