Liquid crystal polyester, method for producing liquid crystal polyester, pellets, and molded article

Abstract

The liquid crystal polyester has a peak position (G) of 4.50-4.87 (inclusive) as calculated by formula (1), and a peak top of a molecular weight distribution curve of 5.05 or more in terms of log (M) value. [In formula (1), A1, A2, [mu] 1, and [mu] 2 each represent a value obtained by fitting a molecular weight distribution curve measured by GPC (longitudinal axis: differential molecular weight distribution, and horizontal axis: logarithm of molecular weight converted from polystyrene with the base being 10) with formula (2) at [mu] 1 < [mu] 2. ] (In formula (2), M represents the molecular weight, and log (M) represents the logarithm of the molecular weight. ] [Mathematical formula 1] [Mathematical formula 2].

Description

Technical Field

[0001] This disclosure relates to liquid crystal polyester, methods for manufacturing liquid crystal polyester, granules, and molded articles. Background Technology

[0002] Liquid crystal polyester is used in a variety of applications due to its fluidity, heat resistance and high dimensional accuracy.

[0003] For example, Patent Document 1 describes a liquid crystal polymer composition containing 15% by mass or more of a specific flat glass fiber and 20% by mass or more of a specific plate-shaped filler.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2003-268252 Summary of the Invention

[0005] The problem that the invention aims to solve In recent years, from the perspective of expanding into more diverse applications and using it in more sophisticated components, there has been a demand to improve the properties of liquid crystal polyester itself.

[0006] The purpose of this disclosure is to provide a liquid crystal polyester that can balance good flowability during melting and excellent mechanical properties of the molded article. Another purpose of this disclosure is to provide a method for manufacturing the liquid crystal polyester, as well as granules and molded articles comprising the liquid crystal polyester.

[0007] Methods for solving problems This disclosure provides, for example, the following solutions.

[0008] [1] A liquid crystal polyester, wherein the peak position (G) calculated by equation (1) is above 4.50 and below 4.87. The peak of the molecular weight distribution curve is above 5.05 in terms of log(M) value.

[0009] [Mathematical Expression 1] [In equation (1), A1, A2, μ1, and μ2 represent the values ​​when the molecular weight distribution curve (vertical axis: differential molecular weight distribution, horizontal axis: logarithm of the molecular weight converted from polystyrene with a base of 10) obtained by GPC is fitted with the following equation (2) with μ1 < μ2.] [Mathematical Expression 2] [In equation (2), M represents the molecular weight, and log(M) represents the logarithm of the molecular weight.] [2] According to the liquid crystal polyester of [1], wherein the peak of the above molecular weight distribution curve is 5.05 or more and 5.30 or less in terms of log(M).

[0010] [3] The liquid crystal polyester according to [1] or [2], wherein A1 < A2.

[0011] [4] The liquid crystal polyester according to any one of [1] to [3], wherein the weight-average molecular weight (Mw) is 100,000 or more and 250,000 or less.

[0012] [5] The liquid crystal polyester according to any one of [1] to [4], wherein the number average molecular weight (Mn) is 35,000 or more and 60,000 or less.

[0013] [6] The liquid crystal polyester according to any one of [1] to [5], wherein the ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) (Mw / Mn) is 3.20 or more and 3.96 or less.

[0014] [7] The liquid crystal polyester according to any one of [1] to [6] contains a first monomer unit having a fused aromatic ring and a second monomer unit having a benzene ring.

[0015] [8] The liquid crystal polyester according to [7], wherein the fused aromatic ring is a naphthalene ring.

[0016] [9] The liquid crystal polyester according to any one of [1] to [8] contains two or more liquid crystal polyesters.

[0017]

[10] The liquid crystal polyester according to any one of [1] to [9] comprises: The first liquid crystal polyester with the first molecular weight distribution curve, and The second liquid crystal polyester having a second molecular weight distribution curve The log(M) value of the peak of the first molecular weight distribution curve is less than the log(M) value of the peak of the second molecular weight distribution curve.

[0018]

[11] A method for manufacturing a liquid crystal polyester, which is a method for manufacturing the liquid crystal polyester described in any one of [1] to

[10] , wherein, This includes a process of mixing two or more liquid crystal polyesters.

[0019]

[12] According to the manufacturing method described in

[11] , the above-mentioned step is a step of mixing a first liquid crystal polyester having a first molecular weight distribution curve and a second liquid crystal polyester having a second molecular weight distribution curve. The log(M) value of the peak of the first molecular weight distribution curve is less than the log(M) value of the peak of the second molecular weight distribution curve.

[0020]

[13] A granule comprising any one of [1] to

[10] liquid crystal polyester.

[0021]

[14] A molded article comprising any one of the liquid crystal polyesters described in [1] to

[10] , The molded products include connectors, sockets, relay components, coil frames, optical pickups, oscillators, semiconductor packages, IC trays, wafer carriers, components for household appliances, lighting fixtures, audio equipment, fiber optic cable clamps, telephone components, fax components, modem components, release claws, heater brackets, impellers, fan gears, gears, bearings, motor components, motor housings, engine components, engine compartment components, electrical components, automotive interior trim components, microwave cooking pots, heat-resistant tableware, flooring materials, wall materials, beams, columns, roofing materials, aircraft components, spacecraft components, aerospace equipment components, nuclear reactors, marine facility components, washing fixtures, optical equipment components, valves, pipes, nozzles, filters, membranes, medical equipment components, medical materials, sensor components, sanitary spare parts, and sporting or leisure products.

[0022] Invention Effects According to this disclosure, a liquid crystal polyester that can balance good flowability during melting and excellent mechanical properties of the molded article can be provided. Furthermore, according to this disclosure, a method for manufacturing the polyester, as well as granules and molded articles comprising the liquid crystal polyester, can also be provided. Attached Figure Description

[0023] Figure 1 This is a graph showing the molecular weight distribution curve of Example 1. Detailed Implementation

[0024] The following describes in detail suitable embodiments of this disclosure.

[0025] The liquid crystal polyester of this embodiment (hereinafter also referred to as "liquid crystal polyester") is a liquid crystal polyester with a peak position (G) of 4.50 or more and 4.87 or less calculated by formula (1) and a log (M) value of 5.05 or more at the peak of the molecular weight distribution curve.

[0026] [Mathematical Expression 3] [In equation (1), A1, A2, μ1, and μ2 represent the values ​​when the molecular weight distribution curve (vertical axis: differential molecular weight distribution, horizontal axis: logarithm of the molecular weight converted from polystyrene with a base of 10) obtained by GPC is fitted with the following equation (2) with μ1 < μ2.] [Mathematical Expression 4] [In equation (2), M represents the molecular weight, and log(M) represents the logarithm of the molecular weight.] The liquid crystal polyester of this embodiment exhibits good fluidity when melted, and the molded articles possess excellent mechanical properties (tensile strength, nominal strain at tensile break). Furthermore, the liquid crystal polyester of this embodiment has a high flexural temperature, making it a molding material that combines moldability, mechanical properties, and heat resistance.

