WO2024166655A1 - Resin composition, molded article, and film - Google Patents

Abstract

The present invention relates to: a resin composition which comprises a liquid-crystal polyester and an aromatic polysulfone, in which the liquid-crystal polyester has a repeating unit (i) represented by formula (I), the aromatic polysulfone has one or more functional groups (fg) selected from the group consisting of a hydroxy group and an amino group, and the total content of the functional groups (fg) in the aromatic polysulfone is 10 μmol/g or more; and others.

Description

Resin composition, molded article and film

The present invention relates to a resin composition, a molded article, and a film.
This application claims priority based on Japanese Patent Application No. 2023-016127, filed on February 6, 2023, the contents of which are incorporated herein by reference.

Liquid crystal polyester is known to have high chemical stability, heat resistance and dimensional accuracy, and is used in a variety of fields, including electrical, electronic, mechanical, optical equipment, automotive, aircraft and medical fields. Among these fields, liquid crystal polyester is attracting attention as a material for electronic components, in particular, due to its high frequency characteristics and low water absorption.

Compared to other thermoplastic resins, liquid crystal polyester has a superior dielectric tangent at high frequencies. In addition, liquid crystal polyester has high heat resistance, so its relative dielectric constant and dielectric tangent are thermally stable. In addition, liquid crystal polyester has low water absorption, so there is almost no change in the relative dielectric constant and dielectric tangent due to water absorption.

For example, Patent Document 1 discloses an aromatic liquid crystal polyester having four specific repeating structural units in a specified ratio. The aromatic liquid crystal polyester disclosed in Patent Document 1 is said to have an excellent balance between heat resistance and film processability, and to be useful for preparing films with low dielectric loss.

JP 2005-272810 A

However, when the liquid crystal polyester is used as a molding material, anisotropy becomes a problem.
When a conventional molding material containing liquid crystal polyester is used, the liquid crystal polyester is easily oriented in the flow direction (MD), which may cause a difference in the properties of the molded product between the MD and the direction perpendicular to the MD (TD), resulting in poor manufacturing processability of electronic parts.

The present invention was made in consideration of these circumstances, and aims to provide a resin composition that contains liquid crystal polyester and has reduced anisotropy, as well as molded articles and films made from this resin composition.

To solve the above problems, the present invention includes the following aspects.

[1] A resin composition comprising a liquid crystal polyester and an aromatic polysulfone, the liquid crystal polyester having a repeating unit (i) represented by the following formula (I), the aromatic polysulfone having at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group, and the total amount of the functional groups (fg) possessed by the aromatic polysulfone being 10 μmol/g or more.

［式（Ｉ）中、ナフチレン基にある水素原子の一部又は全部は、ハロゲン原子、アルキル基、アルコキシ基又はアリール基で置換されていてもよい。］

[In formula (I), some or all of the hydrogen atoms in the naphthylene group may be substituted with a halogen atom, an alkyl group, an alkoxy group or an aryl group.]

[2] The resin composition according to [1], wherein the number of repeating units (i) contained in the liquid crystal polyester is 40 mol% or more relative to the total number (100 mol%) of all repeating units constituting the liquid crystal polyester.

[3] The resin composition according to [1] or [2], wherein the content of the aromatic polysulfone is 0.1 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the total content of the liquid crystal polyester and the aromatic polysulfone.

[4] A molded article comprising the resin composition according to any one of [1] to [3].
[5] A film comprising the resin composition according to any one of [1] to [3].

The present invention provides a resin composition that contains liquid crystal polyester and has reduced anisotropy, as well as a molded article and film molded from this resin composition.

FIG. 1 is a cross-sectional view showing one embodiment of a film.

(Resin composition)
One embodiment of the resin composition contains a liquid crystal polyester and an aromatic polysulfone. The liquid crystal polyester in the resin composition of this embodiment has a repeating unit (i) represented by formula (I). The aromatic polysulfone in the resin composition of this embodiment has at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group, and the total amount of the functional groups (fg) of the aromatic polysulfone is 10 μmol/g or more. The resin composition of this embodiment is particularly suitable as a molding material for electronic parts, and has a reduced anisotropy.

<Liquid crystal polyester>
The liquid crystal polyester contained in the resin composition of the present embodiment has a repeating unit (i) represented by the following formula (I). Such liquid crystal polyester includes a liquid crystal polyester obtained by polymerizing an acylation product obtained by acylation of at least hydroxynaphthoic acid and a fatty acid anhydride.

［式（Ｉ）中、ナフチレン基にある水素原子の一部又は全部は、ハロゲン原子、アルキル基、アルコキシ基又はアリール基で置換されていてもよい。］

[In formula (I), some or all of the hydrogen atoms in the naphthylene group may be substituted with a halogen atom, an alkyl group, an alkoxy group or an aryl group.]

The repeating unit (i) represented by the formula (I) is preferably a repeating unit derived from 6-hydroxy-2-naphthoic acid or a compound in which the phenolic hydroxyl group of 6-hydroxy-2-naphthoic acid is acylated.

In this specification, "derived from" means that the chemical structure of the functional group that contributes to the polymerization changes as the raw material monomer polymerizes, and no other structural changes occur.

In the formula (I), examples of the halogen atom which can substitute for a hydrogen atom in the naphthylene group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
In the formula (I), the alkyl group capable of substituting a hydrogen atom in the naphthylene group is preferably an alkyl group having 1 to 10 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, an n-heptyl group, a 2-ethylhexyl group, an n-octyl group, an n-nonyl group, and an n-decyl group.
In the formula (I), the alkoxy group capable of substituting a hydrogen atom in the naphthylene group is preferably an alkoxy group having 1 to 6 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a tert-butoxy group, a hexyloxy group, and a cyclohexyloxy group.
In the formula (I), the aryl group capable of substituting a hydrogen atom in the naphthylene group is preferably an aryl group having 6 to 20 carbon atoms, and examples of such aryl groups include monocyclic aromatic groups such as a phenyl group, an o-tolyl group, an m-tolyl group, and a p-tolyl group; and condensed aromatic groups such as a 1-naphthyl group, and a 2-naphthyl group.

When a hydrogen atom in the naphthylene group is substituted with a halogen atom, an alkyl group, an alkoxy group or an aryl group, the number of substitutions per naphthylene group is preferably 1 or 2, and more preferably 1.
In the liquid crystal polyester contained in the resin composition of the present embodiment, the naphthylene group in the repeating unit (i) represented by the formula (I) is preferably not substituted.

The number of the repeating units (i) contained in the liquid crystal polyester contained in the resin composition of this embodiment is preferably 40 mol% or more, more preferably 45 mol% or more, and even more preferably 50 mol% or more, relative to the total number (100 mol%) of all repeating units constituting the liquid crystal polyester.
The number of the repeating units (i) is preferably 90 mol % or less, more preferably 85 mol % or less, and even more preferably 80 mol % or less, based on the total number (100 mol %) of all repeating units constituting the liquid crystal polyester.

When the number of repeating units (i) in the liquid crystal polyester is within the above-mentioned preferred range, the effect of mitigating the anisotropy of the liquid crystal polyester is easily achieved. In addition, the dielectric tangent of the molded product is reduced.

