WO2020104412A1

WO2020104412A1 - Polyamide/polyolefin blends and corresponding mobile electronic device components

Info

Publication number: WO2020104412A1
Application number: PCT/EP2019/081717
Authority: WO
Inventors: Raleigh L. DAVIS; Vijay Gopalakrishnan; Pascal Lefevre
Original assignee: Solvay Specialty Polymers Usa, Llc
Priority date: 2018-11-20
Filing date: 2019-11-19
Publication date: 2020-05-28

Abstract

Described herein are polyamide polymer compositions including glass fiber and a blend of a polyamide polymer and a functionalized polyolefin polymer ("polyamide/polyolefin blend"), where the polyamide polymer is a semi-aromatic polyamide polymer or an aliphatic polyamide. It was surprisingly discovered that the polyamide polymer compositions including a polyamide/polyolefin blend had increased dielectric performance relative to polyamide polymer compositions free of the functionalized polyolefin polymer ("corresponding polyamide polymer composition"). In some embodiments, it was further surprisingly discovered that the polyamide polymer composition including a polyamide/polyolefin blend also had increased mechanical performance, relative to corresponding polyamide polymer compositions. Due at least in part to the improved dielectric performance, the polyamide polymer compositions can be desirably integrated into mobile electronic device components.

Description

POLYAMIDE/POLYOLEFIN BLENDS AND CORRESPONDING MOBILE ELECTRONIC DEVICE COMPONENTS

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to US provisional patent application no. 62/769627, filed on 20 November 2018 and to European patente application no. 19156910.2, filed on 13 February 2019, the whole content of each of these applications being incorporated herein by reference for all purposes.

FIELD OF THE INVENTION

The invention relates to polymer compositions including a polyamide and a functionalized polyolefin polymer blend have excellent dielectric performance. The invention further relates to mobile electronic device components incorporating the polymer compositions.

BACKGROUND OF THE INVENTION

Due to their reduced weight and high mechanical performance, polyamide compositions are widely used in mobile electronic device components. In particular, polyamide polymer compositions including glass fibers are especially suitable for mobile electronic device applications. Because such compositions can have appropriate mechanical strength, reduced weight and greater design options, they are attractive as a metal replacement in mobile electronic device components.

SUMMARY OF INVENTION

In one aspect, the invention relates to a polyamide polymer composition having 5 wt.% to 35 wt.% of a functionalized polyolefin polymer; 35 wt.% to 65 wt.% of a polyamide selected from a semi-aromatic polyamide polymer and an aliphatic polyamide polymer; and 10 wt.% to 50 wt.% of a glass fiber. In some embodiments, the functionalized polyolefin polymer is selected from the group consisting of a functionalized polyethylene, a functionalized polypropylene, a functionalized polymethylpentene, a functionalized polybutene- 1, a functionalized polyisobutylene, a functionalized ethylene propylene rubber, and a functionalized ethylene propylene diene monomer rubber. Additionally or alternatively, in some embodiments, the functionalized polyolefin polymer is functionalized with a reactive group selected from the group consisting of a maleic anhydride, epoxide, isocyanate, acrylic acid, and silane.

In some embodiments, the semi-aromatic polyamide includes a recurring unit Rp_Ai represented by the following formula:

where R₅ to Rio, at each location, and Rn to R₁₄ are independently selected from the group consisting of a hydrogen, a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium; _¾ and _¾ are independently selected integers from 1 to 5, and _¾ is an integer from 4 to 10. In some embodiments recurring unit R_PAI is represented by the following formula:

Additionally or alternatively, in some embodiments R₅ to Rio, at each location, and Rn to R₁₄ are all hydrogen. In some embodiments, the semi-aromatic polyamide polymer further comprising recurring unit R_PA2 represented by the following formula: In some such embodiments, R₅ to Rio, at each location, and Rn to R₁₄ are all hydrogen. In some embodiments, the polyamide is a semi-aromatic polyamide, and the polymer composition has dielectric constant (“D_k”) at 1 MHz of no more than 3.5 and a dissipation factor (“D_f”) at 1 MHz of no more than 0.008.

In some embodiments, the aliphatic polyamide comprises a recurring unit R_PA2 represented by the following formula:

where R₁₅ to Ris, at each location, is independently selected from the group consisting of a hydrogen, a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium; 11₄ is an integer from 4 to 10; and ns is an integer from 4 to 12. In some embodiments, Ris to Ris, at each location, is a hydrogen.

