JPH06917A - Double-layered tubular formed body - Google Patents

Abstract

PURPOSE:To enhance flexibility and durability by a method wherein double- layered tubular formed body consists of inner layer, which contains the specified percentage of polycarbodiimide in the specified polyester, and outer layer, the number average molecular weight and percentage content in the specified soft segment of which are respectively specified. CONSTITUTION:The double-layered tubular formed body consists of inner layer consisting of polyester composition, which contains 0.3-5 pts.wt. of polycarbodiimide to 100 pts.wt. of the specified polyester, and outer layer consisting of thermoplastic polyurethane elastomer having polyadipate and the like as soft segment, the number average molecular weight in which is 400-6,000 and the percentage content of which is 40-80wt.%. In this case, the specified polyester is mainly composed of aliphatic dicarboxylic acid represented by the general formula: HOOC-(CH2)n-COOH, aliphatic diol and dihydroxy compound represented by the separately shown general formula and the like. Further, the content and intrinsic viscosity of hydroxyl compound are respectively specified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layer tubular molded product which is excellent in flexibility and wear resistance and also in high temperature oil resistance.

[0002]

2. Description of the Related Art Elastomeric tubular moldings represented by hoses and tubes are widely used in many familiar fields such as daily necessities, automobiles and machines. Among them, tubular moldings used in mechanical equipment, automobiles, etc. The body is required to have high temperature oil resistance.

[0003] On the other hand, tubular molded articles made of thermoplastic elastomer are excellent in heat resistance and easy to mold, so that the demand thereof is expanding.

Japanese Unexamined Patent Publication (Kokai) No. 64-87973 discloses a tubular molded article in which a polyester elastomer is used to form a base layer, and a polyurethane elastomer is used to form a coating layer on the surface of the base layer. However, the tubular molded body does not have sufficient high temperature oil resistance.

[0005]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above-mentioned drawbacks, and an object thereof is to provide an elastomeric tubular molded article which is excellent in flexibility, abrasion resistance and high temperature oil resistance. Especially.

[0006]

The first tubular molded article of the present invention comprises a polyester (A) shown below and 0.3 to 5 parts by weight of polycarbodiimide based on 100 parts by weight of the polyester (A). And an inner layer made of a polyester composition containing at least one selected from the group consisting of polyadipate, polylactone, polycarbonate and polyol as a soft segment, and the soft segment portion has a number average molecular weight of 400 to 6000. And
An outer layer made of a thermoplastic polyurethane elastomer having a content of the soft segment of 40 to 80% by weight, thereby achieving the above object: (A) represented by the following general formula [I] An aliphatic dicarboxylic acid, an aliphatic diol, and at least one of a dihydroxy compound represented by the following general formula [II] and a monohydroxy compound represented by the following general formula [III] as main constituent components. Which has a hydroxy compound content of the dihydroxyl compound and the monohydroxy compound of 2 to 1 with respect to all monomers.
0 mol% and in o-chlorophenol at 30 ° C
A polyester having an intrinsic viscosity of 0.8 to 2.0 measured by.

[0007]

[Chemical 10]

(In the formula, n represents an integer of 0 to 10.)

[0009]

[Chemical 11]

(In the formula, R ¹ and R ² independently represent an alkylene group, p is 3 or 4, and q and r independently represent 0 or an integer of 1 or more.)

[0011]

[Chemical 12]

(In the formula, R ³ represents an alkylene group, and t is 2
Or 3, and m represents 0 or an integer of 1 or more. )
Further, the second tubular molded body of the present invention is shown below as a polyester component. 90 to 30 parts by weight of polyester (A) and polyester copolymer (B) 10 to 7 shown below.
0 parts by weight, and an inner layer made of a polyester copolymer composition containing 0.3 to 5.0 parts by weight of polycarbodiimide with respect to 100 parts by weight of the polyester component, polyadipate, polylactone, At least one selected from the group consisting of poly carbonate and polyol is a soft segment, the number average molecular weight of the soft segment portion is 400 to 6000, and the content of the soft segment is 40 to 80% by weight thermoplasticity An outer layer composed of a polyurethane elastomer is formed, and thereby the above-mentioned object is achieved: (A) An aliphatic dicarboxylic acid represented by the following general formula [I], an aliphatic diol, and the following general formula [II] ] A dihydroxy compound represented by the following and a monohydroxy compound represented by the following general formula [III] A polyester containing at least one of them as a main constituent component, wherein the content of the hydroxy compound in which the dihydroxyl compound and the monohydroxy compound are combined is 2 to 1 with respect to all the monomers.
0 mol% and in o-chlorophenol at 30 ° C
A polyester having an intrinsic viscosity of 0.8 to 2.0 as measured by;

[0013]

[Chemical 13]

(In the formula, n represents an integer of 0 to 10.)

[0015]

[Chemical 14]

(In the formula, R ¹ and R ² independently represent an alkylene group, p is 3 or 4, and q and r independently represent 0 or an integer of 1 or more.)

[0017]

[Chemical 15]

(In the formula, R ³ represents an alkylene group, and t is 2
Or 3, and m represents 0 or an integer of 1 or more. (B) An aromatic polyester segment containing an acid component containing terephthalic acid as a main component and a diol component containing at least one of ethylene glycol and butylene glycol as main components, and at least one of a lactone monomer and a polylactone. A polyester copolymer comprising an aliphatic segment obtained from one kind, wherein the content of the aliphatic segment is 20 to 70% by weight.
Is a polyester copolymer.

The third tubular molded article of the present invention has a polyester (A) 9 shown below as a polyester component.
0 to 30 parts by weight and 10 to 70 parts by weight of the polyester copolymer (C) shown below are added, and polycarbodiimide is added to 100 parts by weight of the polyester component in an amount of 0.
An inner layer composed of a polyester copolymer composition containing 3 to 5.0 parts by weight, polyadipate, polylactone,
At least one selected from the group consisting of poly carbonate and polyol is a soft segment, the number average molecular weight of the soft segment portion is 400 to 6000, and the content of the soft segment is 40 to 80% by weight thermoplasticity An outer layer composed of a polyurethane elastomer is formed, and thereby the above-mentioned object is achieved: (A) An aliphatic dicarboxylic acid represented by the following general formula [I], an aliphatic diol, and the following general formula [II] ] A dihydroxy compound represented by and a monohydroxy compound represented by the following general formula [III], and a polyester having at least one of the main components as a main constituent, wherein the dihydroxyl compound and the monohydroxy compound The total content of hydroxy compounds is 2 to 1 with respect to all monomers.
0 mol% and in o-chlorophenol at 30 ° C
A polyester having an intrinsic viscosity of 0.8 to 2.0 as measured by;

[0020]

[Chemical 16]

(In the formula, n represents an integer of 0 to 10.)

[0022]

[Chemical 17]

(In the formula, R ¹ and R ² independently represent an alkylene group, p is 3 or 4, and q and r independently represent 0 or an integer of 1 or more.)

[0024]

[Chemical 18]

(In the formula, R ³ represents an alkylene group, and t is 2
Or 3, and m represents 0 or an integer of 1 or more. ) (C) Aromatic polyester segment containing an acid component containing terephthalic acid as a main component and a diol component containing at least one of ethylene glycol and butylene glycol as a main component, and an acid containing terephthalic acid as a main component A polyester copolymer comprising a component and a polyester polyether segment having a diol component composed of an aliphatic polyalkylene oxide having a number average molecular weight of 400 to 6000 as a constituent, wherein the content ratio of the polyester polyether segment is 20 to 70% by weight of a polyester copolymer.

