Porous substrate comprising a PTFE composition

Abstract

A porous substrate having a composition disposed thereon and a method for disposing a composition on a porous substrate, the composition comprising a matrix, the matrix comprising a plurality of polytetrafluoroethylene fibrils and a plurality of active particles.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 429,959, filed December 2, 2022, which is incorporated herein by reference in its entirety. [Background technology]

[0002] Catalysts and adsorbents (adsorbents and absorbents) can be used to remove undesirable chemicals from fluids (e.g., gases or liquids). For example, catalysts can be used to destroy chemicals such as ozone or to synthesize desired chemical species from reactant feedstocks. Adsorbents can be used to separate or remove acidic molecules, basic molecules, ozone, or various other organic or inorganic compounds from fluids. Catalysts and adsorbents can be difficult to handle when in powder or particulate form. Therefore, catalysts and adsorbents are often immobilized on a support. While immobilizing a catalyst or adsorbent on a support may facilitate handling of the catalyst or adsorbent, immobilizing the catalyst or adsorbent on a support may reduce the surface area of ​​the catalyst or adsorbent available for removing undesirable chemicals from a fluid. Furthermore, the physical and chemical properties of the support can affect the functionality of the catalyst (e.g., catalytic efficiency) or adsorbent. Furthermore, the physical and chemical properties of the support can affect the final configuration of a product (e.g., a filter) containing the catalyst or adsorbent-functionalized support. Ideally, a catalyst or adsorbent functionalized support has one or more of the following properties: it is easily fabricated; it has the catalyst or adsorbent immobilized in a configuration that provides a large catalyst or adsorbent surface area; and it is resistant to mechanical and chemical degradation.

[0003] Disclosure Overview The present disclosure provides a porous substrate having a composition disposed thereon. The composition comprises a matrix including a plurality of PTFE fibrils and a plurality of active particles. In some embodiments, the plurality of PTFE fibrils comprises short-chain PTFE fibrils and long-chain PTFE fibrils. In some embodiments, the composition further comprises free active particles, free PTFE fibrils, or both. In some embodiments, the plurality of active particles, the free active particles (if present), or both comprise a catalyst, an adsorbent, a growth seed, a metal-organic framework (MOF), or a combination thereof.

[0004] In some embodiments, the porous substrate comprises a major surface and a plurality of macropores communicating with the major surface. In some such embodiments, a first portion of the composition is disposed on at least a portion of the major surface, and at least a portion of the plurality of macropores is impregnated with a second portion of the composition. In some embodiments, the porous substrate further comprises a third portion of the composition embedded within the porous substrate.

[0005] Disclosed is a method of disposing a composition onto a porous substrate to obtain the porous substrate of any one of the preceding embodiments.

[0006] The terms "short-chain PTFE fibrils" and "long-chain PTFE fibrils" are used in conjunction with one another. Short-chain PTFE fibrils have a shorter length than long-chain PTFE fibrils as measured by the Dimensional Analysis Test Method. A plurality of short-chain PTFE fibrils have an average length that is shorter than the average length of a plurality of long-chain PTFE fibrils as measured according to the Dimensional Analysis Test Method. The fibril length is the largest dimension of the fibril. Short-chain PTFE fibrils and long-chain PTFE fibrils are formed from PTFE starting materials that differ in average PTFE resin size.

[0007] As used herein, the term "active particle" refers to a particle that includes at least one component that can participate in a chemical reaction (e.g., as a catalyst) and / or act as an adsorbent and / or absorbent.

[0008] As used herein, the term "comprises" and variations thereof do not have a limiting meaning when these terms appear in the description and claims. Such terms will be understood to mean the inclusion of the recited steps or elements, or group of steps or elements, but not the exclusion of any other steps or elements, or group of steps or elements. The phrase "consisting of" means inclusive and limited to what follows the phrase "consisting of." Thus, the phrase "consisting of" indicates that the recited elements are necessary or essential, and that no other elements may be present. The phrase "consisting essentially of" means including any elements listed after the phrase, and is limited to other elements that do not interfere with or contribute to the activity or function specified in this disclosure for the recited elements. Thus, the phrase "consisting essentially of" indicates that the recited elements are necessary or essential, but that other elements are optional and may or may not be present depending on whether they substantially affect the activity or function of the recited elements. Any element or combination of elements described herein in an open-ended language (e.g., comprise and its derivatives) is considered to be further described in closed-ended language (e.g., consist of and its derivatives) and partially closed-ended language (e.g., consist essentially of and its derivatives).

[0009] The words "preferred" and "preferably" refer to embodiments of the present disclosure that may offer certain benefits, under particular circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the present disclosure.

[0010] In this application, terms such as "a," "an," and "the" are not intended to refer only to a singular entity, but include a general class of which a particular example may be used for illustration. The terms "a," "an," and "the" are used interchangeably with the term "at least one." The phrases "at least one of" and "comprises at least one of" following a list refer to any one of the items in the list, and any combination of two or more items in the list.

[0011] As used herein, the term "or" is generally used in its ordinary sense, including "and / or," unless the content clearly dictates otherwise.

[0012] The term "and / or" means one or all of the listed elements or a combination of any two or more of the listed elements.

[0013] Also, all numerical values ​​herein are assumed to be modified by the term "about," and in certain embodiments, preferably, by the term "exactly." When used herein in connection with a measured quantity, the term "about" refers to the variation of that measured quantity that is expected by one of ordinary skill in the art making the measurement and exercising a level of care commensurate with the purpose of the measurement and the precision of the measuring equipment used. At the very least, and not as an attempt to limit the scope of the claims to the doctrine of equivalents, each numerical parameter should, at the very least, be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0014] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible, however, all numerical values ​​inherently contain ranges necessarily resulting from the standard deviation found in their respective testing measurements.

[0015] As used herein, "up to" a number (e.g., up to 50) includes that number (e.g., 50). As used herein, "at least" a number (e.g., at least 50) includes that number (e.g., 50). As used herein, "up to or equal to" a number (e.g., up to 50) includes that number (e.g., 50).

[0016] Also herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range, as well as the endpoints (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

[0017] As used herein, the term "room temperature" or "ambient temperature" refers to a temperature between 20°C and 25°C.

[0018] The terms "in the range" or "within the range" (and similar descriptions) include the endpoints of the stated range.

[0019] Throughout this specification, references to "one aspect," "an aspect," "aspects," "one embodiment," "an embodiment," "particular embodiments," "some embodiments," or "one or more embodiments" or the like mean that the particular feature, configuration, composition, or characteristic described in connection with an embodiment or aspect is included in at least one embodiment or aspect of the disclosure. Thus, the appearances of such phrases in various places throughout this specification do not necessarily refer to the same embodiment or aspect of the disclosure. Furthermore, particular features, configurations, compositions, or characteristics may be combined in any suitable manner in one or more embodiments or aspects.

[0020] The term "on," when used in the context of a composition or hydrated solid disposed on a surface or substrate, includes both a composition or hydrated solid disposed (e.g., applied) directly or indirectly (e.g., on a primer layer) on the surface or substrate. Thus, for example, a composition or hydrated solid disposed on a pretreatment layer or primer layer covering a substrate constitutes a composition or hydrated solid disposed on the substrate.

[0021] The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The following description more particularly exemplifies exemplary embodiments. In several places throughout this disclosure, guidance is provided through lists of examples, which examples can be used in various combinations. In each instance, the recited list serves only as a representative group and should not be interpreted as an exclusive or exhaustive list. Thus, the scope of the disclosure should not be limited to the specific exemplary structures described herein, but should extend to at least the structures recited by the language of the claims and equivalents of those structures. Any of the elements affirmatively recited herein as alternatives can also be expressly included in or excluded from the claims, in any combination as appropriate. While various theories and possible mechanisms have been discussed herein, such discussion should not in any way serve to limit the claimable subject matter.

[0022] The complete disclosures of all patents, patent applications, publications, and electronically available materials cited herein are incorporated by reference in their entirety. In the event of a conflict between this disclosure and the disclosure of any document incorporated herein by reference, the present disclosure shall control. The foregoing detailed description and examples are given for clarity of understanding only. No unnecessary limitations should be understood therefrom. The invention is not limited to the exact details shown and described, for variations obvious to one skilled in the art are within the scope of the invention as defined by the claims.

[0023] All headings are for the convenience of the reader and should not be used to limit the meaning of the text that follows the heading, unless specifically stated. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a schematic diagram of an exemplary matrix at two magnifications. [Figure 2]Figure 2A is a schematic diagram of a short-chain PTFE fibril, and Figure 2B is a schematic diagram of a long-chain PTFE fibril. [Figure 3] Figure 3A is a schematic diagram of a catenation structure of a plurality of active particles around a fibril of the matrix of Figure 1. Figure 3B is a schematic diagram of an agglomeration structure including a portion of the plurality of active particles and a portion of the plurality of fibrils of the matrix of Figure 1. [Figure 4] FIG. 4 is a schematic illustration of a porous substrate having a composition and / or one or more components of the composition disposed thereon and impregnated therein. [Figure 5] FIG. 5 is a schematic diagram illustrating embedding of particles within the solid portion of a porous substrate. [Figure 6] FIG. 6 is a flow chart outlining a first method of making a composition and / or coating a substrate with a composition, which methods are consistent with embodiments of the present disclosure. [Figure 7] FIG. 7 is a flow chart outlining a second method of making the composition and / or coating a substrate with the composition, which methods are consistent with embodiments of the present disclosure. [Figure 8] FIG. 8 is a flow chart outlining a method for drying a hydrated composition to form a matrix, consistent with embodiments of the present disclosure. [Figure 9] 9 is a first scanning electron micrograph of a matrix consistent with the present disclosure. The matrix contained 40 wt% K2CO3, 8.6 wt% PTFE-12, and 51.4 wt% PTFE-E. Image information: working distance (WD) = 4.0 mm; 5.0 kV LED; ×11,000. [Figure 10] 10 is a second scanning electron micrograph of a matrix consistent with the present disclosure. The matrix contained 68.9 wt% CARULITE, 15.5 wt% PTFE-E, and 15.5 wt% PTFE-12. Image information: WD=4.9 mm; 5.0 kV LED; ×370. [Figure 11]11 is a third scanning electron micrograph of a matrix consistent with the present disclosure. The matrix contained 68.9 wt. % Karlite, 15.5 wt. % PTFE-E, and 15.5 wt. % PTFE-12. Image information: WD=7.2 mm; 5.0 kV LED; ×3,500. [Figure 12] 12 is a fourth scanning electron micrograph of a matrix consistent with the present disclosure. The matrix contained 68.9 wt. % Karlite, 15.5 wt. % PTFE-E, and 15.5 wt. % PTFE-12. Image information: WD=7.5 mm; 5.0 kV LED; ×1,100. [Figure 13] 13A and 13B show electron micrographs of a surface coating of a polyurethane substrate with a composition including KCO particles, CSAC particles, long-chain PTFE fibrils, and short-chain PTFE fibrils after deposition under vacuum. Image information for 13A: WD=4.8 mm; 5.0 kV LED; ×130. Image information for 13B: WD=3.9 mm; 5.0 kV LED; ×2300. [Figure 14] Figures 14A and 14B show cross-sectional SEM images of the polyurethane substrate of Figures 13A and 13B. Image information for 14A: WD = 3.4 mm; 5.0 kV LED; × 170. Image information for 14B: WD = 3.4 mm; 5.0 kV LED; × 8000. [Figure 15] FIG. 15 is a plot showing H2S breakthrough performance across the substrates of FIGS. 16 and 17 at 25° C., 100-300 cm3 / min, and 25 ppm. [Figure 16] 16A and 16B show images of the major surface of a PU-15 substrate exposed by the method of depositing the composition with (16A) and without (16B) treatment in an ethanol bath. [Figure 17] Figure 17 shows electron micrographs comparing the surface of a PU-15 substrate on which compositions were applied using this method without (17A) and with (17B) ethanol as a wetting agent. Image information for 17A: WD = 4.2 mm; 5.0 kV LED; × 4,300. Image information for 17B: WD = 6.4 mm; 5.0 kV LED; × 19,000. [Figure 18] Figure 18 compares the surface integrity of polyurethane substrates coated with compositions containing KCO / CSAC, PTFE-E only (18A-18B), or both PTFE-E and PTFE-12 (18C-18D). Image information for 18A: WD = 5.9 mm; 5.0 kV LED; ×190. Image information for 18B: WD = 6.7 mm; 5.0 kV LED; ×11,000. Image information for 18C: WD = 6.6 mm; 5.0 kV LED; ×37. Image information for 18D: WD = 6.4 mm; 5.0 kV LED; ×6,000.

[0025] DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS The present disclosure provides porous substrates having compositions disposed thereon, and methods for disposing such compositions on such substrates. The compositions of the present disclosure include a matrix comprising a plurality of PTFE fibrils and a plurality of active particles. In some embodiments, the composition may further comprise free active particles, free PTFE fibrils, or both.

[0026] Disposing a composition on a porous substrate includes disposing such a composition on a major surface of the substrate; impregnating the substrate with such a composition or one or more components of the composition (e.g., free active particles, free PTFE fibrils, a matrix, or any combination thereof); embedding such a composition or one or more components within the substrate; or any combination thereof. Thus, a porous substrate of the present disclosure may have the composition disposed on at least a portion of a major surface; may be impregnated with the composition and / or one or more components of the composition; may have the composition and / or one or more components embedded therein; or any combination thereof.

[0027] composition The compositions of the present disclosure include a matrix. The matrix of the present disclosure includes a plurality of PTFE fibrils and a plurality of active particles. In some embodiments, the compositions can further include free active particles, free PTFE fibrils, or both.

[0028] Multiple polytetrafluoroethylene (PTFE) fibrils The compositions of the present disclosure include a matrix. The matrix of the present disclosure includes a plurality of PTFE fibrils. The fibrils can include a single chain of PTFE or multiple chains of PTFE. In some embodiments, the fibrils are arranged in a fibrous structure; i.e., multiple, ordered PTFE chains are arranged in the same general direction.

[0029] The PTFE fibrils are formed from PTFE resin. The PTFE resin may include a PTFE polymer, oligomer, monomer, or any combination thereof. The PTFE resin may be solid or liquid. The PTFE resin may be an emulsion. The PTFE resin includes particles including a PTFE polymer, oligomer, monomer, or any combination thereof. Each particle of the PTFE resin has a resin particle size. The resin particle size is defined as the maximum distance between resin particles.

[0030] In some embodiments, the plurality of PTFE fibrils is a single type of PTFE fibrils, such as short-chain PTFE fibrils or long-chain PTFE fibrils. In some embodiments, the matrix of the present disclosure comprises short-chain PTFE fibrils (formed from short-chain PTFE resin) and long-chain PTFE fibrils (formed from long-chain PTFE resin).

[0031] 2A shows a schematic diagram of a short chain PTFE fibril 30. The short chain PTFE fibril has a length 31 and a diameter 32. The length of a PTFE fibril (short or long) is the distance spanning the largest dimension of the fibril. The diameter of a PTFE fibril (short or long) is the largest distance spanning the smallest dimension of the fibril.

[0032] The short-chain PTFE fibrils are formed from short-chain PTFE resins. The short-chain PTFE resins can be obtained or formed as emulsions with dispersants (e.g., water and / or organic solvents) and / or surfactants. As used herein, the use of short-chain PTFE resins includes the use of resins and / or short-chain PTFE emulsions with dispersants and / or surfactants. In some embodiments, short-chain PTFE resins, such as those used to form the short-chain PTFE fibrils of the matrix of the present disclosure, have an average resin particle size of 1 μm to 9 μm, preferably 3 μm to 5 μm, as measured according to a dimensional analysis test method. When the short-chain PTFE resin is incorporated into the matrix of the present disclosure (e.g., using the method of the present disclosure), the resin particles of the short-chain PTFE resin elongate (e.g., fibrillate) to form short-chain PTFE fibrils.

[0033] In some embodiments, the short-chain PTFE fibrils of the matrix have an average length of 30 μm or less (to 1 μm), preferably 20 μm or less (to 1 μm), 10 μm or less (to 1 μm), or 5 μm or less (to 1 μm), as measured according to the Dimensional Analysis Test Method. In one embodiment, the short-chain PTFE fibrils of the matrix have an average length of 30 μm or less (to 1 μm), preferably 20 μm or less (to 1 μm), 10 μm or less (to 1 μm), or 5 μm or less (to 1 μm), as measured according to the Dimensional Analysis Test Method. In some embodiments, the short-chain PTFE fibrils of the matrix have an average diameter of 0.01 μm or more, 0.05 μm or more, 0.3 μm or more, or 0.5 μm or more, as measured according to the Dimensional Analysis Test Method. In some embodiments, the short chain PTFE fibrils of the matrix have an average diameter of 1 μm or less, 0.5 μm or less, or 0.3 μm or less, as measured according to a Dimensional Analysis Test Method.

[0034] The short chain PTFE fibrils of the matrix are generally not well ordered (see, eg, Figure 8 and discussion elsewhere herein).

[0035] 2B shows a schematic diagram of a long-chain PTFE fibril 20. The long-chain PTFE fibril 20 has a diameter 23 and a length 24. In some embodiments, the long-chain PTFE fibril 20 is composed of a plurality of constituent PTFE fibrils 22. The plurality of constituent PTFE fibrils 22 are generally aligned in the same direction to form the long-chain PTFE fibril structure. In this manner, the long-chain PTFE fibril can be considered a fiber in that it is composed of constituent fibrils that are generally aligned in a single direction. The plurality of constituent PTFE fibrils 22 differ from short-chain PTFE fibrils at least because the constituent PTFE fibrils 22 have a longer average length than the short-chain PTFE fibrils. In some embodiments, the long-chain PTFE fibrils (and thus the constituent PTFE fibrils) have an average length of 40 μm or more, 100 μm or more, 150 μm or more, 250 μm or more, 500 μm or more, 700 μm or more, or 1000 μm or more, as measured according to a Dimensional Analysis Test Method. In some embodiments, the long-chain PTFE fibrils have an average length of 2000 μm or less, 1000 μm or less, 700 μm or less, 500 μm or less, 250 μm or less, 150 μm or less, or 100 μm or less, as measured according to a Dimensional Analysis Test Method. The multiple constituent PTFE fibrils 22 need not directly interact, i.e., there may be spaces separating two or more constituent PTFE fibrils. Each constituent PTFE fibril of the multiple constituent PTFE fibrils 22 has a diameter narrower than the diameter of the long-chain PTFE fibrils 20. The diameter 23 of the long-chain PTFE fibrils is the sum of the thickness of each constituent PTFE fibril and the spaces between the constituent PTFE fibrils, if present. In some embodiments, the average diameter of the long-chain PTFE fibrils is 0.5 μm or more, 1 μm or more, 10 μm or more, or 50 μm or more. In some embodiments, the average diameter of the long-chain PTFE fibrils is 100 μm or less, 50 μm or less, 10 μm or less, or 1 μm or less, as measured according to the Dimensional Analysis Test Method. In some embodiments, the average diameter of the long-chain PTFE fibrils is 0.5 μm to 50 μm, preferably 1 μm to 50 μm, and more preferably 10 μm to 50 μm, as measured according to the Dimensional Analysis Test Method.

[0036] The long-chain PTFE fibrils are formed from the long-chain PTFE resin. In some embodiments, the long-chain PTFE resin has an average resin particle size of 10 μm or more, 25 μm or more, 50 μm or more, 100 μm or more, 200 μm or more, and up to 1000 μm, as measured according to a dimensional analysis test method. When the long-chain PTFE resin is incorporated into the matrix of the present disclosure (e.g., using the method of the present disclosure), the particles of the long-chain PTFE resin elongate (e.g., fibrillate) to form long-chain PTFE fibrils. Some examples of long-chain PTFE fibrils in the matrix of the present disclosure are shown in box 30 of Figure 9. Without wishing to be bound by theory, it is believed that the long-chain PTFE fibrils impart a degree of mechanical rigidity to the matrix, resulting in a membrane-like matrix.

[0037] Without wishing to be bound by theory, it is believed that particles of short-chain PTFE resin and particles of long-chain PTFE resin do not coalesce to form PTFE fibrils; that is, particles of long-chain PTFE resin form long-chain PTFE fibrils, and particles of short-chain PTFE resin form short-chain PTFE fibrils. Although short-chain PTFE fibrils may be located within long-chain PTFE fibrils, they are believed to be separate entities.

