Characteristics and self-cleaning effect of the transparent super-hydrophobic film having nanofibers array structures

• Published in: Applied surface science 2010-09, Vol.256 (22), p.6729-6735
• Main Authors: Lee, Kyungjun, Lyu, Sungnam, Lee, Sangmin, Kim, Youn Sang, Hwang, Woonbong
• Format: Article
• Language: English
• Subjects: Anodic aluminum oxide (AAO); Anodizing; Arrays; Chemistry; Clusters, nanoparticles, and nanocrystalline materials; Condensed matter: structure, mechanical and thermal properties; Contact angle; Electrochemistry; Electrodes: preparations and properties; Exact sciences and technology; General and physical chemistry; Impact tests; Nanofiber; Nanofibers; Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals; Nanostructure; Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity); Physics; Pillars; Self-cleaning; Silanes; Silicone resins; Solid-fluid interfaces; Structure of solids and liquids; crystallography; Super-hydrophobicity; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Transmittance; Transparency; Wetting
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2010.04.081

Transparent super-hydrophobic films were fabricated using the PDMS method and silane process, based on anodization in phosphoric acid. Contact angle tests were performed to determine the contact angle of each film according to the anodizing time. Transmittance tests also were performed to obtain the transparency of each TPT (trimethylolpropane propoxylate triacrylate) replica film according to the anodizing time. The contact angle was determined by studying the drop shape, and the transmittance was measured using a UV-spectrometer. The contact angle increases with increasing anodizing time, because increasing pillar length can trap more air between the TPT replica film and a drop of water. The transmittance falls with increasing anodizing time because the increasing pillar length causes a scattering effect. This study shows that the pillar length and transparency are inversely proportional. The TPT replica film having nanofibers array structures was better than other films in aspect of self-cleaning by doing quantitative experimentation.