Articles for attenuating electromagnetic radiation

Abstract

An article is provided having a wall comprised of a composition including a polymer matrix and a plurality of CNTs homogeneously dispersed in the polymer matrix, the polymer matrix including a thermoplastic polymer having a three-dimensional network structure, the weight percentage of the CNTs relative to the polymer matrix being 0.00001-5%, and the polymer matrix further including a surfactant. Additionally, the article is configured to attenuate electromagnetic radiation.

Description

[Technical field]

[0001] cross reference This application claims priority to Israeli Patent Application No. 292256, filed April 13, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present invention is in the field of polymeric articles containing carbon nanoparticles and their uses, such as for attenuating electromagnetic radiation. [Background technology]

[0003] Various composite materials containing conductive additives (such as carbon nanotubes, carbon fibers, and metal particles) dispersed in a thermoplastic insulating polymer matrix and characterized by enhanced electrical conductivity have been the subject of theoretical and experimental research in the last decades due to their wide variety of applications in the electrical and electronics industries. Specifically, the electromagnetic interference (EMI) attenuation or shielding properties of such composites have been evaluated. Summary of the Invention [Problem to be solved by the invention]

[0004] Most of the EMI shielding composites known in the art require large amounts of conductive additives and tedious processing, which affects the industrial feasibility of articles containing such composites. Thus, there is an unmet need to reduce the concentration of conductive additives in the composite to improve cost-effectiveness, resulting in a composite that (i) can be processed by conventional means such as extrusion and molding, and (ii) substantially retains the original mechanical properties of the thermoplastic polymer. [Means for solving the problem]

[0005] According to one aspect of the invention, there is provided an article comprising a wall, the wall comprising a polymer matrix and a plurality of CNTs homogeneously dispersed in the polymer matrix, the polymer matrix comprising a thermoplastic polymer, a weight percentage of the CNTs relative to the polymer matrix being 0.00001-5%, the polymer matrix further comprising a surfactant, and the article configured to attenuate electromagnetic radiation in a wavelength range of 1 kHz-150 GHz. In one embodiment, the CNTs comprise single-walled CNTs. In one embodiment, the polymer matrix comprises a three-dimensional network structured thermoplastic polymer.

[0006] In one embodiment, the matrix is ​​free of agglomerated particles of thermoplastic polymer.

[0007] In one embodiment, the thermoplastic polymer has a molecular weight of at least 10 10 It is characterized by a surface resistivity in Ω·cm.

[0008] In one embodiment, the article comprises at least 10 2 It is characterized by a surface resistivity in Ω·cm.

[0009] In one embodiment, the walls are characterized by a thickness between 100 nm and 10 mm.

[0010] In one embodiment, the weight ratio of CNTs per area of ​​the article is between 0.05 and 75 g / m for a thickness of between 40 μm and 1 mm. 2 It is.

[0011] In one embodiment, the w / w ratio of surfactant to CNTs in the wall is between 10:1 and 0.5:1.

[0012] In one embodiment, the w / w ratio of surfactant to polymer in the wall is between 0.00001% and 10%.

[0013] In one embodiment, the thermoplastic polymer is characterized by a melting temperature of at least 100°C.

[0014] In one embodiment, the article further comprises inorganic material in the form of: (i) fibers; (ii) particulate matter, or both.

[0015] In one embodiment, the inorganic material includes any one of a glass, a metal, a mineral, and a ceramic, or any combination thereof.

[0016] In one embodiment, the article is in the form of a film.

[0017] In one embodiment, the article further comprises an additional layer in contact with at least one surface of the wall.

[0018] In one embodiment, the additional layer comprises a polymer, optionally a high strength polymer, an inorganic material, or both.

[0019] In one embodiment, the article is bondable to a substrate, the bond being by physical or chemical adhesion, or welding.

[0020] In one embodiment, the attenuation is at least 5 dB when compared to a similar article without the CNTs.

[0021] In one embodiment, the attenuation is at least 10 dB over an electromagnetic radiation wavelength range of 1 to 110 GHz.

[0022] In one embodiment, each of (i) the CNTs and (ii) the surfactant is present in the wall at a w / w concentration of 0.00001% to 2%, and the article is 2 ~10 12 It is characterized by a surface resistivity in Ω·cm.

[0023] In one embodiment, the article is manufactured by a process including any of the following: extrusion, injection, hot blown film, and molding, or any combination thereof.

[0024] In one embodiment, the wall substantially maintains the properties of the thermoplastic polymer without the surfactant and the CNTs, the properties being any one of tensile strength, Young's modulus, elongation at break, melt strength, or any combination thereof.

[0025] In order that the invention may be more fully understood, it will now be described in connection with specific examples and embodiments with reference to the following illustrative figures. [Brief description of the drawings]

[0026] [Figure 1A] 1 is a graph showing the EMI attenuation of an exemplary article of the invention composed of polyamide 6 containing approximately 1% w / w CNTs (**) and an article having substantially the same chemical composition and characterized by a substantially non-homogeneous distribution of CNTs (*). [Figure 1B] 1 is an image of an exemplary plaque of the present invention. [Figure 1C] 1 is an image of a control plaque of the invention, where CNT agglomerated particles are visually detectable on the surface of the article (white arrows), indicating a heterogeneous distribution of CNTs. [Diagram 2] FIG. 2 is a schematic diagram of the EMI attenuation measurement described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] In one aspect of the invention, an article is provided comprising a composition, the composition comprising a polymer matrix and a plurality of carbon nanotubes (CNTs) homogeneously dispersed (or uniformly distributed) in the polymer matrix, the polymer matrix comprising a thermoplastic polymer, the weight percentage of the CNTs in the composition is 0.00001-5%, and the composition further comprises a surfactant. In some embodiments, the composition and / or article is an extrudate. In some embodiments, the article is shape-set by a process selected from extrusion, injection, hot blown film, molding (e.g., cast molding, compression molding, rotational molding), or any combination thereof. In some embodiments, the article of the invention is configured to attenuate electromagnetic radiation in the wavelength range of 1 kHz to 150 GHz. The term "wavelength range" as used herein includes any one of the subranges within the ranges disclosed above and any one of the individual wavelength numbers.

[0028] In some embodiments, the terms "composition" and "composition of the invention" are used interchangeably herein and refer to a plurality of CNTs (e.g., SWCNTs) embedded or incorporated in a polymer matrix, as described herein, and further comprising a surfactant. In some embodiments, the composition of the invention consists essentially of a thermoplastic polymer, CNTs, and surfactant, and the thermoplastic polymer, CNTs, and surfactant, and their ratios and / or concentrations in the composition, are as described herein.

[0029] In some embodiments, the article is a solid. In some embodiments, the article includes a polymer matrix and a plurality of CNTs (e.g., SWCNTs) embedded or incorporated in the polymer matrix. In some embodiments, the plurality of CNTs (e.g., SWCNTs) are homogeneously distributed in the matrix.

