JPH08300523A - Multi-layer tubular molding - Google Patents

Abstract

PURPOSE: To obtain a tubular molding suitable for engineering use with good toughness and heat resistance and having a low coefficient of linear expansion by at least containing a layer consisting of a resin composition with liquid crystal polyester resin forming an anisotropic melting phase and thermoplastic resin not forming an anisotropic melting phase contained therein, and a thermoplastic resin layer forming an anisotropic melting phase. CONSTITUTION: Various methods are applicable for each method of blending liquid crystal polyester resin (a) of an A layer and thermoplastic resin (b), and blending thermoplastic resin C of a B layer and additives. For an apparatus to carry out melt-mixing, there is given a blending roller, a Banbury mixer, a kneader, an extruder and so forth, among these, however, an extruder is used preferably. Although the ratio between each thickness of A layer made up of the liquid crystal polyester resin (a) and thermoplastic resin (b) and the B layer made up of the thermoplastic resin (C) is not limited in particular, A-layer/B-layer is set to be 0.2-5 preferably in view of a moldability, and particularly to be 0.4-3 preferably.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is usefully used as electric / electronic equipment parts, automobile parts, machine parts, etc., and has excellent mechanical properties and toughness, such as tubes, hoses, pipes, etc.
That is, the present invention relates to a tubular molding for engineering.

[0002]

2. Description of the Related Art In recent years, demands for higher performance of plastics have been increasing, and many polymers having various new properties have been developed and put on the market. Among them, optics characterized by parallel arrangement of molecular chains Attention is paid to the fact that anisotropic liquid crystalline resins have excellent fluidity and mechanical properties (JP-A-51-8395 and JP-A-49-7239).
3 gazette). However, at present, the applications are limited because the molding shrinkage and mechanical properties are different in the direction perpendicular to the molecular chain orientation and the cost is high. on the other hand,
It is known that many thermoplastic resins do not necessarily have sufficient mechanical properties and heat resistance as compared with liquid crystalline resins.

In order to solve the drawbacks of both, a blend of a liquid crystalline resin and a thermoplastic resin has been attracting attention (Japanese Patent Application Laid-Open No. 57-25254). It is known that a tubular molded product obtained from the blend of the liquid crystalline resin and the thermoplastic resin has excellent mechanical properties, heat resistance and a low linear expansion coefficient (Japanese Patent Laid-Open No. 63-241068, Japanese Laid-Open Patent Publication No. 5
-4292, JP-A-5-186668),
A wide range of applications such as electric / electronic device parts, automobile parts, and machine parts are expected.

[0004]

However, a tubular molded article obtained from a blend of a liquid crystalline resin and a thermoplastic resin is more likely to fibrillate than one made of a thermoplastic resin, so that the surface appearance is inferior and the toughness is not always sufficient. Had the problem.

Therefore, the present invention solves the above-mentioned problems and is excellent in toughness, surface appearance, mechanical properties, and heat resistance, and particularly has a low linear expansion coefficient, particularly electric / electronic equipment parts, automobile parts, mechanical parts, etc. An object is to obtain a tubular molded body suitable for engineering applications.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that at least a layer made of (A) a liquid crystalline resin and a thermoplastic resin and (B) a layer made of a thermoplastic resin. It has been found that a tubular molded body having excellent surface appearance and toughness and having a low linear expansion coefficient can be obtained by using a multilayer structure composed of two kinds of layers, and thus the present invention has been accomplished.

That is, the present invention comprises (1) two or more layers including at least a layer (A) and a layer (B),
The layer (A) is made of a resin composition containing a liquid crystal polyester resin (a) that forms an anisotropic molten phase and a thermoplastic resin (b) that does not form an anisotropic molten phase, and the layer (B) is A multilayer tubular molded article, characterized by comprising a thermoplastic resin (c) which does not form an anisotropic molten phase, (2) the multilayer tubular article is a two-layer tubular article, and the (A) layer is an outer layer (B) layer (3) A liquid crystal polyester resin (a) in which the layer (A) forms an anisotropic molten phase and 1 to 50% by weight of a thermoplastic resin which does not form an anisotropic molten phase. Resin (b) 99-
1 to 50% by weight of a liquid crystal polyester resin (a) in which the layer (A) forms an anisotropic melt phase, wherein the multilayer tubular molded article is composed of a resin composition comprising 50% by weight.
And thermoplastic resin (b) 99-5 that does not form an anisotropic molten phase
The multilayer tubular molded product according to claim 1, which is composed of a resin composition in which 0.01 to 20 parts by weight of the epoxy compound (d) is further added to 100 parts by weight of the compounded product of 0% by weight, (5). Liquid crystal polyester forming an anisotropic molten phase resin (a) is a liquid crystal polyester resin consisting of the following structural units (I) ~ (IV) multilayer tubular molded article described above,

