Fabrication of excellent anti-corrosion epoxy coating based on GON-An composites

ABSTRACT

Polyaniline/graphene oxide (GON-An) composites were synthesized by chemically grafting p-phenylenediamine (PPDA)-modified graphene oxide (GO) with polyaniline (PANI), which was confirmed by FT-IR, XRD, SEM, TEM, Raman spectroscopy, and XPS analyses. The electrochemical impedance spectroscopy test, brine immersion, and Tafel slopes analysis revealed that compared with GO and PPDA-modified GO (GON), GON-An composites which combined the unique corrosion resistance of both PANI and GO exhibited relatively obvious superiority in improving the corrosion resistance of epoxy coating with the same contents. After being immersed in brine for 35 days, the composite epoxy coating containing 1 wt-% of GON-An(1:2) composites in which the mass ratio of GO and PANI was 1:2, possessed a high impedance of 4×10⁹ Ω cm², a high corrosion potential of −0.25 V, and a low corrosion current of 4.119×10⁻¹¹ A cm⁻². Furthermore, the anti-corrosive mechanisms of PANI/GO epoxy coatings were discussed.

KEYWORDS:

• Epoxy coating
• graphene oxide
• polyaniline
• anti-corrosive properties

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported the National Natural Science Foundation of China [grant number U1805253], Science and Technology Project of Fujian Province [grant number 2018HZ0001-1], and Xiamen Municipal science and technology project [grant number 3502Z20171002].