Polypropylene composition for use in high-frequency radio wave applications

Abstract

The polypropylene composition for use in high-frequency radio wave applications above 6 GHz includes a mixture of polypropylene and hollow glass bubbles with an average diameter or particle size of 5 μm to 80 μm. The polypropylene composition further includes at least one of glass fibers with a length of 0.5 mm to 10 mm and a width or diameter of 5 μm to 15 μm, aluminum oxide fibers with a length of 1 mm to 5 mm and a width or diameter of 1 μm to 30 μm, a cyclic olefin copolymer, and a polycarbonate. The polypropylene composition is prepared by modifying polypropylene by melt-kneading polypropylene with various materials.

Description

Technical Field

[0001] The present invention relates to a polypropylene composition for use in high-frequency radio wave applications.

Background Art

[0002] With the emergence of 5G communication technology and related equipment, there is a demand for low-cost and lightweight polymer materials with low dielectric constant (Dk) and dielectric tangent (Df) values, high metal adhesion strength, low coefficient of thermal expansion (CTE), and good mechanical and thermal properties. Currently, FR-4 glass-reinforced epoxy laminate materials are widely used as antenna substrates for sub-6 GHz frequency applications. FR-4 laminate is considered unsuitable for high-frequency (i.e., >6 GHz) applications because of its high Dk (>4) and Df (>0.01) values.

[0003] On the other hand, materials such as polytetrafluoroethylene (PTFE), liquid crystal polymer (LCP), and modified polyimide (M-PI) are considered suitable materials for high-frequency (>6 GHz) antennas and other sub-segment applications because of their low Dk and Df values. However, these materials are very expensive and do not meet the lightweight criteria required for the target applications, apart from other specific issues associated with each material. In particular, the use of PTFE brings several issues such as higher system costs including both material and processing costs, inferior metal adhesiveness, high CTE in the z-axis direction, and higher density.

[0004] In this regard, even at higher frequencies (e.g., 47 - 75 GHz), since the Dk (about 2.225) and Df (about 0.0019) are low, other commercially available polymer materials such as polypropylene (PP) can be selected. However, the mechanical and thermal properties of neat polypropylene are not sufficient to meet specific manufacturing and processing steps and usage conditions. Although blending specific additives into polypropylene may improve the mechanical and thermal properties, the dielectric and metal adhesion properties of polypropylene may be affected by these additives.

[0005] Therefore, since the modified polypropylene has low Dk and Df values, high metal adhesion strength, low CTE, as well as good mechanical and thermal properties, it is necessary to modify polypropylene with additives that bring about a synergistic effect to be suitable for high-frequency (>6 GHz) applications.

Summary of the Invention

[0006] A polypropylene composition for use in high-frequency radio wave applications of 6 GHz or higher includes a mixture of polypropylene, hollow glass bubbles having an average diameter or particle diameter of 5 μm to 80 μm, and at least one or several additives. Examples of the additives include at least one glass fiber having a length of 0.5 mm to 10 mm and a width or diameter of 5 μm to 15 μm, aluminum oxide fibers having a length of 1 mm to 5 mm and a width or diameter of 1 μm to 30 μm, cyclic olefin copolymer, and polycarbonate.

[0007] In a specific embodiment, the above composition includes hollow glass bubbles in an amount of 1 wt% to 35 wt%. The hollow glass bubbles may have at least one of a crushing strength of 30 MPa or more, a true density of 0.3 g / cc to 0.8 g / cc, and a gas content of 50% to 90%.

[0008] The above glass fiber may be present in an amount of 40% by weight or less based on the total weight of the composition. The above glass fiber may have at least one of a dielectric constant (Dk) of 4 or more measured at 6 MHz or more in accordance with ASTM D150, a dielectric tangent (Df) of 0.005 or less measured at 6 MHz or more in accordance with ASTM D150, and a coefficient of thermal expansion (CTE) of 35×10-6 / °C or less measured in accordance with ASTM D696.

[0009] The composition may further contain the above aluminum oxide fiber in an amount of 40% by weight or less based on the total weight of the composition.

[0010] The above polypropylene is a 2 and 4 ~ 10 copolymer having a comonomer selected from olefin monomers, and the above comonomer may be present in the copolymer in an amount of 15% by weight or less.

[0011] The cyclic olefin copolymer may also be present in an amount of 20% by weight or less based on the total weight of the composition. When included, the polycarbonate may be present in an amount of 20% by weight or less based on the total weight of the composition. The composition may also contain at least one of polyvinylcyclohexane and poly(1,4-cyclohexylidene cyclohexane-1,4-dicarboxylate).

[0012] Various other additives may also be included in the composition. The additives may include stabilizers, coupling agents, compatibilizers, thermal conductivity agents, flame retardant additives, thermal conductivity additives, binders, antiblocking agents, antistatic agents, antioxidants, neutralizing agents, acid scavengers, foaming agents, nucleating agents, crystallization aids, dyes, flame retardants, fillers, hard fillers, soft fillers, impact modifiers, mold release agents, oils, other polymers, pigments, processing agents, reinforcing agents, light stabilizers, ultraviolet resistant agents, lubricants, flow improvers, and combinations thereof.

[0013] The above polypropylene composition may have a Dk value of 2.5 or less when measured at 6 GHz or higher, and a Df value of 0.005 or less when measured at 6 GHz or higher. The above polypropylene composition may have at least one of the following: a metal adhesion peel strength of 0.1 N / mm or more measured according to ASTM B533 or IPC-TM-650; a coefficient of thermal expansion (CTE) of 60 ppm / °C or less measured according to ASTM D696; a heat distortion temperature (HDT) of 100 °C or more measured according to ASTM D648; a water absorption rate of 0.05 wt% or less measured according to ASTM D570; a tensile modulus of 2000 MPa or more measured according to ASTM D638; a tensile strength of 35 MPa or more measured according to ASTM D638; a density of 1.4 g / cc or less; a UL94 flame retardancy grade of V0@1.5 mm; and a thermal conductivity of 0.2 W / mK or more measured according to ASTM C518.

[0014] The above polypropylene composition can be formed into a manufactured article. The above manufactured article may be an electrical communication device or component, a high-frequency (>6 GHz) electrical device, a high-frequency (>6 GHz) multi-generation electrical communication device or component, a 5G or higher-generation electrical communication antenna and end-use device or component, an electrical communication device housing, a radome cover, a high-frequency (RF) filter, an RF connector, an EMI shield, an antenna substrate, a waveguide substrate or carrier, an antenna substrate for a base station antenna, or an automotive radar component.

[0015] In a method for forming a polypropylene composition for use in high-frequency radio wave applications of 6 GHz or higher, the polypropylene is modified by melt-kneading the polypropylene with various materials. The various materials include hollow glass bubbles having an average diameter or particle diameter of 5 μm to 80 μm, glass fibers having a length of 0.5 mm to 10 mm and a width or diameter of 5 μm to 15 μm, aluminum oxide fibers having a length of 1 mm to 5 mm and a width or diameter of 1 μm to 15 μm, a cyclic olefin copolymer, and a polycarbonate, whereby the materials are dispersed throughout the polypropylene.

[0016] In some embodiments of the present disclosure, a polypropylene composition for use in high-frequency radio wave applications above 6 GHz comprises a mixture of (i) polypropylene, (ii) hollow glass bubbles having an average diameter or particle diameter of 5 μm to 80 μm, (iii) at least one of glass fibers having a length of 0.5 mm to 10 mm and a width or diameter of 5 μm to 15 μm, and aluminum oxide fibers having a length of 1 mm to 5 mm and a width or diameter of 1 μm to 30 μm, and (iv) at least one of a cyclic olefin copolymer and a polycarbonate. Detailed Description of the Invention

[0017] Compared with the high-cost materials currently used in high-frequency radio wave applications, polypropylene (PP) is an easily available and relatively low-cost material. However, due to the inherent drawbacks of neat polypropylene at high frequencies, polypropylene has not been widely used in high-frequency radio wave applications. In the present invention, these drawbacks are overcome by melt-kneading polypropylene with a synergistic mixture of additives that make the polypropylene composition suitable for use in high-frequency radio wave applications above 6 GHz.

[0018] By applying the modified polypropylene, the modified polypropylene is lightweight, has a low dielectric constant (Dk), a low dielectric tangent (Df), a high metal adhesion strength, a low coefficient of thermal expansion (CTE), a high mechanical strength, and good thermal performance. These properties can be achieved by using a blend of polypropylene and the specific additives described herein.

[0019] The polypropylene component of the polymer blend may comprise a homopolymer of propylene. The polypropylene is typically an isotactic polypropylene such as polypropylene formed from a Ziegler-Natta catalyst. The polypropylene is typically unimodal, but may have a wide range of molecular weight distribution or polydispersity index (PDI) and melt flow index (MFI). An example of a suitable commercially available polypropylene homopolymer is SABIC® PP571 polypropylene available from Saudi Basic Industries Corporation, Riyadh, Saudi Arabia.