For example, the number of repeating units (i) contained in the liquid crystal polyester is preferably 40 mol% or more and 90 mol% or less, more preferably 45 mol% or more and 85 mol% or less, and even more preferably 50 mol% or more and 80 mol% or less, relative to the total number (100 mol%) of all repeating units constituting the liquid crystal polyester.

The liquid crystal polyester contained in the resin composition of the present embodiment may have other repeating units in addition to the repeating unit (i).
Examples of other repeating units include repeating units derived from aromatic hydroxycarboxylic acids other than hydroxynaphthoic acid, aromatic dicarboxylic acids, aromatic diols, aromatic hydroxyamines, and aromatic diamines.

Examples of polymerizable derivatives of compounds having a carboxy group, such as aromatic hydroxycarboxylic acids and aromatic dicarboxylic acids, include esters obtained by converting a carboxy group to an alkoxycarbonyl group or an aryloxycarbonyl group, acid halides obtained by converting a carboxy group to a haloformyl group, and acid anhydrides obtained by converting a carboxy group to an acyloxycarbonyl group.
Examples of polymerizable derivatives of compounds having a hydroxy group, such as aromatic hydroxycarboxylic acids, aromatic diols and aromatic hydroxyamines, include acylated products obtained by converting a hydroxy group into an acyloxyl group through acylation.
Examples of polymerizable derivatives of compounds having an amino group, such as aromatic hydroxyamines and aromatic diamines, include acylated products obtained by converting the amino group into an acylamino group through acylation.

The liquid crystal polyester preferably has a repeating unit represented by the following formula (1) (hereinafter referred to as "repeating unit (1)") in addition to the repeating unit (i) represented by the above formula (I).
It is preferable that the liquid crystal polyester further has, in addition to the repeating unit (i), a repeating unit represented by the following formula (2) (hereinafter referred to as "repeating unit (2)") and a repeating unit represented by the following formula (3) (hereinafter referred to as "repeating unit (3)").

(1) -O-Ar ¹ -CO-
(2) -CO-Ar ² -CO-
(3) -X ³ -Ar ³ -Y-

In the above formulas (1), (2) and (3), Ar ¹ represents a phenylene group or a biphenylylene group. Ar ² and Ar ³ each independently represent a phenylene group, a naphthylene group, a biphenylylene group or a group represented by the following formula (4), X ³ and Y each independently represent an oxygen atom or an imino group (-NH-), and the hydrogen atoms in the group represented by Ar ¹ , Ar ² or Ar ³ may each independently be substituted with a halogen atom, an alkyl group, an alkoxy group or an aryl group.

(4) -Ar ⁴ -Z-Ar ⁵ -

In the formula (4), Ar ⁴ and Ar ⁵ each independently represent a phenylene group or a naphthylene group, and Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group or an alkylidene group.

Examples of the halogen atom, alkyl group, alkoxy group, or aryl group which can be substituted for a hydrogen atom in the group represented by Ar ¹ , Ar ² , or Ar ³ include the same halogen atom, alkyl group, alkoxy group, or aryl group as those which can be substituted for a hydrogen atom in the naphthylene group in the above formula (I).
When the hydrogen atoms are substituted with these groups, the number of the substituted groups is preferably 2 or less, and more preferably 1 or less, for each of the groups represented by Ar ¹ , Ar ² or Ar ³ .

Examples of the alkylidene group include a methylene group, an ethylidene group, an isopropylidene group, an n-butylidene group, and a 2-ethylhexylidene group, and the number of carbon atoms is preferably 1 to 10.

The repeating unit (1) is a repeating unit derived from a specific aromatic hydroxycarboxylic acid. As the repeating unit (1), a repeating unit in which Ar ¹ is a 1,4-phenylene group (a repeating unit derived from 4-hydroxybenzoic acid) is preferable.

Repeating unit (2) is a repeating unit derived from a specific aromatic dicarboxylic acid. Examples of repeating unit (2) include those in which Ar ² is a 1,4-phenylene group (for example, a repeating unit derived from terephthalic acid), those in which Ar ² is a 1,3-phenylene group (for example, a repeating unit derived from isophthalic acid), those in which Ar ² is a 2,6-naphthylene group (for example, a repeating unit derived from 2,6-naphthalenedicarboxylic acid), and those in which Ar ² is a diphenylether-4,4'-diyl group (for example, a repeating unit derived from diphenylether-4,4'-dicarboxylic acid).

The repeating unit (3) is a repeating unit derived from a specific aromatic diol, aromatic hydroxylamine or aromatic diamine.
Examples of the repeating unit (3) include those in which Ar ³ is a 1,4-phenylene group (for example, repeating units derived from hydroquinone, 4-aminophenol, or 4-phenylenediamine), and those in which Ar ³ is a 4,4'-biphenylylene group (for example, repeating units derived from 4,4'-dihydroxybiphenyl, 4-amino-4'-hydroxybiphenyl, or 4,4'-diaminobiphenyl).
The repeating unit (3) is preferably a repeating unit derived from a specific aromatic diol, since this tends to result in a low melt viscosity.
The repeating unit (3) may contain a repeating unit derived from an aromatic hydroxylamine or a repeating unit derived from an aromatic diamine. However, in this case, the liquid crystal polyester may contain an amide bond, which may increase the water absorption rate, increase the dielectric constant, or decrease the thermal stability, which may cause black spots to easily occur in the molded product. From this point of view, it is preferable not to contain a repeating unit derived from these amines.

The content of the repeating unit (1) is preferably 10 mol % or more, more preferably 10 mol % to 60 mol %, still more preferably 15 mol % to 55 mol %, and particularly preferably 20 mol % to 50 mol %, based on the total amount of all repeating units (i.e., the mass of each repeating unit constituting the liquid crystal polyester is divided by the formula weight of each repeating unit to determine the substance amount equivalent (mol) of each repeating unit, and the total value).
The greater the content of the repeating unit (1), the more likely it is that the melt fluidity, heat resistance, strength and rigidity will improve. However, if the content is too high, the melting temperature and melt viscosity will tend to increase, and the temperature required for molding will tend to become higher.

The content of repeating unit (2) is preferably 35 mol% or less, more preferably 10 mol% or more and 35 mol% or less, even more preferably 15 mol% or more and 30 mol% or less, and particularly preferably 17.5 mol% or more and 27.5 mol% or less, based on the total amount of all repeating units.

The content of repeating unit (3) is preferably 35 mol% or less, more preferably 10 mol% or more and 35 mol% or less, even more preferably 15 mol% or more and 30 mol% or less, and particularly preferably 17.5 mol% or more and 27.5 mol% or less, based on the total amount of all repeating units.

The ratio of the content of repeating unit (2) to the content of repeating unit (3), expressed as [content of repeating unit (2)]/[content of repeating unit (3)] (mol/mol), is preferably 0.9/1 to 1/0.9, more preferably 0.95/1 to 1/0.95, and even more preferably 0.98/1 to 1/0.98.

