Journal of Coatings Technology and Research最新文献

Magnesium aminoclay (MgAC) has been applied for different purposes, from biological to environmental applications. Herein, we used MgAC as an additive in the water-soluble epoxy coating solution for antiradon applications. Water-soluble epoxy can fully exfoliate MgAC and has low volatile organic compounds. Results indicate that the appearance of MgAC at low concentrations increases the antiradon efficiencies of epoxy coating solution in both laboratory-scale and real-field investigations. Different techniques, including X-ray powder diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and thermogravimetric analysis, are used to investigate neat epoxy and MgAC/epoxy composites. MgAC is fully exfoliated, and its existence in epoxy does not significantly alter the structure of the epoxy coating agent. However, the amine groups of MgAC interact with an epoxide group. This reaction could lead to the absence of structural defects observed in the neat epoxy samples, thus improving its antiradon efficiencies.

The primary challenge in the development of sublimation inkjet inks lies in achieving a uniform, low particle size, and stable dispersion of pigments. This study addresses this issue by exploring the incorporation of sodium naphthalene sulfonate formaldehyde polymer (SNF) as a co-dispersant. Sublimation inkjet inks must maintain a particle size below 200 nm to ensure optimal printing behavior. The investigation focuses on the impact of SNF incorporation in the dispersion process of direct red 60 pigment and its optimum usage level. Results indicate that the presence of SNF in the formulation, at a concentration of 20% by weight of dye, optimizes ink behavior during dispersion. Comprehensive analysis techniques such as rheological characterization, turbidity monitoring over time, UV–Vis spectroscopy, filterability measurement, and dynamic light scattering analysis demonstrate the superior performance of the SNF-treated sample with SNF to dye weight ratio of 20% in achieving stable, uniform, and low particle size dispersion of pigment in the ink as well as flowability and rheological properties. However, further evaluation from the perspectives of printability and transfer yields unexpected findings. Contrary to the conventional assumption that inkjet inks with better dispersion exhibit superior overall performance in the final printing product, the SNF-treated sample with the tiniest and most uniform particle size and the highest flowability shows inferior performance in the transfer process. Colorimetric analysis of printed samples on transfer paper and polyester fabric reveals that sample with the tiniest particle sizes and the highest flowability penetrates deeper into the transfer paper, hindering their effective transfer to the fabric, especially at low transfer temperatures. In other words, while SNF exhibits a desirable effect on sublimation inkjet ink formulation, its optimal usage level must be carefully optimized, considering not only dispersion quality but also the colorimetric aspects of the final printed product. This underscores the importance of a nuanced approach to formulation optimization to achieve optimal printing performance in sublimation inkjet printing on polyester fabrics.

Shape memory alloys (SMA) treated by laser cladding (LC) offer the benefits of a controlled heat-affected zone and strong metallurgical bonding between the coating and substrate, while also reducing the residual stress typically associated with the LC process. However, their limited corrosion resistance has hindered further application and development. In this study, an organic/inorganic hybrid superhydrophobic coating was developed on the surface of Fe-Mn-Si-Cr-Ni-Nb SMA using 1H, 1H, 2H, 2H-perfluorododecyltrimethoxysilane (FDTS) as a low surface energy material, hydrophobic nano-SiO₂ to induce surface roughness, and anhydrous ethanol as a solvent. The coating retained its superhydrophobic properties even after exposure to temperatures ranging from − 70 to 200°C. It demonstrated a silver mirror phenomenon in both strong acids and deionized water, and the surface remained dry after removal from these solutions, underscoring its excellent superhydrophobic performance. Moreover, the superhydrophobic coating achieved a reduction in corrosion current density by more than half and nearly doubled the corrosion potential, marking a significant enhancement in corrosion resistance compared to uncoated SMAs. The incorporation of FDTS with nano-silica effectively addressed the inherent corrosion challenges of SMAs, providing new strategies for the preparation and modification of Fe-based SMA coatings and offering substantial support for the research and industrial production of advanced functional coatings.

Emerging autonomous driving technology has the potential to bring revolutionary changes to our society in the coming years. One key emerging technology for enabling autonomous driving is the UV-durable easy-to-clean coatings for all sensors, including vision sensors and ranging sensors, for autonomous vehicles. UV-durable hydrophobic (UVH) coatings on sensor surfaces will provide both UV durability and easy-to-clean performances. A laboratory testbed was constructed to evaluate the easy-to-clean performance of the UV-durable hydrophobic coatings on cameras, a light detection and ranging (LiDAR) system, and a radar, under laboratory-generated fouling conditions, including light rain and heavy rain, light mud and heavy mud, fog, and bugs. Several metrics such as modulation transfer function 50 loss (MTF50_loss), signal-to-noise ratio (SNR), reflectivity and the number of returned laser dots, and amplitude are used to measure the performance of sensors. The evaluation results indicate significant benefits of using UVH coatings to enhance the signal reading of sensors under inclement weather. In addition, experimental data indicated that a coating stack of UVH coatings on a sol-gel hard coat will significantly enhance UV durability. Further, UVH coatings have shown low ice adhesion, with their performance comparable to the best antiice coatings.

