JP6576754B2 - Liquid crystal polymer composition - Google Patents

Description

  The present invention relates to a liquid crystal polymer composition having excellent dielectric properties (dielectric constant, dielectric loss tangent) and vibration damping properties (damping properties), and improved flame retardancy.

  In modern society, the use of multimedia in everyday life and the use of ITS (Intelligent Transport Systems) such as ETC devices and GPS on toll roads are rapidly progressing. In order to cope with the explosive increase in information communication traffic accompanying this, the frequency of information transmission is increasing.

  As materials used for information communication devices with higher frequencies, engineering plastic materials with excellent dielectric properties in the high frequency band (especially gigahertz band) and excellent productivity and light weight are considered promising. It is expected to be applied as a casing or package of a device or electronic device, a dielectric device, or the like.

Among the engineering plastics described above, the thermotropic liquid crystal polyester resin (hereinafter abbreviated as liquid crystal polyester resin or LCP)
(1) Excellent dielectric characteristics such as a constant and low dielectric constant in the operating frequency band and a low dielectric loss tangent (tan δ).
(2) Excellent in various physical properties such as low expansion characteristics (environmental dimensional stability), heat resistance, flame resistance, mechanical properties such as rigidity,
(3) Excellent fluidity at the time of molding, and can easily process a molded product having a thin part and a fine part.
Therefore, it is a material that is particularly expected in high frequency applications.

  On the other hand, along with the rapid growth of information technology (IT), in the information / communication field, high integration, miniaturization, thinning, low profile, etc. of electric and electronic parts are progressing, and it is extremely less than 0.5mm. In many cases, a thin portion is formed, and even in such a portion (thin portion), good fluidity is required so that the resin is completely filled. In general, liquid crystalline polyester is superior in fluidity compared to other resins, but when such thinning is required, more severe flame retardancy is required along with further improvement in fluidity. It is coming.

  As a method for improving the flame retardancy of the liquid crystal polymer, there is a method of adding a halogen-based flame retardant (Patent Document 1), silicone (Patent Document 2), phosphorus compound (Patent Document 3), or red phosphorus (Patent Document 4). Proposed.

  Although the method of adding these substances has a certain effect of improving flame retardancy, the method of adding a halogen-based flame retardant or a phosphorus compound may corrode the mold due to the generation of gas. Also, the method of adding red phosphorus cannot be used for applications that require white, and the method of adding a phosphorus compound or silicone also has the problem of causing mold contamination and gas generation.

  On the other hand, a liquid crystal polyester resin composition for an optical pickup lens holder having a low thermal conductivity in which an inorganic spherical hollow body is blended with liquid crystal polyester has been proposed (Patent Document 5). However, the liquid crystal polyester composition containing such an inorganic spherical hollow body has not obtained the effect of improving flame retardancy.

JP-A-1-118567 JP 2000-239503 A JP-A-7-109406 JP 2000-154314 A Japanese Patent No. 4150015

  An object of the present invention is to provide a liquid crystal polymer composition which is excellent in dielectric properties (dielectric constant, dielectric loss tangent) and vibration damping properties (vibration suppression) and has improved flame retardancy.

As a result of intensive investigations on a liquid crystal polymer composition having both dielectric properties (dielectric constant, dielectric loss tangent), vibration damping properties (damping property) and flame retardancy, the inventors have determined that a glassy spherical hollow body has a predetermined quantitative ratio. Thus, it was found that the flame retardancy of the obtained liquid crystal polymer composition was remarkably improved by containing it in the liquid crystal polymer, and the present invention was completed.
That is, the present invention provides a liquid crystal polymer composition comprising 100 parts by weight of a liquid crystal polymer and 1 to 40 parts by weight of a glassy spherical hollow body and having a crystal melting temperature of less than 320 ° C.

  The liquid crystal polymer composition of the present invention has excellent vibration damping properties (damping properties) and dielectric properties, and is suitably used as a molding material having excellent flame retardancy.

  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 gas atmosphere.

  The liquid crystal polymer used in the present invention may be a kind of liquid crystal polyester resin or liquid crystal polyester amide resin, or a mixture of two or more liquid crystal polyester resins and / or liquid crystal polyester amide resins.

  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 all molecular chains are composed of aromatic groups 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 amino Examples thereof include a carbonyl repeating unit, an aromatic oxydicarbonyl repeating unit, and an aliphatic dioxy repeating unit.

