FLUID RESISTANT COATINGS FOR SUBSTRATES

Abstract

Articles that are oleophobic and/or hydrophobic, as well as associated methods, are generally provided. In some embodiments, articles described herein do not comprise fluorinated polymers. Articles described herein may comprise nanostructures that contribute to their hydrophobicity and/or their oleophobicity. Articles described herein may have high wash resistance.

Claims

1. An article, comprising: a substrate comprising a surface, wherein the substrate comprises a textile; a plurality of nanostructures comprising a polymer on the surface of the substrate; and a layer comprising a polymerized silane and/or a polymerized siloxane, wherein the layer covers at least a portion of the surface and at least a portion of the plurality of nanostructures, and wherein a surface of the article is hydrophobic and/or oleophobic.

2. The article of claim 1, wherein the layer comprising the polymerized silane and/or the polymerized siloxane has an elastic modulus of greater than or equal to 1 GPa and less than or equal to 5 GPa.

3-9. (canceled)

10. A method of forming an article, comprising: forming a first layer comprising a polymer on a surface of a substrate by exposing the surface of the substrate to a first plasma comprising a monomer; etching the first layer by exposing the first layer to a second plasma to form an etched first layer; and forming a second layer comprising a polymerized silane and/or a polymerized siloxane on the etched first layer.

11. The method of claim 10, wherein the first layer has an elastic modulus of greater than or equal to 4 GPa and less than or equal to 12 GPa.

12. The method of claim 10, wherein the second layer has an elastic modulus of greater than or equal to 0.5 GPa and less than or equal to 2 GPa.

13. A method of forming an article, comprising: forming a layer comprising a polymer on a surface of a textile by exposing the surface of the textile to a first plasma comprising ethylene, butadiene, acetylene, methane, methanol, ethanol, or a combination thereof; and etching the layer using a second plasma comprising oxygen, argon, helium, neon, krypton, xenon, or a combination thereof.

14. (canceled)

15. The method of claim 10, wherein the first plasma has a pressure of greater than or equal to 20 Pa and less than or equal to 80 Pa and/or the second plasma has a pressure of greater than or equal to 40 Pa and less than or equal to 80 Pa.

16. The method of claim 10, wherein the first plasma is supplied a power of greater than or equal to 500 W and less than or equal to 1000 W.

17-18. (canceled)

19. The method of claim 13, forming a second layer comprising a polymerized silane and/or a polymerized siloxane on the etched first layer.

20. The method of claim 19, wherein the second layer is formed by exposing the substrate to a third plasma comprising a silane and/or a siloxane on the etched first layer.

21-42. (canceled)

43. The article of claim 1, wherein the plurality of nanostructures are discrete nanostructures.

44. The article of claim 1, wherein at least a portion of the plurality of nanostructures are isolated nanostructures that are not in contact with other nanostructures.

45. The article of claim 1, wherein the article has a surface with an average RMS roughness of greater than or equal to 0.01 microns and less than or equal to 0.13 microns.

46. (canceled)

47. The article of claim 1, wherein the plurality of nanostructures has an average diameter of greater than or equal to 0.12 microns and less than or equal to 0.38 microns.

48. (canceled)

49. The article of claim 1, wherein an average peak-to-peak spacing between the plurality of nanostructures is greater than or equal to 0.22 microns and less than or equal to 2.1 microns.

50. (canceled)

51. The article of claim 1, wherein the substrate/textile has an elastic modulus of greater than or equal to 20 kPa and less than or equal to 80 kPa.

52. The article of claim 1, wherein the hydrophobicity rank of the article is greater than or equal to 4 and less than or equal to 8 when measured using AATCC TM 193-2017.

53. The article of claim 1, wherein the oleophobicity rank of the article is greater than or equal to 2 and less than or equal to 6 when measured using AATCC TM 118-2017.

54. The article of claim 1, wherein the hydrophobicity rank of the article is greater than or equal to 2 and less than or equal to 8 when measured using AATCC TM 193-2017 after performing greater than or equal to 10 wash cycles and less than or equal to 15 wash cycles performed according to ISO W6330:2012(E).

55. The article of claim 1, wherein the oleophobicity rank of the article is greater than or equal to 1 and less than or equal to 6 when measured using AATCC TM 118-2017 after performing greater than or equal to 10 wash cycles and less than or equal to 15 wash cycles performed according to ISO W6330:2012(E).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Non-limiting embodiments of the present disclosure will be described by way of example with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale unless otherwise indicated. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the disclosure shown where illustration is not necessary to allow those of ordinary skill in the art to understand the disclosure. In the figures:

[0013] FIGS. 1A-1B provide schematic, cross-sectional illustrations of droplets contacting non-limiting articles, according to some embodiments;

[0014] FIG. 2 provides a schematic, cross-sectional illustration of a method of forming an article comprising nanostructures, according to some embodiments;

[0015] FIG. 3 provides a schematic, cross-sectional illustration of a method of forming an article comprising nanostructures, according to some embodiments;

[0016] FIGS. 4A-4D provide profilometry measurements of non-limiting articles comprising nanostructures, according to some embodiments;

[0017] FIGS. 5A-5D provide scanning electron micrographs of non-limiting articles comprising nanostructures, according to some embodiments;

[0018] FIG. 6A provides a scanning electron micrograph of a non-limiting substrate comprising a textile, according to some embodiments; and

[0019] FIG. 6B provides a scanning electron micrograph of a non-limiting article comprising nanostructures on a textile, according to some embodiments.

DETAILED DESCRIPTION

[0020] Articles comprising hydrophobic and/or oleophobic surfaces, and associated methods, are generally described. Hydrophobic and/or oleophobic surfaces have a number of important applications, including in the textile industry where there is high demand for water resistant and/or oil resistant textiles (e.g., for clothing, tents, etc.). The present disclosure is directed towards improved hydrophobic and/or oleophobic surfaces on substrates. The technology and embodiments described herein may have a number of particular advantages for the fabrication of hydrophobic and/or oleophobic textiles or fabrics. For example, in some embodiments, the methods herein are directed towards the fabrication of non-fluorinated hydrophobic and/or oleophobic surfaces on textile substrates, which may provide a number of environmental and performance-related advantages. It should be appreciated, however, that the technology and embodiments herein may be applicable to other types of substrates and applications.

[0021] In a first aspect, a method of forming an article is generally described. A method may comprise forming one or more nanostructures on a surface of a substrate. Without wishing to be bound by any particular theory, the presence of nanostructures on a substrate may produce a nanoscale texture that can improve the hydrophobicity and/or oleophobicity of a substrate, relative to a substrate comprising a layer of the same material without the nanostructures, all other factors being equal. For example, FIG. 1A provides a schematic cross-sectional illustration of a nonlimiting flat substrate 101 in contact with a water droplet 103 to create a contact angle 105 defined by a direction 107 at which the surface of water droplet 103 contacts substrate 101. The contact angle of a particular liquid phase (e.g., water) on a substrate is measured through the bulk of the liquid phase. Generally, higher water contact angles are associated with more hydrophobic and/or oleophobic interfaces.

[0022] In contrast to FIG. 1A, FIG. 1B provides a cross-sectional, schematic illustration of a nonlimiting substrate 102 comprising nanostructures 111. As shown in FIG. 1B, a contact angle 105 between a water droplet 103 and a substrate 102 is greater than the contact angle 105 shown in FIG. 1A as a result of the presence of nanostructures 111. Without wishing to be bound by any particular theory, the increase in contact angle resulting from the presence of nanostructures may be attributable to the presence of an ambient gas between nanostructures 111. An advantage of some methods described herein is the formation of such nanostructures on the surface of textiles or fabrics, which has been difficult to achieve prior to the present disclosure. It should be appreciated that while FIG. 1B shows nanostructures that are regularly sized and spaced, in other embodiments other shapes, sizes, and spacing of nanostructures are possible, as described in more detail herein. For instance, in some embodiments, heterogeneous nanostructures are formed (e.g., nanostructures having different heights, widths, diameters, and/or lengths, etc.).

[0023] In some embodiments, a method comprises forming nanostructures using a plasma. A method may comprise a first step of exposing a substrate to a plasma. FIG. 2 presents a schematic illustration of a nonlimiting example of such a method. In a first method step 250, a substrate 201 is exposed to a first plasma 220 to produce a plurality of nanostructures 207 on a surface of substrate 201. According to some embodiments, the plasma may be used to chemically vapor deposit nanostructures on the surface of a substrate (e.g., a textile or fabric). Without wishing to be bound by any particular theory, in some embodiments, the nanostructures are formed by an island growth mechanism. As shown illustratively in FIG. 2, the resulting nanostructures may be discrete entities that are separated and isolated from other nanostructures (e.g., the nanostructures are unconnected from each other and/or are separated from each other by a material that is different from the material forming the nanostructures). As described herein and with respect to this figure, in some embodiments, nanostructures are formed using a top down approach that does not involve etching of a substrate. In other words, the process lacks an etching step.

[0024] In some embodiments, the method shown in FIG. 2 may be used to form heterogeneous nanostructures (e.g., nanostructures having different heights, widths, diameters, and/or lengths, etc.). In some embodiments, the method may be used to form homogeneous nanostructures. In other embodiments, the method may be used to form heterogenous nanostructures.

[0025] A plurality of nanostructures may be formed on a substrate by exposing a surface of the substrate to a plasma comprising a monomer. In some embodiments, exposing a surface of a substrate to a plasma that comprises a monomer produces an article with a plurality of nanostructures on a surface of the substrate. A plurality of nanostructures may comprise a polymer (e.g., a polymerized monomer of the monomers present in the plasma).

[0026] Any of a variety of suitable plasmas may be used to produce a plurality of nanostructures on a surface of an article. In some embodiments, a plasma may comprise a monomer. For example, a plasma may comprise an organic monomer, such as a hydrocarbon monomer. According to some embodiments, a method comprises polymerizing monomers (e.g., hydrocarbon monomers) from a plasma to form a polymer nanostructure during plasma deposition. A nanostructure formed by plasma deposition may be or comprise a polymerized form of a monomer in the plasma. Thus, an organic monomer such as a hydrocarbon monomer may be polymerized by the plasma to produce an organic polymer such as a hydrocarbon polymer. Methods disclosed herein may allow the formation of polymer nanostructures via an island growth mechanism that does not involve masking or patterning. Forming nanostructures by island growth may have any of a variety of advantages for producing hydrophobic and/or oleophobic coatings on substrates. For example, island growth mechanisms may be scalable to large substrate surfaces, and/or may be suitable for the coating of textile substrates.