In some embodiments, the polyamide is an aliphatic polyamide, and the polymer composition includes a dielectric constant (“D_k”) at 2.4 GHz of no more than 3.3, preferably no more than 3.2, more preferably no more than 3.1, still more preferably no more than 3, most preferably no more than 2.95 and a dissipation factor (“D_f”) at 2.4 GHz of no more than 0.009, preferably no more than 0.008. In some embodiments, the polymer composition has a dielectric constant (“D_k”) at 1 MHz of no more than 2.9 and a dissipation factor (“D_f”) at 1 MHz of no more than 0.009. In another aspect, the invention is directed to a mobile electronic device component including the polyamide polymer composition.

DETAILED DESCRIPTION OF THE INVENTION

Described herein are polyamide polymer compositions including glass fiber and a blend of a polyamide polymer and a functionalized polyolefin polymer (“polyamide/polyolefin blend”), where the polyamide polymer is a semi-aromatic polyamide polymer or an aliphatic polyamide. Optionally, the polyamide polymer composition can include additives. It was surprisingly discovered that the polyamide polymer compositions including a polyamide/polyolefin blend had increased dielectric performance relative to polyamide polymer compositions free of the functionalized polyolefin polymer (“corresponding polyamide polymer composition”). In some embodiments, it was further surprisingly discovered that the polyamide polymer composition including a polyamide/polyolefin blend also had increased mechanical performance, relative to corresponding polyamide polymer compositions. Due at least in part to the improved dielectric performance, the polyamide polymer compositions can be desirably integrated into mobile electronic device components. For clarity, a corresponding polyamide polymer composition refers to the polyamide polymer composition including a polyamide/polyolefin blend, where the functionalized polyolefin polymer is replaced by an equivalent amount of the polyamide polymer.

The dielectric constant (“D_k”) and dissipation factor (“D_f”) of a polymer composition is significant in determining the suitability for the material in application settings where radio communication is present. For example, in mobile electronic devices, the dielectric properties of the material forming the various components and housing can significantly degrade wireless radio signals (e.g. 1MHz, 2.4 GHz and 5.0 GHz frequencies) transmitted and received by the mobile electronic device through one or more antennas. The dielectric constant of a material represents, in part, the ability of the material to interact with the electromagnetic radiation and, correspondingly, disrupt electromagnetic signals (e.g. radio signals) travelling through the material. Accordingly, the lower the dielectric constant of a material at a given frequency, the less the material disrupts the electromagnetic signal at that frequency. Similarly, the dissipation factor represents the dielectric losses in a material and, the lower the dissipation factor, the lower the dielectric loss to the material. It was surprisingly discovered that the polyamide polymer compositions including a polyamide/polyolefin blend had increased dielectric performance (lower D_k and D_f), relative to corresponding polyamide polymer compositions. In some embodiments, the polyamide polymer composition has a D at 2.4 GHz of no more than 3.3 or no more than 3.2. Additionally or alternatively, in some embodiments, the polyamide polymer composition has a D_k at 2.4 GHz of no less than 2.8. In some embodiments, the polyamide polymer composition has a D_k at 2.4 GHz from 2.8 to 3.3 or from 2.8 to 3.2. In some embodiments, the polyamide polymer compositions have a D_f at 2.4 GHz of no more than 0.009, or no more than 0.008. Additionally or alternatively, in some embodiments, the polyamide polymer composition has a D_f at 2.4 GHz of no less than 0.006. In some embodiments, the polyamide polymer composition has a D_f at 2.4 MHz from 0.006 to 0.009, or from 0.006 to 0.008. D_f and D_k at 2.4 GHz can be measured according to ASTM D2520.

In some embodiments, the polyamide polymer composition has a D_k at 1 MHz of no more than 3.5, no more than 3.4, or no more than 3.3. Additionally or alternatively, in some embodiments, the polyamide polymer composition has a D_k at 1 MHz of no less than 2.5. In some embodiments, the polyamide polymer composition has a D_k at 1 MHz of from 2.5 to 3.5, from 2.5 to 3.4, or from 2.5 to 3.3. In some embodiments, the polyamide polymer composition has a D_f at 1 MHz of no more than 0.009 or no more than 0.008. Additionally or alternatively, in some embodiments, the polyamide polymer composition has a D_f at 1 MHz of no less than 0.006. In some embodiments, the polyamide polymer composition has a D_f at 1 MHz of rom 0.006 to 0.009 or from 0.006 to 0.008. D_f and D_k at 1 MHz can be measured according to ASTM D 150.

