Polyamide / Polyolefin Blends and Corresponding Components for Portable Electronic Devices

Abstract

Described herein is a polymer composition comprising a functionalized polyolefin, an aliphatic polyamide, and a glass fiber, wherein the weight ratio of the functionalized polyolefin to the total weight of the aliphatic polyamide and the functionalized polyolefin in the polymer composition ("polyolefin weight ratio") is 55% to 95%. Surprisingly, it has been discovered that the polymer composition has superior dielectric performance and improved mechanical performance relative to corresponding polymer compositions. Due to the superior dielectric performance and improved mechanical performance, the polymer composition may be desirably incorporated into portable electronics applications.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 857470, filed June 5, 2019, and European Patent Application Publication No. 19198882.3, filed September 23, 2019, the entire contents of each of which are incorporated herein by reference for all purposes.

[0002] The present invention relates to a polymer composition comprising a functionalized polyolefin, an aliphatic polyamide, and glass fibers, the polymer composition having excellent dielectric and mechanical performance. The present invention also relates to a component of a portable electronic device comprising the polymer composition. [Background technology]

[0003] Polyamide compositions are widely used in portable electronic components due to their reduced weight and high mechanical performance.In particular, polyamide polymer compositions containing glass fibers are particularly suitable for portable electronic applications.Such compositions can have suitable mechanical strength, reduced weight and increased design options, making them attractive as metal replacements in portable electronic components. Summary of the Invention

[0004] In a first aspect, the present invention provides a polymer composition comprising a functionalized polyolefin, an aliphatic polyamide, glass fibers, and a functionalized polyolefin weight ratio of 55% to 95%, wherein the functionalized polyolefin weight ratio is represented by the formula: TIFF0007635160000001.tif12170, and W PA and W PO are the weights of aliphatic polyamide and functionalized polyolefin in the polymer composition, respectively.

[0005] In some embodiments, the polymeric composition has a tensile strength of at least 83 MPa. Additionally or alternatively, in some embodiments, the polymeric composition has a tensile strain of at least 2.8%. Additionally or alternatively, in some embodiments, the polymeric composition has a tensile modulus of at least 7.8 GPa. In some embodiments, the polymeric composition has a D @ 1 MHz of 3.1 or less. k and D at 1 MHz of 0.007 or less f has.

[0006] In another aspect, the invention relates to a component of a portable electronic device comprising the polymer composition, hi some embodiments, the portable electronic device is a housing for the portable electronic device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Described herein is a polymer composition comprising a functionalized polyolefin, an aliphatic polyamide, and a glass fiber, wherein the weight ratio of the functionalized polyolefin to the total weight of the aliphatic polyamide and the functionalized polyolefin in the polymer composition ("polyolefin weight ratio") is 55%-95%. Surprisingly, it has been discovered that the polymer composition has superior dielectric performance and improved mechanical performance relative to the corresponding polymer composition. As used herein, the polymer composition and the corresponding polymer composition are identical except for the fact that the weight ratio of the polyolefin in the corresponding polymer composition is outside the range of 55%-95%. More specifically, the polyolefin weight ratio of the corresponding polymer composition is less than 55%, preferably 50% or less, or greater than 95%, preferably 99% or more. Due to the superior dielectric performance and improved mechanical performance, the polymer composition may desirably be incorporated into portable electronics applications.

[0008] In this application, any description, even if made in relation to a particular embodiment, is applicable to and interchangeable with other embodiments of the present disclosure. Furthermore, when an element or component is said to be included in and / or selected from a list of enumerated elements or components, in the relevant embodiments expressly contemplated herein, the element or component may be any one of the individually enumerated elements or components, or may be selected from a group consisting of any two or more of the explicitly enumerated elements or components; it should be understood that any element or component enumerated in a list of elements or components may be omitted from such list.

[0009] Unless specifically limited otherwise, the terms "alkyl" and derived terms such as "alkoxy", "acyl" and "alkylthio" as used herein include within their scope straight chain, branched chain and cyclic moieties. Examples of alkyl groups are methyl, ethyl, 1-methylethyl, propyl, 1,1-dimethylethyl and cyclopropyl. Unless specifically stated otherwise, each alkyl and aryl group may be unsubstituted or substituted with halogen, hydroxy, sulfo, C1-C6 alkoxy, C1-C6 alkylthio, C1-C6 acyl, formyl, cyano, C6-C6 alkylthio, C1-C6 aryl ... 15 Aryloxy or C6~C 15 It may be substituted with one or more substituents selected from, but not limited to, aryl, provided that the substituents are sterically compatible and chemical bonding and strain energy rules are satisfied. The term "halogen" or "halo" includes fluorine, chlorine, bromine and iodine, with fluorine being preferred.

