SOLID-RESISTANT POLYMER COMPOSITE ARTICLES AND METHODS OF FORMING THEM

Abstract

A solid-retained polymer composite article is disclosed. The polymer composite article includes a composite region having a first porous polymer including a plurality of pores and a retained solid. The composite region has at least a portion of the retained solid immobilized within some of the pores. In embodiments where the retained solid is a solid sorbent material, the article is configured to receive carbon dioxide through the first porous polymer capable of adsorbing to the solid sorbent.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 157,442, filed March 5, 2021, and U.S. Provisional Application No. 63 / 302,857, filed January 25, 2022, the disclosures of each of which are incorporated herein by reference in their entirety.

[0002] Field The present disclosure relates to solid-retained polymer composite articles, methods of forming polymer composite articles by entrainment, and methods of using the polymer composite articles. In embodiments where the retained solid is a solid adsorbent material, the articles may be used for adsorption purposes, including adsorption for direct air capture (DAC) of carbon dioxide. [Background technology]

[0003] background Rising carbon dioxide (CO2) levels due to greenhouse gas emissions have been shown to be harmful to the environment. As reported in the Climate.gov article “Climate Change: Atmospheric Carbon Dioxide,” the average atmospheric carbon dioxide level in 2019 was 409.8 ppm, the highest level recorded in the past 800,000 years. The rate at which atmospheric CO2 is increasing is also much higher than in previous decades.

[0004] To mitigate the effects of climate change, it is necessary not only to reduce CO2 emissions to zero but to make them negative in the near future. Several possibilities exist to achieve negative emissions, such as the combustion of biomaterials to generate electricity, combined with CO2 capture from combustion flue gases and subsequent CO2 sequestration ("BECCS") or direct air capture of CO2 ("DAC").

[0005] Gas separation by adsorption has many different applications in industry, such as the removal of specific components from gas streams, where the desired product can be either the component removed from the gas stream, the remaining depleted stream, or both. This allows both minor and major components of the gas stream to be subjected to the adsorption process. One important gas separation application is in the recovery of CO2 from gas streams such as flue gas, exhaust gas, industrial waste gas, biogas, and atmospheric air. Air can be considered a dilute feed stream for CO2.

[0006] Direct capture of CO2 from the atmosphere, known as DAC, is one of several means of mitigating anthropogenic greenhouse gas emissions and has attractive economic prospects as a non-fossil, site-independent source of CO2 for commodity markets and the production of synthetic fuels. Specific advantages of capturing CO2 from the atmosphere include: a) DAC can address the emissions of distributed sources (e.g., land, sea, and air vehicles), which account for a large proportion of global greenhouse gas emissions and which cannot currently be captured at the emission site in an economically viable manner; b) DAC can address conventional emissions and therefore can produce truly negative emissions; and c) DAC systems do not need to be attached to the emission source and are site-independent, meaning they can be installed at the site where the CO2 is further processed or used.

[0007] There is a growing drive to develop and improve these processes to make them more efficient, maximizing the amount of CO2 removed from the atmosphere while minimizing the energy required in the process.

[0008] FIG. 1 is a schematic diagram of the process involved in a conventional DAC system 10. An inlet feed stream 11 containing a mixture of CO2 molecules 16 in a non-CO2 diluent 18 is provided. For example, the inlet feed stream 11 can be an air stream. During the adsorption process, the inlet feed stream 11 is exposed to a sorbent 12. The CO2 molecules 16 adsorb onto the sorbent 12, while the non-CO2 diluent 18 passes through the sorbent 12 and is exhausted from the system 10. The sorbent 12 then undergoes a desorption process to release the CO2 molecules 16 from the sorbent 12. The desorption process can involve moisture in the form of liquid water or water vapor, or a change in system temperature due to a reaction or energy supplied to the system. This desorption process is referred to as "swing" adsorption to define the cyclical process of repeated CO2 adsorption and desorption. If moisture swing adsorption is used, the sorbent 12 can be exposed to moisture in the form of water vapor or liquid water, causing the CO2 molecules 16 to desorb. If temperature swing adsorption is used, heat can be applied to the sorbent 12 to cause desorption of the CO2 molecules 16. These moisture and / or temperature fluctuations can temporarily break the bonds holding the molecules to the sorbent 12, thereby releasing the CO2 molecules 16. The desorbed CO2 molecules 16 can then be separated from the sorbent 12 and collected as product 14. The collected CO2 molecules 16 can then be concentrated and subjected to further necessary processing before being used or stored. It is important that the sorbent 12 used be able to repeatedly withstand the environment required to separate the CO2 molecules 16, e.g., high temperature and humidity conditions.

[0009] Established literature and techniques exist for DAC. One example is the use of an article that includes a substrate, such as a monolith, that supports or is coated with a sorbent material. Alterations are established by varying the type of substrate and the sorbent used. However, these previously established literature and methods are limited in their ability to efficiently cycle between adsorption and desorption states. They also have limitations regarding the durability of the article. Additionally, the article may degrade when exposed to environments with high temperatures or high humidity levels, or a combination thereof, potentially resulting in a shortened lifespan. Summary of the Invention

[0010] Abstract An entrained polymer composite article is disclosed. The entrained polymer composite article includes a porous polymer having a plurality of pores and a composite region having a solid material. The composite region has at least some of the solid material entrained, retained, and immobilized within some of the pores. When the article is entrained with a solid adsorbent material, the article can be configured to receive carbon dioxide through the porous polymer, which can be adsorbed onto the solid sorbent.

[0011] According to one example ("Example A"), a sorbent polymer composite article includes a first region having a solid sorbent and a first porous polymer, the first porous polymer including a plurality of pores, the first region having at least some solid sorbent immobilized within at least some of the pores of the first porous polymer, and the first region configured to receive carbon dioxide through the first porous polymer and adsorb carbon dioxide onto the solid sorbent.

[0012] According to a second example ("Example B"), a method of combining a solid sorbent and a first porous polymer includes providing a first porous polymer having a plurality of pores; providing a solid sorbent; combining the sorbent and the first porous polymer such that at least a portion of the sorbent is disposed within the pores of the first porous polymer; and immobilizing the solid sorbent within the pores of the first porous polymer.