[0027] The inventors investigated the peak position (G) as a variable represented by equation (1) and found that by making the values ​​of the peak position (G) and the peak value within a specific range, a liquid crystal polyester with good mechanical properties and heat resistance and good flowability when melted can be obtained.

[0028] From the viewpoint of improving the mechanical properties and heat resistance of liquid crystal polyester, it is preferable to contain high molecular weight molecular chains in the liquid crystal polyester. From the viewpoint of improving the flowability of liquid crystal polyester, it is preferable to contain low molecular weight molecular chains in the liquid crystal polyester. It can be considered that the liquid crystal polyester of this embodiment can produce the above-mentioned effects because the values ​​of peak position (G) and peak apex are within a specific range and it contains a good balance of high molecular weight molecular chains and low molecular weight molecular chains.

[0029] The above molecular weight distribution curve is a converted molecular weight distribution curve of polystyrene obtained using GPC, and it was measured under the following conditions.

[0030] <Preparation of the determination solution> Add 3.4 g of pentafluorophenol (PFP) to 4.86 mg of a sample prepared by cryogenic pulverization, and dissolve at 120–125 °C for 2 hours while stirring. After cooling to 40–50 °C, add 6.3 g of chloroform, stir, and filter through a 0.45 μm filter to obtain the assay solution.

[0031] <Measurement Conditions> GPC Unit: HLC-8420GPC (manufactured by TOSOH) Columns: TSKgel Super HM-H (φ6.0mm×150mm) (two columns) Eluent: PFP / chloroform (weight ratio 35 / 65) Flow rate: 0.4 mL / min Detector: RI detector Column temperature: 40℃ Injection volume: 20μL Molecular weight standard: Standard polystyrene Equation (2) above is used to fit the molecular weight distribution curve to the sum of two normal distributions. In the fitting, the parameters (A1, A2, μ1, μ2, σ1, and σ2) in equation (2) are determined in a way that minimizes the sum of squares of the differences between the molecular weight distribution curve and the differential molecular weight distributions in each log(M) of equation (2) (the sum of normal distributions). The parameters are determined using the Solver function of Microsoft Excel under the following conditions. Furthermore, the initial values ​​of the parameters are appropriately changed in a way that minimizes the sum of squares.

[0032] <Using Software> Microsoft Excel (registered trademark) for Microsoft 365 MSO (version 2209) <Solver Conditions> • Solution: GPG nonlinearity • Convergence: 0.0001 • Differential coefficients: Central The peak position (G) is preferably 4.50 or higher, more preferably 4.60 or higher. Furthermore, the peak position (G) is preferably 4.87 or lower, more preferably 4.85 or lower.

[0033] The log(M) value of the peak of the molecular weight distribution curve is 5.05 or higher, preferably 5.06 or higher, and more preferably 5.07 or higher. Alternatively, the log(M) value of the peak of the molecular weight distribution curve may be 5.30 or lower, or 5.20 or lower. For example, the log(M) value may be 5.05 or higher and 5.30 or lower, 5.06 or higher and 5.20 or lower, or 5.07 or higher and 5.20 or lower.

[0034] Liquid crystal polyesters are any polyesters that exhibit liquid crystal properties in the molten state. A liquid crystal polyester can be a single polymer or a mixture of two or more polymers.

[0035] Liquid crystal polyesters have structural units (also called monomer units) derived from raw material monomers. The main monomer units of the liquid crystal polyester (for example, monomer units that account for 90 mol% or more, 95 mol% or more, or 99 mol% or more of all monomer units, preferably all monomer units) can be monomer units derived from aromatic compounds. Liquid crystal polyesters in which all monomer units are monomer units derived from aromatic compounds are also called fully aromatic liquid crystal polyesters.

[0036] The liquid crystal polyester comprises a first monomer unit having a fused aromatic ring and a monomer unit having a benzene ring. The liquid crystal polyester may have one or more first monomer units. Additionally, the liquid crystal polyester may have one or more second monomer units. The second monomer unit may be a monomer unit having a benzene ring but not a fused aromatic ring.

[0037] The first monomer unit may be a monomer unit from an aromatic compound (1) having a fused aromatic ring. In addition, the second monomer unit may be a monomer unit from an aromatic compound (2) having a benzene ring.

[0038] It should be noted that, in this specification, "from" refers to a situation where, in the monomer unit of the liquid crystal polyester formed by the polymerization of raw material monomers, the chemical structure of the functional groups that facilitate polymerization changes, while other structures remain unchanged. Here, "from" also includes the concept of polymerizable derivatives of the raw material monomers (e.g., compounds formed by converting the functional groups that facilitate polymerization of the raw material monomers into other polymerizable groups).

[0039] Examples of first monomer units include, for instance, monomer units derived from aromatic hydroxycarboxylic acids (1-1) having fused aromatic rings (hereinafter also referred to as monomer unit (1-1)); monomer units derived from aromatic dicarboxylic acids (1-2) having fused aromatic rings (hereinafter also referred to as monomer unit (1-2)); monomer units derived from aromatic diols (1-3) having fused aromatic rings (hereinafter also referred to as monomer unit (1-3)); and so on.

[0040] Examples of second monomer units include monomer units derived from aromatic hydroxycarboxylic acids (2-1) (hereinafter also referred to as monomer unit (2-1)), monomer units derived from aromatic dicarboxylic acids (2-2) (hereinafter also referred to as monomer unit (2-2)), monomer units derived from aromatic diols (2-3) (hereinafter also referred to as monomer unit (2-3)), etc.

[0041] The fused aromatic rings possessed by the first monomer unit can be, for example, naphthalene rings, anthracene rings, phenanthrene rings, tetraphenyl rings, pyrene rings, benzo[a]phenanthrene rings, perylene rings, fluorene rings, etc. Among these, naphthalene rings are preferred from the viewpoint of availability and price.

[0042] As monomer units in liquid crystal polyesters, examples include monomer units represented by the following formula (I) (hereinafter also referred to as monomer unit (I)), monomer units represented by the following formula (II) (hereinafter also referred to as monomer unit (II)), and monomer units represented by the following formula (III) (hereinafter also referred to as monomer unit (III)).