[0030] In some embodiments, the article comprises a wall, the wall being comprised of the composition of the invention (e.g., consisting essentially of a polymer matrix and a plurality of CNTs embedded or incorporated in the polymer matrix). In some embodiments, the wall is a radiation attenuator, and radiation refers to electromagnetic radiation in the wavelength range of 1 KHz to 150 GHz or any range therebetween. In some embodiments, the wall is in the form of a homogenous layer (e.g., a single-layer wall or a multi-layer wall). In some embodiments, the wall is a composite material, as disclosed below. In some embodiments, the wall is a solid single-layer wall or a multi-layer wall, and consists essentially of a composite material, which is or comprises a composition of the invention. In some embodiments, at least 90%, at least 95%, at least 97%, at least 99%, 90-100%, 95-100%, 90-99%, 95-99%, 97-100%, 97-99% of the weight of the wall is comprised of the composition of the invention.

[0031] In some embodiments, the walls are characterized by a thickness of 100 nm to 10 cm, 100 nm to 1 μm, 1 μm to 10 cm, 10 μm to 10 cm, 10 μm to 5 cm, 20 μm to 10 cm, 30 μm to 10 cm, 40 μm to 10 cm, 50 μm to 10 cm, 100 μm to 10 cm, 10 μm to 1 cm, 1 to 10 cm, 1 to 5 cm, 5 to 10 cm, 50 μm to 5 cm, 50 μm to 1 cm, 50 μm to 3 cm, or any range therebetween.

[0032] In some embodiments, the walls and / or articles are characterized by length / width dimensions of 0.1 cm to 100 m, 1 cm to 100 m, 1 cm to 1 m, 1 to 100 m, 1 to 10 m, 10 m to 100 m, or any range therebetween.

[0033] In some embodiments, each of the plurality of CNTs is in contact with or bound to one or more surfactant molecules. In some embodiments, the surfactant molecules substantially prevent aggregation of the CNTs. In some embodiments, the surfactant increases the miscibility of the CNTs with the polymer matrix. In some embodiments, the surfactant increases the stability of the composition. In some embodiments, the surfactant increases or induces dispersibility of the CNTs in the polymer matrix. In some embodiments, the surfactant prevents separation of the CNTs from the thermoplastic polymer.

[0034] In some embodiments, the polymer matrix comprises a thermoplastic polymer, as described below. In some embodiments, the polymer matrix is ​​an entangled matrix composed of randomly distributed polymer chains and surfactant molecules. In some embodiments, the polymer chains are in contact with the surfactant molecules, thereby forming the matrix. In some embodiments, the matrix comprises a three-dimensional network of randomly distributed polymer chains. In some embodiments, the polymer chains are randomly distributed in the matrix. In some embodiments, the matrix is ​​substantially free of aligned or oriented polymer chains. In some embodiments, the matrix is ​​substantially free of aligned or oriented polymer chains in a particular direction. In some embodiments, the randomly distributed polymer chains and surfactant form a three-dimensional network with voids between the chains. In some embodiments, the polymer chains are randomly distributed in the matrix, thus forming a plurality of holes (or voids). In some embodiments, the matrix further comprises any material incorporated within and / or present between the layers. In some embodiments, the matrix is ​​free of coalesced polymer particles. In some embodiments, the matrix is ​​an amorphous matrix.

[0035] In some embodiments, the polymer matrix comprises a thermoplastic polymer, as described below. In some embodiments, the thermoplastic polymer molecules that make up the polymer matrix are chemically identical polymers. In some embodiments, the polymer matrix comprises multiple chemically distinct polymers. In some embodiments, the polymer matrix comprises a mixture of chemically distinct polymer species.

[0036] In some embodiments, the thermoplastic polymer of the present invention forms a matrix to which the CNTs (e.g., SWCNTs) are contacted or bonded. In some embodiments, the CNTs (e.g., SWCNTs) are physisorbed and / or chemisorbed on or within the polymer matrix. In some embodiments, the bond is by non-covalent bonding. In some embodiments, the CNTs (e.g., SWCNTs) are encapsulated by the matrix. In some embodiments, the CNTs (e.g., SWCNTs) provide reinforcement and additional physical properties (e.g., attenuation of electromagnetic radiation) to the composite. In some embodiments, the CNTs (e.g., SWCNTs) induce or enhance electrical conductivity in the article of the present invention. In some embodiments, the CNTs provide EMI shielding properties to the wall.

[0037] In some embodiments, the term "bond" refers to any non-covalent bond or interaction, such as electrostatic bonds, dipole-dipole interactions, van der Waals interactions, ionic interactions, hydrogen bonds, hydrophobic interactions, pi-pi stacking, London forces, etc. In some embodiments, the non-covalent bond or interaction is a stable bond or interaction, where stable is as described herein.

[0038] In some embodiments, the article or a wall of the article is a composite material. In some embodiments, the article of the present invention is a solid composite. In some embodiments, the article of the present invention is in the form of a layered composite. In some embodiments, the article or composite material (also referred to herein as a "composite") of the present invention is substantially homogenous throughout.

[0039] As used herein, a "composite material" is a material made from two or more constituent materials that have significantly different chemical or physical properties and that, when fused, produce a material with properties that differ from those of the individual components.

[0040] In some embodiments, a composite refers to a substantially homogeneous material that cannot be easily separated into its individual components (e.g., the CNTs of the present invention, the surfactant, and the thermoplastic polymer). In some embodiments, the composite does not substantially undergo phase separation or disintegration (also referred to herein as a "stable" composite). In some embodiments, the composite is substantially free of multilayer structure. Those skilled in the art will recognize that there are three types of composites (e.g., nanocomposites): non-intercalated nanocomposites (microcomposites), intercalated nanocomposites, or exfoliated nanocomposites.

[0041] In some embodiments, a homogeneous composite as used herein comprises CNTs substantially uniformly distributed in a matrix. In some embodiments, a homogeneous composite as used herein comprises CNTs substantially uniformly incorporated in a matrix. In some embodiments, a homogeneous composite as used herein is substantially free of CNT agglomerate particles (or aggregates). In some embodiments, a homogeneous composite as used herein comprises agglomerate particles of 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, or any range therebetween, by weight, relative to the total CNT content of the composite of the present invention.

[0042] In some embodiments, a homogenous composite, as used herein, contains no more than 20%, no more than 15%, no more than 10%, no more than 5%, no more than 3%, no more than 1%, or any range therebetween, of the total CNT content within the cross-section of the composite. One of ordinary skill in the art will appreciate that the degree of CNT agglomeration can be assessed by analysis of the microstructure of the material, including but not limited to TEM or SEM micrographs. In some embodiments, at least 70%, at least 80%, at least 90%, at least 92%, at least 95%, at least 97%, at least 99% of the CNTs of the composite are organized into a plurality of discrete domains (or discrete clusters), each domain characterized by a width (or cross-sectional) and / or length dimension of 1-500 nm, 1-100 nm, 1-200 nm, 1-10 nm, 1-50 nm, 10-500 nm, 10-100 nm, 50-500 nm, 50-100 nm, 100-500 nm, 50-200 nm, or any range therebetween, or less than 10 μm, less than 5 μm, or less than 1 μm.