[0010] The term "aryl" refers to a phenyl, indanyl or naphthyl group. An aryl group may contain one or more alkyl groups, in which case it may be referred to as an "alkylaryl"; for example, it may be composed of an aromatic group and two C1-C6 groups (e.g., methyl or ethyl). An aryl group may also contain one or more heteroatoms, such as N, O or S, in which case it may be referred to as a "heteroaryl" group; these heteroaromatic rings may be fused with other aromatic systems. Such heteroaromatic rings include, but are not limited to, furanyl, thienyl, pyrrolyl, pyrazolyl, imidazolyl, triazolyl, isoxazolyl, oxazolyl, thiazolyl, isothiazolyl, pyridyl, pyridazyl, pyrimidyl, pyrazinyl and triazinyl ring structures. An aryl or heteroaryl substituent may be unsubstituted or may be selected from the group consisting of halogen, hydroxy, C1-C6 alkoxy, sulfo, C1-C6 alkylthio, C1-C6 acyl, formyl, cyano, C6-C6 alkylthio, C1-C6 aryl ... 15 Aryloxy or C6~C 15 It may be substituted with one or more substituents selected from, but not limited to, aryl, provided that the substituents are sterically compatible and chemical bonding and strain energy rules are satisfied.

[0011] As described above, the polymer composition surprisingly had superior dielectric performance and improved mechanical performance relative to the corresponding polymer composition. The weight ratio of the polyolefin was determined according to the following formula: TIFF0007635160000002.tif15170 (in the formula, W PA and W PO are the weights of aliphatic polyamide and functionalized polyolefin, respectively, in the polymer composition. In some embodiments, the polyolefin weight ratio is 60% to 95%, 65% to 95%, 70% to 95%, 55% to 92%, 60% to 92%, 65% to 92%, or 70% to 92%. Of course, in some embodiments, the polymer composition may include multiple distinct polyolefins or distinct aliphatic polyamides, both according to the following description. In some such embodiments, the WPO and W PA are the total weights of the polyolefins and the aliphatic polyamides, respectively, in the polymer composition.

[0012] Regarding the dielectric performance, the dielectric constant (D k ") and dielectric tangent ("D f ") are important in determining the suitability of a material in application settings where wireless communication is present. For example, in portable electronic devices, the dielectric properties of the materials forming the various components and housings can significantly impair wireless radio signals (e.g., frequencies of 1 MHz, 1 GHz, 2.4 GHz, and 5.0 GHz) transmitted and received by the portable electronic device through one or more antennas. The dielectric constant of a material represents, in part, the material's ability to interact with electromagnetic radiation and correspondingly disrupt electromagnetic signals (e.g., radio signals) traveling through that material. Thus, the lower the dielectric constant of a material at a given frequency, the less the material will disrupt electromagnetic signals at that frequency. Similarly, the dielectric loss tangent is proportional to the dielectric loss of a material; the lower the dielectric loss tangent, the lower the dielectric loss of the material.

[0013] The polymer compositions described herein have excellent dielectric performance (relatively low D k and D. f In some embodiments, the polymer composition has a D at 1 MHz of 3.2 or less, 3.1 or less, 3.0 or less, 2.9 or less, 2.8 or less, or 2.7 or less. k Additionally or alternatively, in some embodiments, the polymer composition has a D at 1 MHz of 2.6 or greater. k In some embodiments, the polymer composition has a D at 1 MHz of 2.6 to 3.1, 2.6 to 3.0, 2.6 to 2.9, 2.6 to 2.8, or 2.6 to 2.7. k In some embodiments, the polymer composition has a D at 1 MHz of 0.009 or less, 0.008 or less, 0.007 or less, 0.006 or less, or 0.005 or less. fAdditionally or alternatively, in some embodiments, the polymer composition has a D at 1 MHz of at least 0.0025, or at least 0.003. f In some embodiments, the polymer composition has a D at 1 MHz of 0.0025 to 0.009, 0.0025 to 0.008, 0.0025 to 0.007, 0.0025 to 0.006, 0.0025 to 0.005, 0.003 to 0.009, 0.003 to 0.008, 0.003 to 0.007, 0.003 to 0.006, or 0.003 to 0.005. f D at 1MHz f and D. k can be measured according to ASTM D150 at 1.0 MHz. In some embodiments, the polymer composition has a D in the above range at a frequency of 2.4 GHz. f and D. k D at 2.4 GHz f and D. k can be measured according to ASTM D2520.