[0020] In other embodiments, the polypropylene component is ethylene and / or at least one C 4 ~C 10It can include copolymers of non-propylene monomers such as α-olefins. Typically, in the case of non-ethylene comonomers, the monomer is at least one of α-olefins of butene, hexene and / or octene. When the above copolymer is used, the non-propylene comonomer component may be present in an amount of 15% by weight or less in the polypropylene copolymer, and in many cases, it is used in an amount of 2% to 15% by weight. In certain embodiments, the non-propylene comonomer component is at least 0.1% by weight, 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.6% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, 1.0% by weight, 1.1% by weight, 1.2% by weight, 1.3% by weight, 1.4% by weight, 1.5% by weight, 1.6% by weight, 1.7% by weight, 1.8% by weight, 1.9% by weight, 2.0% by weight, 2.1% by weight, 2.2% by weight, 2.3% by weight, 2.4% by weight, 2.5% by weight, 2.6% by weight, 2.7% by weight, 2.8% by weight, 2.9% by weight, 3.0% by weight, 3.1% by weight, 3.2% by weight, 3.3% by weight, 3.4% by weight, 3.5% by weight, 3.6% by weight, 3.7% by weight, 3.8% by weight, 3.9% by weight, 4.0% by weight, 4.1% by weight, 4.2% by weight, 4.3% by weight, 4.4% by weight, 4.5% by weight, 4.6% by weight, 4.7% by weight, 4.8% by weight, 4.9% by weight, 5.0% by weight, 5.1% by weight, 5.2% by weight, 5.3% by weight, 5.4% by weight, 5.5% by weight, 5.6% by weight, 5.7% by weight, 5.8% by weight, 5.9% by weight, 6.0% by weight, 6.1% by weight, 6.2% by weight, 6.3% by weight, 6.4% by weight, 6.5% by weight, 6.6% by weight, 6.7% by weight, 6.8% by weight, 6.9% by weight, 7.0% by weight, 7.1% by weight, 7.2% by weight, 7.3% by weight, 7.4% by weight, 7.5% by weight, 7.6% by weight, 7.7% by weight, 7.8% by weight, 7.9% by weight, 8.0% by weight, 8.1% by weight, 8.2% by weight, 8.3% by weight, 8.4% by weight, 8.5% by weight, 8.6% by weight, 8.7% by weight, 8.8% by weight, 8.9% by weight, 9.0% by weight, 9.1% by weight, 9.2% by weight, 9.3% by weight, 9.4% by weight, 9.5% by weight, 9.6% by weight, 9.7% by weight, 9.8% by weight, 9.9% by weight, 10.0% by weight, 10.1% by weight, 10.2% by weight, 10.3% by weight, 10.4% by weight, 10.5% by weight, 10.6% by weight, 10.7% by weight, 10.Amounts from 8 wt%, 10.9 wt%, 11.0 wt%, 11.1 wt%, 11.2 wt%, 11.3 wt%, 11.4 wt%, 11.5 wt%, 11.6 wt%, 11.7 wt%, 11.8 wt%, 11.9 wt%, 12.0 wt%, 12.1 wt%, 12.2 wt%, 12.3 wt%, 12.4 wt%, 12.5 wt%, 12.6 wt%, 12.7 wt%, 12.8 wt%, 12.9 wt%, 13.0 wt%, 13.1 wt%, 13.2 wt%, 13.3 wt%, 13.4 wt%, 13.5 wt%, 13.6 wt%, 13.7 wt%, 13.8 wt%, 13.9 wt%, 14.0 wt%, 14.1 wt%, 14.2 wt%, 14.3 wt%, 14.4 wt%, 14.5 wt%, 14.6 wt%, 14.7 wt%, 14.8 wt%, 14.9 wt%, and 15.0 wt%, amounts equal to the above amounts, and / or amounts between any two of the above amounts may be present.

[0021] In this specification, when a numerical value, concentration or range is indicated, each numerical value should be read once as modified by the term "about" (except when it has already been explicitly so modified), and then again as not so modified, unless the context indicates otherwise. Also, in this specification, it should be understood that ranges of amounts recited or described as useful, suitable, etc. are intended to include every value within the range including the endpoints. For example, the range "1 to 10" should be read as indicating every possible numerical value along the continuum between about 1 and about 10. Thus, even if a particular point within the range, or points within the range, are not explicitly specified or mentioned, the inventor understands that any and all points within the range are considered specified, and the inventor is considered to own the entire range and all points within the range, including smaller ranges within the larger range.

[0022] As discussed throughout the following description, with respect to the polypropylene component of the polypropylene composition, the expression "polypropylene" means both polypropylene homopolymers and polypropylene copolymers, unless explicitly stated otherwise or not apparent from the context.

[0023] The polypropylene component of the composition can be characterized by various properties such as average molecular weight, density, melt flow index (MFI), polydispersity index (PDI), ESCR, tensile strength at yield, tensile modulus, tensile elongation at yield, Izod notched impact strength, hardness, or combinations thereof.

[0024] The average molecular weight (Mw) of the polypropylene component is determined by high temperature gel permeation chromatography. In particular, the average molecular weight (Mw) of the polypropylene can be at least 130,000, 140,000, 150,000, 160,000, 170,000, 180,000, 190,000, 200,000, 210,000, 220,000, 230,000, 240,000, 250,000, 260,000, 270,000, 280,000, 290,000, and 300,000, values equal to the above values, and / or values between any two of the above values, as determined by high temperature gel permeation chromatography. Unless otherwise specified, all average molecular weights (Mw) of the polymers described herein are determined by high temperature gel permeation chromatography.

[0025] The density of the polypropylene is 0.900 g / cm 3 ~0.920 g / cm 3 and can be. In particular, the density of the polypropylene is at least 0.900 g / cm 3 , 0.901 g / cm 3 , 0.902 g / cm 3 , 0.903 g / cm 3 , 0.904 g / cm 3 , 0.905 g / cm 3 , 0.906 g / cm3 , 0.907 g / cm 3 , 0.908 g / cm 3 , 0.909 g / cm 3 , 0.910 g / cm 3 , 0.911 g / cm 3 , 0.912 g / cm 3 , 0.913 g / cm 3 , 0.914 g / cm 3 , 0.915 g / cm 3 , 0.916 g / cm 3 , 0.917 g / cm 3 , 0.918 g / cm 3 , 0.919 g / cm 3 , and 0.920 g / cm 3 Values from, values equal to, and / or values between any two of the above values may also be used.

