阅读说明：本技术 包含多模态介电填料的可熔融加工的热塑性复合材料 (Melt-processable thermoplastic composite material comprising a multimodal dielectric filler ) 是由 史蒂芬·奥康纳 穆拉利·塞瑟马达范 于 2019-03-20 设计创作，主要内容包括：在一个实施方案中,热塑性复合材料包含：热塑性聚合物；和具有多模态粒径分布的介电填料,其中多模态粒径分布的第一模态的峰是多模态粒径分布的第二模态的峰的至少七倍；以及流动改性剂。(In one embodiment, a thermoplastic composite comprises: a thermoplastic polymer; and a dielectric filler having a multi-modal particle size distribution, wherein a peak of a first mode of the multi-modal particle size distribution is at least seven times a peak of a second mode of the multi-modal particle size distribution; and a flow modifier.)

1. A melt-processable thermoplastic composite comprising:

a thermoplastic polymer;

a dielectric filler having a multi-modal particle size distribution; wherein the peak of the first mode of the multi-modal particle size distribution is at least seven times the peak of the second mode of the multi-modal particle size distribution; and

a flow modifier.

2. The melt-processable thermoplastic composite material of claim 1, wherein the thermoplastic composite material has a dielectric constant of greater than or equal to 5, preferably 10 to 20, at 500MHz to 10GHz, or a dielectric constant of 15 to 25 at 500MHz to 10 GHz; and a dielectric loss of less than or equal to 0.007 at 500MHz to 10 GHz.

3. The melt processable thermoplastic composite material of any one or more of the preceding claims, wherein the thermoplastic polymer comprises poly (aryl) ether ketone, polysulfone, poly (phenylene sulfide), poly (ether imide), poly (amide imide), fluoropolymer, polyolefin, or a combination comprising at least one of the foregoing.

4. The melt processable thermoplastic composite material of any one or more of the preceding claims, wherein the thermoplastic polymer comprises poly (ether ketone), polyethylene, poly (phenylene ether), cyclic olefin copolymer, or a combination comprising at least one of the foregoing.

5. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the thermoplastic composite comprises 10 to 90 volume percent, or 20 to 80 volume percent, or 20 to 70 volume percent, or 30 to 50 volume percent of the thermoplastic polymer, based on the total volume of the thermoplastic composite.

6. The melt-processable thermoplastic composite material of any one or more of the preceding claims, wherein the thermoplastic polymer comprises or consists of a liquid crystalline polymer.

7. The melt processable thermoplastic composite material of claim 6, wherein the liquid crystalline polymer comprises a liquid crystalline polyester.

8. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the dielectric filler comprises titanium dioxide, barium titanate, strontium titanate, silica, corundum, wollastonite, boron nitride, aluminum oxide, aluminum nitride, silicon carbide, beryllium oxide, magnesium oxide, silica, or a combination comprising at least one of the foregoing.

9. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the dielectric filler comprises at least one of titanium dioxide, silicon dioxide, or barium titanate.

10. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the dielectric filler comprises silica.

11. The melt processable thermoplastic composite material of any one or more of the preceding claims, wherein the dielectric filler comprises a first plurality of particles having a first average particle size and a second plurality of particles having a second average particle size; wherein the first average particle size corresponds to the peaks of the first mode and the second average particle size corresponds to the peaks of the second mode; and wherein the peak of the first mode of the multi-modal particle size distribution is from 10 to 20 times the peak of the second mode of the multi-modal particle size distribution.

12. The melt processable thermoplastic composite material of claim 11, wherein said first plurality of particles comprises silica and said second plurality of particles comprises titania.

13. The melt processable thermoplastic composite material of claim 11, wherein the first plurality of particles and the second plurality of particles comprise titanium dioxide.

14. The melt-processable thermoplastic composite of any one or more of the preceding claims, wherein the multi-modal particle size distribution is bi-modal or tri-modal.

15. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the peak of the first mode is from 1 micron to 10 microns and the peak of the second mode is from 0.01 micron to 1 micron.

16. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the thermoplastic composite comprises 10 to 90 volume percent, or 20 to 80 volume percent, or 30 to 80 volume percent, or 50 to 70 volume percent of the dielectric filler, based on the total weight of the thermoplastic composite.

17. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the flow modifier comprises a ceramic filler, a fluoropolymer, a silsesquioxane, or a combination comprising at least one of the foregoing.

18. The melt processable thermoplastic composite of any one or more of the preceding claims, wherein the flow modifier comprises boron nitride, a fluoropolymer, a trisilanolphenylsilsesquioxane, or a combination comprising at least one of the foregoing.

19. The melt processable thermoplastic composite material of any one or more of the preceding claims, wherein the flow modifier is present in an amount of less than or equal to 5 volume percent, or 0.5 to 2 volume percent, based on the total volume of the thermoplastic composite material.

20. An article comprising the melt-processable thermoplastic composite material according to any one or more of the preceding claims.

21. An article according to claim 20, wherein an electrically conductive layer is disposed on at least one side of the melt processable thermoplastic composite material.

22. The article of claim 20, wherein the article is an antenna, wherein the antenna is preferably a planar inverted-F antenna, a patch antenna, a dipole antenna, or a meander-line antenna.

