Atomic layer deposition of filter media

Abstract

Articles containing coated porous substrates and methods of making and using the same are provided. The article may be a filter media. The article includes a porous substrate having a non-reactive base polymer; a reactive polymer disposed on at least a portion of the base polymer, the reactive polymer having a surface energy higher than a surface energy of the non-reactive base polymer; and, a compound comprising a metal disposed on at least a portion of the reactive polymer. Vapor deposition may be used to place the compound on the reactive polymer.

Description

Cross-reference to related applications

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 456,344, filed March 31, 2023, which is incorporated herein by reference in its entirety. Technical Field

[0002] This disclosure provides filter media and methods for manufacturing such filter media. Specifically, this disclosure provides filter media for fluid (e.g., gas or liquid) filtration applications and methods for manufacturing such filter media. Summary of the Invention

[0003] This disclosure provides filter media and methods for manufacturing such filter media. Specifically, this disclosure provides filter media for fluid (e.g., gas or liquid) filtration applications and methods for manufacturing such filter media.

[0004] In one embodiment, a filter medium is provided, the filter medium comprising: a porous substrate comprising a non-reactive base polymer; a reactive polymer disposed on at least a portion of the base polymer; and a compound comprising a metal conformally disposed on at least a portion of the reactive polymer.

[0005] In another embodiment of this disclosure, a method for separating a substance (e.g., a contaminant) from a fluid is provided. The method includes exposing a filter medium, as described herein, to a fluid comprising the substance to capture the substance on the filter medium.

[0006] In another embodiment of this disclosure, a method for manufacturing a filter medium as described herein is provided. The method includes contacting at least a portion of a non-reactive base polymer with a mixture to form a coated base polymer, and placing a coating compound on at least a portion of the coated base polymer to form a filter medium.

[0007] The above overview of this disclosure is not intended to describe every disclosed embodiment or every implementation of this disclosure. The following description more precisely exemplifies illustrative embodiments. Throughout this application, guidance is provided by a list of examples / examples that may be used in different combinations. In each case, the listed examples serve only as a representative group and should not be construed as an exclusive list. definition

[0008] Unless otherwise stated, all scientific and technical terms used herein have their common meaning in the art. The definitions provided herein are intended to aid in understanding certain terms frequently used herein and are not intended to limit the scope of this disclosure.

[0009] Unless otherwise indicated, the terms "polymer" and "polymeric material" include, but are not limited to, organic homopolymers; copolymers, such as block, graft, random, and alternating copolymers, terpolymers, etc., and blends and modifiers thereof. Furthermore, unless otherwise specifically limited, the term "polymer" shall include all possible geometries of the material. These geometries include, but are not limited to, isotactic, syndiotactic, and atactic symmetries.

[0010] The term "alkyl" is used herein to denote a monovalent group, which is an alkane group / alkane radical and includes straight-chain, branched, cyclic, and bicyclic alkyl groups and combinations thereof (including both unsubstituted and substituted alkyl groups). Unless otherwise indicated, alkyl groups typically contain 1 to 30 carbon atoms. In some embodiments, alkyl groups contain 1 to 20 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, or 1 to 3 carbon atoms. Examples of "alkyl" include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, n-pentyl, isobutyl, tert-butyl, isopropyl, n-octyl, n-heptyl, ethylhexyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, and the like.

[0011] The term "alkylene" refers to a divalent group that is an alkane group and includes straight-chain, branched, cyclic, bicyclic, or combinations thereof. Unless otherwise indicated, alkylene typically has 1 to 30 carbon atoms. In some embodiments, alkylene has 1 to 20 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms. Examples of "alkylene" include methylene, ethylene, propylene, 1,4-butylene, 1,4-cyclohexylene, and 1,4-cyclohexyldimethylene.

[0012] The term "heteroatom" refers to a heteroatom (e.g., oxygen, sulfur, or nitrogen) that replaces at least one carbon atom in an alkyl, alkylene, or other carbon-containing group or molecule. For example, an ether group contains a heterooxygen atom with at least one carbon atom on each side of the oxygen atom.

[0013] Where the terms “comprises” and “includes”, and their variations, appear in the specification and claims, these terms are not restrictive. Such terms are to be understood as implying inclusion of the stated steps or elements / components, or groups of steps or elements / components, but not excluding any other steps or elements / components, or groups of steps or elements / components. “consisting of” means to include, and is limited to, anything following the phrase “consisting of.” Thus, the phrase “consisting of” indicates that the listed elements / components are necessary or mandatory, and that other elements / components may not be present. “Substantially constitutes” means to include any elements / components listed following the phrase, and is limited to other elements / components that do not interfere with or facilitate the activities or actions / behaviors specified for the listed elements / components in this disclosure. Thus, the phrase “substantially constitutes” indicates that the listed elements / components are necessary or mandatory, but other elements / components are optional and may or may not be present depending on whether they substantially affect the activities or actions / behaviors of the listed elements / components.

[0014] As used herein, the term “substantially” has the same meaning as “significantly” and can be understood to modify the following term by at least about 90%, at least about 95%, or at least about 98%. The term “substantially free of” a specific compound means that the compositions of the present invention contain less than 1,000 parts per million (ppm) of said compound.

[0015] As used herein, the term “substantially not” has the same meaning as “not significant” and can be understood to have the opposite meaning to “substantially”, i.e., modifying the following term with no more than 25%, no more than 10%, no more than 5%, or no more than 2%.

[0016] The term “about” is used herein in conjunction with numerical values ​​to include normal variation in measurements as would be expected by those skilled in the art, and should be understood to have the same meaning as “approximately” and to cover typical error tolerances, such as ±5% of the value.

[0017] Terms such as “a”, “an” and “the” are not intended to refer to a single entity, but rather to encompass the general categories that can be used to describe a particular instance.

[0018] The terms “a,” “one,” and “the” are used interchangeably with the term “at least one.” The phrases “at least one of…” and “including at least one of…” followed by a list refer to any item in the list and any combination of two or more items in the list.

[0019] As used herein, “have,” “having,” “include,” “including,” “comprise,” “comprising,” etc., are used in their open-ended sense and generally mean “including / comprises but not limited to.” It should be understood that “consistently composed of,” “comprises of,” etc., are included under the category of “including.” As used herein, “consistently composed of” refers to compositions, products / products, methods, etc., and therefore means that the components / ingredients of the composition, product / product, method, etc., are limited to the listed components / ingredients and any other components / ingredients that do not substantially affect the essential and novel characteristics of the composition, product / product, method, etc.

[0020] The terms "preferred" and "ideally" refer to embodiments that may provide certain benefits in certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are useless, and is not intended to exclude other embodiments from the scope of this disclosure, including the claims.

[0021] Any orientations mentioned herein, such as “top,” “bottom,” “left,” “right,” “up,” “down,” and other orientations and orientations, are described herein in conjunction with the accompanying drawings for clarity and are not intended to limit the actual apparatus or system or the use of the apparatus or system. Apparatus or systems as described herein can be used in multiple orientations and orientations.

[0022] The phrases “at least one of…” and “including at least one of…” followed by a list refer to any item in the list and any combination of two or more items in the list.

[0023] As used herein, the term "or" is generally used in its usual sense, including "and / or," unless otherwise expressly stated. The term "and / or" means one or all of the listed elements / components or a combination of any two or more of the listed elements / components.

[0024] Similarly, in this document, the numerical range described by the endpoints includes all numerical values ​​falling within the range as well as the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.). In this document, the “maximum” numerical value (e.g., at most 50) includes the numerical value (e.g., 50).

[0025] The terms “in the range” or “within a range” (and similar statements) include the endpoints of the range being stated.

[0026] Throughout this specification, references to "an embodiment," "an embodiment," "some embodiments," or "a number of embodiments" mean that a particular feature, configuration, composition, or characteristic described in connection with an embodiment is included in at least one embodiment of the invention. Therefore, the appearance of such phrases throughout this specification does not necessarily refer to the same embodiment of the invention. Furthermore, in one or more embodiments, particular features, configurations, compositions, or characteristics may be combined in any suitable manner. Attached Figure Description

[0027] Figure 1A This is a schematic cross-sectional view of a filter medium according to an embodiment of the present disclosure.

[0028] Figure 1B This is a schematic cross-sectional view of a filter medium having a coated substrate according to one embodiment.

[0029] Figure 2 This is a schematic cross-sectional view of a filter including the filter media of this disclosure.

[0030] Figure 3A and 3B These are SEM images of substrates without coating and with PVOH coating, 1 µm x 15,000.

[0031] Figure 4A This is a SEM image of the sample prepared in Example 2 without PVOH and subjected to 100 Al2O3 deposition cycles.

[0032] Figure 4B This is a SEM image of the sample prepared in Example 2 with PVOH and 100 Al2O3 deposition cycles.

[0033] Figure 4C This is a SEM image of the sample prepared in Example 2 without PVOH and subjected to 100 Al2O3 deposition cycles.

[0034] Figure 4D This is a SEM image of the sample prepared in Example 2 with PVOH and 100 Al2O3 deposition cycles.

[0035] Figure 4E This is a SEM image of the sample prepared in Example 2 without PVOH and subjected to 300 Al2O3 deposition cycles.

[0036] Figure 4F This is a SEM image of the sample prepared in Example 2 with PVOH and 300 Al2O3 deposition cycles.

[0037] Figure 4G This is a SEM image of the sample prepared in Example 2 without PVOH and subjected to 300 Al2O3 deposition cycles.

[0038] Figure 4H This is a SEM image of the sample prepared in Example 2 with PVOH and 300 Al2O3 deposition cycles.

