New thiosemicarbazone and Talinum triangulare vegetal extract formulations with potential anti-corrosion activity

Abstract

Corrosion is a process arising out of a chemical action of the environment on a particular material, causing its deterioration. It may occur in metals, concrete, organic polymers, and others. A promising alternative to prevent corrosion is the use of organic inhibitors. The search for new agents or formulations that enable the diminishing of corrosion effects is evidently necessary; therefore, this work evaluated 3 new formulations which contained thiosemicarbazones 4-hydroxy,3-methoxybenzaldehyde-thiosemicarbazone, 4-ethoxybenzaldehyde-thiosemicarbazone and 4-hydroxybenzaldehyde- thiosemicarbazone with the crude extract of Talinum triangulare leaves in ethyl acetate, aiming at the Fe2+ ion chelation for an anticorrosive action. UV-Vis spectroscopy was used to evaluate the formation of Fe2+ ion complexes; also, to determine the respective coordination numbers with the thiosemicarbazones. Results indicated the increase of the thiosemicarbazone anticorrosive action, which had been evaluated by molecular modeling and potentiodynamic polarization, when there were crude extract of T. triangulare leaves in the formulation.