[0027] Any of a variety of suitable monomers may be used in a plasma. In some embodiments, a plasma comprises an organic monomer such as ethylene, butadiene acetylene, methane, methanol, or ethanol. In some embodiments, the organic monomer may be a hydrocarbon monomer (e.g., ethylene, butadiene, acetylene, or methane). In some embodiments, plasma deposition of organic monomers forms an organic polymer. In some embodiments, a plasma comprises a silicon-based monomer such as a silane (e.g., tetramethylorthosilicate, tetraethylorthosilicate, hexadecyltrimethoxysilane, or vinyltrimethylsilane) or a siloxane (e.g., hexamethyldisiloxane, hexadecyltrimethoxysilane, or hexaethyldisiloxane), or combinations thereof. A plasma may comprise exactly one type of monomer or a combination of types of monomers. In some embodiments, a plasma used for depositing nanostructures described herein does not include a silane or a siloxane.

[0028] In some embodiments, a plasma used for nanostructure deposition comprises a reactive species. For example, a plasma may comprise a reactive species such as such as oxygen, argon, helium, neon, krypton, xenon, or combination thereof. In some embodiments, a reactive species reacts with monomers of a plasma prior to deposition of the monomers onto a substrate. Reaction of the monomers with the reactive species may result in the formation of radicalized monomers of the plasma. Radicalized monomers may deposit on the substrates at different rates, and may impact the plasma conditions appropriate for nanostructure deposition.

[0029] A plasma suitable for depositing a nanostructure (e.g., plasma 220 of FIG. 2) described herein may be used in a chamber having any of a variety of suitable pressures. In some embodiments, a plurality of nanostructures are plasma-deposited in a chamber having a pressure of greater than or equal to 0.01 Pa, greater than or equal to 0.02 Pa, greater than or equal to 0.05 Pa, greater than or equal to 0.1 Pa, greater than or equal to 0.2 Pa, greater than or equal to 0.5 Pa, greater than or equal to 1 Pa, greater than or equal to 2 Pa, greater than or equal to 5 Pa, or greater than or equal to 10 Pa. In some embodiments, a plurality of nanostructures are plasma-deposited in a chamber having a pressure of less than or equal to 20 Pa, less than or equal to 15 Pa, less than or equal to 10 Pa, less than or equal to 5 Pa, less than or equal to 2 Pa, less than or equal to 1 Pa, less than or equal to 0.5 Pa, less than or equal to 0.2 Pa, less than or equal to 0.1 Pa, less than or equal to 0.05 Pa, or less than or equal to 0.02 Pa. Combinations of these ranges are also possible (e.g., greater than or equal to 0.01 Pa and less than or equal to 20 Pa or greater than or equal to 0.1 Pa and less than or equal to 10 Pa). Other ranges are also possible. A suitable plasma pressure may be chosen, for example, to produce nanostructures instead of a uniform layer.

[0030] Generally, the plasmas described herein are provided with power. The power is radio-frequency (RF) power or microwave (MW) power, in some embodiments. A plasma for depositing a nanostructure (e.g., plasma 220 of FIG. 2) may have any of a variety of suitable powers. In some embodiments, a plasma for depositing a nanostructure has a power of greater than or equal to 800 W, greater than or equal to 820 W, greater than or equal to 850 W, greater than or equal to 880 W, greater than or equal to 900 W, greater than or equal to 920 W, greater than or equal to 950 W, greater than or equal to 980 W, greater than or equal to 1000 W, greater than or equal to 1020 W, greater than or equal to 1050 W, greater than or equal to 1080 W, greater than or equal to 1100 W, greater than or equal to 1120 W, greater than or equal to 1150 W, greater than or equal to 1180 W, greater than or equal to 1200 W, greater than or equal to 1220 W, greater than or equal to 1250 W, or greater than or equal to 1280 W. In some embodiments, a plasma for depositing a nanostructure has a power of less than or equal to 1300 W, less than or equal to 1280 W, less than or equal to 1250 W, less than or equal to 1220 W, less than or equal to 1200 W, less than or equal to 1180 W, less than or equal to 1150 W, less than or equal to 1120 W, less than or equal to 1100 W, less than or equal to 1080 W, less than or equal to 1050 W, less than or equal to 1020 W, less than or equal to 1000 W, less than or equal to 980 W, less than or equal to 950 W, less than or equal to 920 W, less than or equal to 900 W, less than or equal to 880 W, less than or equal to 850 W, or less than or equal to 820 W. Combinations of these ranges are also possible (e.g., greater than or equal to 800 W and less than or equal to 1300 W or greater than or equal to 900 and less than or equal to 1250 W). Other ranges are also possible.

[0031] A method may comprise depositing a layer on a substrate. The term layer generally refers to an arrangement of material that, when the material is laid flat, has a thickness dimension, a depth dimension that is perpendicular to the thickness dimension, and a width dimension that is perpendicular to both the thickness dimension and the depth dimension, where the lengths of each of the depth dimension and the width dimension are at least 3 times the length of the thickness dimension. In some embodiments, the length of the depth dimension of the layer is at least 5 times, at least 10 times, at least 25 times, at least 50 times, at least 100 times, at least 500 times, or at least 1000 times the length of the thickness dimension of the layer. In some embodiments, the length of the width dimension of the layer is at least 5 times, at least 10 times, at least 25 times, at least 50 times, at least 100 times, at least 500 times, or at least 1000 times the length of the thickness dimension of the layer. The width and depth dimensions of a layer define its major surfaces. In some embodiments, the substrate is also a layer.

[0032] In some embodiments, a method comprises depositing a layer of material on top of a plurality of nanostructures on a substrate. For example, referring again to FIG. 2, a method step 252 comprises depositing a layer 213 on top of nanostructures 207. A layer formed on top of a plurality of nanostructures may retain a texture of the plurality of nanostructures. For example, as shown in FIG. 2, layer 213 retains a texture that includes hills 297 (e.g., the layer is higher above nanostructures 207) and valleys 299 (e.g., the layer is lower elsewhere). A layer having such undulations (e.g., hills and valleys, protrusions and indentations) positioned on top of a plurality of nanostructures may have increased oleophobicity and/or hydrophobicity relative to an analogous flat layer having an identical composition (e.g., absent the nanostructures, all other factors being equal), since the layer's texture may create the same increase in contact angle described above with reference to FIG. 1B. For instance, the increase in oleophobicity and/or hydrophobicity and/or contact angle resulting from the presence of the layer over the nanostructures may be attributable to the presence of an ambient gas between the nanostructures.

[0033] A layer may be deposited by any of a variety of appropriate methods. In some embodiments, a layer is deposited using plasma. For example, as shown in FIG. 2, layer 213 is deposited using a plasma 222. A plasma used to deposit a layer may comprise a monomer such as an organic monomer and/or a silicon-based monomer (e.g., a silane or a siloxane). Appropriate types of organic and silicon-based monomers are discussed above, in the context of plasmas used to form nanostructures-any monomer listed there may be used for layer formation.

[0034] According to some embodiments, a method comprises polymerizing monomers from a plasma to form a layer. A layer formed by plasma deposition may comprise a polymerized form of a monomer in the plasma (i.e., a polymer formed from plasma polymerization). Appropriate pressure and power conditions for the plasma may be used to form a uniform layer. In some embodiments, a layer of an article comprises an organic polymer, a polymerized silane and/or a polymerized siloxane. In some embodiments, a layer comprises exactly one polymer selected from the group consisting of an organic polymer, a polymerized silane and/or a polymerized siloxane. However, in other embodiments a layer may comprise two or more polymers selected from the group consisting of an organic polymer, a polymerized silane and/or a polymerized siloxane. The composition of a layer may be homogeneous, or may comprise a composition gradient (e.g., along the depth dimension of the layer), as described in more detail below.

[0035] In some embodiments, a plasma used for layer deposition comprises a reactive species. For example, a plasma may comprise a reactive species such as such as oxygen, argon, helium, neon, krypton, xenon, or combination thereof. In some embodiments, a reactive species may etch a layer as the layer is deposited (as discussed in greater detail below). However, in some embodiments, a reactive species reacts with monomers of a plasma prior to deposition of the monomers onto a substrate. Reaction of the monomers with the reactive species may result in the formation of radicalized monomers of the plasma. Radicalized monomers may deposit on the substrates at different rates, and may cause changes to properties of a deposited layer.

[0036] A plasma suitable for depositing a layer (e.g., plasma 222 of FIG. 2) described herein may be used in a chamber having any of a variety of suitable pressures. In some embodiments, a layer is plasma-deposited in a chamber having a pressure of greater than or equal to 5 Pa, greater than or equal to 10 Pa, greater than or equal to 15 Pa, greater than or equal to 20 Pa, greater than or equal to 25 Pa, greater than or equal to 30 Pa, greater than or equal to 35 Pa, greater than or equal to 40 Pa, greater than or equal to 45 Pa, greater than or equal to 50 Pa, greater than or equal to 55 Pa, greater than or equal to 60 Pa, greater than or equal to 65 Pa, greater than or equal to 70 Pa, greater than or equal to 75 Pa, greater than or equal to 80 Pa, or greater than or equal to 85 Pa. In some embodiments, a layer is plasma-deposited in a chamber having a pressure of less than or equal to 90 Pa, less than or equal to 85 Pa, less than or equal to 80 Pa, less than or equal to 75 Pa, less than or equal to 70 Pa, less than or equal to 65 Pa, less than or equal to 60 Pa, less than or equal to 55 Pa, less than or equal to 50 Pa, less than or equal to 45 Pa, less than or equal to 40 Pa, less than or equal to 35 Pa, less than or equal to 30 Pa, less than or equal to 25 Pa, less than or equal to 20 Pa, less than or equal to 15 Pa, or less than or equal to 10 Pa. Combinations of these ranges are also possible (e.g., greater than or equal to 5 Pa and less than or equal to 90 Pa, greater than or equal to 20 Pa and less than or equal to 80 Pa, greater than or equal to 40 Pa and less than or equal to 60 Pa, or greater than or equal to 10 Pa and less than or equal to 40 Pa). It should be understood that the aforementioned ranges may refer to plasmas comprising any of the types of monomers described above, and that different pressures may be suitable for deposition of different layers, depending on the embodiment. Other ranges are also possible.

