CN116615500A

CN116615500A - Electronic module

Info

Publication number: CN116615500A
Application number: CN202180085345.XA
Authority: CN
Inventors: 大卫·W·伊斯特普; 亚伦·H·约翰逊
Original assignee: Ticona LLC
Current assignee: Ticona LLC
Priority date: 2020-12-17
Filing date: 2021-12-07
Publication date: 2023-08-18

Abstract

An electronic module is disclosed that includes a housing that houses at least one electronic component. The outer shell comprises a fiber-reinforced polymer composition comprising a polymer matrix comprising a thermoplastic polymer and a plurality of long reinforcing fibers distributed in the polymer matrix. The polymer composition exhibits a dielectric constant of about 4 or less and a dissipation factor of about 0.01 or less at a frequency of 2 GHz. Furthermore, the polymer composition exhibits about 20kJ/m as determined according to ISO test No. 179-1:2010 at a temperature of about 23 ℃ ² Or higher charpy unnotched impact strength.

Description

Electronic module

Cross Reference to Related Applications

The application claims the benefit of U.S. provisional patent application Ser. No. 63/126,598 at day 17 of 12 in 2020 and U.S. provisional patent application Ser. No. 63/171,604 at day 7 of 4 in 2021, which are incorporated herein by reference in their entireties.

Background

Electronic modules typically contain electronic components (e.g., printed circuit boards, antenna elements, radio frequency devices, sensors, light sensing and/or transmission elements (e.g., optical fibers), cameras, global positioning devices, etc.) that are received within a housing structure to protect them from weather effects, such as sunlight, wind, and moisture. Typically, such housings are formed of a material that allows electromagnetic signals (e.g., radio frequency signals or light) to pass through. While these materials are suitable for certain applications, problems still occur in higher frequency ranges, such as those associated with LTE or 5G systems. More specifically, most conventional materials having the required strength typically exhibit relatively high dissipation factors (loss tangent) and dielectric constants at high frequencies, which result in unacceptable levels of electromagnetic signal loss. Conversely, low loss materials tend to exhibit poor strength or have other problems, such as low flame retardancy. Thus, there is a need for improved electronic module materials.

Disclosure of Invention

According to one embodiment of the invention, an electronic module (e.g., an antenna module, a radar module, a lidar module, a camera module, etc.) is disclosed that includes a housing that houses at least one electronic component.The outer shell comprises a fiber-reinforced polymer composition comprising a polymer matrix comprising a thermoplastic polymer and a plurality of long reinforcing fibers distributed in the polymer matrix. The polymer composition exhibits a dielectric constant of about 4 or less and a dissipation factor of about 0.01 or less at a frequency of 2 GHz. In addition, the polymer composition exhibits about 20kJ/m ² Or higher charpy unnotched impact strength, as determined according to ISO test No. 179-1:2010 at a temperature of about 23 ℃.

Other features and aspects of the present invention are set forth in more detail below.

Drawings

A full and enabling disclosure of the present invention, including the best mode thereof to one skilled in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

FIG. 1 is a schematic view of one embodiment of a system that can be used to form the polymer compositions of the present invention;

FIG. 2 is a cross-sectional view of an impregnation die that may be used in the system shown in FIG. 1;

FIG. 3 is an exploded perspective view of one embodiment of an electronic module that can use the polymer composition of the present invention; and

fig. 4 depicts one embodiment of a 5G system in which the electronic module of the present invention may be employed.

Detailed Description

It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention.

Generally, the present invention relates to an electronic module that includes a housing that houses one or more electronic components (e.g., printed circuit boards, antenna elements, radio frequency sensing devices, sensors, light sensing and/or transmission elements (e.g., optical fibers), cameras, global positioning devices, etc.). The outer shell comprises a fiber-reinforced polymer composition comprising a polymer matrix comprising a thermoplastic polymer and a plurality of long reinforcing fibers distributed in the polymer matrix. By careful selection of the particular nature and concentration of the components of the polymer composition, the inventors have found that the resulting composition can exhibit low dielectric constants and dissipation factors over a broad frequency range. That is, the polymer composition may exhibit a low dielectric constant of about 4 or less, in some embodiments about 3.5 or less, in some embodiments about 0.1 to about 3.4, and in some embodiments about 1 to about 3.3, in some embodiments about 1.5 to about 3.2, in some embodiments about 2 to about 3.1, and in some embodiments about 2.5 to about 3.1 at high frequencies (e.g., 2 or 10 GHz). The dissipation factor of the polymer composition as a measure of the rate of energy loss may also be about 0.01 or less, in some embodiments about 0.009 or less, in some embodiments about 0.008 or less, in some embodiments about 0.007 or less, in some embodiments about 0.006 or less, and in some embodiments, about 0.001 to about 0.005 at high frequencies (e.g., 2 or 10 GHz).

In general, it is believed that polymer compositions exhibiting low dissipation factors and dielectric constants will not also have adequate mechanical properties. However, the inventors have found that the polymer composition is capable of maintaining excellent mechanical properties. For example, the polymer composition may exhibit about 20kJ/m ² Or higher, in some embodiments from about 30 to about 80kJ/m ² And in some embodiments from about 40 to about 60kJ/m ² The Charpy unnotched impact strength is measured according to ISO test number 179-1:2010 (technically equivalent to ASTM D256-10e 1) at various temperatures, such as in a temperature range of about-50 ℃ to about 85 ℃ (e.g., -40 ℃ or 23 ℃). Tensile and flexural mechanical properties may also be good. For example, the polymer composition may exhibit: a tensile strength of about 50MPa or greater than 300MPa, in some embodiments from about 80 to about 500MPa, and in some embodiments, from about 85 to about 250MPa; a tensile strain at break of about 0.5% or greater, in some embodiments from about 0.6% to about 5%, and in some embodiments, from about 0.7% to about 2.5%; and/or a tensile modulus of about 3500MPa to about 20000MPa, in some embodiments about 6000MPa to about 15000MPa, and in some embodiments In the example from about 8000MPa to about 15000MPa. Tensile properties may be determined according to ISO test number 527-1:2019 (technically equivalent to ASTM D638-14) at various temperatures, for example, in a temperature range of about-50℃to about 85 ℃ (e.g., -40℃or 23 ℃). The polymer composition may also exhibit: a flexural strength of about 100 to about 500MPa, in some embodiments about 130 to about 400MPa, and in some embodiments, about 140 to about 250MPa; a bending fracture strain of about 0.5% or greater, in some embodiments from about 0.6% to about 5%, and in some embodiments, from about 0.7% to about 2.5%; and/or a flexural modulus of about 4500MPa to about 20000MPa, in some embodiments about 5000MPa to about 15000MPa, and in some embodiments, about 5500MPa to about 12000MPa. Bending properties may be measured according to ISO test number 178:2019 (technically equivalent to ASTM D790-17) at various temperatures, for example, in a temperature range of about-50 ℃ to about 85 ℃ (e.g., -40 ℃ or 23 ℃).

The polymer composition may also be less susceptible to aging at low or high temperatures. For example, the composition may be aged in an atmosphere having a temperature of about-50 ℃ to about 85 ℃ (e.g., -40 ℃ or 85 ℃) for about 100 hours or more, in some embodiments about 300 hours to about 3000 hours, and in some embodiments, about 400 hours to about 2500 hours (e.g., 500 or 1000 hours). Mechanical properties (e.g., impact strength, tensile properties, and/or flexural properties) may remain within the above ranges even after aging. For example, the ratio of a particular mechanical property after "aging" at 150 ℃ for 1000 hours (e.g., charpy notched impact strength, tensile strength, flexural strength, etc.) to the initial mechanical property prior to such aging may be about 0.6 or greater, in some embodiments about 0.7 or greater, and in some embodiments, about 0.8 to 1.0. Similarly, the polymer composition is not highly sensitive to ultraviolet light. For example, the polymer composition may be exposed to one or more ultraviolet light cycles as described above. Even after such exposure (e.g., according to SAE J2527_2017092, the total exposure level is 2500kJ/m ² ) Mechanical properties (e.g., impact strength, tensile strength, flexural strength, etc.) and ratios of these properties may still be maintained as noted aboveWithin a range of (2).

The polymer composition may also be flame retardant. For example, the extent to which a composition can extinguish a fire ("charring") can be expressed in terms of its limiting oxygen index (Limiting Oxygen Index, "LOI"), which is the volume percent of oxygen required to support combustion. More specifically, the polymer composition may have an LOI of about 25 or greater, in some embodiments about 27 or greater, in some embodiments about 28 or greater, and in some embodiments, about 30 to 100, as determined according to ISO 4589:2017 (technically equivalent to ASTM D2863-19). Flame retardancy may also be characterized according to the procedure of Underwriter's Laboratory Bulletin 94 entitled "flammability test of plastic materials, UL 94". Multiple levels may be applied depending on the extinguishing time (total flame time of a set of 5 samples) and anti-drip capability, as described in more detail below. According to this procedure, for example, as discussed in more detail below, the polymer composition may exhibit at least a V1 rating, and preferably a V0 rating, at a part thickness (e.g., 3 millimeters). For example, the composition may exhibit a total flame time of about 250 seconds or less (V1 rating), in some embodiments about 100 seconds or less, and in some embodiments about 50 seconds or less (V0 rating).

In certain embodiments, the composition may also provide a high degree of shielding effectiveness against electromagnetic interference (Electromagnetic interference, "EMI"). More specifically, the EMI shielding effectiveness may be about 20 decibels (dB) or greater, in some embodiments about 25dB or greater, and in some embodiments, about 30dB to about 100dB, as determined at 2GHz frequency according to ASTM D4935-18. In addition to exhibiting good EMI shielding effectiveness, the composition may also exhibit a relatively low volume resistivity, such as about 5000ohm-cm or less, in some embodiments about 1000ohm-cm or less, and in some embodiments, about 50 to about 800ohm-cm, as determined according to ASTM D257-14.

Various embodiments of the present invention will now be described in more detail.