[0039] Figure 5A and 5B This is a graph showing the average flow pore size (µm) as a function of the number of cycles for different atomic layer depositions (different atomic layer depositions) on ePTFE containing Al2O3 and TiO2 with and without PVOH.

[0040] Figure 6A The graph shows the water flux ratio (% compared to that after PVOH coating) of the samples prepared in Examples 2 and 3 as a function of the number of atomic layer deposition cycles (as a function of atomic layer deposition cycles).

[0041] Figure 6B This is a bar chart showing the water flux of the samples prepared in Comparative Examples 2 and 3 at different atomic layer deposition cycles.

[0042] Figure 7 This is a bar chart showing the weight percentage of different elements in the sample prepared in Example 2 using EDX analysis.

[0043] Figure 8A This is a SEM image of the sample prepared in Example 3 without PVOH and subjected to 150 TiO2 deposition cycles.

[0044] Figure 8B This is a SEM image of the sample prepared in Example 3 with PVOH and 150 TiO2 deposition cycles.

[0045] Figure 8C This is a SEM image of the sample prepared in Example 3 without PVOH and subjected to 150 TiO2 deposition cycles.

[0046] Figure 8D This is a SEM image of the sample prepared in Example 3 with PVOH and 150 TiO2 deposition cycles.

[0047] Figure 8EThis is a SEM image of the sample prepared in Example 3 without PVOH and subjected to 500 TiO2 deposition cycles.

[0048] Figure 8F This is a SEM image of the sample prepared in Example 3 with PVOH and subjected to 500 TiO2 deposition cycles.

[0049] Figure 8G This is a SEM image of the sample prepared in Example 3 without PVOH and subjected to 500 TiO2 deposition cycles.

[0050] Figure 8H This is a SEM image of the sample prepared in Example 3 with PVOH and subjected to 500 TiO2 accumulation cycles.

[0051] Figure 9A This is a graph showing the permeability measurements obtained at 1250 Pa and adjusted to 125 Pa on ePTFE with / without PVOH in Example 3 as a function of the number of TiO2 atomic layer deposition cycles (as a function of atomic layer deposition cycles).

[0052] Figure 9B This is a bar chart showing the permeability in different TiO2 atomic layer deposition cycles in Comparative Example 3.

[0053] Figure 10 This is a bar chart showing the weight percentage of different elements in the sample prepared in Example 3 using EDX analysis.

[0054] Figure 11 This is a bar chart showing the TGA analysis of the sample prepared in Example 3. Detailed Implementation

[0055] This disclosure relates to filter media and methods of manufacturing such filter media. Specifically, this disclosure relates to filter media and methods of manufacturing filter media for fluid (e.g., gas or liquid) filtration applications, as well as methods of manufacturing such filter media. According to embodiments of this disclosure, the material can be coated with a more reactive coating before depositing a metallic coating on a less reactive (e.g., non-reactive) substrate.

[0056] Atomic layer deposition (ALD) is a technique for growing thin films for a wide range of applications. ALD can be used to grow films (e.g., metal oxide films) on surfaces. ALD is a type of chemical vapor deposition (CVD) technique in which precursors are introduced in gaseous form into a reaction chamber to form the desired material via a chemical surface reaction. The mechanism of the ALD reaction involves the transfer of atoms between the precursor vapor and the surface. The transferred atoms can include, for example, hydrogen, oxygen, fluorine, and chlorine. The precursors react with the surface of the material one at a time in a sequential, self-limiting manner. At the temperature of a given ALD process, the precursors should react with the growth surface, not with themselves, which results in the self-limiting nature of ALD. Most ALD processes typically involve two or more precursors, each containing a different element that will deposit the material. Typically, two or more precursors are introduced separately onto the substrate surface, one at a time. It may be necessary for each precursor to saturate the surface, forming a monolayer of material. A first gas containing the first precursor can be introduced into the reaction chamber containing the surface to be treated. Once the surface is covered by a monolayer of the first gas, saturation is achieved. Excess gas is pumped out of the reaction chamber, and a second gas containing the second precursor is introduced. The second gas is condensed and chemisorbed / chemically adsorbed onto the top of the first layer. Excess second gas is pumped out. The entire process can be repeated to deposit a second monolayer. This sequence can be repeated as needed until the desired film is slowly deposited by repeated exposure to the individual precursor. To be suitable for this process, the ALD precursor needs to have specific properties, such as sufficient volatility, thermal stability, and self-limiting reactivity with the surface. Suitable precursor pairs can deposit oxides of some pure elements, oxides of most elements, nitrides of many elements, sulfides, selenides, and tellurides of some elements, and phosphides, arsenides, carbides, fluorides, and combinations thereof of a few elements.

[0057] ALD (Advanced Layer Deposition) can maintain the basic structure of an underlying surface (e.g., a substrate) by simultaneously altering the physical and / or chemical properties of the surface through the addition of a conformally self-limiting coating. These alterations can affect the physical and chemical properties of the medium and provide additional applications for which the medium may be suitable. The substrate often bonds to the precursor with a certain affinity, allowing adhesion to the substrate. In ALD, the substrate acts as the first layer of the bonded surface, preventing loss when exposed to a second or third set of precursors. A wide variety of substrates can be used, depending on the reaction and the resulting coating of interest.

[0058] In some cases, it may be necessary to coat materials with low surface energy. Surface energy is a term used to describe the properties of a given substrate surface. High surface energy implies strong molecular attraction, while low surface energy implies weak molecular attraction. When using ALD to coat materials with low surface energy, the low surface energy of the substrate may lead to slow or insufficient bonding of the first precursor, and thus may cause the ALD process to start very slowly and proceed in a non-conformal / conformal manner.

[0059] PTFE is used in various fields, from everyday life to a wide range of industrial applications. PTFE is used as a substrate for filter media due to its good thermal stability, excellent chemical resistance, high mechanical strength, and low dielectric constant. Porous PTFE membranes, known as "ePTFE," are manufactured using a stretching process. ePTFE stands for expanded polytetrafluoroethylene, available as a porous membrane. ePTFE can form one or more layers of filter media and can be used in filters for air and solvent purification. However, the strong hydrophobicity of ePTFE can degrade its performance when used in contact with water. PTFE has a low surface energy due to the high density of fluorine on its surface. This can make the initial steps of the ALD process challenging when depositing precursors on the PTFE surface. To create coatings on low surface energy materials such as PTFE using ALD, an increased number of deposition cycles is required, which increases the cost and time required to manufacture such coatings. Additionally, it can be difficult to produce conformal coatings on low surface energy materials using ALD. As used herein, the term "conformal" refers to a coating that follows the surface profile of the substrate, such that the coating is present across the entire surface, regardless of surface roughness or defects. The term "non-conformal" refers to a coating that does not follow the surface profile of the substrate and is not present across the entire surface, regardless of surface roughness or defects. When comparing conformal and non-conformal coatings, it may sometimes be observed that conformal coatings are smoother and more uniformly distributed across the entire surface, while non-conformal coatings have more nodules and are less uniformly distributed.

[0060] For example, metal oxides such as Al₂O₃ and TiO₂ are highly hydrophilic due to their high surface energy. As used herein, the term "hydrophilic" has the same meaning as "particularly hydrophilic" and can be understood as having a tendency to mix with water, dissolve in water, or be wetted by water, and can be understood as having the opposite meaning to "hydrophobic." Similarly, the term "oleophobic" as used herein has the meaning of "lacking affinity for oil" and can be understood as having the opposite meaning to "oleophilic." Hydrophobic materials are defined as materials with a water contact angle greater than 90°, while hydrophilic materials are defined as materials with a water contact angle less than 90°. Hydrophilicity can be measured by using the ASTM D7334-08R22 test method to measure the water contact angle of a material or by using an automated contact angle tester and the ASTM D5725-99 test method.

[0061] Al₂O₃ or TiO₂ deposition on PTFE via ALD has been found to increase the hydrophilicity of the PTFE surface. However, improving the adhesion between the deposited layer and the PTFE substrate is desirable. When depositing metal oxides on substrates with low surface energy, the resulting deposits may exhibit high nodularity and uneven distribution of the deposited metal oxides. An improved method for applying metal oxides to low surface energy materials via ALD is desired. It is desirable to apply the metal oxides to the substrate in a more uniform layer. Therefore, when adding a metal oxide coating, it is necessary to modify the physical and chemical properties of the low surface energy material by controlling the surface energy of the substrate.

[0062] According to embodiments of this disclosure, the surface properties of low surface energy materials can be modified by adding an intermediate coating of higher surface energy materials to prepare a surface for chemical vapor deposition of metal oxides. Filter media

[0063] See now Figure 1A-2 This disclosure describes a coated filter medium 10, a filter 200 including the filter medium 10, a method of manufacturing the filter medium 10, and a method of using the filter medium 10. It should be noted that although the figures show a coated filter medium, the methods of this disclosure can also be used to apply coatings to the surfaces of other articles. In particular, the methods of this disclosure can be used to apply coatings to articles including porous surfaces with low surface energy, which can benefit from the improved ability to form conformal coatings.

[0064] like Figure 1A The diagram schematically illustrates that the filter medium 10 of this disclosure generally comprises a porous substrate 20 coated with a metal-containing compound 51. According to one embodiment, the metal-containing compound 51 is applied as a coating 50 to the medium using an ALD or other similar deposition method.

