Circuit structure

Abstract

A circuit structure is provided that includes a substrate and one or more conductive elements disposed on the substrate. The substrate includes a polymer composition having a conductive filler distributed within a polymer matrix. The polymer matrix contains at least one thermoplastic high-performance polymer that has a deflection under load of about 40°C or greater, as determined in accordance with ISO 75-2:2013 at a load of 1.8 MPa. The polymer composition exhibits a dielectric constant of about 4 or greater and a dissipation factor of about 0.3 or less, as determined at a frequency of 2 GHz.

Description

[Technical Field]

[0001] Cross-reference of related questions

[0001] This application claims the benefit of U.S. Provisional Patent Applications Nos. 62 / 981,667 (filed February 26, 2020), 62 / 981,681 (filed February 26, 2020), 63 / 057,345 (filed July 28, 2020), and 63 / 057,349 (filed July 28, 2020), which are incorporated herein by reference in their entireties. [Background technology]

[0002] Molded circuit devices (MIDs) are three-dimensional electromechanical devices that typically contain plastic components and electronic circuit traces. A plastic substrate is fabricated, and electrical circuits and devices are plated, laminated, or embedded into the plastic substrate. MIDs typically contain fewer components than traditionally produced devices, resulting in space and weight savings. Current methods for manufacturing MIDs include two-shot molding and laser direct structuring. Laser direct structuring, for example, involves the use of spinel crystals (e.g., copper chromite) to act as seeds to initiate metallization of the substrate. After forming the metal layer, a laser etches a wiring pattern onto the component, preparing it for metallization. Despite its benefits, one limitation of laser direct structuring materials is that spinel crystals tend to adversely affect the performance of the composition at high frequencies often encountered in antenna systems. Therefore, there is currently a need for improved polymer substrates that are plateable and still retain good performance in the high-frequency range. Summary of the Invention [Means for solving the problem]

[0003] According to one embodiment of the present invention, a circuit structure is disclosed that includes a substrate and one or more conductive elements disposed on the substrate. The substrate includes a polymer composition including a conductive filler distributed within a polymer matrix. The polymer matrix contains at least one thermoplastic high-performance polymer that has a deflection under load of about 40°C or greater, as determined in accordance with ISO 75-2:2013 at a load of 1.8 MPa. The polymer composition exhibits a dielectric constant of about 4 or greater and a dissipation factor of about 0.3 or less, as determined at a frequency of 2 GHz.

[0004]

[0003] Other features and aspects of the present invention are described in more detail below. A full and enabling disclosure of the present invention, including the best mode thereof to one skilled in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0005] [Figure 1]

[0005] FIG. 1 is a front perspective view of one embodiment of an electronic component that can utilize the antenna system. [Figure 2] FIG. 1 is a rear perspective view of one embodiment of an electronic component that can utilize the antenna system. [Figure 3]

[0006] FIG. 2 is a top view of an exemplary inverted-F antenna resonating element of one embodiment of an antenna system. [Figure 4]

[0007] FIG. 2 is a top view of an exemplary monopole antenna resonating element of one embodiment of an antenna system. [Figure 5]

[0008] FIG. 2 is a top view of an exemplary slot antenna resonating element of one embodiment of an antenna system. [Figure 6]

[0009] FIG. 2 is a top view of an exemplary patch antenna resonating element of one embodiment of an antenna system. [Figure 7]

[0010] 1 is a top view of an exemplary multi-branch inverted-F antenna resonating element of one embodiment of an antenna system. FIG. [Figure 8]

[0011] 1 illustrates a 5G antenna system including a base station, one or more relay stations, one or more user computing devices, and one or more Wi-Fi repeaters, according to an embodiment of the present disclosure. [Figure 9A]

[0012] 1 illustrates a top view of an exemplary user computing device including a 5G antenna according to an embodiment of the present disclosure. [Figure 9B]

[0013] 9B illustrates a side elevation view of the example user computing device of FIG. 9A including a 5G antenna according to an embodiment of the present disclosure. [Figure 10]

[0014] 9B shows an expanded view of a portion of the user computing device of FIG. 9A. [Figure 11]

[0015] FIG. 1 illustrates a side elevation view of a coplanar waveguide antenna array configuration according to an aspect of the present disclosure. [Figure 12A]

[0016] 1 illustrates an antenna array in a large scale multiple-input multiple-output configuration according to an aspect of the present disclosure. [Figure 12B]

[0017] 1 illustrates an antenna array formed by laser direct structuring, according to an aspect of the present disclosure. [Figure 12C]

[0018] 1 illustrates an exemplary antenna configuration according to an aspect of the present disclosure. [Figure 13]

[0019] 1A-1C show simplified sequential diagrams of a laser direct structuring manufacturing process that can be used to form the antenna system. DETAILED DESCRIPTION OF THE INVENTION

[0006]

[0020] It will be understood by those skilled in the art that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of the invention.

[0021] Generally, the present invention relates to a circuit structure containing a substrate and one or more conductive elements disposed thereon. The substrate comprises a polymeric composition including a conductive filler, the conductive filler being distributed within a polymeric matrix comprising a high-performance thermoplastic polymer. By selectively controlling various aspects of the composition, the inventors have discovered that the resulting composition can maintain a unique combination of high dielectric constant and low dissipation factor for use in various types of electronic components, such as antenna systems. For example, the polymeric composition may exhibit a high dielectric constant of about 4 or greater, in some embodiments about 5 or greater, in some embodiments about 6 or greater, in some embodiments about 8 to about 30, in some embodiments about 10 to about 25, and in some embodiments about 12 to about 24, as determined by split post resonance at a frequency of 2 GHz. Such a high dielectric constant facilitates the ability to form thin substrates and can further enable the utilization of multiple conductive elements (e.g., antennas) operating simultaneously with only minimal levels of electrical interference. The dielectric dissipation factor, a measure of the rate of energy loss, may also be relatively low, e.g., about 0.3 or less, in some embodiments about 0.2 or less, in some embodiments about 0.1 or less, in some embodiments about 0.06 or less, in some embodiments about 0.04 or less, and in some embodiments about 0.001 to about 0.03, as determined by the split post resonance method at a frequency of 2 GHz. The inventors have also discovered that the dielectric constant and dielectric dissipation factor can be maintained within the above-mentioned ranges even when exposed to various temperatures, such as temperatures from about -30°C to about 100°C. For example, when subjected to the thermal cycling test described herein, the ratio of the dielectric constant to the initial dielectric constant after thermal cycling may be about 0.8 or more, in some embodiments about 0.9 or more, and in some embodiments about 0.95 to about 1.1. Similarly, the ratio of the dissipation factor after exposure to elevated temperatures to the initial dissipation factor may be about 1.3 or less, in some embodiments about 1.2 or less, in some embodiments about 1.1 or less, in some embodiments about 1.0 or less, in some embodiments 0.95 or less, in some embodiments from about 0.1 to about 0.95, and in some embodiments, from about 0.2 to about 0.9.The change in dissipation factor (i.e., initial dissipation factor minus dissipation factor after thermal cycling) may also range from about −0.1 to about 0.1, in some embodiments from about −0.05 to about 0.01, and in some embodiments, from about −0.001 to 0.

[0007]

[0022] It has traditionally been thought that polymer compositions having a combination of high dielectric constant and low dielectric loss tangent do not simultaneously possess sufficiently high electrical conductivity to enable metallization of a substrate. However, the present inventors have discovered that polymer compositions can exhibit controlled resistivity that generally allows them to remain essentially antistatic, so that substantial amounts of current do not flow through the component, yet still exhibit a sufficient degree of electrostatic dissipation to facilitate plating and the formation of conductive traces thereon. Surface resistivities can be, for example, about 1×10, as determined, for example, according to ASTM D257-14 (technically equivalent to IEC 62631-3-1). 12 ohm ~ approx. 1 x 10 18 ohms, in some embodiments, approximately 1×10 13 ohm ~ approx. 1 x 10 18 ohms, in some embodiments, approximately 1×10 14 ohm ~ approx. 1 x 10 17 ohms, in some embodiments, approximately 1×10 15 ohm ~ approx. 1 x 10 17 Similarly, the composition may also have a viscosity in the range of about 1×10 ohms, determined at a temperature of about 20° C., for example, according to ASTM D257-14 (technically equivalent to IEC 62631-3-1). 10 ohm·m ~ approx. 1×10 16 ohm m, in some embodiments, approximately 1 x 10 11 ohm·m ~ approx. 1×10 16 ohm m, in some embodiments, approximately 1 x 10 12 ohm·m ~ approx. 1×10 15 ohm m, in some embodiments, approximately 1 x 10 13 ohm·m ~ approx. 1×10 15 It may also be expressed as volume resistivity in ohm·m.

[0008]

[0023] The polymer compositions of the present invention may also have excellent strength properties. For example, the compositions may have a strength of about 2 kJ / m2 as measured according to ISO Test No. 179-1:2010 at 23°C. 2 and in some embodiments, from about 4 to about 40 kJ / m 2 and in some embodiments, from about 6 to about 30 kJ / m 2 The compositions may also exhibit unnotched and / or notched Charpy impact strengths of from about 20 to about 500 MPa, and in some embodiments, from about 50 to about 400 MPa, and in some embodiments, from about 60 to about 350 MPa; a tensile strain at break of at least about 0.5%, and in some embodiments, from about 0.8% to about 15%, and in some embodiments, from about 1% to about 10%; and / or a tensile modulus of from about 5,000 MPa to about 30,000 MPa, and in some embodiments, from about 7,000 MPa to about 25,000 MPa, and in some embodiments, from about 10,000 MPa to about 20,000 MPa. Tensile properties may be determined according to ISO Test No. 527:2019 at 23°C. The compositions may also exhibit a flexural strength of about 40 to about 500 MPa, in some embodiments about 50 to about 400 MPa, and in some embodiments about 100 to about 350 MPa; a flexural break strain of about 0.5% or greater, in some embodiments about 0.8% to about 15%, and in some embodiments about 1% to about 10%; and / or a flexural modulus of about 7,000 MPa or greater, in some embodiments about 9,000 MPa or greater, in some embodiments about 10,000 MPa to about 30,000 MPa, and in some embodiments about 12,000 MPa to about 25,000 MPa. Flexural properties may be determined according to ISO Test No. 178:2019 at 23°C.

[0009]

[0024] As noted above, one benefit of the present invention is that substrates formed from polymeric compositions can be readily plated without the use of conventional laser-activatable spinel crystals, which generally have the formula AB2O4, where A is a metal cation having a valence of 2 (e.g., cadmium, chromium, manganese, nickel, zinc, copper, cobalt, iron, magnesium, tin, or titanium) and B is a metal cation having a valence of 3 (e.g., chromium, iron, aluminum, nickel, manganese, or tin). Generally, A in the above formula provides the major cation component of the first metal oxide cluster, and B provides the major cation component of the second metal oxide cluster. For example, the first metal oxide cluster generally has a tetrahedral structure, and the second metal oxide cluster generally has an octahedral cluster. Specific examples of such spinel crystals include, for example, MgAl2O4, ZnAl2O4, FeAl2O4, CuFe2O4, CuCr2O4, MnFe2O4, NiFe2O4, TiFe2O4, FeCr2O4, or MgCr2O4. The polymer composition may be free of such spinel crystals (i.e., 0 wt.%), or such crystals may be present in only trace concentrations, such as about 1 wt.% or less, in some embodiments about 0.5 wt.% or less, and in some embodiments, in an amount of about 0.001 wt.% to about 0.2 wt.%.

[0010]

[0025] Various embodiments of the invention will now be described in more detail. I. Polymer Composition A. Polymer matrix

[0026] The polymer matrix generally contains one or more thermoplastic high performance polymers in an amount of about 30 wt.% to about 80 wt.%, in some embodiments about 40 wt.% to about 75 wt.%, and in some embodiments about 50 wt.% to about 70 wt.% of the total polymer composition. The high performance polymers may have a high degree of heat resistance, as reflected by a deflection temperature under load ("DTUL") of about 40°C or greater, in some embodiments about 50°C or greater, in some embodiments about 60°C or greater, in some embodiments about 100°C to about 320°C, in some embodiments about 150°C to about 310°C, and in some embodiments about 220°C to about 300°C, as determined according to ISO 75-2:2013 at a load of 1.8 MPa. In addition to exhibiting a high degree of heat resistance, the polymers also typically have high glass transition temperatures, such as about 40° C. or higher, in some embodiments about 50° C. or higher, in some embodiments about 60° C. or higher, in some embodiments about 70° C. or higher, in some embodiments about 80° C. or higher, and in some embodiments, from about 100° C. to about 320° C. When semi-crystalline or crystalline polymers are utilized, the high performance polymers may also have high melting temperatures, such as about 140° C. or higher, in some embodiments about 150° C. to about 420° C., in some embodiments about 200° C. to about 410° C., and in some embodiments, about 300° C. to about 400° C. Glass transition and melting temperatures may be determined as known in the art using differential scanning calorimetry ("DSC"), for example, by ISO 11357-2:2020 (glass transition) and 11357-3:2018 (melting).