[Chemical 4] (However, R1 in the formula is

Embedded image R1 represents one or more groups selected from

[Chemical 6] Represents one or more groups selected from In the formula, X represents a hydrogen atom or a chlorine atom, and the structural unit [(II) + (III)]
And the structural units (IV) are substantially equimolar. (6) The above-mentioned multilayer tubular molded article in which the thermoplastic resin (b) which does not form an anisotropic molten phase is polybutylene terephthalate and (7) the thermoplastic resin (c) which does not form an anisotropic molten phase It is the above-mentioned multilayer tubular molded article which is polybutylene terephthalate.

The multilayer tubular molded article of the present invention comprises a resin composition containing a liquid crystal polyester resin (a) forming an anisotropic molten layer and a thermoplastic resin (b) not forming an anisotropic molten layer. (A) layer and a (B) layer composed of a thermoplastic resin (c) which does not form an anisotropic molten layer, and a multilayer tubular molded article comprising at least two layers. This multilayer tubular molded body may have a layer of the third component other than the (A) layer and the (B) layer, and may have a plurality of either or both of the (A) layer and the (B) layer. . From the viewpoints of formability, toughness, and coefficient of linear expansion, the (A) layer may be an inner layer or an outer layer having a two-layer structure, but it is particularly preferable that the (A) layer is an outer layer and the (B) layer is an inner layer. .

Liquid crystal polyester resin (a) used in the present invention
Is a polyester that forms an anisotropic melt phase, p
-Hydroxybenzoic acid / polyethylene terephthalate type liquid crystal polyester, p-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid type liquid crystal polyester, p-hydroxybenzoic acid / 4,4'-dihydroxybiphenyl /
Examples thereof include terephthalic acid / isophthalic acid type polyesters, and among them, liquid crystal polyesters having the structural units (I) to (IV) are preferable.

The above structural unit (I) is a structural unit of polyester produced from p-hydroxybenzoic acid, and the structural unit (II) is 4,4'-dihydroxybiphenyl, 3,
3 ', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl, hydroquinone, t-butylhydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,2-bis (4-hydroxyphenyl) ) A structural unit produced from an aromatic dihydroxy compound selected from propane and 4,4'-dihydroxydiphenyl ether, a structural unit (III) is a structural unit produced from ethylene glycol, and a structural unit (IV) is terephthalic acid or isophthalic acid. Acid, 4,4'-diphenylcarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid, 1,
2-bis (2-chlorophenoxy) ethane-4,4'-
Structural units formed from an aromatic dicarboxylic acid selected from dicarboxylic acid and diphenyl ether dicarboxylic acid are shown below. Of these, R1

[Chemical 7] Is 70 mol% or more of the structural unit (II), and R2 is

Embedded image Particularly preferably those having 70 mol% or more of the structural unit (IV).

The above structural units (I), (II), (III) and (I
The copolymerization amount of V) is arbitrary. However, from the viewpoint of fluidity, the following copolymerization amount is preferable. That is, from the viewpoint of heat resistance and mechanical properties, the structural unit [(I) + (II)] is preferably 60 to 95 mol% of [(I) + (II) + (III)], and 70 to 92 mol% % Is more preferable. Also, the structural unit
(III) is preferably 40 to 5 mol% of [(I) + (II) + (III)], and more preferably 25 to 15 mol%. The molar ratio of structural unit (I) / (II) is preferably 75/25 to 95/5, more preferably 78/22 to 93/7 from the viewpoint of the balance between heat resistance and fluidity. Also, the structural unit
(IV) is substantially equimolar to the structural unit [(II) + (III)].

In the polycondensation of the preferred liquid crystal polyester, 3,3'-diphenyldicarboxylic acid and 2,2'-, in addition to the components constituting the structural units (I) to (IV), are used.
Aromatic dicarboxylic acids such as diphenyldicarboxylic acid, adipic acid, azelaic acid, sebacic acid, aliphatic dicarboxylic acids such as dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone,
Methyl hydroquinone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxybenzophenone, 3,
Aromatic diol such as 4'-dihydroxybiphenyl,
1,4-butanediol, 1,6-hexanediol,
Aliphatic and alicyclic diols such as neopentyl glycol, 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, and m-hydroxybenzoic acid,
Aromatic hydroxycarboxylic acids such as 2,6-hydroxynaphthoic acid and p-aminophenol, p-aminobenzoic acid and the like may be copolymerized in amounts that do not impair the object of the present invention.

