The electrochemical behavior of zinc metal in a strong alkaline (8.5 M KOH) solution in the presence of HCO2 - CH2 - (OCH2CH2) - CH2 - CO2H, dicarboxylic acid modified poly(ethylene glycol) (PEG) was studied. Electrochemical methods (linear polarizations and potentiodynamic and potentiostatic techniques), spectroscopic (Fourier transform IR), morphological (scanning electron microscopy), and imaging studies (atomic force microscopy) revealed that the ability to inhibit zinc corrosion in the strong alkaline solution with low concentrations (between 800 and 2000 ppm) of the modified dicarboxylic PEG is enhanced for a short duration and that the anchoring group attached to the zinc metal is only one of the terminating carboxylate anions. The different morphologies developed on the zinc metal during exposure time is a characteristic of the modified carboxylic acid PEG inhibitor. © 2005 The Electrochemical Society. [DOI: 10.1149/1.1900963] All rights reserved.