Antenna cover including a polymer composition having a low dielectric constant and a dielectric tangent

Abstract

The present disclosure relates to an antenna cover including a layer containing a polymer composition. The polymer composition includes a polymer matrix containing at least one polymer having a glass transition temperature of about 50°C or higher, the polymer matrix comprising about 30 wt.% to about 90 wt.% of the polymer composition. The polymer composition exhibits a relative permittivity of about 4 or less and a dielectric loss tangent of about 0.02 or less, determined at a frequency of 2 GHz. The disclosure further relates to a 5G radio frequency communication device and a base station including the aforementioned antenna cover.

Description

Technical Field

[0001] Cross - reference to related applications

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 933,563, filed on November 11, 2019, which is incorporated herein by reference in its entirety.

Background Art

[0002]

[0002] High - frequency wireless signal communication is becoming increasingly popular. For example, due to the demand for faster data transmission for wireless smartphone connectivity, the demand for high - frequency components configured to operate at 5G spectrum frequencies is increasing. The trend towards miniaturization has led to an increase in the number of electronic components in the compact areas of user computing devices (e.g., smartphones, laptops). To shield such electronic components, a shielding layer can be used. However, an antenna cannot function properly from under the shielding layer. Therefore, the shielding layer can be placed over various antennas and can include a "window" of a radio - frequency transparent material that allows the antenna to transmit and receive radio - frequency signals through the shielding layer. However, current materials for such "windows" do not exhibit good characteristics. For example, certain materials do not provide stable performance, and other materials tend to be difficult to process.

Summary of the Invention

Problems to be Solved by the Invention

[0003]

[0003] Therefore, there is a need for a polymer composition for antenna covers and their windows that has a relatively low relative permittivity and a relatively low dielectric tangent, but still maintains excellent mechanical properties and processability (e.g., low viscosity).

Means for Solving the Problems

[0004] According to one embodiment of the present invention, an antenna cover including a layer containing a polymer composition is disclosed. The polymer composition includes a polymer matrix containing at least one polymer having a glass transition temperature of about 50 °C or higher, the polymer matrix constituting about 30 wt.% to about 90 wt.% of the polymer composition, and further the polymer composition exhibits a relative permittivity of about 4 or less and a dielectric tangent of about 0.02 or less determined at a frequency of 2 GHz.

[0005] According to another embodiment of the present invention, a 5G radio frequency communication device including a substrate, an antenna element coupled to the substrate, and an antenna cover disposed on the substrate is disclosed. The antenna cover may include a layer containing a polymer composition. The 5G radio frequency communication system may include radio frequency components communicatively coupled to the antenna element and configured to operate at about 2.5 GHz or higher. The polymer composition includes a polymer matrix containing at least one polymer having a glass transition temperature of about 50 °C or higher, the polymer matrix constituting about 30 wt.% to about 90 wt.% of the polymer composition, and further the polymer composition exhibits a relative permittivity of about 4 or less and a dielectric tangent of about 0.02 or less determined at a frequency of 2 GHz.

[0006] According to another embodiment of the present invention, a base station including an antenna array and an antenna cover disposed on the antenna array is disclosed. The antenna cover includes a layer containing a polymer composition including a polymer matrix containing at least one polymer having a glass transition temperature of about 50 °C or higher, the polymer matrix constituting about 30 wt.% to about 90 wt.% of the polymer composition, and further the polymer composition exhibits a relative permittivity of about 4 or less and a dielectric tangent of about 0.02 or less determined at a frequency of 2 GHz.

[0007] Other features and aspects of the present invention are discussed in more detail below.

[0008] A complete and enabling disclosure of the invention is described in more detail in the remainder of this specification, including reference to the accompanying drawings, which include the best mode thereof for those of ordinary skill in the art.

Brief Description of the Drawings

[0008]

Figure 1

[0009] FIG. is a diagram of a 5G communication system including a base station, one or more relay stations, one or more user computing devices, and one or more or more Wi-Fi repeaters according to an aspect of the present disclosure.

Figure 2A

[0010] FIG. is a top view of an exemplary user computing device including a 5G antenna according to an aspect of the present disclosure.

Figure 2B

[0011] FIG. is a side view of the exemplary user computing device of FIG. 2A including a 5G antenna according to an aspect of the present disclosure.

Figure 3

[0012] FIG. is a side view of an antenna cover for providing a shield to other electronic components formed on a substrate, having layers such as a window and a conductive layer of a polymer composition for an antenna.

Figure 4A

[0013] FIG. is a simplified schematic side view of a base station according to an aspect of the present disclosure.

Figure 4B

[0014] FIG. is a first side view of an exemplary MIMO antenna array of the base station of FIG. 4A.

Figure 4C

[0015] FIG. is a second side view of an exemplary MIMO antenna array of the base station of FIG. 4A.

Mode for Carrying Out the Invention

[0009]

[0016] It will be understood by those of ordinary skill in the art that this discussion is merely illustrative of exemplary embodiments and is not intended to limit the broader aspects of the present disclosure.

[0017] Generally, the present invention relates to an antenna cover including a polymer composition. The inventors have found that the specific polymer composition disclosed herein provides not only improved dielectric properties but also improved adhesion to other layers, and thus can provide good performance as a shielding layer when disposed on an antenna. In particular, the polymer composition includes a polymer matrix containing at least one polymer having a glass transition temperature of about 50 °C or higher, and the polymer composition exhibits a relative permittivity of about 4 or less and a dielectric tangent of about 0.02 or less determined at a frequency of 2 GHz.

[0010]

[0018] By providing a polymer composition having such relatively low dielectric properties, it is possible to assist in minimizing signal loss and improving the performance related to signal transmission and reception when used in specific applications such as signal transmission applications, particularly those related to 5G communication. In this regard, determined by the split post resonance method and IEC60250 at a frequency of 2 GHz, the relative permittivity is about 4 or less, in some embodiments about 3.8 or less, in some embodiments about 1 to about 3.8, in some embodiments about 2.5 to about 3.8, in some embodiments about 2.6 to about 3.1, or in other embodiments, determined by the split post resonance method and IEC60250 at a frequency of 2 GHz, it may be about 3.3 to 3.8. Further, the dielectric tangent, which is a measured value of the energy loss rate, is about 0.02 or less determined by the split post resonance method and IEC60250 at a frequency of 2 GHz, in some embodiments about 0.015 or less, in some embodiments about 0.01 or less, in some embodiments about 0.001 to about 0.01, in some embodiments about 0.003 to about 0.01, in some embodiments about 0.004 to about 0.01, in some embodiments about 0.0055 to about 0.09, in some embodiments about 0.007 to about 0.009.

[0011]

[0019] Here, various embodiments of the present invention will be described in more detail. I. Polymer Composition A. Polymer Matrix

[0020] Generally, any of various polymers or combinations of polymers may be utilized in the polymer matrix. For example, the polymer may have semi-crystalline or crystalline properties. In one embodiment, the polymer may be semi-crystalline. In another embodiment, the polymer may be crystalline. Further, in one embodiment, the polymer may be an aromatic polymer.

[0012]

[0021] Suitable polymers may include thermoplastic polymers. For example, these polymers include, for example, polyesters (e.g., polyethylene terephthalate, polybutylene terephthalate, liquid crystal polymers), polyarylene sulfides, polyetherimides, polyphenylene oxides, polyaryl ketones (e.g., polyether ether ketone, polyether ketone ketone, etc.), polycarbonates, etc., and blends thereof.

[0013]

[0022] Irrespective of that, the polymer may generally be regarded as a "high-performance" polymer and thus may have a relatively high glass transition temperature and / or a high melting temperature. Accordingly, such high-performance polymers can impart a substantial degree of heat resistance to the polymer composition. For example, the polymer may have a glass transition temperature of about 50°C or higher, in some embodiments from about 50°C to about 250°C, in some embodiments from about 50°C to about 150°C, and in some embodiments from about 50°C to about 100°C. The polymer may also have a melting temperature of about 200°C or higher, in some embodiments about 210°C or higher, in some embodiments from about 210°C to about 400°C, and in some embodiments from about 220°C to about 380°C. The glass transition temperature and the melting temperature may be determined using differential scanning calorimetry ("DSC") as is well known in the art, for example, by ISO test No. 11357-2:2013 (glass transition temperature) and 11357-3:2011 (melting temperature).

[0014]

[0023] An example of a suitable semi-crystalline aromatic polymer is an aromatic polyester which is a condensation product of, for example, an aromatic dicarboxylic acid having 8 to 14 carbon atoms and at least one diol. Suitable diols include, for example, neopentyl glycol, cyclohexanedimethanol, 2,2-dimethyl-1,3-propanediol, and aliphatic glycols of the formula HO(CH2) n OH (wherein 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, etc., and combinations thereof. A condensed ring may be present, such as in 1,4-, or 1,5-, or 2,6-naphthalenedicarboxylic acid. Specific examples of such aromatic polyesters 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 copolymers and mixtures described above.

[0015]

[0024] The polyester may have a crystallinity of about 38% or more, in some embodiments about 40% or more, and in some embodiments about 45% or more. The crystallinity of the polyester may generally be about 70% or less, in some embodiments about 65% or less, and in some embodiments about 60% or less. The percent crystallinity may be determined using differential scanning calorimetry (DSC). Such analysis may be performed using a Pyris 6 DSC instrument manufactured by PerkinElmer. A detailed description of the calculations is available from Sichina, W. J. "DSC as problem solving tool: measurement of percent crystallinity of thermoplastics." Thermal Analysis Application Note (2000).

[0016]

[0025] In one particular embodiment, the polyester may include polybutylene terephthalate. In another particular embodiment, the polyester may include polyethylene terephthalate. In a further particular embodiment, the polyester may include a combination of polybutylene terephthalate and polyethylene terephthalate. In this regard, when used in combination, the weight ratio of polybutylene terephthalate to polyethylene terephthalate may be greater than 1, for example about 1.3 or more, for example about 1.5 or more, for example about 1.7 or more.

[0017]

[0026] Furthermore, modified products or copolymers of polyethylene terephthalate polymers and / or polybutylene terephthalate polymers may also be used. For example, in one embodiment, modified acids or modified diols may be used to produce modified polyethylene terephthalate polymers and / or modified polybutylene terephthalate polymers. As used herein, the terms "modified acid" and "modified diol" are intended to define compounds that can each form part of the acid and diol repeating units of the polyester and that can modify the polyester to reduce its crystallinity or render the polyester amorphous. Of course, the polyester may be unmodified and contain no modified acid or modified diol. In any case, examples of modified acid components 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, in many cases, it is preferred to use these functional acid derivatives such as dimethyl, diethyl or dipropyl esters of dicarboxylic acids. In practical applications, 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 - hydroxyethylbisphenol A], 4,4’ - bis(2 - hydroxyethoxy)diphenyl sulfide [bis - hydroxyethylbisphenol S], and diols containing one or more oxygen atoms in the chain, such as diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, etc. Generally, these diols contain 2 to 18 carbon atoms, and in some embodiments, 2 to 8 carbon atoms. Alicyclic diols can be utilized in their cis or trans configurations, or as a mixture of both forms.

[0018]

[0027] In some embodiments, at least one polyester or copolyester present in the polymer composition may have an intrinsic viscosity (IV) of about 0.5 to about 0.9 dL / g, such as about 0.5 to about 0.8 dL / g. In one embodiment, for example, the intrinsic viscosity of the polyester is about 0.65 to about 0.8 dL / g.

[0019]

[0028] Polyarylene sulfide is also a suitable semi - crystalline aromatic polymer. The polyarylene sulfide utilized in the composition generally has the formula: -[(Ar 1 ) n -X] m -[(Ar 2 ) i -Y] j -[(Ar3 ) k -Z] l -[(Ar 4 ) o -W] p - (wherein Ar 1 、Ar 2 、Ar 3 and Ar 4 are independently arylene units having 6 to 18 carbon atoms; W, X, Y and Z are independently divalent linking groups selected from -SO2-, -S-, -SO-, -CO-, -O-, -C(O)O- or alkylene or alkylidene groups having 1 to 6 carbon atoms, wherein at least one of the linking groups is -S; n, m, i, j, k, l, o and p are independently 0, 1, 2, 3 or 4 on the premise that their sum is 2 or more) having a repeating unit of.

[0020]

[0029] The arylene units Ar 1 、Ar 2 、Ar 3 and Ar 4 may be optionally substituted or unsubstituted. Advantageous arylene units are phenylene, biphenylene, naphthylene, anthracene and phenanthrene. The polyarylene sulfide typically contains arylene sulfide (-S-) units higher than about 30 mol%, higher than about 50 mol%, or higher than about 70 mol%. For example, the polyarylene sulfide may contain at least 85 mol% of sulfide linkages directly bonded to two aromatic rings. In one particular embodiment, the polyarylene sulfide is a polyphenylene sulfide defined herein as containing the phenylene sulfide structure -(C6H4-S) n -(wherein n is an integer of 1 or more).

[0021]

[0030] Synthesis techniques that may be used in the production of polyarylene sulfide are generally known in the art. By way of example, a method for producing polyarylene sulfide may include reacting a material that imparts hydrosulfide ions (e.g., an alkali metal sulfide) with a dihaloaromatic compound in an organic amide solvent. The alkali metal sulfide may be, for example, lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide, or a mixture thereof. When the alkali metal sulfide is a hydrate or an aqueous mixture, the alkali metal sulfide may be treated by a dehydration operation prior to the polymerization reaction. The alkali metal sulfide may also be generated in situ. Further, a small amount of an alkali metal hydroxide may be included during the reaction to remove impurities such as an alkali metal polysulfide or an alkali metal thiosulfate that may be present in very small amounts along with the alkali metal sulfide, or (e.g., to convert such impurities to harmless materials) react them.

