JP7461168B2 - Liquid crystal polymer composition - Google Patents

Description

The present invention relates to a liquid crystal polymer composition containing a liquid crystal polymer and a specific modified polyolefin, which has significantly improved adhesion.

Thermotropic liquid crystal polymers (hereinafter also referred to as liquid crystal polymers or LCP) have excellent mechanical properties such as heat resistance and rigidity, chemical resistance, dimensional accuracy, and dielectric properties, so they are used not only for molded products but also for fibers and Its use is expanding to various applications such as films. Furthermore, since it has excellent gas barrier properties, it is expected to be used as a packaging material.

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) decreases significantly.

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

Therefore, in order to improve the gas barrier properties of polyolefin films, studies are underway to laminate liquid crystal polymer films to form a composite film. However, liquid crystal polymers have insufficient adhesion with other resins, especially polyolefins, and special treatments have been required to form composite films.

For example, a composite film has been proposed in which a thermoplastic resin layer is laminated on one side of a liquid crystal polymer layer without an adhesive layer (adhesive) by subjecting the liquid crystal polymer layer to a surface treatment such as corona discharge (Patent Document 1).

Japanese Unexamined Patent Publication No. 4-135750

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, it has been desired to develop a liquid crystal polymer with improved adhesion to other resins.

An object of the present invention is to provide a liquid crystal polymer composition with improved adhesive properties. 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 the liquid crystal polymer and the polyolefin.

In view of the above-mentioned problems, the present inventors have made extensive studies and found that by blending a maleic acid-modified polyolefin with a liquid crystal polymer, a liquid crystal polymer composition with significantly improved adhesiveness can be obtained, and the present invention has been developed. It has been completed.

［式中、ｐ、ｑ、ｒ、ｓ、ｔおよびｕは、それぞれ各繰返し単位の液晶ポリマー中での組成比（モル％）を示し、以下の式を満たす：
３５≦ｐ≦５５、
２５≦ｑ≦４５、
２≦ｒ≦１５、
０≦ｓ≦５、
２≦ｔ≦１５、
０≦ｕ≦５、
ｒ≧ｓ、
ｐ＋ｑ＋ｒ＋ｓ＋ｔ＋ｕ＝１００］
〔３〕式［ＶＩ］で表される繰返し単位は、式［ＶＩＩ］で表される繰返し単位である、〔２〕に記載の液晶ポリマー組成物。

〔４〕さらにｐ＞ｑを満たす、〔２〕または〔３〕に記載の液晶ポリマー組成物。
〔５〕マレイン酸変性ポリオレフィンはマレイン酸変性ポリエチレンである、〔１〕～〔４〕のいずれかに記載の液晶ポリマー組成物。
〔６〕〔１〕～〔５〕のいず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。
〔７〕液晶ポリマー層（ａ）とポリオレフィン層（ｂ）が接着層（ｃ）を介して積層された構造を有する成形品であって、該接着層（ｃ）は〔１〕～〔５〕のいずれかに記載の液晶ポリマー組成物からなる、成形品。
〔８〕ポリオレフィン層（ｂ）はポリエチレン層である、〔７〕に記載の成形品。
〔９〕多層ブロー成形品である、〔７〕または〔８〕に記載の成形品。 That is, the present invention includes the following preferred embodiments.
[1] A liquid crystal polymer composition containing 100 parts by mass of a liquid crystal polymer having a crystal melting temperature of less than 210°C and 1 to 100 parts by mass of a maleic acid-modified polyolefin.
[2] The liquid crystal polymer composition according to [1], wherein the liquid crystal polymer is a wholly aromatic liquid crystal polyester comprising repeating units represented by formulas [I] to [VI].

[In the formula, p, q, r, s, t, and u each indicate the composition ratio (mol%) of each repeating unit in the liquid crystal polymer, and satisfy the following formula:
35≦p≦55,
25≦q≦45,
2≦r≦15,
0≦s≦5,
2≦t≦15,
0≦u≦5,
r≧s,
p+q+r+s+t+u=100]
[3] The liquid crystal polymer composition according to [2], wherein the repeating unit represented by formula [VI] is a repeating unit represented by formula [VII].