23. The article of claim 20, wherein the article is a filament or powder for 3D printing.

24. A method of forming the article of any one of claims 20 to 24, comprising:

injecting the melt-processable thermoplastic composite material of any one or more of claims 1 to 19 in molten form into a mold; and

cooling the mold to form the article.

25. A method of forming the article of any one of claims 20 to 24, comprising:

melting the melt-processable thermoplastic composite of any one or more of claims 1 to 19 to form a molten thermoplastic composite; and

printing the article with an additive manufacturing system in a layer-by-layer manner.

26. A method of forming the melt processable thermoplastic composite material of any one of claims 1 to 19, comprising extruding the melt processable thermoplastic composite material.

Background

The present disclosure relates generally to melt-processable thermoplastic composites.

For any melt-processable thermoplastic composite material, there is a temperature-dependent critical shear rate above which the surface of the melt-processed material is rough, and below which the surface of the melt-processed material is smooth. The requirement for a smooth melt-processed material surface competes with the economic advantage of melt processing the composition at the fastest speed possible (e.g., at high shear rates). As the amount of dielectric filler in the thermoplastic composite increases, the critical shear rate decreases and the composition becomes increasingly difficult to melt process. Thus, it is extremely difficult to obtain melt-processable thermoplastic composites with increased amounts of dielectric filler, which ultimately limits several potential advantages of using ceramic fillers in thermoplastic composites, such as dielectric constant, coefficient of thermal expansion, and the like.

Accordingly, there remains a need in the art for high dielectric constant materials made from melt processable thermoplastic composites. It would be advantageous if the melt-processable thermoplastic composite material exhibited one or more of improved melt processability and improved mechanical properties.

Disclosure of Invention

Disclosed herein are thermoplastic composites and methods of making and using the same.

In one embodiment, a thermoplastic composite comprises: a thermoplastic polymer; and a dielectric filler having a multi-modal particle size distribution, wherein a peak of a first mode of the multi-modal particle size distribution is at least seven times a peak of a second mode of the multi-modal particle size distribution; and a flow modifier.

Methods of forming the thermoplastic composition may include injection molding, printing, and extrusion.

An article comprising a thermoplastic composite may include an antenna and a filament (filament).

The above features and advantages, and other features and advantages, are readily apparent from the following detailed description, the accompanying drawings, and the claims.

Drawings

The following figures are exemplary embodiments and are provided to illustrate the present disclosure. The drawings are illustrative of embodiments and are not intended to limit devices made in accordance with the present disclosure to the materials, conditions, or process parameters set forth herein.

FIG. 1 is a graphical illustration of the dielectric constant versus filler volume for example 7; and

FIG. 2 is a graphical illustration of the dielectric constant versus filler volume for example 8.

Detailed Description

Thermoplastic composites with high concentrations of dielectric fillers tend to be viscous even at high processing temperatures, e.g., above 300 degrees celsius (° c), and thus are very difficult to melt process. For example, thermoplastic composites containing greater than 40 volume percent (vol%) titanium dioxide are often difficult to injection mold, or even impossible to injection mold. It has been unexpectedly found that the viscosity of a thermoplastic composite can be reduced by merely exchanging a portion of the dielectric filler with a dielectric filler having a different particle size. This reduction in viscosity may ultimately allow the thermoplastic composite to be more easily injection molded and to have a smoother molding surface. In particular, it was found that thermoplastic composites comprising a thermoplastic polymer and a dielectric filler having a multimodal particle size distribution result in composites of lower viscosity; wherein the peak of the first mode of the multi-modal particle size distribution is at least seven times the peak of the second mode of the multi-modal particle size distribution.

Improved formability is advantageously achieved without causing a reduction in the dielectric properties of the thermoplastic composite. For example, the dielectric constant (also commonly referred to as the relative permittivity) of the thermoplastic composite at 23 ℃ may be greater than or equal to 5, or greater than or equal to 10, or 10 to 20, or 15 to 25 at 500MHz to 10GHz, which is otherwise typically obtained using only thermosetting polymers. Furthermore, it has surprisingly been found that thermoplastic composites comprising a multimodal distribution of dielectric fillers also result in an improvement of the mechanical properties. For example, a thermoplastic composite comprising 40 volume percent of a multi-modal dielectric filler can exhibit a ductile failure mode, while a corresponding thermoplastic composite comprising the same amount of a single-modal dielectric filler exhibits a brittle failure mode.

The thermoplastic composite may comprise a thermoplastic polymer. The thermoplastic polymer can include oligomers, polymers, ionomers, dendrimers, copolymers (e.g., graft copolymers, random copolymers, block copolymers (e.g., star block copolymers and random copolymers)), and combinations comprising at least one of the foregoing. The thermoplastic polymer may be semicrystalline or amorphous. The thermoplastic polymer can have a dielectric loss (also referred to as a dissipation factor) at a frequency of 500MHz to 100GHz or 500MHz to 10GHz at 23 ℃ of less than or equal to 0.007, or less than or equal to 0.006, or 0.0001 to 0.007. The thermoplastic polymer can have a heat distortion temperature as determined according to ASTM D648-18 at 1.8MPa of greater than or equal to 55 ℃, or from 55 ℃ to 250 ℃. The thermoplastic polymer can have a glass transition temperature of greater than or equal to 50 ℃ to 300 ℃, or 80 ℃ to 300 ℃, as determined according to ASTM E1545-11 (2016).