[0038] The average PTFE fibril diameter, average PTFE fibril length, and average resin particle size can be measured using a variety of methods, including microscopy such as scanning electron microscopy (SEM; see Dimensional Analysis Test Methods) or transmission electron microscopy (TEM).

[0039] In some embodiments, the compositions and / or matrices of the present disclosure comprise 5% by weight (wt%) or more, 15% by weight or more, 25% by weight or more, 45% by weight or more, 55% by weight or more, 65% by weight or more, or 80% by weight or more of a plurality of PTFE fibrils, calculated according to Compositional Analysis Test Methods, based on the total weight of the composition. In some embodiments, the compositions comprise 95% by weight or less, 80% by weight or less, 65% by weight or less, 55% by weight or less, 45% by weight or less, 25% by weight or less, or 15% by weight or less of a plurality of PTFE fibrils, calculated according to Compositional Analysis Test Methods, based on the total weight of the composition.

[0040] The ratio of short-chain PTFE fibrils to long-chain PTFE fibrils in the composition can vary depending on the desired end use of the composition. The ratio and weight percentage of short-chain PTFE fibrils to long-chain PTFE fibrils in the composition is defined as the mass of short-chain PTFE resin and the mass of long-chain PTFE resin used to make the matrix. In some embodiments, the weight ratio of short-chain PTFE fibrils to long-chain PTFE fibrils can be 5 parts to 1 part short-chain PTFE fibrils for every 0.1 part long-chain PTFE fibrils, preferably 3 parts to 1 part short-chain PTFE fibrils for every 0.1 part long-chain PTFE fibrils.

[0041] In other words, the total amount of PTFE in the matrix (i.e., the sum of short-chain PTFE fibrils and long-chain PTFE fibrils) can contain various weight percentages of short-chain PTFE fibrils and long-chain PTFE fibrils. In some embodiments, the composition contains 0.1 wt.% or more, 1 wt.% or more, 5 wt.% or more, 15 wt.% or more, 25 wt.% or more, 45 wt.% or more, 55 wt.% or more, 65 wt.% or more, or 80 wt.% or more short-chain PTFE fibrils, calculated according to the Compositional Analysis Test Methods, based on the total weight of the composition. In some embodiments, the composition contains 95 wt.% or less, 80 wt.% or less, 65 wt.% or less, 55 wt.% or less, 45 wt.% or less, 25 wt.% or less, 15 wt.% or less, 5 wt.% or less, or 1 wt.% or less short-chain PTFE fibrils, calculated according to the Compositional Analysis Test Methods, based on the total weight of the composition. In some embodiments, the composition comprises 0.01 wt% or more, 1 wt% or more, 5 wt% or more, 10 wt% or more, 15 wt% or more, 20 wt% or more, 30 wt% or more, or 40 wt% or more long-chain PTFE fibrils, calculated according to the Compositional Analysis Test Method, based on the total weight of the composition. In some embodiments, the composition 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, 5 wt% or less, or 1 wt% or less long-chain PTFE fibrils, calculated according to the Compositional Analysis Test Method, based on the total weight of the composition.

[0042] The multiple PTFE fibrils, or short-chain PTFE fibrils and long-chain PTFE fibrils, may comprise various forms of PTFE, such as C3-PTFE, C2-PTFE, C1-PTFE, or any combination thereof. C1-PTFE is a polytetrafluoroethylene polymer containing the repeating group -(CF2-C(F)(CF3))-. C2-PTFE is a polytetrafluoroethylene polymer containing the repeating group -(CF2-C(F)(CF2-CF3))-. C3-PTFE is a polytetrafluoroethylene polymer containing the repeating group -(CF2-C(F)(CF2-CF2-CF3))-. In some cases, it may be desirable to reduce the amount of fluorine in the final composition and / or reduce the amount of fluorine-carbon bonds used in making the PTFE. In some embodiments, the PTFE resin used to form the PTFE fibrils, and therefore the PTFE fibrils in the matrix, can include any combination of C1 short-chain PTFE, C2 short-chain PTFE, C3 short-chain PTFE, C1 long-chain PTFE, C2 long-chain PTFE, or C3 long-chain PTFE.

[0043] Multiple active particles The matrix of the present disclosure includes a plurality of active particles. The physical and / or chemical functionality of the particles comprising the plurality of active particles can vary based on the intended use of a given matrix or composition including such a matrix. The plurality of active particles can include catalysts, adsorbents (e.g., adsorbents, absorbents, or both), growth seeds, electroactive materials, metal-organic frameworks, bioactive substances, or any combination thereof.

[0044] In some embodiments, the plurality of active particles comprises a catalyst. A catalyst is a chemical species that alters the rate of one or more reactions without being consumed. The matrix may include any suitable catalyst, or any combination of catalysts, to promote any desired reaction. In some embodiments, the desired reaction is nitrobenzene reduction, nitrogen oxides (NO x) compound reduction, hydrogenation, or any combination thereof. Of particular interest are catalysts that can remove, prevent, and / or reduce the emission of harmful gases into the atmosphere. For example, a plurality of active particles can be used to remove one or more nitrogen oxides (NO x The catalyst may include a catalyst capable of reducing and / or converting diatomic nitrogen compounds (e.g., nitric oxide, nitrogen dioxide, dinitrogen trioxide, and / or nitrates) to diatomic nitrogen. The catalyst may be grafted onto a support, such as an adsorbent (described elsewhere herein).

[0045] In some embodiments, the catalyst can destroy ozone (O); i.e., the catalyst can convert ozone (O) to oxygen (O) through bond rearrangement. Examples of catalysts capable of ozone decomposition include silicates such as iron silicate, iron manganese silicate, zinc iron silicate, or any combination thereof; transition metal oxides such as zinc oxide, manganese oxide, copper oxide, cerium dioxide, or any combination thereof; metals such as reduced metals (i.e., zero-valent metals) including titanium, lead, iron, copper, zinc, chromium, cobalt, nickel, manganese, gold, silver, platinum, palladium, rhodium, tungsten, molybdenum, vanadium, zirconium, silicon, ruthenium, and combinations thereof; carbonates such as barium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, or any combination thereof; zeolites; and any combination thereof. Zeolites are aluminosilicate compounds composed of aluminum, oxygen, silicon, and one or more counterions.

[0046] In some embodiments, the catalyst can perform hydrogenation and / or cross-coupling reactions. Such chemical transformations can be useful in small molecule synthesis. Examples of catalysts capable of initiating such reactions include platinum, palladium, rhodium, iridium, PdCl2, iron, iron oxide, gold, silver, copper, copper oxide, compounds containing these, and any combination thereof.

[0047] In some embodiments, the plurality of active particles comprises an ozone-depleting catalyst comprising manganese oxide (e.g., amorphous manganese oxide), copper oxide, or both. Amorphous materials, in contrast to polymorphous materials, have little or no crystallinity. An example of an ozone-depleting catalyst comprising amorphous manganese oxide is available from Carus LLC (LaSalle, Illinois) under the trade name CARULITE 400. In some embodiments, the plurality of active particles comprises an ozone-depleting catalyst comprising cerium dioxide. In some embodiments, the plurality of active particles comprises an ozone-depleting catalyst comprising manganese oxide, copper oxide, cerium dioxide, or any combination thereof.

[0048] In some embodiments, the active particles include an adsorbent. In some embodiments, the adsorbent is an adsorbent, an absorbent, or both. Examples of absorbents include cellulose, fumed silica, cotton, natural or synthetic sponge, clay, sodium polyacrylate, sodium alginate, gelatin, and wool.

[0049] In some embodiments, the plurality of active particles comprises an adsorbent, such as a physisorbent, a chemisorbent, a physisorbent-chemisorbent hybrid, or any combination thereof. In some embodiments, the adsorbent is a chemisorbent-physisorbent hybrid. Chemisorbent-physisorbent hybrids include grafted hybrids and impregnated hybrids. Grafted hybrids are grafted chemisorbents onto physisorbents or grafted physisorbents onto chemisorbents. Impregnated hybrids are chemisorbents impregnated onto physisorbents or chemisorbents impregnated onto physisorbents. Grafted hybrids are characterized by the chemisorbent being covalently bonded to the physisorbent. Impregnated hybrids are characterized by the chemisorbent being present within the pores of the physisorbent. In impregnated hybrids, the chemisorbent is retained within the pores via non-covalent interactions (e.g., van der Waals forces). In some embodiments, the grafted or impregnated hybrid comprises one or more of the following: a physical adsorbent, activated carbon, a zeolite, a silicate, a metal-organic framework (MOF), or a mesoporous transition metal oxide.

[0050] An adsorbent is a material that can adsorb chemicals; i.e., the material can separate chemicals over at least a portion of its surface area. A physical adsorbent is an adsorbent that separates chemicals by forming weak interactions (e.g., van der Waals and / or electrostatic forces) between the physical adsorbent and the adsorbed chemical. A chemical adsorbent is an adsorbent that separates chemicals by forming ionic or covalent bonds between the chemical adsorbent and the adsorbed chemical.

[0051] The identity of the adsorbent will depend, at least in part, on the intended use of the composition. Adsorbents can include those capable of adsorbing basic compounds, acidic compounds, organic compounds, inorganic compounds, or any combination thereof. Such adsorbents can be physical adsorbents, chemical adsorbents, or physical adsorbent-chemical adsorbent hybrids. The acidic compounds, basic compounds, organic compounds, inorganic compounds, or any combination thereof can be in a liquid state, a gaseous state, and / or a vapor state (preferably), or any combination thereof.

[0052] In some embodiments, the sorbent is capable of adsorbing organic compounds in a liquid state, a gaseous state, and / or a vapor state (preferably), or both. An organic compound is a compound containing at least one carbon-hydrogen covalent bond. Examples of organic compounds that the sorbent can adsorb include aromatic hydrocarbons such as toluene, benzene, xylene, and ethylbenzene; siloxanes; and the 16 polycyclic aromatic hydrocarbons classified as priority pollutants by the U.S. Environmental Protection Agency in 2005 (i.e., naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, and the like. Examples of adsorbents that can adsorb organic compounds include polycyclic aromatic hydrocarbons such as fluoranthene, benzo(a)fluoranthene, dibenz(a,h)anthracene, benzo(ghi)perylene, and indeno(1,2,3-cd)pyrene; n-alkanes such as methane, ethane, and n-propane, n-butane, n-pentane, and n-hexane; n-alkenes such as methylene, ethylene, and propylene; various alcohols; aldehydes such as formaldehyde; siloxanes; and any combination thereof. Examples of adsorbents that can adsorb organic compounds include activated carbon, zeolites (e.g., zeolite X, zeolite A, zeolite Y, zeolite beta, and zeolite ZSM-5), silicates, metal-organic frameworks (MOFs), mesoporous transition metal oxides, and any combination thereof.

[0053] In some embodiments, the adsorbent can adsorb inorganic compounds in a liquid state, a gaseous state, and / or a vapor state (preferably), or both. Inorganic compounds are compounds that do not have at least one carbon-hydrogen bond. Examples of inorganic compounds that the adsorbent can adsorb include carbon dioxide; carbon monoxide; hydrogen sulfide; nitrogen oxides; sulfur oxides; water; perfluorocarbons such as tetrafluoromethane and hexafluoroethane; sulfur hexafluoride; ozone; and any combination thereof. Examples of adsorbents that can adsorb one or more inorganic compounds include activated carbon, zeolites (e.g., zeolite X, zeolite A, zeolite Y, zeolite beta, and zeolite ZsM-5), silicates, metal-organic frameworks (MOFs), mesoporous transition metal oxides, and any combination thereof. Zeolite physical adsorbents are one example of an adsorbent that can adsorb ozone.

[0054] In some embodiments, the sorbent is capable of adsorbing acidic compounds in a liquid state, a gaseous state, and / or a vapor state (preferably), or both. An acidic compound is a compound that, when mixed with water having a pH of 7, acidifies the water such that the pH of the resulting solution is less than 7. The acidic compound can be an inorganic compound or an organic compound. Examples of acidic compounds that the sorbent can adsorb include sulfur dioxide, nitrogen dioxide, hydrogen sulfide, sulfur trioxide, nitric oxide, and any combination thereof. Examples of adsorbents capable of adsorbing acidic compounds and / or acidic gases include chemical adsorbents including Group 1 metal (Li, Na, K, Rb, Cs, Fr) carbonates; metal oxides; Group 1 (Li, Na, K, Rb, Cs, Fr) metal hydroxides; Group 2 metal (Be, Mg, Ca, Sr, Ba, Ra) hydroxides; Group 2 metal (Be, Mg, Ca, Sr, Ba, Ra) oxides; N-containing compounds such as amines (e.g., tetraethylenepentamine, ethylenediamine, and 3-aminopropyltriethoxysilane), imines (e.g., polyethyleneimine), and ammonium salts (e.g., ammonium persulfate); or any combination thereof. In some embodiments, the selected chemical adsorbent may be grafted to or impregnated within a physical adsorbent such as activated carbon; zeolites; silicates; or any combination thereof.

[0055] In some embodiments, the adsorbent is capable of adsorbing basic compounds in a liquid state, a gaseous state, and / or a vapor state (preferably), or both. A basic compound is a compound that, when mixed with water having a pH of 7, basifies the water so that the pH of the resulting solution exceeds 7. The basic compound may be an inorganic or organic compound. Examples of basic compounds that the adsorbent can adsorb include ammonia and nitrogen trifluoride. Examples of adsorbents capable of adsorbing basic compounds include physical adsorbents such as activated carbon, zeolites, silicates, and combinations thereof. Further examples of adsorbents capable of adsorbing basic compounds include chemical adsorbents having carboxylic acid (COOH) functional groups. Examples of chemical adsorbents having carboxylic acid functional groups include citric acid, terephthalic acid, trimesic acid, tartaric acid, maleic acid, benzoic acid, oxalic acid, and combinations thereof. Chemical adsorbents capable of adsorbing basic compounds include inorganic acids such as boric acid, nitric acid, sulfuric acid, hydrochloric acid, hydrogen chloride, hydrogen fluoride, hydrogen bromide, phosphoric acid, perchloric acid, periodic acid, or any combination thereof. Such chemical adsorbents can be grafted onto or impregnated within physical adsorbents such as activated carbon, zeolites, silicates, or any combination thereof.

[0056] In some embodiments, the plurality of active particles comprises a metal-organic framework (MOF). As used herein, the term "metal-organic framework (MOF)" refers to a compound comprising clusters of metal ions coordinated to organic ligands that form a two-dimensional or three-dimensional structure. MOFs can be adsorbents (e.g., physisorbents, chemisorbents, or both), catalysts, or both. Examples of MOF adsorbents include copper benzene-1,3,5-tricarboxylate (C 18 H6Cu3O 12, also known as HKUST-1, Cu-BTC MOF or MOF-199; available from NOVOMOF GmbH, Sofingen, Aargau, Switzerland; zirconium 1,4-dicarboxybenzene MOF (Zr6O4(OH)4(dicarboxylate)6, also known as UiO-66; available from NOVOMOF GmbH, Switzerland); zirconium 4,4'-biphenyldicarboxylic acid MOF (Zr6O4(OH)4(4,4'-biphenyldicarboxylic acid)6, also known as UiO-67; available from NOVOMOF GmbH, Switzerland); and combinations thereof.

[0057] In some embodiments, the plurality of active particles comprises a bioactive material. A bioactive material is a material derived from a biological system. The bioactive material may function as an adsorbent and / or a catalyst. Examples of bioactive materials include proteins, nucleotides, nucleic acids, sugars and polysaccharides, lipids, and any combination thereof. In some embodiments, the bioactive material is a protein, such as an enzyme. Lactase is an example of an enzyme that may be used as a bioactive material.

[0058] In some embodiments, the plurality of active particles comprises growth seeds. The growth seeds can serve as nucleation points for the synthesis of metal-organic frameworks (MOFs). In some such embodiments, the growth seeds comprise copper nitrate as growth seeds for copper-based MOFs, such as copper benzene-1,3,5-tricarboxylate. In some embodiments, the growth seeds comprise trimesic acid as growth seeds for copper-based MOFs, such as copper benzene-1,3,5-tricarboxylate. The growth seeds may be reacted with one or more additional reagents before, during, or after forming a matrix from the MOF.

[0059] Each particle of the plurality of active particles has a particle size. Particle size is defined as the maximum distance between particles. The average particle size of the plurality of active particles can vary based on the intended use of the composition and / or the chemical or physical properties of the active particles. The plurality of active particles can have an average particle size of 0.001 μm or more, 0.01 μm or more, 0.1 μm or more, 1 μm or more, 5 μm or more, 10 μm or more, or 100 μm or more, as measured according to a dimensional analysis test method. The plurality of active particles can have an average particle size of 500 μm or less, 100 μm or less, 10 μm or less, or 1 μm or less, as measured according to a dimensional analysis test method.

[0060] Generally, for particles comprising a catalyst, smaller particle sizes may be preferred due to increased surface area and active site density available for catalytic reactions. Accordingly, in some embodiments where a plurality of active particles comprises a catalyst, the average particle size of the plurality of active particles is 0.001 μm to 5 μm, 0.001 μm to 1 μm, or 0.001 μm to 0.1 μm, as measured according to a Dimensional Analysis Test Method. Generally, active particles comprising a smaller particle size adsorbent may be preferred, as smaller particle sizes provide greater surface area and allow for greater diffusion. In some embodiments, where a plurality of active particles comprises an adsorbent, the average particle size of the particles in the plurality of active particles is 0.001 μm to 100 μm, 1 μm to 100 μm, or 0.001 μm to 0.1 μm, as measured according to a Dimensional Analysis Test Method.

[0061] The compositions and / or matrices of the present disclosure may have various amounts of active particles. The weight percent of the active particles (or any individual components of the active particles) in the composition and / or matrix may be calculated according to the compositional analysis test method.

[0062] The sum of the weight percents for each component of an active particle is considered to be the weight percent of the active particle including the components of the active particle. For example, if an active particle includes activated carbon, the amount of activated carbon is the weight percent of the active particle including activated carbon. If an active particle includes manganese oxide and copper oxide, the weight percent of the active particle including manganese oxide and copper oxide is the sum of the weight percent of manganese oxide and the weight percent of copper oxide.

[0063] The total amount of active particles is the sum of the weight percent of one or more components that make up the active particles in the composition and / or matrix. For example, in an embodiment in which the active particles include manganese oxide and copper oxide, the total active particle weight percent in the matrix is ​​the sum of the weight percent of manganese oxide and the weight percent of copper oxide.

[0064] In some embodiments, the total active particle weight percent in the composition and / or matrix is ​​50% by weight or more, 70% by weight or more, 80% by weight or more, or 90% by weight or more, based on the weight of the composition and / or matrix, according to a compositional analysis test method. In some embodiments, the total active particle weight percent in the composition and / or matrix is ​​95% by weight or less, 90% by weight or less, 80% by weight or less, or 70% by weight or less, based on the weight of the composition and / or matrix, according to a compositional analysis test method. Stated another way, in some embodiments, the composition and / or matrix contains 50% by weight or more, 70% by weight or more, 80% by weight or more, or 90% by weight or more active particles, based on the weight of the composition and / or matrix, according to a compositional analysis test method. In some embodiments, the composition and / or matrix contains 95% by weight or less, 90% by weight or less, 80% by weight or less, or 70% by weight or less active particles, based on the weight of the composition and / or matrix, according to a compositional analysis test method.

[0065] In some uses of the composition and / or matrix, a low amount of active particles in the composition and / or matrix can be beneficial. In some embodiments, the total active particle weight percent in the composition and / or matrix is ​​0 wt% or more, 0.001 wt% or more, 0.01 wt% or more, 0.1 wt% or more, 1 wt% or more, 2 wt% or more, 3 wt% or more, 4 wt% or more, 5 wt% or more, 10 wt% or more, or 15 wt% or more, based on the weight of the composition and / or matrix, according to a compositional analysis test method. In some embodiments, the total active particle weight percent in the composition and / or matrix is ​​20 wt% or less, 15 wt% or less, 10 wt% or less, 5 wt% or less, 4 wt% or less, 3 wt% or less, 2 wt% or less, 1 wt% or less, 0.1 wt% or less, 0.01 wt% or less, or 0.001 wt% or less, based on the weight of the composition and / or matrix, according to a compositional analysis test method. Stated another way, in some embodiments, the composition and / or matrix comprises at least 0%, at least 0.001%, at least 0.01%, at least 0.1%, at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, or at least 15% by weight of active particles, based on the weight of the composition and / or matrix, according to a Compositional Analysis Test Method. In some embodiments, the composition and / or matrix comprises no more than 20%, no more than 15%, no more than 10%, no more than 5%, no more than 4%, no more than 3%, no more than 2%, no more than 1%, no more than 0.1%, no more than 0.01%, or no more than 0.001% by weight of active particles, based on the weight of the composition and / or matrix, according to a Compositional Analysis Test Method.

