JPH09272788A - Thermoplastic elastomer composition, its preparation, and hose using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic elastomer compsn. improved in softness and resistances to cold, heat, and oils by compounding a thermoplastic copolyester elastomer with a specific acrylic rubber. SOLUTION: 30-90wt.% thermoplastic copolyester elastomer, 10-70wt.% acrylic rubber having acrylic and epoxy groups as the rubber component, and if necessary a compd. having at least two carboxyl groups (of which a part may be a carboxylic anhydride group or groups) as the corosslinker are mixed and kneaded at 180-350 deg.C under a shear rate of 1,000-8,000sec<-1> for from 30sec to 10min to give a thermoplastic elastomer compsn. which satisfies the relations: 0.25<=ϕ1 <=0.90, 0.10<=ϕ2 <=0.75, ϕ1 +ϕ2 <=1.0, η2 /η1 <4.0, and (η1 /η2 )(ϕ2 /ϕ1 )<1.0 [η1 is the viscosity in melt kneading of the thermoplastic copolyester elastomer; ϕ1 is the vol. fraction of the elastomer; η2 is the viscosity in melt kneading of the acrylic rubber contg. no vulcanizing agent, i.e., in an unvulcanized state; and ϕ2 is the vol. fraction of the rubber].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer composition and a hose using the same, more specifically, it is composed of a thermoplastic copolyester elastomer and a specific acrylic rubber, and is used as an inner tube and / or an outer tube of the hose. A thermoplastic elastomer composition suitable for obtaining a hose which is excellent in oil resistance, flexibility, cold resistance, and heat resistance and can be produced without requiring a vulcanization step, and a hose using the same .

[0002]

2. Description of the Related Art A rubber hose usually consists of an inner pipe, a reinforcing layer and an outer pipe, and the inner pipe and the outer pipe are made of vulcanized rubber. Since such a rubber hose requires a vulcanization process, There is a problem that the manufacturing process becomes complicated. On the other hand, the inner tube and the outer tube are made of a thermoplastic resin,
A so-called resin hose is also known, which has a simple manufacturing process because it does not require a vulcanization process. However, the thermoplastic resin constituting this resin hose is generally harder than vulcanized rubber, and it is difficult to obtain a flexible hose, and the thermoplastic resin usually has a softening point of 120% by heat.
It was also difficult to use above ℃.

Further, in order to improve the flexibility of the thermoplastic resin, a resin hose having an inner tube made of a polyester thermoplastic elastomer having polybutylene terephthalate as a hard segment and polytetramethylene glycol or polycaprolactone as a soft segment. It is also known that this polyester-based thermoplastic elastomer has a limit in lowering the hardness in order to obtain the required heat-softening resistance and strength characteristics, and has sufficient flexibility and heat resistance like vulcanized rubber. Have not yet obtained a hose with.

Therefore, the development of a hose that can be manufactured by a simple process that does not require a vulcanization process and that has sufficient flexibility and heat resistance that can be used for pressure transmission at high temperature, fluid transportation, etc. has been developed. Was wanted. To meet such demand, a hose having an inner pipe and an outer pipe made of a thermoplastic elastomer in which a vulcanized rubber is dispersed in a thermoplastic resin has been proposed (see Japanese Patent Application No. 6-64102). .

This hose has an inner tube made of a thermoplastic elastomer in which a vulcanized composition of an acrylic group-containing rubber is dispersed in a thermoplastic polyester resin, and a thermoplastic resin in which a vulcanized rubber is dispersed in a thermoplastic resin. The outer tube is made of elastomer. Further, the reinforcing layer is formed by adhering an organic fiber such as rayon fiber, polyester fiber, or a hard rope or an inorganic rope to the inner tube and the outer tube via a room temperature curing type urethane adhesive or the like.

[0006]

Although a hose that is flexible at room temperature and does not require a vulcanization step can be obtained by the above-described structure, such a hose does not always have low-temperature characteristics, especially flexibility and cold resistance at low temperatures. It was not practically satisfactory, and it was necessary to further improve oil resistance.