[0043] -O-Ar 1 -CO- (I) -CO-Ar 2 -CO- (II) -X-Ar 3 -Y- (III) [In the formula, Ar] 1 Ar 2 and Ar 3 Each independently represents a phenylene group, a biphenylene group, a fused polycyclic aromatic hydrocarbon group, or a group represented by formula (IV); Ar 1 Ar 2 and Ar 3 Some or all of the hydrogen atoms may be substituted with halogen atoms, alkyl groups, or aryl groups; X and Y each independently represent an oxygen atom or an imino group (-NH-). -Ar 4 -Z-Ar 5 - (IV) [In the formula, Ar] 4 and Ar 5 Each group independently represents a phenylene group or a fused polycyclic aromatic hydrocarbon group, and Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkyl diene. The phenylene oxide can be 1,4-phenylene oxide or 1,3-phenylene oxide, preferably 1,4-phenylene oxide.

[0044] The biphenylene oxide can be 4,4'-biphenylene oxide.

[0045] A fused polycyclic aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from a fused polycyclic aromatic hydrocarbon. Examples of fused polycyclic aromatic hydrocarbons include naphthalene, anthracene, phenanthrene, benzo[a]phenylene, pyrene, benzo[a]phenanthrene, perylene, and fluorene. Among these, naphthalene is preferred from the viewpoint of availability and price.

[0046] The fused polycyclic aromatic hydrocarbon group can be naphthylene. The naphthylene can be 2,6-naphthylene or 2,7-naphthylene, preferably 2,6-naphthylene.

[0047] Halogen atoms that can be used as substituents include fluorine, chlorine, bromine, and iodine.

[0048] The alkyl group used as a substituent can be straight-chain, branched, or cyclic. For example, the alkyl group can have 1 to 10 carbon atoms. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-hexyl, 2-ethylhexyl, n-octyl, and n-decyl.

[0049] The aryl group used as a substituent can be monocyclic or fused-ring. For example, aryl groups can have 6 to 20 carbon atoms. Examples of aryl groups include phenyl, o-tolyl, m-tolyl, p-tolyl, 1-naphthyl, and 2-naphthyl. An aryl group can be a group where the hydrogen atoms of the aromatic ring are replaced by alkyl groups, such as tolyl.

[0050] Ar 1 Ar 2 and Ar 3 The number of substituents can be, for example, 0 to 2, 0 or 1, or 0.

[0051] X and Y are preferably oxygen atoms.

[0052] The alkyl diene in Z can be straight-chain or branched. The alkyl diene can be an alkyl diene with 1 to 10 carbon atoms. Examples of alkyl dienes include methylene, ethane diene, propane diene (e.g., propane-2,2-diyl), butane diene, and octane diene (e.g., octane-3,3-diyl).

[0053] Z is preferably an oxygen atom, a sulfur atom, a methylene group, an ethanediyl group, or a propanediyl group, and more preferably an oxygen atom.

[0054] The first monomer unit can be the monomer unit (Ar) represented by equation (I). 1 It is a fused polycyclic aromatic hydrocarbon group, or Ar 4 and Ar 5 At least one of them is a group represented by formula (IV) of a fused polycyclic aromatic hydrocarbon group, or it can be a monomer unit represented by formula (II) (Ar 2 It is a fused polycyclic aromatic hydrocarbon group, or Ar 4 and Ar 5 At least one of them is a group represented by formula (IV) of a fused polycyclic aromatic hydrocarbon group, and may also be a monomer unit represented by formula (III) (Ar 2 It is a fused polycyclic aromatic hydrocarbon group, or Ar 4 and Ar 5 At least one of them is a group represented by formula (IV) of a fused polycyclic aromatic hydrocarbon group.

[0055] The first monomer unit may be a monomer unit from an aromatic compound (1) having a fused aromatic ring. Examples of aromatic compounds (1) include 2-hydroxy-6-naphthoic acid, 2,6-naphthoic acid, 2,6-dihydroxynaphthoic acid, 2-hydroxy-3-naphthoic acid, 1-hydroxy-5-naphthoic acid, 2,7-naphthodiol, etc.

[0056] The second monomer unit can be the monomer unit (Ar) represented by equation (I). 1It is phenylene, biphenylene, or Ar 4 and Ar 5 (It can be a group represented by formula (IV) of the form of phenylene), or it can be a monomer unit represented by formula (II) (Ar) 2 It is phenylene, biphenylene, or Ar 4 and Ar 5 (The group represented by formula (IV) is a phenylene group), or it can be a monomer unit represented by formula (III) (Ar) 3 It is phenylene, biphenylene, or Ar 4 and Ar 5 (The group represented by formula (IV) of the phenylene group).

[0057] The second monomer unit can be a monomer unit from an aromatic compound (2) that does not have a fused aromatic ring but has a benzene ring. Examples of aromatic compounds (2) include p-hydroxybenzoic acid, terephthalic acid, hydroquinone, isophthalic acid, 4,4'-biphenol, etc.

[0058] In liquid crystal polyesters, the content of the first monomer unit relative to the total number of monomer units constituting the liquid crystal polyester can be, for example, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, or 70 mol% or more. A higher content of the first monomer unit tends to further improve the dielectric properties. Conversely, the content of the first monomer unit relative to the total number of monomer units constituting the liquid crystal polyester can be, for example, 90 mol% or less, 85 mol% or less, or 80 mol% or less. This tends to result in better moldability and processability at low temperatures.

[0059] That is, the content of the first monomer unit relative to the total of all monomer units constituting the liquid crystal polyester can be, for example, 20 mol% or more and 90 mol% or less, 20 mol% or more and 85 mol% or less, 20 mol% or more and 80 mol% or less, 30 mol% or more and 90 mol% or less, 30 mol% or more and 85 mol% or less, 30 mol% or more and 80 mol% or less, 40 mol% or more and 40 mol% or less, 40 mol% or more and 85 mol% or less, 40 mol% or more and 80 mol% or less, 50 mol% or more and 90 mol% or less, 50 mol% or more and 85 mol% or less, 50 mol% or more and 80 mol% or less, 60 mol% or more and 90 mol% or less, 60 mol% or more and 85 mol% or more, 60 mol% or more and 80 mol% or less, 70 mol% or more and 90 mol% or more, 70 mol% or more and 85 mol% or less, or 70 mol% or more and 80 mol% or less.

[0060] In liquid crystal polyesters, the content of the second monomer unit relative to the total number of monomer units constituting the liquid crystal polyester can be, for example, 10 mol% or more, 15 mol% or more, or 20 mol% or more. This offers advantages in terms of cost. Furthermore, the content of the second monomer unit relative to the total number of monomer units constituting the liquid crystal polyester can be, for example, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, or 30 mol% or less.