The liquid crystal polyester may have two or more kinds of repeating units (1) to (3) independently.
The liquid crystal polyester may have repeating units other than the repeating unit (i) and the repeating units (1) to (3), but the content thereof is preferably 10 mol % or less, more preferably 5 mol % or less, based on the total amount of all repeating units.

The liquid crystal polyester preferably has a repeating unit (3) in which ^X3 and Y are each an oxygen atom, i.e., a repeating unit derived from a specific aromatic diol, since the melt viscosity is likely to be low. It is more preferable that the liquid crystal polyester has only a repeating unit (3) in which ^X3 and Y are each an oxygen atom.

In the liquid crystal polyester, the content of repeating units containing naphthylene groups is preferably more than 50 mol%, more preferably 55 mol% or more, even more preferably 60 mol% or more, particularly preferably 65 mol% or more, and especially preferably 70 mol% or more, based on the total amount of all repeating units.

Liquid crystal polyester is preferably produced by melt-polymerizing raw material monomers corresponding to the repeating units that make up the polyester, and then solid-phase polymerizing the resulting polymer. This makes it possible to produce a high molecular weight liquid crystal polyester with excellent heat resistance, strength, and rigidity, and is easy to handle. The melt polymerization may be carried out in the presence of a catalyst.

The flow initiation temperature of the liquid crystal polyester is preferably 250° C. or higher, more preferably 250° C. or higher and 370° C. or lower, and further preferably 275° C. or higher and 350° C. or lower.
The higher the flow initiation temperature of the liquid crystal polyester, the more the heat resistance and strength of the liquid crystal polyester tend to improve. On the other hand, when the flow initiation temperature of the liquid crystal polyester exceeds 400° C., the melting temperature and melt viscosity of the liquid crystal polyester tend to increase. Therefore, the temperature required for molding the liquid crystal polyester tends to increase.

In this specification, the flow initiation temperature of the liquid crystal polyester is also called the flow temperature or flow temperature, and is a temperature that is an indicator of the molecular weight of the liquid crystal polyester (see Naoyuki Koide, ed., Liquid Crystal Polymer - Synthesis, Forming, and Application -, CMC Corporation, June 5, 1987, p. 95).
The flow initiation temperature is the temperature at which the liquid crystalline polyester shows a viscosity of 4,800 Pa·s ( ^48,000 poise) when the liquid crystalline polyester is melted using a capillary rheometer while being heated at a rate of 4°C/min under a load of 9.8 MPa (100 kg/cm 2 ) and extruded from a nozzle having an inner diameter of 1 mm and a length of 10 mm.

In this embodiment, the liquid crystal polyester may be used alone or in combination of two or more types.

The content of the liquid crystal polyester in the resin composition of the present embodiment is preferably 90% by mass or more, more preferably 92.5% by mass or more, and even more preferably 95% by mass or more, based on 100% by mass of the total amount of the resin composition.
The content of the liquid crystal polyester in the resin composition of the present embodiment is preferably 99.9% by mass or less, more preferably 99% by mass or less, and even more preferably 98% by mass or less, based on 100% by mass of the total amount of the resin composition.
For example, the content of the liquid crystal polyester in the resin composition of this embodiment is preferably 90% by mass or more and 99.9% by mass or less, more preferably 92.5% by mass or more and 99% by mass or less, and even more preferably 95% by mass or more and 98% by mass or less, relative to 100% by mass of the total amount of the resin composition.

<Aromatic polysulfone>
The aromatic polysulfone contained in the resin composition of the present embodiment has at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group. The total amount of the functional groups (fg) contained in the aromatic polysulfone is 10 μmol/g or more.
Such aromatic polysulfones are typically resins having repeating units containing a divalent aromatic group (i.e., a residue formed by removing two hydrogen atoms bonded to an aromatic ring from an aromatic compound), a sulfonyl group (-SO ₂ -), and an oxygen atom (-O-), and which have a hydroxyl group or an amino group in the main chain or at the end of the main chain of the resin.

The aromatic polysulfone preferably has a repeating unit containing a structure represented by the following formula (S-1).
-ph1-SO ₂ -ph2-O-...(S-1)
In formula (S-1), ph1 and ph2 each independently represent a phenylene group which may have a substituent.

The phenylene group in ph1 and ph2 may be a p-phenylene group, an m-phenylene group, or an o-phenylene group, but is preferably a p-phenylene group.

Substituents that the phenylene group may have include an alkyl group, an aryl group, and a halogen atom.
The alkyl group, aryl group, or halogen atom as the substituent here may be the same as the alkyl group, aryl group, or halogen atom which can substitute for the hydrogen atom in the naphthylene group in the above formula (I).

When a hydrogen atom of the phenylene group is substituted with the above-mentioned functional group (fg), the number of such functional groups is preferably 2 or less, and more preferably 1, for each phenylene group.
The hydrogen atoms of the phenylene group may be substituted or unsubstituted, and in this embodiment, it is particularly preferred that the phenylene group is unsubstituted.
When the aromatic polysulfone has a functional group (fg) in the main chain, the phenylene group has the functional group (fg) as a substituent.

The aromatic polysulfone may contain a repeating unit containing a structure represented by the following formula (S-2) or a structure represented by the following formula (S-3) in addition to the structure represented by the above formula (S-1).
-ph3-R-ph4-O-...(S-2)
-(ph5) _n -O-...(S-3)
In formula (S-2), ph3 and ph4 each independently represent a phenylene group which may have a substituent, and R represents an alkylidene group, an oxygen atom, or a sulfur atom.
In formula (S-3), ph5 is a phenylene group which may have a substituent, n is an integer of 1 to 3, and when n is 2 or more, a plurality of ph5's may be the same or different.

Examples of ph3, ph4 and ph5 include the same phenylene groups as those in ph1 and ph2 in formula (S-1), which may have a substituent.
The alkylidene group is preferably an alkylidene group having 1 to 5 carbon atoms, and examples thereof include a methylene group, an ethylidene group, an isopropylidene group, and a 1-butylidene group.
In formula (S-3), n is preferably 1 or 2.

The aromatic polysulfone may have the functional group (fg) in the main chain or at the main chain terminals, but it is preferable that the aromatic polysulfone has the functional group (fg) at some or all of the main chain terminals.
More specifically, the aromatic polysulfone is preferably an aromatic polysulfone having a repeating unit represented by the following formula (S-1-1) and a terminal unit represented by the following formula (Se-1-1).

　式（Ｓ－１－１）中、Ｒ^１及びＲ^２は、それぞれ独立に、炭素原子数１～１０のアルキル基、又は炭素原子数６～２０のアリール基であり、ｎ１及びｎ２は、それぞれ独立に、０～４の整数であり、ｎ１又はｎ２が２以上である場合、複数個のＲ^１及びＲ^２は互いに同一でも異なっていてもよく、Ｘは、単結合又はビスフェノール若しくはビフェノールから誘導される基であり、ｎ３は１以上の整数である。

In formula (S-1-1), R ¹ and R ² each independently represent an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms; n1 and n2 each independently represent an integer from 0 to 4; when n1 or n2 is 2 or greater, multiple R ^1s and multiple R ^2s may be the same or different; X represents a single bond or a group derived from a bisphenol or biphenol; and n3 is an integer of 1 or greater.