[0014] In addition, as discussed above, the polymeric compositions described herein have surprisingly improved mechanical performance (e.g., tensile strength, tensile strain, tensile modulus, and impact strength (notched and unnotched)). More specifically, it has been surprisingly found that polymeric compositions having a polyolefin weight ratio of 55% to 95% have improved mechanical performance relative to corresponding polymeric compositions having a polyolefin weight ratio greater than or less than 55% to 95%. In some embodiments, the polymeric compositions have a tensile strength of at least 80 megapascals ("MPa"), at least 85 MPa, or at least 90 MPa. Additionally or alternatively, in some embodiments, the polymeric compositions have a tensile strength of 100 MPa or less, 95 MPa or less, or 92 MPa or less. In some embodiments, the polymeric compositions have a tensile strength of 80 MPa to 100 MPa, 85 MPa to 100 MPa, 90 MPa to 100 MPa, or 90 MPa to 95 MPa. In some embodiments, the polymeric compositions have a tensile strain of at least 2.8%. Additionally or alternatively, in some embodiments, the polymeric composition has a tensile strain of 3.0% or less. In some embodiments, the polymeric composition has a tensile strain of 2.8% to 3.0%. In some embodiments, the polymeric composition has a tensile modulus of at least 7.8 gigapascals ("GPa"), at least 7.9 GPa, at least 8.0 GPa, or at least 8.1 GPa. Additionally or alternatively, in some embodiments, the polymeric composition has a tensile modulus of 9 GPa or less. In some embodiments, the polymeric composition has a tensile modulus of 7.8 GPa to 9 GPa, 7.9 GPa to 9 GPa, 8.0 GPa to 9 GPa, or 8.1 GPa to 9 GPa. In some embodiments, the polymeric composition has a tensile modulus of at least 11.6 kilojoules per square meter ("kJ / m 2 ") or at least 11.7 kJ / m 2 Additionally or alternatively, in some embodiments, the polymer composition has a notched impact strength of 13 kJ / m 2 In some embodiments, the polymer composition has a notched impact strength of 11.6 kJ / m2 ~13kJ / m 2 or 11.7 kJ / m 2 ~13kJ / m 2 In some embodiments, the polymer composition has a notched impact strength of at least 49 kJ / m 2 Additionally or alternatively, in some embodiments, the polymer composition has an unnotched impact strength of 55 kJ / m 2 In some embodiments, the polymer composition has an unnotched impact strength of 49 kJ / m 2 ~55kJ / m 2 The tensile strength, tensile strain, tensile modulus, notched impact strength and unnotched impact strength can be measured as described in the Examples.

[0015] Functionalized Polyolefin Polymers The polymer composition comprises a functionalized polyolefin polymer. As used herein, a polyolefin polymer is a polymer having at least 50 mol % repeat units R PO In some embodiments, the repeat unit R PO The concentration of repeat unit R is at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or at least 99.9 mol%. As used herein, mol% is relative to the total number of repeat units in the polymer, unless otherwise specified. PO is the following: TIFF0007635160000003.tif38170 (wherein R1 to R4 are independently hydrogen and a group represented by the formula -(CH2) n -CH3, where n is an integer from 0 to 5. For clarity, when n is zero, the alkyl group is a methyl group.

[0016] A functionalized polyolefin polymer is a polyolefin polymer that contains reactive groups that react with amine or carboxylic acid groups on a polyamide polymer to provide a covalent bond (e.g., an amide bond) between the polyolefin polymer and the polyamide polymer in the polymer composition. In other words, a functionalized polyolefin contains at least some repeat units R* according to formula (1): PO wherein at least one of R1 to R4 is replaced with a reactive group; PO Of course, in embodiments where the polyolefin is fully functionalized, the functionalized polyolefin may be a polyolefin having a repeat unit R* PO Contains repeating unit R PO The polyolefin polymers preferably include, but are not limited to, polyethylene, polypropylene, polymethylpentene, polybutene-1, polyisobutylene, ethylene propylene rubber, and ethylene propylene diene monomer rubber; preferably, the polyolefin is polypropylene. The reactive groups preferably include, but are not limited to, maleic anhydride, epoxides, isocyanates, and acrylic acids. Of course, in the polymer composition, the polyolefin is covalently bonded to the polyamide through a residue formed from the reaction of at least a portion of the reactive groups on the polyolefin with an amine or carboxylic acid group on the polyamide. For ease of reference, it will be understood that references to reactive groups on the functionalized polyolefin polymer in the polyamide polymer composition refer to any unreacted reactive groups on the functionalized polyolefin polymer as well as the residue formed from the reaction of the reactive groups with an amine or carboxylic acid on the polyamide. For example, one skilled in the art will understand that a reference to a maleic anhydride functionalized polyolefin in a polyamide polymer composition refers to any unreacted maleic anhydride groups on the polyolefin polymer as well as residues formed from the reaction of maleic anhydride with amine groups of the polyamide polymer.

[0017] In some embodiments, the reactive group is a group of the formula: TIFF0007635160000004.tif92170 (in the formula, R 17 and R 20 is selected from hydrogen and an alkyl group, and R 18 , R 19 , R 21 and R 22 is selected from a bond and an alkyl group. Preferably, R 17 and R 20 are both hydrogen. 18 , R 19 , R 21 and R 22 are all bonds. For clarity, the "*" in formulas (2) to (5) represents the repeating unit R* PO The bond to carbon is shown.

