Liquid crystal polyester (LCP) and thermoplastic compositions with low dielectric constant (Dk) and dissipation factor (Df)

Abstract

The present invention relates to liquid crystal polyesters (LCPs) and thermoplastic compositions comprising such LCPs that exhibit low dielectric constants and dissipation factors and are suitable for portable electronic device components, such as films or structural parts.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 120436, filed December 2, 2020, and European Patent Application No. 21157098.1, filed February 15, 2021, the entire contents of which are incorporated herein by reference for all purposes.

[0002] The present disclosure relates to liquid crystalline polyesters (LCPs) and thermoplastic compositions comprising such LCPs that exhibit low dielectric constants and dissipation factors and are suitable for portable electronic device components, such as films or structural parts. [Background technology]

[0003] Due to their reduced weight and high mechanical performance, polymer compositions are widely used to manufacture portable electronic device components. Currently, there is a high market demand for polymer compositions used to manufacture portable electronic device components with improved dielectric performance (i.e., low dielectric constant and dissipation factor).

[0004] In portable electronic devices, the materials forming the various components and housings can significantly degrade radio signals (e.g., frequencies of 1 MHz, 2.4 GHz, 5.0 GHz, 20.0 GHz) transmitted and received by the portable electronic device through one or more antennas. The dielectric performance of materials used in portable electronic devices can be determined by measuring the dielectric constant, since the dielectric constant represents the ability of a material to interact with electromagnetic radiation and disrupt electromagnetic signals (e.g., radio signals) traveling through the 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.

[0005] Applicants have identified a new class of liquid crystalline polyesters (LCPs) with improved dielectric performance that makes them suitable, among other things, as materials for portable electronic device components.

[0006] These LCPs are derived from specific combinations of components / monomers such as aromatic monomers as well as cyclohexanedicarboxylic acid monomers.

[0007] U.S. Patent Application Publication No. 2020 / 017769 (Kuraray Co., Ltd.) relates to a thermoplastic LCP that can reduce the dielectric loss tangent in the high frequency band and have a controlled increase in melting point. However, the LCP described in this publication does not contain any cyclohexanedicarboxylic acid monomers, such as CHDA.

[0008] US Patent No. 6,093,787 (Eastman Chemical Company) relates to LCPs containing cyclohexanedicarboxylic acid (CHDA) moieties and to molding compositions comprising such LCPs and glass fibers.

[0009] U.S. Patent Application Publication No. 2020 / 0102420 (SK Chemicals) discloses an LCP containing an alicyclic dicarboxylic acid or its derivative. The alicyclic dicarboxylic acid or its derivative is introduced into a liquid crystal polymer to improve the insulating properties of the polymer. The alicyclic dicarboxylic acid or its derivative includes a cycloalkanedicarboxylic acid having 5 to 20 carbon atoms or an ester compound thereof. Preferably, 1,4-cyclohexanedicarboxylic acid (CHDA) can be used. The LCPs described in these publications have a large amount of repeating units derived from hydroquinone and 4-hydroxybenzoic acid. However, they do not have the expected dielectric performance compared to the compositions of the present invention.

[0010] U.S. Pat. No. 4,355,133 (Celanese Corp) and U.S. Pat. No. 4,318,842 (Celanese Corp) both disclose the following repeating unit: [ka] The document describes melt-processable polyesters that can form an anisotropic melt phase at temperatures below approximately 350°C, consisting essentially of: (I) (II) (III ...

[0011] U.S. Patent No. 5,747,175 (Hoechst) describes LCP blends with reproducible color properties, stable temperature, and high chemical resistance for use in automotive finishes. This document generally describes the use of aromatic components to prepare the LCP, but also states that aliphatic and alicyclic components, such as cyclohexanedicarboxylic acid, can be used. The only example in this document describes the use of CHDA at a molar content totaling 10 mole percent.

[0012] However, none of the above-listed publications describe the LCPs of the present invention and their advantageous properties as components of portable electronic devices. Summary of the Invention

[0013] One aspect of the present disclosure is directed to liquid crystal polyesters (LCPs) comprising specific combinations of repeat units. Applicants have discovered that the combination of certain repeat units in specific molar amounts leads to the preparation of LCP resins with improved dielectric performance and a range of thermal transition temperatures that make them most useful as materials for films and portable electronic device articles or components.

[0014] Other aspects of the present invention are directed to thermoplastic compositions (C) comprising such LCPs, methods for preparing such LCPs and compositions, and the use of such polymer products to prepare articles or components used in portable electronic devices or transportation, such as automobiles. DETAILED DESCRIPTION OF THE INVENTION

[0015] Disclosed herein are liquid crystal polyesters (LCPs) and thermoplastic compositions (C) comprising such LCPs, which have improved dielectric properties, making them particularly suitable as materials for films and portable electronic device articles or components. The LCPs of the present invention are also suitable for transportation (e.g., automobiles, aeronautics, drones).

[0016] More specifically, the LCPs of the present invention are prepared from specific molar amounts of cyclohexanedicarboxylic acid in combination with a selection of aromatic components, and this specific combination of components has been shown to provide improved dielectric performance to the LCPs or compositions comprising such LCPs, as compared to, for example, LCPs containing higher amounts of cyclohexanedicarboxylic acid components.

[0017] The introduction of selected molar ratios of cyclohexanedicarboxylic acid (CHDA) has also been shown to allow control of the melting temperature (Tm) and crystallization temperature (Tc) of LCPs while maintaining liquid crystalline properties, which is desirable for various processing requirements.

[0018] More specifically, the LCP of the present invention has, based on the total number of moles in the LCP: 40 to 98 mol % of formula (I): [ka] Repeating units of - 1 to 20 mol % of compounds of formula (IIa), (IIb), (IIc) and / or (IId): [ka] Repeating units of - 1 to 12 mol % of compounds of formula (IIIa) and / or (IIIb): [ka] Repeating units of Includes.

[0019] The LCPs described herein can be LCPs consisting essentially of the repeating units described above, or LCPs that include such repeating units, optionally including additional repeating units as described below.