The thermoplastic composite may comprise 10 to 90, or 20 to 80, or 20 to 70, or 20 to 60, or 30 to 50 volume percent of the thermoplastic polymer, based on the total volume of the thermoplastic composite.

The thermoplastic polymer may include polycarbonate, polystyrene, poly (phenylene ether), polyimide (e.g., polyetherimide), polybutadiene, polyacrylonitrile, polymethacrylic acid (C)_1-12Alkyl) esters (e.g., Polymethylmethacrylate (PMMA)), polyesters (e.g., poly (ethylene terephthalate), poly (butylene terephthalate), polythioesters), polyolefins (e.g., polypropylene (PP), High Density Polyethylene (HDPE), Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE)), polyamides (e.g., polyamideimide), polyarylates, polysulfones (e.g., polyarylsulfone, polysulfonamide), poly (phenylene sulfide), poly (phenylene ether), polyethers (e.g., poly (ether ketone) (PEK), poly (ether ketone) (PEEK), Polyethersulfone (PES)), poly (acrylic acid), polyacetals, polybenzo-polyamides, and poly (arylene ether ketone) (PEEK), poly (arylene ether ketone) (PES), poly (arylene ether ketone) (Azoles (e.g., polybenzothiazole, polybenzothiazolothiazine), poly(s)Oxadiazoles, polypyrazinoquinoxalines, polyterepimimides, polyquinoxalines, polybenzimidazoles, polyhydroxyindoles, polyoxyisoindolines (e.g., polydioxoisoindolines), polytriazines, polypyridazines, polypiperazines, polypyridines, polypiperidines, polytriazoles, polypyrazoles, polypyrrolidines, polycarboboranes, polyoxabicyclononanes, polydibenzofurans, polyphthalides, polyacetals, polyanhydrides, vinyl polymers (e.g., poly (vinyl ethers), poly (vinyl alcohols), poly (vinyl ketones), poly (vinyl halides) (e.g., poly (vinyl chloride)), poly (vinyl nitriles), poly (vinyl esters)), polysulfonates, fluoropolymers (e.g., polyvinylidene fluoride (PVDF), fluorinated ethylene-propylene (FEP), polyethylene tetrafluoroethylene (PETFE)), or a combination comprising at least one of the foregoing. Thermoplastic polymerizationThe article can include a poly (aryl) ether ketone (e.g., poly (ether ketone), poly (ether ketone), and poly (ether ketoneketone)), a polysulfone (e.g., poly (ether sulfone)), a poly (phenylene sulfide), a poly (ether imide), a poly (amide imide), a fluoropolymer, or a combination comprising at least one of the foregoing. The thermoplastic polymer may include a polyolefin. The thermoplastic polymer can include a combination of at least one of the foregoing polymers.

The thermoplastic polymer may comprise poly (aryl) ether ketones, such as poly (ether ketone), poly (ether ketone), and poly (ether ketone). For example, the thermoplastic polymer may comprise poly (ether ketone). The melt flow rate (MRF) of the poly (ether ketone), as determined at 400 ℃ under a load of 2.16 kilograms (kg) according to ASTM D1238-13, procedure a, can be from 40 grams/10 minutes (g/10 minutes) to 50 grams/10 minutes.

The thermoplastic polymer may include a polyolefin. The polyolefin may comprise low density polyethylene. The polyolefin may include a cyclic olefin copolymer (e.g., a copolymerization product of norbornene and ethylene using a metallocene catalyst) optionally in combination with a linear polyolefin. The cyclic olefin copolymer may have one or more of the following: a tensile strength at yield of 40 to 50 megapascals (MPa) at 5 millimeters per minute (mm/min) as measured according to ISO 527-2/1a: 2012; a dielectric constant of 2 to 2.5 at a frequency of 1 kilohertz (kHz) to 10 kHz as determined according to IEC 60250; and a heat distortion temperature at 0.46MPa of greater than or equal to 125 ℃, e.g. 135 ℃ to 160 ℃, as determined according to ISO 75-1, -2: 2004.

The thermoplastic composite may include a liquid crystal polymer. Liquid crystal polymers (sometimes abbreviated as "LCPs") are a well-known class of polymers used for a variety of purposes. Liquid crystal polymers typically include thermoplastic resins, although they may also be used as thermosets by functionalization or by compounding with thermosets (e.g., epoxy resins). Liquid crystal polymers are considered to have a fixed molecular shape (e.g., linear) due to the nature of the repeating units in the polymer chain. The repeating units typically comprise rigid molecular elements. Rigid molecular elements (mesogens) are often rod-like or disk-like in shape, and are usually aromatic and often heterocyclic. Rigid molecular elements may be present in one or both of the main chains (backbones) of the polymer as well as in the side chains. Rigid molecular elements may be separated by more flexible molecular elements (sometimes referred to as spacer groups).

Examples of commercial liquid crystal polymers include, but are not limited to, VECTRA commercially available from Celanese^TMAnd ZENITE^TMAnd XYDAR commercially available from Solvay Specialty Polymers^TMAnd those available from RTP co, such as RTP-3400 series liquid crystal polymers.