Liquid crystal polyester resin (a) in the present invention
The method for producing is not particularly limited, and it can be produced according to a known polyester polycondensation method.

For example, in the production of the above preferably used liquid crystal polyester resin, the following production method is preferably exemplified.

(1) p-acetoxybenzoic acid, 4,4 '
-Diacylated aromatic dihydroxy compounds such as diacetoxybiphenyl and diacetoxybenzene, aromatic dicarboxylic acids such as terephthalic acid, and polyester polymers such as polyethylene terephthalate, oligomers, and aromatics such as bis (β-hydroxyethyl) terephthalate A method for producing a bis (β-hydroxyethyl) ester of a dicarboxylic acid group by a deacetic acid polycondensation reaction.

(2) p-hydroxybenzoic acid, 4,4 '
-Aromatic dihydroxy compounds such as dihydroxybiphenyl and hydroquinone, aromatic dicarboxylic acids such as acetic anhydride and terephthalic acid, polyester polymers such as polyethylene terephthalate, oligomers or aromatic dicarboxylic acids such as bis (β-hydroxyethyl) terephthalate And a bis (β-hydroxyethyl) ester of the above are produced by deacetic acid polycondensation reaction.

(3) In the production method of (1) or (2), 1,2-bis (4-hydroxybenzoyl) ethane is used as a part of the starting material as described in JP-A-3-59024. Method.

Although these polycondensation reactions proceed without a catalyst, stannous acetate, tetrabutyl titanate, potassium acetate and sodium acetate, antimony trioxide, metal compounds such as magnesium metal can be used.

The above-mentioned preferred liquid crystal polyester resin used in the present invention is one capable of measuring the logarithmic viscosity in pentafluorophenol, in which case it is 0.1.
The value measured at 60 ° C. at a concentration of g / dl is preferably 0.5 or more, and particularly preferably 1.0 to 3.0 dl / g.

The melt viscosity of the liquid crystal polyester resin (a) in the present invention is preferably 10 to 20,000 poise, and more preferably 20 to 10,000 poise.

The melt viscosity is the melting point (Tm) +10.
It is a value measured by a Koka type flow tester under conditions of a shear rate of 1,000 (1 / sec) under conditions of ° C.

Here, the melting point (Tm) is the endothermic peak temperature (T) observed in the differential calorimetric measurement when the polymerized polymer is measured from room temperature at a temperature rising condition of 20 ° C./min.
After the observation of m1), the temperature was maintained at Tm1 + 20 ° C for 5 minutes, then once cooled to room temperature under the temperature lowering condition of 20 ° C / min, and then measured again under the temperature rising condition of 20 ° C / min. Refers to the endothermic peak temperature (Tm2).

The thermoplastic resin (b) used in the present invention or
As (c), a polyester that does not form an anisotropic melt phase,
Examples thereof include crystalline resins such as polyamide, polyarylene sulfide, polyoxymethylene, polyolefin-based polymers and polystyrene, and amorphous resins such as polycarbonate, polyarylate and polyarylene oxide. These may be used alone or in combination of two or more. Of these, polyester, polyarylene sulfide, polypropylene, polyethylene and polycarbonate are preferred. Among them, polyester is particularly preferable.

The thermoplastic polyester is a polyester which is thermoplastic and has an aromatic ring in the chain unit of the polymer, and is an aromatic dicarboxylic acid (or its ester-forming derivative) and a diol (or its ester-forming derivative). Is a polymer or copolymer obtained by a condensation reaction containing as a main component. Examples of the dicarboxylic acid here include terephthalic acid, isophthalic acid, phthalic acid, 2,
6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, bis (p
-Carboxyphenyl) methane, anthracene dicarboxylic acid, 4,4'-biphenylcarboxylic acid, 4,4-diphenylethercarboxylic acid, 1,2-bis (p-carboxyphenoxy) ethane, or its ester-forming derivative. . In addition, at about 30 mol% or less, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, and dimer acid, 1,4-
It may be substituted with an alicyclic carboxylic acid such as cyclohexanedicarboxylic acid or 1,3-cyclohexanedicarboxylic acid. As the diol component, an aliphatic diol having 2 to 10 carbon atoms, that is, ethylene glycol, propylene glycol, butylene glycol, 1,5-pentane glycol, decamethylene glycol, 3-methyl-
1,3-propenediol, neopentyl glycol,
Examples thereof include, but are not limited to, cyclohexanedimethanol. Specific examples of preferable polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene-1,2-bis (phenoxy) ethane-4,4'-dicarboxylate, polyethylene-2,6-naphthalate, poly-1,4-. Cyclohexanedimethylene terephthalate etc. and polyethylene terephthalate / isophthalate, polybutylene terephthalate / isophthalate, polybutylene terephthalate / sebacate, polybutylene terephthalate / decane dicarboxylate, poly-1,4-cyclohexane dimethylene terephthalate / isophthalate etc. Polymerized polyester can be used. Of these, preferred polyesters include polybutylene terephthalate, polyethylene terephthalate and poly-1,4-
Cyclohexane dimethylene terephthalate is mentioned. Furthermore, polybutylene terephthalate is more preferable. Polybutylene terephthalate has an inherent viscosity of 0.9 to
It is preferably 1.3 dl / g, and more preferably 0.92 to 1.25 dl / g. The logarithmic viscosity of polybutylene terephthalate is obtained by dividing the logarithm of the relative viscosity obtained by using a 0.5% orthochlorophenol solution at 25 ° C. by the concentration.