[0013] According to a third example ("Example C"), an entrained polymer composite article includes a first porous polymer including a plurality of nodes, a plurality of fibrils connecting adjacent nodes, and a plurality of pores defined by the nodes and fibrils, the first porous polymer having a first state in which the fibrils are substantially straight and a second state in which the fibrils are substantially wavy or tortuous and the pores are smaller in size than in the first state, and a plurality of solid particles held within the pores in the first state and immobilized within the pores in the second state. [Brief explanation of the drawings]

[0014] BRIEF DESCRIPTION OF THE DRAWINGS [Figure 1] Figure 1 is a schematic diagram of the processes involved in a DAC system.

[0015] [Figure 2] FIG. 2 is an elevational view of a sorbent polymer composite article of the present disclosure.

[0016] [Figure 2A] FIG. 2A is a schematic elevational view of a first composite region of the first composite article of FIG.

[0017] [Figure 2B] 2B is a schematic elevational view of the first composite region of the first composite article of FIG. 2 in a compressed form.

[0018] [Figure 2C]FIG. 2C is a schematic elevational view of the first composite region of the first composite article of FIG. 2B in a further compressed form.

[0019] [Figure 2D] FIG. 2D is an elevational view of the first sorbent polymer composite article of FIG. 2 shown including an edge seal region of the present disclosure.

[0020] [Figure 3] FIG. 3 is a flow chart illustrating a method of forming the sorbent polymer composite article of FIG.

[0021] [Figure 4A] FIG. 4A is an elevational view of a first region of a sorbent polymer composite article prior to the immobilization step.

[0022] [Figure 4B] FIG. 4B is an elevational view of a first region of the sorbent polymer composite article of FIG. 4A after the immobilization step.

[0023] [Figure 5A] FIG. 5A is an elevational view of the first and second regions of the sorbent polymer composite article during the combining process.

[0024] [Figure 5B] FIG. 5B is an elevational view of the sorbent polymer composite article of FIG. 6A during the immobilization process.

[0025] [Figure 6] 6A, 6B and 6C are SEM images of diamond particle-retained polymer composite article samples according to Example 1. FIG.

[0026] [Figure 7] 7A, 7B, and 7C are SEM images of iron oxide particle-retained polymer composite article samples according to Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0027] Detailed Description of the Invention Definitions and Terminology This disclosure is not intended to be interpreted in a limiting sense. For example, the terms used in this application should be read broadly in the context of the meaning that would be ascribed to them by a specialist in the field.

[0028] With respect to the term imprecision, the terms "about" and "approximately" may be used interchangeably to refer to measurements that include the stated measurement and also measurements that are reasonably close to the stated measurement. A measurement that is reasonably close to the stated measurement deviates from the stated measurement by a reasonably small amount, as understood and easily ascertained by one of ordinary skill in the relevant art. Such deviations may result from measurement errors, differences in calibration of measuring and / or manufacturing equipment, human error in reading and / or setting measurements, fine-tuning made to optimize performance and / or structural parameters given differences in measurements associated with other components, specific implementation scenarios, imprecise adjustment and / or manipulation of the object by a human or machine, and the like. If it is determined that the value of such a reasonably small difference would not be easily ascertainable by one of ordinary skill in the relevant art, the terms "about" and "approximately" may be understood to mean plus or minus 10% of the stated value.

[0029] The term "fibril," as used herein, describes an elongated piece of material, such as a polymer, whose length and width differ substantially from one another. For example, a fibril can resemble a string or piece of fiber, whose width (or thickness) is much shorter or less than its length.

[0030] The term "node," as used herein, describes a connection point of at least two fibrils, which may be defined as a location where two fibrils contact each other, either permanently or temporarily. In some instances, a node may also be used to describe a larger volume of polymer than a fibril and where a fibril begins or ends without a clear continuation of the same fibril through the node. In some instances, a node is wider but shorter than a fibril.

[0031] As used herein, "node" and "fibril" are usually, but not necessarily, connected or interconnected and may be used to describe objects having, for example, microscopic size. A "microscopic" object may be defined as an object having at least one dimension (width, length, or height) so substantially small that the object or details of the object are not visible to the naked eye or are difficult, if not impossible, to observe without the aid of a microscope, such as, but not limited to, a scanning electron microscope (SEM), or an appropriate type of magnifying device.

[0032] Description of Various Embodiments The present disclosure relates to solid-loaded polymer composite articles, methods for forming polymer composite articles by entrainment, and methods for using polymer composite articles. In embodiments in which the loaded solid is a solid adsorbent material, the article can be used to adsorb and separate one or more desired substances from a source stream. While the sorbent polymer composite article is described for use in DAC of carbon dioxide from dilute feed streams such as air, it can be used for other adsorption methods and applications. These methods include, but are not limited to, the adsorption of substances from various inputs, including other gaseous feed streams (e.g., combustion exhaust) and liquid feed streams (e.g., seawater). The adsorbed substance is not limited to carbon dioxide. Other adsorbed substances can include, but are not limited to, other gas molecules (e.g., N2, CH4, CO), liquid molecules, solutes, etc. In certain embodiments, the input can be diluted, containing the adsorbed substance on the order of parts per million (ppm). The article can also support other solid materials for other uses, including pharmaceutical and biological uses.

[0033] 2 illustrates a first exemplary polymer composite article, specifically a sorbent polymer composite article 20, that includes a first composite region 28. The first composite region 28 includes a first porous polymer 22 and a retained solid, illustratively comprising a sorbent material 24. The retained solid can also optionally include a carrier 26. Each element of the first composite region 28 is further described below.

[0034] The first porous polymer 22 of the first composite region 28 can be one of expanded polytetrafluoroethylene (ePTFE), expanded (expanded, expanded, stretched, or foamed) polyethylene (ePE), polytetrafluoroethylene (PTFE), or another suitable porous polymer. It will be understood that nonwoven materials, such as nanospun, meltblown, spunbond, and porous cast films, can be various other suitable porous polymer forms. The first porous polymer 22 can be expanded by stretching the polymer at a controlled temperature and a controlled stretching rate, causing the polymer to fibrillate. After expansion, the first porous polymer 22 can include a microstructure of multiple nodes 30 and multiple fibrils 34 connecting adjacent nodes 30. In these examples, the first porous polymer 22 includes pores 32 bounded by the fibrils 34 and nodes 30. Exemplary node and fibril microstructures are described in U.S. Patent No. 3,953,566 to Gore, which is incorporated herein by reference in its entirety. The pores 32 of the first porous polymer 22 can be considered micropores. Such pores can have a single pore size or can have a distribution of pore sizes. The average pore size can range from 0.1 microns to 100 microns in certain embodiments.