This study introduces a mussel-inspired superhydrophobic coating designed to enhance the long-term anticorrosion performance of copper in marine environments. Fluorine-free and fluorine-containing superhydrophobic coatings were developed by O₃-assisted pretreatment, solution polymerization of dopamine, and the Michael addition reaction of dodecyl mercaptan and perfluorooctyl ethyl mercaptan. The ozone pretreatment allows dopamine to form a denser adsorption layer on the copper surface, which improves the long-term stability of the coating. The contact angles of the two coatings are 152.8° and 155.1°, respectively. Both types of superhydrophobic coatings demonstrate good corrosion inhibition performance, particularly the fluorine-containing superhydrophobic coating (99.98%). After 28 days of simulated seawater immersion, the fluorine-containing coating still maintains high corrosion inhibition efficiency (97.02%) and good hydrophobic characteristics (140.7°), which highlight its excellent long-term seawater corrosion resistance and stability. This study provides guidelines for designing durable superhydrophobic coatings.

Superhydrophobic coatings are an answer to surface wettability challenges because they keep surfaces dry, self-cleaning, and prevent corrosion, in several areas of industrial application that require coatings with these properties. In this research work, we describe a new formulation strategy to achieve a superhydrophobic polystyrene coating that includes the combined use of SiO₂ nanoparticles and a nonsolvent. The effect of SiO₂ nanoparticles (X1, % weight), substrate temperature (X2, °C), and substrate drying time (X3, min), on the apparent static contact angle (ASCA) and the surface roughness (SR), was investigated by using response surface methodology (RSM). The optimal point predicted through RSM was confirmed experimentally, and according to the experimental values of X1 (47.0% weight), X2 (163.0°C), and X3 (64.0 min), the maximum values of ASCA and SR were 172.0° and 64.8 nm, respectively, with a slip angle of 2°. The RSM analysis indicates that the combination of the concentration of SiO₂ nanoparticles and the nonsolvent leads to better superhydrophobic behavior. SEM micrographs showed that the SiO₂ nanoparticles were randomly dispersed on the surface of the substrate. This synthesis methodology can be applied to different types of moderately heat-resistant materials.

This research aims to explore how phosphorus slag can be used to enhance both mechanical and weathering properties of the acrylic waterborne coatings. For this purpose, yellow phosphorus slag (YPS) microparticles were first modified with different loadings (1–7 wt.%) of isopropyl tri[di(octyl) phosphato] titanate (KR-12) coupling agent. Thereafter, these modified YPSs (mYPSs) were introduced into the acrylic emulsion resin (AER) matrix (at 0.5–4.0 wt.%) under sonication. Mechanical tests of AER/mYPSs coatings showed that 5 wt.% of KR-12 was an optimum loading value for modification of YPS particles. The scanning electron microscope (SEM) studies indicated a better dispersion of mYPS5 in the resin AER matrix than pure YPS particles. Accelerated weathering tests after 7–21 days of exposure indicated that the carbonyl indexes (CIs) of AER/mYPS5 coatings were lower than those of AER/YPS, and the adhesive strength of AER/mYPS5 coatings was higher than those of the AER/YPS.

Graphical abstract

The modification of yellow phosphorus slag (YPS) with isopropyl tri[di(octyl) phosphato] titanate (KR-12) coupling agent favored the better dispersion and stronger molecular interaction of mYPS than original YPS in acrylic emulsion resin (AER)

This study presents a sustainable method for producing bio-based acrylic monomers from limonene, a renewable terpene sourced from citrus peel waste. Limonene was prefunctionalized with epoxy groups first, using ultrasound-assisted epoxidation with Oxone®, an eco-friendly oxidant. A continuous mini-flow reactor was employed to epoxidize limonene to limonene oxide (LO) and limonene dioxide (LDO) with high efficiency and selectivity under mild conditions. Ultrasonic treatment improved reaction speed and reduced waste compared to traditional m-CPBA-based epoxidation methods. Full epoxidation was achieved within 20 min with 98% conversion, compared to 110 min in a batch setup. Subsequent esterification with acrylic acid produced acrylate-functionalized monomers, with 97% conversion of limonene acrylate (LA) and diacrylate (LDA) in just 2 h, significantly faster than the 20-h batch process. Finally, the exocyclic double bond of limonene acrylate was successfully epoxidized using Oxone, to yield bifunctional monomers, with quantitative conversion achieved in 11 min. This cost-effective, fast process is an important step in scaling limonene-based acrylates to employ them as sustainable alternatives to petroleum-based monomers in industrial environments.

Graphical abstract