THE ADHESION OF POLYSTYRENE TO WOOD

This article gives a review of certain concepts of adhesion and reports some experimental results. The main conclusions are as follows: The adhesion of polystyrene to wood is in about 60% the effect of dispersion forces and in the rest of polar forces. The non compensated polar forces of the wood substrate causes a surface tension on the wood-polystyrene interface. The weakest link in the wood-polystyrene system is the polystyrene and not the wood-polystyrene interface. A great influence on the "practical" adhesion measured by a pull-off test has the contraction of polystyrene during the thermocatalytic polymerization and involved shrinkage stresses which cause cavitation in polystyrene.