JP7122308B2 - Thermoplastic polymer composite containing soft ferromagnetic particulate material and method of making same - Google Patents

Description

The present invention relates generally to polymer composites comprising a thermoplastic polymer network structure and soft ferromagnetic particulate material. Polymer composites can be used, for example, as magnetic flux field directional materials. The present invention also relates to methods of making the polymer composites of the present disclosure.

Various complexes useful for altering magnetic fields have been disclosed in the art. Such conjugates are described, for example, in U.S. Pat. and 2006/0099454 (A1). Additionally, various methods have been disclosed in the art for forming porous polymeric materials. Such conjugates are described, for example, in US Pat. Nos. 5,196,262 and 6,524,742(B1).

In one aspect, the present disclosure is a polymer composite comprising a thermoplastic polymer network structure and a soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure, wherein the soft ferromagnetic particulate material is 0.80 to 0.98, based on the total weight of the polymer composite, and the thermoplastic polymer has a number average molecular weight of 5×10 ⁴ g/mol to 5×10 ⁷ g/mol A polymer composite is provided.

In another aspect, the present disclosure is a method of making a polymer composite sheet having a first major surface, wherein (i) it has a number average molecular weight of from 5×10 ⁴ g/mol to 5×10 ⁷ g/mol; providing a thermoplastic polymer, a solvent in which the thermoplastic polymer is soluble, and a soft ferromagnetic particulate material; and (ii) mixing the thermoplastic polymer, the solvent and the soft ferromagnetic particulate material to form a soft ferromagnetic particulate material. (iii) forming the thermoplastic polymer solvent solution containing the soft ferromagnetic particles into a sheet; (iv) separating a phase of the thermoplastic polymer from the solvent (v) removing at least a portion of the solvent, thereby having a thermoplastic polymer network structure and a soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure; A method is provided comprising forming a composite sheet, wherein the weight fraction of the soft ferromagnetic particulate material is between 0.80 and 0.98, based on the total weight of the polymer composite sheet.

Optionally, the method further comprises applying vibrational energy to the polymer composite sheet concurrently with applying the compressive force. Preferably, the vibrational energy is ultrasonic energy.

The foregoing has summarized various aspects and advantages of exemplary embodiments of the present disclosure. The above Summary of the Invention is not intended to describe each illustrated embodiment or every implementation of the specific exemplary embodiments of the present disclosure. The following drawings and Detailed Description more particularly exemplify certain preferred embodiments employing the principles disclosed herein.

A more complete understanding of the present disclosure can be obtained by considering the following detailed description of various embodiments of the disclosure in conjunction with the accompanying drawings.
FIG. 4 shows an SEM image of an exemplary polymer composite cross-section according to an exemplary embodiment of the present disclosure; FIG. 2 shows an SEM image of the exemplary polymer composite cross-section of FIG. 1 after the polymer composite has been densified, according to an exemplary embodiment of the present disclosure; Repeat use of reference characters in the specification and drawings is intended to represent same or analogous features or elements of the disclosure. Drawings may not be drawn to scale.

It should be understood that many other modifications and embodiments could be devised by those skilled in the art and still fall within the spirit and scope of the principles of the present disclosure. All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified. The definitions provided herein are to aid understanding of certain terms frequently used herein and are not intended to limit the scope of the disclosure.

With respect to the glossary of defined terms below, these definitions shall apply throughout this application unless a different definition is provided in the claims or elsewhere in the specification.

Glossary The term "close to" with respect to a particular layer means that the two layers are adjacent (i.e., adjacent) and in direct contact with each other, or in close proximity but not in direct contact (i.e., adjacent to each other). That is, it is joined to or attached to another layer at a location where one or more additional layers are interposed between those layers.

Orientation terms such as "atop", "on", "over", " relative to an element placed horizontally and facing upwards by using "covering", "uppermost", "underlying", etc. Mention location. However, unless otherwise indicated, it is not intended that the substrate or article should have any particular spatial orientation during or after manufacture.

By using the term "overcoated" to describe the position of a layer relative to the substrate or other element of the articles of this disclosure, the layer is placed on the substrate or other element. It refers to there being, but not necessarily in close proximity to the substrate or other element.

By using the term "separated by" to describe the position of a layer relative to other layers, the layer is located between two other layers, but not necessarily either. It refers to not being contiguous or contiguous with the layer.

The term "about" or "approximately" in reference to a number or shape means ±5 percent of the number or property or characteristic, but expressly includes the exact number. For example, a viscosity of “about” 1 Pa·sec refers to a viscosity of 0.95 to 1.05 Pa·sec, but expressly includes a viscosity of exactly 1 Pa·sec. Similarly, a "substantially square" perimeter is defined as four lateral edges with each lateral edge having a length that is 95% to 105% of the length of any other lateral edge. Although we intend to describe geometries that have edges, this is also meant to include geometries in which each lateral edge has exactly the same length. Unless otherwise indicated, all numbers expressing amounts or ingredients, measurements of properties, etc. used in the specification and embodiments are to be understood as being modified in all instances by the term "about." do.

The term "substantially" with respect to a property or characteristic means that the property or characteristic is exhibited to a greater degree than the opposite of that property or characteristic is exhibited. For example, a "substantially" transparent substrate refers to a substrate that transmits more radiation (eg, visible light) than it does not transmit (eg, absorbs and reflects). Therefore, a substrate that transmits more than 50% of the visible light incident on its surface is substantially transparent, but transmits less than 50% of the visible light incident on its surface. The substrate is substantially non-transparent.

As used in this specification and the accompanying embodiments, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to a fine fiber containing "a compound" includes mixtures of two or more compounds. As used in this specification and the accompanying embodiments, the term "or" is generally used in its sense to include "and/or" unless the content clearly dictates otherwise.

Throughout this specification, references to "one embodiment," "particular embodiment," "one or more embodiments," or "an embodiment" are preceded by the term "embodiment." A specific feature, structure, material, or feature described in connection with that embodiment may be the is meant to be included in at least one embodiment thereof. Thus, in various places throughout this specification the appearances of phrases such as "in one or more embodiments," "in certain embodiments," "in one embodiment," or "in an embodiment" , do not necessarily refer to the same one of the specific exemplary embodiments of this disclosure. Moreover, the specific features, structures, materials, or properties may be combined in any suitable manner in one or more embodiments.

Exemplary embodiments of the disclosure may take on various modifications and alterations without departing from the spirit and scope of the disclosure. Accordingly, embodiments of the present disclosure are not limited to the exemplary embodiments described below, but are to be governed by the limitations set forth in the claims and any equivalents thereof. It should be understood that there is

Description of Problem to be Solved New and improved e.g. wireless charging for various electronic devices including but not limited to mobile/handheld devices such as phones, tablets, video games, laptop computers There is a constant demand for the inclusion of optimized functionality. As the demand for additional functionality in these portable electronic devices grows, the available space within such devices decreases due to the corresponding components. Moreover, these new and improved features also place increased demands on the battery capacity required to power these devices. As a result, there is an increasing need for higher wireless charging (WPC) capabilities.

Wireless charging is one of the recent additions to mobile/handheld devices. One typical requirement for WPCs is the need to concentrate and/or direct the magnetic field to specific locations within the electronic device, while shielding other areas from the magnetic field. Flux Field Directive Materials (FFDM) can be used for this purpose. The FFDM can direct the magnetic flux density through itself and through the WPC device's receiver coil, thereby preventing it from reaching nearby metal parts such as the battery case. As the power demand for recharging the batteries of electronic devices increases, eg, higher power and higher power transfer rate requirements, FFDMs need to be able to focus and redirect increasing amounts of magnetic flux.

Due to the large number of electronic device designs, the FFDM also needs to be easily configured to fit the desired space within the device. Flexible materials are desirable in this respect. However, the most commonly used current ferrite sheet FDDM materials tend to be rigid and inflexible.

In addition, amorphous or nanocrystalline ribbons (nanoribbons) have the ability to redirect high magnetic flux densities, but are expensive to incorporate into consumer electronics. They are also limited to low frequency applications due to their relatively high electrical conductivity and the consequent induced eddy current losses. Ferrite sheets are limited to relatively low saturation magnetic flux densities and are very difficult to shape, process or handle without breakage during manufacturing. Therefore, it is preferable to use conventional composite materials for wireless power transfer. However, due to processing limitations, the maximum loading of magnetic flakes required in current composite materials is only about 50 volume percent, limiting their usefulness in high power transmission applications.

Also, the processes currently used to manufacture composite materials result in more expensive materials compared to, for example, ferrite. Despite the cost penalty, composite materials are utilized for some FDDM applications at low power transmission rates (approximately 5 W). However, these materials have limited ability to localize and redirect the high magnetic flux densities required for high power transfer rates (15 W and above) in next generation devices. Furthermore, as the WPC protocol involves higher frequencies, possibly above 1 MHz, FFDM needs to meet stringent material requirements, such as lower resistivity, that are not achieved with current composite materials. Overall, there is a need for improved FDDM materials that enable at least one of improved forming properties (eg, improved flexibility), increased power transfer levels, and lower cost.

Various exemplary embodiments of the present disclosure are described below with specific reference to the drawings. Various modifications and changes may be made to the exemplary embodiments of the disclosure without departing from the spirit and scope of the disclosure. Accordingly, embodiments of the present disclosure are not limited to the exemplary embodiments described below, but are to be governed by the limitations set forth in the claims and any equivalents thereof. It should be understood that there is

Accordingly, in one exemplary embodiment, the present disclosure provides unique polymer composites that can serve, for example, as FDDMs with improved performance. The polymer composites of the present disclosure comprise a thermoplastic polymer network structure and a soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure.

