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Copyright of Paint & Coatings Industry (0253-4312) is the property of Paint & Coatings Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Antibacterial powder coatings have attracted increasing attention with the awakening of people's health awareness. Silver antibacterial agent has been widely used in coating system due to its superior stability and durability. However, silver ions have the problems of excessive release rate and the tendency to cause yellowing of the coating film. The addition of Cu2+ and Zn2+ can effectively alleviate these two phenomena. In this paper, the ternary exchange kinetics of Ag+, Cu2+, and Zn2+ were studied to provide a theoretical basis for the synthesis of LTA-Ag-Cu-Zn. The reaction kinetics study shows that the selectivity and the adsorption capacity of LTA to Ag+ is higher than that of Cu2+ and Zn2+. The thermodynamic analysis discovers that LTA has the highest selectivity for Ag+, and the exchange between the two is spontaneous. In contrast, the selectivity of LTA to Cu2+ and Zn2+ is concentration-dependent. By establishing the three-ion competitive adsorption curve, it is found that the selectivity of Ag+ is the highest, and the selectivity of copper and zinc is similar. These trends result from Ag+ ions' low hydration energy, small hydration radius, and strong electronegativity. This research lays the groundwork for developing high-performance LTA-Ag-Cu-Zn tri-ion exchange antibacterial agents. [ABSTRACT FROM AUTHOR]

Copyright of Paint & Coatings Industry (0253-4312) is the property of Paint & Coatings Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Protection against fire and the corrosion of metals is necessary to ensure human safety. Most of the fire and corrosion inhibitors do not meet the ecological requirements. Therefore, effective and ecological methods of protecting metals are currently a challenge for researchers. In this work, the influence of hexakis(4-(hydroxymethyl)phenoxy)cyclotriphosphazene (HHPCP) on the characteristics of powder coatings was examined. The coatings' properties were investigated by measuring the roughness, hardness, adhesion to the steel surface, cupping, gloss, scratch resistance, and water contact angle. The thermal stability was studied by furnace test and TGA analysis. The corrosion resistance test was carried out in a 3.5% NaCl solution. The distribution of phosphazene-derived segments in the coating was examined by GD-EOS analysis. Modified coatings show better corrosion and thermal resistance and can be used for the protection of the steel surface. Their better corrosion resistance is due to the electroactive properties of the phosphazene ring and its higher concentration at the coating surface, confirmed by GD-EOS analysis. The increase in thermal resistance is due to the effect of the formation of phosphoric metaphosphoric and polyphosphoric acids during the decomposition of HHCPC, which remain in the condensed char phase and play a crucial role in surface protection. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainability has increasingly become a cornerstone of the chemical industry. Sustainability metrics include low volatile organic compound (VOC) content, high efficiency, low toxicity, low energy requirements, minimal waste, recyclability, durability, and the use of renewable feedstocks. Powder coatings are well known for zero VOCs, efficient utilization, low toxicity, and recyclability. Powder coating technologists have recently ventured into the use of renewable feedstocks to synthesize binder systems. Bio-based compounds have been successfully used to produce highly sustainable powder coatings. This review presents recent research on new binder components designed for powder coatings, including: (poly(limonene carbonate)s; polyester resins; polyamide resins; and crosslinking agents (urethane-acrylates, blocked polyisocyanates). The applications of bio-based materials in powder coatings are also highlighted in this review. [ABSTRACT FROM AUTHOR]

Given the environmental benefits, poly(vinylidene fluoride) (PVDF)‐based composite powder coating was developed without using any harmful solvent. However, it still remains poor adhesion to substrates and low compatibility to acrylic resin issues. To address these challenges, PVDF was grafted with glycidyl methacrylate (GMA) through a facile and scalable reactive extrusion method. The resulting product, PVDF‐g‐GMA, was then mixed with different contents of polymethyl methacrylate (PMMA), and the mixing was sprayed onto aluminum substrates. The PVDF‐g‐GMA/PMMA powder coating shows the excellent adhesion and corrosion resistance, particularly when the PMMA content is 30 wt%, owning to the good compatibility of PVDF‐g‐GMA and PMMA. This work opens up a new possibilities for the development of advanced composite powder coatings with improved performance characteristics. [ABSTRACT FROM AUTHOR]

Based on the statistic data derived from Society of Coatings and Finishing of CIESC, National Paint and Coatings Industry Information Center, National Statistics Bureau and industrial survey, this article describes the operation situation of powder coatings industry in China during the period of 2022, and puts forward some suggestions on future development. [ABSTRACT FROM AUTHOR]