[0035] The sorbent material 24 of the first complex region 28 is a substrate having a surface configured to retain desired substances from the input as a thin film on the surface by adsorption. The sorbent material 24 varies based on which substances are targeted for adsorption. In various embodiments, the sorbent material 24 is a carbon dioxide sorbent material, including, but not limited to, an ion exchange resin (e.g., a strong base anion exchange resin such as Dowex® Marathon® A resin, Dow Chemical available from the Company), zeolites, activated carbon, alumina, metal organic frameworks, polyethyleneimine (PEI), or another suitable carbon dioxide adsorbent material, such as desiccants, carbon molecular sieves, carbon adsorbents, graphite, activated alumina, molecular sieves, aluminophosphates, silicoaluminophosphates, zeolite adsorbents, ion exchanged zeolites, hydrophilic zeolites, hydrophobic zeolites, modified zeolites, natural zeolites, faujasite, clinoptilolite, mordenite, metal exchanged silicoaluminophosphates, monopolar resins, bipolar resins, aromatic crosslinked polystyrene matrices, brominated aromatic matrices, methacrylate ester copolymers, graphite based adsorbents, carbon fibers, carbon nanotubes, nanomaterials, metal salt adsorbents, perchlorates, oxalates, alkaline earth metal particles, ETS, CTS, metal oxides, chemisorbents, amines, organometallic reactants, hydrotalcites, silicalites, zeolitic imadazolate frameworks, and Metal organic frameworks (MOFs), adsorbent compounds, and combinations thereof may be mentioned.

[0036] The sorbent material 24, 24' can be present in the first porous polymer 22 as a coating, a filler, entrained particles, and / or in another suitable form, as described further below. In the embodiment shown in FIG. 2, solid particles of the sorbent material 24 on a carrier 26 are entrained in the first porous polymer 22 such that the particles occupy and are retained within the pores 32 between the nodes 30 and fibrils 34 of the first porous polymer 22. It is also within the scope of this disclosure for the first porous polymer 22 to be coated with the sorbent material 24' such that the sorbent material 24' forms a substantially continuous coating on the nodes 30 and / or fibrils 34 of the first porous polymer 22, as shown in FIG. 2D. It is further within the scope of this disclosure for the first porous polymer 22 to be filled with the sorbent material 24 such that the sorbent material 24 is incorporated into the nodes 30 and / or fibrils 34 of the first porous polymer 22.

[0037] The optional carrier 26 in the first composite region 28 is a material configured to increase the surface area of ​​the region it occupies, allowing for increased surface area available for adsorption of the desired substance. The carrier 26 can include mesoporous silica, polystyrene beads, porous polymer beds or spheres, oxide supports, or another suitable carrier material. The carrier 26 can further include a porous film having a porous inorganic material therein, such as calcium sulfate, alumina, activated carbon, or fumed silica. As described above, the carrier 26 can be present within the pores 32 of the first composite region 28 as high-surface-area particles coated or functionalized with the sorbent material 24. The combination of the carrier 26 coated with the sorbent material 24 increases the surface area available for adsorption. In these embodiments, the nodes 30 and fibrils 34 may or may not be coated with the sorbent material 24. The original hydrophobicity of the first porous polymer 22 can be maintained when the nodes 30 and fibrils 34 are uncoated.

[0038] The first composite region 28 of the sorbent polymer composite article 20 includes a first side 72 (e.g., the upper side in FIG. 2 ) and a second side 74 (e.g., the lower side in FIG. 2 ). The sorbent polymer composite article 20 further includes a second region 36 including a second porous polymer 40, the second region 36 being disposed adjacent to the first side 72 of the first composite region 28. In various embodiments, the sorbent polymer composite article also includes a third region 38 including a third porous polymer 48, the third region 38 being disposed adjacent to the second side 74 of the first composite region 28. In this manner, the first composite region 28 can be sandwiched between the second region 36 on the first side 72 and the third region on the second side 74. The second porous polymer 40 of the second region 36 can include a plurality of nodes 42, a plurality of fibrils 46 connecting adjacent nodes 42, and a plurality of pores 44 each formed between each node 42 and fibril 46. Similarly, the third porous polymer 48 of the third region 38 may include a plurality of nodes 50, a plurality of fibrils 52 connecting adjacent nodes 50, and a plurality of pores 54 formed between each node 50 and fibril 52. The pores 44 of the second porous polymer 40 and / or the pores 54 of the third porous polymer 48 may be considered micropores, as further described above.

[0039] The first composite region 28, the second region 36, and the third region 38 of the sorbent polymer composite article 20 may be formed using different processes. In certain embodiments, the first composite region 28, the second region 36, and / or the third region 38 may be formed as separate layers and then bonded together. In this case, the first porous polymer 22 of the first composite region 28, the second porous polymer 40 of the second region 36, and / or the third porous polymer 48 of the third region 38 may be distinct structures. In other embodiments, the first composite region 28, the second region 36, and / or the third region 38 may be formed together and then subjected to different coating processes or surface treatments to distinguish the particular regions, as described further below. In this case, the first porous polymer 22 of the first composite region 28, the second porous polymer 40 of the second region 36, and / or the third porous polymer 48 of the third region 38 may be continuous or monolithic structures.

[0040] The first composite region 28, the second region 36, and the third region 38 of the sorbent polymer composite article 20 can have different degrees of hydrophobicity. The hydrophobicity can be modified by various methods, such as the application of coatings or surface treatments, including, but not limited to, plasma etching and the application of fine topographical features. The first composite region 28 can have a first hydrophobicity, the second region 36 can have a second hydrophobicity, and the third region 38 can have a third hydrophobicity. The first hydrophobicity is less than the second and third hydrophobicities, respectively. The second hydrophobicity can be greater than, less than, or equal to the third hydrophobicity. The greater hydrophobicity of the second and third regions 36, 38 can reduce the permeability of liquid water through the respective regions 36, 38, thus forming a barrier between the surrounding liquid water and the components of the first composite region 28. This reduces degradation of the sorbent material 24, 24' in the first composite region 28 that can be caused by liquid water, improving the life and durability of the sorbent polymer composite article 20. The increased hydrophobicity of the second region 36 and the increased hydrophobicity of the third region 38 relative to the first hydrophobicity of the first composite region 28 can be attributed to the absence of the sorbent material 24, 24' in the second and third regions 36, 38.