[0037] A plasma for depositing a layer (e.g., plasma 222 of FIG. 2) may have any of a variety of suitable powers. In some embodiments, a plasma for depositing a layer has a power of greater than or equal to 500 W, greater than or equal to 550 W, greater than or equal to 600 W, greater than or equal to 650 W, greater than or equal to 700 W, greater than or equal to 750 W, greater than or equal to 800 W, greater than or equal to 850 W, greater than or equal to 900 W, greater than or equal to 950 W, greater than or equal to 1000 W, greater than or equal to 1050 W, greater than or equal to 1100 W, greater than or equal to 1150 W, greater than or equal to 1200 W, greater than or equal to 1250 W, greater than or equal to 1300 W, greater than or equal to 1350 W, greater than or equal to 1400 W, or greater than or equal to 1450 W. In some embodiments, a plasma for depositing a layer has a power of less than or equal to 1500 W, less than or equal to 1450 W, less than or equal to 1400 W, less than or equal to 1350 W, less than or equal to 1300 W, less than or equal to 1250 W, less than or equal to 1200 W, less than or equal to 1150 W, less than or equal to 1100 W, less than or equal to 1050 W, less than or equal to 1000 W, less than or equal to 950 W, less than or equal to 900 W, less than or equal to 850 W, less than or equal to 800 W, less than or equal to 750 W, less than or equal to 700 W, less than or equal to 650 W, less than or equal to 600 W, or less than or equal to 550 W. Combinations of these ranges are also possible (e.g., greater than or equal to 500 W and less than or equal to 1500 W, greater than or equal to 500 W and less than or equal to 1000 W, or greater than or equal to 700 W and less than or equal to 950 W). Other ranges are also possible.

[0038] A layer positioned on top of on top of a plurality of nanostructures on a substrate may have any of a variety of appropriate compositions. In some embodiments, a layer formed on top of a plurality of nanostructures is or comprises a polymerized silane. In some embodiments, a layer formed on top of a plurality of nanostructures is or comprises a polymerized siloxane. A layer comprising a polymerized silane and/or a polymerized siloxane (e.g., a layer that is a polymerized silane or a layer that is a polymerized siloxane) may have advantages for repelling oil and/or water from the article. However, it should be understood that a layer positioned on top of a plurality of nanostructures may comprise or be an organic polymer. The material of a layer positioned on top of a plurality of nanostructures may have a uniform composition, or may have a concentration gradient as discussed in greater detail below.

[0039] In some embodiments, a layer covers at least a portion of a plurality of nanostructures positioned on a surface of a substrate. In some embodiments, an article comprises a layer that covers greater than or equal to 1%, greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 25%, greater than or equal to 50%, greater than or equal to 75%, greater than or equal to 90%, greater than or equal to 95%, or greater than or equal to 99% of a plurality of nanostructures positioned on a surface of a substrate. In some embodiments, an article comprises a layer that covers less than or equal to 100%, less than or equal to 99%, less than or equal to 95%, less than or equal to 90%, less than or equal to 75%, or less than or equal to 50% of a plurality of nanostructures positioned on a surface of a substrate. Combinations of these ranges are also possible (e.g., greater than or equal to 1% and less than or equal to 100%, greater than or equal to 25% and less than or equal to 100%, or greater than or equal to 50% and less than or equal to 100%). Other ranges are also possible.

[0040] A layer described herein may cover any of a variety of suitable portions of a surface of a substrate. In some embodiments, an article comprises a layer that covers greater than or equal to 1%, greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 25%, greater than or equal to 50%, greater than or equal to 75%, greater than or equal to 90%, greater than or equal to 95%, or greater than or equal to 99% of the area of a surface of the substrate. In some embodiments, an article comprises a layer that covers less than or equal to 100%, less than or equal to 99%, less than or equal to 95%, less than or equal to 90%, less than or equal to 75%, or less than or equal to 50% of the area of the surface of the substrate. Combinations of these ranges are also possible (e.g., greater than or equal to 1% and less than or equal to 100%, greater than or equal to 25% and less than or equal to 100%, or greater than or equal to 50% and less than or equal to 100%). Other ranges are also possible.

[0041] An article described herein may comprise a layer having any of a variety of suitable thicknesses. In some embodiments, an article comprises a layer having a thickness of greater than or equal to 4 nm, greater than or equal to 5 nm, greater than or equal to 6 nm, greater than or equal to 7 nm, greater than or equal to 8 nm, greater than or equal to 9 nm, greater than or equal to 10 nm, greater than or equal to 20 nm, greater than or equal to 30 nm, greater than or equal to 40 nm, greater than or equal to 50 nm, greater than or equal to 60 nm, greater than or equal to 70 nm, greater than or equal to 80 nm, greater than or equal to 90 nm, greater than or equal to 100 nm, greater than or equal to 120 nm, greater than or equal to 150 nm, greater than or equal to 180 nm, greater than or equal to 200 nm, greater than or equal to 220 nm, greater than or equal to 250 nm, greater than or equal to 280 nm, greater than or equal to 300 nm, greater than or equal to 500 nm, greater than or equal to 800 nm, greater than or equal to 1000 nm, greater than or equal to 1200 nm, greater than or equal to 1500 nm, greater than or equal to 1800 nm, greater than or equal to 2000 nm, greater than or equal to 3000 nm, greater than or equal to 4000 nm, or greater than or equal to 5000 nm. In some embodiments, an article comprises a layer having a thickness of less than or equal to 10000 nm, less than or equal to 8000 nm, less than or equal to 5000 nm, less than or equal to 4000 nm, less than or equal to 3000 nm, less than or equal to 2000 nm, less than or equal to 1800 nm, less than or equal to 1500 nm, less than or equal to 1200 nm, less than or equal to 1000 nm, less than or equal to 800 nm, less than or equal to 500 nm, less than or equal to 300 nm, less than or equal to 280 nm, less than or equal to 250 nm, less than or equal to 220 nm, less than or equal to 200 nm, less than or equal to 180 nm, less than or equal to 150 nm, less than or equal to 120 nm, less than or equal to 100 nm, less than or equal to 90 nm, less than or equal to 80 nm, less than or equal to 70 nm, less than or equal to 60 nm, less than or equal to 50 nm, less than or equal to 40 nm, less than or equal to 30 nm, less than or equal to 20 nm, less than or equal to 10 nm, less than or equal to 9 nm, less than or equal to 8 nm, or less than or equal to 7 nm. Combinations of these ranges are also possible (e.g., greater than or equal to 7 nm and less than or equal to 10000 nm, greater than or equal to 20 nm and less than or equal to 50 nm, greater than or equal to 20 nm and less than or equal to 40 nm, greater than or equal to 100 nm and less than or equal to 200 nm, or greater than or equal to 30 nm and less than or equal to 50 nm). Other ranges are also possible.

[0042] According to another aspect, a method of forming an article involving etching is provided. The method may comprise forming nanostructures by etching a layer formed on a surface of a substrate. FIG. 3 presents a schematic illustration of a nonlimiting method of article formation using such a bottom up approach. As shown in FIG. 3, a method may comprise a first step of forming a layer 333 on top of a substrate 301.

[0043] A layer suitable for etching may be formed by one or more methods described above. For example, layer 333 may be formed by exposing substrate 301 to a plasma 320 comprising a monomer (e.g., an organic monomer) at an appropriate pressure and power to form a uniform layer, as described above. In some embodiments, method comprises forming a layer that comprises or consists of an organic polymer on top of a substrate. Layer 333 may comprise a polymer. For example, layer 333 comprises an organic polymer polymerized from an organic monomer in plasma 320, according to some embodiments.

[0044] After the formation of a layer on top of a substrate, in some embodiments, the layer is etched to form an etched layer. An etched layer may comprise a plurality of nanostructures formed from the material of the layer. In some embodiments, etching is performed using a plasma. For example, referring again to the method of FIG. 3, a second method step 352 comprises forming an etched layer 337 comprising a plurality of nanostructures 335 by etching layer 333 using a second plasma 322.

[0045] Any of a variety of suitable plasmas may be used to etch a layer. In some embodiments, a plasma used for etching comprises a reactive species such as oxygen, argon, helium, neon, krypton, xenon, or combination thereof. A reactive species may, upon contacting a layer, etch the layer by reacting with a polymer of the layer. An etching process may result in the formation of a plurality of nanostructures by removing material between the nanostructures. An etched layer may have an increased oleophobicity and/or hydrophobicity relative to a similar smooth layer. An increased oleophobicity and/or hydrophobicity may result from the mechanism described above with reference to FIG. 1B, e.g., the presence of a gas between the nanostructures.

[0046] A plasma suitable for etching a layer may be used in a chamber having any of a variety of suitable pressures. In some embodiments, a layer is plasma-etched in a chamber having a pressure of greater than or equal to 10 Pa, greater than or equal to 15 Pa, greater than or equal to 20 Pa, greater than or equal to 25 Pa, greater than or equal to 30 Pa, greater than or equal to 35 Pa, greater than or equal to 40 Pa, greater than or equal to 45 Pa, greater than or equal to 50 Pa, greater than or equal to 55 Pa, greater than or equal to 60 Pa, greater than or equal to 65 Pa, greater than or equal to 70 Pa, greater than or equal to 75 Pa, greater than or equal to 80 Pa, greater than or equal to 85 Pa, greater than or equal to 90 Pa, or greater than or equal to 95 Pa. In some embodiments, a layer is plasma-etched in a chamber having a pressure of less than or equal to 100 Pa, less than or equal to 95 Pa, less than or equal to 90 Pa, less than or equal to 85 Pa, less than or equal to 80 Pa, less than or equal to 75 Pa, less than or equal to 70 Pa, less than or equal to 65 Pa, less than or equal to 60 Pa, less than or equal to 55 Pa, less than or equal to 50 Pa, less than or equal to 45 Pa, less than or equal to 40 Pa, less than or equal to 35 Pa, less than or equal to 30 Pa, less than or equal to 25 Pa, less than or equal to 20 Pa, or less than or equal to 15 Pa. Combinations of these ranges are also possible (e.g., greater than or equal to 10 Pa and less than or equal to 100 Pa, greater than or equal to 20 Pa and less than or equal to 80 Pa, or greater than or equal to 40 Pa and less than or equal to 80 Pa). Other ranges are also possible.

