Liquid crystal polymer composition

Abstract

To provide a liquid crystal polymer composition having improved adhesion.SOLUTION: A liquid crystal polymer composition contains 100 pts.mass of a liquid crystal polymer having a crystal melting temperature of 210-300°C and 1-100 pts.mass of an imine-modified polyolefin.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a liquid crystal polymer composition which contains a liquid crystal polymer and a specific modified polyolefin and which has significantly improved adhesive properties. [Background technology]

[0002] Thermotropic liquid crystal polymers (hereinafter referred to as liquid crystal polymers or LCPs) are excellent in mechanical properties such as heat resistance and rigidity, chemical resistance, dimensional accuracy, dielectric properties, etc., and therefore their use is expanding not only in molded products but also in various applications such as fibers and films. Furthermore, because of their excellent gas barrier properties, they are expected to be used as packaging materials.

[0003] However, when liquid crystal polymers are processed into films, although they exhibit high strength in the processing direction (MD), there is a problem in that the strength in the direction transverse to the processing direction (TD) is significantly reduced.

[0004] On the other hand, polyolefins such as polypropylene and polyethylene, which have been widely used as packaging materials, have an excellent processability into films, but have a problem of poor gas barrier properties.

[0005] In order to improve the gas barrier properties of polyolefin films, it has been considered to laminate them with liquid crystal polymer films to form composite films. However, liquid crystal polymers have insufficient adhesive properties with other resins, particularly polyolefins, and special treatments have been required to form composite films.

[0006] For example, a composite film has been proposed in which a thermoplastic resin is laminated on one side of a liquid crystal polymer layer without an adhesive layer (adhesive) by surface treating the liquid crystal polymer layer with corona discharge or the like (Patent Document 1). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 4-135750 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the composite film described in Patent Document 1 requires surface treatment such as corona discharge, which makes the process complicated, and the adhesive strength is not sufficient. Therefore, there has been a demand for the development of a liquid crystal polymer having improved adhesiveness to other resins.

[0009] An object of the present invention is to provide a liquid crystal polymer composition having improved adhesiveness. Another object of the present invention is to provide a molded article made of the liquid crystal polymer composition, particularly a blow molded article using the liquid crystal polymer composition as an adhesive layer between a liquid crystal polymer and a polyolefin. [Means for solving the problem]

[0010] In view of the above problems, the present inventors conducted intensive research and discovered that by blending an imine-modified polyolefin with a liquid crystal polymer, a liquid crystal polymer composition with significantly improved adhesiveness can be obtained, thereby completing the present invention.

[0011] That is, the present invention includes the following preferred embodiments. [1] A liquid crystal polymer composition comprising 100 parts by mass of a liquid crystal polymer having a crystalline melting temperature of 210 to 300° C. and 1 to 100 parts by mass of an imine-modified polyolefin. [2] The liquid crystal polymer composition according to [1], wherein the liquid crystal polymer has a crystalline melting temperature of 215 to 250°C. [3] The liquid crystal polymer is represented by the formulas (I) to (IV) [ka] [In the formula, Ar1 and Ar2 each represent one or more divalent aromatic groups, and p, q, r and s each represent the composition ratio (mol %) of each repeating unit in the wholly aromatic liquid crystal polyester, and satisfy the following condition: 0.5≦p / q≦2.5 2 ≤ r ≤ 15, and 2≦s≦15] The liquid crystal polymer composition according to [1] or [2], which is a wholly aromatic liquid crystal polyester containing a repeating unit represented by the following formula: [4] In the repeating units represented by formulae (III) to (IV), Ar1 and Ar2 are each independently represented by formulae (1) to (4). [ka] The liquid crystal polymer composition according to [3], wherein each of the repeating units is one or more types selected from aromatic groups represented by the following formula: [5] The liquid crystal polymer composition according to any one of [1] to [4], wherein the imine-modified polyolefin is an imine-modified polyethylene. [6] A molded article made of the liquid crystal polymer composition according to any one of [1] to [5]. [7] A molded article having a structure in which a liquid crystal polymer layer (a) and a polyolefin layer (b) are laminated via an adhesive layer (c), the adhesive layer (c) being made of the liquid crystal polymer composition according to any one of [1] to [5]. [8] The molded article according to [7], wherein the polyolefin layer (b) is a polyethylene layer or a polypropylene layer. [9] The molded article according to [7] or [8], which is a multilayer blow molded article. Effect of the Invention

[0012] The liquid crystal polymer composition of the present invention is not only used as a general molding material, but also is preferably used as an adhesive layer for blow molded products and laminated films due to its excellent adhesiveness. In addition, the liquid crystal polymer composition of the present invention is particularly preferably used as an adhesive material for liquid crystal polymers and polyolefins. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The liquid crystal polymer used in the liquid crystal polymer composition of the present invention is a wholly aromatic liquid crystal polyester or wholly aromatic liquid crystal polyester amide which forms an anisotropic molten phase and is called a thermotropic liquid crystal polymer by those skilled in the art.