[0041] In some embodiments, the first composite region 28 is sealed with a coating (not shown). In particular examples, the coating is configured to be a carbon adsorbent material similar to the sorbent material 24 described above.

[0042] The second porous polymer 40 of the second region 36 and the third porous polymer 48 of the third region 38 can be at least one of polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), expanded polyethylene (ePE), or other suitable porous polymers. The second porous polymer 40 of the second region 36 may be the same or different from the third porous polymer 48 of the third region 38. Furthermore, the first porous polymer 22 of the first composite region 28, the second porous polymer 40 of the second region 36, and the third porous polymer 48 of the third region 38 may be the same or different.

[0043] In various embodiments, the thickness of second region 36 is less than the thickness of first composite region 28, and the thickness of third region 38 is less than the thickness of first composite region 28. The overall thickness of sorbent polymer composite article 20 can be from about 0.1 mm to about 5.0 mm. In certain embodiments, the thickness of first composite region 28 can comprise a majority of the overall thickness, for example, about 70%, about 80%, about 90% or more of the overall thickness.

[0044] The pore characteristics of the porous polymers 22, 40, 48 of the first composite region 28, second region 36, and third region 38, respectively, can be varied. In certain embodiments, the second and third regions 36, 38 can have fewer and / or smaller pores 44, 54 than the first composite region 28 to selectively restrict the permeation of undesirable fluids (e.g., water) into the first composite region 28 while allowing the permeation of desired molecules (e.g., CO) into the first composite region 28. In contrast, the first composite region 28 can have more and / or larger pores 32 than the second and third regions 36, 38 to facilitate the movement of CO through the first composite region 28 for adsorption and desorption.

[0045] Additionally, the pore characteristics can vary between different embodiments, and this variation in pore characteristics can depend on the overall thickness of the sorbent polymer composite article 20, as well as the individual thicknesses of the first composite region 28, the second region 36, and the third region 38.

[0046] FIG. 2A is a schematic elevational view of the first composite region 28 of the sorbent composite article 20 of FIG. 2. In this embodiment, the sorbent polymer composite article 20 (FIG. 2) is relatively thick, e.g., about 3 mm, with the first composite region 28 having a thickness T1 that accounts for a majority of the overall thickness of the sorbent polymer composite 20. The sorbent polymer composite article 20 can be loaded with a desired amount of sorbent material 24 (e.g., about 60% sorbent material 24) to maintain a relatively high porosity, where porosity is the relative ratio of the volume of void space in the first composite region 28 to the overall volume of the first composite region 28. In this manner, the sorbent polymer composite article 20 is structurally relatively open, providing relatively high accessibility to the sorbent material 24. Because of the thickness T1 in this embodiment, the sorbent material 24 remains accessible to gases, although the distance required for gas diffusion may be greater. As a result, the initial rate of gas adsorbing onto the sorbent material 24 may be slower compared to thinner embodiments, as described herein, but equilibrium of CO2 adsorbing onto the sorbent material 24 may be reached more quickly.

[0047] FIG. 2B is an alternative embodiment of the first composite region 28 of FIG. 2A, in which the sorbent composite article 20 (FIG. 2) has a median thickness of, for example, about 0.5 mm. In this embodiment, the first composite region 28 has a thickness T2 that accounts for a majority of the overall thickness of the sorbent polymer composite article 20. In this case, if the amount of polymer 22 (FIG. 2) and the amount of sorbent material 24 in the first composite region are constant compared to the previous embodiment, the porosity is relatively smaller than that of the first composite region 28 of FIG. 2A. Thus, the sorbent polymer composite article 20 maintains a porosity that allows gas access to the sorbent material 24 but is relatively less accessible than the sorbent material 24 of the embodiment of FIG. 2A. As a result, the initial rate of gas adsorption into the sorbent material 24 may be faster due to the shorter diffusion distance, but the time to reach equilibrium CO2 adsorption is increased compared to the embodiment of FIG. 2A.

[0048] FIG. 2C is an alternative embodiment of the first composite region 28 of FIGS. 2A and 2B, in which the sorbent polymer composite article 20 (FIG. 2) is relatively thin, e.g., about 0.1 mm. In this embodiment, the first composite region 28 has a thickness T3 that accounts for a majority of the overall thickness of the sorbent polymer composite article 20. In this case, if the amount of polymer 22 (FIG. 2) and the amount of sorbent material 24 in the first composite region 28 are constant relative to the previous two embodiments, the polymer 22 and available sorbent material 24 are more concentrated within the sorbent polymer composite article 20. The diffusion distance required for gas to pass through the article 20 is shorter due to the compressed thickness of the sorbent polymer composite article 20, but the sorbent material 24 is also less accessible to the gas. As a result, the initial rate of gas adsorption onto the sorbent material 24 is faster than in the previous embodiment, but it may take longer for the system to reach CO2 adsorption equilibrium.

[0049] 2, the pore characteristics of the sorbent polymer composite 20 can vary within each layer, but also across different embodiments as a result of varying various properties including the thickness of the sorbent polymer composite article 20, the thickness of the first composite region 28, the amount of sorbent material 24, and the amount of polymer 22 used in the sorbent polymer composite article 20. In this manner, the relationship between the diffusion length and the accessibility of the sorbent material 24 can be varied to maximize the performance of the sorbent polymer composite article 20.

[0050] The ability to vary the hydrophobicity, thickness, porosity, and other properties of the first composite region 28, the second region 36, and the third region 38 can increase the durability and adaptability of the sorbent polymer composite article 20. For example, increasing the porosity of the second region 36 and the third region 38 can decrease the permeability of fluids to the first region while allowing desired molecules, such as carbon dioxide, to pass through. Additionally, using a relatively thin and flexible sorbent polymer composite article 20 can allow the sorbent polymer composite article 20 to conform to different configurations for carbon dioxide adsorption and desorption.

