Electromagnetic interference (EMI) absorber comprising carbon nanostructure (CNS) filler in a liquid crystal polymer (LCP) matrix

Abstract

Electromagnetic interference (EMI) absorbers and compositions comprising carbon nanostructure (CNS) fillers within a liquid crystal polymer (LCP) matrix are disclosed.SOLUTION: In an exemplary embodiment, an electromagnetic interference (EMI) absorber includes a carbon nanostructure filler in a matrix. The matrix comprises a liquid crystal polymer. The EMI absorber includes at least about 0.1 weight percent but no more than about 5 weight percent of a carbon nanostructure filler in a matrix.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to electromagnetic interference (EMI) absorbers comprising carbon nanostructure (CNS) fillers within a liquid crystal polymer (LCP) matrix. [Background technology]

[0002] This section provides background information related to the present disclosure that is not necessarily prior art. A common problem in the operation of electronic devices is the generation of electromagnetic radiation within the equipment's electronic circuits. Such radiation can cause electromagnetic interference (EMI) or radio frequency interference (RFI), which can disrupt the operation of other electronic devices within a certain proximity. Without proper shielding, EMI / RFI interference can cause degradation or complete loss of important signals, rendering electronic equipment inefficient or inoperable.

[0003] A common solution to ameliorating the effects of EMI / RFI is to use shields that absorb and / or reflect and / or redirect EMI energy. These shields are typically used to localize the EMI / RFI within its source and to isolate other devices that are near the EMI / RFI source.

[0004] As used herein, the term "EMI" should be considered to include and refer generally to EMI and RFI emissions, and the term "electromagnetic" should be considered to include and refer generally to electromagnetic and radio frequencies from external and internal sources. Accordingly, the term shielding (as used herein) broadly includes and refers to reducing (or limiting) EMI and / or RFI so that it does not interfere, such as by absorbing, reflecting, blocking, and / or redirecting energy, or some combination thereof, for example, for government compliance and / or the internal functioning of an electronic system. [Brief explanation of the drawings]

[0005] [Figure 1] FIG. 1 illustrates an injection-moldable thermoplastic EMI absorber pellet including carbon nanostructure (CNS) filler (eg, about 1.5 weight percent) within a liquid crystal polymer (LCP) matrix according to an exemplary embodiment of the present disclosure. [Figure 2] 2 and 3 include line graphs of dielectric constant versus frequency from 18 gigahertz (GHz) to 40 GHz for six EMI absorbers having different carbon nanostructure (CNS) filler loadings (0.5, 0.7, 0.8, 0.9, 1, and 1.5 CNS weight percent) within a liquid crystal polymer (LCP) matrix according to exemplary embodiments of the present disclosure. [Figure 3] Same as above. DETAILED DESCRIPTION OF THE INVENTION

[0006] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. As mentioned above, a common problem in the operation of electronic devices is the generation of electromagnetic radiation within the equipment's electronic circuitry. Such radiation can cause electromagnetic interference (EMI) or radio frequency interference (RFI), which can disrupt the operation of other electronic devices within a certain proximity. Without proper shielding, EMI / RFI interference can cause degradation or complete loss of important signals, thereby rendering electronic equipment inefficient or inoperable.

[0007] The use of EMI absorbers to provide adequate EMI shielding is particularly important in aerospace connectors for several reasons, including signal integrity, regulatory compliance, reliability, and safety. Overall, EMI absorbers play a key role in ensuring the performance, reliability, and safety of aerospace connectors in harsh environments.

[0008] Regarding signal integrity, sensitive electronic signals in aerospace systems can be disrupted by electromagnetic interference. EMI absorbers can be used to help maintain signal integrity by reducing or eliminating interference that can degrade performance or cause malfunctions.

[0009] Aerospace equipment must also meet strict regulatory standards for electromagnetic compatibility (EMC). EMI absorbers can be used to help ensure compliance with these regulations by minimizing electromagnetic radiation and susceptibility to external interference.

