Synthesis of a Dipyridyl Disulfide Cross-linking Reagent and Its Application to Photo-adhesion of Dissimilar Materials

Abstract

Photo-adhesion of dissimilar materials was performed by using a diacrylate cross-linking reagent containing a 2,2'-dipyridyl disulfide moiety. Cross-linking reagent designed in this work was purified by recrystallization. UV-cured films were fabricated with the cross-linking reagent, 4-hydroxybutyl acrylate and a radical photo-initiator. Hydrophilicity of the film surface seemed to be changed larger than that of control samples. In photo-adhesion experiments, 0.3-2.5 MPa of shear stress was recorded after 1 J/cm2 of UV irradiation at a wavelength of 365 nm. Remarkable improvement of adhesive strength was observed when copper adherends were used, suggesting interaction between copper surface and sulfur atoms of the dipyridyl disulfide moieties in the adhesive layer.