[0026] The MFI of the polypropylene at 230°C and a load of 2.16 kg may be from 0.1 g / 10 min to 70 g / 10 min according to ISO 1133, or at least 0.1 g / 10 min, 0.2 g / 10 min, 0.3 g / 10 min, 0.4 g / 10 min, 0.5 g / 10 min, 0.6 g / 10 min, 0.7 g / 10 min, 0.8 g / 10 min, 0.9 g / 10 min, 1.0 g / 10 min, 1.1 g / 10 min, 1.2 g / 10 min, 1.3 g / 10 min, 1.4 g / 10 min, 1.5 g / 10 min, 1.6 g / 10 min, 1.7 g / 10 min, 1.8 g / 10 min, 1.9 g / 10 min, 2.0 g / 10 min, 2.1 g / 10 min, 2.2 g / 10 min, 2.3 g / 10 min, 2.4 g / 10 min, 2.5 g / 10 min, 2.6 g / 10 min, 2.7 g / 10 min, 2.8 g / 10 min, 2.9 g / 10 min, 3.0 g / 10 min, 3.1 g / 10 min, 3.2 g / 10 min, 3.3 g / 10 min, 3.4 g / 10 min, 3.5 g / 10 min, 3.6 g / 10 min, 3.7 g / 10 min, 3.8 g / 10 min, 3.9 g / 10 min, 4.0 g / 10 min, 4.1 g / 10 min, 4.2 g / 10 min, 4.3 g / 10 min, 4.4 g / 10 min, 4.5 g / 10 min, 4.6 g / 10 min, 4.7 g / 10 min, 4.8 g / 10 min, 4.9 g / 10 min, 5.0 g / 10 min, 5.1 g / 10 min, 5.2 g / 10 min, 5.3 g / 10 min, 5.4 g / 10 min, 5.5 g / 10 min, 5.6 g / 10 min, 5.7 g / 10 min, 5.8 g / 10 min, 5.9 g / 10 min, 6.0 g / 10 min, 6.1 g / 10 min, 6.2 g / 10 min, 6.3 g / 10 min, 6.4 g / 10 min, 6.5 g / 10 min, 6.6 g / 10 min, 6.7 g / 10 min, 6.8 g / 10 min, 6.9 g / 10 min, 7.0 g / 10 min, 7.1 g / 10 min, 7.2 g / 10 min, 7.3 g / 10 min, 7.4 g / 10 min, 7.5 g / 10 min, 7.6 g / 10 min, 7.7 g / 10 min, 7.8 g / 10 min, 7.9 g / 10 min, 8.0 g / 10 min, 8.1 g / 10 min, 8.2 g / 10 min, 8.3 g / 10 min, 8.4 g / 10 min, 8.5 g / 10 min, 8.6 g / 10 min, 8.7 g / 10 min, 8.8 g / 10 min, 8.9 g / 10 min, 9.0 g / 10 min, 9.1 g / 10 min, 9.2 g / 10 min, 9.3 g / 10 min, 9.4 g / 10 min, 9.5 g / 10 min, 9.6 g / 10 min, 9.7 g / 10 min, 9.8 g / 10 min, 9.9 g / 10 min, 10.Values from 0 g / 10 min, 11 g / 10 min, 12 g / 10 min, 13 g / 10 min, 14 g / 10 min, 15 g / 10 min, 16 g / 10 min, 17 g / 10 min, 18 g / 10 min, 19 g / 10 min, 20 g / 10 min, 21 g / 10 min, 22 g / 10 min, 23 g / 10 min, 24 g / 10 min, 25 g / 10 min, 26 g / 10 min, 27 g / 10 min, 28 g / 10 min, 29 g / 10 min, 30 g / 10 min, 31 g / 10 min, 32 g / 10 min, 33 g / 10 min, 34 g / 10 min, 35 g / 10 min, 36 g / 10 min, 37 g / 10 min, 38 g / 10 min, 39 g / 10 min, 40 g / 10 min, 41 g / 10 min, 42 g / 10 min, 43 g / 10 min, 44 g / 10 min, 45 g / 10 min, 46 g / 10 min, 47 g / 10 min, 48 g / 10 min, 49 g / 10 min, 50 g / 10 min, 51 g / 10 min, 52 g / 10 min, 53 g / 10 min, 54 g / 10 min, 55 g / 10 min, 56 g / 10 min, 57 g / 10 min, 58 g / 10 min, 59 g / 10 min, 60 g / 10 min, 61 g / 10 min, 62 g / 10 min, 63 g / 10 min, 64 g / 10 min, 65 g / 10 min, 66 g / 10 min, 67 g / 10 min, 68 g / 10 min, 69 g / 10 min, and 70 g / 10 min, values equal to the above values, and / or values between any two of the above values may be used.

[0027] In certain cases, the polypropylene may be polypropylene modified to improve processability, such as polypropylene prepared using peroxide shifting. The polypropylene may have a higher MFI than unmodified polypropylene.In particular, modified polypropylenes such as polypropylene prepared using a peroxide shift have an MFI at 230 °C and a load of 2.16 kg that, in accordance with ISO 1133, is 10 g / 10 min or 20 g / 10 min to 100 g / 10 min, or at least 10 g / 10 min, 11 g / 10 min, 12 g / 10 min, 13 g / 10 min, 14 g / 10 min, 15 g / 10 min, 16 g / 10 min, 17 g / 10 min, 18 g / 10 min, 19 g / 10 min, 20 g / 10 min, 21 g / 10 min, 22 g / 10 min, 23 g / 10 min, 24 g / 10 min, 25 g / 10 min, 26 g / 10 min, 27 g / 10 min, 28 g / 10 min, 29 g / 10 min, 30 g / 10 min, 31 g / 10 min, 32 g / 10 min, 33 g / 10 min, 34 g / 10 min, 35 g / 10 min, 36 g / 10 min, 37 g / 10 min, 38 g / 10 min, 39 g / 10 min, 40 g / 10 min, 41 g / 10 min, 42 g / 10 min, 43 g / 10 min, 44 g / 10 min, 45 g / 10 min, 46 g / 10 min, 47 g / 10 min, 48 g / 10 min, 49 g / 10 min, 50 g / 10 min, 51 g / 10 min, 52 g / 10 min, 53 g / 10 min, 54 g / 10 min, 55 g / 10 min, 56 g / 10 min, 57 g / 10 min, 58 g / 10 min, 59 g / 10 min, 60 g / 10 min, 61 g / 10 min, 62 g / 10 min, 63 g / 10 min, 64 g / 10 min, 65 g / 10 min, 66 g / 10 min, 67 g / 10 min, 68 g / 10 min, 69 g / 10 min, 70 g / 10 min, 71 g / 10 min, 72 g / 10 min, 73 g / 10 min, 74 g / 10 min, 75 g / 10 min, 76 g / 10 min, 77 g / 10 min, 78 g / 10 min, 79 g / 10 min, 80 g / 10 min, 81 g / 10 min, 82 g / 10 min, 83 g / 10 min, 84 g / 10 min, 85 g / 10 min, 86 g / 10 min, 87 g / 10 min, 88 g / 10 min, 89 g / 10 min, 90 g / 10 min, 91 g / 10 min, 92 g / 10 min, 93 g / 10 min, 94 g / 10 min, 95 g / 10 min, 96 g / 10 min, 97 g / 10 min, 98 g / 10 min, 99 g / 10 min, and 100 g / 10 min, values equal to the above values, and / or values between any two of the above values.

[0028] The polystyrene component has a polydispersity index (PDI = Mw / Mn) determined by high-temperature gel permeation chromatography of 4 to 10, or at least a value from 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8.0, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, and 10.0, a value equal to the above value, and / or a value between any two of the above values.

[0029] The tensile modulus of the polypropylene is 800 MPa to 2200 MPa, or at least a value from 800 MPa, 850 MPa, 900 MPa, 950 MPa, 1000 MPa, 1050 MPa, 1100 MPa, 1150 MPa, 1200 MPa, 1250 MPa, 1300 MPa, 1350 MPa, 1400 MPa, 1450 MPa, 1500 MPa, 1550 MPa, 1600 MPa, 1650 MPa, 1700 MPa, 1750 MPa, 1800 MPa, 1850 MPa, 1900 MPa, 1950 MPa, 2000 MPa, 2050 MPa, 2100 MPa, 2150 MPa, and 2200 MPa, a value equal to the above value, and / or a value between any two of the above values, measured in accordance with ISO 527. The tensile strength at yield of the polypropylene is 20 MPa to 40 MPa, or at least a value from 20 MPa, 25 MPa, 30 MPa, 35 MPa, and 40 MPa, a value equal to the above value, and / or a value between any two of the above values, measured in accordance with ASTM D638.

[0030] The notched Izod impact strength of the polypropylene component at 23°C is from 10 J / m to 30 J / m, or at least 10 J / m, 11 J / m, 12 J / m, 13 J / m, 14 J / m, 15 J / m, 16 J / m, 17 J / m, 18 J / m, 19 J / m, 20 J / m, 21 J / m, 22 J / m, 23 J / m, 24 J / m, 25 J / m, 26 J / m, 27 J / m, 28 J / m, 29 J / m, and 30 J / m, values equal to the above values, and / or values between any two of the above values, as measured according to ASTM D638.

[0031] The above polypropylene component is used as a polymer blend in combination with one or more different primary additives for use in high-frequency radio applications. These primary additives can impart a lower Dk, a lower Df, a higher metal adhesion strength, and a lower CTE to the polypropylene composition compared to polypropylene without the primary additive. The polypropylene composition can also exhibit high mechanical strength and good thermal performance.

[0032] The primary additive includes hollow glass bubbles. The glass bubbles serve to reduce the bulk density of the polypropylene and to lower the Dk value and the Df value. This is at least partially due to the presence of air, gas or a vacuum space within the glass bubbles, resulting in a lower Dk value and Df value for the glass bubbles themselves.

[0033] A glass bubble is typically a unicellular sphere that is a hollow, thin-walled structure made from soda lime borosilicate glass. The glass bubble may have an average diameter or particle size of 5 μm to 80 μm, more particularly 15 μm to 65 μm. In certain embodiments, the average diameter or particle size of the glass bubble is at least 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, and 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, 30 μm, 31 μm, 32 μm, 33 μm, 34 μm, 35 μm, 36 μm, 37 μm, 38 μm, 39 μm, 40 μm, 41 μm, 42 μm, 43 μm, 44 μm, 45 μm, 46 μm, 47 μm, 48 μm, 49 μm, 50 μm, 51 μm, 52 μm, 53 μm, 54 μm, 55 μm, 56 μm, 57 μm, 58 μm, 59 μm, 60 μm, 61 μm, 62 μm, 63 μm, 64 μm, 65 μm, 66 μm, 67 μm, 68 μm, 69 μm, 70 μm, 71 μm, 72 μm, 73 μm, 74 μm, 75 μm, 76 μm, 77 μm, 78 μm, 79 μm, and 80 μm, values equal to the above values, and / or values between any two of the above values.

