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HERO ID
3860670
Reference Type
Journal Article
Title
Effect of end-groups on simultaneous oleophobicity/hydrophilicity and anti-fogging performance of nanometer-thick perfluoropolyethers (PFPEs)
Author(s)
Wang, Y; Knapp, J; Legere, A; Raney, J; Li, Lei
Year
2015
Is Peer Reviewed?
1
Journal
RSC Advances
EISSN:
2046-2069
Volume
5
Issue
39
Page Numbers
30570-30576
DOI
10.1039/c5ra04483a
Web of Science Id
WOS:000352791300023
Abstract
Simultaneously oleophobic/hydrophilic coatings are highly desirable in many important applications, e.g., anti-fogging. However, to date, such coatings have been rarely reported and the underlying mechanisms remain unclear. In the current paper, the wetting behavior of three nanometer-thick perfluoropolyether (PFPE) polymers with the same backbone but different end-groups has been studied by contact angle tests and the underlying mechanisms governing the simultaneous oleophobicity/hydrophilicity have been investigated. The experimental results indicated that the end-groups of the nanometer-thick PFPEs are critical to the simultaneous oleophobicity/hydrophilicity. PFPE polymers with different end-groups can interact with the substrate in very different ways, resulting in different packing orders and thus different inter-chain distances within the polymer nanofilms. If the inter-chain distance is appropriately small, smaller water molecules penetrate the nanofilms quickly while larger oil molecules penetrate the nanofilms much more slowly. As a result, the surface shows a higher oil contact angle (OCA) than WCA, i.e., simultaneous oleophobicity/hydrophilicity. Moreover, the effect of simultaneous oleophobicity/ hydrophilicity on the long-term anti-fogging capability has been studied by X-ray photoelectron spectroscopy (XPS) and anti-fogging tests. The results indicated that the unique simultaneous oleophobicity/hydrophilicity reduces the airborne hydrocarbon contamination and therefore improves the long-term anti-fogging performance.
Tags
PFAS
•
Expanded PFAS SEM (formerly PFAS 430)
Perfluoropentanesulfonate
•
^Per- and Polyfluoroalkyl Substances (PFAS)
PFPeS (2706-91-4)
Literature Search
WOS
•
PFPeS
Literature Search
WOS
Screening Results
Excluded/Not on Topic
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