[0047] A plasma for etching a layer may have any of a variety of suitable powers. In some embodiments, a layer is etched using a plasma having a power of greater than or equal to 400 W, greater than or equal to 450 W, greater than or equal to 500 W, greater than or equal to 550 W, greater than or equal to 600 W, greater than or equal to 650 W, greater than or equal to 700 W, greater than or equal to 750 W, greater than or equal to 800 W, greater than or equal to 850 W, greater than or equal to 900 W, greater than or equal to 950 W, greater than or equal to 1000 W, or greater than or equal to 1050 W. In some embodiments, a layer is etched using a plasma having a power of less than or equal to 1100 W, less than or equal to 1050 W, less than or equal to 1000 W, less than or equal to 950 W, less than or equal to 900 W, less than or equal to 850 W, less than or equal to 800 W, less than or equal to 750 W, less than or equal to 700 W, less than or equal to 650 W, less than or equal to 600 W, less than or equal to 550 W, less than or equal to 500 W, or less than or equal to 450 W. Combinations of these ranges are also possible (e.g., greater than or equal to 400 W and less than or equal to 1100 W or greater than or equal to 500 W and less than or equal to 1000 W). Other ranges are also possible.

[0048] Using a plasma to etch a uniform layer to form nanostructures may present a number of technical challenges on certain substrates. For example, in some embodiments it is desirable for a plasma to etch different portions of a layer at different rates (e.g., in order to form nanostructures). In some embodiments, a method described herein involves heterogeneous etching of a layer (i.e., the formation of heterogeneous nanostructures on the layer). Heterogeneous etching of a layer may be performed using an electrode (e.g., involving a sputtering process). This technique may have advantages for the formation of nanostructures on textile substrates.

[0049] In some embodiments, an electrode is placed proximate a substrate during etching. An electrode may be situated such that a plasma may be used to sputter material from the electrode onto a surface of a substrate. For example, an electrode may be situated on a side of a substrate opposite a plasma, such that the plasma contacts both the substrate and the electrode. In some embodiments, at least a portion of an electrode extends beyond an edge of a substrate. An electrode may have a wider area than a substrate, or may be situated such that the electrode is offset from the substrate. In some embodiments, an electrode is a metal electrode. For example, an electrode may be or comprise aluminum, copper, and/or iron. In some embodiments, the electrode is aluminum, copper, or stainless steel. The electrode may have a charge that opposes a charge of a plasma used for etching, in some embodiments.

[0050] Material from an electrode may be sputtered onto a surface of a substrate (e.g., onto a surface that is opposite the electrode). A sputtered material may have the form of nanoparticles (e.g., metal nanoparticles). In some embodiments, a material is sputtered from an exposed portion of an electrode (e.g., a portion of an electrode that is directly exposed to a plasma). In some embodiments, nanoparticles sputtered onto a surface of an electrode may result in the formation of nanostructures. Nanostructures may form for any of a variety of appropriate reasons. Without wishing to be bound by any particular theory, charged nanoparticles may repel an etching plasma, reducing local etching. Again without wishing to be bound by any particular theory, nanoparticles may act as nucleation sites around which nanostructures may develop. In some embodiments nanostructures form through other mechanisms, or through a variety of mechanisms acting in combination.

[0051] An electrode described herein may be separated from a substrate by any of a variety of appropriate distances during etching. In some embodiments, during etching, an electrode and a substrate are separated by a distance of greater than or equal to 0.005 mm, greater than or equal to 0.01 mm, greater than or equal to 0.02 mm, greater than or equal to 0.05 mm, greater than or equal to 0.08 mm, greater than or equal to 0.1 mm, greater than or equal to 0.2 mm, greater than or equal to 0.5 mm, or greater than or equal to 0.8 mm. In some embodiments, during etching, an electrode and a substrate are separated by a distance of less than or equal to 1 mm, less than or equal to 0.8 mm, less than or equal to 0.5 mm, less than or equal to 0.2 mm, less than or equal to 0.1 mm, less than or equal to 0.08 mm, less than or equal to 0.05 mm, less than or equal to 0.02 mm, less than or equal to 0.01 mm, less than or equal to 0.008 mm, less than or equal to 0.005 mm, or less than or equal to 0.002 mm. Combinations of these ranges are also possible (e.g., greater than or equal to 0.001 mm and less than or equal to 1 mm). Other ranges are also possible.

[0052] In some embodiments a method comprises depositing a second layer of material that is at least partially positioned on an etched layer. Referring again to FIG. 3, a non-limiting method step 354 comprises depositing a second layer 313 on top of first, etched layer 337. A second layer may be deposited by any of a variety of methods, including any of the methods described herein. For example, as shown in FIG. 3, second layer 313 may be deposited using a plasma 324 analogous to plasma 222 used to deposit layer 213 as illustrated in FIG. 2. A second layer may have any of a variety of suitable compositions and properties, including any of the compositions and properties described herein. For example, in some embodiments, a second layer is or comprises a polymerized silane or a polymerized siloxane.

[0053] A second layer may cover any of a variety of suitable portions of an etched layer. In some embodiments, an article comprises a layer that covers greater than or equal to 1%, greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 25%, greater than or equal to 50%, greater than or equal to 75%, greater than or equal to 90%, greater than or equal to 95%, or greater than or equal to 99% of the area of an etched layer. In some embodiments, an article comprises a layer that covers less than or equal to 100%, less than or equal to 99%, less than or equal to 95%, less than or equal to 90%, less than or equal to 75%, or less than or equal to 50% of the area of an etched layer. Combinations of these ranges are also possible (e.g., greater than or equal to 1% and less than or equal to 100%, greater than or equal to 25% and less than or equal to 100%, or greater than or equal to 50% and less than or equal to 100%). Other ranges are also possible.

[0054] In yet another aspect, a method of forming an article comprising a gradient is provided. The gradient may include, for example, a mixture of two different types of polymers. In some embodiments, a method of forming an article comprises forming a layer comprising at least two components selected from the group of: a polymerized silane, a polymerized siloxane, and a polymer (e.g., an organic polymer). A layer comprising a composition gradient between at least two components selected from the group of: a polymerized silane, a polymerized siloxane, and a polymer may be formed by plasma deposition. Without wishing to be bound by any particular theory, in some embodiments, a layer may be deposited using a multicomponent plasma. For example, a layer may be deposited using a plasma comprising at least two components selected from the group of a siloxane, a silane, and a monomer that is not a silane or siloxane (e.g., an organic monomer). It is advantageous, according to some embodiments, to include an organic polymer in a layer comprising a concentration gradient.

[0055] Without wishing to bound by any particular theory, in some embodiments a composition gradient within a layer may be created by controlling a relative amount of each monomer of the plasma. In some embodiments, a ratio between a relative amount of each plasma component is varied continuously, producing a continuous concentration gradient in a layer. In some embodiments, a ratio between a relative amount of each plasma component is varied discontinuously, in a plurality of steps, but a continuous concentration gradient still arises. Without wishing to be bound by any particular theory, a continuous concentration gradient may arise from discontinuous changes in plasma composition as a result of surface effects, monomer diffusion within a layer, or by any of a variety of other mechanisms.

[0056] A layer comprising a composition gradient may be produced using any of a variety of appropriate plasmas. In some embodiments, a composition gradient is produced using a plasma comprising: at least one organic monomer selected from the group consisting of: ethylene, butadiene acetylene, methane, methanol, and ethanol; and at least one silane selected from the group consisting of tetramethylorthosilicate, tetraethylorthosilicate, hexadecyltrimethoxysilane, and vinyltrimethylsilane. According to some embodiments, a composition gradient is produced using a plasma comprising: at least one organic monomer selected from the group consisting of: ethylene, butadiene acetylene, methane, methanol, and ethanol; and at least one siloxane selected from the group consisting of hexadecyltrimethoxysilane, and hexaethyldisiloxane. In some embodiments, a composition gradient is produced using a plasma comprising: at least one organic monomer selected from the group consisting of ethylene, butadiene acetylene, methane, methanol, and ethanol: at least one silane selected from the group consisting of tetramethylorthosilicate, tetraethylorthosilicate, hexadecyltrimethoxysilane, and vinyltrimethylsilane; and at least one siloxane selected from the group consisting of hexadecyltrimethoxysilane, and hexaethyldisiloxane. It should, of course, be understood that concentration gradient may be produced using plasmas comprising more than two monomers, and/or comprising monomers not listed above.

[0057] A plasma used to deposit a layer comprising a composition gradient may have any of a variety of appropriate powers and pressures, including the powers and pressures described in the context of layer deposition, above. In some embodiments, plasmas with pressures of greater than or equal to 20 Pa and less than or equal to 60 Pa have been found to be advantageous for depositing layers with composition gradients. In some embodiments, plasmas with powers of greater than or equal to 700 W and less than or equal to 1000 W have been found to be advantageous for depositing layers with composition gradients.

[0058] A first layer comprising a composition gradient and a second layer comprising a composition gradient may each independently be formed on a substrate by a method of layer formation described above. In some embodiments, a first layer is between a second layer and a substrate.

[0059] In the context of the present disclosure, it has been recognized that articles comprising multiple layers with composition gradients may have favorable elastic, water repellent, and/or oil repellent properties. Without wishing to be bound by any particular theory, composition gradients of layers on a substrate may preserve desirable surface properties (e.g., high hydrophobicity and/or oleophobicity) while preserving mechanical compatibility between the layers and the substrate. A first layer and a second layer may have the same or different compositions. A first layer and a second layer may have a same or different composition gradients. In some embodiments, it may be advantageous for one or more layers on a substrate to have a polymerize silane and/or or a polymerized siloxane concentration that increases with distance away from the substrate (e.g., across a thickness of the layer(s)). In some embodiments, it may be advantageous for one or more layers on a substrate to have an organic polymer concentration that decreases with distance away from the substrate (e.g., across a thickness of the layer(s)).

[0060] A layer comprising a composition gradient may be etched, but the disclosure is not limited to layers that have been etched. Similarly, a layer comprising a composition gradient may be deposited on top of a plurality of nanostructures, but the disclosure is not limited to layers that have been deposited on a plurality of nanostructures.

[0061] An article formed as described herein may repel oil and/or water. Without wishing to be bound by any particular theory, the ability of an article to repel oil and/or water may be related to a surface energy of a surface of the article. However, the present disclosure recognizes that, according to some embodiments, surface features (e.g., nanostructures or layers deposited thereon) may advantageously improve the ability of a substrate to repel oil and/or water. Such improvements in oil and/or water repellency may result from trapping of air between nanostructures, which may reduce the ability of liquids like oil and water to wet a surface of an article, however other mechanisms are also possible. Oil and/or water repellency may be desirable for a number of applications, particularly in the context of articles comprising textiles. For example, an article comprising a textile or fabric described herein may be used in a garment (e.g., jacket, a glove, a shoe), a shelter (e.g., a tent, an awning), a covering (e.g., an umbrella), a mask (e.g., facemask) or any of a number of other suitable contexts where oil and/or water repellency may be desirable.