I Polymer matrix

A. Thermoplastic polymers

The polymer matrix serves as the continuous phase of the composition and comprises one or more thermoplastic polymers, such as propylene polymers, polyamides, polyarylene sulfides, polyaryletherketones (e.g., polyetheretherketones), polycarbonates, polybutadiene resins (e.g., acrylonitrile-butadiene-styrene copolymers), and the like. In one embodiment, for example, propylene polymers may be particularly suitable. When used, the propylene polymer may comprise, for example, from about 30 wt% to about 80 wt%, in some embodiments from about 45 wt% to about 75 wt%, and in some embodiments, from about 50 wt% to about 70 wt%, and from about 30 wt% to about 65 wt%, in some embodiments, from about 35 wt% to about 60 wt%, and in some embodiments, from about 40 wt% to about 55 wt%, based on the total polymer composition.

Any of a variety of propylene polymers or combinations of propylene polymers may generally be used in the polymer matrix, such as propylene homopolymers (e.g., syndiotactic, atactic, isotactic, etc.), propylene copolymers, and the like. In one embodiment, for example, propylene polymers of isotactic or syndiotactic homopolymers may be used. The term "syndiotactic" generally refers to a degree of tacticity in which a substantial portion, if not all, of the methyl groups alternate on opposite sides along the polymer chain. On the other hand, the term "isotactic" generally refers to a degree of tacticity in which a substantial portion, if not all, of the methyl groups are located on the same side of the polymer chain. Such homopolymers may have a melting point of about 160 ℃ to about 170 ℃. In still other embodiments, copolymers of propylene with alpha-olefin monomers may be used. Specific examples of suitable alpha-olefin monomers may include ethylene, 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 with one or more methyl, ethyl or propyl substituents; 1-heptene having one or more methyl, ethyl or propyl substituents; 1-octene with 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. The propylene content of such copolymers may be from about 60 mole% to about 99 mole%, in some embodiments from about 80 mole% to about 98.5 mole%, and in some embodiments, from about 87 mole% to about 97.5 mole%. The alpha-olefin content may likewise be from about 1 mole% to about 40 mole%, in some embodiments from about 1.5 mole% to about 15 mole%, and in some embodiments, from about 2.5 mole% to about 13 mole%. Propylene polymers generally have a high flowability to help facilitate molding the composition into small parts. The high flow propylene polymer may, for example, have a relatively high melt flow index, such as about 150 grams per 10 minutes or higher, in some embodiments about 180 grams per 10 minutes or higher, and in some embodiments, about 200 to about 500 grams per 10 minutes, as determined according to ISO 1133-1:2011 (technically equivalent to ASTM D1238-13) at a load of 2.16 kilograms and a temperature of 230 ℃.

Any of a variety of known techniques may generally be used to form the propylene copolymer. For example, such polymers may be formed using free radicals or coordination catalysts (e.g., ziegler-natta). In some embodiments, for example, the polymer may be formed from a single site coordination catalyst, such as a metallocene catalyst. Such a catalyst system produces a copolymer in which the comonomer is randomly distributed within the molecular chain and uniformly distributed in the different molecular weight fractions. Examples of the metallocene catalyst include bis (n-butylcyclopentadienyl) titanium dichloride, bis (n-butylcyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) scandium chloride, bis (indenyl) zirconium dichloride, bis (methylcyclopentadienyl) titanium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, cobaltocene, cyclopentadienyl titanium trichloride, ferrocene, hafnocene dichloride, isopropyl (cyclopentadienyl, -1-fluorenyl) zirconium dichloride, molybdenum dichloride, nickel dichloride, niobium dichloride, ruthenium dichloride, titanocene dichloride, zirconocene hydrogen dichloride, zirconocene dichloride, and the like. Polymers prepared using metallocene catalysts typically have a narrow molecular weight range. For example, the metallocene-catalyzed polymers may have a polydispersity number (Mw/Mn) of less than 4, a controlled short chain branching distribution, and a controlled isotacticity.

It can also be usedHe polymer. In some embodiments, for example, the polymer matrix may comprise a polycarbonate, which generally comprises the formula-R ¹ -repeating structural carbonate units of O-C (O) -O-. The polycarbonate may be aromatic, since R ¹ At least a portion (e.g., 60% or more) of the total number of groups comprises an aromatic moiety and the remainder of which is aliphatic, alicyclic, or aromatic. In one embodiment, for example, R ¹ May be C _6-30 An aromatic group, i.e. comprising at least one aromatic moiety. In general, R ¹ Derived from the general formula HO-R ¹ Dihydroxyaromatic compounds of the formula-OH, for example compounds having the following specific general formula:

HO-A ¹ -Y ¹ -A ² -OH

wherein,,

A ¹ and A ² Independently a monocyclic divalent aryl group; and

Y ¹ is a single bond or has one or more groups A ¹ And A is a ² Bridging groups of separate atoms. In a particular embodiment, the dihydroxy aromatic compound may be derived from the following formula (I):

wherein,,

R ^a and R is ^b Each independently is halogen or C _1-12 Alkyl groups, e.g. C, meta to the hydroxy group on each arylene group _1-3 Alkyl (e.g., methyl);

p and q are each independently 0 to 4 (e.g., 1); and

X ^a represents a bridging group linking two hydroxy-substituted aromatic groups, wherein the bridging group and each C ₆ The hydroxy substituent of arylene group being at C ₆ Ortho, meta or para (particularly para) to the arylene group.

In one embodiment, X ^a May be substituted or unsubstituted C _3-18 Cycloalkylene radicals of the formula-C (R) ^c )(R ^d ) C of _1-25 Alkylene group, wherein R is ^c And R is ^d Each independently is hydrogen, C _1-12 Alkyl, C _1-12 Cycloalkyl, C _7-12 Arylalkyl, C _7-12 Heteroalkyl, or cyclic C _7-12 Heteroarylalkyl, or of formula-C (=r ^e ) -a group wherein R ^e Is divalent C _1-12 A hydrocarbon group. Exemplary groups of this type include methylene, cyclohexylmethylene, ethylene, neopentylene and isopropylidene, and 2- [2.2.1]-bicycloheptyl, cyclohexyl, cyclopentyl, cyclododecyl and adamantyl. Wherein X is ^a Specific examples of substituted cycloalkylene are cyclohexylidene-bridged alkyl-substituted bisphenols of the following formula (II):

wherein,,

R ^a' and R is ^b' Each independently is C _1-12 Alkyl (e.g. C _1-4 Alkyl, such as methyl), and may optionally be located meta to the cyclohexylidene bridge;

R ^g is C _1-12 Alkyl (e.g. C _1-4 Alkyl) or halogen;

r and s are each independently 1 to 4 (e.g., 1); and

t is 0 to 10, such as 0 to 5.

The cyclohexylidene-bridged bisphenol may be the reaction product of two moles of o-cresol with one mole of cyclohexanone. In another embodiment, the cyclohexylidene-bridged bisphenol can be the reaction product of two moles of cresol with one mole of hydrogenated isophorone (e.g., 1, 3-trimethyl-3-cyclohexane-5-one). Such cyclohexane-containing bisphenols, for example, the reaction product of two moles of phenol with one mole of hydrogenated isophorone, can be used to prepare polycarbonate polymers having high glass transition temperatures and high heat distortion temperatures.

In another embodiment, X ^a May be C _1-18 Alkylene, C _3-18 Cycloalkylene, fused C _6-18 Cycloalkylene radicals or of the formula-B ¹ -W-B ² -a group of the formulaB in (B) ¹ And B ² Independently C _1-6 Alkylene group, W is C _3-12 Cycloalkylene or C _6-16 Arylene groups.

X ^a May also be substituted C of the formula (III) _3-18 Cycloalkylene radicals:

wherein,,

R ^r 、R ^p 、R ^q and R is ^t Each independently is hydrogen, halogen, oxygen or C _1-12 An organic group;

i is a direct bond, carbon or divalent oxygen, sulfur or-N (Z) -, wherein Z is hydrogen, halogen, hydroxy, C _1-12 Alkyl, C _1-12 Alkoxy or C _1-12 An acyl group;

h is 0 to 2;

j is 1 or 2;

i is 0 or 1; and

k is 0 to 3, provided that R ^r 、R ^p 、R ^q And R is ^t Is a fused cycloaliphatic, aromatic or heteroaromatic ring.

Other useful aromatic dihydroxy aromatic compounds include those having the following formula (IV):

wherein,,

R ^h independently a halogen atom (e.g. bromine), C _1-10 Hydrocarbyl radicals (e.g. C _1-10 Alkyl), halogen substituted C _1-10 Alkyl, C _6-10 Aryl-or halogen-substituted C _6-10 An aryl group;

n is 0 to 4.

Specific examples of bisphenol compounds of formula (I) include, for example, 1-bis (4-hydroxyphenyl) methane, 1-bis (4-hydroxyphenyl) ethane, 2-bis (4-hydroxyphenyl) propane (hereinafter referred to as "bisphenol A" or "BPA") ") 2, 2-bis (4-hydroxyphenyl) butane, 2-bis (4-hydroxyphenyl) octane, 1-bis (4-hydroxyphenyl) propane, 1-bis (4-hydroxyphenyl) n-butane, 2-bis (4-hydroxy-1-methylphenyl) propane 1, 1-bis (4-hydroxy-tert-butylphenyl) propane, 3-bis (4-hydroxyphenyl) phthalimide, 2-phenyl-3, 3-bis (4-hydroxyphenyl) phthalimide (PPPBP) and 1, 1-bis (4-hydroxy-3-methylphenyl) cyclohexane (DMBPC). In one embodiment, the polycarbonate may be a linear homopolymer derived from bisphenol A, in which A ¹ And A ² Each is p-phenylene, Y ¹ Is isopropylidene in formula (I).

