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Hydrophobic coatings were fabricated on 400-mesh 304 stainless steel by combining hydrothermal treatment and chemical modification. The hydrophobicity of the surfactant coatings was evaluated. The fabricated coatings were characterized by scanning electron microscopy, contact angle measurements and X-ray diffraction. The results revealed that a hydrophobic coating with a water contact angle of 154∘ could be successfully synthesized under specific conditions: a concentration of 0.005mol⋅L−1 C12H25SO4Na and subsequent modification with a 1mol⋅L−1 ethanol stearate solution for 24h. This outcome highlights the potential of this methodology for producing highly efficient hydrophobic coatings for stainless steel mesh substrates. [ABSTRACT FROM AUTHOR]

Edible polymers are safe for consumption by humans and use in society. Shellac is a derivative of Lac, which has been used for a long time in many different industries due to its remarkable properties, which include film-forming, water resistance, thermoplastic, adhering, bonding, and simple solubility in spirit and aqueous alkali solvents. A paradigm shift has been observed in the variety of applications and uses of shellac due to the growing desire for natural products, particularly in the food, pharmaceutical, 3D printing, stealth technology, green electronics, and intelligent sensor industries. It is commonly used as an enteric coating in the pharmaceutical sector and as a preservative coating or confectioners glaze in the food industry. Being a natural and eco-friendly substance, shellac has a great deal of potential for more sustainable technologies. Due to the film's strength and polymerization, shellac, however, has limitations. The low stability and mechanical brittleness of shellac, which result from self-polymerization reactions, limit its application even though it has great potential as an environmentally benign protective covering. This review offers a comprehensive understanding of lac, encompassing its characteristics, its uses, and its prospects for the future. This study aims to investigate a new method that may mitigate some of the disadvantages of shellac coating whilst improving the material's stability and mechanical properties. [ABSTRACT FROM AUTHOR]

Water repellency has significant potential in applications like self-cleaning coatings, anti-staining textiles, and electronics. This study introduces a novel nanocomposite system incorporating functionalized Al2O3 and CeO2 nanoparticles within a polyurethane matrix to achieve hydrophobic and UV-blocking properties. The nanoparticles were functionalized using an octadecyl phosphonic acid solution and characterized by FTIR and XPS, confirming non-covalent functionalization. Spin-coated polyurethane coatings with functionalized and non-functionalized Al2O3, CeO2, and binary Al2O3-CeO2 nanoparticles were analyzed. The three-layered Al2O3-CeO2-ODPA binary system achieved a contact angle of 166.4° and 85% transmittance in the visible range. Incorporating this binary functionalized system into a 0.4% w/v polyurethane solution resulted in a nanocomposite with 75% visible transmittance, 60% at 365 nm UV, and a 147.7° contact angle after three layers. These findings suggest that ODPA-functionalized nanoparticles, when combined with a polymer matrix, offer a promising approach to developing advanced hydrophobic and UV-protective coatings with potential applications across various industrial sectors. [ABSTRACT FROM AUTHOR]

The need for sustainable energy solutions is steering research towards green fuels. One promising approach involves electrocatalytic gas conversion, which requires efficient catalyst surfaces. This study focuses on developing and testing a hydrophobic octadiene (OD) coating for potential use in electrocatalytic gas conversion. The approach aims to combine a plasma-deposited hydrophobic coating with air-trapping micro- and nanotopographies to increase the yield of electrocatalytic reactions. Plasma polymerisation was used to deposit OD films, chosen for their fluorine-free non-polar properties, onto titanium substrates. We assessed the stability and charge permeability of these hydrophobic coatings under electrochemical conditions relevant to electrocatalysis. Our findings indicate that plasma-deposited OD films, combined with micro-texturing, could improve the availability of reactant gases at the catalyst surface while limiting water access. In the presence of nanotextures, however, the OD-coated catalyst did not retain its hydrophobicity. This approach holds promise to inform the future development of catalyst materials for the electrocatalytic conversion of dinitrogen (N2) and carbon dioxide (CO2) into green fuels.

Abstract The power line insulators are permanently exposed to various environmental pollutants such as dust and fine particles. This may lead to flashovers and therefore widespread power blackouts and heavy economic damage. One way to overcome this problem is to make the insulator surface superhydrophobic. In this research, the superhydrophobic properties of the insulators were improved by applying room-temperature cured composite coatings consisting of epoxy and hydrophobic nano-silica particles. Either octadecyl trichlorosilane (ODTS) or hexamethyldisilazane (HMDS) was used to coat the silica nanoparticles and make them hydrophobic. Then, the hydrophobic silica was added to a mixture of epoxy resin and hardener. The suspension was applied on the surfaces of a commercial porcelain insulator and cold cured at ambient temperature. The coating increased the water contact angle from 50° to 149°. Even after 244 h exposure to the UV light, the samples preserved their hydrophobic properties. The adhesion of the coating was rated as 4B according to the ASTM D3359 standard. The coating decreased the leakage current by 40% and increased the breakdown voltage by 86% compared to the uncoated sample and showed promise for making power line insulators self-cleaning.

In this paper, fluorinated polyhedral oligomeric silsesquioxanes (F-POSS) and the antimicrobial agent zinc pyrithione were deposited onto the surface of glasses by physical vapour deposition. FT-1R, SEM, and UV-Vis were used to analyze the composition, morphology, optical properties, and the antimicrobial capacity of the samples. And the antibacterial ability of the samples was evaluated through bacterial count analysis of Escherichia coli and Staphylococcus aureus. The results show that the prepared coating has a homogeneous surface with 90% transparency and 118° water contact angle. It has excellent abrasion and impact resistance, some self-repairing ability, and shows excellent stability to acid, alkali, high temperature and other harsh conditions. Meanwhile, it can achieve more than 98% bactericidal ability against both common E. coli and Staphylococcus aureus within 24 hours. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) is a popular material used in the packaging industry. However, it is vulnerable to moisture, which can affect its performance and durability. Introducing hydrophobic substances, such as tetraethyl orthosilicate (TEOS) and hexadecyltrimethoxysilane (HDTMS), on the top layer of PVA can help maintain the excellent properties of PVA under high-humidity conditions. The low compatibility of hydrophobic materials with the hydrophilic layers allows them to aggregate more easily. To overcome these issues, we focused on the effects of particle size when increasing the coating suspension's dispersibility. A carbon quantum dot (CQD) suspension is an appropriate novel solvent for hydrophobic TEOS/HDTMS coating suspensions because its particles are small and light and exhibit good dispersibility. The CQD suspension formed a smooth hydrophobic coating on the TEOS/HDTMS materials. Furthermore, the uniformly coated PVA with the CQD suspension exhibited a water contact angle of 110°. The water droplets remained intact without being absorbed, confirming the effectiveness of the surface coating facilitated by CQDs. These results suggested that CQDs improved the dispersibility and enhanced the coating quality of TEOS/HDTMS on PVA. Enhancing the hydrophobicity of PVA is ideal for applications in packaging and other fields. [ABSTRACT FROM AUTHOR]