[0034] The hollow glass bubbles may have a wall thickness of 0.4 μm to 1.5 μm, more particularly 0.5 μm to 0.9 μm, and even more particularly 0.6 μm to 0.8 μm. In certain embodiments, the wall thickness of the glass bubbles is at least 0.40 μm, 0.41 μm, 0.42 μm, 0.43 μm, 0.44 μm, 0.45 μm, 0.46 μm, 0.47 μm, 0.48 μm, 0.49 μm, 0.50 μm, 0.51 μm, 0.52 μm, 0.53 μm, 0.54 μm, 0.55 μm, 0.56 μm, 0.57 μm, 0.58 μm, 0.59 μm, 0.60 μm, 0.61 μm, 0.62 μm, 0.63 μm, 0.64 μm, 0.65 μm, 0.66 μm, 0.67 μm, 0.68 μm, 0.69 μm, 0.70 μm, 0.71 μm, 0.72 μm, 0.73 μm, 0.74 μm, 0.75 μm, 0.76 μm, 0.77 μm, 0.78 μm, 0.79 μm, 0.80 μm, 0.81 μm, 0.82 μm, 0.83 μm, 0.84 μm, 0.85 μm, 0.86 μm, 0.87 μm, 0.88 μm, 0.89 μm, 0.90 μm, 0.91 μm, 0.92 μm, 0.93 μm, 0.94 μm, 0.95 μm, 0.96 μm, 0.97 μm, 0.98 μm, 0.99 μm, 1.00 μm, 1.11 μm, 1.12 μm, 1.13 μm, 1.14 μm, 1.15 μm, 1.16 μm, 1.17 μm, 1.18 μm, 1.19 μm, 1.20 μm, 1.21 μm, 1.22 μm, 1.23 μm, 1.24 μm, 1.25 μm, 1.26 μm, 1.27 μm, 1.28 μm, 1.29 μm, 1.30 μm, 1.31 μm, 1.32 μm, 1.33 μm, 1.34 μm, 1.35 μm, 1.36 μm, 1.37 μm, 1.38 μm, 1.39 μm, 1.40 μm, 1.41 μm, 1.42 μm, 1.43 μm, 1.44 μm, 1.45 μm, 1.46 μm, 1.47 μm, 1.48 μm, 1.49 μm and 1.50 μm, values equal to the above values, and / or values between any two of the above values.

[0035] As a result, the gas amount or the internal space in the hollow glass sphere can be 50% to about 90%. Those glass bubbles having a gas amount or an internal space of 60% to 80% have been found to be particularly useful. In certain embodiments, the gas amount or the internal space in the hollow glass bubble can be at least 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, and values from 90%, values equal to the above values, and / or values between any two of the above values. The internal space of the glass bubble is usually filled with air, but may be filled with other gases such as nitrogen. Further, there may be no medium (vacuum) in the internal space, or it may be filled with a low dielectric constant liquid that is likely to reduce the Dk value and the Df value.

[0036] The glass bubbles may have a true density of 0.3 g / cc to 0.8 g / cc, as measured by helium pycnometry. In certain embodiments, the glass bubbles have a true density, as measured by helium pycnometry, of at least 0.30 g / cc, 0.31 g / cc, 0.32 g / cc, 0.33 g / cc, 0.34 g / cc, 0.35 g / cc, 0.36 g / cc, 0.37 g / cc, 0.38 g / cc, 0.39 g / cc, 0 g / cc, 0.41 g / cc, 0.42 g / cc, 0.43 g / cc, 0.44 g / cc, 0.45 g / cc, 0.46 g / cc, 0.47 g / cc, 0.48 g / cc, 0.49 g / cc, 0.50 g / cc, 0.51 g / cc, 0.52 g / cc, 0.53 g / cc, 0.54 g / cc, 0.55 g / cc, 0.56 g / cc, 0.57 g / cc, 0.58 g / cc, 0.59 g / cc, 0.60 g / cc, 0.61 g / cc, 0.62 g / cc, 0.63 g / cc, 0.64 g / cc, 0.65 g / cc, 0.66 g / cc, 0.67 g / cc, 0.68 g / cc, 0.69 g / cc, 0.70 g / cc, 0.71 g / cc, 0.72 g / cc, 0.73 g / cc, 0.74 g / cc, 0.75 g / cc, 0.76 g / cc, 0.77 g / cc, 0.78 g / cc, 0.79 g / cc, 0.80 g / cc, values equal to the above values, and / or values between any two of the above values.

[0037] Furthermore, the hollow glass bubbles may have a crushing strength of 30 MPa to 300 MPa. In certain embodiments, the crushing strength of the glass bubbles is at least 30 MPa, 31 MPa, 32 MPa, 33 MPa, 34 MPa, 35 MPa, 36 MPa, 37 MPa, 38 MPa, 39 MPa, 40 MPa, 41 MPa, 42 MPa, 43 MPa, 44 MPa, 45 MPa, 46 MPa, 47 MPa, 48 MPa, 49 MPa, 50 MPa, 51 MPa, 52 MPa, 53 MPa, 54 MPa, 55 MPa, 56 MPa, 57 MPa, 58 MPa, 59 MPa, 65 MPa, 66 MPa, 67 MPa, 68 MPa, 69 MPa, 70 MPa, 71 MPa, 72 MPa, 73 MPa, 74 MPa, 75 MPa, 76 MPa, 77 MPa, 78 MPa, 79 MPa, 80 MPa, 81 MPa, 82 MPa, 83 MPa, 84 MPa, 85 MPa, 86 MPa, 87 MPa, 88 MPa, 89 MPa, 90 MPa, 91 MPa, 92 MPa, 93 MPa, 94 MPa, 95 MPa, 96 MPa, 97 MPa, 98 MPa, 99 MPa, 100 MPa, 105 MPa, 110 MPa, 115 MPa, 120 MPa, 125 MPa, 130 MPa, 135 MPa, 140 MPa, 145 MPa, 150 MPa, 155 MPa, 160 MPa, 165 MPa, 170 MPa, 175 MPa, 180 MPa, 185 MPa, 190 MPa, 195 MPa, 200 MPa, 205 MPa, 210 MPa, 215 MPa, 220 MPa, 225 MPa, 230 MPa, 235 MPa, 240 MPa, 245 MPa, 250 MPa, 255 MPa, 260 MPa, 265 MPa, 270 MPa, 275 MPa, 280 MPa, 285 MPa, 290 MPa, 295 MPa, and values from 300 MPa, values equal to the above values, and / or values between any two of the above values.

[0038] Examples of suitable commercially available hollow glass bubbles include hollow glass bubbles available as 3M's iM16K and iM30K glass bubbles in Maplewood, Minnesota. The glass bubbles used in this study (IM30K high-strength glass bubbles) are commercially available from 3M (trademark). The average diameter of the glass bubbles was measured using a scanning electron microscope (SEM). The crushing strength and gas volume of the hollow glass bubbles were measured using 3M's internal QCM.

[0039] The hollow glass bubbles may be used in the polypropylene composition in an amount of 1 wt% to 35 wt% based on the total weight of the polypropylene composition. In certain embodiments, the glass bubbles are at least 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, and 35 wt% based on the total weight of the polypropylene composition, values equal to the above values, and / or values between any two of the above values.

[0040] During the melt-kneading of the polymer composition, a certain amount of the glass bubbles is expected to break. As a result, it is typical for less than 5% of the glass bubbles to break. The breakage of the glass bubbles should be minimized, but the broken glass bubbles essentially become glass powder and can promote the reinforcement of the polypropylene composition.

[0041] Since the glass bubbles and / or the broken glass bubbles do not provide sufficient reinforcement to the polypropylene composition by themselves, other materials may also be used in the polypropylene composition. This includes glass short fiber (SGF) materials, aluminum oxide fiber materials, cyclic olefin copolymers, and polycarbonate materials.

[0042] Glass fibers can be used to improve both the mechanical and thermal properties of polypropylene compositions. Such properties include higher rigidity, higher tensile or flexural modulus, lower CTE, higher heat distortion temperature (HDT), and better dimensional stability compared to polypropylene without such materials. Short glass fibers also have little effect on the dielectric properties of polymer compositions with glass bubbles by including glass fibers having a low Dk value (i.e., 4 - 5) and / or Df value (i.e., <0.005). Glass fibers may include aminosilane-treated glass fibers to facilitate dispersion in the polymer melt when used with maleic anhydride grafted polypropylene as a coupling agent.

