Journal of Coatings Technology and Research最新文献

Triazole compounds are the excellent corrosion inhibitors for copper. The degree of polymerization of triazole inhibition film is an important factor influencing their anticorrosion performance. The atom transfer radical polymerization (ATRP) reaction provides an effective method to synthesize the polymer with controlled degree of polymerization. In this work, a triazole monomer of (1-tosyl-1H-1,2,3-triazol-4-yl) methyl acrylate (TTMA) is synthesized via the CuAAC (Cu(I)-catalyzed azide-alkyne cycloaddition) “click chemistry” reaction between propynyl acrylate and p-toluenesulfonyl azide. The triazole polymer (P-TTMA) with different degree of polymerization (DP) is prepared by the ATRP reaction among TTMA monomers. The DP value of P-TTMA polymer is regulated by varying the [monomer]/[initiator] ratio in ATRP reaction. The P-TTMA polymer is assembled on copper surface by self-assembling method to form P-TTMA inhibition film protecting copper from corrosion. The electrochemical measurement results indicate that P-TTMA films show excellent protection performance for copper in 3.5 wt% NaCl solution. Their protection performance for copper is related to the DP value of P-TTMA polymer. Within a certain range of DP value, the anticorrosion performance of P-TTMA film increases with the DP value increasing. But when the DP value is too large, the anticorrosion performance of P-TTMA film decreases, contrarily. When the DP value of P-TTMA polymer is 56, the obtained P-TTMA film shows the best protection performance; its protection efficiency for copper is 95.6%. The relationship between the degree of polymerization of P-TTMA polymer and its adsorption behavior on copper surface is discussed via surface analysis and molecular dynamics (MD) simulation. The results reveal that the [monomer]/[initiator] ratio variation can yield P-TTMA with different DP values, which can form the different P-TTMA films on copper surfaces. The protection of P-TTMA film for Cu is mainly achieved via the coordination between triazole ring, O atoms in P-TTMA molecule with Cu, and the intermolecular interaction between P-TTMA molecules and Cu. The DP of P-TTMA can affect the conformation and adsorption behavior of P-TTMA film on copper surface, influencing the protection performance of P-TTMA film for copper.

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Renewable functional coatings, crafted from sustainable resources, are revolutionizing materials science by combining advanced performance with eco-friendly attributes. These coatings, derived from bio-based feedstocks like natural oils, biopolymers, and microbial resources, provide essential functionalities, including corrosion resistance, antimicrobial activity, self-healing, and hydrophobicity, while reducing environmental impacts. Widely applied across industries such as automotive, electronics, and healthcare, they enhance durability, safety, and sustainability. Advanced characterization techniques have unveiled critical insights into their structures and properties, optimizing their development and application. The integration of renewable materials addresses global challenges by decreasing reliance on fossil-derived coatings, minimizing carbon footprints, and promoting resource efficiency through life cycle assessments. Despite challenges in balancing performance and sustainability, breakthroughs in formulation and multifunctionality continue to propel this field forward. This review highlights the transformative potential of renewable-based coatings, underscoring their role in fostering innovation and resilience in modern materials science. Through sustainable approaches and green chemistry principles, these coatings exemplify a paradigm shift toward a sustainable, high-performing future.

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The aim of this study is the development of photocurable phosphorus-containing coatings based on soybean oil as a promising green alternative with higher bio-content to conventional heat and VOC-based metal coatings. Considering this aim, acrylic acid (AA) and a reactive monomer containing phosphorus (Sipomer PAM-200) reacted with the epoxide groups of epoxidized soybean oil (ESBO). The synthesized AA modified ESBO (A-ESBO) and Sipomer PAM-200 modified ESBO (S-ESBO) oligomers were then chemically characterized using Fourier transform infrared and proton nuclear magnetic resonance (¹H NMR) spectroscopies. Photocured free films of these oligomers were evaluated by means of hardness, mechanical, and thermal properties. Coatings were formulated by using the synthesized oligomers, photoinitiator, and reactive diluents with various functionalities, then applied on iron–silicon–aluminum (Al) alloy surfaces, and cured by UV-light. The coating quality was evaluated by contact angle, water resistance, gloss, hardness, and abrasion resistance tests. The overall findings demonstrated that adding more phosphorus-containing oligomer (S-ESBO) to the coating formulation improved the thermal stability, tensile, modulus, and hardness values. This can be attributed to a number of factors, including the presence of polar hydroxyl groups in phosphate ester, the penta polypropylene glycol groups of the phosphorus-containing oligomer, and an increase in the crosslinking density of the polymeric network.