[0066] matrix The compositions of the present disclosure include a matrix. The matrix includes a plurality of PTFE fibrils and a plurality of active particles. In some embodiments, the plurality of PTFE fibrils includes short-chain PTFE fibrils and long-chain PTFE fibrils. The plurality of PTFE fibrils can have any of the chemical and / or physical properties described herein. The plurality of active particles can have any of the chemical and / or physical properties described herein.

[0067] FIG. 1 shows a schematic diagram of a matrix consistent with embodiments of the present disclosure. Matrix 10 includes long-chain PTFE fibrils 20, short-chain PTFE fibrils 30, and a plurality of active particles 40. As described elsewhere herein, the long-chain PTFE fibrils 30 are longer and wider than the short-chain PTFE fibrils 30. The long-chain PTFE fibrils can be observed when a composition of the present disclosure is imaged at relatively low magnification (e.g., ×370; see FIG. 10). For example, some of the long-chain PTFE fibrils can be seen in the SEM image of a matrix consistent with the present disclosure in FIG. 10 (Box 21). The constituent fibrils that make up the long-chain PTFE fibrils are visible (Box 21). Disordered short-chain PTFE fibrils, distinct from the long-chain PTFE fibrils, can also be seen in the same figure (Boxes 31a, 31b, and 31c). As described elsewhere herein, one or more short-chain PTFE fibrils may be located within a long-chain PTFE fibril 32, but the short-chain PTFE fibrils and long-chain PTFE fibrils are separate entities. Thus, the short-chain PTFE fibrils located within a long-chain PTFE fibril are distinct from the multiple constituent fibrils 22 (FIG. 2B) that make up the long-chain PTFE fibril. As described elsewhere herein, the constituent fibrils of a long-chain PTFE fibril are longer than the short-chain PTFE fibrils.

[0068] As shown in box 50 in FIG. 1, when imaged at relatively high magnifications (e.g., ×9,000; ×7,000; ×11,000; ×20,000), the multiple small-chain PTFE fibrils have a largely disordered configuration; i.e., the fibrils extend in different directions (e.g., x, y, and z directions). This phenomenon is clearly visible in the SEM image of a matrix consistent with the present disclosure in FIG. 9. A composition containing only short-chain PTFE fibrils does not contain two distinct populations of PTFE fibrils (i.e., short-chain PTFE fibrils and long-chain PTFE fibrils). As discussed above, a composition having a single population of PTFE fibrils (e.g., short-chain PTFE fibrils) can be distinguished from a composition having two populations of PTFE fibrils (e.g., short-chain PTFE fibrils and long-chain PTFE fibrils) using microscopy (e.g., scanning electron microscopy).

[0069] A plurality of active particles are distributed throughout the matrix and contact and / or interact with long-chain PTFE fibrils 20 (if present), short-chain PTFE fibrils 30, or both (FIG. 1). Active particles that interact with other active particles, long-chain PTFE fibrils 20 (if present), short-chain PTFE fibrils 30, or combinations thereof, are physically and / or chemically immobilized within the matrix. That is, the term "interaction" refers to physical forces (e.g., frictional forces, gravity, compression forces, tension forces, electrical forces, magnetic forces, spring forces, applied forces, and normal forces) or chemical forces (e.g., van der Waals forces, Debye forces, Keesom forces, London dispersion forces, dipole-dipole forces, and hydrogen bonding) between two or more active particles, between an active particle and a short-chain PTFE fibril (or multiple short-chain PTFE fibrils), between an active particle and a long-chain PTFE fibril (if present; or multiple long-chain PTFE fibrils), or combinations thereof.

[0070] The plurality of active particles may have one or more configurations that interact with short-chain PTFE fibrils, long-chain PTFE fibrils (if present), or both. In some embodiments, at least a portion of the plurality of active particles and at least a portion of the plurality of PTFE fibrils adopt a catenate structure, an aggregated structure, or both. In some embodiments, at least a portion of the plurality of active particles form a catenate structure around one or more short-chain PTFE fibrils, one or more long-chain PTFE fibrils (if present), or both; at least a portion of the plurality of active particles form an aggregated structure with one or more short-chain PTFE fibrils, one or more long-chain PTFE fibrils (if present), or any combination thereof.

[0071] The terms "catenate structure" and "catenation structure" are used interchangeably to refer to a self-supporting network of active particles that encapsulate at least a portion of one or more PTFE fibrils. FIG. 3A is a schematic diagram of a catenate structure 80. In a catenate structure, multiple active particles 40 form a self-supporting network that encapsulates at least a portion of one or more PTFE fibrils (e.g., one or more long-chain PTFE fibrils, one or more short-chain PTFE fibrils, or both). While the self-supporting network may contact and / or interact with one or more PTFE fibrils that at least partially encapsulate it, the primary interaction that holds the catenate structure together is the physical interaction between adjacent particles. While not wishing to be bound by theory, it is believed that if at least a partially encapsulated (or fully encapsulated) PTFE fibril can be removed, the self-supporting network of particles remains undisturbed. The individual active particles involved in a catenate structure may not be well defined, as the active particles may fuse together to form a self-supporting network.

[0072] The self-supporting network of active particles can encapsulate a portion of a single PTFE fibril, a portion of multiple PTFE fibrils, an entire PTFE fibril, or an entire plurality of PTFE fibrils in a catenate structure. The self-supporting network of active particles can encapsulate at least a portion of one or more short-chain PTFE fibrils, at least a portion of one or more long-chain PTFE fibrils, or both in a catenate structure. It is generally believed that the catenate structure primarily comprises the encapsulation of at least a portion of one or more short-chain PTFE fibrils.

[0073] 11 and 12 are SEM images of compositions consistent with embodiments of the present disclosure that clearly show the catenate structure highlighted in boxes 71, 72, and 73. In these images, the particles form a self-supporting network, or "bead-like" structure, surrounding one or more PTFE fibrils (e.g., the one or more PTFE fibrils are threads, and the particle's self-supporting network is a bead). The extent of the catenate structure in box 71 is such that one or more PTFE fibrils are not visible (e.g., one or more PTFE fibrils are completely encapsulated by the catenate structure). In contrast, in the catenate structure shown in boxes 72 and 73, a portion of one or more PTFE fibrils involved in the catenate structure are encapsulated within the self-supporting network of the active particle. For example, the catenate structure may have interstices through which individual PTFE fibrils can be observed (see boxes 72 and 73 in FIG. 12). * (denoted by ).

[0074] Without wishing to be bound by theory, it is believed that the catenate structure may reduce the likelihood of particles shedding from the composition (e.g., before, during, and / or after disposition on the porous substrate). Furthermore, it is believed that particles employing catenate structures may have a large exposed surface area due to their spacing and number of exposed faces. This property may increase their activity as catalysts, adsorbents, growth seeds, MOFs, or any combination thereof.

[0075] As used herein, the terms "agglomerated structure" and "agglomerated structure" are used interchangeably and refer to active particles or agglomerates of active particles that are at least partially held together by one or more PTFE fibrils (e.g., short-chain PTFE fibrils or long-chain PTFE fibrils). In contrast to catenate structures, particles in agglomerate structures generally do not form a self-supporting network independent of the PTFE fibrils. In agglomerate structures, active particles or agglomerates of active particles are held in place by interactions with one or more PTFE fibrils (e.g., short-chain PTFE fibrils) that extend through (e.g., penetrate) the particles or agglomerates. Active particle agglomerates are clusters of two or more active particles, with each active particle interacting with at least one other active particle in the cluster. In agglomerate structures containing agglomerates, the agglomerates are held together by both interactions between the active particles and interactions between the active particles and the PTFE fibrils. In contrast to catenate structures, active particles in agglomerate structures are generally well-defined.

[0076] 3B is a schematic diagram of two agglomerate structures 70 and 71 consistent with embodiments of the present disclosure. Agglomerate structure 70 is one in which PTFE fibrils from a plurality of PTFE fibrils 20 / 30 (either short-chain PTFE fibrils or long-chain PTFE fibrils) thread through (i.e., interact with) a single active particle from a plurality of active particles 40. Agglomerate structure 71 is one in which some PTFE fibrils from a plurality of PTFE fibrils 20 / 30 thread through (i.e., interact with) an agglomerate comprising a plurality of active particles 40.

[0077] 9 is an SEM image of a composition consistent with embodiments of the present disclosure, showing various agglomeration structures highlighted by boxes 81, 82, 83, and 84. Boxes 81, 82, and 83 show agglomeration structures in which multiple short-chain PTFE fibrils thread through agglomerates of active particles. Box 84 shows agglomeration structures in which multiple short-chain PTFE fibrils thread through a single active particle.

[0078] Without wishing to be bound by theory, it is believed that the agglomerated structure may impart some mechanical stability to at least a portion of the plurality of active particles, at least a portion of the plurality of PTFE fibrils (e.g., long-chain PTFE fibrils, short-chain PTFE fibrils, or both). For example, it is believed that the agglomerated structure may at least partially inhibit one or more of the PTFE fibrils involved in the agglomerated structure from shrinking (i.e., decreasing in length). Furthermore, it is believed that the agglomerated structure reduces the likelihood of particles falling off due to the strength imparted by the PTFE fibrils with which the particles of the agglomerated structure interact.

[0079] Free active particles and free PFTE fibrils The composition of the present disclosure comprises a matrix as described herein. In some embodiments, the composition may comprise one or more additional components. Examples of additional components include free active particles and free PTFE fibrils. In the porous substrate onto which the composition is disposed, the individual components of the composition may or may not be located in different locations of the porous substrate (e.g., on a major surface, impregnated within the substrate, or embedded within the substrate) as described elsewhere herein.

[0080] In some embodiments, the composition includes free active particles. Free active particles differ from multiple active particles in a matrix in that the free active particles do not interact with multiple PTFE fibrils (or free PTFE fibrils as discussed elsewhere herein). Free active particles are embedded or impregnated within a porous substrate. Thus, the term "free active particles" refers to active particles that are embedded or impregnated within a porous substrate and do not interact with one or more PTFE fibrils. Free active particles can have any chemical and / or physical identity as disclosed herein. In some embodiments, the multiple active particles and the free active particles are made from the same material (e.g., have the same chemical and / or physical identity). For example, in some embodiments, the multiple active particles include a catalyst and the free active particles include the same catalyst. In some embodiments, the multiple active particles and the free active particles are made from different materials (e.g., have different chemical and / or physical identities). For example, in some embodiments, the multiple active particles may include a catalyst and the free active particles may include an adsorbent. In some embodiments, the plurality of active particles may include a first adsorbent and the loose active particles may include a second adsorbent that is different from the first adsorbent.

[0081] In some embodiments, the composition includes free PTFE fibrils. Free PTFE fibrils differ from multiple PTFE fibrils in a matrix in that the free PTFE fibrils are not part of the fibril-active particle matrix structure. Free PTFE fibrils do not interact with the matrix or the free active particles, although two or more free PTFE fibrils may interact. Free PTFE fibrils are embedded or impregnated within a porous substrate. Thus, the term "free PTFE fibrils" refers to PTFE fibrils that are embedded or impregnated within a porous substrate and do not interact with the matrix or the free active particles. Free PTFE fibrils may interact with each other. Free PTFE fibrils may be short-chain PTFE fibrils, long-chain PTFE fibrils, or both.

[0082] Free active particles and free PTFE fibrils can be visualized using microscopy, such as scanning electron microscopy. Figure 18D shows an example image of free PTFE fibrils. Figure 18D is an image of a porous substrate having a composition consistent with embodiments of the present disclosure disposed thereon. Free PTFE fibrils can be seen running across the surface. These fibrils do not interact with the matrix or free active particles. Figure 14B shows an example of free active particles embedded and / or impregnated within a porous substrate. Figure 14B is a cross-sectional view of a porous substrate having a composition consistent with embodiments of the present disclosure disposed thereon. Small particles (active particles) can be seen parallel to the substrate polymer particles. The particles do not interact with the matrix or free PTFE fibrils.

[0083] Porous substrate having a composition disposed thereon The present disclosure provides porous substrates on which compositions and / or components of the present disclosure are disposed. Such substrates can be further processed into various materials, such as filter media, membranes, reticulated foams, or reaction surfaces, for the preparation of secondary materials. The materials can also be included in filters; used as catalytic media for various chemical syntheses in petrochemical or pharmaceutical applications; used as intake filters in engine air systems; or act as destruction catalysts for chemical protection of membrane materials.

[0084] The porous substrate having the composition disposed thereon can have the composition disposed on at least a portion of a major surface; the composition impregnated within the substrate; the composition embedded within the substrate; or any combination thereof.

[0085] porous substrate The substrate of the present disclosure is a porous substrate. A porous substrate is defined by one or more major surfaces. A major surface is a surface of a substrate that forms an interface with the surrounding environment. Pores can be connected to a major surface of a substrate. Pores connected to a major surface are pores that allow access to a fluid (i.e., liquid or gas) or solid through the exterior surface. Pores connected to a major surface are not considered part of a major surface because the pore volume extends into the interior of the substrate. For example, the major surfaces of a cubic porous substrate are facets of the cube. The major surfaces can have a constant or varying topography in the x, y, and / or z directions. For example, each of the major surfaces of a porous substrate can be smooth or rough. A porous substrate can have a single continuous major surface, such as a spherical or ovoid substrate. A porous substrate can have multiple major surfaces, such as a polyhedron.

[0086] A porous substrate has a plurality of pores. A pore is defined as an empty space within the substrate. The empty space of a pore is defined by the pore surface. The total amount of empty space is the pore volume. Pores can be through pores, open pores, or blind pores. Through pores are pores that are connected to (e.g., accessible from) a major surface by two or more pore openings. Open pores are pores that are connected to (e.g., accessible from) a single pore opening on one major surface. Blind pores are pores that are not connected to a pore opening on a major surface. Pores can have a variety of morphologies.

[0087] The porous substrate comprises a plurality of macropores. Macropores are pores that exist between portions of the material that constitute the porous substrate (e.g., between polymer networks). Generally, macropores have a pore opening size of 1 mm or more, some of which are visible to the naked eye. The composition may impregnate some of the macropores of the porous substrate (as discussed elsewhere herein). The macropores may be through pores, blind pores, or open pores.

[0088] The porous substrate may include a plurality of micropores. Micropores are pores that exist between solid portions of the material that constitutes the porous substrate. Micropores have a pore opening size of less than 1 mm. In some cases, micropores may exist within the pore walls of macropores. The composition may impregnate a portion of the micropores of the porous substrate (as discussed elsewhere herein). The micropores may be through pores, blind pores, or open pores. The micropores may or may not be collapsing pores as defined herein.

[0089] The term macro / micro is understood to mean macropores and / or micropores, if present. It is understood that the micropores associated with the term macro / micro are not collapsible pores.

[0090] In some embodiments, a porous substrate made of a wettable polymer material may include a plurality of collapsible pores. The collapsible pores are the interstitial spaces between polymer chains within the solid portion of the substrate into which a composition (as discussed elsewhere herein) may be embedded. The collapsible pores are collapsed within the substrate framework and are inaccessible to fluids or solids prior to wetting with the wettable material. Wetting of the wettable material may cause the collapsible pores to expand, making such pores accessible to fluids or solids. Drying of the wettable material may cause the collapsible pores to collapse, thereby trapping some or all of the material within the pores in the interstitial spaces between the polymer chains upon collapse.

[0091] The porous substrate may be made of any suitable material. Some porous substrates are made of wettable materials. A wettable substrate is a substrate made of a material that can absorb a certain amount of liquid to expose collapsible pores. The wettable porous substrate may be a foam. The wettable porous substrate may be a reticulated foam. The term reticulated foam is typically used to refer to open-cell foams that form a network or mesh (as opposed to closed-cell foams that form a cellular or cellular structure). The majority of the pores in reticulated foams may be open and / or through-pores. Reticulated foams are typically highly porous and have low density. For example, reticulated foams may have a porosity of 60% or more, 90% or more, or 95% or more. Reticulated foams may be polymer-based; metal-, metal oxide-, or metal carbide-based; carbon-based; ceramic-based; or any combination thereof. The reticulated foam may be made of only one material or two or more materials. Examples of polymer-based reticulated foams include reticulated polyester, reticulated polyether, reticulated polyurethane, non-heat-treated reticulated polyurethane, reticulated cellulose, and reticulated melamine. Examples of carbon-based reticulated foams include reticulated activated carbon, reticulated vitreous carbon, and reticulated graphene. Examples of metal-based reticulated foams include reduced metals (i.e., zero-valent metals) such as titanium, lead, iron, copper, zinc, chromium, cobalt, nickel, manganese, gold, silver, platinum, palladium, rhodium, tungsten, molybdenum, vanadium, zirconium, silicon, ruthenium, or any combination thereof; reticulated alloys such as reticulated steel; or reticulated foams made from any combination thereof. Examples of metal oxide-based reticulated foams include reticulated silicon oxide. Examples of metal carbide-based reticulated foams include reticulated silicon carbide.

[0092] The reticulated foam can have any suitable pores per inch (PPI). For example, the reticulated foam can be 3 PPI or more, 10 PPI or more, 20 PPI or more, 30 PPI or more, 40 PPI or more, 50 PPI or more, 60 PPI or more, 70 PPI or more, 80 PPI or more, 90 PPI or more, or 100 PPI or less, 90 PPI or less, 80 PPI or less, 70 PPI or less, 60 PPI or less, 50 PPI or less, 40 PPI or less, 30 PPI or less, 20 PPI or less, or 10 PPI or less.

[0093] Impregnated porous substrate In some embodiments, the porous substrate onto which the composition is disposed is impregnated with the composition. In some such embodiments, at least a portion of the macro / micropores of the porous substrate are impregnated with the composition of the present disclosure. The macro / micropores may be impregnated with the composition or one or more components of the composition (e.g., the matrix, free active particles (if present), free PTFE particles (if present), or any combination thereof).

[0094] The term "impregnated," as used in the context of a porous substrate, refers to a porous substrate that includes macro / micropores having macro / micropore surfaces at least partially coated with the composition; macro / micropores having macro / micropore regions partially or completely filled with the composition; or both. For example, in some embodiments, a substrate can include a portion of macro / micropores having macro / micropore surfaces partially or completely coated with the composition. In some embodiments, a substrate can include a portion of macro / micropores having a macro / micropore volume partially or completely filled with the composition. In some embodiments, a substrate can include a portion of macro / micropores having a macropore volume partially or completely filled with at least one particle of free active particles.

[0095] In some embodiments where the composition comprises free active particles, the substrate may comprise a first portion of macro / micropores impregnated with the composition and a second portion of macro / micropores impregnated with at least one particle of the free active particles. In some embodiments where the composition comprises free active particles, the substrate may comprise a first portion of macro / micropores impregnated with the composition; a second portion of macro / micropores impregnated with at least one particle of the free active particles; and a third portion of macro / micropores impregnated with the composition and at least one particle of the free active particles.

[0096] Embedded porous substrate In some embodiments, the composition is embedded in a solid portion of a porous substrate. The composition and / or one or more components of the composition (e.g., the matrix, free active particles if present, free PTFE particles if present, or any combination thereof) may be embedded within the porous substrate.

[0097] The terms "embedded" and "embedded," with respect to a porous substrate, refer to a composition that is intercalated (e.g., inserted) into collapsing pores of a substrate and remains in the solid portion of the substrate at or near the location of the collapsing pores after the collapsing pores have at least partially collapsed. Collapsing pores are formed when a wettable substrate absorbs a wetting fluid and expands, exposing interstitial spaces into which the composition can intercalate. Upon removal of a sufficient amount of the wetting fluid, the substrate shrinks, and upon shrinkage, any components of the composition that were intercalated into the collapsing pores become embedded within the solid portion of the substrate.