A unique method for the production of polymer composites involving induced phase separation of a thermoplastic polymer solvent mixture containing soft ferromagnetic particle material is that the network structure of the thermoplastic polymer formed during the production process allows the soft ferromagnetic particle material Very high loadings of (up to about 80 volume percent) and low polymer content in polymer composites (up to about 4 weight percent) are possible. As a result, by using about 100 micrometer thick films of this polymer composite, a high saturation magnetic flux density, for example, 0.67 T, can be achieved, and these polymer composites enable high power output of electronic devices. It is possible to improve wireless charging capabilities. The unique structure of the composite, including the network structure of the thermoplastic polymer, also enables improved flexibility and forming properties of the polymer composites of the present disclosure.

In one embodiment, the present disclosure is a polymer composite comprising a thermoplastic polymer network structure and a soft ferromagnetic particle material dispersed within the thermoplastic polymer network structure, wherein the soft ferromagnetic particles The weight fraction of the material is from 0.80 to 0.98, based ^on the ^total weight of the polymer composite, and the thermoplastic has a number average A polymer conjugate is provided having a molecular weight. The network structure of thermoplastic polymers can be viewed as a three-dimensional network structure.

The network structure of thermoplastic polymers is porous in nature and can have a continuous porous network structure. In some embodiments, at least a portion of the thermoplastic polymer network structure is a continuous thermoplastic polymer network structure. In some embodiments, the entire network structure of the thermoplastic polymer is continuous It is a network structure of a thermoplastic polymer.

Note that the portion of the polymer composite volume associated with the soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure is not considered part of the thermoplastic polymer network structure. In some embodiments, the soft ferromagnetic particulate material is uniformly dispersed within the network structure of the thermoplastic polymer. In some embodiments, when the soft ferromagnetic particle material is an anisotropic soft ferromagnetic particle material, the anisotropic soft ferromagnetic particle material can be randomly dispersed within the network structure of the thermoplastic polymer. By "random" is meant no orientation of the particulate material with respect to its anisotropy. In some embodiments, when the soft ferromagnetic particle material is an anisotropic soft ferromagnetic particle material, the anisotropic soft ferromagnetic particle material can be uniformly and randomly dispersed within the network structure of the thermoplastic polymer. .

In some embodiments, when the soft ferromagnetic particle material is an anisotropic soft ferromagnetic particle material, the anisotropic soft ferromagnetic particle material is a network of thermoplastic polymers It can be dispersed so as to be oriented within the structure. In some embodiments, when the soft ferromagnetic particle material is an anisotropic soft ferromagnetic particle material, the anisotropic soft ferromagnetic particle material is a network of thermoplastic polymers It can be distributed uniformly so as to be oriented within the structure.

Referring now to the drawings, FIG. 1 shows a cross-sectional SEM micrograph of an exemplary polymer composite of the present disclosure. The polymer composite of FIG. 1 comprises flake-shaped soft ferromagnetic particulate materials having length dimensions in the range of about 30 micrometers to about 100 micrometers and overall thicknesses of about 1 micrometer to about 5 micrometers. include. The length dimension of the flakes is generally parallel to the top surface of the polymer composite. Since the images are cross-sectional, the flakes appear as needle-like objects running generally parallel to each other. The network structure of thermoplastic polymers is observed between flakes, comprising a plurality of interconnected thermoplastic fibrils.

In this exemplary embodiment, the thermoplastic fibrils generally have a length of about 5 micrometers to about 15 micrometers and a thickness of generally about 1 micrometer to about 3 micrometers; That is, it has a width. Based on the process used to make the polymer composite of FIG. is a continuous thermoplastic polymer network structure.

In some embodiments, the thermoplastic polymer network structure comprises a plurality of interconnected thermoplastic fibrils. The interconnected thermoplastic fibrils can adhere directly to the surface of the soft ferromagnetic particle material and act as a binder for the soft ferromagnetic particle material. Thus, in some embodiments, the thermoplastic polymer network structure is the binder for the soft ferromagnetic particulate material.

While not wishing to be bound by theory, it is believed that the formation of a thermoplastic polymer network structure is soft and strong compared to conventional composite materials, i.e., composites without a thermoplastic polymer network structure. It is believed to allow for higher mass/volume loadings of magnetic particle material while providing improved flexibility to the polymer composites of the present disclosure. Surprisingly, this unique structure provides better handling properties in end-use applications, possibly due to the increased flexible nature of the network structure of the thermoplastic polymer, as well as presumably within the polymer composite. The performance as a magnetic FFDM is improved due to the ability to obtain a high loading of the soft ferromagnetic particle material of .

To enhance the magnetic FFDM properties of the polymer composites of the present disclosure, it is desirable to increase the amount of soft ferromagnetic particle material in the polymer composites. In some embodiments, the weight fraction of soft ferromagnetic particulate material is 0.80 to 0.98, 0.85 to 0.97, or even 0.90 to 0.97, based on the total weight of the polymer composite. .96. In some embodiments, the volume fraction of the soft ferromagnetic particulate material is 0.10-0.80, 0.20-0.80, 0.30-0.30, based on the total volume of the polymer composite. 80, 0.10-0.75, 0.20-0.75, 0.30-0.75, 0.10-0.70, 0.20-0.70 or even 0.30-0. can be 70;

Furthermore, it is desirable to have a high density of polymer composites to enhance the magnetic FFDM properties of the polymer composites of the present disclosure. Increasing the density of the polymer composite includes, but is not limited to, using a higher density of soft ferromagnetic particulate material, using a higher weight fraction of soft ferromagnetic particulate material in the polymer composite. and/or densifying a portion of the network structure of the thermoplastic polymer of the polymer composite.

The network structure of the thermoplastic polymer of the polymer composites of the present disclosure can be disrupted by applying at least one of compressive or tensile forces, thereby densifying the polymer composite. As such, the unique structure of the polymer composites of the present disclosure provides an alternative means of densifying polymer composites that cannot be used in conventional composites. The densification process can achieve high densities, but may be carried out at a temperature capable of causing plastic deformation of the thermoplastic polymer of the network structure of the thermoplastic polymer, whereby the heat It is possible to leave a small part of the network structure of the plastic polymer.

This process results in a high density polymer with enhanced FFDM properties (compared to non-collapsed polymer composites) while still maintaining improved handling properties associated with the flexibility of the network structure of the thermoplastic polymer. material is obtained. In general, collapsing the network structure of a thermoplastic polymer at temperatures at which the network structure of the thermoplastic polymer melts is undesirable as it can result in loss of the network structure of the thermoplastic polymer. In some embodiments, the polymer composite is not exposed to temperatures above the glass transition temperature of the thermoplastic polymer.

In some embodiments, the polymer composite is not exposed to temperatures above the melting temperature of the thermoplastic polymer. In some embodiments, when two or more thermoplastic polymers are used for the thermoplastic polymer, the polymer composite is not exposed to temperatures above the highest glass transition temperature of the thermoplastic polymer. In some embodiments, when two or more thermoplastic polymers are used for the thermoplastic polymer, the polymer composite is not exposed to temperatures above the maximum melting temperature of the thermoplastic polymers.

FIG. 2 shows a cross-sectional SEM image of the exemplary polymer composite of FIG. 1 after the network structure of the thermoplastic polymer has collapsed. Compared to FIG. 1, the polymer composite is densified and the soft ferromagnetic particles (soft ferromagnetic particle flake material of the present embodiment) are compressed together. The spacing between flakes is significantly reduced.

Compared to Figure 1, the network structure of the thermoplastic polymer in Figure 2 was significantly reduced as the network structure of the thermoplastic polymer collapsed upon application of compressive force. The application of compressive force was performed at a temperature at which plastic deformation of the network structure of the thermoplastic polymer occurred. In FIG. 2, a dense polymer composite has been formed, but small regions of the thermoplastic polymer network structure are still discernible.

In some embodiments, the network structure of the thermoplastic polymer can be plastically deformed. In some embodiments, the network structure of the thermoplastic polymer can be plastically deformed by at least one of compressive and tensile forces. In some embodiments, the network structure of thermoplastic polymers can be plastically deformed by compressive forces alone. In some embodiments, the network structure of the thermoplastic polymer can be plastically deformed by tensile forces alone.

The flexibility of polymer composites is measured by various techniques such as flexural modulus testing or the ability of a polymer composite sheet to bend around a cylindrical object having a given radius, i.e. a given radius of curvature. can be determined by examining In some embodiments, when the polymer composite is in the form of a sheet having a thickness of 20 micrometers to 300 micrometers, the polymer composite forms a radius of curvature of 10 mm, 5 mm or even 3 mm. can bend. In some embodiments, when the polymer composite is in the form of a sheet having a thickness of 150 micrometers, the polymer composite can bend to form a radius of curvature of 10 mm, 5 mm or even 3 mm. .

In some embodiments in which the network structure is plastically deformed by at least a compressive force, vibrational energy may be imparted when the compressive force is applied. In some of these embodiments, the polymer composite sheet is in the form of a strip of indeterminate (arbitrary) length and the step of applying a compressive force is performed as the strip passes through the nip. A tensile load may be applied as it passes through such a nip.

For example, a nip can be between two rolls (at least one of which applies vibrational energy), between a roll and a bar (at least one of which applies vibrational energy), or between two bars. (at least one of which applies vibrational energy). Application of compressive force and vibrational energy can be accomplished in a continuous roll-to-roll or step-and-repeat fashion.

In certain embodiments, the step of applying the compressive force comprises separate sheets of limited length, e.g., positioned between a plate and a platen, at least one of which applies vibrational energy. is carried out against

In some embodiments, the vibrational energy is in the ultrasonic range, eg, 20 kHz, although other ranges are also considered suitable. Particle fractions greater than 52% by volume can be achieved while still obtaining excellent magnetic properties when utilizing vibrational energy during the application of a compressive force. Polymer composite sheets with a coercivity of 240 A/m or less, or even 200 A/m or less can be obtained.