[0011]

[0027] Suitable high performance thermoplastic polymers for this purpose may include, for example, polyamides (e.g., aliphatic, semi-aromatic, or aromatic polyamides), polyesters, polyarylene sulfides, liquid crystal polymers (e.g., wholly aromatic polyesters, polyesteramides, etc.), polycarbonates, polyphenylene ethers, polyphenylene oxides, polyimides (e.g., polyetherimides), etc., and blends thereof. The exact selection of the polymer system will depend on various factors, such as the nature of any other fillers included in the composition, the manner in which the composition is formed and / or processed, and the particular requirements of the intended application.

[0012]

[0028] For example, aromatic polymers are particularly suitable for use in the polymer matrix. The aromatic polymer can be substantially amorphous, semi-crystalline, or crystalline. One example of a suitable semi-crystalline aromatic polymer is, for example, an aromatic polyester, which can be the condensation product of at least one diol (e.g., aliphatic and / or cycloaliphatic) with at least one aromatic dicarboxylic acid, such as one having 4 to 20 carbon atoms, and in some embodiments, 8 to 14 carbon atoms. Suitable diols include, for example, neopentyl glycol, cyclohexanedimethanol, 2,2-dimethyl-1,3-propanediol, and carboxylic acids of the formula HO(CH2). n OH (where n is an integer from 2 to 10). Suitable aromatic dicarboxylic acids include, for example, isophthalic acid, terephthalic acid, 1,2-di(p-carboxyphenyl)ethane, 4,4'-dicarboxydiphenyl ether, and the like, and combinations thereof. Fused rings may be present, as in 1,4-, 1,5-, or 2,6-naphthalenedicarboxylic acid. Specific examples of such aromatic polyesters may include, for example, poly(ethylene terephthalate) (PET), poly(1,4-butylene terephthalate) (PBT), poly(1,3-propylene terephthalate) (PPT), poly(1,4-butylene 2,6-naphthalate) (PBN), poly(ethylene 2,6-naphthalate) (PEN), poly(1,4-cyclohexylene dimethylene terephthalate) (PCT), as well as mixtures of the above.

[0013]

[0029] Derivatives and / or copolymers of aromatic polyesters (e.g., polyethylene terephthalate) may also be utilized. For example, in one embodiment, modifying acids and / or diols may be used to form derivatives of such polymers. As used herein, the terms "modifying acid" and "modifying diol" are intended to define compounds that can form part of the acid and diol repeat units of a polyester, respectively, and that can modify the polyester to reduce its crystallinity or render the polyester amorphous. Examples of modifying acid components may include, but are not limited to, isophthalic acid, phthalic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, suberic acid, 1,12-dodecanedioic acid, and the like. In practice, it is often preferable to use functional acid derivatives of these acids, such as the dimethyl, diethyl, or dipropyl esters of the dicarboxylic acids. Where practical, anhydrides or acid halides of these acids may also be utilized. Examples of modified diol components include, but are not limited to, neopentyl glycol, 1,4-cyclohexanedimethanol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, Z,8-bis(hydroxymethyltricyclo[5. 2.1.0]-decane (where Z represents 3, 4, or 5); 1,4-bis(2-hydroxyethoxy)benzene, 4,4'-bis(2-hydroxyethoxy)diphenyl ether [bis-hydroxyethyl bisphenol A], 4,4'-bis(2-hydroxyethoxy)diphenyl sulfide [bis-hydroxyethyl bisphenol S], and diols containing one or more oxygen atoms in the chain, such as diethylene glycol, triethylene glycol, dipropylene glycol, and tripropylene glycol.Generally, these diols contain from 2 to 18 carbon atoms, and in some embodiments from 2 to 8. The alicyclic diols can be utilized in their cis or trans configuration, or as a mixture of both forms.

[0014]

[0030] Such aromatic polyesters typically have a DTUL value, determined according to ISO 75-2:2013 at a load of 1.8 MPa, of about 40°C to about 80°C, in some embodiments, about 45°C to about 75°C, and in some embodiments, about 50°C to about 70°C. The aromatic polyesters also typically have a glass transition temperature, determined according to, for example, ISO 11357-2:2020, of about 30°C to about 120°C, in some embodiments, about 40°C to about 110°C, and in some embodiments, about 50°C to about 100°C, as well as a melting temperature, determined according to, for example, ISO 11357-2:2018, of about 170°C to about 300°C, in some embodiments, about 190°C to about 280°C, and in some embodiments, about 210°C to about 260°C. The aromatic polyester may also have an intrinsic viscosity, for example, determined according to ISO 1628-5:1998, of from about 0.1 dl / g to about 6 dl / g, in some embodiments from about 0.2 to about 5 dl / g, and in some embodiments, from about 0.3 to about 1 dl / g.

[0015]

[0031] Polyarylene sulfide is also a suitable semi-crystalline aromatic polymer.Polyarylene sulfide may be a homopolymer or copolymer.For example, by selectively combining dihaloaromatic compounds, polyarylene sulfide copolymers containing two or more different units can be produced.For example, when p-dichlorobenzene is used in combination with m-dichlorobenzene or 4,4'-dichlorodiphenyl sulfone, the polyarylene sulfide copolymers of the formula:

[0016] [ka]

[0017] and a segment having the structure of the formula:

[0018] [ka]

[0019] A segment having the structure, or formula:

[0020] [ka]

[0021] It is possible to form a polyarylene sulfide copolymer containing segments having the structure:

[0032] Polyarylene sulfides may be linear, semi-linear, branched, or crosslinked. Linear polyarylene sulfides typically contain 80 mol% or more of the repeating unit -(Ar-S)-. Such linear polymers may also contain a small amount of branching or crosslinking units, but the amount of branching or crosslinking units is typically less than about 1 mol% of the total monomer units of the polyarylene sulfide. Linear polyarylene sulfide polymers may be random copolymers or block copolymers containing the above repeating units. Semi-linear polyarylene sulfides may also have a crosslinked or branched structure in which a small amount of one or more monomers having three or more reactive functional groups are introduced into the polymer. For example, the monomer components used to form semi-linear polyarylene sulfides may include a certain amount of polyhaloaromatic compounds having two or more halogen substituents per molecule, which can be used to prepare branched polymers. Such monomers have the formula R'X nwherein each X is selected from chlorine, bromine, and iodine; n is an integer from 3 to 6; R' is a polyvalent aromatic group of valence n that may have up to about four methyl substituents; and the total number of carbon atoms in R' is in the range of 6 to about 16. Examples of some polyhaloaromatic compounds substituted with more than two halogens per molecule that can be used to form semi-linear polyarylene sulfides include 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, 1,3-dichloro-5-bromobenzene, 1,2,4-triiodobenzene, 1,2,3,5-tetrabromobenzene, hexachlorobenzene, 1,3,5-trichloro-2,4,6-trimethylbenzene, 2,2',4,4'-tetrachlorobiphenyl, 2,2',5,5'-tetra-iodobiphenyl, 2,2',6,6'-tetrabromo-3,3',5,5'-tetramethylbiphenyl, 1,2,3,4-tetrachloronaphthalene, 1,2,4-tribromo-6-methylnaphthalene, and the like, and mixtures thereof.

[0022]

[0033] Such polyarylene sulfides typically have a DTUL value, determined according to ISO 75-2:2013 at a load of 1.8 MPa, of about 70°C to about 220°C, in some embodiments, about 90°C to about 200°C, and in some embodiments, about 120°C to about 180°C. Polyarylene sulfides also typically have a glass transition temperature, determined, for example, according to ISO 11357-2:2020, of about 50°C to about 120°C, in some embodiments, about 60°C to about 115°C, and in some embodiments, about 70°C to about 110°C, as well as a melting temperature, determined, for example, according to ISO 11357-3:2018, of about 220°C to about 340°C, in some embodiments, about 240°C to about 320°C, and in some embodiments, about 260°C to about 300°C.

[0023]

[0034] As noted above, substantially amorphous polymers lacking a distinct melting point temperature may also be utilized. Suitable amorphous polymers may include, for example, aromatic polycarbonates, which typically have the formula -R 1Polycarbonates contain repeating carbonate units of the formula -OC(O)-O-. 1 At least a portion (e.g., 60% or more) of the total number of groups are aromatic in that they contain aromatic moieties, with the remainder being aliphatic, alicyclic, or aromatic. 1 is C 6~30 It may be an aromatic group, i.e., it contains at least one aromatic moiety. Typically, R 1 is the general formula HO-R 1 -OH dihydroxyaromatic compounds, such as those of the specific formulae referenced below: H.O.A. 1 -Y 1 -A 2 -OH (In the formula, A 1 and A 2 are independently a monocyclic divalent aromatic group, Y 1 is a single bond or A 1 and A 2 In one particular embodiment, the dihydroxy aromatic compound is derived from one having the following formula (I):

[0024] [ka]

[0025] (In the formula, R a and R b are each independently a halogen or C 1~12 Alkyl groups, e.g., C arranged meta to the hydroxy group on each arylene group 1~3 an alkyl group (e.g., methyl), p and q are each independently 0 to 4 (e.g., 1); X a represents a bridging group connecting two hydroxy-substituted aromatic groups, and the bridging group and the hydroxy substituents of each C6 arylene group are arranged ortho, meta, or para (particularly para) relative to each other on the C6 arylene group. It may be derived from.

[0026]

[0035] In one embodiment, X a is a substituted or unsubstituted C 3~18 Cycloalkylidene, formula -C(R c )(R d )-(wherein, R c and R d are independently hydrogen, C 1~12 Alkyl, C 1~12 Cycloalkyl, C 7~12 Arylalcyl, C 7~12 Heteroalkyl, or cyclic C 7~12 C is heteroarylalkyl 1~25 Alkylidene, or a compound of the formula -C(=R e )-(wherein, R e is a divalent C 1~12 X may be a group of the formula (which is a hydrocarbon group). Exemplary groups of this type include methylene, cyclohexylmethylene, ethylidene, neopentylidene, and isopropylidene, as well as 2-[2.2.1]-bicycloheptylidene, cyclohexylidene, cyclopentylidene, cyclododecylidene, and adamantylidene. a A particular example where is a substituted cycloalkylidene is represented by the following formula (II):

[0027] [ka]

[0028] (In the formula, R a’ and R b’ are each independently C 1~12 Alkyl (e.g., C such as methyl) 1~4 alkyl), optionally positioned meta to the cyclohexylidene bridging group; R g is C 1~12 Alkyl (e.g., C 1~4 alkyl) or halogen; r and s are each independently 1 to 4 (e.g., 1); t is 0 to 10, e.g., 0 to 5) It is a cyclohexylidene-bridged alkyl-substituted bisphenol.

[0029]

[0036] The cyclohexylidene-bridged bisphenol may be the reaction product of two moles of o-cresol and one mole of cyclohexanone. In another embodiment, the cyclohexylidene-bridged bisphenol may be the reaction product of two moles of cresol and one mole of hydrogenated isophorone (e.g., 1,1,3-trimethyl-3-cyclohexan-5-one). Such cyclohexane-containing bisphenols, such as the reaction product of two moles of phenol and one mole of hydrogenated isophorone, are useful for making polycarbonate polymers with high glass transition temperatures and high heat distortion temperatures.

[0030]

[0037] In another embodiment, X a is C 1~18 Alkylene group, C 3~18 Cycloalkylene group, fused C 6~18 a cycloalkylene group, or a group of formula -B 1 -WB 2 -(In the formula, B 1 and B 2 independently C 1~6 is an alkylene group, and W is C 3~12 Cycloalkylidene group or C 6~16 It may also be a group of the formula (which is an arylene group).