[0020] In some embodiments, when the LCP of the present invention includes additional repeat units, these repeat units are [ka] It may be selected from the group consisting of:

[0021] Each of these repeating units (IV), (V) and / or (VI) may be present in the LCP in a molar amount ranging from 0.1 to 15 mol %, for example, 0.5 to 13 mol %, 1 to 11 mol %, 2 to 9 mol %, or 3 to 8 mol %, based on the total number of moles in the LCP.

[0022] In some other embodiments, when the LCP of the present invention includes an additional repeat unit, the additional repeat unit is [ka] It may be selected from the group consisting of:

[0023] Each of these repeating units (VII), (VIII), (IX), (X), (XI) and / or (XI) may be present in the LCP in a molar amount ranging from 0.1 to 15 mol %, for example, 0.5 to 13 mol %, 1 to 11 mol %, 2 to 9 mol %, or 3 to 8 mol %, based on the total number of moles in the LCP.

[0024] According to the present invention, when the LCP of the present invention includes additional repeat units, these additional repeat units can be selected from the group consisting of (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI), and (XI). The LCP can include one, two, three, four, five, six, seven, eight, or nine of these repeat units. Each of these repeat units can be present in the LCP in a molar amount ranging from 0.1 to 15 mol %, for example, 0.5 to 13 mol %, 1 to 11 mol %, 2 to 9 mol %, or 3 to 8 mol %, based on the total number of moles in the LCP.

[0025] In this application: - all statements, even if made in relation to a particular embodiment, are applicable to and interchangeable with other embodiments of the present disclosure; - When an element or component is said to be included in and / or selected from a list of enumerated elements or components, in relevant embodiments expressly contemplated in this application, the element or component can also be any one of the individually enumerated elements or components, or can be selected from a group consisting of any two or more of the explicitly enumerated elements or components; it is to be understood that any element or component enumerated in a list of elements or components can be omitted from such list; - Any recitation herein of numerical ranges by endpoints includes all numbers subsumed within the recited range, as well as the endpoints of the range, and equivalents thereof.

[0026] In this application, the terms "comprising" or "comprise" include "consisting essentially of" (or "consist essentially of") and also "consisting of" (or "consist of").

[0027] Use of the singular forms "a" or "one" herein includes the plural unless specifically stated otherwise.

[0028] Throughout this document, all temperatures are given in degrees Celsius (°C).

[0029] The LCP of the present invention comprises repeating units (I), (II), and (III). As described throughout this application, the repeating unit (II) can conform to formula (IIa), (IIb), (IIc), and / or (IId). This means, for example, that the LCP of the present invention can comprise several distinct repeating units (II), such as (IIa) and (IId) or (IIa), (IIb), and (IIc). Preferably, the LCP of the present invention comprises repeating units (IIa) and / or (IId). The same is true for repeating units (III), which can conform to formula (IIIa) and / or (IIIb). Preferably, the LCP of the present invention comprises repeating unit (IIIa).

[0030] More specifically, the LCP of the present invention contains 40 to 98 mol % of repeating units of formula (I), preferably 40 to 90 mol %, more preferably 50 to 85 mol % or 60 to 81 mol %, of repeating units of formula (I), based on the total number of moles in the LCP. The LCP of the present invention further contains 1 to 22 mol % of repeating units of formula (IIa), (IIb), (IIc) and / or (IId), preferably 5 to 21 mol % or 10 to 20 mol %, of repeating units of formula (IIa), (IIb), (IIc) and / or (IId), based on the total number of moles in the LCP. The LCP of the present invention also contains 1 to 12 mol % of repeat units of formula (IIIa) and / or (IIIb), preferably 2 to 12 mol %, or 2 to 11 mol %, or 3 to 11 mol %, or 3 to 10 mol %, or 4 to 9.5 mol %, or 4.5 to 8.5 mol % of repeat units of formula (IIIa) and / or (IIIb), based on the total number of moles in the LCP. In these embodiments, the LCP may be made from the following monomers: 6-hydroxy-2-naphthoic acid (HNA) (or a derivative such as 6-acetoxy-2-naphthoic acid (AcHNA)), biphenol (BP) (or a derivative such as diacetoxybiphenyl (AcBP)), hydroquinone (HQ) (or a derivative such as diacetoxybenzene (AcHQ)), and cyclohexanedicarboxylic acid (CHDA). CHDA monomers are generally cis / trans isomer blends, where the cis / trans ratio can vary between 1:99 and 99:1, e.g., between 10:90 and 90:10. For example, LCPs can be prepared from hydroxy-2-naphthoic acid (HNA) (or a derivative), biphenol (BP) (or a derivative) and / or hydroquinone (HQ) (or a derivative), and cyclohexanedicarboxylic acid (CHDA). For example, LCPs can be prepared exclusively from three or four of these monomers. Various isomers of biphenol (BP) can be used to prepare the LCPs of the present invention. Biphenol (BP) can be, for example, in the form of 4,4'-biphenol (4,4'-BP), 3,4'-biphenol (3,4'-BP), or 3,3'-biphenol (3,3'-BP). One or several of these isomers can be used.Preferably, at least 4,4'-biphenol is used to prepare the LCP of the present invention.Various isomers of hydroquinone (HQ) can also be used in the context of the present invention.

[0031] The LCP of the present invention may further comprise repeating units (IV), (V), and / or (VI). In these embodiments, the LCP may be made from the following monomers: 2,6-naphthalenedicarboxylic acid (NDA) (or a derivative) and bibenzoic acid (BB) (or a derivative). Various isomers of bibenzoic acid (BB) may be used to prepare the LCP of the present invention. Bibenzoic acid (BB) may be in the form of 4,4'-bibenzoic acid (4,4'-BB) and / or 3,4'-bibenzoic acid (3,4'-BB).

