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1 – 10 of 89Thien Vuong Nguyen, Vy Do Truc, Tuan Anh Nguyen and Dai Lam Tran
This study aims to explore the synergistic effect of oxide nanoparticles (ZnO, Fe2O3, SiO2) and cerium nitrate inhibitor on anti-corrosion performance of epoxy coating. First…
Abstract
Purpose
This study aims to explore the synergistic effect of oxide nanoparticles (ZnO, Fe2O3, SiO2) and cerium nitrate inhibitor on anti-corrosion performance of epoxy coating. First, cerium nitrate inhibitors are absorbed on the surface of various oxide nanoparticles. Thereafter, epoxy nanocomposite coatings have been fabricated on carbon steel substrate using these oxide@Ce nanoparticles as both nano-fillers and nano-inhibitors.
Design/methodology/approach
To evaluate the impact of oxides@Ce nanoparticles on mechanical properties of epoxy coating, the abrasion resistance and impact resistance of epoxy coatings have been examined. To study the impact of oxides@Ce nanoparticles on anti-corrosion performance of epoxy coating for steel, the electrochemical impedance spectroscopy has been carried out in 3% NaCl solution.
Findings
ZnO@Ce3+ and SiO2@Ce3+ nanoparticles provide more enhancement in the epoxy pore network than modification of the epoxy/steel interface. Whereas, Fe2O3@Ce3+ nanoparticles have more to do with modification of the epoxy/steel interface than to change the epoxy pore network.
Originality/value
Incorporation of both oxide nanoparticles and inorganic inhibitor into the epoxy resin is a promising approach for enhancing the anti-corrosion performance of carbon steel.
Yang Liu, Qian Zhang, Jialing Wang, Yawei Shao, Zhengyi Xu, Yanqiu Wang and Junyi Wang
The purpose of this paper is to enhance the compatibility of titanium dioxide in epoxy resins and thus the corrosion resistance of the coatings.
Abstract
Purpose
The purpose of this paper is to enhance the compatibility of titanium dioxide in epoxy resins and thus the corrosion resistance of the coatings.
Design/methodology/approach
In this work, TiO2 was modified by the mechanochemistry method where mechanical energy was combined with thermal energy to complete the modification. The stability of modified TiO2 in epoxy was analyzed by sedimentation experiment. The modified TiO2-epoxy coating was prepared, and the corrosion resistance of the coating was analyzed by open circuit potential, electrochemical impedance spectroscopy and neutral salt spray test.
Findings
High-temperature mechanical modification can improve the compatibility of TiO2 in epoxy resin. At the same time, the modified TiO2-epoxy coating showed better corrosion resistance. Compared to the unmodified TiO2-epoxy coating, the coating improved the dry adhesion force by 61.7% and the adhesion drop by 33.3%. After 2,300 h of immersion in 3.5 Wt.% NaCl solution, the coating resistance of the modified TiO2 coating was enhanced by nearly two orders of magnitude compared to the unmodified coating.
Originality/value
The authors have grafted epoxy molecules onto TiO2 surfaces using a high-temperature mechanical force modification method. The compatibility of TiO2 with epoxy resin is enhanced, resulting in improved adhesion of the coating to the substrate and corrosion resistance of the coating.
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Yang Liu, Jialing Wang, Huayang Cai, Yawei Shao, Zhengyi Xu, Yanqiu Wang and Junyi Wang
Epoxy zinc-rich coatings are widely used in harsh environments because of the long-lasting cathodic protection of steel surfaces. The purpose of this paper is to use flake zinc…
Abstract
Purpose
Epoxy zinc-rich coatings are widely used in harsh environments because of the long-lasting cathodic protection of steel surfaces. The purpose of this paper is to use flake zinc powder instead of the commonly used spherical zinc powder to reduce the zinc powder content.
Design/methodology/approach
In this paper, the authors have prepared an anticorrosive zinc-rich coating using a flake zinc powder instead of the conventional spherical zinc powder. The optimal dispersion of scaly zinc powder in zinc-rich coatings has been explored by looking at the surface and cross-sectional morphology and studying the cathodic protection time of the coating.