Next, the present invention will be described in detail.

First, the first multilayer tubular molding of the present invention will be described.

The multilayer tubular molding of the present invention has a polyester composition containing polyester (A) and polycarbodiimide as an inner layer.

The above polyester (A) comprises an aliphatic dicarboxylic acid represented by the above general formula [I], an aliphatic diol, a dihydroxy compound represented by the above general formula [II] and the above general formula [III]. The main constituent is at least one of the monohydroxy compounds represented by.

Examples of the aliphatic dicarboxylic acid represented by the above general formula [I] include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid and sebacic acid.

Examples of the above aliphatic diols include glycols and polyalkylene oxides.
Examples of the glycol include ethylene glycol, propylene glycol, trimethylene glycol,
1,4-butanediol, 1,3-butanediol,
1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, cyclopentane-1,2-diol , Cyclohexane-1,2-diol, cyclohexane-1,3-diol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol and the like. These may be used alone or in combination of two or more.

Examples of the above polyalkylene oxide include polyethylene oxide, polypropylene oxide, polytetramethylene oxide, polyhexamethylene oxide and the like. These may be used alone or in combination of two or more. The number average molecular weight of the polyalkylene oxide is preferably 100 to 20,000, and more preferably 100 to 20,000, because the ability to impart flexibility to the polyester produced decreases as the number average molecular weight decreases, and the physical properties such as thermal stability of the polyester produced decrease as the number increases. Is 5
It is from 00 to 5000.

In the dihydroxy compound represented by the above general formula [II], the alkylene groups R ¹ and R ² are preferably ethylene groups or propylene groups, and q and r are preferably 0 or 1. Examples of the dihydroxy compound [II] include 4,4 ″ -dihydroxy-p-terphenyl represented by the following formula [IV] and 4,4 ″ -dihydroxy-p-terphenyl represented by the following formula [V].
4 ′ ″-dihydroxy-p-quaterphenyl, 4,4 ′ ″-di (2-hydroxyethoxy) -p-quaterphenyl represented by the following formula [VI] are preferably used.

[0034]

[Chemical 19]

The melting point of 4,4 "-dihydroxy-p-terphenyl is 260 ° C, and the melting point of 4,4""-dihydroxy-p-quaterphenyl is 336 ° C.
The melting point of 4 ′ ″-di (2-hydroxyethoxy) -p-quaterphenyl is 403 ° C. In addition, 4,
4 '''-dihydroxy-p-quaterphenyl is
For example, Journal of Chemical Society, 1379-85 (1940)
It can be synthesized according to the method described in. The above dihydroxy compounds [II] may be used alone or in combination.

The dihydroxy compound [II] has high crystallinity, and as described above, 4,4 ″ -dihydroxy-p-terphenyl [IV] 4,4 ″ ′-dihydroxy-p-quaterphenyl [V] and Due to the high melting point of 4,4 ″ ′-di (2-hydroxyethoxy) -p-quaterphenyl [VI], when these dihydroxy compounds [II] are incorporated into the polymer chain, the polymer is It exhibits unique properties. That is, a strong physical crosslink is formed even when the content of the dihydroxy compound [II] is small. As a result, a thermoplastic elastomer having a high oil resistance and a high heat resistance, that is, a high temperature oil resistance is produced without impairing the flexibility derived from the soft segment.

The monohydroxy compound represented by the above general formula [III] is a rigid low molecular weight compound having a paraphenylene skeleton, and the melting point of these compounds is extremely high reflecting the characteristic molecular structure. Therefore, when the above-mentioned monohydroxy compound [III] is incorporated into the polymer terminal, it brings about very strong physical cross-linking, and has high oil resistance and heat resistance like the above dihydroxy compound [II], that is, high temperature oil resistance. It is presumed that a thermoplastic elastomer having excellent properties can be obtained.

In the above monohydroxy compound [III], R ³ is preferably an ethylene group or a propylene group, and m is preferably 0 or 1. Examples of the monohydroxy compound [III] include 4-hydroxy-p-
Examples thereof include terphenyl, 4-hydroxy-p-quaterphenyl, 4- (2-hydroxyethoxy) -p-terphenyl, 4- (2-hydroxyethoxy) -p-quaterphenyl and the like. These may be used alone or in combination.

The polyester (A) may contain a poly-silicone having two hydroxyl groups, a lactone and an aromatic hydroxycarboxylic acid as constituent components.

The above-mentioned polysilicone has two hydroxyl groups. Polysilicones having two hydroxyl groups at the ends of the molecule are preferable. For example, polydimethylsiloxane having two hydroxyl groups at both ends of the molecule, polydiethylsiloxane. Examples thereof include siloxane and polydiphenylsiloxane. When the number average molecular weight of the polysilicone is small, the ability to impart flexibility to the polyester produced is reduced, and when it is large, it becomes difficult to produce the polyester.
20000 is preferable, More preferably, it is 500-500.
It is 0.

The above-mentioned lactone is one which opens a ring and reacts with an acid and a hydroxyl group to add an aliphatic chain.
It preferably has one or more carbon atoms, more preferably a 5-membered to 8-membered ring, and examples thereof include ε-caprolactone, δ-valerolactone, γ-butyrolactone, enanthlactone and caprylolactone.

Examples of the aromatic hydroxycarboxylic acid include salicylic acid, metahydroxybenzoic acid, parahydroxybenzoic acid, 3-chloro-4-hydroxybenzoic acid, 3-bromo-4-hydroxybenzoic acid and 3-methoxy-. 4-hydroxybenzoic acid, 3-methyl-4-hydroxybenzoic acid, 3-phenyl-4-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, 4-hydroxy-4′-carboxybiphenyl and the like can be mentioned, preferably. Is para-hydroxybenzoic acid, 2-hydroxy-6-
Naphthoic acid, 4-hydroxy-4'-carboxybiphenyl.

Further, in order to improve the mechanical strength of the polyester and the like, the polyester may contain an aromatic diol and an aromatic dicarboxylic acid other than the dihydroxy compound [II] as constituent components.

Examples of the aromatic diol include hydroquinone, resorcin, chlorohydroquinone, bromohydroquinone, methylhydroquinone, phenylhydroquinone, methoxyhydroquinone, phenoxyhydroquinone, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybenzophenone, 4,4'-dihydroxydiphenylmethane, bisphenol A, 1,1-di (4-hydroxyphenyl)
Cyclohexane, 1,2-bis (4-hydroxyphenoxy) ethane, 1,4-dihydroxynaphthalene, 2,
Examples thereof include 6-dihydroxynaphthalene.

Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, metal salts of 5-sulfoisophthalic acid, 4,4'-dicarboxybiphenyl,
4,4'-dicarboxydiphenyl ether, 4,4 '
-Dicarboxydiphenyl sulfide, 4,4'-dicarboxydiphenyl sulfone, 3,3'-dicarboxybenzophenone, 4,4'-dicarboxybenzophenone, 1,2-bis (4-carboxyphenoxy) ethane, 1,4 -Dicarboxynaphthalene, or 2,6-
Examples include dicarboxynaphthalene.