  Specific examples of the monomer that gives an aromatic oxycarbonyl repeating unit include, for example, parahydroxybenzoic acid, metahydroxybenzoic acid, orthohydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, and 5-hydroxy-2-naphthoic acid. Acid, 3-hydroxy-2-naphthoic acid, 4'-hydroxyphenyl-4-benzoic acid, 3'-hydroxyphenyl-4-benzoic acid, 4'-hydroxyphenyl-3-benzoic acid, their alkyl, alkoxy or Halogen-substituted products, and ester-forming derivatives such as acylated products, ester derivatives, and acid halides thereof can be mentioned. Among these, parahydroxybenzoic acid and 6-hydroxy-2-naphthoic acid are preferable from the viewpoint that the characteristics of the obtained liquid crystal polymer and the crystal melting temperature can be easily adjusted.

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

  Specific examples of the monomer that gives 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, alkyl, alkoxy or halogen substituents thereof, And ester-forming derivatives such as acylated products thereof. Among these, hydroquinone and 4,4'-dihydroxybiphenyl are preferable from the viewpoint of reactivity during polymerization and characteristics of the obtained liquid crystal polymer.

  Specific examples of the monomer that gives an aromatic aminooxy repeating unit include, for example, p-aminophenol, m-aminophenol, 4-amino-1-naphthol, 5-amino-1-naphthol, and 8-amino-2. -Ester-forming derivatives such as aromatic hydroxyamines such as naphthol and 4-amino-4'-hydroxybiphenyl, alkyl, alkoxy or halogen substituents thereof, and acylated products thereof.

  Specific examples of the monomer that gives an aromatic diamino repeating unit include aromatic diamines such as p-phenylenediamine, m-phenylenediamine, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, and alkyls thereof. , Alkoxy- or halogen-substituted products, 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 p-aminobenzoic acid, m-aminobenzoic acid, 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 repeating units include hydroxy aromatic dicarboxylic acids such as 3-hydroxy-2,7-naphthalenedicarboxylic acid, 4-hydroxyisophthalic acid, and 5-hydroxyisophthalic acid. Examples include acids, alkyl, alkoxy or halogen-substituted products thereof, and ester-forming derivatives 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.

  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. These monomers are used in an aromatic oxycarbonyl repeating unit, an aromatic dicarbonyl repeating unit, an aromatic dioxy repeating unit, an aromatic aminooxy repeating unit, an aromatic diamino repeating unit, an aromatic aminocarbonyl repeating unit, The amount is preferably 10 mol% or less based on the total amount of the monomers giving the aromatic oxydicarbonyl repeating unit and the aliphatic dioxy 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 in the invention is limited to those forming an anisotropic molten phase.

  As the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, a liquid crystal polyester resin containing repeating units represented by the formulas (I) and (II) is excellent in terms of fluidity, mechanical properties and dielectric properties. Preferably used.

  In addition, the liquid crystal polymer used in the liquid crystal polymer composition of the present invention is composed of repeating units represented by the formulas (I) and (II) in terms of excellent fluidity, mechanical properties, and dielectric properties. A wholly aromatic liquid crystal polyester resin is preferably used.

  Furthermore, as the liquid crystal polymer used in the liquid crystal polymer composition of the present invention, all of the repeating units represented by the formulas (I) to (IV) are excellent in terms of fluidity, mechanical properties and dielectric properties. An aromatic liquid crystal polyester resin is 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。］

[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 each preferably one or more selected from the following aromatic groups (1) to (4) in terms of excellent fluidity, mechanical properties, and dielectric properties, and Ar ₁ is an aromatic group represented by the formula (1) and / or (4), it is particularly preferred Ar ₂ is an aromatic group represented by the formula (1) and / or (3).

  The liquid crystal polymer used in the liquid crystal polymer composition of the present invention includes a wholly aromatic liquid crystal polyester resin composed of repeating units represented by formulas (I) and (II), and formulas (I) to (I) It may be a mixture with a wholly aromatic liquid crystal polyester resin composed of repeating units represented by IV). In this case, it is preferable from the viewpoint of improving fluidity and heat resistance.