Laccase-catalyzed drying of raw lacquer (RL) is highly sensitive to ambient humidity. To reduce the dependency of RL drying on laccase, preparing synthetic laccase-like becomes crucial. Inspired by the coordination structure of laccase Cu active center, a Cu-MOF with Cu–N bonds was designed and synthesized as a laccase-like. Using a physical blending method, Cu-MOF was incorporated into RL at specific ratios to catalyze the polymerization of RL. FTIR and ¹H NMR studies were employed to investigate the effects of Cu-MOF on the particular structures of urushiol and its reaction groups under room temperature conditions. The lacquer films were characterized using FTIR, SEM, and TA, while the coatings’ physical and mechanical properties and corrosion resistance were also evaluated. The results showed that the addition of an appropriate amount of Cu-MOF effectively promoted the polymerization of raw lacquer, and the curing rate was unaffected by environmental humidity at room temperature. Furthermore, Cu-MOF improved the adhesion, hydrophobicity, thermal stability, and salt resistance of the coating. FTIR and ¹H NMR analyses revealed that Cu-MOF primarily catalyzed the oxidation of the hydroxyl group of urushiol into quinone free radicals and promoted polymerization at positions on the benzene ring and side chains. Thus, Cu-MOF plays a critical role in optimizing the drying of RL and reducing its dependence on environmental conditions.

Flexible and fire-resistant hydrogel–cotton fabric composites doped with ceramic fire retardants were obtained by the immersion method. Among the analyzed mixtures, the samples based on sodium polyacrylate, which provided the best degree of penetration and subsequent intumescence, and those containing magnesium hydroxide in their composition had the best fire-resistant parameters. This was confirmed based on TG/DSC and DMA thermal analysis, PCFC measurements, reaction to fire test results, and SEM microphotographs. The MIR spectroscopic analysis additionally proved that the fire-retardant mechanism is based on the creation of an intumescent structure strengthened by the interaction of fire retardants with various functions, such as hydroxides, which, during decomposition, create a protective char around the material. We believe that these results will contribute to the development of special fabrics with fire-retardant properties.

Glass flakes are frequently claimed to improve the resistance of organic coatings to mechanical loads. This contribution is concerned with effects of glass flake addition to multilayer organic coating systems with epoxy interlayers on their resistance against abrasive wear, compression loads and impact loads. Four pairings with two layers of epoxy and one polyurethane/polysiloxane topcoat each are manufactured and tested. Each pairing features a system with epoxy layers without glass flakes and a system with epoxy layers with glass flakes. Relevant resistance parameters for the three loading cases are introduced, namely abrasion resistance (wear), contact stiffness, damage area and first maximum force (compression), and first maximum force and deflection at maximum force (impact). The effects of glass flakes on these parameters are investigated via scanning electron microscopy (SEM) inspections and are evaluated with statistical methods. The results reveal that, statistically, glass flakes do neither significantly improve nor significantly deteriorate the resistance of the investigated coating systems against these types of loading. The effects depend on the load intensities. Three working hypotheses have been formulated to explain a possible worse performance of glass flake-reinforced epoxies under mechanical loads: 1. glass flakes introduce a weak interface (flaw) between the flake and the polymer matrix; 2. the glass flakes added to a polymer matrix act as a stiff inclusion in a soft matrix, generating stress concentrations; and 3. glass flakes reduce the capability of the composite material to plastically deform and shift the material response to a linear elastic (brittle) mode.

Blue-emissive carbon dots (CDs) were synthesized using tetraphenylethylene and benzothiadiazole carbaldehyde via solvothermal method. The as-synthesized solvothermal product was purified via column chromatography technique. Among all eluted fractions, the third fraction demonstrated blue fluorescence (λ_em = 490 nm). TEM imaging showed quasi-spherical CDs with polycrystalline nature having diameters ranging between 5 and 35 nm. Upon addition of water to the CDs dispersion the precipitate formed showed prominent blue fluorescence (λ_em = 450 nm). Further, the CDs were dispersed in hydroxyethyl cellulose, a water-soluble binder to formulate a water-based ink and was printed on UV dull paper by screen printing technique. The print proofs displayed prominent blue fluorescence (λ_em = 450 nm) with good adherence and photostability.