As mentioned above, the polyamide polymer can be a semi-aromatic polyamide polymer or an aliphatic polyamide polymer. In some embodiments in which the polyamide polymer is a semi-aromatic polyamide polymer, the polyamide polymer composition has a D_k at 1 MHz of no more than 3.5, no more than 3.4, or no more than 3.3. Additionally or alternatively, in some embodiments the polyamide polymer is a semi-aromatic polyamide polymer, the polyamide polymer composition has a D_k at 1 MHz of no less than 3.0. In some embodiments in which the polyamide polymer is a semi-aromatic polyamide polymer, the polyamide polymer composition has a D_k at 1 MHz of from 3.0 to 3.5, from 3.0 to 3.4, or from 3.0 to 3.3. In some embodiments in which the polyamide polymer is a semi-aromatic polyamide polymer, the polyamide polymer composition has a D_f at 1 MHz of no more than 0.008, no less than 0.006, or from 0.006 to 0.008.

In some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_k at 2.4 GHz of no more than 3.3, no more than 3.2, no more than 3.1, or no more than 3.0, or no more than 2.95. Additionally or alternatively, in some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D at 2.4 GHz of no less than 2.8. In some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_k at 2.4 GHz of from 2.8 to 3.3, from 2.8 to 3.2, from 2.8 to 3.1, from 2.8 to 3, or from 2.8 to 2.95. In some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_f at 2.4 GHz of no more than 0.009 or no more than 0.008. Additionally or alternatively, in some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_f at 2.4 GHz of no less than 0.006. In some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_f at 2.4 GHz of from 0.006 to 009 or from 0.006 to 0.008. In some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_k at 1 MHz of no more than 2.9, no less than 2.5 or from 2.5 to 2.9. In some embodiments in which the polyamide polymer is an aliphatic polyamide polymer, the polyamide polymer composition has a D_k at 1 MHz of no more than 0.009, no less than 0.006, or from 0.009 to 0.006.

Additionally, as mentioned above, the polyamide polymer compositions have surprisingly improved mechanical properties including, but not limited to, tensile elongation and notched impact resistance. In some embodiments, the polyamide polymer composition has a tensile elongation of at least 2.5%, at least 3.5%, or at least 4%. Additionally or alternatively, in some embodiments the polyamide polymer composition has a tensile elongation of no more than 5.5%. In some embodiments, the polyamide polymer composition has a tensile elongation of from 2.5% to 5.5%, from 3.5% to 5.5% or from 4% to 5.5%. In some embodiments, the polyamide polymer composition has a notched impact resistance of at least 10 kilojoules per square meter (kJ/m²), at least 11 kJ/m², at least 12 kJ/m², or at least 15 kJ/m². Additionally or alternatively, in some embodiments the polyamide polymer composition has a notched impact resistance of no more than 35 kJ/m². In some embodiments, the polyamide polymer composition has a notched impact resistance from 10 kJ/m² to 35 kJ/m², from 11 kJ/m² to 35 kJ/m², from 12 kJ/m² to 35 kJ/m², or from 15 kJ/m² to 35 kJ/m². Tensile elongation can be measured according to ISO 527-2 using 1 mm/minute test speed and injection molded ISO tensile bars. Impact strength can be measured using notched-Izod impact testing according to ISO 180 using injection molded ISO tensile bars.

The Polyamide/Polyolefin Blend

The polyamide polymer composition includes a polyamide/polyolefin blend. In some embodiments, the concentration of the polyamide/polyolefin blend in the polymer composition is at least 50 wt.% or at least 60 wt.%. Additionally or alternatively, in some embodiments the concentration of the polyamide/polyolefin blend in the polymer composition is no more than 90 wt.%, or no more than 80 wt.%. In some embodiments, the concentration of the polyamide/polyolefin blend in the polyamide polymer composition is from 50 wt.% to 90 wt.%, from 60 wt.% to 90 wt.% or from 60 wt.% to 80 wt.%. As used herein, weight percent is relative to the total weight of the polyamide polymer composition, unless explicitly stated otherwise.

In some embodiments, the weight ratio of the polyamide polymer to the functionalized polyolefin polymer (weight polyamide/weight functionalized polyolefin) is at least 1, at least 1.5, at least 2, or at least 2.5. Additionally or alternatively, in some embodiments the weight ratio of the polyamide polymer to the functionalized polyolefin polymer is no more than 6, no more than 5 or no more than 4. In some embodiments, the weight ratio of the polyamide polymer to the functionalized polyolefin polymer is from 1 to 6, from 1 to 5, from 1 to 4, from 1.5 to 4, from 2 to 4, or from 2.5 to 4. The Functionalized Polyolefin Polymer

The polyamide/polyolefin blend includes a functionalized polyolefin polymer. As used herein, a polyolefin polymer refers to any polymer having at least 50 mol% of a recurring unit Rpo. In some embodiments, the concentration of recurring units Rpo 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%. As used herein, mol% is relative to the total number of recurring units the polymer, unless explicitly stated otherwise. Recurring unit R_PO is represented by the following:

> (1A)

where Ri to R₄ are independently selected from the group consisting of a hydrogen and an alkyl group represented by the formula C_nH_2n+i, where n is an integer from 1 to 6.