[0018] The polyolefin can be functionalized at its chain ends or along its backbone (or both). In some embodiments where the polyolefin is functionalized along its backbone, the functionalized polyolefin comprises a total of at least 50 mol % of repeat units R PO1 and repeat unit R PO2 (defined below). In some embodiments, the repeating unit R PO1 and R PO2 The total concentration of R is at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, at least 95 mol%, or at least 99 mol%. PO1 and R PO2 In some embodiments, within the total concentration range of the repeat unit R PO2 The concentration of is at least 0.05 mol % to 10 mol %, 0.05 mol % to 8 mol %, 0.05 mol % to 6 mol %, 0.05 mol % to 4 mol %, 0.05 mol % to 2 mol %, 0.05 mol % to 1.5 mol %, or 0.1 mol % to 1.5 mol %.

[0019] Repeating unit R PO1 and R PO2 are the following formulas: TIFF0007635160000005.tif39170 (wherein R5 to R8 are independently hydrogen and a group represented by the formula -(CH2) m -CH3 (wherein m is an integer from 0 to 5); R9 to R 12 are independently hydrogen, a group of formula -(CH2) m’ -CH3 (where m is an integer from 0 to 5) and reactive groups that react with amine or carboxylic acid groups of the polyamide polymer; R9 to R 12 At least one of the groups is a reactive group. In some embodiments, the reactive group is represented by a formula selected from the group consisting of formulas (2)-(5). In some embodiments, R5-R7 are all hydrogen and R8 is -CH3. Additionally or alternatively, in some embodiments, R9 and R 11 are both hydrogen, and R 10 is -CH3, and R 12 is a reactive group as described above, preferably maleic anhydride. Excellent results have been obtained with polypropylene functionalized with maleic anhydride.

[0020] The functionalized polyolefin has repeating units R PO1 and R PO2 In some of the above-described embodiments, including (R PO1 +R PO1 ) for R PO2 The molar ratio (repeating unit R PO1 moles / repeating unit R PO1 +R PO2 The amount of the aryl group (the number of moles) is 0.01 mol % to 6 mol %, 0.01 mol % to 5.6 mol %, or 0.01 mol % to 5 mol %.

[0021] In some embodiments, the functionalized polyolefin polymer has a melt mass flow rate ("MFR") of at least 1 g / 10 min, at least 5 g / 10 min, at least 10 g / 10 min, at least 15 g / 10 min, or at least 20 g / 10 min. Additionally or alternatively, in some embodiments, the functionalized polyolefin polymer has a MFR of 120 g / 10 min or less, 100 g / 10 min or less, 80 g / 10 min or less, or 70 g / 10 min or less. In some embodiments, the functionalized polyolefin polymer has a MFR of 1 g / 10 min to 120 g / 10 min, 5 g / 10 min to 100 g / 10 min, 10 g / 10 min to 80 g / 10 min, or 15 g / 10 min to 70 g / 10 min. The MFR can be measured at 190° C. and 1.2 kg according to ASTM D1238.

[0022] In some embodiments, the functionalized polyolefin concentration in the polymer composition is at least 25 weight percent ("wt %), at least 30 wt %, or at least 35 wt %. Additionally or alternatively, in some embodiments, the functionalized polyolefin concentration in the polymer composition is 55 wt % or less, 52 wt % or less, or 50 wt % or less. In some embodiments, the functionalized polyolefin concentration in the polymer composition is 25 wt % to 55 wt %, 30 wt % to 55 wt %, 35 wt % to 55 wt %, 25 wt % to 52 wt %, 30 wt % to 52 wt %, 35 wt % to 52 wt %, 25 wt % to 50 wt %, 30 wt % to 50 wt %, or 35 wt % to 50 wt %. As used herein, weight percent is a percentage of the total weight of the polymer composition, unless otherwise specified.

[0023] In some embodiments, the polymer composition comprises a plurality of separate functionalized polyolefins according to the above description. In some such embodiments, the total concentration of the separate functionalized polyolefins is within the above range. Those skilled in the art will recognize that the selection of the functionalized polyolefin concentration and the aliphatic polyamide concentration (described below) is related to the weight ratio of the polyolefins. The selection of the functionalized polyolefin concentration and the aliphatic polyamide concentration is made such that the weight ratio of the polyolefins is within the selected range and the total concentration of the functionalized polyolefin, the aliphatic polyamide and the optional additives in the polymer composition is 100 wt% or less.