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In this study, epoxy resin containing hydrazone groups was cured with polyetheramine (Jeffamine D2000) and nanoparticles (carbon nanotubes, graphene, and fullerenes) to obtain new epoxy nanocomposite coatings as alternatives for epoxy coatings for metallic surfaces. In the initial stage, hydrazone was synthesized, and the epoxidation reaction was carried out with EPC (epichlorohydrin). Subsequently, the newly formulated hydrazone-based epoxy resin was cured with polyetheramine (Jeffamine D2000) and nanoparticles (carbon nanotubes, graphene, and fullerenes) at varying temperatures (25–120°C) to yield novel epoxy nanocomposite coatings. The characterization of the resins and coatings was conducted through a combination of nuclear magnetic resonance, Fourier transform infrared spectroscopy, and differential scanning calorimetry (DSC) analysis. The DSC results indicate that the cured films have glass transition temperatures approximately 107°C. The amine-cured epoxides were obtained with fairly high Tg values and good thermal stability. In addition, the mechanical properties (hardness, impact resistance, and adhesion) of the new hydrazone-based organic nanocomposite coatings obtained in this study were also examined. Furthermore, a comparative analysis was conducted between the thermal and mechanical properties of the novel epoxy coatings and their nanoparticle-containing derivatives, thereby unveiling the effect of nanoparticles on the properties of the coatings.

The interlayer adhesion of multilayer fouling release coating (FRC) systems is crucial for their durability and long-term performance. However, characterizing the adhesion of such systems, particularly the silicone-based topcoats, represents unique challenges due to their nonstick surface properties, low mechanical strength, and comparatively weak interlayer adhesion. Consequently, common adhesion test methods often fail to provide consistent and reliable measurements, leading industry to adopt more unconventional methods, which, however, require a high examiner expertise and do not provide quantitative adhesion values. In the present study, the well-known pull-off adhesion method was optimized for the quantitative adhesion measurements of multilayer FRC systems. Key optimizations comprised the selection of a suitable glue, the correct preparation of the test area and the bonding of the dolly, the pull-off rate, and a more accurate failure pattern assessment using digital image analysis. The reported pull-off method procedure allowed reproducible adhesion characterization and differentiation of the tested FRC systems. Additionally, changes in the adhesion properties and the weak spots due to altered overcoating intervals and seawater immersion were detected. By following the procedure and guidelines provided in this study, the pull-off method can be effectively applied as an objective and quantitative adhesion test for multilayer FRC systems.

Fast UV-curable coatings were prepared through thiol-ene reaction in 10 s, and their waterproof performance was evaluated in different aqueous conditions. The FTIR spectra showed that UV polybutadiene (PB) coatings could be successfully prepared by using mercaptan pentaerythritol tetra (3-mercapto propionate) (PETMP) as the crosslinking agent reacting with maleic anhydride-grafted polybutadiene under photo initiator. Their gel content increased from about 78–92% with the addition of PETMP from 10% to 20%, and then, this increment was less than 2% with the addition of PETMP from 20% to 30%. Their water absorption rate decreased from about 7%–4% with the addition of PETMP up to 20%−25% after 240 h immersion in DI water. The coating containing 25% PETMP demonstrated a significant cleanliness relative to that of plywood and the other coatings as observed from the stain flushing test. The EIS impedance after 96 h immersion revealed a great enhancement in corrosion resistance with the addition of PETMP at about 20%–25%, while the decline in impedance for the coating with 30% PETMP implied the probable aggregation of excessive PETMP; these were confirmed by the semi-immersion test in which the sample containing 20% PETMP exhibited much better salt water resistance than that of the other samples after 168 h immersion in 3.5% NaCl solution. An appropriate addition of PETMP at around 20%–25% resulted in a high crosslinking degree that enhanced waterproof performances of UV-cured PB coatings in DI water, stain water, and salt water. This study provides valuable reference in designing fast UV-curable coatings with good water resistance used as electronic packaging sealants, flexible protective coatings, and so on.