[0032] In some embodiments, the LCP of the present invention comprises: - 65 to 75 mol % of repeating units of formula (I), - 13 to 18 mol % of repeating units of the formulae (IIa), (IIb), (IIc) and / or (IId), and - 3 to 9 mol % of repeating units of formula (IIIa) and / or (IIIb), Optionally, the following repeating units: - 3 to 11 mol % of repeating units of formula (IV), - 3 to 11 mol % of repeating units of formula (V), and / or - 3 to 11 mol % of repeating units of formula (VI) At least one of Includes.

[0033] In some preferred embodiments, the LCP of the present invention comprises: - 65 to 75 mol % of repeating units of formula (I), - 13 to 18 mol % of repeating units of the formulae (IIa), (IIb), (IIc) and / or (IId), - 3 to 9 mol % of repeating units of formula (IIIa) and / or (IIIb), and - optionally 3 to 11 mol % of repeat units of formula (IV) comprising or consisting essentially of

[0034] The LCPs of the present invention may further comprise repeat units (VII), (VIII), (IX), (X), (XI), and / or (XII). In these embodiments, the LCPs may be made from the following monomers: hydroxybenzoic acid (HBA) (or a derivative, such as acetoxybenzoic acid (AcHBA)), terephthalic acid (TPA) (or a derivative), isophthalic acid (IPA) (or a derivative), resorcinol (RS) (or a derivative), and / or catechol (CT) (or a derivative). In these embodiments, the LCP can be made from the following monomers: 6-hydroxy-2-naphthoic acid (HNA) (or a derivative, such as 6-acetoxy-2-naphthoic acid (AcHNA)), biphenol (BP) (or a derivative, such as diacetoxybiphenyl (AcBP)), hydroquinone (HQ) (or a derivative, such as diacetoxybenzene (AcHQ)), cyclohexanedicarboxylic acid (CHDA), terephthalic acid (TPA) (or a derivative), and / or isophthalic acid (IPA) (or a derivative). For example, the LCP can be made exclusively from HNA (or a derivative), BP or (a derivative), HQ (or a derivative), CHDA (or a derivative), and TPA (or a derivative). The LCP can also be made exclusively from HNA (or a derivative), BP (or a derivative), HQ (or a derivative), CHDA (or a derivative), and IPA (or a derivative). LCP can also be made exclusively from HNA (or a derivative), BP (or a derivative), HQ (or a derivative), CHDA (or a derivative), TPA (or a derivative), and IPA (or a derivative).

[0035] Various isomers of hydroxybenzoic acid (HBA) can be used to prepare the LCP of the present invention. In particular, HBA can be in the form of 4-hydroxybenzoic acid (4-HBA) and / or 3-hydroxybenzoic acid (3-HBA).

[0036] In some embodiments, the LCP of the present invention is such that the number of moles of repeat units is as follows: - formula (I)+(II)+(III)+(IV)+(V)+(VI)+(VII)+(VIII)+(IX)+(X)+(XI)+(XII)=100 mol %, in which the number of moles of repeating units of formula (IV), (V), (VI), (VII), (VIII), (IX), (X), (XI) and / or (XII) is ≥ 0 mol %; - formula (I)+(II)+(III)+(IV)+(V)+(VI)=100 mol %, where the number of moles of repeating units of formula (IV), (V) and / or (VI) is ≥ 0 mol %, and - Formula (I)+(II)+(III)+(VII)+(VIII)+(IX)+(X)+(XI)+(XII)=100 mol %, wherein the number of moles of repeating units of formulae (VII), (VIII), (IX), (X), (XI) and / or (XII) is ≥ 0 mol %.

[0037] In these embodiments, the LCP may be made exclusively from the following monomers: 6-hydroxy-2-naphthoic acid (HNA) (or derivative), biphenol (BP) (or derivative), hydroquinone (HQ) (or derivative), cyclohexanedicarboxylic acid (CHDA) (or derivative), 2,6-naphthalenedicarboxylic acid (NDA) (or derivative), bibenzoic acid (BB) (or derivative).

[0038] For example, an LCP of the present invention is such that the number of moles of repeating units is as follows: Formula (I)+(II)+(III)=100 mol %, for example Formula (I)+(IIa)+(IIIa)=100 mol %, Formula (I)+(II)+(III)+(IV)=100 mol %, for example Formula (I)+(IIa)+(IIIa)+(IV)=100 mol %, the formula (I)+(II)+(III)+(V)=100 mol %; the total of the formula (I)+(II)+(III)+(VI)=100 mol %; the total of the formula (I)+(II)+(III)+(IX)=100 mol %, or Formula (I)+(II)+(III)+(X)=100 mol % It could be something like this.

[0039] In some embodiments, the LCP may be made exclusively from the following monomers: 6-hydroxy-2-naphthoic acid (HNA) (or derivative), biphenol (BP) (or derivative), cyclohexanedicarboxylic acid (CHDA), preferably 1,4-CHDA, and 2,6-naphthalenedicarboxylic acid (NDA) (or derivative).

[0040] The LPC of the present invention is prepared from a variety of entities, some of which are diols, dicarboxylic acids, hydroxycarboxylic acids, esters, or diesters. The term "diol" refers to an organic compound having two hydroxyl groups, preferably having no other functional groups capable of forming an ester bond. The term "dicarboxylic acid" refers to an organic compound having two carboxyl groups, preferably having no other functional groups capable of forming an ester bond. The term "hydroxycarboxylic acid" refers to an organic compound having one hydroxyl group and one carboxyl group, preferably having no other functional groups capable of forming an ester bond. The term "ester" or "diester" refers to an organic compound having one or two carboxyl groups (R ) derived from a carboxylic acid. 1 CO2-, where R 1 In other words, the LPC of the present invention refers to an organic compound having [—OH], [—OCOR], 1 In some embodiments, the LCP is prepared from monomers having a molar ratio ([-OH] + [-COOH]) ranging from 0.8 to 1.2, preferably from 0.9 to 1.1, and even more preferably from 0.95 to 1.05. 1]) / [—COOH]. By way of example, according to these embodiments, the molar ratio of repeating units ([II]+[XI]+[XII]) / repeating units ([III]+[IV]+[V]+[VI]+[IX]+[X]) is equal to 1±0.2, preferably 1±0.1, more preferably 1±0.05, and even more preferably 1±0.01.