Specific examples of the preferred liquid crystal polymer used in the present invention include those composed of the following monomer structural units.
1) 4-hydroxybenzoic acid / 2-hydroxy-6-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) 4-hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / hydroquinone copolymer 7) 2-hydroxy-6-naphthoic acid / terephthalic acid / hydroquinone copolymer 8) 4- Hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / 4,4'-dihydride Roxybiphenyl copolymer 9) 2-hydroxy-6-naphthoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl copolymer 10) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / hydroquinone Copolymer 11) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / hydroquinone / 4,4'-dihydroxybiphenyl copolymer 12) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / 4,4'-dihydroxybiphenyl copolymer 13) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 14) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / Hydroquinone copolymer 15) 4-hydroxybenzoic acid / 2-hydroxy-6- Futheic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 16) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone / 4,4′-dihydroxybiphenyl copolymer 17) 4- Hydroxybenzoic acid / terephthalic acid / 4-aminophenol copolymer 18) 2-hydroxy-6-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 19) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoene Acid / terephthalic acid / 4-aminophenol copolymer 20) 4-hydroxybenzoic acid / terephthalic acid / 4,4′-dihydroxybiphenyl / 4-aminophenol copolymer 21) 4-hydroxybenzoic acid / terephthalic acid / ethylene Glycol copolymer 22) 4-hydroxybenzoic acid / terephthalic acid / , 4'-dihydroxybiphenyl / ethylene glycol copolymer 23) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / ethylene glycol copolymer 24) 4-hydroxybenzoic acid / 2-hydroxy-6 -Naphthoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / ethylene glycol copolymer 25) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / 4,4'-dihydroxybiphenyl copolymer.

  Among these, liquid crystal polymers comprising the monomer structural units of 10), 11) and 15) are preferred.

  The above liquid crystal polymers may be used alone or as a mixture of two or more liquid crystal polymers. In the case of a mixture of two or more kinds, a mixture of a liquid crystal polymer composed of the monomer constituent unit of 1) and any one of liquid crystal polymers composed of the monomer constituent units of 10), 11) and 15) In particular, it is preferable to use a mixture of a liquid crystal polymer composed of the monomer constituent unit 1) and a liquid crystal polymer composed of the monomer constituent unit 15).

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

  There is no particular limitation on the production method of 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 a combination of the above monomers, for example, a melt acididation method, a slurry polymerization method, or the like is used. Can do.

  The melt acidosis method is a preferred method for use in the method for producing a liquid crystal polymer used in the present invention, and this method first heats a monomer to form a molten liquid of a reactant, and then performs a reaction. Subsequently, a molten polymer is obtained. 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 organic tin compounds such as dialkyl tin oxide (eg dibutyl tin oxide) and diaryl tin oxide; organic titanium compounds such as titanium dioxide, antimony trioxide, alkoxy titanium silicate and titanium alkoxide; alkali or alkali of carboxylic acid Examples include earth metal salts (for example, potassium acetate); inorganic acid salts (for example, potassium sulfate); Lewis acids (for example, boron trifluoride); gaseous acid catalysts such as hydrogen halide (for example, hydrogen chloride).

  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.

  1 to 40 parts by weight, preferably 3 to 35 parts by weight, more preferably 4 to 30 parts by weight of a glassy spherical hollow body are contained per 100 parts by weight of the liquid crystal polymer thus obtained. The liquid crystal polymer composition of the invention is obtained. When the content of the glassy spherical hollow body in the liquid crystal polymer composition of the present invention is not less than the above lower limit, excellent flame retardancy can be obtained at the same time as obtaining excellent dielectric properties. When the content of the glassy spherical hollow body in the liquid crystal polymer composition of the present invention is not more than the above upper limit value, the mechanical strength is excellent.

  As the glassy spherical hollow body, a micro hollow body called a glass balloon made of a glass material is preferably used from the viewpoint of improving mechanical strength and flame retardancy.

  The average particle diameter of the glassy spherical hollow body is preferably 5 to 100 μm, more preferably 10 to 50 μm. The flame retardance of a liquid crystal polymer composition improves that the average particle diameter of a glass-like spherical hollow body is more than the said lower limit. When the average particle diameter of the glassy spherical hollow body is not more than the above upper limit value, the glassy spherical hollow body is hardly damaged. The particle diameter of the glassy spherical hollow body can be measured, for example, with a laser diffraction particle size distribution meter.

