A novel and facile method for constructing micro-nano porous phytic acid pretreatment layer on metal surface

A novel and environmental-friendly pretreatment layer was prepared on a mild steel from an aqueous solution of polyvinyl alcohol (PVA)-grafted phytic acid (PA). This composite pretreatment layer provides greatly improved adhesion to the metal substrate, owing to the strong chelation and coordination interaction between PA and metals. Meanwhile, PVA modification produces highly porous structure in the hybrid layer. This is beneficial to the improvement of adhesion between metal substrates and subsequent polymer coatings. Further, the highly porous structure is good at loading -corrosion inhibitors, and the polymeric coatings painted on PVA-PA pretreatment layer pre-encapsulated with inhibitors exhibit satisfactory anticorrosion performance.

Automated summary

The novel PVA-PA composite pretreatment layer significantly improves adhesion to the metal substrate through strong chelation and coordination interaction, as well as enhancing adhesion through the highly porous structure provided by PVA modification. The highly porous structure also allows for loading of corrosion inhibitors, resulting in satisfactory anticorrosion performance in polymeric coatings painted on the pre-encapsulated with inhibitors.