[0041] According to certain embodiments, the LCPs described herein have a melting temperature (Tm) greater than 260°C, e.g., 260-320°C, e.g., 270-310°C, or in the range of 280-300°C, as measured using differential scanning calorimetry (DSC) according to ASTM D3418 (cooling, 20°C / min heating / cooling rate).

[0042] According to certain embodiments, the LCPs described herein have a crystallization temperature (Tc) of less than 260°C, e.g., in the range of 150-260°C, e.g., 155-250°C, or 160-246°C, or 160-240°C, as measured using differential scanning calorimetry (DSC) according to ASTM D3418 (cooling, 20°C / min heating / cooling rate).

[0043] According to one embodiment, the LCP or thermoplastic composition (C), the article of the present invention preferably has a dielectric constant Dk at 5 GHz of less than 3.5, preferably less than 3.4, or 3.3 or less, as measured in the in-plane direction on a 4 cm x 4 cm x 150 μm (thickness) film obtained from a "dry-as-molded" compression molded film using a Split Cylinder Resonator (SCR method) according to ASTM D2520 (5 GHz).

[0044] According to one embodiment, the LCP or thermoplastic composition (C), the article of the present invention preferably has a dielectric loss tangent Df at 5 GHz of less than 0.0060, preferably less than 0.0058, or 0.0055 or less, as measured in the in-plane direction on a 4 cm x 4 cm x 150 μm (thickness) film obtained from a "dried as-molded" compression molded film using a split cylinder resonator (SCR method) according to ASTM D2520 (5 GHz).

[0045] According to one embodiment, the LCP or thermoplastic composition (C), article of the present invention preferably has a dielectric constant Dk at 20 GHz of less than 3.6, preferably less than 3.5, or 3.4 or less, as measured in the in-plane direction on a 4 cm x 4 cm x 150 μm (thickness) film obtained from a "dried as-molded" compression molded film using a split cylinder resonator (SCR method) according to ASTM D2520 (20 GHz).

[0046] According to one embodiment, the LCP or thermoplastic composition (C), article of the present invention preferably has a dielectric loss tangent (Df) at 20 GHz of less than 0.0030, preferably less than 0.0025, or 0.0020 or less, as measured in the in-plane direction on a 4 cm x 4 cm x 150 μm (thickness) film obtained from a "dried as-molded" compression-molded film using a split cylinder resonator (SCR method) according to ASTM D2520 (20 GHz). The LCP or thermoplastic composition (C), article of the present invention more preferably has a dielectric loss tangent (Df) at 20 GHz of 0.0010 to 0.0020 or 0.0011 to 0.0019.

[0047] The LCPs described herein can be prepared by any conventional method adapted to the synthesis of polyesters, and more specifically, LCPs.

[0048] The LCPs described herein can be prepared, for example, by thermal polycondensation of monomers and comonomers. The LCPs can contain chain limiters, which are monofunctional molecules capable of reacting with hydroxyl or carboxylic acid moieties and are used to control the molecular weight of the LCP. For example, the chain limiter can be acetic acid, propionic acid, and / or benzoic acid. Catalysts can also be used. Examples of catalysts are phosphorous acid, ortho-phosphoric acid, meta-phosphoric acid, alkali metal hypophosphites such as sodium hypophosphite, and phenylphosphinic acid. Stabilizers, such as phosphites, can also be used.

[0049] The LCP described herein can also be advantageously prepared by a solventless process, i.e., a process carried out in a melt without the presence of a solvent.When the condensation is carried out without a solvent, the reaction can be carried out in an apparatus made of a material inert to the monomer.In this case, the apparatus is selected to provide sufficient contact of the monomer, and the apparatus allows removal of volatile reaction products.Suitable apparatuses include stirred reactors, extruders, and kneaders.

[0050] Thermoplastic composition (C) The LCPs described herein may be present in thermoplastic composition (C) in a total amount of greater than 30 wt%, greater than 35 wt%, greater than 40 wt%, or greater than 45 wt%, based on the total weight of thermoplastic composition (C).

[0051] The LCP may be present in thermoplastic composition (C) in a total amount of less than 99.95 wt%, less than 99 wt%, less than 95 wt%, less than 90 wt%, less than 80 wt%, less than 70 wt%, or less than 60 wt%, based on the total weight of thermoplastic composition (C).

[0052] The LCP may be present in the thermoplastic composition (C) in an amount ranging from 30 to 90% by weight, for example, from 40 to 80% by weight, based on the total weight of the thermoplastic composition (C).

[0053] The thermoplastic composition (C) may also comprise one or more components selected from the group consisting of fillers (such as reinforcing agents), toughening agents, impact modifiers, plasticizers, colorants, pigments, antistatic agents, dyes, lubricants, heat stabilizers, light stabilizers, flame retardants, nucleating agents, and antioxidants.

[0054] A wide variety of fillers (also called reinforcing fibers or reinforcing fillers, such as reinforcing agents) can be added to the composition (C) according to the present invention. They can be selected from fibrous reinforcing agents and particulate reinforcing agents. Fibrous reinforcing fillers are considered herein to be materials having a length, width, and thickness in which the average length is significantly greater than both the width and thickness. Generally, such materials have an aspect ratio, defined as the average ratio between the length and the maximum width and thickness, of at least 5, at least 10, at least 20, or at least 50. Fillers can generally be selected from mineral fillers (e.g., talc, mica, kaolin, calcium carbonate, calcium silicate, magnesium carbonate, etc.), glass fibers, carbon fibers, synthetic polymer fibers, aramid fibers, aluminum fibers, titanium fibers, magnesium fibers, boron carbide fibers, rock wool fibers, steel fibers, and wollastonite. The fillers can be, for example, low-dielectric-constant fibrous fillers or hollow fillers. The fillers can be conductive and non-conductive thermally conductive fillers, such as boron nitride, zinc oxide, or graphene. In some embodiments, thermoplastic composition (C) comprises either boron nitride or zinc oxide. In one such embodiment, thermoplastic composition (C) comprises boron nitride and no zinc oxide. In other embodiments, thermoplastic composition (C) comprises zinc oxide and no boron nitride. As used herein, and unless expressly stated otherwise, "free of" a component means that the concentration of that component is 1 wt% or less, 0.5 wt% or less, 0.1 wt% or less, or 0.05 wt% or less, based on the total weight of thermoplastic composition (C).