[0065] The porous substrate 20 may include a non-reactive base polymer 31. The non-reactive base polymer 31 can form the porous substrate 20, such as... Figure 1A As shown. The porous substrate 20 made of the non-reactive base polymer 31 may be referred to as the base layer 21. According to one embodiment, a reactive layer 40 of the reactive polymer 41 may be disposed on at least a portion of the base layer 21. In some cases, the reactive layer 40 may completely coat the base layer 21, forming a conformal coating on the base layer 21. The reactive layer 40 of the reactive polymer 41 may be disposed on the non-reactive base polymer 31 forming the porous substrate 20. A metal-containing compound 51 may form a coating 50 disposed on at least a portion of the reactive layer 40. The non-reactive base polymer 31 may be a material with low surface energy. A base polymer with a low surface energy, for example, not greater than 37 mN / m, may be considered "non-reactive". The base polymer may have a surface energy as low as, for example, about 20 mN / m. In some cases, it may be necessary to coat a base polymer with a higher surface energy, for example, up to 40 mN / m. The reactive polymer 41 may be a material with a higher surface energy than the non-reactive base polymer 31. In other words, the reactive polymer 41 can be selected based on the surface energy of the non-reactive base polymer 31, such that the surface energy of the reactive polymer 41 is greater than that of the non-reactive base polymer 31. In some embodiments, the term "reactive polymer" refers to a material with a surface energy of 37 mN / m or higher.

[0066] In some embodiments, the filter medium 110 includes a porous substrate 120 coated with a layer 130 of a non-reactive base polymer 131, such as Figure 1B As shown in the diagram, a layer 130 of porous substrate 120 and non-reactive base polymer 131 together form a base layer 121. The porous substrate 120 can be made of any suitable material, including materials with low, medium, or high surface energy. The surface properties of the base layer 121 can be determined based on the properties of the non-reactive base polymer 131 that forms the layer 130 of the coated porous substrate 120. The base layer 121 can have a surface energy similar to... Figure 1A The substrate 21 shown has similar properties (e.g., low surface energy). To apply a coating 50 containing the metal compound 51 to the substrate 121, the substrate 121 can be modified by adding a reactive layer 40 of the reactive polymer 41 to the substrate 121. The reactive polymer 41 can coat at least a portion of the substrate 121. In some cases, the reactive layer 40 can completely coat the substrate 121, forming a conformal coating on the substrate 121. The coating 50 containing the metal compound 51 can be placed on at least a portion of the reactive layer 40.

[0067] Generally, the porous substrates 20 and 120 are not solid layers. The porous substrates 20 and 120 may have a fibrous structure (e.g., a nonwoven medium), a porous membrane structure, or a sponge-like structure. Although the individual layers or coatings 40, 50, and 130 are shown as solid layers, said layers or coatings 40, 50, and 130 may at least partially coat each fiber or porous surface of the porous substrates 20 and 120. That is, layers or coatings 40, 50, and 130 may form conformal coatings on the porous substrates 20 and 120.

[0068] In some embodiments, the substrates 21, 121 have a first main surface 1 and an opposing second main surface 2, and thicknesses T21, T121 between the first main surface 1 and the second main surface 2. The thicknesses T21, T121 can be measured in a direction perpendicular to the first main surface 1 and the second main surface 2. At least a portion of the metal-containing compound 51 is distributed throughout the thicknesses T21, T121. That is, the metal-containing compound 51 can exist not only as different layers on the surfaces of the substrates 21, 121, but also within the substrates 21, 121, for example, on fibers and / or within pores. The compound 51 can form a conformal layer on the porous substrates 20, 120, at least partially coating the fibers and / or pores of the porous substrates 20, 120. The amount of the metal-containing compound 51 within the filter media 10, 110 can be determined, for example, by elemental analysis, such as thermogravimetric analysis using ASTM E1131-20. Cross-sectional elemental analysis has identified a metal-containing compound 51 (including on the second primary surface 2 of the medium) extending through thicknesses T21 and T121 of the base layers 21 and 121. In some embodiments, based on elemental analysis (e.g., ASTM E1131-20), 20 wt% or more of the metal-containing compound 51 is contained within the thicknesses T21 and T121 of the base layers 21 and 121.

[0069] In some embodiments, the coating is patterned on the filter media 10, 110. Patterning can be achieved by any suitable method, such as blocking portions of the substrates 21, 121 before applying the reactive polymer 41, blocking portions of the reactive polymer 41 before applying the metal-containing compound 51 via ALD, or applying the reactive layer 40 or the coating 50 containing the metal compound 51 in a patterned manner. Any suitable regular or irregular pattern can be used as needed. The filter media 10, 110 may have multiple areas including the reactive layer 41 and the coating 50 containing the metal compound 51. In some embodiments, one area of ​​the substrates 21, 121 is coated while another area is uncoated. Therefore, the filter media 10, 110 may include: coated areas or areas containing the coating 50 and uncoated areas or areas not containing the coating 50.

[0070] Filter media 10 and 110 can have permeabilities within a wide range. The permeability of filter media 10 and 110 may be affected by the porous substrates 20 and 120, the layer 130 of the non-reactive polymer 131, the reactive layer 40, and the coating 50. For example, the permeability of filter media 10 and 110 may be affected by the inherent permeability of the porous substrates 20 and 120. The permeability of filter media 10 and 110 may also be affected by the thickness of the individual layers and coatings 130, 40, and 50. The permeability of filter media 10 and 110 may also be affected by the chemical composition of the individual layers and coatings 130, 40, and 50 (particularly coating 50, which contains the metal compound 51). The permeability of the media can be measured by measuring its Frazier permeability using a Frazier Permeability Tester available from Frazier Precision Instrument Co. Inc., Gaithersburg, Maryland, as described in ASTM D737-18. Fraser permeability is measured in units of 1 cfm / ft at a water pressure drop of 0.5". 2 It is equal to 0.5 cm at 125 Pa. 3 / s / cm 2 In some embodiments, the filter media 10, 110 have a density of 0.02 cm. 3 / s / cm 2 Or larger, 0.05cm 3 / s / cm 2 Or larger, 0.1cm 3 / s / cm 2 Or larger, 0.2cm 3 / s / cm 2 Or larger, 0.3cm 3 / s / cm 2 Or larger, or 0.5cm 3 / s / cm 2 Or even higher permeability. The permeability of filter media 10 and 110 can be 2 cm. 3 / s / cm 2 Or smaller, 1.5 cm 3 / s / cm 2 Or smaller, 1.0 cm 3 / s / cm 2 Or smaller, or 0.8 cm 3 / s / cm 2 Or smaller. Porous substrates

[0071] Any suitable porous substrate can be coated using the methods of this disclosure. Furthermore, any suitable porous substrate can be used in the filter media of this disclosure. The coating methods of this disclosure are particularly suitable for porous substrates that are non-reactive and exhibit low surface energy (e.g., below 37 mN / m), or coated with non-reactive materials exhibiting low surface energy. When such substrates are prepared to have a porous structure, they can be used as filter media 10. Exemplary porous substrates include fibrous porous webs (e.g., nonwoven media), porous membranes, or other porous structures such as ePTFE. Porous substrates can be made from a variety of materials (e.g., various polymers).

[0072] In some embodiments, the porous substrate or the coating on the porous substrate has a surface that exhibits low surface energy due to the inclusion of a non-reactive material (e.g., a non-reactive polymer).

[0073] The porous substrate or coating on the porous substrate may have a relatively low surface energy, such as 37 mN / m or less, 35 mN / m or less, 32 mN / m or less, 30 mN / m or less, 25 mN / m or less, or 20 mN / m or less. The porous substrate or coating on the porous substrate may exhibit the surface energy of a non-reactive material (e.g., a polymer). In some embodiments, the non-reactive polymer has a surface energy of no more than 37 mN / m. In some embodiments, the non-reactive polymer has a surface energy of 37 mN / m or less. In some embodiments, the non-reactive polymer has a surface energy of about 32 mN / m. In some embodiments, the non-reactive polymer has a surface energy of about 20 mN / m.

[0074] Non-reactive base materials / substrates may include polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), sulfonated tetrafluoroethylene, polyvinyl fluoride, oleophobic polyethersulfone (e.g., PES coated with an oleophobic coating), polypropylene, nonwoven polypropylene, polyethylene, ethylene-vinyl acetate, polydimethylsiloxane, chloroprene rubber, polyisobutylene, polymethyl vinyl ether, polybutadiene, polypropylene glycol, any combination of two or more of these (including mixtures and copolymers), nonwoven materials made therefrom, and films made therefrom. In some embodiments, the non-reactive material (e.g., the polymer) includes an oleophobic polymer. In some embodiments, the non-reactive material includes an oleophobic processed material. In some embodiments, the non-reactive material includes both an oleophobic polymer and an oleophobic processed material. Suitable oleophobic polymers have very little or no affinity for oil or completely repel oil, thereby preventing or limiting the passage of oil through filter media 10. The oleophobicity of the material can be measured by AATCC test method 118-1997 Oil repellency: Hydrocarbon resistance test. Typically, when tested with oil, oleophobic polymers exhibit a contact angle greater than 90 degrees. Examples of oleophobic polymers include polymers made from perfluorooctanoic acid (PFOA), other perfluorinated carboxylic acids (e.g., C6, C4, C3, C2, and C1), and polydimethylsiloxane (PDMS). Examples of oleophobic processed products include coatings with oleophobic polymers.

[0075] Porous substrates coated with low surface energy materials can include base substrates (e.g., polymers) that do not exhibit low surface energy. For example, porous substrates can include coated cellulose acetate fiber webs or membranes. Other examples of coated porous substrates include substrates made from polyesters, polyethersulfones, polyvinyl chloride, nylon, polyacrylic acid, polystyrene, polyurethanes, cellulose, polyimide, acrylonitrile butadiene styrene, or combinations thereof.