Other examples of suitable aromatic dihydroxy compounds may include, but are not limited to, 4 '-dihydroxybiphenyl, 1, 6-dihydroxynaphthalene, 2, 6-dihydroxynaphthalene, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) -1-naphthylmethane, 1, 2-bis (4-hydroxyphenyl) ethane, 1-bis (4-hydroxyphenyl) -1-phenylethane, 2- (4-hydroxyphenyl) -2- (3-hydroxyphenyl) propane bis (4-hydroxyphenyl) phenylmethane, 2-bis (4-hydroxy-3-bromophenyl) propane, 1-bis (hydroxyphenyl) cyclopentane, 1-bis (4-hydroxyphenyl) cyclohexane 1, 1-bis (4-hydroxyphenyl) isobutylene, 1-bis (4-hydroxyphenyl) cyclododecane, trans-2, 3-bis (4-hydroxyphenyl) -2-butene, 2-bis (4-hydroxyphenyl) adamantane, alpha, alpha' -bis (4-hydroxyphenyl) toluene, bis (4-hydroxyphenyl) acetonitrile, 2-bis (3-methyl-4-hydroxyphenyl) propane, 2-bis (3-ethyl) -4-hydroxyphenyl) propane, 2, 2-bis (3-n-propyl-4-hydroxyphenyl) propane, 2, 2-bis (3-isopropyl-4-hydroxyphenyl) propane, 2-bis (3-sec-butyl-4-hydroxyphenyl) propane, 2-bis (3-tert-butyl-4-hydroxyphenyl) propane 2, 2-bis (3-cyclohexyl-4-hydroxyphenyl) propane, 2-bis (3-allyl-4-hydroxyphenyl) propane, 2-bis (3-methoxy-4-hydroxyphenyl) propane, 2-bis (4-hydroxyphenyl) hexafluoropropane, 1, 1-dichloro-2, 2-bis (4-hydroxyphenyl) ethylene, 1-dibromo-2, 2-bis (4-hydroxyphenyl) ethylene, 1-dichloro-2, 2-bis (5-phenoxy-4-hydroxyphenyl) ethylene 4,4' -dihydroxybenzophenone, 3-bis (4-hydroxyphenyl) -2-butanone, 1, 6-bis (4-hydroxyphenyl) -1, 6-hexanedione, ethyleneglycol bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfone, substituted resorcinol compounds such as 9, 9-bis (4-hydroxyphenyl) fluoro, 2, 7-dihydroxypyrene, 6 '-dihydroxy-3, 3' -tetramethylspiro (bis) indane ("spirobiindane bisphenol"), 3-bis (4-hydroxyphenyl) phthalimide, 2, 6-dihydroxydibenzo-p-dioxin, 2, 6-dihydroxythianthrene, 2, 7-dihydroxyphenoxacin, 2, 7-dihydroxy-9, 10-dimethylphenazine, 3, 6-dihydroxydibenzofuran, 3, 6-dihydroxydibenzothiophene, 2, 7-dihydroxycarbazole, resorcinol, 5-methylresorcinol, 5-ethylresorcinol, 5-propylresorcinol, 5-butylresorcinol, 5-t-butylresorcinol, 5-phenylresorcinol, 5-cumylresorcinol, 2,4,5, 6-tetrafluororesorcinol, 2,4,5, 6-tetrabromoresorcinol, and the like; catechol; hydroquinone; substituted hydroquinones, for example, 2-methyl hydroquinone, 2-ethyl hydroquinone, 2-propyl hydroquinone, 2-butyl hydroquinone, 2-t-butyl hydroquinone, 2-phenyl hydroquinone, 2-cumyl hydroquinone, 2,3,5, 6-tetramethyl hydroquinone, 2,3,5, 6-tetra-t-butyl hydroquinone, 2,3,5, 6-tetrafluoro hydroquinone, 2,3,5, 6-tetrabromo hydroquinone, and the like, and combinations thereof.

The aromatic polycarbonates described above generally have an intrinsic viscosity of about 0.1dl/g to about 6dl/g, in some embodiments about 0.2 to about 5dl/g, and in some embodiments, about 0.3 to about 1dl/g, as measured, for example, according to ISO 1628-4:1998. Aromatic polycarbonates also generally have higher glass transition temperatures and vicat softening temperatures than the aromatic polyesters present in the polymer matrix. For example, the aromatic polycarbonate may have a glass transition temperature of about 50 ℃ to about 250 ℃, in some embodiments about 90 ℃ to about 220 ℃, and in some embodiments about 100 ℃ to about 200 ℃, the glass transition temperature being determined, for example, by ISO 11357-2:2013, and a vicat softening temperature of about 50 ℃ to about 250 ℃, in some embodiments about 90 ℃ to about 220 ℃, and in some embodiments, about 100 ℃ to about 200 ℃, the vicat softening temperature being determined, for example, according to ISO 306:2004.

Polybutadiene may also be used in the polymer matrix, as described above. For example, in one embodiment, the polymer matrix may comprise a blend of polycarbonate and polybutadiene. When such blends are used, the polycarbonate may, for example, comprise from about 40 wt% to about 95 wt%, in some embodiments from about 60 wt% to about 92 wt%, and in some embodiments, from about 70 wt% to about 90 wt%, and from about 30 wt% to about 75 wt%, in some embodiments, from about 35 wt% to about 70 wt%, and in some embodiments, from about 40 wt% to about 65 wt% of the overall polymer composition. Likewise, polybutadiene can comprise from about 5 wt.% to about 60 wt.%, in some embodiments from about 8 wt.% to about 40 wt.%, and in some embodiments, from about 10 wt.% to about 30 wt.%, and from about 1 wt.% to about 25 wt.%, in some embodiments, from about 2 wt.% to about 20 wt.%, and in some embodiments, from about 3 wt.% to about 15 wt.% of the overall polymer composition of the blend. Suitable polybutadiene polymers are described in U.S. patent publication 2016/028061 to Brambrink et al, and may include, for example, copolymers comprising butadiene monomers in combination with styrene monomers (e.g., styrene, alpha-methylstyrene, alkyl-substituted styrene, etc.) and/or nitrile monomers (e.g., acrylonitrile, methacrylonitrile, alkyl-substituted acrylonitrile, etc.). For example, the butadiene copolymer may be a polybutadiene rubber grafted with styrene and/or acrylonitrile, such as acrylonitrile-butadiene-styrene ("ABS").

B. Flame retardant systems

In addition to the above components, the polymer matrix may also contain a flame retardant system to help achieve the desired flammability performance. When used, the flame retardant system generally comprises from about 5% to about 60%, in some embodiments from about 6% to about 50%, in some embodiments from about 8% to about 35%, and in some embodiments, from about 10% to about 30%, by weight of the polymer matrix, and from about 1% to about 50%, in some embodiments, from about 5% to about 30%, and in some embodiments, from about 10% to about 25% by weight of the overall polymer composition. The flame retardant system generally comprises at least one low halogen flame retardant. The halogen (e.g., bromine, chlorine, and/or fluorine) content of such agents is about 1500 parts per million by weight ("ppm") or less, in some embodiments about 900ppm or less, and in some embodiments about 50ppm or less. In certain embodiments, the flame retardant is completely halogen-free (i.e., 0 ppm). The particular properties of the halogen-free flame retardant can be selected to help achieve the desired flammability without adversely affecting the dielectric properties (e.g., dielectric constant, dissipation factor, etc.) and mechanical properties of the polymer composition.

For example, the system may comprise one or more organophosphorus flame retardants, such as phosphates, phosphate esters, phosphonates, phosphonate amines, phosphazenes, phosphinates, and the like, as well as mixtures thereof. In one embodiment, the organophosphorus flame retardant may be a nitrogen-containing phosphate formed from the reaction of a nitrogen-containing base with phosphoric acid. Suitable nitrogen-containing bases can include those having a substituted or unsubstituted ring structure, along with at least one nitrogen heteroatom (e.g., heterocycle or heteroaryl) and/or at least one nitrogen-containing functional group (e.g., amino, acylamino, etc.) in the ring structure being substituted at a carbon atom and/or heteroatom of the ring structure. Examples of such heterocyclic groups may include, for example, pyrrolidine, imidazoline, pyrazolidine, oxazolidine, isoxazolidine, thiazolidine, isothiazolidine, piperidine, piperazine, thiomorpholine and the like. Likewise, examples of heteroaryl groups may include, for example, pyrrole, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, triazole, furan, oxadiazole, tetrazole, pyridine, diazine, oxazine, triazine, tetrazine, and the like. The ring structure of the base may also be substituted with one or more functional groups, such as acyl, acyloxy, amido, alkoxy, alkenyl, alkyl, amino, aryl, aryloxy, carboxyl ester, cycloalkyl, hydroxyl, halogen, haloalkyl, heteroaryl, heterocyclyl, and the like, if desired. Substitution may occur at heteroatoms and/or carbon atoms of the ring structure.

One suitable nitrogen-containing base is melamine, which contains a 1,3,5 triazine ring structure, substituted on each of three carbon atoms with an amino function. Examples of suitable melamine phosphates may include, for example, melamine orthophosphates, melamine pyrophosphates, melamine polyphosphates, and the like. The melamine pyrophosphate may, for example, comprise about a 1:2 molar ratio of pyrophosphate to melamine. Another suitable nitrogen-containing base is piperazine, which is a six-membered ring structure containing two nitrogen atoms in the opposite positions of the ring. Examples of suitable piperazine phosphates may include, for example, piperazine orthophosphate, piperazine pyrophosphate, piperazine polyphosphate, and the like. Piperazine pyrophosphate may, for example, comprise pyrophosphate to melamine in a molar ratio of about 1:1. In certain embodiments, a blend of melamine and piperazine phosphate can be used in a flame retardant system. The flame retardant system may, for example, comprise one or more piperazine phosphate salts (e.g., piperazine pyrophosphate) in an amount of about 40 wt.% to about 90 wt.%, in some embodiments about 50 wt.% to about 80 wt.%, and one or more melamine phosphate salts (e.g., melamine pyrophosphate) in an amount of about 10 wt.% to about 60 wt.%, in some embodiments about 20 wt.% to about 50 wt.%, and in some embodiments about 25 wt.% to about 45 wt.%.

Of course, other organophosphorus flame retardants may also be used. For example, in one embodiment, monomeric and oligomeric phosphates and phosphonates may be used, such as tributyl phosphate, triphenyl phosphate, tricresyl phosphate, diphenyl cresyl phosphate, diphenyl octyl phosphate, diphenyl 2-ethyl cresyl phosphate, tri (isopropyl phenyl) phosphate, resorcinol bridged oligomeric phosphates, bisphenol a phosphate (e.g., bisphenol a bridged oligomeric phosphate or bisphenol a bis (diphenyl phosphate)), and the like, as well as mixtures thereof. Phosphinates, such as phosphinates and/or diphosphinates, may be used. Particularly suitable phosphinates include, for example, dimethyl phosphinic acid, ethyl methyl phosphinic acid, diethyl phosphinic acid, methyl-n-propyl phosphinic acid, methane-bis (methyl phosphinic acid), ethane-1, 2-bis (methyl phosphinic acid), hexane-1, 6-bis (methyl phosphinic acid), benzene-1, 4-bis (methyl phosphinic acid), methylphenyl phosphinic acid, diphenyl phosphinic acid, hypophosphorous acid, and the like. The resulting salt is typically a monomeric compound; however, polymeric phosphinates may also be formed. Particularly suitable phosphinates are zinc diethylphosphinate or aluminum diethylphosphinate.