This study explores the corrosion resistance and antibacterial properties of a PTFE + TiO2/Ag coating applied to 316 L stainless steel. To enhance adhesion, a polydopamine interlayer was chemically deposited onto the steel surface. The PTFE + TiO2 coating was subsequently applied through immersion, followed by the deposition of silver nanoparticles using a chemical method. Optimization of the polydopamine interlayer involved varying temperature, time, stirring speed, and drying parameters. The optimal conditions for the polydopamine interlayer were determined to be 60 °C for 1 h, 300 rpm stirring, and 24-h drying in a freeze dryer. Analytical results demonstrated that both the PTFE + TiO2 and PTFE/PTFE + TiO2/Ag coatings exhibited exceptional corrosion resistance, with corrosion currents of 3.3 × 10−5 and 3.2 × 10−4 μA/cm2, respectively. Antibacterial assessments showcased the remarkable ability of the PTFE/PTFE + TiO2/Ag coating, containing 5% silver content, to effectively inhibit bacterial penetration within a 6.5 mm radius. Furthermore, this coating displayed a water contact angle of 143°, classifying it as a hydrophobic coating. The photocatalytic efficiency (Rs) was determined to be 3.18 × 10−3 A/W, a performance level comparable to that of a standard UV sensor. These findings underscore the substantial enhancements in corrosion resistance, antibacterial performance, and hydrophobic characteristics achieved with the PTFE + TiO2/Ag coating, particularly through the novel optimization of the polydopamine interlayer. This coating exhibits great promise for multifunctional protective applications in diverse fields, particularly demonstrating its suitability for implants and bio-coatings. [ABSTRACT FROM AUTHOR]

The power line insulators are permanently exposed to various environmental pollutants such as dust and fine particles. This may lead to flashovers and therefore widespread power blackouts and heavy economic damage. One way to overcome this problem is to make the insulator surface superhydrophobic. In this research, the superhydrophobic properties of the insulators were improved by applying room-temperature cured composite coatings consisting of epoxy and hydrophobic nano-silica particles. Either octadecyl trichlorosilane (ODTS) or hexamethyldisilazane (HMDS) was used to coat the silica nanoparticles and make them hydrophobic. Then, the hydrophobic silica was added to a mixture of epoxy resin and hardener. The suspension was applied on the surfaces of a commercial porcelain insulator and cold-cured at ambient temperature. The coating increased the water contact angle from 50° to 149°. The samples preserved their hydrophobic properties even after 244 h exposure to the UV light. The coating adhesion was rated as 4B according to the ASTM D3359 standard. The coating decreased the leakage current by 40% and increased the breakdown voltage by 86% compared to the uncoated sample, and it showed promise for making power line insulators self-clean. [ABSTRACT FROM AUTHOR]

Fluorinated hydrocarbons are excellent building blocks for hydrophobic coatings but also yield undesirable toxicity and environmental persistence. In precision industries such as high-resolution printing, polymer brushes are a valuable tool, as they can be tuned on the nanometer scale and can impart the underlying surface with desired properties and/or functionalities. Here, we report that the beneficial properties typically associated with (partially) fluorinated polymer brush coatings can to a large degree also be achieved with their nonfluorinated counterparts. To this end, we have successfully grafted 13 poly-(alkyl methacrylate) homopolymer brushes from a flat silicon surface using surface-initiated atom transfer radical polymerization (SI-ATRP). These polymer brushes were characterized by XPS, ellipsometry, and static water contact angle measurements. They were then shown to be repeatedly self-repairing by thermal treatment at 120 °C after damage by pH 3, with longer side chains being more resistant to damage from the acid. Branching of the side chains did not significantly influence this resistance, but it lowered the static water contact angle. Some polymer brushes with intermediate side chain length displayed an increase in the contact angle over the first four cycles. This was not caused by impurities but was the result of an annealing effect that improved the packing of the side chains of the brushes. In all, these coatings are suitable, self-healing, environmentally friendly, and fully nonfluorinated alternatives for current fluorine-based hydrophobic coatings. [ABSTRACT FROM AUTHOR]

Diverse strategies were designed and evaluated for enhancement of concrete resistance to microbial-induced corrosion through refinement of concrete chemistry, pore structure, transport attributes, and amenability to microbial growth. Laboratory and insitu field experiments were implemented in order to screen different strategies. The study considered strategies involving; the use of hydrophobic additives for rendering capillary pores water-repelling; blend of pozzolans to refine the chemistry and pore system characteristics of concrete; use of polymer emulsions for refinement of concrete porosity, affinity for moisture and amenability to microbial growth; use of anti-microbial constituent for reducing the amenability of concrete to microbial growth; and incorporation of polyvinyl alcohol fibers for enhancing mechanical performance of concrete mixtures, were investigated.Test results indicate that two admixture formulations comprising of hydrophobic additive, and blend of pozzolan offer the best promise to achieve substantially enhanced resistance to microbial-induced corrosion and acid resistance in the aggressive sewer environment.

Superhydrophobic materials have found extensive applications in everyday life and various industries due to their outstanding attributes such as waterproofing, exceptional anti-corrosion and self-cleaning capabilities. Nonetheless, their limited mechanical stability hinders their widespread use on ceramic surfaces. This study aims to address these limitations by employing industrial waste porcelain powder as a raw material and co-firing technology to create a micro-rough structure on ceramic surfaces. Furthermore, the impact of this rough structure on the wear resistance and hydrophobicity of the hydrophobic coating is investigated using the finite element method. The results indicate that the mechanical stability of the hydrophobic coating experiences a more pronounced enhancement with increasing distribution density of the micron rough structure of waste porcelain powder (WPPMRS). A dense rough structure does not only reduce its concentrated stress and improve its anti-wear ability, but also reduce the concentrated stress of hydrophobic coating to improve the protection of the coating. As a result, it substantially enhances the mechanical properties and stability of the hydrophobic coating. This work will provide valuable insights into the utilization of waste porcelain powder in sustainable superhydrophobic ceramics.

Magnesium alloys have attracted attention due to their biocompatibility and biodegradability. In this work, composite coatings are developed to potentially improve the corrosion resistance of AZ91D Mg alloy in simulated physiological fluid. Cerium-based/stearic acid coatings were prepared by electrodeposition combined with a simple immersion method. The effect of stearic acid bath concentration on the contact angle and corrosion resistance of the composite coatings was evaluated. The results showed that the stearic acid treatment increased the hydrophobicity of the surfaces of the cerium-based simple coatings. The use of an appropriate stearic acid concentration is a key for the fabrication of hydrophobic surfaces. The duplex coatings were demonstrated to protect the substrate from corrosion in Ringer solution.