[4] The liquid crystal polymer composition according to [2] or [3], further satisfying p>q.
[5] The liquid crystal polymer composition according to any one of [1] to [4], wherein the maleic acid-modified polyolefin is maleic acid-modified polyethylene.
[6] A molded article comprising the liquid crystal polymer composition according to any one of [1] to [5].
[7] A molded product having a structure in which a liquid crystal polymer layer (a) and a polyolefin layer (b) are laminated with an adhesive layer (c) interposed therebetween, the adhesive layer (c) being one of [1] to [5] A molded article comprising the liquid crystal polymer composition according to any one of the above.
[8] The molded article according to [7], wherein the polyolefin layer (b) is a polyethylene layer.
[9] The molded product according to [7] or [8], which is a multilayer blow molded product.

The liquid crystal polymer composition of the present invention is used not only as a general molding material but also as an adhesive layer for blow-molded products and laminated films because of its excellent adhesive properties. Further, the liquid crystal polymer composition of the present invention is particularly suitably used as an adhesive material between a liquid crystal polymer and a polyolefin.

The liquid crystal polymers used in the liquid crystal polymer compositions of the present invention are liquid crystal polyesters or liquid crystal polyester amides that form an anisotropic melt phase, referred to by those skilled in the art as thermotropic liquid crystal polymers.

The nature of the anisotropic molten phase can be confirmed by the usual polarization inspection method using orthogonal polarizers, that is, by observing a sample placed on a hot stage under a nitrogen atmosphere.

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, and aromatic diamino repeating units. and aminocarbonyl repeat units and combinations thereof.

Specific examples of monomers providing aromatic oxycarbonyl repeating units include aromatic hydroxycarboxylic acids such as 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 2-hydroxybenzoic acid, and 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- Examples include 3-benzoic acid and the like, alkyl, alkoxy or halogen-substituted products thereof, and ester-forming derivatives thereof such as acylated products, ester derivatives, and acid halides. Among these, 4-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid are preferred because the mechanical properties, heat resistance, crystal melting temperature, and moldability of the resulting liquid crystal polymer can be easily adjusted to appropriate levels.

Specific examples of monomers providing aromatic dicarbonyl repeating units include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 1,6-naphthalene dicarboxylic acid, and 2,7 - Naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 4,4'-dicarboxybiphenyl, etc., their alkyl, alkoxy or halogen substituted products, and ester-forming derivatives thereof such as their ester derivatives and acid halides. Can be mentioned. Among these, terephthalic acid and 2,6-naphthalene dicarboxylic acid are preferred because the mechanical properties, heat resistance, crystal melting temperature, and moldability of the resulting liquid crystal polymer can be easily adjusted to appropriate levels.

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

Monomers that give aromatic aminooxy repeating units, aromatic diamino repeating units, and aromatic aminocarbonyl repeating units include aromatic hydroxyamines, aromatic diamines, and aromatic aminocarboxylic acids.

The liquid crystal polymer used in the present invention may contain aromatic oxydicarbonyl repeating units, fatty acid dihydroxy repeating units, fatty acid dicarbonyl repeating units, and thioester bonds, as long as the object of the present invention is not impaired. Examples of monomers that give thioester bonds include mercaptoaromatic carboxylic acids, aromatic dithiols, and hydroxyaromatic thiols. The amount of these monomers used is preferably 10 mol% or less based on the total amount of 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.

Copolymers that combine these repeating units may or may not form an anisotropic molten phase, depending on the monomer composition and composition ratio, and the sequence distribution of each repeating unit in the copolymer. However, the liquid crystal polymers used in the present invention are limited to copolymers that form an anisotropic molten phase.

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

The liquid crystal polymer used in the present invention has a crystalline melting temperature measured by a differential scanning calorimeter of less than 210°C, preferably 205°C or less, more preferably 200°C or less, and even more preferably 195°C or less. The liquid crystal polymer in the present invention has a crystalline melting temperature measured by a differential scanning calorimeter of preferably 150°C or more, more preferably 155°C or more, and even more preferably 160°C or more.

By having the crystalline melting temperature of the liquid crystal polymer be less than 210°C, the maleic acid 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.