In certain embodiments, the flame retardant system may be formed entirely of organophosphorus flame retardants, such as those described above. However, in other cases, the organophosphorus flame retardant may be used in combination with one or more additional additives. In such embodiments, the organophosphorus compound may constitute from about 50% to about 99.5%, in some embodiments from about 70% to about 99%, and in some embodiments, from about 80% to about 95%, by weight of the flame retardant system, and may constitute from about 1% to about 30%, in some embodiments, from about 2% to about 25%, and in some embodiments, from about 5% to about 20% by weight of the polymer matrix.

One suitable type of additive that may be used is an inorganic compound that may be used as a low halogen char-forming agent and/or smoke suppressant. Suitable inorganic compounds (anhydrous or hydrated) may include, for example, inorganic molybdates such as zinc molybdate (e.g., under the namePurchased from Huber Engineered Materials), calcium molybdate, ammonium octamolybdate, zinc molybdate-magnesium silicate, and the like. Other suitable inorganic compounds may include inorganic borates, such as zinc borate (which may be named +.>Commercial) and the like; zinc phosphate, zinc hydrogen phosphate, zinc pyrophosphate, basic zinc (VI) chromate (zinc yellow), zinc chromite, zinc permanganate, silica, magnesium silicate, calcium carbonate, zinc oxide, titanium dioxide, magnesium hydroxide, and the like. In certain embodiments, it may be desirable to use inorganic zinc compounds, such as zinc molybdate, zinc borate, zinc oxide, and the like, to enhance the overall performance of the composition. When used, such inorganic compounds (e.g., zinc oxide) may comprise, for example, from about 1 wt% to about 20 wt%, in some embodiments from about 2 wt% to about 15 wt%, and in some embodiments, from about 3 wt% to about 10 wt% of the flame retardant system.

Another suitable additive is a nitrogen-containing synergist which may act together with an organophosphorus flame retardant and/or other components to form a more efficient flame retardant system. Such nitrogen-containing synergists may include those of formulae (III) to (VIII), or mixtures thereof:

wherein,,

R ₅ 、R ₆ 、R ₇ 、R ₉ 、R ₁₀ 、R ₁₁ 、R ₁₂ and R is ₁₃ Independently is: hydrogen; c (C) ₁ -C ₈ An alkyl group; c (C) ₅ -C ₁₆ -cycloalkyl or alkylcycloalkyl, optionally substituted by hydroxy or C ₁ -C ₄ Hydroxyalkyl substitution; c (C) ₂ -C ₈ Alkenyl groups; c (C) ₁ -C ₈ Alkoxy, acyl or acyloxy; c (C) ₆ -C ₁₂ -aryl or arylalkyl; OR (OR) ⁸ Or N (R) ⁸ )R ⁹ Wherein R is ⁸ Is hydrogen, C ₁ -C ₈ Alkyl, C ₅ -C ₁₆ Cycloalkyl or alkylcycloalkyl, optionally substituted by hydroxy or C ₁ -C ₄ Hydroxyalkyl, C ₂ -C ₈ Alkenyl, C ₁ -C ₈ Alkoxy, acyl or acyloxy, or C ₆ -C ₁₂ Aryl or arylalkyl substitution;

m is 1 to 4;

n is 1 to 4;

x is an acid which can form an adduct with the triazine compound of formula III. For example, the nitrogen-containing synergist may include benzoguanamine, tris (hydroxyethyl) isocyanurate, allantoin, glycoluril, melamine cyanurate, dicyandiamide, guanidine, and the like. Examples of such synergists are described in U.S. Pat. No. 6,365,071 to Jenewein et al, U.S. Pat. No. 7,255,814 to Hoerold et al, and U.S. Pat. No. 7,259,200 to Bauer et al. One particularly suitable synergist is melamine cyanurate, e.g. available under the name BASF MC is commercially available (e.g.)>MC 15、MC25、MC50)。

As described above, the flame retardant system and/or the polymer composition itself typically has a relatively low level of halogen (i.e., bromine, fluorine, and/or chlorine), for example, about 15000 parts per million ("ppm") or less, in some embodiments about 5000ppm or less, in some embodiments about 1000ppm or less, in some embodiments about 800ppm or less, and in some embodiments, about 1ppm to about 600ppm. However, in certain embodiments of the present invention, halogen-based flame retardants may still be used as an optional component. Particularly suitable halogen-based flame retardants are fluoropolymers such as Polytetrafluoroethylene (PTFE), fluorinated Ethylene Polypropylene (FEP) copolymers, perfluoroalkoxy (PFA) resins, polychlorotrifluoroethylene (PCTFE) copolymers, ethylene-chlorotrifluoroethylene (ECTFE) copolymers, ethylene-tetrafluoroethylene (ETFE) copolymers, polyvinylidene difluoride (PVDF), polyvinyl fluoride (PVF) and copolymers and blends and other combinations thereof. When used, such halogen-based flame retardants typically comprise only about 10 wt.% or less, in some embodiments about 5 wt.% or less, and in some embodiments about 1 wt.% or less of the flame retardant system. Likewise, the halogen-based flame retardant typically comprises about 5 wt% or less, in some embodiments about 1 wt% or less, and in some embodiments about 0.5 wt% or less of the total polymer composition.

C. Stabilizer system

Although not required, the polymer matrix may also contain a stabilizer system to help maintain the desired surface appearance and/or mechanical properties even after exposure to ultraviolet light and high temperatures. More specifically, the stabilizer system may include one or more antioxidants (e.g., hindered phenol antioxidants, phosphite antioxidants, thioester antioxidants, etc.) and/or ultraviolet light stabilizers, as well as various other optional light stabilizers, optional heat stabilizers, and the like.

i. Antioxidant agent

One type of antioxidant that may be used in the polymer composition is a sterically hindered phenol. When used, the hindered phenol is generally present in an amount of from about 0.01 to about 1 weight percent, in some embodiments from about 0.02 to about 0.5 weight percent, and in some embodiments, from about 0.05 to about 0.3 weight percent, based on the polymer composition. Although a variety of different compounds may be used, particularly suitable hindered phenol compounds are those having one of the following formulas (IV), (V) and (VI):

wherein,,

a. b and c are independently 1 to 10, and in some embodiments, 2 to 6;

R ⁸ 、R ⁹ 、R ¹⁰ 、R ¹¹ and R is ¹² Independently selected from hydrogen, C ₁ To C ₁₀ Alkyl and C ₃ To C ₃₀ Branched alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, or tert-butyl moieties; and

R ¹³ 、R ¹⁴ and R is ¹⁵ Independently selected from moieties represented by one of the following formulas (VII) and (VIII):

wherein,,

d ranges from 1 to 10, and in some embodiments, from 2 to 6;

R ¹⁶ 、R ¹⁷ 、R ¹⁸ and R is ¹⁹ Independently selected from hydrogen, C ₁ To C ₁₀ Alkyl and C ₃ To C ₃₀ Branched alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl or tert-butyl moieties.

Specific examples of suitable hindered phenols having the above general structure may include, for example, 2, 6-di-t-butyl-4-methylphenol; 2, 4-di-tert-butylphenol; pentaerythritol tetrakis (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate; octadecyl-3- (3 ',5' -di-tert-butyl-4 ' -hydroxyphenyl) propionate; tetrakis [ methylene (3, 5-di-tert-butyl-4-hydroxycinnamate) ] methane; bis-2, 2' -methylene-bis (6-tert-butyl-4-methylphenol) terephthalate; 1,3, 5-trimethyl-2, 4, 6-tris (3, 5-di-tert-butyl-4-hydroxybenzyl) benzene; tris (3, 5-di-tert-butyl-4-hydroxybenzyl) isocyanurate; 1,3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) 1,3, 5-triazine-2, 4,6- (1 h,3h,5 h) -trione; 1, 3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane; 1,3, 5-triazine-2, 4,6 (1 h,3h,5 h) -trione; 1,3, 5-tris [ [3, 5-bis- (1, 1-dimethylethyl) -4-hydroxyphenyl ] methyl ];4,4',4"- [ (2, 4, 6-trimethyl-1, 3, 5-benzenetriyl) tris- (methylene) ] tris [2, 6-bis (1, 1-dimethylethyl) ]; 6-tert-butyl-3-methylphenyl; 2, 6-di-tert-butyl-p-cresol; 2,2' -methylenebis (4-ethyl-6-tert-butylphenol); 4,4' -butylidenebis (6-tert-butyl-m-cresol); 4,4' -thiobis (6-tert-butyl-m-cresol); 4,4' -dihydroxydiphenyl-cyclohexane; alkylating bisphenol; styrol; 2, 6-di-tert-butyl-4-methylphenol; n-octadecyl-3- (3 ',5' -di-tert-butyl-4 ' -hydroxyphenyl) propionate; 2,2' -methylenebis (4-methyl-6-tert-butylphenol); 4,4' -thiobis (3-methyl-6-tert-butylphenyl); 4,4' -butylidenebis (3-methyl-6-tert-butylphenol); stearoyl- β - (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate; 1, 3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane; 1,3, 5-trimethyl-2, 4, 6-tris (3, 5-di-tert-butyl-4-hydroxybenzyl) benzene; tetrakis [ methylene-3- (3 ',5' -di-tert-butyl-4 ' -hydroxyphenyl) propionate ] methane; stearoyl 3, 5-di-tert-butyl-4-hydroxy phenylpropionate; etc., and mixtures thereof.

In particular toSuitable compounds are compounds of the formula (VI), for example tris (3, 5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, which is available under the trade name3114 are available.

Another suitable antioxidant is a phosphite antioxidant. When used, phosphite antioxidants are typically present in an amount of about 0.02 to about 2 weight percent, in some embodiments about 0.04 to about 1 weight percent, and in some embodiments, about 0.1 to about 0.6 weight percent, based on the polymer composition. Phosphite antioxidants may include a variety of different compounds such as aryl monophosphites, aryl diphosphites, and the like, as well as mixtures thereof. For example, aryl bisphosphites of the following formula (IX) may be used:

wherein,,

R ₁ 、R ₂ 、R ₃ 、R ₄ 、R ₅ 、R ₆ 、R ₇ 、R ₈ 、R ₉ and R is ₁₀ Independently selected from hydrogen, C ₁ To C ₁₀ Alkyl and C ₃ To C ₃₀ Branched alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, or tert-butyl moieties.