The graphene-contained materials are added during the synthesis process of polyester resin, thus a graphene modified polyester resin is prepared. It is revealed that the introduction of graphene has no effect on the synthesis process and parameters of polyester resin, in addition, has no effect on the properties of powder coatings, such as levelling property, bending property and reactivity. However, the mechanical and durability properties of powder coatings are decreased slightly. The self-made heat-radiating device is used to investigate the graphene modified powder coatings. The results show that the addition of graphene can significantly increase the heat radiation of powder coatings. Moreover, the heat radiation property increases with the increase of the film thickness in a certain range. [ABSTRACT FROM AUTHOR]

Powder coatings are a green alternative to conventional solvent-borne liquid coatings, but they have the intrinsic drawback of color-matching and adjustment in production with the conventional extrusion process. In this study, an industrially applicable approach to formulate color powder coatings utilizing ultrafine powders, i.e., a powdery blending and pressing method, was invented. This novel method was validated by comparing samples prepared by the Method 1 conventional extrusion method with an extra ultramarine pigment at 3%; Method 2 powdery blending and pressing of the original coatings and the same coating with 6% ultramarine pigment utilizing regular (coarse) powder coatings; and Method 3 utilizing ultrafine powder coatings for the two coatings with the same formulations as Method 2. The coating powders were prepared to have similar particle sizes and particle size distributions, with three commonly used coating binders, namely polyester-epoxy hybrid, polyester/TGIC (triglycidyl isocyanurate), and polyurethane (PU). The powders prepared by Methods 1 and 3 had similar flow abilities in terms of angle of repose (AOR) and avalanche angle (AVA). The performance of the new coatings by Method 3 was close to or better than the ones prepared by Method 1 in terms of the specular gloss, DOI (distinctness-of-image), reflection haze and color values, being superior to Method 2. The coatings via ultrafine powders also exhibited a comparable ultramarine particle distribution in the coating cross-sections as the conventional ones, whereas the ones via regular powders had an inferior pigment dispersion. The new method can greatly enhance the production efficiency and reduce the cost of powder coatings with compound colors, especially for small batch manufacturing.

The results of studying the density of powder coatings obtained by the electrocontact method are presented. The functional performance of coatings presents the two problems: density and strength of adhesion to the base. Review and analysis of theoretical and practical aspects of producing powder coatings resulted in deciding the prime lines of research on their density, which are related to the mechanics of their compaction on formation, establishment of basic density against pressure relations, micromechanics of the contact interaction of powder particles and surface to be hardened. The three stages of powder coating formation by the electrocontact method are recognized: powder precompaction, second compaction and preheating, sintering. The dominant processes are cold molding (pressing), hot pressing (sintering) or rolling. Cold molding is governed by the density-pressure relation, which was viewed in the context of the discrete powder nature concept, based on the analysis of contact interaction and deformation conditions of single powder particles. Phenomenologically, molding of powder materials under pressure at high temperatures (hot pressing or rolling) results in the change of linear dimensions of a porous powder body, which is appropriate for consideration as a rheological process, i.e., change of the form and volume of the dispersed system with time. The kinetics for powder particles in contact and their interfacial (base) contact is presented. In the coating formation, powder particles are bonded to the base as a result of their deformation, mechanical cohesion, adhesion, and welding in between and with the base. The interpolation equation that describes the powder layer compaction on its formation by the electrocontact method (coating density against pressure whereby the tool electrode compacts the powder layer) is proposed. Theoretical and experimental results for the powder coating density related to the pressure of their formation by the electrocontact method were obtained. [ABSTRACT FROM AUTHOR]

The potential of wastewaters from the galvanic industry treated to remove toxic heavy-metal contaminants for the manufacture of commercial products lies in the development of processes for their reuse. This research addresses the feasibility of employing galvanic waste in the production of powder coatings. Powder waste generated through the resource-saving ferritic method and electroerosion dispersion method is significantly safer for the environment than that generated through reagent methods. Coatings resulting from wastewater treatment exhibit mechanical properties that meet current industry standards. The introduction of 15 wt.% spent polyvalent iron oxide sorbent into paint coatings enhances their mechanical performances. Specifically, the rebound strength increases from 20 to 40 cm/kg and tensile strength from 5 to 7.4 mm, the bending strength decreases from 8 to 5 mm, and the corrosion resistance of the coatings improves by 1.5 times compared to the standard samples. These improvements are attributed to the introduction of chemically and thermally stable crystalline phases possessing ferromagnetic properties into the coatings. As a result, these coatings increase shielding against electromagnetic radiation in the megahertz range by three times compared to the standard coatings. A significant research finding is the potential for reusing ferromagnetic waste from the galvanic industry in specialized materials. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Today, reducing the use of volatile organic compounds is one of the most important issues for environmental protection. Since the 1950s, powder coatings have been widely considered in the surface coating field, especially pipelines, households, and office appliances, due to their environmental friendliness and excellent performance. These types of coatings are solid and they are applied to the surface in the form of powder using different methods such as electrostatic or fluidized bed and then they are cured by heat. In this study, a brief history of the development of powder coatings is described, and it is continued by full report on the types of powder coatings, their production methods and processes, and the research process, emphasizing the type and characteristics of the resins used in this industry. Considering the importance of powder resins in the formulation of powder coatings, the performance of various thermoplastic and thermosetting resins used in these powder coating systems, including polypropylene, polyethylene, poly(vinyl chloride), fluoropolyethylene, nylon, epoxy, polyester, polyurethane, acrylic, cellulose acetate butyrate, and recycled resins are compared. In addition, the method of application and film formation in electrostatic coatings and the factors affecting them are investigated comprehensively. Furthermore, some of the challenges and problems of this giant industry will be introduced in order to improve its quality and curing methods for to expand the applications. Finally, new technical approaches, aiming to save energy and produce more biocompatible powdered products, using infrared curing technology, curing by ultraviolet radiation, or the ability to coat sensitive-temperature surfaces by powder coating are described.