[0022]

[0031] The dihaloaromatic compound may be, without limitation, o-dihalobenzene, m-dihalobenzene, p-dihalobenzene, dihalotoluene, dihalonaphthalene, methoxy-dihalobenzene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihalodiphenyl sulfone, dihalodiphenyl sulfoxide or dihalodiphenyl ketone. The dihaloaromatic compound can be used either alone or in any combination thereof. Specific exemplary dihaloaromatic compounds include, without limitation, p-dichlorobenzene; m-dichlorobenzene; o-dichlorobenzene; 2,5-dichlorotoluene; 1,4-dibromobenzene; 1,4-dichloronaphthalene; 1-methoxy-2,5-dichlorobenzene; 4,4'-dichlorobiphenyl; 3,5-dichlorobenzoic acid; 4,4'-dichlorodiphenyl ether; 4,4'-dichlorodiphenyl sulfone; 4,4'-dichlorodiphenyl sulfoxide; and 4,4'-dichlorodiphenyl ketone. The halogen atom may be fluorine, chlorine, bromine, or iodine, and the two halogen atoms in the same dihaloaromatic compound may be the same or different from each other. In one embodiment, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, or a mixture of two or more of these compounds is used as the dihaloaromatic compound. As is known in the art, a monohalo compound (not necessarily an aromatic compound) can also be used in combination with the dihaloaromatic compound to form the end groups of the polyarylene sulfide or to adjust the polymerization reaction and / or the molecular weight of the polyarylene sulfide.

[0023]

[0032] The polyarylene sulfide may be a homopolymer or a copolymer. For example, by a selective combination of dihaloaromatic compounds, a polyarylene sulfide copolymer 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 formula:

[0024]

Chemical formula

[0025] Segments having the structure of, and the formula:

[0026]

Chem.

[0027] Segments having the structure of, or the formula:

[0028]

Chem.

[0029] A polyarylene sulfide copolymer containing segments having the structure of can be formed.

[0033] The polyarylene sulfide may be linear, semi-linear, branched, or crosslinked. Linear polyarylene sulfide typically contains 80 mol% or more of the repeating unit -(Ar-S)-. Such linear polymers may also contain a small amount of branched or crosslinked units, but the amount of branched or crosslinked units is typically less than about 1 mol% of the total monomer units of the polyarylene sulfide. The linear polyarylene sulfide polymer may be a random copolymer or a block copolymer containing the above-mentioned repeating units. The semi-linear polyarylene sulfide may similarly 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. As an example, the monomer components used for the formation of the semi-linear polyarylene sulfide may include a certain amount of polyhaloaromatic compounds having two or more halogen substituents per molecule, which are available for the preparation of branched polymers. Such monomers have the formula R’X n(Wherein each X is selected from chlorine, bromine and iodine, n is an integer of 3 to 6, R' is a polyvalent aromatic group of valence n which may have up to about 4 methyl substituents, and the total number of carbon atoms in R' is in the range of 6 to about 16) can be represented by. Examples of some polyhaloaromatic compounds substituted with more than two halogens per molecule that can be used in the formation of semi-linear polyarylene sulfide 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, etc., and mixtures thereof.

[0030]

[0034] Another suitable semi-crystalline aromatic polymer that may be utilized in the present invention is polyaryletherketone. Polyaryletherketone is a semi-crystalline polymer having a relatively high melting temperature of about 300 °C to about 400 °C, in some embodiments about 310 °C to about 390 °C, and in some embodiments about 330 °C to about 380 °C, etc. The glass transition temperature may similarly be about 110 °C to about 200 °C. Particularly suitable polyaryletherketones mainly contain phenyl moieties in combination with ketone and / or ether moieties. Examples of such polymers include polyetheretherketone ("PEEK"), polyetherketone ("PEK"), polyetherketoneketone ("PEKK"), polyetherketoneetherketoneketone ("PEKEKK"), polyetheretherketoneketone ("PEEKK"), polyether-diphenyl-ether-ether-diphenyl-ether-phenyl-ketone-phenyl, etc., as well as blends and copolymers thereof.

[0031]

[0035] In addition to the polymers mentioned above, crystalline polymers may also be used in the polymer composition. Particularly preferred are liquid crystal polymers having a high degree of crystallinity that enable effective filling of small spaces in the mold. Liquid crystal polymers generally have a rod-like structure and are classified as "thermotropic" as long as they can exhibit crystalline behavior in their molten state (e.g., thermotropic nematic state). These polymers may generally be referred to as polyesters. The polymers 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. The liquid crystal polymer may contain, for example, one or more aromatic ester repeating units typically in an amount of about 60 mol.% to about 99.9 mol.% of the polymer, in some embodiments about 70 mol.% to about 99.5 mol.%, and in some embodiments about 80 mol.% to about 99 mol.%. The aromatic ester repeating unit generally has the following formula (I):

[0032]

Chemical formula

[0033] (wherein 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 condensed 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)) and can be represented by.

[0034]

[0036] Typically, at least one of Y1 and Y2 is C(O). Examples of such aromatic ester repeating units include, for example, aromatic dicarboxylic acid repeating units (where Y1 and Y2 in formula I are C(O)), aromatic hydroxycarboxylic acid repeating units (where Y1 in formula I is O and Y2 is C(O)), and various combinations thereof.

[0035]

[0037] For example, 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, etc., and aromatic dicarboxylic acid repeating units derived from these aromatic dicarboxylic acids such as their alkyl, alkoxy, aryl, and halogen substituents, and combinations thereof may be utilized. Particularly preferred aromatic dicarboxylic acids include, for example, terephthalic acid ("TA"), isophthalic acid ("IA"), and 2,6-naphthalenedicarboxylic acid ("NDA"). When utilized, the repeating units derived from the aromatic dicarboxylic acid (e.g., IA, TA, and / or NDA) typically constitute from about 5 mol.% to about 60 mol.% of the polymer, in some embodiments from about 10 mol.% to about 55 mol.%, and in some embodiments from about 15 mol.% to about 50 mol.%.

[0036]

[0038] In addition, aromatic hydroxycarboxylic acid repeating 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 their alkyl, alkoxy, aryl, and halogen substituents, and combinations thereof may be used. Particularly preferred aromatic hydroxycarboxylic acids are 4-hydroxybenzoic acid ("HBA") and 6-hydroxy-2-naphthoic acid ("HNA"). When used, the repeating units derived from hydroxycarboxylic acids (e.g., HBA and / or HNA) typically constitute from about 10 mol.% to about 85 mol.% of the polymer, in some embodiments from about 20 mol.% to about 80 mol.%, and in some embodiments from about 25 mol.% to about 75 mol.%.

[0037]

[0039] Other repeating units can also be used in the polymer. For example, in certain embodiments, 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, etc., as well as repeating units derived from aromatic diols such as their alkyl, alkoxy, aryl, and halogen substituents, and combinations thereof, may be used. Particularly preferred aromatic diols include, for example, hydroquinone ("HQ") and 4,4'-biphenol ("BP"). When used, the repeating units derived from the aromatic diol (e.g., HQ and / or BP) typically constitute about 1 mol.% to about 30 mol.% of the polymer, in some embodiments about 2 mol.% to about 25 mol.%, and in some embodiments about 5 mol.% to about 20 mol.%. Also, repeating units 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 be used. When used, the repeating units derived from the aromatic amide (e.g., APAP) and / or aromatic amine (e.g., AP) typically constitute about 0.1 mol.% to about 20 mol.% of the polymer, in some embodiments about 0.5 mol.% to about 15 mol.%, and in some embodiments about 1 mol.% to about 10 mol.%. It should also be understood that various other monomer repeating units may be introduced into the polymer. For example, in certain embodiments, the polymer may contain one or more repeating units derived from non-aromatic monomers such as aliphatic or alicyclic hydroxycarboxylic acids, dicarboxylic acids, diols, amides, amines, etc. Of course, in other embodiments, the polymer may be "wholly aromatic" in that it does not contain repeating units derived from non-aromatic (e.g., aliphatic or alicyclic) monomers.

[0038]

[0040] Although not necessarily required, the liquid crystal polymer may be a "high naphthene" polymer as long as it contains a relatively high content of repeating 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 repeating units derived from naphthenic hydroxycarboxylic acids and / or dicarboxylic acids (e.g., NDA, HNA or a combination of HNA and NDA) may be about 10 mol.% or more of the polymer, in some embodiments about 20 mol.% or more, in some embodiments about 30 mol.% to about 95 mol.%, and in some embodiments about 40 mol.% to about 80 mol.%. In one particular embodiment, for example, the repeating units derived from naphthalene-2,6-dicarboxylic acid ("NDA") may constitute about 10 mol.% or more of the polymer, in some embodiments about 12 mol.% or more, in some embodiments about 15 mol.% to about 40 mol.%, and in some embodiments about 18 mol.% to about 35 mol.%.

[0039]

[0041] Furthermore, although not necessarily required, the liquid crystal polymer may be a "low naphthene" polymer as long as it contains a minimal content of repeating 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 repeating units derived from naphthenic hydroxycarboxylic acids and / or dicarboxylic acids (e.g., NDA, HNA or a combination of HNA and NDA) is typically 30 mol.% or less of the polymer, in some embodiments about 15 mol.% or less, in some embodiments about 10 mol.% or less, in some embodiments about 8 mol.% or less, and in some embodiments 0 mol.% to about 5 mol.% (e.g., 0 mol.%). It is believed that the resulting "low naphthene" polymer can still exhibit good thermal and mechanical properties despite the absence of high levels of conventional naphthenic acids.

[0040]

[0042] In one particular embodiment, the liquid crystal polymer may be formed from repeating units derived from 4-hydroxybenzoic acid (“HBA”), and terephthalic acid (“TA”) and / or isophthalic acid (“IA”), and various other optional components. The repeating units derived from 4-hydroxybenzoic acid (“HBA”) may constitute from about 10 mol.% to about 80 mol.% of the polymer, in some embodiments from about 30 mol.% to about 75 mol.%, and in some embodiments from about 45 mol.% to about 70 mol.%. Similarly, the repeating units derived from terephthalic acid (“TA”) and / or isophthalic acid (“IA”) may constitute from about 5 mol.% to about 40 mol.% of the polymer, in some embodiments from about 10 mol.% to about 35 mol.%, and in some embodiments from about 15 mol.% to about 35 mol.%. Also, repeating units derived from 4,4'-biphenol (“BP”) and / or hydroquinone (“HQ”) in an amount of from about 1 mol.% to about 30 mol.% of the polymer, in some embodiments from about 2 mol.% to about 25 mol.%, and in some embodiments from about 5 mol.% to about 20 mol.% may be utilized. Other possible repeating units include those derived from 6-hydroxy-2-naphthoic acid (“HNA”), 2,6-naphthalenedicarboxylic acid (“NDA”), and / or acetaminophen (“APAP”). For example, in certain embodiments, the repeating units derived from HNA, NDA, and / or APAP, if utilized, may each constitute from about 1 mol.% to about 35 mol.%, in some embodiments from about 2 mol.% to about 30 mol.%, and in some embodiments from about 3 mol.% to about 25 mol.%.

[0041]

[0043] In certain embodiments, it may be desirable to utilize a blend of polymers in a polymer matrix. For example, the polymer matrix may contain a first polymer having a crystallization rate faster than that of a second polymer. In one embodiment, the first polymer may include polyethylene terephthalate, and the second polymer may include polybutylene terephthalate polymer. Combining polymers having different crystallization rates can provide various advantages and benefits. For example, a more slowly crystallizing polymer (e.g., polybutylene terephthalate) tends to migrate to the surface of the part, which can result in good surface gloss and aesthetics, while a more rapidly crystallizing polymer (e.g., polyethylene terephthalate) can enhance mechanical properties. When such a blend is utilized, it is typically desired that the first polymer be present in a greater amount than the second polymer. For example, the weight ratio of the first polymer to the second polymer may be from about 1 to about 20, in some embodiments from about 2 to about 15, and in some embodiments from about 3 to about 10. For example, the first polymer may constitute from about 10 wt.% to about 40 wt.%, in some embodiments from about 15 wt.% to about 35 wt.%, and in some embodiments from about 20 wt.% to about 30 wt.% of the polymer composition, while the second polymer may constitute from about 1 wt.% to about 10 wt.%, in some embodiments from about 2 wt.% to about 9 wt.%, and in some embodiments from about 3 wt.% to about 8 wt.%.

[0042]

[0044] The polymers in the polymer matrix may be present in an amount of about 30 wt.% or more, in some embodiments about 40 wt.% or more, in some embodiments from about 45 wt.% to about 90 wt.%, and in some embodiments from about 50 wt.% to about 85 wt.%, based on the weight of the polymer composition. In one embodiment, at least one polymer may be present in the polymer matrix at the aforementioned concentrations.

