Synthesis, characterization and application of glucosyloxyethyl acrylate graft chitosan against pipeline steel corrosion
By Eduok, Ubong; Ohaeri, Enyinnaya; Szpunar, Jerzy; Akpan, Inemesit
Published in Journal of Molecular Liquids
Journal of Molecular Liquids
2020
Abstract
In this study, glucosyloxyethyl acrylate graft chitosan (GA-CHS) was synthesized by reacting chitosan with glucosyloxyethyl acrylate, previously prepared via catalyzed ?-d-glucopyranoside transesterification with excess 2-hydroxyethyl acrylate. This graft GA-CHS copolymer was utilized as a corrosion inhibitor for API 5 L X70 pipeline steel in chloride-enriched (1 M HCl) acid solution. GA-CHS adsorption on the steel surface led to significant inhibition of chloride-induced corrosion compare to unmodified chitosan (CHS). In the presence of GA-CHS, corrosion inhibition increased with its concentration due to the formation of compact protective films; compositional and morphological evidences have been provided. Without this graft copolymer in corrosive electrolytes, the steel coupons corroded due to unrestricted chloride-induced attacks, leading to severe surfaces pits. The linear GA-CHS polysaccharide moiety could have been a contributing factor and the greater edge over unmodified chitosan, regarding enhanced corrosion inhibition as well as its hydroxyl/amino chemical groups in combination with its acrylate functionality.