Modified GO for enhanced corrosion resistance of waterborne epoxy
In a new work, maleic acid diamine (C4H6N2O2, MAD) modified graphene oxide (M-GO) was designed as the filler, and GO/WEP composite coatings with a high cross-linking degree, improved hydrophobicity, and high barrier properties were prepared. M-GO showed a good water dispersibility and high affinity to the resin. The chemical grafting between the amino group of MAD and WEP can improve the degree of chemical cross-linking inside the coating to form a compact structure.
Electrochemical impedance spectroscopy (EIS) measurements and salt spray test results indicate that the M-GO/WEP composite coating with 0.3 wt% M-GO has the best anti-corrosion performance. After being immersed in 3.5 wt% NaCl solution for 96 h, the |Z|0.01Hz value of M-GO/WEP composite coating is 1.03 × 108 Ω•cm2, corrosion current density is 0.00040 ɥA/cm2 and the protection efficiency reaches 99.99 %.
The study has been published in Progress in Organic Coatings, Volume 172, November 2022.