JP2018080242A - Liquid crystal polymer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal polymer composition that has a low melt viscosity, and shows balanced improvements in tracking breakdown resistance, the anisotropy of mold shrinkage rates, and thermal conductivities.SOLUTION: A liquid crystal polymer composition contains, based on a liquid crystal polymer of 100 pts.wt., a tabular filler with a particle size of 1-8 μm of 60-150 pts.wt., and has a comparative tracking index of 250 V or more.SELECTED DRAWING: None

Description

  The present invention relates to a liquid crystal polymer composition having improved tracking fracture resistance, anisotropy in molding shrinkage, and improved thermal conductivity.

In the liquid crystal polymer, molecules are rigid and hardly entangled even in a molten state, and molecular chains are remarkably aligned in the flow direction of the resin by shearing during molding.
For this reason, the liquid crystal polymer has good fluidity and is difficult to produce burrs, and has excellent mechanical properties such as heat resistance and rigidity, chemical resistance, dimensional accuracy, etc. The amount of electric / electronic parts having a large increase is greatly increased.
However, electrical and electronic parts used in the information / communication field have become lighter, thinner, more complex, and more integrated in recent years, and have higher tracking breakdown resistance than liquid crystal polymer compositions. It is demanded that the anisotropy of the shrinkage rate is low and the heat dissipation is high.

  As a method for improving the anisotropy of the molding shrinkage of the liquid crystal polymer, a method of blending a specific fibrous inorganic filler and a plate-like inorganic filler with the liquid crystal polymer has been proposed (Patent Document 1). However, although this method improves the anisotropy of the molding shrinkage to some extent, it is not sufficient.

  As a method for imparting heat dissipation to liquid crystal polyester, for example, a method for improving thermal conductivity by adding alumina having a specific particle diameter and a plate-like filler to a thermoplastic resin has been proposed (Patent Document 2). However, in this method, since alumina fine particles are added, the screw and cylinder of the extruder at the time of kneading, the screw, cylinder and mold of the molding machine at the time of molding may be worn, and the molding shrinkage rate may be different. The effect of improving the directionality was not sufficient.

  A method of improving thermal conductivity by adding a plate-like filler having a specific particle diameter and a granular filler to a liquid crystal polymer has been proposed (Patent Document 3). In this method, granular titanium oxide is added. For this reason, there is a risk that the screw or the like may be worn, and the resin composition is deteriorated so that mechanical properties and the like are easily impaired.

  Therefore, there has been a demand for a method of improving the balance between tracking fracture resistance, molding shrinkage anisotropy and thermal conductivity in a balanced manner while maintaining fluidity without blending an alumina filler or a titanium oxide filler.

JP 2011-190461 A JP 2009-263640 A JP 2009-127026 A

  An object of the present invention is to provide a liquid crystal polymer composition having a low melt viscosity, good mechanical strength, and improved balance resistance in tracking fracture resistance, molding shrinkage anisotropy and thermal conductivity. It is in.

  The liquid crystal polymer composition of the present invention contains a plate-like filler having a specific particle size, so that the fluidity and mechanical strength are maintained, while the tracking fracture resistance, the anisotropy of molding shrinkage, and the thermal conductivity are high. It is an improvement.

  That is, the present invention contains 60 to 150 parts by weight of a plate-like filler (A) having a particle diameter of 1 to 8 μm with respect to 100 parts by weight of the liquid crystal polymer, and a liquid crystal polymer composition having a comparative tracking index of 250 V or more. I will provide a.

  The liquid crystal polymer composition of the present invention has a low melt viscosity, and can provide a molded product having a good balance of molding shrinkage anisotropy, tracking fracture resistance and thermal conductivity, so that a switch, relay, connector, It is useful as a molding material for electrical and electronic parts such as chips, optical pickups, inverter transformers, coil bobbins, antennas, sensors, and substrates.

FIG. 1 shows a schematic diagram of a laminate of bar flow test pieces prepared for measurement of thermal conductivity in Examples and an evaluation sample cut out therefrom.

  The liquid crystal polymer used in the liquid crystal polymer composition of the present invention is a liquid crystal polyester resin or liquid crystal polyester amide resin that forms an anisotropic molten phase called a thermotropic liquid crystal polymer by those skilled in the art.

  The property of the anisotropic molten phase of the liquid crystal polymer can be confirmed by a normal deflection inspection method using an orthogonal deflector, that is, by observing a sample placed on a hot stage in a nitrogen atmosphere.

  As the liquid crystal polymer used in the present invention, either a semi-aromatic liquid crystal polymer having an aliphatic group in a molecular chain or a wholly aromatic liquid crystal polymer in which the molecular chain is entirely composed of an aromatic group may be used. Among these liquid crystal polymers, it is preferable to use a wholly aromatic liquid crystal polymer, particularly a wholly aromatic liquid crystal polyester resin, because of good flame retardancy and mechanical properties.

  As the repeating unit constituting the liquid crystal polymer used in the present invention, aromatic oxycarbonyl repeating unit, aromatic dicarbonyl repeating unit, aromatic dioxy repeating unit, aromatic aminooxy repeating unit, aromatic diamino repeating unit, aromatic Examples thereof include aminocarbonyl repeating units, aromatic oxydicarbonyl repeating units, aliphatic dioxy repeating units, aliphatic dicarbonyl repeating units, and combinations thereof.

  Specific examples of the monomer that gives an aromatic oxycarbonyl repeating unit include, for example, 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 2-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 5-hydroxy- 2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 4'-hydroxyphenyl-4-benzoic acid, 3'-hydroxyphenyl-4-benzoic acid, 4'-hydroxyphenyl-3-benzoic acid and their alkyl , Alkoxy- or halogen-substituted products, and ester-forming derivatives thereof such as acylated products, ester derivatives, and acid halides. Among these, 4-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid are preferable from the viewpoint of easily adjusting the characteristics and melting point of the obtained liquid crystal polymer.

