Fabrication of superhydrophobic transparent cyclic olefin copolymer (COC)‐SiO₂ nanocomposite surfaces

Abstract

A superhydrophobic cyclic olefin copolymer (COC) nanocomposite coating was produced with a very simple and easy method. Self-cleaning superhydrophobic COC surfaces were obtained by only adding surface hydrophobized SiO 2 nanoparticles by dip coating method. The influence of concentration of SiO 2 and the coating temperatures on the wettability of the surfaces were investigated. The surface wettability of the coatings was examined with the contact angle measurements and the surface roughness and morphology were analyzed by using atomic force microscope and scanning electron microscopy analysis. Surfaces with certain amounts of COC and SiO 2 showed superhydrophobic character with high water contact angle of 169 0. Also, the obtained superhydrophobic surfaces show superior water repellent, high transparency, and self-cleaning characteristics.

Investigation of Superhydrophobic and Anticorrosive Epoxy Films with Al2O3 Nanoparticles on Different Surfaces

“…This situation showed that there was a transition behavior from the Wenzel model to the Cassie–Baxter model after from 1% Al 2 O 3 concentration. A similar transition behavior was given by several authors in the literature. ,, It was determined that the hysteresis values on glass, galvanized steel, and skin-passed galvanized steel surfaces were 9.9, 6.3, and 7.2 at 8% Al 2 O 3 concentration, respectively.…”

“…CAH was calculated by taking the difference between the advancing and receding contact angles (CAH = θ a – θ r ) and an important parameter to understand the movement of liquid droplets on solid surfaces. The Wenzel and Cassie–Baxter models are two classical models generally used for describing the wetting properties of superhydrophobic surfaces. ,,,,− The equilibrium contact angle generally increases with increasing nanoparticle concentration due to the increasing surface roughness, but CAH behaves differently and oppositely in the two models. When the drop generally sticks strongly to the surface and CAH is large, it is defined as Wenzel mode.…”

“…Self-cleaning performance is an indispensable property of superhydrophobic surfaces. ,,,, Figure shows the self-cleaning process by dripping water with syringe on the surface of three different substrates coated with epoxy containing 5% Al 2 O 3 concentration. The water was dropped on the surface slowly.…”

“…The first procedure is to produce hierarchical micro–nano roughness on the hydrophobic surfaces, and the other one is to make modifications to the rough surface to lower the surface free energy using silicones, fluorocarbons etc. − In recent years, the addition of inorganic metal oxide nanoparticles like SiO 2 , TiO 2 , Al 2 O 3 etc. to polymeric matrix is an easy and practical method to create multi-scale roughness to enhance the superhydrophobicity. − Alumina (Al 2 O 3 ) nanoparticles are one of the important materials that are utilized for creating superhydrophobic surfaces. ,− Barron et al used unmodified and chemically modified alumina nanoparticles. They used the carboxylic acids for modification on nanoparticles and investigated the effects of carbon chain lengths and branching factors on the surface modification of nanoparticles.…”

Preparation and Application of Fluorine-Free Finishing Agent with Excellent Water Repellency for Cotton Fabric

“…Meanwhile, the micro- and nanostructures formed by physical deposition are easily worn off by mechanical force, causing the loss of hydrophobic properties [ 26 ]. Additionally, although many techniques for constructing bionic rough surfaces have been developed, such as sol-gel [ 27 , 28 ], etching [ 29 , 30 ], self-assembly [ 31 , 32 ], deposition [ 33 , 34 , 35 ] and solution impregnation method [ 36 , 37 ], these methods often require harsh preparation conditions, special processing equipment and tedious operational steps. As a result, they are not suitable for industrialization or application in the water repellent finishing of cotton fabric [ 20 , 21 ].…”