  The glass-like spherical hollow body does not necessarily have to be completely spherical, and may include an oval spherical shape. Generally, however, when the average aspect ratio exceeds 2, the glass-like spherical hollow body easily breaks. Since it increases, it is not preferable. Further, the volumetric hollow ratio of the glassy spherical hollow body is preferably 50% or more for decreasing the specific gravity and the relative dielectric constant, and 80% or less for suppressing the breakage rate of the glassy spherical hollow body. The volume hollow ratio can be obtained by 100 × (1−true specific gravity of micro hollow body / material specific gravity of micro hollow body).

  The glassy spherical hollow body used in the present invention can be produced by using a known method and, if necessary, can be obtained by adding a particle size selection step, but can also be obtained from the market. If necessary, the glassy spherical hollow body may be treated with a silane coupling agent or the like for the purpose of enhancing the uniform dispersibility in the liquid crystal polymer and the interface interaction.

  The liquid crystal polymer composition of the present invention may further contain a fibrous and / or plate-like inorganic filler as long as the object of the present invention is not impaired.

  Examples of the inorganic filler that may be further contained in the liquid crystal polymer composition of the present invention include, for example, glass fiber, milled glass, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, potassium titanate whisker, aluminum borate whisker, Examples thereof include one or more selected from the group consisting of wollastonite, mica, talc, graphite, calcium carbonate, dolomite, clay, glass flake, barium sulfate, and titanium oxide. Among these, glass fiber is preferred because the obtained liquid crystal polymer composition is excellent in mechanical strength and advantageous in terms of cost, and the obtained liquid crystal polymer composition is excellent in dimensional stability and in terms of cost. From the point of being advantageous, talc is preferable.

  The content of the fibrous and / or plate-like inorganic filler is preferably 0.5 to 50 parts by weight, and 1 to 40 parts by weight with respect to 100 parts by weight of the liquid crystal polymer from the viewpoint of fluidity and mechanical strength. More preferred is 5 to 30 parts by weight.

  The liquid crystal polymer composition of the present invention has other additives such as higher fatty acids, higher fatty acid esters, higher fatty acid amides, higher fatty acid metal salts (where higher fatty acids are carbon atoms within the range that does not impair the effects of the present invention. Release agents such as polysiloxanes and fluororesins; coloring agents such as dyes and pigments; antioxidants; thermal stabilizers; ultraviolet absorbers; antistatic agents; surfactants, etc. You may contain 1 type or 2 types or more selected from these in combination. Since the liquid crystal polymer composition of the present invention is excellent in flame retardancy, it is not necessary to contain a flame retardant, but it may contain a flame retardant as appropriate according to the application within a range not impairing the effects of the present invention. Examples of the flame retardant that may be contained in the liquid crystal polymer composition of the present invention include halogen compounds and phosphorus compounds.

  The content of these other additives is usually 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, with respect to 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 deteriorate and the thermal stability tends 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.

  Moreover, 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 glassy spherical hollow body, inorganic fillers other than the glassy spherical hollow body, other additives, and other resin components are added to the liquid crystal polymer, and a Banbury mixer, kneader, uniaxial or biaxial extruder The liquid crystal polymer composition can be obtained by melt-kneading at a temperature near the crystal melting temperature of the liquid crystal polymer or at the crystal melting temperature + 20 ° C.

  The liquid crystal polymer composition of the present invention thus obtained has a crystal melting temperature of less than 320 ° C., preferably 200 to 319 ° C., more preferably 210 to 318 ° C. When the crystal melting temperature is 320 ° C. or higher, the effect of improving flame retardancy is insufficient and the dielectric properties deteriorate.

  In the present specification, the liquid crystal polymer composition having excellent flame retardancy is a bar flow shape test piece of 170.0 mm × 12.5 mm × 0.8 mm, and is 48 hours at 23 ° C. and 50% relative humidity. After standing, it means that the evaluation based on the UL-94 standard is equivalent to V-0.

  The liquid crystal polymer composition of the present invention thus obtained is processed into a molded product such as an injection molded product, a film, a sheet, and a nonwoven fabric by a known molding method using an injection molding machine, an extruder or the like. . These molded articles are composed of the liquid crystal polymer of the present invention, that is, obtained by molding the liquid crystal polymer composition of the present invention.

  The liquid crystal polymer composition of the present invention is suitably used as a molding material for switches, relays, connectors, chips, optical pickups, inverter transformers, coil bobbins, antennas, substrates and the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.