[0031]

[0038] X a also has the following formula (III):

[0032] [ka]

[0033] (In the formula, R r , R p , R q and R t are each independently hydrogen, halogen, oxygen, or C 1~12 is an organic group, I is a direct bond, carbon, or divalent oxygen, sulfur, or -N(Z)-, where Z is hydrogen, halogen, hydroxy, C 1~12 Alkyl, C 1~12 Alkoxy or C 1~12 It is acyl, h is 0 to 2; j is 1 or 2, i is 0 or 1, k is 0 to 3, where R r , R p , R q and R t at least two of which together form a fused cyclic aliphatic, aromatic, or heteroaromatic ring Substitution of C 3~18 It may be a cycloalkylidene.

[0034]

[0039] Other useful aromatic dihydroxyaromatic compounds have the following formula (IV):

[0035] [ka]

[0036] (In the formula, R h are independently a halogen atom (e.g., bromine), C 1~10 Hydrocarbyl (e.g., C 1~10 alkyl group), halogen-substituted C 1~10 Alkyl group, C 6~10 Aryl group or halogen-substituted C 6~10 is an aryl group, n is 0 to 4) Includes those having the following.

[0037]

[0040] Specific examples of bisphenol compounds of formula (I) include, for example, 1,1-bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)propane (hereinafter "bisphenol A" or "BPA"), 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, 1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)n-butane, 2,2-bis(4-hydroxy-1-methylphenyl)propane, 1,1-bis(4-hydroxy-t-butylphenyl)propane, 3,3-bis(4-hydroxyphenyl)phthalimidine, 2-phenyl-3,3-bis(4-hydroxyphenyl)phthalimidine (PPPBP), and 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane (DMBPC). In one particular embodiment, the polycarbonate may be a linear homopolymer derived from bisphenol A, where in formula (I), A 1 and A 2 each of Y is p-phenylene; 1 is isopropylidene.

[0038]

[0041] Other examples of suitable aromatic dihydroxy compounds include, but are not limited to, 4,4'-dihydroxybiphenyl, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)diphenylmethane, bis(4-hydroxyphenyl)-1-naphthylmethane, 1,2-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane, bis( 4-hydroxyphenyl)phenylmethane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 1,1-bis(hydroxyphenyl)cyclopentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)isobutene, 1,1-bis(4-hydroxyphenyl)cyclododecane, trans-2,3-bis(4-hydroxyphenyl)-2-butene, 2,2-bis(4-hydroxyphenyl)adamantane, alpha,alpha'-bis(4-hydroxyphenyl)toluene, bis(4 -hydroxyphenyl)acetonitrile, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3-ethyl-4-hydroxyphenyl)propane, 2,2-bis(3-n-propyl-4-hydroxyphenyl)propane, 2,2-bis(3-isopropyl-4-hydroxyphenyl)propane, 2,2-bis(3-sec-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-t-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane, 2,2-bis(3-allyl-4-hydroxyphenyl)propane, 2,2-bis(3-methoxy-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene, 1,1-dibromo-2,2-bis(4-hydroxyphenyl)ethylene, 1,1-dichloro-2,2-bis(5-phenoxy-4-hydroxyphenyl)ethylene 4,4'-dihydroxybenzophenone, 3,3-bis(4-hydroxyphenyl)-2-butanone, 1,6-bis(4-hydroxyphenyl)-1,6-hexanedione, ethylene glycol bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfone, 9,9-bis(4-hydroxyphenyl)phlorine, 2,7-dihydroxypyrene, 6,6'-dihydroxy-3,3,3',3'-tetramethylspiro(bis)indane ("spirobiindane bisphenol"), 3,3-bis(4-hydroxyphenyl)phthalimide, 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene, 2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, and 2,7-dihydroxybenzofuran. Examples of suitable resorcinol compounds include hydroxycarbazole, resorcinol, 5-methylresorcinol, 5-ethylresorcinol, 5-propylresorcinol, 5-butylresorcinol, 5-t-butylresorcinol, 5-phenylresorcinol, 5-cumylresorcinol, 2,4,5,6-tetrafluororesorcinol, and substituted resorcinol compounds such as 2,4,5,6-tetrabromoresorcinol; catechol; hydroquinone; substituted hydroquinones such as 2-methylhydroquinone, 2-ethylhydroquinone, 2-propylhydroquinone, 2-butylhydroquinone, 2-t-butylhydroquinone, 2-phenylhydroquinone, 2-cumylhydroquinone, 2,3,5,6-tetramethylhydroquinone, 2,3,5,6-tetra-t-butylhydroquinone, 2,3,5,6-tetrafluorohydroquinone, and 2,3,5,6-tetrabromohydroquinone; and combinations thereof.

[0039]

[0042] The aromatic polycarbonates described above typically have a DTUL value, determined under a load of 1.8 MPa, of about 80°C to about 300°C, in some embodiments about 100°C to about 250°C, and in some embodiments about 140°C to about 220°C, as determined in accordance with ISO 75-2:2013. The glass transition temperature may also be, for example, about 50°C to about 250°C, in some embodiments about 90°C to about 220°C, and in some embodiments about 100°C to about 200°C, as determined in accordance with ISO 11357-2:2020. Such polycarbonates may also have an intrinsic viscosity, determined in accordance with ISO 1628-4:1998, of about 0.1 dl / g to about 6 dl / g, in some embodiments about 0.2 to about 5 dl / g, and in some embodiments about 0.3 to about 1 dl / g.

[0040]

[0043] In addition to the polymers mentioned above, highly crystalline aromatic polymers can also be utilized in the polymer composition. Particularly suitable examples of such polymers are liquid crystal polymers, which have a high degree of crystallinity that allows for efficient filling of small mold spaces. Liquid crystal polymers generally have a rod-like structure and are classified as "thermotropic" as long as they exhibit crystalline behavior in their molten state (e.g., a thermotropic nematic state). Such polymers typically have a DTUL value, determined according to ISO 75-2:2013 at a load of 1.8 MPa, of about 120°C to about 340°C, in some embodiments about 140°C to about 320°C, and in some embodiments about 150°C to about 300°C. The polymers also have relatively high melting temperatures, such as about 250°C to about 400°C, in some embodiments about 280°C to about 390°C, and in some embodiments about 300°C to about 380°C. Such polymers may be formed from one or more types of repeating units, as known in the art. Liquid crystal polymers, for example, generally have the following formula (I):

[0041] [ka]

[0042] (In the formula, Ring B is a substituted or unsubstituted 6-membered aryl group (e.g., 1,4-phenylene or 1,3-phenylene), a substituted or unsubstituted 6-membered aryl group fused to a substituted or unsubstituted 5- or 6-membered aryl group (e.g., 2,6-naphthalene), or a substituted or unsubstituted 6-membered aryl group linked to a substituted or unsubstituted 5- or 6-membered aryl group (e.g., 4,4-biphenylene); Y1 and Y2 are independently O, C(O), NH, C(O)HN, or NHC(O). The aromatic ester may contain one or more aromatic ester repeat units represented by:

[0043]

[0044] Typically, at least one of Y1 and Y2 is C(O). Examples of such aromatic ester repeat units include, for example, aromatic dicarboxylic acid repeat units (in Formula I, Y1 and Y2 are C(O)), aromatic hydroxycarboxylic acid repeat units (in Formula I, Y1 is O and Y2 is C(O)), and various combinations thereof.

[0044]

[0045] For example, aromatic hydroxycarboxylic acid repeat units derived from aromatic hydroxycarboxylic acids such as 4-hydroxybenzoic acid, 4-hydroxy-4'-biphenylcarboxylic acid, 2-hydroxy-6-naphthoic acid, 2-hydroxy-5-naphthoic acid, 3-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, 4'-hydroxyphenyl-4-benzoic acid, 3'-hydroxyphenyl-4-benzoic acid, 4'-hydroxyphenyl-3-benzoic acid, and the like, as well as alkyl, alkoxy, aryl, and halogen-substituted versions thereof, and combinations thereof, may be utilized. Particularly suitable aromatic hydroxycarboxylic acids are 4-hydroxybenzoic acid ("HBA") and 6-hydroxy-2-naphthoic acid (HNA). When utilized, repeat units derived from hydroxycarboxylic acids (e.g., HBA and / or HNA) typically comprise about 40 mol.% or more of the polymer, in some embodiments about 45 mol.% or more, and in some embodiments about 50 mol.% to 100 mol.%. In one embodiment, for example, the repeating units derived from HBA may comprise about 30 mol % to about 90 mol %, in some embodiments, about 40 mol % to about 85 mol %, and in some embodiments, about 50 mol % to about 80 mol % of the polymer. Similarly, the repeating units derived from HNA may comprise about 1 mol % to about 30 mol %, in some embodiments, about 2 mol % to about 25 mol %, and in some embodiments, about 3 mol % to about 15 mol % of the polymer.

[0045]

[0046] Also useful are aromatic dicarboxylic acid repeat units derived from aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyl ether-4,4'-dicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4,4'-dicarboxybiphenyl, bis(4-carboxyphenyl)ether, bis(4-carboxyphenyl)butane, bis(4-carboxyphenyl)ethane, bis(3-carboxyphenyl)ether, bis(3-carboxyphenyl)ethane, and the like, as well as alkyl-, alkoxy-, aryl-, and halogen-substituted versions thereof, and combinations thereof. Particularly suitable aromatic dicarboxylic acids include, for example, terephthalic acid ("TA"), isophthalic acid ("IA"), and 2,6-naphthalenedicarboxylic acid ("NDA"). When utilized, repeat units derived from aromatic dicarboxylic acids (e.g., IA, TA, and / or NDA) typically comprise from about 1 mol.% to about 50 mol.%, in some embodiments from about 2 mol.% to about 40 mol.%, and in some embodiments, from about 5 mol.% to about 30% of the polymer.

[0046]

[0047] Other repeat units can also be utilized in the polymer. For example, in certain embodiments, repeat units derived from aromatic diols such as hydroquinone, resorcinol, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl (or 4,4'-biphenol), 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, bis(4-hydroxyphenyl)ethane, and the like, as well as alkyl, alkoxy, aryl, and halogen-substituted versions thereof, and combinations thereof, may be utilized. Particularly suitable aromatic diols include, for example, hydroquinone ("HQ") and 4,4'-biphenol ("BP"). When utilized, repeat units derived from aromatic diols (e.g., HQ and / or BP) typically comprise from about 1 mol.% to about 30 mol.%, in some embodiments, from about 2 mol.% to about 25 mol.%, and in some embodiments, from about 5 mol.% to about 20% of the polymer. Repeat units such as those derived from aromatic amides (e.g., acetaminophen (“APAP”)) and / or aromatic amines (e.g., 4-aminophenol (“AP”), 3-aminophenol, 1,4-phenylenediamine, 1,3-phenylenediamine, etc.) may also be utilized. When utilized, repeat units derived from aromatic amides (e.g., APAP) and / or aromatic amines (e.g., AP) typically comprise from about 0.1 mol.% to about 20 mol.%, in some embodiments from about 0.5 mol.% to about 15 mol.%, and in some embodiments, from about 1 mol.% to about 10% of the polymer. It should also be understood that various other monomeric repeat units may be incorporated into the polymer. For example, in certain embodiments, the polymer may contain one or more repeat units derived from non-aromatic monomers, such as aliphatic or alicyclic hydroxycarboxylic acids, dicarboxylic acids, diols, amides, amines, and the like. Of course, in other embodiments, the polymer may be “fully aromatic” in that it does not include repeat units derived from non-aromatic (e.g., aliphatic or alicyclic) monomers.

[0047]

[0048] Although not required, the liquid crystal polymer may be a "low naphthene" polymer so long as it contains a relatively high content of repeat units derived from naphthenic hydroxycarboxylic acids and naphthenic dicarboxylic acids, such as naphthalene-2,6-dicarboxylic acid ("NDA"), 6-hydroxy-2-naphthoic acid ("HNA"), or combinations thereof. That is, the total amount of repeat units derived from naphthenic hydroxycarboxylic acids and / or dicarboxylic acids (e.g., NDA, HNA, or combinations of HNA and NDA) is typically about 15 mol.% or less, in some embodiments about 10 mol.% or less, and in some embodiments, from about 1 mol.% to about 8 mol.% of the polymer. In one particular embodiment, for example, repeat units derived from naphthalene-2,6-dicarboxylic acid ("HNA") may be present in an amount of only about 0.5 mol.% to about 15 mol.%, in some embodiments about 1 mol.% to about 10 mol.%, and in some embodiments, from about 2 mol.% to about 8 mol.% of the polymer. In such embodiments, the liquid crystal polymer may also contain various other monomers, such as an aromatic hydroxycarboxylic acid (e.g., HBA) in an amount of from about 30 mol.% to about 70 mol.%, and in some embodiments, from about 40 mol.% to about 65 mol.%; an aromatic dicarboxylic acid (e.g., IA and / or TA) in an amount of from about 2 mol.% to about 30 mol.%, and in some embodiments, from about 5 mol.% to about 25 mol.%; and / or an aromatic diol (e.g., BP and / or HQ) in an amount of from about 2 mol.% to about 40 mol.%, and in some embodiments, from about 5 mol.% to about 35 mol.%.