Further, in the polyester (A) comprising the dihydroxy compound [II], the aliphatic diol and the aliphatic dicarboxylic acid, the oil resistance and the heat resistance are decreased when the content of the dihydroxy compound [II] is decreased, and the polyester (A) is increased. Since the elastic modulus becomes high and the flexibility decreases and it becomes unsuitable for use in an elastomer tubular molded article, the content of the above dihydroxy compound [II] is 2.0 to 2.0 in all monomers constituting the polyester (A). It is 10 mol%. When polyalkylene oxide or polysilicone is used as a diol other than aromatic, its constituent unit is counted as one monomer. That is, polyethylene oxide having a degree of polymerization of 10 is counted as 10 monomers.

Further, the above monohydroxy compound [II
I], an aliphatic diol, and a polyester (A) composed of an aliphatic dicarboxylic acid are monohydroxy compounds [II
When the content of [I] decreases, oil resistance and heat resistance decrease,
When the amount is large, the molecular weight of the polyester is not sufficiently increased and the physical properties are inferior. Therefore, the content of the above-mentioned monohydroxy compound [III] is 2.0 to 10 mol% in all monomers constituting the polyester. is there.

When the dihydroxy compound [II] and the monohydroxy compound [III] are used in combination, the dihydroxy compound [II] and the monohydroxy compound [II] are used.
When the content of the hydroxy compound combined with I) is low, the oil resistance and heat resistance are low, and when the content is high, the flexibility is low, and a sufficient increase in the molecular weight cannot be obtained. It is 2.0 to 10 mol% in all the monomers constituting the. At this time, the content ratio of the dihydroxy compound [II] and the monohydroxy compound [III] is preferably in the range satisfying 0 <[III] / [II] + [III] <2/3.

The intrinsic viscosity of the above polyester measured in o-chlorophenol at 30 ° C. is 0.8 to
It is 2.0. When it is less than 0.8, the high temperature oil resistance is insufficient, and when it is more than 2.0, molding becomes difficult.

The polyester composed of the above constituents can be produced by any of the following generally known polycondensation methods.

A method in which a dicarboxylic acid and a diol component (including an aliphatic diol, a dihydroxy compound, a monohydroxy compound, etc.) are directly reacted, and a lower ester of dicarboxylic acid and a diol component are reacted by transesterification. , A method of reacting a dicarboxylic acid halide with a diol component in a suitable solvent such as pyridine, a method of reacting a metal alcoholate of the diol component with a dicarboxylic acid halide, an acetyl component of the diol component and a dicarboxylic acid Examples of the method include a method of reacting with the use of transesterification.

In the polycondensation, a catalyst generally used in producing polyester may be used. As the catalyst, lithium, sodium, potassium, cesium, magnesium, calcium, barium, strontium, zinc, aluminum, titanium, cobalt, germanium, tin, lead, antimony, arsenic, cerium, boron, cadmium, manganese, and other metals, Examples thereof include organic metal compounds, organic acid salts, metal alkoxides and metal oxides.

Particularly preferred catalysts are calcium acetate, diacyl stannous tin, tetraacyl stannic tin, dibutyltin oxide, dibutyltin dilaurate, dimethyltin malate,
Tin dioctanoate, tin tetraacetate, triisobutyl aluminum, tetrabutyl titanate, germanium dioxide, and antimony trioxide. Two or more kinds of these catalysts may be used in combination. Further, various stabilizers may be used in order to improve thermal stability during polymerization.

The following stabilizers may be used in the polycondensation. 1,3,5-Trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 3,9-bis [2- [3- (3-t-butyl) -4-Hydroxy-5-methylphenyl) -propionyloxy] -1,1-dimethylethyl] 2,4,8,
In addition to hindered phenolic antioxidants such as 10-tetraoxaspiro [5,5] undecane, tris (2,4, di-t-butylphenyl) phosphite, trilaurylphosphite, 2-tert-butyl- α- (3-tert-butyl-4-hydroxyphenyl) -p-cumenylbis (p-nonylphenyl) phosphite, dimyristyl 3,3-thiodipropionate, distearyl 3,3-thiodipropionate, pentaerythyryl Examples of heat stabilizers include tetrakis- (3 lauryl thiopropionate) and ditridecyl 3,3-thiodipropionate.

Further, in order to efficiently distill off water, alcohol, glycol and the like, which are by-products of the polymerization, to obtain a high molecular weight polymer, the reaction system is set to 1 mmHg at the latter stage of the polymerization.
It is preferable to reduce the pressure below. The reaction temperature is generally 15
It is 0 to 350 ° C.

During the polymerization, the dihydroxy compound [II]
It is also possible to regulate the structure of the obtained polyester by changing the addition order of. For example, when the dihydroxy compound [II] is charged together with the dicarboxylic acid and other diol components, a block copolymer is easily obtained. Further, a polyester synthesized in advance is kneaded with the above-mentioned dihydroxy compound [II] or an acetylated product of the dihydroxy compound under reduced pressure heating, and a segment based on the dihydroxy compound [II] is introduced into the molecular chain by deethylene glycol or transesterification reaction. You can also

The polyester composition used for the inner layer of the multilayer tubular molded product of the present invention contains the above polyester (A) and polycarbodiimide. The polycarbodiimide is a polycarbodiimide having an average of 2 or more polycarbodiimides per molecule. These polycarbodiimides may be aliphatic, alicyclic, or aromatic, and include, for example, poly (tolylcarbodiimide), poly (4,4'-diphenylmethanecarbodiimide), poly (p-phenylenecarbodiimide), poly (m- Phenylenecarbodiimide), poly (1,3,5-triisopropylphenylene-2,4-carbodiimide), etc. The above polycarbodiimide may be used in combination of two or more. On the other hand, it is contained in an amount of 0.3% by weight to 5.0% by weight.When the content is less than 0.3% by weight, the heat resistance of the polyester composition is poor, and more than 5.0% by weight. And the physical properties of the polyester composition are poor.

By adding polycarbodiimide to the polyester (A), the heat resistance of the polyester composition is improved, and the molecular weight does not decrease even when the molded product is used at high temperature. This is because the polycarbodiimide reacts with the terminal carboxyl group of the polyester (A) to seal it, or connects two molecules of the polyester to extend the molecular difference, so that the decrease in molecular weight due to hydrolysis is suppressed. Presumed to be.

The polyester composition can be produced by a generally known method. Polyester (A),
As a method for uniformly mixing the polycarbodiimide, a melt kneading method using a plastomill, an extruder, a kneader, a Banbury mixer, or the like is performed.

The multi-layer tubular molding of the present invention has, as an outer layer, a thermoplastic polyurethane elastomer having a soft segment of at least one selected from the group consisting of polyadipate, polylactone, polycarbonate and polyol.

