APPLICATION OF CORROSION-INHIBITORS IN WATER-BORNE COATINGS

Modification of an acrylate-based model dispersion by different additives which should act as corrosion inhibitors during the flash-off time of the dispersion film on a mild steel surface has been investigated. It is shown that mercapto compounds with a second functional group are capable of interaction with both the substrate surface and the functional groups of the polyacrylate film. Such additives bring about sufficient corrosion inhibition without adversely affecting other properties of the acrylate dispersion. Thus coatings with pronounced barrier properties on steel sheets are built up. The corrosion protection properties of the additives in the liquid dispersion as well as in the coatings formed on steel sheets have been characterized by electrochemical impedance spectroscopy.