JP5280281B2 - Liquid crystal polymer composition and molded article comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal polymer composition excellent especially in strength of welded part. <P>SOLUTION: Blending of a titanium dioxide-calcium carbonate composite particle, in which a titanium dioxide particle is supported on the surface of a calcium carbonate particle, with a liquid crystal polymer can improve strength of welded part without lowering other properties such as mechanical strengths, molding workability, etc. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a liquid crystal polymer composition, and more particularly to a liquid crystal polymer composition having excellent weld strength.

  Liquid crystal polymers are excellent in mechanical properties such as heat resistance and rigidity, chemical resistance, dimensional accuracy, etc., and their use is expanding not only for molded products but also for various applications such as fibers and films.

  In particular, in the information / communication field such as personal computers and mobile phones, there are many cases where a thin-walled portion is formed due to high integration of components, miniaturization, thinning, low profile, and the like. Therefore, in such a field, the amount of the liquid crystal polymer used is greatly increased by taking advantage of the characteristics that the other resins do not have such as excellent moldability, that is, good fluidity and no burrs.

  However, although liquid crystal polymers have excellent characteristics, weakness of the welded part and anisotropy of the molded product due to strong molecular orientation during molding are recognized as defects, and the strength of the welded part Various studies have been made on the improvement method.

  As a method for improving the strength of the weld portion, for example, a method of blending a fibrous filler such as aluminum borate whisker or titanium oxide whisker with a liquid crystal polyester resin is known (see Patent Documents 1 and 2). However, these whiskers are not only expensive but also insufficient in improving the strength of the weld.

  The inventors of the present invention have proposed a method for improving the strength of the welded portion by blending diatomaceous earth previously fired into the liquid crystal polymer (see Patent Document 3). According to this method, although the strength of the weld portion is improved to some extent, there is a problem that foaming occurs in the melt during injection purge during injection molding, and further improvement has been demanded.

JP-A-3-59067 JP-A-3-281656 JP 2008-111034 A

  An object of the present invention is to provide a liquid crystal polymer composition having excellent weld strength.

  As a result of intensive studies on improving the strength of the weld part of the liquid crystal polymer, the present inventors have found that titanium dioxide-calcium carbonate composite particles (hereinafter referred to as “titania-supported calcium carbonate”) in which titanium dioxide particles are supported on the surface of the calcium carbonate particles. It has been found that the strength of the weld portion can be improved without degrading other physical properties such as mechanical strength and molding processability by blending with the liquid crystal polymer, and the present invention has been completed.

  That is, in the first aspect, the present invention provides a liquid crystal polymer composition comprising a liquid crystal polymer and 0.1 to 200 parts by weight of titania-supported calcium carbonate with respect to 100 parts by weight of the liquid crystal polymer.

  In the first embodiment of the present invention, the “liquid crystal polymer composition” essentially includes a liquid crystal polymer and titania-supported calcium carbonate described below, and optionally, a filler, additive, liquid crystal other than titania-supported calcium carbonate. The composition which may contain other resin other than a polymer is meant.

  In the second aspect of the present invention, the liquid crystal polymer or the liquid crystal polymer composition is blended with 0.1 to 200 parts by weight of titania-supported calcium carbonate with respect to 100 parts by weight of the liquid crystal polymer. A method for improving the strength of a weld portion of a molded article of a polymer or liquid crystal polymer composition is provided.

  In the second aspect of the present invention, the “liquid crystal polymer composition” essentially includes a liquid crystal polymer described below, and further includes fillers and additives other than titania-supported calcium carbonate, and resins other than liquid crystal polymers. It means a composition containing one or more components selected from the above, and does not contain titania-carrying calcium carbonate.

  Hereinafter, unless otherwise specified in the specification, the “liquid crystal polymer composition” refers to the composition defined in the first embodiment, that is, a composition containing a liquid crystal polymer and titania-supported calcium carbonate.

FIG. 1 is a schematic diagram of creation of a test piece for measuring the bending strength of a weld. FIG. 2 shows the shape of the test piece for measuring the bending strength of the weld.

  In the present specification and claims, a weld portion is a portion where molten liquid crystal polymer or liquid crystal polymer composition flowing from two or more directions joins in a mold when liquid crystal polymer or liquid crystal polymer composition is molded. Means.

  The liquid crystal polymer used in the present invention is a polyester or polyester amide that forms an anisotropic melt phase, and is not particularly limited as long as it is called a thermotropic liquid crystal polyester or a thermotropic liquid crystal polyester amide by those skilled in the art.

  The property of the anisotropic molten phase 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 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.