Abstract The use of additives, generally called DRAs (Drag Reducing Additives), has been proposed to re-duce the energy consumption in pressurized pipes. Although many research works have been conducted to analyze the effect of these additives, less attention have been devoted to the application of coatings to the pipe wall. This paper demonstrates that the application of a hydrophobic coating to the pipe can lead to a head loss reduction for a transition flow regime with moderate Reynolds number values (Re). For this purpose, an experiment was conducted to compare the performance of both coated and uncoated pipes by measuring the head losses and assessing the Drag Reduction Percentage (%DR) and the pipe friction factor (f). This was done for two Polyvinylchloride (PVC) pipes with different nominal diameters (PVC90 and PVC63). In addition, the flow velocity distribution was also measured in all these tests. The %DR decreased as the Re values increased, with the reduction being notably less pronounced for higher Re values. This could be explained by the fact that a partial slip condition is induced by the hydrophobic product. Its effect is significant for a transition regime where the effect of viscosity is important, but it becomes negligible for increasing levels of turbulence. No significant differences were observed in the flow distribution between coated and uncoated pipes, which seems to indicate that the velocity change could be limited to the near-wall viscous sublayer. The results of this work open an important research line aimed at reducing energy costs and the carbon footprint in pipe fluid distribution systems.

Vegetable-tanned leather exhibits a hydrophilic character due to the abundance of hydroxyl groups (-OH). In this study, the surface of vegetable-tanned leather was modified to become hydrophobic. The leather was coated using dodecylamine (DDA) through the padding method in the finishing process. The concentration of DDA varied from 1%, 2%, 3%, and 4% to identify the optimum concentration. The coating process was assisted by an activator, either acid or base, to improve the adhesion of DDA to leather. Uncoated vegetable-tanned leather was used as a control. The success of coating was identified using FT-IR and SEM-EDX analysis. The hydrophobicity of leather was conducted through a water resistance test. The success of coating is shown by the increase in their weight and thickness. Absorption bands of alkyl and amino groups of DDA are observed in FT-IR spectra around 1450 cm-1 and 3400 cm-1, respectively. SEM micrographs show that coated leathers have flatter surfaces as a consequence of DDA attachment on the leather surface. The water resistance test proves that the use of DDA can improve the leather hydrophobicity and enhance the water absorption time by up to 4 times. The optimum water absorption time is obtained when using 2% DDA.

Steam condensation over a hybrid hydrophobic–hydrophilic surface is modeled via simplified heat transfer modelization. Filmwise condensation is assumed over the hydrophilic region. The standard film model is improved, accounting for the liquid flow rate crossing the hydrophobic–hydrophilic boundaries. A threshold for flooding occurrence is also presented. Dropwise condensation is assumed over the hydrophobic region. Compared to the heat transfer models in the literature, based on the statistical drop size distribution, a novel correlation is used for the size distribution of small droplets. The correlations of both the liquid flow rate crossing the hydrophobic–hydrophilic boundary and the size distribution of small drops are derived via Lagrangian simulations, using an in-house code previously developed and validated by the authors. The heat transfer model is validated with experimental data in the literature involving a hybrid surface, composed by alternate vertical hydrophobic–hydrophilic stripes. Then, the optimization of the hybrid surface geometry is performed in terms of hydrophobic width and hydrophilic width, with the aim of enhancing the heat flux. [ABSTRACT FROM AUTHOR]

In this study, the effect of hydrophobicity on the plate surface on heat transfer, pressure drop, and pump power was investigated without changing the existing designs of gasketed plate heat exchangers (GPHEs). The wet surfaces of the plate were coated with carbon-based polymer solutions with four different hydrophobic groups, that is, FEP, FH3, FH7, and FH10. To increase the hydrophobicity of the FEP material, a new coating solution was synthesized by adding 3, 7, and 10 wt.% h-BN nanoparticles. Heat transfer, pressure loss, and pump power performances of heat exchangers with hydrophobic surface coating were tested at five different Reynolds numbers and compared with the uncoated heat exchanger performance. Also, the efficiency analysis of the GPHE under different hydrophobic conditions was carried out. As a result, the addition of 3 and 7 wt.% h-BN nanoparticles increased the contact angle. However, the addition of 10 wt.% h-BN decreased the contact angle as it increased the rough structure and film thickness on the surface. It was determined that the heat exchanger efficiency increased proportionally with the increase in hydrophobicity. While the highest heat exchanger efficiency value was 0.525 in FH7 coated. However, it was found that there was a 25.6% decrease in heat transfer of FH7 coating compared to uncoated exchanger. The pressure drop of the FH7 surface-coated heat exchanger with the highest hydrophobicity was 207.6% lower than that of uncoated heat exchanger. Energy savings of approximately 41% were achieved in FH7 coated compared to uncoated heat exchangers. It has been emphasized that heat transfer in GPHE systems should be evaluated together with pressure drops and local losses. It was found that the use of hydrophobic surface coating on plates in heat exchangers will contribute to the development of heat exchanger designs, reducing pump costs, and energy consumption. [ABSTRACT FROM AUTHOR]

Compared with water‐soluble osteogenic drugs, fat‐soluble osteogenic drugs exhibit higher bioavailability and drug stability, making them valuable for enhancing the osseointegration of implants. However, existing drug‐loading coatings are primarily designed for water‐soluble drugs, limiting their effectiveness in loading and delivering fat‐soluble osteogenic drugs. This study employed alkali treatment, silanization, and oleic acid acylation to sequentially modify the surface of Ti alloy, aiming to fabricate surfaces capable of efficiently loading and delivering fat‐soluble osteogenic drugs. Results show that the hydrophilicity and loading capacity of fat‐soluble osteogenic drugs strongly depended on the duration of the acylation treatment. Furthermore, the drug release mechanism involved direct diffusion from the coating to the cells in contact, resulting in improved bioavailability, as opposed to diffusion into the surrounding medium and subsequent cellular uptake. In vitro experiments using vitamine D3 (VD3) as a model drug confirmed that the coating effectively promoted bone formation through the highly efficient delivery of VD3. Furthermore, in vivo experiments demonstrated that the VD3‐loaded lipophilic surface significantly enhanced osteogenic capability and improved the osseointegration of titanium implants. This study provides a promising strategy for loading fat‐soluble drugs onto Ti implants and direct experimental evidence demonstrating the significant value of fat‐soluble drugs in promoting implant osseointegration. [ABSTRACT FROM AUTHOR]