[0098] Without wishing to be bound by theory, it is believed that embedding the composition or components of the composition within the substrate can impart some mechanical strength to the substrate. For example, embedded free PTFE fibrils (long and / or short chains) are believed to increase the mechanical strength of the substrate, thereby increasing its stability against microcracking.

[0099] FIG. 5 shows a schematic diagram of the embedding of a composition into a porous substrate by the formation of collapsing pores and intercalation of such pores. FIG. 5 shows a cross-sectional view of a solid portion of a wettable porous substrate 600A comprised of a plurality of polymer chains 610. Background 602 is included for clarity. Before the wetting fluid is added, the collapsing pores are in a collapsed state. When the wetting fluid is added, the substrate absorbs a portion of the wetting fluid and expands, forming an expanded substrate 600B with newly exposed collapsing pores 650. In the presence of a composition, the composition and / or individual components 660 of the composition (e.g., matrix, free active particles, dissolved components of free active particles that can precipitate to form free active particles, free PTFE fibrils, or any combination thereof) can migrate into the newly exposed collapsing pores 650 to form an intercalated substrate 600C. Removal of at least a portion of the wetting liquid collapses the collapsing pores as the polymer chains retract, thereby embedding the intercalated components within the solid portion of the substrate to form embedded substrate 600D. In embodiments in which the dissolved components constitute at least a portion of the free active particles, removal of at least a portion of the wetting liquid can result in supersaturation and precipitation of the dissolved components, producing free active particles embedded within the substrate. Without wishing to be bound by theory, it is believed that embedded free active particles are less likely to be sterically blocked than multiple active particles that are part of the matrix. Thus, embedded free active particles may be more likely to function as catalysts and / or adsorbents.

[0100] Figure 17D shows a scanning electron micrograph of a cross section of the embedded substrate, showing embedded PTFE fibrils running along the surface of the cross section.

[0101] A porous substrate having a composition disposed on at least a portion of a major surface thereof, the composition being embedded within the substrate, impregnated into at least a portion of the macro / micropores, or any combination thereof. Porous substrates are disclosed having a first portion of a composition disposed on at least a portion of a major surface thereof and a second portion of the composition impregnated therein. In some such embodiments, at least a portion of a plurality of macro / micropores of the substrate are disclosed that are impregnated with the composition. In some embodiments, the porous substrate has a first portion of the plurality of macro / micropores impregnated with the composition and a second portion of the plurality of macro / micropores impregnated with components of the composition. In some such embodiments where the composition includes free active particles, the porous substrate has a first portion of the macro / micropores impregnated with the matrix or the entire composition and a second portion of the macro / micropores impregnated with at least one of the free active particles.

[0102] FIG. 4 is a schematic diagram illustrating a porous substrate having at least a portion of its major surfaces coated with a first portion of the composition of the present disclosure; a first portion of its macro / micropores impregnated with a second portion of the composition; and a second portion of its macro / micropores impregnated with at least one free active particle. The porous substrate 100 includes six major surfaces, although only three major surfaces (110, 111, and 112) are shown. At least a portion of each major surface is coated with the first portion of the composition 10. The porous substrate includes a plurality of macro / micropores 120 having at least one macro / micropore opening connected to the major surfaces, the macro / micropores having different pore opening diameters and morphologies. At least a portion of the plurality of macro / micropores 120 is impregnated with the second portion of the composition 10, at least one free active particle 130, or both. For example, a first portion 122 of the plurality of macro / micropores 120 is impregnated with the second portion of the composition 10. In some embodiments, at least a portion of the interior surface of one or more macro / micropores in the first portion 122 of the plurality of macro / micropores 120 may be coated with the second portion of Composition 10. In some embodiments, at least a portion of the macro / micropore volume of one or more of the pores in the first portion 122 of the plurality of pores 120 may be filled with the second portion of Composition 10. In some embodiments, the entire macropore volume of one or more pores in the first portion 122 of the plurality of macro / micropores may be filled with the second portion of Composition 10. The second portion 124 of the plurality of macro / micropores 120 may be impregnated with one or more particles of the free active particles 130. The third portion 126 of the plurality of macro / micropores 120 may be impregnated with both Composition 10 (the third portion) and at least one particle of the free active particles 130.

[0103] Disclosed is a porous substrate having a first portion of a composition of the present disclosure disposed on at least a portion of one or more major surfaces and a second portion of the composition embedded within the substrate. In some such embodiments, multiple components of the composition may be embedded within the substrate. For example, in some embodiments, one or more free PTFE fibrils, one or more free active particles, a matrix, or any combination thereof may be embedded within the substrate. In some embodiments, the porous substrate of the present disclosure has a composition disposed on at least a portion of one or more major surfaces and at least one free PTFE fibril (e.g., a short-chain PTFE fibril) embedded within the substrate.

[0104] Porous substrates are disclosed having a first portion of the disclosed composition disposed on at least a portion of one or more major surfaces, impregnated with a second portion of the composition, and having a third portion of the composition embedded therein. In some such embodiments, at least a portion of the macro / micropores of the substrate are impregnated with the second portion of the composition. In some embodiments, the porous substrate has a first portion of the macro / micropores impregnated with a first component of the composition (e.g., a matrix) and a second portion of the macro / micropores impregnated with a second component of the composition (e.g., free active particles). In some such embodiments, multiple components of the third portion of the composition may be embedded within the substrate. In some embodiments, at least one free PTFE fibril (e.g., a small-chain PTFE fibril) is embedded within the substrate. In some embodiments, at least one free active particle is embedded within the substrate.

[0105] In some embodiments, a greater amount of the composition is impregnated or embedded within the porous substrate than is disposed on at least a portion of the substrate's major surface. In some such embodiments, the amount of composition disposed on at least a portion of the major surface results in a thin layer of the composition on the major surface. Without wishing to be bound by theory, it is believed that embedding the matrix and / or free active particles within the solid portion of the substrate skeleton can be advantageous from an adsorption perspective. For example, in embodiments in which a thin film of the composition is disposed on at least a portion of the major surface, the pressure drop across the porous substrate can be less than the pressure drop across a porous substrate in which a thicker film of the composition is disposed on the major surface. Furthermore, a substrate in which a thin film of the composition is disposed on the major surface can have molecular diffusion rates that are less affected by the film thickness and porosity than a porous substrate in which a thick film of the composition is disposed on the major surface.

[0106] The weight percentage of each component of the porous substrate having the composition disposed thereon can be determined according to the Compositional Analysis Test Method.

[0107] In some embodiments, the porous substrate having the composition disposed thereon comprises at least 0.001 wt%, at least 0.01 wt%, at least 0.1 wt%, at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, or at least 95 wt% of the porous substrate, based on the total weight of the substrate-composition (the total weight of the substrate and the composition disposed thereon), calculated according to the Compositional Analysis Test Method. In some embodiments, the porous substrate having the composition disposed thereon comprises at most 99 wt%, at most 95 wt%, at most 90 wt%, at most 80 wt%, at most 70 wt%, at most 60 wt%, at most 50 wt%, at most 40 wt%, at most 30 wt%, at most 20 wt%, at most 10 wt%, at most 5 wt%, at most 1 wt%, or at most 0.01 wt% of the porous substrate, based on the total weight of the substrate-composition, calculated according to the Compositional Analysis Test Method.

[0108] In some embodiments, the porous substrate having the composition disposed thereon comprises at least 0.001 wt%, at least 0.01 wt%, at least 0.1 wt%, at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, or at least 95 wt% of the composition, calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition. In some embodiments, the porous substrate having the composition disposed thereon comprises at most 99 wt%, at most 95 wt%, at most 90 wt%, at most 80 wt%, at most 70 wt%, at most 60 wt%, at most 50 wt%, at most 40 wt%, at most 30 wt%, at most 20 wt%, at most 10 wt%, at most 5 wt%, at most 1 wt%, or at most 0.01 wt% of the composition, calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition.

[0109] In some embodiments, the porous substrate having the composition disposed thereon comprises at least 0 wt%, at least 1 wt%, at least 2 wt%, at least 3 wt%, at least 4 wt%, at least 5 wt%, at least 10 wt%, or at least 15 wt%, at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 70 wt%, at least 80 wt%, or at least 90 wt% active particles, calculated according to Compositional Analysis Test Methods, based on the total weight of the substrate-composition. In some embodiments, the porous substrate having the composition disposed thereon comprises at most 95 wt%, at most 90 wt%, at most 80 wt%, at most 70 wt%, at most 50 wt%, at most 40 wt%, at most 30 wt%, at most 20 wt%, at most 15 wt%, at most 10 wt%, at most 5 wt%, at most 4 wt%, at most 3 wt%, at most 2 wt%, or at most 1 wt% active particles, calculated according to Compositional Analysis Test Methods, based on the total weight of the substrate-composition.

[0110] In some embodiments, the porous substrate having the composition disposed thereon comprises 1% or more, 5% or more, 15% or more, 25% or more, 45% or more, 55% or more, 65% or more, or 80% or more by weight of PTFE fibrils (short-chain PTFE fibrils plus long-chain PTFE fibrils), calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition. In some embodiments, the composition comprises 95% or less, 80% or less, 65% or less, 55% or less, 45% or less, 25% or less, 15% or less, or 5% or less by weight of PTFE fibrils, calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition.

[0111] method To produce the porous substrate of the present disclosure, a method is disclosed in which the composition of the present disclosure is disposed on a porous substrate.

[0112] 6, 7, and 8 are flow diagrams illustrating aspects of exemplary methods disclosed herein. The steps can be performed in any order. In some embodiments, multiple steps can be performed simultaneously. Steps indicated by dashed boxes are optional. Each optional step can be performed in a manner that includes none, one, or more additional optional steps (if multiple optional steps are included). For example, the first optional step can be performed with one or more additional optional steps; or it can be performed with no additional optional steps. The flow diagrams also include boxes directed to components that make up various compositions in the method (e.g., concentrated matrix premix, matrix premix, emulsion, aerated emulsion, aerated matrix premix, hydrated composition, etc.). Such boxes have element numbers designated with a "c." It is understood that components included in a step can also be included in any downstream steps, with the exception of drying steps. For example, a dispersant included in a first step may then be included in a second step, a third step, etc., until the drying step is complete, in which case the dispersant may be at least partially removed during the drying step.

[0113] 6 is a flow chart outlining a first exemplary method for disposing a composition of the present disclosure on a porous substrate to obtain a porous substrate of the present disclosure. The composition includes a matrix. The matrix includes a plurality of active particles and a plurality of PTFE fibrils formed from a PTFE resin. In some embodiments, the composition further includes free active particles, free PTFE fibrils, or both.

[0114] Method 200 optionally includes, in optional step 210, aerating the emulsion to form an aerated emulsion. An aerated emulsion or mixture is characterized by the presence of air bubbles and / or air pockets. For example, an aerated emulsion may be characterized by having air bubbles on the surface. Aeration may be achieved using a variety of techniques, such as mechanical agitation, gas injection, bottom-up bubbling, or a combination thereof.

[0115] The emulsion (210c) comprises a PTFE resin, a dispersing agent, and a surfactant. The surfactant may be any surfactant described elsewhere herein. The dispersing agent may be any dispersing agent described elsewhere herein. The aerated emulsion (201c) comprises a PTFE resin, a dispersing agent, and a surfactant.

[0116] In some embodiments, method 200 optionally includes forming an emulsion by diluting the concentrated mixture to form an emulsion (not shown in FIG. 6). The concentrated mixture may include an emulsion of PTFE resin and a dispersant. In some embodiments, the concentrated mixture includes at least a portion of a surfactant. In some embodiments, the concentrated mixture includes 60 wt. % PTFE resin (e.g., 60 wt. % short-chain PTFE resin) based on the total weight of the concentrated mixture. In some embodiments, the concentrated mixture is diluted with a dispersant. In some embodiments, the concentrated mixture is diluted with a solution including a dispersant and a surfactant. The surfactant may be the same surfactant as in the emulsion or a different surfactant.

[0117] Method 200 optionally includes aerating the matrix premix to form an aerated matrix premix in optional step 230. Aeration can be achieved by any means described elsewhere herein. The aerated matrix premix (230c) includes a PTFE resin, a dispersant, a surfactant, and a solid particulate composition.

[0118] The first exemplary method 200 optionally includes, in optional step 220, adding a solid particulate composition to the aerated emulsion to form a matrix premix. The matrix premix (220c) includes a PTFE resin, a surfactant, a solid particulate composition, and a dispersant. The solid particulate composition includes solid particulates. In some embodiments, the solid particulate composition includes 100% by weight of solid particulates (i.e., the solid particulate composition does not include any other components). In other embodiments, the solid particulate composition includes solid particulates and a liquid carrier. The liquid carrier can include water, one or more organic solvents (e.g., ethyl acetate, ethanol, methanol, isopropanol, butanol, dichloromethane, toluene, acetonitrile, acetone, diethyl ether, amyl alcohol, or tetrahydrofuran); or both. In some such embodiments, the solid particulates in the solid particulate composition are dissolved in the liquid carrier. In other embodiments, the solid particulates of the solid particulate composition are suspended in the liquid carrier. In yet other embodiments, a first portion of the solid particulates is dissolved in the liquid carrier and a second portion of the solid particulates is suspended in the liquid carrier.

[0119] The plurality of active particles comprises at least a portion of the solid particulates. In embodiments in which the composition comprises free active particles, the free active particles comprise at least a portion of the solid particulates. In some embodiments, the solid particulates may already be in the form of a plurality of active particles and / or free active particles (if present). In some embodiments, the solid particulates are not in the form of a plurality of active particles and / or free active particles (if present). In some such embodiments, at least a portion of the solid particulates become the plurality of active particles and / or free active particles (if present) through aggregation and / or precipitation of the solid particulates. For example, in some embodiments, at least a portion of the solid particulates are dissolved in the liquid carrier, and throughout the process (e.g., during the drying step), the dissolved solid particulates become supersaturated and precipitate to form the plurality of active particles and / or free active particles (if present).

[0120] The amount of solid particulate (included in the solid particulate composition) can vary depending on the identity of the solid particulate and the desired end use of the porous substrate. In some embodiments, the aerated matrix premix comprises 0.5 wt.% or more, 10 wt.% or more, 30 wt.% or more, or 50 wt.% or more of the solid particulate, based on the total weight of the aerated matrix premix. In some embodiments, the aerated matrix premix comprises 90 wt.% or less, 50 wt.% or less, 30 wt.% or less, or 10 wt.% or less of the solid particulate, based on the total weight of the aerated matrix premix.

[0121] Method 200 includes, in step 260, contacting at least a portion of a porous substrate with a matrix premix or an aerated matrix premix. The porous substrate includes at least one major surface and a plurality of macro / micropores (260c) connecting the major surface. In some embodiments, the porous substrate is a wettable porous substrate. The substrate is contacted with the matrix premix or the aerated matrix premix so as to expose at least a portion of the major surface and at least a portion of the plurality of macro / micropores of the porous substrate to the matrix premix or the aerated matrix premix. The contacting may be in the form of immersing at least a portion of the porous substrate in the matrix premix or the aerated matrix premix; pumping the matrix premix or the aerated matrix premix around at least a portion of the porous substrate; spraying an aerosolized matrix premix of the aerated matrix premix onto at least a portion of the porous substrate; or a combination thereof.

[0122] Method 200 further includes disposing the hydrated composition on a porous substrate. The hydrated composition includes the matrix, any other composition components (if present), at least a portion of the dispersant, at least a portion of the liquid carrier (if present), at least a portion of the wetting liquid (if present), and at least a portion of the surfactant. The plurality of active particles in the matrix comprises at least a portion of solid particulates. In some embodiments, the hydrated composition may include free active particles, free PTFE fibrils, or both. The hydrated composition may be disposed on at least a portion of at least one major surface of the substrate, may be impregnated into at least a portion of a plurality of macro / micropores connecting to at least one major surface, may be intercalated within collapsible pores of the substrate, or any combination thereof. In some embodiments, the porous substrate is a wettable porous substrate, the collapsible pores may be exposed by contacting the wettable porous substrate with a wetting liquid before contacting the wettable porous substrate with the aerated matrix premix. In some embodiments where the porous substrate is a wettable porous substrate, the collapsible pores can be exposed by contacting the porous substrate with an aerated matrix premix (e.g., the aerated matrix premix includes a wetting liquid).

[0123] In some embodiments, disposing the hydrated composition on the porous substrate further comprises, in step 240, mixing the matrix pre-mix or aerated matrix pre-mix while in contact with at least a portion of the substrate such that at least a portion of the hydrated composition is disposed on the substrate.

[0124] Mixing can be accomplished by a variety of techniques, including mechanical rotation (e.g., on a rotating table), mechanical stirring, immersion blending, vibrational stirring, ultrasonic stirring, or combinations thereof. In some embodiments, it may be desirable to use shear-free mixing techniques. Using shear-free mixing techniques may result in less fibrillation of the PTFE fibrils. Mixing may allow for fibrillation (stretching) of the PTFE resin into PTFE fibrils and emulsification of the PTFE resin. Mixing may allow the active particles to be homogenized within the aerated matrix premix and form catenated and / or agglomerated structures with fibrillated and / or fibrillating PTFE fibrils.

[0125] The mixing time can vary depending on the desired use of the porous substrate and / or the identity and / or amount of each component (e.g., PTFE resin, surfactant, solid particulates) in the aerated matrix premix. The mixing time can be 10 minutes or more, 1 hour or more, 3 hours or more, or 24 hours or more. The mixing time can be 48 hours or less, 24 hours or less, 3 hours or less, or 1 hour or less. In some embodiments, the mixing time is 10 minutes to 3 hours, 1 hour to 3 hours, 1 hour to 24 hours, or 3 hours to 24 hours.

[0126] In some embodiments, method 200 further includes, in optional step 265, contacting at least a portion of the substrate with a wetting liquid. In some embodiments, the wetting liquid does not include solid particles. The wetting liquid may be any liquid capable of wetting the substrate; i.e., swelling the substrate and exposing collapsible pores in the solid portion of the substrate. In some embodiments, the wetting liquid is an organic solvent such as ethanol, methanol, acetone, or acetonitrile. In some embodiments, the wetting liquid is selected so that at least one component of the solid particulates is insoluble therein. For example, in some embodiments where the solid particulates include K2CO3, the wetting liquid may be ethanol. In other embodiments, the wetting liquid is selected so that at least one component of the solid particulates is soluble in the wetting liquid. In some embodiments, the wetting liquid has the same identity as the liquid carrier of the solid particulate composition (if a liquid carrier is used). In some embodiments, the wetting liquid is different from the liquid carrier of the solid particulate composition (if a liquid carrier is used).

[0127] The amount of substrate-wetting liquid contact time may vary. In some embodiments, the substrate-wetting liquid contact time is 10 seconds or more, 30 seconds or more, 1 minute or more, 5 minutes or more, 1 hour or more, or 24 hours or more. In some embodiments, the substrate-wetting liquid contact time is 48 hours or less, 24 hours or less, 1 hour or less, 5 minutes or less, 1 minute or less, or 30 seconds or less. Without wishing to be bound by theory, it is believed that contacting at least a portion of the substrate with the wetting liquid causes the porous substrate to swell and expose collapsible pores. The wetting liquid allows at least a portion of the composition or at least a portion of one or more components of the composition to migrate into the collapsible pores of the substrate. Upon drying, the collapsible pores at least partially collapse, and the composition or components of the composition that were in the collapsible pores become embedded within the solid portion of the substrate. In some embodiments, including the step of contacting at least a portion of the substrate with a wetting fluid allows a greater amount of the composition and / or components of the composition to impregnate the pores of the substrate and / or become embedded within the substrate than would be possible if this step were not included.

[0128] The first exemplary method 200 includes, in step 250, drying the hydrated composition to form a porous substrate having the composition disposed thereon. Drying the hydrated composition includes removing at least a portion of the dispersant, at least a portion of the liquid carrier (if present), and at least a portion of the surfactant from the hydrated composition. After step 200, the porous substrate comprises a first portion of the composition disposed on at least a portion of a major surface thereof and at least a portion of a plurality of macro / micropores impregnated with a second portion of the composition. In some embodiments, after step 200, the porous substrate further comprises an embedded third portion of the composition (e.g., if the porous substrate is a wettable porous substrate and a wetting fluid was used).