[0043] In some embodiments, the CNT agglomerated particles are characterized by at least one dimension (e.g., thickness) of at least 1 μm, at least 5 μm, at least 10 μm, at least 50 μm, at least 100 μm, at least 500 μm, or any range therebetween. In some embodiments, the at least one dimension of the agglomerated particles refers to an average value.

[0044] The homogeneity (e.g., the presence of CNT agglomerated particles) of the composite materials of the present invention can be assessed using appropriate microscopic analysis of the material surface by TEM, SEM, etc. Analysis of the micrographs (e.g., TEM and / or SEM micrographs) can be performed, for example, by image processing software well known in the art. Additionally, homogeneity can be assessed by examining the composition of the article (e.g., determining the concentration of CNTs and / or surfactants) at at least three different locations. The standard deviation of the measured concentration values ​​is believed to be 20% or less, 10% or less, 5% or less, 1% or less, or any range therebetween.

[0045] Alternatively, homogeneity can be evaluated by examining the EMI (electromagnetic interference) attenuation or shielding properties of the composition or article. The inventors have surprisingly found that a substantially non-uniform distribution of CNTs in the walls of an exemplary article of the present invention results in inferior EMI shielding compared to an article of the present invention characterized by a homogeneous CNT distribution. Furthermore, it has been found that an article having a non-uniform distribution of CNTs has substantially the same (e.g., ±10%, or ±20%, or less) EMI attenuation as a pure polymer, e.g., the same polymer without CNTs.

[0046] In some embodiments, the article or composition of the present invention consists essentially of the thermoplastic polymer, CNTs, and surfactants described herein. In some embodiments, at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 93%, at least 95%, at least 97%, at least 99%, or any range therebetween, of the weight of the article of the present invention is composed of thermoplastic polymer. In some embodiments, at least 80%, at least 90%, at least 95%, at least 99%, or at least 99.9% of the polymer matrix is ​​composed of thermoplastic polymer.

[0047] In some embodiments, the CNTs and / or surfactant (and optionally any further components of the composition) are compatible or miscible with the thermoplastic polymer in the molten state. In some embodiments, the thermoplastic polymer in the molten state is compatible or miscible with the further components of the composition and forms a composite (e.g., upon cooling below the glass transition temperature of the thermoplastic polymer). In some embodiments, the thermoplastic polymer in the molten state is miscible with the CNTs and the resulting mixture is substantially free of phase separation and / or agglomeration.

[0048] In some embodiments, the thermoplastic polymer in the molten state is compatible with the additional components of the composition to result in a homogeneous composite (e.g., after solidification of the mixture). In some embodiments, the thermoplastic polymer and the CNTs, and optionally a surfactant, can form a homogeneous composite.

[0049] In some embodiments, the thermoplastic polymer has a melting point greater than 100°C, 110°C, 120°C, 150°C, 200°C, 250°C, 300°C, 350°C, 400°C, 500°C, 600°C, or any range or value therebetween.

[0050] In some embodiments, the thermoplastic polymer has a melting point of 100-650° C., 100-200° C., 200-400° C., 400-650° C., or any range or value therebetween.

[0051] In some embodiments, the thermoplastic polymer is selected from polyamide (PA) (e.g., PA6, PA6,6, etc.), polystyrene, acrylonitrile, butadiene styrene, polyacrylate, polycarbonate, polyacrylate ester, polymethacrylate, polyacrylamide, polyolefin, poly(bisphenol A-co-carbonate), poly(bisphenol A-co-terephthalate), polyvinyl alcohol, polyvinyl chloride and polyacrylonitrile, polyphenylene, polyetheretherketone, polyphenylene sulfide, polyetherimide, polyethersulfone, polyacetal, polyoxymethylene, polyphenylene oxide, polysulfone, polyimide, polyamideimide, polytetrafluoroethylene, any copolymer thereof, or any combination thereof. In some embodiments, the polymer comprises a thermoplastic resin (e.g., a short chain polymer or oligomer).

[0052] In some embodiments, the thermoplastic polymer comprises an acrylate-based polymer, hi some embodiments, the acrylate-based polymer is selected from the group consisting of polyacrylates, polyacrylate esters, polymethacrylates, polyethyl methacrylates, polymethacrylate esters, polyethyl methacrylate esters, any copolymers thereof, or any combinations thereof.

[0053] In some embodiments, the thermoplastic polymer comprises polystyrene and / or its derivatives (eg, substituted polystyrenes such as poly(halo-styrenes), poly(alkyl-styrenes), etc.).

[0054] In some embodiments, the thermoplastic polymer comprises a polyolefin or a mixture of polyolefins. Non-limiting examples of polyolefins include, but are not limited to, polyethylene (PE), LDPE, MDPE, HDPE, polypropylene (PP), polybutene, polyethylene-butene copolymer, polyethylene-propylene copolymer, atactic poly-α-olefin (APAO), amorphous poly-α-olefin (APAO), and syndiotactic polypropylene (SPP). Other polyolefins are well known in the art.

[0055] In some embodiments, the thermoplastic polymer comprises a polyamide or a mixture of polyamides, such as nylon. Various polyamides, such as PA6, PA12, PA6,6, etc., are known in the art.

[0056] In some embodiments, the thermoplastic polymer forming or defining the polymer matrix is ​​substantially non-conductive. 10 Ω cm, at least 10 11 Ω cm, at least 10 13 Ω cm, at least 10 14 Ω cm, at least 10 15In some embodiments, the thermoplastic polymer is substantially free of conductive polymers.

[0057] In some embodiments, the thermoplastic polymer has a molecular weight of at least 10 10 Ω cm, at least 10 11 Ω cm, at least 10 13 Ω cm, at least 10 14 Ω cm, at least 10 15 It is characterized by a surface resistivity in Ω·cm, or any range therebetween.

[0058] In some embodiments, the thermoplastic polymer is characterized by a surface resistivity of greater than 1.05E+06 Ω, greater than 1.05E+09 Ω, greater than 1.05E+12 Ω, or any range therebetween.

[0059] In some embodiments, the compositions of the present invention comprise CNTs (eg, SWCNTs) embedded in a polymer matrix and a surfactant.

[0060] In some embodiments, a CNT is or comprises a carbon nanostructure (e.g., a single carbon nanostructure type or multiple distinct carbon nanostructure types. The term "carbon nanostructure" is familiar to those of skill in the art and refers to 2D carbon materials such as carbon fibers, carbon nanotubes (single- or multi-walled, linear or branched), carbon black, graphene, and fullerenes, or any combination thereof, among others.

[0061] In some embodiments, the CNTs are or comprise single-walled carbon nanotubes (SWCNTs). In some embodiments, the CNTs are conductive CNTs (e.g., conductive SWCNTs). In some embodiments, the CNTs optionally comprise multi-walled carbon nanotubes (MWCNTs). In some embodiments, the CNTs comprise SWCNTs and optionally comprise additional carbon nanostructures.

[0062] In some embodiments, the CNTs are characterized by an aspect ratio of 130-10,000, 130-200, 130-1,000, 1000-5,000, 5000-10,000, 130-7,000, 7000-10,000, or any range therebetween.