[0043] The short glass fibers have a length of 0.5 mm to 10 mm and may have a width or diameter of 5 μm to 15 μm. In certain applications, the length of the short glass fibers may be a value from at least 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, 5.0 mm, 5.1 mm, 5.2 mm, 5.3 mm, 5.4 mm, 5.5 mm, 5.6 mm, 5.7 mm, 5.8 mm, 5.9 mm, 6.0 mm, 6.1 mm, 6.2 mm, 6.3 mm, 6.4 mm, 6.5 mm, 6.6 mm, 6.7 mm, 6.8 mm, 6.9 mm, and 7.0 mm, 7.1 mm, 7.2 mm, 7.3 mm, 7.4 mm, 7.5 mm, 7.6 mm, 7.7 mm, 7.8 mm, 7.9 mm, 8.0 mm, 8.1 mm, 8.2 mm, 8.3 mm, 8.4 mm, 8.5 mm, 8.6 mm, 8.7 mm, 8.8 mm, 8.9 mm, 9.0 mm, 9.1 mm, 9.2 mm, 9.3 mm, 9.4 mm, 9.5 mm, 9.6 mm, 9.7 mm, 9.8 mm, 9.9 mm, and 10.0 mm, a value equal to the above values, and / or a value between any two of the above values. The width or diameter of the short glass fibers may be a value from at least 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, and 15 μm, a value equal to the above values, and / or a value between any two of the above values.

[0044] The short glass fibers may be used in the polypropylene composition in an amount of 40% by weight or less based on the total weight of the polypropylene composition, and in many cases, 1% to 30% by weight based on the total weight of the polypropylene composition is preferred. In certain embodiments, the glass fibers are at least 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, and 40% by weight based on the total weight of the polypropylene composition, an amount equal to the above amount, and / or an amount between any two of the above amounts.

[0045] The polypropylene composition incorporating the short glass fibers may have a CTE of 35×10 -6 / °C or less as measured according to ASTM D696. In certain embodiments, the CTE value of the polypropylene composition incorporating the short glass fibers, measured according to ASTM D696, may be 35, 30, 25, 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5×10 -6 / °C or less.

[0046] In certain applications, since both low Dk and Df values and high Dk and Df values provide a similar reinforcing effect to the polypropylene composition, the short glass fibers may be short glass fibers having higher or lower Dk and Df values. When used, the short glass fibers having higher Dk and Df values may be short glass fibers having a Dk value measured at 6 MHz or higher according to ASTM D150 of 5 or more and a dielectric tangent Dk measured at 6 MHz or higher according to ASTM D150 of greater than 0.005. The glass fibers may include E-CR (E-glass corrosion resistant) glass fibers. Examples of such commercially available short glass fibers include glass fibers available as DS2200 13P glass fibers from the Braj Binani Group in Mumbai, India. These glass fibers are distinguishable from glass fibers having low Dk and Df values.

[0047] Glass fibers with low permittivity or Dk value and Df value may also be used alone or in combination with glass short fibers having higher Dk value and Df value. The low Dk glass fibers may be glass fibers having a Dk value of 4 to 5 measured at 6 MHz or higher in accordance with ASTM D150. In certain embodiments, the low Dk glass fibers may have a Dk value of at least 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, and 5.0, a Dk value equal to the above values, and / or a Dk value between any two of the above values. Glass fibers with low Df may be glass fibers having a Df value of 0.005, 0.004, 0.003, 0.002, 0.001, 0.0009, 0.0008, 0.0007, 0.0006, 0.0005, 0.0004, 0.0003, 0.0002, 0.0001 or less. Glass fibers with low Dk and Df may have one or both of low Dk and low Df. Typically, fibers with low Dk and Df have both low Dk and low Df. The glass fibers may include HL-glass fibers. Examples of such commercially available glass short fibers with low Dk value and Df value include glass short fibers available as CS(HL)303N-3 glass fibers from Chongqing Polycomp International Corp in Chongqing, China.

[0048] The glass fibers having a low Dk and a low Df may constitute all or part of all the glass staple fibers. The glass fibers having a low Dk and a low Df may be present in the polypropylene composition in an amount of 40% by weight or less based on the total weight of the polypropylene composition. In certain embodiments, when used, the glass fibers having a low Dk and a low Df are, based on the total weight of the polypropylene composition, at least 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39% and 40% by weight, an amount equal to the above amount, and / or an amount between any two of the above amounts.

[0049] Aluminum oxide fibers may be used in polypropylene compositions. The aluminum oxide fibers improve mechanical properties such as tensile modulus and stiffness while maintaining radio frequency (RF) permeability. The aluminum oxide fibers may be any form of aluminum oxide phase and may be obtained using any suitable process. The aluminum oxide fibers may generally be in a cylindrical shape and / or a flat shape. The length of the aluminum oxide fibers may range from 1 mm to 10 mm, and the diameter or width may range from 1 μm to 15 μm. In certain applications, the length of the aluminum oxide fibers may be at least 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, 5.0 mm, 5.1 mm, 5.2 mm, 5.3 mm, 5.4 mm, 5.5 mm, 5.6 mm, 5.7 mm, 5.8 mm, 5.9 mm, 6.0 mm, 6.1 mm, 6.2 mm, 6.3 mm, 6.4 mm, 6.5 mm, 6.6 mm, 6.7 mm, 6.8 mm, 6.9 mm, and values from 7.0 mm, 7.1 mm, 7.2 mm, 7.3 mm, 7.4 mm, 7.5 mm, 7.6 mm, 7.7 mm, 7.8 mm, 7.9 mm, 8.0 mm, 8.1 mm, 8.2 mm, 8.3 mm, 8.4 mm, 8.5 mm, 8.6 mm, 8.7 mm, 8.8 mm, 8.9 mm, 9.0 mm, 9.1 mm, 9.2 mm, 9.3 mm, 9.4 mm, 9.5 mm, 9.6 mm, 9.7 mm, 9.8 mm, 9.9 mm, and 10.0 mm, values equal to the above values, and / or values between any two of the above values. The width or diameter of the aluminum oxide fibers may be at least values from 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, and 15 μm, values equal to the above values, and / or values between any two of the above values.Examples of such commercially available aluminum oxide fibers include aluminum oxide fibers available as 3M's Nextel 610 fiber in Maplewood, Minnesota.

[0050] The aluminum oxide fibers may be present in the polypropylene composition in an amount of 40 wt% or less based on the total weight of the polypropylene composition. When used, in certain embodiments, the aluminum oxide fibers are present in an amount of at least 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, 35 wt%, 36 wt%, 37 wt%, 38 wt%, 39 wt% and 40 wt% based on the total weight of the polypropylene composition, an amount equal to the above amount, and / or an amount between any two of the above amounts.

[0051] Cyclic olefin copolymers may also be used in the polypropylene composition. Particularly useful are olefin-norbornene copolymers containing comonomers such as 8,9,10-trinorbornene-2-ene (norbornene) or 1,2,3,4,4a,5,8,8a-octahydro-1,4:5,8-dimethanonaphthalene (tetracyclododecene). Cyclic olefin copolymers have low Dk and Df values at frequencies above 2 GHz. Therefore, their inclusion helps to provide lower Dk and Df values to the polypropylene composition. Also, cyclic olefin copolymers help to reduce warping and further lower the CTE to improve the heat resistance performance of the polypropylene composition. Cyclic olefin copolymers are fully aliphatic polymers that are miscible and / or form a co-continuous morphology when blended with polypropylene during extrusion. An example of a suitable cyclic olefin copolymer is a cyclic olefin copolymer available as TOPAS® 6017 cyclic olefin copolymer from TOPAS Advanced Polymers GmbH (Rauenheim, Germany), which has a heat distortion temperature (HDT) of 170 °C.

[0052] The cyclic olefin copolymer may be used in an amount of 20 wt% or less based on the total weight of the polypropylene composition. When used, in certain embodiments, the cyclic olefin copolymer is at least 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt% and 20 wt% based on the total weight of the polypropylene composition, an amount equal to the above amount, and / or an amount between any two of the above amounts.

[0053] Polycarbonate can also be used in the polypropylene composition. The weight average molecular weight of the polycarbonate inferred from gel permeation chromatography is in the range of 30,000 to 60,000 based on polystyrene. As inferred from NMR analysis, the polycarbonate is almost completely end-capped. The polycarbonate can improve metal adhesion and reduce warping. Examples of the polycarbonate include, but are not limited to, bisphenol A polycarbonate and copolycarbonates obtained by varying the ratios of different comonomers (e.g., 20% to 50%). Particularly useful is bisphenol A polycarbonate.

[0054] The polycarbonate may be used in an amount of 20% by weight or less based on the total weight of the polypropylene composition. When used, in certain embodiments, the polycarbonate may be used in an amount of at least 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, and 20% by weight based on the total weight of the polypropylene composition, an amount equal to the above amounts, and / or an amount between any two of the above amounts.

[0055] Polyvinylcyclohexane (PVCH) and poly(1,4-cyclohexylidene cyclohexane-1,4-dicarboxylate) (PCCD) can also be used in the polypropylene composition. PCCD may be obtained by a melt polycondensation reaction of 1,4-cyclohexanedimethanol (CHDM) and 1,4-cyclohexanedicarboxylic acid (CHDA). PVCH may be obtained by the polymerization of vinylcyclohexane or the catalytic reduction of polystyrene. These materials help to reduce warpage, lower the CTE, and improve the thermal performance. The glass transition temperature of PVCH is about 145 °C. These materials are miscible when blended with polypropylene during extrusion and are all-aliphatic polymers that form a co-continuous morphology.

