Progress in Organic Coatings最新文献

The “Protein-polyphenol interactions” is a hot research topic in the field of interaction between biological macromolecules. Strong interactions between biomass polyphenolic tannins and proteins can be generated through covalent and non-covalent bonds. Inspired by this, keratin (Ker) and oxidized tannin (TA) was co-deposited on polyamide 66 (PA66) fabric to fabricate OTA/Ker coated PA66 fabric (PA66@OTA/Ker), which was then chelated with Fe³⁺ to prepare fire resistance and anti-dripping PA66 fabric (PA66@OTA/Ker@Fe). The results showed that the total heat release rate (THR), peak heat release rate (pHRR) and total smoke production (TSP) of PA66@OTA/Ker@Fe were reduced by 51 %, 57 % and 52 %, respectively. PA66@OTA/Ker@Fe had a residue char of 21.6 % at 800 °C under N₂ atmosphere. In addition, the LOI of PA66@OTA/Ker@Fe increased from 20.5 % of the control sample to 28.5 % and reached a UL-94 V-0 rating. Besides, PA66@OTA/Ker@Fe exhibited excellent UV resistance, good mechanical and anti-bacterial properties. This work provides an eco-friendly strategy for developing multifunctional PA66 fabrics.

Cotton fabric is a cellulose-based material with complex capillary spaces, which enhance breathability and softness. However, these capillary spaces can promote bacterial growth with moisture during storage and daily use. Additionally, cotton fibers are highly flammable, posing a fire hazard to wearer. The lack of inherent antibacterial and flame retardant properties in cotton fabric limits its applications. In this paper, the triazole compound containing Schiff base (NABTA) was synthesized from 3-bromopropene, p-hydroxybenzaldehyde and 3-amino-1,2,4-triazole, followed by an addition reaction between Schiff base activity and 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (DOPO) to synthesize an antibacterial and flame retardant precursor (NABTA-DOPO). The structure of NABTA and NABTA-DOPO was characterized by FTIR and NMR. NABTA and NABTA-DOPO were applied to cotton fabrics to investigate and compare their antibacterial properties and thermal stability. The results showed that all the cotton fabrics treated with NABTA and NABTA-DOPO had favorable antibacterial effects. The introduction of DOPO had no significant effect on the antibacterial effect and mechanism of the fabrics. However, it otherwise improved the burning stability of treated cotton fabrics. The antibacterial activity of 10 g/L NABTA-DOPO treated cotton fabrics after chlorination against E. coli and S. aureus was over 99.99 %. The vertical burning test results showed that cotton fabrics treated with a concentration of 50 g/L NABTA-DOPO had improved flame retardant properties with a damaged length of 5.9 cm. In addition, the storage, washability, UV stability and antibacterial reproducibility experiments demonstrated the excellent durability and reproducibility of the N-halamine structure of chlorinated cotton fabrics. This study enhances cotton fabric by synthesizing and applying NABTA and NABTA-DOPO, resulting in improved multifunctionalities, including antibacterial properties, flame retardancy, UV resistance, and wettability.

The formation and accumulation of ice on the heat exchangers of air conditioners significantly reduce the performance issues, as well as the stability and heating efficiency. Superhydrophobic anti-icing coatings passively achieve multifunctional anti-icing properties by minimizing water droplet contact and promoting Cassie ice formation. However, long-term performance in frigid environments remains challenge for these coatings due to limitations in anti-icing durability and mechanical properties. Herein, a double-layer polymer-SiC/F-SiO₂ superamphiphobic composite coating is developed. The bottom layer comprises a polymer PAI and SiC composite, and the top layer consists of F-SiO₂. The composite coating demonstrates superior performance in simultaneous frost prevention, low ice adhesion, easy frost removal, exceptional mechanical strength, and long-lasting anti-icing durability. Our developed double-layer coating exhibits low ice adhesion strength down to 9.2 kPa, remarkable mechanical resilience against scratching and flushing, and delayed frost properties. These superior anti-icing properties, manifested by both lower adhesion strength and improved frost repellency, lead to a doubling of frosting time and the easier removal of ice on coated heat exchangers compared to traditional units. The development of this novel superamphiphobic composite coating provides a practical approach to creating durable anti-icing materials, leading to significant improvements in air conditioner performance.