  Specific examples of the monomer that gives an aromatic dicarbonyl repeating unit include, for example, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1 Aromatic dicarboxylic acids such as 1,4-naphthalenedicarboxylic acid and 4,4′-dicarboxybiphenyl and their alkyl, alkoxy or halogen substituents, and ester-forming derivatives such as ester derivatives and acid halides thereof. . Among these, terephthalic acid and 2,6-naphthalenedicarboxylic acid are preferable because the mechanical properties, heat resistance, melting point temperature, and moldability of the obtained liquid crystal polymer can be easily adjusted to appropriate levels.

  Specific examples of the monomer that provides an aromatic dioxy repeating unit include, for example, hydroquinone, resorcin, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, Aromatic diols such as 4,4′-dihydroxybiphenyl, 3,3′-dihydroxybiphenyl, 3,4′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl ether and their alkyl, alkoxy or halogen substituents, and these And ester-forming derivatives such as acylated products. Among these, hydroquinone and 4,4'-dihydroxybiphenyl are preferable from the viewpoint of reactivity during polymerization, characteristics of the obtained liquid crystal polymer, and the like.

  Specific examples of the monomer that gives an aromatic aminooxy repeating unit include, for example, 4-aminophenol, 3-aminophenol, 4-amino-1-naphthol, 5-amino-1-naphthol, and 8-amino-2. -Aromatic hydroxyamines such as naphthol, 4-amino-4'-hydroxybiphenyl and their alkyl, alkoxy or halogen substitutions, and ester-forming derivatives such as their acylates.

  Specific examples of the monomer that gives an aromatic diamino repeating unit include aromatic diamines such as 1,4-diaminobenzene, 1,3-diaminobenzene, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, and the like. And alkyl, alkoxy or halogen substitution products thereof, and amide-forming derivatives thereof such as acylated products thereof.

  Specific examples of the monomer that gives an aromatic aminocarbonyl repeating unit include aromatic aminocarboxylic acids such as 4-aminobenzoic acid, 3-aminobenzoic acid, and 6-amino-2-naphthoic acid, and alkyls thereof. , Alkoxy- or halogen-substituted products, and ester-forming derivatives thereof such as acylated products, ester derivatives, and acid halides.

  Specific examples of monomers that give aromatic oxydicarbonyl repeat units include hydroxy aromatic dicarboxylic acids such as 3-hydroxy-2,7-naphthalenedicarboxylic acid, 4-hydroxyisophthalic acid, and 5-hydroxyisophthalic acid. Examples include acids and their alkyl, alkoxy or halogen-substituted products, and ester-forming derivatives thereof such as acylated products, ester derivatives and acid halides thereof.

  Specific examples of the monomer that gives an aliphatic dioxy repeating unit include aliphatic diols such as ethylene glycol, 1,4-butanediol, 1,6-hexanediol, and acylated products thereof. In addition, polymers containing aliphatic dioxy repeating units such as polyethylene terephthalate and polybutylene terephthalate are converted into the above-mentioned aromatic oxycarboxylic acids, aromatic dicarboxylic acids, aromatic diols and their acylated products, ester derivatives, acid halides. A liquid crystal polymer containing an aliphatic dioxy repeating unit can also be obtained by reacting with the above.

  Specific examples of the monomer that gives the aliphatic dicarbonyl repeating unit include, for example, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, and tetradecane. Examples include diacid, fumaric acid, maleic acid, and hexahydroterephthalic acid.

  The liquid crystal polymer used in the present invention may contain a thioester bond as long as the object of the present invention is not impaired. Examples of the monomer that gives such a bond include mercapto aromatic carboxylic acid, aromatic dithiol, and hydroxy aromatic thiol. The amount of these monomers used is aromatic oxycarbonyl repeating unit, aromatic dicarbonyl repeating unit, aromatic dioxy repeating unit, aromatic aminooxy repeating unit, aromatic diamino repeating unit, aromatic aminocarbonyl repeating unit, It is preferably 10 mol% or less based on the total amount including the total amount of monomers that give the aromatic oxydicarbonyl repeating unit, aliphatic dioxy repeating unit, and aliphatic dicarbonyl repeating unit.

  Depending on the composition and composition ratio of the monomers and the sequence distribution of each repeating unit in the polymer, polymers that combine these repeating units may or may not form an anisotropic molten phase. The liquid crystal polymer used is limited to those forming an anisotropic melt phase.

Further, specific examples of the liquid crystal polymer that can be used in the present invention include a copolymer composed of repeating units given by the following combination of monomers.
1) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid copolymer 2) 4-hydroxybenzoic acid / terephthalic acid / 4,4′-dihydroxybiphenyl copolymer 3) 4-hydroxybenzoic acid / terephthalic acid / Isophthalic acid / 4,4′-dihydroxybiphenyl copolymer 4) 4-hydroxybenzoic acid / terephthalic acid / isophthalic acid / 4,4′-dihydroxybiphenyl / hydroquinone copolymer 5) 4-hydroxybenzoic acid / terephthalic acid / Hydroquinone copolymer 6) 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone copolymer 7) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4,4′-dihydroxybiphenyl Copolymer 8) 6-Hydroxy-2-naphthoic acid / terephthalic acid / 4,4'-dihydride Xibiphenyl copolymer 9) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone copolymer 10) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone / 4,4'-dihydroxybiphenyl copolymer 11) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / 4,4'-dihydroxybiphenyl copolymer 12) 4-hydroxybenzoic acid / terephthalic acid / 2 6-Naphthalenedicarboxylic acid / hydroquinone copolymer 13) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 14) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / 2,6 -Naphthalenedicarboxylic acid / hydroquinone copolymer 15) 4-hydroxy Benzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone / 4,4′-dihydroxybiphenyl copolymer 16) 4-hydroxybenzoic acid / terephthalic acid / 4-aminophenol copolymer 17) 6-hydroxy- 2-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 18) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 19) 4-hydroxybenzoic acid / Terephthalic acid / 4,4′-dihydroxybiphenyl / 4-aminophenol copolymer 20) 4-hydroxybenzoic acid / terephthalic acid / ethylene glycol copolymer 21) 4-hydroxybenzoic acid / terephthalic acid / 4,4′- Dihydroxybiphenyl / ethylene glycol copolymer 22) 4-hydroxy Benzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / ethylene glycol copolymer 23) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4,4′-dihydroxybiphenyl / ethylene Glycol copolymer 24) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / 4,4′-dihydroxybiphenyl copolymer.