Examples of such aryl bisphosphite compounds include, for example, bis (2, 4-dicumylphenyl) pentaerythritol bisphosphite (which may be used asS-9228 is commercially available) and bis (2, 4-di-tert-butylphenyl) pentaerythritol diphosphite (which is available as +. >626 commercially available). Likewise, suitable aryl monophosphites may include tris (2, 4-di-tert-butylphenyl) phosphiteAcid esters (can be regarded as->168 commercially available); bis (2, 4-di-tert-butyl-6-methylphenyl) phosphite ethyl ester (may be used as +.>38 commercially available); etc.

Another suitable antioxidant is a thioester antioxidant. When used, the thioester antioxidant is also typically present in an amount of from about 0.04 to about 4 wt.%, in some embodiments from about 0.08 to about 2 wt.%, and in some embodiments, from about 0.2 to about 1.2 wt.%, based on the polymer composition. Particularly suitable thioester antioxidants for use in the present invention are thiocarboxylic esters, such as those having the general structure:

R ₁₁ -O(O)(CH ₂ )x-S-(CH ₂ ) _y (O)O-R ₁₂

wherein,,

x and y are independently 1 to 10, in some embodiments 1 to 6, and in some embodiments 2 to 4 (e.g.,

2)；

R ₁₁ and R is ₁₂ Independently selected from linear or branched C ₆ To C ₃₀ Alkyl, in some embodiments selected from C ₁₀ To C ₂₄ Alkyl, and in some embodiments, is selected from C ₁₂ To C ₂₀ Alkyl groups such as lauryl, stearyl, octyl, hexyl, decyl, dodecyl, oleyl, and the like.

Specific examples of suitable thiocarboxylic esters may include, for example, distearyl thiodipropionate (as a solvent PS 800 is commercially available), dilauryl thiodipropionate (as +.>PS 802 commercially available), di-2-ethylhexyl-sulfurAnd thiodipropionates, diisodecyl thiodipropionate, and the like.

In particularly suitable embodiments of the present invention, a combination of antioxidants may be used to help provide a synergistic effect on the properties of the composition. For example, in one embodiment, the stabilizer system may use a combination of at least one hindered antioxidant, phosphite antioxidant, and thioester antioxidant. When used, the weight ratio of phosphite antioxidant to hindered phenol antioxidant may be in the range of about 1:1 to about 5:1, in some embodiments about 1:1 to about 4:1, and in some embodiments, about 1.5:1 to about 3:1 (e.g., about 2:1). The weight ratio of thioester stabilizer to phosphite antioxidant is also typically from about 1:1 to about 5:1, in some embodiments from about 1:1 to about 4:1, and in some embodiments, from about 1.5:1 to about 5:1 about 3:1 (e.g., about 2:1). Likewise, the weight ratio of thioester antioxidant to hindered phenol antioxidant is also typically from about 2:1 to about 10:1, in some embodiments from about 2:1 to about 8:1, and in some embodiments, from about 3:1 to about 6:1 (e.g., about 4:1). Within these selected ratios, it is believed that the compositions are capable of achieving a unique ability to remain stable even after exposure to high temperatures and/or ultraviolet light.

The polymer composition may also contain one or more UV stabilizers. Suitable UV stabilizers may include, for example, benzophenone (e.g., (2-hydroxy-4- (octyloxy) phenyl), methanone @, and81 Benzotriazole (e.g., 2- (2-hydroxy-3, 5-di-alpha-cumylphenyl) -2H-benzotriazole ()>234 2- (2-hydroxy-5-tert-octylphenyl) -2H-benzotriazole (+.>329 2- (2-hydroxy-3-alpha-cumyl-5-tert-octylphenyl) -2H-benzotriazole (+.>928 (2, 4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -s-triazine (-/-), etc.)>1577 A) sterically hindered amine (e.g. bis (2, 6-tetramethyl-4-piperidinyl) sebacate (-)>770 Dimethyl succinate and 1- (2-hydroxyethyl) -4-hydroxy-2, 6-tetramethyl-4-piperidine (>622 And the like), and mixtures thereof. Benzophenone is particularly useful in polymer compositions. When used, such UV stabilizers typically comprise from about 0.05% to about 2%, in some embodiments from about 0.1% to about 1.5%, and in some embodiments, from about 0.2% to about 1.0% by weight of the composition.

D. Other components

In addition to the above components, the polymer matrix may also contain a variety of other components. Examples of such optional components may include, for example, EMI fillers, compatibilizers, particulate fillers, lubricants, colorants, flow modifiers, pigments, and other materials added to enhance performance and processability. For example, when EMI shielding performance is desired, EMI fillers may be used. EMI fillers are typically formed from electrically conductive materials that can provide a desired degree of electromagnetic interference shielding. In certain embodiments, for example, the material comprises a metal, such as stainless steel, aluminum, zinc, iron, copper, silver, nickel, gold, chromium, and the like, as well as alloys or mixtures thereof. EMI fillers can also take a variety of different forms, such as particles (e.g., iron powder), flakes (e.g., aluminum flakes, stainless steel flakes, etc.), or fibers. Particularly suitable EMI fillers are fibers comprising metal. In such embodiments, the fibers may be formed primarily of metal (e.g., stainless steel fibers), or the fibers may be formed of a core material coated with metal. When a metallic coating is employed, the core material may be formed of a material that is conductive or insulating in nature. For example, the core material may be formed of carbon, glass, or a polymer. An example of such a fiber is nickel plated carbon fiber.

Compatibilizers may also be used to enhance the degree of adhesion between the long fibers and the polymer matrix. When used, such compatibilizers typically constitute from about 0.1 to about 15, in some embodiments from about 0.5 to about 10, and in some embodiments, from about 1 to about 5, percent by weight of the polymer composition. In certain embodiments, the compatibilizer may be a polyolefin compatibilizer comprising a polyolefin modified with polar functional groups. The polyolefin may be an olefin homopolymer (e.g., polypropylene) or copolymer (e.g., ethylene copolymer, propylene copolymer, etc.). The functional groups may be grafted onto the polyolefin backbone or incorporated as a monomer component of a polymer (e.g., a block or random copolymer), or the like. Particularly suitable functional groups include maleic anhydride, maleic acid, fumaric acid, maleimide, maleic hydrazide, reaction products of maleic anhydride with diamines, dichloromaleic anhydride, maleic acid amide, and the like.

Regardless of the particular components used, the raw materials (e.g., thermoplastic polymers, flame retardants, stabilizers, compatibilizers, etc.) are typically melt blended together to form a polymer matrix prior to reinforcement with long fibers. The raw materials may be supplied to the melt mixing device for dispersing the mixed materials simultaneously or sequentially. Batch and/or continuous melt blending techniques may be employed. For example, a mixer/kneader, a Banbury mixer, a Farrel continuous mixer, a single screw extruder, a twin screw extruder, a roll mill, or the like may be used to mix the materials. One particularly suitable melt blending device is a co-rotating twin screw extruder (e.g., a ZSK-30 twin screw extruder, available from Werner & Pfleiderer Corporation of Ramsey, N.J.). Such an extruder may include a feed port and a vent port and provide high intensity distribution and dispersive mixing. For example, the propylene polymer may be fed to the feed throat of a twin screw extruder and melted. Thereafter, the stabilizer may be injected into the polymer melt. Alternatively, the stabilizer may be fed separately into the extruder at different points along its length. Regardless of the particular melt blending technique selected, the materials are blended under high shear/pressure and heat to ensure thorough mixing. For example, melt blending may occur at a temperature of about 150 ℃ to about 300 ℃, in some embodiments about 155 ℃ to about 250 ℃, and in some embodiments, about 160 ℃ to about 220 ℃.

As noted above, certain embodiments of the present invention contemplate the use of polymer blends (e.g., propylene homopolymers and/or propylene/alpha-olefin copolymers) in the polymer matrix. In such embodiments, each polymer used in the blend may be melt blended in the manner described above. However, in still other embodiments, it may be desirable to melt blend a first polymer (e.g., a propylene polymer) to form a concentrate, which is then reinforced with long fibers to form a precursor composition in the manner described below. The precursor composition can then be blended (e.g., dry blended) with a second polymer (e.g., a propylene polymer) to form a polymer composition having the desired properties. It will also be appreciated that additional polymer may also be added before and/or during reinforcement of the polymer matrix with long fibers.

II. Long fibers

To form the fiber reinforced compositions of the present invention, long fibers are typically embedded in a polymer matrix. The long fibers may, for example, comprise from about 5% to about 50%, in some embodiments from about 10% to about 40%, and in some embodiments, from about 15% to 35% by weight based on the composition. Also, the polymer matrix typically comprises from about 50 wt% to about 95 wt%, in some embodiments from about 60 wt% to about 90 wt%, and in some embodiments, from about 65 wt% to about 85 wt%, based on the composition.

The term "long fibers" generally refers to fibers, filaments, yarns, or rovings that are discontinuous and have a length of from about 1 to about 25 millimeters, in some embodiments from about 1.5 to about 20 millimeters, in some embodiments from about 2 to about 15 millimeters, and in some embodiments, from about 3 to about 12 millimeters. Even after forming the molded part (e.g., injection molding), a substantial portion of the fibers may remain relatively long. That is, the median length (D50) of the fibers in the composition may be about 1 millimeter or greater, in some embodiments about 1.5 millimeters or greater, in some embodiments about 2.0 millimeters or greater, and in some embodiments, about 2.5 millimeters to about 8 millimeters. Regardless of their length, the nominal diameter of the fibers (e.g., the diameter of the fibers within the roving) can be selectively controlled to help improve the surface appearance of the resulting polymer composition. More specifically, the nominal diameter of the fibers may be in the range of about 20 to about 40 microns, in some embodiments about 20 to about 30 microns, and in some embodiments, about 21 to about 26 microns. Within this range, the tendency of the fibers to "cake" on the surface of the molded part is reduced, which results in the color and surface appearance of the part being primarily due to the polymer matrix. In addition to providing improved aesthetic consistency, it also allows better color retention after exposure to ultraviolet light, as the stabilizer system can be more easily used in the polymer matrix. Of course, it should be understood that other nominal diameters may be employed, such as those of about 1 to about 20 microns, in some embodiments about 8 to about 19 microns, and in some embodiments, about 10 to about 18 microns.