Therefore, it is an object of the present invention to improve the flexibility (normal temperature and low temperature), oil resistance and cold resistance of a hose when it is used for an inner tube and / or an outer tube of a hose, and it is vulcanized. It is an object of the present invention to provide a thermoplastic elastomer composition which can be manufactured without requiring steps and can reduce the production cost, and a hose having the above-mentioned characteristics, which uses the same for an inner pipe and / or an outer pipe.

Another object of the present invention is to provide a thermoplastic elastomer composition having stable kneadability and high elongation at break, and a hose using the same.

[0009]

According to the present invention, (i)
30 to 90% by weight of at least one thermoplastic copolyester elastomer and (ii) 10 to 70% by weight of at least one acrylic rubber containing an acrylic group and an epoxy group as a rubber component (however, the sum of components (i) and (ii)) A thermoplastic elastomer composition containing 100% by weight) and a hose using the same for an inner tube and / or an outer tube are provided.

According to the invention, there is also provided a thermoplastic elastomer composition having a structure in which vulcanized rubber particles of acrylic rubber containing an acrylic group and an epoxy group are dispersed in at least one thermoplastic copolyester elastomer matrix. At a temperature of 180 to 350 ° C. and a shear rate of 1000 to 8000 s ⁻¹ , the viscosity η ₁ and the volume fraction φ _{1 of the} thermoplastic copolyester elastomer at the time of melt kneading and the unvulcanized state containing no vulcanizing agent. The viscosity η ₂ at the time of melt kneading of acrylic rubber and the volume fraction φ ₂ are
The following formula 0.25 ≦ φ ₁ ≦ 0.90 0.10 ≦ φ ₂ ≦ 0.75 φ ₁ + φ ₂ ≦ 1.0 η ₂ / η ₁ <4.0 (η ₁ / η ₂ ) (φ ₂ / Provided is a thermoplastic elastomer composition satisfying φ ₁ ) <1.0 and a hose using the same for an inner tube and / or an outer tube.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The thermoplastic elastomer composition constituting the inner tube and outer tube of the hose of the present invention means a thermoplastic copolyester elastomer in an amount sufficient to impart thermoplasticity and rubbery elasticity. A sufficient amount, at least in part, of a blend with a vulcanized acrylic rubber, in which the thermoplastic copolyester elastomer component has at least part of a continuous phase (matrix phase) in which a discontinuous phase (dispersed phase) Means that at least a part of vulcanized acrylic rubber is present in the rubber component. In addition, what is called a salami structure in which a thermoplastic resin is further dispersed in the discontinuous phase (rubber phase) may be used.

The thermoplastic copolyester elastomer which is the first component of the thermoplastic elastomer composition of the present invention is known as a multi-block copolymer having a polyester and a polyether as main repeating units. Such a known thermoplastic copolyester elastomer is used. Typical examples of the thermoplastic copolyester elastomer include the following.

The thermoplastic copolyester elastomer used in the present invention is a random or multiblock copolymer composed of repeating units of polyester and polyether, repeating units of polyester, (poly) lactone and polyether or repeating units of polyester and polyimide ether. Polyester, including copolyetherester elastomers, (poly) lactone modified copolyetherester elastomers and copolyetherimide ester elastomers.

Suitable thermoplastic copolyetherester elastomers and (poly) lactone-modified copolyetherester elastomers can be prepared by the conventional esterification / polycondensation method (i) at least one diol, (ii) at least 1 It is prepared from two dicarboxylic acids, (iii) at least one long-chain ether glycol and optionally (iv) at least one lactone or polylactone.