　式（Ｓｅ－１－１）中、Ｒ_ｆｇは、ヒドロキシ基又はアミノ基であり、Ａｒ^０は、置換基を有してもよい芳香族炭化水素基であり、Ｒ^１及びＲ^２は、それぞれ独立に、炭素原子数１～１０のアルキル基、又は炭素原子数６～２０のアリール基であり、ｎ１及びｎ２は、それぞれ独立に、０～４の整数であり、ｎ１又はｎ２が２以上である場合、複数個のＲ^１及びＲ^２は互いに同一でも異なっていてもよく、＊は結合手を示す。

In formula (Se-1-1), R _fg is a hydroxy group or an amino group, Ar ⁰ is an aromatic hydrocarbon group which may have a substituent, R ¹ and R ² each independently are an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms, n1 and n2 each independently are an integer of 0 to 4, when n1 or n2 is 2 or greater, multiple R ^1s and multiple R ^2s may be the same or different, and * represents a bond.

Examples of the alkyl group having 1 to 10 carbon atoms and the aryl group having 6 to 20 carbon atoms in R ¹ and R ² in formulas (S-1-1) and (Se-1-1) include the same as those exemplified as the substituents that the phenylene group in ph1 and ph2 in formula (S-1) may have.
In formulae (S-1-1) and (Se-1-1), n1 and n2 each independently represent preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.

The group derived from bisphenol is specifically a divalent group obtained by removing one of the two hydroxyl groups of bisphenol and the hydrogen atom of the other hydroxyl group. Specific examples include groups derived from bisphenol A (also called 2,2-bis(4-hydroxyphenyl)propane), bisphenol AF (also called 2,2-bis(4-hydroxyphenyl)hexafluoropropane), bis(4-hydroxyphenyl)sulfide, bis(4-hydroxy-3-methylphenyl)sulfide, and bis(4-hydroxyphenyl)ether. Among these, the group derived from bisphenol A, that is, the divalent group obtained by removing one of the two hydroxyl groups of bisphenol A and the hydrogen atom of the other hydroxyl group, is preferred.

Groups derived from biphenol include groups derived from 4,4'-biphenol (also called 4,4'-dihydroxybiphenyl), 2,2'-dihydroxybiphenyl, 3,5,3',5'-tetramethyl-4,4'-dihydroxybiphenyl, 2,2'-diphenyl-4,4'-dihydroxybiphenyl, and 4,4'''-dihydroxy-p-quarterphenyl, and groups derived from 4,4'-biphenol, i.e., divalent groups obtained by removing one of the two hydroxyl groups of 4,4'-biphenol and the hydrogen atom of the other hydroxyl group, are preferred.

X is preferably a single bond.
n3 is preferably 5 to 600.
In formula (Se-1-1), the aromatic hydrocarbon group in Ar ⁰ is a hydrocarbon group having at least one aromatic ring. This aromatic ring is not limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic, or may be an aromatic heterocycle in which a part of the carbon atoms constituting the ring is substituted with a heteroatom. Examples of the aromatic ring in the aromatic hydrocarbon group include a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthrene ring, and among these, a benzene ring is preferred. That is, the aromatic hydrocarbon group in Ar ⁰ is preferably a phenylene group.
Examples of the substituent that the aromatic hydrocarbon group in Ar ⁰ may have include an alkyl group and an aryl group. The alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, an n-hexyl group, a 2-ethylhexyl group, an n-octyl group, and an n-decyl group. The aryl group is preferably an aryl group having 6 to 20 carbon atoms, and specific examples thereof include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 1-naphthyl group, and a 2-naphthyl group.

The total amount of at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group contained in the aromatic polysulfone is 10 μmol/g or more.
When the functional group (fg) is a hydroxy group, the content of the hydroxy group in the aromatic polysulfone is preferably 20 μmol/g or more, more preferably 30 to 200 μmol/g, more preferably 40 to 180 μmol/g, even more preferably 45 to 170 μmol/g, and particularly preferably 50 to 160 μmol/g.
When the functional group (fg) is an amino group, the content of the amino group in the aromatic polysulfone is preferably 10 to 200 μmol/g, more preferably 15 to 190 μmol/g, further preferably 20 to 180 μmol/g, and particularly preferably 165 to 180 μmol/g.
When the total amount of at least one functional group (fg) selected from the group consisting of hydroxyl groups and amino groups contained in the aromatic polysulfone is within the above preferred range, the effect of reducing the anisotropy of the liquid crystal polyester is more easily obtained in the resin composition.

The hydroxyl group content and amino group content of aromatic polysulfone can be measured as follows.

[Method for measuring the content of hydroxy groups in aromatic polysulfone]
First, a predetermined amount (unit: g) of aromatic polysulfone is dissolved in dimethylformamide, and then p-toluenesulfonic acid is added to neutralize the potassium phenoxide in the aromatic polysulfone to form a phenolic hydroxyl group.
Next, the unreacted p-toluenesulfonic acid in the obtained solution is neutralized with a mixed solution of toluene and methanol (toluene/methanol=80/20 (v/v)) containing 0.05 mol/L of potassium methoxide relative to the total amount (L) of the solution using a potentiometer. This determines the number of moles of p-toluenesulfonic acid used in the reaction, and the number of moles of potassium phenoxide in the aromatic polysulfone can be determined from the number of moles of p-toluenesulfonic acid.
The phenolic hydroxyl groups are then neutralized, and the number of moles of the phenolic hydroxyl groups is calculated from the number of moles of potassium methoxide used to neutralize the phenolic hydroxyl groups. The number of moles of the phenolic hydroxyl groups in a given amount (unit: g) of aromatic polysulfone is calculated from the difference between the number of moles of the phenolic hydroxyl groups and the number of moles of potassium phenoxide.
The obtained number of moles of phenolic hydroxyl groups is divided by the above-mentioned predetermined amount (unit: g) of aromatic polysulfone to determine the content of phenolic hydroxyl groups in the aromatic polysulfone, i.e., the content of hydroxyl groups in the aromatic polysulfone (unit: μmol/g).

[Method for measuring the content of amino groups in aromatic polysulfone]
The amino group content of the aromatic polysulfone is calculated by ¹ H-NMR measurement. The specific calculation method is as follows.
(i) In the repeating unit of the main chain of aromatic polysulfone, the peak area A assigned to the hydrogen atoms bonded to the aromatic ring of the main chain, the number of hydrogen atoms of which is already known, is determined by ¹ H-NMR measurement.
(ii) The number of repeating units (unit number) can be calculated by dividing the peak area A by the number of hydrogen atoms bonded to the aromatic rings in the main chain of the aromatic polysulfone (for example, when the peak area A is the peak area attributable to four hydrogen atoms bonded to the aromatic rings in the main chain, it is divided by 4).
(iii) The peak area B assigned to the hydrogen atom bonded to the carbon atom adjacent to the carbon atom bonded to the amino group in the aromatic ring at the main chain terminal of the aromatic polysulfone is determined by ¹ H-NMR measurement.
(iv) The number of amino groups can be calculated by dividing the peak area B by the number of hydrogen atoms bonded to the carbon atom adjacent to the carbon atom to which the amino group is bonded. For example, when the peak area B is the peak area attributable to two hydrogen atoms bonded to the carbon atom adjacent to the carbon atom to which the amino group is bonded, it is divided by 2.
(v) The number of amino groups determined in (iv) is divided by the number of repeating units determined in (ii) and then multiplied by 100 (100 units), thereby calculating the amount of amino groups per 100 repeating units forming the main chain of the aromatic polysulfone.