[0062] In some embodiments, an article described herein is hydrophobic. A hydrophobic article comprises at least one hydrophobic surface. Generally, water contacting a hydrophobic surface of a hydrophobic article has a contact angle. An article described herein may have any of a variety of suitable contact angles with water. In some embodiments, an article has a water contact angle of greater than or equal to 90, greater than or equal to 95, greater than or equal to 100, greater than or equal to 105, greater than or equal to 110, greater than or equal to 115, greater than or equal to 120, greater than or equal to 125, greater than or equal to 130, greater than or equal to 135, greater than or equal to 140, greater than or equal to 145, greater than or equal to 150, greater than or equal to 155, greater than or equal to 160, greater than or equal to 165, greater than or equal to 170, greater than or equal to 175, or greater. In some embodiments, an article has a water contact angle of less than or equal to 180, less than or equal to 175, less than or equal to 170, less than or equal to 165, less than or equal to 160, less than or equal to 155, less than or equal to 150, less than or equal to 145, less than or equal to 130, less than or equal to 125, less than or equal to 120, less than or equal to 115, less than or equal to 110, less than or equal to 105, less than or equal to 100, or less than or equal to 95. Combinations of these ranges are also possible (e.g., greater than or equal to 90 and less than or equal to 180, greater than or equal to 120 and less than or equal to 180, or greater than or equal to 140 and less than or equal to) 180. Other ranges are also possible.

[0063] According to some embodiments some embodiments, hydrophobicity of an article is characterized by its hydrophobicity rank. In some embodiments, an article has a hydrophobicity rank of greater than or equal to 1, greater than or equal to 2, greater than or equal to 3, greater than or equal to 4, greater than or equal to 5, greater than or equal to 6, or greater than or equal to 7. In some embodiments, an article has a hydrophobicity rank of less than or equal to 8, less than or equal to 7, less than or equal to 6, less than or equal to 5, less than or equal to 4, less than or equal to 3, or less than or equal to 2. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 1 and less than or equal to 8, greater than or equal to 1 and less than or equal to 5, or greater than or equal to 1 and less than or equal to 3). Other ranges are also possible. In some embodiments, an article is not hydrophobic and has a hydrophobicity rank of 0.

[0064] Hydrophobicity rank as described herein is determined according to AATCC TM 193-2017 measured after conditioning for 4 hours at 212 C. and 655% relative humidity (RH). Briefly, a set of 8 test solutions comprising different volumetric ratios of water and isopropanol are used. 3 drops of each test solution (having an average volume of about 0.05 mL) are dropped on an article from a height of about 0.6 cm above the article. The test solution having the highest proportion of isopropanol that does not wet the article (by forming a contact angle of less than or equal to 75 with the article) within 10 seconds corresponds to the hydrophobicity rank. For example, if a test solution with a 60:40 water:isopropyl alcohol (vol:vol) with a surface tension of 25.4 mN/m does not wet the article within 10 seconds, but a test solution with a 50:50 water:isopropyl alcohol (vol:vol) with a surface tension of 24.5 mN/m wets the article within 10 seconds, then the article has a hydrophobicity rank of 6.

[0065] An article may be oleophobic. Generally, an oleophobic article comprises at least one oleophobic surface. The oleophobicity of the article may be characterized by an oleophobicity rank of the article. An article described herein may have any of a variety of suitable oleophobicity ranks. In some embodiments, an article has an oleophobicity rank of greater than or equal to 1, greater than or equal to 2, greater than or equal to 3, greater than or equal to 4, greater than or equal to 4.5, greater than or equal to 5, greater than or equal to 5.5, greater than or equal to 6, greater than or equal to 6.5, greater than or equal to 7, or greater than or equal to 7.5. In some embodiments, an article has an oleophobicity rank of less than or equal to 8, less than or equal to 7.5, less than or equal to 7, less than or equal to 6.5, less than or equal to 6, less than or equal to 5.5, less than or equal to 5, less than or equal to 4.5, less than or equal to 4, less than or equal to 3, or less than or equal to 2. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 1 and less than or equal to 8, greater than or equal to 1 and less than or equal to 5, or greater than or equal to 1 and less than or equal to 3). Other ranges are also possible. In some embodiments, an article described herein is not oleophobic and has an oleophobicity rank of 0.

[0066] Oleophobicity rank as described herein is determined according to AATCC TM 118-2017 measured at after conditioning for 4 hours at 212 C. and 655% relative humidity (RH). Briefly, 5 drops of each test oil (having an average droplet diameter of about 2 mm) are placed on five different locations on the article. The test oil with the greatest oil surface tension that does not wet a surface of the article (e.g., has a contact angle greater than or equal to 90 degrees with the surface of the article) after 30 seconds of contact with the article corresponds to the oleophobicity rank. For example, if a test oil with a surface tension of 26.6 mN/m does not wet the article after 30 seconds, but a test oil with a surface tension of 25.4 mN/m wets the surface of article within thirty seconds, the article has an oleophobicity rank of 4. In some embodiments, if three of more of the five drops partially wet the surface (e.g., by forming a droplet, but not a well-rounded drop on the surface) in a given test, then the oleophobicity rank is expressed to the nearest 0.5 value determined by subtracting 0.5 from the number of the test liquid. By way of example, if a test oil with a surface tension of 25.4 mN/m does not wet the surface of an article after 30 seconds, but a test oil with a surface tension of 23.8 mN/m only partially wets the surface of the article after 30 seconds (e.g., three or more of the test droplets form droplets on the surface of the article that are not well-rounded droplets) within thirty seconds, the article has an oleophobicity rank of 5.5.

[0067] In some embodiments, the hydrophobicity ranks and/or the olcophobicity ranks described above refer to the hydrophobicity rank and/or the olcophobicity rank of an unwashed article. In some embodiments, oleophobic and/or hydrophobic articles that are capable of remaining oleophobic and/or hydrophobic after washing are desirable. For example, and article comprising a textile substrate may be particularly useful if able to retain oleophobic and/or hydrophobic properties after washing.

[0068] An article described herein may have an oleophobicity rank and/or a hydrophobicity rank described above after being subjected to any of a variety of suitable numbers of standard wash cycles. For example, in some embodiments an article has an oleophobicity rank and/or a hydrophobicity rank described above after being subjected to a number of standard wash cycles greater than or equal to 1, greater than or equal to 2, greater than or equal to 3, greater than or equal to 4, greater than or equal to 5, greater than or equal to 6, greater than or equal to 7, greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, greater than or equal to 11, greater than or equal to 12, greater than or equal to 13, greater than or equal to 14, or greater than or equal to 15. In some embodiments an article has an oleophobicity rank and/or a hydrophobicity rank described above after being subjected to a number of standard wash cycles less than or equal to 20, less than or equal to 19, less than or equal to 18, less than or equal to 17, less than or equal to 16, less than or equal to 15, less than or equal to 14, less than or equal to 13, less than or equal to 12, less than or equal to 11, less than or equal to 10, less than or equal to 9, less than or equal to 8, less than or equal to 7, less than or equal to 6, or less than or equal to 5. In some embodiments, an article has an oleophobicity rank and/or a hydrophobicity rank described above after being subjected to 0 standard wash cycles. Combinations of these ranges are also possible (e.g., greater than or equal to 1 and less than or equal to 20, greater than or equal to 5 and less than or equal to 15, or greater than or equal to 10 and less than or equal to 15). These ranges may further be combined with any of the forgoing ranges (e.g., an article may have a hydrophobicity rank of greater than or equal to 2 and less than or equal to 4 after being subjected to a number of wash cycles greater than or equal to 10 and less than or equal to 15, an article may have an oleophobicity rank of greater than or equal to 1 and less than or equal to 3 after being subjected to a number of wash cycles greater than or equal to 10 and less than or equal to 15). Other ranges are also possible. Standard wash cycles may be carried out using the ISO 6003:2012 (E) standard protocol.

[0069] Commercially, fluorinated polymers are often used to produce oleophobic and/or hydrophobic articles. However, the use of fluorinated polymers is not environmentally friendly. One advantage of the methods and articles described herein is that they may provide oleophobic and/or hydrophobic surfaces using nanostructures and/or layers without fluorine, or with only trace amounts of fluorine.

[0070] In some embodiments, an article described herein comprises a plurality of nanostructures that comprises less than or equal to 0.5 at %, less than or equal to 0.4 at %, less than or equal to 0.3 at %, less than or equal to 0.2 at %, less than or equal to 0.1 at %, less than or equal to 0.08 at %, less than or equal to 0.05 at %, less than or equal to 0.02 at %, less than or equal to 0.01 at %, less than or equal to 0.008 at %, less than or equal to 0.005 at %, or less than or equal to 0.002 at % fluorine atoms. In some embodiments, an article described herein comprises a plurality of nanostructures that comprises greater than or equal to 0 at %, or greater than or equal to 0.001 at % fluorine atoms. Combinations of these ranges are also possible (e.g., greater than or equal to 0 at % and less than or equal to 0.5 at % or greater than or equal to 0 at % and less than or equal to 0.1 at %). Other ranges are also possible.

[0071] In some embodiments, an article described herein comprises a layer that comprises less than or equal to 0.5 at %, less than or equal to 0.4 at %, less than or equal to 0.3 at %, less than or equal to 0.2 at %, less than or equal to 0.1 at %, less than or equal to 0.08 at %, less than or equal to 0.05 at %, less than or equal to 0.02 at %, less than or equal to 0.01 at %, less than or equal to 0.008 at %, less than or equal to 0.005 at %, or less than or equal to 0.002 at % fluorine atoms. In some embodiments, an article described herein comprises a layer that comprises greater than or equal to 0 at %, or greater than or equal to 0.001 at % fluorine atoms. Combinations of these ranges are also possible (e.g., greater than or equal to 0 at % and less than or equal to 0.5 at % or greater than or equal to 0 at % and less than or equal to 0.1 at %). Other ranges are also possible.

[0072] In some embodiments, the entire article has an amount of fluorine atoms in one or more of the above-referenced ranges.

[0073] In some embodiments, an article described herein comprises a substrate. A substrate may be a homogeneous, solid substrate. For example a substrate may be a piece of glass, silicon, or metal. In some embodiments, the substrate is flexible.