When the polymer composite is in the form of a sheet having a first major surface and the soft ferromagnetic particles have an aspect ratio of at least 1, i.e. greater than 1, based on the length dimension/thickness dimension (particles that are anisotropic with respect to shape, e.g. flakes), deformation of the network structure of the thermoplastic polymer, e.g. can be oriented

By aligning or orienting the length dimension of the anisotropic soft ferromagnetic particles with respect to the first major surface of the polymer composite sheet, the FFDM properties of the polymer composite can be improved. In some embodiments, the polymer composite is in the form of a sheet having a first major surface, the soft ferromagnetic particle material is a soft ferromagnetic particle flake material, each flake having a first major surface, and a thickness perpendicular to the first major surface of the flakes, such that a majority of the first major surfaces of the flakes are within at least 25 degrees of the first major surface of the adjacent polymer composite sheet. is oriented to

By "majority" is meant that at least 50 percent of the first major surface of the flakes are oriented within at least 25 degrees of the first major surface of the adjacent polymer composite sheet. do. In some embodiments, at least 30 percent, at least 50 percent, at least 70 percent, at least 80 percent, at least 90 percent, at least 95 percent, at least 98 percent, or even 100 percent of the first major surface of the flakes are Oriented within at least 25 degrees, at least 20 degrees, at least 15 degrees, or even at least a further 10 degrees relative to the first major surface of the adjacent polymer composite sheet.

In some embodiments, the polymer composite is in the form of a sheet having a first major surface and a thickness of 20 microns to 5000 microns, and the soft ferromagnetic particle material is a soft ferromagnetic particle flake material. and each flake has a first major surface and a thickness perpendicular to the first major surface of the flake, the majority of the first major surface of the flake being the first major surface of the adjacent polymer composite sheet. It is oriented within at least 25 degrees with respect to one major surface.

The density of the polymer composite can vary depending on the density and amount of soft ferromagnetic particulate material used, the density of the thermoplastic polymer, and the porosity of the network structure of the thermoplastic polymer. In general, the higher the density, the greater the magnetic properties, eg, FFDM properties, of the polymer composite.

In some embodiments, the density of the polymer composite is 1.5 g/cm ³ to 6 g/cm ³ , 1.5 g/cm ³ to 5.5 g/cm ³ , 1.5 g/cm ³ , 3.0 g /cm ³ , 1.5 g/cm ³ to 2.5 g/cm ³ , 3.0 g/cm ³ to 6.0 g/cm ³ , 3.0 g/cm ³ to 5.5 g/cm ³ , 3.0 g/cm 3 cm ³ to 5.0 g/cm ³ , 3.5 g/cm ³ to 6.0 g/cm ³ , 3.5 g/cm ³ to 5.5 g/cm ³ or even 3.5 g/cm ³ to 5.0 g / ^cm3 .

The thickness of the polymer composite, for example, the thickness of the polymer composite sheet is not particularly limited. However, in many applications, e.g. mobile/handheld electronics, the thickness of the polymer composite, e.g. and desirably greater than 20 micrometers, greater than 40 micrometers or even greater than 60 micrometers.

In some embodiments, the thickness of the polymer composite, eg, the thickness of the polymer composite sheet, is 20 micrometers to 5000 micrometers, 20 micrometers to 3000 micrometers, 20 micrometers to 1000 micrometers, 20 micrometers to 500 micrometers, 20 micrometers to 300 micrometers, 40 micrometers to 5000 micrometers, 40 micrometers to 3000 micrometers, 40 micrometers to 1000 micrometers, 40 micrometers to 500 micrometers, 40 micrometers ~300 microns, 60 microns to 5000 microns, 60 microns to 3000 microns, 60 microns to 1000 microns, 60 microns to 500 microns or even 60 microns to 300 microns.

Aspects of the polymer composite that affect the magnetic properties of the polymer composite include the type and amount of soft ferromagnetic particle material used in the polymer composite, the particle shape, e.g., flakes, and the orientation of the particles (shape anisotropy if it is sexual), but is not limited to these. Orientation of the first major surface of the flakes of the soft ferromagnetic particle flake material with respect to the first major surface of the polymer composite sheet can result in enhanced magnetic properties of the polymer composite sheet.

"Oriented" means that the first major surface of the flakes is aligned with the first major surface of the composite sheet. Perfect alignment, ie, perfect orientation, is when the first major surface of the flake is parallel to the first major surface of the polymer composite sheet, i.e., the first major surface of the flake and the first major surface of the polymer composite. This is the case where the angle between the first main surface is 0 degrees.

In some embodiments, the polymer conjugate has a magnetic saturation induction of 600-1000 mT, 600-900 mT, 700-100 mT or even 700-900 mT.

In electromagnetism, the ability of a material to support the formation of a magnetic field within it is called the magnetic permeability μ, which describes the extent to which the material can be magnetized in response to an applied magnetic field. Relative permeability is the ratio of the permeability μ of a material to the permeability μ _o of free space, ie a vacuum. The free space permeability μ _o can be defined as 1.257×10 ⁻⁶ H/m.

In some embodiments, the relative permeability magnitude μ/μ _o of the polymer composites of the present disclosure at a frequency of 1 MHz can be greater than 70, greater than 150, or even greater than 500. In some embodiments, the magnitude of relative permeability is greater than 70, greater than 150, or even greater than 500 at frequencies between 50 MHz and 1000 MHz. In some embodiments, the magnitude of relative permeability is greater than 70, greater than 150, or even greater than 500 at frequencies between 50 MHz and 300 MHz.

A polymer composite comprises a thermoplastic polymer formed into a network structure of thermoplastic polymers. The thermoplastic polymer is not particularly limited. Thus, in some embodiments, thermoplastic polymers include polyurethanes, polyesters (such as polyethylene terephthalate, polybutylene terephthalate and polylactic acid), polyamides (such as nylon 6, nylon 6,6 and polypeptides), polyethers. (polyethylene oxides and polypropylene oxides), polycarbonates (bisphenol-A-polycarbonates), polyimides, polysulfones, polyphenylene oxides, polyacrylates (e.g. thermoplastic polymers formed from the addition polymerization of monomers containing acrylate functional groups), polymethacrylates (e.g. thermoplastic polymers formed from the addition polymerization of monomers containing methacrylate functional groups), polyolefins (polyethylene and polypropylene), styrene and styrenic random and block copolymers, chlorinated polymers (polyvinyl chloride), fluorinated Polymers (polyvinylidene fluoride; copolymers of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride; copolymers of ethylene, tetrafluoroethylene and hexafluoropropylene; and polytetrafluoroethylene) and copolymers of ethylene and chlorotrifluoroethylene include, but are not limited to, at least one of

Thermoplastic polymers may be at least one of homopolymers and copolymers (eg, block copolymers or random copolymers). In some embodiments, the thermoplastic polymer is a mixture of two or more thermoplastic polymers, such as a mixture of polyethylene and polypropylene or a mixture of polyethylene and polyacrylate. In some embodiments, the polymer is selected from polyethylene (eg, ultra-high molecular weight polyethylene), polypropylene (eg, ultra-high molecular weight polypropylene), polylactic acid, poly(ethylene-co-chlorotrifluoroethylene), and polyvinylidene fluoride. may be at least one of In some embodiments, the thermoplastic polymer is a single thermoplastic polymer, i.e. not a mixture of two or more thermoplastic polymers.

The molecular weight of the thermoplastic polymer is not particularly limited, except that it must be of sufficient molecular weight to be able to phase separate from the solvent and result in the formation of a network structure. Generally, the number average molecular weight of the thermoplastic polymer may need to be higher than 5 x ¹⁰⁴ g/mole. In some embodiments, the thermoplastic polymer has a number average molecular weight of 5×10 ⁴ g/mol to 5×10 ⁷ g/mol, 5×10 ⁴ g/mol to 1×10 ⁷ g/mol, 5×10 7 g/mol, 10 ⁴ g/mol to 5×10 ⁶ g/mol, 1×10 ⁵ g/mol to 1×10 ⁷ g/mol, 1×10 ⁵ g/mol to 5×10 ⁶ g/mol, 1×10 ⁶ g/mol to 1×10 ⁷ g/mol, 3×10 ⁶ g/mol to 1×10 ⁷ g/mol, 5×10 ⁶ g/mol to 1×10 ⁷ g/mol, 1×10 ⁶ g/mol mol to 5×10 ⁷ g/mol, 3×10 ⁶ g/mol to 5×10 ⁷ g/mol, 5×10 ⁶ g/mol to 5×10 ⁷ g/mol or even 1×10 ⁶ g/mol mol to 5×10 ⁶ g/mol.

Thermoplastic polymers with ultra high molecular weights can be particularly useful. In some embodiments, ultrahigh molecular weight is defined as a thermoplastic polymer having a number average molecular weight of at least 3×10 ⁶ g/mole. Number average molecular weight can be measured by techniques known in the art, including, but not limited to, gel permeation chromatography (GPC). GPC can be performed with the use of narrow molecular weight distribution polymer standards, such as narrow molecular weight distribution polystyrene standards, in a good solvent for thermoplastic polymers.

Thermoplastic polymers are generally characterized as partially crystalline and exhibit a melting point. In some embodiments, the thermoplastic polymer has a melting point between 120°C and 350°C, between 120°C and 300°C, between 120°C and 250°C, or even between 120°C and 200°C. The melting point of thermoplastic polymers can be measured by techniques known in the art, including using a 5 mg to 10 mg sample and heating at a rate of 10° C./min while the sample is under a nitrogen atmosphere. Examples include, but are not limited to, measuring the onset temperature in a Differential Scanning Calorimetry (DSC) test performed at kinetics.

The thermoplastic polymer of the polymer composite is prepared by mixing the thermoplastic polymer with a suitable solvent to form a miscible thermoplastic polymer solvent solution, followed by phase separation of the thermoplastic polymer from the solvent, and then removing at least a portion of the solvent to form a network structure of the thermoplastic polymer through the process. This process is typically carried out by adding the soft ferromagnetic particulate material to a miscible polymer solvent solution prior to phase separation. A network structure of thermoplastic polymers can be formed during the phase separation step of the process. In some embodiments, the thermoplastic polymer network structure is produced by induced phase separation of a miscible thermoplastic polymer solvent solution.