[0048]

[0049] Of course, in other embodiments, the liquid crystal polymer may be a "high naphthene" polymer, so long as it contains a relatively high content of repeat units derived from naphthenic hydroxycarboxylic acids and naphthenic dicarboxylic acids, such as naphthalene-2,6-dicarboxylic acid ("NDA"), 6-hydroxy-2-naphthoic acid ("HNA"), or combinations thereof. That is, the total amount of repeat units derived from naphthenic hydroxycarboxylic acids and / or dicarboxylic acids (e.g., NDA, HNA, or a combination of HNA and NDA) is typically greater than about 15 mol.%, in some embodiments about 18 mol.% or greater, and in some embodiments, from about 20 mol.% to about 60 mol.% of the polymer. In one particular embodiment, for example, repeat units derived from naphthalene-2,6-dicarboxylic acid ("NDA") may comprise from about 10 mol.% to about 40 mol.%, in some embodiments from about 12 mol.% to about 35 mol.%, and in some embodiments, from about 15 mol.% to about 30 mol.% of the polymer. In such embodiments, the liquid crystal polymer may also contain various other monomers, such as an aromatic hydroxycarboxylic acid (e.g., HBA) in an amount of about 20 mol.% to about 60 mol.%, and in some embodiments, about 30 mol.% to about 50 mol.%; an aromatic dicarboxylic acid (e.g., IA and / or TA) in an amount of about 2 mol.% to about 30 mol.%, and in some embodiments, about 5 mol.% to about 25 mol.%; and / or an aromatic diol (e.g., BP and / or HQ) in an amount of about 2 mol.% to about 40 mol.%, and in some embodiments, about 5 mol.% to about 35 mol.%.

[0049]

[0050] In certain embodiments, all of the liquid crystalline polymers are "low naphthene" polymers as described above. In other embodiments, all of the liquid crystalline polymers are "high naphthene" polymers as described above. In some cases, blends of such polymers may be used. For example, the low naphthene liquid crystalline polymer may comprise from about 1 wt.% to about 50 wt.%, in some embodiments from about 2 wt.% to about 40 wt.%, and in some embodiments from about 5 wt.% to about 30 wt.% of the total amount of liquid crystalline polymer in the composition, and the high naphthene liquid crystalline polymer may comprise from about 50 wt.% to about 99 wt.%, in some embodiments from about 60 wt.% to about 98 wt.%, and in some embodiments from about 70 wt.% to about 95 wt.% of the total amount of liquid crystalline polymer in the composition.

[0050] B. Conductive filler

[0051] As noted above, conductive fillers are also utilized in polymer compositions to assist in achieving desired surface and / or volume resistivity values ​​for the polymer composition. This may be achieved by selecting a single material for the filler that has the desired resistivity, or by blending multiple materials together (e.g., insulating and conductive) so that the resulting filler has the desired resistivity. In one particular embodiment, the resistivity is less than about 1 ohm-cm, in some embodiments less than about 0.1 ohm-cm, and in some embodiments less than about 1×10 ohm-cm, as determined at a temperature of about 20° C., for example, according to ASTM D257-14 (technically equivalent to IEC 62631-3-1). -8 ohm·cm ~ approx. 1×10 -2Conductive materials having a volume resistivity of ohm·cm may be utilized. Suitable conductive carbon materials include, for example, graphite, carbon black, carbon fiber, graphene, and carbon nanotubes. Other suitable conductive fillers include metals (e.g., metal particles, metal flakes, metal fibers, etc.), ionic liquids, and the like. Regardless of the material utilized, the conductive filler typically comprises from about 0.5 to about 20 parts by weight, in some embodiments from about 1 to about 15 parts by weight, and in some embodiments, from about 2 to about 8 parts by weight, per 100 parts by weight of the polymer matrix. For example, the conductive filler may comprise from about 0.1 wt.% to about 10 wt.%, in some embodiments, from about 0.2 wt.% to about 8 wt.%, and in some embodiments, from about 0.5 wt.% to about 4 wt.% of the polymer composition.

[0051] C. Mineral fillers

[0052] If desired, the polymer composition may contain one or more mineral fillers distributed throughout the polymer matrix. Such mineral fillers typically comprise from about 10 to about 80 parts, in some embodiments from about 20 to about 70 parts, and in some embodiments, from about 30 to about 60 parts per 100 parts by weight of the polymer matrix. The mineral filler may comprise, for example, from about 5 wt.% to about 60 wt.%, in some embodiments from about 10 wt.% to about 55 wt.%, and in some embodiments, from about 25 wt.% to about 40 wt.% of the polymer composition. Furthermore, the weight ratio of mineral filler to conductive filler may range from about 2 to about 500, in some embodiments from about 3 to about 150, in some embodiments from about 4 to about 75, and in some embodiments, from about 5 to about 15. By selectively adjusting the type and relative amount of mineral filler, the inventors have discovered that not only can the mechanical properties be improved, but also the thermal conductivity can be increased without significantly affecting the overall electrical conductivity of the polymer composition. This allows the composition to create a thermal path for heat transfer away from the resulting electronic device, enabling rapid elimination of "hot spots" and reduced overall temperature during use. The composition may, for example, exhibit an in-plane thermal conductivity of about 0.2 W / m·K or greater, in some embodiments about 0.5 W / m·K or greater, in some embodiments about 0.6 W / m·K or greater, in some embodiments about 0.8 W / m·K or greater, and in some embodiments, from about 1 to about 3.5 W / m·K, as determined in accordance with ASTM E 1461-13. The composition may also exhibit an in-plane thermal conductivity of about 0.3 W / m·K or greater, in some embodiments about 0.5 W / m·K or greater, in some embodiments about 0.40 W / m·K or greater, and in some embodiments, from about 0.7 to about 2 W / m·K, as determined in accordance with ASTM E 1461-13. Remarkably, it has been discovered that such thermal conductivities can be achieved without the use of conventional materials with high intrinsic thermal conductivities. For example, the polymer composition may be free of fillers that generally have an intrinsic thermal conductivity of 50 W / m·K or greater, in some embodiments 100 W / m·K or greater, and in some embodiments 150 W / m·K or greater.Examples of such high intrinsic thermal conductivity materials include, for example, boron nitride, aluminum nitride, magnesium silicon nitride, graphite (e.g., expanded graphite), silicon carbide, carbon nanotubes, zinc oxide, magnesium oxide, beryllium oxide, zirconium oxide, yttrium oxide, aluminum powder, and copper powder. While it is typically desirable to minimize the presence of such high intrinsic thermal conductivity materials, they may nevertheless be present in relatively low percentages, such as about 10 wt.% or less, in some embodiments about 5 wt.% or less, and in some embodiments, about 0.01 wt.% to about 2 wt.% of the polymer composition in certain embodiments.

[0052]

[0053] The nature of the mineral filler utilized in the polymer composition may vary, including mineral particles, mineral fibers (or "whiskers"), and blends thereof. Suitable mineral fibers include, for example, silicates, such as neosilicates, sorosilicates, inosilicates (e.g., calcium inosilicates such as wollastonite; calcium magnesium inosilicates such as tremolite; calcium magnesium iron inosilicates such as actinolite; magnesium iron inosilicates such as anthophilite), phyllosilicates (e.g., aluminum phyllosilicates such as palygorskite), tectosilicates, and the like; sulfates such as calcium sulfate (e.g., dehydrated or anhydrous gypsum); and mineral wool (e.g., rock or slag wool). Inosilicates, such as wollastonite fiber available from Nyco Minerals under the trade name NYGLOS® (e.g., NYGLOS® 4W or NYGLOS® 8), are particularly suitable. The mineral fibers may have a median diameter of about 1 to about 35 micrometers, in some embodiments, about 2 to about 20 micrometers, in some embodiments, about 3 to about 15 micrometers, and in some embodiments, about 7 to about 12 micrometers. The mineral fibers may also have a narrow size distribution. That is, at least about 60% by volume of the fibers, in some embodiments, at least about 70% by volume of the fibers, and in some embodiments, at least about 80% by volume of the fibers may have a size within the above range. While not intending to be limited by theory, it is believed that mineral fibers having the above size characteristics may move more easily through molding equipment, thereby improving their distribution within the polymer matrix and minimizing the creation of surface defects. In addition to having the above size characteristics, the mineral fibers may also have a relatively high aspect ratio (average length divided by median diameter), which helps further improve the mechanical properties and surface quality of the resulting polymer composition. For example, the mineral fibers may have an aspect ratio of about 2 to about 100, in some embodiments, about 2 to about 50, in some embodiments, about 3 to about 20, and in some embodiments, about 4 to about 15.The volume average length of such mineral fibers may range, for example, from about 1 to about 200 micrometers, in some embodiments from about 2 to about 150 micrometers, in some embodiments from about 5 to about 100 micrometers, and in some embodiments, from about 10 to about 50 micrometers.

[0053]

[0054] Other suitable mineral fibers are mineral particles. The average diameter of the particles may range, for example, from about 5 micrometers to about 200 micrometers, in some embodiments from about 8 micrometers to about 150 micrometers, and in some embodiments, from about 10 micrometers to about 100 micrometers. The shape of the particles may vary as desired, for example, granular, flake-shaped, and the like. Flake-shaped particles may be utilized having a relatively high aspect ratio (e.g., average diameter divided by average thickness), for example, about 4 or greater, in some embodiments, about 8 or greater, and in some embodiments, from about 10 to about 500. Similarly, the average thickness of such flake-shaped particles may be about 2 micrometers or less, in some embodiments, from about 5 nanometers to about 1 micrometer, and in some embodiments, from about 20 nanometers to about 500 nanometers. Regardless of their shape and size, the particles are typically formed from natural and / or synthetic silicate minerals, such as talc, mica, halloysite, kaolinite, illite, montmorillonite, vermiculite, palygorskite, pyrophyllite, calcium silicate, aluminum silicate, wollastonite, and the like. Talc and mica are particularly preferred. For example, muscovite (KAl2(AlSi3)O 10 (OH)2), biotite (K(Mg,Fe)3(AlSi3)O 10 (OH)2), phlogopite (KMg3(AlSi3)O 10 (OH)2), red mica (K(Li,Al) 2-3 (AlSi3)O 10 (OH)2), glauconite (K,Na)(Al,Mg,Fe)2(Si,Al)4O 10 Mica in any form, including but not limited to (OH)2), may generally be utilized. Muscovite-based mica is particularly suitable for use in polymer compositions.

