Dry adhesion study of polyester/melamine clear coats on galvanized steel

摘要: Abstract The dry adhesion strength of polyester/melamine clear coats varying in their branching degrees were applied on galvanized steel panels and investigated by pull-off T-bend testing. It was found that tensile is mainly dominated the type coating less influenced pretreatment substrate. In contrast, critical strain affected surface treatment layer with higher stiffness but lower ductility compared to coat. Pull-off at room temperature correlating glass transition Tg a strong viscoelastic contribution ascribed work adhesion. Samples adhesive as well cohesive failure modes further X-ray photoelectron spectroscopy (XPS) determine interfacial chemistry. Angle-resolved XPS data suggest nitrogen from melamine crosslinker plays decisive role for coatings. Regarding distribution micro- nanostructural effect has be considered: while maximum concentrations over depth are usually bulk region these coats, this proposes remaining interface segregates towards metallic