[0055] The fillers (such as reinforcing agents) may be present in thermoplastic composition (C) in a total amount of more than 5 wt%, more than 10 wt%, more than 15 wt%, or more than 20 wt%, based on the total weight of thermoplastic composition (C). The fillers may be present in composition (C) in a total amount of less than 65 wt%, less than 60 wt%, less than 55 wt%, or less than 50 wt%, based on the total weight of polymer composition (C).

[0056] The filler may be present in the thermoplastic composition (C) in an amount ranging from 5 to 65% by weight, for example from 10 to 55% by weight, based on the total weight of the composition (C).

[0057] In some embodiments, the composition (C) of the present invention may include a low dielectric constant fibrous filler, specifically a low dielectric constant glass fiber filler. It is desirable for the low dielectric constant filler to have a low dielectric loss tangent (Df). Specifically, the low dielectric constant filler may have a Dk of less than 5.0 (about 4.5) at frequencies between 1 megahertz (MHz) and 1 GHz and a Df of less than about 0.002 at frequencies between 1 MHz and 1 GHz. In certain examples, the low dielectric constant filler is a dielectric glass fiber having a Dk of less than 5.0 at frequencies between 1 MHz and 1 GHz and a Df of less than about 0.002 at frequencies between 1 MHz and 1 GHz.

[0058] In an exemplary embodiment, composition (C) comprises glass fibers, e.g., low dielectric constant fibrous fillers, which may be selected from E-glass, S-glass, AR-glass, T-glass, D-glass, R-glass, and combinations thereof. By way of example, the glass fibers may be of the "E" glass type, which is a glass of fibrous glass filaments contained in lime-alumino-borosilicate glass.

[0059] The glass fibers, e.g., low dielectric constant glass fibers, that can be used in the composition (C) of the present invention can have a variety of shapes. The fibers can include milled or chopped glass fibers. They can be in the form of whiskers or flakes. In a further example, they can be short or long glass fibers. Glass fibers can have a length of about 4 mm (millimeters) or more and are referred to as long fibers, while fibers shorter than this are referred to as short fibers. In one embodiment, the diameter of the glass fibers can be 10 μm (microns), or 2 μm to 15 μm, or 5 μm to 12 μm.

[0060] Glass fibers, such as low-dielectric-constant glass fibers, can have circular, flat, or irregular cross sections. Glass fibers having non-circular cross sections can be used in the compositions of the present invention. Alternatively, the glass fibers can have a circular cross section. The diameter of the glass fibers can be, for example, about 1 to about 15 μm. More specifically, the diameter of the low-dielectric-constant glass fibers can be, for example, about 4 to about 10 μm. Flat glass fibers, such as Nitto Boseki's flat glass fiber (CSG 3PA-830), can also be used.

[0061] The filler that may be present in the composition (C) of the present invention may be surface-treated with a surface treatment agent containing a coupling agent to improve adhesion to the polymer base resin. Suitable coupling agents include, but are not limited to, silane-based coupling agents, titanate-based coupling agents, or mixtures thereof. Applicable silane-based coupling agents include aminosilanes, epoxysilanes, amidosilanes, and acrylic silanes. Organometallic coupling agents, such as titanium- or zirconium-based organometallic compounds, may also be used.

[0062] The composition (C) of the present invention may also contain a hollow filler. The hollow filler may be, for example, hollow glass spheres, hollow glass fibers, or hollow ceramic spheres. In a specific example, the hollow filler may be hollow glass spheres. An exemplary hollow glass sphere has a density of 0.2 grams per cubic centimeter (g / cm). 3For example, suitable hollow glass spheres have a density of about 0.46 g / cm 3 In a further example, suitable hollow glass spheres have a density of about 0.6 g / cm 3 The hollow glass spheres have a diameter of 5 μm to 50 μm. For example, suitable hollow glass spheres have a diameter of about 30 μm ± 2, or about 20 μm ± 2. Other suitable hollow glass spheres have a diameter of about 10 μm ± 2.

[0063] The thermoplastic composition (C) of the present invention may also contain a toughening agent, also called an impact modifier. Toughening agents are generally low glass transition temperature (Tg) polymers, for example, Tg below room temperature, below 0°C, or even below -25°C. As a result of their low Tg, toughening agents are typically elastomeric at room temperature. Toughening agents can be functionalized polymer backbones.

[0064] The toughening agent can be, for example, a siloxane-based toughening agent.

[0065] The polymer backbone of the toughening agent may be selected from elastomeric backbones comprising polyethylene and copolymers thereof, such as ethylene-butene, ethylene-octene; polypropylene and copolymers thereof; polybutene; polyisoprene; ethylene-propylene rubber (EPR); ethylene-propylene-diene monomer rubber (EPDM); ethylene-acrylate rubber; butadiene-acrylonitrile rubber, ethylene-acrylic acid (EAA), ethylene-vinyl acetate (EVA); acrylonitrile-butadiene-styrene rubber (ABS); block copolymer styrene-ethylene-butadiene-styrene (SEBS); block copolymer styrene-butadiene-styrene (SBS); core-shell elastomers of the methacrylate-butadiene-styrene (MBS) type, or mixtures of one or more of the above.

[0066] When the toughening agent is functionalized, the backbone functionalization can result from copolymerization of monomers containing the functionalization or from grafting the polymer backbone with additional components.