[0014] The anisotropic melt phase properties of the liquid crystal polymer can be confirmed by conventional polarimetry using cross polarizers, ie, by observing a sample placed on a hot stage under a nitrogen atmosphere.

[0015] Examples of the repeating units constituting the liquid crystal polymer used in the present invention include aromatic oxycarbonyl repeating units, aromatic dicarbonyl repeating units, aromatic dioxy repeating units, aromatic aminooxy repeating units, aromatic diamino repeating units, aromatic aminocarbonyl repeating units, and combinations thereof.

[0016] Specific examples of monomers that provide aromatic oxycarbonyl repeating units include aromatic hydroxycarboxylic acids such as 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 the like, as well as their alkyl, alkoxy, or halogen-substituted derivatives, and their acylated derivatives, ester derivatives, acid halides, and other ester-forming derivatives. Among these, 4-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid are preferred because they are easy to adjust the mechanical properties, heat resistance, crystal melting temperature, and moldability of the resulting liquid crystal polymer to appropriate levels.

[0017] Specific examples of monomers that provide aromatic dicarbonyl repeating units include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, and 4,4'-dicarboxybiphenyl, as well as their alkyl, alkoxy, or halogen-substituted derivatives, and their ester-forming derivatives such as ester derivatives and acid halides. Among these, terephthalic acid and 2,6-naphthalenedicarboxylic acid are preferred because they are easy to adjust the mechanical properties, heat resistance, crystal melting temperature, and moldability of the resulting liquid crystal polymer to appropriate levels.

[0018] Specific examples of monomers that give aromatic dioxy repeating units include aromatic diols such as hydroquinone, resorcin, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, and their alkyl, alkoxy or halogen-substituted derivatives, as well as their acylated derivatives and other ester-forming derivatives. Among these, hydroquinone and 4,4'-dihydroxybiphenyl are preferred because they are easy to adjust the reactivity during polymerization, the mechanical properties of the resulting liquid crystal polymer, heat resistance, crystal melting temperature, and moldability to appropriate levels.

[0019] Monomers which provide the aromatic aminooxy repeating unit, aromatic diamino repeating unit and aromatic aminocarbonyl repeating unit include aromatic hydroxyamines, aromatic diamines and aromatic aminocarboxylic acids.

[0020] The liquid crystal polymer used in the present invention may contain an aromatic oxydicarbonyl repeating unit, an aliphatic dihydroxy repeating unit, an aliphatic dicarbonyl repeating unit, or a thioester bond, as long as the object of the present invention is not impaired. Examples of monomers that give thioester bonds include mercapto aromatic carboxylic acids, aromatic dithiols, and hydroxy aromatic thiols. The amount of these monomers used is preferably 10 mol% or less based on the total amount of the monomers that give aromatic oxycarbonyl repeating units, aromatic dicarbonyl repeating units, aromatic dioxy repeating units, aromatic aminooxy repeating units, aromatic diamino repeating units, and aromatic aminocarbonyl repeating units.

[0021] Among copolymers combining these repeating units, some form an anisotropic molten phase and some do not, depending on the monomer composition and composition ratio, and the sequence distribution of each repeating unit in the copolymer. However, the liquid crystal polymer used in the present invention is limited to copolymers that form an anisotropic molten phase.

[0022] The liquid crystal polymer used in the present invention may be a blend of two or more liquid crystal polymers.

[0023] The liquid crystal polymer used in the present invention has a crystalline melting temperature of 210 to 300°C, preferably 212 to 255°C, and more preferably 215 to 250°C, as measured by a differential scanning calorimeter.

[0024] When the crystalline melting temperature of the liquid crystal polymer is 210 to 300°C, the imine-modified polyolefin is easily dispersed in the composition, improving moldability into films, sheets, bottles, etc., and also making it easier to obtain adhesion between the liquid crystal polymer and other resins.