The diols (i) used in the preparation of the copolyetherester elastomers and their (poly) lactone-modified products include saturated and unsaturated aliphatic and cycloaliphatic dihydroxy compounds as well as aromatic dihydroxy compounds. These diols preferably have a low molecular weight, ie, a molecular weight of about 300 or less. Specific examples of the aliphatic and alicyclic diols include ethylene glycol, propanediol, butanediol, pentanediol, 2-methylpropanediol, 2,2-dimethylpropanediol, hexanediol, decanediol and 2-octylundecanediol. , 1,2-, 1,
3- and 1,4-dihydroxycyclohexane, 1,
Mention may be made of diols having 2 to 15 carbon atoms, such as 2-, 1,3- and 1,4-cyclohexanedimethanol, butynediol, hexenediol. Particularly preferred diols are 1,4-butanediol and mixtures of 1,4-butanediol with hexanediol or butynediol. Specific examples of the aromatic diol include resorcinol, hydroquinone, 1,5-
Examples include diols having 6 to 19 carbon atoms such as dihydroxynaphthalene, 4,4'-dihydroxydiphenyl, bis (p-hydroxyphenyl) methane and 2,2-bis (p-hydroxyphenyl) propane.

Particularly preferred diols are saturated aliphatic diols having from 2 to 8 carbon atoms and mixtures of such saturated aliphatic diols, as well as mixtures of such saturated aliphatic and unsaturated diols. . If two or more diols are used, it is preferred that the same diol accounts for at least about 60 mol%, especially at least 80 mol%, based on the total amount of diols. The most preferred diol mixture is one in which 1,4-butanediol is the majority.

Suitable dicarboxylic acids (ii) for use in preparing the copolyetherester elastomers and their (poly) lactone modified products include aliphatic, cycloaliphatic and / or aromatic dicarboxylic acids. These dicarboxylic acids are preferably of low molecular weight, ie having a molecular weight of about 350 or less, although higher molecular weight ones, especially dimer acids, can also be used.

Typical examples of the aliphatic and alicyclic dicarboxylic acids are sebacic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid and 1,4.
-Cyclohexanedicarboxylic acid, adipic acid, glutaric acid, succinic acid, oxalic acid, azelaic acid, diethylmalonic acid, allylmalonic acid, 4-cyclohexene-1,2-
Dicarboxylic acid, 2-ethylsperic acid, tetramethylsuccinic acid, cyclopentanedicarboxylic acid, decahydro-
1,5-naphthalenedicarboxylic acid, 4,4'-bicyclohexyldicarboxylic acid, decahydro-2,6-naphthalenedicarboxylic acid, 4,4-methylenebis (cyclohexanedicarboxylic acid), 3,4-furandicarboxylic acid, and 1, 1-cyclobutanedicarboxylic acid, as well as dimer acids thereof. Among these, cyclohexanedicarboxylic acid, sebacic acid, glutaric acid and adipic acid are preferable.

Representative examples of aromatic dicarboxylic acids are terephthalic acid, phthalic acid, isophthalic acid, bis-benzoic acid such as bis (p-carboxyphenyl) methane, oxybis (benzoic acid), ethylene-1,2-bis. (P-
Substituted dicarboxy compounds having two benzene nuclei such as (oxybenzoic acid), 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, phenanthenedicarboxylic acid, anthracenedicarboxylic acid, Included are 4,4'-sulfonyldibenzoic acids, and their halo and C1-C12 alkyl, alkoxy, and aryl-substituted derivatives. As long as the object of the invention is not attained, other aromatic dicarboxylic acids, such as p-
A hydroxy acid such as (β-hydroxyethoxy) benzoic acid can be used in combination.

Among the dicarboxylic acids used for the production of the copolyetherester elastomer and its (poly) lactone-modified products, among the aromatic dicarboxylic acids and mixtures of two or more aromatic dicarboxylic acids, as well as aromatic dicarboxylic acids and fats, Mixtures with group and / or cycloaliphatic dicarboxylic acids are preferred, with aromatic dicarboxylic acids alone being particularly preferred. Among the aromatic dicarboxylic acids, aromatic dicarboxylic acids having 8 to 16 carbon atoms, in particular, benzenedicarboxylic acids such as phthalic acid, terephthalic acid and isophthalic acid, and dimethyl esters thereof, are preferred. Dimethyl is best. When using a mixture of dicarboxylic acids or their esters,
It is preferred that at least about 60 mole%, especially at least about 80 mole%, based on the total amount of dicarboxylic acid, is the same dicarboxylic acid. Especially, it is best that dimethyl terephthalate accounts for about 60 mol% or more of the dicarboxylic acid mixture.