As the soft segment, a polyester or polyol having a hydroxyl group at the terminal selected from polyethylene adipate, polybutylene adipate, polylactone and polycarbonate is used. The number average molecular weight of the soft segment is 400 to 6000, and particularly preferably 800 to 3000. When the number average molecular weight is less than 400, impact resilience and flexibility of the thermoplastic polyurethane elastomer are insufficient. Further, when the number average molecular weight exceeds 6000, the mechanical strength of the thermoplastic polyurethane elastomer is insufficient. Further, the content ratio of the soft segment is 40 to 80% by weight. If the content is less than 40% by weight, the impact resilience and flexibility of the thermoplastic polyurethane elastomer will be insufficient. Further, if the content ratio exceeds 80% by weight, the mechanical strength of the thermoplastic polyurethane elastomer is insufficient.

The thermoplastic polyurethane elastomer contains a polymer chain composed of diisocyanate and short chain glycol as a hard segment.

As the above-mentioned isocyanate, for example,
4,4 ′ diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and the like can be mentioned, and the above-mentioned short chain glycols include ethylene glycol, 1,4-butanediol, bisphenol A and the like.

The thermoplastic polyurethane elastomer has good bending resistance, abrasion resistance and flexibility.

The multi-layer tubular molded article can be molded by a two-layer coextrusion method to form a multi-layer tubular molded article comprising a polyester composition as an inner layer and a thermoplastic polyurethane elastomer as an outer layer, or two extruders. There is a method of first molding the polyester composition as the inner layer and then extruding the thermoplastic polyurethane elastomer as the outer layer.

A single-screw or twin-screw extruder is used for extrusion. Since the temperature control of the barrel is important, it is preferable that the heater is divided into three or more regions. In particular, those equipped with a cooling system are preferable. Also,
L / D of the screw portion is preferably about 20 to 25.
Further, in order to prevent decomposition during molding, the polyester composition is molded after being sufficiently dried. The molding temperature of the polyester composition depends on the composition, but is 170 to 170 on the hopper side of the barrel.
240 ° C., 180 to 265 ° C. in the middle part and the tip part, and the die temperature is preferably 170 to 250 ° C.

The molding temperature of the thermoplastic polyurethane elastomer is 150 to 175 ° C. on the hopper side of the barrel, 165 to 195 ° C. on the middle portion and the tip portion, and the die temperature is preferably about 170 to 210 ° C.

Next, the second multilayer tubular molding of the present invention will be described.

The multilayer tubular molding of the present invention has a polyester copolymer composition containing the polyester (A), the polyester copolymer (B) and polycarbodiimide as the inner layer.

The above polyester (A) is the same as that described for the first multilayer tubular molding.

The above polyester copolymer (B) is an aromatic polyester containing an acid component containing terephthalic acid as a main component and a diol component containing at least one of ethylene glycol and butylene glycol as a main component. It is obtained by reacting at least one of a lactone monomer and a polylactone.

In the above aromatic polyester, the butylene glycol used as the diol component is
Either 1,4-butanediol or 1,3-butanediol can be used.

In addition to the above-mentioned aromatic polyesters, aliphatic glycols other than the above, polyalkylene oxides, polysilicones having two hydroxyl groups, aromatic diol components, aromatic dicarboxylic acids other than terephthalic acid, and aromatic hydroxylcarboxylic acids. , And an aliphatic dicarboxylic acid may be contained as constituent components, and the content thereof is preferably 10 mol% or less of the total amount of the diol component and the acid component.

Examples of the above glycol include propylene glycol, 1,5-pentanediol, 1,6-
Hexanediol, 1,7-heptanediol, 1,8
-Octanediol, 1,9-nonanediol, 1,1
0-decanediol, cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,3-diol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, 4,
4 ″ -di (2-hydroxyethoxy) -p-terphenyl, 4,4 ′ ″-di (2-hydroxyethoxy)-
Examples thereof include p-quaterphenyl.

Examples of the polyalkylene oxide include those used for the polyester (A). These may be used alone or in combination of two or more. When the number average molecular weight of the polyalkylene oxide is small, the ability to impart flexibility to the resulting aromatic polyester is reduced, and when it is large, physical properties such as thermal stability of the resulting aromatic polyester are reduced.
0 to 20000 is preferable, and 500 to 5 is more preferable.
It is 000.

The above-mentioned polysilicone has two hydroxyl groups, and a polysilicone having two hydroxyl groups at the molecular ends is preferable, and examples thereof include those used for the polyester (A). The number average molecular weight of the polysilicone is preferably 100 to 20,000, and more preferably 500 to 20,000, because the ability to impart flexibility to the aromatic polyester produced decreases as the number average molecular weight decreases, and the production of the aromatic polyester becomes difficult when the number increases. It is 5000.

Examples of the above aromatic diols include hydroquinone, resorcin, chlorohydroquinone, bromohydroquinone, methylhydroquinone, phenylhydroquinone, methoxyhydroquinone, phenoxyhydroquinone, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybenzophenone, 4,4'-dihydroxydiphenylmethane, bisphenol A, 1,1-di (4-hydroxyphenyl)
Cyclohexane, 1,2-bis (4-hydroxyphenoxy) ethane, 1,4-dihydroxynaphthalene, 2,
6-dihydroxynaphthalene, 4,4 ″ -dihydroxy-p-terphenyl, 4,4 ′ ″-dihydroxy-
An example is p-quarterphenyl.

Examples of the aromatic dicarboxylic acid include isophthalic acid, metal salts of 5-sulfoisophthalic acid,
4,4'-dicarboxybiphenyl, 4,4'-dicarboxydiphenyl ether, 4,4'-dicarboxydiphenyl sulfide, 4,4'-dicarboxydiphenyl sulfone, 3,3'-dicarboxybenzophenone, 4,4 '-Dicarboxybenzophenone, 1,2-
Examples thereof include bis (4-carboxyphenoxy) ethane, 1,4-dicarboxynaphthalene, and 2,6-dicarboxynaphthalene.

The above-mentioned aromatic hydroxycarboxylic acid imparts rigidity and liquid crystallinity to the aromatic polyester,
For example, the polyester (A) used may be used.

The aliphatic dicarboxylic acid is preferably a dicarboxylic acid having 10 or less carbon atoms, and examples thereof include those used in the polyester (A). When a dicarboxylic acid having a carbon number of more than 10 is used, the physical properties of the obtained molded product will deteriorate.

The aromatic polyester comprising the above constituents can be produced by any generally known polycondensation method used for producing the polyester (A).

In the polycondensation, a catalyst generally used in producing polyester can be used. For example, a catalyst used when producing the above polyester (A) is used. These catalysts may be used in combination of two or more kinds. Also, in order to improve thermal stability during polymerization,
Various stabilizers may be used.

Further, in order to efficiently distill off water, alcohol, glycol and the like, which are by-products of the polymerization, to obtain a high molecular weight polymer, the reaction system is set to 1 mmHg at the latter stage of the polymerization.
It is preferable to reduce the pressure below. The reaction temperature is generally 15
It is 0 to 350 ° C.

The lactone monomer is preferably one that opens a ring and reacts with an acid and a hydroxyl group to add an aliphatic chain, and has 4 or more carbon atoms in the ring, more preferably Is a 5-membered to 8-membered ring, for example,
Examples include ε-caprolactone, δ-valerolactone, γ-butyrolactone, enanthlactone, caprylolactone and the like. Two or more lactone monomers may be used in combination.

