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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]

Mussel‐inspired polycatecholamine coatings and films have proven to be versatile materials for surface modification. However, the progress of chemically modified coatings with tailored properties has been slow due to the lack of definitive evidence of their polymeric structure. Polycatecholamines form aggregates during polymerization, and their formation mechanism has been a subject of debate owing to their insolubility in traditional molecular solvents. Exploiting the capability of ionic liquids (ILs) to exhibit strong electrostatic interactions, herein, the first solution‐phase polymerization approach is reported to achieve polymerization of four catecholamines – dopamine (DA), norepinephrine (NE), L‐3,4‐dihydroxyphenylalanine (L‐DOPA), and adrenaline (AD). Kinetic control over the polymerization process in the solution phase enabled it to follow the process with 1H NMR spectroscopy, revealing the formation of structural features of resulting complex heterogeneous and soluble polymers. The polymers are both covalent and associative in nature. Solution phase polymerization prevented the formation of large aggregates in the solution, thus facilitating the formation of coatings that are ultra‐smooth and have root mean square roughness of the order of sub‐nm to nm scale. [ABSTRACT FROM AUTHOR]

To prepare durable superhydrophobic coatings with low-cost is of great importance for its practical application. How to improve the mechanical endurance by a facile method is rarely mentioned in reports. Achieving thicker coating with multi-layer micro-nano structures is critical for obtaining the robust superhydrophobic coating due to the high abrasion resistance to mechanical damage. Herein, a superhydrophobic coating with a multi-layer self-similar structure was fabricated by a facile blending and spraying method. Epoxy resin, neutral silicone glue, polysiloxane and nano-SiO 2 are the main composition of the ESPS coating which are important for the multi-layer micro-nano structure construction and adhesion stability between the coating and the substrate. The water contact angle (WCA) and sliding angle (SA) of the ESPS coating were 162.5 ± 0.5° and 4.6 ± 0.4°, respectively. Notably, the ESPS coating with four layers can be abraded with 1500-grid sandpaper under the load of 400 Pa for 24 m. In addition, the prepared samples were put in an outdoor environment for 180 days and exhibited excellent durability and stability. These outstanding properties could be attributed to the hierarchical self-similar structure of the composited coating and the good resistance and adhesion stability provided by polysiloxane. Additionally, the ESPS coating could restore its superhydrophobic characteristic by self-healing realized by the neutral silicone glue in the composition. The good stability and operability of the ESPS coating make it applicable to a wide range of applications. • A multi-layer self-similar superhydrophobic coating was prepared by a simple, cheap and harmless method. • The mechanical durability of the superhydrophobic coating can be improved by increasing the longitudinal thickness. • Plasticizer was used to improve the ductility of epoxy resin which is important for its superhydrophobic performance. • Self-healing property of the coating could be realized by the neutral silicone glue in the composite. [ABSTRACT FROM AUTHOR]