[0076] It may be necessary to modify the filter medium 10 by applying a metal oxide to the substrate 20 of the filter medium 10 to enhance the hydrophilicity of the substrate 20.

[0077] In some embodiments, the porous substrate comprises an expandable non-reactive base polymer. Examples of expandable non-reactive base polymers include ePTFE (expanded polytetrafluoroethylene), ePP (expanded polypropylene), and ePE (expanded polyethylene).

[0078] In some embodiments, the porous substrate is or includes a porous membrane. In some embodiments, the porous substrate is or includes ePTFE. In some embodiments, the porous substrate is or includes a porous fiber mesh.

[0079] Porous substrates can have any suitable pore size as needed. The pore size can be selected to suit a given application and can be adjusted by regulating the thickness of the layers, including non-reactive material layers, reactive layers, and ALD coatings. In some cases, the substrate can be highly porous with relatively large pores, such as materials suitable for use as loosely woven fabrics. In other cases, the substrate can have extremely small pores, such as materials suitable for microfiltration or nanofiltration. In some embodiments, the porous substrate has an average pore size of 1 mm or less, 100 µm or less, 10 µm or less, 1 µm or less, 0.1 µm or less, or 0.01 µm or less. The porous substrate can have an average pore size of 1 nm or greater, 5 nm or greater, 10 nm or greater, 0.1 µm or greater, 1 µm or greater, 10 µm or greater, or 100 µm or greater. The average pore size of porous substrates can range from 1 nm to 1 mm, 1 nm to 1 µm, 1 nm to 0.5 µm, 1 µm to 1 mm, or 100 µm to 1 mm. The method for measuring pore size is described in ASTM D6767-21. Reaction layer

[0080] The substrate comprises a non-reactive base material, such as a non-reactive polymer. According to one embodiment, at least a portion of the substrate (comprising a porous substrate and an optional coating of non-reactive material) is coated with a layer of reactive polymer.

[0081] In some embodiments, the reactive polymer has a higher surface energy than the non-reactive polymer. Higher surface energy enables more uniform deposition and stronger adhesion of metal-containing compounds on the substrate. The reactive polymer can be selected based on its surface energy compared to the base polymer. For example, the reactive polymer can be selected to have a surface energy at least 2 mN / m higher than the base polymer. The surface energy of the reactive polymer can be at least 5 mN / m, at least 10 mN / m, or at least 15 mN / m higher than the base polymer. In some embodiments, the non-reactive base polymer has a surface energy of about 18-22 mN / m, and the reactive polymer has a surface energy of 30 mN / m or greater, 35 mN / m or greater, 37 mN / m or greater, 40 mN / m or greater, or 45 mN / m or greater. The surface energy of the reactive polymer can be up to 80 mN / m. In some embodiments, the non-reactive base polymer has a surface energy of about 35-38 mN / m, while the reactive polymer has a surface energy of 37 mN / m or greater, 40 mN / m or greater, or 45 mN / m or greater.

[0082] In some embodiments, the reactive polymers include polyvinyl alcohol (PVOH), polymethyl methacrylate (PMMA), polyacrylic acid (PAA), polyhydroxyethyl methacrylate (pHEMA), poly(caprolactam), polyethylene terephthalate (PET), polyethylene glycol (PEG), polysulfone (PS), polyacrylonitrile (PAN), polyacrylamide (PAM), and combinations of two or more thereof (including mixtures and copolymers).

[0083] Methods for coating non-reactive base polymers with reactive polymer materials are conventional and well known to those skilled in the art. For example, a porous substrate can be coated by immersion, dip coating, spraying, printing, or brushing a solution containing the reactive polymer onto the porous substrate. The porous substrate can be pre-wetted before coating. The coated substrate can be rinsed after coating. The coating can be dried and / or cured onto the porous substrate. In one exemplary embodiment, the porous substrate is pre-wetted using a water-miscible solvent (e.g., acetone, ethanol, or isopropanol). The solvent can be replaced with water. The substrate (still wetted with water) can be placed in contact with a room-temperature water bath containing poly(vinyl alcohol). For example, the substrate can be placed in a water bath containing 1-2 wt% fully (99%) hydrolyzed poly(vinyl alcohol) for at least 2 minutes. Room temperature is understood to mean a temperature of about 20°C to 26°C. The substrate can then be rinsed. In some embodiments, the substrate can be rinsed with water and immersed in an aqueous solution of glutaraldehyde and H₂SO₄ at elevated temperatures. For example, the substrate can be immersed in an aqueous solution of 2 mM to 8 mM (e.g., about 60°C) glutaraldehyde and 0.1 M to 0.5 M (e.g., about 0.25 M) H2SO4 for 1 to 5 minutes (e.g., about 2 minutes) at a temperature of 40°C to 80°C (e.g., about 60°C).

[0084] According to an embodiment, the surface is coated with a compound containing a metal. The surface may be a porous surface. The surface may be the surface of a filter medium. The coating can be applied to the surface coated with the reactive polymer by ALD or another deposition method.

[0085] In some embodiments, the coating compound may be a metal-containing compound. In some embodiments, the metal-containing compound is a pure metal, a metal oxide, a metal alkoxide, an amino metal, a metal sulfide, a metal fluoride, or any combination of two or more thereof. In some embodiments, the metal-containing compound is M... n X m M n O m M n N m M n S m M n C m Or Mn R m In this system, M is a metal, X is a halogen (e.g., fluorine, chlorine, or iodine), R is a carbonaceous group optionally substituted with one or more heteroatoms (e.g., oxygen, nitrogen, sulfur, or similar atoms), n is an integer from 1 to 4 (e.g., 1 to 3, 1 to 2, or 1), and m is an integer from 1 to 6 (e.g., 1 to 5, 1 to 4, 1 to 3, 1 to 2, or 1). R can be alkyl, alkylene, or substituted alkyl or alkylene groups, such as alkoxide groups, alkylamine groups, alkylamide groups, or similar groups. R can be straight-chain, branched, or cyclic, and can contain straight-chain, branched, and / or cyclic segments. R can be saturated or unsaturated. Exemplary metals include aluminum, calcium, copper, erbium, gallium, hafnium, iridium, lanthanum, magnesium, palladium, platinum, niobium, ruthenium, scandium, silicon (metalloid), strontium, tantalum, titanium, vanadium, yttrium, ytterbium, zinc, zirconium, etc. Exemplary metal-containing compounds include Al₂O₃, CaO, CuO, Er₂O₃, Ga₂O₃, HfO₂, La₂O₃, MgO, Nb₂O₅, Sc₂O₃, SiO₂, Ta₂O₅, TiO₂, and VR. n (e.g., vanadium acetylacetonate or cyclopentadienylvanadium), V(OHR) n (e.g., vanadium butoxide, vanadium ethanol, vanadium methanol, vanadium propoxide, or vanadium tetraethanol), TiOHR n , Y2O3, Yb2O3, ZnO, ZrO2, AlN, GaN, TaR n (e.g., pentapenta(dimethylamino)tantalum), TiAlN, TiR n (e.g., tetra(dimethylamino)titanium, tetra(ethylmethylamino)titanium), TaC, TiC, Ir, Pd, Pt, Ru, ZnS, SrS, CaF2, LaF3, MgF2 and SrF2, and combinations of any two or more thereof, wherein R, n and m are as described above.

[0086] According to one embodiment, the filter media or other substrate includes one or more metal-containing compounds deposited on the substrate by chemical vapor deposition. In some embodiments, the chemical vapor deposition is ALD. When using ALD, the metal-containing compound may be applied in two or more precursor forms. The metal-containing precursor may then be oxidized with an oxygen-containing precursor. Precursors of the metal-containing compound include, for example, tetrakis(dimethylamino)titanium (iv), tetrakis(ethylmethylamino)titanium, cyclopentadienyl(cycloheptadienyl)titanium (ii), pentamethylcyclopentadienyltrimethylethanoltitanium, pentamethylcyclopentadienyltri(dimethylamino)titanium (iv), tetrakis(diethylamino)titanium (iv), n-butoxidetitanium (iv), tert-butoxidetitanium (iv), titanium chloride (iv), (di-isopropanol)bis(acetylpyruvate)titanium, (di-isopropanol)bis[brew]titanium (iv), titanium ethoxide (iv), isopropoxidetitanium (iv), tris(2,2,6,6-tetramethyl-3,5-heptadecyl) Titanium (iii), hexa(dimethylamino)aluminum, aluminum acetylacetonate, aluminum sec-butoxide, aluminum chloride, aluminum ethoxide, aluminum hexafluoroacetylpyruvate, aluminum iodide, aluminum isopropoxide, aluminum isopropoxide, dimethyl aluminum isopropoxide, triisobutylaluminum, triethylaluminum, triethyl(trisec-butoxy)aluminum, diethyl(tetrasec-butoxy)aluminum, tetraethyl(disec-butoxy)aluminum, trimethylaluminum, tri(2,2,6,6-tetramethyl-3,5-heptanedione)aluminum, triethylaluminum, titanium chloride (IV), bis(cyclopentadienyl)dimethylhafnium, hafnium ethoxide (IV), hexamethyldisiloxane, and combinations of two or more of these.

[0087] The thickness of the coating (e.g., a metal oxide coating) can be adjusted as needed. In some cases, a thicker coating may be required, while in others, an extremely thin coating may be necessary. In some embodiments, the filter media comprises 1 wt% or more, 2 wt% or more, 5 wt% or more, 10 wt% or more, 15 wt% or more, or 20 wt% or more of a metal compound, expressed as a percentage of total filter media weight, by thermogravimetric analysis (TGA). In some embodiments, the filter media comprises 50 wt% or less, 40 wt% or less, 30 wt% or less, 20 wt% or less, 15 wt% or less, 10 wt% or less, or 5 wt% or less of a metal compound, expressed as a percentage of total filter media weight. The filter media may comprise 2 wt% to 50 wt% of a metal compound, expressed as a percentage of total filter media weight. ASTM-E1131-20 can be used to measure the wt% of the metal compound in the media by TGA.