[0061] That is, the content of the second monomer unit can be, for example, 10 mol% or more and 80 mol% or less, 10 mol% or more and 70 mol% or less, 10 mol% or more and 60 mol% or less, 10 mol% or more and 50 mol% or less, 10 mol% or more and 40 mol% or less, 10 mol% or more and 30 mol% or less, 15 mol% or more and 80 mol% or less, 15 mol% or more and 70 mol% or less, 15 mol% or more and 60 mol% or less, 15 mol% or more and 50 mol% or less, 15 mol% or more and 40 mol% or less, 15 mol% or more and 30 mol% or less, 20 mol% or more and 80 mol% or less, 20 mol% or more and 70 mol% or less, 20 mol% or more and 60 mol% or less, 20 mol% or more and 50 mol% or more, 20 mol% or more and 40 mol% or less, or 20 mol% or more and 30 mol% or less.

[0062] In liquid crystal polyester, the total amount of the first monomer unit and the second monomer unit relative to the total amount of all monomer units constituting the liquid crystal polyester can be, for example, 90 mol% or more, 95 mol% or more, 99 mol% or more, or 100 mol%.

[0063] Liquid crystal polyester can be a polymer having two or more monomer units (I), or it can be a polymer having monomer units (I), monomer units (II) and monomer units (III).

[0064] When the liquid crystal polyester has monomer units (I), monomer units (II), and monomer units (III), the content of monomer unit (I) relative to the total of all monomer units of the liquid crystal polyester can be, for example, 30 mol% or more, 40 mol% or more, 45 mol% or more, 50 mol% or more, or 55 mol% or more. Furthermore, when the liquid crystal polyester has monomer units (I), monomer units (II), and monomer units (III), the content of monomer unit (I) relative to the total of all monomer units of the liquid crystal polyester can be, for example, 80% or less, or 70% or less.

[0065] That is, when the liquid crystal polyester has monomer units (I), monomer units (II) and monomer units (III), the content of monomer unit (I) relative to the total of all monomer units of the liquid crystal polyester can be, for example, 30 mol% or more and 80 mol% or less, 30 mol% or more and 70 mol% or less, 40 mol% or more and 80 mol% or less, 40 mol% or more and 70 mol% or less, 45 mol% or more and 80 mol% or less, 45 mol% or more and 70 mol% or less, 50 mol% or more and 80 mol% or less, 50 mol% or more and 70 mol% or less, 55 mol% or more and 80 mol% or less, or 55 mol% or more and 70 mol% or less.

[0066] When the liquid crystal polyester has monomer units (I), monomer units (II), and monomer units (III), the content of monomer unit (II) and the content of monomer unit (III) relative to the total of all monomer units of the liquid crystal polyester can be, for example, 35 mol% or less, or 30 mol% or less. Furthermore, when the liquid crystal polyester has monomer units (I), monomer units (II), and monomer units (III), the content of monomer unit (II) and the content of monomer unit (III) relative to the total of all monomer units of the liquid crystal polyester can be, for example, 5 mol% or more, 10 mol% or more, or 15 mol% or more.

[0067] That is, when the liquid crystal polyester has monomer units (I), monomer units (II) and monomer units (III), the content of monomer unit (II) and the content of monomer unit (III) relative to the total of all monomer units of the liquid crystal polyester can be, for example, 5 mol% or more and 35 mol% or less, 5 mol% or more and 30 mol% or less, 10 mol% or more and 35 mol% or less, 10 mol% or more and 30 mol% or less, 15 mol% or more and 35 mol% or less, or 15 mol% or more and 30 mol% or less.

[0068] The liquid crystal polyester may have monomer units other than monomer units (I), monomer units (II) and monomer units (III), and the number of monomer units other than monomer units (I) and monomer units (III) may be less than 10 mol%, less than 5 mol%, less than 2 mol%, less than 1 mol%, or less than 0 mol% relative to the total number of monomer units of the liquid crystal polyester.

[0069] In this specification, the number of each monomer unit in the liquid crystal polyester is determined by the analytical method described in Japanese Patent Application Publication No. 2000-19168. Specifically, the liquid crystal polyester is depolymerized by reacting it with a lower alcohol in a supercritical state, and the depolymerization products (monomers from which each monomer unit is derived) are quantified by liquid chromatography, thereby calculating the number of each monomer unit relative to the total number of monomer units.

[0070] Liquid crystal polyesters can be manufactured by polymerizing raw material monomers corresponding to the monomer units constituting them. For example, they can be manufactured according to the method described in Japanese Patent No. 6439027.

[0071] The dielectric loss tangent of the liquid crystal polyester at 10 GHz can be, for example, 0.002 or less, preferably 0.0015 or less, and more preferably 0.001 or less. The dielectric loss tangent of the liquid crystal polyester at 10 GHz can be, for example, greater than or equal to 0.0001 and less than 0.002, greater than or equal to 0.0001 and less than 0.0015, or greater than or equal to 0.0001 and less than 0.001.

[0072] The relative permittivity of the liquid crystal polyester at 10 GHz can be, for example, 4.0 or less, or 3.8 or less. Alternatively, the relative permittivity of the liquid crystal polyester at 10 GHz can be, for example, 2.8 or more, or 3.0 or more. The relative permittivity of the liquid crystal polyester at 10 GHz can be, for example, 2.8 or more and 4.0 or less, or 3.0 or more and 3.8 or less.

[0073] In this specification, the dielectric loss tangent and relative permittivity of the liquid crystal polyester at 10 GHz are determined by the following method.

[0074] Using an injection molding machine (FANUC ROBOSHOT S-2000i 30B), liquid crystal polyester granules were used as the molding material at a mold temperature of 130°C and an injection speed of 50 mm / s to obtain test pieces with a width of 50 mm, a length of 50 mm, and a thickness of 0.5 mm. The barrel temperature was set to the temperature at which the liquid crystal polyester melts and can flow into the mold (e.g., 300~350°C). For the obtained test pieces, the relative permittivity and dielectric loss tangent at 10 GHz were measured using a vector network analyzer (Keysight Technologies N5290A) and a split cylindrical resonator (EM labs CR710). The measurement environment was set at 23°C and 50% RH.

[0075] The flow initiation temperature of the liquid crystal polyester can be, for example, above 250°C or above 270°C. Alternatively, the flow initiation temperature of the liquid crystal polyester can be, for example, below 400°C, below 360°C, or below 340°C.

[0076] That is, the flow start temperature of the liquid crystal polyester can be, for example, above 250°C and below 400°C, above 250°C and below 360°C, above 250°C and below 340°C, above 270°C and below 400°C, above 270°C and below 360°C, or above 270°C and below 340°C.

[0077] In this specification, the flow initiation temperature of the liquid crystal polyester was determined using a flow tester at 9.8 MPa (100 kg / cm²). 2 Under a load of ), the liquid crystal polyester was melted while heating at a rate of 4°C / min, and the molten liquid crystal polyester was extruded from a nozzle with an inner diameter of 1 mm and a length of 10 mm. The viscosity of the molten liquid crystal polyester was 4800 Pa•s (48000 poise).