The thermoplastic composite may comprise from 10 to 90, or from 20 to 80, or from 20 to 70, or from 20 to 60, or from 10 to 20 percent by volume of the liquid crystalline polymer, based on the total volume of the thermoplastic composite. The thermoplastic composite may comprise 20 to 80 volume percent, or 40 to 80 volume percent of a thermoplastic polymer other than a liquid crystal polymer and 10 to 20 volume percent of a liquid crystal polymer, based on the total volume of the thermoplastic composite.

The thermoplastic composite includes a dielectric filler that may be selected to adjust the dielectric constant, dissipation factor, coefficient of thermal expansion, and other properties of the composition. The dielectric filler has a multi-modal particle size distribution, wherein a peak of a first mode of the multi-modal particle size distribution is at least seven times a peak of a second mode of the multi-modal particle size distribution. The multimodal particle size distribution may be, for example, bimodal, trimodal, or tetramodal. In other words, the dielectric filler comprises a first plurality of particles having a first average particle size and a second plurality of particles having a second average particle size; wherein the first average particle size is greater than or equal to 7 times, or greater than or equal to 10 times, or from 7 times to 60 times, or from 7 times to 20 times the second average particle size. As used herein, the term particle size refers to the diameter of a sphere having the same volume as the particle, and the average particle size refers to the numerical average of the particle sizes of a plurality of particles. The peak of the first mode (first average particle size) may be greater than or equal to 2 microns, or from 2 microns to 20 microns. The peak of the second mode (second average particle size) may be greater than or equal to 0.2 microns, or less than or equal to 2 microns, or 0.2 microns to 1.5 microns.

The first plurality of particles and the second plurality of particles may comprise the same dielectric filler. For example, the first plurality of particles and the second plurality of particles may comprise titanium dioxide. Rather, the first plurality of particles and the second plurality of particles may comprise different dielectric fillers. For example, the first plurality of particles may comprise silica and the second plurality of particles may comprise titania.

The first plurality of particles may have an average particle size of 1 micron to 10 microns, or 2 microns to 5 microns. The second plurality of particles may have an average particle size of 0.01 microns to 1 micron, or 0.1 microns to 0.5 microns. The dielectric filler may include a first plurality of particles including titanium dioxide having an average particle size of 1 micron to 10 microns and a second plurality of particles having an average particle size of 0.1 micron to 1 micron.

The thermoplastic composite may comprise 10 to 90 volume percent, or 20 to 80 volume percent, or 30 to 80 volume percent, or 40 to 80 volume percent of the dielectric filler, based on the total volume of the thermoplastic composite. The thermoplastic composite may comprise 25 to 45 volume percent, or 30 to 40 volume percent of the first plurality of particles and 10 to 25 volume percent, or 10 to 20 volume percent of the second plurality of particles; both based on the total volume of the thermoplastic composite. The dielectric filler may include 10 to 90 volume percent, or 50 to 90 volume percent, or 60 to 80 volume percent of the first plurality of particles based on the total volume of the dielectric filler. The dielectric filler may include 10 to 90 volume percent, or 10 to 50 volume percent, or 20 to 40 volume percent of the second plurality of particles based on the total volume of the dielectric filler.

The dielectric filler may include titanium dioxide (e.g., rutile and anatase), barium titanate, strontium titanate, silicon dioxide (e.g., fumed amorphous silicon dioxide), corundum, wollastonite, Ba₂Ti₉O₂₀Solid glass spheres, hollow microspheres (e.g., hollow glass spheres and hollow ceramic spheres), quartz, boron nitride, aluminum nitride, silicon carbide, beryllium oxide, aluminum trihydrate, magnesium oxide, mica, talc, and the likeStone, nanoclay, magnesium hydroxide, or a combination comprising at least one of the foregoing. The dielectric filler may include titanium dioxide, silicon dioxide, barium titanate, or a combination comprising at least one of the foregoing. The dielectric filler may comprise hollow microspheres. The shape of the dielectric filler can be one or more of spherical, platelet, or irregular, for example as an agglomerate. The dielectric filler may be free of fibrous components.

The dielectric filler may include treated titanium dioxide. For example, the titanium dioxide may be sintered to increase the amount of the desired phase. Without wishing to be bound by theory, it is believed that sintering may help the composition achieve lower dielectric losses. A first plurality of titanium dioxide particles having an average particle size of 1 micron to 10 microns, or 2 microns to 5 microns may be sintered. A first plurality of titanium dioxide particles having an average particle size of 0.1 to 1 micron, or 0.1 to 0.5 microns, may be sintered.