[0088] Filter media with suitable pore sizes can be prepared as needed. The desired pore size can be selected to suit a given application and can be adjusted by regulating the thickness of the layers (including non-reactive material layers, reactive layers, and ALD coatings). In some cases, the filter media can be highly porous and have relatively large pores, such as materials suitable for use as loose cloth. In other cases, the filter media can have extremely small pores, such as materials suitable for microfiltration or nanofiltration. In some embodiments, the filter media has an average pore size of 1 mm or less, 100 µm or less, 10 µm or less, 1 µm or less, 0.1 µm or less, or 0.01 µm or less. The filter media can have an average pore size of 1 nm or greater, 5 nm or greater, 10 nm or greater, 0.1 µm or greater, 1 µm or greater, 10 µm or greater, or 100 µm or greater. The average pore size of the filter media can range from 1 nm to 1 mm, 1 nm to 1 µm, 1 nm to 0.5 µm, 1 µm to 1 mm, or 100 µm to 1 mm. The method for measuring pore size is described in ASTM D6767-21.

[0089] In addition to other parameters, water flux can be used to further evaluate the properties of the filter media. Water flux can be measured according to the water flux test described herein. In some embodiments, the media has a flux of 2000 L / m³. 2 / min / psi or less, up to 40 L / m 2 / min / psi, up to 1 L / m 2 / min / psi, or at most 0.1 L / m 2 / min / psi water flux. Manufacturing method

[0090] The coated substrate (e.g., a coated filter medium) disclosed herein can be prepared by first applying a reactive layer containing a reactive polymer to a substrate, and then applying a metal-containing compound to the reactive layer. The metal-containing compound can be applied by a deposition method, such as chemical vapor deposition, for example, ALD.

[0091] As explained above, the porous substrate 20 or the coating 130 on the porous substrate comprises non-reactive base polymers 31, 131. The non-reactive base polymer, or at least a portion thereof, may optionally be initially contacted with a wetting liquid. In some embodiments, the non-reactive base polymer 30 is wettable. As used herein, the term "wetting" refers to a material that allows fluid to diffuse uniformly across its surface. In the case of a porous wettable surface, the fluid will penetrate into the material and diffuse uniformly until the full volume / amount of fluid has diffused as much as possible. The wettability of the material can be measured using the ASTM D7334-08R22 test method. The wetting liquid is or may contain one or more water-miscible solvents, such as acetone, ethanol, ethylamine, ethylene glycol, acetonitrile, methanol, 1-propanol, pyridine, or isopropanol. In some embodiments, the non-reactive base polymers 31, 131 are polytetrafluoroethylene and the wetting liquid is isopropanol.

[0092] The non-reactive base polymer, or at least a portion thereof, is then contacted with the mixture to form a coated base polymer. The mixture may contain a reactive polymer and a carrier. The mixture may be a solution of the reactive polymer in the carrier. The reactive polymer may contain one or more of the following: polyvinyl alcohol (PVOH), polymethyl methacrylate (PMMA), polyacrylic acid (PAA), polyhydroxyethyl methacrylate (pHEMA), poly(caprolactam), polyethylene terephthalate (PET), polyethylene glycol (PEG), polysulfone (PS), polyacrylonitrile (PAN), polyacrylamide (PAM), and mixtures and copolymers thereof. The reactive polymer may be contained in the mixture at a concentration of 0.25 wt% to 5 wt%. The carrier may contain one or more solvents. The carrier may be selected such that the reactive polymer is soluble in the carrier. Alternatively, the reactive polymer may be partially dissolved or emulsified in the carrier. In such cases, the carrier may contain one or more adjuvants, such as surfactants, dispersants, or the like. The carrier may also contain a crosslinking agent. A suitable crosslinking agent may be selected based on the reactive polymer. Examples of suitable crosslinking agents include glutaraldehyde, boric acid, and formaldehyde. Contacting the non-reactive base polymer with the mixture can include immersing or dip-coating the base polymer into the mixture, or spraying, printing, or brushing the mixture onto the non-reactive base polymer. The mixture can at least partially penetrate the porous substrate, such that the inner surfaces (e.g., the surfaces of individual fibers or pores) are coated. The mixture can optionally be applied in a pattern to obtain a patterned coating.

[0093] The method may further include crosslinking a reactive polymer, a non-reactive base polymer, or both. In some embodiments, only the reactive polymer is crosslinked. In some embodiments, both the reactive polymer and the non-reactive base polymer are crosslinked. The reactive polymer may be covalently bonded to the non-reactive base polymer.

[0094] The method may include other steps, such as rinsing, deactivation, drying, curing, or any combination of two or more thereof. The coated substrate may be dried and / or crosslinked by exposing it to an elevated temperature for a period of time.

[0095] The method further includes placing a metal-containing compound onto at least a portion of a coated base polymer to form a filter medium. In some embodiments, chemical vapor deposition (CVD) is used to place the compound. CVD can be atomic layer deposition (ALD). ALD is well known to those skilled in the art and is used to grow metal oxide films on surfaces. The process begins when an initiator is adsorbed onto the material surface and then onto a reactive chemical substance containing the metal. The initiator can be an oxygen-containing compound, such as water. The reaction of the initiator with the metal results in the formation of a metal oxide monolayer on the surface. This process can be repeated in a cyclic manner until the desired thickness is achieved. The ALD reaction can use two or more precursors. Thin films can be deposited slowly by repeatedly exposing the individual precursors. Exemplary precursors include one or more of the following: aluminum, antimony, arsenic, barium, beryllium, bismuth, boron, cadmium, calcium, carbon, cerium, chromium, cobalt, copper, dysprosium, erbium, europium, gadolinium, gallium, germanium, gold, hafnium, holmium, indium, iridium, iron, lanthanum, lead, lithium, lutetium, magnesium, manganese, molybdenum, neodymium, nickel, niobium, nitrogen, osmium, palladium, phosphorus, platinum, potassium, praseodymium, rhenium, rhodium, ruthenium, samarium, scandium, selenium, silicon, silver, sodium, strontium, tantalum, terbium, thallium, thulium, tin, titanium, tungsten, vanadium, xenon, ytterbium, yttrium, zinc, and zirconium. Precursors can be organometallic or metal salts, or organosilicon compounds. For example, a precursor can be an organometallic compound containing aluminum, titanium, or hafnium, or a salt of aluminum or titanium. In some embodiments, the ALD precursor comprises aluminum chloride, triethylaluminum, tetra(ethylmethylamino)titanium, titanium chloride (IV), bis(cyclopentadienyl)dimethylhafnium, hafnium ethanol (IV), hexamethyldisiloxane, or a combination of one or more of these. Filter

[0096] The filter media disclosed herein can be used in a filter. A filter may include a filter media and a housing. A schematic depiction of filter 200 is shown in... Figure 2The filter 200 has a housing 220 defining an interior 221, an inlet 201, and an outlet 202. Filter media 210 is disposed within the interior 221 in the fluid flow path between the inlet 201 and the outlet 202. Although shown in a cylindrical shape, the filter housing 220 can have any suitable shape and size to suit the intended application. The filter media 210 can be disposed within the filter housing in any desired configuration, including cylindrical, enclosed, pleated, planar, layered, etc. The filter media 210 can be arranged in a through-flow configuration or a cross-flow configuration. How to use

[0097] The filter media of this disclosure can be used to separate compounds or contaminants of interest from fluids. The fluid can be a gas or a liquid. The fluid can contain or be an aqueous liquid. The fluid can contain or be an organic solvent. For example, the fluid can contain aqueous solutions, aqueous beverages, organic solvents or solutions containing organic solvents, gases, or mixtures of gases. In some embodiments, the fluid is a beverage, such as water, beer, wine, or milk. In some embodiments, the fluid is an acidic or alkaline solution. In some embodiments, the fluid includes an oxidizing agent, such as hydrogen peroxide. In some embodiments, the fluid is or contains acetonitrile, hexane, amine solutions, toluene, tetrahydrofuran (THF), ethanol, methanol, dichloromethane, or the like. In some embodiments, the fluid is a gas or a mixture of gases, such as air, helium, nitrogen, carbon dioxide, or the like. The filter media of this disclosure can be used to separate particulate contaminants from liquids or gases, including silica dust, metal particles, bacteria, viruses, ions, organic materials, etc.

[0098] According to one embodiment, the method of using a filter medium disclosed herein relates to separating substances, such as contaminants, from a fluid. The method includes exposing the filter medium to a fluid containing the substance for a period of time to capture the substance. The substance may be adsorbed or absorbed onto the filter medium. The substance may be removably coupled to the surface of the filter medium. The filter medium can be used in a variety of separation modes, including size exclusion, interception, inertial impaction, electrostatic attraction, adsorption, absorption, coalescence, or combinations of two or more of these. Exemplary embodiments

[0099] Example 1 is a filter medium, comprising: A porous substrate comprising a non-reactive base polymer; A reactive polymer, wherein the reactive polymer is disposed on at least a portion of a base polymer, the surface energy of the reactive polymer being higher than the surface energy of the non-reactive base polymer; and A compound including a metal, said compound being placed on at least a portion of a reactive polymer.

[0100] Example 2 is a filter medium according to Example 1, wherein the porous substrate includes a fibrous porous mesh (e.g., a nonwoven medium), a porous membrane, or another porous structure, such as ePTFE.