The polylactone is for transesterifying with the aromatic polyester to add an aliphatic chain, and imparts flexibility to the polyester copolymer.
A polylactone obtained by ring-opening polymerization of a lactone monomer having 4 or more carbon atoms in the ring is preferable, and a polylactone obtained from a 5-membered to 8-membered lactone monomer monomer is more preferable. For example, ε-caprolactone, δ-valerolactone, enanthlactone,
Examples thereof include polylactone polymerized from caprilactone and the like. It may be a polylactone composed of two or more kinds of lactone monomers. Further, a lactone monomer and a polylactone may be used in combination.

The composition ratio between the aromatic polyester and the lactone compound (lactone monomer and / or polylactone) is such that the weight ratio of the aromatic polyester / lactone compound is 30/70 from the viewpoint of the elastic properties of the obtained polyester copolymer. -80/20 is preferable, and a particularly preferable range is 40 / 60-70 / 30.

For the reaction of the aromatic polyester and the lactone monomer, the catalyst used for producing the polyester (A) may be used. When the reaction is carried out in a solvent-free system, the reaction temperature is usually a temperature at which the mixture of the aromatic polyester and the lactone monomer is uniformly melted, and a temperature not lower than the melting point of the block copolymer produced. When the aromatic polyester and the lactone monomer are reacted in a solution system, the reaction temperature can be appropriately selected. 180 ° C in general
The range of ˜300 ° C. is preferred. If it is less than 180 ° C, it is difficult for the aromatic polyester to uniformly dissolve with the lactone monomer,
Above 300 ° C, decomposition and other undesirable side reactions occur. Further, the solvent used when the above reaction is carried out as a solution needs to be a common solvent for the aromatic polyester and the lactone monomer. For example, α-methylnaphthalene can be adopted.

The transesterification reaction between the aromatic polyester and the polylactone proceeds without a catalyst, but the catalyst used for producing the polyester (A) may be used. At this time, a stabilizer used for producing the polyester (A) may be added. The reaction temperature is usually a temperature at which the mixture of the aromatic polyester and the polylactone melts uniformly, and a temperature not lower than the melting point of the block copolymer produced. Generally, the range of 180 ° C to 300 ° C is preferable. 18
If the temperature is lower than 0 ° C, the aromatic polyester is difficult to uniformly dissolve with the polylactone, and if it exceeds 300 ° C, decomposition or other undesirable side reaction occurs.

For the transesterification reaction, a polymerization apparatus usually used for polymerizing polyester is preferably used. Also,
It is also possible to carry out transesterification between the aromatic polyester and the polylactone in an extruder or a kneader.

The polyester copolymer composition used in the multi-layer tubular molding of the present invention contains, as the polyester component,
90 to 30 parts by weight of polyester (A) and 10 to 70 parts by weight of polyester copolymer (B), preferably 80 to 40 parts by weight of polyester (A) and 20 to 60 parts by weight of polyester copolymer (B), and The polyester component 1
Polycarbodiimide in an amount of 0.3-5.
It is obtained by uniformly mixing 0 parts by weight. When the amount of the polyester copolymer (B) is less than 10 parts by weight, the mechanical strength of the obtained polyester copolymer composition at high temperature is insufficient, and when the amount of the polyester copolymer (B) exceeds 70 parts by weight, the polyester copolymer (B) is Polymer compositions lack flexibility and high temperature oil resistance.

By incorporating the above polycarbodiimide into the above polyester copolymer composition (B), the heat resistance of this polyester copolymer composition is improved, and the molded polyester copolymer is used at high temperature. However, the molecular weight does not decrease. This is because polycarbodiimide reacts with the terminal carboxyl group of polyester and seals it.
Alternatively, it is presumed that since two molecules of polyester are connected to extend the molecular difference, the decrease in molecular weight due to hydrolysis is suppressed. The polycarbodiimide is a polycarbodiimide having an average of 2 or more polycarbodiimides per molecule. These polycarbodiimides may be aliphatic, alicyclic or aromatic. For example, those described for the first multilayer tubular molded body can be mentioned. Two or more polycarbodiimides may be used in combination.

The polycarbodiimide is contained in a proportion of 0.3% by weight to 5.0% by weight based on the total polyester components. If the content is less than 0.3% by weight, the heat resistance of the polyester copolymer composition is poor, and if it exceeds 5.0% by weight, the physical properties of the polyester copolymer composition are poor.

The above polyester copolymer composition can be produced by a generally known method. As a method for uniformly mixing the polyester (A), the polyester copolymer (B) and the polycarbodiimide, a melt kneading method using a plastomill, an extruder, a kneader, a Banbury mixer or the like is performed.

The multi-layer tubular molded product of the present invention has, as an outer layer, a thermoplastic polyurethane elastomer having a soft segment of at least one selected from the group consisting of polyadipate, polylactone, polycarbonate and polyol.

As the soft segment, a polyester or polyol having a hydroxyl group at the terminal selected from polyethylene adipate, polybutylene adipate, polylactone and polycarbonate is used. The number average molecular weight of the soft segment is 400 to 6000, and particularly preferably 800 to 3000. When the number average molecular weight is less than 400, impact resilience and flexibility of the thermoplastic polyurethane elastomer are insufficient. Further, when the number average molecular weight exceeds 6000, the mechanical strength of the thermoplastic polyurethane elastomer is insufficient. Further, the content ratio of the soft segment is 40 to 80% by weight. If the content is less than 40% by weight, the impact resilience and flexibility of the thermoplastic polyurethane elastomer will be insufficient. Further, if the content ratio exceeds 80% by weight, the mechanical strength of the thermoplastic polyurethane elastomer is insufficient.

The thermoplastic polyurethane elastomer contains a polymer chain composed of diisocyanate and short chain glycol as a hard segment.

Examples of the above-mentioned diisocyanate and the above-mentioned short-chain glycol include those described for the first multilayer tubular molding.

The above-mentioned thermoplastic polyurethane elastomer has good flex resistance, abrasion resistance and flexibility.

The multi-layer tubular molded article can be molded by a two-layer coextrusion method to form a multi-layer tubular molded article comprising a polyester composition as an inner layer and a thermoplastic polyurethane elastomer as an outer layer, or two extruders. There is a method of first molding the polyester composition as the inner layer and then extruding the thermoplastic polyurethane elastomer as the outer layer.

A single-screw or twin-screw extruder is used for extrusion. Since the temperature control of the barrel is important, it is preferable that the heater is divided into three or more regions. In particular, those equipped with a cooling system are preferable. Also,
L / D of the screw portion is preferably about 20 to 25.
Further, in order to prevent decomposition during molding, the polyester composition is molded after being sufficiently dried. The molding temperature of the polyester composition depends on the composition, but is 170 to 170 on the hopper side of the barrel.
240 ° C., 180 to 265 ° C. in the middle part and the tip part, and the die temperature is preferably 170 to 250 ° C.

The molding temperature of the thermoplastic polyurethane elastomer is 150 to 175 ° C. on the hopper side of the barrel, 165 to 195 ° C. on the middle portion and the tip portion, and the die temperature is preferably about 170 to 210 ° C.

Next, the third multi-layer tubular molding of the present invention will be described.

The multilayer tubular molding of the present invention has a polyester copolymer composition containing the polyester (A), the polyester copolymer (C) and polycarbodiimide as the inner layer.

The above polyester (A) is the same as that described for the first multilayer tubular molding.