  The liquid crystal polymer composed of each of these repeating units may or may not form an anisotropic molten phase depending on the constituent components, the composition ratio in the polymer, and the sequence distribution, but the liquid crystal used in the present invention. Polymers are limited to those that form an anisotropic melt phase.

  Specific examples of the monomer that gives an aromatic oxycarbonyl repeating unit include, for example, 4-hydroxybenzoic acid, metahydroxybenzoic acid, orthohydroxybenzoic 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, their alkyl, alkoxy Alternatively, halogen-substituted products, and ester-forming derivatives such as acylated products, ester derivatives, and acid halides can be used. In these, it is preferable from the point that the characteristic and melting | fusing point of a liquid crystal polymer from which parahydroxybenzoic acid and 6-hydroxy-2- naphthoic acid are obtained are easy to adjust.

  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, 2,6-naphthalenedicarboxylic acid is preferable because it easily adjusts the mechanical properties, heat resistance, melting point temperature, and moldability of the liquid crystal polymer to an appropriate level.

  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, 4,4′-dihydroxybiphenyl, 3,3′-dihydroxybiphenyl, 3,4′-dihydroxybiphenyl, aromatic diols such as 4,4′-dihydroxybiphenyl ether, alkyl, alkoxy or halogen substituents thereof, and And ester-forming derivatives such as acylated products. 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. -Aromatic amines such as naphthol and 4-amino-4'-hydroxybiphenyl, alkyl, alkoxy or halogen substituents thereof, and ester or amide-forming derivatives thereof such as 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 or amide-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. Polyesters containing aliphatic dioxy repeating units, such as polyethylene terephthalate and polybutylene terephthalate, are converted into the above aromatic oxycarboxylic acids, aromatic dicarboxylic acids, aromatic diols, aromatic hydroxyamines, aromatic diamines, aromatics. A liquid crystal polymer containing an aliphatic dioxy repeating unit can also be obtained by reacting with an aminocarboxylic acid, an aromatic oxydicarboxylic acid and an acylated product, an ester derivative, an acid halide or the like thereof.

  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, The amount is preferably 10 mol% or less based on the total amount of monomers giving the aromatic oxydicarbonyl repeating unit and the aliphatic dioxy repeating unit.

  As described above, the repeating unit contained in the liquid crystal polymer used in the present invention and the monomer that gives it have been described. As the liquid crystal polymer used in the present invention, a 4-oxybenzoyl repeating unit, which is an aromatic oxycarbonyl repeating unit, and It is more preferable to use one containing a 6-oxy-2-naphthoyl repeating unit.

Among the liquid crystal polymers containing 4-oxybenzoyl repeating units and / or 6-oxy-2-naphthoyl repeating units, preferred are, for example, copolymers comprising the following monomer constituent units.
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'-dihydroxybi Phenyl copolymer 9) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone copolymer 10) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / 4,4′-dihydroxy Biphenyl copolymer 11) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 12) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 13) 4 -Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 14) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone / 4,4 '-Dihydroxybiphenyl copolymer 15) 4-hydroxybenzoic acid / tere Taric acid / 4-aminophenol copolymer 16) 6-hydroxy-2-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 17) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 18) 4-hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / 4-aminophenol copolymer 19) 4-hydroxybenzoic acid / terephthalic acid / ethylene glycol copolymer 20) 4-hydroxybenzoic acid / terephthalic acid / 4,4′-dihydroxybiphenyl / ethylene glycol copolymer 21) 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / ethylene glycol copolymer 22 ) 4-Hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / Telef Taric acid / 4,4′-dihydroxybiphenyl / ethylene glycol copolymer.

  Of these, the copolymers 1), 9) and 13) are particularly preferably used as the liquid crystal polymer because of excellent molding processability and mechanical properties.

  As the liquid crystal polymer in the present invention, a blend of two or more liquid crystal polymers may be used for the purpose of improving fluidity during molding.

Hereinafter, a method for producing a liquid crystal polymer used in the present invention will be described.
The production method of the liquid crystal polymer used in the present invention is not particularly limited, 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 acidosis method, a slurry polymerization method, or the like is used. Can do.

  The melt acidosis method is a method in which a monomer is first heated to form a molten liquid of a reactant, and the reaction is continued to obtain a molten polymer, which is a preferred method for producing the liquid crystal polymer used in the present invention. It is. 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 both cases 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, that is, as a lower acylated product. It can also be used for the reaction. 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; antimony trioxide; titanium dioxide; organotitanium compounds such as alkoxytitanium 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 acid (for example, boron trifluoride); gaseous acid catalysts such as hydrogen halide (for example, hydrogen chloride).