In this 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 heating conditions 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 heating conditions of 20°C/min. After that, the endothermic peak is observed when measured again under heating conditions of 20°C/min, and the temperature showing the peak top is taken as the crystalline melting temperature of the liquid crystal polymer. For example, an Exstar 6000 manufactured by Seiko Instruments Inc. can be used as a measuring device.

As the liquid crystal polymer having a crystalline melting temperature of less than 210° C. to be used in the present invention, a wholly aromatic liquid crystal polyester comprising repeating units represented by formulae [I] to [VI] is suitable.

[In the formula, p, q, r, s, t, and u each indicate the composition ratio (mol%) of each repeating unit in the liquid crystal polymer, and satisfy the following formula:
35≦p≦55,
25≦q≦45,
2≦r≦15,
0≦s≦5,
2≦t≦15,
0≦u≦5,
r≧s,
p+q+r+s+t+u=100. ]

In the wholly aromatic liquid crystal polyester preferably used in the present invention, the composition ratio p of the repeating unit represented by formula [I] to the wholly aromatic liquid crystal polyester is preferably 35 to 55 mol%, more preferably 38 to 53 mol%. Also, the composition ratio q of the repeating unit represented by formula [II] to the wholly aromatic liquid crystal polyester is preferably 25 to 45 mol%, more preferably 28 to 43 mol%.

In the fully aromatic liquid crystal polyester preferably used in the present invention, the repeating units represented by formula [I] and formula [II] preferably satisfy the relationship p>q, and p/q is more preferably 1.01 to 2.0, even more preferably 1.03 to 1.9, and particularly preferably 1.08 to 1.8.

Examples of the monomer providing the repeating unit represented by formula [I] include 4-hydroxybenzoic acid and ester-forming derivatives thereof such as acylated products, ester derivatives, and acid halides.

Examples of monomers that give the repeating unit represented by formula [II] include 6-hydroxy-2-naphthoic acid and its ester-forming derivatives such as its acylation products, ester derivatives, and acid halides.

The fully aromatic liquid crystal polyester preferably used in the present invention contains an aromatic dioxy repeating unit represented by formula [III]. The composition ratio r of the repeating unit represented by formula [III] to the fully aromatic liquid crystal polyester is preferably 2 to 15 mol %, more preferably 4 to 14 mol %.

Examples of the monomer providing the repeating unit represented by formula [III] include 4,4'-dihydroxybiphenyl and ester-forming derivatives thereof such as acylated products thereof.

The above-mentioned wholly aromatic liquid crystal polyester suitably used in the present invention may further contain a repeating unit represented by formula [IV] as an aromatic dioxy repeating unit. The composition ratio s of the repeating unit represented by formula [IV] to the wholly aromatic liquid crystal polyester is 0 to 5 mol% in some cases, and 1 to 4 mol% in other cases.

When a repeating unit represented by formula [IV] is included as an aromatic dioxy repeating unit, the relationship r≧s is satisfied.

Examples of the monomer providing the repeating unit represented by formula [IV] include hydroquinone and ester-forming derivatives thereof such as acylated products.

The wholly aromatic liquid crystal polyester preferably used in the present invention contains an aromatic dicarbonyl repeating unit represented by formula [V]. The composition ratio t of the repeating unit represented by formula [V] to the wholly aromatic liquid crystal polyester is preferably 2 to 15 mol %, more preferably 4 to 14 mol %.

Examples of the monomer providing the repeating unit represented by formula [V] include 2,6-naphthalene dicarboxylic acid and ester-forming derivatives thereof such as ester derivatives and acid halides.

The above-mentioned wholly aromatic liquid crystalline polyester suitably used in the present invention may further contain a repeating unit represented by formula [VI] as an aromatic dicarbonyl repeating unit. The composition ratio u of the repeating unit represented by formula [VI] to the wholly aromatic liquid crystal polyester is preferably 0 to 5 mol%, more preferably 1 to 4 mol%.

When the repeating unit represented by formula [VI] is included as the aromatic dicarbonyl repeating unit, it is preferable that the relationship t ≧ u is satisfied.

Examples of the monomer providing the repeating unit represented by formula [VI] include terephthalic acid, isophthalic acid, and ester-forming derivatives thereof such as ester derivatives and acid halides. Among these, isophthalic acid is preferred because the crystal melting temperature can be adjusted lower.

