Effect of organic additives on the interface stability of polymer coatings

A new study describes the effects of additives on the interface stability of polymer coatings in fluoric acid-based Ti and Zr treatments.
the combined properties of niobium-based and titanium-based conversion membranes were evaluated using model conversion solutions for H2ZrF6 and H2TiF6 that add a variety of organic additives (PAA, PVA, PVP). Macro-test techniques such as contact angles and stripping adhesion measurements are performed on galvanized steel plates

. Complementary to this, molecular studies of the model zinc substate were carried out using atR-FTIR of the Cretchman configuration. Macro and molecular methods show good correlations, indicating that the ATR-FTIR of the Kretschmann configuration is a valuable tool for obtaining the basic knowledge of the metal oxide-polymer interface phenomenon.
-plated steel substrate treated with polyester is more bonded to polyester coil coated primers than to polyester-treated galvanized steel substrates. The presence of organic additives does not further improve bonding properties. However, organic additives initially improved the interface stability of titanium treated substrates. However, in the long run, organic additives have been shown to be harmful to the adhesion of polyester coil coatings.
effects
in the long run, this adverse effect of organic additives can be attributed to their selective dissolution during immersion, which is most evident in titanium treatment. In the case of vanadium treatment, the role of organic additives is limited, due to the higher parts of the chemical interface bonds and the tendency of their cross-linking reactions, which cause polymer compounds to become tangled in the zirconium oxide structure.
the study was published in September 2020 in issue 146 of Organic Coatings Progress.