In this study, epoxy matrix composites containing mica with different particle sizes (40 and 80 µm) and quantities (0, 10, 20, 40 wt.%) were produced by the casting method. Composites were coated with a commercial agent imparting hydrophobicity in order to decrease water absorption. The bulk density and % open porosity values of the finished composites were determined by Archimedes' principle, and detailed microstructural analysis was carried out with scanning electron microscopy (SEM). The surfaces were characterized by the contact angle and roughness measurements. The durability and protective performance of the coating were quantified by the water absorption tests for various immersion times and temperatures (ASTM D570-98) and salt water resistance tests. Microstructure analysis showed that for all filler ratios and particle sizes, mica particles were homogeneously dispersed in the epoxy matrix and the mica–polymer interface was well bonded. It has been observed that the % theoretical density values of the composite products vary between 91.1 and 98.6%, and the total porosity varies between 1.4 and 8.87%. As the amount of mica increased, the total porosity also increased, regardless of the size of the mica particles. The neat epoxy matrix absorbed a higher quantity of water than composites in almost all cases, and the water absorption of the composites decreased with the increasing mica quantities and the decreasing particle size. The hydrophobic coating definitely caused the water absorption rates of the composite samples to decrease and the salt water resistance to increase, rendering them a convenient moisture- and corrosion-resistant composite material. [ABSTRACT FROM AUTHOR]

Solar cells have been developed as a highly efficient source of alternative energy, collecting photons from sunlight and turning them into electricity. On the other hand, ultraviolet (UV) radiation has a substantial impact on solar cells by damaging their active layers and, as a result, lowering their efficiency. Potential solutions include the blocking of UV light (which can reduce the power output of solar cells) or converting UV photons into visible light using down-conversion optical materials. In this work, we propose a novel hydrophobic coating based on a polydimethylsiloxane (PDMS) layer with embedded red emitting Y2O3:Eu3+ (quantum yield = 78.3%) particles for UV radiation screening and conversion purposes. The favorable features of the PDMS-Y2O3:Eu3+ coating were examined using commercially available polycrystalline silicon solar cells, resulting in a notable increase in the power conversion efficiency (PCE) by ~9.23%. The chemical and UV stability of the developed coatings were assessed by exposing them to various chemical conditions and UV irradiation. It was found that the developed coating can endure tough environmental conditions, making it potentially useful as a UV-protective, water-repellent, and efficiency-enhancing coating for solar cells. [ABSTRACT FROM AUTHOR]

The use of additives, generally called DRAs (Drag Reducing Additives), has been proposed to re-duce the energy consumption in pressurized pipes. Although many research works have been conducted to analyze the effect of these additives, less attention have been devoted to the application of coatings to the pipe wall. This paper demonstrates that the application of a hydrophobic coating to the pipe can lead to a head loss reduction for a transition flow regime with moderate Reynolds number values (Re). For this purpose, an experiment was conducted to compare the performance of both coated and uncoated pipes by measuring the head losses and assessing the Drag Reduction Percentage (%DR) and the pipe friction factor (f). This was done for two Polyvinylchloride (PVC) pipes with different nominal diameters (PVC90 and PVC63). In addition, the flow velocity distribution was also measured in all these tests. The %DR decreased as the Re values increased, with the reduction being notably less pronounced for higher Re values. This could be explained by the fact that a partial slip condition is induced by the hydrophobic product. Its effect is significant for a transition regime where the effect of viscosity is important, but it becomes negligible for increasing levels of turbulence. No significant differences were observed in the flow distribution between coated and uncoated pipes, which seems to indicate that the velocity change could be limited to the near-wall viscous sublayer. The results of this work open an important research line aimed at reducing energy costs and the carbon footprint in pipe fluid distribution systems. [ABSTRACT FROM AUTHOR]

In this study, the photothermal performance of lignin-based nanospheres was investigated. Subsequently, a photothermal actuator was prepared using lignin-based carbon nanospheres (LCNSs). The results demonstrated that LCNSs exhibited an impressive photothermal conversion efficiency of up to 83.8%. This extreme efficiency significantly surpasses that of lignin nanospheres (LNSs) and covalently stabilized LNSs (HT-LNSs). As a structural material, a hydrophobic coating was effectively engineered by LCNSs on the filter paper, achieving a water contact angle of 151.9° ± 4.6°, while maintaining excellent photothermal effects (with a temperature increment from room temperature to 138 °C in 2 s). When employing hydrophobic filter paper as the substrate for the photothermaldriven actuator, under the influence of a 1.0 W/cm2 power–density NIR laser, the material exhibited outstanding photothermal actuation, achieving speeds up to 16.4 mm/s. In addition, the direction of motion of the actuator can be adjusted in accordance with the location of the NIR light irradiation. This study offers valuable perspectives on the application of LNSs for highvalue applications and the development of innovative photothermal-driven actuators. [ABSTRACT FROM AUTHOR]

Straw biochar was prepared by phosphoric acid activation method. Polydimethicone (PDMS) was used to modify the surface hydrophobic property of biochar. The biochar before and after PDMS modification was characterized by means of BET, FTIR and contact angle measuring instruments. This study investigated the adsorption efficiency of biochar on typical polycyclic aromatic hydrocarbons (PAHs) (phenanthrene, acenaphthe and naphthalene) in water. Under the role of PDMS modification, the maximum adsorption capacity of phenanthrene, acenaphthe and naphthalene were increased by 23%, 33% and 14%, respectively. The adsorption kinetics of PDMS modified biochar was more consistent with the quasi-second-order kinetic model, indicating that chemisorption was the main mechanism. In terms of isotherm model fitting results, the experimental results are more consistent with Freundlich model, indicating multimolecular layer adsorption. FTIR spectra showed that a new Si—O—Si bond was detected on the surface of biochar after hydrophobic modification, indicating that PDMS coating modified biochar surface, and PDMS coating increased the water contact angle of biochar surface by about 10°. PDMS hydrophobic coating can improve the hydrophobic performance of biochar, and thus improve its adsorption performance. The PDMS hydrophobic coating provides a new technique for enhancing the adsorption of PAHs from water by biochar. [ABSTRACT FROM AUTHOR]

In this work, a water-soluble (hydrophilic) polymer was used to form a hydrophobic coating on silicon substrates (Si) in a two-step process comprising (i) the transformation of the polymer into an insoluble material and (ii) the structuring of this coating at nanometric and micrometric scales to achieve the desired hydrophobic behavior. Polyvinylpyrrolidone (PVP), a water-soluble commodity polymer, was crosslinked using benzophenone and UV irradiation to produce a water-insoluble PVP coating. The nanometric scale roughness of the coating was achieved by the addition of silica nanoparticles (NPs) in the coating. The micrometric scale roughness was achieved by forming vertical pillars of PVP/NP coating. To prepare these pillars, a perforated polystyrene (PS) template was filled with a PVP/NP suspension. Micrometer scale vertical pillars of PVP/silica NPs were produced by this method, which allowed us to tune the wettability of the surface, by combining the micrometric scale roughness of the pillars to the nanometric scale roughness provided by the nanoparticles at the surface. By adjusting the various experimental parameters, a hydrophobic PVP coating was prepared with a water contact angle of 110°, resulting in an improvement of more than 80% compared to the bare flat film with an equal amount of nanoparticles. This study paves the way for the development of a more simplified experimental approach, relying on a blend of polymers containing PVP and NPs, to form the micro/nano-structured PVP pillars directly after the deposition step and the selective etching of the sacrificial major phase. [ABSTRACT FROM AUTHOR]

