Fabrication of Superhydrophobic Coating Based on Waterborne Silicone-Modified Polyurethane Dispersion and Silica Nanoparticles

Abstract

In this work, eco-friendly superhydrophobic coatings were prepared by dispersing hydrophobic silica nanoparticles and a waterborne silicone-modified polyurethane dispersion into an ethanol solution, which was free of fluorine and volatile toxic solvents. The effects of the silica content on the hydrophobicity and scratch resistance of the hydrophobic surfaces were investigated by WCA measurements and a sandpaper abrasion test, respectively. The experimental results indicated that when the silica content exceeded 30% by mass, the silica/silicone-modified polyurethane coatings had superhydrophobicity. Meanwhile, the superhydrophobic coatings with a silica content of 30% by mass simultaneously had the optimal mechanical stability. We studied the morphology and roughness of the hydrophobic surfaces with different silica content and attempted to briefly explain the influence mechanism of silica content. Furthermore, anti-icing and oil–water separation experiments were carried out on the superhydrophobic coatings, which exhibited good anti-icing performance and high separation efficiency. The eco-friendly superhydrophobic coating is expected to be applied in the fields of oil–water separation, anti-icing, and self-cleaning, etc.

Toward mechanically robust self-healing polyurethanes using dynamics chemistry

“…For example, Namita et al 141 added silane to the PU to enhance the adhesion between the coating and the metal surface. Liu et al 142 added silica and organosilicon to make the PU composite material hydrophobic. When the proportion of silica is 30 wt%, the PU composite coating has the best mechanical stability.…”

Study of a Novel Fluorine-Containing Polyether Waterborne Polyurethane with POSS as a Cross-Linking Agent

“…It was because that the fluorine-based soft chain in the FWPU could greatly reduce the surface energy and achieve the hydrophobic effect of the composite films. It also effected on the silicon element of the POSS structure to enhance the hydrophobicity of the FWPU [36,37].…”

No‐organic solvent, no‐fluorinated waterborne superhydrophobic coatings based on SiO2 and IBTS

“…14,15 However, there are bottlenecks in real applications such as difficult operation, high production costs and the need for organic solvents and organic fluorine, which harm the ecosystem and human health. Volatile solvents such as acetone, 16,17 alcohols, 18 ether 19 and aromatic hydrocarbons 20 are commonly used to prepare superhydrophobic coatings, which eventually evaporate into the environment and cause pollution and safety challenges. Low surface energy substances such as organic silane, organic fluorine, 21 and modified cellulose are usually used to endow coatings with hydrophobicity and rough structure.…”

“…Two main solutions are used in the current study:One is to perform surface roughness treatment on water-based coatings and then spray them again or use low surface energy substances for coatings 25 ; The second method is to dissolve low surface energy substances in organic solvents, such as acetone, methyl ether, and then mix them with water-based coatings. 18 The above research methods have the drawbacks of complex preparation and high volatile organic compounds, and the hydrophobic durability of the coating is also not ideal. The one-step spraying method used in this study avoids the above defective preparation methods, reduces the difficulty of operation during application, and protects the health of construction workers.…”

“…In addition, the surface energy of hydrophobic particles is so high that it is difficult to stabilize them in aqueous emulsions. Two main solutions are used in the current study:One is to perform surface roughness treatment on water‐based coatings and then spray them again or use low surface energy substances for coatings 25 ; The second method is to dissolve low surface energy substances in organic solvents, such as acetone, methyl ether, and then mix them with water‐based coatings 18 . The above research methods have the drawbacks of complex preparation and high volatile organic compounds, and the hydrophobic durability of the coating is also not ideal.…”