Phenol-Formaldehyde Resin to Improve Corrosion Resistance of Zinc Layers

Abstract

The present work has the purpose to study and to evaluate the corrosion resistance of zinc layers and phenol – formaldehyde resin/Zn composite layers obtained by electrodeposition. For the best results it was used different parameters for electrodeposition such as: current density between 3 – 5 A/dm2, time for electrodeposition: 30 minutes and 60 minutes, stirring rate: 500 rpm and 800 rpm. Different sizes (mean diameter size between 0.1 – 5.0μm and 6.0 – 10.0μm) of dispersed phases were used with concentration into electrolyte solution from 10g/L to 25 g/L of polymer particles. The morphology of the layers was investigated by SEM – EDX methods. The surface morphology of composite layers was different as compared with pure zinc layers. By adding polymer particles into zinc electrolyte during electroplating a very good distribution of polymer on zinc layer surface was obtained. The electrochemical behavior of the composite layers in the corrosive environment was investigated by polarization potentiodynamic and electrochemical impedance spectroscopy methods. As electrochemical test solution 0.5M sodium chloride was used in a three electrode open cell.