[0043] B. Impact modifier

[0045] The polymer composition may also include an impact modifier. Generally, the impact modifier includes an olefin copolymer that is "epoxy-functionalized" in that it contains on average two or more epoxy functional groups per molecule. The impact modifier generally contains olefin monomer units derived from one or more α-olefins. Examples of such monomers include linear and / or branched α-olefins having, for example, 2 to 20 carbon atoms, usually 2 to 10 carbon atoms. Specific examples include ethylene, propylene, 1-butene; 3-methyl-1-butene; 3,3-dimethyl-1-butene; 1-pentene; 1-pentene having one or more methyl, ethyl, or propyl substituents; 1-hexene having one or more methyl, ethyl, or propyl substituents; 1-heptene having one or more methyl, ethyl, or propyl substituents; 1-octene having one or more methyl, ethyl, or propyl substituents; 1-nonene having one or more methyl, ethyl, or propyl substituents; ethyl-, methyl-, or dimethyl-substituted 1-decene; 1-dodecene; and styrene. Particularly desirable α-olefin monomers are ethylene and propylene. For example, in one embodiment, the α-olefin monomer includes at least ethylene. In another embodiment, the α-olefin monomer includes ethylene and octene.

[0044]

[0046] The impact modifier (or polyolefin copolymer) may also contain epoxy-functional monomer units. One example of such a unit is an epoxy-functional (meth)acrylic monomer component. As used herein, the term "(meth)acrylic" includes acrylic and methacrylic monomers, as well as salts or esters thereof such as acrylate and methacrylate monomers. For example, suitable epoxy-functional (meth)acrylic monomers may include, but are not limited to, those containing a 1,2-epoxy group such as glycidyl acrylate and glycidyl methacrylate. Other suitable epoxy-functional monomers include allyl glycidyl ether, glycidyl ethacrylate, and glycidyl itaconate. Other suitable monomers may also be utilized to facilitate the achievement of the desired molecular weight.

[0045]

[0047] Of course, the impact modifier can also contain other monomer units as is known in the art. For example, another suitable monomer may include a (meth)acrylic monomer that is not epoxy-functional. Examples of such (meth)acrylic monomers include methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, s-butyl acrylate, i-butyl acrylate, t-butyl acrylate, n-amyl acrylate, i-amyl acrylate, isobornyl acrylate, n-hexyl acrylate, 2-ethylbutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, methylcyclohexyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, 2-hydroxyethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, i-propyl methacrylate, i-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, i-amyl methacrylate, s-butyl methacrylate, t-butyl methacrylate, 2-ethylbutyl methacrylate, methylcyclohexyl methacrylate, cinnamyl methacrylate, crotyl methacrylate, cyclohexyl methacrylate, cyclopentyl methacrylate, 2-ethoxyethyl methacrylate, isobornyl methacrylate, and the like, and combinations thereof may also be included.

[0046]

[0048] In one embodiment, the impact modifier may include a copolymer of ethylene and glycidyl methacrylate. In another embodiment, the impact modifier may include a copolymer of ethylene, octene, and glycidyl methacrylate, particularly a copolymer of poly(ethylene-octene) and glycidyl methacrylate. Further, in one embodiment, such a copolymer may be a random copolymer.

[0047]

[0049] In one particular embodiment, the impact modifier may be a copolymer formed from an epoxy-functional (meth)acrylic monomer component, an α-olefin monomer component, and a non-epoxy-functional (meth)acrylic monomer component. The impact modifier may be, for example, poly(ethylene-co-butyl acrylate-co-glycidyl methacrylate).

[0048]

[0050] The relative portions of the monomer components can be selected to achieve a balance between epoxy functionality and melt flow rate. More specifically, a high epoxy monomer content can result in good adhesion to metal, but if the content is overly high, the melt flow rate may be reduced to the extent that the copolymer adversely affects the melt strength of the polymer composition. Thus, in most embodiments, the epoxy-functional (meth)acrylic monomer constitutes about 1 wt.% to about 20 wt.% of the copolymer, about 2 wt.% to about 15 wt.% in some embodiments, and about 3 wt.% to about 10 wt.% in some embodiments. Also, the α-olefin monomer may constitute about 55 wt.% to about 95 wt.% of the copolymer, about 60 wt.% to about 90 wt.% in some embodiments, and about 65 wt.% to about 85 wt.% in some embodiments. When utilized, other monomer components (e.g., non-epoxy-functional (meth)acrylic monomers) may constitute about 5 wt.% to about 35 wt.% of the copolymer, about 8 wt.% to about 30 wt.% in some embodiments, and about 10 wt.% to about 25 wt.% in some embodiments. However, it should be understood that the concentrations of other monomers may also be used in accordance with the present invention. Nevertheless, the resulting melt flow rate is determined in accordance with ASTM-D1238-13 at a load of 2.16 kg and a temperature of 190 °C, typically about 1 to about 30 grams per 10 minutes (“g / 10 min”), about 2 to about 20 g / 10 min in some embodiments, and about 3 to about 15 g / 10 min in some embodiments.

[0049]

[0051] The epoxy-functionalized component may be produced from monomers selected by a copolymerization process, a grafting process, or both in some embodiments. For example, in some embodiments, the epoxy-functional monomer is grafted onto an olefin monomer. As an example, glycidyl methacrylate may be grafted onto an olefin component. These may include glycidyl methacrylate grafted onto polyethylene such as high-density polyethylene to form GMA-g-PE, and glycidyl methacrylate grafted onto polyethylene-octene to form GMA-g-PE.

[0050]

[0052] One example of a suitable epoxy-functionalized copolymer that may be used in the present invention is commercially available from Arkema under the name LOTADER® AX8840. LOTADER® AX8840 has a melt flow rate of, for example, 5 g / 10 minutes and is a random copolymer of ethylene and glycidyl methacrylate (monomer content 8 wt.%). Another suitable copolymer is commercially available from Arkema under the name LOTADER® AX8900, which is a terpolymer of ethylene, acrylate ester, and glycidyl methacrylate, and has a melt flow rate of 6 g / 10 minutes and a monomer content of 8 wt.% glycidyl methacrylate. Another suitable copolymer is commercially available from DuPont under the name ELVALOY® PTW, which is a terpolymer of ethylene, butyl acrylate, and glycidyl methacrylate, and has a melt flow rate of 12 g / 10 minutes and a content of 4 wt.% to 5 wt.% glycidyl methacrylate monomer.

[0051]

[0053] It should be understood that additional impact modifiers may also be utilized in the polymer composition if so desired. Examples of such impact modifiers may include, for example, polyurethane, polybutadiene, acrylonitrile-butadiene-styrene, polyamide, block copolymers (e.g., polyether-polyamide block copolymers), etc., and mixtures thereof.

[0052]

[0054] The impact modifier may be present in an amount of about 0.1 wt.% or more of the polymer composition, in some embodiments about 0.5 wt.% or more, in some embodiments about 1 wt.% to about 40 wt.%, in some embodiments about 2 wt.% to about 30 wt.%, and in some embodiments about 3 wt.% to about 20 wt.%.

[0053] C. Fibrous filler

[0055] In order to improve the thermal and mechanical properties of the polymer composition without significantly affecting its electrical properties, fibrous fillers may also be utilized in the polymer composition. Fibrous fillers typically include fillers having a high tensile strength relative to their mass. For example, the maximum tensile strength of the fibers (determined according to ASTM D2101) is typically about 1,000 to about 15,000 megapascals ("MPa"), in some embodiments about 2,000 MPa to about 10,000 MPa, and in some embodiments about 3,000 MPa to about 6,000 MPa. To promote the maintenance of the desired dielectric properties, such high-strength fibers are generally made of materials of insulating nature, such as glass, ceramic or mineral (e.g., alumina or silica), aramid (e.g., Kevlar® sold by E.I. duPont de Nemours, Wilmington, Delaware), mineral, polyolefin, polyester, etc.

[0054]

[0056] In one embodiment, the fibrous filler may include glass fiber, mineral fiber, or a mixture thereof. For example, in one embodiment, the fibrous filler may include glass fiber. Particularly suitable glass fibers may include E-glass, A-glass, C-glass, D-glass, AR-glass, R-glass, S1-glass, S2-glass, and the like. In another embodiment, the fibrous filler may include mineral fiber. Examples of the mineral fiber include silicates such as nesosilicates, 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 anthophyllite, etc.), phyllosilicates (e.g., aluminum phyllosilicates such as palygorskite), tectosilicates, etc.; sulfates such as calcium sulfate (e.g., dehydrated or anhydrous gypsum); those derived from mineral wool (e.g., rock or slag wool), and the like. Inosilicates such as wollastonite fiber available from Nyco Minerals under the trade name NYGLOS® (e.g., NYGLOS® 4W or NYGLOS® 8) are particularly suitable.

[0055]

[0057] Furthermore, the fibrous filler may have various different sizes, but fibers having a specific aspect ratio may promote the improvement of the mechanical properties of the polymer composition. That is, fibrous fillers having an aspect ratio (average length divided by nominal diameter) of about 2 or more, in some embodiments about 4 or more, in some embodiments about 5 to about 50, and in some embodiments about 8 to about 40 may be particularly beneficial. Such fibrous fillers may have a weight average length of, for example, about 10 micrometers or more, in some embodiments about 25 micrometers or more, in some embodiments about 50 micrometers or more to about 800 micrometers or less, and in some embodiments about 60 micrometers to about 500 micrometers. Also, such fibrous fillers may have a volume average length of, for example, about 10 micrometers or more, in some embodiments about 25 micrometers or more, in some embodiments about 50 micrometers or more to about 800 micrometers or less, and in some embodiments about 60 micrometers to about 500 micrometers.

[0056]

[0058] The fibrous filler may similarly have a nominal diameter of about 5 micrometers or more, in some embodiments about 6 micrometers or more, in some embodiments about 8 micrometers to about 40 micrometers, and in some embodiments about 9 micrometers to about 20 micrometers. The relative amount of the fibrous filler may also be selectively controlled to achieve the desired mechanical and thermal properties without adversely affecting other properties of the polymer composition, such as its fluidity and dielectric properties. In this regard, the fibrous filler may have a relative dielectric constant of about 6 or less, in some embodiments about 5.5 or less, in some embodiments about 1.1 to about 5, and in some embodiments about 2 to about 4.8 at a frequency of 1 GHz.

[0057]

[0059] The fibrous filler may be in a modified or unmodified form, and may be sized or chemically treated, for example, to improve adhesion to plastics. In some examples, sizing may be applied to the glass fibers to protect the glass fibers and not only smooth the fibers but also improve the adhesion between the fibers and the matrix material. When present, the sizing may include silanes, film formers, lubricants, wetting agents, adhesives, optionally antistatic agents and plasticizers, emulsifiers, and optionally additional additives. In one particular embodiment, the sizing may include silanes. Specific examples of silanes are aminosilanes such as 3-trimethoxysilylpropylamine, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(3-trimethoxysilylpropyl)ethane-1,2-diamine, 3-(2-aminoethyl-amino)propyltrimethoxysilane, N-[3-(trimethoxysilyl)propyl]-1,2-ethanediamine.

[0058]

[0060] The fibrous filler may generally have a relatively flat cross-sectional dimension in that it has an aspect ratio (i.e., the cross-sectional width divided by the cross-sectional thickness) of about 1.5 to about 30, in some embodiments about 2 to about 20, in some embodiments about 3 to about 10, and in some embodiments about 3 to about 6. The fibrous filler may have a nominal width of, for example, about 1 to about 50 micrometers, in some embodiments about 5 to about 50 micrometers, and in some embodiments about 10 to about 35 micrometers. Also, the fibrous filler may have a nominal thickness of about 0.5 to about 30 micrometers, in some embodiments about 1 to about 20 micrometers, and in some embodiments about 3 to about 15 micrometers. Further, the fibrous filler may have a narrow size distribution. That is, at least about 60 volume % of the fibrous filler, in some embodiments at least about 70 volume % of the fibrous filler, and in some embodiments at least about 80 volume % of the fibrous filler may have a width and / or thickness within the above ranges. The volume average length of the fibrous filler may be about 10 to about 500 micrometers, in some embodiments about 100 to about 400 micrometers, and in some embodiments about 150 to about 350 micrometers.

[0059]

[0061] The fibrous filler may constitute, for example, about 1 wt.% or more of the polymer composition, in some embodiments about 2 wt.% or more, in some embodiments about 3 wt.% to about 40 wt.%, and in some embodiments about 5 wt.% to about 30 wt.%.

[0060] D. Dielectric filler

[0062] To facilitate achieving the desired dielectric properties, the polymer composition can also contain a dielectric filler. These fillers may be utilized in an amount sufficient to lower the relative permittivity of the polymer as shown above. For example, the dielectric filler can reduce the relative permittivity of the polymer matrix by about 2% or more, in some embodiments about 3% or more, in some embodiments about 3.5% to about 50%, and in some embodiments about 4% to about 30%. Similarly, the dielectric filler can reduce the dielectric tangent of the polymer matrix by about 2% or more, in some embodiments about 3% or more, in some embodiments about 3.5% to about 50%, and in some embodiments about 4% to about 30%. Nevertheless, in one embodiment, these fillers may have a relative permittivity of about 3.0 or less at 100 MHz, in some embodiments about 2.5 or less, in some embodiments about 1.1 to about 2.3, and in some embodiments about 1.2 to about 2.0.

[0061]

[0063] These dielectric fillers may be organic dielectric fillers, inorganic dielectric fillers, or mixtures thereof. In one embodiment, these fillers may include inorganic dielectric fillers. These dielectric fillers may include hollow inorganic fillers, glass flakes, polymer fillers, or mixtures thereof. In one embodiment, the dielectric filler includes a hollow inorganic filler. In another embodiment, the dielectric filler includes glass flakes. In a further embodiment, the dielectric filler includes a polymer filler.

[0062]

[0064] The dielectric filler may constitute, for example, about 1 wt.% or more of the polymer composition, in some embodiments about 4 wt.% or more, in some embodiments about 5 wt.% to about 40 wt.%, and in some embodiments about 10 wt.% to about 30 wt.%.

