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A super‐robust and self‐repairing superhydrophobic (SRS) coating is prepared on foamed concrete via a facile and low‐cost method using hydrophobic silica nanoparticles as building blocks connected by silicone sealant and epoxy resin for constructing micro‐/nanostructures. The surface wettability, morphology, and chemical composition are tested by a contact angle (CA) goniometer, scanning electron microscope, and Fourier‐transform infrared spectrometer, respectively. All the as‐prepared SRS coatings exhibit satisfied superhydrophobicity with the hydrostatic CA of about 160° and the sliding angle (SA) of about 1.7°. The results show that the SRS coating has good self‐repairing performance. For testing its mechanical stability, the superhydrophobic foam concrete is tested by 200 g (2.83 kPa) weight, sanded by 800 mesh sandpaper, which can be worn for 150 cycles (21 m), better than the reported mechanical performance. In addition, the superhydrophobicity can recover by heating at 100 °C for half an hour. The preparation method of the coating is simple, low cost, and excellent in mechanical performance, which provides the possibility for large‐scale industrial applications in the construction field. [ABSTRACT FROM AUTHOR]

In this paper, we present a convenient approach to prepare hierarchical structured superhydrophobic coatings with tunable adhesion force, composed of micro-size glass beads, nano-size SiO 2 particles and epoxy resin. Surfaces of two types with different roughness were fabricated, one type is only with single-scale roughness demonstrating lotus effect with low sliding angle, the other type is hierarchically micro-nano-structured roughness exhibiting petal effect with high adhesion force. The surface roughness is pivotal for controlling the wetting behavior and regulating the contact angle including the contact angle hysteresis. Varying the density of micro-size glass beads could adjust the roughness of the surface, which means the adhesion force of the prepared surface could be easily controlled based on the proposed method. Through variation of glass beads' amount, the surface could be designed to pin the water droplet with different adhesion force when the surface turned upside down. The surface wettability, surface morphology, adhesion force of the prepared samples are investigated and mechanism of the Cassie-to-Wenzel state transition are discussed in detail. Furthermore, the convenient method provides a possibility for controlling surface morphology, composition and corresponding surface adhesion which could be applied to various substrates such as tile, wood, steel and fabric. [ABSTRACT FROM AUTHOR]

A highly transparent and stable superhydrophobic surface was prepared on substrates of different types including tile, concrete, wood, and ferroalloy via a facile and low-cost method using hydrophobic silica nanoparticles as building blocks for construction of micro/nano-structures and neutral silicone sealant as binder. The surface wettability, morphology, topography, and transmittance was characterized by means of contact angle measurement, scanning electron microscope, atomic force microscope, and ultraviolet-visible spectrophotometer respectively. All the as-prepared SiO 2 /Silicone composite coatings exhibited well water-repellency with a static water contact angle above 150° and a sliding angle below 10°. Besides, a highest average transmittance of 88.7% of the superhydrophobic coatings was obtained. The results of the performance testing showed that the superhydrophobic coatings possess good mechanical resistance to water drops, as well as excellent chemical/thermal stability and UV durability. Moreover, the method to fabricate superhydrophbic coatings on various substrates is facile and cost-effective, which provides a possibility of large-scale industrial applications. • Superhydrophobic transparent coating prepared by nano-silica and silicone sealant. • This one-step facile route could be extended to different types of substrates. • The developed coatings exhibits good mechanical/chemical/thermal/UV resistance. [ABSTRACT FROM AUTHOR]