The fibers may be formed from any conventional material known in the art, such as metal fibers; glass fibers (e.g., E-glass, A-glass, C-glass, D-glass, AR-glass, R-glass, S1-glass, S2-glass), carbon fibers (e.g., graphite), boron fibers, ceramic fibers (e.g., alumina or silica), aramid fibers (e.g., silica) Synthetic organic fibers (e.g., polyamides, polyethylene, para-phenylene, terephthalamide, polyethylene terephthalate, and polyphenylene sulfide), metal fibers (e.g., stainless steel fibers) as described above, and various other natural or synthetic inorganic or organic fiber materials known for reinforcing thermoplastic compositions. Glass fibers, particularly S-glass fibers, are particularly desirable. The fibers may be twisted or straight. The fibers may be in the form of rovings (e.g., bundles) comprising a single fiber type or different types of fibers, if desired. The different fibers may be contained in separate rovings, or alternatively, eachThe root roving may contain different fiber types. For example, in one embodiment, some rovings may comprise carbon fibers, while other rovings may comprise glass fibers. The number of fibers contained in each roving may be constant or may vary from roving to roving. Typically, the roving may comprise from about 1000 fibers to about 50000 individual fibers, and in some embodiments, from about 2000 to about 40000 fibers. / >

The fibers may generally be incorporated into the polymer matrix using any of a number of different techniques. The long fibers may be randomly distributed in the polymer matrix or alternatively in an aligned manner. For example, in one embodiment, the continuous fibers may be initially impregnated into a polymer matrix to form strands, which are subsequently cooled and then cut into pellets such that the resulting fibers have the desired length of long fibers. In such embodiments, the polymer matrix and continuous fibers (e.g., rovings) are typically pultruded through an impregnation die to achieve the desired contact between the fibers and the polymer. Pultrusion can also help ensure that the fibers are spaced apart and aligned in the same or substantially similar direction, e.g., longitudinal direction (e.g., length) parallel to the pellet's major axis, which further enhances mechanical properties. Referring to fig. 1, for example, one embodiment of a pultrusion process 10 is shown wherein a polymer matrix is supplied from an extruder 13 to an impregnation die 11 while continuous fibers 12 are pulled through die 11 via a pultrusion device 18 to create a composite structure 14. Typical pultrusion devices may include, for example, crawler-type pultrusions and reciprocating pultrusions. Although optional, the composite structure 14 may also be pulled through a coating die 15 connected to an extruder 16 through which coating resin is applied to form a coating structure 17. As shown in fig. 1, the coating structure 17 is then pulled through a pulling assembly 18 and supplied to a pelletizer 19, which pelletizer 19 cuts the structure 17 to the desired size for forming the long fiber reinforced composition.

The nature of the impregnation die used in the pultrusion process can be selectively altered to help achieve good contact between the polymer matrix and the long fibers. Examples of suitable dip mold systems are described in detail in the 32,772 reissue patent to Hawley, the 9,233,486 reissue patent to Regan et al, and the 9,278,472 reissue patent to easep et al. For example, referring to FIG. 2, one embodiment of such a suitable impregnation die 11 is shown. As shown, the polymer matrix 127 may be supplied to the impregnation die 11 by an extruder (not shown). More specifically, the polymer matrix 127 may exit the extruder through barrel flange 128 and enter a die flange 132 of die 11. The mold 11 includes an upper mold half 134 that mates with a lower mold half 136. Continuous fibers 142 (e.g., rovings) are supplied from a spool 144 through a feed port 138 to the upper mold half 134 of the mold 11. Similarly, continuous fibers 146 are also supplied from reel 148 through feed port 140. The substrate 127 is heated within the mold halves 134 and 136 by a heater 133 mounted in the upper mold half 134 and/or the lower mold half 136. The mold is typically operated at a temperature sufficient to cause the thermoplastic polymer to melt and impregnate. Typically, the mold is operated at a temperature above the melting temperature of the polymer matrix. When treated in this manner, continuous fibers 142 and 146 become embedded in matrix 127. The mixture is then pulled through the impregnation die 11 to produce the fiber reinforced composition 152. The pressure sensor 137 may also detect the pressure near the impregnation die 11, if necessary, to allow the extrusion rate to be controlled by controlling the rotational speed of the screw shaft or the feed rate (feedrate) of the feeder.

Within the impregnation die, it is generally desirable that the fibers contact a series of impingement zones. In these areas, the polymer melt may flow laterally through the fibers to create shear and pressure forces, thereby significantly increasing the degree of impregnation. This is particularly useful when forming a composite from a high fiber content ribbon. Typically, the die will contain at least 2, in some embodiments at least 3, and in some embodiments 4 to 50 impingement zones per roving to produce a sufficient degree of shear and pressure. Although their specific form may vary, the impact zone typically has a curved surface, such as a curved blade, bar, or the like. The impact zone is also typically made of a metallic material.

Fig. 2 shows an enlarged schematic view of a portion of an impregnation die 11, the impregnation die 11 comprising a plurality of impingement zones in the form of vanes 182. It should be understood that the present invention may be practiced using multiple feed ports, which may optionally be coaxial with the machine direction. The number of feed ports used may vary with the number of fibers processed in the mold at one time, and the feed ports may be mounted in either the upper mold half 134 or the lower mold half 136. The feed port 138 includes a sleeve 170 mounted in the upper mold half 134. The feed port 138 is slidably mounted in a sleeve 170. The feed port 138 is divided into at least two sections, as shown by sections 172 and 174. The feed port 138 has a bore 176 extending longitudinally therethrough. The aperture 176 may be shaped as a right cylindrical cone opening away from the upper mold half 134. Fibers 142 pass through apertures 176 and into a passageway 180 between upper mold half 134 and lower mold half 136. A series of vanes 182 are also formed in the upper and lower mold halves 134, 136 such that the channel 210 adopts a convoluted path. The vanes 182 move the fibers 142 and 146 past at least one of the vanes such that the polymer matrix within the channel 180 is in substantial contact with each fiber. In this way, adequate contact between the molten polymer and fibers 142 and 146 is ensured.

To further facilitate impregnation, the fibers may also be held under tension while present in the impregnation die. The tension may be, for example, in the range of about 5 to about 300 newtons per bundle of fibers, in some embodiments about 50 to about 250 newtons per bundle of fibers, and in some embodiments, about 100 to about 200 newtons per bundle of fibers. In addition, the fibers may also pass through the impingement zone in a tortuous path to enhance shear forces. For example, in the embodiment shown in FIG. 2, the fibers traverse the impingement zone in a sinusoidal path. The angle at which the roving traverses from one impact zone to another is typically high enough to enhance shear, but not so high as to cause excessive forces that would damage the fibers. Thus, for example, the angle may be in the range of from about 1 ° to about 30 °, and in some embodiments, from about 5 ° to about 25 °.

The impregnation die shown and described above is but one of the various possible configurations that can be used with the present invention. In alternative embodiments, for example, the fibers may be introduced into a crosshead die that is positioned at an angle relative to the flow direction of the polymer melt. As the fibers move through the crosshead die and reach the point where the polymer exits the extruder barrel, the polymer is forced into contact with the fibers. It should also be appreciated that any other extruder design may be employed, such as a twin screw extruder. Still further, other components may optionally be used to aid in the impregnation of the fibers. For example, in some embodiments a "gas jet" assembly may be used to help spread (spread) bundles or bundles of individual fibers uniformly across the entire width of the combined bundle (which may each contain up to 24000 fibers). This helps to achieve an even distribution of the strength properties in the strip. Such an assembly may include a supply of compressed air or another gas that impinges on the moving fiber bundle through the outlet port in a generally vertical manner. The spread fiber bundles may then be introduced into a mold for impregnation, for example as described above.

Fiber reinforced polymer compositions are generally useful for forming molded parts using a variety of different techniques. Suitable techniques may include, for example, injection molding, low pressure injection molding, extrusion compression molding, gas injection molding, foam injection molding, low pressure gas injection molding, low pressure foam injection molding, gas extrusion compression molding, foam extrusion compression molding, extrusion molding, foam extrusion molding, compression molding, foam compression molding, gas compression molding, and the like. For example, an injection molding system including a mold into which the fiber-reinforced composition may be injected may be used. The time within the syringe can be controlled and optimized so that the polymer matrix is not pre-cured. When the cycle time is reached and the barrel is full for discharge, a piston may be used to inject the composition into the mold cavity. Compression molding systems may also be used. As with injection molding, the molding of the fiber reinforced composition into the desired article is also performed in a mold. The composition may be placed into the stamper using any known technique, such as picking by an automated robotic arm. The temperature of the mold may be maintained at or above the solidification temperature of the polymer matrix for a desired period of time to allow solidification. The molded product may then be cured by subjecting the molded product to a temperature below the melting temperature. The resulting product may be demolded. The cycle time of each molding process can be adjusted to accommodate the polymer matrix to achieve adequate bonding and to increase the productivity of the overall process. Because of the unique properties of the fiber reinforced composition, relatively thin molded parts (e.g., injection molded parts) can be easily formed therefrom. For example, such components may have a thickness of about 10 millimeters or less, in some embodiments about 8 millimeters or less, in some embodiments about 6 millimeters or less, in some embodiments about 0.4 to about 5 millimeters, and in some embodiments, about 0.8 to about 4 millimeters (e.g., 0.8, 1.2, or 3 millimeters).

II electronic module

As described above, the polymer composition can be used in electronic modules. The module typically includes a housing for housing one or more electronic components (e.g., printed circuit boards, antenna elements, radio frequency sensing elements, sensors, optical sensing and/or transmission elements (e.g., optical fibers), cameras, global positioning devices, etc.). For example, the housing may include a base including a sidewall extending therefrom. The cover may also be supported on the side walls of the base to define an interior in which the electronic components are housed and protected from the external environment. Regardless of the specific configuration of the module, the polymer composition of the present invention may be used to form all or a portion of the housing and/or cover. In one embodiment, for example, the polymer compositions of the present invention can be used to form the base and sidewalls of a housing. In such embodiments, the cover may be formed from the polymer composition of the present invention or from a different material, such as a metal component (e.g., an aluminum plate). It is noted that one benefit of the present invention is that the polymer composition has a linear coefficient of thermal expansion similar to that of typical metal components used in electronic modules. For example, the linear thermal expansion coefficient of the polymer composition may be in the range of about 10 μm/m ℃ to about 35 μm/m ℃, in some embodiments in the range of about 12 μm/m ℃ to about 32 μm/m ℃, and in some embodiments, from 15 μm/m ℃ to about 30 μm/m ℃, as measured in the flow direction (parallel) according to ISO 11359-2:1999. Further, the ratio of the linear thermal expansion coefficient of the polymer composition to the linear thermal expansion coefficient of the metal component may be from about 0.5 to about 1.5, in some embodiments from about 0.6 to about 1.2, and in some embodiments, from about 0.6 to about 1.0. For example, aluminum has a linear thermal expansion coefficient of about 21 to 24 μm/mdeg.C.