If the dielectric filler comprises a plurality of hollow microspheres, the average outer diameter of the first plurality of hollow microspheres may be from 70 microns to 300 microns, or from 10 microns to 200 microns, and the average outer diameter of the second plurality of hollow microspheres may be from 10 microns to 50 microns, or from 20 microns to 45 microns. The hollow microspheres can have a density of greater than or equal to 0.1 grams per cubic centimeter (g/cc), or from 0.2g/cc to 0.6g/cc, or from 0.3g/cc to 0.5 g/cc. Hollow microspheres are available from many commercial sources, for example, from Trelleborg offset (Boston) (formerly Emerson and Cuming, Inc.), w.r.grace and Company (Canton, MA), and 3M Company (st.paul, MN.). Such hollow microspheres are also known as microballoons (microballons), glass bubbles and microbubbles, and are sold in different grades, which may vary, for example, according to density, size, coating and/or surface treatment. The hollow microspheres may include ceramic hollow microspheres, polymeric hollow microspheres, glass hollow microspheres (e.g., those made of alkali borosilicate glass), or a combination comprising one or more of the foregoing.

The dielectric filler may be surface treated with a silicon-containing coating such as an organofunctional alkoxysilane coupling agent. Zirconate coupling agents or titanate coupling agents may be used. Such coupling agents may improve the dispersibility of the filler in the thermoplastic composite and reduce the water absorption of articles made therefrom.

The silane coating can be formed from silanes, which can include linear silanes, branched silanes, cyclic silanes, or a combination comprising at least one of the foregoing. The silane may include precipitated silane. The silane may be free of solvent (e.g., toluene) or dispersed silane, e.g., the silane may comprise 0 to 2 weight percent (e.g., 0 weight percent) solvent dispersed silane based on the total weight of the silane.

A variety of different silanes may be used to form the coating, including one or both of phenylsilane and fluorosilane. The phenylsilane can be p-chloromethylphenyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltrichlorosilane, phenyl-tris- (4-biphenyl) silane, hexaphenyldisilane, tetrakis- (4-biphenyl) silane, tetra-Z-thiophenilane, phenyltri-Z-thiophenilane, 3-pyridyltriphenylsilane, or a combination comprising at least one of the foregoing. Functionalized phenylsilanes, such as of the formula R, as described in US 4,756,971, may also be used¹SiZ¹Z²Z³Of a functional phenylsilane, wherein Z¹And Z²Each independently of the others being chlorine, fluorine, bromine, alkoxy having not more than 6 carbon atoms, NH, -NH₂、-NR₂'(wherein R' is an alkyl group having 1 to 3 carbon atoms), -SH, -CN, -N₃Or hydrogen, and R¹Is composed of

Wherein S-substituent S₁、S₂、S₃、S₄And S₅Each independently selected from hydrogen, alkyl having 1 to 4 carbon atoms, methoxy, ethoxy and cyano, provided that at least one of the S-substituents is other than hydrogen, and when a methyl or methoxy S-substituent is present then (i) at least two of the S-substituents are other than hydrogen, (ii) two adjacent S-substituents form a naphthyl or anthracenyl group with the phenyl core, or (iii) three adjacent S-substituents form a naphthyl or anthracenyl groupThe substituent and the phenyl nucleus together form a pyrenyl group, and X is a group- (CH)₂)_n-, where n is 0 to 20, or 10 to 16 when n is not 0, i.e. X is a spacer, S-substituent. The term "lower" in relation to a group or compound means 1 to 7 or 1 to 4 carbon atoms.

The fluorosilane coating may be formed from a coating having the formula: CF (compact flash)₃(CF₂)_n-CH₂CH₂A perfluorinated alkylsilane of SiX, wherein X is a hydrolyzable functional group and n is 0 or all integers. The fluorosilane may be (3,3, 3-trifluoropropyl) trichlorosilane, (3,3, 3-trifluoropropyl) dimethylchlorosilane, (3,3, 3-trifluoropropyl) methyldichlorosilane, (3,3, 3-trifluoropropyl) methyldimethoxysilane, (tridecafluoro-1, 1,2, 2-tetrahydrooctyl) -1-trichlorosilane, (tridecafluoro-1, 1,2, 2-tetrahydrooctyl) -1-methyldichlorosilane, (tridecafluoro-1, 1,2, 2-tetrahydrooctyl) -1-dimethylchlorosilane, (heptadecafluoro-1, 1,2, 2-tetrahydrodecyl) -1-methyldichlorosilane, (heptadecafluoro-1, 1,2, 2-tetrahydrodecyl) -1-trichlorosilane, or, (heptadecafluoro-1, 1,2, 2-tetrahydrodecyl) -1-dimethylchlorosilane, (heptafluoroisopropoxy) propylmethyldichlorosilane, 3- (heptafluoroisopropoxy) propyltrichlorosilane, 3- (heptafluoroisopropoxy) propyltriethoxysilane, or a combination comprising at least one of the foregoing.

Other silanes may be used in place of or in addition to phenylsilane and fluorosilane, for example, aminosilanes and silanes containing polymerizable functional groups such as acryloyl and methacryloyl groups. Examples of aminosilanes include N-methyl-gamma-aminopropyltriethoxysilane, N-ethyl-gamma-aminopropyltrimethoxysilane, N-methyl-beta-aminoethyltrimethoxysilane, gamma-aminopropylmethyldimethoxysilane, N-methyl-gamma-aminopropylmethyldimethoxysilane, N- (beta-N-methylaminoethyl) -gamma-aminopropyltriethoxysilane, N- (gamma-aminopropyl) -gamma-aminopropylmethyldimethoxysilane, N- (gamma-aminopropyl) -N-methyl-gamma-aminopropylmethyldimethoxysilane and gamma-aminopropylethyldiethoxysilylaminoethylaminotrimethoxysilane, Aminoethylaminopropyltrimethoxysilane, 2-ethylpiperidinyltrimethylsilane, 2-ethylpiperidinylmethylchlorosilane, 2-ethylpiperidinyldimethylhydrosilane, 2-ethylpiperidinyldicyclopentylchlorosilane, (2-ethylpiperidinyl) (5-hexenyl) methylchlorosilane, morpholinovinylmethylchlorosilane, N-methylpiperazinylphenyldichlorosilane, or a combination comprising at least one of the foregoing.