[0078] The number-average molecular weight (Mn) of liquid crystal polyester can be, for example, 35,000 or more, and from the viewpoint of superior mechanical properties and heat resistance, it can be 37,000 or more, 39,000 or more, or 40,000 or more. Alternatively, the number-average molecular weight (Mn) of liquid crystal polyester can be, for example, 60,000 or less, and from the viewpoint of superior flowability and softness, it can be 58,000 or less, 56,000 or less, or 55,000 or less. The number-average molecular weight (Mn) of liquid crystal polyester can be, for example, 35,000 or more and 60,000 or less, 37,000 or more and 58,000 or less, 39,000 or more and 56,000 or less, or 40,000 or more and 55,000 or less.

[0079] The weight-average molecular weight (Mw) of liquid crystal polyester can be, for example, 100,000 or more, and from the viewpoint of superior mechanical properties and heat resistance, it can be 120,000 or more, 130,000 or more, or 140,000 or more. Alternatively, the weight-average molecular weight (Mw) of liquid crystal polyester can be, for example, 250,000 or less, and from the viewpoint of superior flowability and softness, it can be 230,000 or less, 220,000 or less, or 210,000 or less. The weight-average molecular weight (Mw) of liquid crystal polyester can be, for example, 100,000 or more and 250,000 or less, 120,000 or more and 230,000 or less, 130,000 or more and 220,000 or less, or 140,000 or more and 210,000 or less.

[0080] The ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) of the liquid crystal polyester (Mw / Mn) can be, for example, 3.20 or higher, and from the viewpoint of superior heat resistance, it can be 3.25 or higher, 3.30 or higher, or 3.35 or higher. Furthermore, the above ratio (Mw / Mn) can be, for example, 3.96 or lower, and from the viewpoint of superior flowability, it can be 3.95 or lower, 3.94 or lower, or 3.93 or lower. The ratio (Mw / Mn) can be, for example, 3.20 or higher and 3.96 or lower, 3.25 or higher and 3.95 or lower, 3.30 or higher and 3.94 or lower, or 3.35 or higher and 3.93 or lower.

[0081] In this specification, the number-average molecular weight (Mn), weight-average molecular weight (Mw), and ratio (Mw / Mn) of the liquid crystal polyester are values ​​obtained from the above molecular weight distribution curve.

[0082] Liquid crystal polyester can be a single liquid crystal polyester or a mixture of two or more liquid crystal polyesters. For example, liquid crystal polyester can be a mixture of two or more liquid crystal polyesters with different molecular weights.

[0083] The liquid crystal polyester may, for example, comprise a first liquid crystal polyester having a first molecular weight distribution curve and a second liquid crystal polyester having a second molecular weight distribution curve. In this case, the log(M) value of the peak of the first molecular weight distribution curve may be less than the log(M) value of the peak of the second molecular weight distribution curve. Furthermore, the content of the first liquid crystal polyester may be less than the content of the second liquid crystal polyester.

[0084] Liquid crystal polyesters exhibit good flowability when melted and produce molded articles with excellent mechanical properties. Therefore, liquid crystal polyesters are suitable as molding materials for obtaining molded articles. Liquid crystal polyesters can be used, for example, in granular form.

[0085] Liquid crystal polyester can be mixed with other components to be used as a liquid crystal polyester composition.

[0086] The liquid crystal polyester composition may, for example, contain one or more resins other than liquid crystal polyesters. Examples of such resins include polyolefins, cyclic polyolefins, polyvinyl chloride, polysulfone, (meth)acrylic resins, polyphenylene ether resins, polyacetal resins, polyamide resins, imide resins, cellulose resins, polyether ether ketone resins, fluororesins, polycarbonate resins, styrene-based resins, thermosetting resins, etc.

[0087] In addition, the liquid crystal polyester composition may further include inorganic fillers, colorants, dispersants, plasticizers, antioxidants, curing agents, flame retardants, heat stabilizers, ultraviolet absorbers, antistatic agents, surfactants, lubricants, release agents, etc.

[0088] Liquid crystal polyester compositions are suitable for use as molding materials due to their excellent melt flowability. For example, liquid crystal polyester compositions can be used in granular form.

[0089] The molded articles of this embodiment can be molded articles comprising the above-described liquid crystal polyester, or molded articles comprising the above-described liquid crystal polyester composition. The molded articles of this embodiment can be connectors, sockets, relay components, coil frames, optical pickups, oscillators, semiconductor packages, IC trays, wafer carriers, components for household appliances, lighting fixtures, audio equipment, optical cable clamps, telephone components, fax components, modem components, release claws, heater brackets, impellers, fan gears, gears, bearings, motor components, motor housings, engine components, engine compartment components, electrical components, automotive interior trim components, microwave cooking pots, heat-resistant tableware, flooring materials, wall materials, beams, columns, roofing materials, aircraft components, spacecraft components, aerospace equipment components, nuclear reactors, marine facility components, washing fixtures, optical equipment components, valves, pipes, nozzles, filters, membranes, medical equipment components, medical materials, sensor components, sanitary spare parts, sporting goods, or leisure goods.

[0090] The molded article of this embodiment can be obtained, for example, by molding the above-described liquid crystal polyester or liquid crystal polyester composition into the desired shape and performing processing as needed.

[0091] As a molding method for molded products, melt molding is preferred. Examples of melt molding methods include injection molding, extrusion molding, compression molding, blow molding, vacuum molding, foam molding, and compression molding.

[0092] The above describes suitable embodiments of the present disclosure, but the present disclosure is not limited to the above embodiments.

[0093] Example The following examples illustrate the invention disclosed herein in more detail, but the invention disclosed herein is not limited to these examples. Hereinafter, unless otherwise specified, percentages and parts of content or usage are used on a mass basis.

[0094] (Manufacturing Example 1) Manufacturing of Liquid Crystal Polyester (LCP1) In a reactor equipped with a stirrer, torque meter, nitrogen inlet pipe, thermometer, and reflux cooler, 1035.0 g (5.5 mol) of 2-hydroxy-6-naphthoic acid, 378.3 g (1.75 mol) of 2,6-naphthoic acid, 83.1 g (0.5 mol) of terephthalic acid, 255.2 g of hydroquinone, 1226.87 g (12 mol) of acetic anhydride, and 0.17 g of 1-methylimidazole as a catalyst were added. After the reactor was fully purged with nitrogen, the temperature was raised to 140°C over a nitrogen flow for 30 minutes and maintained at that temperature while refluxing for 1 hour.

[0095] Then, while removing the distilled byproduct acetic acid by distillation, the temperature was increased to 310°C over 4 hours and 35 minutes. The reaction was considered complete when the torque increased, and the contents were removed. The flow onset temperature of the obtained solid component was 270°C. The obtained solid component was cooled to room temperature, pulverized using a coarse pulverizer, and then heated from room temperature to 250°C over 1 hour under a nitrogen atmosphere, followed by a further increase from 250°C to 280°C over 5 hours. The temperature was then maintained at 280°C for 6 hours to carry out the polymerization reaction in the solid phase. The flow onset temperature of the obtained liquid crystal polyester (LCP1) was 301°C.