Despite their effectiveness in preventing icing, hydrophobic coatings possess drawbacks such as susceptibility to detachment and limited wear resistance, leading to inadequate longevity in melting ice/snow. To enhance the surface stability and durability of superhydrophobic coatings, nanoparticle/epoxy formulations were developed using three types of nanoparticles, two dispersion techniques, three application methods, and two epoxy resin introduction approaches. Testing encompassed water contact angle measurements, assessment of ice adhesion force, and determination of icing rates on asphalt concrete coated with these hydrophobic formulations. Fourier-transform infrared spectroscopy was employed to analyze the molecular structures of the coatings, while scanning electron microscopy facilitated observation of the surface morphology of the hydrophobic coatings. The findings indicated that nano-ZnO, TiO2, and SiO2 particles could be modified into hydrophobic forms using stearic acid. Application of the hydrophobic coating improved the concrete's hydrophobicity, reduced ice adhesion strength on both concrete and asphalt, and delayed the onset of icing. Furthermore, optimal dosages of stearic acid, nanoparticles, and epoxy resin were identified as crucial parameters within specific ranges to ensure the optimal hydrophobicity and durability of the coatings. [ABSTRACT FROM AUTHOR]

Although magnesium alloys have been effectively used in industry, they have weak corrosion resistance. Herein, robust Ni-thiolate coordination polymer Mg(OH)2 coatings were prepared by an oxidation-hydrolysis-coordination (OHC) strategy to make AZ31 magnesium alloy highly resistant to corrosion in 3.5 wt% NaCl solution. The OHC process includes three steps: I) oxidation of AZ31 to produce AZ31@MgO; II) hydrolysis of MgO to produce Mg(OH)2, cation exchange between Mg(OH)2 and Ni(II) to produce Mg–Ni LDH; III) coordination of Ni(OH)2 from Mg–Ni LDH by the 1,4-Benzenedithiol (BDT) ligand to produce LDH-BDT coatings. Potentiodynamic polarization, EIS, and in situ SRET in 3.5 wt% NaCl solution were used to assess the hybrid coating's anti-corrosion performance. Surprisingly, LDH-BDT coating achieves excellent corrosion inhibition performance (99.9999%) with the icorr of 1.926 × 10−10 A cm−2, which is six orders of magnitude lower than that of AZ31 substrate, this is due to the cooperative effect, such as the physical protection provided by thick LDH-BDT coatings and the hydrophobic properties of Ni(II)-BDT coordination polymers. This study provides fresh insight into the fabrication of Mg(OH)2-based coatings modified with Ni-thiolate complex to significantly improve Mg alloys' resistance to corrosion.

In order to contribute to the thriving research on bio nanocomposites for sustainable future, here we developed a cellulose nanofiber (CNF)‐based siloxane acrylic nanocomposite aiming to the application as hydrophobic coating and wood adhesive. CNF was incorporated in a copolymer matrix of poly (methyl methacrylate‐co‐butyl acrylate) [P(MMA‐co‐BA)] cross‐linked with methacrylate‐terminated siloxane (MTS). The copolymer was prepared by mini‐emulsion polymerization at a high solid content of about 57 wt%, where CNF was incorporated to the latex both by in‐situ polymerization and ex‐situ mixing process. The impact of the process of CNF incorporation and its content in the copolymer matrix were evaluated by measuring the thermal, mechanical, water repelling and adhesion properties. All the nanocomposites showed improved mechanical properties (tensile strength: upto 3.9 MPa) and wood adhesion strength (upto 1178 N) compared to the pristine copolymer. In addition, they showed significantly high water‐repelling properties on spray‐coated cotton (water contact angle: 110°–124°). Such siloxane acrylic/CNF nanocomposite has the potential as a sustainable material in the application area of hydrophobic coatings and adhesives. [ABSTRACT FROM AUTHOR]

Fish skin is a by-product of the fishing industry, which has become a significant environmental pollutant in recent years. Therefore, there is an emerging interest in developing novel technologies to utilize fish skin as a versatile raw material for the clothing and biomedical industries. Most research on finishing procedures is conducted on cattle leather, and practically very limited information on fish leather finishing is found in the literature. We have developed three functional surface finishing treatments on chromium (CL)- and vegetable (VL)- tanned salmon leather. These treatments include hydrophobic, oil repellent, and electro-conductive ones. The hydroxyl functional groups present on the surface of the leather were covalently grafted with bi-functional aliphatic small molecule, 10-undecenoylchloride (UC), by esterification reaction forming hydrophobic coating. The surface hydrophobicity was further increased via covalent binding of perfluorodecanethiol (PFDT) to the double bond end-groups of the UC-modified leather via thiol-ene click chemistry conditions. The oleophobic coating was successfully developed using synthesized fluorinated silica nanoparticles (FSN) and polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP), showing oil repellency with a contact angle of about 100° for soybean oil and n-hexadecane. The electrically conductive coating was realized by the incorporation of conjugated polymer, polyaniline (PANI), via in situ polymerization method. The treated leather exhibited surface resistivity of about 5.2 (Log (Ω/square)), much lower than untreated leather with a resistivity of 11.4 (Log (Ω/square)). [ABSTRACT FROM AUTHOR]

Steam condensation over a hybrid hydrophobic–hydrophilic surface is modeled via simplified heat transfer modelization. Filmwise condensation is assumed over the hydrophilic region. The standard film model is improved, accounting for the liquid flow rate crossing the hydrophobic–hydrophilic boundaries. A threshold for flooding occurrence is also presented. Dropwise condensation is assumed over the hydrophobic region. Compared to the heat transfer models in the literature, based on the statistical drop size distribution, a novel correlation is used for the size distribution of small droplets. The correlations of both the liquid flow rate crossing the hydrophobic–hydrophilic boundary and the size distribution of small drops are derived via Lagrangian simulations, using an in-house code previously developed and validated by the authors. The heat transfer model is validated with experimental data in the literature involving a hybrid surface, composed by alternate vertical hydrophobic–hydrophilic stripes. Then, the optimization of the hybrid surface geometry is performed in terms of hydrophobic width and hydrophilic width, with the aim of enhancing the heat flux.