Referring to fig. 3, for example, one particular embodiment of an electronic module 100 is shown that may incorporate the polymer composition of the present invention. The electronic module 100 includes a housing 102, the housing 102 including a sidewall 132 extending from a base 114. The housing 102 may also contain a shroud 116 that may house electrical connectors (not shown), if desired. In any event, a printed circuit board ("PCB") is housed inside the module 100 and attached to the housing 102. More specifically, the circuit board 104 includes an aperture 122 that aligns with the post 110 located on the housing 102 and receives the post 110. The circuit board 104 has a first surface 118, and circuitry 121 is provided on the first surface 118 to enable radio frequency operation of the module 100. For example, RF circuitry 121 may include one or more antenna elements 120a and 120b. The circuit board 104 also has a second surface 119 opposite the first surface 118, and may optionally contain other electrical components, such as components (e.g., digital signal processors, semiconductor memory, input/output interface devices, etc.) that enable digital electronic operation of the module 100. Alternatively, such components may be provided on additional printed circuit boards. A cover 108 may also be employed that is disposed over the circuit board 104 and attached to the housing 102 (e.g., side walls) by known techniques, such as by soldering, adhesive, etc., to seal the electrical components inside. As described above, the polymer composition may be used to form all or a portion of the cover 108 and/or the housing 102.

Electronic modules may be used in a variety of applications. For example, the electronic module may be used in a motor vehicle (e.g., an electric vehicle). For example, when used in automotive applications, the electronic module may be used to sense the positioning of a vehicle relative to one or more three-dimensional objects. In this regard, the module may include a radio frequency sensing assembly, a light detection or optical assembly, a camera, an antenna element, and the like, as well as combinations thereof. For example, the module may be a radio detection and ranging ("radar") module, a light detection and ranging ("lidar") module, a camera module, a global positioning module, etc., or may be an integrated module that combines two or more of these components. Such modules may thus be employed to house one or more types of electronic components (e.g., printed circuit boards, antenna elements, radio frequency sensing devices, sensors, light sensing and/or transmission elements (e.g., optical fibers), cameras, global positioning devices, etc.). For example, in one embodiment, a lidar module may be formed that includes a fiber optic assembly for receiving and transmitting pulses of light that are received inside a housing/cover assembly in a manner similar to the embodiments described above. Similarly, radar modules typically include one or more printed circuit boards having electrical components dedicated to processing Radio Frequency (RF) radar signals, digital signal processing tasks, and the like.

The electronic module may also be used in a 5G system. For example, the electronic module may be an antenna module, such as a macrocell (base station), a small cell, a microcell, or a repeater (femtocell), or the like. In this context, "5G" generally refers to high-speed data communication via radio frequency signals. The 5G network and system are capable of transmitting data at a much faster rate than the previous data communication standards (e.g. "4G", "LTE"). Various standards and specifications have been promulgated, quantifying the requirements of 5G communications. For example, the International Telecommunications Union (ITU) promulgated international mobile communications 2020 ("IMT-2020") standards in 2015. The IMT-2020 standard specifies various data transmission standards for 5G (e.g., downlink and uplink data rates, delays, etc.). The IMT-2020 standard defines uplink and downlink peak data rates as the lowest data rates that the 5G system must support for uploading and downloading data. The IMT-2020 standard specifies a downstream peak data rate of 20Gbit/s and an upstream peak data rate of 10Gbit/s. As another example, the third generation partnership project (3 GPP) recently released a new standard of 5G, called "5G NR". The 3GPP release "release 15" in 2018, defining the "first phase" of 5G NR standardization. The 3GPP defines the 5G frequency band generally as "frequency range 1" (FR 1), including frequencies below 6GHz, and "frequency range 2" (FR 2) as the 20-60GHz frequency band. However, as used herein, "5G frequency" may refer to systems using frequencies greater than 60GHz, e.g., ranging up to 80GHz, up to 150GHz, and up to 300GHz. As used herein, "5G frequency" may refer to a frequency of about 1.8GHz or higher, in some embodiments about 2.0GHz or higher, in some embodiments about 3.0GHz or higher, in some embodiments about 3GHz to about 300GHz, or higher, in some embodiments about 4GHz to about 80GHz, in some embodiments about 5GHz to about 80GHz, in some embodiments about 20GHz to about 80GHz, and in some embodiments about 28GHz to about 60GHz.

A 5G antenna system typically employs high frequency antennas and antenna arrays for 5G components, such as macro cells (base stations), small cells, micro cells, or repeaters (femtocells), etc., and/or other suitable components of a 5G system. The antenna elements/arrays and systems may meet or conform to the "5G" standard according to standards promulgated by 3GPP, such as release 15 (2018) and/or IMT-2020 standards. To achieve such high-speed data communications at high frequencies, antenna elements and arrays typically employ small feature sizes/pitches (e.g., fine pitch technology) that can improve antenna performance. For example, the feature size (spacing between antenna elements, width of antenna elements), etc., typically depends on the wavelength ("λ") of the desired transmission and/or reception radio frequency propagating through the substrate on which the antenna elements are formed (e.g., nλ/4, where n is an integer). Furthermore, beamforming and/or beam steering may be employed to facilitate reception and transmission across multiple frequency ranges or channels (e.g., multiple Input Multiple Output (MIMO), massive MIMO). The high frequency 5G antenna element may have a variety of configurations. For example, the 5G antenna element may be or include a coplanar waveguide element, a patch array (e.g., a grid patch array), other suitable 5G antenna configuration. The antenna elements may be configured to provide MIMO, massive MIMO functionality, beam steering, and the like. As used herein, "massive" MIMO functionality generally refers to providing a large number of transmit and receive channels, e.g., 8 transmit (Tx) and 8 receive (Rx) channels (abbreviated as 8x 8), using an antenna array. Massive MIMO functionality may be provided by dimensions of 8x8, 12x12, 16x16, 32x32, 64x64 or greater.

The antenna element may be manufactured using a variety of manufacturing techniques. As one example, the antenna elements and/or associated elements (e.g., ground elements, feed lines, etc.) may employ fine pitch technology. Fine pitch technology generally refers to small or fine pitches between their elements or leads. For example, the feature size and/or spacing between antenna elements (or between antenna elements and ground plane) may be about 1500 microns or less, in some embodiments 1250 microns or less, in some embodiments 750 microns or less (e.g., center-to-center spacing of 1.5 millimeters or less), 650 microns or less, in some embodiments 550 microns or less, in some embodiments 450 microns or less, in some embodiments 350 microns or less, in some embodiments 250 microns or less, in some embodiments 150 microns or less, in some embodiments 100 microns or less, and in some embodiments 50 microns or less. However, it should be understood that smaller and/or larger feature sizes and/or pitches may also be employed. Due to such small feature sizes, the antenna configuration and/or array may be implemented with a large number of antenna elements in a small footprint. For example, the antenna array may have an average antenna element concentration of greater than 1000 antenna elements per square centimeter, in some embodiments greater than 2000 antenna elements per square centimeter, in some embodiments greater than 3000 antenna elements per square centimeter, in some embodiments greater than 4,000 antenna elements per square centimeter, in some embodiments greater than 6000 antenna elements per square centimeter, and in some embodiments greater than about 8000 antenna elements per square centimeter. This compact arrangement of antenna elements may provide a greater number of channels per unit area of antenna area for MIMO functionality. For example, the number of channels may correspond to (e.g., be equal to or proportional to) the number of antenna elements.

Referring to fig. 4, for example, 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 relays 108 (e.g., "femtocells"), and/or other suitable antenna components for 5G antenna system 100. The relay station 104 may be configured to facilitate communication of the user computing device 106 and/or other relay stations 104 with the base station 102 by relaying or "forwarding" signals between the base station 102 and the user computing device 106 and/or relay stations 104. Base station 102 may include a MIMO antenna array 110 configured to receive and/or transmit radio frequency signals 112 with relay station 104, wi-Fi relay 108, and/or directly with user computing device 106. The user computing device 306 need not be limited by the present invention and includes devices such as 5G smartphones. MIMO antenna array 110 may employ beam steering to focus or steer radio frequency signals 112 with respect to relay station 104. For example, the MIMO antenna array 110 may be configured to adjust an elevation angle 114 relative to the X-Y plane and/or a heading angle 116 defined in the Z-Y plane and relative to the Z-direction. Similarly, one or more of the relay station 104, the user computing device 106, the Wi-Fi repeater 108 may employ beam steering to improve reception and/or transmission capabilities with respect to the MIMO antenna array 110 by directionally tuning the sensitivity and/or power transmission of the device 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 and/or relative azimuth of the respective device).

The invention will be better understood with reference to the following examples.

Test method

Melt flow index: the melt flow index of the polymer or polymer composition can be determined according to ISO 1133-1:2011 (technically equivalent to ASTMD 1238-13) at a load of 2.16kg and a temperature of 230 ℃.

Tensile modulus, tensile stress, and tensile elongation at break: tensile properties may be tested according to ISO test number 527-1:2019 (technically equivalent to ASTM D638-14). Modulus and strength measurements can be made on dog bone test strip samples of 170/190mm in length, 4mm in thickness and 10mm in width. The test temperature may be-30deg.C, 23deg.C or 80deg.C, and the test speed may be 1 or 5mm/min.

Flexural modulus, elongation at break at bend and flexural stress: flexural performance can be tested according to ISO test number 178:2019 (technically equivalent to ASTM D790-17). The test can be performed over a support span of 64 mm. The test can be performed in the central portion of an uncut ISO 3167 multipurpose bar. The test temperature may be-30deg.C, 23deg.C or 80deg.C, and the test speed may be 2mm/min.