[0101] Example 3 is a filter medium according to Example 1 or 2, wherein the porous substrate includes a membrane.

[0102] Example 4 is a filter medium according to any one of Examples 1 to 3, wherein the compound comprises a metal conformally disposed on at least a portion of the reactive polymer.

[0103] Example 5 is a filter medium according to any one of Examples 1-4, wherein the compound includes M. n X m M n O m M n N m M n S m M n C m Or M n R m , Where M is a metal X is a halogen, and R is a carbon-containing straight-chain, branched, or cyclic group, which may optionally be substituted by one or more heteroatoms. n is an integer from 1 to 4, 1 to 3, 1 to 2, or 1, and m is an integer from 1 to 6, 1 to 5, 1 to 4, 1 to 3, 1 to 2, or 1.

[0104] Example 6 is a filter medium according to any one of Examples 1-5, wherein R is an alkyl, alkylene, or substituted alkyl or alkylene, such as an alkoxide group, an alkylamine group, or an alkylamide group.

[0105] Example 7 is a filter medium according to any one of Examples 1-6, wherein R includes acetylacetonate, cyclopentadienyl, butanol, ethanol, methanol, propanol, methylamino, ethylamino, or ethylmethylamino.

[0106] Example 8 is a filter medium according to any one of Examples 1-7, wherein the metal M includes aluminum, calcium, copper, erbium, gallium, hafnium, iridium, lanthanum, magnesium, palladium, platinum, niobium, ruthenium, scandium, silicon, strontium, tantalum, titanium, vanadium, yttrium, ytterbium, zinc, zirconium, or a combination of two or more thereof.

[0107] Example 9 is a filter medium according to any one of Examples 1-8, wherein the non-reactive base polymer includes polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), expanded polyethylene, expanded polypropylene, sulfonated tetrafluoroethylene, polyvinyl fluoride, oleophobic polyethersulfone, polypropylene, polyethylene, ethylene-vinyl acetate, polydimethylsiloxane, chloroprene rubber, polyisobutylene, polymethyl vinyl ether, polybutadiene, polypropylene glycol, or mixtures or copolymers of two or more thereof.

[0108] Example 10 is a filter medium according to any one of Examples 1-9, wherein the non-reactive base polymer includes an oleophobic polymer or an oleophobic processed product or both.

[0109] Example 11 is a filter medium according to any one of Examples 1-10, wherein the reactive polymer includes polyvinyl alcohol (PVOH), polymethyl methacrylate (PMMA), polyacrylic acid (PAA), polyhydroxyethyl methacrylate (pHEMA), poly(caprolactam), polyethylene terephthalate (PET), polyethylene glycol (PEG), polysulfone (PS), polyacrylonitrile (PAN), polyacrylamide (PAM), or any combination of two or more thereof.

[0110] Example 12 is a filter medium according to any one of Examples 1-11, wherein the reactive polymer includes polyvinyl alcohol (PVOH).

[0111] Example 13 is a filter medium according to any one of Examples 1-12, wherein the filter medium comprises 1 wt% or more, 2 wt% or more, 5 wt% or more, 10 wt% or more, 15 wt% or more, or 20 wt% or more of a metal compound, as measured by the TGA test method.

[0112] Example 14 is a filter medium according to any one of Examples 1-13, wherein the filter medium has a density of 0.02 cm. 3 / s / cm 2 Or larger, 0.05cm 3 / s / cm 2 Or larger, 0.1cm 3 / s / cm 2 Or larger, 0.2cm 3 / s / cm 2 Or larger, 0.3cm 3 / s / cm 2 Or larger, or 0.5 cm 3 / s / cm 2 Or even higher permeability. The permeability of filter media 10 and 110 can be 2 cm.3 / s / cm 2 Or smaller, 1.5 cm 3 / s / cm 2 Or smaller, 1.0 cm 3 / s / cm 2 Or smaller, or 0.8 cm 3 / s / cm 2 Or smaller.

[0113] Example 15 is a filter medium according to any one of Examples 1-14, wherein the filter medium includes a first main surface and an opposing second main surface and a thickness between the first main surface and the second main surface, and wherein, as determined by elemental analysis of a cross-section of the filter medium, 20 wt% or more of a metal-containing compound is placed within the thickness.

[0114] Example 16 is a filter medium according to any one of Examples 1-15, wherein at least 20 wt% of the compound is distributed throughout the thickness.

[0115] Example 17 is a filter medium according to any one of Examples 1-16, wherein the filter medium includes a plurality of regions comprising the reactive polymer.

[0116] Example 18 is a filter medium according to any one of Examples 1-17, wherein the filter medium includes a plurality of regions comprising the compound.

[0117] Example 19 is a filter medium according to any one of Examples 1-18, wherein the fibrous porous substrate comprises an expandable non-reactive base polymer.

[0118] Example 20 is a filter medium according to any one of Examples 1-19, wherein the non-reactive base polymer includes expanded polytetrafluoroethylene (ePTFE), expanded polyethylene, or expanded polypropylene, preferably wherein the non-reactive base polymer includes ePTFE.

[0119] Example 21 is a filter comprising a housing and a filter medium according to any one of Examples 1-20 disposed within the housing.

[0120] Example 22 is a filter according to any one of Examples 1-21, wherein the housing includes an inlet and an outlet and a fluid flow path extending from the inlet to the outlet and extending through or across the filter media.

[0121] Example 23 is a method for separating substances, the method comprising: The filter medium according to any one of Examples 1-22 is exposed to a fluid containing a substance and the substance is captured on the filter medium.

[0122] Example 24 is the method according to Example 23, wherein the method further includes removing the substance from the filter medium to regenerate the filter medium.

[0123] Example 25 is the method according to Example 23 or 24, wherein the substance includes a contaminant.

[0124] Example 26 is a method for manufacturing a filter medium according to any one of Examples 1-22, the method comprising: Contacting at least a portion of a non-reactive base polymer with a mixture to form a coated base polymer, said mixture comprising: Reactive polymers; and carrier; and A compound comprising a metal is placed on at least a portion of a base polymer coated thereon to form a filter media.

[0125] Example 27 is the method according to Example 26, wherein the non-reactive base polymer is wettable, and the method further includes contacting at least a portion of the non-reactive base polymer with a wetting liquid.

[0126] Example 28 is the method according to Example 26 or 27, wherein the non-reactive base polymer includes polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), sulfonated tetrafluoroethylene, polyvinyl fluoride, oleophobic polyethersulfone (e.g., PES coated with an oleophobic coating), polypropylene, nonwoven polypropylene, polyethylene, ethylene-vinyl acetate, polydimethylsiloxane, chloroprene rubber, polyisobutylene, polymethyl vinyl ether, polybutadiene, polypropylene glycol, any combination of two or more of these (including mixtures and copolymers), nonwoven materials made therefrom, and films made therefrom. In some embodiments, the non-reactive material (e.g., polymer) includes an oleophobic polymer or an oleophobic processed product or both. The wetting liquid includes isopropanol, acetone, ethanol, ethylamine, ethylene glycol, acetonitrile, methanol, 1-propanol, or pyridine.

[0127] Example 29 is a method according to any one of Examples 26-28, wherein the method further comprises crosslinking a reactive polymer, a non-reactive base polymer, or both onto which a base polymer has been coated.

[0128] Example 30 is the method according to any one of Examples 26-29, wherein crosslinking further comprises exposing the coated base polymer to a high temperature for a period of time.

[0129] Example 31 is the method according to any one of Examples 26-30, wherein the mixture further comprises a crosslinking agent.

[0130] Example 32 is the method according to any one of Examples 26-31, wherein placing the compound further includes using chemical vapor deposition.

[0131] Example 33 is the method according to any one of Examples 26-32, wherein chemical vapor deposition includes atomic layer deposition.

[0132] Example 34 is a method according to any one of Examples 26-33, wherein the porous substrate includes a fibrous porous web (e.g., a nonwoven medium), a porous membrane, or another porous structure, such as ePTFE.

[0133] Example 35 is the method according to any one of Examples 26-34, wherein the porous substrate comprises a membrane.

[0134] Example 36 is the method according to any one of Examples 26-35, wherein the compound comprises a metal conformally disposed on at least a portion of the reactive polymer.

[0135] Example 37 is the method according to any one of Examples 26-36, wherein the compound includes M. n X m M n O m M n N m M n S m M n C m Or M n R m , Where M is a metal X is a halogen, and R is a carbon-containing straight-chain, branched, or cyclic group, which may optionally be substituted by one or more heteroatoms. n is an integer from 1 to 4, 1 to 3, 1 to 2, or 1, and m is an integer from 1 to 6, 1 to 5, 1 to 4, 1 to 3, 1 to 2, or 1.

[0136] Example 38 is the method according to any one of Examples 26-37, wherein R is an alkyl, alkylene, or substituted alkyl or alkylene, such as an alkoxide group, an alkylamine group, or an alkylamide group.

[0137] Example 39 is the method according to any one of Examples 26-38, wherein R includes acetylacetonate, cyclopentadienyl, butanol, ethanol, methanol, propanol, methylamino, ethylamino, or ethylmethylamino.

[0138] Example 40 is the method according to any one of Examples 26-39, wherein the reactive polymer includes polyvinyl alcohol (PVOH), polymethyl methacrylate (PMMA), polyacrylic acid (PAA), polyhydroxyethyl methacrylate (pHEMA), poly(caprolactam), polyethylene terephthalate (PET), polyethylene glycol (PEG), polysulfone (PS), polyacrylonitrile (PAN), polyacrylamide (PAM), or any combination of two or more thereof.