[0010] Reliability is a paramount concern in aerospace applications, and EMI absorbers can be used to help improve connector reliability by protecting electronic components from damage or malfunction caused by electromagnetic interference.

[0011] Additionally, aerospace systems may operate in challenging environments where electromagnetic interference can pose safety risks, in which case EMI absorbers may be used to help mitigate these safety risks by reducing or minimizing the likelihood of interference-related failures or malfunctions.

[0012] Disclosed herein are exemplary embodiments of EMI absorbers and EMI absorbing compositions (e.g., injection-moldable EMI absorbing compositions, pellets, etc.) that include carbon nanostructure (CNS) fillers within a liquid crystal polymer (LCP) matrix. Also disclosed are exemplary compositions for EMI absorbers and aerospace connectors that include such EMI absorbers.

[0013] Advantageously, exemplary embodiments of the EMI absorber and EMI absorbing composition disclosed herein may provide or include one or more (but not necessarily any or all) of the following features and advantages: In exemplary embodiments, the EMI absorber and EMI absorbing composition disclosed herein (e.g., injection-moldable EMI absorbing compositions, pellets, etc.) may be sufficiently lightweight for aerospace applications and / or may have sufficiently low viscosity and good flowability to be easily poured, cast, or molded (e.g., by injection molding, etc.) into shapes or patterns (e.g., along parts of aerospace connectors, etc.). In exemplary embodiments, the EMI absorber and EMI absorbing composition may have a sufficiently low filler loading (e.g., at least about 0.1 wt %, but not more than about 5 wt %) of carbon nanostructured (CNS) filler within a liquid crystal polymer (LCP) matrix, such that the carbon nanostructured filler does not significantly change the rheological or mechanical properties of the matrix into which it is incorporated, and / or the density of the matrix remains substantially unchanged despite the addition of the carbon nanostructured filler. Advantageously, the EMI absorbers and EMI absorbing compositions disclosed herein can provide design flexibility, allowing for the incorporation of effective electromagnetic shielding without significantly increasing the size or weight of the aerospace connector.

[0014] Exemplary embodiments of the EMI absorber and EMI absorbing compositions disclosed herein can also be used with high-speed connectors. For example, exemplary embodiments of the EMI absorber and EMI absorbing compositions disclosed herein can be used with high-speed connectors for server backplanes, Peripheral Component Interconnect Express (PCIe), and the like, which are moving to higher speeds with noise in the 60 GHz range. Additional applications in which exemplary embodiments of the EMI absorber and EMI absorbing compositions disclosed herein can be used include telecommunications infrastructure, wireless networks, satellite communications, security, and defense.

[0015] 1 illustrates an injection-moldable thermoplastic EMI absorber pellet 100 including a carbon nanostructure (CNS) filler (e.g., about 1.5 weight percent) within a liquid crystal polymer (LCP) matrix according to an exemplary embodiment of the present disclosure. The pellet can be injection molded to form an EMI absorber having a one-piece monolithic structure.

[0016] In an exemplary embodiment, a high-temperature injection-moldable thermoplastic EMI absorber includes approximately 1.5 weight percent carbon nanostructure (CNS) filler within a liquid crystal polymer (LCP) matrix. Due to the advantages of the LCP resin system, the EMI absorber has good high-temperature resistance, high dimensional stability, and a low coefficient of thermal expansion. In such an exemplary embodiment, the EMI absorber may provide or include one or more (but not necessarily any or all) of the following features and advantages: injection moldable (ideal for complex shapes), cost-effective for mass production, excellent temperature stability, RoHS compliant, halogen-free per IEC-61249-2-21 standard, and low outgassing. Also, in such an exemplary embodiment, the EMI absorber may be configured to have the following properties: dark gray color, approximately 10 5 A volume resistivity of ohm-centimeter (Ω-cm), a tensile strength of about 70 megapascals (MPa), a tensile elongation of about 1.5 percent, a notched Izod impact strength of about 75 joules per meter (J / m), a flexural strength of 140 MPa, a flexural modulus of about 9 gigapascals (GPa), a mold shrinkage parallel to the flow of about 0.1 percent, a mold shrinkage transverse to the flow of about 0.8 percent, and a UL V0 flammability rating. 5 The volume resistivity in Ω·cm is relatively high at a CNS loading of 1.5 weight percent. Higher CNS loadings would make the absorber even more conductive.