The long-chain ether glycol (iii) used for producing the thermoplastic copolyetherester elastomer and its (poly) lactone-modified product is preferably about 400.
Are poly (oxyalkylene) glycols and copoly (oxyalkylene) glycols having a molecular weight of about 12,000. Suitable poly (oxyalkylene) units are derived from long chain ether glycols having a molecular weight of about 900 to about 4,000 and having a carbon to oxygen ratio of about 1.8 to about 4.3 excluding side chains. To be done.

Representative examples of suitable poly (oxyalkylene) glycols are poly (ethylene ether) glycol, poly (propylene ether) glycol, poly (tetramethylene ether) glycol, ethylene oxide end-capped poly (propylene ether) glycol and a majority amount. Is a random or block copolymer of ethylene oxide and propylene oxide including copoly (propylene ether-ethylene ether) glycol having a poly (ethylene ether) skeleton, and tetrahydrofuran, and a small amount, for example, ethylene oxide, propylene oxide or methyltetrahydrofuran. Second
Or a block copolymer of the above (used at a ratio of carbon to oxygen not exceeding about 4.3). Formaldehyde and, for example, 1,4-
Polyformal glycols made by reacting diols such as butanediol and 1,5-pentanediol are also useful. Particularly preferred poly (oxyalkylene) glycols are poly (propylene ether) glycol, poly (tetramethylene ether) glycol and copoly (propylene ether-ethylene ether) glycol with a majority of polyethylene ether skeleton.

If desired, one or more lactones or polylactones (iv) can be added to these copolyetheresters. Polylactone modified copolyetherester elastomers of this type are disclosed in U.S. Pat. No. 4,569,973.

Suitable lactones (i) for use in the present invention
As v), ε-caprolactone is particularly preferred,
Substituted lactones substituted at the α, β, γ, δ or ε position with a lower alkyl group such as a methyl group or an ethyl group can also be used. Further, as a block unit of the copolyetherester used in the present invention, a homopolymer or a copolymer of the monomer and another copolymerizable monomer and a polylactone including a hydroxy-terminated polylactone can be used.

In general, suitable copolyetherester elastomers and their (poly) lactone modifications are the amount of (iii) the long chain ether glycol component or (iii) in the copolyetherester or (poly) lactone modifications. The total amount of the long chain ether glycol component and the (iv) lactone component is about 5 to about 80% by weight. A more preferred composition is one in which the amount of (iii) long chain ether glycol component or the total amount of said (iii) component and (iv) lactone component is from about 10 to about 50% by weight.

Among them, as a copolyether ester elastomer and its (poly) lactone modified product, a copolypolyester having a dicarboxylic acid component as terephthalic acid, a diol component as 1,4-butanediol and a long chain ether glycol as poly (tetramethylene ether) glycol. The ether ester elastomer is preferably exemplified.

The polyetherimide ester elastomers used in the present invention can be prepared from one or more diols, one or more dicarboxylic acids and one or more high molecular weight polyoxyalkylene diimide diacids. The preparation of such polyetherimide ester elastomers is described in U.S. Pat. No. 4,556,705.

The polyetherimide ester elastomers used in the present invention are prepared by conventional methods for preparing polyesters, such as those which produce random or block copolymers by esterification and condensation reactions. You can Thus, polyetherimide esters can generally be characterized as the reaction product of a diol and an acid.

Preferred polyetherimide ester elastomers used in the present invention are (i) one or more aliphatic or cycloaliphatic diols having 2 to 15 carbon atoms, (ii) one or more aliphatic or alicyclic diols. It can be prepared from a cyclic or aromatic dicarboxylic acid or ester derivative thereof, and (iii) one or more polyoxyalkylene diimidic diacids. The amount of polyoxyalkylenediimide diacid used will generally depend on the desired properties of the resulting polyetherimide ester. Generally, polyoxyalkylene diimidic diacid (iii)
The weight ratio of dicarboxylic acid (ii) is about 0.25 to about 2.0.
It is preferably in the range of about 0.4 to about 1.4.