  The ratio of the catalyst used is usually 10 to 1000 ppm, preferably 20 to 200 ppm, based on the monomer weight.

  The liquid crystal polymers obtained by such a polycondensation reaction are each extracted from the polymerization reaction tank in a molten state, and then processed into pellets, flakes, or powders.

  Liquid crystal polymers processed into pellets, flakes, or powders are in a substantially solid state under reduced pressure or in an inert gas atmosphere such as nitrogen or helium in order to increase molecular weight and improve heat resistance. Heat treatment may be performed.

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

  The liquid crystal polymer used in the present invention preferably has a crystal melting temperature (Tm) measured by a differential scanning calorimeter of 270 to 380 ° C., more preferably 280 to 340 ° C.

The crystal melting temperature (Tm) is measured by the method described below.
<Method for measuring crystal melting temperature>
After measuring the endothermic peak temperature (Tm1) observed when a liquid crystal polymer sample is measured at room temperature to 20 ° C./min, the sample is 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-decreasing condition of 20 ° C./min, and an endothermic peak was measured again when measured under a temperature-raising condition of 20 ° C./min. The temperature showing the peak top was the crystal melting temperature of the liquid crystal polymer. Temperature (Tm).

  The liquid crystal polymer thus obtained is blended with titania-supported calcium carbonate to obtain the liquid crystal polymer composition of the first aspect of the present invention.

  The titania-supporting calcium carbonate is a titanium dioxide-calcium carbonate composite particle in which titanium dioxide particles are directly supported on the surface of the synthetic calcium carbonate particles, and the particle size is 0.1 to 0.5 μm with respect to 100 parts by weight of the calcium carbonate particles. What carried 0.1-50 weight part of diameter titanium dioxide is preferable.

  The shape of calcium carbonate supporting titanium dioxide particles is not particularly limited, and cubic, columnar, or spindle-shaped ones can be used. However, since titanium dioxide is efficiently supported, the major axis is 1 to 15 μm and the minor axis is 0.00. Spindle-like calcium carbonate of 1 to 1 μm is preferred.

  As such titania-supporting calcium carbonate, for example, titanical (registered trademark) manufactured by Nippon Steel Mining Co., Ltd. is preferably used.

  The titania-supporting calcium carbonate preferably has an average particle size of 0.1 to 15 μm, more preferably 0.3 to 10 μm.

  In this invention, the compounding quantity of titania carrying | support calcium carbonate is 0.1-200 weight part with respect to 100 weight part of liquid crystal polymers, Preferably it is 0.1-150 weight part, More preferably, it is 1-100 weight part, Furthermore, Preferably it is 10-50 weight part.

  When the blending amount of titania-supporting calcium carbonate is less than 0.1 parts by weight, the effect of improving the strength of the weld degree cannot be obtained sufficiently, and when it exceeds 200 parts by weight, the melt viscosity tends to increase rapidly.

  The titania-supported calcium carbonate used in the present invention is added to the liquid crystal polymer, and melt kneaded at a temperature near the crystal melting temperature of the liquid crystal polymer or at the crystal melting temperature + 30 ° C. using a Banbury mixer, kneader, single screw or twin screw extruder. The liquid crystal polymer composition according to the first aspect of the present invention is used.

  The liquid crystal polymer composition of the first and second embodiments of the present invention may contain a filler other than titania-supported calcium carbonate for the purpose of improving mechanical properties. The shape of the filler other than titania-supported calcium carbonate is not particularly limited as long as the object of the present invention is not impaired, but one or more fillers selected from fibrous, plate-like, or powdery fillers may be used. preferable.

  Examples of fibrous fillers other than titania-supported calcium carbonate include glass fiber, milled glass, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, potassium titanate whisker, aluminum borate whisker, and wollastonite. Can be mentioned. Examples of plate-like or powdery fillers other than titania-supporting calcium carbonate include talc, mica, graphite, calcium carbonate, dolomite, clay, glass flakes, glass beads, barium sulfate, and titanium oxide.

  Among these, when glass fiber is used in combination with titania-supported calcium carbonate, the strength of the weld portion is remarkably improved and mechanical strength and molding processability are particularly preferable.

  When the filler other than titania-supported calcium carbonate is used in the liquid crystal polymer composition of the first and second embodiments of the present invention, the blending amount is 0.1 to 200 parts by weight with respect to 100 parts by weight of the liquid crystal polymer. Is more preferable, 0.1 to 150 parts by weight is more preferable, and 0.1 to 100 parts by weight is particularly preferable.