As the polyamide, a polyamide obtained from ω-amino acid or ω-lactam, or a dicarboxylic acid such as diamine or m-xylenediamine and adipic acid, sebacic acid, dodecanedioic acid, cyclohexanedicarboxylic acid, terephthalic acid or isophthalic acid. And a homopolymer or a copolymer obtained from the above, a mixed copolymer, and the like.
Preferred polyamides are nylon 6 and nylon 1
1, homopolyamides such as nylon 12, nylon 46, nylon 66, and adipic acid / terephthalic acid / hexamethylenediamine, adipic acid / 1,4-cyclohexanedicarboxylic acid / hexamethylenediamine, adipic acid / 1,3-cyclohexanedicarboxylic acid Examples thereof include copolyamides such as acid / hexamethylenediamine, terephthalic acid / isophthalic acid / hexamethylenediamine / paraaminocyclohexylmethane.

The polyarylene sulfide is a compound in which an aromatic ring and sulfur are bound. Examples of preferable polyarylene sulfide include polyparaphenylene sulfide and the like, which may be partially branched.

Examples of polyoxymethylene include polyoxymethylene homopolymers and copolymers whose main chain is composed mainly of oxymethylene chains.

Examples of the polyolefin-based polymer include homopolymers or copolymers containing a repeating unit formed from α-olefins such as ethylene and propylene as a main component. For example, a homopolymer of propylene, a homopolymer of ethylene, and further A block or random copolymer obtained by copolymerizing ethylene with another α-olefin (for example, propylene and butene-1), specifically, a copolymer of ethylene and an α-olefin having 3 or more carbon atoms (for example, ethylene / propylene copolymer). Polymer, ethylene / butene-1 copolymer, etc.), ethylene, α having 3 or more carbon atoms
-A copolymer composed of an olefin and a non-conjugated diene (for example, an ethylene / propylene / 1,4-hexanediene copolymer, an ethylene / propylene / dicyclopentadiene copolymer, an ethylene / propylene / ethylidene norbornene copolymer, etc.) And these are one or two.
It can be used in more than one species. Preferred polyolefin-based polymers are polypropylene homopolymer, polyethylene homopolymer, copolymers of ethylene having an ethylene content of 50 mol% or more and α-olefins having 3 or more carbon atoms (for example, ethylene / propylene copolymer, ethylene / butene-polymer). 1 copolymer), a propylene / ethylene copolymer having an ethylene content of 30 mol% or less, an elastomeric copolymer composed of 50 wt% or less of ethylene, an α-olefin having 3 or more carbon atoms and a non-conjugated diene, and polypropylene. Composition consisting of homopolymer, elastomer containing 50 wt% or less ethylene, α-olefin having 3 or more carbon atoms and non-conjugated diene, polyethylene homopolymer and propylene content 30 mol%
The following propylene / ethylene copolymers may be mentioned.

Further, it is more preferable that the above polyolefin copolymer is modified with an unsaturated carboxylic acid or a derivative thereof. Examples of the unsaturated carboxylic acid to be modified include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, 5-norbornene-2,3-dicarboxylic acid, tetrahydrophthalic acid and dimer acid. Examples of the derivative include anhydrides, esters, amides, imides and salts of the above acids.

As polystyrene, in addition to polystyrene homopolymer, HIPS (high impact polystyrene), A
S (acrylonitrile / styrene copolymer), ABS
(Acrylonitrile / butadiene / styrene copolymer), MBS (methyl methacrylate / butadiene / styrene copolymer) and the like.