The measurement solvent in the ¹ H-NMR measurement may be any solvent that allows ¹ H-NMR measurement and is capable of dissolving aromatic polysulfone, and deuterated dimethyl sulfoxide is preferred.

Such aromatic polysulfones can be produced by polycondensing a dihalogeno aromatic sulfone compound and a dihydroxy aromatic compound corresponding to the repeating units constituting the aromatic polysulfones.
The monomers serving as raw materials for such aromatic polysulfone may be either synthesized or commercially available.
The total amount of functional groups (fg) possessed by the aromatic polysulfone can be controlled by the amounts of monomers used as raw materials in polycondensation, reaction conditions for polycondensation, and the like.

The reduced viscosity (unit: dL/g) of aromatic polysulfone is preferably 0.20 dL/g or more and 0.76 dL/g or less, and more preferably 0.24 dL/g or more and 0.60 dL/g or less. The reduced viscosity of aromatic polysulfone is determined as follows. 1 g of aromatic polysulfone is dissolved in N,N-dimethylformamide to obtain a solution with a volume of 1 dL. The viscosity (η) of this solution is measured at 25°C using an Ostwald type viscosity tube. The viscosity (η0) of the solvent N,N-dimethylformamide is measured at 25°C using an Ostwald type viscosity tube. As the concentration of the above solution is 1 g/dL, the value of the specific viscosity ((η-η0)/η0) is the reduced viscosity value in units of dL/g.

The number average absolute molecular weight of the aromatic polysulfone is preferably 1000 or more, more preferably 2000 or more, and even more preferably 4000 or more. The number average absolute molecular weight of the aromatic polysulfone is preferably 30000 or less, more preferably 25000 or less, and even more preferably 15000 or less.
When the number average absolute molecular weight of the aromatic polysulfone is equal to or higher than the lower limit of the above-mentioned preferred range, the mechanical strength of the molded article is further improved, whereas when the number average absolute molecular weight is equal to or lower than the upper limit of the above-mentioned preferred range, the functional group (fg) per mass of the aromatic polysulfone can be increased, making it easier to control the properties.
For example, the number average absolute molecular weight of the aromatic polysulfone is preferably from 1,000 to 30,000, more preferably from 2,000 to 25,000, even more preferably from 4,000 to 20,000, and particularly preferably from 4,000 to 15,000. In another aspect, the number average absolute molecular weight of the aromatic polysulfone is preferably from 4,000 to 9,000, or from 9,000 to 20,000.
The number average absolute molecular weight of the aromatic polysulfone referred to here is calculated by gel permeation chromatography (GPC) analysis.

In this embodiment, the aromatic polysulfone may be used alone or in combination of two or more types.

The content of aromatic polysulfone in the resin composition of the present embodiment is preferably 10% by mass or less, more preferably 7.5% by mass or less, and even more preferably 5% by mass or less, based on 100% by mass of the total amount of the resin composition. The content of aromatic polysulfone in the resin composition of the present embodiment is preferably 0.1% by mass or more, more preferably 1% by mass or more, and even more preferably 2% by mass or more, based on 100% by mass of the total amount of the resin composition.
For example, the content of aromatic polysulfone in the resin composition of this embodiment is preferably 0.1% by mass or more and 10% by mass or less, more preferably 1% by mass or more and 7.5% by mass or less, and even more preferably 2% by mass or more and 5% by mass or less, relative to 100% by mass of the total amount of the resin composition.

Alternatively, the content of the aromatic polysulfone in the resin composition of this embodiment is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 7.5 parts by mass or less, and even more preferably 2 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the total content of the liquid crystal polyester and the aromatic polysulfone.
When the content of aromatic polysulfone in the resin composition is equal to or more than the lower limit of the above-mentioned preferred range, the effect of reducing the anisotropy of the liquid crystal polyester is more easily obtained. On the other hand, when the content of aromatic polysulfone in the resin composition is equal to or less than the upper limit of the above-mentioned preferred range, both electrical properties and manufacturing processability are likely to be good.

<Other ingredients>
The resin composition of the present embodiment may contain other components, as necessary, in addition to the specific liquid crystal polyester and the specific aromatic polysulfone described above.
The other components include a solvent, a filler, a resin other than the specific liquid crystal polyester and the specific aromatic polysulfone described above, and additives.

[Method for preparing resin composition]
The resin composition of the present embodiment can be obtained by mixing the specific liquid crystal polyester and the specific aromatic polysulfone described above, and, if necessary, other components.
For example, a specific liquid crystal polyester, a specific aromatic polysulfone, and other components as necessary are mixed in a twin-screw extruder all at once or in a suitable order while being heated, and then granulated to obtain a pellet-shaped resin composition. The heating temperature at that time is preferably set within a range of, for example, the flow starting temperature of the liquid crystal polyester plus 10°C to the flow starting temperature of the liquid crystal polyester plus 50°C.

In the resin composition of the present embodiment described above, the hydroxyl group and amino group of the functional group (fg) of the aromatic polysulfone are more likely to interact with the liquid crystal polyester than halogen atoms such as chlorine. Therefore, by mixing an aromatic polysulfone having a certain proportion or more of the functional group (fg) with the liquid crystal polyester, it is believed that the liquid crystal polyester is less likely to be oriented in the flow direction (MD), and the difference in properties between the MD and the direction perpendicular to the MD (TD) is less likely to occur. For example, the difference in the linear expansion coefficient between the MD and TD of the molded product can be reduced.
Therefore, according to the resin composition of the present embodiment, a molded article in which the anisotropy of the liquid crystal polyester is alleviated can be easily obtained.

In addition, the liquid crystal polyester used in the resin composition of this embodiment has a repeating unit (i) represented by formula (I). The monomer providing this repeating unit (i) is a monomer effective for reducing the dielectric loss tangent. Therefore, the resin composition containing such a specific liquid crystal polyester can provide a molding material with a further reduced dielectric loss tangent.
Therefore, the resin composition of this embodiment has excellent electrical properties (low dielectric tangent, low relative dielectric constant), and further, the anisotropy is reduced.

The present invention has the following aspects:

[6] A liquid crystal polyester composition comprising a liquid crystal polyester and an aromatic polysulfone,
The liquid crystal polyester has a repeating unit (i) represented by the above formula (I),
The aromatic polysulfone has a hydroxy group,
The content of hydroxy groups in the aromatic polysulfone is 20 μmol/g or more, preferably 30 to 200 μmol/g, more preferably 40 to 180 μmol/g, more preferably 45 to 170 μmol/g, and even more preferably 50 to 160 μmol/g.