Functionalized polyolefin polymers are polyolefin polymers that include a reactive group that reacts with an amine group or a carboxylic acid group on the polyamide polymer, resulting in a covalent bond (e.g. an amide bond) between the polyolefin polymer and the polyamide polymer in the polyamide/polyolefin blend. Desirable polyolefin polymers 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. Desirable reactive groups include, but are not limited to, maleic anhydride, epoxide, isocyanate, acrylic acid, and silane. Of course, in the polyamide polymer composition, the polyolefin is covalently bonded to the polyamide through residues formed from the reaction of at least some of the reactive groups on the polyolefin and the amine or carboxylic acid groups on the polyamide. For ease of reference, it will be understood that a reference to the reactive group on the functionalized polyolefin polymer in the polyamide polymer composition refers to any unreacted reactive groups on the polyolefin polymer as well as the residues formed from the reaction the reaction between the reactive group and an amine or carboxylic acid on the polyamide. For example, the person of ordinary skill in the art will understand that reference to maleic anhydride functionalized polyolefin in the polyamide polymer compositions refers to any unreacted maleic anhydride groups on the polyolefin polymer, as well as the residues formed from reaction of the maleic anhydride and the amine groups on the polyamide polymer.

The polyolefin can be functionalized at the polymer chain ends or along the backbone (or both). In some embodiments in which the polyolefin is functionalized along the backbone, the functionalized polyolefin includes, in total, at least 50 mol% of a recurring unit Rpoi and a recurring unit Rpo₂· In some embodiments, the total concentration of recurring units Rpoi and Rpo2 in the functionalized polyolefin polymer 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%.

Recurring units R_POI and R_PO2 are represented by the following formulae, respectively:

where R19 to R22 are independently selected from the group consisting of a hydrogen and an alkyl group represented by the formula C_mH_2m+i, where m is an integer from 1 to 6; R23 to R26 are independently selected from the group consisting of a hydrogen, an alkyl group represented by the formula C_m’H_2m’+i, where m’ is an integer from 1 to 6, and a reactive group that reacts with an amine group or a carboxylic acid group of the polyamide polymer; and at least one ofR₂₃ to R₂6 is a reactive group. In some embodiments, R19 to R_2I are all hydrogen and R₂₂ is a -CH₃. Additionally or alternatively, in some embodiments, R₂₃ and R₂s are both hydrogen, R₂₆ is a -CH₃, and R_¾ is a reactive group as described above. Excellent results were obtained maleic anhydride functionalized polypropylene.

In the above embodiments, in which the functionalized polyamide includes recurring units R_POI and Rpo2, the molar ratio of R_PO2 to

(R_POI + Rpoi)(number of moles of recurring unit R_POi/number of moles of recurring unit R_POi + Rpo2) is from 0.01 mol% to 1 mol%.

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 no more than 120 g/10 min, no more than 100 g/10 min., no more than 80 g/10 min., no more than 70 g/10 min. In some embodiments, the functionalized polyolefin polymer has a MFR of from 1 g/10 min., to 120 g/10 min. from 5 g/10 min to 100 g/10 min, from 10 g/10 min to 80 g/10 min. or from 15 g/10 min to 70 g/10 min. MFR can be measured according to ASTM D1238 at a 190° C and 1.2 kg. In some embodiments, the concentration of the functionalized polyolefin polymer is at least 5 wt%, at least 10 wt.%, or at least 20 wt.%. Additionally or alternatively, in some embodiments, the concentration of the polyolefin polymer is no more than 45 wt.% or no more than 40 wt.%. In some embodiments, the concentration of the polyolefin polymer is from 5 wt.% to 45 wt.%, from 10 wt.% to 45 wt.%, from 10 wt.% to 40 wt.%, or from 20 wt.% to 40 wt.%.