That is, it is preferable that the repeating unit represented by the formula [VI] is a repeating unit represented by the following formula [VII].

In formulas [I] to [VI], p+q+r+s+t+u=100.

It is also preferable that r+s=t+u.

Two or more types of monomers may be used for each of the above monomers that give the repeating units represented by formulas [I] to [VI].

The fully aromatic liquid crystal polyester preferably used in the present invention is composed of repeating units represented by formulas [I] to [VI] as described above, but in addition to the main monomer that gives the repeating units represented by general formulas [I] to [VI], other repeating units, i.e., monomers that give repeating units other than the repeating units represented by general formulas [I] to [VI] may be copolymerized within a range that does not impair the object of the present invention. Examples of monomers that give other repeating units include aromatic hydroxycarboxylic acids, aromatic diols, aromatic dicarboxylic acids, aromatic hydroxydicarboxylic acids, aromatic hydroxyamines, aromatic diamines, aromatic aminocarboxylic acids, alicyclic dicarboxylic acids, aliphatic diols, alicyclic diols, aromatic mercaptocarboxylic acids, aromatic dithiols, and aromatic mercaptophenols. The amount of monomers that give these other repeating units is preferably 10 mol % or less of the total amount of monomers that give the repeating units represented by formulas [I] to [VI]. In the present invention, the liquid crystal polymer having a crystalline melting temperature of less than 210°C is particularly preferably a fully aromatic liquid crystal polyester that does not contain any repeating units other than those represented by the general formulas [I] to [VI], i.e., is composed of the repeating units represented by the formulas [I] to [VI].

The method for producing the liquid crystal polymer used in the present invention will be explained below.

There are no particular limitations on the method for producing the liquid crystal polymer used in the present invention, and known polycondensation methods for forming ester bonds, amide bonds, etc. made of the above-mentioned monomer combinations, such as melt acidolysis and slurry polymerization, may be used. can be used.

Melt acidolysis is the preferred method for producing the liquid crystalline polymers used in the present invention, in which the monomers are first heated to form a melt of the reactants, followed by The reaction is continued to obtain a molten polymer. Note that a vacuum may be applied to facilitate the removal of volatile by-products (eg, acetic acid, water, etc.) in the final stage of condensation.

Slurry polymerization is a method in which the reaction is carried out in the presence of a heat exchange fluid, and the solid product is obtained in suspension in the heat exchange medium.

In both the melt acidolysis method and the slurry polymerization method, the polymerizable monomer component used to produce the liquid crystal polymer is a modified form in which hydroxyl groups and/or amino groups are acylated, that is, lower It can also be used in 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 in which an acetylated product of the above monomer is used in the reaction.

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

In either the melt acidolysis method or the slurry polymerization method, a catalyst may be used as necessary during the reaction.

Specific examples of catalysts include organic tin compounds (dialkyltin oxides such as dibutyltin oxide, diaryltin oxides, etc.), titanium dioxide, antimony trioxide, organic titanium compounds (alkoxytitanium silicates, titanium alkoxides, etc.), carboxylic acid Examples include alkali and alkaline earth metal salts (potassium acetate, sodium acetate, etc.), Lewis acids ( _BF3 , etc.), gaseous acid catalysts such as hydrogen halides (HCl, etc.), and the like.

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

The liquid crystal polymer obtained by this polycondensation reaction is withdrawn from the polymerization reaction tank in a molten state and then processed into pellets, flakes, or powder.

The maleic acid modified polyolefin used in the present invention is a polyolefin in which maleic acid, maleic anhydride, or a derivative thereof has been introduced by a grafting reaction or the like, and a commercially available product may be used. Examples of commercially available products include Modic (registered trademark) M114, Modic (registered trademark) M512, and Modic (registered trademark) L502 manufactured by Mitsubishi Chemical Corporation, and UMEX (registered trademark) 2000 manufactured by Sanyo Chemical Industries, Ltd. Two or more types of maleic acid modified polyolefins may be used in combination.

In the maleic acid-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 is preferred.

In the present invention, when using maleic acid-modified polyethylene as the maleic acid-modified polyolefin, the raw material polyethylene is not particularly limited, and examples include low-density polyethylene, linear low-density polyethylene, and high-density polyethylene. These may be used alone or in combination of two or more.

