Mohamed S. Selim
Graphene oxide nanosheets decorated with one-dimensional metal oxide composites represent hotspot materials for designing sustainable vegetable oil-based nanocomposite coatings. In this paper, we have reported that graphene oxide nanosheets decorated with β–MnO2 nanorods (GO/MnO2 hybrid) were newly synthesized via a single step chemical deposition system. Linseed oil, which meets many principles of green chemistry, was used to design biobased alkyd matrix with hyperbranched moiety via a single-step polyesterification method. An advanced ternary nanocomposite series based on linseed oil alkyd filled with GO/β–MnO2 NRs was developed via a solution casting technique, applied on carbon steel, and dried through an auto-oxidation mechanism. The structures, sizes and morphologies of designed polymeric nanocomposites and nanofillers were elucidated using various techniques such as FT-IR, NMR, XRD, FE-TEM, FE-SEM and XPS. Nano-GO with sheet-thickness Ë? 2 nm as well as single-crystalline β–MnO2 NRs with 20-30 nm mean diameter-size, Ë? 1 μm length, and exposed with grown along [110] growth orientation of wurtzite structure were synthesized through controlled regimes. Surface heterogeneity, elasticity, non-wettability and corrosion-resistance features, are among the merits of developed composite. The synergetic effects of distributing different concentrations of GO/β–MnO2 in the alkyd matrix were studied to tune the coating mechanical and protective properties. The coatings' mechanical durability and thermal resistivity were investigated using impact, mandrel bend, cross-hatch and abrasion tests as well as thermogravimetric analysis (TGA) technique. The surface and anticorrosion features of the ternary nanocomposites were studied through water contact angle, atomic force microscopy, scanning electron microscope, and salt-fog experiment (in 5% NaCl solution). The highest reinforcing improvement with thorn-like protrusions roughness was achieved through insertion of 2.5 wt. % GO/β–MnO2 NRs fillers in the matrix. This fascinating biobased nanostructure coating provides a promising alternative for replacing petro-based anticorrosive coatings for the development of a sustainable future environment