The network structure of thermoplastic polymers is inherently porous, ie contains pores. The pores may be continuous, thereby providing fluid communication from the inner region of the thermoplastic polymer network structure to the surface of the thermoplastic polymer network structure and/or the first surface of the thermoplastic polymer network structure. and a second surface opposite the network structure of the thermoplastic polymer.

The pore size of the network structure of the thermoplastic polymer is not particularly limited. In some embodiments, the pore size is on the micrometer scale, ie, between about 1 micrometer and 1000 micrometers. In some embodiments, the pore size is on the nanometer scale, ie, between about 10 nanometers and 1000 nanometers.

In some embodiments, the average pore size or median pore size P of the network structure of the thermoplastic polymer is between 10 nanometers and 1000 micrometers, ~100 micrometers, 10 nanometers to 50 micrometers, 10 nanometers to 25 micrometers, 100 nanometers to 1000 micrometers, 50 nanometers to 1000 micrometers, 50 nanometers to 500 micrometers, 50 nanometers to 250 micrometers micrometers, 50 nanometers to 100 micrometers, 50 nanometers to 50 micrometers, 50 nanometers to 25 micrometers, 100 nanometers to 1000 micrometers, 100 nanometers to 500 micrometers, 100 nanometers to 250 micrometers , 100 nanometers-100 micrometers, 100 nanometers-50 micrometers, 100 nanometers-25 micrometers, 250 nanometers-1000 micrometers, 250 nanometers-500 micrometers, 250 nanometers-250 micrometers, 250 Nanometer to 100 micrometers, 250 nanometers to 50 micrometers or even 250 nanometers to 25 micrometers.

Using cross-sectional imaging (e.g., light microscopy, scanning electron microscopy, or atomic force microscopy) and appropriate software, such as ImageJ software (e.g., open source software available online at http://imagej.net) Pore sizes and pore size distributions can be statistically analyzed using conventional pore size analysis techniques, including image analysis. Pore size and/or pore size distribution can also be analyzed using X-ray microtomography and mercury porosimetry, bubble point and capillary flow porosimetry.

The continuous nature of the pores of the thermoplastic polymer network structure can facilitate solvent removal from the thermoplastic polymer network structure. In the present disclosure, the term "thermoplastic polymer network structure" means that at least a portion of the pores of the thermoplastic polymer network structure are free of liquids and solids and contain one or more gases, such as, for example, air. essentially means. In some embodiments, 10 volume percent to 100 volume percent, 30 volume percent to 100 volume percent, 50 volume percent to 100 volume percent, 60 volume percent to 100 volume percent, 70 volume percent of the pores of the thermoplastic polymer network structure percent to 100 percent by volume, 80 percent to 100 percent by volume, 90 percent to 100 percent by volume, 95 percent to 100 percent by volume, or even 98 percent to 100 percent by volume excludes liquids and solids, such as , contains one or more gases such as air.

To form a miscible thermoplastic polymer solvent solution, the solvent is required to dissolve the thermoplastic polymer. A solvent for a particular thermoplastic polymer is therefore selected based on this requirement. The thermoplastic polymer solvent mixture may be heated to facilitate dissolution of the thermoplastic polymer in the solvent. Techniques known in the art including phase separation of the thermoplastic polymer from the solvent followed by evaporation of the solvent or extraction of the solvent with a second solvent having a lower vapor pressure followed by evaporation of the second solvent. is used to remove at least a portion of the solvent from the network structure of the thermoplastic polymer.

In some embodiments, at least 10 weight percent to 100 weight percent, at least 30 weight percent to 100 weight percent, at least 50 weight percent to 100 weight percent, at least 60 weight percent to 100 weight percent, at least 70 weight percent to 100 weight percent percent, at least 80 weight percent to 100 weight percent, at least 90 weight percent to 100 weight percent, at least 95 weight percent to 100 weight percent, or even at least 98 weight percent to 100 weight percent of the solvent and the second solvent (used case) is removed from the network structure of the thermoplastic polymer.

The polymer composites of the present disclosure include soft ferromagnetic particulate material. "Soft" when describing ferromagnetic particulate materials has its conventional meaning in the art, non-magnetic particulate materials exhibiting a magnetic field when placed in a magnetic field, e.g., a weak magnetic field. about the ability to take on The induced magnetism of the soft ferromagnetic particle material substantially disappears when the magnetic field is removed. That is, the material exhibits reversible magnetism in an applied magnetic field.

In some embodiments, the coercivity of the soft magnetic particle material is 1 A/m to 1000 A/m, 10 A/m to 1000 A/m or even 30 A/m to 1000 A/m. In some embodiments, the coercivity of the soft magnetic particle material is 1000 A/m or less. Soft ferromagnetic grain materials can have narrow hysteresis loops, i.e., low values of coercivity Hc, high magnetic saturation induction, high magnetic permeability, and for high frequency applications, low It is desirable to have electrical conductivity.

In some embodiments, the soft ferromagnetic particle material is Fe—Cr alloy, Fe—Si alloy (Fe—Si, commercially available from Tianjin Ecotech Trade Co., Ltd. (Tianjin, China) under the trade name SENDUST -Al, and Fe--Si--Cr), FeCoB, Fe-based amorphous alloys, nanocrystalline Fe-based oxides and nanocrystalline Fe-based nitrides. iron, but not limited to; nickel-based alloys, including but not limited to Ni--Fe alloys and Ni--Si alloys; CoNbZr; and boron-based amorphous alloys.

The shape of the soft ferromagnetic particle material is not particularly limited, but flake-like particles can be particularly beneficial. The flakes are irregularly shaped flakes having a first major surface and a second major surface and a thickness substantially perpendicular to at least one of the first major surface and the second major surface. It can be regarded as a plate-like structure. In some embodiments, the soft ferromagnetic particle material is a soft ferromagnetic particle flake material, each flake having a first major surface, a maximum thickness T perpendicular to the first major surface of the flake, have

Flakes of soft ferromagnetic particle flake material can be characterized by a median diameter D50 (with respect to the length dimension L) and a maximum thickness T. In some embodiments, the soft ferromagnetic particle material can be an anisotropic soft ferromagnetic particle material. The aspect ratio of an anisotropic soft ferromagnetic grain is defined as the median diameter D50, e.g. determined by particle size analysis, divided by the maximum thickness of the anisotropic grain, e.g. determined by image analysis. can be done.

For a particular group of soft ferromagnetic grain materials, the maximum thickness value can be the median value Tm. The ratio D50/Tm is the median aspect ratio. In some embodiments, the median aspect ratio D50/Tm is 5/1 to 1000/1, 10/1 to 1000/1, 20/1 to 1000/1, 5/1 to 500/1, 10/1 and ~500/1, 20/1 to 500/1, 5/1 to 200/1, 10/1 to 200/1 or even 20/1 to 200/1.

In some embodiments, the flake image length Li observed and measured in the cross-sectional image of the polymer composite can be the length of the flake, and the flake image observed and measured in the cross-sectional image of the polymer composite. The thickness Ti can be taken as the maximum thickness of the flakes. The image may be, for example, an optical micrograph or SEM. For a particular group of soft ferromagnetic particle flake materials, the values of Li and Ti are derived from the average Lia (average image length) and Tia (average image thickness) of a subset of flakes using standard statistical analysis methods. ). In some embodiments, Lia/Tia is 5/1 to 1000/1, 10/1 to 1000/1, 20/1 to 1000/1, 5/1 to 500/1, 10/1 to 500/1 1, 20/1 to 500/1, 5/1 to 200/1, 10/1 to 200/1 or even 20/1 to 200/1.

In some embodiments, D50 is 5 micrometers to 5000 micrometers, 5 micrometers to 1000 micrometers, 5 micrometers to 500 micrometers, 5 micrometers to 200 micrometers, 10 micrometers to 5000 micrometers, 10 microns to 1000 microns, 10 microns to 500 microns, 10 microns to 200 microns, 25 microns to 5000 microns, 25 microns to 1000 microns, 25 microns to 500 microns or even 25 micrometers to 200 micrometers.

In some embodiments, the flakes of the soft ferromagnetic particle flake material have a median diameter D50 and the thermoplastic polymer network structure has an average pore size P, where D50>2P. In some embodiments, D50 is between 25 micrometers and 5000 micrometers, P is between 50 nanometers and 25 micrometers, and D50>2P. In some embodiments, D50 is between 10 micrometers and 5000 micrometers, P is between 50 nanometers and 25 micrometers, and D50>2P. In some embodiments, D50 is between 25 micrometers and 5000 micrometers, P is between 50 nanometers and 25 micrometers, and D50>4P. In some embodiments, D50 is between 10 micrometers and 5000 micrometers, P is between 50 nanometers and 25 micrometers, and D50>4P. In some embodiments, D50 is between 25 micrometers and 5000 micrometers, P is between 50 nanometers and 25 micrometers, and D50>6P. In some embodiments, D50 is between 10 micrometers and 5000 micrometers, P is between 50 nanometers and 25 micrometers, and D50>6P.

The present disclosure also provides a method of making a polymer composite sheet having a first major surface, comprising: (i) a thermoplastic polymer having a number average molecular weight of from 5×10 ⁴ g/mol to 5×10 ⁷ g/mol; providing a solvent in which the thermoplastic polymer is soluble and a soft ferromagnetic particulate material; and (ii) mixing the thermoplastic polymer, solvent and soft ferromagnetic particulate material to form an admixture containing the soft ferromagnetic particulate material. (iii) forming a thermoplastic polymer solvent solution containing soft ferromagnetic particles into a sheet; and (iv) inducing phase separation of the thermoplastic polymer from the solvent. and (v) removing at least a portion of the solvent, thereby forming a polymer composite sheet having a thermoplastic polymer network structure and soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure. forming, wherein the weight fraction of the soft ferromagnetic particulate material is between 0.80 and 0.98, based on the total weight of the polymer composite sheet.