The diols (i) used to prepare the above polyetherimide esters include saturated and unsaturated aliphatic and cycloaliphatic dihydroxy compounds as well as aromatic dihydroxy compounds. These diols have low molecular weight,
That is, those having a molecular weight of about 250 or less are preferred.

Particularly preferred diols are saturated aliphatic diols, mixtures thereof and mixtures of one or more saturated aliphatic diols with one or more unsaturated aliphatic diols, provided that each diol contains from 2 to 8 It has a carbon atom). When using more than one diol, at least about 60 based on total diol content.
It is preferred that mole%, more preferably at least 80 mole%, is the same diol. Particularly preferred diols are those having 1,4-butanediol as a main component, and the most preferred diol is 1,4-butanediol alone.

The dicarboxylic acid (ii) used in the production of the above polyetherimide ester is selected from aliphatic, alicyclic and aromatic dicarboxylic acids and their ester derivatives. Preferred dicarboxylic acids have a molecular weight of less than about 300 or have from 4 to 18 carbon atoms. However, higher molecular weight dicarboxylic acids,
In particular, dimer acids can also be used.

Among the aliphatic, alicyclic and aromatic dicarboxylic acids used for the production of the polyetherimide ester, the aromatic dicarboxylic acids and mixtures of two or more aromatic dicarboxylic acids, as well as the aromatic dicarboxylic acids and the aliphatic and / Or a mixture with an alicyclic dicarboxylic acid is preferred, and the aromatic dicarboxylic acid alone is particularly preferred. Among the aromatic dicarboxylic acids, aromatic dicarboxylic acids having 8 to 16 carbon atoms, in particular, benzenedicarboxylic acids such as phthalic acid, terephthalic acid and isophthalic acid, and dimethyl esters thereof, are preferred. Dimethyl is best.

The polyoxyalkylenediimidic diacid (iii) used to make the above polyetherimide ester is a high molecular weight diacid having an average molecular weight of greater than about 700, preferably greater than about 900. These diacids comprise two adjacent carboxyl groups or anhydride groups and further carboxyl groups (the other carboxyl group must be esterifiable and preferably not imidizable). ) Is produced by imidizing one or more tricarboxylic acid compounds containing a) with a high molecular weight polyoxyalkylenediamine.

The acrylic rubber used as the rubber component of the thermoplastic elastomer composition of the present invention is a crosslinkable rubber having an acrylic group and an epoxy group in the molecule as a main chain or a side chain, for example, an epoxy group-containing acrylate and Copolymer rubbers containing / or methacrylate as a copolymerization component can be mentioned. The epoxy group-containing (meth) acrylate copolymer or the epoxy group-containing (meth) acrylate copolymer rubber used in the present invention comprises (1) alkyl (meth) acrylate and / or alkoxy (meth) acrylate substitution. A multicomponent copolymer obtained by polymerizing an alkyl ester, (2) an epoxy group-containing monomer, and (3) another ethylenically unsaturated monomer copolymerizable with these (1) and (2), if necessary. It is a polymer rubber.

The (meth) acrylic acid alkyl ester (1) used for producing the epoxy group-containing (meth) acrylate copolymer rubber has the following formula:

[0037]

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(In the formula, R ₁ is an alkyl group having 1 to 18 carbon atoms, and R ₂ is hydrogen or a methyl group). Specific examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-. Pentyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-methylpentyl (meth) acrylate, n-octyl (meth) acrylate, 2-
Examples thereof include ethylhexyl (meth) acrylate, n-decyl (meth) acrylate, n-dodecyl (meth) acrylate, and n-octadecyl (meth) acrylate. Among them, ethyl (meth) acrylate, n-propyl (meth) acrylate, N-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and n-octyl (meth) acrylate are preferable.

Further, (meth) acrylic acid alkoxy-substituted alkyl ester (1.

