Journal of Coatings Technology and Research最新文献

After powders of three rare earth iodates (Ce(IO₃)₄, Ce(IO₃)₃, δ-La(IO₃)₃) were dispersed in water, the constituent ions were eluted. After filtration, polyvinyl alcohol was dissolved in the filtrated solution. Then the solution was flow-coated to form coating films on glass substrates. The obtained coating films exhibited high transmittance in the visible wavelength range. IO₃⁻ was confirmed from the IR spectra measured using the ATR method. Fine precipitates were observed in the coating. The amount was greater on the surface than inside. The coating films prepared from Ce(IO₃)₃ and δ-La(IO₃)₃ possessed high antibacterial and antiviral activities against Escherichia coli, Staphylococcus aureus, bacteriophage Qβ, and bacteriophage Φ6 in the dark. Moreover, they inactivated viruses adsorbed from the gas phase.

Using nanocontainers filled with corrosion inhibitors is an efficient strategy to create a high-performance coating that protects metals from corrosion. In this paper, Metal organic framework (MIL-88) was synthesized and loaded with a sustainable and eco-friendly corrosion inhibitor, 2-chloromethylbenzimidazole (2-CBI). The 2-CBI@MIL-88 was used as a nanofiller to prepare an epoxy resin composite coating. The results showed that the corrosion inhibitors in 2-CBI@MIL-88 were released sustainably in an acidic 3.5 wt% NaCl solution. Notably, the |Z|_0.01 Hz of the intact EP + 1% 2-CBI@MIL-88 was significantly higher than that of EP, while the |Z|_0.01 Hz of scratched EP + 1% 2-CBI@MIL-88 increases upon immersion in a 3.5 wt% NaCl solution, demonstrating the excellent self-healing ability. Overall, incorporating 2-CBI@MIL-88 into epoxy coatings offers a promising approach for enhancing the corrosion resistance of steel structures.

In order to fully utilize the whole spectrum of UV–Vis light and eliminate the problems of organic photoinitiators in the photo-curable coatings, inorganic composited photoinitiators of ZnO and Fe₂O₃ nanoparticles (NPs) were prepared and added into the photo-curable waterborne polyurethane acrylates. The inorganic composited photoinitiators utilized both the ultraviolet and visible light, which easily extended the light absorption range of each photoinitiator of ZnO and Fe₂O₃ NPs. Fourier transform infrared spectroscopy, scanning electron microscopy, and ultraviolet–visible spectrophotometer were used to characterize the chemically composited particles, physically mixed particles, and their photo-curable coatings. Comparison with the pure waterborne polyurethane acrylates, better photoinitiation effect, light conversions, and mechanical properties of the photo-cured films were obtained when the chemically composited photoinitiators of ZnO and Fe₂O₃ NPs were added with a molar ratio of 1:1. The photo-curing kinetics characterized by the UV–Vis and FTIR spectroscopy also proved their improved synergistic photoinitiation effects. This study demonstrated that the chemically composited photoinitiators of ZnO and Fe₂O₃ NPs were a prospective solution to the complete utilization of illumination light during the conventional photo-curing processes.

Surface modification of metal oxide nanoparticles can enhance their dispersibility in polymer matrix. In this study, the zinc oxide (ZnO) nanoparticles (NPs) were organically modified by coupling agent as isopropyl tri (dioctyl phosphate) titanate (KR-12) with the initial content of 3 wt.% (in comparison with ZnO NPs weight). The characteristics of modified ZnO (m-ZnO) NPs, namely chemical changes, zeta potential, morphology, and thermal behavior, were evaluated using IR spectroscopy, DLS, SEM, and TGA methods, respectively. The obtained results suggested that ZnO NPs were modified successfully with KR-12 coupling agent. In comparison with the unmodified ZnO (u-ZnO) NPs, the m-ZnO NPs had additional functional groups and there were changes of some properties such as hydrophobic property, surface charge, and thermal stability of m-ZnO NPs. The m-ZnO NPs could disperse in epoxy resin better than the u-ZnO NPs. Therefore, the m-ZnO NPs improved the mechanical properties, chemical resistance, thermal stability, and anticorrosion protection ability of epoxy resin coating. The abrasion resistance and the adhesion of epoxy coating containing 2 wt.% m-ZnO NPs were increased about 40% and 54%, respectively. The bending resistance of epoxy resin was also enhanced, and the anticorrosion resistance of coatings was improved in the presence of m-ZnO nanoparticles.

The advancement of UV-curable coatings derived from renewable resources is of paramount importance in achieving sustainability goals for safeguarding the environment. This study aims to synthesize novel UV-curable reactive diluent by reacting bio-based adipic acid with diethanolamine, followed by functionalizing it with glycidyl methacrylate. UV-curable bio-based oligomer was prepared by a ring-opening reaction of epoxidized castor oil with acrylic acid. The chemical structures of the resulting reactive diluent and oligomer were confirmed using analytical techniques such as end-group analysis, FTIR, and 1H NMR. A series of bio-based UV-curable formulations were prepared by combining synthesized reactive diluent with the oligomer and applied on wooden substrates. The effect of incorporating different concentrations of synthesized reactive diluent ranging from 10 to 40 wt.% on the viscosity of the synthesized oligomers was investigated by studying their rheological behavior. The UV-cured coatings were further evaluated for their extent of curing, bio-content, acid, alkali, and boiling water resistance. Thermal properties of films were further characterized for TGA and DSC. Cured coating with 40 wt.% reactive diluent exhibited 86 gloss at 60°, 5H hardness, 5B adhesion, 81.27 °C glass transition temperature, and maximum thermal decomposition temperature of 454 °C. The cured coatings have shown impressive stain resistance properties.

Graphical abstract

Organic–inorganic hybrid (OIH) coatings and thin films have been established as advanced materials owing to their unique combination of properties suitable for many current and emerging end-use applications. The difficulties in the deposition of such films under desirable cure conditions limit their application space. This study presents the development of a new generation of functional oligomers designed to cure independently under various cure conditions to produce OIH coatings. Specifically, we have meticulously designed and synthesized a high-solid organosilane oligomer with polyurethane backbone structure and alkoxysilane functionality. This study investigates high-solid OIH coating systems comprised of organosilane oligomer, alkoxysilane reactive diluents, and a diverse range of blocked catalysts for their effectiveness in curing under thermal, UV exposure, and ambient temperature conditions. Furthermore, we have explored the potential to combine these curing processes, offering the coating system with plural-cure capabilities. FTIR spectroscopy has been used to track the extent of cure by tracking relative intensities of alkoxysilane groups before and after curing. A comparative analysis of coatings cured by various techniques provided valuable insights into the underlying curing mechanisms and their impact on film properties. The outcome of this study suggests that these new generation versatile OIH coatings systems can be excellent candidates for sustainable advanced coating applications.