[0051] In certain instances, the tensile strength of the entire sorbent polymer composite article 20 (first porous polymer 22 including sorbent material 24) is equal to or substantially equal to the strength of the first porous polymer 22 alone (without sorbent material 24). In conventional filling processes, the first porous polymer 22 has strength based on how much filler (in this case, sorbent material 24) is incorporated into the microstructure of the first porous polymer 22. loseIn contrast, in the present disclosure, the first porous polymer 22 is expanded before the sorbent material 24 is introduced, allowing the first porous polymer 22 to be fully formed without weakening the microstructure of the first porous polymer 22. The amount of sorbent material 24 added after expansion can be increased or decreased with little or no effect on the strength of the first porous polymer 22. Thus, the first porous polymer 22 can have a tensile strength after entrainment of the sorbent material 24 that is approximately equal to the original tensile strength of the first porous polymer 22 before the addition of the sorbent material 24. In this manner, the presence of the sorbent material 24 along with the first porous polymer 22 in the sorbent polymer composite article 20 can not reduce the strength of the first porous polymer 22. As a result, the strength of the first porous polymer 22 can be controlled, which in turn allows the strength of the entire sorbent polymer composite article 20 to be controlled, regardless of how much sorbent material 24 is entrained in the sorbent polymer composite article 20. As is known in the art, tensile strength can be measured by stretching the first porous polymer 22 and / or the sorbent polymer composite article 20 and measuring the deformation at different force values.

[0052] The sorptive polymer composite article 20 of FIG. 2 can be used for a variety of adsorption methods. During the adsorption phase, an input feed stream (similar to feed stream 11 of FIG. 1) can be directed across the sorptive polymer composite article 20 to adsorb CO molecules. Then, during the desorption phase, the sorptive polymer composite article 20 can undergo a humidity swing and / or temperature swing process to desorb the CO molecules. As mentioned above, the polymer composite article 20 can also have other applications besides adsorption, where it is more commonly desirable to entrain the first porous polymer 22 with solid particles. These can include pharmaceutical applications, for entraining the porous polymer with a therapeutic agent, or biological applications, for entraining the porous polymer with cells.

[0053] FIG. 2D is an additional elevational view of the sorbent polymer composite article of FIG. 2 , including an additional edge seal region 21. In embodiments, the sorbent polymer composite article 20 includes this edge seal region 21 to protect the components of the sorbent polymer composite article 20. For example, if the sorbent polymer composite article 20 is cut or divided in any manner, such as for production or manufacturing purposes, it may leave the first composite region 28, and thus the sorbent material 24, 24′ within the first composite region 28, exposed to external environmental elements, such as water or steam, which may be detrimental to the properties of the sorbent polymer composite article 20. Therefore, an embodiment with an edge seal region 21 may be desirable. As shown in FIG. 2D , the edge seal region 21 can connect the polymer 40 of the second region 36 and the polymer 48 of the third region 38 and is positioned to cover the exposed polymer 28 of the first composite region on at least one side.

[0054] In the illustrated embodiment of FIG. 2D , the edge seal region 21 is formed by applying an additional layer of sealing material 47 onto the sorbent polymer composite article 20. The sealing material 47 may be the same or different from the material of the second region 36 and the third region 36. For example, the sealing material 47 may be ePTFE (as shown in FIG. 2A ), ePE, a silicone elastomer, or any other suitable non-porous and / or hydrophobic material that protects the first composite region 28. In other embodiments, the edge seal region 21 may be formed by extending the second region 36 and the third region 38 and bonding (e.g., sandwiching, gluing) the regions 36, 38 together. The addition of this edge sealing step benefits the composite by protecting the sorbent retained within the composite and strengthening the leading edge of the composite (the area most susceptible to damage from airborne debris and high-velocity impacts).

[0055] Figure 3 is a flow chart illustrating a method 100 for forming the first composite region 28 of the sorbent polymer composite article 20 of Figure 2. At block 102, the method 100 first involves providing a first porous polymer 22. The first porous polymer 22 can be ePTFE, PTFE, or ePE, as described above, or any other suitable porous polymer.

[0056] At block 104, the method 100 includes providing a solid sorbent material 24 in the form of particles (e.g., a powder), optionally including a carrier 26. The particles of the solid sorbent material 24 can have an average particle size of from about 0.1 μm to about 100 μm, more specifically from about 1 μm to about 10 μm.

[0057] At block 106, the method 100 then includes combining the particles of the solid sorbent material 24 with the first porous polymer 22, with some of the particles of the sorbent material 24 disposed within the pores 32 of the first porous polymer 22. In wet-entrainment embodiments, the combining step involves applying a slurry (not shown) comprising particles of the sorbent material 24 and a liquid carrier (e.g., water) to the first porous polymer 22. deliveryThe first porous polymer 22 can be immersed in the slurry, impregnated with the slurry, and then the liquid carrier can be removed, leaving particles of the sorbent material 24 in the pores 32. This wet entrainment process is similar to a liquid filtration process, and the retained sorbent material 24 of a wet entrainment process is similar to the residue of a filtration process. In a dry entrainment embodiment, the combining step includes applying particles of the solid sorbent material 24 in dry particulate form to the first porous polymer 22 using a forced air flow (e.g., positive or negative pressure, or a combination thereof). After the combining step of block 106, the pores 32 of the first porous polymer 22 can retain the particles of the sorbent material 24. As a result, the pores 32 of the first porous polymer 22 can be filled with particles of the sorbent material 24. The loading amount can vary based on the pore size, particle size, and pressure involved in the process, as well as the time in the process. Advantageously, both the wet and dry entrainment processes of block 106 can preserve the physical and chemical structure of the particles of sorptive material 24. Thus, as noted above, the wet and dry entrainment processes of block 106 can be suitable for use with a variety of solid particles other than the solid particles of sorptive material 24 described herein, including drugs, therapeutic agents, and living cells.

[0058] At block 108, the method 100 further includes immobilizing the particles of the sorbent material 24 within the pores 32 of the expanded first porous polymer 22 of the first composite region 28. In solvent shrinkage embodiments, this immobilization step may include applying a suitable solvent (e.g., isopropyl alcohol (IPA)) to the first porous polymer 22 and sorbent material 24 combination to soak the first porous polymer 22, followed by evaporation of the solvent. This solvent application and subsequent solvent evaporation is configured to shrink the fibrils 34, thereby tightening the pores 32 of the first porous polymer 22 of the first composite region 28 and trapping the particles of the solid sorbent material 24 within the pores 32, as shown and described below with respect to FIGS. 4A and 4B . In heat shrinkage embodiments, the immobilization step may include applying heat to the combination of the solid sorbent material 24 and the first porous polymer 22. The application of heat causes the fibrils 34 to shrink, thereby tightening the pores 32 of the first porous polymer 22 and trapping the particles of the solid sorbent material 24 within the pores 32. This heating step should be performed at a temperature high enough to evaporate the solvent and shrink the fibrils 34, but low enough to avoid damaging the sorbent material 24, for example, from about 60°C to about 200°C. It is within the scope of the present disclosure to perform both the solvent shrinkage process and the heat shrinkage process. The fixation step can reduce the porosity of the first porous polymer 22. After the fixation step in block 108, the pores 32 of the first porous polymer 22 can be tightly filled (e.g., plugged) with particles of the sorbent material 24.