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Powder coatings are a green alternative to conventional solvent-borne liquid coatings, but they have the intrinsic drawback of color-matching and adjustment in production with the conventional extrusion process. In this study, an industrially applicable approach to formulate color powder coatings utilizing ultrafine powders, i.e., a powdery blending and pressing method, was invented. This novel method was validated by comparing samples prepared by the Method 1 conventional extrusion method with an extra ultramarine pigment at 3%; Method 2 powdery blending and pressing of the original coatings and the same coating with 6% ultramarine pigment utilizing regular (coarse) powder coatings; and Method 3 utilizing ultrafine powder coatings for the two coatings with the same formulations as Method 2. The coating powders were prepared to have similar particle sizes and particle size distributions, with three commonly used coating binders, namely polyester-epoxy hybrid, polyester/TGIC (triglycidyl isocyanurate), and polyurethane (PU). The powders prepared by Methods 1 and 3 had similar flow abilities in terms of angle of repose (AOR) and avalanche angle (AVA). The performance of the new coatings by Method 3 was close to or better than the ones prepared by Method 1 in terms of the specular gloss, DOI (distinctness-of-image), reflection haze and color values, being superior to Method 2. The coatings via ultrafine powders also exhibited a comparable ultramarine particle distribution in the coating cross-sections as the conventional ones, whereas the ones via regular powders had an inferior pigment dispersion. The new method can greatly enhance the production efficiency and reduce the cost of powder coatings with compound colors, especially for small batch manufacturing. [ABSTRACT FROM AUTHOR]

The relationship between the elastic modulus and the porosity of powder coatings has been investigated for different methods of their deposition. Porosity is the main means of assessing the quality of coatings and depends on the techniques for their production. A decrease in the elastic modulus of coatings after gas flame spraying is due to the presence of porosity to 30%, and after electric arc spraying – to 20%. The electric contact method of forming coatings makes it possible to reduce porosity to 5-6% and so to bring the value of the elastic modulus of coatings closer to that of compact materials

The morphology and properties of epoxy powder coating with two additives based on allotropic forms of carbon, diamond, and graphene oxide (GO), were studied. The effect of concentrations and preparation methods on the dispersion of GO within the polymer matrix was investigated. Two methods of introducing coating additives were investigated, to the component blend before extrusion and dry-mixed with the sieved powder. The surface roughness, abrasive wear resistance, thickness, as well as glossing of the coating were analysed depending on the type, concentration, and applied method of preparation. The study showed that the quantity of agglomerates in polymer matrix depends on the applied dispersion method. The lowest number of GO agglomerates was obtained by GO sonication before mixing of raw materials. The relationship between the content of GO in the coating and the abrasion resistance was found. The lowest abrasive wear was found for coating with 0.3% GO introduced by extrusion. Both additives, GO and diamond, in various concentrations have an impact on the coating wear resistance.