[7] A liquid crystal polyester composition comprising a liquid crystal polyester and an aromatic polysulfone,
The liquid crystal polyester has a repeating unit (i) represented by the above formula (I),
The aromatic polysulfone has an amino group,
The content of amino groups in the aromatic polysulfone is 10 μmol/g or more, preferably 10 to 200 μmol/g, more preferably 15 to 190 μmol/g, more preferably 20 to 180 μmol/g, and even more preferably 165 to 180 μmol/g.

[8] The resin composition according to [1], [6] or [7], wherein the number of the repeating units (i) contained in the liquid crystal polyester is 40 mol% or more, preferably 40 mol% or more and 90 mol% or less, more preferably 45 mol% or more and 85 mol% or less, and even more preferably 50 mol% or more and 80 mol% or less, relative to the total number (100 mol%) of all repeating units constituting the liquid crystal polyester.

[9] The resin composition according to any one of [1] and [6] to [8], wherein the content of the aromatic polysulfone is 0.1 parts by mass or more and 10 parts by mass or less, preferably 1 part by mass or more and 7.5 parts by mass or less, and more preferably 2 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the total content of the liquid crystal polyester and the aromatic polysulfone.

[10] The resin composition according to any one of [1] to [3] and [6] to [9], wherein the liquid crystal polyester is a liquid crystal polyester having the repeating unit (i), the repeating unit (2) represented by the above formula (2), and the repeating unit (3) represented by the above formula (3).

[11] The resin composition according to any one of [1] to [3] and [6] to [9], wherein the liquid crystal polyester is a liquid crystal polyester having the repeating unit (i) and the repeating unit (1) represented by the above formula (1).

[12] The resin composition according to any one of [1] to [3] and [6] to [11], wherein the aromatic polysulfone has a repeating unit represented by the above formula (S-1-1) and a terminal unit represented by the above formula (Se-1-1).

[13] A liquid crystal alignment control agent for controlling the alignment of a liquid crystal polyester, comprising:
A liquid crystal alignment control agent comprising an aromatic polysulfone having 10 μmol/g or more of at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group.
[14] Use of an aromatic polysulfone having 10 μmol/g or more of at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group, for producing a liquid crystal alignment control agent for controlling the alignment of a liquid crystal polyester.
[15] Use of an aromatic polysulfone having 10 μmol/g or more of at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group for controlling the alignment of a liquid crystal polyester.
[16] A method for controlling the orientation of a liquid crystal polyester, comprising adding an effective amount of an aromatic polysulfone having 10 μmol/g or more of at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group to a resin composition containing a liquid crystal polyester.
Here, the liquid crystal polyester and aromatic polysulfone in the embodiment described in any one of [13] to [16] above may be the resin composition described in any one of [1] to [3] and [6] to [11] above, or the liquid crystal polyester and aromatic polysulfone described in this specification.
Furthermore, the resin composition according to any one of [1] to [3] and [6] to [11] above may be granulated at a heating temperature of 325° C. according to the method described in <Preparation of Resin Composition> below to obtain a pellet-shaped resin composition, and then the pellet-shaped resin composition is injection molded at a molding temperature of 330° C. according to the method described in <Production of Molded Article> below to produce a flat plate of 30 mm × 30 mm × 0.3 mm. The flat plate is heat-treated at 340° C. for 1 hour under a nitrogen atmosphere, and the linear expansion coefficient CTE (unit: × 10 ⁻⁵ (1/K)) from 50° C. to 100° C. in each of the injection molding direction (MD) and the direction perpendicular to the MD (TD) of the flat plate is measured. The absolute value of the difference between MD and TD is calculated. The absolute value of the difference between MD and TD is 0 or more and 5 or less, preferably more than 0 and 4 or less, more preferably more than 0 and 3 or less, and even more preferably 0.1 or more and 2.7 or less.
In addition, the molded article described in [4] above and the film described in [5] above may be a molded article and a film containing the resin composition described in any one of [6] to [11] above.

(Molded products)
One embodiment of the molded article contains the above-mentioned resin composition.
The molded article of the present embodiment can be obtained by a known molding method using the above-mentioned resin composition.
The method for forming a molded article from the resin composition is preferably a melt molding method, examples of which include injection molding, extrusion molding, compression molding, blow molding, vacuum molding, and press molding.

For example, when a resin composition is used as a molding material and molding is performed by injection molding, the resin composition is melted using a known injection molding machine, and the molten resin composition is injected into a mold to perform molding.
The cylinder temperature of the injection molding machine is appropriately determined depending on, for example, the type of liquid crystal polyester, and is preferably set to a temperature 10 to 50°C higher than the flow initiation temperature, for example 300 to 400°C.

The molded product of this embodiment can be used, for example, in automobile parts and electronic parts such as connectors, sockets, bobbins, and relay parts.

(film)
FIG. 1 is a cross-sectional view showing one embodiment of a film.
The film 10 shown in FIG. 1 contains the above-mentioned resin composition.
The film 10 can be produced by melt molding the above-mentioned resin composition.
Examples of the melt molding method include extrusion molding methods such as a T-die method and an inflation method.
Even if the film 10 is produced using, for example, a T-die method, the anisotropy is reduced because the film 10 contains the resin composition of this embodiment.

In addition, since the film 10 is made of a resin composition containing a liquid crystal polyester having a repeating unit (i) represented by formula (I), it is also effective in imparting electrical properties (e.g., low dielectric tangent, low dielectric constant).
Therefore, the film 10 is applicable to, for example, a film for a resonator, a filter, an antenna, a circuit board, a laminated circuit element board, etc. The film 10 can be suitably used as a film for a high-frequency or high-speed circuit board, etc.

The above describes a preferred embodiment of the present invention with reference to the attached drawings, but it goes without saying that the present invention is not limited to such an embodiment. The above-mentioned embodiment is merely an example, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[Measurement of Flow Initiation Temperature of Liquid Crystal Polyester]
Using a flow tester ("CFT-500EX" manufactured by Shimadzu Corporation), about 2 g of liquid crystal polyester as a sample was filled into a cylinder equipped with a die having a nozzle with an inner diameter of 1 mm and a length of 10 mm, and the sample was melted and extruded from the nozzle while heating at a rate of 4°C/min under a load of 9.8 MPa. The temperature at which the liquid crystal polyester showed a viscosity of 4800 Pa s was measured and defined as the flow initiation temperature.

[Measurement of the Content of Hydroxy Groups in Aromatic Polysulfone]
First, a predetermined amount (unit: g) of aromatic polysulfone was dissolved in dimethylformamide, and then p-toluenesulfonic acid was added to neutralize the potassium phenoxide in the aromatic polysulfone to form a phenolic hydroxyl group.
Next, the unreacted p-toluenesulfonic acid in the obtained solution was neutralized with a mixed solution of toluene and methanol (toluene/methanol=80/20 (v/v)) containing 0.05 mol/L of potassium methoxide relative to the total amount (L) of the solution using a potentiometer. This determined the number of moles of p-toluenesulfonic acid used in the reaction, and the number of moles of potassium phenoxide in the aromatic polysulfone was determined from the number of moles of p-toluenesulfonic acid.
Furthermore, the phenolic hydroxyl groups were neutralized, and the number of moles of the phenolic hydroxyl groups was calculated from the number of moles of potassium methoxide used for neutralizing the phenolic hydroxyl groups. The number of moles of the phenolic hydroxyl groups in a given amount (unit: g) of aromatic polysulfone was calculated from the difference between the number of moles of the phenolic hydroxyl groups and the number of moles of potassium phenoxide.
The obtained number of moles of phenolic hydroxyl groups was divided by the above-mentioned predetermined amount (unit: g) of aromatic polysulfone to obtain the content of phenolic hydroxyl groups in the aromatic polysulfone, i.e., the content of hydroxyl groups in the aromatic polysulfone (unit: μmol/g).