[0139] Example 41 is the method according to any one of Examples 26-40, wherein the reactive polymer comprises polyvinyl alcohol (PVOH).

[0140] Example 42 is the method according to any one of Examples 26-41, wherein the filter medium comprises 1 wt% or more, 2 wt% or more, 5 wt% or more, 10 wt% or more, 15 wt% or more, or 20 wt% or more of a metal compound, as measured by the TGA test method.

[0141] Example 43 is the method according to any one of Examples 26-42, wherein the filter medium has a density of 0.02 cm. 3 / s / cm 2 Or larger, 0.05 cm 3 / s / cm 2 Or larger, 0.1 cm 3 / s / cm 2 Or larger, 0.2 cm 3 / s / cm 2 Or larger, 0.3 cm 3 / s / cm 2 Or larger, or 0.5 cm 3 / s / cm 2 Or even higher permeability. The permeability of filter media 10 and 110 can be 2 cm. 3 / s / cm 2 Or smaller, 1.5cm 3 / s / cm 2 Or smaller, 1.0cm 3 / s / cm 2 Or smaller, or 0.8 cm 3 / s / cm 2 Or smaller.

[0142] Example 44 is a method according to any one of Examples 26-43, wherein the filter medium includes a first main surface and an opposing second main surface and a thickness between the first main surface and the second main surface, and wherein, as determined by elemental analysis of a cross-section of the filter medium, 20 wt% or more of the metal-containing compound is placed within the thickness.

[0143] Example 45 is the method according to any one of Examples 26-44, wherein at least 20 wt% of the compound is distributed throughout the thickness.

[0144] Example 46 is the method according to any one of Examples 26-45, wherein the filter medium comprises a plurality of regions comprising a reactive polymer.

[0145] Example 47 is a method according to any one of Examples 26-46, wherein the filter medium comprises a plurality of regions including the compound.

[0146] Example 48 is a method according to any one of Examples 26-47, wherein the fibrous porous substrate comprises an expandable non-reactive base polymer.

[0147] Example 49 is the method according to any one of Examples 26-48, wherein the non-reactive base polymer includes expanded polytetrafluoroethylene (ePTFE), expanded polyethylene, or expanded polypropylene, preferably wherein the non-reactive base polymer includes ePTFE.

[0148] Example 50 is the method according to any one of Examples 26-49, wherein the metal M includes aluminum, calcium, copper, erbium, gallium, hafnium, iridium, lanthanum, magnesium, palladium, platinum, niobium, ruthenium, scandium, silicon, strontium, tantalum, titanium, vanadium, yttrium, ytterbium, zinc, zirconium, or a combination of two or more thereof.

[0149] Example 51 is a filter medium according to any one of Examples 1-20, a filter according to Examples 21-22, or a method according to any one of Examples 26-50, wherein the compound includes Al2O3, CaO, CuO, Er2O3, Ga2O3, HfO2, La2O3, MgO, Nb2O5, Sc2O3, SiO2, Ta2O5, TiO2, vanadium acetylacetonate, cyclopentadienylvanadium, vanadium butoxide, vanadium ethanol, vanadium methanol, vanadium propoxide, vanadium tetraethanol, Y2O3, Yb2O3, ZnO, ZrO2, AlN, GaN, pentapentanyl(dimethylamino)tantalum, TiAlN, tetra(dimethylamino)titanium, tetra(ethylmethylamino)titanium, TaC, TiC, Ir, Pd, Pt, Ru, ZnS, SrS, CaF2, LaF3, MgF2, SrF2, or any combination of two or more thereof. Example

[0150] These examples are for illustrative purposes only and are not intended to unduly limit the scope of the appended claims. While the numerical ranges and parameters that set forth the broad scope of this disclosure are approximations, the values ​​set forth in particular examples are reported as precisely as possible. However, any numerical value inherently contains some error that is necessarily caused by the standard deviation found in its corresponding test measurement. At least, and without attempting to limit the application of the equivalence doctrine to the scope of the claims, each numerical parameter should be interpreted at least according to the number of significant figures reported and by applying ordinary rounding techniques.

[0151] Unless otherwise stated, all parts, percentages, ratios, etc. in the examples and remainder of the specification are by weight, and all reagents used in the examples are obtained or purchased from general chemical suppliers (e.g., Sigma-Aldrich Company, Saint Louis, MO; Carus, Peru, IL; Calgon Carbon, Moon Township, PA; Ultramet, Los Angeles, CA); or can be synthesized by conventional methods.

[0152] The following abbreviations may be used in the following examples: mL = milliliter, L = liter, m = meter, mm = millimeter, min = minute, s = second, cm = centimeter, μm = micrometer, kg = kilogram, g = gram, min = minute, s = second, h = hour, ℃ = degree Celsius, ℉ = degree Fahrenheit; wt% = weight percentage; M = molar concentration; and DI water = deionized water. Test method: Thermogravimetric analysis (TGA)

[0153] Thermogravimetric analysis according to ASTM-E1131-20 is used to measure the wt% of metallic compounds, as measured by TGA. Imaging using SEM / EDX

[0154] Visual and elemental images were generated using a JEOL JSM-5900LV scanning electron microscope (SEM) equipped with an E-DAX EDS Si / Li detector (EDX). A 1 cm × 5 cm rectangular sample was cut from the medium. The sample was mounted face up on a short column with a notched cross-section and imaged using the SEM. Permeability test

[0155] To measure the Frazer permeability of a filter medium, the volume of air flowing through a given region of a pressurized porous material at a given pressure can be measured using known methods (e.g., ASTM D737-18). Frazer permeability can be measured using a Frazer Permeability Tester, available from Frazer Precision Instrument Co. Inc., Gaithersburg, Maryland. Permeability can be measured in 0.6 in... 2 Measurements were taken on a circular test area. Fraser permeability is typically expressed as cfm / ft at a water pressure drop of 0.5". 2 The unit is given as (0.5" water pressure drop of 1 cfm / ft) 2 Equal to 0.5 cm below 125 Pa 3 / s / cm 2 ). Pore ​​testing

[0156] The filter media of this invention can be evaluated based on the pore structure of the media. The pore structure can be characterized based on capillary theory of pore measurement. Capillary theory of pore measurement relies on the assumption that a force balance exists between the hydrostatic head pressure of the liquid and the force from surface tension. The force balance of capillary forces in the pores can be calculated using the following equation derived from the Young-Laplace equation: ; Where σ (sigma) = surface tension; d = pipe diameter; θ (theta) = the contact angle of the liquid on the tube surface; γ (gamma) = the specific gravity of the fluid; Δh = Displacement distance of the fluid in the pipe; For wettable fluids, the contact angle is small, and we can assume that cos(θ)≈1; After replacing specific gravity and liquid height with pressure, the equation can be written as:

[0157] This equation involves diameter, pressure, and surface tension, and is used to calculate pore size in porosity testing.

[0158] Pore ​​size measurements were performed on each membrane according to ASTM D6767-21. This type of pore testing can be performed using an automated air permeability porosimeter, for example, manufactured by Porous Materials, Inc. As used herein, the model was an APP-1200-AEXSC using CAPWIN Version 6.71.122 testing software. The test procedure included capillary flow pore size analysis, drying / wetting with silicone oil and a fluid surface tension of 20.1 dynes / c. The effective test size of the sample had a diameter of 1.0 cm, a maximum air flow rate of 100,000 cc / min, and a maximum sample pressure differential of 120 kPa.

[0159] To calculate the pore size distribution from the data, the curves for the dry sample are compared with those for the wet sample. This can be done by calculating the percentage of airflow in the wet sample relative to the airflow in the dry sample. This yields the so-called filter flow rate percentage, which is a function of pressure. .

[0160] Using the capillary theoretical equation and replacing pressure with diameter, we obtain the flow rate baseline orifice size distribution curve from 0-100%: .

[0161] The raw data collected from the tests can be curve-fitted to a distribution format without having to restrict it to a classic normal distribution curve. The results of this technique are as follows: g(d) = cumulative distribution function of pore size diameter of the test sample; G(d) = Density distribution function of pore size diameter of the test sample. Water flux test

[0162] Water flux measurements are generated as follows: 5 gallons of water are added to a pressure vessel, pressurized to 10 psi, connected to a filter patch holder, and the valve between the vessel and the filter patch holder is opened. For all samples, the volume of water passing through the filter is captured in a calibrated cylinder and measured after 30 seconds. The filter patch has an effective area with a diameter of 47 mm. Water flux can be expressed as liters / m² / min / psi (L / m²). 2 The units are given as ( / min / psi). Example 1

[0163] Imaging of base material samples with and without a poly(vinyl alcohol) (PVOH) coating. The base material was an ePTFE membrane sheet purchased from Donaldson Company in Bloomington, MN as Tx1303. The membrane was coated with PVOH using methods known to those skilled in the art, including pre-wetting the membrane with a solvent, immersing the membrane in a PVOH solution, and rinsing the membrane.

[0164] Visual images were generated using a JEOL JSM-5900LV scanning electron microscope. The SEM images are shown in... Figure 3A In (uncoated sample) and 3B (PVOH coated sample). Example 2

[0165] The base material Tx1303 was treated with Al2O3 by atomic layer deposition for 100 and 300 cycles. As described in Example 1, one set of samples was first coated with PVOH. Another set was treated with Al2O3 without a PVOH coating. Atomic layer deposition of Al2O3 on the base material was performed at 150°C and 1 mbar. Each cycle lasted 6 seconds, including 3 seconds for the initiator (water) and 3 seconds for the precursor (trimethylaluminum).