The polyester copolymer (C) is an aromatic polyester segment containing an acid component containing terephthalic acid as a main component and a diol component containing at least one of ethylene glycol and butylene glycol as main components. And a polyester polyether segment containing an acid component containing terephthalic acid as a main component and a diol component containing an aliphatic polyalkylene oxide having a number average molecular weight of 400 to 6000 as constituent components.

Examples of the aromatic polyester segment include those described for the second multilayer tubular molding.

Examples of the aliphatic polyalkylene oxide include those used in the polyester (A). These may be used alone or in combination of two or more. If the number average molecular weight of the polyalkylene oxide is less than 400, the ability to impart flexibility to the resulting polyester copolymer is reduced, resulting in 6000.
If it exceeds, physical properties such as thermal stability of the resulting polyester deteriorate.

The content ratio of the polyester polyether segment is 20 to 70% by weight. If the amount is less than 20% by weight, the polyalkylene oxide unit, which is a low Tg component of the polymer, is reduced, so that the low temperature characteristics of the polyester copolymer cannot be improved and the amount is 70% by weight.
If it exceeds the range, good mechanical properties of the polyester copolymer cannot be obtained.

The polyester copolymer (C) comprising the above-mentioned constituents can be produced by any generally known polycondensation method used for producing the polyester (A). You can

When the polyalkylene oxide is reacted, it is added in the latter stage of the polymerization of the aromatic polyester mainly composed of the diol component mainly containing ethylene glycol and / or butylene glycol and the acidic component mainly containing terephthalic acid. Or a method of reacting by utilizing transesterification after polymerization of an aromatic polyester having a diol component mainly containing ethylene glycol and / or butylene glycol and an acidic component mainly containing terephthalic acid as constituent components. Any method may be used.

The polyester copolymer composition of the present invention comprises
90 to 30 parts by weight of polyester (A) and 10 to 70 parts by weight of polyester copolymer (C), preferably
It is obtained by uniformly mixing 0.3 to 5.0 parts by weight of polycarbodiimide with 100 to 40 parts by weight of (A) and 20 to 60 parts by weight of (C), and 100 parts by weight of all polyester components. When the polyester copolymer (C) is less than 10 parts by weight, the mechanical strength of the obtained polyester copolymer composition at high temperature is insufficient, and when the polyester copolymer (C) exceeds 70 parts by weight, the polyester copolymer (C) is Polymer compositions lack flexibility and high temperature oil resistance.

By incorporating the above polycarbodiimide into the above polyester copolymer composition (C), the heat resistance of this polyester copolymer composition is improved, and the molded polyester copolymer is used at high temperature. However, the molecular weight does not decrease. This is because polycarbodiimide reacts with the terminal carboxyl group of polyester and seals it.
Alternatively, it is presumed that since two molecules of polyester are connected to extend the molecular difference, the decrease in molecular weight due to hydrolysis is suppressed. The polycarbodiimide is a polycarbodiimide having an average of 2 or more polycarbodiimides per molecule. These polycarbodiimides may be aliphatic, alicyclic or aromatic. For example, those described for the first multilayer tubular molded body can be mentioned. Two or more polycarbodiimides may be used in combination.

The polycarbodiimide is contained in a proportion of 0.3% by weight to 5.0% by weight based on the total polyester components. If the content is less than 0.3% by weight, the heat resistance of the polyester copolymer composition is poor, and if it exceeds 5.0% by weight, the physical properties of the polyester copolymer composition are poor.

The above polyester copolymer composition can be produced by a generally known method. As a method for uniformly mixing the polyester (A), the polyester copolymer (C) and the polycarbodiimide, plastomil,
A melt-kneading method using an extruder, a kneader, a Banbury mixer or the like is performed.

The multi-layer tubular molding of the present invention has, as an outer layer, a thermoplastic polyurethane elastomer having a soft segment of at least one selected from the group consisting of polyadipate, polylactone, polycarbonate and polyol.

As the soft segment, a polyester or polyol having a hydroxyl group at the terminal selected from polyethylene adipate, polybutylene adipate, polylactone and polycarbonate is used. The number average molecular weight of the soft segment is 400 to 6000, and particularly preferably 800 to 3000. When the number average molecular weight is less than 400, impact resilience and flexibility of the thermoplastic polyurethane elastomer are insufficient. Further, when the number average molecular weight exceeds 6000, the mechanical strength of the thermoplastic polyurethane elastomer is insufficient. Further, the content ratio of the soft segment is 40 to 80% by weight. If the content is less than 40% by weight, the impact resilience and flexibility of the thermoplastic polyurethane elastomer will be insufficient. Further, if the content ratio exceeds 80% by weight, the mechanical strength of the thermoplastic polyurethane elastomer is insufficient.

The thermoplastic polyurethane elastomer contains a polymer chain composed of diisocyanate and short chain glycol as a hard segment.

Examples of the above-mentioned isocyanate and the above-mentioned short-chain glycol include those described for the first multilayer tubular molding.

The thermoplastic polyurethane elastomer has good bending resistance, abrasion resistance and flexibility.

The method for forming the multi-layer tubular molded article may be a two-layer coextrusion method for forming a multi-layer tubular molded article comprising a polyester composition as the inner layer and a thermoplastic polyurethane elastomer as the outer layer, or two extruders. There is a method of first molding the polyester composition as the inner layer and then extruding the thermoplastic polyurethane elastomer as the outer layer.

A uniaxial or biaxial extruder is used for extrusion. Since the temperature control of the barrel is important, it is preferable that the heater is divided into three or more regions. In particular, those equipped with a cooling system are preferable. Also,
L / D of the screw portion is preferably about 20 to 25.
Further, in order to prevent decomposition during molding, the polyester composition is molded after being sufficiently dried. The molding temperature of the polyester composition depends on the composition, but is 170 to 170 on the hopper side of the barrel.
240 ° C., 180 to 265 ° C. in the middle part and the tip part, and the die temperature is preferably 170 to 250 ° C.

The molding temperature of the thermoplastic polyurethane elastomer is 150 to 175 ° C. on the hopper side of the barrel, 165 to 195 ° C. on the middle portion and the tip portion, and the die temperature is preferably about 170 to 210 ° C.

[0123]

EXAMPLES Next, the present invention will be described with reference to examples.

(Synthesis of Polyester (A)) 2925 g (20 mol) of adipic acid, ethylene glycol 298
0 g (48 mol) and 4,4 ′ ″-dihydroxy-p-quarter-phenyl (hereinafter referred to as DHQ) 5
08 g (2 mol) of the monomer mixture, 2 g of germanium dioxide as a catalyst and 1,3,5-
Trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene 4 g, tris (2,4-di-t-butylphenyl) phosphite 4 g
Was added, and the mixture was kept under nitrogen at 200 ° C. for 2 hours to carry out an esterification reaction. Next, the reaction system is heated to 320 ° C. for 30 minutes.
The temperature was raised up to, and this state was maintained for 20 minutes at normal pressure. Then, the temperature was lowered to 300 ° C., and the polycondensation reaction was carried out for 2 hours under a reduced pressure of 1 mmHg or less, whereby a light yellow resin was obtained.

When the intrinsic viscosity of the obtained polyester was measured in an o-chlorophenol at 30 ° C. using an Ubbelohde viscometer, [η] = 1.20. The Shore D hardness was 28.