[0063] In some embodiments, the w / w concentration of CNTs in the article is 0.00001%-5%, 0.00005%-5%, 0.00001%-0.00005%, 0.00001%-0.0001%, 0.00001%-0.001%, 0.0001%-5%, 0.0001%-2%, 0.001%-5%, 0.001%-2%, 0.001%- 1%, 0.001%-0.005%, 0.005%-0.01%, 0.01%-5%, 0.01%-2%, 0.01%-1%, 0.01%-0.5%, 0.01%-0.05%, 0.05%-0.1%, 0.1%-0.5%, 0.5%-1%, 1%-2%, 2%-3%, 3%-5%, 5%-10%, or any range therebetween. In some embodiments, the w / w concentration of CNTs in an article refers to the weight percentage of CNTs relative to the polymer matrix in the article.

[0064] In some embodiments, the w / w concentration of CNTs in the article (also referred to herein as an effective amount) is sufficient to impart energy attenuation properties to the article, where the attenuation is as described herein. In some embodiments, energy refers to electromagnetic radiation. In some embodiments, the w / w concentration of CNTs in the article is sufficient to enhance the attenuation of electromagnetic radiation by the article of the invention, where the enhancement refers to energy attenuation compared to a control. In some embodiments, the control is a similar article without CNTs. In some embodiments, the control is a similar article comprising CNTs distributed heterogeneously in a polymer matrix. In some embodiments, the control is a similar thermoplastic polymer without CNTs and / or surfactants.

[0065] Those skilled in the art will understand that the energy attenuation properties of the article strongly depend on the concentration of CNTs and their distribution in the polymer matrix. The main challenge is the development of an article characterized by energy attenuation and at the same time with reduced weight (e.g., compared to metal-based electromagnetic radiation shields). Furthermore, it is advantageous to keep the CNT concentration as low as possible, which contributes to the cost-effectiveness of the article.

[0066] The term "attenuation" as used herein refers to a reduction in the intensity (or amplitude) of an electromagnetic wave (or electromagnetic radiation). Specifically, the reduction in intensity refers to an electromagnetic wave propagating through a wall (e.g., in a direction perpendicular to the longitudinal axis of the article or wall). The term "attenuation" as used herein refers to the ability of the article of the present invention to reduce the intensity of incident electromagnetic radiation, where the reduction is relative to the initial intensity of the incident radiation.

[0067] Those skilled in the art will appreciate that attenuation may be induced by reflection, absorption, or dissipation of electromagnetic radiation by at least one wall of the article of the present invention.

[0068] The damping of exemplary articles of the present invention can be measured according to the method described in the Examples section.

[0069] In some embodiments, the decrease or attenuation (including any grammatical form thereof) is at least 5-fold, at least 10-fold, at least 100-fold, at least 1000-fold, at least 10-fold, or at least 10-fold compared to a control. 5 1 in 10 at least 7 1 in 10 at least 10 1 in 10 at least 15 1 in 10 at least 20 1 in 10 at least 30 The term "control" as used herein refers to an article comprising pure polymer and having substantially the same dimensions.

[0070] In some embodiments, the reduction or attenuation (including any grammatical forms thereof) is about 2 dB, about 5 dB, about 10 dB, about 15 dB, about 20 dB, about 25 dB, about 30 dB, at least 2 dB, at least 5 dB, at least 10 dB, at least 15 dB, at least 20 dB, at least 25 dB, at least 30 dB, or any range therebetween.

[0071] In some embodiments, the effective amount of CNTs in the wall of the article or in the article is at most 5%, at most 3%, at most 2%, at most 1%, at most 0.5%, at most 0.1%, at most 0.05%, at most 0.01% w / w, at most 0.001% w / w, at most 0.0001% w / w, or any range therebetween.

[0072] In some embodiments, the effective amount of CNTs in the wall of the article or in the article is at least 0.00001%, at least 0.00005%, at least 0.0001%, at least 0.0005%, at least 0.001%, at least 0.005%, or any range therebetween.

[0073] In some embodiments, the effective amount of CNTs in the wall of the article or in the article is 0.00001-5%, 0.00005-5%, 0.0001%-5%, 0.0005%-5%, 0.001-5%, 0.005-5%, 0.005-3%, 0.01-1%, 0.05-2%, or any range therebetween.

[0074] In some embodiments, the content of non-SWCNT carbon nanostructures (e.g., MWCNTs, etc.) in the articles and / or compositions described herein is at most 30%, at most 25%, at most 20%, at most 15%, at most 10%, at most 5%, at most 1%, or any range therebetween, by weight relative to the total CNT content of the article.

[0075] In some embodiments, total CNT content is referred to herein as the weight percentage of SWCNTs and, optionally, at least one additional carbon nanostructure (MWCNTs, carbon black, fullerenes, graphene, etc.) in an article of the invention.

[0076] In some embodiments, the composition is substantially free of additional carbon nanoparticles. In some embodiments, the composition is substantially free of inorganic materials (e.g., metals, glasses, minerals, any particles thereof, or any fibers). In some embodiments, the composition is substantially free of fibers (e.g., carbon fibers, etc.). In some embodiments, the terms carbon nanostructures and carbon nanoparticles are used interchangeably herein.

[0077] In some embodiments, the effective amount of CNTs in the article is between 0.05 and 75 g / m of CNTs by weight per area of ​​the article. 2 , 0.05~0.1g / m 2 , 0.1~75g / m 2 , 0.1~1g / m 2 , 1~75g / m 2 , 1~10g / m 2 , 0.1~10g / m 2 , 0.1~20g / m 2, 0.1~30g / m 2 , 0.1~40g / m 2 , 0.1~50g / m 2 , 0.1~70g / m 2 , 1~50g / m 2 , 1~30g / m 2 , 10~75g / m 2 , 10~30g / m 2 , 10~50g / m 2 , 20~75g / m 2 , 20~50g / m 2 , or any range therebetween, the weight percentages relating to articles having a thickness in the range of 40 μm to 1 mm.

[0078] In some embodiments, the effective amount of CNTs in the article is at least 0.1, at least 1, at least 5, at least 10, at least 20, at least 30, or at least 40 g / m 2 or any range therebetween, the effective amount percentage being for articles having a thickness in the range of 40 μm to 1 mm.

[0079] In some embodiments, the effective amount of CNTs in the article is at most 50, at most 40, at most 30, at most 20, at most 10, at most 5, at most 1, at most 0.5, or at most 0.05 g / m 2 or any range therebetween, the effective amount percentage being for articles having a thickness in the range of 40 μm to 1 mm.

[0080] In some embodiments, the effective amount of CNTs is sufficient to provide an article configured to substantially reduce or attenuate electromagnetic radiation (as disclosed herein), such that the article is substantially non-conductive.

[0081] In some embodiments, the electrical conductivity of the article is at least 10, at least 100, at least 1000, at least 10,000, at least 100,000 times, at least 1,000,000 times, at least 10,000,000 times, or any range therebetween, greater than the electrical conductivity of the pure polymer. In some embodiments, the electrical conductivity of the article is substantially the same as the electrical conductivity of the pure polymer. In some embodiments, electrical conductivity refers to surface conductivity or volume conductivity.