  The liquid crystal polymer used in the present invention may be a blend resin obtained by blending two or more kinds of liquid crystal polymers. For example, the copolymer of the above 1) and the copolymers of the above 7), 9) and 14). And a blend of one or more copolymers selected from the group consisting of:

As the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, those containing one or both of the repeating units represented by the formulas (I) and (II) are preferably used.

［式中、Ａｒ_１およびＡｒ_２はそれぞれ２価の芳香族基を表す。］
ここで、「芳香族基」は、６員の単環または環数２の縮合環である芳香族基を示す。 As the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, those containing repeating units represented by formulas (I) to (IV) are preferably used.

[Wherein, Ar ₁ and Ar ₂ each represent a divalent aromatic group. ]
Here, the “aromatic group” refers to an aromatic group which is a 6-membered monocyclic ring or a condensed ring having 2 rings.

Ar ₁ and Ar ₂ are, independently of each other, more preferably at least one selected from the group consisting of an aromatic group represented by the following formula (1) ~ (4), Ar 1 has the formula It is particularly preferred that the aromatic group is represented by (1) and / or (4), and Ar ₂ is an aromatic group represented by formula (1) and / or (3).

［ｐおよびｑは、各繰返し単位の液晶ポリマー中での組成比（モル％）であり、以下の式を満たす；
９０≦ｐ＋ｑ≦１００、
２０≦ｐ≦８０および
２０≦ｑ≦８０］
ｐ＋ｑ＝１００モル％であることが好ましいが、本発明の目的を損なわない限り、他の繰返し単位をさらに含有してもよい。 As a preferred embodiment of the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, a liquid crystal polymer composed of the composition ratio of the following repeating units is exemplified.

[P and q are composition ratios (mol%) in the liquid crystal polymer of each repeating unit and satisfy the following formula;
90 ≦ p + q ≦ 100,
20 ≦ p ≦ 80 and 20 ≦ q ≦ 80]
It is preferable that p + q = 100 mol%, but other repeating units may be further contained as long as the object of the present invention is not impaired.

［ｐ、ｑ、ｒ、およびｓは、各繰返し単位の液晶ポリマー中での組成比（モル％）であり、以下の式を満たす；
６０≦ｐ＋ｑ≦７８、
０．０５≦ｑ≦３、
１１≦ｒ≦２０および
１１≦ｓ≦２０］
ｐ＋ｑ＋ｒ＋ｓ＝１００モル％であることが好ましいが、本発明の目的を損なわない限り、他の繰返し単位をさらに含有してもよい。 As a preferred embodiment of the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, a liquid crystal polymer constituted by the composition ratio of the following repeating units can be mentioned.

[P, q, r, and s are composition ratios (mol%) in the liquid crystal polymer of each repeating unit, and satisfy the following formula:
60 ≦ p + q ≦ 78,
0.05 ≦ q ≦ 3,
11 ≦ r ≦ 20 and 11 ≦ s ≦ 20]
Although it is preferable that p + q + r + s = 100 mol%, other repeating units may be further contained unless the object of the present invention is impaired.

［式中、ｐ、ｑ、ｒ、ｔおよびｕは、各繰返し単位の液晶ポリマー中での組成比（モル％）を示し、以下の条件を満たす：
２５≦ｐ≦４５、
２≦ｑ≦１０、
１０≦ｒ≦２０、
１０≦ｔ≦２０、
２０≦ｕ≦４０および
ｒ＞ｔ］
ｐ＋ｑ＋ｒ＋ｔ＋ｕ＝１００モル％であることが好ましいが、本発明の目的を損なわない限り、他の繰返し単位をさらに含有してもよい。 As a preferred embodiment of the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, a liquid crystal polymer constituted by the composition ratio of the following repeating units can be mentioned.

[Wherein p, q, r, t and u represent the composition ratio (mol%) of each repeating unit in the liquid crystal polymer, and satisfy the following conditions:
25 ≦ p ≦ 45,
2 ≦ q ≦ 10,
10 ≦ r ≦ 20,
10 ≦ t ≦ 20,
20 ≦ u ≦ 40 and r> t]
Although it is preferable that p + q + r + t + u = 100 mol%, other repeating units may be further contained unless the object of the present invention is impaired.

  Examples of the monomer component that gives other repeating units include the above-mentioned other aromatic hydroxycarboxylic acids, aromatic diols, aromatic dicarboxylic acids, or aromatic hydroxydicarboxylic acids, aromatic hydroxyamines, aromatic diamines, aromatics. Aromatic aminocarboxylic acid, aromatic mercaptocarboxylic acid, aromatic dithiol, aromatic mercaptophenol and the like.

  The proportion of repeating units given from these other monomer components is preferably 10 mol% or less in the entire repeating units.

  The crystal melting temperature of the liquid crystal polymer used in the present invention is not particularly limited, but is preferably 270 to 360 ° C.

  Hereafter, the manufacturing method of the liquid crystal polymer used for this invention is demonstrated.

  There is no particular limitation on the method for producing the liquid crystal polymer used in the present invention, and a known polycondensation method for forming an ester bond or an amide bond composed of the above-mentioned monomers, for example, a melt acidosis method or a slurry polymerization method is used. can do.

  The melt acidolysis method is a preferred method for use in the method for producing the liquid crystal polymer used in the present invention, and this method first heats the monomer to form a melt of the reactant, The reaction is continued to obtain a molten polymer. Note that a vacuum may be applied to facilitate removal of volatiles (for example, acetic acid, water, etc.) by-produced in the final stage of the condensation.

  The slurry polymerization method is a method of reacting in the presence of a heat exchange fluid, and the solid product is obtained in a state suspended in a heat exchange medium.

