Preparation And Investigation Of Nano-structural Functional Super-hydrophobic Surface

Wettability is very important property of solid surface, and is governed by thesurface chemical composition and geometrical structures. Recently,super-hydrophobic surface, with a water contact angle (CA) higher than 150°, hasattracted much interest because it will bring great convenience on our daily life aswell as in many industrial and agricultural processes. Conventionally,super-hydrophobic surface can be effectively fabricated by constructingappropriate surface roughness on low surface energy Materials. In this present thesis, we reported two kinds of super-hydrophobic surfaces.Firstly, through bio mimicking the gecko toe like surface structures, we obtained asuper-hydrophobic surface with a high adhesive force to water. Secondly,through constructing cauliflower like surface structures, we obtained anothersuper-hydrophobic surface with a low adhesive force to water. Experimentresults show that surface structures can greatly influent the adhesive interactionsbetween super-hydrophobic surface and the water. 1. Using a templated method, we obtained super-hydrophobic Aligned PS nanotubes films with a water contact angle as high as 162.0°. We find that such films have a high adhesive force to water, the water on such surface does not roll or break away even the films was 90 degree titled or turned up-side down. Such high adhesive force is ascribed to the high capillary III吉林大学博士学位论文 英文摘要 force of the aligned nanotubes. This discovery offer us opportunity for further understand the wettability of solid surface as well as for industrial applications such as in lostless liquid transportion and micro-sample analysis systems. 2. Using the template method, we prepared aligned polymethyl methacrylate (PMMA) nanopole films. Without any low surface energy material modification, the films show super-hydrophobicity with a water contact angle as high as 152.0°. Such super-hydrophobicity is ascribed to the high air fraction on the rough nanopole PMMA films. 3. Using a laser cutting method, we prepared cabbage-like polymer films. Wettability studies reveals that the films show super-hydrophobic property with a high water contact angle of about 165.7 ± 0.3° and a low sliding angle (less than 5°). Water droplet moved easily on the surface. The as-prepared films have a very low adhesive force to water. The sliding feature was strongly affected by microstructure of surface. This information was useful for the designing of bio-mimetic hydrophobic surface structure for variety of applications. These surfaces may provide very effective water-repellent and anti-adhesive properties against particular contamination. 4. Using the as-prepared rough PDMS surface as a stamp, we prepared micro-nano hierarchical surface on PS film, the water CA on it is as high as 161.2°. The surface structures on the as-prepared PS films are similar to the structures on PDMS stamp. Such simple method could be facilely used to other thermoplastics such as PE, PMMA, PC and so on, to produce super-hydrophobic materials.