<Liquid crystal polymer>
First, synthesis examples of liquid crystal polymers used in Examples and Comparative Examples will be described. Hereinafter, the abbreviations in the synthesis examples represent the following compounds.
[Monomer used for the synthesis of liquid crystal polymer]
POB: parahydroxybenzoic 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 tube, POB: 628.4 g (70 mol%), BON6: 24.5 g (2 mol%), HQ: 100.2 g (14 mol%) and NDA196 .7 g (14 mol%) was charged, and 1.03 times moles of acetic anhydride was charged 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 kept at that temperature 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 (LCP-1) pellets were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical.

[Synthesis Example 2 (LCP-2)]
POB: 655.4 g (73 mol%) and BON 6: 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 of all monomers (mol) ) Was added in an amount of 1.03 moles of acetic anhydride, 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 kept at that temperature 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 (LCP-2) pellets were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical.

[Synthesis Example 3 (LCP-3)]
Melting 17% by mass of the LCP-1 pellets obtained in Synthesis Example 1 and 83% by mass of the LCP-2 pellets obtained in Synthesis Example 2 with a twin screw extruder (manufactured by JSW, TEX-30) After kneading, the mixture was pelletized to obtain a mixture of LCP-1 and LCP-2 (LCP-3).

[Synthesis Example 4 (LCP-4)]
In a reaction vessel equipped with a stirrer with a torque meter and a distillation tube, POB: 349.3 g (40 mol%), BON 6: 476.0 g (40 mol%), HQ: 69.7 g (10 mol%) and TPA : 105.0 g (10 mol%) was charged, and 1.03 times moles of acetic anhydride was charged with respect to the amount of hydroxyl groups (mol) of all monomers, and deacetic acid polymerization was performed under the following conditions.

  The temperature was raised from room temperature to 145 ° C. over 1 hour in a nitrogen gas atmosphere, and the temperature was maintained 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 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 (LCP-4) were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical.

[Synthesis Example 5 (LCP-5)]
In a reaction vessel equipped with a stirrer with a torque meter and a distillation tube, POB: 386.0 g (43 mol%), BON 6: 183.5 g (15 mol%), HQ: 150.3 g (21 mol%) and TPA : 226.7 g (21 mol%) was charged, and 1.025 times moles of acetic anhydride was charged with respect to the amount of hydroxyl groups (mol) of all monomers, and deacetic acid polymerization was performed under the following conditions.

  The temperature was raised from room temperature to 145 ° C. over 1 hour in a nitrogen gas atmosphere, and the temperature was maintained 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 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 (LCP-5) pellets were obtained using a pulverizer. The amount of acetic acid distilled during the polymerization was almost as theoretical.

<Glass-like spherical hollow body>
S60HS manufactured by Sumitomo 3M Limited (average particle size 30.0μm, true specific gravity 0.60)

<Ceramic hollow body>
E-SPHERES SL125 (average particle size 80.0 μm) manufactured by Taiheiyo Cement Co., Ltd.

<Glass fiber>
Nittobo PF20E (average fiber length 24μm)

<talc>
NK-64 manufactured by Fuji Talc Co., Ltd. (average particle size 19.0 μm, water content 0.50% by weight)

[Example 1] (Reference Example)
Using LCP-1 as the liquid crystal polymer, 14 parts by weight of a glassy spherical hollow body is blended with 100 parts by weight of the liquid crystal polymer, and then melt-kneaded with a twin screw extruder (TEX-30 manufactured by JSW) is pelletized. A liquid crystal polymer composition was prepared.

  The pellets of the obtained liquid crystal polymer composition were measured for crystal melting temperature, flame retardancy (UL-94), dielectric constant, dielectric loss tangent, and vibration damping characteristics by the following methods. The results are shown in Table 3.

(1) Crystal melting temperature Using a differential scanning calorimeter (Exstar 6000 manufactured by Seiko Instruments Inc.), the endothermic peak temperature (Tm1) observed when the sample is measured from room temperature to 20 ° C./min is measured. Then, it was held at a temperature 20 to 50 ° C. higher than Tm1 for 10 minutes. Next, the sample was cooled to room temperature under a temperature drop condition of 20 ° C./min, and an endothermic peak was measured again when measured under a temperature rise condition of 20 ° C./min. The temperature showing the peak top was the crystal melting temperature (Tm ).

(2) Flame retardance The sample was a bar flow shape having a length of 170 mm, a width of 12.7 mm, and a thickness of 0.8 mm under the conditions shown in Table 1 using an injection molding machine (PS40 manufactured by Nissei Plastic Industry Co., Ltd.). It shape | molded into the test piece, and left still for 48 hours on the conditions of 23 degreeC and relative humidity 50%, Then, it evaluated based on UL-94 specification.