  In any case of the melt acidification method and the slurry polymerization method, the polymerizable monomer component used in producing the liquid crystal polymer is a modified form in which hydroxyl groups and / or amino groups are acylated at room temperature, that is, lower It can also be subjected to the reaction as an acylated product. The lower acyl group preferably has 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms. Particularly preferred is a method using an acetylated product of the monomer in the reaction.

  The acylated product of the monomer may be prepared by separately acylating and synthesized in advance, or it may be generated in the reaction system by adding an acylating agent such as acetic anhydride to the monomer during the production of the liquid crystal polymer. it can.

  In any case of the melt acidification method or the slurry polymerization method, a catalyst may be used as needed during the reaction.

  Specific examples of the catalyst include organotin compounds such as dialkyltin oxide (for example, dibutyltin oxide) and diaryltin oxide, organotitanium compounds such as titanium dioxide, antimony trioxide, alkoxytitanium silicate, and titanium alkoxide, alkali or alkali of carboxylic acid Examples thereof include gaseous acid catalysts such as earth metal salts (for example, potassium acetate), inorganic acid salts (for example, potassium sulfate), Lewis acids (for example, boron trifluoride), hydrogen halides (for example, hydrogen chloride), and the like.

  The ratio of the catalyst used is usually 1 to 1000 ppm, preferably 2 to 100 ppm, based on the total amount of monomers.

  The liquid crystal polymer obtained by the polycondensation reaction in this way is extracted from the polymerization reaction tank in a molten state, and then processed into a pellet, flake, or powder.

  The liquid crystal polymer in the form of pellets, flakes, or powders may be heat-treated in a substantially solid state under reduced pressure or in an inert gas atmosphere for the purpose of increasing molecular weight and improving heat resistance.

  The temperature of the heat treatment performed in the solid phase is not particularly limited as long as the liquid crystal polymer is not melted, but it is preferably 260 to 350 ° C, preferably 280 to 320 ° C.

  The liquid crystal polymer composition of one embodiment in the present invention contains the liquid crystal polymer and a plate-like filler (A) having a particle diameter of 1 to 8 μm. The liquid crystal polymer composition of the present invention may contain the plate-like filler (A) alone, that is, only the plate-like filler (A) as a filler component. ), Fibrous filler (C) and / or other fillers.

  In the present invention, the particle diameter is a median diameter D50 measured by a laser diffraction method.

  The particle size of the plate-like filler (A) used in the present invention is 1 to 8 μm, preferably 2 to 6 μm, more preferably 3 μm or more and less than 5 μm. If the particle size of the plate filler (A) is less than 1 μm, the mechanical strength tends to be insufficient, and if it exceeds 8 μm, the tracking fracture resistance tends to be reduced.

  The content of the plate filler (A) is 60 to 150 parts by weight, preferably 65 to 140 parts by weight, and more preferably 70 to 130 parts by weight with respect to 100 parts by weight of the liquid crystal polymer.

  If the content of the plate-like filler (A) is less than 60 parts by weight, the effect of improving the anisotropy of the molding shrinkage is insufficient, and if it exceeds 150 parts by weight, the melt viscosity increases, so the resin composition by melt kneading It becomes difficult to produce the object.

  The liquid crystal polymer composition according to another embodiment of the present invention contains a liquid crystal polymer, a plate-like filler (A), and a filler (B) having a particle diameter of 10 to 50 μm.

  By making the content of the filler (B) within a certain range in the weight ratio with the plate-like filler (A), the mechanical strength can be improved while maintaining the tracking fracture resistance and the thermal conductivity.

  The particle diameter of the filler (B) used for this invention is 10-50 micrometers, and 15-30 micrometers is preferable. If it is less than 10 μm, the mechanical strength is not improved, and if it exceeds 50 μm, the tracking destruction resistance is deteriorated.

  When the filler (B) is contained, the total content of the plate filler (A) and the filler (B) is preferably 60 to 150 parts by weight, and the plate filler (A) and the filler (B). The weight ratio (B / A) is 0.05 to 1.0.

  If the total content of the plate-like filler (A) and the filler (B) is less than 60 parts by weight, the effect of improving anisotropy is not sufficient, and if it exceeds 150 parts by weight, the melt viscosity increases, There exists a tendency for preparation of the resin composition by kneading to become difficult. When the filler (B) is contained, the total content of the plate-like filler (A) and the filler (B) is more preferably 65 to 140 parts by weight, still more preferably 70 to 130 parts by weight.

  When the weight ratio (B / A) exceeds 1.0, the tracking fracture resistance and thermal conductivity are lowered. The weight ratio (B / A) between the plate-like filler (A) and the filler (B) is more preferably 0.05 to 0.67, still more preferably 0.05 to 0.54.

  When the filler (B) is contained, the content of the filler (B) is the total content of the plate-like filler (A) and the filler (B) and the plate-like filler (A) and the filler (B). Although it will not specifically limit if it is the quantity which satisfy | fills a weight ratio (B / A), For example with respect to 100 weight part of liquid crystal polymers, it is more than 0 weight part 75 weight part or less, 5-60 weight part, 10-50 weight part etc. It may be.

  As the plate-like filler (A), electrically insulating fillers such as talc, mica, kaolin, clay, vermiculite, calcium silicate, aluminum silicate, feldspar powder, acid clay, rhodolite clay, sericite, sillimanite, bentonite, glass Flakes, slate powder, silicates such as silane, carbonates such as calcium carbonate, hum powder, barium carbonate, magnesium carbonate, dolomite, barite powder, precipitated calcium sulfate, calcined gypsum, sulfate such as barium sulfate, hydrated alumina, etc. Hydroxides, alumina, antimony oxide, magnesia, titanium oxide, zinc oxide, silica, silica sand, quartz, white carbon, diatomaceous earth oxides, sulfides such as molybdenum disulfide, and plate-like wollastonite It is done.

  Among these, talc is preferable from the viewpoint of excellent thermal conductivity of the liquid crystal polymer composition.