[0025] In the present specification and claims, the "crystalline melting temperature" is determined from the crystalline melting peak temperature measured at a heating rate of 20°C / min using a differential scanning calorimeter (hereinafter abbreviated as DSC). More specifically, after observing the endothermic peak temperature (Tm1) observed when a sample of a liquid crystal polymer is measured under a heating condition of 20°C / min from room temperature, the sample is held at a temperature 20 to 50°C higher than Tm1 for 10 minutes, and then cooled to room temperature under a cooling condition of 20°C / min, and then measured again under a heating condition of 20°C / min. The temperature showing the peak top is taken as the crystalline melting temperature of the liquid crystal polymer. For example, Exstar6000 manufactured by Seiko Instruments Inc. can be used as a measuring instrument.

[0026] As the liquid crystal polymer used in the present invention, a wholly aromatic liquid crystal polyester is preferably used, and a wholly aromatic liquid crystal polyester containing repeating units represented by formulae (I) to (IV) is more preferably used. [ka]

[0027] [In the formula, Ar1 and Ar2 each represent one or more divalent aromatic groups, and p, q, r and s each represent the composition ratio (mol %) of each repeating unit in the wholly aromatic liquid crystal polyester, and satisfy the following condition: 0.5≦p / q≦2.5 2 ≤ r ≤ 15, and 2≦s≦15.]

[0028] The molar ratio (p / q) of the composition ratio p (mol %) according to the above formula (I) to the composition ratio q (mol %) according to the above formula (II) is more preferably from 0.6 to 1.8, and further preferably from 0.8 to 1.6.

[0029] In the above-mentioned wholly aromatic liquid crystal polyesters which are suitably used, the total composition ratio of p and q is preferably from 70 to 96 mol %, and more preferably from 76 to 90 mol %.

[0030] In the above-mentioned wholly aromatic liquid crystal polyesters which are preferably used, the composition ratio p in formula (I) and the composition ratio q in formula (II) are each preferably 32 to 54 mol %, more preferably 36 to 52 mol %.

[0031] In the wholly aromatic liquid crystal polyester preferably used in the present invention, by containing the repeating units represented by formula (I) and formula (II) at least in the above-mentioned molar ratio (p / q), and optionally in the above-mentioned total composition ratio of p and q and / or each of p and q in the above-mentioned composition ratio (mol %), a wholly aromatic liquid crystal polyester exhibiting a crystalline melting temperature of 250°C or less can be preferably obtained.

[0032] In the wholly aromatic liquid crystal polyester preferably used in the present invention, the composition ratio r of formula (III) and the composition ratio s of formula (IV) are each preferably 2 to 15 mol %, more preferably 5 to 12 mol %. r and s are preferably equimolar amounts.

[0033] In the above repeating units, for example, Ar1 (or Ar2) represents two or more kinds of divalent aromatic groups means that the wholly aromatic liquid crystal polyester contains two or more kinds of repeating units represented by formula (III) (or (IV)) according to the type of divalent aromatic group. In this case, the composition ratio r of formula (III) (or the composition ratio s of formula (IV)) represents the total composition ratio of two or more kinds of repeating units.

[0034] Specific examples of monomers which provide the repeating unit represented by formula (I) include 4-hydroxybenzoic acid and its ester-forming derivatives such as acylation products, ester derivatives and acid halides.

[0035] Specific examples of monomers which provide the repeating unit represented by formula (II) include 6-hydroxy-2-naphthoic acid and its ester-forming derivatives such as acylation products, ester derivatives and acid halides.

[0036] Specific examples of monomers that provide the repeating unit represented by formula (III) include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 4,4'-dicarboxybiphenyl, and the like, as well as alkyl, alkoxy, or halogen-substituted derivatives thereof, and ester-forming derivatives thereof such as ester derivatives and acid halides.

[0037] Specific examples of monomers that provide the repeating unit represented by formula (IV) include aromatic diols such as hydroquinone, resorcinol, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, and ester-forming derivatives thereof, such as alkyl, alkoxy or halogen substituted products, and acylated products thereof.

[0038] Among the wholly aromatic liquid crystal polyesters preferably used in the present invention, those in which Ar1 and Ar2 in the repeating units represented by formulae (III) and (IV) each independently contain one or more aromatic groups selected from the group consisting of the aromatic groups represented by formulae (1) to (4) are more preferably used. That is, the repeating units represented by formulae (III) to (IV) each independently contain one or more aromatic groups selected from the group consisting of the aromatic groups represented by formulae (1) to (4). [ka]

[0039] Among these, as the repeating unit represented by formula (III), it is particularly preferred to use aromatic groups represented by formulas (1) and (4), i.e., terephthalic acid and 2,6-naphthalenedicarboxylic acid and their ester-forming derivatives as monomers that give these repeating units, because it is easy to adjust the mechanical properties, heat resistance, crystalline melting temperature and molding processability of the resulting wholly aromatic liquid crystal polyester to appropriate levels.