[0063] i. Hollow inorganic filler

[0065] To facilitate the achievement of desired dielectric properties, the dielectric filler may include a hollow inorganic filler. In particular, the hollow inorganic filler may have a specific size that promotes the improvement of the dielectric properties of the polymer composition. Also, the hollow inorganic filler can be excellent in strength while enabling the polymer composition to have a reduced weight.

[0064]

[0066] Generally, the hollow inorganic filler has an internal hollow space or cavity and may be synthesized using techniques known in the art. The hollow inorganic filler may be made from conventional materials. For example, examples of the hollow inorganic filler may include alumina, silica, zirconia, magnesia, glass, fly ash, borate, phosphate, ceramic, etc. In one embodiment, examples of the hollow inorganic filler may include a hollow glass filler, a hollow ceramic filler, and mixtures thereof. In one embodiment, the hollow inorganic filler includes a hollow glass filler.

[0065]

[0067] The hollow glass filler may be made of soda lime borosilicate glass, soda lime glass, borosilicate glass, sodium borosilicate glass, sodium silicate glass, or aluminosilicate glass. In this regard, in one embodiment, the composition of the glass is not limited but may be at least about 65 wt% SiO2, 3 - 15 wt% Na2O, 8 - 15 wt% CaO, 0.1 - 5 wt% MgO, 0.01 - 3 wt% Al2O3, 0.01 - 1 wt% K2O, and optionally other oxides (e.g., Li2O, Fe2O3, TiO2, B2O3). In another embodiment, the composition may be about 50 - 58 wt% SiO2, 25 - 30 wt% Al2O3, 6 - 10 wt% CaO, 1 - 4 wt% Na2O / K2O, and 1 - 5 wt% other oxides. Further, in one embodiment, the hollow glass filler may contain more alkaline earth metal oxides than alkali metal oxides. For example, the weight ratio of alkaline earth metal oxides to alkali metal oxides may be greater than 1, in some embodiments about 1.1 or more, in some embodiments about 1.2 - about 4, and in some embodiments about 1.5 - about 3. Nevertheless, it should be understood that the composition of the glass may vary depending on the type of glass utilized and still provide the benefits desired by the present invention.

[0066]

[0068] The hollow inorganic filler may have at least one dimension having an average value of about 1 micrometer or more, in some embodiments about 5 micrometers or more, in some embodiments about 8 micrometers or more, in some embodiments about 1 micrometer to about 150 micrometers, in some embodiments about 10 micrometers to about 150 micrometers, and in some embodiments about 12 micrometers to about 50 micrometers. In one embodiment, such an average value may be referred to as the d 50 value.

[0067]

[0069] Furthermore, the hollow inorganic filler has a D of about 1 micrometer or more, in some embodiments about 3 micrometers or more, in some embodiments about 5 micrometers to about 20 micrometers, and in some embodiments about 6 micrometers to about 15 micrometers. 10 It may have a D of about 10 micrometers or more, in some embodiments about 15 micrometers or more, in some embodiments about 20 micrometers to about 150 micrometers, and in some embodiments about 22 micrometers to about 50 micrometers. 90 It may have.

[0068]

[0070] In this regard, the hollow inorganic filler may be present in a size distribution that can be a Gaussian size distribution, a normal size distribution, or a non-normal size distribution. In one embodiment, the hollow inorganic filler may have a Gaussian size distribution. In another embodiment, the hollow inorganic filler may have a normal size distribution. In a further embodiment, the hollow inorganic filler may have a non-normal size distribution. Examples of non-normal size distributions can include unimodal and multimodal (e.g., bimodal) size distributions.

[0069]

[0071] When referring to the above dimensions, such dimensions may be any dimensions. However, in one embodiment, such dimensions refer to the diameter. For example, such values for the dimensions refer to the average diameter of a sphere. Dimensions such as the average diameter may be determined in accordance with 3M QCM 193.0. In this regard, in one embodiment, the hollow inorganic filler may refer to a hollow sphere such as a hollow glass sphere. For example, the hollow inorganic filler may have an average aspect ratio of approximately 1. Generally, the average aspect ratio may be about 0.8 or more, in some embodiments about 0.85 or more, in some embodiments about 0.9 to about 1.3, and in some embodiments about 0.95 to about 1.05.

[0070]

[0072] Furthermore, the hollow inorganic filler may have a relatively thin wall to assist in reducing the dielectric properties and weight of the polymer composition. The wall thickness may be about 50% or less of the average dimension of the hollow inorganic filler, such as the average diameter, about 40% or less in some embodiments, about 1% to about 30% in some embodiments, and about 2% to about 25% in some embodiments.

[0071]

[0073] Furthermore, the hollow inorganic filler may have a specific true density that enables easy handling and provides a polymer composition with reduced weight. Generally, the true density refers to the quotient obtained by dividing the mass of the hollow filler sample by the true volume of the mass of the hollow filler, and the true volume is referred to as the total volume of the hollow filler. In this regard, the true density of the hollow inorganic filler is about 0.1 g / cm 3 or more, about 0.2 g / cm 3 or more in some embodiments, about 0.3 g / cm 3 or more to about 1.2 g / cm 3 in some embodiments, about 0.4 g / cm 3 or more to about 0.9 g / cm 3 and may be. The true density may be determined according to 3M QCM 14.24.1.

[0072]

[0074] The fillers can be hollow and have mechanical strength that allows maintaining the integrity of their structures, and as a result, the fillers are less likely to break during processing and / or use. In this regard, the isostatic pressure resistance (i.e., at least 80 vol.%, such as at least 90 vol.%, of the hollow fillers survive) of the hollow inorganic filler may be about 20 MPa or more, about 100 MPa or more in some embodiments, about 150 MPa to about 500 MPa in some embodiments, and about 200 MPa to about 350 MPa in some embodiments. The isostatic pressure resistance may be determined according to 3M QCM 14.1.8.

[0073]

[0075] The alkalinity of the hollow inorganic filler is about 1.0 meq / g or less, about 0.9 meq / g or less in some embodiments, about 0.1 meq / g to about 0.8 meq / g in some embodiments, and about 0.2 meq / g to about 0.7 meq / g in some embodiments. The alkalinity may be determined according to 3M QCM 55.19. To provide a relatively low alkalinity, the hollow inorganic filler may be treated with a suitable acid such as phosphoric acid.

[0074]

[0076] Furthermore, the hollow inorganic filler may also include a surface treatment to assist in providing better compatibility with the polymer and / or other components in the polymer composition. By way of example, the surface treatment may be silanization. In particular, the surface treatment agent may include, but is not limited to, aminosilane, epoxysilane, and the like.

[0075] ii. Glass flake

[0077] To promote the achievement of desired dielectric properties, the low dielectric constant inorganic filler may include glass flakes. In particular, the glass flakes may have a specific size that promotes the improvement of the dielectric properties of the polymer composition. Also, the glass flakes are excellent in strength, and thereby can impart desired mechanical strength to the polymer composition.

[0076]

[0078] The flakes may have a relatively high aspect ratio (e.g., the average length or diameter divided by the average thickness) of about 4 or more, about 8 or more in some embodiments, about 10 to about 1,500 in some embodiments, about 25 to about 1,000 in some embodiments, and the like. The average thickness may be, for example, about 10 micrometers or less, about 8 micrometers or less in some embodiments, about 0.01 micrometer to about 6 micrometers or less in some embodiments, and about 0.1 micrometer to about 5 micrometers in some embodiments. In this regard, glass flakes are generally distinguished from fibrous fillers by their non-fibrous nature.

[0077] iii. Polymer filler

[0079] To promote the achievement of the desired dielectric properties, the dielectric filler may include a polymer filler. The polymer filler may generally be any polymer having a relatively low dielectric constant. In this regard, the polymer filler may be a polyethylene polymer. As used herein, a polyethylene polymer refers to a polymer made from more than 90% ethylene-derived units, such as more than 95% ethylene-derived units, or 100% ethylene-derived units. Polyethylene may be a homopolymer or a copolymer containing other monomer units.

[0078]

[0080] As described above, in one embodiment, the polyethylene is a homopolymer of ethylene. In another embodiment, the polyethylene may be a copolymer. For example, the polyethylene may be a copolymer of ethylene and another olefin containing 3 to 16 carbon atoms, such as 3 to 10 carbon atoms, such as 3 to 8 carbon atoms. These other olefins include, but are not limited to, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methylpenta-1-ene, 1-decene, 1-dodecene, 1-hexadecene, etc. Also, polyene comonomers such as 1,3-hexadiene, 1,4-hexadiene, cyclopentadiene, dicyclopentadiene, 4-vinylcyclohex-1-ene, 1,5-cyclooctadiene, 5-vinylidene-2-norbornene, and 5-vinyl-2-norbornene are also available herein. However, when present, the amount of non-ethylene monomers in the copolymer may be less than about 10 mol.%, such as less than about 5 mol.%, such as less than about 2.5 mol.%, such as less than about 1 mol.%, where mol.% is based on the total moles of monomers in the polymer.

[0079]

[0081] Furthermore, the polymer composition may be composed of a blend of one or more polyethylene polymers or copolymers and another thermoplastic polymer, such as polypropylene, polybutylene, polymethylpentene, linear low density polyethylene, or a mixture thereof.

[0080]

[0082] In one embodiment, ultra-high molecular weight polyethylene (UHMW-PE) may be utilized, for example, as a powder, particularly as a fine powder. UHMW-PE generally has an average particle diameter D in the range of 1 to 500 μm, in some embodiments 1 to 300 μm, in some embodiments 50 to 200 μm, in some embodiments 100 to 200 μm, and in some embodiments 120 to 180 μm 50 (which is based on volume and determined by light scattering). In one embodiment, the polyethylene may be a free-flowing powder. The particle size of the powder may be measured using a laser diffraction method in accordance with ISO13320. In one embodiment, 90% of the polyethylene may have a particle size of less than about 250 micrometers. In other embodiments, 90% of the polyethylene may have a particle size of less than about 200 micrometers.

[0081]

[0083] The molecular weight of the polyethylene polymer may vary depending on the particular application. For example, the polyethylene used to produce the particles may include high molecular weight polyethylene, very high molecular weight polyethylene, and / or ultra-high molecular weight polyethylene. "High molecular weight polyethylene" refers to a polyethylene composition having a weight average molecular weight of at least about 3×10 5 g / mol, and is intended to include very high molecular weight polyethylene and ultra-high molecular weight polyethylene as used herein. For the purposes of this specification, the molecular weights referred to herein are determined according to the Margolies equation ("Margolies molecular weight"). "Very high molecular weight polyethylene" refers to a polyethylene composition having a weight average molecular weight of less than about 3×10 6 g / mol and higher than about 1×10 6 g / mol. In some embodiments, the molecular weight of the very high molecular weight polyethylene composition is from about 2×10 6 g / mol to less than about 3×10 6 g / mol. "Ultra-high molecular weight polyethylene" refers to a polyethylene composition having a weight average molecular weight of at least about 3×10 6 g / mol. In some embodiments, the molecular weight of the ultra-high molecular weight polyethylene composition is about 3×106 g / mol to approximately 30×10 6 g / mol, or approximately 3×10 6 g / mol to approximately 20×10 6 g / mol, or approximately 3×10 6 g / mol to approximately 10×10 6 g / mol, or approximately 3×10 6 g / mol to approximately 6×10 6 g / mol.

[0082]

[0084] For example, the polyethylene polymer may have an average molecular weight determined according to the Margolies equation. The molecular weight may first be determined by measuring the viscosity number according to DIN EN ISO test 1628. The dry powder flow is measured using a 25 mm nozzle. Next, using the Margolies equation, a molecular weight of at least about 500,000 g / mol or greater, in some embodiments greater than about 1,000,000 g / mol, in some embodiments from about 1,500,000 g / mol to about 12,000,000 g / mol, and in some embodiments from about 2,000,000 g / mol to about 10,000,000 g / mol is calculated from the viscosity number. Nevertheless, the molecular weight of the polyethylene may be adjusted by adding hydrogen during synthesis. Also, the temperature and / or the type and concentration of the cocatalyst may be varied to finely adjust the molecular weight.

[0083]

[0085] In one embodiment, the polyethylene may have a unimodal molecular weight distribution. Alternatively, the polyethylene may exhibit a bimodal molecular weight distribution. For example, a bimodal distribution generally refers to a polymer having distinct higher and distinct lower molecular weights (e.g., two distinct peaks) on a size exclusion chromatography or gel permeation chromatography curve. In another embodiment, the polyethylene may exhibit more than two molecular weight distribution peaks such that it has a multimodal (e.g., trimodal, tetramodal, etc.) distribution. Alternatively, when the polyethylene is composed of a blend of higher and lower molecular weight components, it may exhibit a broad molecular weight distribution such that the size exclusion chromatography or gel permeation chromatography curve does not show at least two distinct peaks, but instead shows one distinct peak that is broader than the individual component peaks.

[0084]

[0086] In one embodiment, the polymer composition may be composed of more than one polyethylene each having a different molecular weight and / or molecular weight distribution. For example, the molecular weight distribution may be within the defined range of the average molecular weight shown above.

[0085]

[0087] In addition to the molecular weight, the polyethylene may also have a specific density. In this regard, in one embodiment, the polyethylene may be high density polyethylene. Generally, high density polyethylene has a density of about 0.93 g / cm 3 or more, and in some embodiments about 0.93 g / cm 3 to about 0.97 g / cm 3 .

