Apparatus and methods employing liquid-impregnated surfaces
In certain embodiments, the invention is directed to apparatus comprising a liquid-impregnated surface, said surface comprising an impregnating liquid and a matrix of solid features spaced sufficiently close to stably contain the impregnating liquid therebetween or therewithin, and methods thereof. In some embodiments, one or both of the following holds: (i) 0<ϕ≤0.25, where ϕ is a representative fraction of the projected surface area of the liquid-impregnated surface corresponding to non-submerged solid at equilibrium; and (ii) S ow(a) <0, where S ow(a) is spreading coefficient, defined as γ wa −γ wo −γ oa , where γ is the interfacial tension between the two phases designated by subscripts w, a, and o, where w is water, a is air, and o is the impregnating liquid.
1. An article comprising a liquid-impregnated surface, said surface comprising an impregnating liquid and a matrix of solid features spaced sufficiently close to stably contain the impregnating liquid therebetween or therewithin, wherein one or both of the following holds:
(i) θ os(e),receding =0; and
(ii) θ os(v),receding =0 and θ os(e),receding =0,
where θ os(e),receding is receding contact angle of the impregnating liquid on the surface (subscript ‘s’) in the presence of a non-vapor (e.g., liquid, solid, semi-solid, gel) phase external to the surface that is different from the impregnating liquid (subscript ‘e’), and where θ os(v),receding is receding contact angle of the impregnating liquid (e.g., oil, subscript ‘o’) on the surface (subscript ‘s’) in the presence of vapor phase (subscript ‘v’, e.g., air).
2. The article of claim 1 , further comprising material of said non-vapor phase external to said surface (and in contact with said surface), said article containing said non-vapor phase material.
3. The article of claim 2 , wherein said material of said non-vapor phase external to said surface comprises one or more of the following: food, cosmetic, cement, asphalt, tar, ice cream, egg yolk, water, alcohol, mercury, gallium, refrigerant, toothpaste, paint, peanut butter, jelly, jam, mayonnaise, ketchup, mustard, condiment, laundry detergent, consumer product, gasoline, petroleum product, oil, biological fluid, blood, plasma.
4. The article of claim 1 , wherein the article is a container, a pipeline, a nozzle, a valve, a conduit, a vessel, a bottle, a mold, a die, a chute, a bowl, a tub, a bin, a cap, and/or a tube.
5. The article of claim 1 , wherein θ os(e),receding =0.
6. The article of claim 1 , wherein the article comprises an interior surface that is at least partially enclosed, the interior surface containing or transferring the phase external to the surface and having a viscosity μ 1 , wherein the interior surface comprises the liquid-impregnated surface, wherein the impregnating liquid is aqueous (having viscosity μ 2 ).
7. The article of claim 6 , wherein the article is a member selected from the group consisting of a pipeline, a steam turbine part, a gas turbine part, an aircraft part, a wind turbine part, eyeglasses, a mirror, a power transmission line, a container, a windshield, an engine part, tube, nozzle, or a portion or coating thereof.
8. The article of claim 6 , wherein μ 1 / μ 2 >0.1.
9. The article of claim 6 , wherein the impregnating liquid comprises an additive (e.g., a surfactant) to prevent or reduce evaporation of the impregnating liquid.
10. The article of claim 1 , wherein the impregnating liquid comprises at least one member selected from the group consisting of silicone oil, propylene glycol dicaprylate/dicaprate, perfluoropolyether (PFPE), polyalphaolefin (PAO), synthetic hydrocarbon cooligomer, fluorinated polysiloxane, propylene glycol, tetrachloroethylene (perchloroethylene), phenyl isothiocyanate (phenyl mustard oil), bromobenzene, iodobenzene, o-bromotoluene, alpha-chloronaphthalene, alpha-bromonaphthalene, acetylene tetrabromide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (BMIm), tribromohydrin (1,2,3-tribromopropane), ethylene dibromide, carbon disulfide, bromoform, methylene iodide (diiodomethane), stanolax, Squibb's liquid petrolatum, p-bromotoluene, monobromobenzene, perchloroethylene, carbon disulfide, phenyl mustard oil, monoiodobenzene, alpha-monochloro-naphthalene, acetylene tetrabromide, aniline, butyl alcohol, isoamyl alcohol, n-heptyl alcohol, cresol, oleic acid, linoleic acid, and amyl phthalate.