Durable superhydrophobic surfaces
With the development of smart electronic devices, the importance of surface-protective coatings is rapidly increasing. Superhydrophobic surfaces are promising protective coatings that exhibit potential for anti-wetting, self-cleaning, and antibacterial applications. However, their poor mechanical durability makes their practical application difficult. Additionally, rough surface geometries induce incident light scattering, thereby reducing the transparency and limiting their optical applications. A new study describes semi-transparent superhydrophobic surfaces with improved mechanical strength and thermal stability obtained through simple spray coating.
High-water repellency
The researchers mixed reactive polydimethylsiloxane (PDMS) as a binder with low surface free energy and high thermal resistance with fluorinated silica nanoparticles. PDMS polymers were functionalised to improve their hydrophobicity and adhesion properties through hydrosilylation with acrylate monomers. As a result, the superhydrophobic surfaces had a high-water repellency of above 160° and transparency of approximately 60 % at a wavelength of 550 nm. The coated surfaces exhibited an outstanding pencil hardness of 5H. After heat treatment at 400 °C, the hardness increased to 6H while maintaining superhydrophobicity. Additionally, various contaminants were easily removed with water spraying.
The study has been published in Progress in Organic Coatings, Volume 179, June 2023.
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