[0040]

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(In the formula, R ₃ is hydrogen or a methyl group, and R _{4 is}
Is an alkylene group having 1 to 18 carbon atoms, and R ₅ is an alkylene group having 1 to 1 carbon atoms.
8 represents an alkyl group of 8). Specific examples of the (meth) acrylic acid alkyl ester include 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (n-propoxy) ethyl (meth) acrylate, and 2- (n-. Butoxy) ethyl (meth) acrylate, 3-methoxypropyl (meth)
Acrylate, 3-ethoxypropyl (meth) acrylate, 2- (n-propoxy) propyl (meth) acrylate, 2- (n-butoxy) propyl (meth) acrylate and the like can be mentioned.

Examples of the epoxy group-containing monomer used for producing the epoxy group-containing (meth) acrylate copolymer rubber include allyl glycidyl ether, glycidyl methacrylate, glycidyl acrylate, and the compounds shown below (each of the following formulas). In the formula, R ₆ represents hydrogen or a methyl group).

[0043]

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[0044]

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[0045]

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[0046]

[Chemical 6]

[0047]

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[0048]

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[0049]

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[0050]

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[0051]

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[0052]

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As a monomer to be copolymerized with the (meth) acrylic acid alkyl ester or the (meth) acrylic acid alkoxy-substituted alkyl ester (1) and the epoxy group-containing monomer, 2-cyanoethyl (meth ) Acrylate, 3-cyanopropyl (meth) acrylate, cyano-substituted alkyl (meth) acrylate such as 4-cyanobutyl (meth) acrylate, amino-substituted alkyl (meth) acrylate such as diethylaminoethyl (meth) acrylate, 1,1,1, Fluorine-containing (meth) acrylates such as 1-trifluoroethyl (meth) acrylate, hydroxyl group-substituted alkyl (meth) acrylates such as hydroxyethyl (meth) acrylate, alkyl vinyl ketones such as methyl vinyl ketone, vinyl ethyl ether , Vinyl or allyl ether such as allyl methyl ether, styrene, α-methyl styrene, chlorostyrene, vinyl aromatic compounds such as vinyl toluene, acrylonitrile, vinyl nitrile such as methacrylonitrile, acrylamide, methacrylamide, N-methylol acrylamide and the like Vinyl amide and ethylene, propylene, vinyl acetate and the like. The acrylic rubber used in the present invention is preferably an acrylic rubber comprising acrylic acid and an alkyl component having an alkyl component of C _{3 to} C _18. For example, 25% by weight of butyl acrylate, propyl acrylate, dodecyl acrylate, and hexadecyl acrylate may be used. The content is more preferably 30 to 60% by weight.

From the viewpoint of heat resistance, as a concrete component constitution of a rubber (acrylic rubber) containing an acrylic group and an epoxy group, an alkyl (meth) acrylate or an alkoxyalkyl (meth) acrylate (1) is used.
A copolymer rubber composed of ethyl acrylate alone and composed of glycidyl methacrylate as an epoxy group-containing monomer is, from the viewpoint of cold resistance, an alkyl (meth) acrylate or an alkoxy alkyl (meth) acrylate (1). A copolymer rubber composed of ethyl acrylate, butyl acrylate and methoxyethyl acrylate, and a glycidyl methacrylate as an epoxy group-containing monomer is preferably exemplified. Furthermore, in terms of the balance between heat resistance and cold resistance, it is preferable to select the type and amount of alkyl (meth) acrylate or alkoxy alkyl (meth) acrylate (1). Further, the epoxy group-containing monomer component, in the crosslinking of the copolymer rubber,
An epoxy group is used for a crosslinking reaction, and is usually 1 to 20.
What contains 1.5% by weight, preferably 1.5% by weight to 15% by weight, more preferably 2% by weight to 10% by weight is suitably used in the vulcanization reactivity dynamically performed during kneading described later.

The thermoplastic elastomer composition of the present invention comprises
Component (i): component (ii) = 30 to 90% by weight: 70 to 10% by weight (total 1
00% by weight), preferably component (i): component (ii) = 3
0 to 80% by weight: 70 to 20% by weight. If the compounding amount of the component (i) is too large, the flexibility is impaired, which is not preferable. On the contrary, if the compounding amount is too small, the mechanical strength is lowered and the rubber phase becomes a matrix phase, which impairs fluidity during extrusion processing. It is not preferable.