The polyester obtained here is referred to as (A).

(Synthesis of Polyester Copolymer (B)) (1) Synthesis of Aromatic Polyester In a reaction vessel equipped with a stirrer, a thermometer, a gas blowing port and a distillation port, 19.4 kg of dimethyl terephthalate and 20 of butylene glycol. 0.2 kg, a small amount of calcium acetate and tetrabutyl titanate as a catalyst were added. After replacing the inside of the reaction vessel with nitrogen, the temperature was raised and the reaction was carried out at 180 ° C. for 3 hours. With the reaction, methanol begins to distill,
Bis (2-hydroxybutyl) terephthalate was obtained.

Next, the temperature of this reaction vessel was raised to 250 ° C., the distillation port was connected to a vacuum vessel, and the reaction was performed for 2 hours while the pressure inside the reaction vessel was reduced to 1 mmHg. Butylene glycol was distilled out along with the reaction, and an extremely viscous liquid was produced in the flask. The product was recovered by pouring it into water and quenching.

(2) Synthesis of polyester copolymer (B) In a reaction vessel equipped with a stirrer, thermometer, gas blowing port and distillation port, 35 kg of the above aromatic polyester, ε-
Caprolactone 15 kg, tetrabutyl titanate 100 g as a catalyst, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4) as a heat stabilizer.
100 g of -hydroxybenzyl) benzene were added. After replacing the inside of the reaction vessel with nitrogen, the mixture was heated to 240 ° C. in an oil bath while stirring. The reaction system became a uniform and viscous liquid.

Then, after reacting for 1 hour under a nitrogen stream, the gas inlet was connected to a vacuum pump, and the reaction was further continued for 1 hour while the pressure inside the reaction vessel was reduced to 1 mmHg.

The Shore D hardness of the obtained polymer is 57.
And had rubber-like elasticity.

The polyester copolymer obtained here is referred to as (B).

(Synthesis of Polyester Copolymer (C)) In a reaction vessel equipped with a stirrer, a thermometer, a gas blowing port and a distillation port, 19.4 kg of dimethyl terephthalate, 13.2 kg of butylene glycol and polytetramethylene oxide ( Number average molecular weight 980) 13 kg, a small amount of magnesium acetate and tetrabutyl titanate as a catalyst, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-) as a heat stabilizer. 115 g of hydroxybenzyl) benzene and tris (2,4-di-t-)
115 g of butylphenyl) phosphite were added. After replacing the inside of the reaction vessel with nitrogen, the temperature was raised to 250 ° C. over 2 hours and the reaction was performed for 1.5 hours. With the reaction, methanol was distilled off.

Next, the distillation port of this reaction vessel was connected to a vacuum vessel, the pressure inside the reaction vessel was reduced to 0.3 mmHg over 20 minutes, and the reaction was performed for 1.5 hours in that state. Butylene glycol was distilled out along with the reaction, and an extremely viscous liquid was produced in the reaction vessel. The product was recovered by pouring it into water and quenching.

The Shore D hardness of the obtained polymer was 60.

The polyester copolymer obtained here is designated as (C).

(Synthesis of Polyurethane (1)) 4,4'-
Diphenylene methane diisocyanate (MDI) 550
g (2.2 mol), polytetramethylene oxide glycol (number average molecular weight 1500) 1500 g (1 mo
l) and 90.12 g of 1,4-butylene glycol
(1 mol) was charged in a glass container, and a nitrogen stream was added to 70
After reacting for 3 hours at 120 ° C. and then for 10 hours at 120 ° C., a white elastic body was formed.

The obtained resin had a Shore D hardness of 83 and a tensile strength at break of 400 kg / cm ² .

The polyurethane obtained here is referred to as (1).

(Synthesis of Polyurethane (2)) Polyurethane was obtained in the same manner as in the synthesis of polyurethane (1) except that polycaprolactone (terminal hydroxyl group, number average molecular weight 1500) was used instead of polytetramethylene oxide glycol. .

The Shore D hardness of the obtained polyurethane is 8
2 and the tensile strength at break was 380 kg / cm ² .

The polyurethane obtained here is referred to as (2).

(Synthesis of Polyurethane (3)) A polyurethane was obtained in the same manner as in the synthesis of Polyurethane (1) except that polybutylene adipate (terminal hydroxyl group, number average molecular weight 1500) was used instead of polytetramethylene oxide glycol. It was

The Shore D hardness of the obtained polyurethane is 8
3, the tensile strength at break was 390 kg / cm ² .

The polyurethane obtained here is referred to as (3).

Example 1 Polyester (A) 10 was added to the above polyester (A).
Poly (1,3,5-triisopropylphenylene-2,4-as polycarbodiimide based on 0 part by weight)
Carbodiimide) (Sumitomo Bayer Urethane Co., Ltd., Starvacol P-100) (2 parts by weight) was added, and 3,9-bis [2- [3] was added as a hindered phenol antioxidant.
-(3-t-Butyl-4-hydroxy-5-methylphenyl) -propionyloxy] -1,1-dimethylethyl] 2,4,8,10-tetraoxaspiro [5,5]
0.2 parts by weight of undecane and 0.32 parts by weight of pentaerystyryl tetrakis- (3 lauryl thiopropionate) as a sulfur-based antioxidant were added, and the mixture was extruded at 240 ° C. by using a Bender Plastograph extruder to obtain polyester. A composition was obtained.

This composition was processed by a uniaxial extruder to obtain an inner diameter of 2
It was extruded using a hose mold having an outer diameter of 0 mm and a diameter of 22 mm to form a polyester composition as an inner layer. The molding temperature was 240 ° C. for the mold and 235 to 240 ° C. for the cylinder part. Next, the inner layer was continuously passed through a hose mold having an inner diameter of 24 mm and an outer diameter of 26 mm, and the polyurethane (1) was extruded as an outer layer. Molding temperature is 170-175 for mold
C., and the cylinder portion was 165 to 170.degree. Thus, a multilayer hose having the polyester composition as the inner layer and the thermoplastic polyurethane as the outer layer was obtained.

Example 2 and Example 3 A multilayer hose was obtained in the same manner as in Example 1 except that polyurethane (2) and polyurethane (3) were used instead of polyurethane (1).

Comparative Example 1 From the polyester composition obtained in Example 1, an inner diameter of 20
A single-layer hose was obtained using a hose mold having an outer diameter of 22 mm. Molding temperature is 240 ℃ for the mold and 23 for the cylinder.
It was set to 5 to 240 ° C.

Example 4 A multilayer hose was obtained in the same manner as in Example 1 except that the above polyester (A) and the above polyester copolymer (B) were used in the proportions shown in Table 1.

Comparative Example 2 A single-layer hose was obtained from the polyester copolymer composition obtained in Example 4 in the same manner as in Comparative Example 1.

Example 5 A multilayer hose was obtained in the same manner as in Example 2 except that the above polyester (A) and the above polyester copolymer (B) were used in the proportions shown in Table 1.

Example 6 A multilayer hose was obtained in the same manner as in Example 3 except that the above polyester (A) and the above polyester copolymer (B) were used in the proportions shown in Table 1.

Comparative Example 3 A single-layer hose was obtained from the polyester copolymer composition obtained in Example 5 in the same manner as in Comparative Example 1.