[0074] According to some embodiments, a substrate is a textile. For example, a substrate may comprise a woven web or a nonwoven web. In some embodiments, the textile comprises a plurality of fibers. A plurality of fibers may be entangled (e.g., by weaving). The fibers may be continuous fibers or non-continuous fibers. In some embodiments at least some of (e.g., all of) a plurality of fibers of a textile are polymeric fibers. For example, a plurality of fibers may comprise a polyaramid (e.g., poly(meta-aramid), commercially known as Nomex; poly(para-aramid), commercially known as Kevlar), nylon, cotton, polyester, copolyamides, PET, PLA, PLGA, PVDF, cellulose, poly(ethylene-co-vinyl acetate), polyurethane, polyvinylchloride, or combinations thereof. In some embodiments, at least some of (e.g., all of) a plurality of fibers described herein comprises glass fibers. In some embodiments, a plurality of fibers comprises a mixture of fibers with different compositions (e.g., a mixture of Nomex fibers and cotton fibers, or a mixture of cotton fibers and glass fibers). In some embodiments, a plurality of fibers comprises fibers with uniform compositions that are blends or copolymers of two or more polymers.

[0075] Although in some embodiments textile substrates may be particularly useful, there are no particular limitations on the material of the substrate and any of a variety of suitable materials may be used. In some embodiments, a substrate includes one or more coatings prior to being processed using a method described herein. As discussed above, in some embodiments, an article comprises a plurality of nanostructures deposited on the substrate or a coating of a substrate, as discussed above. The substrate (and/or coating) and a plurality of nanostructures may have different compositions, in some embodiments. For example, the nanostructures may be formed from a relatively more hydrophobic material than a substrate, or a coating on substrate, in some embodiments.

[0076] An article described herein may comprise one or more layers, as discussed above. In some embodiments, an article comprises a layer positioned on a surface of a substrate. A layer may directly contact a substrate, or may be separated by one or more intervening layers. In some embodiments, a layer is positioned on a plurality of nanostructures (e.g., on a surface of a substrate). For example, a layer may be positioned on a plurality of nanostructures, such that the layer directly contacts the nanostructures of the plurality and the surface of the substrate.

[0077] In some embodiments, more than one layer is positioned on a surface of a substrate (e.g., a textile). For example, an article may comprise a first layer positioned on a surface of a substrate and a second layer positioned on the first layer. In some embodiments, at least a portion of the first layer is positioned between the second layer and the surface of the substrate.

[0078] In articles with one or more layers positioned on a surface of a substrate, the present disclosure recognizes that it may be advantageous to preserve certain relationships between mechanical properties of the layer(s) and mechanical properties of the substrate. For example, when a layer of an article has clastic properties relatively similar to elastic properties of a substrate (e.g., a textile) of the article upon which the layer is positioned, the layers may provide longer-lasting oleophobicity and/or hydrophobicity, improved wear resistance, or improved wash resistance. Controlling the mechanical properties of a layer while preserving desirable oleophobicity and/or hydrophobicity of the layer may present certain challenges, particularly where oleophobicity and/or hydrophobicity result exclusively from the composition of the layer. However, the present disclosure recognizes that the use of nanostructures and/or composition gradients within layers may allow control of the elastic properties of layers while retaining oleophobicity and/or hydrophobicity of the article.

[0079] A substrate described herein may have any suitable elastic modulus. In some embodiments, a substrate has an elastic modulus of greater than or equal to 20 kPa, greater than or equal to 40 kPa, greater than or equal to 60 kPa, greater than or equal to 80 kPa, greater than or equal to 100 kPa, greater than or equal to 200 kPa, greater than or equal to 500 kPa, greater than or equal to 1 MPa, greater than or equal to 2 MPa, greater than or equal to 5 MPa, greater than or equal to 10 MPa, greater than or equal to 50 MPa, greater than or equal to 100 MPa, greater than or equal to 200 MPa, greater than or equal to 500 MPa, greater than or equal to 1 GPa, or greater than or equal to 2 GPa. In some embodiments, a substrate has an elastic modulus of less than or equal to 5 GPa, less than or equal to 2 GPa, less than or equal to 1 GPa, less than or equal to 500 MPa, less than or equal to 200 MPa, less than or equal to 100 MPa, less than or equal to 50 MPa, less than or equal to 20 MPa, less than or equal to 10 MPa, less than or equal to 5 MPa, less than or equal to 2 MPa, less than or equal to 1 MPa, less than or equal to 500 kPa, less than or equal to 200 kPa, less than or equal to 100 kPa, less than or equal to 80 kPa, less than or equal to 60 kPa, or less than or equal to 40 kPa. Combinations of these ranges are also possible (e.g., greater than or equal to 20 kPa and less than or equal to 5 GPa, or greater than or equal to 20 kPa and less than or equal to 80 kPa). Other ranges are also possible.

[0080] The elastic modulus of a substrate or a layer may be determined by nanoindentation followed by Oliver-Pharr analysis. Nanoindentation may be performed using a Nanovea indentation tester used to indent a substrate or a layers using a Berkovich indenter tip, prior to Oliver-Pharr analysis. The indenter may have a contact load of 0.01-0.1 mN and a maximum load of 0.1-1 mN, such that the nanoindenter reaches a depth of less than or equal to 10% of the thickness of the substrate or the layer.

[0081] An article herein may comprise a layer (e.g., a plasma-deposited layer) having any suitable elastic moduli. In some embodiments, an article comprises a layer (e.g., a plasma-deposited layer) with an elastic modulus of greater than or equal to 0.05 GPa, greater than or equal to 0.1 GPa, greater than or equal to 0.2 GPa, greater than or equal to 0.3 GPa, greater than or equal to 0.4 GPa, greater than or equal to 0.5 GPa, greater than or equal to 0.6 GPa, greater than or equal to 0.7 GPa, greater than or equal to 0.8 GPa, greater than or equal to 0.9 GPa, greater than or equal to 1 GPa, greater than or equal to 2 GPa, greater than or equal to 3 GPa, greater than or equal to 4 GPa, greater than or equal to 5 GPa, greater than or equal to 6 GPa, greater than or equal to 7 GPa, greater than or equal to 8 GPa, greater than or equal to 9 GPa, greater than or equal to 10 GPa, greater than or equal to 11 GPa, greater than or equal to 12 GPa, greater than or equal to 13 GPa, or greater than or equal to 14 GPa. In some embodiments, an article comprises a layer with an elastic modulus of less than or equal to 15 GPa, less than or equal to 14 GPa, less than or equal to 13 GPa, less than or equal to 12 GPa, less than or equal to 11 GPa, less than or equal to 10 GPa, less than or equal to 9 GPa, less than or equal to 8 GPa, less than or equal to 7 GPa, less than or equal to 6 GPa, less than or equal to 5 GPa, less than or equal to 4 GPa, less than or equal to 3 GPa, less than or equal to 2 GPa, less than or equal to 1 GPa, less than or equal to 0.9 GPa, less than or equal to 0.8 GPa, less than or equal to 0.7 GPa, less than or equal to 0.6 GPa, less than or equal to 0.5 GPa, less than or equal to 0.4 GPa, less than or equal to 0.3 GPa, less than or equal to 0.2 GPa, less than or equal to 0.1 GPa, or less than or equal to 0.05 GPa. Combinations of these ranges are also possible (e.g., greater than or equal to 0.05 GPa and less than or equal to 15 GPa, greater than or equal to 0.1 GPa and less than or equal to 0.05 GPa, greater than or equal to 1 GPa and less than or equal to 5 GPa, greater than or equal to 4 GPa and less than or equal to 12 GPa, greater than or equal to 0.5 GPa and less than or equal to 2 GPa, greater than or equal to 0.3 GPa and less than or equal to 0.8 GPa, greater than or equal to 0.1 GPa and less than or equal to 0.6 GPa, or greater than or equal to 0.5 GPa and less than or equal to 2 GPa). Other ranges are also possible. It should be understood that an article may comprise more than one layer having a modulus within a range described above.

[0082] In some embodiments, an article comprises a layer (e.g., a plasma-deposited layer) and a substrate, wherein the ratio of the elastic modulus of the layer to the elastic modulus of the substrate is greater than or equal to 110.sup.3, greater than or equal to 210.sup.3, greater than or equal to 510.sup.3, greater than or equal to 810.sup.3, greater than or equal to 110.sup.4, greater than or equal to 210.sup.3, greater than or equal to 510.sup.3, greater than or equal to 810.sup.3, greater than or equal to 110.sup.4, greater than or equal to 210.sup.4, greater than or equal to 510.sup.4, greater than or equal to 810.sup.4, greater than or equal to 110.sup.5, greater than or equal to 210.sup.5, greater than or equal to 510.sup.5, greater than or equal to 810.sup.5, or greater than or equal to 110.sup.6. In some embodiments, an article comprises a layer (e.g., a plasma-deposited layer) and a substrate, wherein the ratio of the elastic modulus of the layer to the elastic modulus of the substrate is less than or equal to 210.sup.6, less than or equal to 110.sup.6, less than or equal to 810.sup.5, less than or equal to 510.sup.5, less than or equal to 210.sup.5, less than or equal to 110.sup.5, less than or equal to 810.sup.4, less than or equal to 510.sup.4, less than or equal to 210.sup.4, less than or equal to 110.sup.4, less than or equal to 810.sup.3, less than or equal to 510.sup.3, or less than or equal to 210.sup.3. Combinations of these ranges are also possible (e.g., greater than or equal to 110.sup.3 and less than or equal to 110.sup.6, greater than or equal to 110.sup.3 and less than or equal to 510.sup.5, or greater than or equal to 110.sup.4 and less than or equal to 110.sup.6). Other ranges are also possible. In some embodiments, an article comprises a substrate having a first elastic modulus, a first layer having a second elastic modulus, and a second layer having a third elastic modulus, wherein a ratio of the second elastic modulus to the first elastic modulus and a ratio of the third elastic modulus to the first elastic modulus each independently fall within one of these ranges described herein.

[0083] An article described herein may comprise a plurality of nanostructures. The nanostructures may be formed by any of a variety of suitable methods, including those described herein. In some embodiments, the plurality of nanostructures is discrete. For example, a first nanostructure of a plurality of nanostructures may have no direct contact with a second nanostructure of the plurality of nanostructures. Discrete nanostructures may be formed by plasma deposition of the nanostructures, as described in greater detail above. However, in some embodiments, the plurality of nanostructures is not discrete. For example, the nanostructures of the plurality may be in direct contact with one another (e.g., at bases of the nanostructures). Nanostructures in direct contact with one another may be formed, according to some embodiments, by etching a layer to form a plurality of nanostructures, such that nanostructures are separated from one another by an etched groove and are physically joined at a base of the groove.

[0084] The nanostructures may have any of a variety of suitable geometries. For example, in some embodiments, a nanostructure is relatively round and has a relatively uniform diameter. However, the nanostructures may be elongated or have other geometries, and the disclosure is not so limited.

