Protective sol–gel films modified with tannin extracts
In a present work, tannins extracted from tamarind shells using water and ethyl acetate were introduced into fabricated sol–gel containing 3-glycidoxypropyltrimethoxysilane (GPTMS) and tetraethoxysilane (TEOS) which were subsequently assembled over mild steel surface.
The result of electrochemical studies revealed that the maximum inhibition efficiency achieved at 1000 ppm was up to 90%. With regards to FTIR spectra, the infrared bands at −1046 and −935 cm−1 confirmed the formation of (Si–O–Si) and (Fe–O–Si) covalent bonds.
Enhanced protection ability
The presence of this peak indicates the formation of networks between the mild steel substrate and silicate. According to the researchers, their study has revealed that tannins doped GPTMS-TEOS silanol matrix enhanced the protection ability by promoting crosslinking reactions of the coatings compared to undoped coatings to a significant extent.
The study has been published in Journal of Sol-Gel Science and Technology, Volume 104, October 2022.
