Radiation grafted adhesive primers

Electron-beam and UV radiation can induce covalent attachment of unsaturated monomers onto a variety of polymer surfaces. The surface characteristics of a polymeric material can therefore be precisely manipulated by grafting the proper combination of monomers onto the surface. Radiation-grafted, sterically nonhindered tertiary acrylamides behave surprisingly well as primers for acidic pressure-sensitive adhesives. Physical and spectroscopic analyses of grafted acrylamides indicate that this unusual behavior is due to hydrogen bonding between the amide functionality in the primer and the acid functionality in the adhesive. Primary and secondary acrylamides are postulated to be less effective because they have the tendency to form hydrogen bonded dimers within the primer rather than interacting with the adhesive.