Silanes containing polymerizable functional groups include the formula R^a _xSiR^b _(3-x)Silane of R, wherein each R^aIdentical or different, e.g. identical and being halogen (e.g. Cl and Br), C_1-4Alkoxy radical, C_2-6Acyl such as methoxy or ethoxy; each R^bIs C_1-8Alkyl or C_6-12Aryl, for example, methyl, ethyl, propyl, butyl, or phenyl; x is 1,2 or 3, e.g., 2 or 3; and R is- (CH)₂)_nOC(＝O)C(R^c)＝CH₂Wherein R is^cIs hydrogen or methyl and n is an integer from 1 to 6, for example from 2 to 4. The silane can be a methacryloyl silane (e.g., 3-methacryloxypropyltrimethoxysilane).

The titanate coating may be formed from: neopentyl (diallyl) oxy, trineodecanoyl titanate; neopentyl (diallyl) oxy, tridodecyl benzenesulfonyl titanate; neopentyl (diallyl) oxy, tris (dioctyl) phosphate titanate; neopentyl (diallyl) oxy, tris (dioctyl) pyrophosphate titanate; neopentyl (diallyl) oxy, tris (N-ethylenediamino) ethyl titanate; neopentyl (diallyl) oxy, tris (meta-amino) phenyl titanate; and neopentyl (diallyl) oxy, trihydroxyhexanoyl titanate; or a combination comprising at least one of the foregoing. The zirconate coating may be formed of neopentyl (diallyloxy) tris (dioctyl) pyrophosphate zirconate, neopentyl (diallyloxy) tris (N-ethyldiamino) ethyl zirconate, or a combination comprising at least one of the foregoing.

The thermoplastic composite may comprise a flow modifier. The flow modifier may include a ceramic filler. The ceramic filler may include one or more of the dielectric fillers listed herein, provided thatThe ceramic filler is different from the dielectric filler. For example, the dielectric filler may include titanium dioxide and the ceramic filler may include boron nitride. The flow modifier may comprise a fluoropolymer (e.g., a perfluoropolyether liquid), such as FLUOROGARD commercially available from Chemours USA fluoropolymers, Wilmington, DE^TM. The flow modifier may include polyhedral oligomeric silsesquioxanes (commonly referred to as "POSS," also referred to herein as "silsesquioxanes"). The flow modifier can include a combination comprising one or more of the foregoing flow modifiers. The flow modifier may be present in an amount of less than or equal to 5 volume percent, or 0.5 to 2 volume percent, based on the total volume of the thermoplastic composite. At these low concentrations, the dielectric constant of the thermoplastic composite will not be significantly affected.

The flow modifier may comprise a silsesquioxane. Silsesquioxanes are nano-sized inorganic materials having a silica core that can have reactive functional groups on the surface. The silsesquioxane can have a cubic or cuboidal structure comprising silicon atoms at vertices and interconnecting oxygen atoms. Each silicon atom may be covalently bonded to a pendant R group. Silsesquioxanes, e.g. octa (dimethylsiloxy) silsesquioxane (R)₈Si₈O₁₂) A cage comprising silicon and oxygen atoms surrounding a core with eight pendant R groups. Each R group can independently be hydrogen, hydroxyl, alkyl, aryl, or alkenyl, where the R groups can comprise 1 to 12 carbon atoms and one or more heteroatoms (e.g., oxygen, nitrogen, phosphorus, silicon, halogen, or a combination comprising at least one of the foregoing). Each R group can independently comprise a reactive group, such as an alcohol, epoxy, ester, amine, ketone, ether, halide, or a combination comprising at least one of the foregoing. Each R group can independently comprise a silanol, an alkoxide, a chloride, or a combination comprising at least one of the foregoing. The silsesquioxane can include trisilanolphenyl POSS, dodecaphenyl POSS, octaisobutyl POSS, octamethyl POSS, or a combination comprising at least one of the foregoing. The silsesquioxane may include trisilanol phenyl POSS.

The thermoplastic composite may include additives, such as fibrous fillers, flame retardants, mold release agents, or a combination comprising at least one of the foregoing. The fibrous filler can include glass fibers, carbon fibers, wollastonite fibers, aluminum borate fibers, potassium titanate whiskers, or a combination comprising at least one of the foregoing. The fibrous filler may comprise glass fibers, for example, CS03JAPx-1 manufactured by Asahi fiber glass Corp. The glass fibers may comprise chopped glass strands. The glass fibers may comprise milled fibers.

The thermoplastic composite may include a flame retardant for rendering the thermoplastic composite flame resistant. The flame retardant may be halogenated or non-halogenated. The flame retardant may be present in the thermoplastic composite in an amount of 0 to 30 volume percent based on the volume of the thermoplastic composite.