(3) Dielectric constant and dielectric loss tangent (tan δ)
The sample was molded into a stick-shaped test piece having a length of 85 mm, a width of 1.75 mm, and a thickness of 1.75 mm under the conditions described in Table 2 using an injection molding machine (PS40 manufactured by Nissei Plastic Industry Co., Ltd.) Using the specimen, the dielectric constant and dielectric loss tangent at 10 GHz were measured by a cavity resonator perturbation method with a vector network analyzer (manufactured by Agilent Technologies).

(4) Vibration damping characteristics A bar flow shape having a length of 170 mm, a width of 12.7 mm, and a thickness of 0.8 mm under the conditions shown in Table 2 using an injection molding machine (PS40 manufactured by Nissei Plastic Industry Co., Ltd.). A loss factor was calculated from the bending free vibration waveform of the bending vibration of the JIS G 0602 one-end fixed impact vibration method and evaluated. Since the reciprocal of the loss coefficient is proportional to the number of vibrations during vibration, the smaller the reciprocal of the loss coefficient, the faster the vibration is stopped (excellent vibration damping), and the larger the loss coefficient, the better the vibration damping.

[Examples 2 to 7 and Comparative Examples 1 to 9] (Example 7 is a reference example)
Liquid crystal polymer compositions were prepared in the same manner as in Example 1, except that the liquid crystal polymer, glassy spherical hollow body, glass fiber, talc and ceramic hollow body were blended in the proportions shown in Table 3.
The obtained liquid crystal polymer composition pellets were measured for crystal melting temperature, flame retardancy (UL-94), dielectric constant, dielectric loss tangent and vibration damping characteristics. The results are shown in Table 3.

〔３〕液晶ポリマーが、式（Ｉ）および式（ＩＩ）で表される繰返し単位から構成される全芳香族液晶ポリエステル樹脂である、〔１〕または〔２〕に記載の液晶ポリマー組成物。
〔４〕液晶ポリマーが、式（Ｉ）〜（ＩＶ）で表される繰返し単位から構成される全芳香族液晶ポリエステル樹脂である、〔１〕に記載の液晶ポリマー組成物。

［式中、Ａｒ _１ およびＡｒ _２ はそれぞれ２価の芳香族基を表す。］
〔５〕Ａｒ _１ およびＡｒ _２ がそれぞれ、下記の芳香族基（１）〜（４）から選択される１種以上である、〔４〕に記載の液晶ポリマー組成物。

〔６〕Ａｒ _１ が式（１）および／または（４）で表される芳香族基であり、Ａｒ _２ が式（１）および／または（３）で表される芳香族基である、〔５〕に記載の液晶ポリマー組成物。
〔７〕液晶ポリマーが、式（Ｉ）および式（ＩＩ）で表される繰返し単位から構成される全芳香族液晶ポリエステル樹脂と、式（Ｉ）〜（ＩＶ）で表される繰返し単位から構成される全芳香族液晶ポリエステル樹脂との混合物である、〔１〕に記載の液晶ポリマー組成物。
〔８〕ガラス状球状中空体がガラスバルーンである、〔１〕〜〔７〕の何れかに記載の液晶ポリマー組成物。
〔９〕液晶ポリマー１００重量部に対して、さらに繊維状および／または板状の無機充填材０．５〜５０重量部を含む、〔１〕〜〔８〕の何れかに記載の液晶ポリマー組成物。
〔１０〕繊維状および／または板状の無機充填材が、ガラス繊維およびタルクからなる群から選択される１種以上である、〔９〕に記載の液晶ポリマー組成物。
〔１１〕〔１〕〜〔１０〕の何れかに記載の液晶ポリマー組成物から構成される成形品。
〔１２〕成形品が、スイッチ、リレー、コネクタ、チップ、光ピックアップ、インバータトランス、コイルボビン、アンテナおよび基板からなる群から選択されるものである、〔１１〕に記載の成形品。
As shown in Table 3, the liquid crystal polymer compositions of Examples 1 to 7 have a flame retardancy evaluation (EL-94) of V-0 and are found to have high flame retardancy. At the same time, since the dielectric constant and the dielectric loss tangent (tan δ) are low and the loss factor is large, it is clear that the dielectric characteristics and the vibration damping properties are excellent.
On the other hand, some of the liquid crystal polymer compositions of Comparative Examples 1 to 9 have high dielectric properties and vibration damping properties, but all the liquid crystal polymer compositions have low flame retardancy.
Preferred embodiments of the present invention include:
[1] A liquid crystal polymer composition comprising 100 parts by weight of a liquid crystal polymer and 1 to 40 parts by weight of a glassy spherical hollow body and having a crystal melting temperature of less than 320 ° C.
[2] The liquid crystal polymer composition according to [1], wherein the liquid crystal polymer is a liquid crystal polyester resin containing repeating units represented by formulas (I) and (II).