[0067] Specific examples of functionalized toughening agents are, inter alia, terpolymers of ethylene, acrylic esters and glycidyl methacrylate, copolymers of ethylene and butyl ester acrylate; copolymers of ethylene, butyl ester acrylate and glycidyl methacrylate; ethylene-maleic anhydride copolymers; EPR grafted with maleic anhydride; styrene copolymers grafted with maleic anhydride; SEBS copolymers grafted with maleic anhydride; styrene-acrylonitrile copolymers grafted with maleic anhydride; ABS copolymers grafted with maleic anhydride.

[0068] The toughening agent may be present in thermoplastic composition (C) in a total amount of more than 1 wt%, more than 2 wt%, or more than 3 wt%, based on the total weight of thermoplastic composition (C). The toughening agent may be present in thermoplastic composition (C) in a total amount of less than 30 wt%, less than 20 wt%, less than 15 wt%, or less than 10 wt%, based on the total weight of thermoplastic composition (C).

[0069] The thermoplastic composition (C) may also contain other conventional additives commonly used in the art, such as plasticizers, colorants, pigments (e.g., black pigments such as carbon black and nigrosine), antistatic agents, dyes, lubricants (e.g., linear low-density polyethylene, calcium or magnesium stearate, or sodium montanate), heat stabilizers, light stabilizers, flame retardants, nucleating agents, mold release agents, and antioxidants.

[0070] In various embodiments, the thermoplastic composition (C) can include a release agent. Exemplary release agents include, for example, metal stearates, stearyl stearate, pentaerythritol tetrastearate, beeswax, montan wax, paraffin wax, and the like, or a combination comprising at least one of the foregoing release agents. The release agent is generally used in an amount of about 0.1 to about 1.0 parts by weight, based on 100 parts by weight of the total thermoplastic composition (C), excluding any fillers.

[0071] The thermoplastic composition (C) may also contain one or more other polymers, such as an LCP distinct from the LCP of the present invention, or, for example, polyethylene glycol (PEG), polyethylene terephthalate (PET), or polyethylene naphthalate (PEN).

[0072] Preparation of Thermoplastic Composition (C) A method for producing the thermoplastic composition (C) as detailed above is also described herein. In fact, the thermoplastic composition (C) of the present invention can be prepared according to various methods. The compositions of the present disclosure can be blended, compounded, or otherwise combined with the aforementioned ingredients by various methods, including intimate mixing / combining of the materials with any additional additives desired in the formulation. The preparation method includes, for example, melt-blending the LCP with certain components, such as fillers, reinforcing agents, stabilizers, and any other optional additives.

[0073] Any melt blending method can be used to mix the polymeric and non-polymeric ingredients relevant to the present invention. For example, the polymeric and non-polymeric ingredients can be fed into a melt mixer such as a single-screw or twin-screw extruder, a stirrer, a single-screw or twin-screw kneader, or a Banbury mixer, and the addition step can be simultaneous addition of all ingredients or gradual batch-wise addition. When the polymeric and non-polymeric ingredients are added gradually batch-wise, a portion of the polymeric and / or non-polymeric ingredients is added first, and then melt-mixed with the remaining polymeric and non-polymeric ingredients added thereafter until a well-mixed composition is obtained. When the reinforcing agent has a long physical shape (e.g., long glass fiber), stretch extrusion molding can be used to prepare the reinforced thermoplastic composition (C).

[0074] Articles and end use The present invention relates to articles comprising the LCP or thermoplastic composition (C) described herein.

[0075] The LCP or thermoplastic composition (C) of the present invention can be in various forms. For example, they can be in powder form, fiber form, or particulate form. They can also be in liquid form.

[0076] Any process known to those skilled in the art can be used to produce powders, fibers, or particles of LCP, including mechanical, solution, and melt methods. Mechanical processes include grinding and milling of LCP (e.g., cryogenic grinding, jet milling, ball milling, etc.). Solution processing includes coagulation / precipitation of soluble or semi-soluble LCP (e.g., solution coagulation or prilling). Fibers can be produced by melt spinning, solution spinning, etc. Fibers can be either monofilaments or bicomponent filaments, such as core-sheath and side-by-side.

[0077] The LCP or thermoplastic composition (C) of the present invention can be used as a filler or additive in dispersions, solutions, films and injection molded specimens.

[0078] For example, the powders can be used as additives in dispersions, particularly polyamide / polyimide solutions, LCP solutions, or polysulfone solutions. They can also be used as matrices for fusing into films or 3D objects. They can also be used as materials for injection molding, for example, narrow-pitch connectors, thin-walled parts, cases, microswitches, and structural materials for cameras. They can also be used as fillers / additives in resins for injection-molded parts, such as structural components, antennas, and base station articles.

[0079] The fibers can be used as staple fibers in spunbonding processes and chopped as reinforcement / fillers. With respect to fibers, potential processes for producing the fibers include melt spinning, solution spinning, etc. They can be either monofilaments or bicomponent filaments (e.g., core-sheath, side-by-side).

[0080] The LCP or thermoplastic composition (C) of the present invention can be shaped into a film, for example in the form of a flexible printed circuit board (FPC).

[0081] The LCP or thermoplastic composition (C) may also be injection molded for structural components of microelectronics and smart devices, portable electronic devices, i.e., electronic devices intended to be conveniently carried and used in a variety of locations. Portable electronic devices may include, but are not limited to, mobile phones, personal digital assistants ("PDAs"), laptop computers, tablet computers, wearable computing devices (e.g., smart watches, smart glasses, etc.), cameras, portable audio players, portable radios, global positioning system receivers, and portable game consoles.

[0082] The LCPs and thermoplastic compositions (C) described herein achieve dielectric performance that can be attributed to a synergistic effect between the LCP components. The LCPs and thermoplastic compositions (C) of the present invention also exhibit an advantageous set of thermal properties (e.g., Tm and Tc) while maintaining liquid crystal morphology. This is particularly desirable for forming LCP films. More precisely, the inventors have realized that the LCPs of the present invention exhibit a set of Tc and Tm that makes them suitable for processing in the form of films. In particular, as described above, their Tc is preferably less than 260°C, and their Tm is greater than 260°C. The LCPs of the present invention can withstand assembly processing steps in the microelectronic space. Various lamination / surface mount technologies (SMT) use temperatures greater than 260°C; therefore, it is clearly advantageous for the present LCPs to have a Tm greater than 260°C, e.g., about 280°C to 300°C.