[0040] As the repeating unit represented by formula (IV), it is particularly preferred to use aromatic groups represented by formulas (1) and (3), i.e., hydroquinone, 4,4'-dihydroxybiphenyl, and their ester-forming derivatives as monomers that give these repeating units, because this makes it easy to adjust the reactivity during polymerization and the mechanical properties, heat resistance, crystalline melting temperature, and molding processability of the resulting wholly aromatic liquid crystal polyester to appropriate levels.

[0041] In the above repeating units, for example, Ar1 (or Ar2) containing two or more aromatic groups means that the wholly aromatic liquid crystal polyester contains two or more types of repeating units represented by formula (III) (or (IV)) according to the type of divalent aromatic group. That is, in the repeating units represented by formulas (III) to (IV), Ar1 and Ar2 are preferably each independently one or two or more types of repeating units selected from the aromatic groups represented by formulas (1) to (4). In this case, the composition ratio r according to formula (III) (or the composition ratio s according to formula (IV)) represents the composition ratio of the two or more types of repeating units in total.

[0042] In the wholly aromatic liquid crystal polyester preferably used in the present invention, the total composition ratio of the repeating units [p+q+r+s] is preferably 100 mol %, but other repeating units may be further contained within a range that does not impair the object of the present invention.

[0043] Examples of monomers which provide other repeating units constituting the wholly aromatic liquid crystal polyester preferably used in the present invention include other aromatic hydroxycarboxylic acids, aromatic hydroxyamines, aromatic diamines, aromatic aminocarboxylic acids, aromatic hydroxydicarboxylic acids, aromatic mercaptocarboxylic acids, aromatic dithiols, aromatic mercaptophenols, and combinations thereof.

[0044] Specific examples of other aromatic hydroxycarboxylic acids include 3-hydroxybenzoic acid, 2-hydroxybenzoic 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 alkyl, alkoxy or halogen substituted derivatives thereof, as well as ester-forming derivatives thereof such as acylation products, ester derivatives and acid halides.

[0045] The total composition ratio of the repeating units provided by these other monomer components is preferably 10 mol % or less based on the total repeating units.

[0046] The method for producing the liquid crystal polymer used in the present invention will now be described.

[0047] The method for producing the liquid crystal polymer used in the present invention is not particularly limited, and any known polycondensation method for forming ester bonds or amide bonds from the combination of the above-mentioned monomers, such as a molten acidolysis method or a slurry polymerization method, can be used.

[0048] The melt acidolysis method is a preferred method for preparing the liquid crystal polymers used in the present invention, in which the monomers are first heated to form a melt of reactants, which is then reacted to obtain a molten polymer, and a vacuum may be applied to facilitate removal of volatile by-products (e.g., acetic acid, water, etc.) produced during the final stage of condensation.

[0049] A slurry polymerization process is a process in which the reaction is carried out in the presence of a heat exchange fluid, and a solid product is obtained in suspension in the heat exchange medium.

[0050] In both the molten acidolysis method and the slurry polymerization method, the polymerizable monomer components used in producing the liquid crystal polymer can be subjected to the reaction at room temperature in a modified form in which the hydroxyl group and / or amino group is acylated, that is, as a lower acylated product. The lower acyl group preferably has 2 to 5 carbon atoms, more preferably has 2 or 3 carbon atoms. Particularly preferred is a method in which an acetylated product of the monomer is used in the reaction.

[0051] The acylated monomer may be one which has been previously synthesized by separate acylation, or may be produced in the reaction system by adding an acylating agent such as acetic anhydride to the monomer during the production of the liquid crystal polymer.

[0052] In either the molten acidolysis method or the slurry polymerization method, a catalyst may be used during the reaction, if necessary.

[0053] Specific examples of catalysts include organotin compounds (dialkyltin oxides such as dibutyltin oxide, diaryltin oxides, etc.), titanium dioxide, antimony trioxide, organotitanium compounds (alkoxytitanium silicates, titanium alkoxides, etc.), alkali and alkaline earth metal salts of carboxylic acids (potassium acetate, sodium acetate, etc.), Lewis acids (BF3, etc.), gaseous acid catalysts such as hydrogen halides (HCl, etc.), and the like.

[0054] The catalyst is used in an amount of usually 1 to 1000 ppm, preferably 2 to 100 ppm, based on the total amount of monomers.

[0055] The liquid crystal polymer thus obtained through the polycondensation reaction is withdrawn in a molten state from the polymerization reaction vessel and then processed into pellets, flakes, or powder.