[0086]

[0088] Polyethylene may have an intrinsic viscosity, determined according to ISO 1628 part 3, using its concentration in decahydronaphthalene of 0.0002 g / mL, of at least 100 mL / g, in some embodiments at least 500 mL / g, in some embodiments from about 1,500 mL / g to about 6,000 mL / g, and in some embodiments from about 2,000 mL / g to about 5,000 mL / g. Polyethylene may have a melt flow rate, determined according to ISO test 1133, of less than 1 g / 10 minutes, in some embodiments less than 1 g / 10 minutes, in some embodiments less than about 0.5 g / 10 minutes, in some embodiments less than about 0.1 g / 10 minutes, and generally higher than 0.001 g / 10 minutes, as determined at 190 °C and a load of 21.6 kg.

[0087]

[0089] Furthermore, the polyethylene may have a specific crystallinity. For example, the crystallinity may be 40% or more, in some embodiments about 45% or more, in some embodiments from about 50% to about 90%, and in some embodiments from about 50% to about 80%.

[0088] E. Epoxy resin

[0090] The polymer composition may also contain an epoxy resin. The epoxy resin may have a specific epoxy equivalent that is particularly effective for use in the present invention. That is, the epoxy equivalent is generally about 250 to about 1,500 grams per equivalent, about 400 to about 1,000 grams in some embodiments, and about 500 to about 800 grams in some embodiments, as determined according to ASTM D1652-11e1. The epoxy resin also typically contains at least about 1.3, about 1.6 to about 8, and about 3 to about 5 epoxide groups per molecule on average. The epoxy resin typically has a relatively low dynamic viscosity of about 1 centipoise to about 25 centipoises, about 2 centipoises to about 20 centipoises in some embodiments, and about 5 centipoises to about 15 centipoises in some embodiments, as determined at a temperature of 25 °C according to ASTM D445-15. At room temperature (25 °C), the epoxy resin is also typically a solid or semi-solid material having a melting point of about 50 °C to about 120 °C, about 60 °C to about 110 °C in some embodiments, and about 70 °C to about 100 °C in some embodiments.

[0089]

[0091] The epoxy resin may be saturated or unsaturated, linear or branched, aliphatic, alicyclic, aromatic, or heterocyclic, and may have substituents that do not substantially interfere with the reaction with oxirane. Suitable epoxy resins include, for example, glycidyl ethers (e.g., diglycidyl ethers) prepared by reacting a hydroxyl compound containing at least 1.5 aromatic hydroxyl groups with epichlorohydrin, optionally under alkaline reaction conditions. Dihydroxyl compounds are particularly suitable. For example, the epoxy resin may be a diglycidyl ether of a dihydric phenol, a diglycidyl ether of a hydrogenated dihydric phenol, etc. The diglycidyl ether of a dihydric phenol can be formed, for example, by reacting an epihalohydrin with a dihydric phenol. Examples of suitable dihydric phenols include, for example, 2,2-bis(4-hydroxyphenyl)propane (“bisphenol A”); 2,2-bis-4-hydroxy-3-tert-butylphenyl)propane; 1,1-bis(4-hydroxyphenyl)ethane; 1,1-bis(4-hydroxyphenyl)isobutane; bis(2-hydroxy-1-naphthyl)methane; 1,5-dihydroxynaphthalene; 1,1-bis(4-hydroxy-3-alkylphenyl)ethane, etc. Suitable dihydric phenols can also be obtained from the reaction of phenol with aldehydes such as formaldehyde (“bisphenol F”). Commercial examples of such epoxy resins may include EPON™ resins available from Hexion, inc. under the names 862, 828, 826, 825, 1001, 1002, 1009, SU3, 154, 1031, 1050, 133, and 165.

[0090]

[0092] The epoxy resin may constitute, for example, about 0.01 wt.% to about 3 wt.% of the polymer composition, in some embodiments about 0.05 wt.% to about 2 wt.%, and in some embodiments about 0.1 to about 1 wt.%.

[0091] F. Other additives

[0093] A variety of additional additives such as lubricants, heat conductive fillers, pigments, antioxidants, stabilizers, surfactants, waxes, flame retardants, anti-drip additives, nucleating agents (e.g., boron nitride), flow modifiers, coupling agents, antibacterial agents, pigments or other colorants, impact modifiers, and other materials added to improve properties and processability may be included in the polymer composition. Such optional materials may be utilized in the polymer composition in conventional amounts and according to conventional processing techniques. When utilized, for example, such additives typically constitute from about 0.05 wt.% to about 5 wt.% of the polymer composition, and in some embodiments from about 0.1 wt.% to about 1 wt.%.

[0092]

[0094] In one embodiment, the polymer composition may include an antioxidant. In particular, the antioxidant may be a sterically hindered phenolic antioxidant. Examples of such phenolic antioxidants are, for example, calcium bis(ethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate) (Irganox® 1425), terephthalic acid, 1,4,-dithio-, S,S-bis-(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) ester (Cyanox® 1729), triethylene glycol bis(3-tert-butyl-4-hydroxy-5-methylhydrocinnamate), hexamethylene bis(3,5,di-tert-butyl-4-hydroxyhydrocinnamate (Irganox® 259), 1,2-bis(3,5,di-tert-butyl-4-hydroxyhydrocinnamoyl) hydrazide (Irganox® 1024), 4,4’-di-tert-octyldiphenylamine (Naugalube® 438R), phosphonic acid, (3,5-di-tert-butyl-4-hydroxybenzyl)-, dioctadecyl ester (Irganox® 1093), 1,3,5-trimethyl-2,4,6-tris(3’,5’-di-tert-butyl-4’-hydroxybenzyl) benzene (Irganox® 1330), 2,4-bis(octylthio)-6-(4-hydroxy-3,5-di-tert-butylanilino)-1,3,5-triazine (Irganox® 565), isooctyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (Irganox® 1135), octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (Irganox® 1076), 3,7-bis(1,1,3,3-tetramethylbutyl)-10H-phenothiazine (Irganox® LO3), 2,2'-Methylenebis(4-methyl-6-tert-butylphenol) monoacrylate (Irganox® 3052), 2-tert-butyl-6-[1-(3-tert-butyl-2-hydroxy-5-methylphenyl)ethyl]-4-methylphenyl acrylate (Sumilizer® TM4039), 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate (Sumilizer® GS), 1,3-dihydro-2H-benzimidazole (Sumilizer® MB), 2-methyl-4,6-bis[(octylthio)methyl]phenol (Irganox® 1520), N,N'-trimethylenebis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide (Irganox® 1019), 4-n-octadecyloxy-2,6-diphenylphenol (Irganox® 1063), 2,2'-ethylidenebis[4,6-di-tert-butylphenol] (Irganox® 129), NN'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyhydrocinnamide (Irganox® 1098), diethyl (3,5-di-tert-butyl-4-hydroxybenzyl)phosphonate (Irganox® 1222), 4,4'-di-tert-octyldiphenylamine (Irganox® 5057), N-phenyl-1-naphthylamine (Irganox® L05), tris[2-tert-butyl-4-(3-tert-butyl-4-hydroxy-6-methylphenylthio)-5-methylphenyl] phosphite (Hostanox® OSP1), zinc dinonyldithiocarbamate (Hostanox® VP-ZNCS 1), 3,9-bis[1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (Sumilizer® AG80), pentaerythrityl tetrakis[3-(3,5-Di-tert-butyl-4-hydroxyphenyl)propionate (Irganox® 1010), ethylene-bis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-toluyl)-propionate (Irganox® 245), 3,5-di-tert-butyl-4-hydroxytoluene (Lowinox BHT, Chemtura), etc. are included. In one embodiment, for example, the antioxidant comprises pentaerythrityl tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, pentaerythritol tetrakis(B-laurylthiopropionate), or a mixture thereof. Some examples of sterically hindered phenolic antioxidants suitable for use in the compositions of the present invention are triazine antioxidants. Commercially available examples of such triazine-based antioxidants are available from American Cyanamid under the name Cyanox® 1790 (where each R group is represented by formula III), and from Ciba Specialty Chemicals under the names Irganox® 3114 (where each R group is represented by formula I), and Irganox® 3125 (where each R group is represented by formula II).

[0093]

[0095] The sterically hindered phenolic antioxidant may constitute from about 0.01 wt.% to about 3 wt.%, in some embodiments from about 0.05 wt.% to about 1 wt.%, and in some embodiments from about 0.05 wt.% to about 0.1 wt.% of the total polymer composition.

[0094]

[0096] In one embodiment, the polymer composition may include a black pigment. The black pigment generally includes a plurality of carbon black particles, such as furnace black, channel black, acetylene black, lamp black, etc. The carbon black particles may have any desired shape, such as granular, flaky (scaly), etc. The average size (e.g., diameter) of the particles may be in the range of, for example, about 1 to about 200 nanometers, in some embodiments about 5 to about 150 nanometers, and in some embodiments about 10 to about 100 nanometers. Also, the carbon black particles are typically desired to be relatively pure, such as containing polycyclic aromatic hydrocarbons (e.g., benzo[a]pyrene, naphthalene, etc.) in an amount of about 1 part per million (「ppm」) or less, and in some embodiments about 0.5 ppm or less. For example, the black pigment may contain benzo[a]pyrene in an amount of about 10 parts per billion (「ppb」) or less, and in some embodiments about 5 ppb or less.

[0095]

[0097] If desired, the black pigment may include a carrier resin that can encapsulate the carbon black particles, thereby providing various benefits. For example, the carrier resin can improve the ability of the particles to be handled and incorporated into the base polymer composition. Any known carrier resin may be used for this purpose, but in certain embodiments, the carrier resin may be the same as the polymer used in the polymer matrix of the polymer composition. If desired, the carrier resin may be pre-blended with the carbon black particles to form a pigment masterbatch, which may then be combined with the polymer. When used, the carrier resin typically constitutes about 50 wt.% to about 95 wt.% of the masterbatch, in some embodiments about 60 wt.% to about 90 wt.%, and in some embodiments about 70 wt.% to about 85 wt.%, and the carbon black particles typically constitute about 5 wt.% to about 50 wt.% of the masterbatch, in some embodiments about 10 wt.% to about 40 wt.%, and in some embodiments about 15 wt.% to about 30 wt.%. Of course, other components may also be incorporated into the masterbatch.

[0096] II. Melt processing

[0098] The method by which the polymer and other optional additives are combined may vary as is known in the art. For example, the materials may be fed simultaneously or sequentially into a melt processing device that dispersively blends the materials. Batch and / or continuous melt processing techniques may be utilized. For example, mixers / kneaders, Banbury mixers, Farrel continuous mixers, single-screw extruders, twin-screw extruders, roll mills, etc. may be used to blend and melt process the materials. One particular suitable melt processing device is a co-rotating twin-screw extruder (e.g., Leistritz co-rotating fully intermeshing twin-screw extruder). Such extruders include feed ports and vent ports and can provide high-intensity distributive and dispersive mixing. For example, the components can be fed into the same or different feed ports of the twin-screw extruder and melt blended to form a substantially homogeneous melt mixture. The melt blending may be carried out under high shear / pressure and heat to ensure sufficient dispersion. For example, the melt processing may be carried out at a temperature of about 50 °C to about 500 °C, and in some embodiments, about 100 °C to about 250 °C. Similarly, the apparent shear rate during melt processing may be in the range of about 100 seconds -1 to about 10,000 seconds -1 , and in some embodiments, about 500 seconds -1 to about 1,500 seconds -1 . Of course, other variable factors such as the residence time during melt processing, which is inversely proportional to the throughput rate, can also be controlled to achieve the desired degree of homogeneity.

[0097]

[0099] If desired, one or more distributive and / or dispersive mixing elements may be utilized within the mixing section of the melt processing apparatus. Suitable distributive mixers may include, for example, Saxon, Dulmage, Cavity Transfer mixers, etc. Similarly, suitable dispersive mixers may include, for example, Blister Ring, Leroy / Maddock, CRD mixers, etc. As is well known in the art, mixing may be further enhanced by using pins in the barrel that cause folding and reorientation of the polymer melt, such as those used in Buss Kneader extruders, Cavity Transfer mixers, and Vortex Intermeshing Pin mixers. The screw speed can also be controlled to improve the characteristics of the composition. For example, in one embodiment, the screw speed may be about 400 rpm or less, such as about 200 rpm to about 350 rpm, or about 225 rpm to about 325 rpm. In one embodiment, the compounding conditions can be adjusted to obtain a polymer composition exhibiting improved impact and tensile properties. For example, the compounding conditions can include the design of the screw to obtain low, medium, or intense screw conditions. For example, the system may have a low to intense screw design where the screw has a single melt section in the downstream half of the screw for gentle melting and distributive melt homogenization purposes. A medium to intense screw design may have a more powerful melt section focused by stronger dispersive elements upstream of the filler feed barrel to achieve uniform melting. Further, this design may have another gentle mixing section downstream for mixing the filler. This section can further increase the shear strength of the screw, although to a lesser degree, and make it more powerful overall than a low to intense design. A highly intense screw design can have the most powerful shear strength of the three. The main melt section may be composed of a long array of highly dispersive kneading blocks. The downstream mixing section can utilize a combination of distributive elements and strong dispersive elements to achieve uniform dispersion of all types of fillers.The shear strength of the highly aggressive screw design may be significantly higher than the other two designs. In one embodiment, the system can include a screw design from moderate to aggressive having a relatively low screw speed (e.g., about 200 rpm to about 300 rpm).