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

In the liquid crystal polymer composition of the present invention, the proportion of the maleic acid-modified polyolefin is 1 to 100 parts by mass, and preferably 5 to 90 parts by mass from the viewpoint of easily exhibiting adhesive properties, with respect to 100 parts by mass of the liquid crystal polymer. It is more preferably 10 to 85 parts by weight, even more preferably 20 to 80 parts by weight, and particularly preferably 40 to 70 parts by weight.

The liquid crystal polymer composition of the present invention may contain inorganic and/or organic fillers as optional components.

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, and aluminum borate. Examples include fibers, aramid fibers, polyarylate fibers, polybenzimidazole fibers, talc, mica, graphite, wollastonite, dolomite, clay, glass flakes, glass beads, glass balloons, calcium carbonate, barium sulfate, and titanium oxide. These may be used alone or in combination of two or more.

Among these, talc is preferred because it offers an excellent balance between physical properties and cost.

Furthermore, 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 onto the surface of the filler, a method in which a surface treatment agent is added during kneading, and the like.

Surface treatment agents 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.

When blending an inorganic and/or organic filler, the content thereof is preferably 1 to 150 parts by mass, and 10 to 100 parts by mass, based on 100 parts by mass of the total amount of the liquid crystal polymer and maleic acid-modified polyolefin. It is more preferable that

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 mechanical strength and heat resistance by the inorganic and/or organic filler in the liquid crystal polymer composition, and if the content exceeds 150 parts by mass. and liquidity tends to decline. In the present invention, the liquid crystal polymer composition preferably does not contain inorganic and/or organic fillers.

In addition to the liquid crystal polymer and the maleic acid-modified polyolefin, other additives and resin components may be added to the liquid crystal polymer composition of the present invention as long as the object of the present invention is not impaired.

Specific examples of other additives include higher fatty acids as lubricants, higher fatty acid esters, higher fatty acid amides, higher fatty acid metal salts (herein, higher fatty acids refer to those having 10 to 25 carbon atoms), etc. , mold release agents such as polysiloxane and fluororesin, coloring agents such as dyes, pigments, and carbon black, flame retardants, antistatic agents, surfactants, and nucleating agents such as talc, organic phosphates, and sorbitol. Examples include anti-blocking agents, antioxidants such as phosphorus antioxidants, phenolic antioxidants, sulfur-based antioxidants, weathering agents, heat stabilizers, and neutralizing agents. These additives can be used alone or in combination of two or more.

The total amount of other additives in the liquid crystal polymer composition is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the total amount of the liquid crystal polymer and the maleic acid modified polyolefin.

If the total amount of other additives is less than 0.01 parts by mass, it is difficult for the additives to function, and if it exceeds 5 parts by mass, the thermal stability of the liquid crystal polymer composition during molding tends to deteriorate.

In addition, among the other additives mentioned above, when using additives such as lubricants, mold release agents, and anti-blocking agents, they may be added when producing the liquid crystal polymer composition, or when molding the liquid crystal polymer composition. It may also be attached to the surface of pellets of the polymer composition.

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.

When other resin components are contained, the content is preferably 100 parts by mass or less, and more preferably 80 parts by mass or less, per 100 parts by mass of the total amount of the liquid crystal polymer and the maleic acid modified polyolefin. In the present invention, it is preferable that the liquid crystal polymer composition does not contain other additives and other resin components.

The liquid crystal polymer composition of the present invention can be obtained by blending the above liquid crystal polymer, maleic acid 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 the mixture using a Banbury mixer, kneader, 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 maleic acid modified polyolefin, and melt-kneading the mixture in a molding machine.

The liquid crystal polymer composition of the present invention is processed into films, sheets, bottles, containers, packaging materials, etc. by known molding methods such as injection molding, extrusion molding, and blow molding.

Among these, injection molding, extrusion molding, and blow molding are preferred from the standpoint of ease of molding, mass productivity, cost, etc.

When injection molding is adopted, the injection molding machine used for injection molding is not particularly limited, but may be of any mold clamping mechanism type, such as a direct pressure type (hydraulic type) or a toggle type, or a screw type ( The injection method may be any injection method such as a screw pre-plastic type, in-line screw type, etc.) or a plunger method (single plunger type, plunger pre-plastic type, etc.).