[0082] In some embodiments, the article of the present invention comprises 10 13 ~1Ω cm, 10 13 ~10 12 Ω cm, 10 12 ~10 10 Ω cm, 10 10 ~10 8 Ω cm, 10 8 ~10 6 Ω cm, 10 6 ~10 4 Ω cm, 10 4 ~10 2 Ω cm, 10 2 They are characterized by a volume resistivity of ~1 Ω·cm, or any range therebetween.

[0083] In some embodiments, the article of the present invention comprises 10 13 ~1Ω cm, 10 13 ~10 12 Ω cm, 10 12 ~10 10 Ω cm, 10 10 ~10 8 Ω cm, 10 8 ~10 6 Ω cm, 10 6 ~10 4 Ω cm, 10 4 ~10 2 Ω cm, 10 2 〜1 Ω·cm, or any range therebetween, hi some embodiments, the surface resistivity is measured according to ANSI / ESD STM11.11.

[0084] In some embodiments, the article of the present invention comprises at least 10 2 , at least 10 3 , at least 10 5 , at least 10 7 , at least 10 10 , at least 10 12 It is characterized by a surface resistivity in Ω·cm, or any range therebetween.

[0085] In some embodiments, the compositions of the present invention include an effective amount of a surfactant. In some embodiments, the effective amount is an amount that substantially prevents aggregation or agglomeration of the CNTs and / or enhances the miscibility of the CNTs with the thermoplastic polymer, thereby resulting in a stable article. In some embodiments, the effective amount is an amount that induces a homogeneous distribution of the CNTs in the article or polymer matrix of the present invention.

[0086] In some embodiments, an effective amount of surfactant is a w / w concentration of surfactant relative to the thermoplastic polymer in the wall of the article of between 0.001% and 30%, between 0.00001% and 10%, between 0.00001% and 5%, between 0.00005% and 5%, between 0.0001% and 10%, between 0.0001% and 0.001%, between 0.001% and 15%, between 0.003% and 15%, between 0.005% and 15%, between 0.01% and 15%, between 0.001% and 10%, between 0.001% and 5%, between 0.01% and 15%, This includes 0.01%-10%, 0.01%-5%, 0.05%-15%, 0.05%-10%, 0.05%-5%, 0.05%-0.1%, 0.1%-0.3%, 0.3%-0.5%, 0.5%-0.7%, 0.7%-1%, 0.001%-0.01%, 0.01%-0.1%, 0.1%-1%, 1%-5%, 5%-10%, 10%-20%, 10%-15%, 15%-20%, 1%-10%, 10%-30%, or any range therebetween.

[0087] In some embodiments, the w / w concentration of the surfactant in the article is less than 1%, less than 0.7%, less than 0.5%, less than 0.3%, less than 0.1%, less than 0.05%, less than 0.01%, less than 0.005%, less than 0.001%, less than 0.0001%, less than 0.00005%, or any range therebetween of the total weight of the article.

[0088] In some embodiments, an effective amount of surfactant includes a w / w ratio of surfactant to CNTs (e.g., SWCNTs) in the article (or in the wall) of 20:1 to 10:1, 10:1 to 0.5:1, 10:1 to 1:1, 10:1 to 8:1, 8:1 to 5:1, 5:1 to 3:1, 3:1 to 2:1, 9:1 to 7:1, 7:1 to 5:1, 5:1 to 3:1, 3:1 to 1:1, 3:1 to 0.5:1, 1:1 to 1:2, or any range therebetween. In some embodiments, an effective amount of surfactant includes a w / w ratio of surfactant to CNTs (e.g., SWCNTs) in the article (or in the wall) of about 3:1 to 1:2.

[0089] In some embodiments, the surfactant is characterized by a solubility in organic solvents (e.g., polar solvents such as isopropyl alcohol, non-polar solvents such as toluene) and / or water of at least 1 g / L, at least 10 g / L, at least 50 g / L, at least 100 g / L, or any range therebetween.

[0090] In some embodiments, the surfactant is a cationic surfactant. In some embodiments, the surfactant comprises a polyalkylammonium. In some embodiments, the surfactant is or comprises a polyalkylammonium-co-polyether.

[0091] In some embodiments, the surfactant is or comprises an anionic surfactant (eg, SDBS, carboxymethylcellulose CMC) and / or a non-ionic surfactant (eg, polysiloxane).

[0092] In some embodiments, the surfactant does not include polyvinylpyrrolidone (PVP). In some embodiments, the surfactant does not include PVP and / or a copolymer comprising cellulose or a derivative thereof.

[0093] In some embodiments, the surfactant does not include surfactants suitable for implementation in dispersion polymerization (DP), also known as "latex polymerization."

[0094] In some embodiments, the compositions or articles of the present invention are processable by an extruder. In some embodiments, the compositions or articles of the present invention are extrudable. In some embodiments, the compositions or articles are flowable in a molten state. In some embodiments, the melt flow index (MFI) of the compositions or articles of the present invention is predetermined by the w / w concentration and / or chemical structure of the CNTs and / or surfactants.

[0095] In some embodiments, the compositions of the present invention are extrudable, i.e., they are chemically stable and retain their physical properties (e.g., intactness, absence of phase separation, homogenous distribution of CNTs, EMI attenuation capabilities, their physical strength) when exposed to conditions suitable for extrusion (e.g., high pressure and high temperature). In some embodiments, the compositions of the present invention have suitable rheological properties (such as flowability and / or MFI as described herein) in the molten state.

[0096] In some embodiments, the extrudable composition or article is characterized by an MFI of 0.1 to 100, 0.1 to 1, 1 to 10, 10 to 50, 50 to 100, or any range therebetween.

[0097] In some embodiments, the articles of the present invention may be manufactured and / or fabricated by extrusion of the composition.

[0098] In some embodiments, an article of the invention is made from a composition of the invention, hi some embodiments, the term article refers to a composition having a predetermined shape (e.g., a processed or shaped composition, where processing is by a method described herein).

[0099] In some embodiments, the compositions of the present invention are shapable or moldable (e.g., capable of obtaining a predetermined shape) by a process selected from extrusion, injection, hot blown film, molding (e.g., casting, compression molding, rotational molding), or any combination thereof.

[0100] In some embodiments, the articles of the invention further comprise inorganic and / or organic materials in the form of fibers and / or particles. In some embodiments, the articles of the invention further comprise a single type of inorganic material or multiple distinct types of materials. In some embodiments, the inorganic material is in the form of fibers, substantially spherical particles (e.g., nanoparticles, microparticles, or both), sheets (e.g., 2D materials), or any combination thereof.

[0101] In some embodiments, the inorganic or organic material comprises a thermoplastic polymer particle or fiber. In some embodiments, the organic material comprises a thermoplastic organic polymer. In some embodiments, the inorganic material comprises a metal, a ceramic, a glass, an ultra-hard material, any derivative thereof, or any combination thereof.

[0102] In some embodiments, the articles of the invention comprise one or more walls. In some embodiments, the articles of the invention comprise multiple walls that are in contact with or bonded to one another. In some embodiments, the one or more walls define a lumen. In some embodiments, the walls are substantially flat or curved.