[3] The liquid crystal polymer composition according to [1] or [2], wherein the liquid crystal polymer is a wholly aromatic liquid crystal polyester resin composed of repeating units represented by formulas (I) and (II).
[4] The liquid crystal polymer composition according to [1], wherein the liquid crystal polymer is a wholly aromatic liquid crystal polyester resin composed of repeating units represented by formulas (I) to (IV).

[Wherein, Ar ₁ and Ar ₂ each represent a divalent aromatic group. ]
[5] The liquid crystal polymer composition according to [4], wherein Ar ₁ and Ar ₂ are each one or more selected from the following aromatic groups (1) to (4).

[6] Ar ₁ is an aromatic group represented by the formula (1) and / or (4), and Ar ₂ is an aromatic group represented by the formula (1) and / or (3). [5] Liquid crystal polymer composition according to [5].
[7] The liquid crystal polymer is composed of a wholly aromatic liquid crystal polyester resin composed of repeating units represented by the formulas (I) and (II) and a repeating unit represented by the formulas (I) to (IV). The liquid crystal polymer composition according to [1], which is a mixture with a wholly aromatic liquid crystal polyester resin.
[8] The liquid crystal polymer composition according to any one of [1] to [7], wherein the glassy spherical hollow body is a glass balloon.
[9] The liquid crystal polymer composition according to any one of [1] to [8], further comprising 0.5 to 50 parts by weight of a fibrous and / or plate-like inorganic filler with respect to 100 parts by weight of the liquid crystal polymer. object.
[10] The liquid crystal polymer composition according to [9], wherein the fibrous and / or plate-like inorganic filler is at least one selected from the group consisting of glass fibers and talc.
[11] A molded article composed of the liquid crystal polymer composition according to any one of [1] to [10].
[12] The molded product according to [11], wherein the molded product is selected from the group consisting of a switch, a relay, a connector, a chip, an optical pickup, an inverter transformer, a coil bobbin, an antenna, and a substrate.

Claims (9)

A liquid crystal polymer composition comprising 100 parts by weight of a liquid crystal polymer and 5 to 40 parts by weight of a glassy spherical hollow body and having a crystal melting temperature of less than 320 ° C. ,
The liquid crystal polymer has the formula (I) and formula (II)

A wholly aromatic liquid crystal polyester resin composed of repeating units represented by:
Formulas (I) to (IV)

[Wherein Ar ₁ and Ar ₂ each represent a divalent aromatic group]
Wholly aromatic liquid crystalline polyester resin composed of repeating units represented by
A liquid crystal polymer composition which is a mixture of The liquid crystal polymer composition according to claim 1 , wherein Ar ₁ and Ar ₂ are each one or more selected from the following aromatic groups (1) to (4).

Wherein Ar ₁ is an aromatic group represented by the formula (1) and / or (4), an aromatic group Ar ₂ is represented by the formula (1) and / or (3), in claim 2 The liquid crystal polymer composition described. Glassy spherical hollow body is a glass balloon, a liquid crystal polymer composition according to any one of claims 1-3. The liquid crystal polymer composition according to any one of claims 1 to 4 , further comprising 0.5 to 50 parts by weight of a fibrous and / or plate-like inorganic filler with respect to 100 parts by weight of the liquid crystal polymer. The liquid crystal polymer composition according to claim 5 , wherein the fibrous and / or plate-like inorganic filler is at least one selected from the group consisting of glass fibers and talc. The liquid crystal polymer composition according to claim 1, which does not contain a flame retardant.   The molded article comprised from the liquid crystal polymer composition in any one of Claims 1-7.   The molded article according to claim 8, wherein the molded article is selected from the group consisting of a switch, a relay, a connector, a chip, an optical pickup, an inverter transformer, a coil bobbin, an antenna, and a substrate.