Example 7 A multilayer hose was obtained in the same manner as in Example 1 except that the above polyester (A) and the above polyester copolymer (C) were used in the proportions shown in Table 1.

Comparative Example 4 A single-layer hose was obtained from the polyester copolymer composition obtained in Example 7 in the same manner as in Comparative Example 1.

(Oil resistance test) The hoses obtained in Examples 1 to 4 and Comparative Examples 1 to 4 were cut into a length of 20 cm, and J
After filling IS3 oil inside the hose, both sides were sealed with silicone stoppers and allowed to stand in a gear oven at 120 ° C. Fifty
After a day, cool the hose to room temperature and drain the oil.
It was bent so that the inner layer of the cutout resin had a height of 5 cm and a length of 5 cm, and the occurrence of cracks was observed with a 10 × magnifying glass. The results are shown in Table 1.

(Abrasion resistance test) The hoses obtained in Examples 1 to 4 and Comparative Examples 1 to 4 were cut out to a width of 1 cm and a length of 5 cm to prepare test pieces. This test piece was fixed to a test stand, and a wear test was performed using CS-17 and H-22 wear wheels (load 1 kg). The rotation speed of the worn wheel was tested 60 times / minute and 1000 times. The amount of resin scraped off was measured. The results are shown in Table 1.

[0159]

[Table 1]

[0160]

According to the present invention, a polyester having a certain molecular weight or more, in which a segment based on a dihydroxy compound or a monohydroxy compound having a high crystallinity and a high melting point is introduced, and a polyester having terephthalic acid as a main acidic component are used. A multi-layered tubular molded article composed of a polymer and an inner layer made of a composition containing polycarbodiimide, and a thermoplastic polyurethane elastomer as an outer layer is obtained. The multi-layered tubular molded article is flexible and has high temperature oil resistance. It is a multi-layer tubular molded product that is excellent and has excellent wear resistance.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location // C08G 18/42 NDW 8620-4J C08L 75/04 NGJ 8620-4J (C08L 67/02 79: 04) (72) Inventor Daishiro Kishimoto 2-11-20 Mishimaoka, Ibaraki City, Osaka Prefecture

Claims (3)

[Claims] 1. An inner layer comprising a polyester composition containing the following polyester (A) and 0.3 to 5 parts by weight of polycarbodiimide with respect to 100 parts by weight of the polyester (A); At least one selected from the group consisting of adipate, polylactone, polycarbonate and polyol is used as a soft segment, and the soft segment portion has a number average molecular weight of 400 to 600.
0, and the content ratio of the soft segment is 40 to 80.
A multi-layered tubular molded article composed of an outer layer made of a thermoplastic polyurethane elastomer in a weight percentage of: (A) an aliphatic dicarboxylic acid represented by the following general formula [I], an aliphatic diol, and the following general formula: A polyester mainly composed of a dihydroxy compound represented by [II] and at least one of a monohydroxy compound represented by the following general formula [III], wherein the dihydroxyl compound and the monohydroxy compound The content of the hydroxy compound including the compound is 2 to 1 with respect to all the monomers.
0 mol% and in o-chlorophenol at 30 ° C
A polyester having an intrinsic viscosity of 0.8 to 2.0 measured by. [Chemical 1] (In the formula, n represents an integer of 0 to 10.) (In the formula, R ¹ and R ² independently represent an alkylene group,
p is 3 or 4, q and r each independently represent 0 or an integer of 1 or more. ) [Chemical 3] (In the formula, R ³ represents an alkylene group, t is 2 or 3, and m is 0 or an integer of 1 or more.) 2. A polyester component comprising 90 to 30 parts by weight of a polyester (A) shown below and 10 to 70 parts by weight of a polyester copolymer (B) shown below, and 100 parts by weight of the polyester component. On the other hand, an inner layer made of a polyester copolymer composition containing 0.3 to 5.0 parts by weight of polycarbodiimide, and a polyadipate,
At least one selected from the group consisting of polylactone, polycarbonate and polyol is used as the soft segment, and the number average molecular weight of the soft segment is 40.
A multi-layered tubular molded product having an outer layer consisting of a thermoplastic polyurethane elastomer having a soft segment content of 0 to 6000 and a soft segment content of 40 to 80% by weight: (A) represented by the following general formula [I]: And a dihydroxy compound represented by the following general formula [II] and / or at least one kind of a monohydroxy compound represented by the following general formula [III]. A polyester as a component, wherein the content of the hydroxy compound in which the dihydroxyl compound and the monohydroxy compound are combined is 2 to 1 with respect to all the monomers.
0 mol% and in o-chlorophenol at 30 ° C
A polyester having an intrinsic viscosity of 0.8 to 2.0 as measured by; (In the formula, n represents an integer of 0 to 10.) (In the formula, R ¹ and R ² independently represent an alkylene group,
p is 3 or 4, q and r each independently represent 0 or an integer of 1 or more. ) [Chemical 6] (In the formula, R ³ represents an alkylene group, t is 2 or 3, and m represents an integer of 0 or 1 or more.) (B) An acid component containing terephthalic acid as a main component, ethylene glycol and butylene glycol A polyester copolymer comprising an aromatic polyester segment containing at least one of the above as a main component and an aliphatic segment obtained from at least one of a lactone monomer and a polylactone. 20 to 70% by weight of segment content
Is a polyester copolymer. 3. A polyester component containing 90 to 30 parts by weight of a polyester (A) shown below and 10 to 70 parts by weight of a polyester copolymer (C) shown below, and 100 parts by weight of the polyester component. On the other hand, an inner layer made of a polyester copolymer composition containing 0.3 to 5.0 parts by weight of polycarbodiimide, and a polyadipate,
At least one selected from the group consisting of polylactone, polycarbonate and polyol is used as the soft segment, and the number average molecular weight of the soft segment is 40.
A multi-layered tubular molded product having an outer layer consisting of a thermoplastic polyurethane elastomer having a soft segment content of 0 to 6000 and a soft segment content of 40 to 80% by weight: (A) represented by the following general formula [I]: And a dihydroxy compound represented by the following general formula [II] and / or at least one kind of a monohydroxy compound represented by the following general formula [III]. A polyester as a component, wherein the content of the hydroxy compound in which the dihydroxyl compound and the monohydroxy compound are combined is 2 to 1 with respect to all the monomers.
0 mol% and in o-chlorophenol at 30 ° C
A polyester having an intrinsic viscosity of 0.8 to 2.0 measured by (In the formula, n represents an integer of 0 to 10.) (In the formula, R ¹ and R ² independently represent an alkylene group,
p is 3 or 4, q and r each independently represent 0 or an integer of 1 or more. ) [Chemical 9] (In the formula, R ³ represents an alkylene group, t is 2 or 3, and m represents an integer of 0 or 1 or more.) (C) An acid component containing terephthalic acid as a main component, ethylene glycol and butylene glycol An aromatic polyester segment containing at least one of them as a main component and a diol component consisting of an acid component containing terephthalic acid as a main component and an aliphatic polyalkylene oxide having a number average molecular weight of 400 to 6000. A polyester copolymer comprising a polyester polyether segment as a constituent, wherein the content of the polyester polyether segment is 20 to 70% by weight.