[0056] PVCH and PCCD may be used in an amount of 20 wt% or less based on the total weight of the polypropylene composition. When used, in certain embodiments, PVCH and PCCD or a combination thereof may be at least 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, and amounts from 20 wt%, amounts equal to the above amounts, and / or amounts between any two of the above amounts based on the total weight of the polypropylene composition.

[0057] The polypropylene composition or polymer blend formed during melt compounding can further include at least one additional secondary additive that is distinct from the primary additives described above. The optional or secondary additive may be an additive that does not necessarily affect or increase the dielectric properties (i.e., Dk value and Df value), mechanical properties, or thermal properties of the final product, but there is a possibility of affecting or increasing them. The optional or secondary additive may be added to facilitate processing during the melt compounding and extrusion steps, but it may also impart various desired properties to the final polypropylene composition. Non-limiting examples of additional optional or secondary additives include stabilizers, coupling agents, compatibilizers, thermal conductivity agents, flame retardant additives, thermal conductivity additives, binders, antiblocking agents, antistatic agents, antioxidants, neutralizing agents, acid scavengers, foaming agents, nucleating agents, crystallization aids, dyes, flame retardants, fillers, hard fillers, soft fillers, impact modifiers, mold release agents, oils, other polymers, pigments, processing agents, reinforcing agents, light stabilizers, UV resistant agents, lubricants, flow improvers, and combinations thereof.

[0058] To achieve a good interface between the glass fiber and the polypropylene component and enable uniform dispersion, a coupling agent may be blended into the polymer blend. The coupling agent may be maleic anhydride grafted polypropylene (MA-g-PP). The coupling is carried out in situ in the extruder. When this coupling agent is used, the interaction between the maleic anhydride groups and amino groups of the aminosilane-treated glass fiber promotes the dispersion of the glass fiber. Examples of coupling agents suitable for polypropylene include maleic anhydride grafted polypropylene (MA-g-PP) available as ExxonMobil's Exxelor™ PO 1020. The coupling agent may be present in the polymer blend in an amount of 2 wt% or less based on the total weight of the polymer blend. In certain embodiments, when used, the coupling agent is used in an amount of at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1.0 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt%, and 2.0 wt% based on the total weight of the polymer blend, an amount equal to the above amount, and / or an amount between any two of the above amounts.

[0059] In some cases, the thermal conductivity additive is present in the polymer blend in an amount of at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, and 1.0 wt% based on the total weight of the polymer blend, an amount equal to the above amount, and / or an amount between any two of the above amounts. Non-limiting examples of thermal conductivity additives include aluminum oxide, titanium dioxide, graphite compounds, graphene, boron nitride, aluminum nitride, zinc oxide, and the like.

[0060] In some embodiments, the filler is present in the polymer blend in an amount from at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1.0 wt%, 2.0 wt%, 3.0 wt%, 4.0 wt%, 5.0 wt%, 6.0 wt%, 7.0 wt%, 8.0 wt%, 9.0 wt%, 10.0 wt%, 20.0 wt%, 30.0 wt% based on the total weight of the polymer blend, an amount equal to the above amount, and / or an amount between any two of the above amounts. The filler can be a hard filler. Non-limiting examples of hard fillers include inorganic particulate fillers such as talc, silica, calcium carbonate, and inorganic layered fillers such as clay, mica, and the like. The filler can be a soft filler. Non-limiting examples of soft fillers include immiscible particulate elastomer / polymer resins. The filler can also be a hollow filler. Non-limiting examples of hollow fillers include plastic microspheres, ceramic microspheres such as cenospheres made from aluminosilicate microspheres, metal microspheres made from aluminum and copper / silver microspheres, and phenolic microspheres.

[0061] In certain embodiments, the light stabilizer is present in the polymer blend in an amount from at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, and 1.0 wt% based on the total weight of the polymer blend, an amount equal to the above amounts, and / or an amount between any two of the above amounts. The light stabilizer can be a hindered amine light stabilizer. The term "hindered amine light stabilizer" refers to a group of amine compounds having specific light stabilizing properties. Non-limiting examples of hindered amine light stabilizers (HALS) include 1-cyclohexyloxy-2,2,6,6-tetramethyl-4-octadecylaminopiperidine; bis(2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(1-acetoxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(1,2,2,6,6-pentamethylpiperidin-4-yl) sebacate; bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(1-acyl-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(1,2,2,6,6-pentamethyl-4-piperidyl) n-butyl-3,5-di-tert-butyl-4-hydroxybenzyl malonate; 2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) butylamino]-6-(2-hydroxyethylamino-s-triazine; bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) adipate; 2,4-bis[(1-cyclohexyloxy-2,2,6,6-piperidin-4-yl) butylamino]-6-chloro-s-triazine; 1-(2-hydroxy-2-methylpropoxy)-4-hydroxy-2,2,6,6-tetramethylpiperidine; 1-(2-hydroxy-2-methylpropoxy)-4-oxo-2,2,6,6-tetramethylpiperidine; 1-(2-hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine;Bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; Bis(1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl) adipate; 2,4-Bis{N-[1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl]-N-butylamino}-6-(2-hydroxyethylamino)-s-triazine; 4-Benzoyl-2,2,6,6-tetramethylpiperidine; Di-(1,2,2,6,6-pentamethylpiperidin-4-yl) p-methoxybenzylidenemalonate; 2,2,6,6-Tetramethylpiperidin-4-yl octadecanoate; Bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl) succinate; 1,2,2,6,6-Pentamethyl-4-aminopiperidine; 2-Undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4,5]decane; Tris(2,2,6,6-tetramethyl-4-piperidyl) nitrilotriacetate; Tris(2-hydroxy-3-(amino-(2,2,6,6-tetramethylpiperidin-4-yl)propyl) nitrilotriacetate; Tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butane-tetracarboxylate; Tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butane-tetracarboxylate; 1,1’-(1,2-Ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone); 3-n-Octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione; 8-Acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione; 3-Dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)pyrrolidine-2,5-dione; 3-Dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione; N,N’-Bis-formyl-N,N’-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine;Reaction product of 2,4-bis[(1-cyclohexyloxy-2,2,6,6-piperidin-4-yl)butylamino]-6-chloro-s-triazine and N,N'-bis(3-aminopropyl)ethylenediamine; condensate of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid; condensate of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine; condensate of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine; condensate of N,N'-bis-(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine; condensate of N,N'-bis-(1,2,2,6,6-pentamethyl-4-piperidyl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine; condensate of 2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane; condensate of 2-chloro-4,6-di-(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine and 1,2-bis-(3-aminopropylamino)ethane; reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro[4,5]decane and epichlorohydrin; poly[methyl,(3-oxy-(2,2,6,6-tetramethylpiperidin-4-yl)propyl)]siloxane, CAS#182635-99-0; reaction product of maleic anhydride-C18-C22-α-olefin-copolymer and 2,2,6,6-tetramethyl-4-aminopiperidine; oligomeric condensate of 4,4'-hexamethylenebis(amino-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6-bis(dibutylamino)-s-triazine;Oligomeric condensates of 4,4'-hexamethylenebis(amino-1,2,2,6,6-pentamethylpiperidine) and 2,4-dichloro-6-[(1,2,2,6,6-pentamethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6-bis(dibutylamino)-s-triazine; oligomeric condensates of 4,4'-hexamethylenebis(amino-1-propoxy-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(1-propoxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6-bis(dibutylamino)-s-triazine; oligomeric condensates of 4,4'-hexamethylenebis(amino-1-acryloyloxy-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(1-acryloyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6-bis(dibutylamino)-s-triazine; and products obtained by reacting (a) and (b), wherein (a) is a product obtained by reacting 1,2-bis(3-aminopropylamino)ethane with cyanuric chloride, and (b) is (2,2,6,6-tetramethylpiperidin-4-yl)butylamine; also included are sterically hindered N-H, N-methyl, N-methoxy, N-hydroxy, N-propoxy, N-octyloxy, N-cyclohexyloxy, N-acryloyloxy and N-(2-hydroxy-2-methylpropoxy) analogs of any of the above compounds. Non-limiting examples of commercially available light stabilizers are available under the trade names Uvinul® 4050H, 4077H, 4092H, 5062H, 5050H, 4092H, 4077H, 3026, 3027, 3028, 3029, 3033P, and 3034 from BASF or Tinuvin® 622;

[0062] The antistatic agent can be used to suppress the accumulation of dust on plastic articles. The antistatic agent can improve the electrical conductivity of the plastic composition and eliminate any surface charges generated during manufacturing and use. Therefore, dust particles are less likely to be attracted to the surface of the plastic article, and as a result, the accumulation of dust is reduced. In a particular embodiment of the present invention, the antistatic agent can be glycerol monostearate. The polymer blend may contain the antistatic agent in an amount from at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, and 1 wt% based on the total weight of the polymer blend, an amount equal to the above amount, and / or an amount between any two of the above amounts.