[0059] Further, in various embodiments, the immobilization step can include attaching one or more coating regions 38 onto the first porous polymer 22, such as a second region 36 comprising a second porous polymer 40 and / or a third coating region 38 comprising a third porous polymer 48 (FIG. 2), such that particles of the solid sorbent material 24 are trapped within the pores 32 of the first porous polymer 22. In certain examples, the porous polymers 40, 48 are PTFE, ePTFE, ePE, or other suitable porous polymers as described above. In various embodiments, attaching the second region 36 and / or third region 38 onto the first porous polymer 22 and the solid sorbent material 24 can include laminating the second region 36 and / or third region 38 to the first composite region 28. In various embodiments, the second region 36 and / or third region 38 can be in the form of a polymer sheet. The concept of immobilizing by coating with the second region 36 and / or third region 38 is further described below with respect to FIGS. 5A and 5B.

[0060] 4A is a perspective view of the first composite region 28 of the sorbent polymer composite article 20 prior to immobilization in block 108 (FIG. 3). The first composite region 28 includes a first porous polymer 22 having a plurality of pores 32, a plurality of fibrils 34, and a plurality of nodes 30. In this state, the fibrils 34 are substantially straight. Each of the plurality of pores 32 comprises a pore size 60. The first porous polymer 22 of the first region 28 includes discrete regions of the sorbent material 24 located within the pores 32. Solid particles of the sorbent material 24 and / or carriers 26 are loosely packed within the pores 32 but may not yet be immobilized.

[0061] FIG. 4B is a perspective view of the first composite region 28 of the sorbent polymer composite article 20 of FIG. 4A after the immobilization step of block 108 described with reference to FIG. 3. In this state, the fibrils 34 are bent and / or wavy. Each of the plurality of pores 32 now has a pore size 62 smaller than the pore size 60 referenced in FIG. 4A. This contraction of the fibrils 34 and tightening of the pores 32 serves to immobilize the solid particles of the sorbent material 24 and / or carrier 26 that are tightly packed within the pores 32 of the first porous polymer 22. In certain instances where the solid particles are intended to absorb or adsorb, this process allows the particles to repeatedly expand and contract. The bent or wavy fibrils retain length, allowing for cyclic changes in size or thickness without fibril breakage (tensile failure).

[0062] Another variation of the method 100 of FIG. 3 for forming the sorbent polymer composite article 20 is further described with reference to FIGS. 5A and 5B.

[0063] 5A is a schematic diagram of a portion of the sorbent polymer composite article 20 during the combining step of block 106 (FIG. 3). The sorbent polymer composite article 20 is shown with the third region 38 positioned adjacent the lower second side 74 of the first composite region 28, thereby sealing the lower second side 74 and leaving the upper first side 72 open. The sorbent material 24 may be provided in the form of dry particles and entrained within the forced flow 27 and introduced through the open first side 72 of the first porous polymer 22. The sorbent material 24 may be trapped between the nodes 30 and fibrils 34 of the first porous polymer 22 against the sealed second side 74, thereby retaining the sorbent material 24 within the pores 32 of the first porous polymer 22.

[0064] 5B is a schematic illustration of the sorbent polymer composite article 20 during the immobilization step of block 108 (FIG. 3). In addition to the third region 38 sealing the lower second side 74 of the first composite region 28 similar to FIG. 5A, the sorbent polymer composite 20 further includes a second region 36 sealing the upper first side 72 of the first composite region 28, thereby immobilizing the sorbent material 24 within the polymer 20 of the first composite region 28 between the second region 36 and the third region 38. [Example]

[0065] example Example 1 We first presented an expanded porous polymer sheet of ePTFE fabricated according to the teachings of U.S. Patent No. 5,814,405 to Branca et al. Diamond dust particles ranging in size from 2 to 6 μm were mixed with a 70% IPA / 30% H2O solvent. Using a syringe, the diamond particle / IPA mixture was pulled through the ePTFE sheet. The mixture was then pushed back through the polymer sheet. This process was repeated 10 times. In this case, the particles were injected or entrained into the ePTFE membrane, and during the drying of the solvent, the fibrils contracted to hold / grip the particles, preventing them from migrating. The amount of contraction can be varied based on the membrane's constraint during the drying process.

[0066] Figures 6A, 6B, and 6C are SEM images of porous polymers prepared in this example containing diamond particles approximately 2 μm to 6 μm in size held within the pores of the polymer. Figures 6A-6C are shown with notations indicating the magnification and scale of each SEM image. Figure 6A is at 100x magnification, and the scale indicates a length of 500 μm on the image (so that the distance between two consecutive vertical markers represents 50 μm). The bottom of the image shows the 10.0 kV 5.5 mm x 100 kBSE-COMP 08 / 07 / 2020. Figure 6B is at 1000x magnification, and the scale indicates a length of 50 μm on the image (so that the distance between two consecutive vertical markers represents 5 μm). The bottom of the image shows the 10.0 kV 5.5 mm x 1.00 kBSE-COMP 08 / 07 / 2020. Figure 6C is at 1000x magnification, with a scale indicating 50 μm across the image (the distance between two consecutive vertical markers represents 5 μm). Shown at the bottom of the image is a 10.0 kV 4.8 mm x 1.00 kBSE-COMP 08 / 07 / 2020. Figures 6B and 6C are higher-magnification SEM images of the same sample (Figure 6A), showing the polymer sheet and diamond particles positioned within the pores of the sheet to form the first region. Figures 6A and 6B show surface SEM images of ePTFE filled and / or embedded with diamond particles. Figure 6C is a cross-section of the diamond-filled polymer shown in Figures 6A-6B, showing diamond particles visible throughout the entire thickness of the ePTFE film, with loose particles visible on one side of the film. These images show diamond particles 90 located within pores 93 between polymer fibrils 92. In FIG. 6C, many of the diamond particles 90 are pulled upward toward the top surface of the polymer, while some diamond particles 90 lie loosely toward the bottom surface of the polymer.

