Corrosion Resistance of Surface Modified Poly Vinyl Chloride Coated Steel Sheets by Electron Beam Induced Graft-Polymerization

Abstract

Corrosion resistance of surface modified poly-vinyl-chloride (PVC) coated steel sheets by electron beam induced graft polymerization and corrosion behavior was investigated. The surface modified PVC coated steel sheets by methacrylic acid (MAA modified PVC coated steel sheets) corroded slightly in the degree of white rust occurring after salt spray test.
After the specimens were dipped in the NaCl solution, SVET and A. C. impedance were measured. The MAA modified PVC coated steel sheets showed negligibly small anodic current at the cross cut area and high resistance maintained at the initial state in comparison with the non-modified PVC coated steel sheets.
It is assumed that Zn ions eluted from galvanized layer were trapped at the MAA (calboxyl group) layer in the PVC film, and this layer which showed high resistance maintained inhibition of cathodic reaction for PVC coated steel sheets.