The direction of the cylinder can be either horizontal or vertical, and the drive mechanism can be hydraulic, electric, or a combination of both.

The optimum injection conditions can be selected according to the size of the injection molding machine, the shape of the mold, and the number of pieces. The gate position and number of gates can be selected according to the type of injection molded product.

In addition to the above-mentioned normal injection molding methods, injection molding methods also include injection molding methods that apply insert molding, injection compression molding, two-color molding, sandwich molding, gas-assisted molding, etc.

When extrusion molding or blow molding is used, it can be processed into films, sheets, containers, pipes, fibers, etc., and can be made into single or single-layer molded products, and other resin compositions can be used to improve functionality and reduce costs. It may also be a composite or multilayer molded body having parts or layers made of a material. It is also possible to uniaxially or biaxially stretch films, sheets, fibers, etc. Further, the obtained molded product may be subjected to secondary processing such as bending, vacuum forming, blow molding, press molding, etc. to obtain the desired molded product, if necessary.

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 in 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. Such molded products can be obtained by the above molding method, but it is preferable that the molded product is a multilayer blow molded product obtained by blow molding.

Furthermore, molded articles made from the liquid crystal polymer composition of the present invention can be processed into desired molded articles by blow molding, which is suitable for molding hollow products such as bottles. Specific blow molding methods include direct blow molding, injection blow molding, and free blow molding. In particular, since the adhesion between the liquid crystal polymer layer and the polyolefin layer is improved, it is suitable for multilayer blow molding by direct blow molding or injection blow molding.

Moreover, the temperature conditions when molding using the liquid crystal polymer composition of the present invention are preferably within the range of the crystal melting temperature (less than 210°C) of the liquid crystal polymer used to 300°C.

Molded products made from the resin composition of the present invention include, but are not particularly limited to, mechanical parts, electrical/electronic parts, architectural/civil engineering parts, household/office supplies, furniture parts, and daily necessities. Molded articles are particularly useful as containers.

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, housings for ICs and LEDs, sockets, relays, resistors, condensers, coil bobbins, etc.).

Furthermore, since the liquid crystal polymer composition of the present invention has excellent adhesive properties to both liquid crystal polymers and resins such as polyolefins, it is useful as an adhesive material, for example, as an adhesive layer in a laminated film. Available.

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 which polyolefins are preferred and polyethylene is more preferred.

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 in which the adhesive strength of the liquid crystal polymer composition of the present invention to the liquid crystal polymer is usually 220 N or more, preferably 250 to 500 N, and more preferably 280 to 480 N is suitable.

When the polyolefin is polyethylene, the adhesion of the liquid crystal polymer composition of the present invention to a polyolefin can be evaluated by the adhesive strength (90-degree peel strength) according to JIS-C-6471. A composite in which the adhesive strength of the liquid crystal polymer composition of the present invention to a polyolefin (e.g., LLDPE) is usually 5 N or more, preferably 8 to 50 N, and more preferably 10 to 30 N, is suitable.

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples, but the present invention is not limited thereto.

The crystal melting temperature and adhesion properties in the Examples were measured by the methods described below.

<Measurement of crystal melting temperature>
The measurement was performed using a differential scanning calorimeter (DSC) Exstar 6000 manufactured by Seiko Instruments. A liquid crystal polymer sample is measured under the condition of increasing the temperature from room temperature to 20° C./min, and after observing the endothermic peak temperature (Tm1), it is held at a temperature 20 to 50° C. higher than Tm1 for 10 minutes. Next, after cooling the sample to room temperature under a temperature decreasing condition of 20°C/min, the endothermic peak was observed when measuring again under a temperature increasing condition of 20°C/min, and the temperature showing the top of the peak was determined as the crystal melting temperature of the liquid crystal polymer. shall be.

<Adhesion test with liquid crystal polymer>
Using an injection molding machine (UH1000-110 manufactured by Nissei Plastics Co., Ltd.), a molding temperature of 250°C and a mold temperature of 40°C were used to mold barflow test pieces (length 150 mm x width 13 mm x thickness 0.8 mm) of the liquid crystal polymer (LCP of Synthesis Example 1) and the adhesive layer (liquid crystal polymer composition obtained in the Examples and Comparative Examples). The obtained barflow test pieces were overlapped 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 in accordance with JIS-K-7162 using an INSTRON5567 (a universal testing machine manufactured by Instron Japan Co., Ltd.).