The liquid crystal polymer composition according to the first and second aspects of the present invention includes, in addition to titania-supported calcium carbonate and fillers other than titania-supported calcium carbonate, higher fatty acids and higher fatty acids as long as the effects of the present invention are not impaired. Mold release improvers such as esters, higher fatty acid amides, higher fatty acid metal salts, polysiloxanes, fluororesins; coloring agents such as dyes and pigments; antioxidants; thermal stabilizers; ultraviolet absorbers; antistatic agents; 1 type, or 2 or more types of additives, such as these, may be included in combination.
The compounding amount of these additives is preferably 0.01 to 5 parts by weight with respect to 100 parts by weight of the liquid crystal polymer.

  Those having an external lubricant effect such as higher fatty acid, higher fatty acid ester, higher fatty acid metal salt, and fluorocarbon surfactant may be previously adhered to the surface of liquid crystal polymer pellets during molding. Here, the higher fatty acid means one having 10 to 25 carbon atoms.

  Further, the liquid crystal polymer composition of the first and second embodiments of the present invention is a resin component other than the liquid crystal polymer, such as polyamide, polyester, polyphenylene sulfide, polyether ketone, within the range not impairing the object of the present invention. Combination of one or more of thermoplastic resins such as polycarbonate, polyphenylene ether, and modified products thereof, polysulfone, polyethersulfone, and polyetherimide, and thermosetting resins such as phenol resin, epoxy resin, and polyimide resin May be included.

  The blending amount of other resin components is not particularly limited, and may be determined as appropriate according to the use and purpose of the resin. Typically, the resin component is blended in an amount of 1 to 200 parts by weight, particularly 10 to 100 parts by weight, based on 100 parts by weight of the liquid crystal polymer of the present invention.

  Other than titania-supported calcium carbonate, fillers, additives, and other resins may be used in the same manner as titania-supported calcium carbonate using a Banbury mixer, kneader, uniaxial or twin screw extruder, etc. What is necessary is just to melt-knead at the vicinity thru | or crystal melting temperature +30 degreeC, and to mix | blend with a liquid crystal polymer.

  In the present invention, titania-supported calcium carbonate may be blended with a single liquid crystal polymer, or in advance, a fibrous, plate-like, or powdery filler other than titania-supported calcium carbonate, other resinous properties. The liquid crystal polymer composition according to the second aspect of the present invention prepared by blending various additives and the like may be blended.

  The liquid crystal polymer composition according to the first aspect of the present invention uses a bending test piece mold having a length of 64 mm, a width of 12.7 mm, and a thickness of 0.4 mm, and both the test piece molds have a weld line at the center. When the bending strength is measured according to JIS K7171, using the test piece obtained by filling the liquid crystal polymer composition from the side, the bending strength indicates 50 MPa or more.

  The present invention also provides a molded article having a weld part obtained by molding the liquid crystal polymer composition of the first aspect of the present invention.

  A molded article having a weld part obtained by using the liquid crystal polymer composition of the present invention blended with titania-supported calcium carbonate is significantly improved in the strength of the weld part and excellent in mechanical strength and moldability. It is particularly suitably used as an electric component, electronic component, mechanical component or the like that requires high strength of the weld portion.

  In the second aspect, the present invention provides a liquid crystal polymer or a liquid crystal polymer composition, wherein 0.1 to 200 parts by weight of titania-supported calcium carbonate is added to 100 parts by weight of the liquid crystal polymer or the liquid crystal polymer composition. Provided is a method for improving the strength of a weld portion of a molded product obtained by using the molded product.

  In the second aspect of the present invention, the liquid crystal polymer or liquid crystal polymer composition is blended such that the titania-supported calcium carbonate is 0.1 to 200 parts by weight with respect to 100 parts by weight of the liquid crystal polymer. Or the intensity | strength of the weld part of the molded article obtained using a liquid crystal polymer composition is improved significantly.

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

[Examples 1-4 and Comparative Examples 1-3]
In Examples and Comparative Examples, the liquid crystal polymer was LUE 1 as UENO LCP 2000 (Ueno Pharmaceutical Co., Ltd., 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone copolymer, crystal melting temperature. 325 ° C.) as LCP2, UENO LCP 2500 (Ueno Pharmaceutical Co., Ltd., 4-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid / terephthalic acid / hydroquinone copolymer, crystal melting temperature 330 ° C.) was used. .

<Example of liquid crystal polymer composition preparation>
For 100 parts by weight of the liquid crystal polymer, the types and amounts of fillers listed in Table 2 were used using a twin screw extruder PCM-30 (Ikegai Co., Ltd.), cylinder temperature, 330-320-320-310 ° C., screw The mixture was melt-kneaded under the condition of a rotation speed of 150 rpm to prepare pellets of the liquid crystal polymer composition.