[0166] Visual and elemental images were generated using a JEOL JSM-5900LV scanning electron microscope. Fraser permeability of the filter media was measured using permeability testing. Pore structure was characterized using capillary theory based on porosimetry. Water flux was measured using water flux testing.

[0167] SEM images were obtained at a magnification of 15,000 × 10⁻⁶. SEM images of the nodules and fibrous portions of the sample are shown below: Figure 4A (Nodular portion) and 4C (fiber portion), which do not contain PVOH, undergo 100 Al2O3 cycles; Figure 4B (Nodular portion) and 4D (fibrous portion), which contains PVOH, undergo 100 Al2O3 cycles; Figure 4E (Nodular portion) and 4G (fiber portion), which do not contain PVOH, undergo 300 Al2O3 cycles; Figure 4F (Nodular portion) and 4H (fibrous portion), containing PVOH, were subjected to 300 Al2O3 cycles. Pore analysis results (and the sample from Example 3) are shown in... Figure 5A (Without PVOH) and 5B (with PVOH); water flux results are shown in Figure 6A (without PVOH) and 6B (with PVOH); and elemental analysis (EDX) results are shown in Figure 7 middle.

[0168] It was observed that the samples treated with PVOH appeared more yellow than the untreated samples. Example 3

[0169] The base material Tx1303 was treated with TiO2 by atomic layer deposition for 150 and 500 cycles. As described in Example 1, one set of samples was first coated with PVOH. Another set was treated with TiO2 without a PVOH coating. ALD deposition of TiO2 on the base material was performed at 150°C and 1 mbar. Each cycle lasted 6 seconds, including 3 seconds for the initiator (water) and 3 seconds for the precursor (tetra(dimethylamino)titanium(IV)).

[0170] Visual and elemental images were generated using a JEOL JSM-5900LV scanning electron microscope. The Fraser permeability of the filter media was measured using permeability testing. The pore structure of the filter media of the present invention was characterized based on capillary theory using porosimetry. The water flux of the present invention was measured using water flux testing.

[0171] SEM images were obtained at a magnification of 15,000 × 10⁻⁶. SEM images of the nodules and fibrous portions of the sample are shown below: Figure 8A (Nodular portion) and 8C (fiber portion), which do not contain PVOH, are subjected to 150 TiO2 cycles; Figure 8B (Nodular portion) and 8D (fiber portion), which contain PVOH, undergo 150 TiO2 cycles; Figure 8E (Nodular portion) and 8G (fiber portion), which do not contain PVOH, are subjected to 500 TiO2 cycles; Figure 8F (Nodular portion) and 8H (fibrous portion), containing PVOH, were subjected to 500 TiO2 cycles. Permeability results are shown in... Figure 9A and 9B The elemental analysis (EDX) results are shown in... Figure 10 In, and the TGA results are shown in Figure 11 middle.

[0172] It has been observed that adding a high surface energy coating (e.g., PVOH) to materials such as PTFE can significantly alter the absorption rate of metal oxides. This disclosure provides that a polyvinyl alcohol (PVOH) coating increases the absorption rate of both Al2O3 and TiO2 coatings on ePTFE. Samples without a PVOH coating exhibit more nodular growth, indicating low activity on the polymer surface. For the treated samples, smoother fibers are observed, indicating better coverage. TGA results confirm that the increased pick-up is due to differences in ash content and differences observed in EDX data. Samples pre-treated with PVOH were observed to appear grayer than untreated samples.

[0173] All references and publications cited herein are expressly incorporated in their entirety unless they may directly contradict this disclosure. While specific embodiments have been illustrated and described herein, those skilled in the art will understand that various alternative and / or equivalent embodiments may be substituted for the specific embodiments shown and described without departing from the scope of this disclosure. It should be understood that this disclosure is not intended to be unduly limited by the illustrative embodiments and examples set forth herein, and such examples and examples are presented by way of example only, while the scope of this disclosure is intended to be limited only by the claims set forth herein.

Claims

1. A filter medium comprising: a porous substrate comprising a non-reactive base polymer; a reactive polymer disposed on at least a portion of the base polymer, the reactive polymer having a surface energy higher than a surface energy of the non-reactive base polymer; and a compound comprising a metal disposed on at least a portion of the reactive polymer.

2. The filter medium of claim 1, wherein the porous substrate comprises a fibrous porous web.

3. The filter medium of claim 1, wherein the porous substrate comprises a membrane.

4. The filter medium of any one of claims 1 to 3, wherein the compound comprises a metal conformally disposed on at least a portion of the reactive polymer.

5. The filter media of any of claims 1-4, wherein the compound comprises M n X m , M n O m , M n N m , M n S m , M n C m , or M n R m , wherein M is a metal, X is a halogen, and R is a carbon-containing linear, branched, or cyclic group, optionally substituted with one or more heteroatoms, n is an integer from 1 to 4, and m is an integer from 1 to 6.

6. The filter medium of any one of claims 1 to 5, wherein the non-reactive base polymer comprises polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), expanded polyethylene, expanded polypropylene, sulfonated tetrafluoroethylene, polyvinyl fluoride, oleophobic polyether sulfone, polypropylene, polyethylene, ethylene-vinyl acetate, polydimethylsiloxane, neoprene, polyisobutylene, polymethyl vinyl ether, polybutadiene, polypropylene glycol, or a mixture or copolymer of two or more thereof.

7. The filter medium of any one of claims 1 to 6, wherein the non-reactive base polymer comprises an oleophobic polymer or an oleophobic finish or both.

8. The filter medium of any one of claims 1 to 7, wherein the reactive polymer comprises polyvinyl alcohol (PVOH), polymethyl methacrylate (PMMA), polyacrylic acid (PAA), polyhydroxyethyl methacrylate (pHEMA), polycaprolactam, polyethylene terephthalate (PET), polyethylene glycol (PEG), polysulfone (PS), polyacrylonitrile (PAN), polyacrylamide (PAM), or any combination of two or more thereof.

9. The filter medium of any one of claims 1 to 8, wherein the filter medium comprises 2 wt% or more of the compound of the metal as measured by the TGA test method.

10. The filter media of any of claims 1-8, wherein the filter media has a permeability of 0.02 cm 3 / s / cm 2 or more.

11. The filter medium of any one of claims 1 to 10, wherein the filter medium comprises a first major surface and an opposing second major surface and a thickness between the first major surface and the second major surface, and wherein 20 wt% or more of the compound comprising the metal is disposed within the thickness as determined by elemental analysis of a cross-section of the filter medium.

12. The filter medium of claim 11, wherein at least 20 wt% of the compound is distributed throughout the thickness.

13. The filter medium of any one of claims 1 to 11, wherein the filter medium comprises a plurality of regions comprising the reactive polymer.

14. The filter media of any of claims 1-11, wherein the filter media comprises a plurality of regions comprising a compound.

15. The filter media of any of claims 1-14, wherein the fibrous porous substrate comprises an intumescent non-reactive base polymer.

16. A filter comprising a housing and a filter media according to any of claims 1-15 disposed therein.

17. A method of separating a substance, the method comprising: exposing a filter media according to any of claims 1-16 to a fluid comprising the substance and capturing the substance on the filter media.

18. The method of claim 17, wherein the method further comprises removing the substance from the filter media to regenerate the filter media.

19. The method of claim 17 or 18, wherein the substance comprises a contaminant.

20. A method of making a filter media according to any of claims 1-15, the method comprising: contacting at least a portion of a non-reactive base polymer with a mixture to form a coated base polymer, the mixture comprising: a reactive polymer; and a carrier; and placing a compound comprising a metal on at least a portion of the coated base polymer to form the filter media.

21. The method of claim 20, wherein the non-reactive base polymer is wettable, and the method further comprises contacting at least a portion of the non-reactive base polymer with a wetting liquid.

22. The method of claim 21, wherein the non-reactive base polymer comprises polytetrafluoroethylene, and the wetting liquid comprises isopropyl alcohol.

23. The method of any of claims 20-22, wherein the method further comprises crosslinking the reactive polymer, the non-reactive base polymer, or both, of the coated base polymer.

24. The method of claim 23, wherein crosslinking further comprises exposing the coated base polymer to an elevated temperature for a period of time.

25. The method of claim 23 or 24, wherein the mixture further comprises a crosslinking agent.

26. The method of any of claims 20-25, wherein placing the compound further comprises using chemical vapor deposition.

27. The method of claim 26, wherein the chemical vapor deposition comprises atomic layer deposition.

28. The filter media of claim 5, wherein the metal M comprises aluminum, calcium, copper, erbium, gallium, hafnium, iridium, lanthanum, magnesium, palladium, platinum, niobium, ruthenium, scandium, silicon, strontium, tantalum, titanium, vanadium, yttrium, ytterbium, zinc, zirconium, or a combination of two or more thereof.

29. The filter media of any of claims 1 to 15, the filter of claim 16, or the method of any of claims 17 to 27, wherein the compound comprises AI2O3, CaO, CuO, Er2O3, Ga2O3, HfO2, La2O3, MgO, Nb2O5, Sc2O3, SiO2, Ta2O5, TiO2, vanadyl acetylacetonate, vanadyl cyclopentadienyl, vanadyl butoxide, vanadyl ethoxide, vanadyl methoxide, vanadyl propoxide, vanadyl tetraethoxide, Y2O3, Yb2O3, ZnO, ZrO2, AIN, GaN, pentakis(dimethylamino)tantalum, TiAIN, tetra(dimethylamino)titanium, tetra(ethylmethylamino)titanium, TaC, TiC, Ir, Pd, Pt, Ru, ZnS, SrS, CaF2, LaF3, MgF2, SrF2, or a combination of any two or more thereof.

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