The solvent is selected so that it can dissolve the thermoplastic polymer at the specified temperature to form a miscible thermoplastic polymer solvent solution. Heating the solution to a high temperature can facilitate dissolution of the thermoplastic polymer.

In some embodiments, the step of mixing is 20°C to 300°C, 20°C to 250°C, 20°C to 200°C, 20°C to 150°C, 40°C to 300°C, 40°C to 250°C, 40°C It is carried out at temperatures of -200°C, 40°C to 150°C, 60°C to 200°C or even 60°C to 150°C.

The soft ferromagnetic particulate material can be added at the beginning of the mixing process, before melting the thermoplastic polymer, after melting the thermoplastic polymer, or any time before or after. In order to minimize the amount of shear force to which the soft ferromagnetic particle material is exposed, the polymer is completely dissolved and It may be advantageous to add the soft ferromagnetic particulate material after the miscible thermoplastic polymer solvent solution has been formed.

Solvents, such as the first solvent, are not particularly limited except that they must be selected to form a miscible thermoplastic polymer solvent solution. A solvent may be a blend of two or more individual solvents. In some embodiments, when the thermoplastic polymer is at least one of polyolefins such as polyethylene and polypropylene, solvents include mineral oil, tetralin, decalin, 1,2-dichlorobenzene, cyclohexane-toluene mixtures, at least one of dodecane, paraffin oil, kerosene, p-xylene/cyclohexane mixture (1/1 weight/weight), camphene, 1,2,4 trichlorobenzene, octane, orange oil, vegetable oil, castor oil and palm kernel oil one can be selected. In some embodiments, when the thermoplastic polymer is polyvinylidene fluoride, the solvent can be at least one of ethylene carbonate, propylene carbonate and 1,2,3-triacetoxypropane.

Solvents can be removed by evaporation, and solvents with high vapor pressure are particularly suitable for this method of removal. However, if the first solvent has a low vapor pressure, a second solvent with a higher vapor pressure can be used to extract the first solvent, followed by evaporation of the second solvent. For example, in some embodiments, when mineral oil is used as the first solvent, hot (eg, about 60° C.) isopropanol, or methyl nonafluorobutyl ether (C ₄ F ₉ OCH ₃ ), ethyl-nonafluorobutyl ether (C ₄ F ₉ OC ₂ H ₅ ), and a blend of trans-1,2-dichloroethylene (available under the tradename NOVEC 72DE from 3M Company, St. Paul, Minnesota) as the second solvent. , extraction of the first solvent, followed by evaporation of the second solvent.

In some embodiments, when at least one of vegetable oil or palm kernel oil is used as the first solvent, isopropanol at elevated temperature, eg, about 60° C., can be used as the second solvent. In some embodiments, water can be used as the second solvent when ethylene carbonate is used as the first solvent.

mixing a thermoplastic polymer, a solvent and a soft ferromagnetic particulate material to form a miscible thermoplastic polymer solvent solution containing the soft ferromagnetic particulate material, followed by a miscible thermoplastic polymer solvent containing the soft ferromagnetic particulate material; Form the solution into a sheet.

Forming a thermoplastic polymer solvent solution containing soft ferromagnetic particles into a sheet is generally performed prior to the step of inducing phase separation. Forming into a sheet can be performed by techniques known in the art, including knife coating, roll coating, such as through a defined nip, and extrusion, such as through a die. Extrusion includes, but is not limited to, extrusion through a die having appropriate sheet dimensions, ie die gap width and thickness. In one embodiment, the miscible thermoplastic polymer solvent solution containing the soft ferromagnetic particulate material has a paste-like consistency and is extruded, e.g. It is formed into a sheet by extrusion through a die with.

After the thermoplastic polymer solvent solution containing the soft ferromagnetic particles is formed into a sheet, the thermoplastic polymer is allowed to phase separate. Phase separation is performed by inducing phase separation of the thermoplastic polymer. Several techniques can be used to induce phase separation, including but not limited to at least one of thermally induced phase separation and solvent induced phase separation.

In some embodiments, inducing phase separation comprises at least one of thermally induced phase separation and solvent induced phase separation. Thermally induced phase separation can occur when the temperature at which the induced phase separation occurs is below the mixing temperature of the step of mixing the thermoplastic polymer, solvent and soft ferromagnetic particulate material. This may be accomplished by cooling the miscible polymer solvent solution containing the soft ferromagnetic particle material if the mixing step is performed near room temperature, or by first cooling the solution containing the soft ferromagnetic particle material. This may be accomplished by heating the miscible polymer solvent solution to an elevated temperature (either during or after mixing) and subsequently reducing the temperature of the miscible polymer solvent solution containing the soft ferromagnetic particulate material. induces phase separation of the thermoplastic polymer. In either case, the cooling step results in phase separation of the thermoplastic polymer from the solvent.

Solvent-induced phase separation can be carried out by adding a poor solvent for the thermoplastic polymer as a second solvent to the miscible polymer solvent solution containing the soft ferromagnetic particle material, or the soft ferromagnetic Accomplished by removing at least a portion of the solvent of the miscible polymer solvent solution containing the particulate material, for example by evaporating at least a portion of the solvent of the miscible polymer solvent solution containing the soft ferromagnetic particulate material , which induces phase separation of the thermoplastic polymer.

A combination of phase separation techniques can also be utilized, for example, a combination of thermally induced phase separation and solvent induced phase separation. Thermally induced phase separation can be advantageous because it also promotes dissolution of the thermoplastic polymer when the mixing step is performed at elevated temperatures.

In some embodiments, the step of inducing phase separation is 5°C to 300°C below the temperature of the mixing step, 5°C to 250°C below the temperature of the mixing step, 5°C to 200°C below the temperature of the mixing step. 5°C to 150°C lower than the temperature of the mixing step, 15°C to 300°C lower than the temperature of the mixing step, 15°C to 250°C lower than the temperature of the mixing step, 15°C lower than the temperature of the mixing step. ~200°C below, 15°C to 130°C below the temperature of the mixing step or even 25°C to 110°C below the temperature of the mixing step.

After inducing phase separation, at least a portion of the solvent is removed from the polymer composite, thereby having a thermoplastic polymer network structure and soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure. A polymer composite sheet is formed wherein the weight fraction of the soft ferromagnetic particulate material is between 0.80 and 0.98, based on the total weight of the polymer composite sheet.

Solvents can be removed by evaporation, and solvents with high vapor pressure are particularly suitable for this method of removal. However, if the first solvent has a low vapor pressure, a second solvent with a higher vapor pressure can be used to extract the first solvent, followed by evaporation of the second solvent. In some embodiments, at least 10 weight percent to 100 weight percent, at least 30 weight percent to 100 weight percent, at least 50 weight percent to 100 weight percent, at least 60 weight percent to 100 weight percent, at least 70 weight percent to 100 weight percent percent, at least 80 weight percent to 100 weight percent, at least 90 weight percent to 100 weight percent, at least 95 weight percent to 100 weight percent, or even at least 98 weight percent to 100 weight percent of the solvent is removed from the network structure of the thermoplastic polymer. be done.

After either the step of inducing phase separation or the step of removing at least a portion of the solvent, the formed thermoplastic polymer network structure can be disrupted to densify the polymer composite. This can be accomplished by applying at least one of compressive and tensile forces to the polymer composite, eg, a polymer composite sheet. In some embodiments, the method of making a polymer composite applies at least one of a compressive force and a tensile force after removing the solvent to densify the polymer composite sheet. further comprising:

At least one of compressive and tensile forces may be applied by techniques known in the art. For example, the compressive force is achieved by passing the polymer composite, e.g., a polymer composite sheet, through the nip of a pair of nip rolls having a gap smaller than the thickness of the polymer composite, e.g., by calendering. can be done. Unlike conventional composites that do not have a thermoplastic polymer network structure, the final density of the polymer composite depends on the degree of disruption of the thermoplastic polymer network structure, e.g. Depending on the nip thickness to thickness can be controlled.

In another example, a tensile force may be applied to a polymer composite, such as a polymer composite sheet, via a tentering process. Unlike conventional composites that do not have a thermoplastic polymer network structure, the final density of the polymer composite depends on the degree of collapse of the thermoplastic network structure, e.g. The amount of stretching can be controlled.

If an anisotropic soft ferromagnetic particle material is used, the process used to make the polymer composite, e.g. The process used to form the particles can also orient the soft ferromagnetic particle material, eg, the soft ferromagnetic particle flake material. When the polymer composite is in the form of a polymer composite sheet having a first major surface, the method of making the polymer composite comprises: orienting the anisotropic soft ferromagnetic grain material so that it is oriented within at least 25 degrees, within at least 20 degrees, within at least 15 degrees, or even within at least 10 degrees with respect to the first major surface of may further include:

In some embodiments, the largest length dimension of the anisotropic soft ferromagnetic particulate material can be oriented in the machine direction of the process used to make the polymer composite sheet. When the polymer composite is in the form of a polymer composite sheet having a first major surface and the soft ferromagnetic particle material is a soft ferromagnetic particle flake material, each flake having a first major surface, the polymer composite The method of making the body is such that a majority of the first major surface of the flakes are within at least 25 degrees, within at least 20 degrees, within at least 15 degrees, or even within at least 10 degrees relative to the first major surface of the adjacent polymer composite sheet. Orienting the soft ferromagnetic particle flake material so that it is oriented to within a degree. In some embodiments, the first major surface of the soft ferromagnetic particle flake material can be oriented in the machine direction of the process used to manufacture the polymer composite sheet.

List of Exemplary Embodiments Selected embodiments of the present disclosure include, but are not limited to:

In a first embodiment, the present disclosure is a polymer composite comprising:
a network structure of a thermoplastic polymer;
a soft ferromagnetic particulate material dispersed within the network structure of the thermoplastic polymer, wherein the weight fraction of the soft ferromagnetic particulate material is between 0.80 and 0.98, based on the total weight of the polymer composite. and the thermoplastic polymer provides a polymer conjugate having a number average molecular weight between 5×10 ⁴ g/mol and 5×10 ⁷ g/mol.