[0056] The imine-modified polyolefin used in the present invention can be obtained, for example, by grafting a polyimine compound having a plurality of imino groups to a polyolefin in the presence of a radical generator. Examples of commercially available products include Admer (registered trademark) IP AT3346 and AT2937 manufactured by Mitsui Chemicals, Inc. Two or more types of imine-modified polyolefins may be used in combination.

[0057] In the imine-modified polyolefin used in the present invention, examples of the polyolefin to be modified include polyethylene, polypropylene, ethylene-propylene copolymer, polymethylpentene, etc., of which polyethylene and polypropylene are preferred, and polyethylene is particularly preferred.

[0058] In the present invention, when imine-modified polyethylene is used as the imine-modified polyolefin, the polyethylene to be used as the raw material is not particularly limited, and examples thereof include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, etc. These may be used alone or in combination of two or more kinds.

[0059] Among these, linear low density polyethylene (LLDPE) is preferred from the viewpoint of processability of the resulting liquid crystal polymer composition.

[0060] In the present invention, when imine-modified polypropylene is used as the imine-modified polyolefin, the polypropylene used as the raw material is not particularly limited, and examples thereof include homopolypropylene, block polypropylene, random polypropylene, etc. These may be used alone or in combination of two or more kinds.

[0061] Among these, homopolypropylene is preferred from the viewpoint of processability of the resulting liquid crystal polymer composition.

[0062] In the liquid crystal polymer composition of the present invention, the proportion of the imine-modified polyolefin is 1 to 100 parts by mass relative to 100 parts by mass of the liquid crystal polymer, and from the viewpoint of easily exhibiting adhesiveness, is preferably 5 to 90 parts by mass, more preferably 10 to 85 parts by mass, even more preferably 20 to 80 parts by mass, and particularly preferably 40 to 70 parts by mass.

[0063] The liquid crystalline polymer composition of the present invention may contain, as an optional component, inorganic and / or organic fillers.

[0064] Specific examples of inorganic and / or organic fillers that may be contained in the liquid crystal polymer composition of the present invention include glass fibers, silica alumina fibers, alumina fibers, carbon fibers, potassium titanate fibers, aluminum borate fibers, aramid fibers, polyarylate fibers, polybenzimidazole fibers, talc, mica, graphite, wollastonite, dolomite, clay, glass flakes, glass beads, glass balloons, calcium carbonate, barium sulfate, titanium oxide, etc. These may be used alone or in combination of two or more.

[0065] Among these, talc is preferred because it has an excellent balance between physical properties and cost.

[0066] The inorganic and / or organic filler may be surface-treated. Examples of the surface treatment method include a method in which a surface treatment agent is adsorbed on the surface of the filler, and a method in which a surface treatment agent is added during kneading.

[0067] Examples of the surface treatment agent include reactive coupling agents such as silane coupling agents, titanate coupling agents, and borane coupling agents, and lubricants such as higher fatty acids, higher fatty acid esters, higher fatty acid metal salts, and fluorocarbon surfactants.

[0068] When an inorganic and / or organic filler is blended, the content thereof is preferably 1 to 150 parts by mass, and more preferably 10 to 100 parts by mass, per 100 parts by mass of the total amount of the liquid crystal polymer and the imine-modified polyolefin.

[0069] If the content of the inorganic and / or organic filler is less than 1 part by mass, it is difficult to obtain the effect of improving the mechanical strength and heat resistance of the liquid crystal polymer composition due to the inorganic and / or organic filler, and if it exceeds 150 parts by mass, the fluidity tends to decrease. In the present invention, it is preferable that the liquid crystal polymer composition does not contain an inorganic and / or organic filler.

[0070] In addition to the liquid crystal polymer and the imine-modified polyolefin, other additives and resin components may be added to the liquid crystal polymer composition of the present invention, provided that the object of the present invention is not impaired.

[0071] Specific examples of other additives include, for example, lubricants such as higher fatty acids, higher fatty acid esters, higher fatty acid amides, and higher fatty acid metal salts (here, higher fatty acids refer to those having 10 to 25 carbon atoms), release agents such as polysiloxanes and fluororesins, colorants such as dyes, pigments, and carbon black, flame retardants, antistatic agents, surfactants, nucleating agents such as talc, organic phosphates, and sorbitols, antiblocking agents, antioxidants such as phosphorus-based antioxidants, phenol-based antioxidants, and sulfur-based antioxidants, weather resistance agents, heat stabilizers, and neutralizing agents. These additives can be used alone or in combination of two or more.

