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This study aims to study the effect of the reinforcement of mixed CeO₂-ZrO₂ nanoparticles in the polyurethane (PU) for protection properties of steel structures.

Electrochemical techniques were used to study the anticorrosion properties of the generated PU/CeO₂-ZrO₂ nanocomposite coated steel. Dynamic mechanical testing was done to investigate the mechanical properties.

In natural seawater, Electrochemical impedance spectroscopy experiments indicated outstanding protective behaviour for the PU/CeO₂-ZrO₂-coated steel. The coating resistance of the PU/CeO₂-ZrO₂ nanocomposite coating was found to be roughly 30% greater than that of the PU coating. Scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray diffraction analyses of the coated steel surface revealed that the CeO₂-ZrO₂ was accumulated at the corrosion products, preventing the corrosion. Dynamic mechanical analysis revealed that when the nanoparticle concentration was 3 Wt.%, the PU/CeO₂-ZrO₂ nanocomposite coating had improved dynamic mechanical parameters.

The coating resistance of the PU/CeO₂-ZrO₂ nanocomposite was determined to be 2999.17 kΩ.cm². The perceived current by scanning electrochemical microscopy analysis across the PU/CeO₂-ZrO₂ coating was 1.7 nA. The PU/CeO₂-ZrO₂ nanocomposite had a good hydrophobic behaviour (WCA: 101o). The newly synthesised PU/CeO₂-ZrO₂ composite offered great barrier and mechanical properties, preventing material degradation and increase the lifespan of the coated steel. Hence, this form of coating could be used as a viable coating material for industrial purposes.

The purpose of this study is to use polybenzoxazine (Pbz) functionalized ZrO₂ nanoparticles to synthesize polyurethane (PU)-PbZ/ZrO₂ nanocomposite. The results derived from the electrochemical impedance spectroscopy (EIS) and polarization studies indicated the superior anticorrosive activity of PU-Pbz/ZrO₂ nanocomposite coatings compared to those of plain PU coatings. The decreased corrosion current was detected on the scratch of the PU-Pbz/ZrO₂ nanocomposite-coated mild steel surface by scanning electrochemical microscopy (SECM) compared to other studied coatings. The superior anticorrosive and mechanical properties of the proposed nanocomposite coatings provide a new horizon in the development of high-performance anticorrosive coatings for various industries.

The Pbz functionalized ZrO₂ nanoparticles were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA) in terms of the structural, morphological and thermal properties of these coatings. A different formulation of coatings such as PU, PU-Pbz, PU-ZrO₂ and PU-Pbz/ZrO₂ were prepared and investigated for their corrosion protection performance on mild steel in natural seawater by electrochemical techniques. The surface morphological studies were done by SEM/EDX and XRD analysis.

The superior anticorrosive property of the proposed nanocomposite coatings provides a new horizon in the development of high-performance anticorrosive coatings for various industries. Addition of Pbz wrapped ZrO₂ nanoparticles into the PU coating resulted in the blockage of charge transfer at the metal/electrolyte interface, which reduced the dissolution of mild steel. It was revealed from the SEM/EDX analysis that the formation of the corrosion products at the metal/electrolyte interface behaved as the passive layer which reduced the dissolution of steel.

The inclusion of polybenzoxazine functionalized ZrO₂ nanoparticles to the polyurethane coating reinforces the barrier and mechanical properties of PU-Pbz/ZrO₂ nanocomposite, which is due to the synergistic effect of ZrO₂ and Pbz.

This paper aims to investigate the effect of introducing nano-ceria (CeO₂) particles to the epoxy coatings on mild steel in natural seawater.

The epoxy–ceria nanoparticles were coated with mild steel using a wire-wound draw-down bar method. The effects of ceria nanoparticles on the corrosion resistance of epoxy-coated samples were analyzed using scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS).

Localized measurements such as oxygen consumption and iron dissolution were observed using SECM in natural seawater in the epoxy-coated sample. The increase in film resistance (R_f) and charge transfer resistance (R_ct) values by the addition of nano-ceria particles in the epoxy coating was measured from EIS measurements after wet and dry cyclic corrosion test. Scanning electron microscope (SEM)/energy dispersive X-ray spectroscope (EDX) analysis showed that complex oxides of nano-ceria were enriched in corrosion products at a scratched area of the coated mild steel after corrosion testing. Focused ion beam-transmission electron microscope (FIB-TEM) analysis confirmed the presence of the nanoscale oxide layers of ceria in the rust of the steel.

The tip current at −0.70 V for the epoxy–CeO₂-coated sample decreased rapidly because of cathodic reduction of the dissolved oxygen. The increase in film resistance (R_f) and charge transfer resistance (R_ct) values by the addition of nano-ceria particles in the epoxy coating were measured from EIS measurements after wet and dry cyclic corrosion test.

The presence of complex oxide layers of nano-ceria layers protects the coated steel from rusting.

The use of this nano-ceria for corrosion protection is environment-friendly.

The results of this study indicated the significant effect of nano-ceria particles on the protective performance and corrosion resistance of the epoxy coating on mild steel. The dissolution of Fe²⁺ was lower in the epoxy–ceria nanoparticle-coated mild steel than that of the epoxy-coated mild steel resulting in a lower anodic current of steel. The increase in film resistance and the charge transfer resistance showed that the nano-ceria particles and the formation of complex oxides provide better barrier protection to the coating metal surfaces.

The purpose of this paper is to review the literature on women’s entrepreneurship in emerging economies. This is a thematic review to identify patterns and trends to better understand this literature. From the analysis, this study offers ideas for useful and theoretically informed research. In addition, this paper proposes the concept of restricted agency that helps to explain the practice.

This study identifies the nature, what is interesting, what it sees as important and considers what is neglected in this literature. The analysis sought important issues, interesting directions and the potential for useful future work. Thematic analysis is ideal for messy and unstructured material such as the literature used in this study as the data set. The process is qualitative, iterative and inductive but ontologically appropriate for the socially produced knowledge of the literature.

This paper finds the literature tends towards descriptive papers. Few papers make substantial contributions to theory. Many papers reported the barriers women to encounter, reporting general and typical processes of responding to obstacles and the implications for practice. Interestingly this study perceives overcoming and sometimes using, the cultural and physical restraints of gendered entrepreneurship. This paper proposes the concept of restricted agency explaining the gendering of entrepreneurs and explains what they can do. Moreover, the concept helps explain why and what. Most promising theoretically, is how the application of this agency is slowly and contextually differently changing the rules of the game.

This study covers a large and extensive literature, so might have missed themes.

This paper starts with the notion of the “otherness” of women’s entrepreneurship. The literature is good at explaining both how and why women’s entrepreneurship is different and in effect, marginalised. This study conceptualises this gendering process as a restricted agency. Moreover, the concept helps explain why and what. Most promising theoretically, is how the application of this agency is slowly and contextually differently changing the rules of the game. It may be the mechanism for emancipation.