[0054] D. Optional Additives

[0055] A wide variety of additional additives may be included in the polymer composition, such as glass fibers, impact modifiers, lubricants, pigments (e.g., carbon black), antioxidants, stabilizers, surfactants, waxes, flame retardants, anti-sag additives, nucleating agents (e.g., boron nitride), and other materials added to improve properties and processability. For example, lubricants may be utilized in the polymer composition in amounts of about 0.05 wt.% to about 1.5 wt.%, and in some embodiments, about 0.1 wt.% to about 0.5 wt.% (by weight) of the polymer composition. Examples of such lubricants include fatty acid esters, their salts, esters, fatty acid amides, organophosphate esters, and hydrocarbon waxes of the type commonly used as lubricants in the processing of engineering plastic materials, including mixtures thereof. Suitable fatty acids typically have a backbone carbon chain of about 12 to about 60 carbon atoms, such as myristic acid, palmitic acid, stearic acid, arachidic acid, montanic acid, octadecynic acid, and paric acid. Suitable esters include fatty acid esters, fatty alcohol esters, wax esters, glycerol esters, glycol esters, and complex esters. Fatty acid amides include fatty primary amides, fatty secondary amides, methylene and ethylene bisamides, and alkanolamides such as palmitic acid amide, stearic acid amide, oleic acid amide, and N,N'-ethylenebisstearamide. Also suitable are metal salts of fatty acids such as calcium stearate, zinc stearate, and magnesium stearate; hydrocarbon waxes including paraffin wax, polyolefin and oxidized polyolefin wax, and microcrystalline wax. Particularly suitable lubricants are stearic acid, salts, or amides such as pentaerythritol tetrastearate, calcium stearate, or N,N'-ethylenebisstearamide. Yet another suitable lubricant may be a siloxane polymer, which helps improve internal lubrication and enhance the wear and friction properties of the composition when it encounters another surface. Such siloxane polymers typically comprise from about 0.2 to about 20 parts, in some embodiments from about 0.5 to about 10 parts, and in some embodiments from about 0.8 to about 5 parts per 100 parts of the polymer matrix utilized in the composition.Any of a variety of siloxane polymers may generally be utilized. Siloxane polymers include, for example, those having the formula: R r SiO (4-r / 2) (In the formula, R is independently hydrogen or a substituted or unsubstituted hydrocarbon group; r is 0, 1, 2, or 3) The term "siloxane" may include any polymer, copolymer or oligomer containing siloxane units in a backbone having the formula:

[0055]

[0056] Some examples of suitable groups R include, for example, optionally substituted alkyl, aryl, alkylaryl, alkenyl or alkynyl, or cycloalkyl groups, which may be interrupted by heteroatoms, i.e., may contain heteroatoms in the carbon chain or ring. Suitable alkyl groups include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, and tert-pentyl groups, hexyl groups (e.g., n-hexyl), heptyl groups (e.g., n-heptyl), octyl groups (e.g., n-octyl), isooctyl groups (e.g., 2,2,4-trimethylpentyl), nonyl groups (e.g., n-nonyl), decyl groups (e.g., n-decyl), dodecyl groups (e.g., n-dodecyl), and octadecyl groups (e.g., n-octadecyl). Similarly, suitable cycloalkyl groups include cyclopentyl, cyclohexyl, cycloheptyl, methylcyclohexyl, etc., suitable aryl groups include phenyl, biphenyl, naphthyl, anthryl, and phenanthryl, suitable alkylaryl groups include o-, m-, or p-tolyl, xylyl, ethylphenyl, etc., and suitable alkenyl or alkynyl groups include vinyl, 1-propenyl, 1-butenyl, 1-pentenyl, 5-hexenyl, butadienyl, hexadienyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, ethynyl, propargyl, 1-propynyl, etc. Examples of substituted hydrocarbon groups are halogenated alkyl groups (e.g., 3-chloropropyl, 3,3,3-trifluoropropyl, and perfluorohexylethyl) and halogenated aryl groups (e.g., p-chlorophenyl and p-chlorobenzyl). In one particular embodiment, the siloxane polymer comprises alkyl groups (e.g., methyl groups) attached to at least 70 mol % of the Si atoms, and optionally vinyl and / or phenyl groups attached to 0.001 to 30 mol % of the Si atoms. The siloxane polymer is also preferably composed primarily of diorganosiloxane units.The terminal groups of the polyorganosiloxane may be trialkylsiloxy groups, particularly trimethylsiloxy groups, or dimethylvinylsiloxy groups. However, one or more of these alkyl groups may be substituted with hydroxy groups or alkoxy groups such as methoxy or ethoxy groups. Particularly suitable examples of siloxane polymers include, for example, dimethylpolysiloxane, phenylmethylpolysiloxane, vinylmethylpolysiloxane, and trifluoropropylpolysiloxane.

[0056]

[0057] The siloxane polymer may also contain reactive functional groups such as one or more of vinyl groups, hydroxyl groups, hydride, isocyanate groups, epoxy groups, acid groups, halogen atoms, alkoxy groups (e.g., methoxy, ethoxy, and propoxy), acyloxy groups (e.g., acetoxy and octanoyloxy), ketoximate groups (e.g., dimethylketoxime, methylketoxime, and methylethylketoxime), amino groups (e.g., dimethylamino, diethylamino, and butylamino), amide groups (e.g., N-methylacetamide and N-ethylacetamide), acid amide groups, amino-oxy groups, mercapto groups, alkenyloxy groups (e.g., vinyloxy, isopropenyloxy, and 1-ethyl-2-methylvinyloxy), alkoxyalkoxy groups (e.g., methoxyethoxy, ethoxyethoxy, and methoxypropoxy), aminoxy groups (e.g., dimethylaminooxy and diethylaminooxy), mercapto groups, and the like, on at least some of the siloxane monomer units of the polymer.

[0057]

[0058] Regardless of their specific structure, siloxane polymers typically have relatively high molecular weights, reducing their likelihood of migration or diffusion to the surface of the polymer composition, thereby further minimizing the possibility of phase separation. For example, siloxane polymers typically have a weight average molecular weight of about 100,000 grams per mole or greater, in some embodiments about 200,000 grams per mole or greater, and in some embodiments, from about 500,000 grams per mole to about 2,000,000 grams per mole. Siloxane polymers may also have relatively high kinematic viscosities, such as about 10,000 centistokes or greater, in some embodiments about 30,000 centistokes or greater, and in some embodiments, from about 50,000 to about 500,000 centistokes.

[0058]

[0059] If desired, silica particles (e.g., fumed silica) can also be utilized in combination with the siloxane polymer to help improve its ability to disperse in the composition. Such silica particles can range, for example, from about 5 nanometers to about 50 nanometers in particle size, and have a density of about 50 square meters per gram (m 2 / g) ~ approx. 600m 2 / g of surface area, and / or approximately 160 kilograms per cubic meter (kg / m 3 ) ~ approx. 190kg / m 3 The silica particles may have a density of about 100 to about 100 parts by weight, and in some embodiments, about 20 to about 60 parts by weight, per 100 parts by weight of the siloxane polymer. In one embodiment, the silica particles can be combined with the siloxane polymer and then added to the polymer composition. For example, a mixture comprising ultra-high molecular weight polydimethylsiloxane and fumed silica can be incorporated into the polymer composition. Such a preformed mixture is available as Genioplast® Pellet S from Wacker Chemie, AG.

[0059]

[0060] The components used to form the polymer composition may be combined together using any of a variety of different techniques, as known in the art. In one particular embodiment, for example, a thermoplastic high-performance polymer, a conductive filler, and other optional additives are melt-processed as a mixture in an extruder to form the polymer composition. The mixture can be melt-mixed in a single-screw or multi-screw extruder, for example, at temperatures of about 250°C to about 450°C. In one embodiment, the mixture can be melt-processed in an extruder containing multiple temperature zones. The temperature of each zone is typically set within a range of about -60°C to about 25°C relative to the melt temperature of the polymer. By way of example, the mixture can be melt-processed using a twin-screw extruder, such as a Leistritz 18mm co-rotating, fully intermeshing twin-screw extruder. A versatile screw design can be used to melt-process the mixture. In one embodiment, a mixture containing all of the components can be fed into the feed throat of the first barrel by a metering feeder. In another embodiment, different components can be added at different addition points in the extruder, as is known. For example, the polymer can be applied to a feed port, with specific additives (e.g., conductive fillers) added downstream in the same or different temperature zones. In either case, the resulting mixture can be melted and mixed and then extruded through a die. The extruded polymer composition can then be quenched in a water bath to solidify it, pelletized in a pelletizer, and subsequently dried.

[0060]

[0061] The melt viscosity of the resulting composition is generally sufficiently low so that the composition can easily flow into the cavity of a mold for forming a miniature circuit board. For example, in one particular embodiment, the polymer composition has a melt viscosity of 1000 s -1 The composition may have a melt viscosity of from about 10 to about 250 Pa·s, in some embodiments from about 15 to about 200 Pa·s, in some embodiments from about 20 to about 150 Pa·s, and in some embodiments from about 30 to about 100 Pa·s, determined at a shear rate of from about 10 to about 250 Pa·s, in some embodiments from about 15 to about 200 Pa·s, in some embodiments from about 20 to about 150 Pa·s, and in some embodiments from about 30 to about 100 Pa·s. The melt viscosity may be determined according to ISO Test No. 11443:2014 at a temperature 15°C above the melt temperature of the composition (e.g., about 340°C for a melt temperature of about 325°C).

[0061] II. Substrate

[0062] Substrates may be formed from the polymer composition using a variety of different techniques. Suitable techniques include, for example, injection molding, low-pressure injection molding, extrusion compression molding, gas injection molding, foam injection molding, low-pressure gas injection molding, low-pressure foam injection molding, gas extrusion compression molding, foam extrusion compression molding, extrusion molding, foam extrusion molding, compression molding, foam compression molding, and gas compression molding. For example, an injection molding system may be utilized, including a mold into which the polymer composition can be injected. The time in the injector can be controlled and optimized to prevent pre-solidification of the polymer matrix. Once the cycle time is reached and the barrel is full for discharge, a piston may be used to inject the composition into the mold cavity. Compression molding systems may also be utilized. Similar to injection molding, the polymer composition can also be formed into the desired article within a mold. The composition may be placed into the compression mold using any known technique, such as by being picked up by an automated robotic arm. The temperature of the mold may be maintained at or above the solidification temperature of the polymer composition for a desired period of time to allow solidification. The molded article may then be solidified by lowering the temperature below the melting point. The resulting article may then be demolded. The cycle time of each molding process can be tailored to the polymer composition to achieve sufficient bonding and improve overall process productivity. Due in part to the beneficial properties of the polymer composition, the resulting substrate may have a very small size, such as a thickness of about 5 millimeters or less, in some embodiments about 4 millimeters or less, and in some embodiments, about 0.5 to about 3 millimeters. Typically, molded parts are molded using a one-component injection molding process.

[0062] III. Conductive Elements

[0063] One or more conductive elements may be deposited on the substrate using any of a variety of known metal deposition techniques, such as plating (e.g., electrolytic plating, electroless plating, etc.), printing (e.g., digital printing, aerosol jet printing, etc.). The conductive elements may contain one or more of a variety of conductive materials, such as metals, e.g., gold, silver, nickel, aluminum, copper, and mixtures or alloys thereof. In one embodiment, for example, the conductive elements may include copper and / or nickel (e.g., pure or alloys thereof). If desired, a seed layer may first be formed on the substrate to facilitate the metal deposition process.

[0063]

[0064] When plating is utilized as the deposition technique, the process may vary as desired. In certain embodiments, for example, the process may include first forming a pattern on the surface of the substrate based on the desired circuit interconnect pattern. This may be accomplished using various known techniques, such as laser ablation or patterning, plasma etching, ultraviolet treatment, acid etching, and the like. In either case, after forming the desired pattern on the substrate, the patterned area may optionally be subjected to an activation process to prepare it for subsequent metal deposition. During this process, the patterned substrate may be contacted with an activation solution containing a metal such as palladium, platinum, iridium, rhodium, and mixtures thereof. Palladium is particularly preferred. After the surface has been prepared as described above, a first metal layer may be formed thereon by, for example, a process known as electroless plating. Electroless plating may occur by an autocatalytic reaction in which the metal deposited on the surface acts as a catalyst for further deposition. Typically, nickel and / or copper are electrolessly plated onto the surface of the patterned substrate. Electroless nickel plating can be achieved, for example, using a solution containing a nickel salt (e.g., nickel sulfate). If desired, the patterned substrate may be subjected to one or more additional steps to form a final metal coating layer. Additional coating layers are typically deposited using a process known as electroplating, during which the patterned substrate is contacted with a metal solution and subjected to an electric current to initiate metal deposition. For example, a second metal layer may be electrolytically deposited on a first metal layer (e.g., electrolessly plated copper and / or nickel). The second metal layer may comprise, for example, copper or nickel. In certain embodiments, one or more additional metal layers, such as copper and / or nickel, may also be electrolytically deposited on the second metal layer.

[0064] IV.Electronic components

[0065] The circuit structures of the present invention may be utilized in a wide variety of electronic components, such as printed circuit boards, flex circuits, connectors, thermal management features, EMI shielding, high current conductors, RFID devices, antennas, wireless power devices, sensors, MEMS devices, LED devices, microprocessors, memory devices, ASICs, passive devices, impedance controlled devices, electromechanical devices, sensors, or combinations thereof. In one embodiment, for example, the conductive element may be an antenna element (e.g., an antenna resonating element), such that the resulting component forms an antenna system. The conductive elements may form a variety of different types of antennas, such as patch antenna elements, inverted-F antenna elements, closed and open slot antenna elements, loop antenna elements, monopoles, dipoles, planar inverted-F antenna elements, hybrids of these designs, and the like. The resulting antenna system may be utilized in a variety of different electronic components. By way of example, the antenna system may be formed in electronic components such as desktop computers, portable computers, handheld electronic devices, automotive equipment, and the like. In one preferred configuration, the antenna system is formed within the housing of a relatively compact portable electronic component, which has a relatively small amount of available interior space. Examples of suitable portable electronic components include mobile phones, laptop computers, small portable computers (e.g., ultraportable computers, netbook computers, and tablet computers), watch devices, pendant devices, headphone and earphone devices, media players with wireless communication capabilities, handheld computers (sometimes also called personal digital assistants), remote controllers, global positioning system (GPS) devices, handheld gaming devices, etc. Antennas can also be integrated into other components, such as the camera module, speaker, or battery cover of a handheld device.