[0017] 2 and 3 include line graphs of dielectric constant versus frequency from 18 gigahertz (GHz) to 40 GHz for six EMI absorbers having different carbon nanostructure (CNS) filler loadings (0.5, 0.7, 0.8, 0.9, 1, and 1.5 weight percent CNS) within a liquid crystal polymer (LCP) matrix according to exemplary embodiments of the present disclosure. As shown in FIGS. 2 and 3, the EMI absorber with the highest CNS loading of 1.5 weight percent had the highest dielectric constant in the frequency range from 18 GHz to 40 GHz. Conversely, the EMI absorber with the lowest CNS loading of 0.5 weight percent had the lowest dielectric constant in the frequency range from 18 GHz to 40 GHz.

[0018] In an exemplary embodiment, the matrix can include at least about 80% but not more than about 90% by weight of the liquid crystal polymer. The matrix can include at least about 10% but not more than about 20% by weight of one or more additives, including glass reinforcement.

[0019] In an exemplary embodiment, an electromagnetic interference (EMI) absorber includes a carbon nanostructured filler within a matrix, the matrix including a liquid crystal polymer, and the EMI absorber includes at least about 0.1 wt % but not more than about 5 wt % of the carbon nanostructured filler within the matrix.

[0020] In exemplary embodiments, an EMI absorber may be configured for use in aerospace applications, such as aerospace connectors. For example, an aerospace connector may include an EMI absorber disclosed herein operatively configured to help maintain the signal integrity of the aerospace connector by reducing or eliminating electromagnetic interference that could degrade the performance or cause malfunction of the aerospace connector, help ensure compliance with regulatory standards for electromagnetic compatibility (EMC) of the aerospace connector by minimizing susceptibility to electromagnetic radiation and external interference, and / or help improve the reliability of the aerospace connector by protecting electronic components from damage or malfunction caused by electromagnetic interference. However, the EMI absorbers disclosed herein may be used in other applications, industries, components, etc., and therefore, the EMI absorbers disclosed herein should not be limited to use only with aerospace connectors. For example, the EMI absorbers disclosed herein may be used with high-speed connectors for server backplanes, Peripheral Component Interconnect Express (PCIe), etc., which are moving to higher speeds with noise in the 60 GHz range. Further applications in which exemplary embodiments of the EMI absorbers and EMI absorbing compositions disclosed herein may be used include telecommunications infrastructure, wireless networks, satellite communications, security and defense, and the like.

[0021] In an exemplary embodiment, the EMI absorber comprises an injection-moldable thermoplastic pellet comprising a matrix comprising a liquid crystal polymer and at least about 1.5 weight percent of a carbon nanostructured filler within the matrix. In such an exemplary embodiment, the injection-moldable thermoplastic pellet absorber is RoHS compliant, halogen-free according to the IEC-61249-2-21 standard, and has a EMI density of at least about 10^5 or 10 5 It can have a volume resistivity of ohm-centimetre.

[0022] In an exemplary embodiment, the EMI absorber comprises at least about 1.5 weight percent carbon nanostructured fillers within a matrix. 5 It may have a volume resistivity of ohm-centimetre.

[0023] In an exemplary embodiment, the EMI absorber comprises at least about 0.5 weight percent but not more than about 3 weight percent carbon nanostructured filler within a matrix. In an exemplary embodiment, the EMI absorber comprises at least about 0.5 weight percent but not more than about 1.5 weight percent carbon nanostructured filler within a matrix.

