HYDROCARBON-SOLUBLE ALKYLANILINE FORMALDEHYDE OLIGOMERS AS CORROSION-INHIBITORS

Hydrocarbon-soluble oligomers were prepared by the acid-catalyzed condensation of alkylanilines with formaldehyde. Highest molecular weight oligomers (MW approximately 6000) were obtained from alkylanilines prepared by the Friedel-Crafts alkylation of aniline with alpha-olefins. By NMR, it was shown that the oligomers contain structures corresponding to methylene-linked aromatic rings and methylene linked to both an aromatic ring and a nitrogen atom. The oligomers exhibit very good initial inhibition of metal corrosion in aqueous environment; and the inhibition is more persistent than that observed with monomeric analogs.