[0063] To improve the mold manufacturing characteristics, a lubricant can be added to the polymer blend. The lubricant can be a low molecular weight compound from the group of fatty acids, fatty acid esters, wax esters, fatty alcohol esters, amide waxes, metal carboxylates, montanic acids, montanic acid esters, or a high molecular weight compound such as paraffin or polyethylene wax. In a particular embodiment of the present invention, the lubricant is a metal stearate. Non-limiting examples of metal stearates include zinc stearate, calcium stearate, lithium stearate, or combinations thereof, preferably calcium stearate. The polymer blend may contain the lubricant in an amount from at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, and 1 wt% based on the total weight of the polymer blend, an amount equal to the above amount, and / or an amount between any two points of the above amounts.

[0064] Antioxidants and / or heat stabilizers can provide protection against polymer degradation during processing. Phosphites are known as heat-oxidation stabilizers for polymers and other organic materials. The antioxidant can be a phosphite-based antioxidant. In certain embodiments, phosphite-based antioxidants include, but are not limited to, triphenyl phosphite, diphenyl alkyl phosphite, phenyl dialkyl phosphite, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, tristearyl sorbitol triphosphite, and tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, bis(2,4-dicumylphenyl) pentaerythritol diphosphite. The polymer blend can contain the antioxidant in an amount of at least 0.01 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, and amounts from 0.1 wt%, an amount equal to the above amounts, and / or an amount between any two of the above amounts, based on the total weight of the polymer blend. Non-limiting examples of commercially available antioxidants or heat stabilizers include Irganox 1010 and Irgaphos-168 available from BASF, or Doverphos S9228T available from Dover Chemical Company.

[0065] Nucleating agents may also be used in the polymer blend. The nucleating agent may be considered as an additive added to the polymer to promote crystal growth in the polymer melt. One or more nucleating agents may be used. The nucleating agent may include, but is not limited to, cyclic dicarboxylates and talc. Talc is often used as a filler when used in large amounts. Talc acts as a nucleating agent when used in a low amount (i.e., <5 wt%). The use of a combination of a cyclic dicarboxylate as the first nucleating agent and talc as the second nucleating agent is described in U.S. Patent No. 11,136,446, which is incorporated herein by reference for all purposes. When using such a combination, the nucleating agent may be used in various amounts. For example, the weight ratio of the cyclic dicarboxylate to talc may range from 1:1200 to 2:1. The cyclic dicarboxylate may be used in an amount of 0.0025 wt% to 0.1 wt% based on the total weight of the composition, and the talc nucleating agent may be used in an amount of 0.1 wt% to 5 wt%. Examples of suitable commercially available potassium salts of 1,2-cyclohexanedicarboxylic acid useful as nucleating agents include the potassium salt available as HYPERFORM® HPN 20E from Milliken and Company.

[0066] When forming the polypropylene composition, the various components of the polypropylene composition containing the primary additives described can be dry blended with any additional secondary additives. The polypropylene component may be in the form of pellets, powder, flakes or fluff. The materials are mixed in a conventional mixer, and the polypropylene and primary additives are mixed with any additional additives or secondary additives. Any secondary additives can be added at the end or during the processing steps for producing the polymer blend. Suitable machinery for such mixing is known to those skilled in the art. Non-limiting examples include mixers, kneaders and extruders. These materials are then fed directly into the feed zone of an extruder. In certain cases, the process can be carried out in an extruder and the introduction of additives may occur during processing. Non-limiting examples of suitable extruders include single-screw extruders, counter-rotating and co-rotating twin-screw extruders, planetary gear extruders, ring extruders, or compounding kneaders. The process can be carried out at a temperature of 180°C to 300°C.

[0067] In some embodiments, the polypropylene component, primary additives, and any secondary additives used to produce the polypropylene polymer blend of the present invention can be melt extruded according to a typical procedure of weighing the required amounts of polypropylene and additives, then dry blending, and then feeding the mixture into the main feeder of a single-screw or co-rotating twin-screw extruder (length / diameter (L / D) ratio of 25:1 or 40:1) to obtain the final composition. The polypropylene, additives, or blends thereof can be subjected to high temperature for a sufficient time in the blend. The blend temperature can be a temperature above the melting point of the polymer. In certain embodiments, the extrusion process can be carried out at a temperature of 180°C to 300°C. The primary and secondary additives can be added inline, before pelletization of the polypropylene resin during the manufacturing process. The amount of additives combined with the polypropylene can be adjusted to provide the weights described previously.

[0068] Any secondary additive can be premixed with the polymer blend or its various components or added individually. As an example, by premixing the secondary additives of the present invention, a blend can be formed prior to addition to the polypropylene or primary additives. The blend can be subjected to high temperature for a sufficient time during blending of the additives and / or compounding. Incorporation of any secondary additive into the polymer resin can be carried out, for example, by mixing the above-described components using methods conventional in the process art. The temperature for blending can be a temperature exceeding the melting point of the polypropylene polymer. In a particular embodiment, the process can be carried out at a temperature of 180 °C to 260 °C. By such "melt-kneading" or "melt-mixing", the optional additive is uniformly dispersed in the polypropylene and / or primary additives.

[0069] Articles manufactured from the polypropylene composition prepared as described can be used in high-frequency radio wave applications above 6 GHz. In particular, the polypropylene and / or articles molded therefrom may have a Dk value of 2.5, 2.4, 2.3, 2.2, 2.1, or 2.0 or less when measured at 6 GHz or above. Also, the polypropylene and / or articles molded therefrom may have a Df value of 0.005, 0.004, 0.003, 0.002, 0.001, 0.0005 or less when measured at 6 GHz or above.

[0070] Furthermore, the polypropylene composition and / or an article molded therefrom may have a metal adhesion peel strength measured in accordance with ASTM B533 or IPC-TM-650 of 0.1 N / mm, 0.2 N / mm, 0.3 N / mm, 0.4 N / mm, 0.5 N / mm, 0.6 N / mm, 0.7 N / mm, 0.8 N / mm, 0.9 N / mm, 1.0 N / mm or more. In certain embodiments, the metal adhesion peel strength measured in accordance with ASTM B533 or IPC-TM-650 is at least 0.1 N / mm, 0.2 N / mm, 0.3 N / mm, 0.4 N / mm, 0.5 N / mm, 0.6 N / mm, 0.7 N / mm, 0.8 N / mm, 0.9 N / mm, 1.0 N / mm, 1.1 N / mm, 1.2 N / mm, 1.3 N / mm, 1.4 N / mm, and values from 1.5 N / mm, values equal to the above values, and / or values between any two of the above values.

[0071] The polypropylene composition or an article formed therefrom may have a CTE measured in accordance with ASTM D696 of 35 ppm / °C, 30 ppm / °C, 25 ppm / °C, 20 ppm / °C, 15 ppm / °C, 10 ppm / °C or less. Furthermore, the polypropylene composition and / or an article formed therefrom may have a HDT measured in accordance with ASTM D648 of 110 °C, 120 °C, 130 °C, 140 °C, 150 °C or more.

[0072] Also, the polypropylene composition or article may have a water absorption rate measured in accordance with ASTM D570 of 0.05 wt%, 0.04 wt%, 0.03 wt%, 0.02 wt%, 0.01 wt% or less based on the total weight. The above composition or article may also have a tensile modulus measured in accordance with ASTM D638 of 2000 MPa, 2100 MPa, 2200 MPa, 2300 MPa, 2400 MPa, 2500 MPa or more, and a tensile strength measured in accordance with ASTM D638 of 35 MPa, 40 MPa, 45 MPa, 50 MPa, 55 MPa, 60 MPa or more.

[0073] The polypropylene composition may have a density of 1.4 g / cc, 1.3 g / cc, 1.2 g / cc, 1.1 g / cc, 1.0 g / cc, 0.9 g / cc or less. Further, the composition may have a UL94 flame retardant grade of V0 @ 1.5 mm and a thermal conductivity of 0.10 W / mK, 0.15 W / mK, 0.20 W / mK, 0.25 W / mK, 0.30 W / mK, 0.35 W / mK, 0.40 W / mK, 0.45 W / mK, 0.5 W / mK or less as measured according to ASTM C518.

[0074] The polypropylene composition may be useful for specific applications at service temperatures from -40°C to 125°C or higher.