[0085] In some embodiments, the nanostructures increase the roughness of an article. An article described herein may comprise a surface having any of a variety of suitable root mean squared (RMS) roughness values. In some embodiments, an article described herein comprises a surface having a roughness of greater than or equal to 0.05 microns, greater than or equal to 0.1 microns, greater than or equal to 0.2 microns, greater than or equal to 0.3 microns, greater than or equal to 0.4 microns, greater than or equal to 0.5 microns, greater than or equal to 0.6 microns, greater than or equal to 0.7 microns, greater than or equal to 0.8 microns, greater than or equal to 0.9 microns, greater than or equal to 0.10 microns, greater than or equal to 0.11 microns, or greater than or equal to 0.12 microns, greater than or equal to 0.13 microns, greater than or equal to 0.14 microns, greater than or equal to 0.15 microns, or greater than or equal to 0.2 microns. In some embodiments, an article described herein comprises a surface having a roughness of less than or equal to 0.2 microns, less than or equal to 0.15 microns, less than or equal to 0.14 microns, less than or equal to 0.13 microns, less than or equal to 0.12 microns, less than or equal to 0.11 microns, less than or equal to 0.10 microns, less than or equal to 0.9 microns, less than or equal to 0.8 microns, less than or equal to 0.7 microns, less than or equal to 0.6 microns, less than or equal to 0.5 microns, less than or equal to 0.4 microns, less than or equal to 0.3 microns, less than or equal to 0.2 microns, or less than or equal to 0.1 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.05 microns and less than or equal to 0.2 microns). Other ranges are also possible. The RMS roughness of an article may be determined by atomic force microscopy.

[0086] An article described herein may comprise nanostructures having any of a variety of suitable diameters. In some embodiments, an article comprises a plurality of nanostructures having an average diameter of greater than or equal to 0.05 microns, greater than or equal to 0.08 microns, greater than or equal to 0.1 microns, greater than or equal to 0.12 microns, greater than or equal to 0.15 microns, greater than or equal to 0.18 microns, greater than or equal to 0.2 microns, greater than or equal to 0.05 microns, greater than or equal to 0.22 microns, greater than or equal to 0.25 microns, greater than or equal to 0.28 microns, greater than or equal to 0.3 microns, greater than or equal to 0.32 microns, greater than or equal to 0.35 microns, greater than or equal to 0.38 microns, greater than or equal to 0.4 microns, or greater than or equal to 0.42 microns. In some embodiments, an article comprises a plurality of nanostructures having an average diameter of less than or equal to 0.45 microns, less than or equal to 0.42 microns, less than or equal to 0.4 microns, less than or equal to 0.38 microns, less than or equal to 0.35 microns, less than or equal to 0.32 microns, less than or equal to 0.3 microns, less than or equal to 0.28 microns, less than or equal to 0.25 microns, less than or equal to 0.22 microns, less than or equal to 0.2 microns, less than or equal to 0.18 microns, less than or equal to 0.15 microns, less than or equal to 0.12 microns, or less than or equal to 0.1 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.05 microns and less than or equal to 0.45 microns, greater than or equal to 0.1 and less than or equal to 0.4 microns, or greater than or equal to 0.12 and less than or equal to 0.38). Other ranges are also possible. The nanostructure diameter may be determined by atomic force microscopy.

[0087] In some embodiments, an article comprises a plurality of nanostructures having an standard deviation in diameter of greater than or equal to 0.005 microns, greater than or equal to 0.008 microns, greater than or equal to 0.01 microns, greater than or equal to 0.012 microns, greater than or equal to 0.015 microns, greater than or equal to 0.018 microns, greater than or equal to 0.02 microns, greater than or equal to 0.022 microns, greater than or equal to 0.025 microns, greater than or equal to 0.028 microns, greater than or equal to 0.03 microns, or greater than or equal to 0.032 microns. In some embodiments, an article comprises a plurality of nanostructures having an standard deviation in diameter of less than or equal to 0.035 microns, less than or equal to 0.032 microns, less than or equal to 0.03 microns, less than or equal to 0.028 microns, less than or equal to 0.025 microns, less than or equal to 0.022 microns, less than or equal to 0.02 microns, less than or equal to 0.018 microns, less than or equal to 0.015 microns, less than or equal to 0.012 microns, less than or equal to 0.01 microns, or less than or equal to 0.008 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.005 microns and less than or equal to 0.035 microns, greater than or equal to 0.008 microns and less than or equal to 0.030 microns, or greater than or equal to 0.008 microns and less than or equal to 0.025 microns). Other ranges are also possible. The standard deviation in nanostructure diameter may be determined by atomic force microscopy.

[0088] An article described herein may comprise nanostructures having any of a variety of suitable aspect ratios of nanostructure height to nanostructure diameter. In some embodiments, an article comprises a plurality of nanostructures having an average aspect ratio of greater than or equal to 0.5, greater than or equal to 0.6, greater than or equal to 0.7, greater than or equal to 0.8, greater than or equal to 0.9, greater than or equal to 1, greater than or equal to 2, greater than or equal to 3, greater than or equal to 4, greater than or equal to 5, greater than or equal to 6, greater than or equal to 7, greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, greater than or equal to 11, or greater than or equal to 12. In some embodiments, an article comprises an average aspect ratio of less than or equal to 13, less than or equal to 12, less than or equal to 11, less than or equal to 10, less than or equal to 9, less than or equal to 8, less than or equal to 7, less than or equal to 6, less than or equal to 5, less than or equal to 4, less than or equal to 3, less than or equal to 2, less than or equal to 1, less than or equal to 0.9, less than or equal to 0.8, less than or equal to 0.7, or less than or equal to 0.6. Combinations of these ranges are also possible (e.g., greater than or equal to 0.5 and less than or equal to 13 or greater than or equal to 1 and less than or equal to 12). Other ranges are also possible. The aspect ratio of the nanostructures may be determined by atomic force microscopy.

[0089] A plurality of nanostructures may be disposed in any of a variety of suitable arrangements. For example, the nanostructures may be arranged in an ordered grid. In some embodiments, the nanostructures have a random arrangement. A random arrangement of nanostructures may be uniformly random, or may simply have a stochastic spatial distribution with high local concentrations of nanostructures in some areas and low local concentrations of nanostructures in others. One advantage of random arrangements of nanostructures may be scalability. For example, in some embodiments it is easier to fabricate random arrangements of nanostructures over large substrate areas. Thus, random arrangements of nanoparticles may have particular advantages for the use of nanostructures on textile substrates.

[0090] An article described herein may comprise nanostructures having any of a variety of suitable peak to peak spacings. In some embodiments, an article comprises a plurality of nanostructures having an average peak-to-peak spacing of greater than or equal to 0.2 microns, greater than or equal to 0.5 microns, greater than or equal to 0.8 microns, greater than or equal to 1 micron, greater than or equal to 1.2 microns, greater than or equal to 1.5 microns, greater than or equal to 1.8 microns, greater than or equal to 2 microns, or greater than or equal to 2.2 microns. In some embodiments, an article comprises a plurality of nanostructures having an average peak-to-peak spacing of less than or equal to 2.5 microns, less than or equal to 2.2 microns, less than or equal to 2 microns, less than or equal to 1.8 microns, less than or equal to 1.5 microns, less than or equal to 1.2 microns, less than or equal to 1 micron, less than or equal to 0.8 microns, less than or equal to 0.5 microns, or less than or equal to 0.2 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.2 microns and less than or equal to 2.5 microns or greater than or equal to 0.2 microns and less than or equal to 2.2 microns). Other ranges are also possible.

[0091] In some embodiments, an article comprises a plurality of nanostructures having a standard deviation in peak-to-peak spacing of greater than or equal to 0.001 microns, greater than or equal to 0.002 microns, greater than or equal to 0.005 microns, greater than or equal to 0.01 microns, greater than or equal to 0.02 microns, greater than or equal to 0.05 microns, greater than or equal to 0.08 microns, greater than or equal to 0.1 microns, greater than or equal to 0.2 microns, greater than or equal to 0.3 microns, or greater than or equal to 0.4 microns. In some embodiments, an article comprises a plurality of nanostructures having a standard deviation in peak-to-peak spacing of less than or equal to 0.5 microns, less than or equal to 0.4 microns, less than or equal to 0.3 microns, less than or equal to 0.2 microns, less than or equal to 0.1 microns, less than or equal to 0.08 microns, less than or equal to 0.05 microns, less than or equal to 0.02 microns, less than or equal to 0.01 microns, less than or equal to 0.008 microns, less than or equal to 0.005 microns, or less than or equal to 0.002 microns. Combinations of these ranges are also possible (e.g., greater than or equal to 0.001 microns and less than or equal to 0.5 microns). Other ranges are also possible.

[0092] The following examples are intended to illustrate certain embodiments of the present disclosure, but do not exemplify the full scope of the disclosure.

Example 1

[0093] This example demonstrates the formation of nanostructures on a surface of a silicon wafers (University Wafers) without etching, according to one, non-limiting embodiment. In this example, a butadiene (C.sub.4H.sub.6) plasma was used to produce a plurality of nanostructures on a silicon wafer. All plasmas were provided with microwave (MW) power. The samples were deposited using a variety of different deposition conditions summarized in Table 1. Table 1 provides flow rates, plasma power, plasma chamber pressure, and treatment duration for each plasma condition used to produce the nanostructures. In Table 1, the plasma conditions are provided for four samples, numbered sequentially as Sample 1, Sample 2, Sample 3, and Sample 4.

TABLE-US-00001 TABLE 1 Details of plasma processing conditions for nanostructure formation Plasma Flow Power Chamber Duration Sample (sccm) (W) Pressure (Pa) (seconds) 1 20 900 0.1 180 2 20 1100 0.1 150 3 20 900 10 300 4 20 1100 10 240

[0094] After deposition, profilimetry tests were carried out on each sample using a Bruker DektakXT instrument. Results of the profilometry are presented in FIGS. 4A-4D, which show cross-sectional profiles of the surface of Samples 1-4, respectively. FIGS. 5A-5D illustrate scanning electron micrographs of Samples 1-4, respectively, providing a qualitative illustration of the nanostructures formed. These results demonstrate the formation of nanostructures comprising plasma-polymerized polybutadiene on the surface of a substrate, according to some embodiments.