The Polyamide Polymer

The polyamide polymer of the polyamide/polyolefin blend is a semi- aromatic polyamide polymer or an aliphatic polyamide polymer. As used herein, a semi-aromatic polyamide polymer includes at least 50 mol% of a recurring unit Rp_Ai having an amide group (— NH-CO-) and an aryl group. Put another way, recurring units of a polyamide result from the polycondensation of a diamine and a diacid ( e.g . dicarboxylic acid). In a semi-aromatic polyamide, at least one of the diamine and the diacid include an aryl group. In some embodiments, both the diamine and the diacid include an aryl group. In some embodiments, the semi-aromatic polyamide has at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, or at least 95 mol% of recurring unit Rp_Ai .

In some embodiments, recurring unit R_PAI is represented by the following formula:

where R to Rio, at each location, and Rn to R are independently selected from the group consisting of a hydrogen, a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium; _¾ and _¾ are independently selected integers from 1 to 5, and _¾ is an integer from 4 to 10. In some embodiments, R₅ to Rio, at each location, and R₁₁ to Ri₄ are all a hydrogen. Additionally or alternatively, in some embodiments _¾ and _¾ are the same, preferably _¾ and _¾ are both 1. In some embodiments n is 6. As used herein, a dashed bond represents a bond to another atom in polymer and outside the drawn structure, for example, to the atom of another recurring unit R_PAI or to the atom of a different recurring unit.

In some embodiments, RPAI is represented by the following formula:

(3).

In some such embodiments, the semi-aromatic polyamide polymer has an additionally recurring unit R_PA2, represented by the following formula:

In the formula above, in some embodiments, R₅ to Rio, at each location, R₁₁ to Ri₄, and _¾ to n₃ are the same for R_PAI and R_PA2· Put another way, once R₅ to Ri₄ and _¾ to n₃ are selected for one recurring unit R_PAI or RPA2, the same selections are present for R_PA2 or RPAI , respectively. In some embodiments including both R_PAI and R PAI , the mole ratio of RPAI to RPA2 (number of moles R_PAI : number of moles R_PA2 in the semi-aromatic polyamide polymer) is 90:10 to 60:40 or 80:20 to 70:30. Excellent results were obtained when the semi-aromatic polyamide was MXD6 or a MXD6/PXD6 copolymer. In some embodiments, the semi-aromatic polyamide polymer has an inherent viscosity of 0.7 to 1.4 deciliters/g (“dL/g”), as measured according to ASTM D5336.

In some embodiments, the polyamide polymer is an aliphatic polymer. As used herein, an aliphatic polyamide polymer includes at least 50 mol% of a recurring unit R_PA3 which has an amide bond and is free of any aromatic groups. Put another way, both the diamine and diacid forming recurring R_PA3 are free of any aromatic groups. In some embodiments, the aliphatic polyamide polymer has at least 60 mol%, at least 70 mol%, at least 80 mol%, at least 90 mol%, at least 95 mol%, or at least 95 mol% of recurring unit R_PA3·

In some embodiments, recurring unit R_PA3 is represented by the following formula:

where R ₁₅ to R_{| ¾}, at each location, is independently selected from the group consisting of a hydrogen, a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium; 11₄ is an integer from 4 to 10; and and ns is an integer from 4 to 12. In some embodiments, R₁₅ to R_{| ¾}, at each location, is a hydrogen. Additionally or alternatively, in some embodiments, 11₄ is 5 or 6 and ns is 8 to 12. In some embodiments, the aliphatic polyamide polymer is selected from the group consisting of PA4,6; PA5,6; PA6,6; PA5,10; PA6,10; PA10,10; and PA10,12.

In some embodiments, the aliphatic polyamide polymer has an inherent viscosity of 0.7 to 1.4 deciliters/g (“dL/g”), as measured according to ASTM D5336.

In some embodiments, the concentration of the polyamide polymer is at least 30 wt.%, or at least 40 wt.%. Additionally or alternatively, in some embodiments, the concentration of the polyamide polymer is no more than 60 wt.%. In some embodiments, the concentration of the polyamide polymer is from 30 wt.% to 60 wt.% or from 40 wt.% to 60 wt.%. The Glass Fiber

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

E, R, S and T glass fibers are well known in the art. They are notably described in Fiberglass and Glass Technology, Wallenberger, Frederick T.; Bingham, Paul A. (Eds.), 2010, XIV, chapter 5, pages 197-225. R, S and T glass fibers are composed essentially of oxides of silicon, aluminium and magnesium. In particular, those glass fibers comprise typically from 62-75 wt. % of Si02, from 16-28 wt. % of A1203 and from 5-14 wt. % of MgO. On the other hand, R, S and T glass fibers comprise less than 10 wt. % of CaO.