Charpy impact Strength: the Charpy characteristics may be tested according to ISO test number ISO 179-1:2010) (technically equivalent to ASTM D256-10, method B). The test can be performed using a type 1 specimen size (80 mm in length, 10mm in width, and 4mm in thickness). A single tooth milling machine may be used to cut the sample from the center of the multipurpose bar. The test temperature may be-30 ℃, 23 ℃ or 80 ℃.

Load deflection temperature ("DTUL"): flexural deformation at load temperature can be determined according to ISO test number 75-2:2013 (technically equivalent to ASTM D648-07). More specifically, an edge three point bend test can be performed on a test strip sample having a length of 80mm, a width of 10mm, and a thickness of 4mm, with a specified load (maximum external fiber stress) of 1.8 megapascals. The sample may be placed in a silicone oil bath and the temperature raised at a rate of 2 c per minute until it deforms by 0.25 mm (0.32 mm for ISO test No. 75-2:2013).

Coefficient of linear thermal expansion ("CLTE"): the linear thermal expansion coefficient can be determined in the flow and/or transverse direction according to ISO 11359.

Dielectric constant ("Dk") and dissipation factor ("Df"): the dielectric constant (or relative static permittivity) and dissipation factor (or loss tangent) were determined according to IPC 650 test method, clause 2.5.5.13 (1/07) at 2GHz frequency. According to this method, the in-plane dielectric constant and dissipation factor can be determined using split cylindrical resonators. The test specimen had a thickness of 8.175 mm, a width of 70 mm and a length of 70 mm.

Limiting oxygen index: limiting oxygen index ("LOI") can be determined by ISO 4589:2017 (technically equivalent to ASTM D2863-19). The LOI is the lowest oxygen concentration in the oxygen and nitrogen flowing mixture that just supports combustion. More specifically, the sample may be placed vertically in a transparent test column and a mixture of oxygen and nitrogen may be forced upward through the column. The sample may be ignited at the top. The oxygen concentration may be adjusted until the sample just supports combustion. The reported concentrations are the volume percent of oxygen that the sample just supports combustion.

UL94: the sample was supported vertically and a flame was applied to the bottom of the sample. The flame was applied for ten (10) seconds and then removed until the flame stopped, at which time the flame was applied again for another ten (10) seconds and then removed. Two (2) sets of five (5) samples were tested. The sample size was 125 mm long, 13 mm wide and 3 mm thick. Both groups were conditioned before and after aging. For the unaged test, each thickness was tested after conditioning at 23 ℃ and 50% relative humidity for 48 hours. For the aging test, five (5) samples of each thickness were tested after conditioning at 70 ℃ for 7 days.

Example 1

The resulting sample contained about 45% by weight of propylene homopolymer (melt flow index 65g/10min, density 0.90g/cm ³ ) 35 wt.% of a flame retardant masterbatch, 20 wt.% of a continuous glass fiber roving (2400 tex, filament diameter 16 μm), less than 5 wt.% of a coupling agent (maleic anhydride grafted olefin polymer), and less than 2 wt.% of a thermal/UV stabilizer. The flame retardant masterbatch contains 40 wt% polypropylene and 60 wt% of a halogen-free flame retardant system comprising a phosphorus-based flame retardant as described above. The samples were melt processed in a single screw extruder (90 mm) with a melt temperature of 250 ℃, a die temperature of 250 ℃, a zone temperature in the range 160 ℃ to 320 ℃ and a screw speed of 160 revolutions per minute.

Example 2

The resulting sample contained about 50% by weight of propylene homopolymer (melt flow index 65g/10min, density 0.90g/cm ³ ) 30% by weight of the flame-retardant masterbatch as described in example 1, 20% by weight of continuous glass fiber roving (2400 tex, filament diameter 16 μm), less than 5% by weight of coupling agent (maleic anhydride grafted olefin polymer), and less than 2% by weight of thermal/UV stabilizer. The samples were melt processed in a single screw extruder (90 mm) with a melt temperature of 250 ℃, a die temperature of 250 ℃, a zone temperature in the range 160 ℃ to 320 ℃ and a screw speed of 160 revolutions per minute.

Example 3

The sample formed contained 80 wt% of a polycarbonate-acrylonitrile-flame retardant mixture (fromCreative scienceFR 3010) and 20% by weight of continuous glass fiber rovings (2400 tex, filament diameter 16 μm). The samples were melt processed in a single screw extruder (90 mm) with a melt temperature of 310 ℃, a die temperature of 310 ℃, a zone temperature in the range 160 ℃ to 320 ℃ and a screw speed of 160 revolutions per minute.

Example 4

The resulting sample contained 70 wt% of a polycarbonate-acrylonitrile-flame retardant blend (from kefirFR 3010) and 30% by weight of continuous glass fiber rovings (2400 tex, filament diameter 16 μm). The samples were melt processed in a single screw extruder (90 mm) with a melt temperature of 310 ℃, a die temperature of 310 ℃, a zone temperature in the range 160 ℃ to 320 ℃ and a screw speed of 160 revolutions per minute.

The samples of examples 1-4 were tested for dielectric properties, mechanical properties and flame retardancy. The results are shown in the following table.

These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention. Further, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims.

Claims

1. An electronic module comprising a housing containing at least one electronic component, wherein the housing contains a fiber-reinforced polymer composition comprising a polymer matrix containing a thermoplastic polymerAnd a plurality of long reinforcing fibers distributed within the polymer matrix, wherein the polymer composition exhibits a dielectric constant of about 4 or less and a dissipation factor of about 0.01 or less at a frequency of 2GHz, and further wherein the polymer composition exhibits a dielectric constant of about 20kJ/m as measured according to ISO test No. 179-1:2010 at a temperature of about 23 °c ² Or higher charpy unnotched impact strength.

2. The electronic module of claim 1, wherein the polymer composition exhibits a limiting oxygen index of about 25 or greater as determined according to ISO 4589:2017.

3. The electronic module of claim 1, wherein the polymer composition exhibits a V0 or V1 rating according to UL 94.

4. The electronic module of claim 1, wherein the polymer composition exhibits a total burn time according to UL94 of about 250 seconds or less.

5. The electronic module of claim 1, wherein the polymer composition exhibits a flexural strength of about 100 to about 500MPa as determined according to ISO test No. 178:2019 at a temperature of about 23 ℃.

6. The electronic module of claim 1, wherein the polymer composition exhibits about 20kJ/m as measured according to ISO test No. 179-1:2010 at a temperature of about-40 °c ² Or higher charpy unnotched impact strength.

7. The electronic module of claim 1, wherein the polymer composition exhibits a tensile strength of about 50MPa or greater as determined according to ISO test number 527-1:2019 at a temperature of about 23 ℃.

8. The electronic module of claim 1, wherein the polymer composition exhibits a tensile strength of about 50MPa or greater as determined according to ISO test number 527-1:2019 at a temperature of about-40 ℃.

9. The electronic module of claim 1, wherein the thermoplastic polymer comprises a propylene polymer.

10. The electronic module of claim 1, wherein the thermoplastic polymer comprises an aromatic polycarbonate.

11. The electronic module of claim 10, wherein the polymer matrix further comprises an acrylonitrile-butadiene-styrene copolymer.

12. The electronic module of claim 1, wherein the polymer matrix comprises about 50% to about 95% by weight of the composition and the long reinforcing fibers comprise about 5% to about 50% by weight of the composition.

13. The electronic module of claim 1, wherein the polymer composition further comprises a flame retardant system.

14. The electronic module of claim 13, wherein the flame retardant system comprises at least one halogen-free organophosphorus flame retardant.

15. The electronic module of claim 14, wherein the organophosphorus flame retardant comprises a nitrogen-containing phosphate.

16. The electronic module of claim 15, wherein the phosphate comprises melamine phosphate, piperazine phosphate, or a combination thereof.

17. The electronic module of claim 14, wherein the organophosphorus flame retardant comprises a phosphate, a phosphonate, a phosphinate, a phosphonate amine, a phosphazene, or a combination thereof.

18. The electronic module of claim 14, wherein the organophosphorus flame retardant comprises about 50% to about 99.5% by weight of the flame retardant system.

19. The electronic module of claim 1, wherein the polymer composition further comprises a stabilizer system.

20. The electronic module of claim 19, wherein the stabilizer system comprises a hindered phenol antioxidant, a phosphite antioxidant, a thioester antioxidant, or a combination thereof.

21. The electronic module of claim 19, wherein the stabilizer system comprises a UV stabilizer.

22. The electronic module of claim 1, wherein the fibers comprise glass fibers.

23. The electronic module of claim 1, wherein the fibers are spaced apart and aligned in a substantially similar direction.

24. The electronic module of claim 1, wherein the polymer composition exhibits an electromagnetic shielding effectiveness of about 20 decibels or greater as measured according to AST MD4935-18 at a frequency of 2 GHz.

25. The electronic module of claim 1, wherein the housing comprises a base including side walls extending therefrom and an optional cover supported by the side walls.

26. The electronic module of claim 25, wherein the base, sidewall, cover, or combination thereof comprises the polymer composition.

27. The electronic module of claim 1, wherein the polymer composition is located proximate to a metal component.

28. The electronic module of claim 27, wherein a ratio of a coefficient of linear thermal expansion of the polymer composition to a coefficient of linear thermal expansion of the metal component is about 0.5 to about 1.5.

29. The electronic module of claim 27, wherein the metal component comprises aluminum.

30. The electronic module of claim 1, wherein the polymer composition exhibits a linear coefficient of thermal expansion of about 10 μιη/m ℃ to about 35 μιη/m ℃.

31. The electronic module of claim 1, wherein the electronic assembly comprises an antenna element configured to transmit and receive 5G radio frequency signals.

32. The electronic module of claim 31, wherein the module is a base station, a small cell, or a femto cell.

33. A 5G system comprising the electronic module of claim 32.

34. The electronic module of claim 1, wherein the electronic component comprises a radio frequency sensing element.

35. The electronic module of claim 33, wherein the module is a radar module.

36. The electronic module of claim 1, wherein the electronic assembly comprises a fiber optic assembly for receiving and transmitting pulses of light.

37. The electronic module of claim 36, wherein the electronic module is a lidar module.

38. The electronic module of claim 1, wherein the electronic component comprises a camera.