[Measurement of Amino Group Content in Aromatic Polysulfone]
The amino group content of the aromatic polysulfone was measured by an NMR method.
Specifically, aromatic polysulfone was dissolved in a solvent of deuterated dimethyl sulfoxide, and in ¹ H-NMR measurement, the peak area (1H _NH2 ) of two protons bonded to the carbon adjacent to the aromatic carbon substituted with an amino group and the peak area (1H _PES ) of four protons adjacent to the aromatic carbon derived from the structural unit of aromatic polysulfone were observed. Based on these peak areas, the amount of terminal units (H 2 N-C 6 H 4 -) having an amino group per 100 structural units represented by the general formula (S-1): -Ph1-SO _{2 -Ph2 -} O- (wherein _ph1 and ph2 are each independently a phenylene group which may have a substituent) was calculated by the following formula. The obtained amount of amino terminal units (amino group content) was converted into μmol/g.
[Amount of terminal units having amino groups (units/100 units)]
= [peak area of 1H _NH2 when the peak area of 1H _PES is taken as 100] × 2

The measurement apparatus and conditions used in the NMR measurement are as follows: [Measurement apparatus]
NMR device: Varian NMR System PS400WB
Magnetic field strength: 9.4T (400MHz)
Probe: Varian 400 DB AutoX WB Probe (5 mm)

[Solution ¹ H-NMR measurement conditions]
Measurement nucleus: 1H
Measurement method: Single pulse method Measurement temperature: 50°C
Heavy solvent: d6-DMSO (contains TMS)
Waiting time: 10 seconds
Pulse irradiation time: 11.9 μsec (90° C. pulse)
Number of accumulations: 64 External standard: TMS (0 ppm)

[Measurement of coefficient of linear expansion (CTE)]
A flat plate was molded as a sample for measurement.
A thermal analyzer (manufactured by Rigaku Corporation, model: TMA8310) was used to measure the linear expansion coefficient CTE (unit: ×10 ^-5 (1/K)) from 50° C. to 100° C. in both the MD and TD directions of the flat plate.

<Production of Liquid Crystal Polyester>
The liquid crystal polyester A and the liquid crystal polyester B used in this example were each produced as follows.

Method for producing liquid crystal polyester A:
Into a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer, and a reflux condenser, 1035.0 g of 6-hydroxy-2-naphthoic acid, 255.2 g of hydroquinone, 378.3 g of 2,6-naphthalenedicarboxylic acid, 83.1 g of terephthalic acid, 1189.9 g of acetic anhydride, and 0.175 g of 1-methylimidazole as a catalyst were added, and the mixture was stirred at room temperature for 15 minutes, and then heated with stirring. When the internal temperature reached 140° C., the mixture was stirred for 1 hour while maintaining the same temperature.
Next, the temperature was raised from 140°C to 310°C over 4 hours and 40 minutes while distilling off the by-product acetic acid and unreacted acetic anhydride. The temperature was maintained at 310°C for 1 hour and 30 minutes to obtain an aromatic polyester. The obtained aromatic polyester was cooled to room temperature and pulverized in a pulverizer to obtain an aromatic polyester powder (particle size: about 0.1 mm to about 1 mm). The flow initiation temperature of this powder (aromatic liquid crystal polyester) was measured using a flow tester and found to be 274°C.
The obtained powder was heated from 25°C to 260°C over 1 hour, then heated from the same temperature of 260°C to 284°C over 3 hours, and then kept at the same temperature of 284°C for 5 hours to carry out solid-phase polymerization. The powder after solid-phase polymerization was then cooled to obtain liquid crystal polyester A. The flow initiation temperature of the cooled powder (liquid crystal polyester A) was measured using a flow tester and found to be 311°C. The number of repeating units derived from 6-hydroxy-2-naphthoic acid in liquid crystal polyester A was 55 mol% relative to the total number (100 mol%) of all repeating units constituting liquid crystal polyester A.

Manufacturing method of liquid crystal polyester B:
In a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 911.6 g of 4-hydroxybenzoic acid, 409.7 g of 4,4'-biphenol, 274.1 g of terephthalic acid, 91.4 g of isophthalic acid, 1235.3 g of acetic anhydride and 0.169 g of 1-methylimidazole as a catalyst were added, and the mixture was stirred at room temperature for 15 minutes, and then heated while stirring. When the internal temperature reached 140°C, the mixture was stirred for 1 hour while maintaining the same temperature. Next, the mixture was heated from 140°C to 305°C over 4 hours and 30 minutes while distilling off the by-product acetic acid and unreacted acetic anhydride. The mixture was kept at the same temperature of 305°C for 50 minutes to obtain an aromatic polyester. The obtained aromatic polyester was cooled to room temperature and pulverized with a pulverizer to obtain an aromatic polyester powder (particle size: about 0.1 mm to about 1 mm). The flow initiation temperature of this powder (aromatic liquid crystal polyester) was measured using a flow tester and found to be 265°C.
The obtained powder was heated from 25°C to 235°C over 1 hour, then heated from the same temperature of 235°C to 284°C over 6 hours and 20 minutes, and then kept at the same temperature of 284°C for 5 hours to perform solid-phase polymerization. The powder after solid-phase polymerization was then cooled to obtain liquid crystal polyester B. The flow initiation temperature of the cooled powder (liquid crystal polyester B) was measured using a flow tester and found to be 330°C.

<Production of aromatic polysulfone>
The aromatic polysulfones C, D, E and F used in this example were each produced as follows.

Method for producing aromatic polysulfone C:
In a polymerization tank equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser with a receiver at the tip, bis(4-hydroxyphenyl)sulfone (300.3 g), bis(4-chlorophenyl)sulfone (330.8 g), and diphenylsulfone (560.3 g) as a polymerization solvent were charged, and the temperature was raised to 180 ° C. while circulating nitrogen gas in the system to obtain a solution. After potassium carbonate (159.7 g) was added to the obtained solution, the temperature was gradually raised to 290 ° C., and the reaction was carried out at 290 ° C. for another 3 hours. The obtained reaction liquid was cooled to room temperature to solidify, finely pulverized, washed with hot water and with a mixed solvent of acetone and methanol several times, and then dried by heating at 150 ° C. to obtain an aromatic polysulfone C powder. The content of phenolic hydroxyl groups in the obtained aromatic polysulfone C was measured and found to be 160 μmol / g.
The number average absolute molecular weight of the resulting aromatic polysulfone C was 10000. The product was further pulverized by an impact pulverizer and classified to obtain aromatic polysulfone C fine particles (D50 value: 500 μm).