In a second embodiment, the present disclosure provides a polymer conjugate according to the first embodiment, wherein the thermoplastic polymer has a number average molecular weight of 1×10 ⁵ g/mole to 1×10 ⁷ g/mole. offer.

In a third embodiment, the present disclosure provides a polymer conjugate according to the first embodiment, wherein the thermoplastic polymer has a number average molecular weight of 1×10 ⁶ g/mole to 5×10 ⁶ g/mole. offer.

In a fourth embodiment, the present disclosure provides a polymer composite according to any one of the first through third embodiments, wherein the network structure of the thermoplastic polymer is plastically deformed.

In a fifth embodiment, the present disclosure provides a polymer composite according to the fourth embodiment, wherein the thermoplastic polymer network structure is plastically deformed by at least one of compressive and tensile forces. do.

In a sixth embodiment, the present disclosure relates to the first to fifth embodiments, wherein the weight fraction of the soft ferromagnetic particulate material is 0.85-0.97, based on the total weight of the polymer composite. A polymer composite according to any one of

In a seventh embodiment, the present disclosure provides the weight fraction of the soft ferromagnetic particulate material, based on the total weight of the polymer composite, of 0.90 to 0.96. A polymer composite according to any one of

In an eighth embodiment, the present disclosure provides the polymer composite of any one of the first through seventh embodiments, wherein the density of the polymer composite is between 1.5 g/cm ³ and 6 g/cm ³ . I will provide a.

In a ninth embodiment, the present disclosure provides the polymer of any one of the first through eighth embodiments, wherein the density of the polymer composite is between 1.5 g/cm ³ and 5.5 g/cm ³ . Provide a complex.

In a tenth embodiment, the present disclosure provides that the soft ferromagnetic particle material is a soft ferromagnetic particle flake material, each flake having a first major surface and a thickness perpendicular to the first major surface of the flake There is provided a polymer composite according to any one of the first through ninth embodiments, having

In an eleventh embodiment, the present disclosure provides that the flakes of the soft ferromagnetic particle flake material have a median diameter D50 and a median maximum thickness Tm, and a median aspect ratio D50/Tm of 5/1 to 1000/1. There is provided a polymer composite according to the tenth embodiment.

In a twelfth embodiment, the present disclosure provides a third A polymer composite according to the tenth or eleventh embodiment is provided.

In a thirteenth embodiment, the present disclosure provides a polymer composite according to the twelfth embodiment, wherein D50 is from 25 micrometers to 5000 micrometers and P is from 50 nanometers to 25 micrometers. do.

In a fourteenth embodiment, the present disclosure provides that the soft ferromagnetic particle material is Fe—Cr alloy, Fe—Si alloy, FeCoB, Fe-based amorphous alloy, nanocrystalline Fe-based oxide and nanocrystalline Fe-based Provided is a polymer composite according to any one of the first through thirteenth embodiments, which is at least one of nitrides, nickel-based alloys, CoNbZr, and boron-based amorphous alloys.

In a fifteenth embodiment, the present disclosure provides that the thermoplastic polymer comprises polyurethanes, polyesters, polyamides, polyethers, polycarbonates, polyimides, polysulfones, polyphenylene oxides, polyacrylates, polymethacrylates, polyolefins, styrene and styrenic random copolymers and block copolymers. There is provided a polymer composite according to any one of the first through fourteenth embodiments, comprising at least one of copolymers, chlorinated polymers, fluorinated polymers, and copolymers of ethylene and chlorotrifluoroethylene.

In a sixteenth embodiment, the present disclosure provides a polymer composite according to any one of the first through fifteenth embodiments, wherein the thermoplastic polymer has at least one melting point between 80°C and 350°C. do.

In a seventeenth embodiment, the present disclosure provides the polymer composite of any one of the first through sixteenth embodiments, wherein the thermoplastic polymer has at least one melting point between 120°C and 300°C. I will provide a.

In an eighteenth embodiment, the present disclosure provides the polymer composite of the first through seventeenth embodiments, wherein the polymer composite is in the form of a sheet having a first major surface and a thickness of 20 micrometers to 5000 micrometers. A polymer conjugate according to any one is provided.

In a nineteenth embodiment, the present disclosure provides that the soft ferromagnetic particle material is a soft ferromagnetic particle flake material, each flake having a first major surface and a thickness perpendicular to the first major surface of the flake and , and a majority of the first major surfaces of the flakes are oriented within at least 25 degrees to the first major surface of the adjacent polymer composite sheet. provides a polymer composite of

In a twentieth embodiment, the present disclosure provides that when the polymer composite is in the form of a sheet having a thickness of 20 micrometers to 300 micrometers, the polymer composite can bend to form a radius of curvature of 10 mm. There is provided a polymer composite according to any one of the first through nineteenth embodiments, which can be.

In a twenty-first embodiment, the present disclosure provides that the soft ferromagnetic particle material has a coercive force of 1000 A/m or less, optionally the soft ferromagnetic particle material has a coercive force of 1 A/m to 1000 A/m , provides a polymer composite according to any one of the first to twentieth embodiments.

In a twenty-second embodiment, the present disclosure provides the polymer conjugate of any one of the first through twenty-first embodiments, wherein the magnetic saturation induction is between 600mT and 1000mT.

In a twenty-third embodiment, the present disclosure provides a polymer composite according to any one of the first to twenty-second embodiments, having a relative magnetic permeability magnitude greater than 70 at 1 MHz.

In a twenty-fourth embodiment, the present disclosure provides that the network structure of the thermoplastic polymer is produced by induced phase separation of a miscible thermoplastic polymer solvent solution, optionally the induced phase separation comprises thermally induced phase separation and solvent induced phase separation. A polymer conjugate according to any one of the first to twenty-third embodiments is provided which is at least one of separating.

In a twenty-fifth embodiment, the present disclosure provides any one of the first through twenty-fourth embodiments, wherein 10 volume percent to 100 volume percent of the pores of the thermoplastic polymer network structure are free of liquids and solids. A polymer composite as described is provided.

In a twenty-sixth embodiment, the present disclosure provides the first to twenty-fifth embodiments, wherein the volume fraction of the soft ferromagnetic particulate material is 0.10-0.75, based on the total volume of the polymer composite. A polymer composite according to any one of

In a twenty-seventh embodiment, the present disclosure provides 10 volume percent to 100 volume percent, 30 volume percent to 100 volume percent, 50 volume percent to 100 volume percent, 60 volume percent to 100 volume percent of the pores of the thermoplastic polymer network structure. percent, 70 volume percent to 100 volume percent, 80 volume percent to 100 volume percent, 90 volume percent to 100 volume percent, 95 volume percent to 100 volume percent, or even 98 volume percent to 100 volume percent, liquids and solids. There is provided a polymer composite according to any one of the first through twenty-sixth embodiments, excluding.

In a twenty-eighth embodiment, the present disclosure provides a method of manufacturing a polymer composite sheet having a first major surface, comprising:
providing a thermoplastic polymer having a number average molecular weight between 5×10 ⁴ g/mol and 5×10 ⁷ g/mol, a solvent in which the thermoplastic polymer is soluble, and a soft ferromagnetic particulate material;
mixing a thermoplastic polymer, a solvent and a soft ferromagnetic particulate material to form a miscible thermoplastic polymer solvent solution containing the soft ferromagnetic particulate material;
forming a thermoplastic polymer solvent solution containing soft ferromagnetic particles into a sheet;
inducing phase separation of the thermoplastic polymer from the solvent;
removing at least a portion of the solvent, thereby forming a polymer composite sheet having a thermoplastic polymer network structure and a soft ferromagnetic particulate material dispersed within the thermoplastic polymer network structure; A manufacturing method is provided wherein the weight fraction of the soft ferromagnetic particulate material is between 0.80 and 0.98, based on the total weight of the polymer composite sheet.

In a twenty-ninth embodiment, the present disclosure provides a polymer composite sheet according to the twenty-eighth embodiment, wherein the step of inducing phase separation comprises at least one of thermally-induced phase separation and solvent-induced phase separation. A manufacturing method is provided.

In a thirtieth embodiment, the present disclosure provides a method of making a polymer composite sheet according to embodiments twenty-eighth or twenty-ninth, wherein the step of mixing is performed at a temperature of 20°C to 300°C.

In a thirty-first embodiment, the present disclosure contemplates any one of the twenty-eighth through thirtieth embodiments, wherein the step of inducing phase separation is carried out at a temperature between 5°C and 300°C below the temperature of the mixing step. A method for making the described polymer composite sheet is provided.

In a thirty-second embodiment, the present disclosure is according to any one of the twenty-eighth through thirty-first embodiments, wherein the forming is performed by at least one of extrusion, roll coating, and knife coating. of the polymer composite sheet.

In a thirty-third embodiment, the present disclosure applies at least one of a compressive force and a tensile force after the step of inducing phase separation or after the step of removing the solvent, whereby the polymer composite There is provided a method of making a polymer composite sheet according to any one of embodiments 28-32, further comprising densifying the sheet.

In a thirty-fourth embodiment, the present disclosure provides that the soft ferromagnetic particle material is a soft ferromagnetic particle flake material, each flake having a first major surface and a thickness perpendicular to the first major surface of the flake and There is provided a method of making a polymer composite sheet according to any one of embodiments 28-33, comprising:

In a thirty-fifth embodiment, the present disclosure provides such that a majority of the first major faces of the flakes are oriented within at least 25 degrees with respect to the first major face of the adjacent polymer composite sheet, A method of making a polymer composite sheet according to the thirty-fourth embodiment is provided, further comprising orienting the soft ferromagnetic particle flake material.