[0072] When other additives are contained, the total amount thereof is preferably 0.01 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, based on 100 parts by mass of the total amount of the liquid crystal polymer and the imine-modified polyolefin.

[0073] If the total amount of other additives is less than 0.01 parts by mass, it is difficult for the additives to realize their functions, whereas if it exceeds 5 parts by mass, the thermal stability of the liquid crystal polymer composition during molding tends to deteriorate.

[0074] Furthermore, when additives such as lubricants, release agents, and antiblocking agents are used among the other additives, they may be added when preparing the liquid crystal polymer composition, or may be attached to the pellet surface of the liquid crystal polymer composition during molding.

[0075] Specific examples of other resin components include thermoplastic resins such as polyamide, polyester, polyacetal, polyphenylene ether and modified products thereof, polysulfone, polyethersulfone, polyetherimide, polyamideimide, etc., and thermosetting resins such as phenol resin, epoxy resin, polyimide resin, etc. These resin components may be used alone or in combination of two or more kinds.

[0076] When other resin components are contained, the content thereof is preferably 100 parts by mass or less, more preferably 80 parts by mass or less, based on 100 parts by mass of the total amount of the liquid crystal polymer and the imine-modified polyolefin. In the present invention, it is preferable that the liquid crystal polymer composition does not contain other additives and other resin components.

[0077] The liquid crystal polymer composition of the present invention can be obtained by blending the above liquid crystal polymer, imine-modified polyolefin, and, if desired, the above inorganic filler and / or organic filler, other additives, other resin components, etc. in a predetermined composition, and melt-kneading them using a Banbury mixer, a kneader, a single-screw or twin-screw extruder, etc. Alternatively, the liquid crystal polymer composition of the present invention can be obtained by dry-blending the liquid crystal polymer and imine-modified polyolefin, and melt-kneading them in a molding machine.

[0078] The liquid crystal polymer composition of the present invention can be processed into films, sheets, bottles, containers, packaging materials, and the like by known molding methods such as injection molding, extrusion molding, and blow molding.

[0079] Among these, injection molding, extrusion molding, and blow molding are preferred from the viewpoints of ease of molding, mass productivity, cost, and the like.

[0080] When injection molding is adopted, the injection molding machine used for injection molding is not particularly limited, and may be, for example, any of the mold clamping mechanism types such as direct pressure type (hydraulic type) and toggle type, and may be any of the injection types such as the screw type (screw pre-plasticizing type, in-line screw type, etc.) and the plunger type (single plunger type, plunger pre-plasticizing type, etc.).

[0081] The direction of the cylinder may be either horizontal or vertical, and the driving mechanism may be hydraulic, electric or a combination of both.

[0082] The optimum injection conditions can be selected depending on the size of the injection molding machine, the shape of the mold, and the number of pieces. The gate position and the number of gates can be selected depending on the type of injection molded product.

[0083] In addition to the above-mentioned normal injection molding method, the injection molding method also includes injection molding methods that apply, for example, insert molding, injection compression molding, two-color molding, sandwich molding, and gas-assisted molding.

[0084] When extrusion molding or blow molding is employed, the resin can be processed into films, sheets, containers, pipes, fibers, etc., and may be a single or single-layer molded product, or may be a composite or multi-layered molded product having a part or layer made of another resin composition from the viewpoint of improving performance and reducing costs. Films, sheets, fibers, etc. can also be uniaxially or biaxially stretched. The obtained molded product may be subjected to secondary processing such as bending, vacuum forming, blow molding, and press molding, as necessary, to obtain a desired molded product.

[0085] The liquid crystal polymer composition of the present invention is used as a normal molding material, and is also suitable for use as an adhesive layer for blow molded products and laminated films due to its excellent adhesiveness. For example, a molded product having a structure in which a liquid crystal polymer layer (a) and a polyolefin layer (b) are laminated via an adhesive layer (c), and the adhesive layer (c) is the liquid crystal polymer composition of the present invention, is suitable. The polyolefin layer (b) is preferably a polyethylene layer or a polypropylene layer, and is particularly preferably a polyethylene layer. Such a molded product can be obtained by the above-mentioned molding method, but is preferably a multi-layer blow molded product obtained by blow molding.

[0086] Furthermore, the molded article made of the liquid crystal polymer composition of the present invention can be processed into a desired molded article by blow molding, which is suitable for molding hollow products such as bottles. Specific blow molding methods include direct blow molding, injection blow molding, free blow molding, etc. In particular, since the adhesiveness between the liquid crystal polymer layer and the polyolefin layer is improved, it is suitable for multi-layer blow molding by direct blow molding or injection blow molding.