In some embodiments, the glass fiber is a high modulus glass fiber. High modulus glass fibers have an elastic modulus of 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. A commercially available source of high modulus glass fibers is S-l and S-2 glass fibers from Taishan and AGY, respectively.

In some embodiments, the glass fiber is a low D_k glass fiber. Low Dk glass fibers have a dielectric constant of 5.1 to 5.5, or from 5.2 to 5.4, at frequencies from 1 MHz to 10 GHz, or at a frequency of 1 MHz, 2.4 MHz or 5 GHz. The dielectric constant of the glass fibers can be measured according to ASTM D150 (1.0 MHz) and ASTM D2520 (2.4 GHz). In some embodiments, the glass fiber is a high modulus and low D glass fiber.

The morphology of the glass fiber is not particularly limited. As noted above, the glass fiber can it can have a circular cross-section (“round glass fiber”) or a non-circular cross-section (“flat glass fiber”). Examples of suitable flat glass fibers include, but are not limited to, glass fibers having oval, elliptical and rectangular cross sections. In some embodiments in which the polymer composition includes a flat glass fiber, the flat glass fiber has a cross-sectional longest diameter of at least 15 pm, preferably at least 20 pm, more preferably at least 22 pm, still more preferably at least 25 pm. Additionally or alternatively, in some embodiments, the flat glass fiber has a cross-sectional longest diameter of at most 40 pm, preferably at most 35 pm, more preferably at most 32 pm, still more preferably at most 30 pm. In some embodiments, the flat glass fiber has a cross-sectional diameter was in the range of 15 to 35 pm, preferably of 20 to 30 pm and more preferably of 25 to 29 pm. In some embodiments, the flat glass fiber has a cross-sectional shortest diameter of at least 4 pm, preferably at least 5 pm, more preferably at least 6 pm, still more preferably at least 7 pm. Additionally or alternatively, in some embodiments, the flat glass fiber has a cross-sectional shortest diameter of at most 25 pm, preferably at most 20 pm, more preferably at most 17 pm, still more preferably at most 15 pm. In some embodiments, the flat glass fiber has a cross-sectional shortest diameter was in the range of 5 to 20 preferably of 5 to 15 pm and more preferably of 7 to 11 pm.

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

In some embodiments, the concentration of the glass fiber is at least

10 wt.%, at least 20 wt.%, at least 25 wt.% or at least 30 wt.%. Additional or alternatively, in some embodiments, the concentration of the glass fiber is no more than 50 wt.%. In some embodiments, the concentration of the glass fiber is from 10 wt.% to 50 wt.%, from 20 wt.% to 50 wt.%, from 25 wt.% to 60 wt.% or from 30 wt.% to 60 wt.%. Optional Additives

In some embodiments, polyamide polymer composition optionally includes an additive selected from the group consisting of ultra-violet (“UV”) stabilizers, heat stabilizers, pigments, dyes, flame retardants, impact modifiers, and any combination of one or more thereof. When present the total concentration of additives is at least 0.5 wt.% or at least 1 wt.%. Additionally or alternatively, in some embodiments, the total concentration of the additives is no more than 20 wt.%, no more than 15 wt.%, no more than 10 wt.%, no more than 5 wt.%, no more 4 wt.% or no more than 3 wt.%. In some embodiments, the total concentration of the additives is from 0.5 wt.% to 20 wt.%, from 0.5 wt.% to 15 wt.%, from 0.5 wt.% to 10 wt.%, from 0.5 wt.% to 5 wt.%, from 1 wt.% to 5 wt.%, from 1 wt.% to 4 wt.% or from 1 wt.% to 3 wt.%.

Formation Methods

The polyamide polymer blends can be made using methods well known in the art. For example, in one embodiment, the polyamide polymer composition can be made by melt-blending the polymers in the blend, the glass fibers, and any optional additives. Any suitable melt-blending method may be used for combining the components of the polymer composition. For example, in one embodiment, all of the polyamide polymer composition components ( e.g . the polyamide, the polyolefin, the glass fiber and any optional additives) are fed into a melt mixer, such as single screw extruder or twin screw extruder, agitator, single screw or twin screw kneader, or Banbury mixer. The components can be added to the melt mixer all at once or gradually in batches. When the components are gradually added in batches, a part of the components is first added, and then is melt-mixed with the remaining components are subsequently added, until an adequately mixed composition is obtained. If a glass fiber presents a long physical shape (for example, a long glass fiber), drawing extrusion molding may be used to prepare a reinforced composition.

