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About: Krytox is a(n) research topic. Over the lifetime, 98 publication(s) have been published within this topic receiving 2012 citation(s).
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Journal ArticleDOI
Abstract: Thermal stabilities of perfluoropolyethers, Fomblin Z, Fomblin Y, Krytox, and Demnum in the presence of Al2O3 were examined. Fomblin Z was found to degrade at 200°C in two stages, the slow first stage, and the vigorous second stage leading to complete loss of fluid. It is concluded that oxide-to-halide conversion occurs on Al2O3 surface during the first stage. The second stage is attributed to a catalytic process induced by Lewis acid AlF3. Based on NMR and mass spectroscopic evidences the following reaction mechanism is advanced for the second stage: (1) a bidentate linkage is formed between an acidic aluminum and two oxygen atoms of an acetal unit (-O-CF2-O-) of Fomblin Z chains, and (2) the partial positive charge thus developed at the acetal carbon induces a fluorine atom transfer from the adjacent CF2 unit onto the acetal carbon and results in chain scission with transformation of the acetal sector into a methoxy end-group (-O-CF3) and the adjacent unit into either an acylfluoride end-group (FCO-CF2-), or a fluoroformate end-group (FCO-O-CF2-). Lacking acetal units Krytox and Demnum are stable against this degradation process. In the case of Fomblin Y, owing to the paucity of acetal units, no reaction was observed when heated in the presence of Al2O3; when heated with AlCl3, removal of acetal units and consequential formation of functional end-groups were observed.

151 citations

Journal ArticleDOI
01 Dec 1992-Macromolecules
Abstract: Thermal degradation of commercial perfluoropolyethers (Fomblin Z and Y, Krytox, and Demnum) and PFPEO (perfluoropoly(ethylene oxide)) in the presence of Lewis acids (metal oxides and halides) was examined. It is shown that the degradation is dominated by the intramolecular disproportionation process of the following scheme RCF 2 OCF 2 (CH 2 ) 3 OR → RCOF + CF 3 (CH 2 ) 3 OR. The reaction occurs when the two oxygen atoms flanking a monomer unit of polyether chains interact with a Lewis acid site(s). The differentail charges induced at the carbons immediately outside and inside the unit cause a fluorine transdfer and effect the disproportionation process

140 citations

Journal ArticleDOI
Abstract: Nepenthes pitcher inspired anti-wetting coatings, fluoro-SNs/Krytox, are successfully fabricated by the combination of fluoro-silicone nanofilaments (fluoro-SNs) and Krytox liquids, perfluoropolyethers. Fluoro-SNs with different microstructure are grown onto glass slides using trichloromethylsilane by simply repeating the coating step, and then modified with 1H,1H,2H,2H-perfluorodecyltrichlorosilane. Subsequently, the Krytox liquid is spread on the fluoro-SNs coatings via capillary effect. The fluoro-SNs/Krytox coatings feature ultra-low sliding angle for various liquids, excellent stability, and transparency. The sliding speed of liquid drops on the fluoro-SNs/Krytox coating is obviously slower than on the lotus inspired superhydrophobic and superoleophobic coatings, and is controlled by composition of the coating (e.g., morphology of the fluoro-SNs, type of Krytox and its thickness) and properties of the liquid drops (e.g., density and surface tension). In addition, the self-cleaning property of the fluoro-SNs/Krytox coating is closely related to properties of liquid drops and dirt.

127 citations

Journal ArticleDOI
10 Oct 2013-Langmuir
TL;DR: Hydrophobic PVDF-HFP nanowebs were fabricated by a facile electrospinning method and proposed for harvesting fog from the atmosphere and a strong adhesive force between the surface and a water droplet has been observed, which resists the water being shed from the surface.
Abstract: Hydrophobic PVDF-HFP nanowebs were fabricated by a facile electrospinning method and proposed for harvesting fog from the atmosphere. A strong adhesive force between the surface and a water droplet has been observed, which resists the water being shed from the surface. The water droplets on the inhomogeneous nanomats showed high contact angle hysteresis. The impregnation of nanomats with lubricants (total quartz oil and Krytox 1506) decreased the contact angle hysteresis and hence improved the roll off of water droplets on the nanomat surface. It was found that water droplets of 5 μL size (diameter = 2.1 mm) and larger roll down on an oil-impregnated surface, held vertically, compared to 38 μL (diameter = 4.2 mm) on a plain nanoweb. The contact angle hysteresis decreased from ∼95 to ∼23° with the Krytox 1506 impregnation.

91 citations

Journal ArticleDOI
Abstract: The inelastic scattering of gas-phase OH radicals from a liquid hydrocarbon and a liquid perfluorinated polyether (PFPE) has been investigated. The surfaces examined were the potentially reactive, branched hydrocarbon squalane (C30H62, 2,6,10,15,19,23-hexamethyltetracosane) and the inert PFPE Krytox 1506 (F−[CF(CF3)CF2O]14ave−CF2CF3). Superthermal OH was formed by 355-nm laser photolysis of a low pressure of HONO above the liquid surface. Laser-induced fluorescence (LIF) was used to determine the relative yields and nascent translational and rotational distributions of OH (v′ = 0). The time-of-flight profiles from both liquids can be resolved, at least empirically, into two components. The dominant, faster component is consistent with direct, inelastic scattering. It has a higher average translational energy from PFPE than from squalane. This faster OH also has a higher Boltzmann-like rotational temperature for PFPE (655 ± 45 K) than for squalane (473 ± 27 K), in both cases considerably hotter than the in...

73 citations

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Topic's top 5 most impactful authors

William R. Jones

7 papers, 67 citations

Rapee Gosalawit

4 papers, 109 citations

Deepak Tapriyal

4 papers, 37 citations

Paul H. Kasai

4 papers, 324 citations

Teresa Casimiro

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