[0098]

[0100] Regardless of the method of combination, the polymer composition may have a relatively low melt viscosity, thereby being able to flow easily during production or molding. For example, the composition has a shear rate of 1,200 seconds at a temperature 20 °C higher than the melt temperature of the polymer -1 and may have a melt viscosity of about 700 Pa·s or less, in some embodiments about 500 Pa·s or less, in some embodiments about 250 Pa·s or less, in some embodiments about 200 Pa·s or less, in some embodiments about 5 to about 150 Pa·s, in some embodiments about 5 to about 100 Pa·s, in some embodiments about 10 to about 100 Pa·s. The melt viscosity may be determined according to 11443:2005. In particular, these melt properties can enable the composition to be easily molded into parts with small dimensions.

[0099]

[0101] Due to the relatively low melt viscosity achievable with the present invention, relatively high molecular weight polymers can also be fed into the extruder with some difficulty. For example, such high molecular weight polymers can have a number average molecular weight of about 14,000 grams per mole ("g / mol") or more, in some embodiments about 15,000 g / mol or more, and in some embodiments from about 16,000 g / mol to about 60,000 g / mol, as determined using gel permeation chromatography as described below, and a weight average molecular weight of about 35,000 g / mol or more, in some embodiments about 50,000 g / mol or more, and in some embodiments from about 60,000 g / mol to about 90,000 g / mol. One benefit of using such high molecular weight polymers such as polyarylene sulfide is that they may generally have a low chlorine content. In this regard, the resulting polymer composition can have a low chlorine content of about 1,200 ppm or less, in some embodiments about 1,000 ppm or less, in some embodiments from 0 to about 900 ppm, and in some embodiments from about 1 to about 600 ppm, etc.

[0100]

[0102] Furthermore, the melt temperature of the polymer composition can be, for example, about 180°C or higher, in some embodiments about 200°C, in some embodiments from about 210°C to about 400°C, and in some embodiments from about 220°C to about 380°C. Even at such melt temperatures, the ratio of the heat deflection temperature ("DTUL"), which is a measure of short-term heat resistance, to the melt temperature can still remain relatively high. For example, the ratio can be in the range of about 0.5 to about 1.00, in some embodiments about 0.6 to about 0.95, and in some embodiments about 0.65 to about 0.85. Specific DTUL values can be, for example, about 200°C or higher, in some embodiments from about 200°C to about 350°C, in some embodiments from about 210°C to about 320°C, and in some embodiments from about 230°C to about 290°C. Such high DTUL values can, in particular, enable the use of a fast and reliable surface mounting process for fitting the structure with other components of the electrical components.

[0101]

[0103] The resulting composition (and molded parts formed therefrom) has also been found to have excellent mechanical properties. For example, the inventors have discovered that the impact strength of the parts may be significantly improved, which is useful when forming small parts. The parts are measured, for example, at 23 °C according to ISO test No. 179-1:2010 (technically equivalent to ASTM D256-12, method B) and are about 3 kJ / m 2 or more, and in some embodiments about 5 kJ / m 2 or more, and in some embodiments about 7 kJ / m 2 or more, and in some embodiments about 8 to about 40 kJ / m 2 and in some embodiments about 9 to about 20 kJ / m 2It may have notched Charpy impact strength. Despite having a low melt viscosity and high impact strength, the inventors have also discovered that it does not have an adverse effect on tensile and flexural mechanical properties. For example, the molded part may have a tensile strength of about 20 to about 500 MPa, in some embodiments about 50 to about 300 MPa, in some embodiments about 50 to about 150 MPa, in some embodiments about 75 to about 125 MPa; a tensile break strain of about 0.5% or more, in some embodiments about 0.6% to about 10%, in some embodiments about 1% to about 5%, in some embodiments about 2% to about 4%; and / or a tensile modulus of about 3,000 MPa to about 30,000 MPa, in some embodiments about 4,000 MPa to about 20,000 MPa, in some embodiments about 4,000 MPa to about 10,000 MPa, in some embodiments about 4,500 MPa to about 7,500 MPa. The tensile properties may be determined according to ISO test No. 527:2012 at 23 °C (technically equivalent to ASTM D638-14). The part may further have a flexural strength of about 20 to about 500 MPa, in some embodiments about 50 to about 300 MPa, in some embodiments about 70 to about 250 MPa, in some embodiments about 100 MPa to about 200 MPa; a flexural break strain of about 0.5% or more, in some embodiments about 0.6% to about 10%, in some embodiments about 1% to about 5%, in some embodiments about 2% to about 4%; and / or a flexural modulus of about 3,000 MPa to about 30,000 MPa, in some embodiments about 4,000 MPa to about 20,000 MPa, in some embodiments about 4,000 MPa to about 10,000 MPa, in some embodiments about 4,500 MPa to about 7,500 MPa. The flexural properties may be determined according to ISO test No. 178:2010 at 23 °C (technically equivalent to ASTM D790-10).

[0102]

[0104] Also, the polymer composition can have a relatively low density. For example, the density is about 2.5 g / cm 3 or less, in some embodiments about 0.1 g / cm 3 to about 2 g / cm 3 , in some embodiments about 0.5 g / cm 3 to about 1.6 g / cm 3It may be. The density may be determined in accordance with ISO1183.

[0103] III. Antenna cover

[0105] As shown in this specification, the polymer composition can be used for an antenna cover. For example, one application is an antenna cover including a window containing the polymer composition defined in this specification, and the antenna cover may be a radio frequency transmitting material. The antenna cover may be fabricated using various suitable manufacturing or molding techniques. Various molding techniques such as injection molding, compression molding, nano molding, overmolding, etc. can be utilized. Regardless of the molding technique used, it has been found that the polymer composition of the present invention, which can have a unique combination of high fluidity and good mechanical properties, is particularly suitable for thin molded parts. For example, the part may have a thickness of about 100 millimeters or less, in some embodiments about 50 millimeters or less, in some embodiments about 100 micrometers to about 10 millimeters, and in some embodiments about 200 micrometers to about 1 millimeter.

[0104]

[0106] In one particular embodiment, nano molding can be utilized to form a layer formed from the polymer composition with or integrated with a first layer such as a metal layer or a conductive layer. For example, nano molding can be used to deposit the polymer composition onto the first layer to form the window of the antenna cover over the metal shield layer and / or the frame. In some embodiments, the first layer can contain any of various different metals, such as aluminum, stainless steel, magnesium, nickel, chromium, copper, titanium, and alloys thereof. In one particular embodiment, the first layer may contain aluminum and / or an aluminum alloy, particularly aluminum.

[0105]

[0107] Due to its inherent properties, the polymer composition can adhere to the first layer. To improve adhesion, the first layer can optionally be pretreated, for example, before nano - molding, to increase the degree of surface indentation and surface area. For example, nano - molding may include a process that forms nano - scale features (e.g., pits, cracks, etc.) and achieves a specific surface roughness on a metal or conductive surface or layer that can act as a shielding layer. This can be achieved using mechanical surface treatments (e.g., sandblasting, polishing, flaring, punching, molding, etc.) and / or chemical surface treatments (e.g., etching, anodization, etc.). For example, techniques for anodically oxidizing a metal surface are described in more detail in U.S. Patent No. 7,989,079 to Lee, et al. Nevertheless, the resulting surface roughness is not necessarily limited by the present invention. However, the resulting surface roughness may be about 0.1 nm or more, for example, about 3 nm or more, for example, about 10 nm or more. For example, the surface roughness may range from about 1 nm to about 500 nm, in some embodiments from about 5 nm to about 300 nm, in some embodiments from about 10 nm to about 200 nm, and in some embodiments from about 20 nm to about 100 nm.

[0106]

[0108] When pre-treated, such a process can also remove unwanted contaminants such as oxide layers, corrosion, oil, etc. The second pre-treatment step may optionally include rinsing the layer with an organic solvent, water, etc. Exemplary organic solvents include acetone, methanol, ethanol, and benzene. As an example of the pre-treatment process, the first etching step may include immersing a first layer, such as a first conductive layer, in a basic aqueous solution (pH>7) to finely etch the surface. Examples of the etching solution may include alkali metal hydroxides such as sodium hydroxide (NaOH), potassium hydroxide (KOH), and soda ash (Na2CO3). Alkaline earth metal hydroxides such as Ca, Sr, Ba, and Ra can also be used, and an alkali with a concentration of 0.1-10% can be used. The first layer may be immersed in the etching solution for several minutes and then rinsed (e.g., in water). The desired surface roughness may be achieved at this stage. A further acid treatment step may include immersing the layer in an acidic aqueous solution and rinsing with water. This step can neutralize the etching solution from the previous step.

[0107]

[0109] In addition to the surface pre-treatment, the first layer can also be pre-heated at a temperature close to but below the melting temperature of the polymer composition. This can be achieved using various techniques such as contact heating, radiant gas heating, infrared heating, convection or forced convection air heating, induction heating, microwave heating, or combinations thereof.

[0108]

[0110] In any case, the polymer composition is generally injected into a mold containing an optionally preheated first layer to form a "window" for the antenna cover. When formed into the desired shape, a composite including a first layer such as a metal layer or a conductive layer and a second layer formed from the polymer composition is cooled so that the second layer formed from the polymer composition is securely adhered to the first layer. The ability to maintain adhesion to the first layer of the polymer composition may be characterized by a bond strength that can be about 5 MPa or more, in some embodiments about 10 MPa or more, in some embodiments about 15 MPa or more, in some embodiments about 10 to about 80 MPa, in some embodiments about 10 to about 50 MPa, in some embodiments about 10 to about 35 MPa, and in some embodiments about 15 to about 30 MPa.

[0109]

[0111] The antenna covers disclosed herein may be particularly useful for 5G applications. As used herein, "5G" generally refers to high-speed data communication by radio frequency signals. 5G networks and systems can communicate data much faster than previous-generation data communication standards (e.g., "4G", "LTE"). Various standards and specifications for quantifying the requirements of 5G communication have been published. As an example, the International Telecommunications Union (ITU) published the International Mobile Telecommunications-2020 ("IMT-2020") standard in 2015. The IMT-2020 standard defines various data transmission criteria for 5G (e.g., downlink and uplink data rates, latency, etc.). The IMT-2020 standard defines the 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 / second and the uplink peak data rate at 10 Gbit / second.

[0110]

[0112] As another example, 3 rdThe Generation Partnership Project (3GPP) recently released a new standard for 5G called "5G NR". 3GPP issued "Release 15" in 2018, which defines "Phase 1" as the standardization of 5G NR. 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. However, as used herein, "5G frequency" may refer to systems that utilize frequencies greater than 60 GHz, for example, up to 80 GHz, up to 150 GHz, and up to 300 GHz. As used herein, "5G frequency" may refer to frequencies of about 2.5 GHz or higher, in some embodiments about 3.0 GHz or higher, in some embodiments about 3 GHz to about 300 GHz or higher, in some embodiments about 4 GHz to about 80 GHz, in some embodiments about 5 GHz to about 80 GHz, in some embodiments about 20 GHz to about 80 GHz, and in some embodiments about 28 GHz to about 60 GHz.

[0111]

[0113] The antenna covers described herein can be used in antenna elements / arrays and systems that meet or can be considered "5G" based on standards published by 3GPP such as Release 15 (2018) and / or IMT - 2020 standards. To achieve such high - speed data communication at high frequencies, antenna elements and arrays generally utilize small feature sizes / spacings (e.g., fine - pitch technology) and / or advanced materials that can improve antenna performance. For example, the feature sizes (spacing between antenna elements, width of antenna elements, etc.) generally depend on the wavelength ("λ") of the desired transmitted and / or received radio frequency that propagates through the dielectric of the substrate on which the antenna elements are formed (e.g., nλ / 4, where n is an integer). Additionally, beamforming and / or beam steering can be utilized to facilitate transmission and reception over multiple frequency ranges or channels (e.g., MIMO, massive MIMO).

[0112]

[0114] As shown, the antenna cover can be particularly useful in 5G radio frequency systems. The 5G radio frequency system may include a base station, a repeater (e.g., a "femtocell"), a relay station, a terminal, a user device, and / or other suitable components. Referring to FIG. 1, the 5G antenna system 100 may include 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., a "femtocell"), and / or other suitable antenna components of the 5G antenna system 100. The relay station 104 may be configured to facilitate communication between the base station 102 and the user computing device 106 and / or other relay stations 104 by relaying or "repeating" signals between the base station 102 and the user computing device 106 and / or between the relay stations 104. The base station 102 may include a MIMO antenna array 110 configured to receive and / or transmit radio frequency signals 112 with the relay station 104, the Wi-Fi repeater 108, and / or directly with the user computing device 106. The user computing device 306 is not necessarily limited by the present invention and includes devices such as 5G smartphones.

[0113]

[0115] The MIMO antenna array 110 may utilize beam steering to focus or direct the radio frequency signal 112 towards the relay station 104. For example, the MIMO antenna array 110 may be configured to adjust the elevation angle 114 with respect to the heading angle 116 defined in the X-Y plane and / or the Z-Y plane, as well as with respect to the Z direction.

[0114]

[0116] Similarly, one or more of the relay station 104, the user computing device 106, and the Wi-Fi repeater 108 may utilize beam steering to directionally tune the sensitivity and / or transmission power of the devices 104, 106, 108 with respect to 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 each device), thereby improving the reception and / or transmission capabilities with respect to the MIMO antenna array 110.