‘Articles

Due at least in part to its surprisingly improved dielectric performance and mechanical performance, the polymer compositions described here can be desirably integrated into mobile electronic device components.

The term“mobile electronic device” is intended to denote an electronic device that is designed to be conveniently transported and used in various locations. Representative examples of mobile electronic devices may be selected from the group consisting of mobile electronic phones, personal digital assistants, laptop computers, tablet computers, radios, cameras and camera accessories, watches, calculators, music players, global positioning system receivers, portable games, hard drives and other electronic storage devices. Preferred mobile electronic devices include laptop computers, tablet computers, mobile electronic phones and watches.

Components of mobile electronic devices of interest herein include, but are not limited to, fitting parts, snap fit parts, mutually moveable parts, functional elements, operating elements, tracking elements, adjustment elements, carrier elements, frame elements, switches, connectors, cables, housings, and any other structural part other than housings as used in a mobile electronic devices, such as for example speaker parts. Said mobile electronic device components can be notably produced by injection molding, extrusion or other shaping technologies.

A“mobile electronic device housing” refers to one or more of the back cover, front cover, antenna housing, frame and/or backbone of a mobile electronic device. The housing may be a single article or comprise two or more components. A“backbone” refers to a structural component onto which other components of the device, such as electronics, microprocessors, screens, keyboards and keypads, antennas, battery sockets, and the like are mounted. The backbone may be an interior component that is not visible or only partially visible from the exterior of the mobile electronic device. The housing may provide protection for internal components of the device from impact and contamination and/or damage from environmental agents (such as liquids, dust, and the like). Housing components such as covers may also provide substantial or primary structural support for and protection against impact of certain components having exposure to the exterior of the device such as screens and/or antennas.

In a preferred embodiment, the mobile electronic device housing 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.

The article such as the mobile electronic device components can be made from the polymer composition using any suitable melt-processing method. For example, formation of the mobile electronic device component includes injection molding or extrusion molding the polymer composition. Injection molding is a preferred method.

EXAMPLES

The examples demonstrate the dielectric performance and mechanical performance of the polyamide polymer compositions. In the examples, the following components were used:

Polyamides

- PA6,10 (aliphatic polyamide polymer), commercially obtained under the trade name Radipol DC40 from Radici

- MXD6 (semi-aromatic polyamide polymer 1) from Solvay Specialty Polymers, trade name MXD6 PArA 000

- MXD6/PXD6 (semi-aromatic polyamide polymer 2) from Mitsubishi Gas Chemical, trade name Nylon MP6.

Functionalized Polyolefin

- maleic anhydride functionalized polypropylene copolymer, commercially obtained under the trade name Exxelor™ PO 1015, from ExxonMobil

Glass Fiber

- Low D_k glass fiber from CPIC, trade name CS(HL)301HP (“GF 1”)

- S-l Glass fiber from Taishan, trade name SI HM435TM (“GF 2”)

In the examples below, the dielectric constant and dissipation factor were measured according to ASTM D150 (1 MHz) and ASTM 2520 (2.4 GHz). Measurements of D and D_f at 1 MHz were taken on injection molded discs having dimensions of 2 inches diameter by 1/8 inch thickness. Measurements of D_k and D_f at 2.4 GHz were taken on machined samples of injection molded discs having dimensions of 2 inches diameter by 1/8 inch thickness. Tensile modulus, strength, and elongation were measured according to ISO 527-2 using 1 mm/minute test speed and injection molded ISO tensile bars. Impact strength was measured using notched-Izod impact testing according to ISO 180 using 5 injection molded ISO tensile bars.

Example 1 : Polyamide Polymer Compositions with Polyamide/Polyolefin Polymer Blends Including an Aliphatic Polyamide Polymer

The present example demonstrates the dielectric and mechanical performance of polyamide polymer composition including a polyamide/polyolefin blend including an aliphatic polyamide polymer. To demonstrate performance, 5 samples were formed and dielectric performance and mechanical performance was tested. Sample parameters and testing results are displayed in Table 1.

TABLE 1

Referring to Table 1, the polyamide polymer compositions including a polyamide/polyolefin blend had significantly improved dielectric performance and tensile elongation, relative to the corresponding polyamide polymer composition. For example, El and E2 had significantly improved D_k and D_f at 2.4 GHz, relative to CE1. El and E2 also had improved tensile elongation relative to CE1. While E2 had lower notched- impact performance relative to CE1, the balance of properties (dielectric performance and tensile elongation) of E2 is improved relative to CE1. Polyamide Polymer Compositions with Polyamide/Polyolefin Polymer Blends

Including a Semi- Aromatic Polyamide Polymer

The present example demonstrates the dielectric and mechanical performance of polyamide polymer composition including a polyamide/polyolefin blend including a semi-aromatic polyamide polymer.

