Effect of surface polarity on self-adhesion of polymers

Abstract The work of detachment, W , of two attached polymers has been determined experimentally for systems consisting of unoxidized and chemically oxidized low density polyethylene (PE) film. The surface density of polar, mainly carbonyl, sites at the surfaces of oxidized polyethylene has been measured by adsorption of calcium ions. Independent measurements of the wettability of these surfaces by pure liquids allows the establishment of a relation between the thermodynamic free energy of adhesion, W A , the polar contribution, γ p s , of the polymer to this energy and the surface density of polar sites. An attempt to correlate these parameters with the adhesion energy, W , has been made. The importance of the surface polarity on the possible mechanism of polymer self-adhesion is discussed.