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Corrosion accounts for huge maintenance cost in the pipeline community. Promotion of protective coatings used for oil/gas pipeline corrosion control, in terms of high corrosion resistance as well as high damage tolerance, are still in high demand. This study was to explore the inclusion of nanoparticle fullerene-C60 in protective coatings for oil/gas pipeline corrosion control and mitigation. Fullerene-C60/epoxy nanocomposite coatings were fabricated using a solvent-free dispersion method through high-speed disk (HSD) and ultrasonication. The morphology of fullerene-C60 particles was characterized by transmission electron microscopy (TEM), and dynamic light scattering (DLS). The data analysis indicated that the nanoparticles were effectively dispersed in the matrix. The performance of the nanocomposites was investigated through their mechanical and electrochemical properties, including corrosion potential, tensile strength, strain at failure, adhesion to substrate, and durability performance. Dogbone shaped samples were fabricated to study the tensile properties of the nanocomposites, and improvement of strength, ultimate strain, and Young’s modulus were observed in the C60/epoxy specimens. The results demonstrated that the C60/epoxy composite coatings also had improvements in adhesion strength, suggesting that they could provide high damage tolerance of coatings for engineering applications. Moreover, the electrochemical impedance spectroscopy (EIS) results generated from the accelerated durability test revealed that the developed fullerene-C60 loaded composite coatings exhibited significantly improved corrosion resistance. The nanocomposite with 0.5 and 1.0 wt.% of C60 particles behaved as an intact layer for corrosion protection, even after 200-h salt spray exposure, as compared to the control coating without nanofiller in which severe damage by over 50% reduction was observed.

The deterioration of steel rebar in reinforced concrete is a major issue that reduces RC structures’ durability and structural integrity. Significant efforts have been devoted to developing high-performance coatings to provide efficient protection of the rebar, and one promising approach is to utilize nanofiller as additives to improve the performance of polymer resins. This study aimed to improve the corrosion resistance of steel rebar by applying an epoxy coating with graphene nanoplatelets (GNPs) and silica nanopowders (NSs) as additives. The corrosion behavior of nanocomposite-coated rebars was characterized via an electrochemical impedance spectroscopy (EIS) test, and salt spray exposure was utilized to evaluate the durability of the coated rebars. Investigation of abrasion resistance and mechanical properties of the coatings was conducted using the falling sand test and tensile coupon test. In addition, the nanocomposites were scanned by micro-CT to explore the effect of binary nanofillers on the intactness of the polymeric matrix. The GNP-NS hybrid filler reduced the void fraction to 0.002%, whereas the void fraction in pure epoxy was 0.07%. Significant reinforcement was found in the mechanical properties; the addition of GNP-NS hybrid filler increased the tensile strength to 37.1 MPa, a 56% increase compared to the pure epoxy. Additionally, the GNP-NS hybrid fillers have led to an improvement of 16% in the Young’s modulus. In terms of corrosion resistance, the Rc value of rebar coated with GNP-NS coating was about three times greater than the ones coated with a single-filler epoxy coating during the initial test, and this value remained undegraded after 200 hr of exposure. In contrast, the group containing hybrid fillers displayed the lowest thickness loss following abrasion testing, with a 74% reduction in thickness loss, showing the coating’s high abrasion resistance. Hence, the results reveal that GNP-NS hybrid fillers have superior wear resistance, mechanical capabilities, anticorrosion properties, and durability. This research provides valuable insights into developing and implementing high-performance polymeric material to protect steel rebars in concrete structures, therefore significantly increasing the sustainability of concrete structures.

Studies have shown that adding nanotechnology to the cementitious matrix can improve the properties of concrete. The term "nanoparticle" refers to particles that are 200 nm or smaller, and these substances are added to cementitious matrix either by dry mixing or by dispersing nanoparticles in water prior to wet mixing [3]. In comparison to cementitious composites without nanoparticles, cementitious composites with nanoparticles considerably enhanced microstructure and other mechanical properties. Adding various nanoparticles with proper