[0129] Drying can be accomplished to various degrees (i.e., the amount of dispersant, liquid carrier, and / or surfactant that may be present in the porous substrate after the hydrated composition is dried) and can include various techniques as described herein (e.g., see the discussion regarding Figure 8).

[0130] In some embodiments where the substrate is contacted with a wetting fluid (step 265) and at least a portion of the solid particulates are dissolved in the wetting fluid, drying the hydrated composition can further include precipitating at least a portion of the solid particulates to form free active particles, some of which may be embedded within the solid portion of the substrate.

[0131] In some embodiments of the first exemplary method 200, the plurality of PTFE fibrils of the matrix include short-chain PTFE fibrils formed from short-chain PTFE resin and long-chain PTFE fibrils formed from long-chain PTFE resin. In such embodiments, the PTFE resin of the matrix premix and / or aerated matrix premix includes short-chain PTFE resin and long-chain PTFE resin. The PTFE resin of the aerated emulsion includes short-chain PTFE resin. Long-chain PTFE resin can be added at any step or steps of method 200 such that the PTFE resin of one or more of the emulsion, aerated emulsion (210c), matrix premix (220c), or aerated matrix premix (230c) includes short-chain PTFE resin and long-chain PTFE resin. For example, in some embodiments, method 200 further includes adding a long-chain PTFE resin to the emulsion such that the PTFE resin of the emulsion, the PTFE resin of the aerated emulsion (210c), the PTFE resin of the premix (220c), and the PTFE resin of the aerated premix (230c) comprise a short-chain PTFE resin and a long-chain PTFE resin. In some embodiments, method 200 further includes adding a long-chain PTFE resin to the aerated emulsion such that the PTFE resin of the aerated emulsion (210c), the PTFE resin of the premix (220c), and the PTFE resin of the aerated premix (230c) comprise a short-chain PTFE resin and a long-chain PTFE resin. In some embodiments, method 200 further includes adding a long-chain PTFE resin to the matrix pre-mix such that the PTFE resin of the matrix pre-mix (220c) and the PTFE resin of the aerated pre-mix (230c) comprise a short-chain PTFE resin and a long-chain PTFE resin. In some embodiments, method 200 further includes adding a long-chain PTFE resin to the aerated matrix pre-mix such that the PTFE resin of the aerated matrix pre-mix (230c) comprises a short-chain PTFE resin and a long-chain PTFE resin.

[0132] In some embodiments of method 200, the matrix premix and / or aerated matrix premix comprises at least 0.01 wt%, at least 15 wt%, at least 25 wt%, at least 45 wt%, at least 55 wt%, or at least 65 wt% PTFE resin, based on the total weight of the matrix premix or aerated matrix premix. In some embodiments of method 200, the matrix premix and / or aerated matrix premix comprises at most 80 wt%, at most 65 wt%, at most 55 wt%, at most 45 wt%, at most 25 wt%, or at most 15 wt% PTFE resin, based on the total weight of the matrix premix or aerated matrix premix.

[0133] In some embodiments of method 200, the matrix premix and / or aerated matrix premix comprises 0.01 wt.% or more, 1 wt.% or more, 5 wt.% or more, or 10 wt.% or more of the long-chain PTFE resin based on the total weight of the matrix premix or aerated matrix premix. In some embodiments of method 200, the matrix premix and / or aerated matrix premix comprises 15 wt.% or less, 10 wt.% or less, 5 wt.% or less, or 1 wt.% or less of the long-chain PTFE resin based on the total weight of the matrix premix or aerated matrix premix.

[0134] In some embodiments of method 200, the matrix premix and / or aerated matrix premix comprises at least 0.1 wt%, at least 5 wt%, at least 15 wt%, at least 25 wt%, at least 45 wt%, or at least 55 wt% short-chain PTFE, based on the total weight of the matrix premix or aerated matrix premix. In some embodiments of method 200, the matrix premix and / or aerated matrix premix comprises at most 70 wt%, at most 55 wt%, at most 45 wt%, at most 25 wt%, at most 15 wt%, or at most 5 wt% short-chain PTFE resin, based on the total weight of the matrix premix or aerated matrix premix.

[0135] 7 is a flow chart outlining a second exemplary method for disposing a composition of the present disclosure on a porous substrate to obtain a porous substrate of the present disclosure. The composition includes a matrix. The matrix includes a plurality of active particles and a plurality of PTFE fibrils formed from a plurality of PTFE resins. In some embodiments, the composition further includes free active particles, free PTFE fibrils, or both. The porous substrate includes a major surface and a plurality of macro / micropores connecting to the major surface. In some embodiments, the porous substrate is a wettable porous substrate. In some such embodiments, a plurality of collapsible pores are exposed during one or more steps of method 400.

[0136] In some embodiments, method 400 optionally includes forming a matrix premix in optional step 460A. The matrix premix (460c(A)) includes a PTFE resin, a surfactant, and a dispersant. In some embodiments, the matrix premix is ​​formed in step 460B by diluting the concentrated matrix premix with a dispersant or a solution including a dispersant and a surfactant. The concentrated matrix premix (460c(B)) includes a PTFE resin and a dispersant. In some embodiments, the concentrated matrix premix and the matrix premix include an emulsion including a PTFE resin and a dispersant. In some embodiments, the concentrated matrix premix includes at least a portion of the surfactant. In some embodiments, the concentrated matrix premix includes an emulsion of 60 wt% PTFE resin (e.g., 60 wt% short-chain PTFE resin) based on the total weight of the concentrated matrix premix.

[0137] In some embodiments, method 400 optionally includes aerating the matrix pre-mix to form an aerated matrix pre-mix at optional step 450. The matrix pre-mix (450c) includes a PTFE resin, a surfactant, and a dispersant. Aeration can be achieved using any of the techniques disclosed herein.

[0138] Method 400 includes, in step 410, contacting at least a portion of a substrate with a matrix premix or an aerated matrix premix. An aerated matrix premix is ​​an aerated matrix premix (e.g., in optional step 450, etc.). In some embodiments, it may be desirable to contact at least a portion of a substrate with a matrix premix that is not aerated (i.e., a matrix premix). In other embodiments, it may be desirable to contact at least a portion of a substrate with an aerated matrix premix (i.e., an aerated matrix premix). The substrate is contacted with the aerated matrix premix or matrix premix such that at least a portion of the major surface of the porous substrate and at least a portion of the plurality of macro / micropores connecting to the major surface are exposed to the aerated matrix premix or matrix premix. Contacting may be accomplished using any suitable technique described herein.

[0139] Contact times can vary. In some embodiments, the contact time is 10 seconds or more, 30 seconds or more, 1 minute or more, 5 minutes or more, 1 hour or more, or 24 hours or more. In some embodiments, the contact time is 48 hours or less, 24 hours or less, 1 hour or less, 5 minutes or less, 1 minute or less, or 30 seconds or less.

[0140] The method 400 includes contacting at least a portion of a substrate with a solid particulate composition. The solid particulate composition includes solid particulates. In some embodiments, the solid particulate composition includes solid particulates and a liquid carrier. In some embodiments, the porous substrate is a wettable porous substrate, the liquid carrier includes a wetting liquid. In such embodiments, the wetting liquid exposes a plurality of collapsible pores in the wettable porous substrate. The liquid carrier can include water; an organic solvent such as ethyl acetate, ethanol, methanol, isopropanol, butanol, dichloromethane, toluene, acetonitrile, acetone, diethyl ether, amyl alcohol, or tetrahydrofuran; or a combination thereof.

[0141] The solid particulates may include one or more species for forming one or more different types of active particles (e.g., activated carbon and potassium carbonate). In some such embodiments, at least one component and / or at least a portion of the solid particulates in the solid particulate composition are dissolved in a liquid carrier (e.g., a wetting liquid). In other embodiments, the solid particulates of the solid composition are suspended in a liquid carrier. In still other embodiments, a first portion of the solid particulates are dissolved in a liquid carrier and a second portion of the solid particulates are suspended in the liquid carrier. For example, the solid particulate composition may include a first chemical species dissolved in a liquid carrier and a second chemical species suspended in the liquid carrier.

[0142] At least a portion of the first plurality of active particles, at least a portion of the free active particles (if present), or both comprise at least a portion of solid particulates. In embodiments, at least a portion of the substrate is contacted with the solid particulate composition without a liquid carrier; i.e., the solid particulate composition comprises 100% by weight of solid particulates. In some such embodiments, contacting can be achieved by disposing the solid particulates on at least a portion of the substrate. In other embodiments, the solid particulate composition comprises solid particulates and a liquid carrier. In such embodiments, contacting at least a portion of the substrate with the solid particulate composition can be achieved using any suitable technique described herein.

[0143] In embodiments where the solid particulate composition comprises a liquid carrier, the solid particulate composition comprises 0.5% by weight or more, 10% by weight or more, 30% by weight or more, or 50% by weight or more of solid particulates, based on the total weight of the solid particulate composition. In embodiments where the solid particulate composition comprises a liquid carrier, the solid particulate composition comprises 90% by weight or less, 50% by weight or less, 30% by weight or less, or 10% by weight or less of solid particulates, based on the total weight of the solid particulate composition.

[0144] The amount of substrate-solid particulate composition contact time can vary. In some embodiments, the substrate-solid particulate composition contact time is 10 seconds or more, 30 seconds or more, 1 minute or more, 5 minutes or more, 1 hour or more, or 24 hours or more. In some embodiments, the substrate-solid particulate composition contact time is 48 hours or less, 24 hours or less, 1 hour or less, 5 minutes or less, 1 minute or less, or 30 seconds or less.

[0145] In some embodiments, the step of contacting at least a portion of the substrate with the matrix premix or the aerated matrix premix is ​​performed before the step of contacting at least a portion of the substrate with the solid particulate composition (i.e., step 410 is performed before step 420). In some embodiments, the step of contacting at least a portion of the substrate with the solid particulate composition is performed before the step of contacting at least a portion of the substrate with the matrix premix or the aerated matrix premix (i.e., step 420 is performed before step 410). Generally, upon contacting the substrate with the matrix premix, the aerated matrix premix, or the solid particulate composition, at least a portion of the substrate becomes saturated with (e.g., is still in contact with) the matrix premix, the aerated matrix premix, or the solid particulate composition. For example, at least a portion of the substrate can be contacted with a large amount of the matrix premix, the aerated matrix premix, or the solid particulate composition; thereafter, the substrate is removed from the large amount of the matrix premix, the aerated matrix premix, or the solid particulate composition. Depending on the absorbent / adsorbent properties of some substrates, a portion of the bulk matrix premix, aerated matrix premix, or solid particulate composition may be adsorbed / absorbed onto the surface of the substrate and / or within the pores (e.g., macropores / micropores and / or collapsible pores) of the substrate. Thus, at least a portion of the substrate is in contact with the bulk matrix premix, aerated matrix premix, or solid particulate composition during the subsequent contacting step. For example, in some embodiments, at least a portion of the substrate is immersed in the bulk matrix premix or aerated matrix premix; removed from the bulk matrix premix or aerated matrix premix; and then, while at least a portion of the substrate is saturated with the bulk matrix premix or a portion of the aerated matrix premix, contacted with the bulk solid particulate composition.In some embodiments, at least a portion of the substrate is contacted with a quantity of the solid particulate composition; removed from the quantity of the solid particulate composition; and then contacted with a quantity of the matrix premix or aerated matrix premix while at least a portion of the substrate is saturated with a portion of the quantity of the solid particulate composition.

[0146] In some embodiments, the step of contacting at least a portion of the substrate with the matrix premix or the aerated matrix premix (step 410) is performed simultaneously with the step of contacting at least a portion of the substrate with the solid particulate composition (step 420). That is, at least a portion of the substrate is contacted with a large amount of the matrix premix or the aerated matrix premix at the same time that at least a portion of the substrate is contacted with a large amount of the solid particulate composition. For example, at least a portion of the substrate may be first immersed in a large amount of the matrix premix or the aerated matrix premix; then, while at least a portion of the substrate is still immersed in the large amount of the matrix premix or the aerated matrix premix, a large amount of the solid particulate composition may be pumped through or around at least a portion of the substrate. In some embodiments, at least a portion of the substrate may be first immersed in a large amount of the solid particulate composition; then, while at least a portion of the substrate is still immersed in the large amount of the solid particulate composition, a large amount of the matrix premix or the aerated matrix premix may be pumped through or around at least a portion of the substrate.

[0147] Without wishing to be bound by theory, it is believed that contacting the substrate with the solid particulate composition allows free active particles (if present) to be embedded within at least a portion of the plurality of collapsible pores of the substrate. It is also believed that contacting the substrate with the solid particulate composition allows for increased adhesion between the composition and the substrate. Furthermore, it is believed that contacting the substrate with the solid particulate composition immobilizes a larger amount of chemically active adsorbent within the substrate than when the chemical adsorbent is impregnated into a support and then the hybrid material is supported on the substrate, thereby increasing the absorption capacity of acidic or basic gases.

[0148] In some embodiments, the step of contacting at least a portion of the substrate with the matrix premix or the aerated matrix premix (step 410) and the step of contacting at least a portion of the substrate with the solid particulate composition (step 420) may be repeated multiple times (e.g., two, three, four, etc.) consecutively or as individual steps. For example, at least a portion of the substrate may be contacted with the matrix premix or the aerated matrix premix, with the solid particulate composition, and then with the matrix premix or the aerated matrix premix a second time. In other embodiments, at least a portion of the substrate may be contacted with the matrix premix or the aerated matrix premix, with the first solid particulate composition, with the first solid particulate composition a second time, or with a second solid particulate composition, a third solid particulate composition, etc. In some such embodiments, the composition of the first solid particulate composition is different from the composition of the first solid particulate composition. In some embodiments, the composition of the second solid particulate composition is the same as the composition of the first solid particulate composition.

[0149] In some embodiments, the matrix premix or aerated matrix premix of method 400 further comprises second solid particulates (i.e., the solid particulates in the solid particulate composition are first solid particulates). The amount of second solid particulates can vary depending on the identity of the second solid particulates and the desired end use of the porous substrate. In some embodiments, the matrix premix or aerated matrix premix comprises 0.5% or more, 10% or more, or 30% or more by weight of the second solid particulates, based on the total weight of the matrix premix or aerated matrix premix. In some embodiments, the matrix premix or aerated matrix premix comprises 50% or less, 30% or less, or 10% or less by weight of the second solid particulates, based on the total weight of the matrix premix or aerated matrix premix. The plurality of active particles, the free active particles, or both may comprise a portion of the second solid particulates.

[0150] In some embodiments, the first solid particulate and the second solid particulate are made of the same material. In some embodiments, the first solid particulate and the second solid particulate are made of different materials.

[0151] In some embodiments, method 400 further includes, in optional step 425, contacting at least a portion of the substrate with a wetting liquid. The wetting liquid may be any liquid capable of wetting the substrate, i.e., swelling the substrate and exposing collapsible pores in the solid portion of the substrate. In some embodiments, the wetting liquid is an organic solvent such as ethanol, methanol, acetone, or acetonitrile. In some embodiments, the wetting liquid is selected so that at least one component of the solid particulates does not dissolve therein. For example, in some embodiments where the solid particulates include K2CO3, the wetting liquid may be ethanol. In some embodiments, the wetting liquid has the same identity as the liquid carrier of the solid particulate composition (if a liquid carrier is used). In some embodiments, the wetting liquid is different from the liquid carrier of the solid particulate composition (if a liquid carrier is used).

[0152] In some embodiments, step 425 occurs after completion of step 410 and step 420 (which may occur in either order). In some such embodiments, the order of steps is step 410, step 420, then step 425. In other such embodiments, the order of steps is step 420, step 310, then step 425. In some embodiments, step 425 occurs after completion of one of steps 410 or 420, but before completion of any steps that have not yet been completed. In some embodiments, at least a portion of the substrate can be contacted with the same dampening fluid or one or more different dampening fluids before and / or after completion of other steps of the method (e.g., step 420 and step 410).

[0153] The amount of substrate-wetting liquid contact time can vary. In some embodiments, the substrate-wetting liquid contact time is 10 seconds or more, 30 seconds or more, 1 minute or more, 5 minutes or more, 1 hour or more, or 24 hours or more. In some embodiments, the substrate-wetting liquid contact time is 48 hours or less, 24 hours or less, 1 hour or less, 5 minutes or less, 1 minute or less, or 30 seconds or less.

[0154] Without wishing to be bound by theory, it is believed that contacting at least a portion of the substrate with a wetting liquid can cause the porous substrate to swell and expose collapsible pores. The wetting liquid can migrate at least a portion of the composition or at least a portion of one or more components of the composition into the collapsible pores of the substrate. Upon drying, the collapsible pores at least partially collapse, and the composition or components of the composition that were in the collapsible pores become embedded within the solid portion of the substrate. In some embodiments, including the step of contacting at least a portion of the substrate with a wetting liquid can cause a greater amount of the composition and / or components of the composition to impregnate the pores of the substrate and / or become embedded within the substrate than without the step.

[0155] Method 400 includes, in step 430, disposing a hydrated composition on a porous substrate. The hydrated composition includes a matrix, free active particles (if present), free PTFE fibrils (if present), at least a portion of a dispersing agent, at least a portion of a liquid carrier (if present), at least a portion of a wetting liquid (if present), and at least a portion of a surfactant. The hydrated composition may be disposed on at least a portion of at least one major surface of the substrate, may be impregnated into at least a portion of a plurality of macro / micropores of the substrate, may be intercalated within collapsible pores of the substrate, or any combination thereof.

[0156] Method 400 includes drying the hydrated composition to form a porous substrate having the composition disposed thereon. Drying the hydrated composition includes removing at least a portion of the dispersant, at least a portion of the liquid carrier (if present), and at least a portion of the surfactant from the hydrated composition. Drying can be accomplished to various extents (i.e., the amount of dispersant, liquid carrier, and / or surfactant present in the porous substrate after drying) and can include various techniques, such as those discussed herein (see, e.g., the discussion regarding FIG. 8).

[0157] In some embodiments where the solid particulate composition of the substrate comprises components of the solid particulates and / or a portion of the solid particulates dissolved in a liquid carrier, and / or the substrate has been contacted with a wetting liquid comprising a wetting liquid capable of dissolving some components of the solid particulates, drying the hydrated composition can further comprise precipitating at least a portion of the solid particulates to form free active particles, some of which may be embedded within the solid portion of the substrate.

[0158] In some embodiments of method 400, the plurality of PTFE fibrils of the matrix include short-chain PTFE fibrils formed from short-chain PTFE resin and long-chain PTFE fibrils formed from long-chain PTFE resin. In such embodiments, the PTFE resin of aerated matrix premix (410c) or matrix premix (410c) includes short-chain PTFE resin and long-chain PTFE resin. The PTFE resin of concentrated matrix premix includes short-chain PTFE. Long-chain PTFE resin can be added at any step or steps of method 400 such that the PTFE resin of one or more of concentrated matrix premix (460c(B)), matrix premix (460c(A)), and aerated matrix premix (450c) includes short-chain PTFE resin and long-chain PTFE resin. For example, in some embodiments, method 400 further includes adding a long-chain PTFE resin to the concentrated matrix premix such that the PTFE resin of the concentrated matrix premix, the PTFE resin of matrix premix (450c), and the PTFE resin of aerated matrix premix (450c) comprise a short-chain PTFE resin and a long-chain PTFE resin. In some embodiments, method 400 further includes adding a long-chain PTFE resin to the matrix premix such that the PTFE resin of premix (460c) and the PTFE resin of aerated premix (450c) comprise a short-chain PTFE resin and a long-chain PTFE resin. In some embodiments, method 400 further includes adding a long-chain PTFE resin to the aerated matrix premix such that the PTFE resin of aerated matrix premix (450c) comprises a short-chain PTFE resin and a long-chain PTFE resin.

[0159] In some embodiments of method 400, the aerated matrix premix or matrix premix comprises 0.01% or more, 15% or more, 25% or more, 45% or more, 55% or more, or 65% or more by weight of PTFE resin, based on the total weight of the aerated matrix premix or matrix premix. In some embodiments of method 400, the aerated matrix premix or matrix premix comprises 80% or less, 65% or less, 55% or less, 45% or less, 25% or less, or 15% or less by weight of PTFE resin, based on the total weight of the aerated matrix premix or matrix premix.

