Wetting Behavior of Liquids on Micro-Patterned Polymer Surfaces Fabricated by Thermal Imprinting

다국어 초록 (Multilingual Abstract)

Abstract: The wetting behavior of liquids on solid surfaces is important in the study of surfaces and interfaces. In this study, the wetting behavior of deionized (DI) water and hexadecane on fluorinated and micro-patterned polymer surfaces was investigated. The sample surfaces were processed by spray coating and thermal imprinting, respectively. The apparent contact angle and sliding angle of each sample were measured. Hexadecane, which has a low surface tension, spread easily over the micro-patterned surface, indicating oleophilicity. However, the apparent contact angle of DI water on the micro-patterned surface was approximately 134.2°, indicating that the surface was hydrophobic. Although the apparent contact angle of DI water on the micro-patterned surface indicated hydrophobicity, the sliding angle was very high at 60º. These results indicated that DI water droplets on the micro-patterned surfaces have an intermediate wetting state between the Wenzel and Cassie-Baxter states. Based on the experimental results, it was concluded that the wetting behavior of DI water droplets on the micro-patterned surfaces is determined by the force balance between the capillary force and the air counterforce. (Received April 3, 2017; Accepted May 14, 2017)