<Adhesion test with linear low density polyethylene>
Using an injection molding machine (UH1000-110 manufactured by Nissei Plastic Industrial 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 be bonded. The adhesive strength (90 degree peel strength) was measured in accordance with JIS-C-6471 using an INSTRON5567 (a universal testing machine manufactured by Instron Japan Co., Ltd.).

In 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 BP: 4,4'-dihydroxybiphenyl NDA: 2,6-naphthalene dicarboxylic acid IPA: Isophthalic acid acid

[Synthesis example 1 (LCP synthesis)]
POB, BON6, BP, NDA, and IPA were charged in the composition ratio shown in Table 1 to a reaction vessel equipped with a stirring device equipped with a torque meter and a distillation tube, and the total amount was 6.5 mol. Acetic anhydride was charged in an amount of 1.03 times the mole of hydroxyl groups, and acetic acid removal polymerization was carried out under the following conditions.

Under a nitrogen gas atmosphere, the temperature was raised from room temperature to 150°C over 1 hour and maintained at that temperature for 30 minutes. Next, the temperature was quickly raised to 210°C while distilling off the by-product acetic acid, and maintained at that temperature for 30 minutes. The temperature was then raised to 340°C over 4 hours, and the pressure was then reduced to 10 mmHg over 80 minutes. The polymerization reaction was terminated when a predetermined torque was reached, the contents of the reaction vessel were removed, and LCP pellets were obtained using a grinder. The amount of acetic acid distilled during polymerization was almost the theoretical value.

The crystalline melting temperature of the obtained LCP measured by DSC was 183°C.

In addition to the LCP synthesized in the above Synthesis Example, materials used in the Examples and Comparative Examples are shown below.
LLDPE: "Ultsex (registered trademark) 4570" manufactured by Prime Polymer Co., Ltd.
Maleic acid modified polyethylene 1: "Modic (registered trademark) M114" manufactured by Mitsubishi Chemical Corporation
Maleic acid modified polyethylene 2: "Modic (registered trademark) M512" manufactured by Mitsubishi Chemical Corporation
Ethylene-glycidyl methacrylate copolymer: "Bondfast (registered trademark) E" manufactured by Sumitomo Chemical Co., Ltd.

Examples 1 to 3 and Comparative Examples 1 to 2
The LCP synthesized in the synthesis example and the above materials were mixed in the amounts 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.

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

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

Claims (8)

Containing 100 parts by mass of a liquid crystal polymer having a crystal melting temperature of less than 210 ° C. and 1 to 100 parts by mass of maleic acid-modified polyolefin ,
The liquid crystal polymer has formulas [I] to [VI]

[In the formula, p, q, r, s, t, and u each indicate the composition ratio (mol%) of each repeating unit in the liquid crystal polymer, and satisfy the following formula:
35≦p≦55,
25≦q≦45,
2≦r≦15,
0≦s≦5,
2≦t≦15,
0≦u≦5,
r≧s,
p+q+r+s+t+u=100]
A wholly aromatic liquid crystalline polyester comprising a repeating unit represented by
A liquid crystal polymer composition that does not contain other resin components, or when it contains other resin components, the content is 100 parts by mass or less based on 100 parts by mass of the total amount of the liquid crystal polymer and maleic acid-modified polyolefin. thing. 2. The liquid crystal polymer composition according to claim 1 , wherein the repeating unit represented by formula [VI] is a repeating unit represented by formula [VII].

The liquid crystal polymer composition according to claim 1 or 2 , further satisfying p>q. 4. The liquid crystal polymer composition according to claim 1 , wherein the maleic acid-modified polyolefin is maleic acid-modified polyethylene. A molded article comprising the liquid crystal polymer composition according to any one of claims 1 to 4 . 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 4 . 7. The molded article according to claim 6 , wherein the polyolefin layer (b) is a polyethylene layer. The molded article according to claim 6 or 7 , which is a multi-layer blow molded article.