Encapsulation of 8-HQ as a corrosion inhibitor in PF and UF shells for enhanced anticorrosive properties of renewable source based smart PU coatings

Abstract

Encapsulation of 8-HQ into PF and UF microcapsules was carried out to enhance the anticorrosive properties of renewable source based PU coatings. Microcapsules were characterized using optical microscopy and FE-SEM for their morphological behavior as well as using a particle size analyzer to determine the mean diameter of the microcapsules. A release study of the inhibitor used to form both shell materials was estimated using UV visible spectroscopy. A thermal study of the microcapsules and polyurethane (PU) smart coatings formulated with the microcapsules was conducted using TGA. The prepared smart coatings were checked for their physico-mechanical and anticorrosive properties, which were tested against 0.5 M HCl solution via an immersion method and a gravimetric method. PU coatings loaded with PF and UF microcapsules displayed the best anticorrosive performance. On comparing the shells, PU coatings loaded with encapsulated 8-HQ into PF showed better results than the coatings loaded with UF based microcapsules.