In a thirty-sixth embodiment, the present disclosure provides the polymer composite according to any of the first to twenty-seventh embodiments, wherein the particle fraction is greater than 52% by volume, and the polymer composite sheet has a coercivity of 240 A/m or less. Provide a body sheet.

In a thirty-seventh embodiment, the present disclosure provides a polymer composite sheet according to thirty-sixth embodiment, wherein the polymer composite sheet has a coercivity of 200 A/m or less.

In a thirty-eighth embodiment, the present disclosure provides a method of making a polymer composite sheet according to the thirty-third embodiment, further comprising applying vibrational energy to the polymer composite sheet concurrently with applying a compressive force. offer.

Implementation of exemplary embodiments of the present disclosure is further described with respect to the following detailed examples. These examples are provided to further demonstrate various specific preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the scope of the disclosure.

A polymer composite comprising a thermoplastic polymer network structure and soft ferromagnetic particulate material was prepared, densified and tested. Dimensions and electromagnetic properties were evaluated along with wireless power transfer efficiency, as shown in the examples below. These examples are for illustrative purposes only and are not intended as limitations on the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and elsewhere herein are by weight unless otherwise specified.

Although the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. At a minimum, each numerical parameter should be interpreted at least by applying conventional rounding techniques in light of the number of significant digits reported, but this is not a doctrine of equivalents to the scope of the claims. It is not intended to limit its application.

Materials Unless otherwise stated, all parts, percentages, ratios, etc. in the examples and elsewhere herein are by weight. Solvents and other reagents used were obtained from Sigma-Aldrich Chemical Company (Milwaukee, Wis.) unless otherwise noted. In addition, Table 1 provides abbreviations and suppliers for all materials used in the examples below.

Test Methods Some of the examples of the present disclosure were evaluated using the following test methods.

Density Determination Test Method The dried polymer composite was cut into strips approximately 8 cm x 20 cm. Three pieces approximately 6 cm×7 cm each were cut from one large strip for density measurement according to the ASTM F-1315 (Original: 1990, Approved: March 1, 2014) standard method. The area of the sample was calculated by cutting the sample with a die of known length and width. Film thickness was measured using a TMI Model 49-70 Precision Micrometer (available from Testing Machines, Inc. of New Castle, Del.). The volume was calculated from the area and thickness of the polymer composite. Finally, the mass of the film was determined using an analytical balance. Density was calculated from the measured mass and volume.

Using the known densities of the components (density of PE=0.94 g/cm ³ , density of MP1=6.9 g/cm ³ ) and actual compositions (PE=5 wt % and MP1=95 wt %), The theoretical density of the composite without voids (pores) was calculated. Using the theoretical and measured densities, the porosity (%) was calculated as follows.
Porosity (%) = [1-(measured density / theoretical density)] x 100

From the calculated porosity, the volume-based MP1 filling amount (%) was calculated as follows.
MP1 filling amount (%) = [(Mp / ρ _p ) / (Mp / ρ _p + Me / ρ _e )] × (1-porosity) × 100
where Mp and Me are the mass fractions of MP1 and PE in the complex, respectively. Similarly, ρ _p and ρ _e are the densities of MP1 and PE, respectively.

Electromagnetic test method I. Static magnetic properties:
Samples of the polymer composite were cut into 6 mm discs prior to magnetic measurements. Magnetic hysteresis loops (MH curves) were recorded using a Lake Shore Cryotronics (Westerville, Ohio) vibrating sample magnetometer 7400-S. A magnetic field H was applied in the plane of the sample. The magnetic field range was set to H=±4 kOe and the saturation magnetization Ms was measured at full saturation (|H|=4 kOe). The magnetic field H was measured in steps of 0.14 Oe and the coercive field Hc was determined near M=0 by linear fitting based on the 6 points on the MH curve adjacent to M=0.

II. Dynamic magnetic properties:
Samples of the polymer composite were cut into toroids with an outer diameter of 18 mm and an inner diameter of 5 mm. The real and imaginary parts of the relative permeability _μr were measured using a Keysight Technologies (Santa Clara, Calif.) magnetic test fixture 16454A and an impedance measuring instrument E4990A. Data were analyzed according to Keysight's manual for 16454A.

III. DC electrical characteristics:
Polymer composite samples were cut into 18 mm disks for out-of-plane measurements and strips of approximately 50 x 20 mm for in-plane measurements. In-plane and out-of-plane DC resistivities were measured using a 2400 Keithley Instruments (Cleveland, OH) sourcemeter. The current limit was set at 150 nA. The resistivity ρ is determined by the equation: R = ρl/S, where R is the measured resistance value, l is the distance the current travels in the sample, and S is the cross-sectional area of the current path. available).

IV. AC electrical characteristics:
In-plane resistivity was measured using a microstripline, where the polymer composite sample is a 3 mm x 4 mm strip. Tests were performed in the frequency range 0.3-20 MHz. An external magnetic field H=1.6 kOe was applied in the plane of the sample to magnetically saturate the sample and minimize inductive effects. A Rohde & Schwarz (Munich, Germany) vector network analyzer ZNB20 was used to measure the resistance of the samples. Out-of-plane resistivity was measured using a Keysight Technologies (Santa Clara, Calif.) Dielectric Test Fixture 16453A and Impedance Measuring Instrument E4990A with a 6 mm diameter sample disk. For both in-plane and out-of-plane measurements, the resistivity is R=ρl/S, where R is the measured resistance, l is the distance through which the current flows in the sample, and S is , which is the cross-sectional area of the current path).

Wireless Power Transfer Efficiency Test Method Efficiency of the entire wireless power transfer system at 5 watts according to the Wireless Power Consortium (WPC) 1.1 specification, which is the Qi standard (as opposed to power transfer efficiency between coils). ) evaluated the effectiveness of the polymer composites in concentrating and redirecting magnetic flux. For these measurements, 32 mm x 48 mm polymer composite samples were used.

The test system was custom built using a Qi standard compliant 5 Watt wireless charging design kit (Wurth Elektronik (Wurth Elektronik GmbH & Co. (KG, Germany))/Texas Instruments (Dallas, TX) model: 760308). The design kit includes a transmitter coil (Wurth Electronics model: 760308111) and a receiver coil (Wurth Electronics model: 760308103202). The configuration of the apparatus is as follows. Transmitter coil isolator (ferrite sheet 3 mm x 52 mm x 52 mm), transmitter coil placed on top of isolator, 2.4 mm thick x 70 mm x 70 mm acrylic sheet placed on top of transmitter coil, vertically aligned with transmitter coil. A receiver coil placed on an acrylate sheet, a polymer composite sample placed on top of the receiver coil, and a stainless steel plate approximately 1 mm thick x 32 mm x 48 mm placed on top of the polymer composite sample (with the battery case imitated).

The receiver coil was driven by a DC power supply E3645A from Agilent (Santa Clara, Calif.) set at 5.0 V in constant voltage mode. BK Precision Corp. operating in constant current mode. A DC electronic load 8600 from (Yorba Linda, Calif.) was used to monitor the received power. To quantify the effectiveness of the magnetic composite material in concentrating and directing the magnetic flux, the sample was placed over the receiver coil and an approximately 1 mm thick x 32 mm x 48 mm stainless steel plate (simulating a battery case) was placed over the polymer composite. placed on the sample. Calculate the wireless power transfer efficiency from the measured input and output currents and set the voltage at the output current to 0.6 Amp.
WPT efficiency (%) = (output voltage) (output current) / (input voltage) (input current) x 100

Preparative Examples Example 1 (Ex. 1) Polymer Composite Film MP1 particles and PE were individually weighed to give a total MP1:PE weight ratio of 95:5. The individual components were then placed in a mixing bowl of a Lancaster Mixture (K-Lab, Kercher Industries, Inc. (Lebanon, Pa.)). The powders were dry blended together for 45 minutes by rotating both the mixing bowl and shaft at the 50% setting. After 45 minutes mineral oil (MO) was weighed to give a solids (PE+MP1): mineral oil weight ratio of 63:37.

Mineral oil was slowly dispensed through the upper multi-orifice port while mixing the powder. Once all the mineral oil was dispensed, the blend was mixed for an additional 45 minutes to obtain a thick paste-like consistency. The blend was then scooped into 5 gallon pails.

The blend was passed through an 8 inch (20.3 cm) drop die (Nordson Extrusion Die Industries (Chippewa Falls) at 177°C using a pail filling pump (X20 Graco Inc., Minneapolis, Minn.) with a flow control plate. , WI USA)) into open barrel zone #2 of a twin-screw extruder (25 mm co-rotating twin-screw extruder, Berstorff, Germany) at about 204°C.

The hot film emerging from the die was quenched on a smooth casting wheel at 40°C. The speed of the casting wheel was adjusted to produce films with various thicknesses from about 0.3 mm to 0.6 mm thick. The mineral oil in the 8 inch (20.3 cm) by 18 inch (45.7 cm) films was then extracted with ES fluid by immersing the films in ES fluid three times for 20 minutes each.

The ES fluid was then evaporated from each sample by suspending the film in a fume hood. Thus, a polymer composite of Example 1 (Ex. 1) was produced. It was then used for further characterization and densification using the test methods listed above.

Ex. A cross-sectional SEM image of the polymer composite of No. 1 is shown in FIG. As seen in Figure 1, the magnetic flakes in the prepared sample (before densification) are held together by the intertwined polymer fibrils (network structures of thermoplastic polymers) created during the phase separation process. It is Ex. 1 has a large porosity.

Example 2 (Ex.2) Densified Polymer Composite Film Ex. A strip of 1 was passed through the calender nip rolls defining a constant gap between the nip rolls. The nip gap was adjusted until the final film thickness was about 150 microns. As a result, Ex. Two densified polymer composite films were made.

This film was then cut into 6 cm x 7 cm pieces and used for density measurements (test methods listed above) and SEM analysis. A densified sample, Ex. 2 (Fig. 2) shows highly packed flakes still held together by polymer fibrils. However, most of the voids (pores) in the film disappeared during the densification process.