[0160] In some embodiments of method 400, the aerated matrix premix or matrix premix comprises 0.01 wt.% or more, 1 wt.% or more, 5 wt.% or more, or 10 wt.% or more of a long-chain PTFE resin based on the total weight of the aerated matrix premix or matrix premix. In some embodiments of method 400, the aerated matrix premix or matrix premix comprises 15 wt.% or less, 10 wt.% or less, 5 wt.% or less, or 1 wt.% or less of a long-chain PTFE resin based on the total weight of the aerated matrix premix or matrix premix.

[0161] In some embodiments of method 400, the aerated matrix premix or matrix premix comprises 0.1 wt.% or more, 5 wt.% or more, 15 wt.% or more, 25 wt.% or more, 45 wt.% or more, or 55 wt.% or more short-chain PTFE, based on the total weight of the aerated matrix premix or matrix premix. In some embodiments of method 400, the aerated matrix premix or matrix premix comprises 80 wt.% or less, 55 wt.% or less, 45 wt.% or less, 25 wt.% or less, 15 wt.% or less, or 5 wt.% or less short-chain PTFE resin, based on the total weight of the aerated matrix premix or matrix premix.

[0162] At any point during any of the methods of the present disclosure, a dispersing agent may be added to a component of a concentrated matrix premix, an aerated emulsion, a matrix premix, an aerated matrix premix, or a combination thereof. In some embodiments, a dispersing agent may be added before or during any one of the steps of the methods disclosed herein. For example, in embodiments in which a long-chain PTFE resin is added to a concentrated matrix premix, an emulsion, an aerated emulsion, a matrix premix, or an aerated matrix premix, the long-chain PTFE resin may be added to the mixture containing the dispersing agent. A dispersing agent may be added to dilute a component, suspend a component, promote the formation of a colloid containing one or more components, promote the formation of an emulsion, promote aeration, or a combination thereof. For example, in some embodiments, a dispersing agent may be added to an aerated emulsion (e.g., 210c). In some embodiments, a dispersing agent may be added to a matrix premix (e.g., 220c and 460c). In some embodiments, a dispersing agent may be added to an aerated matrix premix (e.g., 230c and 450c). In some embodiments, a dispersant may be added to the mixture. In some embodiments, a dispersant may be added to the emulsion (e.g., 210c).

[0163] The disclosed method includes drying the hydrated composition to form a composition disposed on an injection substrate. Drying the hydrated composition includes removing at least a portion of the dispersant and / or liquid carrier (if present) from the hydrated composition. Drying the hydrated composition also includes removing at least a portion of the surfactant from the hydrated composition. The porous substrate formed after drying the hydrated composition contains 50% by weight or less, 20% by weight or less, 10% by weight or less, 5% by weight or less, or 1% by weight or less of the dispersant and / or liquid carrier (if present) based on the total weight of the porous substrate. The porous substrate formed after drying the hydrated composition contains 50% by weight or less, 20% by weight or less, 10% by weight or less, 5% by weight or less, or 1% by weight or less of the surfactant based on the total weight of the porous substrate. The extent of drying can vary depending on the desired use of the porous substrate and / or subsequent processing steps.

[0164] The dispersant in any one of the exemplary methods may be water, one or more organic solvents, or both. In some embodiments, the dispersant comprises water. In some embodiments, the dispersant comprises an organic solvent or a mixture of organic solvents. Examples of organic solvents that may be included in the dispersant include methanol, acetone, tetrahydrofuran, dimethylformamide, acetonitrile, isopropanol, ethanol, or a combination thereof.

[0165] Figure 8 is a flow chart outlining the steps of various drying techniques and / or methods. In some embodiments, a hydrated composition is formed upon contact with a solution of excess dispersant, liquid carrier (if present), and surfactant; i.e., the hydrated composition is removed from an aerated matrix premix, matrix premix, or solid particulate composition. In such embodiments, drying the hydrated composition comprises separating the hydrated composition from the remaining aerated matrix premix, matrix premix, or solid particulate composition, in step 500. This can be accomplished by decanting the aerated matrix premix, matrix premix, or solid particulate composition; or by physically removing the hydrated composition from the aerated matrix premix, matrix premix, or solid particulate composition.

[0166] In some embodiments, drying the hydrated composition includes contacting at least a portion of the hydrated composition (e.g., a portion of a major surface of a porous substrate on which the hydrated composition is disposed), preferably the entire hydrated composition, with an absorbent material. The absorbent material can extract at least a portion of the dispersant, at least a portion of the surfactant, and at least a portion of the liquid carrier (if present) from the hydrated composition. Any suitable absorbent material can be used. Examples of absorbent materials include cotton; cellulose; sponges comprising polyester, polyurethane, vegetable cellulose, melamine, or combinations thereof; anhydrous calcium chloride; anhydrous magnesium sulfate; sodium polyacrylate; and combinations thereof. The hydrated composition may be in contact with the absorbent material for a period of time. In some embodiments, the contact time is 1 second or more, 1 minute or more, or 1 hour or more. In some embodiments, the contact time is 24 hours or less, 1 hour or less, or 1 minute or less. In such embodiments, the method further includes removing at least a portion, preferably all, of the absorbent material from the hydrated composition in step 520.

[0167] In some embodiments, the hydrated composition is contacted with the absorbent material more than once. In other words, in some embodiments, the steps of contacting at least a portion of the hydrated composition with an absorbent (step 510) and removing at least a portion of the absorbent material from the hydrated composition (step 520) are repeated several times in succession (e.g., 2-10 times, 2-20 times, or 2-50 times), each time using an absorbent material that has not previously been contacted with the hydrated composition (i.e., a new absorbent material).

[0168] In some embodiments, drying the hydrated composition in step 540 further comprises exposing the hydrated composition to an elevated temperature for a period of time. In some embodiments, the hydrated composition is exposed to a temperature of 100°C to 400°C, preferably 100°C to 300°C, for a period of 0.1 hours to 24 hours, preferably 1 hour to 5 hours. Preferably, the hydrated composition is not subjected to calcination conditions. PTFE fibrils may shrink under calcination conditions (e.g., temperatures above 330°C), which may manifest as rupture of the PTFE fibrils and a reduction in the mechanical stability of the matrix.

[0169] In some embodiments, drying the hydrated composition to form the matrix further comprises applying a vacuum to the hydrated composition, hi some such embodiments, the hydrated composition is simultaneously exposed to an elevated temperature (e.g., 25°C to 150°C).

[0170] The surfactant of any of the exemplary methods may be a nonionic non-fluorinated surfactant. A nonionic surfactant is a surfactant with an uncharged polar head group. Examples of nonionic non-fluorinated surfactants that may be used include ethoxylates, alkoxylates, and cocamides. In some embodiments, the surfactant is polyethylene glycol trimethylnonyl ether. In some embodiments, the aerated matrix premix and / or matrix premix contains 0.5 wt. % or more, 5 wt. % or more, or 20 wt. % or more surfactant, based on the total weight of the aerated matrix premix or matrix premix. In some embodiments, the aerated matrix premix and / or matrix premix contains 40 wt. % or less, 20 wt. % or less, or 5 wt. % or less surfactant, based on the total weight of the aerated matrix premix or matrix premix. The aerated matrix premix or matrix premix of any one of the exemplary methods may contain 0.5 wt. % to 40 wt. %, preferably 5 wt. % to 20 wt. % surfactant, based on the total weight of the aerated matrix premix or matrix premix.

[0171] The method of the present disclosure can result in various loading capacities of multiple active particles. The loading capacity of each solid particulate (or any individual component of the solid particulate) can be calculated according to a composition analysis test method (i.e., a loading capacity test method). The sum of the loading capacities of each component of the solid particulate is considered to be the loading capacity of multiple active particles containing the components of the solid particulate. For example, if the solid particulate includes activated carbon, the loading capacity of the activated carbon is the loading capacity of multiple active particles containing activated carbon. If the solid particulate includes manganese oxide and copper oxide, the loading capacity of multiple active particles containing manganese oxide and copper oxide is the sum of the loading capacity of the manganese oxide and the loading capacity of the copper oxide.

[0172] The total active particle loading capacity is the sum of the loading capacity of one or more components comprising the plurality of active particles and free active particles (if present). For example, in some embodiments, the plurality of active particles and free active particles (if present) comprise manganese oxide and copper oxide, and the total active particle loading capacity is the sum of the loading capacities of the manganese oxide and copper oxide. In some embodiments, the disclosed methods result in a total active particle loading capacity of 50 wt% or more, 70 wt% or more, 80 wt% or more, or 90 wt% or more. In some embodiments, the disclosed methods result in a plurality of active particle loading capacities of 95 wt% or less, 90 wt% or less, 80 wt% or less, or 70 wt% or less.

[0173] Illustrative Embodiments Throughout the exemplary embodiments, the term "macro / micropore" is understood to refer to a macropore or macropores, a micropore or micropores (if present), or both.

[0174] Porous Substrate Embodiments Embodiment 1C is a porous substrate having disposed thereon a composition, the composition comprising a matrix, the matrix comprising a plurality of PTFE fibrils and a plurality of active particles. In some embodiments, the plurality of PTFE fibrils comprises short-chain PTFE fibrils and long-chain PTFE fibrils.

[0175] Embodiment 2C is the porous substrate of embodiment 1C, wherein the composition further comprises free active particles, free PTFE fibrils, or both. In some embodiments, the free PTFE fibrils comprise short-chain PTFE fibrils. In some embodiments, the plurality of active particles and the free active particles comprise the same material. In other embodiments, the plurality of active particles and the free active particles comprise different materials.

[0176] Embodiment 3C is a porous substrate of embodiment 1C or 2C, wherein the porous substrate comprises a major surface and a plurality of macropores connecting the major surface; a first portion of the composition is disposed on at least a portion of the major surface; and at least a portion of the plurality of macropores is impregnated with a second portion of the composition.

[0177] Embodiment 4C is a porous substrate of embodiment 3C, wherein a portion of the plurality of macro / micropores comprises a first portion of the macro / micropores; the first portion of the macro / micropores are impregnated with a first component of the composition; and a second portion of the macro / micropores are impregnated with a second component of the composition.

[0178] Embodiment 5C is the porous substrate of embodiment 4C, wherein the first component and the second component are a matrix, at least one particle of free active particles, or at least one PTFE fibril of free PTFE fibrils. In some embodiments, the first component is the matrix or composition as a whole, and the second component is at least one particle of free active particles.

[0179] Embodiment 6C is the porous substrate of any one of Embodiments 1C through 5C, wherein the porous substrate is a wettable porous substrate.

[0180] Embodiment 7C is the porous substrate of embodiment 6C, wherein the porous substrate comprises a third portion of the composition embedded within the porous substrate (e.g., embedded within a solid portion of the porous substrate).

[0181] Embodiment 8C is the porous substrate of embodiment 7C, wherein the porous substrate comprises one or more components of the composition embedded therein. The one or more components may be a portion of the matrix, at least one particle of the free active particles, at least one PTFE fibril of the free PTFE fibrils, or any combination thereof. In some embodiments, the one or more components comprise free PTFE fibrils. In some such embodiments, the free PTFE fibrils comprise long-chain PTFE fibrils.

[0182]

[0023] Embodiment 9C is the porous substrate of any one of Embodiments 1C-8C, wherein the porous substrate is made from a material comprising a reticulated foam. The reticulated foam may be polymer-based; metal-, metal oxide-, or metal carbide-based; carbon-based; ceramic-based; or any combination thereof. The reticulated foam may include reticulated polyester; reticulated polyether; reticulated polyurethane; reticulated polyurethane without heat treatment; reticulated cellulose; reticulated melamine; reticulated steel; reticulated activated carbon; reticulated vitreous carbon; reticulated graphene; reticulated foam made from a metal, such as a reduced metal (such as titanium, lead, iron, copper, zinc, chromium, cobalt, nickel, manganese, gold, silver, platinum, palladium, rhodium, tungsten, molybdenum, vanadium, zirconium, silicon, ruthenium, or any combination thereof); reticulated silicon oxide; reticulated silicon carbide; or any combination thereof.

[0183] Embodiment 10C is a porous substrate of any one of Embodiments 1C-9C, wherein at least a portion of the plurality of active particles and at least a portion of the plurality of PTFE fibrils adopt a catenated structure, an aggregated structure, or both.

[0184] Embodiment 11C is the porous substrate of any one of Embodiments 1C-10C, wherein the short-chain PTFE fibrils, long-chain PTFE fibrils, free PTFE fibrils (if present), or any combination thereof, comprise C3-PTFE, C2-PTFE, C1-PTFE, or a combination thereof.

[0185] Embodiment 12C is the porous substrate of any one of Embodiments 1C to 11C, wherein the plurality of active particles, the free active particles (if present), or both, comprise a catalyst, an adsorbent, a growth seed, a metal-organic framework (MOF), an electroactive material, a bioactive substance, or any combination thereof.

[0186] Embodiment 13C is a porous substrate according to embodiment 12C, wherein the plurality of active particles comprises a catalyst, the catalyst being capable of decomposing ozone.

[0187] Embodiment 14C is the porous substrate of embodiment 11C or 12C, wherein the plurality of active particles, free active particles (if present), or both, comprise a catalyst; and the catalyst is capable of nitrobenzene reduction, hydrogenation, NOx reduction, or a combination thereof.

[0188] Embodiment 15C is the composition of embodiment 13C, wherein the plurality of active particles comprises a catalyst; the catalyst comprises iron silicate, iron manganese silicate, zinc iron silicate, or any combination thereof; a transition metal oxide such as zinc oxide, manganese oxide, copper oxide, cerium dioxide, or any combination thereof; a reduced metal (i.e., a zero-valent metal) comprising titanium, lead, iron, copper, zinc, chromium, cobalt, nickel, manganese, gold, silver, platinum, palladium, rhodium, tungsten, molybdenum, vanadium, zirconium, silicon, ruthenium, or any combination thereof; a carbonate such as barium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, or any combination thereof; or any combination thereof.

[0189] Embodiment 16C is the porous substrate of embodiment 12C, wherein the plurality of active particles, the free active particles (if present), or both, comprise an adsorbent; and the adsorbent is a physisorbent, a chemisorbent, or a physisorbent-chemisorbent hybrid. In some embodiments, the physisorbent-chemisorbent hybrid is a grafted hybrid or an impregnated hybrid.

[0190] Embodiment 17C is a porous substrate according to embodiment 16C, wherein the plurality of active particles, free active particles (if present), or both, comprise an adsorbent; the adsorbent is capable of adsorbing a basic compound, an acidic compound, an organic compound, an inorganic compound, or any combination thereof. The acidic compound, basic compound, organic compound, inorganic compound, or any combination thereof may be in a liquid state, a gaseous and / or vapor state (preferably), or both.

[0191] Embodiment 18C is a porous substrate according to embodiment 17C, wherein the adsorbent is capable of adsorbing a basic compound. The basic compound may be in a liquid state, a gaseous state, and / or a vapor state (preferably), or both. In some such embodiments, the adsorbent comprises a chemical adsorbent comprising an inorganic acid (e.g., boric acid, nitric acid, sulfuric acid, hydrochloric acid, hydrogen chloride, hydrogen fluoride, hydrogen bromide, phosphoric acid, perchloric acid, periodic acid, or any combination thereof) or a carboxylic acid functional group (e.g., citric acid, terephthalic acid, trimesic acid, tartaric acid, maleic acid, benzoic acid, oxalic acid, or any combination thereof). In some embodiments, the basic compound comprises ammonia.

[0192] Embodiment 19C is the porous substrate of embodiment 17C, wherein the adsorbent is capable of adsorbing an acidic compound. The acidic compound may be in a liquid state, a gaseous state and / or a vapor state (preferably), or both. In some embodiments, the acidic compound comprises sulfur dioxide, nitrogen dioxide, hydrogen sulfide, sulfur trioxide, nitric oxide, or any combination thereof.

[0193] Embodiment 20C is a porous substrate according to embodiment 17C, wherein the adsorbent is capable of adsorbing inorganic compounds. The inorganic compounds may be in a liquid state, a gaseous state, and / or a vapor state (preferably), or both. In some such embodiments, the adsorbent comprises activated carbon, a zeolite (e.g., zeolite X, zeolite A, zeolite Y, zeolite beta, and zeolite ZsM-5), a silicate, a metal-organic framework (MOF), a mesoporous transition metal oxide, or any combination thereof. In some embodiments, the inorganic compounds comprise carbon dioxide; carbon monoxide; water; perfluorocarbons (e.g., tetrafluoromethane and hexafluoroethane); sulfur hexafluoride; hydrogen sulfide; nitrogen oxides; sulfur oxides; ozone; or any combination thereof.

[0194] Embodiment 21C is a porous substrate described in embodiment 17C, wherein the adsorbent is capable of adsorbing an organic compound. The organic compound may be in a liquid state, a gaseous and / or vapor state (preferably), or both. The organic compound may include aromatic hydrocarbons (e.g., toluene, benzene, xylene, and ethylbenzene); siloxanes; polycyclic aromatic hydrocarbons (e.g., naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)fluoranthene, dibenzo(a,h)anthracene, benzo(ghi)perylene, and indeno(1,2,3-cd)pyrene); n-alkanes (e.g., methane, ethane, propane, butane, pentane, and hexane); n-alkenes (e.g., methylene, ethylene, and propylene); aldehydes (e.g., formaldehyde); alcohols; siloxanes; or any combination thereof. In some such embodiments, the catalyst comprises activated carbon, a zeolite (e.g., zeolite X, zeolite A, zeolite Y, zeolite beta, and zeolite ZSM-5), a silicate, a metal-organic framework (MOF), a mesoporous transition metal oxide, or any combination thereof.

[0195] Embodiment 22C is the porous substrate of any one of embodiments 16C to 21C, wherein the adsorbent is a chemisorbent, a physisorbent, or a physisorbent-chemisorbent hybrid; and the physisorbent comprises activated carbon, a zeolite, a silicate, a metal-organic framework (MOF), a mesoporous transition metal oxide, or a combination thereof.

[0196] Embodiment 23C is the porous substrate of embodiment 19C, wherein the adsorbent comprises a chemical adsorbent or a hybrid physical adsorbent-chemical adsorbent, and the chemical adsorbent comprises a Group I metal carbonate; a metal oxide; a Group I metal hydroxide; a Group II metal hydroxide; an N-containing compound such as an amine, an imine, an ammonium salt, and combinations thereof; or combinations thereof. In some embodiments, the N-containing compound comprises polyethyleneimine, tetraethylenepentamine, ethylenediamine, 3-aminopropyltriethoxysilane, ammonium persulfate, or combinations thereof.

[0197] Embodiment 24C is the porous substrate of embodiment 12C, wherein the plurality of active particles, the free active particles (if present), or both, comprise growth seeds; the growth seeds are nucleation points for the growth of a metal-organic framework (MOF). In some embodiments, the growth seeds comprise copper nitrate, trimesic acid, or both.

[0198] Embodiment 25C is the porous substrate of embodiment 12C, wherein the plurality of active particles, the free active particles (if present), or both, comprise a MOF; and the MOF comprises copper benzene-1,3,5-tricarboxylate.

[0199] Embodiment 26C is the porous substrate of embodiment 12C, wherein the plurality of active particles comprises an electroactive material; and the electroactive material is an anode electroactive material, a cathode electroactive material, or both.

[0200] Embodiment 27C is the composition of embodiment 12C or 26C, wherein the electroactive material comprises lithium, or lithium and one or more metals.

[0201] Embodiment 28C is the porous substrate of embodiment 12C, wherein the plurality of active particles comprises a biologically active material. The biologically active material can be a protein, lipid, nucleotide, nucleic acid, sugar, polysaccharide, or any combination thereof. The protein can be an enzyme. The enzyme can be lactase.

[0202] Embodiment 29C is the porous substrate of any one of Embodiments 1C-28C, wherein the plurality of active particles, free active particles (if present), or both, have an average particle size of 0.001 μm or more, 0.01 μm or more, 0.1 μm or more, 1 μm or more, 5 μm or more, 10 μm or more, or 100 μm or more, as measured according to the Dimensional Analysis Test Method. The plurality of active particles, free active particles (if present), or both, may have an average particle size of 500 μm or less, 100 μm or less, 10 μm or less, or 1 μm or less, as measured according to the Dimensional Analysis Test Method. In some embodiments where the plurality of active particles, free active particles (if present) comprises a catalyst, the average particle size is 0.001 μm to 5 μm, 0.001 μm to 1 μm, or 0.001 μm to 0.1 μm, as measured according to the Dimensional Analysis Test Method. In some embodiments where the plurality of active particles, free active particles (if present) comprise an adsorbent, the average particle size is between 0.001 μm and 100 μm, between 1 μm and 100 μm, or between 0.001 μm and 0.1 μm, as measured according to the Dimensional Analysis Test Method.