Examples of the polycarbonate or polyarylate include bis (4-hydroxyphenyl), bis (3,3)
5-dialkyl-4-hydroxyphenyl) or those based on hydrocarbon derivatives having bis (3,5-dihalo-4-hydroxyphenyl) substitution are preferred,
Polycarbonates or polyarylates based on 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) are particularly preferred. Moreover, these may contain a small amount of copolymerization components.

As the polyarylene oxide, poly (2,6-dimethyl-1,4-phenylene) ether,
2,6-dimethylphenol / 2,4,6-trimethylphenol copolymer, 2,6-dimethylphenol /
2,3,6-triethylphenol copolymer and the like can be mentioned. These can be used by modifying with unsaturated carboxylic acid or its derivative by graft reaction. Examples of the unsaturated carboxylic acid to be modified include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, 5-norbornene-2,3-dicarboxylic acid, tetrahydrophthalic acid and dimer acid. The derivatives include anhydrides, esters, amides of the above acids,
Examples thereof include imide and salt. In addition, styrene resins such as polystyrene and impact polystyrene can be added to the polyarylene oxide.

Liquid crystalline polyester resin (a) forming an anisotropic melt layer and thermoplastic resin (b) not forming an anisotropic melt layer
The composition of (a) is 1 to 50% by weight, (b) is 99 to 50% by weight, and (a) is 5 to 40% by weight, and (b) is 95 to 6%.
0% by weight is preferred, (a) 5 to 35% by weight
On the other hand, (b) is most preferably 95 to 65% by weight. If the addition amount of the liquid crystal polyester resin (a) exceeds 50%, the fluidity and toughness are deteriorated, and conversely, if it is less than 1%, the effect of improving the physical properties is very small, which is not preferable.

The resin composition constituting the layer (A) may further contain an epoxy compound for improvement. The structure is not necessarily limited. The number of epoxy groups in these epoxy compounds is preferably 2 or more, and most preferably 2. Specific examples of this epoxy compound include the following compounds. Bisphenol A diglycidyl ether, orthophenylphenol glycidyl ether, glycidyl ethers synthesized from phenols and epichlorohydrin. Glycidyl ester ethers composed of epicarboxylic acid and hydroxycarboxylic acid such as p-hydroxybenzoic acid glycidyl ester ether. Diglycidyl hexahydrophthalate, diglycidyl tetrahydrophthalate, glycidyl phthalate, diglycidyl terephthalate, diglycidyl isophthalate, glycidyl methacrylate, diglycidyl dimer obtained by dimerizing dimer acid synthesized from stearic acid, 6-ethyl-1, Glycidyl esters such as 11-dodecanedicarboxylic acid diglycidyl. Epoxidized imide compounds such as N-glycidyl phthalimide. An epoxy group-containing copolymer comprising an unsaturated monomer having an epoxy group such as epoxidized polybutadiene and glycidyl methacrylate, and another unsaturated monomer such as ethylene. Epoxysilanes usually used as silane coupling agents such as γ-glycidoxypropyltrimethoxysilane. These epoxy compounds may be used alone or in combination of two or more.

Of the above epoxy compounds, glycidyl ester ethers and glycidyl esters are most preferable. Further, among these classes, epoxy compounds having no aromatic ring in the main chain are preferable. Specific examples thereof include diglycidyl dimer and diglycidyl 6-ethyl-1,11-dodecanedicarboxylate. The epoxy equivalent of the epoxy compound used is preferably 100 or more, more preferably 200 or more.

The compounding amount of the epoxy compound (d) is such that the liquid crystal polyester resin (a) which forms an anisotropic melt phase is used.
The amount is preferably 0.01 to 20 parts by weight, and particularly preferably 0 to 100 parts by weight of a blend of 1 to 50% by weight and a thermoplastic resin (b) which does not form an anisotropic molten phase in an amount of 99 to 50% by weight. 1 to 10 parts by weight.

A resin composition comprising a liquid crystal polyester resin (a) and a thermoplastic resin (b) constituting the (A) layer of the multilayer tubular molded article of the present invention or a thermoplastic resin constituting the (B) layer.
In producing (c), conventionally known polyester or polyolefin polymerization catalysts, heat-resistant agents, weather-resistant agents, antistatic agents, dyes, colorants, crystal nucleating agents, additives such as flame retardants, talc, clay, Mica, calcium metasilicate,
It is also possible to add inorganic fillers such as silica sand, glass beads, glass flakes, graphite, potassium whisker titanate, aluminum borate fibers, gypsum fibers, and reinforcing agents such as glass fibers, asbestos fibers and carbon fibers. is there.