[0024] In exemplary embodiments, the EMI absorber includes about 0.5, 0.7, 0.8, 0.9, or 1 weight percent carbon nanostructured filler within a matrix. In an exemplary embodiment, the EMI absorber comprises about 0.75 weight percent carbon nanostructured filler within a matrix.

[0025] In an exemplary embodiment, the EMI absorber comprises about 1 weight percent carbon nanostructured filler within a matrix. In an exemplary embodiment, the EMI absorber comprises at least about 95 weight percent but not more than about 99.9 weight percent matrix.

[0026] In an exemplary embodiment, the EMI absorber comprises at least about 0.5 weight percent but not more than about 3 weight percent carbon nanostructured filler within a matrix and at least about 97 weight percent but not more than about 99.5 weight percent matrix.

[0027] In an exemplary embodiment, the EMI absorber comprises at least about 0.5 weight percent but not more than about 1 weight percent carbon nanostructured filler within a matrix and at least about 99 weight percent but not more than about 99.5 weight percent matrix.

[0028] In an exemplary embodiment, the EMI absorber comprises about 0.5 weight percent carbon nanostructure filler within a matrix and about 99.5 weight percent matrix. In an exemplary embodiment, the EMI absorber comprises about 0.75 weight percent carbon nanostructure filler within a matrix and about 99.25 weight percent matrix.

[0029] In an exemplary embodiment, the EMI absorber comprises about 1 weight percent carbon nanostructure filler within a matrix and about 99 weight percent matrix. In exemplary embodiments, the carbon nanostructured filler comprises one or more of the following carbon nanostructures: multi-walled carbon nanotubes in a matrix; single-walled carbon nanotubes in a matrix; and / or a branched network of cross-linked carbon nanotube structures in a matrix.

[0030] In an exemplary embodiment, the EMI absorber comprises a composition comprising a matrix comprising a liquid crystal polymer and at least about 0.1 weight percent but not more than about 5 weight percent of a carbon nanostructured filler within the matrix, which provides a filler loading level of the carbon nanostructured filler within the matrix low enough to allow the carbon nanostructured filler to be well mixed within the matrix, resulting in low viscosity and good flowability for easy injection, casting, or molding of the composition into shapes or patterns.

[0031] In an exemplary embodiment, the EMI absorber includes carbon nanostructured fillers within a matrix at a sufficiently low filler loading level such that the EMI absorber is lightweight. In an exemplary embodiment, the EMI absorber comprises carbon nanostructured fillers at a sufficiently low filler loading level within the matrix such that the carbon nanostructured fillers do not significantly alter the rheological or mechanical properties of the matrix in which they are incorporated.

[0032] In exemplary embodiments, the EMI absorber includes a carbon nanostructured filler at a sufficiently low filler loading level within the matrix such that the density of the matrix remains substantially unchanged after the carbon nanostructured filler is incorporated into the matrix. For example, the density of the control (matrix without CNS filler) was 1.5772. The density of the matrix incorporated with 0.25 weight percent carbon nanostructured filler was 1.5758. The density of the matrix incorporated with 0.5 weight percent carbon nanostructured filler was 1.5871. The density of the matrix incorporated with 1 weight percent carbon nanostructured filler was 1.5562. These densities are merely examples, and other exemplary embodiments may be configured to have higher or lower densities.

[0033] In an exemplary embodiment, the EMI absorber is configured to be operable with an attenuation of at least 20 decibels per centimeter (dB / cm) at frequencies between about 18 gigahertz (GHz) and about 60 GHz. For example, the EMI absorber may be configured to be operable with an attenuation of at least 20 dB / cm at frequencies between about 18 gigahertz (GHz) and about 60 GHz at 0 and 90 degree orientations.

[0034] In exemplary embodiments, the EMI absorber includes one or more additives, non-additive fillers, and / or glass reinforcement in a matrix. For example, the matrix may include at least about 10 weight percent, but not more than about 20 weight percent, of one or more additives, including glass reinforcement.