Findings
The final epoxy zinc-rich coating with 35 Wt.% flake zinc powder content was prepared using sand-milling dispersions. It has a similar cathodic protection time and salt spray resistance as the 60 Wt.% spherical zinc-rich coating, with a higher low-frequency impedance modulus value.
Originality/value
This study uses flake zinc powder instead of the traditional spherical zinc powder. This reduces the amount of zinc powder in the coating and improves the corrosion resistance of the coating.
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Rania Abdel Gwad Eloriby and Hamdy Mohamed Mohamed
This study aims to assess the efficacy of nano-alumina (nano-Al2O3) in improving the performance of epoxy adhesives used to assemble archaeological glass. The conservators face a…
Abstract
Purpose
This study aims to assess the efficacy of nano-alumina (nano-Al2O3) in improving the performance of epoxy adhesives used to assemble archaeological glass. The conservators face a significant problem in assembling this type of artifact. Therefore, the assembling process is considered one of the important stages that must be taken care of to preserve these artifacts from damage and loss.
Design/methodology/approach
To evaluate the stability of adhesives, the samples were subjected to artificial aging under varying environmental conditions. Some investigative techniques and mechanical testing were used in this study to evaluate the selected materials. It includes a transmission electron microscope, X-ray diffraction, visual assessment, digital microscope, scanning electron microscopy (SEM), color change and tensile strength test.
Findings
The visual evaluation and the digital microscope results showed that the epoxy/nano-Al2O3 greatly resisted artificial aging. Although slight yellowing was present, it did not significantly affect the general appearance of the samples. On the other hand, the pure epoxy sample showed cracks of different sizes on its surface due to aging, as evidenced by SEM examination. Furthermore, epoxy/nano-Al2O3 has a better tensile strength (11.27 MPa) and slight color change (ΔE = 2.06).
Originality/value
The main objective of the experimental study was to identify appropriate adhesive materials that possess key properties such as non-yellowing and improved tensile strength by conducting various tests and evaluations. Ultimately, the goal was to identify materials that could serve as effective adhesives for assembling the archaeological glass.
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Yajun Chen, Zehuan Sui and Juan Du
This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain…
Abstract
Purpose
This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain literature review supports and development direction suggestions for future research on intelligent self-healing coatings in aviation.
Design/methodology/approach
This mini-review uses a systematic literature review process to provide a comprehensive and up-to-date review of intelligent self-healing anti-corrosion coatings that have been researched and applied in the field of aviation in recent years. In total, 64 articles published in journals in this field in the last few years were analysed in this paper.
Findings
The authors conclude that the incorporation of multiple external stimulus-response mechanisms makes the coatings smarter in addition to their original self-healing corrosion protection function. In the future, further research is still needed in the research and development of new coating materials, the synergistic release of multiple self-healing mechanisms, coating preparation technology and corrosion monitoring technology.
Originality/value
To the best of the authors’ knowledge, this is one of the few systematic literature reviews on intelligent self-healing anti-corrosion coatings in aviation. The authors provide a comprehensive overview of the topical issues of such coatings and present their views and opinions by discussing the opportunities and challenges that self-healing coatings will face in future development.
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Youssef L. Nashed, Fouad Zahran, Mohamed Adel Youssef, Manal G. Mohamed and Azza M. Mazrouaa
The purpose of this study is to examine how well reinforced concrete structures can be shielded against concrete carbonation using anti-carbonation coatings based on synthetic…
Abstract
Purpose
The purpose of this study is to examine how well reinforced concrete structures can be shielded against concrete carbonation using anti-carbonation coatings based on synthetic polymer.