Example 2

[0095] This example demonstrates the fabrication and mechanical testing of article layers that have desirable elastic properties, according to some embodiments. The layers were generally formed by plasma deposition on silicon wafers (University Wafers), which allowed analysis of the elastic modulus of the layers. The elastic properties of samples were measured using Oliver Pharr method, and a Nanovea indentation tester used to indent the layers using a Berkovich indenter tip. Indentation data were fitted and results calculated using a code written in Matlab software.

[0096] Four non-limiting layers (Samples 5-8) were formed using plasmas comprising ethylene (C.sub.2H.sub.4) and hexamethyldisiloxane (HMDSO) under conditions described in Table 2. All plasmas were provided with microwave (MW) power. Generally, samples produced using plasmas with higher ethylene flows had increased elastic modulus, as shown in Table 2. The increased modulus associated with higher ethylene flows was believed to result from increased density of the formed polymer.

TABLE-US-00002 TABLE 2 Fabrication conditions and elastic properties of samples produced using HDMSO/C.sub.2H.sub.4 plasma. HDMSO C.sub.2H.sub.4 Flow Power Chamber Duration Apparent Elastic Sample Flow (sccm) (sccm) (W) Pressure (Pa) (seconds) Modulus (GPa) 5 10 10 750 20 180 0.6 6 10 20 750 20 180 1.1 7 10 30 750 20 220 1.3 8 10 40 750 20 240 2.7

[0097] Four more non-limiting layers (Samples 9-12) were formed using plasmas comprising HMDSO as well as argon (Ar) used to modify the HMDSO monomers of the plasma, under conditions described in Table 3. Increased argon flow generally reduced the elastic modulus, as shown in Table 3. The reduced modulus associated with higher argon flows was believed to have resulted from the formation of a higher proportion of CH.sub.3SiCH.sub.3 bonds in the formed polymer.

TABLE-US-00003 TABLE 3 Fabrication conditions and elastic properties of samples produced using HDMSO/Ar plasma. HDMSO Ar Flow Power Chamber Duration Apparent Elastic Sample Flow (sccm) (sccm) (W) Pressure (Pa) (seconds) Modulus (GPa) 9 10 10 750 20 180 5.7 10 10 20 750 20 180 3.6 11 10 30 750 20 220 1.7 12 10 40 750 20 240 0.9

[0098] These examples demonstrate the fabrication of layers with suitable elastic properties for use in textiles, and illustrate that elastic modulus of the layers can be controlled using plasma deposition methods.

Example 3

[0099] This example demonstrates the formation of non-limiting articles, some of which possessed desirable hydrophobic properties.

[0100] The non-limiting articles were produced using plasmas comprising different combinations of C.sub.2H.sub.4, Ar, and HMDSO to deposit and process material on a Nomex fabric substrate. All plasmas were provided with microwave (MW) power. Water contact angles were measured by using a sessile drop technique on a RameHart goniometer.

[0101] Table 4 presents the processing conditions of each plasma, and the water contact angle (WCA) measured for each sample. Table 4 also outlines the plasma processing steps taken to prepare each article, if multiple processing steps were required. Sample 13 was an article prepared by deposition of a single layer on a substrate using a mixed plasma. Sample 14 was an article prepared by deposition of two layers on a substrate, using a sequence of plasma deposition steps shown in Table 4. The first step comprised use of a plasma of pure C.sub.2H.sub.4, while the second step comprised use of a mixed plasma. Sample 15 was an article prepared by depositing a polymerized siloxane using a plasma comprising HMDSO and argon. Sample 16 was an article prepared by varying HDMSO, ethylene, and argon flow throughout four steps to create a gradient between polymerized HDMSO and polymerized ethylene.

TABLE-US-00004 TABLE 4 Fabrication conditions and water contact angles of non-limiting articles HDMSO C.sub.2H.sub.4 Ar Chamber Flow Flow Flow Power Pressure Duration WCA Sample Step (sccm) (sccm) (sccm) (W) (Pa) (seconds) (degrees) 13 1 10 8 500 10 150 83.1 14 1 16 500 25 600 85.5 2 10 8 500 20 150 15 1 10 64 900 10 100 142.7 16 1 10 16 500 10 100 158.3 2 10 8 16 900 10 100 3 10 32 900 10 100 4 10 64 900 10 100

[0102] The hydrophobicity rank before and after washing for 10 cycles (carried out according to ISO 6003:2012 (E) as described above) was measured. Table 5 presents the hydrophobicity rank of each sample before and after washing.

TABLE-US-00005 TABLE 5 Hydrophobic properties of articles. Pre-Wash Post-Wash Number Sample Hydrophobicity Rank Hydrophobicity Rank of Washes 13 4 3 10 14 4 3 10 19 7 4 10 15 8 5 10

[0103] Samples 15 and 16, had significantly higher water contact angles than Samples 13 and 14.

Example 4

[0104] This example demonstrates the formation of non-limiting articles, some of which possessed desirable hydrophobic properties.

[0105] The non-limiting articles were produced using plasmas comprising different combinations of C.sub.2H.sub.4, butadiene (C.sub.4H.sub.6), Ar, oxygen (O.sub.2), and HMDSO to deposit and process material on a Nomex fabric substrate. Unless otherwise noted, all plasmas were provided with microwave (MW) power. Table 6 presents the processing conditions of each plasma. Table 6 also outlines the plasma processing steps taken to prepare each article, if multiple processing steps were required. Sample 17 was prepared by a first step of depositing a homogeneous layer comprising a polymerized hydrocarbon, a second step of simultaneously sputtering nanoparticles onto the polymerized hydrocarbon and etching the polymerized hydrocarbon, and a third step of depositing a polymerized siloxane layer. Sample 18 was prepared by a first step of preparing a plurality of polymerized hydrocarbon nanostructures and a second step of depositing a polymerized siloxane layer. The plasma used in the first step of preparing Sample 18 was provided with radio-frequency (RF) power rather than microwave powerand the radio-frequency power corresponded to a microwave frequency power of approximately 900 W. Sample 19 was prepared by a first step of depositing a homogeneous layer comprising a polymerized hydrocarbon, a second step of simultaneously sputtering nanoparticles onto the polymerized hydrocarbon and etching the polymerized hydrocarbon, and a plurality of steps (3-6) to produce a concentration gradient between the polymerized hydrocarbon and a polymerized siloxane.

TABLE-US-00006 TABLE 6 Fabrication conditions of articles HDMSO C.sub.2H.sub.4 C.sub.4H.sub.6 Ar O.sub.2 Chamber Flow Flow Flow Flow Flow Power Pressure Duration Sample Step (sccm) (sccm) (sccm) (sccm) (sccm) (W) (Pa) (seconds) 17 1 16 500 8 100 2 20 700 8 5 3 10 64 900 8 100 18 1 10 RF = 30 80 180 2 10 64 900 10 100 19 1 16 500 8 600 2 20 700 8 5 3 10 16 900 8 100 4 10 8 16 900 8 100 5 10 32 900 8 100 6 10 64 900 8 100

[0106] The hydrophobicity and oleophobicity rank before and after washing carried out according to ISO 6003:2012(E) were measured as described above. Table 7 reports the water contact angle (WCA), the hydrophobicity rank, and the oleophobicity rank before and after washing. The hydrophobicity rank and the oleophobicity rank of untreated fabric was 0. Water contact angles were measured by using a sessile drop technique on a RameHart goniometer. All samples had high hydrophobicity and oleophobicity, as demonstrated by the water contact angles and oleophobicity ranks before and after washing. Furthermore, the samples retained high hydrophobicity and oleophobicity after washing.

TABLE-US-00007 TABLE 7 Hydrophobic and oleophobic properties of articles. Pre-Wash Post-Wash Pre-Wash Post-Wash WCA WCA Hydro- Hydro- Oleo- Oleo- Number before after phobicity phobicity phobicity phobicity of Sample wash wash Rank Rank Rank Rank washes 17 150.9 150.1 7 4 3 2 10 18 165.3 156.9 8 6 4 3 5 19 154.1 155.4 8 5 4 3 7

[0107] FIGS. 6A-6B are scanning electron microscope images of the fibers of Sample before and after exposure to the plasma, respectively. FIG. 6A shows the smooth surface of a fiber of Sample 18. By comparison the rough surface of the fiber shown in FIG. 6B results from the nanostructures deposited on the Nomex substrate of the sample, and positioned between the substrate and the polymerized HMDSO layer deposited on top of the nanostructures. This roughness gave rise to the oleophobicity and hydrophobicity of Sample 18.

[0108] These examples demonstrate the fabrication of layers with suitable oleophobic and/or hydrophobic properties for use in textiles, and illustrate that these properties may successfully endure a plurality of wash cycles.

[0109] While several embodiments of the present disclosure have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the functions and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the present disclosure. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present disclosure is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the disclosure described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the disclosure may be practiced otherwise than as specifically described and claimed. The present disclosure is directed to each individual feature, system, article, material, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, and/or methods, if such features, systems, articles, materials, and/or methods are not mutually inconsistent, is included within the scope of the present disclosure.

[0110] The indefinite articles a and an, as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean at least one.

[0111] The phrase and/or, as used herein in the specification and in the claims, should be understood to mean either or both of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Other elements may optionally be present other than the elements specifically identified by the and/or clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to A and/or B. when used in conjunction with open-ended language such as comprising can refer, in one embodiment, to A without B (optionally including elements other than B); in another embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0112] As used herein in the specification and in the claims, or should be understood to have the same meaning as and/or as defined above. For example, when separating items in a list, or or and/or shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as only one of or exactly one of, or, when used in the claims, consisting of, will refer to the inclusion of exactly one element of a number or list of elements. In general, the term or as used herein shall only be interpreted as indicating exclusive alternatives (i.e. one or the other but not both) when preceded by terms of exclusivity, such as either. one of. only one of, or exactly one of. Consisting essentially of, when used in the claims, shall have its ordinary meaning as used in the field of patent law.

[0113] As used herein in the specification and in the claims, the phrase at least one, in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase at least one refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, at least one of A and B (or, equivalently, at least one of A or B. or, equivalently at least one of A and/or B) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0114] As used herein, wt % is an abbreviation of weight percentage. As used herein, at % is an abbreviation of atomic percentage.

[0115] Some embodiments may be embodied as a method, of which various examples have been described. The acts performed as part of the methods may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include different (e.g., more or less) acts than those that are described, and/or that may involve performing some acts simultaneously, even though the acts are shown as being performed sequentially in the embodiments specifically described above.

[0116] Use of ordinal terms such as first. second. third, etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

[0117] In the claims, as well as in the specification above, all transitional phrases such as comprising, including, carrying, having, containing, involving, holding, and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases consisting of and consisting essentially of shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.