Authors: A. Aglan, A. Ludwick and M. Reeves
Affilation: Michigan Tech, United States
Pages: 72 - 75
Keywords: corrosion, EIS, epoxy
The effect of the addition of multi-walled carbon nanotubes (MWCNT) to epoxy and vinyl chloride/vinyl acetate copolymer coatings on their ability to protect the substrates was studied. Coatings were formulated from these resins with and without MWCNT reinforcement. Steel substrates were prepared and coated with each formulated coating and submerged in 5% NaCl solution to study effectiveness by means of Electrochemical Impedance Spectroscopy (EIS). In addition, thin films from these polymers, with and without nanoreinforcement, were cast. Dogbone specimens were cut in order to study their mechanical properties. Some of these specimens were immersed in the NaCl solution for two weeks in order to compare their mechanical properties with samples not exposed to salt water. Optical microscopy was used to capture the progress of sample corrosion. EIS measurements showed that the addition of MWCNTs to epoxy and VYHH coatings increased their charge transfer resistance in comparison with the neat coatings. This is an indication of the enhanced corrosion protection of the nanocoatings. In addition, mechanical strength tests, both before and after immersion in 5% NaCl solution, showed that thin films from both epoxy and VYHH resins containing MWCNTs had improved strength, an indication of an improvement in the coatings’ cohesive properties.