[0075] The polypropylene composition formed as described is usually recovered as pellets, which can be stored for some time or used immediately in the molding process. Examples of the molding process include injection molding, blow molding, compression molding, sheet extrusion, film blowing, pipe extrusion, profile extrusion, calender molding, thermoforming, rotomolding, or combinations thereof. The finally formed polypropylene article can be an article used in high-frequency radio wave applications of 6 GHz or higher. Examples of these articles include, for example, telecommunication equipment or components, high-frequency (>6 GHz) electrical equipment, high-frequency (>6 GHz) multi-generation telecommunication equipment or components, electrical communication antennas and end-use equipment or components of 5G or higher generations, telecommunication equipment housings, radome covers, high-frequency (RF) filters, RF connectors, EMI shields, antenna substrates, waveguide substrates or carriers, antenna substrates of base station antennas, and automotive radar components.

[0076] The following examples serve to further illustrate various embodiments and applications.

Examples

[0077] 〔Example 1〕 In order to provide a polypropylene composition suitable for use in high-frequency radio wave applications above 6 GHz, polypropylene was modified by combining glass bubbles with various different additives. The polypropylene composition was prepared using SABIC® PP571 polypropylene, which is an isotactic polypropylene homopolymer having the properties shown in Table 1 below. [Table 1]

[0078] Various additives were used in the PP571 polypropylene to improve its dielectric, mechanical, and thermal properties. The hollow glass bubbles used were hollow glass bubbles available as iM30K glass bubbles formed from soda lime borosilicate glass, having an average diameter of 18 μm, a true density of 0.60 g / cc, and a crushing strength of 18.6 MPa. The low dielectric constant glass fibers (low Dk-Df) were glass fibers available as CS(HL)303N-3 glass fibers, having an average length of 3 mm, an average diameter of 13 μm, a Dk value of 4.2 to 4.8, and a Df value <0.001. The polycarbonate (PC) was bisphenol A polycarbonate. The coupling agent was MA-g-PP.

[0079] For comparison, neat PP571 polypropylene without additives was also extruded and tested. The melt kneading of the various mixtures was carried out using a Coperion ZSK-25mm twin-screw extruder having an L / D ratio of 40:1, 10 barrels, and a co-rotating screw. The temperature profile used during extrusion is shown in Table 2 below. [Table 2]

[0080] The following Tables 3 and 4 show the details of the formulations of the control examples and the working examples (WE), as well as the mechanical, thermal, and dielectric properties of these formulations, respectively. [Table 3]

Table 4

[0081] When the properties of Example WE-1 containing 10 wt% glass bubbles were compared with those of a control example without additives to improve performance, with the addition of 10 wt% glass bubbles, the tensile modulus increased by about 20% and the CTE decreased by about 9%, while other properties were almost maintained. When low Dk glass fibers were incorporated in Example WE-2, a relatively large reinforcing effect and a significant impact on thermal and heat properties were revealed. Mechanical properties such as tensile modulus, tensile strength, and impact strength increased on average by about 163%, 130%, and 335%, respectively, and the heat distortion temperature (HDT) increased by about 150%. Incorporation of low Dk glass fibers significantly decreased the CTE (by about 135%), while the dielectric properties (Dk and Df) were hardly affected. The Dk value and Df value of polypropylene increased slightly with the incorporation of low Dk glass fibers, but when conventional short glass fibers were incorporated as a reinforcing filler in the same loading amount, a much higher increase in the Dk value and Df value was observed. When both glass bubbles and low Dk glass fibers were used in combination, a better reinforcing effect was obtained (as evident from the increase in modulus), and the CTE also decreased slightly (comparison between Example WE-5 and the control example). The incorporation of PC had no significant effect on the properties of polypropylene compositions containing low Dk glass fibers (comparison between Example WE-2 and Example WE-3), as well as polypropylene compositions containing both low Dk glass fibers and glass bubbles (comparison between Example WE-2 and Example WE-4). From preliminary metal plating experiments, the metal adhesiveness of these compositions was improved.

[0082] Although the present invention has been shown in several aspects, it will be apparent to those skilled in the art that the invention is not so limited, and various changes and modifications can be made without departing from the scope of the invention based on other optimizations considering experimental data or the economy of the overall process. Therefore, the appended claims should be construed broadly and appropriately so as not to conflict with the scope of the present invention.

Claims

1. Polypropylene and Hollow glass bubbles with an average diameter or particle size of 5 μm to 80 μm, A polypropylene composition for use in high-frequency radio wave applications of 6 GHz or higher, comprising a mixture of at least one glass fiber having a length of 0.5 mm to 10 mm and a width or diameter of 5 μm to 15 μm, an aluminum oxide fiber having a length of 1 mm to 5 mm and a width or diameter of 1 μm to 30 μm, a cyclic olefin copolymer, and polycarbonate.

2. The composition according to claim 1, wherein the composition contains the above-mentioned hollow glass bubbles in an amount of 1% to 35% by weight.

3. The composition according to claim 1, wherein the hollow glass bubble has at least one of the following: Crushing strength of 30 MPa or more, as measured by QCM; True density of 0.3 g / cc to 0.8 g / cc as measured by helium pycnometry; and, The amount of gas between 50% and 90%, as measured by QCM.

4. The composition according to claim 1, wherein the composition contains the glass fibers in an amount of 40% by weight or less relative to the total weight of the composition.

5. The composition according to claim 1, wherein the above glass fibers have at least one of the following: Dielectric constant (Dk) of 4 or greater, measured at 6 MHz or above according to ASTM D150. Dielectric loss tangent (Df) of 0.005 or less, measured at 6 MHz or above according to ASTM D150, and Measured according to ASTM D696, 35 × 10 －６ The coefficient of thermal expansion (CTE) of less than or equal to 1°C.

6. The composition according to claim 1, wherein the composition contains aluminum oxide fibers in an amount of 40% by weight or less relative to the total weight of the composition.

7. The above polypropylene is C ２ and C ４ ~C １０ A copolymer having a comonomer selected from olefin monomers, The composition according to claim 1, wherein the above-mentioned comonomer is present in the copolymer in an amount of 15% by weight or less.

8. The composition according to claim 1, wherein the composition comprises a cyclic olefin copolymer in an amount of 20% by weight or less relative to the total weight of the composition.

9. The composition according to claim 1, wherein the composition contains polycarbonate in an amount of 20% by weight or less relative to the total weight of the composition.

10. The composition according to claim 1, further comprising at least one of polyvinylcyclohexane and poly(1,4-cyclohexylidenecyclohexane-1,4-dicarboxylate).

11. The composition according to claim 1, further comprising at least one of the following: stabilizers, coupling agents, compatibilizers, thermal conductive agents, flame retardant additives, thermal conductive additives, binders, antiblocking agents, antistatic agents, antioxidants, neutralizing agents, acid scavengers, foaming agents, nucleating agents, crystallization aids, dyes, flame retardants, fillers, hard fillers, soft fillers, impact modifiers, release agents, oils, other polymers, pigments, processing agents, reinforcing agents, light stabilizers, UV resistant agents, lubricants, flow modifiers, and combinations thereof.

12. The above polypropylene composition has a Dk value of 2.5 or less when measured at 6 GHz or higher, a Df value of 0.005 or less when measured at 6 GHz or higher, and has at least one of the following, according to any one of claims 1 to 11: Metal adhesive peel strength of 0.1 N / mm or greater, as measured according to ASTM B533 or IPC-TM-650; A coefficient of thermal expansion (CTE) of 60 ppm / °C or less, measured according to ASTM D696; Heat distortion temperature (HDT) of 100°C or higher, as measured according to ASTM D648; Water absorption rate of 0.05% by weight or less, as measured according to ASTM D570; Tensile modulus of 2000 MPa or greater, as measured according to ASTM D638; Tensile strength of 35 MPa or greater, as measured according to ASTM D638; Density of 1.4 g / cc or less; V0@1.5mm UL94 flame retardant grade; and, Thermal conductivity of 0.2 W / mK or greater, measured according to ASTM C518.

13. The composition according to any one of claims 1 to 11, wherein the polypropylene composition is molded into a manufactured article.

14. The composition according to claim 13, wherein the manufactured article is at least one of the following: telecommunications equipment or components, high-frequency (>6GHz) electrical equipment, high-frequency (>6GHz) multi-generation telecommunications equipment or components, telecommunications antennas and end-use equipment or components of 5G or higher generations, telecommunications equipment housings, radome covers, high-frequency (RF) filters, RF connectors, EMI shields, antenna substrates, waveguide substrates or carriers, antenna substrates for base station antennas, or automotive radar components.

15. Hollow glass bubbles with an average diameter or particle size of 5 μm to 80 μm, A material comprising glass fibers having a length of 0.5 mm to 10 mm and a width or diameter of 5 μm to 15 μm, aluminum oxide fibers having a length of 1 mm to 5 mm and a width or diameter of 1 μm to 15 μm, a cyclic olefin copolymer, and at least one of polycarbonate, By melt-kneading with polypropylene, the polypropylene is modified, thereby dispersing the above material throughout the polypropylene. A method for forming a polypropylene composition for use in high-frequency radio wave applications of 6 GHz or higher, including [the specified element].