[0024] Aliphatic Polyamide Polymer As used herein, an aliphatic polyamide polymer is a polymer having at least 50 mole % repeat units R that have amide bonds (-NH-CO-) and no aromatic groups. PA In other words, both the formation of the diamine and the diacid by polycondensation contain repeating R PA In some embodiments, the aliphatic polyamide polymer comprises at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, at least 95 mol%, at least 99 mol%, or at least 99.9 mol% of the repeat unit R PA has.

[0025] In some embodiments, the repeat unit R PA is the following formula: TIFF0007635160000006.tif40170 (in the formula, R 13 ~R 16 is independently selected at each occurrence from the group consisting of hydrogen, alkyl, aryl, alkali or alkaline earth metal sulfonate, alkyl sulfonate, and quaternary ammonium; p is an integer from 4 to 10; and p' is an integer from 7 to 12. In some embodiments, R 13 ~R 16is hydrogen at each position. Additionally or alternatively, in some embodiments, p is 5 or 6 and p' is 8 to 12. In some embodiments, the aliphatic polyamide polymer is selected from the group consisting of PA4,6; PA5,6; PA5,10; PA6,10; PA10,10; and PA10,12.

[0026] In some embodiments, the aliphatic polyamide polymer has an inherent viscosity of 0.7 to 1.4 deciliters / gram ("dL / g") measured according to ASTM D5336.

[0027] In some embodiments, the concentration of the aliphatic polyamide in the polymer composition is at least 3 wt%, at least 4 wt%, or at least 5 wt%. Additionally or alternatively, in some embodiments, the concentration of the aliphatic polyamide in the polymer composition is 45 wt% or less, 30 wt% or less, or 25 wt% or less. In some embodiments, the concentration of the aliphatic polyamide in the polymer composition is 3 wt% to 45 wt%, 4 wt% to 45 wt%, 5 wt% to 45 wt%, 3 wt% to 30 wt%, 4 wt% to 30 wt%, 5 wt% to 30 wt%, 3 wt% to 25 wt%, 4 wt% to 25 wt%, 5 wt% to 25 wt%, or 5 wt% to 20 wt%. In some embodiments, the polymer composition comprises a plurality of distinct aliphatic polyamides according to the above. In some such embodiments, the total concentration of the distinct aliphatic polyamides is within the above range.

[0028] Glass fiber The polyamide polymer composition comprises glass fibers. Glass fibers are silica-based glass compounds containing several metal oxides that can be tailored to give different types of glass. The main oxide is silica in the form of silica sand; other oxides such as calcium, sodium and aluminum are incorporated to lower the melting temperature and prevent crystallization. Glass fibers can be added as endless fibers or chopped glass fibers. Glass fibers generally have an equivalent diameter of 5-20, preferably 5-15 μm, more preferably 5-10 μm. All glass fiber types can be used, such as A, C, D, E, M, S, R, T glass fibers (as described in Additives for Plastics Handbook, 2nd ed, John Murphy, chapter 5.2.3, pages 43-48) or any mixtures thereof or mixtures thereof.

[0029] E, R, S and T glass fibres are well known in the art. They are described, inter alia, in Fiberglass and Glass Technology, Wallenberger, Frederick T.; Bingham, Paul A. (Eds.), 2010, XIV, chapter 5, pages 197-225. R, S and T glass fibres are essentially composed of oxides of silicon, aluminium and magnesium. In particular, they typically contain 62-75% by weight of SiO2, 16-28% by weight of Al2O3 and 5-14% by weight of MgO. On the other hand, R, S and T glass fibres contain less than 10% by weight of CaO.

[0030] In some embodiments, the glass fiber is a high modulus glass fiber. The elastic modulus of the high modulus glass fiber is at least 76, preferably at least 78, more preferably at least 80, and most preferably at least 82 GPa, as measured according to ASTM D2343. Examples of high modulus glass fibers include, but are not limited to, S, R, and T glass fibers. Commercially available sources of high modulus glass fibers are S-1 and S-2 glass fibers provided by Taishan and AGY, respectively.

[0031] In some embodiments, the glass fibers are low D k It is made of glass fiber. Low D k The dielectric constant of the glass fiber is 4.0-5.5, 4.0-5.4, 4.0-5.3, 4.0-5.2, 4.0-5.1 or 4.0-5.0 at frequencies of 1 MHz, 600 MHz, 1 GHz and 2.4 GHz. Low D k Glass fiber has low D f (“Low D k / D f Such glass fibers may have a D of 0.0005 to 0.001 at frequencies of 1 MHz, 1 GHz, 600 MHz, and 2.4 GHz. f Glass fiber D f and D. k can be measured according to ASTM D150 (1.0 MHz) and ASTM D2520 (600 MHz, 1.0 Ghz and 2.4 GHz). In some embodiments, the glass fibers have high modulus and low D k It is glass fiber.

