Apparatus and methods employing liquid-impregnated surfaces

Abstract

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.

What is claimed is: 
     
         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) 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.   
     
     
         2 . (canceled) 
     
     
         3 . (canceled) 
     
     
         4 . (canceled) 
     
     
         5 . (canceled) 
     
     
         6 . (canceled) 
     
     
         7 . The article of  claim 1 , wherein the impregnating liquid comprises an ionic liquid. 
     
     
         8 . The article of  claim 1 , wherein the impregnating liquid comprises at least one member selected from the group consisting of 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. 
     
     
         9 . The article of  claim 1 , wherein the solid features comprise at least one member selected from the group consisting of a polymeric solid, a ceramic solid, a fluorinated solid, an intermetallic solid, and a composite solid. 
     
     
         10 . The article of  claim 1 , wherein the solid features comprise a chemically modified surface, coated surface, surface with a bonded monolayer. 
     
     
         11 . The article of  claim 1 , wherein the solid features define at least one member selected from the group consisting of pores, cavities, wells, interconnected pores, and interconnected cavities. 
     
     
         12 . The article of  claim 1 , wherein the solid features comprise at least one member selected from the group consisting of posts, nanoneedles, nanograss, substantially spherical particles, and amorphous particles. 
     
     
         13 . The article of  claim 1 , wherein the solid features have a roughened surface. 
     
     
         14 . The article of  claim 13 , wherein the roughened surface provides stable impregnation of liquid therebetween or therewithin, such that θ os(v), receding <θ c . 
     
     
         15 . The article of  claim 1 , wherein the liquid-impregnated surface is configured such that water droplets contacting the surface are not pinned or impaled on the surface and have a roll-off angle α of less than 40°. 
     
     
         16 . (canceled) 
     
     
         17 . The article of  claim 1 , wherein θ os(v), receding >0. 
     
     
         18 . 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(w),receding =0; and   (ii) θ os(v),receding =0 and θ os(w),receding =0.   
     
     
         19 . (canceled) 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . 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(v), receding >0; and   (ii) θ os(w), receding >0,   
       or wherein one or both of the following holds:
 (iii) θ os(v),receding <θ c ; and 
 (iv) θ os(w),receding <θ c , 
 
       or wherein one or both of the following holds:
 (v) θ os(v),receding <θ* c ; and 
 (vi) θ os(w),receding <θ* c , 
 
       where θ* c =cos −1  (1/r), and where r is roughness of the solid portion of the surface. 
     
     
         24 . The article of  claim 23 , wherein both θ os(v), receding >0 and θ os(w), receding >0. 
     
     
         25 . The article of  claim 23 , wherein only one or both of the following holds:
 (iii) θ os(v),receding <θ c ; and   (iv) θ os(w),receding <θ c .   
     
     
         26 . The article of  claim 23 , wherein only one or both of the following holds:
 (v) θ os(v),receding <θ* c ; and   (vi) θ os(w),receding <θ* c .   
     
     
         27 . (canceled) 
     
     
         28 . (canceled) 
     
     
         29 . (canceled) 
     
     
         30 . The article of  claim 1 , wherein the article is a pipeline or portion or coating thereof. 
     
     
         31 . The article of  claim 1 , wherein the article is a member selected from the group consisting of 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, or a portion or coating thereof. 
     
     
         32 . A method of utilizing a liquid-impregnated surface, the method comprising the steps of:
 providing an article comprising a liquid-impregnated surface, said liquid-impregnated surface comprising an impregnating liquid and a matrix of solid features spaced sufficiently close to stably contain the impregnating liquid therebetween or therewithin, said impregnating liquid and said matrix chosen such that S>0, whereby the impregnating liquid cloaks clusters upon their nucleation on the surface and restricts access of said clusters to their source medium surrounding the surface; and   using the article at equilibrium or pseudo equilibrium, thereby preventing or inhibiting one or more of: ice/frost formation on the surface, bacterial growth on the surface, formation of liquid condensate on the surface, and fouling of the surface.   
     
     
         33 . The method of  claim 32 , wherein the impregnating liquid has viscosity greater than 50 cP. 
     
     
         34 . (canceled) 
     
     
         35 . (canceled) 
     
     
         36 . An article comprising a liquid-impregnated surface, said liquid-impregnated surface comprising an impregnating liquid and a matrix of solid features spaced sufficiently close to stably contain the impregnating liquid therebetween or therewithin, said impregnating liquid and said matrix chosen such that S>0, whereby the impregnating liquid cloaks clusters upon their nucleation on the surface and restricts access of said clusters to their source medium surrounding the surface, thereby preventing or inhibiting one or more of: ice/frost formation on the surface, bacterial growth on the surface, formation of liquid condensate on the surface, and fouling of the surface. 
     
     
         37 . The article of  claim 36 , wherein the impregnating liquid has viscosity greater than 50 cP, 100 cP, or 300 cP. 
     
     
         38 . (canceled) 
     
     
         39 . (canceled) 
     
     
         40 . An article comprising an interior surface, said article being at least partially enclosed and adapted for containing or transferring a fluid of viscosity μ 1 , wherein the interior surface comprises a liquid-impregnated surface, said liquid-impregnated surface comprising an impregnating liquid and a matrix of solid features spaced sufficiently close to stably contain the impregnating liquid therebetween or therewithin, wherein the impregnating liquid comprises water (having viscosity μ 2 ). 
     
     
         41 . (canceled) 
     
     
         42 . The article of  claim 40 , wherein μ1/μ2>0.1. 
     
     
         43 . The article of  claim 40 , wherein (h/R)(μ 1 /μ 2 )>0.1 (where h is average height of the solid features and R is the radius of the pipe or the average fluid depth in an open system). 
     
     
         44 . (canceled) 
     
     
         45 . (canceled) 
     
     
         46 . The article of  claim 1 , wherein the impregnating liquid comprises an additive to prevent or reduce evaporation of the impregnating liquid. 
     
     
         47 . (canceled) 
     
     
         48 . (canceled)