Jo Jul 9, 2024

Superhydrophobic materials find their applications in self-cleaning, resistance reduction, corrosion protection, and anti-fogging due to their unique hydrophobicity. Lotus, a natural superhydrophobic material (SHP), has a contact angle (CA) of 162° because it has teat-like microstructures with a diameter of 5-9㎛ and nanostructures with a diameter of 124nm. One of the interesting applications of SHP materials is their self-cleaning ability to prevent and remove contamination of material surface by itself.

Superhydrophobic materials can be prepared by various methods, such as physical and chemical decomposition, chemical etching, anode oxidation, laser etching, chemical vapor deposition, sol-gel method, etc. The sol-gel method is a promising method for large-scale applications (metal, glass, ceramics and plastics), which can improve the mechanical durability of superhydrophobic materials and reduce fabrication cost.

Hollow ash is 10-20% in fly ash, a waste produced by coal-fired power plants. Hollow ash has excellent thermal insulation properties due to its porosity in the particles, so it is widely used as an insulating material.

Kim Jong Ho, a researcher at the Faculty of Chemistry, has formed a thermal barrier layer by using a composite solution of MMA-BA co-polymers and hollow ash, and investigated the functional coatings with high thermal insulation efficiency, self-cleaning ability and anticontamination performance. Based on the literature, he prepared mixed solutions of MMA-BA co-polymers and silica sol by using methyl methacrylate, butyl acrylate, methacrylate-β-hydroxyethyl ester and o-xylene. To maximize the thermal barrier properties and superhydrophobicity of the coatings, he carefully studied the effects of various factors such as the ratio of raw materials, coating thickness, and morphology.

Thermal characterization of the prepared films showed that the thermal insulation effect of the films was enhanced when hollow ash was added to the MMA-BA co-polymers solution.