[0096] <Determination of Flow Onset Temperature> Using a flow testing apparatus (Shimadzu Corporation, CFT-500 model), approximately 2g of liquid crystal polyester granules were filled into a barrel equipped with a nozzle having an inner diameter of 1mm and a length of 10mm, and tested at 9.8MPa (100kg / cm²). 2 Under a load of 4°C / min, the liquid crystal polyester was melted and extruded from a nozzle. The temperature (FT) at which the viscosity was measured to be 4800 Pa•s (48000 P) was taken as the flow initiation temperature. "Approximately 2g" can be estimated as 2g ± 0.1g.

[0097] The relative permittivity of liquid crystal polyester (LCP1) at 10 GHz is 3.5, and the dielectric loss tangent is 0.0010. Additionally, the barrel temperature during test piece fabrication was set to 320°C.

[0098] (Manufacturing Example 2) Manufacturing of Liquid Crystal Polyester (LCP2) In a reactor equipped with a stirrer, torque meter, nitrogen inlet pipe, thermometer, and reflux cooler, 1035.0 g (5.5 mol) of 2-hydroxy-6-naphthoic acid, 378.3 g (1.75 mol) of 2,6-naphthoic acid, 83.1 g (0.5 mol) of terephthalic acid, 255.2 g of hydroquinone, 1226.87 g (12 mol) of acetic anhydride, and 0.17 g of 1-methylimidazole as a catalyst were added. After the reactor was fully purged with nitrogen, the temperature was raised to 140°C over a nitrogen flow for 30 minutes and maintained at that temperature while refluxing for 1 hour.

[0099] Then, while removing the distilled byproduct acetic acid by distillation, the temperature was increased to 310°C over 4 hours and 35 minutes. The reaction was considered complete when the torque increased, and the contents were removed. The flow onset temperature of the obtained solid component was 264°C. The obtained solid component was cooled to room temperature, pulverized using a coarse pulverizer, and then heated from room temperature to 250°C over 1 hour under a nitrogen atmosphere, followed by a further increase from 250°C to 292°C over 7 hours. The temperature was then maintained at 292°C for 6 hours to carry out the polymerization reaction in the solid phase. The flow onset temperature of the obtained liquid crystal polyester (LCP2) was 319°C.

[0100] The relative permittivity of liquid crystal polyester (LCP2) at 10 GHz is 3.6, and the dielectric loss tangent is 0.00091. Additionally, the barrel temperature during test piece fabrication was set to 320°C.

[0101] (Manufacturing Example 3) Manufacturing of Liquid Crystal Polyester (LCP3) In a reactor equipped with a stirrer, torque meter, nitrogen inlet pipe, thermometer, and reflux cooler, 1035.0 g (5.5 mol) of 2-hydroxy-6-naphthoic acid, 378.3 g (1.75 mol) of 2,6-naphthoic acid, 83.1 g (0.5 mol) of terephthalic acid, 255.2 g of hydroquinone, 1226.87 g (12 mol) of acetic anhydride, and 0.17 g of 1-methylimidazole as a catalyst were added. After the reactor was fully purged with nitrogen, the temperature was raised to 140°C over a nitrogen flow for 30 minutes and maintained at that temperature while refluxing for 1 hour.

[0102] Then, while removing the distilled byproduct acetic acid by distillation, the temperature was increased to 310°C over 4 hours and 35 minutes. The reaction was considered complete when the torque increased, and the contents were removed. The flow start temperature of the obtained solid component was 270°C. The obtained solid component was cooled to room temperature, pulverized with a coarse pulverizer, and then heated from room temperature to 250°C over 1 hour under a nitrogen atmosphere, followed by a further increase from 250°C to 306°C over 9 hours and 20 minutes. The temperature was maintained at 306°C for 6 hours to carry out the polymerization reaction in the solid phase. The flow start temperature of the obtained liquid crystal polyester (LCP3) was 330°C.

[0103] The relative permittivity of liquid crystal polyester (LCP3) at 10 GHz is 3.6, and the dielectric loss tangent is 0.00061. Additionally, the barrel temperature during test piece fabrication was set to 340℃.

[0104] (Manufacturing Example 4) Manufacturing of Liquid Crystal Polyester (LCP4) In a reactor equipped with a stirrer, torque meter, nitrogen inlet pipe, thermometer, and reflux cooler, 1511.1 g (8.03 mol) of 2-hydroxy-6-naphthoic acid, 410.2 g (2.97 mol) of p-hydroxybenzoic acid, 1291.4 g (12.65 mol) of acetic anhydride, and 0.058 g of 1-methylimidazole as a catalyst were added. After the reactor was fully purged with nitrogen, the temperature was raised to 140°C over a nitrogen flow for 30 minutes and then maintained under reflux for 1 hour.

[0105] Then, while removing the distilled byproduct acetic acid by distillation, the temperature was raised to 275°C over 4 hours. The reaction was considered complete when the torque increased, and the contents were removed. The flow onset temperature of the obtained solid component was 217°C. The obtained solid component was cooled to room temperature, pulverized using a coarse pulverizer, and then heated from room temperature to 200°C over 1 hour under a nitrogen atmosphere, followed by a further heating from 200°C to 242°C over 7 hours. The temperature was maintained at 242°C for 10 hours to carry out the polymerization reaction in the solid phase. The flow onset temperature of the obtained liquid crystal polyester (LCP4) was 292°C.

[0106] The relative permittivity of liquid crystal polyester (LCP4) at 10 GHz is 3.5, and the dielectric loss tangent is 0.0011. Additionally, the barrel temperature during test piece fabrication was set to 310°C.

[0107] (Manufacturing Example 5) Manufacturing of Liquid Crystal Polyester (LCP5) In a reactor equipped with a stirrer, torque meter, nitrogen inlet pipe, thermometer, and reflux cooler, 1511.1 g (8.03 mol) of 2-hydroxy-6-naphthoic acid, 410.2 g (2.97 mol) of p-hydroxybenzoic acid, 1291.4 g (12.65 mol) of acetic anhydride, and 0.058 g of 1-methylimidazole as a catalyst were added. After the reactor was fully purged with nitrogen, the temperature was raised to 140°C over a nitrogen flow for 30 minutes and then maintained under reflux for 1 hour.