The flame retardant may be inorganic and may be present in particulate form. The inorganic flame retardant may include a metal hydrate having a volume average particle diameter of, for example, 1 to 500 nanometers (nm), or 1 to 200nm, or 5 to 200nm, or 10 to 200 nm; alternatively, the volume average particle size may be 500nm to 15 microns, for example 1 micron to 5 microns. The metal hydrate may include hydrates of the following metals: such as Mg, Ca, Al, Fe, Zn, Ba, Cu, Ni, or a combination comprising at least one of the foregoing. Hydrates of Mg, Al, or Ca, such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, iron hydroxide, zinc hydroxide, copper hydroxide, and nickel hydroxide; and hydrates of gypsum dihydrate, zinc borate, barium metaborate and calcium aluminate. A composite of these hydrates may be used, for example, a hydrate containing Mg and at least one selected from Ca, Al, Fe, Zn, Ba, Cu, and Ni. The composite metal hydrate may have the formula MgM_x(OH)_yWherein M is Ca, Al, Fe, Zn, Ba, Cu, or Ni, x is 0.1 to 10, and y is 2 to 32. The flame retardant particles may be coated or otherwise treated to improve dispersion characteristics and other characteristics.

Organic flame retardants may be used instead of, or in addition to, inorganic flame retardants. Examples of organic flame retardants include melamine cyanurate, fine particle size melamine polyphosphate, various other phosphorus-containing compounds such as aromatic phosphinates, diphosphonites, phosphonates, phosphates, siloxanes, and halogenated compounds (e.g., hexachloroendomethylenetetrahydrophthalic acid (HET acid), tetrabromophthalic acid, and dibromoneopentyl glycol). The flame retardant (e.g., a bromine-containing flame retardant) can be present in an amount of 20phr (parts by weight per 100 parts of the thermoplastic composite) to 60phr, or 30phr to 45 phr. Examples of brominated flame retardants include Saytex BT93W (ethylenebistetrabromophthalimide), Saytex 120 (tetradecylbenzoyloxybenzene), and Saytex 102 (decabromodiphenyl oxide). The flame retardant may be used in combination with a synergist, for example, a halogenated flame retardant may be used in combination with a synergist (e.g., antimony trioxide), and a phosphorus-containing flame retardant may be used in combination with a nitrogen-containing compound (e.g., melamine).

The thermoplastic composite material can have a dielectric constant (also referred to as dielectric permeability) of greater than or equal to 1.5, or greater than or equal to 2.5, or 1.5 to 8, or 3 to 13, or 3.5 to 8, or 5 to 8 at 500MHz to 10 GHz. The thermoplastic composite may have a dielectric constant at 500MHz to 10GHz of greater than or equal to 10, or 10 to 20. The thermoplastic composite can have a dielectric loss at 500MHz to 10GHz of less than or equal to 0.007, or less than or equal to 0.005, or 0.001 to 0.005. Dielectric properties can be measured using a coaxial air line with a Nicholsson-Ross extraction from scattering parameters measured using a vector network analyzer at room temperature of 23 ℃.

The thermoplastic composite may be melt processed, for example, by injection molding, 3D printing, or extrusion. As used herein, the term "melt processable" may refer to any process in which a thermoplastic polymer is melted, for example, to a temperature above its glass transition temperature, and then solidified, for example, to a temperature below its glass transition temperature to form a shape. The thermoplastic composite may be formed into an article. The article may be formed using an injection molding process that includes: injecting the thermoplastic composite in molten form into a mold; and cooling the mold to form the article. The method can comprise the following steps: first forming a mixture comprising a thermoplastic polymer and a dielectric filler; and mixing the mixture thoroughly, wherein the mixture can be melted prior to and/or during mixing.

Circuit materials comprising thermoplastic composites can be prepared by forming a multilayer material having a substrate layer comprising a thermoplastic composite and an electrically conductive layer disposed thereon. Useful conductive layers include, for example, stainless steel, copper, gold, silver, aluminum, zinc, tin, lead, transition metals, and alloys comprising at least one of the foregoing. There is no particular limitation on the thickness of the conductive layer, nor is there any limitation on the shape, size, or surface texture of the conductive layer. The thickness of the conductive layer may be 3 to 200 micrometers, or 9 to 180 micrometers. When two or more conductive layers are present, the thicknesses of the two layers may be the same or different. The conductive layer may include a copper layer. Suitable conductive layers include thin layers of conductive metals such as copper foil currently used to form circuits, e.g., electrodeposited copper foil. The Root Mean Square (RMS) roughness of the copper foil may be less than or equal to 2 microns, or less than or equal to 0.7 microns, where the roughness is measured using a Veeco instrument WYCO optical profiler using a white light interference method.

The conductive layer may be applied by: by placing the conductive layer in a mold prior to molding the thermoplastic composite, by laminating the conductive layer to the substrate, by direct laser structuring, or by adhering the conductive layer to the substrate via an adhesive layer. Other methods known in the art may be used to apply the conductive layer to the allowed places and form the circuit material by specific materials, such as electrodeposition and chemical vapor deposition.

