Polydopamine Modified Graphene Oxide-TiO2 Nanofiller for Reinforcing Physical Properties and Anticorrosion Performance of Waterborne Epoxy Coatings.

Nano-polydopamine-graphene oxide-TiO₂ (nano-PDA@GO-TiO₂) composites were prepared by dopamine modified graphene oxide (GO) and loaded nano-TiO₂ on the surface of GO. The structure and morphology of nano-PDA@GO-TiO₂ composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman, X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM), and Transmission electron microscope (TEM) Results demonstrate that the introduction of dopamine to functionalize the GO could self-polymerize polydopamine (PDA) on the surfaces of the GO and endow abundant chemical groups reduce the GO. The interaction between the GO and nano-TiO₂ particles could prevent graphene nanosheets from restacking and nano-TiO₂ particles from agglomeration. Nano-PDA@GO-TiO₂ composite material was used as the nano-filler, and nano-PDA@GO-TiO₂ composites waterborne epoxy resin coatings (PGT/WEP) were prepared by dispersing a different content of nano-PDA@GO-TiO₂ composites into waterborne epoxy resin with the help of ultrasonic dispersion and mechanical agitation. The physical properties of PGT/WEP coatings, such as hardness, impact resistance, and adhesion, were tested and the electrochemical performance was evaluated. The results show that dispersing 2% nano-PDA@GO-TiO₂ composites in waterborne epoxy resin could significantly improve the physical properties and corrosion resistance of waterborne epoxy resin coating when compared with pure waterborne epoxy coating. [ABSTRACT FROM AUTHOR]