[0035] In an exemplary embodiment, the EMI absorber comprises a thermoplastic injection moldable pellet. The EMI absorber may be an injection molded EMI absorber having a one-piece monolithic structure.

[0036] Also disclosed are exemplary compositions for electromagnetic interference (EMI) absorbers. In exemplary embodiments, the compositions include carbon nanostructured fillers within a matrix. The matrix includes a liquid crystal polymer. The compositions also include at least about 0.1 weight percent to about 5 weight percent of the carbon nanostructured fillers.

[0037] In exemplary embodiments, compositions may be configured for use in aerospace applications, such as aerospace connectors. For example, an aerospace connector may include an EMI absorber disclosed herein operatively configured to help maintain the signal integrity of the aerospace connector by reducing or eliminating electromagnetic interference that can degrade the performance or cause malfunction of the aerospace connector, and / or help ensure compliance of the aerospace connector with regulatory standards for electromagnetic compatibility (EMC) by minimizing susceptibility to electromagnetic radiation and external interference, and / or help improve the reliability of the aerospace connector by protecting electronic components from damage or malfunction caused by electromagnetic interference. However, the compositions disclosed herein may be used in other applications, industries, components, etc., and therefore, the compositions disclosed herein should not be limited to use only with aerospace connectors. For example, the compositions disclosed herein may be used with high-speed connectors for server backplanes, Peripheral Component Interconnect Express (PCIe), and the like, which are migrating to higher speeds with noise in the 60 GHz range. Additional applications in which exemplary embodiments of the compositions disclosed herein may be used include telecommunications infrastructure, wireless networks, satellite communications, security and defense, and the like.

[0038] In an exemplary embodiment, the composition comprises at least about 0.5 weight percent but not more than about 3 weight percent carbon nanostructured filler within the matrix. In an exemplary embodiment, the composition is RoHS compliant, halogen-free according to the IEC-61249-2-21 standard, and has a pH of at least about 105 It can have a volume resistivity of ohm-centimetre.

[0039] In an exemplary embodiment, the composition comprises at least about 0.5 weight percent but not more than about 1.5 weight percent of carbon nanostructured filler within the matrix. In exemplary embodiments, the composition comprises about 0.5, 0.7, 0.8, 0.9, or 1 weight percent carbon nanostructured filler within the matrix.

[0040] In an exemplary embodiment, the composition comprises about 0.75 weight percent carbon nanostructured filler within the matrix. In an exemplary embodiment, the composition comprises about 1 weight percent carbon nanostructured filler within the matrix.

[0041] In an exemplary embodiment, the composition comprises at least about 95 weight percent but not more than about 99.9 weight percent matrix. In an exemplary embodiment, the composition comprises at least about 0.5 weight percent but not more than about 3 weight percent carbon nanostructured filler in a matrix and at least about 97 weight percent but not more than about 99.5 weight percent matrix.

[0042] In an exemplary embodiment, the composition comprises at least about 0.5 weight percent but not more than about 1 weight percent carbon nanostructured filler in a matrix and at least about 99 weight percent but not more than about 99.5 weight percent matrix.

[0043] In an exemplary embodiment, the composition comprises about 0.5 weight percent carbon nanostructured filler within a matrix and about 99.5 weight percent matrix. In an exemplary embodiment, the composition comprises about 0.75 weight percent carbon nanostructured filler within the matrix and about 99.25 weight percent matrix.

[0044] In an exemplary embodiment, the composition comprises about 1 weight percent carbon nanostructured filler within a matrix and about 99 weight percent matrix. In exemplary embodiments, the carbon nanostructured filler comprises one or more of the following carbon nanostructures: multi-walled carbon nanotubes in a matrix; single-walled carbon nanotubes in a matrix; and / or a branched network of cross-linked carbon nanotube structures in a matrix.