Method for Producing Aromatic Polysulfone D:
In a polymerization tank equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser with a receiver at the tip, bis(4-hydroxyphenyl)sulfone (300.3 g), bis(4-chlorophenyl)sulfone (346.3 g), and diphenylsulfone (570.1 g) as a polymerization solvent were charged, and the temperature was raised to 180 ° C. while circulating nitrogen gas in the system to obtain a solution. After potassium carbonate (170.8 g) was added to the obtained solution, the temperature was gradually raised to 290 ° C., and the reaction was continued at 290 ° C. for another 1 hour and 30 minutes. The obtained reaction liquid was cooled to room temperature to solidify, finely pulverized, washed with hot water and with a mixed solvent of acetone and methanol several times, and then dried by heating at 150 ° C. to obtain an aromatic polysulfone D powder. The content of phenolic hydroxyl groups in the obtained aromatic polysulfone D was measured and found to be 55 μmol / g.
The number average absolute molecular weight of the resulting aromatic polysulfone D was 18000. The product was further pulverized by an impact pulverizer and classified to obtain aromatic polysulfone D fine particles (D50 value: 540 μm).

Method for Producing Aromatic Polysulfone E:
In a polymerization tank equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser with a receiver at its tip, bis(4-hydroxyphenyl)sulfone (300.3 g), bis(4-chlorophenyl)sulfone (365.3 g), and diphenylsulfone (594.0 g) as a polymerization solvent were charged, and the temperature was raised to 180° C. while circulating nitrogen gas in the system to obtain a solution. Potassium carbonate (172.5 g) was added to the obtained solution, and the temperature was gradually raised to 288° C., and the reaction was continued at 288° C. for another 3 hours. The obtained reaction liquid was cooled to room temperature to solidify, finely pulverized, washed with hot water and with a mixed solvent of acetone and methanol several times, and then dried by heating at 150° C. to obtain an aromatic polysulfone E powder. The content of phenolic hydroxyl groups in the obtained aromatic polysulfone E was measured and found to be 5.2 μmol/g.
The number average absolute molecular weight of the resulting aromatic polysulfone E was 14000. The product was further pulverized by an impact pulverizer and classified to obtain aromatic polysulfone E fine particles (D50 value: 520 μm).

Method for producing aromatic polysulfone F:
In a polymerization tank equipped with a stirrer, a nitrogen inlet tube, a thermometer, and a condenser with a receiver at its tip, 3.57 parts by mass of potassium carbonate, 5.13 parts by mass of bis(4-chlorophenyl)sulfone, and 120 parts by mass of N-methyl-2-pyrrolidone were added and mixed, and the temperature was raised to 100°C, and then 120 parts by mass of polyethersulfone (Sumitomo Chemical Co., Ltd., Sumika Excel PES3600P) was added. After the polyethersulfone was dissolved, the temperature was raised to 190°C, and then a mixture of 4.53 parts by mass of 4-aminophenol and 60 parts by mass of N-methyl-2-pyrrolidone (NMP) was dropped, and the temperature was raised to 200°C and reacted for 10 hours. Theoretically, the molar ratio (amino compound/halogen atom) of the amino compound (4-aminophenol) to the halogen atom at the end of the aromatic halogenosulfone compound (total Cl atoms at the ends of polyethersulfone and bis(4-chlorophenyl)sulfone) was 0.8.
The reaction mixture was then diluted with NMP and cooled to room temperature to precipitate unreacted potassium carbonate and by-produced potassium chloride. The reaction mixture after the above-mentioned precipitation operation was dropped into water to precipitate aromatic polysulfone, and unnecessary NMP was removed by filtration to obtain a precipitate. The precipitate was thoroughly washed repeatedly with water and dried by heating at 150°C to obtain an amino group-containing aromatic polysulfone having an amino group at at least one end of the main chain, i.e., aromatic polysulfone F.
The content of phenolic hydroxyl groups in the obtained aromatic polysulfone F was measured to be 0.2 μmol/g. The content of amino groups in the obtained aromatic polysulfone F was measured to be 172 μmol/g.
The number average absolute molecular weight of the resulting aromatic polysulfone F was 6600. The product was further pulverized by an impact pulverizer and classified to obtain aromatic polysulfone F fine particles (D50 value: 43 μm).

<Preparation of Resin Composition>
The liquid crystal polyester and aromatic polysulfone were mixed in the ratio shown in Table 1, and pelletized by a twin-screw extruder to obtain a pellet-shaped resin composition.
In preparing the resin compositions of Examples 1 to 6 and Comparative Examples 1 to 3, the resin compositions were granulated at a heating temperature of 325° C. In preparing the resin compositions of Comparative Examples 4 to 6, the resin compositions were granulated at a heating temperature of 345° C.

<Production of Molded Products>
The resulting pelletized resin composition was injection molded to obtain a flat plate of 30 mm×30 mm×0.3 mm.
When the resin compositions of Examples 1 to 6 and Comparative Examples 1 to 3 were used, injection molding was performed at a molding temperature of 330° C. When the resin compositions of Comparative Examples 4 to 6 were used, injection molding was performed at a molding temperature of 350° C.

<Evaluation>
The molded plate obtained above was heat-treated at 340°C for 1 hour in a nitrogen atmosphere, and the linear expansion coefficient CTE (unit: ×10 ^-5 (1/K)) from 50°C to 100°C was measured in the injection molding direction (MD) and in the direction perpendicular to the MD (TD) of the plate, and the absolute value of the difference between MD and TD was calculated. The results are shown in Table 1.

Comparing Comparative Example 1, Comparative Examples 2-3, and Examples 1-6, it can be seen that the resin compositions of Examples 1-6, which contain aromatic polysulfone in which the total amount of at least one functional group (fg) selected from the group consisting of hydroxyl groups and amino groups is 10 μmol/g or more, have an enhanced effect of reducing anisotropy.

Comparing Comparative Example 4, Comparative Examples 5-6, and Examples 1-2, it can be confirmed that the present invention is useful for the resin compositions of Examples 1-2, which contain a liquid crystal polyester having a repeating unit (i) represented by formula (I).

10. Film

Claims (5)

Contains a liquid crystal polyester and an aromatic polysulfone,
The liquid crystal polyester has a repeating unit (i) represented by the following formula (I):
The aromatic polysulfone has at least one functional group (fg) selected from the group consisting of a hydroxy group and an amino group,
A resin composition, wherein the total amount of the functional groups (fg) contained in the aromatic polysulfone is 10 μmol/g or more.

[In formula (I), some or all of the hydrogen atoms in the naphthylene group may be substituted with a halogen atom, an alkyl group, an alkoxy group or an aryl group.] The resin composition according to claim 1, wherein the number of repeating units (i) contained in the liquid crystal polyester is 40 mol% or more relative to the total number (100 mol%) of all repeating units constituting the liquid crystal polyester. The resin composition according to claim 1, wherein the content of the aromatic polysulfone is 0.1 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the total content of the liquid crystal polyester and the aromatic polysulfone. A molded article containing the resin composition according to any one of claims 1 to 3. A film containing the resin composition according to any one of claims 1 to 3.

Images