Adhesion Properties of Polyelectrolyte-Chemisorbed Zinc Phosphate Conversion Coatings,

摘要

The outermost surface sites of polyelectrolyte complexed crystalline zinc phosphate (Zn-Ph) layers precipitated on cold rolled steel surfaces act significantly to promote interfacial adhesive bonding to polymeric topcoats. This is the result of electrostatic internal diffusion and segmental chemisorption mechanisms of polyelectrolyte macromolecules either on newly precipitated crystal nuclei or on crystal growth sites during the primary Zn-Ph conversion process. The nature of the polymer-to-polymer chemical bond produced at the polymer-to-polymer complex Zn-Ph adherend interfacial joints plays the key role in the achievement of long-term bond durability upon exposure to chemically corrosive environments. Reprints. (mjm)