Lamination may entail laminating a multilayer stack comprising a substrate, an electrically conductive layer and optionally intermediate layers between the substrate and the electrically conductive layer to form a layered structure. The conductive layer may be in direct contact with the base layer without an intermediate layer. The layered structure may then be placed in a press (e.g., a vacuum press) under pressure and temperature for a duration suitable to bond the layers and form a laminate. Lamination and optional curing may be by a one-step process, for example using a vacuum press, or may be by a multi-step process. In the one-step process, the layered structure can be placed in a press, increased to a lamination pressure (e.g., 150 pounds per square inch (psi) to 400 psi), and heated to a lamination temperature (e.g., 260 ℃ to 390 ℃). The lamination temperature and pressure may be maintained for a desired dwell time (soak time), for example, 20 minutes, after which it is cooled (while still under pressure) to less than or equal to 150 ℃.

If present, the interlayer can include a polyfluorocarbon film that can be positioned between the conductive layer and the substrate layer, and the optional microglass reinforced fluorocarbon polymer layer can be positioned between the polyfluorocarbon film and the conductive layer. The microglass-reinforced fluorocarbon polymer layer can improve the adhesion of the conductive layer to the substrate. The microglass may be present in an amount of 4 weight percent (wt%) to 30 wt%, based on the total weight of the layer. The longest length scale of the microglass can be less than or equal to 900 micrometers, or less than or equal to 500 micrometers. The microglass may be a type of microglass as is commercially available through Johns-Manville corporation of Denver, Colorado. Polyfluorocarbon membranes include fluoropolymers such as Polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene copolymers such as teflon FEP, and copolymers having a tetrafluoroethylene backbone and fully fluorinated alkoxy side chains such as teflon PFA.

The conductive layer may be applied by laser direct structuring. Here, the substrate may include a laser direct structuring additive; and laser direct structuring may include irradiating the surface of the substrate with a laser, forming tracks of a laser direct structuring additive, and applying a conductive metal to the tracks. The laser direct structuring additive may include metal oxide particles (e.g., titanium oxide and copper chromium oxide). The laser direct structuring additive may comprise spinel based inorganic metal oxide particles, such as spinel copper. The metal oxide particles can be coated, for example, with a composition comprising tin and antimony (e.g., 50 to 99 weight percent tin and 1 to 50 weight percent antimony, based on the total weight of the coating). The laser direct structuring additive may comprise 2 to 20 parts of the additive based on 100 parts of the corresponding composition. Irradiation may be performed with a YAG laser having a wavelength of 1,064 nm at an output power of 10 watts, a frequency of 80kHz, and a rate of 3 m/sec. The conductive metal may be applied using a plating process in an electroless plating bath containing, for example, copper.

The conductive layer may be applied by adhesively applying the conductive layer. The conductive layer may be a circuit (metallization layer of another circuit), such as a flexible circuit. An adhesive layer may be disposed between the one or more conductive layers and the substrate. When appropriate, the adhesive layer may comprise poly (arylene ether); and a carboxyl-functionalized polybutadiene or polyisoprene polymer comprising butadiene, isoprene or butadiene and isoprene units, and from 0 to 50 weight percent of co-curable monomer units. The adhesive layer may be present in an amount of 2 grams per square meter to 15 grams per square meter. The poly (arylene ether) may comprise a carboxyl-functionalized poly (arylene ether). The poly (arylene ether) may be the reaction product of a poly (arylene ether) and a cyclic anhydride, or the reaction product of a poly (arylene ether) and maleic anhydride. The carboxyl-functionalized polybutadiene or polyisoprene polymer may be a carboxyl-functionalized butadiene-styrene copolymer. The carboxyl-functionalized polybutadiene or polyisoprene polymer may be the reaction product of a polybutadiene or polyisoprene polymer and a cyclic anhydride. The carboxyl-functionalized polybutadiene or polyisoprene polymer may be a maleated polybutadiene-styrene or maleated polyisoprene-styrene copolymer.

The thermoplastic composite materials may be used in electronic devices such as inductors on electronic integrated circuit chips, electronic circuits, electronic packages, modules, housings, transducers, ultra-high frequency (UHF) antennas, Very High Frequency (VHF) antennas, and microwave antennas for a variety of applications such as power applications, data storage, and microwave communications. The thermoplastic composite may be used in electronic devices, such as mobile internet devices. The thermoplastic composite may be used in electronic devices such as cell phones, tablets, laptops, and internet watches. The thermoplastic composite material may be used in applications where an external dc magnetic field is applied. Additionally, in all antenna designs in the frequency range of 1GHz to 10GHz, thermoplastic composites can be used with very good results (size and bandwidth). The antenna may be a planar inverted-F antenna, a patch antenna, a dipole antenna, or a meander-line antenna. The thermoplastic composite may be used in radio-frequency (RF) assemblies.

The thermoplastic composite may be used in a three-dimensional (3D) printing process. For example, the thermoplastic composite may be in the form of a filament or powder, and the filament or powder may be used in 3D printing using Fused Deposition Modeling (FDM) methods.

The following examples are provided to illustrate thermoplastic composites. These examples are illustrative only and are not intended to limit devices made in accordance with the present disclosure to the materials, conditions, or process parameters set forth therein.