Design/methodology/approach
Applying free radical polymerization, an acrylate terpolymer emulsion that a surfactant had stabilized was created. A thermogravimetric analysis, minimum film-forming temperature, Fourier transform infrared spectroscopy and particle size distribution are used to characterize the prepared eco-friendly water base acrylate terpolymer emulsion. Using three different percentages of the acrylate terpolymer emulsion produced, 35%, 45% and 55%, the anti-carbonation coating was formed. Tensile strength, tensile strain, elongation, crack-bridging ability, carbon dioxide permeability, chloride ion diffusion, average pull-off adhesion strength, water vapor transmission, gloss, wet scrub resistance, QUV/weathering and storage stability are the characteristics of the anti-carbonation coating.
Findings
The formulated acrylate terpolymer emulsion enhances anti-carbonation coating performance in CO2 permeability, Cl-diffusion, crack bridging, pull-off adhesion strength and water vapor transmission. The formed coating based on the formulated acrylate terpolymer emulsion performed better than its commercial counterpart.
Practical implications
To protect the steel embedded in concrete from corrosion and increase the life span of concrete, the surface of cement is treated with an anti-carbonation coating based on synthetic acrylate terpolymer emulsion.
Social implications
In addition to saving lives from building collapse, it maintains the infrastructure for the long run.
Originality/value
The anti-carbonation coating, which is based on the synthetic acrylate terpolymer emulsion, is environmentally benign and stops the entry of carbon dioxide and chlorides, which are the main causes of steel corrosion in concrete.
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Dongdong Song, Wenxiang Qin, Qian Zhou, Dong Xu and Bo Zhang
The anticorrosion coatings used in marine and atmospheric environment are subjected to many environmental factors. And the aging failure has been puzzling researchers. The purpose…
Abstract
Purpose
The anticorrosion coatings used in marine and atmospheric environment are subjected to many environmental factors. And the aging failure has been puzzling researchers. The purpose of this study is to find the correlation between the initial aging of epoxy coatings and the typical marine atmospheric environmental factors.
Design/methodology/approach
The epoxy coatings were subjected to a one-year exposure in three typical marine atmospheres. Meanwhile, principal component analysis, linear regression and Spearman and gray correlation analysis were applied to quantify the environmental characteristics and establish correlations with the coating aging.
Findings
The results indicate that the coating will undergo macroscopic fading and chalking upon exposure to the marine atmosphere, while microscopic examination reveals holes, cracks and partial peeling. The adhesion performance and electrochemical properties of the coating deteriorated with prolonged exposure, coating aging mainly occurs with the generation of O-H bonds and the breakage of molecular chains such as C-N and C-O-C. The coating was most deeply aged after exposure to the Xisha, followed by Zhoushan and finally Qingdao. Environmental factors affect the photooxidative aging and hydrolytic degradation processes of coatings and thus coating aging. To further demonstrate the correlation between environmental factors and coating aging, principal component analysis was used. The correlation model between environmental factors and coating aging was subsequently obtained. The correlation model between the rate of coating adhesion loss (E) and the comprehensive evaluation parameter of environmental factors (Z) is expressed as E = 0.142 + 0.028Z. Meanwhile, the Spearman correlation analysis and gray correlation method were used to investigate the impact of each environmental factor on coating aging. Solar irradiation, relative humidity and wetting time have the highest correlation with coating aging, which are all above 0.8 and have the greatest influence on coating aging; wind speed and temperature have the smallest correlation with coating aging, which are about 0.6 and have the least influence on coating aging.
Originality/value
This paper establishes a correlation between typical marine environmental factors and coating aging performance, which is crucial for predicting the service life of other coatings in diverse environments.
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Mahipal Singh and Rajeev Rathi
The present environmental concern has enforced manufacturing firms to re-evaluate their business practices to reduce the adverse impact on the environment with optimum production…
Abstract
Purpose
The present environmental concern has enforced manufacturing firms to re-evaluate their business practices to reduce the adverse impact on the environment with optimum production. Therefore, the present study aims to deal with the implementation of the environmental lean six sigma (ELSS) framework in an Indian medical equipment manufacturing industry to obtain operational and environmental sustainability.
Design/methodology/approach
The proposed ELSS framework is based on the DMAIC (Define–Measure–Analyze–Improve–Control) methodology, sustainability and lean tools. The efficacy of the developed framework is tested through a case study in an Indian medical equipment manufacturing unit.
