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In this work, a translucent superhydrophobic coating was fabricated by a simple spray-coating technique using fluorine-free and easily available materials, viz , the hybrids of PDMS and PMMA in THF solution, without any pre-/post-treatment. The combination of the microscale roughness of the sprayed-PMMA, along with the low surface energy PDMS, has contributed to the observed superhydrophobicity. The as-prepared PDMS/PMMA@superhydrophobic surface has displayed a water contact angle of 157.5° and sliding angle of 2.8°. Furthermore, the liquids with various surface tension, ranging from water to various organic liquids, displayed nearly spherical shapes on the superhydrophobic substrate. In addition, this coating has also shown significant stability against sand abrasion and water droplet impact, and was able to maintain its superhydrophobicity after being soaked in strong acid and salkali solutions. Moreover, the superhydrophobic coating was found to be translucent with good visibility of the characters through the coated glass substrate. The transformation from a superhydrophobic state to superhydrophilic state can be realized via a hot-press process, and such a facile technique can be easily applied to potential applications in surface patterning. Additionally, the super-antiwetting surface has been demonstrated for applications in highly efficient oil-water emulsion separation, anti-fouling, and self-cleaning. [ABSTRACT FROM AUTHOR]

The superhydrophobic TiO 2 coating was fabricated on cotton fabric through a facile one step hot-pressing process after being dipped in n-octyltriethoxysilane and Ti-containing precursor mixed solution. The as-prepared fabric exhibited robust superhydrophobic with a water contact angle higher than 150° and realized an optimized UV protective factor of 45. The as-constructed superhydrophobic fabric was able to withstand more than 800 cycles of abrasion. Moreover, there was not apparent decrease of superhydrophobicity after 10 cycles of accelerated machine wash and the as-constructed fabric also showed a strong ability to resist acidic and alkaline solutions. Finally, the potential applications of such value-added fabrics self-cleaning, anti-fouling, and water-oil separation were investigated as well. The results demonstrated that the combination of n-octyltriethoxysilane and Ti-containing precursor coating endowed the pristine fabrics with excellent self-cleaning for dusts and anti-fouling for methylene blue dye, as well as excellent separation efficiency for the oil-water mixtures. This facile synthesis stragegy can also be extended to quickly construct multifunctional fabrics with speical wettability in a large scale and utilized in some promising fields. [ABSTRACT FROM AUTHOR]

Despite the existing effort, fabricating superhydrophobic substrate through an environmental friendly approach remains a great challenge. In the current work, we present a simple approach to fabricate robust superhydrophobic surfaces on different kinds of substrates using phase-separation method. This method uses polydimethylsiloxane (PDMS) as the binder, tetrahydrofuran (THF) as the solvent, and water as nonsolvent. The emulsion prepared under optimum proportion of THF and water was stable and showed no obvious change even after being stored for 6 weeks. The coated substrates exhibit superhydrophobic property with a water contact angle (CA) larger than 155.0°. Moreover, because the solution is rich of water, and the surface modification condition is mild, the PDMS coating enjoys a high degree of transparency. Finally, superhydrophobic cotton and sponge were successfully demonstrated for oil-water and oil-in-water emulsion separation. This facile synthesis method has a potential for a broad range of applications in large-scale fabrication of superhydrophobic surfaces and filtration membranes. [ABSTRACT FROM AUTHOR]

It remains a great challenge to prepare multi-functional fabrics using a low-cost and scalable method with fluorine-free materials. In this paper, we report a new procedure for producing fluorine-free super hydrophobic cotton fabrics, via a simple dip-coating process. Firstly, a polydimethylsiloxane (PDMS) adhesive layer is deposited onto the cotton substrate, followed by the subsequent deposition of ZnO nanoparticles to enhance the surface roughness through an oil bath process. Finally, a second PDMS dip-coating is applied to construct a multi-layered PDMS-ZnO-PDMS composite coating on the cotton fabrics. The multi-layer coated samples display superhydrophobic properties, with a water contact angle (CA) exceeding 160°. Additionally, the new PDMS-ZnO-PDMS@cotton fabric exhibits excellent multi-functions, including UV-blocking, self-cleaning and oil-water separation. The prepared superhydrophobic fabric can withstand a large number of abrasion cycles and 20 cycles of accelerated washing without obvious decline in the water contact angle. This facile preparation method is of low-cost, environmentally friendly, and suitable for large-scale production of a series of specialty fabrics including sports clothing. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The superhydrophobic finishing strategy is environmentally-friendly and fluorine-free. • This system is suitable for multiple biomass fabrics by enzymatic hydrolysis etching. • The construction do no harm to colors and patterns of dyed fabrics. • This method can construct multifunctional fabrics for efficient self-cleaning and versatile oil-water separation. Abstract Superhydrophobic silk fabrics were prepared using an environmentally friendly enzyme-etching approach, followed by the modification with methyltrichlorosilane (MTCS) via a simple thermal chemical vapor deposition (CVD) process at 70 °C. The effects of the concentration, treatment time and temperature of enzyme on the etched surface properties were discussed. The composite superhydrophobic silk fabrics demonstrated excellent self-cleaning ability, relatively unscathed effecting their intrinsic properties such as the luster, softness, color and style of the fabrics. Furthermore, these treated fabrics demonstrated excellent mechanical durability after silane-treatment as evidenced by the cyclic abrasion and laundering tests. The composite superhydrophobic cotton fabrics have also demonstrated a high efficiency in oil-water separation. The facile technology via enzymatic hydrolysis to etch the substrate possesses extensive potential applications on various other cellulose-based substrates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effective and low-consumption foam finishing strategy for multifunctional fabrics. • Superhydrophobic coating with micro/nano structures is rationally constructed. • Robust PDMS-based coating exhibits excellent mechanical properties and durability. • Rational PDMS-based coating strategy realizes on-demand special wettability. • Wetting micropattern and directional water transportation activity is demonstrated. The technologies of superhydrophobic finishing normally involve harmful reagents such as fluorine-containing materials and organic solvents. Non-toxic, environmentally friendly, and large-scale applicable preparation methods for superhydrophobic finishing remain a considerable challenge towards practical applications. In this paper, we proposed a superhydrophobic foam finishing method with a low liquid-carrying rate. This finishing solution is totally water-based without the use of any organic solvents or fluorine-containing materials. Based on the characteristics of low liquid-carrying rate, this method can save nearly 60% of the solution consumption. In addition, multifunctional superhydrophobic fabrics, such as hydrophobic patterns and Janus fabrics, can be fabricated by this foam finishing method. Excellent properties such as superhydrophobicity, anti-fouling, and directional water transportation could be achieved by controlling the amount of superhydrophobic foams. Compared with other finishing technologies, the foam finishing method has the advantages of being facile, rapid in preparation, environmentally friendly, and applicable for large-scale production. This technology could be applied on various substrates and achieve rapid preparation for superhydrophobic surface, Janus surface, and double-sided heterochromatic superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]