Example 3 (Ex. 3) Ultrasonically Densified Polymer Composite Film MP1 particles and PE were weighed separately to give a total MP1:PE weight ratio of 95:5. The individual components were then placed in a mixing bowl of a Lancaster Mixture (K-Lab, Kercher Industries, Inc. (Lebanon, Pa.)). The powders were dry blended together for 45 minutes by rotating both the mixing bowl and shaft at the 50% setting. After 45 minutes mineral oil (MO) was weighed to give a solids (PE+MP1):mineral oil weight ratio of 55.5:44.5.

Mineral oil was slowly dispensed through the upper multi-orifice port while mixing the powder. Once all the mineral oil was dispensed, the blend was mixed for an additional 45 minutes to obtain a thick paste-like consistency. The blend was then scooped into 5 gallon pails (approximately 19.5 liters).

The blend was passed through an 8 inch (20.3 cm) drop die (Nordson Extrusion Die Industries (Chippewa Falls) at 177°C using a pail filling pump (X20 Graco Inc., Minneapolis, Minn.) with a flow control plate. , WI)) into open barrel zone #2 of a twin-screw extruder (25 mm co-rotating twin-screw extruder, Berstorff, Germany) at about 204°C.

The hot film emerging from the die was quenched on a smooth casting wheel at 40°C. The speed of the casting wheel was adjusted to produce films with various thicknesses from about 0.3 mm to 0.6 mm thick. The mineral oil in the 8 inch (20.3 cm) by 18 inch (45.7 cm) films was then extracted with ES fluid by immersing the films in ES fluid three times for 20 minutes each. The ES fluid was then evaporated from each sample by suspending the film in a fume hood.

A 1.5 inch (3.8 cm) wide strip of material was densified using an ultrasonically assisted calender with a set of nip rolls. The horizontal axis of the bottom roll is fixed to the vertical axis and the horizontal axis of the top roll is ultrasonically vibrated vertically at 20 KHz. The ultrasonically vibrated roll was powered by a DCX power supply model (Branson Ultrasonics, Danbury, Conn.) used in continuous mode.

The ultrasonic-assisted densification line speed was 5 ft/min (152 cm/min) and the gap setting was set at 0.006 inch (0.15 mm). The material was passed through the nip rolls twice, first at 100% amplitude (representing a peak-to-peak amplitude of 0.05 mm) and then at 60% amplitude. The nip gap and amplitude settings were selected to produce final films ranging in thickness from 150 to 200 microns.

As a result, Ex. Three densified polymer composite films were made. The film was then cut into 6 cm x 7 cm pieces and used for density measurements (test methods listed above) and magnetic characterization.

Results Table 2 below shows Ex. 1 and Ex. 2 shows the measured thickness, density, porosity, and volumetric loading of sendust flakes (MP1) in the films of No. 2. For comparison, the same parameters of CE-1 with the same sendust flakes using polyurethane as binder. Ex. The loading of 2 (densified polymer composite film) is significantly higher than that of the commercial product CE-1. Ex. By passing a sample of 1 through the nip rolls several times and/or by reducing the calender nip gap, 100 micrometer thick films were shown to have a high volume loading of up to 68%.

Table 3 lists the main electromagnetic properties of the films of the examples [DC resistivity, real part (μ′) and imaginary part (μ″) of magnetic permeability measured at 6.78 MHz, saturation magnetization (Ms), coercivity (Hc), and the loss tangent (Tan(α))].

These results are shown in Ex. 2 shows that the saturation magnetization of the densified polymer composite film is significantly higher than that of CE-1.

Table 4 shows the thickness and wireless power transfer efficiency (WPT efficiency) of each of the examples and comparative examples.

Although specific exemplary embodiments have been described in detail herein, modifications, variations, and equivalents of these embodiments will readily occur to those skilled in the art, upon understanding the foregoing description. It will be appreciated what can be done. Therefore, it should be understood that this disclosure should not be unduly limited to the exemplary embodiments thus far described.

As used herein, the recitation of numerical ranges by endpoints includes all numbers subsumed within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.8, 4, and 5). Accordingly, unless otherwise indicated, the numerical parameters set forth in the foregoing specification, the accompanying enumeration of embodiments, and the claims which follow should not be construed as desired by one of ordinary skill in the art using the teachings of this disclosure. It can vary depending on the properties. At a minimum, each numerical parameter should be interpreted at least by applying conventional rounding techniques in light of the number of significant digits reported, which is equivalent to the scope of the claimed embodiments. It is not intended to limit the application of the theory.

Further, all publications and patents referred to herein are incorporated by reference in their entirety to the same extent as if each individual publication or patent were specifically and individually indicated to be incorporated by reference. incorporated. Various exemplary embodiments have been described. These and other embodiments are within the scope of the following claims.

Claims (17)

A polymer composite sheet ,
a network structure of a thermoplastic polymer;
a soft ferromagnetic particulate material dispersed within the network structure of said thermoplastic polymer;
The weight fraction of the soft ferromagnetic particulate material is 0.80-0.98, based on the total weight of the polymer composite sheet , and the thermoplastic polymer is 5×10 ⁴ g/mol-5× having a number average molecular weight of 10 ⁷ g/mole;
A polymer composite sheet having a particle fraction of more than 52% by volume and a coercive force of 240 A/m or less. 2. The method of claim 1, wherein the thermoplastic polymer network structure is plastically deformed, optionally wherein the thermoplastic polymer network structure is plastically deformed by at least one of compressive and tensile forces. Polymer composite sheet . The polymer composite sheet according to claim 1, wherein the polymer composite sheet has a density of 1.5 g/cm ³ to 6 g/cm ³ . said soft ferromagnetic particle material being a soft ferromagnetic particle flake material, each flake having a first major surface and a thickness perpendicular to said first major surface of said flake; The polymer composite of claim 1, wherein the flakes of said soft ferromagnetic particle flake material have a median diameter D50 and a median maximum thickness Tm, and a median aspect ratio D50/Tm of 5/1 to 1000/1. body sheet . the flakes of said soft ferromagnetic particle flake material have a median diameter D50, said network structure of said thermoplastic polymer has an average pore diameter P, D50 > 2P, optionally D50 from 25 micrometers 5000 micrometers, and P is between 50 nanometers and 25 micrometers . The soft ferromagnetic particle materials include Fe--Cr alloys, Fe--Si alloys, FeCoB, Fe-based amorphous alloys, nanocrystalline Fe-based oxides and nanocrystalline Fe-based nitrides, nickel-based alloys, CoNbZr and boron. 2. The polymer composite sheet of claim 1, wherein the sheet is at least one of the following amorphous alloys. said thermoplastic polymers are polyurethanes, polyesters, polyamides, polyethers, polycarbonates, polyimides, polysulfones, polyphenylene oxides, polyacrylates, polymethacrylates, polyolefins, styrene and styrenic random and block copolymers, chlorinated polymers, fluorinated polymers, and at least one of copolymers of ethylene and chlorotrifluoroethylene . The polymer composite sheet of claim 1, wherein said thermoplastic polymer has at least one melting point between 120°C and 200°C. The polymer composite sheet is in the form of a sheet having a first major surface and a thickness of 20 micrometers to 5000 micrometers, and optionally the soft ferromagnetic particle material is a soft ferromagnetic particle flake material. wherein each flake has a first major surface and a thickness perpendicular to said first major surface of said flake, and a majority of said first major surface of said flake is adjacent said polymer composite 2. The polymer composite sheet of Claim 1 oriented within at least 25 degrees with respect to the first major surface of the body sheet . 2. The method of claim 1, wherein the polymer composite sheet is in the form of a sheet having a thickness of 20 micrometers to 300 micrometers, and the polymer composite sheet can be bent to form a curvature radius of 10 mm. A polymer composite sheet as described. The polymer of claim 1, wherein the soft magnetic particle material has a coercivity of 1000 A/m or less, a magnetic saturation induction of 600 mT to 1000 mT, or a relative permeability magnitude of greater than 70 at 1 MHz. composite sheet . The polymer composite sheet according to claim 1, wherein the volume fraction of said soft ferromagnetic particulate material is between 0.10 and 0.80 based on the total volume of said polymer composite sheet . A method for producing a polymer composite sheet having a first major surface, comprising:
providing a thermoplastic polymer having a number average molecular weight between 5×10 ⁴ g/mol and 5×10 ⁷ g/mol, a solvent in which said thermoplastic polymer is soluble, and a soft ferromagnetic particulate material;
mixing the thermoplastic polymer, the solvent and the soft ferromagnetic particulate material to form a miscible thermoplastic polymer solvent solution containing the soft ferromagnetic particulate material;
forming the thermoplastic polymer solvent solution containing the soft ferromagnetic particles into a sheet;
inducing phase separation of the thermoplastic polymer from the solvent;
removing at least a portion of said solvent, thereby forming a polymer composite sheet having a thermoplastic polymer network structure and a soft ferromagnetic particulate material dispersed within said thermoplastic polymer network structure. , the weight fraction of the soft ferromagnetic particulate material is 0.80 to 0.98, based on the total weight of the polymer composite sheet; at least one of separation and solvent-induced phase separation;
A method of manufacturing further comprising applying vibrational energy to said polymer composite sheet concurrently with applying a compressive force, said vibrational energy being ultrasonic energy. The step of mixing is performed at a temperature of 20° C. to 300° C., and optionally the step of inducing phase separation is performed at a temperature of 5° C. to 300° C. below the temperature of the step of mixing. 14. The method for producing a polymer composite sheet according to 13. 14. The method of making a polymer composite sheet according to claim 13, wherein the forming step is performed by at least one of extrusion, roll coating and knife coating. 14. The method of claim 13, further comprising applying at least one of a compressive force and a tensile force after the step of removing the solvent to thereby densify the polymer composite sheet. A method for producing a polymer composite sheet. 2. The polymer composite sheet according to claim 1, wherein the polymer composite sheet has a coercive force of 200 A/m or less.

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