<Example of specimen creation>
Using the pellet of the liquid crystal polymer composition obtained by the liquid crystal polymer composition preparation example, using the bending test piece mold having a thickness of 0.4 mm according to the molding conditions described in Table 1 below, the center part of the test piece In order to form a weld line, resin was filled from both sides of the test piece mold, and a test piece having a weld portion having the shape shown in FIG. 1 was prepared by injection molding.

<Measurement of bending strength of weld part>
According to JIS K7171, the weld part bending strength of the test piece obtained by the test piece preparation example was measured. Table 2 shows the measurement results of the weld portion bending strength of the liquid crystal polymer compositions of Examples 1 to 4 and Comparative Examples 1 to 3.

<Confirmation of foaming phenomenon>
During the injection molding for preparing the test piece, the foam generated in the melt during the injection purge is visually observed. ○). The results are shown in Table 2.

  As the filler, those containing only titania-supported calcium carbonate (Examples 1 and 2), and those using a combination of titania-supported calcium carbonate and glass fibers (Examples 3 and 4) have high bending strength at the weld part, Further, no foaming phenomenon occurred at the time of injection.

  On the other hand, those containing diatomaceous earth as a filler (Comparative Examples 1 and 2), although the bending strength of the weld portion is high, a foaming phenomenon occurs at the time of injection, and those containing only glass fiber as a filler (Comparison) In Example 3), although the foaming phenomenon did not occur, the bending strength of the weld portion was low.

＊１：日鉄鉱業株式会社製、チタニカル（登録商標）ＳＴ−２０（平均粒子径：３．３μｍ）
＊２：日東紡績株式会社製、ＣＳ ３Ｊ−４５４Ｓ
＊３：イーグルピッチャー社製、Ｃｅｌａｔｏｍ（登録商標）ＦＰ−２ （平均粒子径 １２．８μｍ）
＊４：イーグルピッチャー社製、Ｃｅｌａｔｏｍ（登録商標）ＦＷ−２０ （平均粒子径 ３３．０μｍ）

* 1: Made by Nippon Steel & Mining Co., Ltd., Titanical (registered trademark) ST-20 (average particle size: 3.3 μm)
* 2: Nitto Boseki Co., Ltd., CS 3J-454S
* 3: Celatom (registered trademark) FP-2 (average particle diameter: 12.8 μm) manufactured by Eagle Pitcher
* 4: Made by Eagle Pitcher, Celato (registered trademark) FW-20 (average particle size: 33.0 μm)

Claims (8)

  A liquid crystal polymer composition comprising a liquid crystal polymer and 0.1 to 200 parts by weight of titania-supported calcium carbonate with respect to 100 parts by weight of the liquid crystal polymer.   The liquid crystal polymer composition according to claim 1, comprising 0.1 to 100 parts by weight of titania-supported calcium carbonate with respect to 100 parts by weight of the liquid crystal polymer.   Furthermore, 0.1 to 200 parts by weight of 100 parts by weight of the liquid crystal polymer, including one or more fillers selected from fibrous, plate-like, or powdery fillers other than titania-supported calcium carbonate, Item 3. The liquid crystal polymer composition according to any one of Items 1 and 2.   The filler other than titania-supported calcium carbonate is selected from the group consisting of glass fiber, milled glass, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, potassium titanate whisker, aluminum borate whisker, and wollastonite. Fibrous filler, and a group consisting of talc, mica, graphite, calcium carbonate, dolomite, clay, glass flake, glass beads, barium sulfate, and titanium oxide selected from the group consisting of titanium oxide The liquid crystal polymer composition according to claim 3, wherein the liquid crystal polymer composition is one or more fillers selected.   The liquid crystal polymer composition according to claim 4, wherein the filler other than titania-supported calcium carbonate is glass fiber.   A bending test piece mold having a length of 64 mm, a width of 12.7 mm, and a thickness of 0.4 mm is used, and from both sides of the test piece mold so that a weld line can be formed in the center. The liquid crystal polymer composition according to any one of claims 1 to 5, wherein a weld bending strength measured according to JIS K7171 using a test piece obtained by filling the liquid crystal polymer composition is 50 MPa or more.   The molded article which has a weld part obtained by shape | molding the liquid-crystal polymer composition in any one of Claims 1-6.   A weld of a molded article of a liquid crystal polymer or a liquid crystal polymer composition, wherein 0.1 to 200 parts by weight of titania-supported calcium carbonate is blended with 100 parts by weight of a liquid crystal polymer or a liquid crystal polymer composition. Strength improvement method of the part.

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