A heavy-duty anticorrosive powder coatings with its glass transition temperature (Tg2) of more than 120 °C has been developed, which can be applied and rapidly cured on the surface of duplex stainless steel pipes. By means of formula modification of different epoxy resins, curing agents and coupling agents, the problem that the Tg2 of conventional epoxy powder coatings is less than 120 °C can be solved, meanwhile the film defects such as boiling adhesion and cathodic stripping are solved. Thus, the coatings with high Tg2 can be used for the protection of the exterior surface of stainless steel pipes wherein the temperature of medium is more than 100 °C. It enriches the portfolio of anticorrosive powder coatings and widens the applications of powder coatings. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The synthesis of a furan-based bio-polyester resin was introduced, and the structure of the bio-polyester resin was characterized by FT-IR and H-NMR. The glass transition temperature (Tg) of the polyester resin was analyzed by differential scanning calorimeter (DSC). The molecular weight and distribution of polyester resin were analyzed by gel chromatography (GPC). The effects of furandicarboxylic acid (FDCA) content on physical and chemical properties, molecular weight and its distribution, glass transition temperature of bio-polyester resin were investigated. The results show that FDCA has significant effects on melting viscosity, resin color, molecular weight and its distribution, glass transition temperature of bio-polyester resin. With the increase of the content of FDCA, the melting viscosity of resin decreases, the color becomes deeper, the molecular weight distribution becomes wider and the glass transition temperature increases. The bio-polyester resin is used to prepare several powder coatings such as transparent, white high-gloss, black high-gloss and coffee sand grain powder coatings, all of which have good comprehensive properties. The bio-polyester resin can improve the water resistance of the coating film, while it might decrease the adhesion to the substrate. [ABSTRACT FROM AUTHOR]

Powder coatings represent an environmentally friendly VOC-free alternative to widely used solvent-borne zinc-rich coatings, with economic and ecological benefits. In particular, powder coatings have several advantageous properties, such as chemical resistance and mechanical strength. However, the performance and characteristics of polyester-based zinc-containing powder coatings remain unknown. In this study, the corrosion performance of polyester powder coatings containing up to 80% zinc is compared. Electrochemical and salt-spray testing results indicate that coatings formulated with 80% zinc demonstrate superior anti-corrosive properties than coatings with lower zinc dosages. Two distinct behavioral phases of the coating with 80% zinc were observed by measurements of open circuit potential (OCP) and polarization resistance (Rp) during immersion tests—a phase indicative of a barrier effect and a phase consistent with galvanic protection. The evolution of the coating was further characterized and interpreted as five stages by electrochemical impedance spectroscopy (EIS), and the mechanistic details were discussed. This UV-resistant single-layer powder coating has the potential to replace the commonly used high-VOC multi-layer liquid coating systems at a significantly lower cost. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fluorescent coatings have attracted attention due to their bright colors. However, they have fewer outdoor applications due to low stability, especially the poor weather resistance of the fluorescent pigments. In order to improve their weather resistance and maintain the excellent appearance, this study used polymer binders to coat a light shielding agent nano TiO2 on the surface of the fluorescent pigment to extend the durability. Three organic binders, polyester varnish, polyurethane varnish, and polyvinyl alcohol, were selected. Each binder was dissolved and mixed with pigments and nano TiO2 particles to make a polymer-TiO2 layer on the pigment surface. The effects of binder types and loadings were investigated and evaluated by accelerating weather test of corresponding fluorescent powder coatings. According to SEM and ash test, nano TiO2 was successfully coated on the surface of fluorescent pigments. The modified fluorescent pigment shows a strong ability to absorb ultraviolet rays, and the weather resistance of prepared coatings has been significantly improved compared with the original fluorescent powder coating. When using clear coat PE as a binder and setting the ratio of the binder to the nano TiO2 of 1:2, the UV exposure time of fluorescent powder coatings can be extended by over twelve times compared to the coatings with original pigment for the same color change. This study provides an effective approach to enhance the weather resistance of fluorescent coatings and thus expand their applications. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The investigations of tribo mechanical properties of coatings obtained with electrocontact welding of sintered powder materials and powder-polymer fillers of Russian manufacture are presented. It is proved that the introduction of antifriction components (powders of copper or tin) into filler material at a rate of 5-10 % increases the time to joints seizure by 1.5-2 and decreases by 1.5 the friction ratio. The application of powder-polymer and sintered fillers reinforced with metal grid produces a relief on the operating surface of the coating with the areas possessing minimum hardness. They are worn out more intensely and the forming herewith grooves help to keep lubricating oil on the friction surface. For the friction pair operating in abrasive wear conditions with adhesive wear elements, at welding it is recommended to use powder compositions (by weight): 80-90 % – PG-FBX6-2, 10-20 % of copper powder friction ratio (PMS-N); for wear conditions at adhesive wear: 90 % of iron powder (PZHR 3.200.28), 10 % of tin powder (PO-1); for abrasive wear conditions: 70-80 % – PG-FBX6-2, 30-20 % – VK8.

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The corrosion propagation rate during natural exposure tests of powder-coated steel and the relationship between natural exposure and accelerated cyclic corrosion testing (ISO 20340) results were investigated. Generally, during natural exposure, an initial fast increase in the corrosion area followed by a period where the corroded area grows very slowly are observed. As a consequence, the relative ranking between coating systems varies significantly as a function of test time. Correlation between natural exposure results and cyclic test results was not found; in many cases, a better performance in one test is associated with a worst performance in the other. [ABSTRACT FROM AUTHOR]