[0045] In an exemplary embodiment, the composition comprises a sufficiently low filler loading level of carbon nanostructured filler within the matrix that allows the carbon nanostructured filler to be thoroughly mixed within the matrix, resulting in low viscosity and good flowability for easy pouring, casting, or molding of the composition into shapes or patterns.

[0046] In an exemplary embodiment, the composition includes a carbon nanostructured filler at a sufficiently low filler loading level within the matrix such that the composition is lightweight. In an exemplary embodiment, the composition comprises a sufficiently low filler loading level of carbon nanostructured filler within the matrix such that the carbon nanostructured filler does not significantly alter the rheological or mechanical properties of the matrix in which it is incorporated.

[0047] In an exemplary embodiment, the composition includes a sufficiently low filler loading level of carbon nanostructured filler within the matrix such that the density of the matrix remains substantially unchanged after the carbon nanostructured filler is incorporated into the matrix.

[0048] In an exemplary embodiment, the composition is configured to be operable with an attenuation of at least 20 decibels per centimeter (dB / cm) at frequencies between about 18 gigahertz (GHz) and about 60 GHz. For example, the composition may be configured to be operable with an attenuation of at least 20 dB / cm at frequencies between about 18 gigahertz (GHz) and about 60 GHz at 0 and 90 degree orientations.

[0049] In an exemplary embodiment, the composition includes one or more additives, non-additive fillers, and / or glass reinforcement in a matrix. For example, the matrix may include at least about 10 weight percent, but not more than about 20 weight percent, of one or more additives, including glass reinforcement.

[0050] In an exemplary embodiment, the composition is injection moldable. The composition may include thermoplastic injection moldable pellets. EMI absorbers may also be injection molded from the composition. The exemplary embodiments are provided so that this disclosure will be thorough and will fully convey the scope to those skilled in the art. Numerous specific details are set forth, such as examples of specific components, devices, and methods, to provide a thorough understanding of the embodiments of the present disclosure. It will be apparent to those skilled in the art that the use of specific details is not necessary, that the exemplary embodiments can be embodied in many different forms, and that neither should be construed as limiting the scope of the present disclosure. In some exemplary embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. Furthermore, advantages and improvements that may be achieved in one or more exemplary embodiments of the present disclosure are provided for illustrative purposes only and do not limit the scope of the present disclosure, as an exemplary embodiment of the present disclosure may provide all or none of the above advantages and improvements and still be within the scope of the present disclosure.

[0051] The specific dimensions, specific materials, and / or specific shapes disclosed herein are exemplary in nature and do not limit the scope of the present disclosure. The disclosure herein of a specific value and a specific range of values ​​for a given parameter does not exclude other values ​​and ranges of values ​​that may be useful in one or more examples disclosed herein. Furthermore, it is contemplated that any two specific values ​​for a particular parameter described herein may define the endpoints of a range of values ​​that may be suitable for the given parameter (i.e., the disclosure of a first value and a second value for a given parameter can be interpreted as disclosing that any value between the first and second values ​​can be used for the particular parameter). For example, if parameter X is exemplified herein as having a value A and also as having a value Z, it is contemplated that parameter X may have a range of values ​​from about A to about Z. Similarly, the disclosure of two or more ranges of values ​​for a parameter (whether such ranges are nested, overlapping, or separate) is contemplated to encompass all possible combinations of ranges of values ​​that may be claimed using the endpoints of the disclosed ranges. For example, if a parameter X is exemplified herein as having a value in the range of 1 to 10, or 2 to 9, or 3 to 8, it is also contemplated that the parameter X may have other ranges of values, including 1 to 9, 1 to 8, 1 to 3, 1 to 2, 2 to 10, 2 to 8, 2 to 3, 3 to 10, and 3 to 9.