[0032] The morphology of the glass fiber is not particularly limited. As mentioned above, the glass fiber may have a circular cross section ("round glass fiber") or a non-circular cross section ("flat glass fiber"). Non-limiting examples of suitable flat glass fibers include glass fibers having oval, elliptical and rectangular cross sections. In some embodiments in which the polymer composition comprises flat glass fibers, the cross-sectional longest diameter of the flat glass fiber is at least 15 μm, preferably at least 20 μm, more preferably at least 22 μm, and even more preferably at least 25 μm. Additionally or alternatively, in some embodiments, the cross-sectional longest diameter of the flat glass fiber is at most 40 μm, preferably at most 35 μm, more preferably at most 32 μm, and even more preferably at most 30 μm. In some embodiments, the cross-sectional diameter of the flat glass fiber is in the range of 15 to 35 μm, preferably 20 to 30 μm, and more preferably 25 to 29 μm. In some embodiments, the shortest cross-sectional diameter of the flattened glass fibers is at least 4 μm, preferably at least 5 μm, more preferably at least 6 μm, and even more preferably at least 7 μm. Additionally or alternatively, in some embodiments, the shortest cross-sectional diameter of the flattened glass fibers is at most 25 μm, preferably at most 20 μm, more preferably at most 17 μm, and even more preferably at most 15 μm. In some embodiments, the shortest cross-sectional diameter of the flattened glass fibers is in the range of 5 to 20 μm, preferably 5 to 15 μm, and more preferably 7 to 11 μm.

[0033] In some embodiments, the aspect ratio of the flat glass fiber is at least 2, preferably at least 2.2, more preferably at least 2.4, and even more preferably at least 3. The aspect ratio is defined as the ratio of the longest diameter in a cross section of the glass fiber to the shortest diameter in the same cross section. Additionally or alternatively, in some embodiments, the aspect ratio of the flat glass fiber is at most 8, preferably at most 6, and more preferably at most 4. In some embodiments, the aspect ratio of the flat glass fiber is 2 to 6, preferably 2.2 to 4. In some embodiments, where the glass fiber is a round glass fiber, the aspect ratio of the glass fiber is less than 2, preferably less than 1.5, more preferably less than 1.2, even more preferably less than 1.1, and most preferably less than 1.05. Of course, those skilled in the art will understand that, by definition, the aspect ratio cannot be less than 1, regardless of the morphology of the glass fiber (e.g., round or flat).

[0034] In some embodiments, the concentration of glass fibers in the polymer composition is at least 20 wt%, at least 25 wt%, or at least 30 wt%. Additionally or alternatively, in some embodiments, the concentration of glass fibers in the polymer composition is 60 wt% or less, 55 wt% or less, or 50 wt% or less. In some embodiments, the concentration of glass fibers in the polymer composition is 20 wt%-60 wt%, 25 wt%-60 wt%, 30 wt%-60 wt%, 20 wt%-55 wt%, 25 wt%-55 wt%, 30 wt%-55 wt%, 20 wt%-50 wt%, 25 wt%-50 wt%, or 30 wt%-50 wt%.

[0035] Optional Additives In some embodiments, the polyamide polymer composition optionally comprises additives selected from the group consisting of ultraviolet ("UV") stabilizers, heat stabilizers, pigments, dyes, flame retardants, impact modifiers, lubricants, and any combination of one or more of these. In some embodiments where the polymer composition comprises optional additives, the total concentration of the additives is 15 wt% or less, 10 wt% or less, 5 wt% or less, 1 wt% or less, 0.5 wt% or less, 0.4 wt% or less, 0.3 wt% or less, 0.2 wt% or less, or 0.1 wt% or less.

[0036] Formation method The polymer composition can be produced using methods well known in the art. For example, in one embodiment, the polymer composition can be produced by melt blending the polymer, glass fiber, and any optional additives in the blend. Any suitable melt blending method can be used to mix the components of the polymer composition. For example, in one embodiment, all the polymer composition components (e.g., polyamide, polyolefin, glass fiber, and any optional additives) are fed into a melt mixer, such as a single or twin screw extruder, agitator, single or twin screw kneader, or Banbury mixer. The components can be added to the melt mixer all at once, or can be added gradually in several portions. When the components are added gradually in several portions, a portion of the component is added first, and then melt mixed while the remaining components are added successively, until a well-mixed composition is obtained. When the glass fiber exhibits a long physical shape (e.g., long glass fiber), stretch extrusion can be used to produce the reinforced composition.

[0037] Goods Due at least in part to their surprisingly improved dielectric and mechanical performance, the polymer compositions described herein may be desirably incorporated into components of portable electronic devices.

[0038] The term "portable electronic device" is intended to refer to an electronic device designed to be conveniently carried and used in a variety of locations. Representative examples of portable electronic devices may be selected from the group consisting of portable electronic telephones, personal digital assistants, laptop computers, tablet computers, radios, cameras and camera accessories, watches, calculators, music players, global positioning system receivers, portable game consoles, hard drives and other electronic storage devices. Preferred portable electronic devices include laptop computers, tablet computers, portable electronic telephones and watches.

