THE EFFECT OF LOWERING THE SURFACE FREE-ENERGY OF WATER ON THE THERMODYNAMIC WORK OF ADHESION

The dispersive and polar force components of surface free energy have been measured for water left in contact with films dried from various emulsion adhesives. The polar component was lowered but the dispersive components were about 28 mJ m-2 in each case. From these measurements of thermodynamic work of adhesion in the presence of contaminated wat er have been calculated for adhesive-polystyrene interfaces. An equati on has been derived giving the dependence of thermodynamic work of adh esion upon the total surface free energy of water. It shows that the t hermodynamic work of adhesion decreases as the surface free energy of water is lowered, but it eventually reaches a minimum and then may inc rease slightly.