The filler (B) should just be a filler which is not a fibrous filler, for example, a plate-like filler and a granular filler can be used.
As a plate-like filler, what was described as an example of the above-mentioned plate-like filler (A) can be used.
Examples of the granular filler include granular inorganic fillers such as calcium carbonate, glass beads, barium sulfate, titanium oxide, calcium fluoride, and magnesium oxide.
As the filler (B), a plate-like filler is preferable, and talc is more preferable from the viewpoint of excellent thermal conductivity of the liquid crystal polymer composition.

  The liquid crystal polymer composition of still another embodiment of the present invention includes a liquid crystal polymer, a plate-like filler (A), a filler (B) that may be contained in a certain range as described above, and a fibrous filler. (C) is contained.

  The fibrous filler (C) used in the present invention preferably has a number average fiber diameter of 5 to 20 μm and an average aspect ratio of 5 to 30 in terms of improving mechanical strength.

  The average aspect ratio is an index representing the shape of the fibrous filler and is a ratio of the number average fiber length to the number average fiber diameter (number average fiber length / number average fiber diameter).

  When the fibrous filler (C) is contained, the mechanical strength can be improved while suppressing a decrease in the anisotropy of the molding shrinkage rate by keeping the content of the fibrous filler (C) within a certain range. it can.

  The content of the fibrous filler (C) in the liquid crystal polymer composition of the present invention is preferably 5 to 30 parts by weight and more preferably 10 to 30 parts by weight with respect to 100 parts by weight of the liquid crystal polymer. More preferably, it is 15 to 25 parts by weight.

  If the content of the fibrous filler (C) is less than 5 parts by weight, the mechanical strength is not improved, and if it exceeds 30 parts by weight, the anisotropy of the shrinkage rate is increased.

  The weight ratio [C / A or C / (A + B)] of the fibrous filler (C) to the sum of the plate-like filler (A) and, if necessary, the filler (B) is 0.05 to 0.47. It is preferable to be in the range of 0.10, more preferably in the range of 0.10 to 0.33.

  When the weight ratio [C / A or C / (A + B)] exceeds 0.47, the anisotropy of the molding shrinkage ratio decreases.

  When the fibrous filler (C) is included, it is preferably contained in an amount of 5 to 30 parts by weight with respect to 100 parts by weight of the liquid crystal polymer, and the fibrous filler (C) and the plate-like filler (A) and when necessary. The weight ratio [C / A or C / (A + B)] to the total of fillers (B) is 0.05 to 0.47.

  Examples of the fibrous filler (C) include glass fiber, milled glass, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, potassium titanate whisker, aluminum borate whisker, and wollastonite. Of these, glass fiber is preferred because of its excellent strength and easy availability.

  Further, the liquid crystal polymer composition of the present invention is a filler other than the above-mentioned plate-like filler (A), filler (B) and fibrous filler (C) within the range not impairing the object of the present invention (hereinafter referred to as other fillings). For example, a particulate inorganic filler having a particle diameter of less than 10 μm or 50 μm or more may be further contained.

  Examples of the granular inorganic filler include calcium carbonate, glass beads, barium sulfate, titanium oxide, calcium fluoride, and magnesium oxide.

The liquid crystal polymer composition of the present invention can contain other additives as long as the effects of the present invention are not impaired.
Examples of other additives include higher fatty acids, higher fatty acid esters, higher fatty acid amides, higher fatty acid metal salts (here, higher fatty acids are those having 10 to 25 carbon atoms), polysiloxanes, fluororesins, and the like. Examples include mold release improvers, colorants such as carbon black, dyes, and pigments, antioxidants, heat stabilizers, ultraviolet absorbers, antistatic agents, and surfactants.

  The content of these other additives is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the liquid crystal polymer. When the content of these other additives exceeds 10 parts by weight, the moldability tends to be lowered, and the thermal stability and tracking breakdown resistance performance tend to deteriorate.

  For those having an external lubricant effect such as higher fatty acid, higher fatty acid ester, higher fatty acid metal salt, and fluorocarbon surfactant, the liquid crystal polymer composition is preliminarily adhered to the surface of the pellet of the liquid crystal polymer composition. May be.

  Further, the liquid crystal polymer composition of the present invention may further contain other resin components as long as the object of the present invention is not impaired.

  Examples of other resin components include polyamide, polyester, polyacetal, polyphenylene ether, and modified products thereof, and thermoplastic resins such as polysulfone, polyethersulfone, polyetherimide, and polyamideimide, phenol resin, epoxy resin, and polyimide resin. And other thermosetting resins.

  Other resin components can be contained alone or in combination of two or more. The content of other resin components is not particularly limited, and may be appropriately determined according to the use and purpose of the liquid crystal polymer composition. Typically, it is added in a range where the total content of other resins with respect to 100 parts by weight of the liquid crystal polymer is 0.1 to 100 parts by weight, particularly 0.1 to 80 parts by weight.

  The plate-like filler (A), filler (B) and fibrous filler (C), and other fillers, other additives, other resin components, etc. are added to the liquid crystal polymer, and Banbury mixer, kneader, uniaxial Alternatively, using a twin screw extruder or the like, a liquid crystal polymer composition can be obtained by melt-kneading from near the crystal melting temperature of the liquid crystal polymer under a temperature condition of crystal melting temperature + 30 ° C.

  In the melt-kneading, the plate-like filler (A) may be provided as it is, but may be provided as a compressed filler in order to increase the apparent specific gravity and improve the operability.

  The apparent specific gravity (JIS-K5101) of the filler obtained by compressing the plate filler (A) is preferably 0.3 to 0.45 g / ml, and more preferably 0.35 to 0.40 g / ml. preferable.

The plate-like filler (A) can be compressed by, for example, a spray drying method, a compression extrusion method, or a roll press process.
Examples of the shape of the secondary particles of the filler obtained by compressing the plate filler (A) include granules, spheres, and flakes.

  The liquid crystal polymer composition of the present invention thus obtained can be formed into a molded product by a known molding method such as injection molding or extrusion molding depending on the shape of the target part.