[0115]

[0117] Figures 2A and 2B are, respectively, a top view and a side view 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 each antenna array). Referring to Figure 2A, the antenna elements 200, 202 may be configured to perform beam steering (indicated by arrows 204, 206 and corresponding to the relative azimuth angle) in the X-Y plane. Referring to Figure 2B, the antenna elements 200, 202 may be configured to perform beam steering (indicated by arrows 204, 206 and relatively coinciding) in the Z-Y plane.

[0116]

[0118] Figure 3 is a side view of an antenna cover 320 including a first layer 300, such as a conductive layer, that provides shielding to electronic components formed on a substrate 306. The first layer 300 may be or may include various suitable materials such as various metals or conductive polymer materials. Exemplary metals include aluminum, gold, nickel, tin, copper, and alloys thereof.

[0117]

[0119] The antenna cover 320 may include a second layer 303 formed from a polymer composition as defined herein on a first layer 300. The first layer 300 may define one or more openings 301 such that the second layer 303 is formed over (or partially received within) the opening 301 in the first layer 300 to form a “window” 302 (e.g., illustrated as portions of the second layer 303 connected by dashed lines). In some embodiments, when depositing the second layer 303 on the first layer 300, the second layer 303 may be deposited partially or completely within the opening 301. In other embodiments, depending on the process used to deposit and / or form the second layer 303, the second layer 303 may be formed over the opening 301 without being received within the opening and may “bridge” the opening 301.

[0118]

[0120] The window 302 may be at least partially aligned with one or more antenna elements 304 formed on the substrate 306 such that radio frequency signals can be transmitted and / or received through the “window” 302 of the antenna cover 300. For example, the antenna element 304 may be completely contained within the footprint of the window 302. As another example, the antenna element 304 may be only partially contained within the footprint of the window 302. The polymer composition may be any suitable composition described herein.

[0119]

[0121] One or more additional electronic components 308 (e.g., a front end module, memory, processor, etc.) may be communicatively coupled to one or more of the antenna elements 304. The additional electronic components 308 may be shielded by the first layer 300. For example, such additional electronic components 308 may be attached to the surface of the substrate 306 and may be spaced apart from the window 302 such that the first layer 300 serves to shield the electronic components 308.

[0120]

[0122] In some embodiments, the antenna cover 320 may be disposed relative to the substrate 306 such that the first layer 300 is between the substrate 306 and the second layer 303 (e.g., as illustrated in FIG. 3). One or more insulating layers may be formed between the first layer 300 and the substrate 306 and / or additional electronic components 308, for example, to prevent the first layer 300 from causing a short circuit between the additional components 308.

[0121]

[0123] However, in other embodiments, the antenna cover 320 may be disposed relative to the substrate 306 such that the second layer 303 is between the substrate 306 and the first layer 300.

[0124] Figures 4A through 4C are, respectively, a simplified schematic side view of a base station 400, a first side view of an exemplary MIMO antenna array 402, and a second side view of the MIMO antenna array 402, according to aspects of the present disclosure. The base station 400 of FIG. 4A may generally correspond to the base station 102 of FIG. 1. The base station 400 may include a support structure 404 such as a tower, a building, a parking structure, or other suitable support structure. One or more MIMO antenna arrays 402 may be supported by the support structure 404. The MIMO antenna arrays 402 may be arranged in various suitable configurations (e.g., evenly spaced around a circular outer perimeter, concentrated in a particular direction, etc.).

[0122]

[0125] FIG. 4B is a simplified view of an exemplary MIMO antenna array 402. The MIMO antenna array 402 may include a plurality of antenna elements 406. The MIMO antenna array 402 may be used to provide a massive MIMO function. More particularly, radio frequency interactions between the various elements 406 may be controlled or coordinated to provide a plurality of transmit and / or receive channels. The transmit power and / or receive sensitivity may be directionally controlled to concentrate or direct radio frequency signals, for example, as described with respect to the radio frequency signal 112 of FIG. 1.

[0123]

[0126] As an example, the antenna element 406 may have respective widths "w", lengths "l", and spacing distances "S1" and "S2" therebetween (e.g., in the X and Y directions respectively). These dimensions may be selected to achieve 5G wireless frequency communication at a desired 5G frequency. More specifically, the dimensions may be selected to tune the antenna array 402 to transmit and / or receive data using radio frequency signals within a 5G frequency spectrum (e.g., greater than 3 GHz and / or greater than 28 GHz). The dimensions may be selected based on the material properties of the substrate. For example, one or more of "w", "l", "S1", or "S2" may correspond to a plurality of propagation wavelengths ("λ") of a desired frequency through the substrate material (e.g., nλ / 4, where n is an integer).

[0124]

[0127] As an example, λ may be as follows:

[0125]

Number

[0126] (where c is the speed of light in a vacuum, ε R is the relative permittivity of the substrate (or surrounding material), and f is the desired frequency) may be calculated as follows.

[0127]

[0128] FIG. 4C is a second side view of the MIMO antenna array 402. The antenna element 406 may be attached or coupled to a base or substrate 408. An antenna cover 410 may be formed or positioned on the substrate 408 and / or the antenna element 406. In some embodiments, the antenna cover 410 may include one or more "windows" of a radio frequency transmissive polymer composition that are at least partially aligned with respective antenna elements 406, as described above with reference to FIG. 3. However, in other embodiments, the antenna cover 410 may not have "windows" and may instead include a layer of polymer composition that is not blocked by other materials.

[0128]

[0129] It should be understood that the antenna covers described herein may include any suitable structure for covering, surrounding, protecting, or otherwise providing a physical barrier to one or more antenna elements. As used herein, a "layer" of a polymer composition can generally refer to a thin, planar structure. However, a "layer" may also be formed as an enclosure, housing, etc. Thus, the "layer" of the polymer composition of the antenna cover can have various shapes. For example, the "layer" of the polymer composition of the antenna cover may be shaped (e.g., curved) to form an enclosure or housing for a MIMO antenna array (e.g., in a base station).

[0129] Test method

[0130] Tensile strength, modulus of elasticity, elongation at break: Tensile properties may be tested in accordance with ISO test No. 527:2012 (technically equivalent to ASTM D638-14). Measurements of the modulus of elasticity and strength may be made on the same test specimen sample with a length of 80 mm, a thickness of 10 mm, and a width of 4 mm. The test temperature may be 23 °C, and the test speed may be 1 or 5 mm / min.

[0130]

[0131] Flexural strength, modulus of elasticity, elongation at break: Flexural properties may be tested in accordance with ISO test No. 178:2010 (technically equivalent to ASTM D790-10). This test may be carried out on a support span of 64 mm. The test may be performed at the center of an uncut ISO 3167 multipass bar. The test temperature may be 23 °C, and the test speed may be 2 mm / min.

[0131]

[0132] Notched Charpy Impact Strength: The notched Charpy impact strength may be tested in accordance with ISO 179-1 (technically equivalent to ASTM D256, Method B). This test is performed using a Type A notch (0.25 mm base radius) and a Type 1 specimen size (length 80 mm, width 10 mm, and thickness 4 mm). The specimens are cut from the center of the multi-pass bar using a single-flute milling machine. The test temperature may be 23 °C.

[0132]

[0133] Relative Dielectric Constant (「Dk」) and Dissipation Factor (「Df」): The relative dielectric constant (or relative static dielectric constant) and the dissipation factor are determined using a known split-post dielectric resonance method. The technique utilized is as described in IEC 60250. The samples have a size of 80 mm × 80 mm × 1 mm, and five samples are tested to record the average value.

[0133]

[0134] Adhesion Test: The ability of the molded parts to adhere to the metal components may be determined by testing the tensile shear strength of the samples. The test specimens may be prepared by an injection molding process using a three-plate mold with a specific cavity structure. After embedding a pre-treated aluminum metal insert in the mold, molten plastic is injected into the cavity to adhere to the metal part. Once the plastic has cooled in the mold, the integrated part is removed from the mold. All specimens are conditioned before testing. The injection molding may be performed on a FANUC Roboshot s-2000i 100B. The barrel temperature may be set to ensure that the plastic melting temperature is approximately 320 °C. The mold temperature may be 140 °C, the screw speed may be 50 rpm, the injection speed may be 150 mm / s, and the holding pressure may be 1,000 bar. The test specimens may have a length of 80 mm, a thickness of 10 mm, and a width of 4 mm. The test temperature may be 23 degrees, and the maximum test speed may be 50 mm / min. The test may be performed in accordance with ISO Test No. 19095-2015 using an INSTRON (trademark) 5969 dual-column tensile testing machine. The tensile shear strength is recorded as the maximum force reached before the specimen breaks.

Example

[0134]

[0135] The following examples were conducted to illustrate some of the advantages and benefits of the polymer compositions made in accordance with the present disclosure. Example 1

[0136] Samples containing polybutylene terephthalate were formulated according to Table 1.

[0135]

Table 1

[0136]

[0137] The ultra-high molecular weight polyethylene particles had an average particle size (d 50 ) of 145 micrometers as determined by laser scattering. The average molecular weight of the ultra-high molecular weight polyethylene was 5,700,000 g / mol (Margolies equation). The ultra-high molecular weight polyethylene had a density of 0.930 g / cm 3 and a bulk density of 0.45 g / cm 3 . The ultra-high molecular weight polyethylene had a melt flow rate of less than 0.1 g / 10 min at 190 °C and a load of 21.6 kg and a viscosity number of less than 3,000 ml / g.

[0137]

[0138] A 32 mm twin-screw extruder (Steer) was used with the parameters shown in Table 2. All raw materials except glass fiber were added to the throat feed zone. The glass fiber was added from the middle feed zone. Each sample was taken out in the form of strands from a die having a diameter of 3.2 mm. The obtained samples were granulated after a water cooling step.

[0138]

Table 2

[0139] After pre-drying the granulated product at 120 °C for 4 hours, injection molding was carried out using a Fanuc Roboshot S2000i-100B injection molding machine with the parameters shown in Table 3 to form test specimens from each sample composition.

[0140]

Table 3

[0141]

[0140] Various properties of the test specimens molded from each sample composition were measured and reported in Table 4.

[0142]

Table 4

[0143] Example 2

[0141] Samples containing polyphenylene sulfide were formulated according to Table 5. The listed components were mixed in a Werner Pfleiderer ZSK 25 co-rotating intermeshing twin-screw extruder with a diameter of 32 mm.

[0144]

Table 5

[0145]

[0142] The obtained pellets were injection molded using a Mannesmann Demag D100 NCIII injection molding machine and tested for the specific physical characteristics shown in Table 6 below.

[0146]

Table 6

[0147]

[0143] Furthermore, the polymer formulation exhibits a relative permittivity of approximately 3.55 and a dielectric tangent of about 0.0075 at 2 GHz.