Photothermal superhydrophobic surfaces are prospective to become ideal anti−/de-icing surfaces because of their icing delay and rapid photothermal deicing property. Herein, a universal photothermal superhydrophobic composite coating (PSCC) was robustly sandwiched a photothermal layer based on hydrophobically modified titanium nitride (TiN) composite spherical nanoparticles (TiN@SiO₂@OTES) between polydimethylsiloxane (PDMS) double layers (the top layer acting for protection and the bottom for thermal insulation and adhesion with the substrate). Due to the high photothermal conversion efficiency (66.0 %) of TiN nanoparticles, the composite coating demonstrated a satisfactory anti−/de-icing efficiency with a stable icing delay time (690 s at 1 sun and − 10 °C) and a fast photothermal de-icing capability (120 s under 1 sun and − 10 °C). In addition, the coating could maintain super-hydrophobicity exhibiting good durability and stability in the lash of sand and water due to the multi-layer design reinforced by PDMS, which was also favorable for residue-free removal of surface to achieve the self-cleaning. Overall, the robust corrosion-resistant photothermal superhydrophobic coating showed a potential for anti−/de-icing application.

The excessive use of laundry detergents has rendered surfactants in laundry wastewater a significant threat to ecological sustainability. Increasing attention has been directed toward fluorinated amphiphilic copolymers (FACs), which impart stainproof and soil release properties to fabrics, thereby reducing the need for detergent usage. This paper describes the preparation of two soap-free FAC emulsions, H and H + G, through solution polymerization followed by solvent displacement. The incorporation of ionic and cross-linking monomers results in limited surface reconstruction of the coatings when exposed to water. However, the strong hydrophilicity of ionic monomers promotes excellent water-induced surface hydrophilism (Δγ_s-H = 2.07 mN/m, Δγ_s-H+G = 1.60 mN/m). Upon studying the finished fabrics, the beneficial effects of the auxiliary monomer were reaffirmed. H + Linker exhibited the best overall properties, with its coating evenly distributed across the fabric fibers without substantially blocking the inter-fiber gaps. Fabrics coated with H + Linker demonstrated excellent stainproofing, soil release performance, and washing resistance (for corn oil, S.R.R._5-cotton = 4+, S.R.R._{5-polyester pongee} = 4−), as well as outstanding wear resistance (the water contact angle remained above 136° after 200 wear cycles). Analysis of fabric stain penetration led to a summarized mechanism for soil release: first, the coating must uniformly cover the fabric fibers to block external dirt; secondly, the coating surface must achieve the water-induced hydrophilization, facilitating improved cleaning. This mechanism underscores the validity of developing FACs to create durable, soap-free coatings for stainproof and soil release fabrics, which can satisfy practical application needs and mitigate the excessive use of surfactants.

Due to the vast applications in biomedical materials and aerospace industry, smart slippery liquid-infused porous surfaces (SLIPSs) have attracted remarkable attention. However, there are still challenges in the fabrication of durable SLIPS. In this work, based on linear polyurea and silicone oil, a series of durable anti-icing surface were fabricated. Based on the long-lasting secretion of lubricant, the ice adhesion strength of 60-PUa was 2.7 ± 0.5 kPa and could remain below 10 kPa even after 30 icing-deicing cycles. And the icing delay time of 60-PUa could be extended up to 870 s at a temperature of −15 °C. The introduction of large numbers of reversible hydrogen bonds in the system and silicone oil made it possible to achieve high self-healing efficiency under natural conditions. The coating system not only improved the ice removal ability, but also had excellent water-sliding properties, the droplet could slide under its own weight on 60-PUa at a tilt angle of 4.7°. This work provides an easy way to fabricate multi-functional SLIPS with durability.

A metal–ligand complex is a complex antimicrobial system with a 3D morphology that diversifies its antimicrobial potency. These complexes with diverse geometries can mitigate microbial resistance to biocidal agents. However, the antimicrobial potential of such complexes has not been extensively investigated. In addition, to meet the goals of the 2030 Agenda, the demand for antimicrobial packaging systems prepared from bio-based and/or biodegradable polymers has been increasing. To this end, in this study, a zinc–melamine (MA) complex was introduced into polyvinyl alcohol (PVA) using epichlorohydrin (ECH) as the epoxide crosslinker. PVA was first modified using ECH, allowing interactions between PVA–ECH and MA. Subsequently, zinc ions were introduced into PVA–ECH–MA complex to develop a metal–ligand complex in the PVA matrix and with the solutions created, film samples were obtained with the bar-coating technique. The chemical composition of a film prepared using the metal–ligand complex was assessed through Fourier transform infrared spectroscopy, which indicated the presence of the zinc–MA complex in the PVA film. The thermal properties of the samples were verified through thermogravimetric analysis. The introduction of the complex improved the flexibility, Young's modulus, and fracture resistance of PVA. Specifically, the elongation at break increased from 89.29 ± 6.63 % to 338.67 ± 14.54 %. Additionally, the Young's modulus considerably decreased from 740.40 ± 195.15 to 2.51 ± 0.26 N/mm². Furthermore, the antimicrobial properties of the metal–ligand complex against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were evaluated using the inhibition zone assay. The metal–ligand complex film exhibited a large inhibition zone against both microbes, with a stronger effect against E. coli than S. aureus. Indeed, the inhibition zone for E. coli was around 13/14 ± 1 mm, while the positive control obtained a zone of around 7 ± 0.5 mm. Because of its significant antimicrobial efficacy and enhanced mechanical properties, the as-prepared antimicrobial film can be applied in the production of food packaging materials and coatings for food contact paper.