  The liquid crystal polymer composition of the present invention can be preferably used as a molding material for molded products such as switches, relays, connectors, chips, optical pickups, inverter transformers, coil bobbins, sensors, antennas and substrates.

  The liquid crystal polymer composition of the present invention has an advantage that the molded article constituted therefrom has a comparative tracking index (CTI) based on ASTM D3638-12 of 250 V or more, preferably 275 V or more, and is excellent in resistance to tracking destruction.

The liquid crystal polymer composition of the present invention has a flow direction when a molten resin composition is filled in a mold at the time of molding of a molded product composed thereof, and a ratio of shrinkage rate when solidified in a direction perpendicular thereto Has the advantage of being small.
Specifically, the shrinkage ratio (TD / MD) by dividing the molding shrinkage ratio (TD) in the perpendicular direction by the molding shrinkage ratio (MD) in the flow direction is preferably 1.0 to 3.0. Preferably it is 1.0-2.5, and it can be set as a comparatively isotropic molded article in which the anisotropy of the molding shrinkage rate is relaxed. Note that the closer the shrinkage ratio is to 1.0, the more isotropic.

  The liquid crystal polymer composition of the present invention preferably has a heat conductivity in the flow direction when the mold is filled with the molten resin composition at the time of molding, which is measured by a laser flash method, with respect to a molded article composed of the liquid crystal polymer composition. .8 W / m · K or more, more preferably 2.0 W / m · K or more, and excellent thermal conductivity.

The liquid crystal polymer composition of the present invention has a melt viscosity by a capillograph at the crystal melting temperature of the liquid crystal polymer + 20 ° C. (when the crystal melting temperature is higher than 300 ° C.) or the crystal melting temperature + 40 ° C. (when the crystal melting temperature is 300 ° C. or lower) (Shear rate 1000 sec ⁻¹ ) is preferably 40 to 100 Pa · s, more preferably 45 to 95 Pa · s.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to a following example at all.

  The measurement and evaluation of melt viscosity, load deflection temperature, tensile strength, bending strength and flexural modulus, Izod impact strength, comparative tracking index, molding shrinkage anisotropy, thermal conductivity and crystal melting temperature are as follows. It carried out by the method of description.

(1) Melt viscosity With a melt viscosity measuring device (Capillograph 1D manufactured by Toyo Seiki Co., Ltd.), the liquid crystal polymer of the synthesis example was 0.7 mmφ × 10 mm, and the liquid crystal polymer compositions of Examples 1 to 13 and Comparative Examples 1 to 8 Was measured using a 1.0 mmφ × 10 mm capillary under a shear rate of 1000 sec ⁻¹ and 350 ° C. (320 ° C. for LCP-3 and Example 15).

(2) Deflection temperature under load (DTUL)
Using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., UH1000-110), cylinder setting temperature 350 ° C. (320 ° C. for Example 15), mold temperature 70 ° C., length 127 mm, width 12.7 mm, It was molded into a strip-shaped test piece having a thickness of 3.2 mm, and measured according to ASTM D648 at a load of 1.82 MPa and a heating rate of 2 ° C./min.

(3) Tensile strength ASTM No. 4 dumbbell test using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industry Co., Ltd.) at a cylinder set temperature of 350 ° C. (320 ° C. for Example 15) and a mold temperature of 70 ° C. A piece was molded and measured according to ASTM D638.

(4) Bending strength and flexural modulus Using the same test piece as that used for measuring the deflection temperature under load, the bending strength and the flexural modulus were measured in accordance with ASTM D790.

(5) Izod impact strength Using the same test piece as that used for measuring the deflection temperature under load, the center of the test piece was cut perpendicular to the length direction, and the length was 63.5 mm, the width was 12.7 mm, and the thickness was A strip-shaped test piece of 3.2 mm was obtained and measured according to ASTM D256.

(6) Comparative tracking index (CTI)
Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industry Co., Ltd.), a cylinder set temperature of 350 ° C. (320 ° C. for Example 15), a mold temperature of 70 ° C., and a 50 mmφ × 3.2 mm thick disc A mold specimen was prepared. In accordance with ASTM D3638-12, a 0.1% by weight ammonium chloride aqueous solution and a platinum electrode were used to determine an applied voltage (V: volt) at which tracking occurs on the test piece, and this value was used as a comparative tracking index (V). . In addition, it shows that it is excellent in tracking destruction-proof performance, so that a comparative tracking index | exponent is high.

(7) Anisotropy of Mold Shrinkage Ratio Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industry Co., Ltd.), a cylinder set temperature of 350 ° C. (320 ° C. for Example 15) and a mold temperature of 70 ° C. Then, a test piece was prepared using a flat plate test piece mold having a side of a film gate of 80 mm × 80 mm × 1 mm, and the length of each side of the molded product was measured with a tool microscope.
By dividing the difference between this measured value and the mold dimension at room temperature by the mold dimension, the mold shrinkage rate of each side is obtained, and the average value for the two sides in the resin flow direction is calculated as the mold shrinkage rate in the flow direction ( MD), an average value for two sides perpendicular to the resin flow direction was defined as a molding shrinkage ratio (TD) in the perpendicular direction.
Further, the shrinkage ratio (TD / MD) was determined by dividing the molding shrinkage ratio (TD) in the perpendicular direction by the molding shrinkage ratio (MD) in the flow direction.

(8) Thermal conductivity Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industry Co., Ltd.), cylinder setting temperature 350 ° C. (320 ° C. for Example 15), mold temperature 70 ° C., 12.7 mm A bar flow test piece (side gate, gate opening 125 mm × 0.5 mm) having a thickness of × 127 mm × 1 mm was prepared, and these were laminated to a thickness of 10 mm. As shown in FIG. 1, this laminate is cut out from the gate side with a line perpendicular to the long axis direction [flow direction (MD) when the molten resin composition is filled in the mold], and the thickness is 10 mm × 10 mm × 1 mm. A flat plate was obtained.
A thermal diffusivity obtained by applying a laser light absorbing spray (Fine Chemical Japan Co., Ltd., Black Guard Spray FC-153) to the surface of the 10 mm × 10 mm surface of this flat plate as a thermal conductivity evaluation sample by a laser flash method. Was measured (manufactured by Netzsch, Xe flash analyzer LFA467 HyperFlash).
Specific heat was measured with a differential scanning calorimeter (Exstar 6000 manufactured by Seiko Instruments Inc.), and specific gravity was measured with an electronic hydrometer (Mirage Trading SD-200L).
The thermal conductivity was obtained from the product of thermal diffusivity, specific heat and specific gravity.