[0108] Then, while removing the distilled byproduct acetic acid by distillation, the temperature was raised to 275°C over 4 hours. The reaction was considered complete when the torque increased, and the contents were removed. The flow start temperature of the obtained solid component was 217°C. The obtained solid component was cooled to room temperature, pulverized using a coarse pulverizer, and then heated from room temperature to 200°C over 1 hour under a nitrogen atmosphere, followed by a further increase from 200°C to 247°C over 7 hours and 50 minutes. The mixture was then held at 247°C for 10 hours to carry out the polymerization reaction in the solid phase. The flow start temperature of the obtained liquid crystal polyester (LCP5) was 298°C.

[0109] The relative permittivity of liquid crystal polyester (LCP5) at 10 GHz is 3.5, and the dielectric loss tangent is 0.0011. Additionally, the barrel temperature during test piece fabrication was set to 330°C.

[0110] (Manufacturing Example 6) Manufacturing of Liquid Crystal Polyester (LCP6) In a reactor equipped with a stirrer, torque meter, nitrogen inlet pipe, thermometer, and reflux cooler, 1511.1 g (8.03 mol) of 2-hydroxy-6-naphthoic acid, 410.2 g (2.97 mol) of p-hydroxybenzoic acid, 1291.4 g (12.65 mol) of acetic anhydride, and 0.058 g of 1-methylimidazole as a catalyst were added. After the reactor was fully purged with nitrogen, the temperature was raised to 140°C over a nitrogen flow for 30 minutes and then maintained under reflux for 1 hour.

[0111] Then, while removing the distilled byproduct acetic acid by distillation, the temperature was raised to 275°C over 4 hours. The reaction was considered complete when the torque increased, and the contents were removed. The flow onset temperature of the obtained solid component was 217°C. The obtained solid component was cooled to room temperature, pulverized using a coarse pulverizer, and then heated from room temperature to 200°C over 1 hour under a nitrogen atmosphere, followed by a further increase from 200°C to 259°C over 9 hours and 50 minutes. The temperature was maintained at 259°C for 10 hours to carry out the polymerization reaction in the solid phase. The flow onset temperature of the obtained liquid crystal polyester (LCP6) was 312°C.

[0112] The relative permittivity of liquid crystal polyester (LCP6) at 10 GHz is 3.6, and the dielectric loss tangent is 0.0010. Additionally, the barrel temperature during test piece fabrication was set to 345℃.

[0113] (Example 1) (1) Manufacturing of liquid crystal polyester and granules Liquid crystal polyester (LCP1) and liquid crystal polyester (LCP5) were mixed at a mass ratio of 60:40 to obtain the liquid crystal polyester of Example 1. Next, the liquid crystal polyester was granulated using a twin-screw extruder (manufactured by Ikegai Iron Works Co., Ltd., PCM-30) at a barrel temperature of 320°C to obtain liquid crystal polyester granules.

[0114] (2) Evaluation of liquid crystal polyester and molded products The number-average molecular weight (Mn) of the obtained liquid crystal polyester was 43,500, the weight-average molecular weight (Mw) was 147,000, and the ratio (Mw / Mn) was 3.38. Furthermore, the molecular weight distribution curve of the liquid crystal polyester is shown in Table 1, with the peak position at log(M) = 5.07. Additionally, the molecular weight distribution curve of the liquid crystal polyester was fitted using the above equation (2), and the results showed A1 = 32.3, μ1 = 4.61, and σ1 = 32.3. 2 =0.247, A2 is 63.4, μ2 is 5.13, σ2 2 The value is 0.133, and the peak position (G) is 4.78.

[0115] The melt viscosity, tensile strength, nominal strain at tensile fracture, relative permittivity, dielectric loss tangent, and load deflection temperature were determined using the following method. The results are shown in Table 1.

[0116] <Evaluation of fluidity at melt> Using a capillary rheometer (Toyo Seiki Co., Ltd., Capilograph 1D), a capillary tube with an inner diameter of 0.5 mm and a length of 10 mm was installed at the front end of the barrel. Liquid crystal polyester granules were melted in the barrel heated to 340°C and extruded from the nozzle. The viscosity of the extruded liquid crystal polyester was measured at a shear rate of 1000 rpm, and this viscosity was used as the melt viscosity of the liquid crystal polyester for evaluation.

[0117] <Determination of Tensile Strength and Nominal Strain at Tensile Break> Using an injection molding machine (Nissei Resin Kogyo Co., Ltd., PNX-40-5A), liquid crystal polyester granules were used as the molding material to injection mold ASTM D638 dumbbell-shaped test pieces IV (2.5 mm thick) under the conditions of barrel temperature 330°C, mold temperature 130°C, and injection speed 75 mm / s. Five dumbbell test pieces were then subjected to tensile testing using a tensile testing machine (A&D Corporation, TENSILON RTG-1310) at a chuck distance of 50 mm, crosshead speed of 10 mm / min, and test temperature of 25°C. The elongation was measured, and the tensile strength at fracture (MPa) and nominal strain at fracture (%) were calculated as the average values ​​of the five samples.

[0118] It should be noted that the nominal strain at tensile fracture is calculated using the following formula.

[0119] Nominal strain at tensile fracture (%) = (L - Lo) / Lo × 100 Lo: Length of the distance between the chucks before the test (mm) L: The length of the distance between the chucks at the time of fracture (mm) Evaluation of dielectric properties Using an injection molding machine (FANUC, ROBOSHOT S-2000i 30B), liquid crystal polyester granules were used as molding materials at a barrel temperature of 325°C, a mold temperature of 130°C, and an injection speed of 50 mm / s to obtain test pieces with a width of 50 mm, a length of 50 mm, and a thickness of 0.5 mm. For the obtained test pieces, the relative permittivity and dielectric loss tangent at 10 GHz were measured using a vector network analyzer (Keysight Technologies, N5290A) and a split cylindrical resonator (EM labs, CR710).

[0120] • Test environment: 23℃, 50%RH <Evaluation of Load-Bend Temperature> Using an injection molding machine (Nissei Resin Kogyo Co., Ltd., PNX-40-5A), rod-shaped molded bodies were produced according to ASTM D648 by using liquid crystal polyester granules as the molding material under the conditions of barrel temperature 330°C, mold temperature 130°C, and injection speed 75 mm / s. The load flexural temperature (DTUL (°C)) of the rod-shaped molded bodies was measured according to ASTM D648 with a load of 1.82 MPa and a heating rate of 2°C / min.

[0121] (Example 2) Liquid crystal polyester (LCP1), liquid crystal polyester (LCP3), and liquid crystal polyester (LCP5) were mixed at a mass ratio of 50:10:40 to obtain the liquid crystal polyester of Example 2. Using the obtained liquid crystal polyester, granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 1.

[0122] It should be noted that in Example 2, the barrel temperature during granulation is set to 320°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> is set to 330°C, the barrel temperature in <Evaluation of Dielectric Properties> is set to 325°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> is set to 330°C.

