Effect of Process Conditions on Hydrophobic Characteristics of Injection Molded Silicone Rubber Surface Replicated from Electric Discharge Machined Surface

Abstract:

In recent years, a lot of effort has gone into many researchers making components of specific functions, mimicking various microstructures in nature. In this study, a super hydrophobic surface on injection-molded liquid silicone rubber was fabricated, mimicking micro-bumps on a lotus leaf. Original patterns were machined by electric discharge machining and liquid silicone rubber was injection-molded by using the original patterns as molds. The hydrophobic characteristics of injection-molded liquid silicone rubber surface replicated from the original electric discharge machined surface were studied. According to variations of injection molding process parameters like mold temperature, injection speed, injection pressure, vacuum, etc. the variations of water contact angles, as a hydrophobic index, measured on the injection-molded surfaces were examined. The liquid silicone rubber surface molded from wire-cutting electric discharge machined surface at mold temperature 120°C, injection speed 5 mm/sec, injection pressure 70 bar and in a vacuum cavity showed water contact angle of 148°, which is close to super-hydrophobic level.

• Periodical: Applied Mechanics and Materials (Volumes 465-466)
• Pages: 1272-1276
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.465-466.1272
• Online since: December 2013
• Authors: Jeong Jin Kang*, Seok Kwan Hong, Sang Yong Lee, Sang Chul Lee, Sung Hee Lee
• Keywords: Electric Discharge Machining (EDM), Hydrophobic Surface, Liquid Silicone Rubber

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