Solar cells have been developed as a highly efficient source of alternative energy, collecting photons from sunlight and turning them into electricity. On the other hand, ultraviolet (UV) radiation has a substantial impact on solar cells by damaging their active layers and, as a result, lowering their efficiency. Potential solutions include the blocking of UV light (which can reduce the power output of solar cells) or converting UV photons into visible light using down-conversion optical materials. In this work, we propose a novel hydrophobic coating based on a polydimethylsiloxane (PDMS) layer with embedded red emitting Y2O3:Eu3+ (quantum yield = 78.3%) particles for UV radiation screening and conversion purposes. The favorable features of the PDMS-Y2O3:Eu3+ coating were examined using commercially available polycrystalline silicon solar cells, resulting in a notable increase in the power conversion efficiency (PCE) by ~9.23%. The chemical and UV stability of the developed coatings were assessed by exposing them to various chemical conditions and UV irradiation. It was found that the developed coating can endure tough environmental conditions, making it potentially useful as a UV-protective, water-repellent, and efficiency-enhancing coating for solar cells.

Beeswax is a bio-sourced, renewable, and even edible material that stands as a convincing option to provide paper-based food packaging with moisture resistance. Nonetheless, the difficulty of dispersing it in water limits its applicability. This work uses oxidized, negatively charged cellulose nanofibers along with glycerol to stabilize beeswax-in-water emulsions above the melting point of the wax. The synergistic effects of nanocellulose and glycerol granted the stability of the dispersion even when it cooled down, but only if the concentration of nanofibers was high enough. This required concentration (0.6–0.9 wt%) depended on the degree of oxidation of the cellulose nanofibers. Rheological hindrance was essential to prevent the buoyancy of beeswax particles, while the presence of glycerol prevented excessive aggregation. The mixtures had yield stress and showed pseudoplastic behavior at a high enough shear rate, with their apparent viscosity being positively influenced by the surface charge density of the nanofibers. When applied to packaging paper, the nanocellulose-stabilized beeswax suspensions not only enhanced its barrier properties towards liquid water (reaching a contact angle of 96°) and water vapor (<100 g m−2 d−1), but also to grease (Kit rating: 5) and airflow (>1400 Gurley s). While falling short of polyethylene-coated paper, this overall improvement, attained using only one layer of a biobased coating suspension, should be understood as a step towards replacing synthetic waxes and plastic laminates. [ABSTRACT FROM AUTHOR]

Frost accumulated on the surface of the evaporator leads to the increase of heat transfer resistance between the refrigerant and environmental medium, which reduces the system performance of cold storage and air source heat pump. To solve this problem, the surface-modified evaporator can achieve retardation of the frost formation, which greatly improves the heat exchange effect between the refrigerant and the external environment. In this paper, a novel coating sprayed on the evaporator was developed using the sol-gel method and the hydrophobicity, durability, and thermal conductivity were investigated. Moreover, a modified method of frost weight measurement under different temperatures and humidity was first proposed. The results showed that the coating has a favorable hydrophobic effect and thermal conductivity, and long service life. Under the standard experimental condition, the frost weight on the coating surface can be reduced up to 26.1 %. Additionally, the effect of coating composition ratio on its performance was further investigated. To sum up, this new coating has the potential for industrialized application.

Hydrophobic materials have promising applications. However, fluorine present in hydrophobic materials can lead to health risks and environmental pollution. This study investigated an environmentally friendly route to produce fluorine-free hydrophobic coatings with good wear resistance. Wear-resistant hydrophobic coatings were prepared by introducing different ratios of spirocyclic alkoxysilane into the epoxy resin. Characterization by Fourier transform infrared spectroscopy, water contact angle measurement, scanning electron microscope, tape adhesion test, and abrasion testing showed that the multi-methyl group and double-ring rigid skeleton structure of spirocyclic alkoxysilane can remarkably improve the hydrophobic performance and wear resistance of the epoxy resin. The modified hydrophobic coatings can withstand more than 1600 instances of controlled rubbing. Furthermore, the maximum water contact angle can reach 110° after substantial abrasion. The novelty of the work is that the authors successfully synthesized spirocyclic alkoxysilane for the first-time using corn straw ash. The prepared spirocyclic alkoxysilane was then used as a modifier to prepare hydrophobic epoxy resin coating. This approach can broaden the utilization of corn straw ash. Therefore, this method can achieve a green and low-cost preparation of wear-resistant hydrophobic coatings without the introduction of fluorine.

In this paper, a corrosion-resistant glutamic acid (Glu)-Cu-Nano-Al2O3 composite coating with both hydrophobicity and self-healing characteristics was electrodeposited on the sintered Nd-Fe-B surface. The influence of the amount of Nano-Al2O3 added in the acidic Cu2+-glutamate (Glu2−) solution on the performance of the composite coating was studied, the results show that Nano-Al2O3 inclusion can make the surface of the composite coating appear papillary particles and make the composite coating hydrophobic. By analyzing the products of the composite coating after corrosion in 3.5% NaCl solution, it is shown that the codeposition copper dihydroglutamate (CuGlu2H2) and Glu particles in the composite coating are released and dissolved in the solution with pH = 6.5 after copper corrosion, and then complexed with Cu2+produced by corrosion to form an insoluble copper glutamate (CuGlu) passive film, which was deposited on the corroded coating to achieve self-repairing function and prevent further corrosion. The hydrophobicity and self-repairing function of the composite coating ensure that the sintered Nd-Fe-B has excellent corrosion resistance.

Copyright of Journal of Materials Science & Engineering (1673-2812) is the property of Journal of Materials Science & Engineering 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 New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials 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.)

Wind turbines operating in cold regions are prone to blade icing, which seriously affects their aerodynamic characteristics and safety performance. Coatings are one of the effective solutions to the icing problem on wind turbine blades. In this study, MoS2/ZnO/PDMS superhydrophobic nano-anti-icing coatings were prepared using the hydrothermal method and the liquid phase method. SEM revealed that the MoS2/ZnO coating was a typical superhydrophobic nanostructure with an ultra-thin sheet-like morphology of clusters and a hilly nano-rough structure, with contact angles (CA) of 152.1° and 4.7° with water droplets and the sliding angle (SA), respectively. The MoS2/ZnO/PDMS coating had an adhesion strength to ice of 78 kPa, which was 60.2% lower than an uncoated surface. The icing effects of the NACA0018 airfoil blade model with or without MoS2/ZnO coatings were studied at different ambient temperatures and wind speeds using the icing wind tunnel test. The results showed that, compared to uncoated blades, the level of icing was lower on the blade airfoil surface that was coated with MoS2/ZnO. At 10 m/s and −10 °C, the icing thickness and icing area of the leading edge of the blade airfoil were 13.7% and 28.3% lower, respectively. This study provides a valuable reference for the development of anti-icing coatings for wind turbine blades. [ABSTRACT FROM AUTHOR]