(9) Crystal melting temperature Using an Exstar 6000 manufactured by Seiko Instruments Inc. as a differential scanning calorimeter, the endothermic peak temperature (Tm1) observed when measured at room temperature to 20 ° C./min. Hold at 20-50 ° C elevated temperature for 10 minutes. Next, the sample is cooled to room temperature under a temperature-decreasing condition of 20 ° C./min. The temperature at the top of the exothermic peak observed at that time is set as the crystallization temperature (Tc) of the liquid crystal polymer, and again 20 ° C./min. An endothermic peak when measured under temperature rising conditions was observed, and the temperature showing the peak top was defined as the crystal melting temperature (Tm) of the liquid crystal polymer.

  Hereinafter, synthesis examples of liquid crystal polymers used in Examples and Comparative Examples are described. The abbreviations of the compounds in the synthesis examples are as follows.

[Monomers used for liquid crystal polymer synthesis]
POB: 4-hydroxybenzoic acid BON6: 6-hydroxy-2-naphthoic acid HQ: hydroquinone BP: 4,4'-dihydroxybiphenyl TPA: terephthalic acid NDA: 2,6-naphthalenedicarboxylic acid

[Synthesis Example 1 (LCP-1)]
In a reaction vessel equipped with a stirrer with a torque meter and a distillation pipe, POB: 323.2 g (36 mol%), BON 6: 48.9 g (4 mol%), BP: 169.4 g (14 mol%), HQ : 114.5 g (16 mol%) and TPA: 323.9 g (30 mol%), and 1.03 times mol acetic anhydride with respect to the amount of hydroxyl groups (mol) of all monomers were charged under the following conditions: Deacetic acid polymerization was performed.

  The temperature was raised from room temperature to 145 ° C. over 1 hour under a nitrogen gas atmosphere, and maintained at 145 ° C. for 30 minutes. Next, the temperature was raised to 350 ° C. over 7 hours while distilling off the acetic acid produced as a by-product, and then the pressure was reduced to 5 mmHg over 80 minutes. When the predetermined torque was exhibited, the polymerization reaction was terminated, the contents were taken out from the reaction vessel, and liquid crystal polyester resin pellets were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical. The obtained pellet had a crystal melting temperature (Tm) of 335 ° C. and a melt viscosity of 20 Pa · s.

[Synthesis Example 2 (LCP-2)]
POB: 641.9 g (71.5 mol%), BON 6: 30.6 g (2.5 mol%), HQ: 93.0 g (13 mol) %) And 182.7 g (13 mol%) of NDA, 1.03 times mol acetic anhydride with respect to the amount of hydroxyl groups (mol) of all monomers, and deacetic acid polymerization was carried out under the following conditions.

  The temperature was raised from room temperature to 145 ° C. over 1 hour under a nitrogen gas atmosphere, and maintained at 145 ° C. for 30 minutes. Next, the temperature was raised to 345 ° C. over 7 hours while acetic acid produced as a by-product was distilled off, and then the pressure was reduced to 10 mmHg over 80 minutes. When the predetermined torque was exhibited, the polymerization reaction was terminated, the contents were taken out from the reaction vessel, and liquid crystal polyester resin pellets were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical. The obtained pellet had a crystal melting temperature (Tm) of 321 ° C. and a melt viscosity of 23 Pa · s.

[Synthesis Example 3 (LCP-3)]
POB: 655.4 g (73 mol%) and BON6: 330.2 g (27 mol%) were charged into a reaction vessel equipped with a stirrer with a torque meter and a distillation pipe, and the hydroxyl amount (mol) of all monomers was further increased. On the other hand, 1.02 moles of acetic anhydride was charged and deacetic acid polymerization was performed under the following conditions.

  The temperature was raised from room temperature to 145 ° C. over 1 hour under a nitrogen gas atmosphere, and maintained at 145 ° C. for 30 minutes. Next, the temperature was raised to 320 ° C. over time while acetic acid produced as a by-product was distilled off, and then the pressure was reduced to 10 mmHg over 80 minutes. When the predetermined torque was exhibited, the polymerization reaction was terminated, the contents were taken out from the reaction vessel, and liquid crystal polyester resin pellets were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical. The obtained pellet had a crystal melting temperature (Tm) of 279 ° C. and a melt viscosity of 21 Pa · s.

The filler used in the following examples and comparative examples is shown.
<Plate filler>
Talc 1: Sumitomo Osaka Cement Co., Ltd., Fine Talc (particle size 4μm)
Talc 2: manufactured by Fuji Talc Co., Ltd., NK-64 (particle diameter 19 μm)
Talc 3: Nippon Talc Co., Ltd., D-800 (particle diameter 0.8 μm)
Mica: manufactured by Yamaguchi Mica, AB-25S (particle size 22 μm)
<Fibrous filler>
Glass fiber: manufactured by CPIC, ECS3010A (number average fiber diameter 10.5 μm, number average fiber length 3 mm)
<Granular filler>
CaF ₂ : Calcium fluoride particles (particle size: 26 μm) manufactured by Sumitomo Osaka Cement Co., Ltd.

[Examples 1-9, Comparative Examples 1-5]
Using LCP-1 as the liquid crystal polymer, talc, mica and CaF ₂ are blended so as to have the amounts shown in Table 1 with respect to 100 parts by weight of the liquid crystal polymer, and a twin-screw extruder (manufactured by Nippon Steel Works, TEX). The mixture melt-kneaded at 350 ° C. at −30α was pelletized to prepare a liquid crystal polymer composition.
For the liquid crystal polymer compositions of Examples and Comparative Examples, melt viscosity, load deflection temperature (DTUL), tensile strength, bending strength, bending elastic modulus, Izod impact strength, comparative tracking index, anisotropy of molding shrinkage, and heat conduction The rate was measured and the results are shown in Table 1.