[0087] The temperature conditions when molding the liquid crystal polymer composition of the present invention are preferably within the range of the crystalline melting temperature (210 to 300°C) of the liquid crystal polymer used to 350°C.

[0088] Molded articles made from the resin composition of the present invention are not particularly limited, but examples thereof include machine parts, electric and electronic parts, building and civil engineering materials, household and office supplies, furniture parts, and daily necessities, and molded articles such as containers are particularly useful.

[0089] Examples of electrical and electronic components include housings for copy machines, personal computers, printers, electronic musical instruments, home game consoles, and portable game consoles, as well as internal parts (connectors, switches, IC and LED housings, sockets, relays, resistors, condensers, coil bobbins, etc.).

[0090] Furthermore, since the liquid crystal polymer composition of the present invention has excellent adhesiveness to both liquid crystal polymers and resins such as polyolefins, it is also useful as an adhesive material and can be used, for example, as an adhesive layer in a laminate film.

[0091] Examples of resins that can be bonded to the liquid crystal polymer composition of the present invention include polyolefins such as polyethylene and polypropylene, polyesters, and polyamides. Among these, polyolefins are preferred, and polyethylene is more preferred.

[0092] The adhesiveness of the liquid crystal polymer composition of the present invention to the liquid crystal polymer can be evaluated by adhesive strength (tensile shear strength) according to JIS-K-7162. A composite having an adhesive strength of the liquid crystal polymer composition of the present invention to the liquid crystal polymer of usually 220 N or more, preferably 250 to 750 N, more preferably 280 to 600 N is suitable.

[0093] The adhesiveness of the liquid crystal polymer composition of the present invention to a polyolefin, when the polyolefin is polyethylene, can be evaluated by the adhesive strength (90 degree peel strength) according to JIS-C-6471. A composite having an adhesive strength of the liquid crystal polymer composition of the present invention to a polyolefin (e.g., LLDPE) of usually 5N or more, preferably 8 to 60N, more preferably 10 to 50N, is suitable.

[0094] The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. EXAMPLES

[0095] The crystal melting temperature and adhesiveness in the examples were measured by the methods described below.

[0096] <Measurement of Crystal Melting Temperature> The measurement was carried out using a differential scanning calorimeter (DSC) Exstar6000 manufactured by Seiko Instruments Inc. A liquid crystal polymer sample was measured under conditions of a temperature rise of 20°C / min from room temperature, and after observing the endothermic peak temperature (Tm1), 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 conditions of a temperature drop of 20°C / min, and then the endothermic peak was observed when measured again under conditions of a temperature rise of 20°C / min, and the temperature showing the peak top was taken as the crystalline melting temperature of the liquid crystal polymer.

[0097] Adhesion test with liquid crystal polymer Using an injection molding machine (UH1000-110 manufactured by Nissei Plastics Co., Ltd.), a liquid crystal polymer (the fully aromatic liquid crystal polyester resin described below) and an adhesive layer (the liquid crystal polymer composition obtained in the examples and comparative examples) were molded into barflow test pieces (length 150 mm x width 13 mm x thickness 0.8 mm) at a molding temperature of 250 ° C and a mold temperature of 40 ° C. The obtained barflow test pieces were stacked by 70 mm and placed in a heater at 250 ° C for 30 seconds to bond the barflow test pieces together. The adhesive strength (tensile shear strength) was measured according to JIS-K-7162 using an INSTRON5567 (a universal testing machine manufactured by Instron Japan Co., Ltd.).

[0098] <Adhesion test with linear low density polyethylene> Using an injection molding machine (UH1000-110 manufactured by Nissei Plastics Co., Ltd.), a bar flow test piece (length 150 mm x width 13 mm x thickness 0.8 mm) of linear low density polyethylene was molded at a molding temperature of 250 ° C and a mold temperature of 40 ° C. Also, a color plate test piece (90 mm x 55 mm x thickness 0.8 mm) of the adhesive layer was molded under the same conditions. The obtained bar flow and color plate were overlapped by 90 mm and placed in a heater at 250 ° C for 30 seconds to bond them. The adhesive strength (90 degree peel strength) was measured using an INSTRON5567 (a universal testing machine manufactured by Instron Japan Co., Ltd.) in accordance with JIS-C-6471.