Abstract A Zn‐based coating with durable hydrophobicity and good corrosion resistance was formed on a mild steel substrate, which involves electroplating Zn from a non‐aqueous electrolyte, followed by passivation in an oleic acid (OA) solution. The electrodeposited Zn coatings were porous, which facilitated the formation of a chemical conversion layer of Zn oleate (ZO) during OA passivation. The Zn coating after passivation had a two‐layer structure, which included an outer layer of ZO with a thickness of ∼26 μm and an inner layer of Zn with a thickness of ∼6 μm. The outer layer ZO is a type of metal soap with a smooth surface and durable hydrophobicity, such that water droplets can easily slip off its surface. Corrosion testing and electrochemical measurements in 3.5 wt.% NaCl aqueous solution indicate that the Zn coating after OA passivation exhibits outstanding anti‐corrosion properties compared with those exhibited by pure Zn coating. The corrosion products and mechanism of the two‐layer coating were explored. This study shows that smooth metal oleate coatings can provide hydrophobicity and corrosion resistance simultaneously to mild steel substrates.

[Display omitted] • Hydrophobic coating with dew suppression shows 50 ± 13 % reduction in soiling loss. • Hydrophobic coating without dew suppression shows 31 ± 15 % reduction in soiling loss. • Coating decreases the deposition of 10 to 30 μm particles by 60.0 ± 8.1% (mass) • Multiple dew events cause more milli-scale non-uniformity on the glass. The deposition of particulate matter (PM) on PV surfaces reduces energy generation, which results in huge losses to the PV industry. Hydrophobic coatings are known to reduce PM deposition on PV surfaces. Covering panels during the night is expected to reduce the PM deposition as well as suppress the dew formation on the surface. The objective of the present study is to compare the soiling on the hydrophobic coating with and without dew suppression. Uncoated and hydrophobic coated slides were kept for PM deposition in a 70-day field study. The dew formation was suppressed on some of the uncoated and coated slides by covering them from sunset to sunrise. The results show that the % reduction in soiling of coated slides under dew suppression is higher (50 ± 13%) compared to the coated slides without dew suppression (31 ± 15%) (statistically different; two-tailed p-value < 0.05). In addition, the particle size analysis using optical microscopy shows that the hydrophobic coating (under dew suppression) reduces the particles deposition by 60.0 ± 8.1% (mainly 10 to 30 μm range) compared to the uncoated slides (under dew suppression) over the entire sampling period. However, the dust potency (soiling loss per unit deposited mass loading) for uncoated and coated samples is found to be statistically similar (5 to 6 % g−1 m2; two-tailed p-values > 0.05). Overall, the present study advances the understanding of the impact of dew on hydrophobic coating, thereby adding to the existing knowledge of soiling mitigation approaches for solar PV industries. [ABSTRACT FROM AUTHOR]

Cellulose-based materials represent a renewable, biodegradable, and environmentally friendly alternative to plastic from fossil resources. Nanopaper is a strong and lightweight material formed from cellulose nanofibrils (CNFs). Paper and nanopaper have been considered as excellent alternatives to plastics for use in agriculture and for packaging applications. However, common for both paper and nanopaper is their hydrophilic character, and consequently, poor water-resistance properties. ORMOCER®s are a class of inorganic–organic polymers with excellent barrier and protective properties used for a range of coating applications. Here we present ORMOCER®-coated paper and nanopaper. The coated papers and nanopapers are characterized, both in terms of their morphology, hydrophobicity, and mechanical properties. We demonstrate that the pressure used during the pressing and drying of paper and nanopaper influence their tear and tensile—properties, and that the morphology of the coated nanopaper differs significantly from that of the coated paper. While the ORMOCER® was impregnated within the porous network of the paper, a well-defined two-layered morphology was obtained with the coated nanopaper. Further, the biodegradability of the nanopaper with and without coating was assessed. The degradation study demonstrated that both the pressure used during the pressing and drying of the nanopaper, and the composition of the ORMOCER®, influenced the rate of degradation. Taken together, ORMOCER®-coated paper and nanopaper are promising for the preparation of materials that are both water-resistant, renewable, and biodegradable. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophobic surface treated HKUST-1 (HHK-x) is manufactured. • High stability in continuous exposure to moisture containing air condition. • Sacrificial hydrolysis reaction of hydrophobic layer protects the structure. • Water sorption resistance is enhanced by 50.2 % compared to pristine HKUST-1. Imparting water resistance is important for structures which is vulnerable to moisture to maintain the performance. In this study, octadecyltrimethoxysilane (ODTMS), which forms a hydrophobic surface through polymerization on the surface of the material, was used to enhance the hydrophobicity of HKUST-1 (HHK-x). This self-assembled structure reacts as sacrificial barrier to continuously penetrating H 2 O molecules and this effect is evaluated with detection of O–H peak (3323 cm−1) in FT-IR spectra. The gas adsorption performance is conducted with CO 2 gas and the adsorption amount was reduced by 20 % (from 5.77 to 4.62 mmol/g at 25 °C, 1 bar) compared with the pristine HKUST-1 following the trend of specific surface area. However, water adsorption amount was reduced by 50.2 %, which is 2.5 times higher than the decrease in CO 2 adsorption capacity. In addition, when the N 2 adsorption and cycle adsorption performances were compared after exposing the sample to air for five days, it was confirmed that HHK-40 maintained its microporous structure and stable performance. The manufactured materials exhibited higher durability in a cyclic vapor sorption test depending on the loading amount of ODTMS and exhibits different tendency depending on the rate of humidity. These results experimentally indicate that accessible self-assembly process of ODTMS on water-vulnerable materials to be sustainable and stable in humid air conditions. [ABSTRACT FROM AUTHOR]