[0103] In some embodiments, the term wall refers to a structural element of the article, and the shape of the wall substantially predetermines the shape of the article. In some embodiments, the wall is characterized by a uniform thickness. In some embodiments, the wall is characterized by a non-uniform thickness. In some embodiments, the wall has a 2D or 3D shape. In some embodiments, the wall is either a sphere, a hemisphere, a hollow sphere, a cylinder, a hollow cylinder, a hollow hemisphere, a cone, a pyramid, a horseshoe, or any other 3D shape. In some embodiments, the wall is substantially continuous. In some embodiments, the wall comprises one or more openings or cuts. In some embodiments, the openings are distributed in the form of a pattern on or in the wall. In some embodiments, the wall is a perforated wall. In some embodiments, the openings or holes are distributed in the form of a pattern on or in the wall. In some embodiments, the wall is in the form of a net.

[0104] In some embodiments, the openings or holes are characterized by a cross section of 100 μm to 10 cm, 100 μm to 200 μm, 100 μm to 500 μm, 500 μm to 1 mm, 1 to 5 mm, 1 to 10 mm, 1 to 10 cm, or any range therebetween.

[0105] In some embodiments, the shape of the walls and / or the pattern of the openings are predetermined by the desired shape and / or size of the EMI shielding area. In some embodiments, the walls and / or articles are shaped to provide substantial EMI shielding in a given location. In some embodiments, the walls and / or articles are shaped to provide partial EMI shielding in a given location.

[0106] In some embodiments, the wall and / or article is shaped to provide EMI reflection, EMI dissipation, or both. In some embodiments, the wall comprises an exterior surface facing incident electromagnetic radiation and an interior surface. In some embodiments, the wall provides EMI attenuation proximate the interior surface of the wall, where the EMI attenuation is as described herein.

[0107] In some embodiments, the exterior surface of the wall is characterized by a predetermined surface roughness. In some embodiments, the exterior surface of the wall is a textured surface. In some embodiments, the texture or roughness is characterized by a height dimension in the range of 1 μm to 1 mm, or any range therebetween.

[0108] In some embodiments, the articles and / or walls of the present invention are characterized by a three-dimensional shape. In some embodiments, the articles and / or walls of the present invention have any predefined 3D shape or structure. In some embodiments, the articles of the present invention have a regular or irregular shape.

[0109] In some embodiments, the article and / or wall is in the form of a layer. In some embodiments, the article and / or wall is in the form of a film. In some embodiments, the film is a substantially uniform layer. In some embodiments, the film is a solid film. In some embodiments, the article is solid (e.g., substantially solid-state and non-flowable) below the melting temperature and / or glass transition temperature of the thermoplastic polymer that comprises the article. The melting point of the thermoplastic polymer may vary depending on the chemical composition, MW, and / or density of the thermoplastic polymer.

[0110] "Uniform" or "homogeneous" when referring to a layer or film is intended to refer to a size (or thickness) distribution that varies, for example, by less than ±50%, less than ±40%, less than ±30%, less than ±20%, less than ±10%, less than ±5%, or any value therebetween. Additionally, the term homogeneous refers to a homogeneous dispersion or distribution of CNTs at a microscopic level within the matrix or composite of the present invention.

[0111] In some embodiments, the term "layer" refers to a substantially homogeneous material of substantially uniform thickness. In some embodiments, a layer or film comprises a single layer or multiple layers. In some embodiments, the terms layer and film are used interchangeably herein.

[0112] In some embodiments, the wall is in the form of a multi-layer wall. In some embodiments, the wall comprises a first layer and a second layer in contact with the outer surface of the first layer. In some embodiments, the second layer is bonded to the first layer. In some embodiments, the second layer is disposed on the first layer. In some embodiments, the second layer or the first layer is sandwiched between at least two separate layers (e.g., the first layer or the second layer, respectively). In some embodiments, the second layer and / or the first layer comprises one or more layers, the layers being the same or different (e.g., having different chemical compositions or different dimensions).

[0113] In some embodiments, the first layer comprises a composition described herein. In some embodiments, the second layer comprises any of a polymer, a high strength polymer, an inorganic material, or any combination thereof, and any of the materials comprising the second layer are independently selected from a homogenous material (e.g., a film), a fiber, a particle (e.g., nanoparticles, microparticles, or both), a sheet (e.g., a 2D material), or any combination thereof.

[0114] In some embodiments, the article or wall (e.g., in the form of a layer) can be bonded to a substrate. In some embodiments, the article can be attached to a substrate, the attachment being by physical or chemical adhesion, welding, or a combination thereof.

[0115] In some embodiments, the article or wall of the invention may be configured to operate at frequencies from 1 KHz to 150 GHz, 1 KHz to 200 GHz, 10 KHz to 150 GHz, 10 KHz to 110 GHz, 10 KHz to 130 GHz, 0.1 MHz to 150 GHz, 0.1 MHz to 200 GHz, 1 MHz to 150 GHz, 1 MHz to 130 GHz, 10 MHz to 150 GHz, 100 MHz to 150 GHz, 50 MHz to 150 GHz, 50 MHz to 200 GHz, 100 MHz to 120 GHz, 100 MHz to 110 GHz, 100 MHz to 100 GHz, 500 MHz to 150 GHz, The device is configured to attenuate electromagnetic radiation in the wavelength ranges of 500 MHz to 130 GHz, 500 MHz to 200 GHz, 0.1 MHz to 1 MHz, 1 to 10 MHz, 10 to 100 MHz, 100 to 1000 MHz, 0.1 to 1 GHz, 1 to 150 GHz, 0.1 to 150 GHz, 0.1 to 130 GHz, 1 to 130 GHz, 0.1 to 110 GHz, 1 to 110 GHz, 1 to 5 GHz, 5 to 10 GHz, 1 to 10 GHz, 10 to 20 GHz, 20 to 50 GHz, 50 to 70 GHz, 70 to 90 GHz, 90 to 110 GHz, or any range therebetween. In some embodiments, attenuation of electromagnetic radiation refers to a decrease in the intensity of the electromagnetic radiation compared to a control. In some embodiments, the attenuation is as described above.

[0116] In some embodiments, the articles of the present invention are characterized by an attenuation of electromagnetic radiation of at least 5 dB, at least 10 dB, at least 15 dB, at least 20 dB, or at least 30 dB compared to a control, where the electromagnetic radiation has a wavelength range of 1-150 GHz, 1-120 GHz, 1-130 GHz, 1-110 GHz, or any range therebetween.

[0117] In some embodiments, the articles of the invention have a metric of 2-10, 2-30, 5-10, 5-20, 5-30, 5-40, 6-8, or 8-10 dB·m per gram of article. 2 , or any range therebetween.

[0118] In some embodiments, the walls of the articles of the invention comprise CNTs and surfactants at concentrations ranging from 0.00001 to 2% or 0.00005 to 2%, respectively, and 2 ~At least 10 12 The walls are characterized by surface resistivity in Ω·cm and by EMI attenuation as described herein.