The thermoplastic elastomer composition according to the present invention contains, as a third component, a crosslinking agent compound having two or more carboxyl groups and / or carboxylic acid anhydride groups as carboxyl groups in the molecule. Is preferred. Typical examples of the crosslinking agent compound include the following compounds.

The crosslinking agent of the present invention is not particularly limited as long as it is a compound having two or more carboxyl groups and / or one or more carboxylic acid anhydride groups in the molecule. Preferably, aliphatic, cycloaliphatic and aromatic polycarboxylic acids, their (part) carboxylic anhydrides, and the (part) of these compounds with (poly) alkylene glycols
Esterified products are used. The molecular weight of the cross-linking agent is 5,
Those of 000 or less are preferable.

Specific examples of the aliphatic polycarboxylic acid include:
Examples include succinic acid, glutaric acid, pimelic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, dodecenylsuccinic acid, and butanetetracarboxylic acid. Specific examples of the alicyclic polycarboxylic acid include cyclopentane dicarboxylic acid, cyclopentane tricarboxylic acid, cyclopentane tetracarboxylic acid, cyclohexane dicarboxylic acid, cyclohexane tricarboxylic acid, methyl cyclohexane dicarboxylic acid, tetrahydrophthalic acid, endomethylene tetrahydrophthalic acid And methylendomethylenetetrahydrophthalic acid.
Specific examples of the aromatic polycarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid, and pyromellitic acid. Specific examples of the (partial) carboxylic acid anhydride include (partial) carboxylic acid anhydrides of these polycarboxylic acids.

The crosslinking agent compound is preferably added in an amount of 0.5 to 20 parts by weight, more preferably 1 to 15 parts by weight, per 100 parts by weight of the acrylic rubber component. Addition of such a crosslinking agent compound is preferable because the acrylic rubber dispersed phase is crosslinked, the mechanical strength is improved, and the setting resistance is improved.

The components of the thermoplastic elastomer composition used in the present invention are the thermoplastic copolyester elastomer and the acrylic rubber as described above, and such a thermoplastic copolyester elastomer composition contains at least one of the rubber components constituting the thermoplastic copolyester elastomer composition. The parts are crosslinked.
Such a thermoplastic copolyester elastomer composition,
Usually, using a Banbury mixer, Brabender mixer or other kneading extruder (two-screw kneading extruder), etc.
For example, a melt of the thermoplastic copolyester elastomer and the acrylic rubber is maintained in these devices to finely knead and disperse the rubber phase, and further to add a vulcanizing agent (crosslinking agent).
And kneading at a temperature that promotes crosslinking until the rubber phase is completely crosslinked.

That is, the thermoplastic elastomer composition produced in this manner progresses the vulcanization of the rubber while masticating the thermoplastic resin and the rubber composition, so to speak, dynamically proceeds the vulcanization. Dynamic Cure or Dy
(Namic Vulcanization). By using such a production method, the resulting thermoplastic elastomer composition has a vulcanized rubber phase in which at least a part becomes a discontinuous phase finely dispersed in a thermoplastic resin phase in which at least a part becomes a continuous phase. The thermoplastic elastomer composition exhibits the same behavior as the vulcanized rubber, and at least the continuous phase is the thermoplastic resin phase. Is possible.

Such a thermoplastic elastomer composition comprises at least a part of the thermoplastic resin as a continuous phase and at least a part of the rubber composition as a discontinuous phase, and the vulcanized rubber composition is a discontinuous phase. The particle size is preferably 50 μm or less, and more preferably 10 to 1 μm.

The kneading conditions, the type of vulcanizing agent used,
The amount, vulcanization conditions (temperature, etc.), etc. may be appropriately determined according to the compounding amount of the rubber composition to be added and the compounding amount of the rubber composition,
There is no particular limitation.