[0083] According to some embodiments, the portable electronic device component may include, for example, a wireless antenna and composition (C). In this case, the wireless antenna may be a WiFi antenna or an RFID antenna. The portable electronic device component may also be an antenna housing.

[0084] In some embodiments, the portable electronic device component is an antenna housing. In some such embodiments, at least a portion of a wireless antenna is disposed on the thermoplastic composition (C). Additionally or alternatively, at least a portion of the wireless antenna may be replaced by the thermoplastic composition (C). In some embodiments, the device component can be an attachment component having mounting holes or other fastening devices (including, but not limited to, a snap-fit ​​connector between itself and another component of the portable electronic device, including, but not limited to, a circuit board, a microphone, a speaker, a display, a battery, a cover, a housing, an electrical or electronic connector, a hinge, a wireless antenna, a switch, or a switch pad). In some embodiments, the portable electronic device can be at least a portion of an input device.

[0085] In some embodiments, the portable electronic device parts or components are used in transportation, such as automobiles (e.g., smart cars / 5G-enabled intelligent cars), aeronautical articles, and drones.

[0086] In a further embodiment, the molded article can be used to manufacture articles, devices, or components in the transportation field, especially in the automotive field. In a further embodiment, non-limiting examples of such devices in the automotive field that can use the blended thermoplastic composition (C) of the present disclosure in the interior of a vehicle include adaptive cruise control, headlight sensors, windshield wiper sensors, and door / window switches. In a further embodiment, non-limiting examples of devices in the automotive field that can use the blended thermoplastic composition (C) of the present disclosure in the exterior of a vehicle include pressure and flow sensors for engine management, air conditioning, collision detection, and exterior lighting fixtures.

[0087] The disclosures of all patent applications and publications cited herein, to the extent that they provide exemplary, procedural, or other details supplementary to those set forth herein, are hereby incorporated by reference. To the extent that the disclosures of any patents, patent applications, and publications incorporated herein by reference conflict with the statements of this application to the extent that a term may be unclear, the present statement shall control. [Example]

[0088] These examples demonstrate the thermal and dielectric performance of inventive and comparative LCPs.

[0089] raw materials AcHNA: 6-acetoxy-2-naphthoic acid, commercially available from TCI (Tokyo Chemical Industry Co., Ltd.). AcBP: 4,4'-diacetoxybiphenyl, commercially available from TCI. CHDA: 1,4-cyclohexanedicarboxylic acid, commercially available from Sigma Aldrich (cis / trans ratio is 78.5:21.5) NDA: 2,6-naphthalenedicarboxylic acid, commercially available from TCI. 4,4'-BB: 4,4'-bibenzoic acid, commercially available from TCI.

[0090] Comparison LCP resin 1 The reaction was carried out in a dry 100 mL round-bottom flask equipped with an overhead stirrer, a nitrogen inlet, and a distillation neck attached to a receiving flask. 33.68 g of AcHNA (70 mol%), 5.40 g of CHDA (15 mol%), and 8.47 g (15 mol%) of AcBP were added. Subsequent degassing with vacuum and N2 gas purging (3x) created an oxygen-free environment. The initial temperature was 220 °C, or the temperature at which all monomers formed a melt, and this temperature was maintained with stirring for 0.5 h. The temperature was increased from the starting temperature to 335 °C at 1.0 °C / min and held there for 1 h. House vacuum was then applied for 0.5–1 h to facilitate removal of acetic acid condensate, followed by application of high vacuum, reaching 0.1–2 mmHg. The reaction was held under high vacuum until no significant condensation was observed from the reaction and the polymer sample solidified around the stirrer blade. The sample was then cooled and recovered from the stirrer blade. The LCP was dried overnight at 100°C before use.

[0091] Invention LCP resin 2 This example follows the previous procedure using a monomer charge of 33.07 g (70 mol%) AcHNA, 3.11 g (7 mol%) NDA, 2.83 g (8 mol%) CHDA, and 8.32 g (15 mol%) AcBP.

[0092] Comparison LCP resin 3 This example follows the previous procedure using a monomer charge of 29.02 g (60 mol%) AcHNA, 7.24 g (20 mol%) CHDA, and 11.36 g (20 mol%) AcBP.

[0093] Invention LCP resin 4 This example follows the previous procedure using a monomer charge of 32.72 g (70 mol%) AcHNA, 3.44 g (7 mol%) 4,4'BB, 2.80 g (8 mol%) CHDA, and 8.23 ​​g (15 mol%) AcBP.

[0094] Invention LCP resin 5 This example follows the previous procedure as in Inventive LCP Resin 2, but using 70 mol % AcHNA, 15 mol % AcBP, 10 mol % NDA, and 5 mol % CHDA as the monomer charge.

[0095] Film preparation Compression molding utilized two stainless steel plates layered with Kapton film and aluminum shims to control thickness (0.004 inches). Before placing the top plate, the sample was heated to Tm+20°C for approximately 3 minutes. The sandwich was placed in the center of the press, which was closed to ensure contact with both the top and bottom plates. After 2 minutes of heating at Tm+20°C, the film compression molding procedure was completed with four press-release-press cycles, using 2 tons of force for the first two cycles and 4 tons of force for the last two cycles. The sandwich was immediately removed from the press, placed on a cold bench, and allowed to return to ambient temperature for at least 1 hour. The film was then removed from the sandwich and placed in an inert oven using N2 gas and annealed at 200°C for 18 hours.

[0096] test Thermal transition (Tg, Tm) The glass transition temperatures and melting temperatures of various LCPs were measured using differential scanning calorimetry according to ASTM D3418 using a heating and cooling rate of 20°C / min. Three scans were used for each DSC run: a first heat to 340°C, followed by a first cool to 30°C, followed by a second heat to 350°C. Tm was determined from the second heat and Tc was determined from the cool. The melting temperatures are listed in Table 1 below.

