▎ 摘　　要

In this research, soluble poly(o-phenylenediamine) nanoparticles were synthesized to noncovalently functionalize the graphene nanosheets via pi-pi interactions, and the corresponding protective performance of epoxy composite coatings was also investigated. Results showed that the impedance modulus of the composite coatings incorporated with 0.5-1.0% G-Popd was about 10(10) Omega cm(2) after 60 days of immersion. Furthermore, the corrosion of substrate was still retarded even if there is an artificial scratch to the composite coatings. The superior protective performance of the composite coating derived from the synergistic action in the barrier property of graphene nanosheets and metal surface passivation by Popd nanoparticles.