Summary: | 碩士 === 國立成功大學 === 化學工程學系碩博士班 === 100 === This work aims at how to design and fabricate the transparent surfaces with tunable water wettability and adhesion. An electrostatic layer-by-layer (ELbL) assembly process was utilized to fabricate transparent and superhydrophilic nanoparticulate thin films on glass substrates, and controlling the numbers of body layer creates the different rough surface morphology in this assembly process. Degree of silanization effect on wettability and adhesion were then observed in the variation of roughness. Experiments show the rough SiO2 nanoparticulate thin films have significant influence on the surfaces in different degree of silanization, so they can perform a variety of wettability and adhesion. Different rough surface structure can also get tunable wettability and adhesion in the same degree of silanization. Furthermore, we compare the wettability and adhesion of fluorinated silane with alkylsilane. Experiments show fluorinated silane can get higher contace angle and lower contact angle hysteresis, and it can also possess more powerful hydrophobicity. Surface modification by these two silanes can acquire similar trend of the wettability and adhesion in the degree of silanization. The hysteresis and adhesion exihibit extreme variation which goes through a maximum and drop off at higher degree of silanization on SiO2 nanoparticulate thin film. But the rate of modification by using fluorinated silane is faster to modify completely, it will be eaual or rise slowly at last. Finally, making the wetting diagram does the analysis of wetting mode, and combines with the possible mechanism which we propose. Explain why smooth and rough surfaces have entirely different wetting behavior and adhesion in the degree of silanization.
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