Adhesives made from isocyanates and pyrolysis oils for wood composites

Abstract Wood adhesives derived from softwood bark pyrolysis oils (PO) and isocyanates (pMDI) have been developed for particleboards with a non-conventional blending system. The PO produced by the vacuum pyrolysis Pyrocycling™ process was used to replace between 30 and 40% by weight of the pMDI in a 4% adhesive-containing particleboard. Results showed that mechanical properties (IB, MOE and MOR) and thickness swelling of homogeneous boards exceeded the minimum requirements set by ANSI A208.1-1993 and ASTM 1037-96a standards. The study showed that pyrolysis oils can be mixed at ratios as high as 40% with pMDI and give acceptable interior grade particleboard properties. It was also shown that PO reduces panel to metal adhesion by 86%, in comparison to the control.