[0067] Example 2 We first provided an expanded porous polymer sheet of ePTFE, made according to the teachings of U.S. Patent No. 5,814,405 to Branca et al. Iron oxide particles with an average size of approximately 0.5 μm (agglomerates of approximately 2-8 μm) were added to a liquid carrier (tap water) to form a slurry. The porous polymer membrane was wetted with IPA solvent. As in Example 1, the water and iron oxide particle slurry was pulled through the membrane and then pushed back out. This process was repeated 10 times. In this example, the sample was dried and then subjected to a temperature of approximately 200°C. This temperature increase relieves residual stresses within the membrane. Note that membranes with higher initial expansion properties may shrink more than other membranes with lower expansion properties.

[0068] Figures 7A, 7B, and 7C are SEM images taken from a porous polymer sample containing iron oxide particles <0.5 μm in size, with aggregates ranging from approximately 2 μm to 8 μm, held within the pores of the polymer produced in this example. Figures 7A-7C are shown with notations indicating the magnification and scale of each SEM image. Figures 7B and 7C are higher-magnification SEM images taken from the same sample of this example (shown in Figure 7A) containing iron oxide particles 94 located within the polymer. Figure 7A is at 100x magnification, and the scale indicates a length of 500 μm on the image (as the distance between two consecutive vertical markers represents 50 μm). Shown at the bottom of the image is a 10.0 kV 5.6 mm x 100 BSE-COMP 08 / 07 / 2020. Figure 7B is at 1000x magnification, and the scale indicates a length of 50 μm on the image (as the distance between two consecutive vertical markers represents 5 μm). Shown at the bottom of the image is a 10.0 kV 5.6 mm x 1.00 kBSE-COMP 08 / 07 / 2020. Figure 7C is at 1000x magnification, with the scale indicating a 50 μm length on the image (so that the distance between two consecutive vertical markers represents 5 μm). Shown at the bottom of the image is a 10.0 kV 10.0 mm x 1.00 kBSE+BSE 08 / 07 / 2020. Figures 7A and 7B are SEM images of the surface of a polymer sheet containing a first region having polymer and iron oxide particles 94. Figure 7C is a cross-section of the iron oxide-filled polymer shown in Figures 7A-7B, where embedded iron oxide particles are visible throughout the thickness of the ePTFE film. These images show that the iron oxide particles 94 are located within pores 93 between the polymer fibrils 92. Compared to the larger particles 90 of Example 1 (FIG. 6C), the smaller particles 94 of this Example 2 (FIG. 7C) were more likely to be pulled completely through the ePTFE sheet.

[0069] Prediction example 3 It is contemplated that a laminate may be used to aid the infusion process. Membranes such as the Branca membranes of Examples 1 and 2 above can have an additional membrane laminated to one side. This membrane can be very thin and have a much smaller or denser microstructure than the Branca membrane. Particles are applied from the Branca membrane side using positive pressure from the Branca membrane side, negative pressure from the opposite side, or both. The solid particles penetrate the microstructure and stop at the interface of the denser porous region. Once the Branca membrane is "filled" with particles, the infusion process ends, followed by a capping region and / or shrinkage process. This contemplated process is described in this disclosure with reference to Figures 5A and 5B and can be applied for use with this membrane. (Aspect) (Aspect 1) 1. A sorptive polymer composite article comprising a first region comprising a solid sorbent and a first porous polymer, said first porous polymer comprising a plurality of pores, said first region having at least a portion of the solid sorbent immobilized within at least a portion of the pores of said first porous polymer, and said first region configured to receive carbon dioxide through said first porous polymer and adsorb carbon dioxide onto said solid sorbent. (Aspect 2) 2. The sorptive polymer composite article of embodiment 1, wherein the solid sorbent is an ion exchange resin, a zeolite, activated carbon, alumina, a metal organic framework, or polyethyleneimine (PEI). (Aspect 3) 2. The sorbent polymer composite article of embodiment 1, further comprising a second region having a second porous polymer and a third region having a third porous polymer, wherein the second porous polymer in the second region and the third porous polymer in the third region are hydrophobic. (Aspect 4) 4. The sorbent polymer composite article of embodiment 3, wherein the first porous polymer, the second porous polymer, and the third porous polymer are the same. (Aspect 5) 2. The sorbent polymer composite article of embodiment 1, wherein the first region has a thickness of less than 5.0 mm. (Aspect 6) 2. The sorbent polymer composite article of embodiment 1, wherein the first porous polymer of the first region is expanded polytetrafluoroethylene, polytetrafluoroethylene, or expanded polyethylene. (Aspect 7) 2. The sorbent polymer composite article of embodiment 1, wherein the tensile strength of the first porous polymer after the solid sorbent is immobilized in at least a portion of the pores of the first porous polymer remains approximately equal to the original tensile strength of the first porous polymer before the solid sorbent was immobilized in at least a portion of the pores of the first porous polymer. (Aspect 8) The sorbent polymer composite article of embodiment 3, wherein the second region is disposed on a first side of the first region and the third region is disposed on a second side of the first region. (Aspect 9) The sorbent polymer composite article of claim 3, wherein the second porous polymer and the third porous polymer of the second region and the third region, respectively, are at least one of polytetrafluoroethylene, expanded polytetrafluoroethylene, and expanded polyethylene. (Aspect 10) providing a first porous polymer having a plurality of pores; providing a solid sorbent; combining the sorbent with the first porous polymer such that at least a portion of the sorbent is disposed within the pores of the first porous polymer; and immobilizing the solid sorbent within the pores of the first porous polymer; A method of combining a solid sorbent with a first porous polymer, comprising the steps of: (Aspect 11) The step of combining the sorbent with the porous polymer includes applying a slurry containing the sorbent to the first porous polymer. delivery 11. The method of embodiment 10, comprising: (Aspect 12) The method of embodiment 11, wherein the slurry further comprises a carrier. (Aspect 13) 11. The method of embodiment 10, wherein combining the sorbent and the first porous polymer comprises applying the sorbent in the form of dry particles to the first porous polymer under a forced air flow. (Aspect 14) The step of immobilizing the solid sorbent comprises: applying a solvent to the combination of the first porous polymer and the sorbent; and evaporating the solvent; 11. The method of embodiment 10, further comprising the step of: (Aspect 15) 15. The method of embodiment 14, wherein the evaporating step shrinks the pore size of the plurality of pores in the first porous polymer. (Aspect 16) 11. The method of embodiment 10, wherein the immobilizing step comprises applying heat to the first porous polymer and the sorbent. (Aspect 17) 17. The method of embodiment 16, wherein applying heat to the first porous polymer and the sorbent shrinks the pore size of the plurality of pores in the first porous polymer. (Aspect 18) 11. The method of embodiment 10, wherein the immobilizing step further comprises attaching a second region to the first porous polymer having a sorbent material. (Aspect 19) 20. The method of embodiment 18, wherein the attaching process comprises laminating the second region to the first porous polymer having the sorbent material. (Aspect 20) a first porous polymer comprising a plurality of nodes, a plurality of fibrils connecting adjacent nodes, and a plurality of pores defined by said nodes and said fibrils; and a plurality of solid particles held within said pores in a first state and immobilized within said pores in a second state; Including, The first porous polymer is the first state in which the fibrils are substantially straight; and a second state in which the fibrils are substantially wavy or tortuous and the pores are smaller in size than in the first state; 1. An entrained polymer composite article comprising: (Aspect 21) The plurality of solid particles are Career, and a sorptive material coating the carrier; 21. The entrained polymer composite article of embodiment 20, comprising: (Aspect 22) 21. The entrained polymer composite article of embodiment 20, wherein the solid particles have an average particle size of about 0.1 μm to about 100 μm. (Aspect 23) a second porous polymer region; a third porous polymeric region; and an end seal region extending between the second porous polymer region and the third porous polymer region; further comprising the first porous polymer is sandwiched between the second porous polymer region and the third porous polymer region; 21. The entrained polymer composite article of claim 20, wherein the second porous polymer region, the third porous polymer region, and the edge seal region cooperate to protect the solid particles within the first porous polymer region.