To demonstrate performance, 5 samples were formed and dielectric performance and mechanical performance was tested. Sample parameters and testing results are displayed in Table 2.

TABLE 2

Referring to Table 2, the polyamide polymer compositions including a polyamide/polyolefin blend had significantly improved dielectric performance and mechanical performance, relative to the corresponding polyamide polymer composition. For example, E5 and E6 had significantly improved D_k and D_f at 1 GHz, as well as significantly improved tensile elongation and notched impact resistance, relative to CE2. Similar results are seen with comparison of E7 with CE3. El and E2 also had improved tensile elongation relative to CE1. While E2 had lower notched- impact performance relative to CE1, the balance of properties (dielectric performance and tensile elongation) of E2 is improved relative to CE1.

The embodiments above are intended to be illustrative and not limiting.

Additional embodiments are within the inventive concepts. In addition, although the present invention is described with reference to particular embodiments, those skilled in the art will recognized that changes can be made in form and detail without departing from the spirit and scope of the invention. Any incorporation by reference of documents above is limited such that no subject matter is incorporated that is contrary to the explicit disclosure herein.

Claims

1. A polyamide polymer composition comprising:

- 5 wt.% to 35 wt.% of a functionalized polyolefin polymer,

- 35 wt.% to 65 wt.% of a polyamide selected from a semi-aromatic polyamide polymer and an aliphatic polyamide polymer; and

- 10 wt.% to 50 wt.% of a glass fiber comprising a dielectric constant of 5.1 to 5.5 at 1 MHz, as measured according to ASTM D150.

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

3. The polymer composition of either claim 1 or 2, wherein the functionalized polyolefin polymer is functionalized with a reactive group selected from the group consisting of a maleic anhydride, epoxide, isocyanate, acrylic acid, and silane.

4. The polymer composition of any one of claims 1 to 3, wherein the semi-aromatic polyamide comprises a recurring unit R_PAI represented by the following formula:

wherein - R₅ to Rio, at each location, and Rn to R₁₄ are independently selected from the group consisting of a hydrogen, a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium,

- ni and n₂ are independently selected integers from 1 to 5, and

- _¾ is an integer from 4 to 10.

5. The polymer composition of claim 4, wherein recurring unit R_PAI is represented by the following formula:

6. The polymer composition of claim 5, wherein R₅ to Rio, at each location, and Rn to R₁₄ are all hydrogen.

7. The polymer composition of either claim 5 or 6, wherein the semi- aromatic polyamide polymer further comprising a recurring unit R_PA2 represented by the following formula:

8. The polymer composition of claim 7, wherein R₅ to Rio, at each location, and Rn to R₁₄ are all hydrogen.

9. The polymer composition of any one of claims 1 to 8, wherein - the polyamide is a semi-aromatic polyamide, and

- the polymer composition comprises

- a dielectric constant (“D_k”) at 1 MHz of no more than 3.5 and

- a dissipation factor (“D_f”) at 1 MHz of no more than 0.008.

10. The polymer composition of any one of claims 1 to 8, wherein the aliphatic polyamide comprises a recurring unit R_PA2 represented by the following formula:

wherein

- Ri₅ to Rig, at each location, is independently selected from the group consisting of a hydrogen, a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, and a quaternary ammonium,

- 114 is an integer from 4 to 10; and

- _¾ is an integer from 4 to 12.

11. The polymer composition of claim 10, wherein R 5 to Ris, at each location, is a hydrogen.

12. The polymer composition of claims 10 or 11, wherein the polyamide is an aliphatic polyamide, and

- the polymer composition comprises

- a dielectric constant (“D_k”) at 2.4 GHz of no more than 3.3, preferably no more than 3.2, more preferably no more than 3.1, still more preferably no more than 3, most preferably no more than 2.95 and

- a dissipation factor (“D_f”) at 2.4 GHz of no more than 0.009, preferably no more than 0.008.

13. The polymer composition of any one of claims 11 to 12, wherein the polymer composition comprises: a dielectric constant (“D_k”) at 1 MHz of no more than 2.9 and

- a dissipation factor (“D_f”) at 1 MHz of no more than 0.009.

14. A mobile electronic device component comprising the polymer composition of any one of claims 1 to 13.

15. The mobile electronic device component of claim 14, wherein the mobile electronic device is a mobile electronic device housing.