Although manganese-based driers with nitrogen- or oxygen-containing ligands can accelerate the surface drying of tung oil film, their mechanical property performance does not meet industrial requirements. To address this, the drying activities of manganese-based driers with nitrogen- and oxygen-containing ligands on tung oil film were investigated. The curing process of tung oil film catalyzed by the combination driers of Mn(OH)₂(benz)₂·Mn(H₂O)₂(acac)₂, MnCl₂(bipy)₂·Mn(H₂O)₂(acac)₂, and MnCl₂(bipy)₂·Mn(OH)₂(benz)₂ was revealed using Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The results revealed that the combination driers enhanced the drying activities of Mn²⁺ in tung oil due to a synergistic effect between Mn²⁺ and its ligands. This process catalyzed the crosslinking of tung oil, giving the tung oil film a faster drying time, greater scratch resistance, increased hardness, improved flexibility, and greater thermal stability. These materials may replace traditional heavy metal driers to produce tung oil films with outstanding mechanical properties. Additionally, this paper describes the drying mechanism of these manganese-based driers with a combination of nitrogen-containing and oxygen-containing ligands and provides a new tung oil drying method.

Coating is always one of the most important methods for corrosion protection, to address the problem that the coating does not have the ion-blocking ability, this paper takes modified graphene as the filler and prepares a bipolar coating with an inner layer containing cetyltrimethylammonium bromide (CTAB)-modified graphene that is cation-selective and prevents the penetration of cations such as metal ions, while the outer layer containing sodium dodecylbenzene sulfonate (SDBS)-modified graphene is anion-selective and blocks the entry of anions such as Cl⁻. The 0.01 Hz impedance modulus value of the bipolar coating with graphene addition of 0.6 wt% (Ts0.6) was 5.88 × 10¹⁰ Ω·cm² after 84 days of immersion, with no significant modulus attenuation, and five orders of magnitude elevated the modulus value compared to acrylic urethane coatings commonly used for storage tanks. Ts0.6 can withstand a minimum of 280 °C and has an adhesive strength to the substrate of 11.08 MPa. With the increased amount of graphene, its adhesion decreases, but heat resistance improves.

Employing electrostatic powder spraying technology, this research successfully devised an eco-friendly and enduring superhydrophobic coating that showcases exceptional anti-icing and de-icing characteristics without emitting volatile organic compounds (VOCs). Through the integration of polytetrafluoroethylene (PTFE) and silica dioxide (SiO₂) particles into a polyester-based powder coating, followed by thorough mixing with a domestic blender, the resultant powder was uniformly applied to the substrate via electrostatic attraction and subsequently cured to yield a mechanically robust superhydrophobic coating (CA = ~162°, SA = ~2.3°). Remarkably, the coating sustained a contact angle of approximately 150° even after enduring two cycles of water and falling-sand impact tests—equivalent to two years of natural weathering as per ISO/TS 10689 standards—as well as surviving 250 cycles of abrasion or 200 peel tests, underscoring its remarkable durability. The ingenuity of the coating's superhydrophobicity lengthened the freezing duration by 2.8-fold for a 100 μL water droplet at −20 °C. When photothermal attributes were coupled with superhydrophobicity, the freezing delay was further amplified to 3.6 times under an illumination of 0.3 kW/m² and to 4.2 times under 0.6 kW/m². Moreover, the coating slashed the ice melting time by nearly half when tested under simulated sunlight (1 kW/m²) or under the influence of an infrared laser (25 kW/m²), relative to an uncoated aluminum substrate. In comparison to water droplets on aluminum, the ice adhesion force on the coated surface was diminished by 87 %. In summation, this innovative, eco-conscious, and long-lasting superhydrophobic coating, boasting superior anti-icing capabilities, holds immense promise for mass production and extensive application in the realm of outdoor metal protection.