Claims

1. 1. A sorptive polymer composite article comprising a first region comprising a solid sorbent and a first porous polymer, said first porous polymer being shrinkable and comprising a plurality of fibrils defining a plurality of pores, said first region having at least a portion of the solid sorbent immobilized within at least a portion of the pores of said first porous polymer upon shrinkage of said fibrils, and said first region being configured to receive carbon dioxide through said first porous polymer and adsorb carbon dioxide onto said solid sorbent.

2. The sorptive polymer composite article of claim 1 , wherein the solid sorbent is an ion exchange resin, a zeolite, activated carbon, alumina, a metal organic framework, or polyethyleneimine (PEI).

3. The sorbent polymer composite article of claim 1 or 2, further comprising a second region having a second porous polymer and a third region having a third porous polymer, wherein the second porous polymer in the second region and the third porous polymer in the third region are hydrophobic.

4. The sorbent polymer composite article of claim 3 , wherein said first porous polymer, said second porous polymer, and said third porous polymer are the same.

5. The sorbent polymer composite article of claim 1 , wherein said first region has a thickness of less than 5.0 mm.

6. The sorbent polymer composite article of claim 1 , wherein said first porous polymer of said first region is expanded polytetrafluoroethylene, polytetrafluoroethylene, or expanded polyethylene.

7. 2. The sorbent polymer composite article of claim 1, wherein the tensile strength of the first porous polymer after the solid sorbent is immobilized within at least a portion of the pores of the first porous polymer remains equal to the original tensile strength of the first porous polymer before the solid sorbent is immobilized within at least a portion of the pores of the first porous polymer.

8. The sorbent polymer composite article of claim 3 , wherein said second region is disposed on a first side of said first region and said third region is disposed on a second side of said first region.

9. The sorbent polymer composite article of claim 3, wherein the second porous polymer and the third porous polymer of the second region and the third region, respectively, are at least one of polytetrafluoroethylene, expanded polytetrafluoroethylene, and expanded polyethylene.

10. providing a first porous polymer having a plurality of pores; providing a solid sorbent; combining the sorbent with the first porous polymer such that at least a portion of the sorbent is disposed within pores of the first porous polymer, the pore size of the pores being defined by a plurality of contractible fibrils; and immobilizing the solid sorbent within the pores of the first porous polymer by shrinking the plurality of fibrils; A method of combining a solid sorbent with a first porous polymer, comprising the steps of:

11. The method of claim 10 , wherein combining the sorbent and the porous polymer comprises delivering a slurry including the sorbent to the first porous polymer.

12. The method of claim 11 , wherein the slurry further comprises a liquid carrier.

13. The method of claim 10 , wherein combining the sorbent with the first porous polymer comprises applying the sorbent in dry particulate form to the first porous polymer under a forced air stream.

14. The step of immobilizing the solid sorbent comprises: applying a solvent to the combination of the first porous polymer and the sorbent; and evaporating the solvent; The method of claim 10 further comprising the steps of:

15. The method of claim 14 , wherein the evaporating step shrinks the pore size of the plurality of pores in the first porous polymer.

16. The method of claim 10 , wherein the immobilizing step comprises applying heat to the first porous polymer and the sorbent.

17. 17. The method of claim 16, wherein applying heat to the first porous polymer and the sorbent shrinks the pore size of the plurality of pores in the first porous polymer.

18. The method of any one of claims 10 to 17, wherein the immobilizing step further comprises attaching a second region to the first porous polymer having a sorbent material.

19. 20. The method of claim 18, wherein the attaching process comprises laminating the second region to the first porous polymer having the sorbent material.

20. a first porous polymer including a plurality of nodes, a plurality of fibrils that are contractible and connect adjacent nodes, and a plurality of pores defined by the nodes and the fibrils; and a plurality of solid particles held within said pores in a first state and immobilized within said pores in a second state by contraction of said plurality of fibrils; Including, The first porous polymer is the first state in which the fibrils are straight; and a second state in which the fibrils are wavy or tortuous and the pores are smaller in size than in the first state; 1. An entrained polymer composite article comprising:

21. The plurality of solid particles are Career, and a sorptive material coating the carrier; 21. The entrained polymer composite article of claim 20, comprising:

22. The entrained polymer composite article of claim 20, wherein the solid particles have an average particle size of from 0.1 μm to 100 μm.

23. a second porous polymer region; a third porous polymeric region; and an end seal region extending between the second porous polymer region and the third porous polymer region; further comprising the first porous polymer is sandwiched between the second porous polymer region and the third porous polymer region; The entrained polymer composite article of any one of claims 20-22, wherein the second porous polymer region, the third porous polymer region, and the edge seal region cooperate to protect the solid particles within the first porous polymer region.

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