Particularly, the flame retardant is preferably an organic polymer flame retardant. As the organic polymer flame retardant, those having a bromine atom in the molecule are preferable, and those having a bromine content of 20% by weight or more are particularly preferable. Specific examples thereof include brominated polycarbonate (for example, a polycarbonate oligomer produced using brominated bisphenol A as a raw material or a copolymer thereof with bisphenol A), a brominated epoxy compound (for example, produced by reacting brominated bisphenol A with epichlorohydrin). Diepoxy compounds or monoepoxy compounds obtained by the reaction of brominated phenols with epichlorohydrin), poly (brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, condensate of cyanuric chloride and brominated phenol, bromine Halogenated polymers and oligomers such as modified polystyrene (brominated polystyrene, polymer of brominated styrene), cross-linked brominated polystyrene, cross-linked brominated poly α-methylstyrene, etc. , Ethylene bis- (tetrabromophthalimide), brominated epoxy oligomer or polymer, brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and brominated polycarbonate are preferable, and brominated polystyrene is preferable. Particularly preferably used.

The amount of these organic polymer flame retardants added is 0,0 per 100 parts by weight of the resin composition comprising the liquid crystal polyester resin (a) and the thermoplastic resin (b) or the thermoplastic resin (c).
2 to 30 parts by weight is preferable, and 0.5 to 20 parts by weight is more preferable.

In the present invention, the method of mixing the liquid crystal polyester resin (a) and the thermoplastic resin (b) of the layer (A) or the method of mixing the thermoplastic resin (c) and the additive etc. of the layer (B). For this, various methods can be applied. As a device for melt mixing, a mixing roll, a Banbury mixer,
Examples thereof include a kneader and an extruder, and the extruder is preferable among them. As the extruder, either a single screw or a screw having two or more screws can be used, but it is particularly preferable to use a twin screw extruder.

In the present invention, the resin composition and the thermoplastic resin obtained as described above are molded into a multi-layered tubular shape. The molding method is a usual method such as injection molding, extrusion molding or blow molding. Although the method is applicable, extrusion molding is particularly preferable. In addition, “Plastic Age” No.
5 (1991) p. The shear-controlled oriented extrusion technique as disclosed in 181 can also be exemplified as a preferable method for obtaining the multilayer tubular molded product of the present invention.

As the extrusion molding, for example, a method in which two or more extruders are connected by a multi-layer pipe extrusion die, a sizing die and a cooling tank are installed in the die, and a take-up machine is used to form and cool to a predetermined cylindrical dimension. And so on. As a die for extrusion of multi-layer pipes, a two-kind two-layer pipe die for making a two-layer pipe with two extruders, a three-kind three-layer pipe die for making a three-layer pipe with three extruders, or a three-layer pipe with two extruders Examples thereof include a two-layer, three-layer pipe die, and the like, and extrusion molding can be performed using a multilayer pipe extrusion die according to the purpose. Examples of the sizing method include multi-plate sizing, slip sizing, air pressure sizing, inner surface sizing, roll sizing, driver vacuum sizing, and wet vacuum sizing.

The multilayer tubular molding of the present invention comprises a liquid crystal polyester resin (a) and a thermoplastic resin (b) (A).
The thickness ratio of the layer and the (B) layer comprising the thermoplastic resin (c) is not particularly limited, but from the viewpoint of moldability, the (A) layer / (B) layer is preferably 0.2 to 5, and 0.4 to 3 is particularly preferred.

The multilayer tubular molded product of the present invention is excellent in toughness, surface appearance, mechanical properties and heat resistance, and in particular has a low linear expansion coefficient, so that it is necessary to use these characteristics for electrical / electronic equipment parts, information. Equipment parts, precision equipment parts, automobile parts, machine parts, civil engineering / construction parts, medical equipment, safety parts, sports
Tubes used for leisure products and daily necessities,
It can be used for engineering applications such as pipes, hoses and tubular parts.

[0045]

The present invention will be described in more detail with reference to the following examples.
First, the method of measuring the coefficient of linear expansion and the method of evaluating brittleness performed in Examples and Comparative Examples will be described.

(1) Measurement of coefficient of linear expansion Using a thermomechanical analyzer (TMA100 manufactured by Seiko Denshi Kogyo Co., Ltd.), a horizontal aluminum pan was placed at the interface between the probe and the two-layer tubular molding having a length of 10 mm. Then, the temperature was raised from room temperature to 80 ° C. under the conditions of a heating rate of 5 ° C./min and a probe load of 0 mN, and after cooling, the temperature was raised again from room temperature to 80 ° C. under the same conditions. The expansion amount of the two-layer tubular molded product with respect to the temperature was measured, and the value of 2nd run was used as data.

