Waterborne reduced graphene oxide dispersed sebacic acid modified soy epoxy nanocomposite: A green and sustainable approach for high performance mechanically robust anticorrosive coatings

Abstract

The waterborne soy oil epoxy (WSOE) has attracted significant interest due to its eco-friendly and low or no volatile organic compounds (VOCs) being free. Further, it is one of the promising precursors used to formulate low-cost, eco-friendly, high-performance anti-corrosive coatings. Because of this, the present study reports the synthesis of waterborne soy epoxy and its nanocomposite coatings formulation using soy oil epoxy and sebacic acid as a modifier (a green bio-based precursor) and reduced graphene oxide (RGO) nanofillers. The sebacic acid was used to modify waterborne oleo epoxy through salt formation, making the epoxy more bio-compatible and environment-friendly. The structural characterization of these materials was performed using X-ray diffraction, proton and carbon thirteen-NMR, and Raman spectroscopies (XRD, FT-IR, 13CNMR, 1HNMR, Raman). The graphene-epoxy nanocomposite coatings have exhibited superior thermal, physicomechanical, and corrosion protective (impedance = 106 Ω cm2 and phase angle = 78o) properties. The potentiodynamic polarization and electrochemical impedance spectroscopy techniques were used to investigate the anticorrosive activities of nanocomposite and soy epoxy coatings. The physicomechanical studies on nanocomposite coatings have displayed excellent performance i.e. Impact resistance (150 lb./in.), scratch resistance (11 kg) and MEK tests (>400 cycles), and superior corrosion protective properties as compared to those of soy epoxy and other such reported coating systems.