[0052] The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. For example, when permissive phrases such as "may include" or "may include" are used herein, at least one embodiment includes the feature. As used herein, the singular forms "a," "an," and "the" may be intended to include the plural forms as well, unless the context clearly dictates otherwise. The terms "comprise," "include," and "have" are inclusive and thus specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Method steps, processes, and operations described herein should not be construed as necessarily requiring their performance in the particular order described or illustrated, unless specifically identified as an order of performance. It should also be understood that additional or alternative steps may be employed.

[0053] When an element or layer is described as "on," "engaged with," "connected to," or "bonded to" another element or layer, it may be directly on, engaged with, connected to, or bonded to that other element or layer, or to intervening elements or layers that may be present. In contrast, when an element is described as "directly on," "directly engaged with," "directly connected to," or "directly bonded to" another element or layer, there may be no intervening elements or layers. Other words used to describe relationships between elements should be interpreted in a similar manner (e.g., "between" and "directly between," "adjacent" and "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0054] The term "about," when applied to a value, indicates that the calculation or measurement allows for slight imprecision in the value (approximately or reasonably close to the value, depending on the approach to the accuracy of the value; approximately). If, for some reason, the imprecision provided by "about" is not understood in this ordinary sense in the art, "about," as used herein, refers to at least the variation that can result from ordinary methods of measuring or using such parameters. For example, the terms "generally," "about," and "substantially" can be used herein to mean within manufacturing tolerances. Alternatively, for example, the term "about," when used herein when modifying the amounts of components or reactants of the present invention, refers to variations in numerical values ​​that can occur, for example, in typical measuring and handling procedures used in producing concentrates or solutions in the real world, through inadvertent errors in these procedures, or through differences in the manufacture, source, or purity of components used to make the composition or carry out the method. The term "about" also encompasses amounts that differ due to different equilibrium conditions of a composition resulting from a particular initial mixture. Numerical quantities and equivalent amounts are included regardless of whether they are modified by the term "about."

[0055] Terms such as "first," "second," and "third" may be used herein to describe various elements, components, regions, layers, and / or sections, but these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer, or section from another region, layer, or section. When used herein, terms such as "first," "second," and other numerical terms do not imply an order or sequence unless clearly indicated by context. Thus, a first element, component, region, layer, or section discussed below could be referred to as a second element, component, region, layer, or section without departing from the teachings of the exemplary embodiments.

[0056] Spatially relative terms such as "inside," "outside," "below," "down," "lower," "upper," "above," and the like may be used herein to facilitate the description of the relationship of one element or feature to another, as shown in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. For example, if the device in the figures is turned over, elements described as "below" or "below" other elements or features would then become "above" the other elements or features. Thus, the example term "below" can encompass both an orientation of above and below. The device may be oriented differently (rotated 90 degrees or in another orientation), and the spatially relative descriptors used herein may be interpreted accordingly.

[0057] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements, intended or described uses, or features of a particular embodiment are in most cases not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in selected embodiments even if not specifically shown or described. The same can also be modified in many ways. Such modifications should not be considered a departure from the disclosure, and all such variations are intended to be included within the scope of the disclosure.

Claims

1. 1. An electromagnetic interference (EMI) absorber comprising carbon nanostructured fillers within a matrix, the matrix comprises a liquid crystal polymer; The EMI absorber comprises at least about 0.1 weight percent but not more than about 5 weight percent of carbon nanostructured fillers within the matrix.

2. 10. The EMI absorber of claim 1, wherein the EMI absorber comprises an injection moldable thermoplastic pellet comprising the matrix including the liquid crystal polymer and at least about 1.5 weight percent of a carbon nanostructured filler within the matrix.

3. The injection moldable thermoplastic pellets are RoHS compliant, halogen-free according to IEC-61249-2-21 standard, and have a solubility of at least about 10 ５ 3. The EMI absorber of claim 2 having a volume resistivity of ohm-centimeters.

4. 10. The EMI absorber of claim 1, comprising at least about 1.5 weight percent of said carbon nanostructured filler within said matrix.