(2) Evaluation of brittleness The two-layer tubular molded product was evaluated by rapidly bending it at an acute angle. When there was no crack, it was rated as O, when partially cracked, it was rated as C, and when it cracked, it was rated as X.

Reference Example 1 870 parts by weight of p-hydroxybenzoic acid, 168 parts by weight of 4,4'-dihydroxybiphenyl, 150 terephthalic acid
Parts by weight, 259 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g and 914 parts by weight of acetic anhydride were charged into a reaction vessel equipped with a stirring blade and a distillation tube, and deacetic acid polymerization was carried out under the following conditions. went.

First, 100 to 250 in a nitrogen gas atmosphere.
After reacting at 4 ° C. for 4 hours, the system was depressurized to 0.5 mmHg for 2 hours at 290 ° C., and the reaction was further continued for 1 hour.
When the polycondensation was completed, almost the theoretical amount of acetic acid flowed out, and a beige resin (A-
1) was obtained.

[0050]

[Chemical 9] k / l / m / n = 70/10/20/30 Reference Example 2 932 parts by weight of p-hydroxybenzoic acid, 210 parts by weight of 4,4′-dihydroxybiphenyl, 274 parts by weight of 2,6-diacetoxynaphthalene, anhydrous 1010 parts by weight of acetic acid and 374 parts by weight of terephthalic acid were charged into a reaction vessel equipped with a stirring blade and an outflow tube, and deacetic acid polymerization was carried out under the following conditions.

First, 100 to 250 in a nitrogen gas atmosphere.
After reacting at ℃ for 5 hours and at 250-330 ℃ for 1.5 hours, the pressure in the system is reduced to 0.5 mmHg at 310 ℃ for 1.5 hours, and the reaction is continued for 1.0 hour to complete polycondensation. As a result, almost theoretical amount of acetic acid was distilled off to obtain a beige resin (A-2) having the following structural formula.

[0052]

[Chemical 10] k / l / m / n = 75 / 12.5 / 12.5 / 25 Examples 1-5 Liquid crystalline polyester resin (a) (A-1 or A-2) and polybutylene terephthalate (b) (logarithmic viscosity 1 .01 dl
/ G) and an epoxy compound (d) having the following structure were weighed in predetermined amounts and dry-blended. It was melt-extruded with a 30 mmφ twin-screw extruder set at 270 to 300 ° C., cooled with water, pelletized, and dried.

[0053]

[Chemical 11] Next, 40 mmφ (Shinko Plastic Industry 40EX) and 25
mmφ (Plastic Engineering DT25T) two single-screw screws are connected with a die to enable extrusion molding into a two-layer tube.
40mm with the above pellet set to 230-240 ° C
Used for φ single screw, polybutylene terephthalate
(c) is subjected to a 25 mmφ single screw set to 240 to 250 ° C., extruded from a die having an outer diameter of 9 mmφ and an inner diameter of 8 mmφ, and a (A) layer composed of a liquid crystal polyester having an outer diameter of 6.0 mmφ and polybutylene terephthalate, Inner diameter 4.
Made of 8 mmφ polybutylene terephthalate (B)
A two-layer tubular molded body having layers and each layer having a thickness of 0.6 mm was formed. The moldability was good and the surface appearance was excellent. Further, the linear expansion coefficient and brittleness of this two-layer tubular molded body were evaluated by the above-mentioned methods. Table 1 shows the results.

Comparative Examples 1 and 2 The liquid crystal polyester resins (a) (A-1) of Reference Example 1, polybutylene terephthalate (b) and the epoxy compounds (d) used in Examples 1 to 5 were weighed in predetermined amounts. , Dry blended. It was melt-extruded with a 30 mmφ twin-screw extruder set at 270 to 300 ° C., cooled with water, pelletized, and dried. This was subjected to a 40 mmφ single screw set at 240 to 250 ° C. and extruded from a die having an outer diameter of 9 mmφ and an inner diameter of 8 mmφ to form a tubular molded body having an outer diameter of 6.0 mmφ and an inner diameter of 4.8 mmφ. Further, the linear expansion coefficient and brittleness of this tubular molded body were evaluated by the above-mentioned methods. Table 2 shows the results.