[0039] Without being limited thereto, components of portable electronic devices of interest herein include attachment parts, snap-fit ​​parts, inter-movable parts, functional elements, actuating elements, tracking elements, adjustment elements, carrier elements, frame elements, switches, connectors, cables, housings and any other structural parts other than the housing as used in portable electronic devices, such as speaker parts, etc. Said components of portable electronic devices may be manufactured by injection molding, extrusion molding or other molding techniques, among others.

[0040] A "housing of a portable electronic device" refers to one or more of the back cover, front cover, antenna housing, frame, and / or skeleton of a portable electronic device. The housing may be a single item or may include two or more components. A "skeleton" refers to a structural component to which other components of the device are attached, such as electronics, microprocessor, screen, keyboard and keypad, antenna, battery socket, etc. The skeleton may be an internal component that is not visible or only partially visible from the exterior of the portable electronic device. The housing may provide protection for the internal components of the device from impact and contamination and / or damage by environmental agents (liquids, dust, etc.). Housing components such as covers may also provide substantial or primary structural support and impact protection for certain components exposed to the exterior of the device, such as the screen and / or antenna.

[0041] In a preferred embodiment, the housing of the portable electronic device is selected from the group consisting of a mobile phone housing, an antenna housing, a tablet housing, a laptop computer housing, a tablet computer housing or a watch housing.

[0042] Articles such as portable electronics components can be manufactured from the polymeric compositions using any suitable melt processing method. For example, forming portable electronics components includes injection molding or extrusion of the polymeric compositions. Injection molding is a preferred method. EXAMPLES

[0043] The examples demonstrate the dielectric and mechanical performance of the polymer compositions. The following components were used in the examples: - Polyamide ("PA"): PA6,10 (aliphatic polyamide polymer) available from Radici under the trade name Radipol DC40 - Functionalized Polyolefins ("PO"): ExxonMobil to Exxelor TM A maleic anhydride functionalized polypropylene copolymer commercially available under the trade name PO 1015 - Glass Fiber ("GF"): A low D available from Chongqing Polycomp International Corp under the trade name CS(HL)301HP k / D f Glass fiber. - Additive package: calcium stearate (lubricant) and heat stabilizer, Irganox® 1098 from BASF.

[0044] Sample parameters are shown in Table 1 below. In Table 1, "PO Weight Ratio" refers to the ratio of amounts: TIFF0007635160000007.tif16170 (in the formula, W PO and W PA are the weights of PO and PA in the sample, respectively) Refers to...

[0045] TIFF0007635160000008.tif93170

[0046] In the following examples, f and D. k was measured according to ASTM D150 at 1 MHz. k and D. f Measurements were performed on injection molded disks with dimensions 50.8 mm diameter x 4.0 mm thickness. Tensile modulus, strength and strain were measured on five injection molded ISO tensile bars according to ISO 527-2 using a test speed of 1 mm / min to measure modulus, followed by 5 mm / min to measure tensile strength and strain. Impact strength was measured using a notched Izod impact test according to ISO 180 using ten injection molded ISO bars with dimensions 80 mm length, 4 mm thickness and 10 mm width. Unnotched and notched Izod impact tests were also performed on ISO bars of similar dimensions as notched according to ISO 180.

[0047] Example 1: Performance of polyamide / polypropylene blends This example illustrates the dielectric and mechanical performance of polyamide / polyolefin blends.

[0048] The results of the dielectric performance test are shown in Table 2.

[0049] TIFF0007635160000009.tif131170

[0050] Referring to Table 2, samples with PO weight ratios greater than 50% and less than 100% had improved mechanical performance while maintaining excellent dielectric performance relative to samples with PO weight ratios of 50% and 100%. CE1, E1, E2, and CE2 are in order of increasing PO weight ratio. k and D. fWhile the mechanical properties unexpectedly show a non-linear behavior, with an overall improved mechanical performance observed for samples with 75% and 91% PO weight ratios. For example, tensile strength, tensile strain and tensile modulus all increase from 50% to 75% PO weight ratio. A further increase in the PO weight ratio to 100% then reduces the tensile strength, strain and modulus, in the case of tensile strength and strain, to values ​​lower than those observed for the sample with 50% PO weight ratio (CE1). A similar behavior is observed for the notched and unnotched impact strength, although for such properties a local maximum is observed for a 91% PO weight ratio (E2) and at 100%, the values ​​are below those obtained for the 50% PO weight ratio.

[0051] The above embodiments are intended to be illustrative and not limiting. Further embodiments are within the concept of the present invention. In addition, although the present invention has been described with reference to specific embodiments, those skilled in the art will recognize that changes in form and detail may be made without departing from the spirit and scope of the present invention. Any incorporation by reference of the above documents is limited so that subject matter contrary to the express disclosure herein is not incorporated.

