Control of hydrophobic character of super-water-repellent surface by UV irradiation

Chemistry Letters

Volumn , Issue 4, 1998, Pages 293-294

  Sasaki, Hiroshi ^a   Shouji, Mitsuyoshi ^a  

^a HITACHI LTD   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0032386140     PISSN: 03667022     EISSN: None     Source Type: Journal    
DOI: 10.1246/cl.1998.293     Document Type: Article

References (14)

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3. T. Onda, S. Shibuichi, N. Satoh, and K. Tsujii, Oyobuturi, 64, 788 (1996). (in Japanese)
4. Y. Tei, Engineering Materials, 44, No.8, 30 (1996). (in Japanese)
5. H. Kobayashi, Engineering Materials, 44, No.8, 38 (1996). (in Japanese)
6. G. Yamauchi and T. Ueda, Engineering Materials, 44, No.8, 42 (1996). (in Japanese)
7. M. Irie, J. Am. Chem. Soc., 105, 2078 (1983).
8. Compound 2 was obtained by two steps of amidation reactions. In the first step, one of the amino groups of 1,4-bis(4-aminophenoxy)benzene reacts with benzoyl chloride, while in the second step, the other amino group reacts with poly (perfluoroisopropyleneoxy)carbonylchloride. Poly (perfluoroisopropyleneoxy) carbonylchloride was obtained by chlorination of poly(perfluoroisopropyleneoxy) carboxylic acid (Krytox 157 FS-L, E. I. du Pont de Nemours & Co. Inc. USA) using thionyl chloride. Satisfactory spectral data were obtained for 2.
9. 2-3
10. All measurements were repeated at least three times and the repeatability of the results was better than 10 degrees. As test plates were not perfectly horizontal, a water drop moved on the surfaces when the contact angle was more than 150 degrees. Therefore we assumed that the surface showed a contact angle of more than 150 degrees is a super-water-repellent surface.
11. 14 Before UV irradiation, fractal dimension of the surface was 2.29. However after UV irradiation, the fractal dimension was 2.37. Before coating compound 1, the fractal dimension of the surface that shows super-water-repellency was 2.34.
12. H. Sasaki, A. Ueno, and T. Osa, Bull. Chem. Soc. Jpn., 61, 2321 (1988).
13. M. Irie and D. Kunwatchakun, Macromolecules, 19, 2476 (1986).
14. P. I. Oden, A. Majumdar, B. Bhushan, A. Padmanabhan, and J. J. Graham, ASME J. Trib., 114, 666 (1992).