[0099] In the examples and comparative examples, the following abbreviations represent the following compounds. LCP: Liquid crystal polymer LLDPE: Linear low density polyethylene POB: 4-hydroxybenzoic acid BON6: 6-hydroxy-2-naphthoic acid HQ: Hydroquinone TPA: Terephthalic acid

[0100] [Synthesis of LCP] In a reaction vessel equipped with a stirrer with a torque meter and a distillation tube, POB, BON6, HQ and TPA were charged in a total amount of 6.5 moles in the composition ratio shown in Table 1, and acetic anhydride was further charged in an amount of 1.03 times the moles of the hydroxyl groups (moles) of all monomers, and deacetic acid polymerization was carried out under the following conditions.

[0101] The temperature was raised from room temperature to 145°C in 1 hour under a nitrogen gas atmosphere, and the temperature was maintained for 30 minutes. Next, the temperature was raised to 330°C over 7 hours while distilling off the by-product acetic acid, and then the pressure was reduced to 10 mmHg over 80 minutes. The polymerization reaction was terminated when a predetermined torque was reached, and the contents of the reaction vessel were removed and pellets of a wholly aromatic liquid crystal polyester resin were obtained using a pulverizer. The amount of acetic acid distilled during polymerization was almost the theoretical value.

[0102] The crystalline melting temperature of the obtained LCP was 218°C as measured by DSC.

[0103] [Table 1]

[0104] In addition to the LCP synthesized in the above Synthesis Example, the materials used in the Examples and Comparative Examples are shown below. LLDPE: "Ultsex (registered trademark) 4570" manufactured by Prime Polymer Co., Ltd. Imine-modified polyethylene: "Admer (registered trademark) IP AT3346" manufactured by Mitsui Chemicals, Inc. Imine-modified polypropylene: "Admer (registered trademark) IP AT2937" manufactured by Mitsui Chemicals, Inc. Ethylene-glycidyl methacrylate copolymer: "Bondfast (registered trademark) E" manufactured by Sumitomo Chemical Co., Ltd.

[0105] Examples 1 to 3 and Comparative Examples 1 to 2 The synthesized LCP and the above materials were mixed to the contents shown in Table 2, and melt-kneaded at 250°C using a twin-screw extruder (TEX-30, manufactured by Nippon Steel Corporation) to obtain pellets of a liquid crystal polymer composition. A barflow test piece was prepared by the above method, and an adhesion test was performed. The results are shown in Table 2.

[0106] [Table 2]

[0107] As shown in Table 2, all of the liquid crystal polymer compositions of Examples 1 to 3 had improved adhesive strength and were excellent in adhesiveness to LCP and LLDPE.

[0108] In contrast, the liquid crystal polymer compositions of Comparative Examples 1 and 2 had poor adhesiveness and were not suitable as adhesive materials.

Claims

1. A liquid crystal polymer composition comprising 100 parts by mass of a liquid crystal polymer having a crystalline melting temperature of 210 to 300° C. and 20 to 80 parts by mass of an imine-modified polyolefin, the liquid crystal polymer being a wholly aromatic liquid crystal polyester.

2. 2. The liquid crystal polymer composition according to claim 1, wherein the liquid crystal polymer has a crystalline melting temperature of 215 to 250°C.

3. The liquid crystal polymer is represented by the formulas (I) to (IV): 【Chemistry 1】 [In the formula, Ar １ and Ar ２ each represents one or more kinds of divalent aromatic groups, and p, q, r and s each represent a composition ratio (mol %) of each repeating unit in the wholly aromatic liquid crystal polyester, and satisfy the following condition: 0.5≦p / q≦2.5 2≦r≦15, and 2≦s≦15] 3. The liquid crystal polymer composition according to claim 1, which is a wholly aromatic liquid crystal polyester comprising a repeating unit represented by the following formula:

4. The repeating units represented by formulae (III) to (IV) are Ar １ and Ar ２ are each independently represented by the formulas (1) to (4). 【Chemistry 2】 The liquid crystal polymer composition according to claim 3, wherein each repeating unit is one or more kinds of repeating units selected from aromatic groups represented by the following formula:

5. 5. The liquid crystal polymer composition according to claim 1, wherein the imine-modified polyolefin is an imine-modified polyethylene or an imine-modified polypropylene.

6. A molded article made of the liquid crystal polymer composition according to any one of claims 1 to 5.

7. A molded article having a structure in which a liquid crystal polymer layer (a) and a polyolefin layer (b) are laminated via an adhesive layer (c), the adhesive layer (c) being made of the liquid crystal polymer composition according to any one of claims 1 to 5.

8. The molded article according to claim 7, wherein the polyolefin layer (b) is a polyethylene layer or a polypropylene layer.

9. 9. The molded article according to claim 7 or 8, which is a multi-layer blow molded article.

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