[0065]

[0066] One particularly suitable electronic component, shown in FIGS. 1-2, is a handheld device 10 with mobile phone functionality. As shown in FIG. 1, device 10 may have a housing 12 formed from plastic, metal, other suitable dielectric material, other suitable conductive material, or a combination of such materials. A display 14, such as a touchscreen display, may be provided on the front side of device 10. Device 10 may also have a speaker port 40 and other input / output ports. One or more buttons 38 and other user input devices may be used to collect user input. As shown in FIG. 2, an antenna system 26 is also provided on the back side 42 of device 10, although it should be understood that the antenna system may generally be located in any desired location on the device. The antenna system may be electrically connected to other components within the electronic device using any of a variety of known techniques. Referring again to FIGS. 1-2, for example, housing 12 or a portion of housing 12 may serve as a conductive ground plane for antenna system 26. This is illustrated in more detail in Figure 3, which shows antenna system 26 fed by radio frequency source 52 at positive antenna feed terminal 54 and ground antenna feed terminal 56. Positive antenna feed terminal 54 may be coupled to antenna resonating element 58, and ground antenna feed terminal 56 may be coupled to ground element 60. Resonating element 58 may have main arm 46 and shorting branch 48 connecting main arm 46 to ground 60.

[0066]

[0067] Various other configurations for electrically connecting the antenna system are also contemplated. For example, in FIG. 4 , the antenna system is based on a monopole antenna configuration, with the resonating element 58 having a curved, serpentine path shape. In such an embodiment, the feed terminal 54 may be connected to one end of the resonating element 58, and the ground feed terminal 56 may be coupled to the housing 12 or other suitable ground plane element. In another embodiment shown in FIG. 5 , a conductive antenna element 62 is configured to define a closed slot 64 and an open slot 66. The antenna formed from the structure 62 may be fed using the positive antenna feed terminal 54 and the ground antenna feed terminal 56. In this type of arrangement, the slots 64 and 66 function as antenna resonating elements for the antenna element 26. The size of the slots 64 and 66 may be configured so that the antenna element 26 operates in a desired communications band (e.g., 2.4 GHz, 5 GHz, etc.). Another possible configuration of the antenna element 26 is shown in FIG. 6 . In this embodiment, antenna element 26 has a patch antenna resonating element 68 and may be fed using positive antenna feed terminal 54 and ground antenna feed terminal 56. Ground 60 may be associated with housing 12 or other suitable ground plane element of device 10. FIG. 7 illustrates yet another exemplary configuration that may be used for the antenna elements of antenna system 26. As shown, antenna resonating element 58 has two main arms 46A and 46B. Arm 46A is shorter than arm 46B and is therefore associated with a higher operating frequency than arm 46A. By using two or more separate resonating element structures of different sizes, antenna resonating element 58 can be configured to cover a wider bandwidth or more than one communications band of interest.

[0067]

[0068] In certain embodiments of the present invention, the circuit structures may be particularly well suited for use in high-frequency antennas and antenna arrays for use in base stations, repeaters (e.g., "femtocells"), relay stations, terminals, user devices, and / or other suitable components of 5G systems. As used herein, "5G" generally refers to high-speed data communication via radio frequency signals. 5G networks and systems are capable of communicating data at speeds significantly faster than previous generations of data communication standards (e.g., "4G," "LTE"). For example, as used herein, "5G frequencies" may refer to frequencies above 1.5 GHz, in some embodiments above about 2.0 GHz, in some embodiments above about 2.5 GHz, in some embodiments above about 3.0 GHz, in some embodiments between about 3 GHz and about 300 GHz or above, in some embodiments between about 4 GHz and about 80 GHz, in some embodiments between about 5 GHz and about 80 GHz, in some embodiments between about 20 GHz and about 80 GHz, and in some embodiments between about 28 GHz and about 60 GHz. Various standards and specifications have been published that quantify the requirements for 5G communications. As an example, the International Telecommunications Union (ITU) published the International Mobile Telecommunications-2020 ("IMT-2020") standard in 2015. The IMT-2020 standard specifies various data transmission criteria for 5G (e.g., downlink and uplink data rates, latency, etc.). The IMT-2020 standard defines uplink and downlink peak data rates as the minimum data rates for uploading and downloading data that a 5G system must support. The IMT-2020 standard sets the downlink peak data rate requirement at 20 Gbit / s and the uplink peak data rate at 10 Gbit / s. As another example, 3 rdThe Third Generation Partnership Project (3GPP®) has recently published a new standard for 5G called "5GNR." In 2018, 3GPP® published "Release 15," which defines "Phase 1" for the standardization of 5GNR. 3GPP® defines the 5G frequency bands as "Frequency Range 1" (FR1), which generally includes frequencies below 6 GHz, and "Frequency Range 2" (FR2), which is the frequency band in the range of 20-60 GHz. The antenna systems described herein may meet or qualify for "5G" under standards published by 3GPP®, such as Release 15 (2018), and / or the IMT-2020 standard.

[0068]

[0069] To achieve high-speed data communications at high frequencies, antenna elements and arrays can utilize small feature sizes / spacings (e.g., fine-pitch technology), which can improve antenna performance. For example, the feature size (spacing between antenna elements, width of antenna elements), etc., generally depends on the wavelength (λ) of the desired transmit and / or receive radio frequency propagating through the substrate dielectric on which the antenna elements are formed (e.g., nλ / 4, where n is an integer). Furthermore, beamforming and / or beamsteering may be utilized to facilitate reception and transmission across multiple frequency ranges or channels (e.g., multiple-input multiple-output (MIMO), massive MIMO).

[0069]

[0070] High-frequency 5G antenna elements can have various configurations. For example, 5G antenna elements may be or include coplanar waveguide elements, patch arrays (e.g., mesh grid patch arrays), other suitable 5G antenna configurations. Antenna elements may be configured to provide MIMO, massive MIMO functionality, beam steering, etc. As used herein, "massive" MIMO functionality generally refers to providing a large number of transmit and receive channels in an antenna array, for example, 8 transmit (Tx) and 8 receive (Rx) channels (abbreviated as 8x8). Massive MIMO functionality may be provided in 8x8, 12x12, 16x16, 32x32, 64x64, or greater.

[0070]

[0071] The antenna elements can have a variety of configurations and arrangements and can be fabricated using a variety of manufacturing techniques. As an example, the antenna elements and / or associated elements (e.g., ground elements, feed lines, etc.) can utilize fine-pitch technology. Fine-pitch technology generally refers to small or fine spacing between their components or leads. For example, the feature size and / or spacing between antenna elements (or between antenna elements and ground planes) can be about 1,500 micrometers or less, in some embodiments 1,250 micrometers or less, in some embodiments 750 micrometers or less (e.g., center-to-center spacing of 1.5 mm or less), 650 micrometers or less, in some embodiments 550 micrometers or less, in some embodiments 450 micrometers or less, in some embodiments 350 micrometers or less, in some embodiments 250 micrometers or less, in some embodiments 150 micrometers or less, in some embodiments 100 micrometers or less, and in some embodiments 50 micrometers or less. However, it should be understood that smaller and / or larger feature sizes and / or spacings can be utilized within the scope of the present disclosure.

[0071]

[0072] As a result of such small feature sizes, antenna systems can be implemented with a large number of antenna elements in a small footprint. For example, antenna arrays may have an average antenna element density of more than 1,000 antenna elements per square centimeter, in some embodiments more than 2,000 antenna elements per square centimeter, in some embodiments more than 3,000 antenna elements per square centimeter, in some embodiments more than 4,000 antenna elements per square centimeter, in some embodiments more than 6,000 antenna elements per square centimeter, and in some embodiments more than about 8,000 antenna elements per square centimeter. Such a dense arrangement of antenna elements can increase the number of channels of MIMO functionality per unit area of ​​antenna area. For example, the number of channels may correspond to (e.g., be equal to or proportional to) the number of antenna elements.

[0072]

[0073] 8, one embodiment of a 5G antenna system 100 is shown that includes a base station 102, one or more relay stations 104, one or more user computing devices 106, one or more Wi-Fi repeaters 108 (e.g., “femtocells”), and / or other suitable antenna components of the 5G antenna system 100. The relay stations 104 may be configured to relay or “repeat” signals between the base station 102 and the user computing devices 106 and / or relay stations 104 to facilitate communication with the base station 102 by the user computing devices 106 and / or other relay stations 104. The base station 102 may include a MIMO antenna array 110 configured to receive and / or transmit radio frequency signals 112 to and / or from the relay stations 104, the Wi-Fi repeaters 108, and / or directly to the user computing devices 106. The user computing devices 106 are not necessarily limited by the present invention and include devices such as 5G smartphones.

[0073]

[0074] The MIMO antenna array 110 may utilize beam steering to focus or direct radio frequency signals 112 toward the relay station 104. For example, the MIMO antenna array 110 may be configured to adjust an elevation angle 114 relative to the XY plane and / or a heading angle 116 relative to the Z direction, defined in the ZY plane. Similarly, one or more of the relay station 104, user computing device 106, and Wi-Fi repeater 108 may utilize beam steering to improve reception and / or transmission capabilities for the MIMO antenna array 110 by directing the sensitivity and / or power transmission of the devices 104, 106, and 108 toward the MIMO antenna array 110 of the base station 102 (e.g., by adjusting one or both of the relative elevation angle and / or relative azimuth angle of the respective devices).

[0074]

[0075] 9A and 9B show top and side elevation views, respectively, of an exemplary user computing device 106. The user computing device 106 may include one or more antenna elements 200, 202 (e.g., arranged as a respective antenna array). With reference to FIG. 9A, the antenna elements 200, 202 may be configured to provide beam steering in the XY plane (illustrated by arrows 204, 206 and corresponding to relative azimuth angles). With reference to FIG. 9B, the antenna elements 200, 202 may be configured to provide beam steering in the ZY plane (illustrated by arrows 204, 206).

[0075]

[0076] FIG. 10 is a simplified schematic diagram of multiple antenna arrays 302 connected (e.g., with a front-end module) using respective feed lines 304. The antenna array 302 may be attached to a side 306 of a substrate 308, which may be formed from the polymer composition of the present invention. The antenna array 302 may include multiple vertically connected elements (e.g., as a mesh grid array). Thus, the antenna array 302 may extend generally parallel to the side 306 of the substrate 308. A shield may optionally be provided on the side 306 of the substrate 308, such that the antenna array 302 is located outside the shield relative to the substrate 308. The vertical spacing distances between the vertically connected elements of the antenna array 302 may correspond to the “feature size” of the antenna array 302. Thus, in some embodiments, these spacing distances may be relatively small (e.g., less than about 750 micrometers) such that the antenna array 302 is a “fine-pitch” antenna array 302.

[0076]

[0077] FIG. 11 shows a side elevation view of a coplanar waveguide antenna 400 configuration. One or more coplanar ground layers 402 may be arranged parallel to antenna elements 404 (e.g., patch antenna elements). Another ground layer 406 may be spaced apart from the antenna elements 404 by a substrate 408, which may be formed from the polymer composition of the present invention. One or more additional antenna elements 410 may be spaced apart from the antenna elements 404 by a second layer or substrate 412, which may also be formed from the polymer composition of the present invention. The dimensions “G” and “W” may correspond to the “feature size” of the antenna 400. The “G” dimension may correspond to the distance between the antenna element 404 and the coplanar ground layer 406. The “W” dimension may correspond to the width (e.g., line width) of the antenna element 404. Thus, in some embodiments, the dimensions “G” and “W” may be relatively small (e.g., less than about 750 micrometers) such that the antenna 400 is a “fine pitch” antenna 400.