The development of hydrophobic surfaces is an important factor for clean energy production from solar arrays, enabling their operation at the highest possible efficiencies for the longest possible time, without the need for physical intervention. This work reports the development of hydrophobic Y 2 O 3 thin films on a range of transparent glass substrates. The growth of the Y 2 O 3 films from the mono-hydrate yttrium (III) complex of 1,3-diphenyl-1,3-propanedione [Y(dbm) 3 (H 2 O)] is studied using the aerosol-assisted chemical vapor deposition (AACVD) technique. The qualitative evaluation of the deposited films and their hydrophobicity is assessed using several materials characterization techniques, such as scanning electron microscopy, grazing incident X-ray diffraction, Fourier-transform infrared, X-Ray photoelectron spectroscopy, in addition to a surface free energy and water contact angle measurements. This work demonstrates experimentally a relationship between the Y 2 O 3 wettability and its physico-chemical characteristics in terms of surface energy, chemical composition, and morphology which is controlled by the type of glass support used. The water contact angle of the hydrophobic Y 2 O 3 coating grown on the F-doped tin oxide glass reached 128°; currently the first deposited on transparent glass. This film exhibits the highest WCA reported up to date without the need for performing post-reaction surface treatment processes. The hydrophobic nature of the transparent Y 2 O 3 films marks a significant leap forward in the field of anti-soiling coatings suitable for photovoltaic technology. [Display omitted] • New AACVD protocol for synthesis of hydrophobic Y 2 O 3 coating was developed. • The Y 2 O 3 films grown on the glass substrates were hydrophobic and exhibited WCAs of 128, 120 and 104°. • Strong substrate growth control in the AACVD process of the Y 2 O 3 was demonstrated. • Clear relationship between the Y 2 O 3 wettability, its surface chemical composition and physico-chemical properties is provided. [ABSTRACT FROM AUTHOR]

Currently, an increasing number of studies focus on the applications of hydrophobic surfaces for underwater drag reduction. However, the drag reduction mechanisms of hydrophobic coatings with controllable wettability still lack systematic understanding. Herein, nano-SiO 2 composite coatings with different contact angles were fabricated using air spraying techniques. The relationship between the hydrophobicity of these coatings and their drag reduction performance under different Reynolds numbers was further investigated. The results showed that the uniformed distributed air layer and low depinning force significantly contributed to drag reduction performance. The coating with a contact angle of 140° achieved a maximum reduction rate of 58 % at a Reynolds number of 750. However, the coatings with contact angles of 150° and 155° exhibited diminished drag reduction effects due to the uneven distribution of the air film. This study highlighted that the hydrophobicity of the coatings and the uniform microstructures are essential for sustaining effective drag reduction performance. • Different hydrophobic coatings were used for drag reduction experiments. • The surface of the hydrophobic coating exhibited a low depinning force. • Highly hydrophobic coating exhibited the best drag reduction performance. • The impact of air film distribution on drag reduction was clarified. [ABSTRACT FROM AUTHOR]

A series of polymethylhydrosiloxane modifying acrylic resins (PSi-AR resins) have been designed and synthesized. Their properties have been studied by varying the relative content of the two components. Firstly, polymethylhydrosiloxane (PHMS) was modified with divinylbenzene (DVB) via electrophilic addition to endow it with the reactive functional groups. Then the modified PHMS (D-PHMS) was blended with acrylic monomers, initiator, and the mixed solvent, and the PSi-AR resins were obtained via solution polymerization. The structure and the thermodynamic properties of the resins, and the interface character, mechanical and anticorrosion properties of the corresponding coatings were studied systematically. In particular, the self-stratification properties of the PSi-AR resins have been studied in detail. Since the D-PHMS component tended to float on the top layer of the coating, the surface of the coating showed hydrophobic properties, with which the contact angle of the coatings was >100° and increased with the content of D-PHMS. With excellent mechanical and anticorrosion properties, the coatings demonstrate excellent performance, which can be potentially employed in paints for metal corrosion protection. • Knitting a polymer with carbon bonds to synthesize a self-stratification resin, stable in a wide pH range. • The cured self-stratifying coatings exhibit hydrophobicity, heat resistance, and corrosion resistance. • The characteristic of low surface tension endows the coating with excellent anti-fouling properties. [ABSTRACT FROM AUTHOR]

Biobased packaging materials derived from carbon-neutral feedstocks are sustainable alternatives to conventional fossil-based polymers. In this study, a method was developed to prepare paper-sheets derived from Miscanthus × giganteus cellulose fibers for potential food contact applications. The papers were hydrophobized with modified lignin from Miscanthus × giganteus biomass and commercial Kraft alkali lignin through hydroxyethylation with ethylene carbonate, followed by esterification with propionic acid. The esterified lignin (10 % w /w) and cellulose acetate (5 % w/w, based on lignin content) were dissolved in acetone and applied as a coating on the miscanthus paper sheets. The esterified lignins were characterized using FTIR, NMR, DSC, TGA, and elemental analyses. The uncoated and coated paper-sheets had contact angle values 52.4° and >130°, respectively, indicating an increased surface hydrophobicity of the coated paper samples. The water vapor transmission rate decreased significantly from 213.7 (uncoated paper-sheet) to 63.3 g/m2.d (coated paper-sheet). The tensile strength of the coated paper (64.6 MPa) was higher than the uncoated counterpart (57.1 MPa). Results from this study suggest that the esterified lignin coated miscanthus paper is a promising hydrophobic food packaging material alternative to conventional fossil-based thermoplastics. [Display omitted] • Lignin from miscanthus biomass was hydroxyethylated followed by esterification. • Extracted cellulose fibers from miscanthus were used to fabricate paper-sheet. • Esterified lignin-cellulose acetate coating was applied on the paper-sheet. • Coated paper-sheet exhibited an excellent hydrophobicity (contact angle ˃134°). • Coating significantly increased tensile strength and moisture barrier of the paper-sheet. [ABSTRACT FROM AUTHOR]

Rare earth oxides (REOs) and metals as an important class of materials have generated global interest in modern technology. Here, eight REOs (R 2 O 3 , R = Yb, Er, Sm, Eu, Y, Gd, Dy, and Ce) are identified those are mostly used in diverse chemical and industrial sectors. In this concise review the applications of these REOs in corrosion protection, thermal barrier coating, hydrophobic coating, catalytic reactions, refrigeration, photoactivity, environmental, and tribological sector are briefly summarized, which are sparsely documented in the existing literature review. In what follows, recently published relevant literature is systematically evaluated and key insights are addressed. The use of REOs as nonstoichiometric compounds or as doping agents to enhance the system performance of specific applications is commendable. Related lab-scale studies, therefore, will invoke the potential exploitation of individual or blended REOs for large-scale commercialization. However, phase transformation and high energy consumption in the thermal coating, multi-step fabrication of hydrophobic coating, the building of aromatic pollutants in catalysis, magnetic entropy shift in refrigeration, and photo corrosion are some of the inherent hindrances of these oxides. These issues warrant prompt actions from the scientific community to deliver cost-effective, efficient, and environmentally sustainable applications. Regardless, this review is expected to provide critical insights into REOs for contrasting industrial applications and encourage interested researchers to dig deeper in finding the best strategic solutions to counter prevalent challenges. [Display omitted] • Catalysis: REOs enhanced photocatalytic dye degradation activity. • Tribological: REOs enhance wear properties of hybrid composites. • Coating: REOs are potential for thermal barrier & corrosion-resistance coating. • Sustainability: REOs' contribution to recycling materials and water treatment. • Prospect: REOs possess great potential in eco-friendly applications. [ABSTRACT FROM AUTHOR]