Published online by Cambridge University Press: 15 February 2011
Polypropylene (PP)-wood veneer laminates were used as a model system to investigate adhesion in wood-polypropylene composites. Wood veneers were treated with maleated polypropylene waxes (MA-PP). PP films were then compression molded to the wood surfaces and peel forces were measured.
Low MA-PP treatment levels increased the peel adhesion over that for untreated surfaces. High MA-PP treatment levels decreased the peel adhesion and intermediate MA-PP levels had no effect on the peel adhesion. Microscopy of the fracture surfaces indicated PP penetration into lumens in both treated and untreated wood veneer. Untreated surfaces also exhibited PP penetration into pits and intercellular spaces, while treated surfaces exhibited only hindered penetration on this scale. The penetrated PP formed tendrils during fracture. DSC of PP on wood and cellulose surfaces showed higher PP crystallization temperatures on untreated surfaces than on treated surfaces.