[0077]

[0078] FIG. 12A illustrates an antenna array 500 according to another embodiment of the present disclosure. The antenna array 500 may include a substrate 510, which may be formed from the polymer composition of the present invention, and a plurality of antenna elements 520 formed thereon. The plurality of antenna elements 520 may be approximately equally sized in the X and / or Y directions (e.g., square or rectangular). The plurality of antenna elements 520 may be approximately equally spaced apart in the X and / or Y directions. The dimensions of and / or spacing between the antenna elements 520 may correspond to the “feature size” of the antenna array 500. Thus, in some embodiments, the dimensions and / or spacing may be relatively small (e.g., less than about 750 micrometers) such that the antenna array 500 is a “fine-pitch” antenna array 500. As illustrated by ovals 522, the number of columns of antenna elements 520 illustrated in FIG. 12 is provided by way of example only. Similarly, the number of rows of antenna elements 520 is provided by way of example only.

[0078]

[0079] The tunable antenna array 500 can be used, for example, in a base station to provide massive MIMO functionality (e.g., as described above with respect to FIG. 8). More specifically, radio frequency interactions between various elements can be controlled or tuned to provide multiple transmit and / or receive channels. Transmit power and / or receive sensitivity can be steered to focus or direct radio frequency signals, for example, as described with respect to the radio frequency signal 112 in FIG. 8. The tunable antenna array 500 can provide a large number of antenna elements 522 in a small footprint. For example, the tunable antenna 500 can have an average antenna element density of 1,000 or more antenna elements per square centimeter. Such a dense arrangement of antenna elements can increase the number of channels of MIMO functionality per unit area. For example, the number of channels may correspond to (e.g., be equal to or proportional to) the number of antenna elements.

[0079]

[0080] FIG. 12B illustrates an antenna array 540 formed with laser direct structuring, which can optionally be used to form antenna elements. The antenna array 540 can include multiple antenna elements 542 and multiple feed lines 544 connecting the antenna elements 542 (e.g., with other antenna elements 542, a front-end module, or other suitable components). The antenna elements 542 can have respective widths “w” and spacing distances “S1” and “S2” therebetween (e.g., in the X and Y directions, respectively). These dimensions can be selected to achieve 5G radio frequency communications at a desired 5G frequency. More specifically, the dimensions can be selected to tune the antenna array 540 for transmission and / or reception of data using radio frequency signals within the 5G frequency spectrum. The dimensions can be selected based on the material properties of the substrate. For example, one or more of “w,” “S1,” or “S2” can correspond to a multiple of the propagation wavelength (“λ”) of the desired frequency through the substrate material (e.g., nλ / 4, where n is an integer).

[0080]

[0081] As an example, λ can be calculated as follows:

[0081]

number

[0082] (where c is the speed of light in a vacuum,

[0083]

number

[0084] is the relative permittivity of the substrate (or surrounding material), and f is the desired frequency). 12C illustrates an exemplary antenna configuration 560 according to an embodiment of the present disclosure. The antenna configuration 560 can include multiple antenna elements 562 arranged on parallel long sides of a substrate 564, which can be formed from a polymer composition of the present invention. The various antenna elements 562 can have respective lengths "L" (and spacing distances therebetween) that tune the antenna configuration 560 for reception and / or transmission at a desired frequency and / or frequency range. More specifically, such dimensions can be selected based on the propagation wavelength λ at the desired frequency for the substrate material, as described above with reference to FIG. 12B, for example.

[0085] 13A-13C are simplified sequential illustrations of a laser direct structuring manufacturing process that can be used to form antenna elements and / or arrays according to aspects of the present disclosure. Referring to FIG. 13A, a substrate 600 can be formed from the polymer composition of the present invention using any desired technique (e.g., injection molding). In certain embodiments, as shown in FIG. 13B, a laser 602 can be used to activate a laser-activatable additive to form a circuit pattern 604 that can include one or more of the antenna elements and / or arrays. For example, the laser can melt conductive particles in the polymer composition to form the circuit pattern 604. Referring to FIG. 13C, the substrate 600 can be immersed in an electroless copper bath to plate the circuit pattern 604 and form the antenna elements, element arrays, other components, and / or conductive lines therebetween.

[0086]

[0084] The present invention can be better understood with reference to the following examples. [Example]

[0087] Test Method Melt viscosity: Melt viscosity (Pa·s) was measured using a Dynisco LCR7001 capillary rheometer at a shear rate of 400 s -1and at a temperature 15°C above the melt temperature (e.g., about 350°C), may be determined in accordance with ISO Test No. 11443:2014. The rheometer orifice (die) had a diameter of 1 mm, a length of 20 mm, an L / D ratio of 20.1, and an entrance angle of 180°. The barrel diameter was 9.55 mm + 0.005 mm, and the rod length was 233.4 mm.

[0088] Melting Temperature: The melting temperature ("Tm") may be determined by differential scanning calorimetry ("DSC") as known in the art. The melting temperature is the differential scanning calorimetry (DSC) peak melting temperature as determined by ISO Test No. 11357-3:2018. Based on the DSC procedure, samples were heated and cooled at 20°C per minute, as described in ISO Standard 10350, using DSC measurements performed on a TA Q2000 instrument.

[0089] Deflection Temperature Under Load ("DTUL"): Deflection temperature under load may be determined in accordance with ISO Test No. 75-2:2013 (technically equivalent to ASTM D648). More specifically, a test specimen sample 80 mm long, 10 mm thick, and 4 mm wide may be subjected to an edgewise three-point bend test at a specified load (maximum external fiber stress) of 1.8 megapascals. The specimen is lowered into a silicone oil bath and the temperature is increased at 2°C per minute until the specimen deflects 0.25 mm (0.32 mm per ISO Test No. 75-2:2013).

[0090] Tensile Modulus, Tensile Stress, and Tensile Elongation: Tensile properties may be tested according to ISO Test No. 527:2019 (technically equivalent to ASTM D638). Modulus and strength measurements may be performed on the same specimen sample, 80 mm long, 10 mm thick, and 4 mm wide. The test temperature may be 23°C, and the test speed may be 1 or 5 mm / min.

[0091] Flexural Modulus, Flexural Stress, and Flexural Elongation: Flexural properties may be tested according to ISO Test No. 178:2019 (technically equivalent to ASTM D790). This test may be performed on a support span of 64 mm. Testing may be performed at the center of an uncut ISO 3167 multipurpose bar. The test temperature may be 23°C, and the test speed may be 2 mm / min.

[0092] Charpy Impact Strength: Charpy properties may be tested according to ISO Test No. ISO 179-1:2010 (technically equivalent to ASTM D256-10, Method B). This test may be performed using a Type 1 specimen size (80 mm length, 10 mm width, and 4 mm thickness). When testing notched impact strength, the notch may be a Type A notch (0.25 mm base radius). Specimens may be cut from the center of a multipurpose bar using a single-tooth milling machine. The test temperature may be 23°C.

[0093] Dielectric Constant ("Dk") and Dissipation Factor ("Df"): The dielectric constant (or relative static permittivity) and dissipation factor are determined as described by Baker-Jarvis et al., IEEE Trans. on Dielectric and Electrical Insulation, 5(4), 571 (1998) and Krupka et al., Proc. th It is determined using a known split-post dielectric resonance method, such as that described in International Conference on Dielectric Materials: Measurements and Applications, IEEE Conference Publication No. 430 (September 1996). More specifically, a plate-shaped sample measuring 80 mm x 90 mm x 3 mm was inserted between two fixed dielectric resonators. The resonators measured the dielectric constant components at the surface of the specimen. Five samples were tested, and the average value was recorded. The split-post resonator can be used to perform dielectric measurements in the low gigahertz range, e.g., from 2 GHz to 1 GHz.

[0094] Thermal cycling test: The specimen is placed in a temperature-controlled chamber and heated / cooled within a temperature range of -30°C to 100°C. The specimen is first heated until it reaches a temperature of 100°C, at which point it is immediately cooled. When the temperature reaches -30°C, the specimen is immediately heated again until it reaches 100°C. 23 heating / cooling cycles may be performed over a 3-hour period.

[0095] Surface / Volume Resistivity: Surface and volume resistivity values ​​can be determined according to IEC 62631-3-1:2016 or ASTM D257-14. According to this procedure, a standard specimen (e.g., a 1-meter cube) is placed between two electrodes. A voltage is applied for 60 seconds, and the resistance is measured. Surface resistivity is the quotient of the potential gradient (in V / m) and the current per unit electrode length (in A / m), and generally represents the resistance to leakage current along the surface of an insulating material. Because the four edges of the electrode define a square, the length is reduced in the quotient to report surface resistivity in ohms, although it is common to see the more descriptive unit ohms per square. Volume resistivity is also determined as the ratio of the potential gradient parallel to the current flow in the material to the current density. In SI units, volume resistivity is numerically equal to the DC resistance (ohm·m or ohm·cm) between the opposing faces of a 1-meter cube of that material.

[0096] Example 1 Samples 1-4 are formed from various percentages of liquid crystal polymers ("LCP1" and "LCP2"), wollastonite fiber (Nyglos™ 8), carbon black pigment, carbon fiber, and lubricant (Glycolube™ P). LCP1 is formed from 60 mol.% HBA, 5 mol.% HNA, 12 mol.% BP, 17.5 mol.% TA, and 5 mol.% APAP. LCP2 is formed from 73 mol.% HBA and 27 mol.% HNA. Compounding was performed using an 18 mm single screw extruder. Parts were injection molded and samples were cut into plaques (60 mm x 60 mm).

[0097] [Table 1]

[0098]

[0095] Samples 1-4 were tested for thermal and mechanical properties, and the results are listed in Table 2 below.

[0099] [Table 2]

[0100]

[0096] Samples 3 and 4 were also subjected to the thermal cycle test described above. After the test, the dielectric loss tangents obtained for the samples were determined to be 0.021 and 0.015, respectively. Therefore, the ratios of the dielectric loss tangents of Samples 3 and 4 after the thermal cycle test to the initial dielectric loss tangents were 1.24 and 0.86, respectively. After the test, the dielectric constants obtained for the samples were determined to be 12.9 and 12.6, respectively. Therefore, the ratios of the dielectric constants of Samples 3 and 4 after the thermal cycle test to the initial dielectric constants were 0.98 and 1.01, respectively.

[0101] Samples 5-9 are formed from various percentages of liquid crystal polymers ("LCP1" and "LCP2"), Nyglos™ 8, carbon black pigment, graphite, and Glycolube™ P. Compounding was performed using an 18 mm single screw extruder. Parts were injection molded and samples were molded into plaques (60 mm x 60 mm).

[0102] [Table 3]

[0103]

[0098] Samples 5-9 were tested for thermal and mechanical properties, and the results are listed in Table 4 below.

[0104] [Table 4]

[0105]

[0099] Samples 5 to 7 were also subjected to the thermal cycle test described above. After the test, the dielectric loss tangents obtained for the samples were determined to be 0.0578, 0.0214, and 0.0098, respectively. Therefore, the ratios of the dielectric loss tangents after the thermal cycle test to the initial dielectric loss tangents of Samples 5, 6, and 7 were 1.17, 1.06, and 1.09, respectively. After the test, the dielectric constants obtained for the samples were determined to be 12.6, 8.9, and 6.3, respectively. Therefore, the ratios of the dielectric constants after the thermal cycle test to the initial dielectric constants of Samples 5, 6, and 7 were 1.0, 1.0, and 1.0, respectively.

