Fluorocarbon Crowning: Langmuir-Blodgett Deposition versus Self-Assembly at Molecularly Rough Surfaces

详细信息    查看全文

• 作者：Donald H. McCullough III ; Ruslan Grygorash ; Steven L. Regen
• 刊名：Langmuir
• 出版年：2007
• 出版时间：September 11, 2007
• 年：2007
• 卷：23
• 期：19
• 页码：9606 - 9610
• 全文大小：128K
• 年卷期：v.23,no.19(September 11, 2007)
• ISSN：1520-5827

文摘

Langmuir-Blodgett deposition of a single monolayer of 1,2,4,5-tetrakis[(N-(perfluoroundecanoamidoethyl)-N,N-dimethylammonium)methyl]benzene tetrabromide (1) onto a thin film made from alternating layers of poly(diallydimethylammonium chloride) (PDADMA) and poly(4-styrenesulfonate) (PSS) ions affords a uniform fluorinatedsurface of low energy. An analogous surface that has been constructed by self-assembly shows the same critical surfacetension of 16.5 dyn/cm. A comparison of Zisman plots for these two modified films, in combination with analysisby X-ray photoelectron spectroscopy, indicates that Langmuir-Blodgett deposition produces a higher quality andmore densely packed fluorocarbon surface that is very hydrophobic. In sharp contrast, the use of a single-chain analog(i.e., N-(perfluoroundecanoamidoethyl)-N,N,N-trimethylammonium bromide) (2)) affords relatively high energy surfacesby Langmuir-Blodgett deposition and by self-assembly.