Claims

1. - a functionalized polyolefin; - an aliphatic polyamide, - from 20% to 60% by weight, relative to the total weight of the polymer composition, of glass fibres, having a dielectric constant between 4.0 and 5.5 at a frequency of 1 MHz; a weight ratio of functionalized polyolefin of 55% to 95%; A polymer composition comprising: the functionalized polyolefin weight ratio is determined according to the formula: is given by, and - W ＰＡ and W ＰＯ are the weights of aliphatic polyamide and functionalized polyolefin, respectively, in the polymer composition; - Functionalized polyolefins 、 The following formulas respectively: (In the formula, R ５ ~R ８ are independently hydrogen and a group of the formula -(CH ２ ) ｍ -CH ３ (wherein m is an integer from 0 to 5); R ９ ~R １２ are independently hydrogen, a group of the formula -(CH ２ ) ｍ’ -CH ３ where m is an integer from 0 to 5, and reactive groups which react with amine or carboxylic acid groups of the polyamide polymer; R ９ ~R １２ At least one of the groups is a reactive group. The repeating unit R represented by ＰＯ１ and R ＰＯ２ and The functionalized polyolefin contains from 0.05 mol % to 1.5 mol % of repeating units R ＰＯ２ 1. A polymer composition comprising:

2. 2. The polymer composition of claim 1, wherein the functionalized polyolefin polymer is selected from the group consisting of functionalized polyethylene, functionalized polypropylene, functionalized polymethylpentene, functionalized polybutene-1, functionalized polyisobutylene, functionalized ethylene propylene rubber, and functionalized ethylene propylene diene monomer rubber.

3. The polymer composition of claim 1, wherein the functionalized polyolefin polymer is a functionalized polypropylene.

4. The polymer composition according to any one of claims 1 to 3, wherein the functionalized polyolefin polymer is functionalized with a reactive group selected from the group consisting of maleic anhydride, epoxide, isocyanate and acrylic acid.

5. The polymer composition of claim 4, wherein the reactive group is maleic anhydride.

6. The aliphatic polyamide has the following formula: (In the formula, - R １３ ~R １６ is independently selected at each occurrence from the group consisting of hydrogen, alkyl, aryl, alkali or alkaline earth metal sulfonate, alkyl sulfonate, and quaternary ammonium; p is an integer from 4 to 10; and p' is an integer from 7 to 12. The repeating unit R represented by ＰＡ The polymer composition according to any one of claims 1 to 5, comprising:

7. 5. The polymer composition according to any one of claims 1 to 4, wherein the polyamide is selected from the group consisting of PA4,6; PA5,6; PA5,10; PA6,10; PA10,10; and PA10,12; or the polymer composition according to claim 6, wherein the polyamide is selected from the group consisting of PA5,10; PA6,10; PA10,10; and PA10,12.

8. The polymer composition according to any one of claims 1 to 7, wherein the glass fibre concentration is between 30% and 60% by weight, relative to the total weight of the polymer composition.

9. The polymer composition of claim 1, wherein the glass fiber concentration is from 25% by weight to 50% by weight, based on the total weight of the polymer composition.

10. The polymer composition according to any one of claims 1 to 9, wherein the functionalized polyolefin concentration is from 25% to 55% by weight, relative to the total weight of the polymer composition.

11. The polymer composition of claim 1, wherein the functionalized polyolefin concentration is from 30% to 50% by weight, based on the total weight of the polymer composition.

12. The polymer composition according to any one of claims 1 to 11, wherein the aliphatic polyamide concentration is from 3% to 30% by weight, relative to the total weight of the polymer composition.

13. The polymer composition of claim 1, wherein the aliphatic polyamide concentration is from 5% by weight to 30% by weight, based on the total weight of the polymer composition.

14. A polymer composition according to any one of claims 1 to 13 having a tensile strength of at least 83 MPa.

15. A polymer composition according to any one of claims 1 to 14, having a tensile strain of at least 2.8%.

16. 16. The polymer composition of any one of claims 1 to 15, having a tensile modulus of at least 7.8 GPa.

17. D at 1 MHz of 3.2 or less ｋ and D at 1 MHz of 0.007 or less ｆ The polymer composition according to any one of claims 1 to 16, having the formula:

18. The polymer composition of any one of claims 1 to 16 having a D k at 1 MHz less than or equal to 3.0 and a D f at 1 MHz less than or equal to 0.

007.

19. The polymer composition according to any one of the preceding claims, wherein the polyolefin weight ratio is between 70% and 92% by weight.

20. A component of a portable electronic device comprising the polymer composition according to any one of claims 1 to 19.

21. A component of the portable electronic device described in claim 20, which is a housing for the portable electronic device.

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