5. At least about 10 ５ 5. The EMI absorber of claim 4 having a volume resistivity of ohm-centimeters.

6. 10. The EMI absorber of claim 1, comprising at least about 0.5 weight percent but not more than about 3 weight percent of said carbon nanostructured filler within said matrix.

7. 10. The EMI absorber of claim 1, comprising at least about 0.5 weight percent but not more than about 1.5 weight percent of said carbon nanostructured filler within said matrix.

8. 10. The EMI absorber of claim 1 comprising about 0.5, 0.7, 0.8, 0.9, or 1 weight percent of said carbon nanostructured filler within said matrix.

9. The carbon nanostructure filler is multi-walled carbon nanotubes within the matrix; Single-walled carbon nanotubes within the matrix, and / or a carbon nanostructure comprising a branched network of bridged carbon nanotube structures within the matrix; 10. The EMI absorber of claim 1, comprising one or more of:

10. 10. The EMI absorber of claim 1, wherein the EMI absorber comprises a composition comprising the matrix comprising the liquid crystal polymer and at least about 0.1 weight percent but not more than about 5 weight percent of the carbon nanostructured filler within the matrix, such that the filler loading level of the carbon nanostructured filler within the matrix is ​​low enough to allow the carbon nanostructured filler to be well mixed within the matrix, resulting in low viscosity and good flowability for easy injection, casting, or molding of the composition into shapes or patterns.

11. 10. The EMI absorber of claim 1, configured to be operable with an attenuation rate of at least 20 decibels per centimeter (dB / cm) at frequencies between about 18 gigahertz (GHz) and about 60 GHz.

12. the EMI absorber is configured to be operable with an attenuation of at least 20 dB / cm at frequencies between about 18 gigahertz (GHz) and about 60 GHz at 0-degree and 90-degree orientations; and the EMI absorber comprises at least about 0.5 weight percent but not more than about 3 weight percent of the carbon nanostructure filler in the matrix and at least about 97 weight percent but not more than about 99.5 weight percent of the matrix; or 10. The EMI absorber of claim 1, wherein the EMI absorber comprises at least about 0.5 weight percent but not more than about 1 weight percent of the carbon nanostructured filler within the matrix and at least about 99 weight percent but not more than about 99.5 weight percent of the matrix.

13. 13. The EMI absorber of any one of claims 1 to 12, wherein the EMI absorber comprises an injection moldable thermoplastic pellet made from the matrix comprising the liquid crystal polymer and the carbon nanostructured filler within the matrix.

14. The injection moldable thermoplastic pellets are RoHS compliant, halogen-free according to IEC-61249-2-21 standard, and have a solubility of at least about 10 ５ 14. The EMI absorber of claim 13 having a volume resistivity of ohm-centimeters.

15. 13. The EMI absorber of any one of claims 1 to 12, wherein the EMI absorber comprises an injection-moldable EMI-absorbing composition comprising the matrix including the liquid crystal polymer and the carbon nanostructure filler within the matrix.

16. 13. The EMI absorber of any one of claims 1 to 12, wherein the EMI absorber is injection molded to have an integral monolithic structure from a composition comprising the matrix including the liquid crystal polymer and the carbon nanostructured filler within the matrix.

17. 13. The EMI absorber of any one of claims 1 to 12, wherein the matrix comprises at least about 10 weight percent but not more than about 20 weight percent of one or more additives including glass reinforcement.

18. An aerospace connector comprising the EMI absorber according to any one of claims 1 to 12, Help maintain the signal integrity of the aerospace connector by reducing or eliminating electromagnetic interference that may degrade the performance or cause malfunction of the aerospace connector; and / or Help ensure compliance of the aerospace connector with regulatory standards for electromagnetic compatibility (EMC) by minimizing electromagnetic radiation and susceptibility to external interference; and / or 1. An aerospace connector configured to be operable to help improve reliability of said aerospace connector by protecting electronic components from damage or malfunction caused by electromagnetic interference.

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