[0144] These and other modifications and variations of the present invention can be implemented by those skilled in the art without departing from the spirit and scope of the invention as more particularly set forth in the appended claims. Furthermore, it should be understood that aspects of the various embodiments are interchangeable, in whole or in part. Additionally, those skilled in the art will understand that the foregoing description is merely illustrative and thus does not limit the invention as further described in the appended claims. The description of the claims at the time of filing is shown below. [Claim 1] An antenna cover including a layer containing a polymer composition, the polymer composition including a polymer matrix containing at least one polymer having a glass transition temperature of about 50 °C or higher, the polymer matrix constituting about 30 wt.% to about 90 wt.% of the polymer composition, and the polymer composition exhibiting a relative permittivity of about 4 or less and a dielectric tangent of about 0.02 or less as determined at a frequency of 2 GHz. [Claim 2] The antenna cover according to claim 1, further including a further layer defining at least one opening, the layer being disposed on the further layer such that the further layer is formed over at least one of the at least one opening or received within at least one of the at least one opening. [Claim 3] The antenna cover according to claim 2, wherein the further layer is a conductive layer. [Claim 4] The antenna cover according to claim 2, wherein the further layer contains aluminum. [Claim 5] The antenna cover according to claim 1, wherein the polymer composition exhibits a relative permittivity of about 3.8 or less and a dielectric tangent of about 0.01 or less as determined at a frequency of 2 GHz. [Claim 6] The antenna cover according to claim 1, wherein the polymer comprises polyester, polyarylene sulfide, polyaryl ketone, or a mixture thereof, said antenna cover. [Claim 7] The antenna cover according to claim 1, wherein the polymer comprises a polyester containing polybutylene terephthalate, said antenna cover. [Claim 8] The antenna cover according to claim 7, wherein the polymer further comprises polyethylene terephthalate, said antenna cover. [Claim 9] The antenna cover according to claim 1, wherein the polymer comprises a polyarylene sulfide containing polyphenylene sulfide, said antenna cover. [Claim 10] The antenna cover according to claim 1, wherein the polymer composition further comprises at least one impact modifier comprising an epoxy-functionalized olefin copolymer, said antenna cover. [Claim 11] The antenna cover according to claim 10, wherein the epoxy-functionalized olefin copolymer comprises an epoxy-functional (meth)acrylic monomer component, said antenna cover. [Claim 12] The antenna cover according to claim 11, wherein the epoxy-functional (meth)acrylic monomer component is derived from glycidyl acrylate, glycidyl methacrylate, or a combination thereof, said antenna cover. [Claim 13] The antenna cover according to claim 10, wherein the epoxy-functionalized olefin copolymer contains ethylene monomer units, said antenna cover. [Claim 14] The antenna cover according to claim 10, wherein the epoxy-functionalized olefin copolymer further contains octene monomer units, said antenna cover. [Claim 15] The antenna cover according to claim 10, wherein the impact modifier is present in the polymer composition in an amount of about 1 wt.% to about 40 wt.%. [Claim 16] The antenna cover according to claim 1, wherein the polymer composition further comprises at least one dielectric filler in an amount of about 5 wt.% to about 40 wt.%. [Claim 17] The antenna cover according to claim 16, wherein at least one of the dielectric fillers comprises hollow glass spheres, glass flakes, or a mixture thereof. [Claim 18] The antenna cover according to claim 16, wherein at least one of the dielectric fillers comprises a polymer filler containing ultra-high molecular weight polyethylene. [Claim 19] The antenna cover according to claim 16, wherein at least one of the dielectric fillers comprises a polymer filler containing high density polyethylene. [Claim 20] The antenna cover according to claim 19, wherein the high density polyethylene particles have a D 50 value of from about 1 μm to about 300 μm. [Claim 21] The antenna cover according to claim 19, wherein the high density polyethylene particles have a molecular weight of from about 1,000,000 g / mol to about 10,000,000 g / mol. [Claim 22] The antenna cover according to claim 1, wherein the polymer composition further comprises a fibrous filler in an amount of about 3 wt.% to about 40 wt.%. [Claim 23] The antenna cover according to claim 22, wherein the fibrous filler comprises flat glass fibers having an aspect ratio of from about 1.5 to about 30. [Claim 24] The antenna cover according to claim 1, wherein the polymer composition further comprises an epoxy resin, the antenna cover. [Claim 25] The antenna cover according to claim 24, wherein the epoxy resin contains at least about 1.3 epoxide groups per molecule, the antenna cover. [Claim 26] The antenna cover according to claim 24, wherein the epoxy resin has a dynamic viscosity of about 1 centipoise to about 25 centipoise, a melting point of about 50 °C to about 120 °C, or both, determined at a temperature of 25 °C according to ASTM D445-15, the antenna cover. [Claim 27] The antenna cover according to claim 24, wherein the epoxy resin is a glycidyl ether formed from epichlorohydrin and a hydroxyl compound containing at least 1.5 aromatic hydroxyl groups, the antenna cover. [Claim 28] The antenna cover according to claim 27, wherein the hydroxyl compound is a dihydric phenol, the antenna cover. [Claim 29] The antenna cover according to claim 28, wherein the dihydric phenol is bisphenol A, the antenna cover. [Claim 30] The antenna cover according to claim 1, wherein the polymer composition has a density of less than about 2.5 kg / m 3 The antenna cover. [Claim 31] A user computing device including the antenna cover according to claim 1. [Claim 32] A base station including the antenna cover according to claim 1. [Claim 33] A method of forming the antenna cover according to claim 1, the method including the step of nano-molding the polymer composition on the surface of a further layer to form the layer. [Claim 34] The method according to claim 33, further comprising the step of surface-treating the surface of the further layer before nano-molding. [Claim 35] The method according to claim 34, wherein the surface treatment is a mechanical surface treatment. [Claim 36] The method according to claim 34, wherein the surface treatment is a chemical surface treatment. [Claim 37] The method according to claim 34, wherein the surface of the further layer exhibits a surface roughness of about 0.1 nm to about 500 nm. [Claim 38] Substrate An antenna element coupled to the substrate An antenna cover disposed on the substrate, the antenna cover including a layer containing a polymer composition, and A radio frequency component configured to operate at about 2.5 GHz or higher comprising wherein the polymer composition is a polymer matrix containing at least one polymer having a glass transition temperature of about 50 °C or higher, the polymer matrix constituting about 30 wt.% to about 90 wt.% of the polymer composition, A 5G radio frequency communication device, wherein the polymer composition exhibits a relative permittivity of about 4 or less and a dielectric tangent of about 0.02 or less determined at a frequency of 2 GHz. [Claim 39] The 5G radio frequency communication device according to claim 38, wherein the antenna cover includes a further layer defining an opening, the layer being formed on the further layer, and the antenna cover is disposed on the substrate such that the antenna element is at least partially aligned with the opening in the further layer or at least partially received in the opening in the further layer. [Claim 40] The 5G radio frequency communication device according to claim 38, wherein the radio frequency component is configured to operate at a frequency higher than 3 GHz, the 5G radio frequency communication device. [Claim 41] The 5G radio frequency communication device according to claim 38, wherein the radio frequency component is configured to operate at a frequency higher than 28 GHz, the 5G radio frequency communication device. [Claim 42] The 5G radio frequency communication device according to claim 38, wherein the radio frequency component includes at least one of a front-end module or an antenna, the 5G radio frequency communication device. [Claim 43] The 5G radio frequency communication device according to claim 38, wherein the radio frequency component is included in at least one of a base station, a user computing device, a relay station, or a repeater, the 5G radio frequency communication device. [Claim 44] A base station, including an antenna array, and an antenna cover disposed on the antenna array, the antenna cover including a layer including a polymer composition including at least one polymer having a glass transition temperature of about 50 °C or higher, the polymer matrix constituting about 30 wt.% to about 90 wt.% of the polymer composition, the polymer composition exhibiting a relative permittivity of about 4 or less and a dielectric loss tangent of about 0.02 or less determined at a frequency of 2 GHz, the base station.

Claims

1. An antenna cover including a layer containing a polymer composition, the polymer composition containing a polymer matrix containing at least one polymer having a glass transition temperature of 50° C. or higher, and a dielectric filler containing ultra-high molecular weight polyethylene, wherein the polymer matrix constitutes 30 wt.% to 90 wt.% of the polymer composition, the ultra-high molecular weight polyethylene constitutes 5 wt.% to 40 wt.% of the polymer composition, and the polymer includes polyester, polyarylene sulfide, or a combination thereof, the polymer composition further including a fibrous filler containing glass fiber in an amount of 1 wt.% to 40 wt.%, and at least one impact modifier containing an epoxy-functionalized olefin copolymer in an amount of 1 wt.% to 40 wt.%, and the antenna cover, wherein the polymer composition exhibits a relative permittivity of 4 or less and a dielectric tangent of 0.02 or less determined at a frequency of 2 GHz.

2. The antenna cover according to claim 1, further including a further layer defining at least one opening, wherein the layer containing the polymer composition is disposed on the further layer such that the layer containing the polymer composition is formed on top of the at least one opening or received within the at least one opening, at least one of which is the case.

3. The antenna cover according to claim 2, wherein the further layer is a conductive layer.

4. The antenna cover according to claim 2, wherein the further layer contains aluminum.

5. The antenna cover according to claim 1, wherein the polymer composition exhibits a relative permittivity of 3.8 or less and a dielectric tangent of 0.01 or less determined at a frequency of 2 GHz.

6. The antenna cover according to claim 1, wherein the polymer includes a polyester including polybutylene terephthalate.

7. The antenna cover according to claim 6, wherein the polymer further includes polyethylene terephthalate.

8. The antenna cover according to claim 1, wherein the polymer includes a polyarylene sulfide including polyphenylene sulfide.

9. The antenna cover according to claim 1, wherein the epoxy-functionalized olefin copolymer contains an epoxy-functional (meth)acrylic monomer component, said antenna cover.

10. The antenna cover according to claim 9, wherein the epoxy-functional (meth)acrylic monomer component is derived from glycidyl acrylate, glycidyl methacrylate or a combination thereof, said antenna cover.

11. The antenna cover according to claim 1, wherein the epoxy-functionalized olefin copolymer contains ethylene monomer units, said antenna cover.

12. The antenna cover according to claim 9, wherein the epoxy-functionalized olefin copolymer further contains octene monomer units, said antenna cover.

13. The antenna cover according to claim 1, wherein the dielectric filler further comprises hollow glass spheres, glass flakes or a mixture thereof, said antenna cover.

14. The antenna cover according to claim 1, wherein the polymer composition contains 3 wt.% to 40 wt.% of said fibrous filler, said antenna cover.

15. The antenna cover according to claim 14, wherein the fibrous filler comprises flat glass fibers having an aspect ratio of 1.5 to 30, said antenna cover.

16. The antenna cover according to claim 1, wherein the polymer composition further comprises an epoxy resin, said antenna cover.

17. The antenna cover according to claim 16, wherein the epoxy resin contains at least 1.3 epoxy groups per molecule, said antenna cover.

18. The antenna cover according to claim 16, wherein the epoxy resin has a dynamic viscosity of 1 centipoise to 25 centipoises, a melting point of 50°C to 120°C, or both, determined at a temperature of 25°C according to ASTM D445-15, said antenna cover.

19. The antenna cover according to claim 16, wherein the epoxy resin is a glycidyl ether formed from epichlorohydrin and a hydroxyl compound containing at least 1.5 aromatic hydroxyl groups, said antenna cover.

20. The antenna cover according to claim 19, wherein the hydroxyl compound is a dihydric phenol, said antenna cover.

21. The antenna cover according to claim 20, wherein the diphenol is bisphenol A, said antenna cover.

22. The antenna cover according to claim 1, wherein the polymer composition has a density of less than 2.5 kg / m ３ The antenna cover having the above density.

23. A user computing device including the antenna cover according to claim 1.

24. A base station including the antenna cover according to claim 1.

25. A method of forming the antenna cover according to claim 1, wherein the antenna cover includes a first layer capable of forming a further layer defined in claim 2, said method comprising: Nano-molding the polymer composition on the surface of the first layer to form the layer containing the polymer composition, said method.

26. The method according to claim 25, further comprising the step of surface-treating the surface of the first layer before nano-molding, said method.

27. The method according to claim 26, wherein the surface treatment is a mechanical surface treatment, said method.

28. The method according to claim 26, wherein the surface treatment is a chemical surface treatment, said method.

29. The method according to claim 26, wherein the surface of the first layer exhibits a surface roughness of 0.1 nm to 500 nm, said method.

30. A 5G radio frequency communication device, a substrate, an antenna element coupled to the substrate, an antenna cover disposed on the substrate, said antenna cover including a layer containing a polymer composition, and radio frequency components configured to operate at 2.5 GHz or higher comprising, wherein the polymer composition includes a polymer matrix containing at least one polymer having a glass transition temperature of 50 °C or higher and a dielectric filler including ultra-high molecular weight polyethylene, and the polymer matrix constitutes 30 wt.% to 90 wt.% of the polymer composition, and the ultra-high molecular weight polyethylene constitutes 5 wt.% to 40 wt.% of the polymer composition, and the polymer includes polyester, polyarylene sulfide, or a combination thereof, wherein the polymer composition further includes a fibrous filler including glass fibers in an amount of 1 wt.% to 40 wt.% and at least one impact modifier including an epoxy-functionalized olefin copolymer in an amount of 1 wt.% to 40 wt.%, and wherein the polymer composition exhibits a relative dielectric constant of 4 or less and a dielectric tangent of 0.02 or less determined at a frequency of 2 GHz, said 5G radio frequency communication device.

31. The 5G radio frequency communication device according to claim 30, wherein the antenna cover includes a further layer defining an opening, the layer including the polymer composition is formed on the further layer, and the antenna element is at least partially aligned with the opening in the further layer or at least partially received in the opening in the further layer, and the antenna cover is disposed on the substrate, the 5G radio frequency communication device.

32. The 5G radio frequency communication device according to claim 30, wherein the radio frequency component is configured to operate at a frequency higher than 3 GHz, the 5G radio frequency communication device.

33. The 5G radio frequency communication device according to claim 30, wherein the radio frequency component is configured to operate at a frequency higher than 28 GHz, the 5G radio frequency communication device.

34. The 5G radio frequency communication device according to claim 30, wherein the radio frequency component includes at least one of a front-end module or an antenna, the 5G radio frequency communication device.

35. The 5G radio frequency communication device according to claim 30, wherein the radio frequency component is included in at least one of a base station, a user computing device, a relay station, and a repeater, the 5G radio frequency communication device.

36. A base station, including an antenna array, and an antenna cover disposed on the antenna array wherein the antenna cover includes a layer including a polymer composition containing a polymer matrix having a glass transition temperature of 50 ° C or higher and a dielectric filler including ultra-high molecular weight polyethylene, and the polymer matrix is 30 wt. % to 90 wt. % of the polymer composition, the ultra-high molecular weight polyethylene constituting 5 wt. % to 40 wt. % of the polymer composition, and the polymer including polyester, polyarylene sulfide, or a combination thereof, the polymer composition further includes a fibrous filler including glass fiber in an amount of 1 wt. % to 40 wt. %, and at least one impact modifier including an epoxy-functionalized olefin copolymer in an amount of 1 wt. % to 40 wt. %, and ​ The base station, wherein the polymer composition exhibits a relative permittivity of 4 or less and a dielectric loss tangent of 0.02 or less determined at a frequency of 2 GHz.

37. An antenna cover including a layer containing a polymer composition, the polymer composition including a polymer matrix containing at least one polymer having a glass transition temperature of 50° C. or higher, the polymer matrix constituting 30 wt.% to 90 wt.% of the polymer composition, the polymer including a polyarylene sulfide, the polymer composition further including a fibrous filler containing glass fibers in an amount of 1 wt.% to 40 wt.%, and at least one impact modifier containing an epoxy-functionalized olefin copolymer in an amount of 1 wt.% to 40 wt.%, the polymer composition exhibits a relative permittivity of 4 or less and a dielectric loss tangent of 0.02 or less determined at a frequency of 2 GHz, and the composition does not include a hydrogenated product of a block copolymer composed of vinyl aromatic compound polymer block units and conjugated diene compound polymer block units, the antenna cover.

38. The antenna cover according to claim 37, wherein the polymer composition includes the fibrous filler in an amount of 3 wt.% to 40 wt.%.

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