[0097] Compression molding and dielectric performance Compression molding of 4 inch x 4 inch x 0.006 inch squares was performed on the dry granular polymer using a Carver 8393 Laboratory Press. The dielectric constant Dk and dissipation factor Df were measured on 4 cm x 4 cm x 150 μm (thick) films obtained from the "dry as molded" compression molded films. The dielectric constant Dk and dissipation factor Df in the in-plane direction were measured using a split cylinder resonator (SCR method) according to ASTM D2520.

[0098] result Films made from inventive resins 2, 4, and 5 (with 5-8 mol% CHDA) had dissipation factors at 20 GHz of 0.0011-0.0019, while films made from comparative resins 1 and 3 (with 15 and 20 mol% CHD) had higher dissipation factors at 20 GHz, Df, of 0.0031 and 0.0046.

[0099] [Table 1]

Claims

1. A liquid crystal polyester (LCP), comprising, based on the total number of moles in the LCP: 40 to 98 mol % of formula (I): 【Chemistry 1】 Repeating units of 1 to 20 mol % of formula (II): 【Chemistry 2】 Repeating units of 1 to 9.5 mol % of formula (III): 【Transformation 3】 An LCP comprising repeating units of

2. 0.1 to 15 mol % of formula (IV): 【Chemistry 4】 Repeating units of 0.1 to 15 mol % of formula (V): 【Transformation 5】 and / or a repeating unit of 0.1 to 15 mol % of formula (VI): 【Transformation 6】 10. The LCP of claim 1 further comprising a repeat unit of:

3. 0.1 to 15 mol % of formula (VII): 【Transformation 7】 Repeating units of 0.1 to 15 mol % of formula (VIII): 【Transformation 8】 Repeating units of 0.1 to 15 mol % of formula (IX): 【Chemistry 9】 Repeating units of 0.1 to 15 mol % of formula (X): 【Chemistry 10】 and / or a repeating unit of 0.1 to 15 mol % of formula (XI): 【Chemistry 11】 and / or a repeating unit of 0.1 to 15 mol % of formula (XII): 【Chemistry 12】 3. The LCP of claim 1, further comprising a repeat unit of:

4. - 40 to 90 mol % of repeat units of formula (I), - 10 to 20 mol % of repeat units of formula (II), and - 2 to 9.5 mol % of repeat units of formula (III) The LCP according to any one of claims 1 to 3, comprising:

5. - 65 to 85 mol % of repeat units of formula (I), - 13 to 18 mol % of repeat units of formula (II), and - 3 to 9.5 mol % of repeat units of formula (III), Optionally, the following repeat unit: - 1 to 11 mol % of repeat units of formula (IV), - 1 to 11 mol % of repeat units of formula (V), and / or - 1 to 11 mol % of repeat units of formula (VI) The LCP according to any one of claims 1 to 4, comprising any one of:

6. The number of moles of repeating units is formula (I)+(II)+(III)=100 mol %; the formula (I)+(II)+(III)+(IV)=100 mol %; the formula (I)+(II)+(III)+(V)=100 mol %; the formula (I)+(II)+(III)+(VI)=100 mol %; the formula (I)+(II)+(III)+(IX)=100 mol %; Formula (I) + (II) + (III) + (X) = 100 mol % The LCP according to any one of claims 1 to 5.

7. 40 to 98 mol % of 6-hydroxy-2-naphthoic acid (HNA) and / or 6-acetoxy-2-naphthoic acid (AcHNA), 1 to 20 mol % of 4,4′-biphenol (BP), hydroquinone (HQ), 4,4′-diacetoxybiphenyl (AcBP) and / or 1,4-diacetoxybenzene (AcHQ), and 1 to 9.5 mol % of cyclohexanedicarboxylic acid (CHDA), 7. The LCP according to claim 1, resulting from the condensation of

8. Molar ratio ([-OH] + [-OCOR １ ]) / [—COOH] is in the range of 0.8 to 1.2, １ 8. An LCP according to claim 1, resulting from the condensation of a monomer having [—COOH] and [—COOH].

9. A thermoplastic composition (C) comprising the LCP of any one of claims 1 to 8 and optionally at least one component selected from the group consisting of reinforcing agents, toughening agents, plasticizers, colorants, pigments, antistatic agents, dyes, lubricants, heat stabilizers, light stabilizers, flame retardants, nucleating agents, and antioxidants.

10. A portable electronic device article or component comprising an LCP according to any one of claims 1 to 8 or a thermoplastic composition according to claim 9.

11. The LCP or the thermoplastic composition (C) a dielectric constant Dk at 5 GHz of less than 3.5, as measured according to ASTM D2520 (5 GHz), and / or a dissipation factor Df at 5 GHz of less than 0.0060, as measured according to ASTM D2520 (5 GHz), and / or a dielectric constant Dk at 20 GHz of less than 3.6, as measured according to ASTM D2520 (20 GHz), and / or - Dissipation factor Df at 20 GHz less than 0.0030 as measured in accordance with ASTM D2520 (20 GHz) 11. The article or component of claim 10, having:

12. 12. An article or component according to claim 10 or 11 in the form of a film.

13. Use of the liquid crystal polyester (LCP) according to any one of claims 1 to 8 or the thermoplastic composition according to claim 9 for preparing a portable electronic device article or component.

14. Use of a liquid crystalline polyester (LCP) according to any one of claims 1 to 8 or a thermoplastic composition according to claim 9 for preparing a device, article or component used for transportation.

15. 1. Use of cyclohexanedicarboxylic acid (CHDA) for preparing a liquid crystal polyester (LCP) comprising at least 40 to 98 mole % of 6-hydroxy-2-naphthoic acid (HNA) or 6-acetoxy-2-naphthoic acid (AcHNA) and at least 1 to 20 mole % of one dihydroxy aromatic compound, wherein CHDA is in a molar ratio varying between 1 and 9.5 mole %, based on the total number of moles in the LCP.

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