The delamination of polymeric coatings from electrogalvanized steel -: a mechanistic approach.: Part 3:: delamination kinetics and influence of CO2

In the third part of this series of papers a kinetic analysis of the experimental data shown in Parts 1 and 2 are presented. Further experiments demonstrate the strong influence of CO2 on the delamination kinetics. For CO2 concentrations lower than 1 vol% the rate of delamination is reduced drastically without changing the reaction, between 1 vol% and 2 vol% the overall delamination rate is no longer controlled by diffusion of irons but by a charge transfer controlled O-2-reduction. The results are interpreted by thin zinc carbonate layers formed at the interface, which inhibit the rate of the ETR. (C) 2001 Elsevier Science Ltd. All rights reserved.