Comparative Example 3 Polybutylene terephthalate was applied to a 40 mmφ single screw set at 240 to 250 ° C. and the outer diameter was 9 mmφ.
It was extruded from a die having an inner diameter of 8 mmφ to form a tubular molded body having an outer diameter of 6.0 mmφ and an inner diameter of 4.8 mmφ. Further, the linear expansion coefficient and brittleness of this tubular molded body were evaluated by the above-mentioned methods. Table 2 shows the results.

Comparative Example 4 The liquid crystal polyester resin (a) (A-1) of Reference Example 1 was mixed with 28
A 40 mmφ single screw set at 0 to 290 ° C. was used to extrude from a die having an outer diameter of 9 mmφ and an inner diameter of 8 mmφ to form a tubular molded body having an outer diameter of 6.0 mmφ and an inner diameter of 4.8 mmφ. Further, the linear expansion coefficient and brittleness of this tubular molded body were evaluated by the above-mentioned methods. Table 2 shows the results.

Examples 6 to 8 Liquid crystalline polyester resin (a) (A-1), polybutylene terephthalate (b) (intrinsic viscosity 1.20 dl / g) and the epoxy compound (d) used in Examples 1 to 5 were used. A predetermined amount of each was weighed and dry blended. It was melt-extruded with a 30 mmφ twin-screw extruder set at 270 to 300 ° C., cooled with water, pelletized, and dried.

Using the same extruder as in Examples 1 to 5, the above pellets were subjected to a 20 mmφ single screw set to 230 to 240 ° C., and polybutylene terephthalate (c) was set to 240 to 250 ° C. 40 mmφ single screw. It is subjected to an axial screw and extruded from a die having an outer diameter of 9 mmφ and an inner diameter of 8 mmφ to form a layer (B) made of polybutylene terephthalate having an outer diameter of 6.0 mmφ and a layer (A) made of liquid crystal polyester having an inner diameter of 4.8 mmφ and polybutylene terephthalate And a two-layer tubular molded body having a thickness of 0.6 mm was molded.
The linear expansion coefficient and brittleness of this two-layer tubular molded body were evaluated by the above-mentioned methods. Table 1 shows the results.

[0059]

[Table 1]

[Table 2] From the results of Tables 1 and 2, the surface appearance can be obtained by forming a multilayer structure having a layer (A) composed of the liquid crystal polyester resin (a) and the thermoplastic resin (b) and a layer (B) composed of the thermoplastic resin (c). It can be seen that the toughness and linear expansion coefficient have been improved.

[0060]

The multilayer tubular molding according to the present invention has heat resistance,
Because of its excellent mechanical properties, toughness and surface appearance, it can be widely used in applications such as electric / electronic device parts, automobile parts, and mechanical parts.

Claims (7)

[Claims] 1. A liquid crystal polyester resin (a) and an anisotropic melt phase, which are composed of two or more layers including at least a layer (A) and a layer (B), and the layer (A) forms an anisotropic melt phase. A thermoplastic resin comprising a resin composition containing a thermoplastic resin (b) that does not form a layer, in which the layer (B) does not form an anisotropic molten phase
A multilayer tubular molded product comprising (c). 2. The multi-layer tubular body is a two-layer tubular body, comprising: (A)
The multilayer tubular molded article according to claim 1, wherein the layer is an outer layer and the layer (B) is an inner layer. 3. The layer (A) comprises 1 to 50% by weight of a liquid crystal polyester resin (a) which forms an anisotropic molten phase and 99 to 50% by weight of a thermoplastic resin (b) which does not form an anisotropic molten phase. The multilayer tubular molded product according to claim 1, which is composed of a resin composition which is contained. 4. A liquid crystal polyester resin (a) in which the layer (A) forms an anisotropic molten phase and a thermoplastic resin (b) which does not form an anisotropic molten phase in an amount of 99 to 50% by weight. Epoxy compound (d) to 100 parts by weight of the compound
The multilayer tubular molded product according to claim 1, which comprises a resin composition added with 0.01 to 20 parts by weight. 5. The multilayer tubular molded product according to claim 1, wherein the liquid crystal polyester resin (a) forming the anisotropic molten phase is a liquid crystal polyester resin comprising the following structural units (I) to (IV). Embedded image (However, R1 in the formula is R1 represents one or more groups selected from Represents one or more groups selected from In the formula, X represents a hydrogen atom or a chlorine atom, and the structural unit [(II) + (III)]
And the structural units (IV) are substantially equimolar. ) 6. A thermoplastic resin which does not form an anisotropic molten phase.
The multilayer tubular molding according to claim 1, wherein (b) is polybutylene terephthalate. 7. A thermoplastic resin which does not form an anisotropic molten phase.
The multilayer tubular molding according to claim 1, wherein (c) is polybutylene terephthalate.