[0106]

[0100] These and other modifications and variations of the present invention are intended to be understood as including all such modifications and variations without departing from the spirit and scope of the present invention. The present invention can be practiced by those skilled in the art without departing from the spirit or scope of the present invention. Furthermore, it should be understood that aspects of the various embodiments are interchangeable both in whole or in part. Furthermore, those skilled in the art will appreciate that the foregoing description is merely illustrative, and thus does not limit the invention as further described in such appended claims. The claims as filed are as follows: [Claim 1] A circuit structure comprising: a substrate comprising a polymeric composition, the polymeric composition comprising a conductive filler distributed within a polymeric matrix, the polymeric matrix containing at least one thermoplastic high performance polymer having a deflection under load of about 40°C or greater, determined according to ISO 75-2:2013 at a load of 1.8 MPa, and further wherein the polymeric composition exhibits a dielectric constant of about 4 or greater and a dissipation factor of about 0.3 or less, determined at a frequency of 2 GHz; one or more conductive elements disposed on the substrate; The circuit structure comprising: [Claim 2] 2. The circuit structure of claim 1, wherein the composition exhibits a dielectric constant after exposure to a temperature cycle of about −30° C. to about 100° C., wherein the ratio of the dielectric constant after the temperature cycle to the dielectric constant before the thermal cycle is about 0.8 or greater. [Claim 3] 2. The circuit structure of claim 1, wherein the composition exhibits a dielectric loss tangent after exposure to a temperature cycle of about −30° C. to about 100° C., wherein the ratio of the dielectric loss tangent after the temperature cycle to the dielectric loss tangent before the thermal cycle is about 1.3 or less. [Claim 4] 10. The circuit structure of claim 1, wherein the thermoplastic high performance polymer has a deflection under load of about 150°C to about 310°C determined according to ISO 75-2:2013 at a load of 1.8 MPa. [Claim 5] 2. The circuit structure according to claim 1, wherein the thermoplastic high performance polymer has a glass transition temperature of about 100°C to about 320°C and / or a melting temperature of about 200°C to about 410°C. [Claim 6] 10. The circuit structure of claim 1, wherein the thermoplastic high performance polymer comprises polyphenylene ether, polyphenylene oxide, polycarbonate, polyarylene sulfide, polyester, polyamide, polyimide, liquid crystal polymer, or a combination thereof. [Claim 7] The circuit structure of claim 6 , wherein the thermoplastic high performance polymer comprises a wholly aromatic liquid crystal polymer. [Claim 8] 8. The circuit structure of claim 7, wherein the liquid crystal polymer has a total amount of repeat units derived from naphthenic hydroxycarboxylic acids and / or naphthenic dicarboxylic acids of about 15 mol.% or less. [Claim 9] 9. The circuit structure according to claim 8, wherein the liquid crystal polymer contains HBA in an amount of about 30 mol.% to about 70 mol.%, IA and / or TA in an amount of about 2 mol.% to about 30 mol.%, and BP and / or HQ in an amount of about 2 mol.% to about 40 mol.%. [Claim 10] The polymer composition has a viscosity of about 1×10 determined at a temperature of about 20° C. according to ASTM D257-14 10 ohm·m ~ approx. 1×10 16 volume resistivity of ohm m and / or approximately 1 x 10 12ohm ~ approx. 1 x 10 18 10. The circuit structure of claim 1, exhibiting a surface resistivity in ohms. [Claim 11] The circuit structure of claim 1 , wherein the polymer composition is free of spinel crystals. [Claim 12] The polymer matrix comprises about 30 wt.% to about 80 wt.% of the polymer composition. The circuit structure of claim 1 comprising: [Claim 13] 10. The circuit structure of claim 1, wherein the conductive filler has a volume resistivity of less than about 1 ohm·cm. [Claim 14] The circuit structure of claim 1 , wherein the conductive filler comprises a carbon material. [Claim 15] 15. The circuit structure of claim 14, wherein the carbon material comprises graphite, carbon black, carbon fiber, graphene, carbon nanotubes, or a combination thereof. [Claim 16] 10. The circuit structure of claim 1, wherein the conductive filler is present in the polymer composition in an amount of about 0.5 to about 20 parts by weight per 100 parts by weight of the polymer matrix. [Claim 17] The circuit structure of claim 1 , wherein the polymer composition further comprises a mineral filler. [Claim 18] 18. The circuit structure of claim 17, wherein the mineral filler is present in the polymer composition in an amount of about 10 to about 80 parts by weight per 100 parts by weight of the polymer matrix. [Claim 19] 18. The circuit structure of claim 17, wherein the weight ratio of the mineral filler to the conductive filler ranges from about 2 to about 500. [Claim 20] 18. The circuit structure of claim 17, wherein the mineral filler comprises mineral particles, mineral fibers, or a combination thereof. [Claim 21] 21. The circuit structure of claim 20, wherein the mineral particles comprise talc, mica, or a combination thereof. [Claim 22] 21. The circuit structure of claim 20, wherein the mineral fibers comprise wollastonite. [Claim 23] 23. The circuit structure of claim 22, wherein the mineral fibers have a median diameter of about 1 to about 35 micrometers. [Claim 24] 23. The circuit structure of claim 22, wherein the mineral fibers have an aspect ratio of about 1 to about 50. [Claim 25] The polymer composition is -1 10. The circuit structure of claim 1, wherein the composition has a melt viscosity of about 10 to about 250 Pa·s, as determined according to ISO Test No. 11443:2014, at a shear rate of 100°C and a temperature 15°C above the melting temperature of the composition. [Claim 26] The circuit structure of claim 1 , wherein the conductive element comprises copper, nickel, or a combination thereof. [Claim 27] shaping the substrate; forming a pattern on a surface of a substrate; subjecting the patterned surface to a plating process to form said conductive elements. 27. A method for forming the circuit structure according to claim 1, comprising: [Claim 28] 28. The method of claim 27, wherein the pattern is formed by a process including laser ablation. [Claim 29] 28. The method of claim 27, further comprising forming a seed layer on the surface prior to the plating process. [Claim 30] 28. The method of claim 27, wherein the plating process comprises electroless plating. [Claim 31] An antenna system including the circuit structure according to any one of claims 1 to 26, The antenna system, wherein the conductive element is an antenna element configured to transmit and receive radio frequency signals. [Claim 32] 32. The antenna system of claim 31 , wherein the radio frequency signal is a 5G signal. [Claim 33] 32. The antenna system of claim 31, wherein the at least one antenna element has a feature size of less than about 1,500 micrometers. [Claim 34] 32. The antenna system of claim 31, wherein the antenna elements are spaced apart by a spacing distance of less than about 1,500 micrometers. [Claim 35] 32. The antenna system of claim 31, wherein at least 16 antenna elements are disposed on the substrate. [Claim 36] 32. The antenna system of claim 31, wherein the antenna elements are arranged in an array. [Claim 37] 37. The antenna system of claim 36, wherein the array is configured for at least eight transmit channels and at least eight receive channels. [Claim 38] 37. The antenna system of claim 36, wherein the array has an average antenna element density of greater than 1,000 antenna elements per square centimeter.

Claims

1. A circuit structure comprising:

1. A substrate comprising a polymeric composition, the polymeric composition comprising a conductive filler distributed within a polymeric matrix, the polymeric matrix containing at least one thermoplastic high performance polymer having a deflection under load of about 40°C or greater, determined in accordance with ISO 75-2:2013 at a load of 1.8 MPa, the polymeric composition exhibiting a dielectric constant of about 4 or greater and a dissipation factor of about 0.3 or less, determined at a frequency of 2 GHz, and a dielectric constant of about 4.2 x 10, determined in accordance with ASTM D257-14. １５ ohm to approximately 1 x 10 １８ the substrate exhibiting a surface resistivity in ohms; and one or more conductive elements disposed on the substrate; The circuit structure comprising:

2. 10. The circuit structure of claim 1, wherein the composition exhibits a dielectric constant after exposure to a temperature cycle of about −30° C. to about 100° C., wherein the ratio of the dielectric constant after the temperature cycle to the dielectric constant before the thermal cycle is about 0.8 or greater.

3. 2. The circuit structure of claim 1, wherein the composition exhibits a dielectric loss tangent after exposure to a temperature cycle of about −30° C. to about 100° C., wherein the ratio of the dielectric loss tangent after the temperature cycle to the dielectric loss tangent before the thermal cycle is about 1.3 or less.

4. 10. The circuit structure of claim 1, wherein the thermoplastic high performance polymer has a deflection under load of about 150°C to about 310°C determined according to ISO 75-2:2013 at a load of 1.8 MPa.

5. 10. The circuit structure of claim 1, wherein the thermoplastic high performance polymer has a glass transition temperature of about 100.degree. C. to about 320.degree. C. and / or a melting temperature of about 200.degree. C. to about 410.degree.

6. 10. The circuit structure of claim 1, wherein the thermoplastic high performance polymer comprises polyphenylene ether, polyphenylene oxide, polycarbonate, polyarylene sulfide, polyester, polyamide, polyimide, liquid crystal polymer, or a combination thereof.

7. The circuit structure of claim 6 , wherein the thermoplastic high performance polymer comprises a wholly aromatic liquid crystal polymer.

8. 8. The circuit structure of claim 7, wherein the liquid crystal polymer has a total amount of repeat units derived from naphthenic hydroxycarboxylic acids and / or naphthenic dicarboxylic acids of about 15 mol. % or less.

9. 9. The circuit structure according to claim 8, wherein the liquid crystal polymer contains HBA in an amount of about 30 mol.% to about 70 mol.%, IA and / or TA in an amount of about 2 mol.% to about 30 mol.%, and BP and / or HQ in an amount of about 2 mol.% to about 40 mol.%.

10. The polymer composition has a viscosity of about 1×10 determined at a temperature of about 20° C. according to ASTM D257-14 １０ ohm-m to approximately 1 x 10 １６ 10. The circuit structure of claim 1, exhibiting a volume resistivity of ohm-m.

11. The circuit structure of claim 1 , wherein the polymer composition is free of spinel crystals.

12. 10. The circuit structure of claim 1, wherein the polymer matrix comprises from about 30 wt. % to about 80 wt. % of the polymer composition.

13. 10. The circuit structure of claim 1, wherein the conductive filler has a volume resistivity of less than about 1 ohm-cm.

14. The circuit structure of claim 1 , wherein the conductive filler comprises a carbon material.

15. 15. The circuit structure of claim 14, wherein the carbon material comprises graphite, carbon black, carbon fiber, graphene, carbon nanotubes, or a combination thereof.

16. 10. The circuit structure of claim 1, wherein the conductive filler is present in the polymer composition in an amount of about 0.5 to about 20 parts by weight per 100 parts by weight of the polymer matrix.

17. The circuit structure of claim 1 , wherein the polymer composition further comprises a mineral filler.

18. 18. The circuit structure of claim 17, wherein the mineral filler is present in the polymer composition in an amount of about 10 to about 80 parts by weight per 100 parts by weight of the polymer matrix.

19. 18. The circuit structure of claim 17, wherein the weight ratio of said mineral filler to said conductive filler ranges from about 2 to about 500.

20. 18. The circuit structure of claim 17, wherein the mineral filler comprises mineral particles, mineral fibers, or a combination thereof.

21. 21. The circuit structure of claim 20, wherein the mineral particles comprise talc, mica, or a combination thereof.

22. 21. The circuit structure of claim 20, wherein the mineral fibers comprise wollastonite.

23. 23. The circuit structure of claim 22, wherein the mineral fibers have a median diameter of about 1 to about 35 micrometers.

24. 23. The circuit structure of claim 22, wherein said mineral fibers have an aspect ratio of about 1 to about 50.

25. The polymer composition is －１ 10. The circuit structure of claim 1, wherein the composition has a melt viscosity of about 10 to about 250 Pa·s as determined in accordance with ISO Test No. 11443:2014 at a shear rate of 100 to 150 Pa·s and a temperature 15° C. above the melting temperature of the composition.

26. The circuit structure of claim 1 , wherein the conductive elements comprise copper, nickel, or a combination thereof.

27. shaping the substrate; forming a pattern on a surface of a substrate; subjecting the patterned surface to a plating process to form said conductive elements. A method for forming the circuit structure of any preceding claim, comprising:

28. 28. The method of claim 27, wherein the pattern is formed by a process including laser ablation.

29. 30. The method of claim 27, further comprising forming a seed layer on the surface prior to the plating process.

30. 28. The method of claim 27, wherein the plating process comprises electroless plating.

31. An antenna system including the circuit structure according to any one of claims 1 to 26, The antenna system, wherein the conductive element is an antenna element configured to transmit and receive radio frequency signals.

32. 32. The antenna system of claim 31 , wherein the radio frequency signal is a 5G signal.

33. 32. The antenna system of claim 31 , wherein the at least one antenna element has a feature size of less than about 1,500 micrometers.

34. 32. The antenna system of claim 31 , wherein the antenna elements are spaced apart by a spacing distance of less than about 1,500 micrometers.

35. 32. The antenna system of claim 31, wherein at least 16 antenna elements are disposed on the substrate.

36. 32. The antenna system of claim 31, wherein the antenna elements are arranged in an array.

37. 37. The antenna system of claim 36, wherein the array is configured for at least eight transmit channels and at least eight receive channels.

38. 37. The antenna system of claim 36, wherein said array has an average antenna element density of greater than 1,000 antenna elements per square centimeter.

39. The circuit structure of claim 8, wherein the liquid crystal polymer contains repeat units derived from 4-hydroxybenzoic acid in an amount of about 30 mol. % to about 90 mol. % of the polymer and repeat units derived from 6-hydroxy-2-naphthoic acid in an amount of about 1 mol. % to about 8 mol. % of the polymer.

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