Controlled oxidation of dextran for evolution of polyether segment bearing pendant carboxyl groups for corrosion inhibition applications

Partially oxidized dextran containing carboxyl groups was prepared as an environmentally benign organic corrosion inhibitor for mild steel. Introduction of carboxyl groups was accomplished by oxidation of dextran using sodium hypochlorite under basic conditions. The structure of the product was confirmed by spectroscopic measurements. GPC analysis revealed that oxidation of dextran proceeded without significant molecular-weight degradation. ¹H NMR spectra revealed that up to 1.3 carboxyl groups per repeating unit were introduced into the polymer. The product showed moderate corrosion inhibition activity for mild steel, and biodegradability under conditions for cooling water systems.