[0119] In some embodiments, the articles of the invention are physically stable. In some embodiments, the stable articles do not substantially undergo phase separation (e.g., collapse of the composite with separation of the CNTs and the polymer matrix). In some embodiments, the stable articles are substantially free of cracking, deformation, or other physical defects. In some embodiments, the stable articles substantially retain their shape, dimensions, and / or physical properties, such as mechanical strength, electrical conductivity, energy dissipation properties, etc.

[0120] In some embodiments, the stable article substantially maintains the properties of the thermoplastic polymer that substantially constitutes the article (e.g., the pure polymer without CNTs and / or surfactants). In some embodiments, the property is a mechanical property selected from tensile strength, Young's modulus, elongation at break, melt strength, or any combination thereof. In some embodiments, the article is characterized by thermoplastic behavior. In some embodiments, the article is characterized by elasticity. In some embodiments, the article is characterized by substantially the same elasticity as the thermoplastic polymer. The term "substantially" as used herein when referring to the properties of the article includes ±1%, ±5%, ±7%, ±10%, ±15%, ±20%, ±30%, or any range therebetween, relative to the properties of the pure polymer.

[0121] In some embodiments, the melting or liquefaction point of the article is substantially the same as the melting point of the thermoplastic polymer.

[0122] In some embodiments, the articles of the present invention are made or shaped by subjecting the compositions of the present invention to conditions suitable for extrusion, injection, hot blown film, molding (e.g., casting, compression molding, rotational molding), or any combination thereof. In some embodiments, the articles of the present invention are made or shaped by subjecting the compositions to any thermoplastic polymer processing method.

[0123] In some embodiments, the compositions of the present invention are manufactured by (i) providing a plurality of particles (also referred to herein as core-shell particles), each particle comprising a polymer core in contact with a shell comprising CNTs and a surfactant, the polymer core comprising a thermoplastic polymer, and the size of the particles being between 30 and 2000 μm, and (ii) subjecting the plurality of particles to a process selected from extrusion, injection, hot blown film, molding (e.g., cast molding, compression molding, rotational molding), or any combination thereof. In some embodiments, the plurality of particles are extrudable particles, and the w / w ratio of the thermoplastic polymer to the CNTs and / or surfactant is as described herein (with respect to the compositions of the present invention). One skilled in the art will appreciate that any thermoplastic polymer can be used in the core-shell particles. Furthermore, the w / w ratio of the CNTs to the thermoplastic polymer in the core-shell particles is predetermined by the desired weight ratio of the CNTs in the compositions / articles of the present invention.

[0124] In some embodiments, the article is substantially stable (e.g., the article substantially maintains its structural and / or functional properties, such as physical stability, and / or lacks degradation or erosion of a coating layer) for at least 1 month (m), at least 2 m, at least 6 m, at least 12 m, at least 2 years (y), at least 3y, at least 10y, or any range therebetween, substantially as described below.

[0125] In some embodiments, the article is substantially stable when exposed to thermal radiation. In some embodiments, the thermal radiation includes temperatures between 30-100° C., −50-0° C., 0-10° C., 10-30° C., 30-50° C., 50-70° C., 70-100° C., 100-150° C., or any range therebetween. In some embodiments, the thermal radiation includes temperatures below the melting point of the thermoplastic polymer.

[0126] The term "stable" as used herein refers to the ability of an article to substantially maintain its structural, physical, and / or chemical properties (including, inter alia, energy attenuation). In some embodiments, an article is said to be stable when it substantially maintains its structure (e.g., shape and / or dimensions such as thickness, length, etc.) and is substantially as described herein.

[0127] In some embodiments, a coating layer is said to be stable when it is substantially free of cracks, deformations, or any other surface irregularities.

[0128] In some embodiments, the terms "coating" and "coating layer" are used interchangeably herein.

[0129] Substrates that can be used in some embodiments of the present invention may have organic or inorganic surfaces, including, but not limited to, glass surfaces, porcelain surfaces, ceramic surfaces, silicone or organosilicon surfaces, metal surfaces (e.g., stainless steel), polymeric surfaces, such as plastic surfaces, rubber-like surfaces, paper, wood, fabrics in woven, knitted or non-woven form, mineral (rock or glass) surfaces, wool, silk, cotton, hemp, leather, plastic surfaces, and surfaces that include or are made of inorganic polymers, such as polymers, polyamides, silicone rubber or glass, or surfaces that include or are made of any of the above materials or any mixtures thereof. Exemplary substrates are selected from, but are not limited to, polymers of polycarbonate, polyester, polyamide, and metal foils, such as aluminum foil.

[0130] In some embodiments, the substrate is in the form of a continuous layer or a woven or non-woven substrate.

[0131] In some embodiments, the article is or includes any one of a gasket, a housing, a casing, grounding, a foam, an enclosure, a box, a tape, a foil, a fiber, a pipe, a jacket, a Faraday cage, an antenna, a display, a radar, an emitting device of one of the following technologies: wireless communication, wi-fi, Bluetooth, 3G (GSM), 4G (LTE), 5G, 6G, WLAN, NFC, RF, cellular, alarm, broadcast communication devices, cable insulation, cable jacketing, electromagnetic noise filters, sensors, compartments and conformal shielding of PCBs, aircraft systems, wearable electronic devices, wearable protective gear, electromagnetic radiation manipulation, e.g., stealth mode, electromagnetic radiation shielding in the form of concealment.

[0132] General As used herein, the term "about" refers to ±10%.

[0133] The terms "comprise," "include," and "have" and their conjugations mean "including, but not limited to."

[0134] The term "consisting of" means "including and limited to."

[0135] The term "consisting essentially of" means that a composition, method, or structure may include additional ingredients, steps, and / or moieties only if the additional ingredients, steps, and / or moieties do not materially alter the basic and novel characteristics of the claimed composition, method, or structure.

[0136] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." An embodiment described as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments and / or to exclude the incorporation of features from other embodiments.

[0137] The word "optionally" is used herein to mean "is provided in some embodiments and is not provided in other embodiments." Any particular embodiment of the present invention may include multiple "optional" features, unless such features are inconsistent.

[0138] The terms "enhance" (enhance) or "reduce" refer to at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 80%, at least 100%, at least 150%, at least 200%, at least 250%, at least 300%, or any range or value therebetween, as compared to a control.

[0139] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" can include a plurality of compounds, including mixtures thereof.

[0140] Throughout this application, various embodiments of the invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as inflexibly limiting the scope of the invention. Thus, the description of a range should be considered to have all possible subranges specifically disclosed, as well as individual numerical values ​​within the range. For example, a description of a range such as "1-6" should be considered to have specifically disclosed subranges such as "1-3", "1-4", "1-5", "2-4", "2-6", "3-6", as well as individual numerical values ​​within the range, e.g., 1, 2, 3, 4, 5, and 6. This is true regardless of the breadth of the range.

[0141] Whenever a numerical range is given herein, it is intended to include any recited numbers (fractional or integer) within the given range. The phrases "range" from a first designator number to a second designator number and "range" from a first designator number to a second designator number are used interchangeably herein and are intended to include the first and second designator numbers and all fractional and integer numbers therebetween.

[0142] The term "substantially" as used herein refers to at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 97%, at least 99%, at least 99.9%, or any range or value therebetween. In some embodiments, the terms "substantially" and "consisting essentially of" are used interchangeably herein.

