UV and thermally stable superhydrophobic coatings from sol-gel processing.
J Colloid Interface Sci
; 326(2): 465-70, 2008 Oct 15.
Article
em En
| MEDLINE
| ID: mdl-18656893
ABSTRACT
A method for the preparation of inorganic superhydrophobic silica coatings using sol-gel processing with tetramethoxysilane and isobutyltrimethoxysilane as precursors is described. Incorporation of isobutyltrimethoxysilane into silica layers resulted in the existence of hydrophobic isobutyl surface groups, thereby generating surface hydrophobicity. When combined with the surface roughness that resulted from sol-gel processing, a superhydrophobic surface was achieved. This surface showed improved UV and thermal stability compared to superhydrophobic surfaces generated from polybutadiene by plasma etching. Under prolonged UV tests (ASTM D 4329), these surfaces gradually lost superhydrophobic character. However, when the as-prepared superhydrophobic surface was treated at 500 degrees C to remove the organic moieties and covered with a fluoroalkyl layer by a perfluorooctylsilane treatment, the surface regained superhydrophobicity. The UV and thermal stability of these surfaces was maintained upon exposure to temperatures up to 400 degrees C and UV testing times of 5500 h. Contact angles remained >160 degrees with contact angle hysteresis approximately 2 degrees.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Raios Ultravioleta
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Compostos de Organossilício
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Dióxido de Silício
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Nanopartículas
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Géis
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article