Preparation of Superhydrophobic Films by Plasma Technology

• Main Authors: Shih-Hsien Yang, 楊士賢
• Other Authors: Hui Chen
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/13576794490042169142

博士 === 國立中央大學 === 化學工程與材料工程研究所 === 97 === In this paper, the superhydrophobic films were prepared rapidly in one step by adjusting various parameters. Besides, the physical, chemical, mechanical strength, and optical properties were analyzed and discussed. The plasma deposition mechanisms were also discussed through above results as following: First, super-hydrophobic films were deposited in one-step simple process by pulsed RF C6F6 plasma, and the influence of duty-cycle (DC) on the surface structure and chemical characteristics of depositing fluorocarbon films were investigated. It was found that with decreasing the DC from 1 to 0.1, the rough structure of the film which had a lot of particles was obtained. Besides, this composite structure with low surface energy resulted in exhibiting the desirable super-hydrophobic surface property. Finally, the fluorocarbon films were prepared on cotton substrate and the adhesion on the substrate was strong. Second, the silicon wafer and plastic substrate have been coated silica films by Plasma enhanced chemical vapor deposition (PECVD). The films were deposited by introducing Ethoxytrimethylsilane (EOTMS), Diethoxydimethylsilane (DEODMS) and Methyltriethoxysilane (MTEOS) into the RF bell jar reactor fed with different oxygen flow rate. When adding oxygen into PECVD reactor, SiOx films with hardness 8H were deposited on hard silicon wafer. On the other hand, the SiOx film with 5B degree adhesion, 7H degree hardness, and hydrophobic characteristic could be obtained when a buffer layer was coated between the 1500nm-thick of SiOx film and the PMMA substrate. Third, the chemical properties and surface morphology of superhydrophobic (SH) films deposited by self-assembled RF atmospheric-pressure plasma jet (APPJ) deposition system was investigated. The O2/HMDSN (hexamethyldisilazane) and Ar serve as the deposition precursor and ionization gas, respectively. Consequently, the smooth surface was transformed into a rough surface with many particles when the nozzle-to-sample distance was decreased from 20 mm to 10 mm. The SH films (contact angle over 150° and sliding angle below 5°) were obtained when the nozzle-to-sample distance was 10 mm. A simplified deposition mechanism is proposed to explain the effect of process parameters on the films that are formed. Finally, the film was coated on the conductive and the non-conducting glass by APPJ system. It was found that the Arc condition would be produced on the conductive glass, and the superhydrophobic films ( contact angle: 170o, sliding angle: 2.2o ) could be prepared using the HMDSN monomer by Arc-APPJ. Besides, the absolute optical transmittance of the film increased with increasing the speed of stage. Finally, the transparent superamphiphobic film (WCA: 169o, OWA: 146.9o and Tavg: 97.1%) could be prepared rapidly in optimum condition (150 mm/s) by Arc-APPJ.