[0203] Embodiment 30C is the porous substrate of any one of Embodiments 1C to 29C, wherein the short-chain PTFE fibrils can have an average length of 30 μm or less, 20 μm or less, 10 μm or less, or 5 μm or less, as measured according to the Dimensional Analysis Test Method. The short-chain PTFE fibrils can have an average length of 1 μm or more, 5 μm or more, 10 μm or more, or 20 μm or more, as measured according to the Dimensional Analysis Test Method.

[0204] Embodiment 31C is the porous substrate of any one of Embodiments 1C-29C, wherein the long-chain PTFE fibrils can have an average length of 40 μm or more, 100 μm or more, 150 μm or more, 250 μm or more, 500 μm or more, or 1000 μm or more, as measured according to the Dimensional Analysis Test Method. The long-chain PTFE fibrils can have an average length of 2000 μm or less, 1000 μm or less, 700 μm or less, 500 μm or less, 250 μm or less, 150 μm or less, or 100 μm or less, as measured according to the Dimensional Analysis Test Method.

[0205] Embodiment 32C is the porous substrate of any one of Embodiments 1C-31C, wherein the short-chain PTFE fibrils can have an average diameter of 0.01 μm or more, 0.05 μm or more, 0.3 μm or more, or 0.5 μm or more, as measured according to the Dimensional Analysis Test Method. The short-chain PTFE fibrils can have an average diameter of 1 μm or less, 0.5 μm or less, or 0.3 μm or less, as measured according to the Dimensional Analysis Test Method.

[0206] Embodiment 33C is the porous substrate of any one of Embodiments 1C-32C, wherein the long-chain PTFE fibrils can have an average diameter of 100 μm or less, 50 μm or less, 10 μm or less, or 1 μm or less, as measured according to the Dimensional Analysis Test Method. The long-chain PTFE fibrils can have an average diameter of 0.5 μm or more, 1 μm or more, 10 μm or more, or 50 μm or more, as measured according to the Dimensional Analysis Test Method.

[0207] Embodiment 34C is the porous substrate of any one of Embodiments 1C-33C, wherein the substrate having the composition disposed thereon comprises at least 0.001 wt.%, at least 0.01 wt.%, at least 0.1 wt.%, at least 5 wt.%, at least 10 wt.%, at least 20 wt.%, at least 30 wt.%, at least 40 wt.%, at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, or at least 95 wt.% porous substrate, as calculated according to the Compositional Analysis Test Method based on the total substrate-composition weight (the total weight of the substrate and the composition disposed thereon). In some embodiments, the porous substrate having the composition disposed thereon comprises 99% by weight or less, 95% by weight or less, 90% by weight or less, 80% by weight or less, 70% by weight or less, 60% by weight or less, 50% by weight or less, 40% by weight or less, 30% by weight or less, 20% by weight or less, 10% by weight or less, 5% by weight or less, 1% by weight or less, or 0.01% by weight or less of the porous substrate, based on the total weight of the substrate-composition, calculated according to the Compositional Analysis Test Method.

[0208] Embodiment 35C is the porous substrate of any one of Embodiments 1C-34C, wherein the substrate having the composition disposed thereon comprises at least 0.001 wt%, at least 0.01 wt%, at least 0.1 wt%, at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, or at least 95 wt% of the composition, calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition. In some embodiments, the substrate having the composition disposed thereon comprises 99% by weight or less, 95% by weight or less, 90% by weight or less, 80% by weight or less, 70% by weight or less, 60% by weight or less, 50% by weight or less, 40% by weight or less, 30% by weight or less, 20% by weight or less, 10% by weight or less, 5% by weight or less, 1% by weight or less, or 0.01% by weight or less of the composition, calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition.

[0209] Embodiment 36C is the porous substrate of any one of Embodiments 1C-35C, wherein the composition comprises at least 0.1%, at least 5%, at least 15%, at least 25%, at least 45%, at least 55%, at least 65%, or at least 80% by weight of a plurality of PTFE fibrils, calculated according to the Compositional Analysis Test Method, based on the total weight of the composition. The composition may comprise no more than 95%, no more than 80%, no more than 65%, no more than 55%, no more than 45%, no more than 25%, no more than 15%, or no more than 5% by weight of a plurality of PTFE fibrils, calculated according to the Compositional Analysis Test Method, based on the total weight of the composition.

[0210] Embodiment 37C is the porous substrate of any one of Embodiments 1C-36C, wherein the substrate having the composition disposed thereon comprises at least 1%, at least 5%, at least 15%, at least 25%, at least 45%, at least 55%, at least 65%, or at least 80% by weight of PTFE fibrils (short-chain PTFE fibrils and long-chain PTFE fibrils combined), calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition. In some embodiments, the composition comprises at most 95%, at most 80%, at most 65%, at most 55%, at most 45%, at most 25%, at most 15%, or at most 5% by weight of PTFE fibrils, calculated according to the Compositional Analysis Test Method, based on the total weight of the substrate-composition.

[0211] Embodiment 38C is an embodiment in which the composition comprises at least 0.1%, at least 1%, at least 5%, at least 15%, at least 25%, at least 45%, at least 55%, at least 65%, or at least 80% by weight of short-chain PTFE fibrils (if present), calculated according to the Compositional Analysis Test Method, based on the total weight of the composition. The composition comprises no more than 95%, no more than 80%, no more than 65%, no more than 55%, no more than 45%, no more than 25%, no more than 15%, no more than 5%, or no more than 1% by weight of short-chain PTFE fibrils (if present), calculated according to the Compositional Analysis Test Method, based on the total weight of the composition.

[0212] Embodiment 39C is the porous substrate of any one of Embodiments 1C-38C, wherein the composition comprises at least 0.01%, at least 1%, at least 5%, at least 10%, at least 15%, at least 20%, at least 30%, or at least 40% by weight of long-chain PTFE fibrils (if present), calculated according to the Compositional Analysis Test Method, based on the total weight of the composition. The composition comprises no more than 50%, no more than 40%, no more than 30%, no more than 20%, no more than 15%, no more than 10%, no more than 5%, or no more than 1% by weight of long-chain PTFE fibrils (if present), calculated according to the Compositional Analysis Test Method, based on the total weight of the composition.

[0213] Embodiment 40C is the porous substrate of any one of Embodiments 1C-39C, wherein the composition comprises 50% or more, 70% or more, 80% or more, or 90% or more by weight of active particles, based on the weight of the composition and / or matrix, according to the Compositional Analysis Test Method. In some embodiments, the weight percent of total active particles in the composition and / or matrix is ​​95% or less, 90% or less, 80% or less, or 70% or less by weight, based on the weight of the composition and / or matrix, according to the Compositional Analysis Test Method. In some embodiments, the weight percent of total active particles in the composition and / or matrix is ​​0% or more, 0.001% or more, 0.01% or more, 0.1% or more, 1% or more, 2% or more, 3% or more, 4% or more, 5% or more, 10% or more, or 15% or more by weight, based on the weight of the composition and / or matrix, according to the Compositional Analysis Test Method. In some embodiments, the total active particle weight percent in the composition and / or matrix is ​​20 wt.% or less, 15 wt.% or less, 10 wt.% or less, 5 wt.% or less, 4 wt.% or less, 3 wt.% or less, 2 wt.% or less, 1 wt.% or less, 0.1 wt.% or less, 0.01 wt.% or less, or 0.001 wt.% or less, based on the weight of the composition and / or matrix, according to the Compositional Analysis Test Method.

[0214] Embodiment 41C is the porous substrate of any one of Embodiments 1C-40C, wherein the substrate having the composition disposed thereon comprises at least 0 wt%, at least 1 wt%, at least 2 wt%, at least 3 wt%, at least 4 wt%, at least 5 wt%, at least 10 wt%, at least 15 wt%, at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 70 wt%, at least 80 wt%, or at least 90 wt% active particles, calculated according to the Compositional Analysis Test Method based on the total weight of the substrate-composition. In some embodiments, the porous substrate having the composition disposed thereon comprises 95% by weight or less, 90% by weight or less, 80% by weight or less, 70% by weight or less, 50% by weight or less, 40% by weight or less, 30% by weight or less, 20% by weight or less, 15% by weight or less, 10% by weight or less, 5% by weight or less, 4% by weight or less, 3% by weight or less, 2% by weight or less, or 1% by weight or less of active particles, based on the total weight of the substrate-composition, calculated according to the Compositional Analysis Test Method.

[0215] Method Embodiments Embodiment 1M is a method of disposing a composition on a porous substrate to obtain the porous substrate of any one of Embodiments 1C-30C; The composition comprises: a matrix comprising a plurality of PTFE fibrils formed from a PTFE resin; and a plurality of active particles; The above method is i) optionally aerating the emulsion to form an aerated emulsion, wherein the emulsion and the aerated emulsion comprise a PTFE resin, a surfactant, and a dispersing agent; ii) optionally, adding a solid particulate composition to the aerated emulsion to form a matrix premix, wherein the solid particulate composition comprises solid particulates, and the matrix premix comprises a PTFE resin, a surfactant, a dispersant, and the solid particulate composition; iii) optionally aerating the matrix premix to form an aerated matrix premix, wherein the aerated matrix premix comprises a matrix premix; iv) contacting at least a portion of the porous substrate with the matrix premix or the aerated matrix premix; v) disposing the hydrated composition on a porous substrate, wherein the hydrated composition comprises a matrix, at least a portion of a dispersant, and at least a portion of a surfactant, and the plurality of active particles comprises at least a portion of solid particulates; and vi) drying the hydrated composition to form a porous substrate having the composition disposed thereon. Includes.

[0216] Embodiment 2M is a method of disposing a composition on a porous substrate to obtain the porous substrate of any one of Embodiments 1C-30C; The composition comprises: a matrix comprising a plurality of PTFE fibrils formed from a PTFE resin; and a plurality of active particles; The above method is i) optionally forming a matrix premix, said matrix premix comprising a PTFE resin, a surfactant, and a dispersant; ii) optionally aerating the matrix premix to form an aerated matrix premix, wherein the aerated matrix premix comprises the matrix premix; iii) contacting at least a portion of the porous substrate with the matrix premix or the aerated matrix premix; iv) contacting at least a portion of the substrate with a solid particulate composition, wherein the solid particulate composition comprises solid particulates; v) disposing the hydrated composition on at least a portion of the porous substrate, wherein the hydrated composition comprises a matrix, at least a portion of a dispersant, and at least a portion of a surfactant, and the plurality of active particles comprises at least a portion of solid particulates; and vi) drying the hydrated composition to form a porous substrate having the composition disposed thereon. Includes.

[0217] Embodiment 3M is the method of embodiment 1M or 2M, wherein the composition further comprises free active particles, free PTFE particles, or both.

[0218] Embodiment 4Ma is the method of any one of embodiments M1-3M, wherein the porous substrate comprises a major surface and a plurality of macro / micropores connecting the major surface; a first portion of the composition is disposed on at least a portion of the major surface, and at least a portion of the macro / micropores are impregnated with a second portion of the composition.

[0219] Embodiment 4Mb is the method of embodiment 4Ma, wherein the composition further comprises free active particles; at least a portion of the macro / micropores comprise a first portion of the macro / micropores; the first portion of the macro / micropores are impregnated with a first component of the composition, and a second portion of the macro / micropores are impregnated with a second component of the composition. In some embodiments, the first component and the second component are at least one particle of the matrix and the free active particles.

[0220] Embodiment 5M is the method of any one of Embodiments M1-4M(a and b), wherein the porous substrate is a wettable porous substrate comprising a plurality of collapsible pores, and the third portion of the composition is embedded within the porous substrate.

[0221] Embodiment 6M is the method of Embodiment 5M (dependent on Embodiment 3M), in which one or more components of the composition are embedded within a porous substrate. In some embodiments, at least one particle of the free active particles is embedded within the porous substrate, at least one PTFE fibril of the free PTFE fibril is embedded within the substrate, a portion of the matrix is ​​embedded within the substrate, or any combination thereof.

[0222] Embodiment 7M is the method of any one of Embodiments 1M-6M, wherein the plurality of PTFE fibrils, free PTFE fibrils, or both of the matrix comprises short-chain PTFE fibrils, long-chain PTFE fibrils, or both.

[0223] Embodiment 8M is the method of Embodiment 7M (dependent on 3M), wherein the free PTFE fibrils comprise long-chain PTFE fibrils, short-chain PTFE fibrils, or both.

[0224] Embodiment 9M is the method of Embodiment 7M (dependent on Embodiment 1M), wherein the PTFE resin of the aerated matrix premix comprises a short-chain PTFE resin and a long-chain PTFE resin.

[0225] Embodiment 10M is the method of embodiment 9M, wherein the PTFE resin of the emulsion, the PTFE resin of the aerated emulsion, the PTFE resin of the concentrated matrix premix, and the PTFE resin of the matrix premix comprise a short-chain PTFE resin.

[0226] Embodiment 11M is the method of embodiment 10M, further comprising adding a long-chain PTFE resin to the emulsion, such that the PTFE resin of the emulsion, the PTFE resin of the aerated emulsion, and the PTFE resin of the matrix premix further comprise a long-chain PTFE resin.

[0227] Embodiment 12M is the method of embodiment 10M, further comprising adding a long-chain PTFE resin to the matrix premix such that the PTFE resin of the matrix premix further comprises a long-chain PTFE resin.

[0228] Embodiment 13M is the method of Embodiment 7M (dependent on Embodiment 2M), wherein the PTFE resin of the matrix premix or aerated matrix premix comprises a short-chain PTFE resin and a long-chain PTFE resin.

[0229] Embodiment 14M is the method of embodiment 13M, wherein the plurality of PTFE resins of the matrix premix, the plurality of PTFE resins of the aerated matrix premix, or both, comprises a short-chain PTFE resin.

[0230] Embodiment 15M is the method of embodiment 14M, further comprising adding a long-chain PTFE resin to the matrix premix or the aerated matrix premix, such that the PTFE resin of the matrix premix and / or the aerated matrix premix further comprises short-chain PTFE.

[0231] Embodiment 16M is the method of any one of Embodiments 1M-15M, wherein the aerated matrix premix and / or matrix premix comprises 0.01% or more, 15% or more, 25% or more, 45% or more, 55% or more, or 65% or more by weight of PTFE resin, based on the total weight of the aerated matrix premix or matrix premix. The aerated matrix premix and / or matrix premix comprises 80% or less, 65% or less, 55% or less, 45% or less, 25% or less, or 15% or less by weight of PTFE resin, based on the total weight of the aerated matrix premix or matrix premix.

[0232] Embodiment 17M is the method of any one of Embodiments 1M-16M, wherein the aerated matrix premix and / or matrix premix comprises 0.01 wt. % or more, 1 wt. % or more, 5 wt. % or more, or 10 wt. % or more of a long-chain PTFE resin, based on the total weight of the aerated matrix premix or matrix premix. The aerated matrix premix and / or matrix premix comprises 15 wt. % or less, 10 wt. % or less, 5 wt. % or less, or 1 wt. % or less of a long-chain PTFE resin, based on the total weight of the aerated matrix premix or matrix premix.

[0233] Embodiment 18M is the method of any one of Embodiments 1M-17M, wherein the aerated matrix premix and / or matrix premix contains 0.1 wt.% or more, 5 wt.% or more, 15 wt.% or more, 25 wt.% or more, 45 wt.% or more, or 55 wt.% or more short-chain PTFE, based on the total weight of the aerated matrix premix or matrix premix. The aerated matrix premix and / or matrix premix contains 80 wt.% or less, 55 wt.% or less, 45 wt.% or less, 25 wt.% or less, 15 wt.% or less, or 5 wt.% or less short-chain PTFE resin, based on the total weight of the aerated matrix premix or matrix premix.

[0234] Embodiment 19M is the method of any one of Embodiments 1M through 18M, wherein the solid particulate composition comprises 100% solid particulates by weight.

[0235] Embodiment 20M is the method of any one of Embodiments 1M through 19M, wherein the solid particulate composition further comprises a liquid carrier. In some embodiments where the porous substrate is a wettable porous substrate, the liquid carrier comprises a wetting liquid. In some embodiments, the liquid carrier comprises water, one or more organic solvents (e.g., ethyl acetate, ethanol, methanol, isopropanol, butanol, dichloromethane, toluene, acetonitrile, acetone, diethyl ether, amyl alcohol, and tetrahydrofuran), or both.

[0236] Embodiment 21M is the method of embodiment 20M, wherein the solid particulate composition comprises 0.5% by weight or more, 10% by weight or more, 30% by weight or more, or 50% by weight or more solid particulates, based on the total weight of the solid particulate composition. The solid particulate composition comprises 90% by weight or less, 50% by weight or less, 30% by weight or less, or 10% by weight or less solid particulates, based on the total weight of the solid particulate composition.

[0237] Embodiment 22M is the method of any one of Embodiments 2M-7M (dependent on 2M) or 13M-21M (dependent on 2M), wherein the solid particulate composition comprises a first solid particulate, and the matrix premix or aerated matrix premix further comprises a second solid particulate. In such embodiments, the plurality of active particles, the free active particles (if present), or both comprise at least a portion of the second solid particulate.

[0238] Embodiment 23M is the method of embodiment 22M, wherein the matrix premix or aerated matrix premix comprises 0.5% or more, 10% or more, or 30% or more by weight of the second solid particulate, based on the total weight of the matrix premix or aerated matrix premix. The matrix premix or aerated matrix premix comprises 50% or less, 30% or less, or 10% or less by weight of the second solid particulate, based on the total weight of the matrix premix or aerated matrix premix.

[0239] Embodiment 24M is the method of any one of Embodiments 2M through 7M (dependent on 2M) or 13M through 23M (dependent on 2M), wherein the solid particulate composition comprises a first solid particulate composition; and further comprising contacting at least a portion of the substrate with a second solid particulate composition. In some embodiments, the first solid particulate composition and the second solid particulate composition can be the same. In other embodiments, the first solid particulate composition and the second solid particulate composition can be different (e.g., different solid particulates, different liquid carriers, if present, different weight percent solid particulates, or any combination thereof).

[0240] Embodiment 25M is the method of any one of Embodiments 1M-12M (dependent on Embodiment 1M) or 16M-21 (dependent on Embodiment 1M), wherein disposing the hydrated composition on the porous substrate further comprises mixing the matrix premix or aerated matrix premix while in contact with at least a portion of the substrate, and wherein such hydrated composition is disposed on at least a portion of the substrate.

[0241] Embodiment 26M is the method of any one of embodiments 1M through 25M, further comprising contacting at least a portion of the porous substrate with a wetting fluid that is free of solid particulates. In some embodiments, the wetting fluid comprises one or more organic solvents (e.g., ethyl acetate, ethanol, methanol, isopropanol, butanol, dichloromethane, toluene, acetonitrile, acetone, diethyl ether, amyl alcohol, and tetrahydrofuran).

[0242] Embodiment 27M is the method of Embodiment 26M (dependent on Embodiment 2M), wherein after contacting at least a portion of the porous substrate with the matrix premix or the aerated matrix premix, and after contacting at least a portion of the substrate with the solid particulate composition, at least a portion of the porous substrate is contacted with a wetting liquid.

[0243] Embodiment 28M is the method of any one of embodiments 1M to 27M, wherein drying the hydrated composition further comprises contacting at least a portion of the hydrated composition with an absorbent material to remove at least a portion of the dispersing agent, at least a portion of the liquid carrier (if present), at least a portion of the surfactant, or a combination thereof.

[0244] Embodiment 29M is the method of embodiment 28M, wherein the hydrated composition is in contact with the absorbent material for at least 10 seconds, at least 1 minute, or at least 1 hour. The hydrated composition is in contact with the absorbent material for not more than 24 hours, not more than 1 hour, or not more than 1 minute.

[0245] Embodiment 30M is the method of embodiment 28M or 29M, further comprising the steps of removing at least a portion of the absorbent material that is in contact with the hydrated composition; and repeating the steps of contacting the hydrated composition with the absorbent material and removing at least a portion of the absorbent material that is in contact with the hydrated composition multiple times, each time using an absorbent material that was not previously in contact with the hydrated composition.