[0143] The term "method" as used herein refers to manners, means, techniques, and procedures for accomplishing a given task, including, but not limited to, manners, means, techniques, and procedures known or readily developed from known manners, means, techniques, and procedures to practitioners in the fields of chemistry, pharmacology, biology, biochemistry, and medicine.

[0144] The term "treating" as used herein includes halting, substantially inhibiting, slowing, or reversing the progression of the condition, substantially ameliorating the clinical or cosmetic manifestations of the condition, or substantially preventing the onset of the clinical or cosmetic manifestations of the condition.

[0145] It will be appreciated that certain features of the invention that are described for clarity in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features of the invention that are described for brevity in the context of a single embodiment may also be provided separately or in any suitable subcombination or as appropriate in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

[0146] Various embodiments and aspects of the present invention as described hereinabove and as claimed in the claims section below find experimental support in the following examples. Reference is now made to the following examples which, in conjunction with the above description, illustrate certain embodiments of the present invention in a non-limiting manner.

[0147] Working Example Example 1 Exemplary articles of the invention having at least one wall comprised of a composition of the invention were produced by extrusion and / or molding of the core-shell particles described herein.

[0148] To manufacture an exemplary article in the form of a plaque, polyamide (polyamide 6) and SWCNT-based core-shell particles were used. The composition of the core-shell particles is as follows: polyamide (PA6) powder, particle size 30-1300 μm (purchased from LANXESS, DOMO, BASF, etc.); SWCNT 1 wt% (average outer diameter 1.6 nm, length >5 μm, purchased from OCSiAl); Surfactant: polyether copolymer-based surfactant.

[0149] The core-shell particles were prepared as follows: Nylon6 particles were coated with SWCNTs to obtain Nylon6 / CNT core-shell particles with a core to shell w / w ratio of about 100:1 to 10:1. The chemical composition of the exemplary core-shell particles is identical to the composition of the article shown in Table 1 below.

[0150] In an exemplary embodiment, the articles of the present invention were produced by extruding the exemplary core-shell particles in a twin screw extruder (Coperion, ZSK 18 MegaLab, D=18 mm, 48 L / D) under suitable conditions.

[0151] The extrudate was then dried at about 40-100° C. for about 0.5-10 hours.

[0152] The dried extrudates were further shaped (e.g., by compression molding) to obtain 10 cm x 10 cm plaques (approximately 300 μm thick). The EMI attenuation of the exemplary articles was tested as described below and compared to the EMI attenuation of (i) a pure polymer without CNTs, and (ii) a similar article having the same composition but with heterogeneously dispersed CNTs (designated P9-158-1).

[0153] P9-158-1 was prepared by molding (e.g., by compression molding) a mixture composed of polyamide 6 and 0.2% by weight of CNTs to obtain a heterogeneous 10 cm × 10 cm plaque (approximately 300 μm thick).

[0154] The measurements were performed in the laboratory of the Schlesinger Center for Radiation Sources and Applications at Ariel University, Israel. Briefly, the transmit and receive antennas connected to a network analyzer are aligned with each other (see Figure 2). The calibration measurement S21 is performed without a test plate (free field).

[0155] During the measurement, the test plate is introduced into the centre of the radiation field perpendicular to the antennas, so that the centre of the test plate is on an imaginary line between the transmitting and receiving antennas.

[0156] The test piece is aligned at the same height as the electromagnetic wave transmitting antenna and perpendicular to the transmission direction. The transmission characteristics are obtained by measuring the S21 parameter with a network analyzer.

[0157] The results of this experiment are shown in Figure 1A. The values ​​in Figure 1A represent the EMI attenuation relative to the attenuation of a pure polymer. As shown in Figure 1A, over the entire wavelength range tested, the exemplary articles of the present invention exhibited EMI attenuation that was 2-5 orders of magnitude greater than the EMI attenuation of the heterogeneous control.

[0158] Table 1 below shows exemplary compositions of articles of the invention, which exhibit high EMI shielding even at CNT concentrations as low as 0.005-1 wt%.

[0159] Table 1: Composition and EMI attenuation (75-110 GHz) of exemplary articles of the invention [Table 1]

[0160] Pure polymers of substantially the same dimensions as the specimens tested showed negligible attenuation (approximately 0-5 dB).

Claims

1. An article comprising a wall, wherein the wall comprises a polymer matrix and a plurality of CNTs homogeneously dispersed in the polymer matrix, The polymer matrix comprises a thermoplastic polymer with a three-dimensional network structure. The weight ratio of the CNTs to the polymer matrix is ​​0.00001 to 5%. The polymer matrix further comprises a surfactant, An article configured to attenuate electromagnetic radiation in the wavelength range of 1 kHz to 150 GHz.

2. The thermoplastic polymer is at least 10 １０ The article according to claim 1, characterized by a surface resistivity of Ω·cm.

3. The article according to claim 1 or claim 2, wherein aggregated particles of the thermoplastic polymer are not present in the matrix.

4. The article according to claim 1, wherein the wall is characterized by a thickness of 100 nm to 10 mm, and the CNT includes single-walled CNTs (SWCNTs).

5. The weight ratio of the CNT per unit area of ​​the article is 0.05 to 75 g / m² for thicknesses of 40 μm to 1 mm. ２ The article according to claim 1.

6. The article according to claim 1, wherein the w / w ratio of the surfactant to the CNT in the wall is 10:1 to 0.5:

1.

7. The article according to claim 1, wherein the w / w ratio of the surfactant to the polymer in the wall is 0.00001% to 10%.

8. The article according to claim 1, wherein the thermoplastic polymer is characterized by a melting temperature of at least 100°C.

9. The article according to claim 1, further comprising an inorganic material in the form of (i) fibers, (ii) particulate matter, or both.

10. The article according to claim 9, wherein the inorganic material comprises one of glass, metal, mineral, and ceramic, or any combination thereof.

11. The article according to claim 1, wherein the article is in the form of a film.

12. The article according to claim 11, further comprising a further layer in contact with at least one surface of the wall.

13. The article according to claim 12, wherein the further layer comprises a polymer, optionally comprising a high-strength polymer, an inorganic material, or both.

14. The article according to claim 1, wherein the article is bondable to a base material, and the bonding is by physical or chemical adhesion or welding.

15. The article according to claim 1, wherein the attenuation is at least 5 dB when compared to a similar article without CNTs.

16. The article according to claim 15, wherein the attenuation is at least 10 dB in the electromagnetic radiation wavelength range of 1 to 110 GHz.

17. (i) CNT and (ii) surfactant are each present in the wall at a w / w concentration of 0.00001% to 2%, and the article is 10 ２ ~10 １２ The article according to claim 1, characterized by a surface resistivity of Ω·cm.

18. The article according to claim 1, wherein the article is manufactured by a method comprising extrusion, injection molding, hot blow film formation, and molding, or any combination thereof.

19. The article according to claim 1, wherein the wall substantially maintains the properties of a thermoplastic polymer free of surfactants and CNTs, the properties being any of tensile strength, Young's modulus, elongation at break, melt strength, or any combination thereof.

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