Findings
In the case company, four major issues were reported, i.e. improper material handling, non-productive movement of men and material, poor indoor air quality and rework. The ELSS project facilitates the case organization to enhance their capacity utilization from 59.25% to 74.3%, defects per million opportunities reduce from 309,523 to 48,951.44 and indoor air quality levels decrease from 156.87 to 86.85
Research limitations/implications
The efficacy of the developed ELSS framework is evaluated through a case study conducted only in one Indian manufacturing environment.
Practical implications
The present study facilitates industrial managers and practitioners to achieve sustainability and process excellence through ELSS implementation. Organizations that intend to simultaneously improve operational and environmental performance can benefit from this paper as it can be used as a guide to conduct similar projects with both operational and environmental benefits.
Originality/value
This paper presents a successful implementation of the ELSS framework in the healthcare industry to achieve operational and environmental sustainability.
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This study aims to embed anatase, rutile and brookite TiO2 nanoparticles (NPs) with different crystal phases into cotton fabrics by epoxy silane and to examine the effect of these…
Abstract
Purpose
This study aims to embed anatase, rutile and brookite TiO2 nanoparticles (NPs) with different crystal phases into cotton fabrics by epoxy silane and to examine the effect of these applications on the photocatalytic and mechanical properties of the fabric.
Design/methodology/approach
Different aqueous dispersions which contain anatase, rutile and brookite were prepared at three different concentrations (5%, 10% and 15%). These NPs were embedded in cotton fabrics by using GPTS [(3-glycidyloxypropyl) trimethoxysilane]. Characterization tests were performed by scanning electron microscopy (SEM), Raman and Fourier-transform infrared spectroscopy (FT/IR). Samples were stained with methylene blue (MB) and then exposed to solar light for different periods. Color changes of the samples were examined with a spectrophotometer. Air permeability, abrasion and tear strength tests were applied to all samples.
Findings
According to SEM images, the NPs were successfully attached to the cotton fabrics, and epoxy silane coating surrounded the fiber surfaces. The presence of the coating was also confirmed by Raman spectroscopy and FT/IR. The treatments reduced the stainability of the samples. The most effective applications for ensuring photocatalytic activity in cotton fabrics were suspensions as 10% brookite, 10% anatase and 5% anatase, in descending order. The applied coating slightly reduced the samples’ air permeability, and wear and tear strength.
Originality/value
The importance of this study is to determine the optimal crystal phase and its concentration by using epoxy silane to ensure self-cleaning properties on cotton fabrics. The sample treated with 10% brookite is the most approached its original white color by 99.65% as a result of degradation of MB (after 120 min). On the other hand, using the pure rutile with epoxy silane was not suitable for removing MB from the fabric.
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Lan Chu, Chao Guo, Qing Zhang, Qing Wang, Yiwen Ge, Mingyang Hao and Jungang Lv
This study aims to using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscope/energy dispersive Xray spectrometer to identify…
Abstract
Purpose
This study aims to using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscope/energy dispersive Xray spectrometer to identify different automotive coatings for forensic purpose.
Design/methodology/approach
Two four-layered samples in a hit-and-run case were compared layer by layer with three different methods. FTIR spectroscopy was used to primarily identify the organic and inorganic compositions. Raman spectrum and scanning electron microscope/energy dispersive Xray spectrometer (SEM-EDS) were further used to complement the FTIR results.
Findings
Two weak and tiny peaks in one layer found between two samples by FTIR, Raman microscope and SEM-EDS verified the result of differences. The study used the three instruments in combination and found it’s effective in sensing coatings, especially in the inorganic additives.
Research limitations/implications
Using these three instruments in combination is more accurate than individually in multilayered coating analysis for forensic purpose.
Practical implications
The three different instruments all present unique information on the composition, and provided similar and mutually verifiable results on the two samples.
Originality/value
With this method, scientists could identify and discriminate important coating evidences with tiny but characteristic differences.
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