[0246] Embodiment 31M is the method of any one of embodiments 28M to 30M, wherein the absorbent material comprises cotton; cellulose; a sponge comprising polyester, polyurethane, vegetable cellulose, melamine, or a combination thereof; anhydrous calcium chloride; anhydrous magnesium sulfate; sodium polyacrylate; or a combination thereof.

[0247] Embodiment 32M is the method of any one of embodiments 1M to 31M, wherein drying the hydrated composition further comprises exposing the hydrated composition to an elevated temperature, applying a vacuum to the hydrated composition, or both.

[0248] Embodiment 33M is the method of embodiment 32M, wherein drying the hydrated composition further comprises exposing the hydrated composition to a temperature of from 100°C to 400°C, preferably from 100°C to 300°C, for from 0.1 hours to 24 hours, preferably from 1 hour to 5 hours.

[0249] Embodiment 34M is the method of any one of Embodiments 1M through 33M, wherein the aerated matrix premix and / or matrix premix comprises 0.5% by weight or more, 5% by weight or more, or 20% by weight or more surfactant, based on the total weight of the aerated matrix premix or matrix premix. The aerated matrix premix and / or matrix premix comprises 40% by weight or less, 20% by weight or less, or 5% by weight or less surfactant, based on the total weight of the aerated matrix premix or matrix premix.

[0250] Embodiment 35M is the method of any one of Embodiments 1M through 34M, wherein the surfactant comprises a non-ionic non-fluorinated surfactant.

[0251] Embodiment 36M is the method of embodiment 35M wherein the surfactant comprises polyethylene glycol trimethylnonyl ether.

[0252] Embodiment 37M is the method of any one of Embodiments 1M through 36M, resulting in a total active particle loading capacity of 50 wt.% or greater, 70 wt.% or greater, 80 wt.% or greater, or 90 wt.% or greater based on a compositional test method (i.e., a loading capacity test method). The disclosed method results in a total active particle loading capacity of 95 wt.% or less, 90 wt.% or less, 80 wt.% or less, or 70 wt.% or less based on a compositional test method (i.e., a loading capacity test method).

[0253] Example These examples are for illustrative purposes only and should not be construed as unduly limiting the scope of the appended claims. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present disclosure are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should, at the very least, be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0254] Unless otherwise noted, all parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight, and all reagents used in the examples were obtained or are available from common chemical suppliers such as, for example, Sigma-Aldrich Company (St. Louis, Missouri); Carus (Peru, Illinois); Calgon Carbon (Moon Township, Pennsylvania); Ultramet (Los Angeles, California), or can be synthesized by conventional methods.

[0255] The following abbreviations may be used in the following examples and / or elsewhere in this disclosure: Mn = number average molecular weight; ppm = parts per million; ppb = parts per billion; mL = milliliters; L = liter; LPM = liters per minute; m = meter, mm = millimeter, min = minute; s = second; cm = centimeter, μm = micrometer, kg = kilogram, g = gram, min = minute, s = second, h = hour, °C = degrees Celsius, °F = degrees Fahrenheit; wt% = weight percent; M = moles; μM = micromoles; mM = millimoles; and DI Water = deionized water.

[0256] Table 1 is a Bill of Materials that provides a list of components used in the examples, as well as their associated vendor sources, abbreviations, and Chemical Abstracts Service (CAS) numbers. [Table 1]

[0257] Test Method: Dimensional Analysis Dimensional and topographical analyses of the various compositions and substrates of the examples were performed by scanning electron microscopy (SEM) using a JSM-7100F microscope. Prior to imaging, the samples were sputter-coated with gold / palladium for 120 seconds to prevent static buildup. Measurements were then performed using ImageJ software to calculate the average length of long-chain PTFE fibrils, the average resin particle size of long-chain PTFE resins, the average length of short-chain PTFE fibrils, the average resin particle size of short-chain PTFE resins, the average diameter of short-chain PTFE fibrils, the average diameter of long-chain PTFE fibrils, the average particle size of multiple active particles, the average particle size of free active particles, and the average porosity. Ten repeated measurements of length, width, diameter, and particle size were performed, and the average values ​​of the various parameters were calculated.

[0258] Acid gas breakthrough The coated polyurethane foam was subjected to HS adsorption as a proof of concept. The foam was laminated with 25% surface openness on the inlet side (left inlet) and 25% openness on the outlet side (right outlet), creating an S-shaped flow profile and maximizing fluid residence time. HS breakthrough performance was evaluated at 25 ppm and an initial flow rate of 100 cm. 3 / min, followed by 300cm after 1200 min 3 The sample was saturated until it reached 32% (8 ppm) of the initial H2S concentration, which took approximately 6000 minutes.

[0259] Composition analysis The amount of each component in the matrix / composition and composition-substrate composite is calculated according to the following compositional analysis test method, which is sometimes called the loading capacity test method.

[0260] The solids loading capacity of the composition material was calculated from the incipient wetness formulation, assuming homogeneous mixing of the solids and complete removal of the water / surfactant mixture. As an example, a matrix and / or composition was formed from 13.3 g of CARULITE, 5 g of PTFE-E, and 3 g of PTFE-12 (total weight 21.3 g). The PTFE-E material was known to be composed of 60% PTFE solids by weight, as detailed by the manufacturer, and the resulting weight of PTFE solids was calculated as the product of the weight fraction of PTFE solids and the weight used (e.g., if 5 g of PTFE-E was used, 60% PTFE固形分 x5g エマルション =3g PTFE固形分 The solids content of each component was then calculated on a dry component basis; i.e., the calculation did not take into account the contribution of the water or surfactant components, using the following formula:

number

number

[0261] Thus, the composition or matrix contained a total of 62.5% by weight of active particles (CARULITE). The composition or matrix also contained 18.6% by weight of short-chain PTFE fibrils and 18.6% by weight of long-chain PTFE fibrils. Stated another way, the composition or matrix contained 62.5% by weight of active particles and 37.2% by weight of PTFE fibrils.

[0262] For the substrate on which the composition is placed, the mass of the substrate and the mass of the matrix / composition placed on the substrate can also be considered. For example, if 0.5 g of the composition is placed on 0.5 g of substrate (the difference in the mass of the substrate before and after the composition is placed is 0.5 g), the amount of each component of the substrate-composition composite will be 50% of the composite itself. For example, the substrate-composition will be 50 wt% substrate; 31.25 wt% active particles; 9.3 wt% short-chain PTFE fibrils; and 9.3 wt% long-chain PTFE fibrils.

[0263] Example 1: Disposition of a composition onto a porous substrate using a first method The first method was used to deposit a composition onto a porous substrate, PU-15 foam. This composition included PTFE-E, PTFE-12, CSAC, and K2CO3. This method involved forming an aerated emulsion containing 5 g of PTFE-E resin and 3 g of PTFE-12 resin in 20 ml of DI water. Aeration was achieved by vigorously shaking the emulsion by hand to induce foaming, suspending the PTFE-12 resin. Next, 13.3 g of CSAC and a solution of 20 g of K2CO3 in 20 mL of DI water (solid particulate composition) were added to the aerated emulsion to create a matrix premix. The water / K2CO3 solution was added after the CSAC addition to prevent destabilization of the PTFE surfactant. Next, a 3-inch (7.62 cm) x 3-inch (7.62 cm) PU-15 foam was submerged in the matrix premix, after which the liquid was allowed to absorb into the polymer structure. The sample was then removed from the matrix premix and dried under vacuum for 24 hours to force the KCO to precipitate. The foam weighed 1.8051 g before the composition was applied. The foam weighed 16.2170 g after the composition was applied. Nearly 10-fold loading was achieved by this method. The foam was then characterized by SEM, as shown in Figures 13 and 14. SEM images revealed that the composition contained matrix and free active particles. The matrix was primarily allocated to the PU-15 surface (Figure 13A), as evidenced by the particles being fibrillated and interconnected around the polymer layer (Figure 13B).

[0264] However, cross-sectional imaging of PU-15 (Figure 14) revealed that some of the active particles (i.e., free active particles) were absorbed into the polymer structure framework. Specifically, as shown in Figure 14B, small particles were present parallel to the PU-15 polymer grains, indicating the growth of precipitates inside the polymer walls (i.e., free active particles embedded within the solid portion of the porous polymer matrix). This phenomenon may be due to the fact that PU-15 is a wettable substrate. As the wetting fluid (in this case, a water / surfactant mixture) swelled the substrate and formed micropores, a variable amount of dissolved K2CO3 may have migrated into the micropores of the structure along with the wetting fluid.

[0265] The PU-15 substrates with the composition were evaluated for H2S adsorption to demonstrate the adsorption capabilities of the material as a proof-of-concept. An acid gas breakthrough test method was used. Briefly, the substrates were cut into 1-inch (2.54 cm) x 1-inch (2.54 cm) shapes and packaged to maximize residence time, creating a z-shaped flow path throughout the structure. More specifically, the PU-15 substrates were laminated with plastic, leaving the bottom left 0.25 inches (0.635 cm) and top right 0.25 inches (0.635 cm) of the package open, creating a z-shaped profile. H2S breakthrough performance was measured at 25 ppm with an initial flow rate of 100 cm3, as shown in Figure 15. 3 / min, 300cm after 1200 min 3 / min. The H2S adsorption capacity of this substrate was found to be approximately 20 mg / g, which is comparable to the expected value for the K2CO3 loading. The pressure drop of the material was also small enough to not be detected in the test system, although this may be a by-product of the small sample size.

[0266] Example 2: Disposition of a composition onto a porous substrate using a second method A second method was used to deposit a composition onto a PU-15 porous substrate, which included PTFE-E, PTFE-12, CSAC, and K2CO3.

[0267] Solid particulate compositions were prepared as follows: CSAC was first impregnated with various amounts of K2CO3 (1:1, 2.5:1, 5:1, 10:1 K2CO3:CSAC) in 30 mL of DI water. 5 g of the impregnated CSAC was added to 30 mL of ethanol to prepare the solid particulate compositions. Ethanol was chosen as the liquid carrier for the solid particulate compositions because K2CO3 cannot be redissolved in alcohol.

[0268] A concentrated emulsion (e.g., concentrated matrix premix) was prepared containing 25 g of PTFE-E / 7 g of PTFE-12 in water. The concentrated emulsion was diluted with 20 mL of DI water to form the matrix premix. No aeration was performed.

[0269] PU-15 pieces (1 inch x 1 inch; 2.54 cm x 2.54 cm) were immersed in the matrix premix for 30 seconds on each side, followed by a bath of the solid particulate composition, and then a bath of ethanol. The pieces were then dried overnight under vacuum at ambient temperature to extract the remaining water, ethanol, and surfactant and to force the precipitation of dissolved KCO from the residual water in the matrix premix. As shown in Figure 16, coating PU-15 via this second method (16B) was observed to result in less blockage of PU-15 pores than the method described in Example 1 (16A).

[0270] Example 3: Disposition of Composition onto Porous Substrate Using Methods 3 and 4 Example 3 compares a third and fourth method for disposing a composition on a PU-15 substrate. Both methods involve exposing the substrate to a solid particulate composition containing KCO dissolved in water. The fourth method further involved exposing the substrate to an ethanol bath (wetting composition). This example also compares the properties of a porous substrate having a composition containing both PTFE-E and PTFE-12 disposed thereon with a porous substrate having a composition containing only PTFE-E disposed thereon.

[0271] Table 2 shows the components of each composition placed on each substrate, and whether the substrate was exposed to an ethanol bath (Method 4) or not (Method 3). [Table 2]

[0272] Methods 3 and 4 both involved aerating a PTFE-E emulsion and diluting it with 60 g of DI water to form an aerated emulsion. PTFE-12 (for Substrate 2 and Substrate 3) was added to the aerated emulsion and mixed until no visible PTFE-12 resin was present. Activated carbon was added to the aerated emulsion and subsequently mixed by stirring for 2 minutes to form a matrix premix. A polyurethane foam substrate was immersed in each matrix premix for 60 seconds. The substrate was then transferred to a bath containing K2CO3 dissolved in water (e.g., a solid particulate composition). This process initiated a phase change and resulted in visible coagulation of the PTFE / carbon / base. After the samples were immersed in the K2CO3 solution for 60 seconds, Substrate 1 and Substrate 3 were transferred to a bath containing 200 mL of ethanol, and the coagulated carbon / PTFE layer was immersed into the structural framework of the polyurethane sample.

[0273] All substrate samples were dried under vacuum (P = 0 bar) at 130 °C for 24 hours to remove ethanol, water, and surfactant. Electron microscopy was used to compare Substrate 1 and Substrate 2. The topography of Substrate 2, as shown in Figure 17A, showed that the coating was primarily distributed on the surface, with no clear or obvious nucleation (e.g., embedding) of K2CO3 in the polyurethane framework. In contrast, microscopic observation of Substrate 1 (Figure 17B) showed that immersion of the substrate in ethanol after the K2CO3 / DI bath resulted in the migration of K2CO3 ions to the polyurethane framework. The subsequent vacuum drying process resulted in the supersaturation of these ions, which ultimately precipitated in the polyurethane in the form of nucleated (e.g., embedded) K2CO3 particles (e.g., free active particles). It should be noted that the use of ethanol as a wetting agent is important because i) polyurethane is alcohol wettable and ii) K2CO3 is insoluble in ethanol, making the migration of K2CO3 from the initial coating layer into the ethanol bath less favorable than migration of the K2CO3 from the solid phase into the polyurethane. Without wishing to be bound by theory, it is believed that the residual water in the surface coating acts as a carrier phase for the K2CO3 to migrate from the surface into the polyurethane, and the ethanol bath acts as a means for the polyurethane chains to open up and become wettable to the mixture (e.g., forming micropores).

[0274] Regarding the role of PTFE-E and PTFE-12, the topographies of Substrate 1 and Substrate 3 were evaluated by electron microscopy, as shown in Figure 18. Figures 18A and 18B show macroscopic cracks likely caused by swelling due to ethanol wetting. Furthermore, Substrate 3 was observed to be mechanically unstable because the network polymer turned into powder when pressure was applied. In comparison, Figures 18C and 18D show that the inclusion of PTFE-12 in Substrate 3 resulted in a surface free of macroscopic cracks. While not wishing to be bound by theory, based on Figure 18D, it is believed that the PTFE-12 chains filled the macroscopic cracks caused by ethanol wetting, suggesting that long-chain PTFE fibrils enable self-healing of the polyurethane backbone. In contrast, the PTFE introduced by PTFE-E may enable particle attachment, as shown in other examples.

Claims

1. a porous substrate comprising a composition disposed thereon; The composition comprises a matrix, the matrix comprising: a plurality of PTFE fibrils; and Multiple active particles A porous substrate comprising:

2. 10. The porous substrate of claim 1, wherein the plurality of PTFE fibrils comprises short-chain PTFE fibrils and long-chain PTFE fibrils.

3. 3. The porous substrate of claim 1 or 2, wherein the composition further comprises free active particles, free PTFE fibrils, or both.

4. 4. The porous substrate of claim 1, wherein the porous substrate comprises a major surface and a plurality of macropores connected to the major surface; a first portion of the composition is disposed on at least a portion of the major surface; and at least a portion of the plurality of macropores is impregnated with a second portion of the composition.

5. 5. The porous substrate of claim 4 when dependent on claim 3, wherein a portion of the plurality of macropores comprises a first portion of macropores; the first portion of macropores is impregnated with a first component of the composition; and a second portion of macropores is impregnated with a second component of the composition.

6. The porous substrate of claim 5 , wherein the first component comprises the matrix and the second component comprises at least one particle of the free active particles.

7. 7. The porous substrate of claim 1, further comprising a third portion of the composition embedded within the porous substrate.

8. 8. The porous substrate of claim 7, wherein the porous substrate comprises at least one free PTFE fibril of the free PTFE fibrils, at least one free active particle of the free active particles, at least a portion of the matrix, or any combination thereof, embedded within the porous substrate.

9. 9. The porous substrate of any one of claims 1 to 8, wherein the plurality of particles, the free active particles, if present, or both comprise a catalyst, an adsorbent, a growth seed, a metal-organic framework (MOF), a bioactive material, an electroactive material, or any combination thereof.

10. 9. The porous substrate of any one of claims 1 to 8, wherein the porous substrate is made from a material comprising: reticulated polyurethane without heat treatment; reticulated silicon carbide, reticulated metal, reticulated alumina, reticulated cellulose; reticulated melamine; reticulated activated carbon; or any combination thereof.

11. 11. The porous substrate of any one of claims 2 to 10 dependent on claim 2, wherein the free PTFE fibrils comprise long-chain PTFE fibrils.

12. 1. A method of disposing a composition on a porous substrate, comprising: The composition comprises: a matrix comprising a plurality of PTFE fibrils formed from a PTFE resin; and a plurality of active particles; The method comprises: i) optionally aerating the emulsion to form an aerated emulsion, said emulsion and said aerated emulsion comprising: PTFE resin; surfactants; and Dispersants a process comprising: ii) optionally adding a solid particulate composition to the aerated emulsion to form a matrix premix, the solid particulate composition comprising solid particulates, the matrix premix comprising: the PTFE resin; the surfactant; the dispersant; and The solid fine particle composition a process comprising: iii) optionally aerating the matrix premix to form an aerated matrix premix; wherein the aerated matrix premix comprises the matrix premix; iv) contacting at least a portion of a porous substrate with said matrix premix or said aerated matrix premix; v) disposing the hydrated composition onto the porous substrate, the hydrated composition comprising: the matrix; at least a portion of the dispersant; and At least a portion of the surfactant Including, the plurality of active particles comprising at least a portion of the solid particulates; and vi) drying the hydrated composition to form the porous substrate having the composition disposed thereon. A method of disposing a composition on a porous substrate, comprising:

13. 1. A method of disposing a composition on a porous substrate, comprising: The composition comprises: a matrix comprising a plurality of PTFE fibrils formed from a PTFE resin; and a plurality of active particles; The method comprises: i) optionally forming a matrix premix, said matrix premix comprising: PTFE resin; and surfactants a process comprising: ii) optionally aerating the matrix premix to form an aerated matrix premix, wherein the aerated matrix premix comprises the matrix premix; iii) contacting at least a portion of the porous substrate with the matrix premix or the aerated matrix premix; iv) contacting at least a portion of said substrate with a solid particulate composition, said solid particulate composition comprising solid particulates; v) disposing the hydrated composition onto at least a portion of the porous substrate; the hydrated composition comprising: the matrix; at least a portion of the dispersant; and At least a portion of the surfactant Including, the plurality of active particles comprising at least a portion of the solid particulates; and vi) drying the hydrated composition to form the porous substrate having the composition disposed thereon. A method of disposing a composition on a porous substrate, comprising:

14. 13. The method of claim 11 or 12, wherein the hydrated composition is dried to obtain the porous substrate of any one of claims 1 to 11.

15. 15. The method of any one of claims 11 to 14, wherein the solid particulate composition further comprises a liquid carrier.

16. the solid particulate composition comprises a first solid particulate composition; 16. The method of any one of claims 12 to 15 when dependent on claim 12, further comprising contacting at least a portion of the substrate with a second solid particulate composition.

17. the solid particulate composition comprises a first solid particulate; the matrix premix or aerated matrix premix further comprises a second solid particulate; and 17. The method of any one of claims 12 to 16 when dependent on claim 12, wherein at least a portion of the plurality of active particles, the free active particles, if present, or both, comprise at least a portion of the second solid particulate.

18. 18. The method of claim 17, wherein the aerated matrix premix or the matrix premix comprises 0.5 wt. % to 50 wt. % of the second solid particulate, based on the weight of the aerated matrix premix or the weight of the matrix premix.

19. 19. The method of any one of claims 11 to 18, wherein drying the hydrated composition to form the porous substrate having the composition disposed thereon further comprises contacting at least a portion of the hydrated composition with an absorbent material to remove at least a portion of the dispersing agent, if present, at least a portion of the liquid carrier, at least a portion of the surfactant, or a combination thereof.

20. 19. The method of any one of claims 11 to 18, wherein drying the hydrated composition to form the porous substrate having the composition disposed thereon further comprises exposing the hydrated composition to an elevated temperature, applying a vacuum to the hydrated composition, or both.

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