[0123] (Example 3) Liquid crystal polyester (LCP1) and liquid crystal polyester (LCP6) were mixed at a mass ratio of 60:40 to obtain the liquid crystal polyester of Example 3. Using the obtained liquid crystal polyester, granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 1.

[0124] It should be noted that in Example 3, the barrel temperature during granulation was set to 325°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> was set to 330°C, the barrel temperature in <Evaluation of Dielectric Properties> was set to 325°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> was set to 330°C.

[0125] (Example 4) Liquid crystal polyester (LCP1) and liquid crystal polyester (LCP6) were mixed at a mass ratio of 80:20 to obtain the liquid crystal polyester of Example 4. Using the obtained liquid crystal polyester, granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 1.

[0126] It should be noted that in Example 4, the barrel temperature during granulation was set to 325°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> was set to 330°C, the barrel temperature in <Evaluation of Dielectric Properties> was set to 325°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> was set to 330°C.

[0127] (Comparative Example 1) Liquid crystal polyester (LCP2) and liquid crystal polyester (LCP4) were mixed at a mass ratio of 60:40 to obtain the liquid crystal polyester of Comparative Example 1. Using the obtained liquid crystal polyester, granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 2.

[0128] In addition, in Comparative Example 1, the barrel temperature during granulation was set to 320°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> was set to 340°C, the barrel temperature in <Evaluation of Dielectric Properties> was set to 330°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> was set to 340°C.

[0129] (Comparative Example 2) Liquid crystal polyester (LCP1) and liquid crystal polyester (LCP5) were mixed at a mass ratio of 80:20 to obtain the liquid crystal polyester of Comparative Example 2. Using the obtained liquid crystal polyester, granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 2.

[0130] In addition, in Comparative Example 2, the barrel temperature during granulation was set to 320°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> was set to 320°C, the barrel temperature in <Evaluation of Dielectric Properties> was set to 330°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> was set to 320°C.

[0131] (Comparative Example 3) Using only liquid crystal polyester (LCP1), granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 2.

[0132] In addition, in Comparative Example 3, the barrel temperature during granulation was set to 320°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> was set to 330°C, the barrel temperature in <Evaluation of Dielectric Properties> was set to 320°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> was set to 330°C.

[0133] (Comparative Example 4) Liquid crystal polyester (LCP3) and liquid crystal polyester (LCP5) were mixed at a mass ratio of 60:40 to obtain the liquid crystal polyester of Comparative Example 4. Using the obtained liquid crystal polyester, granules were prepared, and the liquid crystal polyester and molded articles were evaluated using the same method as in Example 1. The results are shown in Table 2.

[0134] In addition, in Comparative Example 4, the barrel temperature during granulation was set to 340°C, the barrel temperature in <Determination of Tensile Strength and Nominal Strain at Tensile Break> was set to 330°C, the barrel temperature in <Evaluation of Dielectric Properties> was set to 330°C, and the barrel temperature in <Evaluation of Load Deflection Temperature> was set to 330°C.

[0135] Figure 1 This is a graph showing the molecular weight distribution curve of Example 1. Figure 1 In the diagram, 10 represents the molecular weight distribution curve, and 1, 2, and 3 represent the first normal distribution, the second normal distribution, and their sum. In the above fitting, the molecular weight distribution curve 10 is fitted as the sum of the first normal distribution 1 and the second normal distribution 2.

Claims

1. A liquid crystal polyester, wherein the peak position (G) calculated by formula (1) is above 4.50 and below 4.

87. The peak of the molecular weight distribution curve, expressed as log(M), is above 5.

05. [Mathematical Expression 1] In equation (1), A1, A2, μ1, and μ2 represent the values ​​of the molecular weight distribution curve (vertical axis: differential molecular weight distribution, horizontal axis: logarithm of the molecular weight converted from polystyrene with a base of 10) obtained by GPC, respectively, when fitted with equation (2) with μ1 < μ2. [Mathematical Expression 2] In equation (2), M represents the molecular weight, and log(M) represents the logarithm of the molecular weight.

2. The liquid crystal polyester according to claim 1, wherein, The peak in the molecular weight distribution curve is above 5.05 and below 5.30, expressed in log(M).

3. The liquid crystal polyester according to claim 1, wherein, A1 < A2.

4. The liquid crystal polyester according to claim 1, wherein, The weight-average molecular weight (Mw) is above 100,000 and below 250,000.

5. The liquid crystal polyester according to claim 1, wherein, The number-average molecular weight (Mn) is above 35,000 and below 60,000.

6. The liquid crystal polyester according to claim 1, wherein, The ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) (Mw / Mn) is greater than 3.20 and less than 3.

96.

7. The liquid crystal polyester according to claim 1, comprising a first monomer unit having a fused aromatic ring and a second monomer unit having a benzene ring.

8. The liquid crystal polyester according to claim 7, wherein, The fused aromatic ring is a naphthalene ring.

9. The liquid crystal polyester according to claim 1, wherein it comprises two or more liquid crystal polyesters.

10. The liquid crystal polyester according to claim 1, comprising: The first liquid crystal polyester with the first molecular weight distribution curve, and The second liquid crystal polyester having a second molecular weight distribution curve The log(M) value of the peak of the first molecular weight distribution curve is less than the log(M) value of the peak of the second molecular weight distribution curve.

11. A method for manufacturing a liquid crystal polyester, comprising the method for manufacturing the liquid crystal polyester according to any one of claims 1 to 10, wherein, This includes a process of mixing two or more liquid crystal polyesters.

12. The manufacturing method according to claim 11, wherein, The process described is the mixing of a first liquid crystal polyester having a first molecular weight distribution curve and a second liquid crystal polyester having a second molecular weight distribution curve. The log(M) value of the peak of the first molecular weight distribution curve is less than the log(M) value of the peak of the second molecular weight distribution curve.

13. A granule comprising the liquid crystal polyester according to any one of claims 1 to 10.

14. A molded article comprising the liquid crystal polyester according to any one of claims 1 to 10, The molded products include connectors, sockets, relay components, coil frames, optical pickups, oscillators, semiconductor packages, IC trays, wafer carriers, components for household appliances, lighting fixtures, audio equipment, fiber optic cable clamps, telephone components, fax components, modem components, release claws, heater brackets, impellers, fan gears, gears, bearings, motor components, motor housings, engine components, engine compartment components, electrical components, automotive interior trim components, microwave cooking pots, heat-resistant tableware, flooring materials, wall materials, beams, columns, roofing materials, aircraft components, spacecraft components, aerospace equipment components, nuclear reactors, marine facility components, washing fixtures, optical equipment components, valves, pipes, nozzles, filters, membranes, medical equipment components, medical materials, sensor components, sanitary spare parts, and sporting or leisure products.

Images