[Examples 10 to 18, Comparative Examples 6 to 9]
LCP-1, LCP-2 and LCP-3 are used as the liquid crystal polymer, and talc, mica, CaF ₂ and glass fiber are blended so as to have the amounts shown in Table 2 with respect to 100 parts by weight of the liquid crystal polymer. What was melt-kneaded at 350 ° C. (320 ° C. for Example 15) with an extruder (manufactured by Nippon Steel Works, TEX-30α) was pelletized to prepare a liquid crystal polymer composition.
Similarly, for the liquid crystal polymer compositions of Examples and Comparative Examples, melt viscosity, load deflection temperature (DTUL), tensile strength, bending strength, bending elastic modulus, Izod impact strength, comparative tracking index, anisotropy of molding shrinkage rate The thermal conductivity was measured and the results are shown in Table 2.

  As shown in Table 1, in any of the liquid crystal polymer compositions of the present invention (Examples 1 to 9), the comparative tracking index is 250 V or more, and a good molding shrinkage ratio and thermal conductivity are obtained. In addition, the melt viscosity was moderate, and an excellent balance of tracking fracture resistance, molding shrinkage anisotropy, thermal conductivity and melt viscosity was exhibited.

On the other hand, as in Comparative Examples 1, 4, and 5, when out of the scope of the present invention, at least one of the comparative tracking index, the anisotropy of the molding shrinkage rate, or the thermal conductivity resulted in an undesirable result.
Comparative Example 2 has a comparative tracking index of 350 V, a molding shrinkage ratio of 1.5, and a thermal conductivity of 2.8 W / m · K. However, the melt viscosity is remarkably high at 167 Pa · s, and Izod impact strength. Was extremely low at 6 J / m, and was not suitable for use as a molded product.
Comparative Example 3 has a comparative tracking index of 300 V, a molding shrinkage ratio of 1.6, and a thermal conductivity of 2.4 W / m · K, but has a low tensile strength of 40 MPa and a bending strength of 48 MPa, and an Izod impact strength. Since it was as low as 8 J / m, it was not suitable for use as a molded product.

  Moreover, as shown in Table 2, all of the liquid crystal polymer compositions of the present invention (Examples 10 to 18) are excellent in tracking fracture resistance, anisotropy of molding shrinkage, thermal conductivity, and melt viscosity. In addition to showing a good balance, the inclusion of glass fibers also showed good mechanical properties.

On the other hand, when it was outside the scope of the present invention as in Comparative Examples 6 to 8, at least one of the comparative tracking index, the anisotropy of the molding shrinkage rate, or the thermal conductivity resulted in an undesirable result.
Comparative Example 9 has a comparative tracking index of 330 V, a molding shrinkage ratio of 2.5, and a thermal conductivity of 2.2 W / m · K, but a tensile strength of 45 MPa and a bending strength of 71 MPa. Even when fibers were contained, they were not suitable for use as molded articles.

Claims (15)

  A liquid crystal polymer composition containing 60 to 150 parts by weight of a plate-like filler (A) having a particle diameter of 1 to 8 μm and a comparative tracking index of 250 V or more with respect to 100 parts by weight of a liquid crystal polymer.   Furthermore, it contains a filler (B) having a particle diameter of 10 to 50 μm, and the total of the plate filler (A) and the filler (B) is 60 to 150 parts by weight with respect to 100 parts by weight of the liquid crystal polymer. The liquid crystal polymer composition according to claim 1, wherein a weight ratio (B / A) of the filler (A) to the filler (B) is 0.05 to 1.0.   Further, the fibrous filler (C) is contained in an amount of 5 to 30 parts by weight with respect to 100 parts by weight of the liquid crystal polymer, and the fibrous filler (C) and the plate-like filler (A) and, if necessary, the filler (B The liquid crystal polymer composition according to claim 1, wherein a weight ratio [C / A or C / (A + B)] to a total of 0.05 to 0.47.   The liquid crystal polymer composition according to claim 1, wherein the molding shrinkage ratio is 1.0 to 3.0.   The liquid crystal polymer composition according to any one of claims 1 to 4, wherein a thermal conductivity in a flow direction of the molten resin composition at the time of molding is 1.8 W / m · K or more.   The liquid crystal polymer composition according to any one of claims 1 to 5, wherein at least the plate-like filler (A) is talc.   The liquid crystal polymer composition according to any one of claims 1 to 6, wherein the fibrous filler (C) is a glass fiber.   The liquid crystal polymer composition according to claim 1, wherein the melt viscosity measured with a capillary rheometer is 45 to 100 Pa · s. The liquid crystal polymer composition according to claim 1, wherein the liquid crystal polymer contains one or both of the repeating units represented by formulas (I) and (II).

The liquid crystal polymer composition according to claim 9, wherein the liquid crystal polymer contains a repeating unit represented by formulas (I) to (IV).

[Wherein, Ar ₁ and Ar ₂ each represent a divalent aromatic group. ] The liquid crystal polymer composition according to claim 10, wherein Ar ₁ and Ar ₂ independently of each other include at least one selected from the group consisting of aromatic groups represented by formulas (1) to (4). .

The liquid crystal polymer composition according to claim 11, wherein Ar ₁ is an aromatic group represented by formula (4), and Ar ₂ is an aromatic group represented by formula (1). The liquid crystal polymer composition according to claim 11, wherein Ar ₁ is an aromatic group represented by formula (1) and Ar ₂ is an aromatic group represented by formula (1) and / or formula (3). object.   The molded article comprised from the liquid crystal polymer composition in any one of Claims 1-13.   The molded article according to claim 14, wherein the molded article is selected from the group consisting of a switch, a relay, a connector, an optical pickup, an inverter transformer, a coil bobbin, a sensor, an antenna, and a substrate.

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