A method for producing such a thermoplastic elastomer composition of the present invention will be described below. In the production of the thermoplastic elastomer composition of the present invention, first, a resin and a rubber composition are added, melt-kneaded, and then a vulcanizing agent is added under kneading,
This can be done by dynamically vulcanizing the rubber.

Further, if necessary, a compounding agent such as a reinforcing agent, a softening agent and an antiaging agent may be added to the composition of the present invention. The compounding agent for the rubber component may be added during the kneading, but the compounding agent other than the vulcanizing agent is preferably mixed in advance before the kneading. The compounding agent for the resin component may be mixed in advance before the kneading, or may be added during the kneading.

The kneading machine used for producing the thermoplastic elastomer composition of the present invention is not particularly limited, and examples thereof include a screw extruder, a kneader, a Banbury mixer, and a twin-screw kneading extruder. Above all, it is preferable to use a twin-screw kneading extruder in consideration of the kneading of the resin component and the rubber component and the dynamic vulcanization of the rubber component. Further, two or more kinds of kneaders may be used and kneading may be sequentially performed.

As the conditions for melt-kneading, the kneading temperature is, for example, preferably 180 to 350 ° C., and particularly preferably 180 to 300 ° C., but is not particularly limited as long as it is at least the temperature at which the thermoplastic copolyester elastomer component is melted. Not done.
The shear rate at the time of kneading is 1000 to 8000 sec ^-1 , especially
It is preferably 1000 to 5000 sec ^-1 . The residence time of the entire melt-kneading is preferably 30 seconds to 10 minutes, and the residence time (vulcanization time) after adding the vulcanizing agent is preferably 15 seconds to 5 minutes. The shear rate is calculated by dividing the product obtained by multiplying the circumference of the circle drawn by the screw tip by the number of revolutions of the screw for one second by the gap at the tip. That is, the shear rate is
It is the value obtained by dividing the speed of the tip by the gap between the tips.

Here, the residence time in the portion where dynamic vulcanization is carried out is the total volume of the portion where dynamic vulcanization is carried out, multiplied by the filling factor,
It is calculated by dividing it by the volumetric flow rate.

When the thermoplastic elastomer composition is produced by such a production method, the relationship between the viscosity and the volume fraction of the thermoplastic elastomer used and the acrylic rubber composition at the time of melt-kneading are related to each other. Kneading temperature 180 ℃
It is preferable to make the relationship of the following formula within the range of -350 ° C and the shear rate of 1000-8000 s ^-1 . 0.25 ≦ φ ₁ ≦ 0.90, preferably 0.30 ≦ φ ₁
≦ 0.80 0.10 ≦ φ ₂ ≦ 0.75, preferably 0.20 ≦ φ ₂
≦ 0.70 φ ₁ + φ ₂ ≦ 1.0, preferably = 1.0 η ₂ / η ₁ <4.0, preferably <3.7 (η ₁ / η ₂ ) (φ ₂ / φ ₁ ) < 1.0 where η _{1 is} the viscosity of the thermoplastic copolyester elastomer during melt-kneading η _{2 is} the viscosity of the acrylic rubber composition during melt-kneading φ ₁ : Volume fraction of the thermoplastic copolyester elastomer φ ₂ : Acrylic rubber Volume fraction of the composition By kneading within the range of the above formula, the kneading property is stabilized, the rubber ratio is widely controlled, preferably a high rubber ratio can be realized, and it is flexible and has a high elongation at break. A thermoplastic elastomer composition can be obtained.

To produce the hose according to the present invention, the above-mentioned thermoplastic elastomer is used by known extrusion molding to produce the inner tube of the hose of the present invention, and the outer surface thereof is coated with an adhesive, if necessary. , After extruding the adhesive thermoplastic resin, wrap the reinforcing fiber or reinforcing steel wire on it in a blade or spiral shape, and further apply an adhesive if necessary, or extruding the adhesive thermoplastic resin, and then again the thermoplastic elastomer A general method of coating the outer tube by extrusion molding can be used, in which case the vulcanized product of acrylic rubber is dispersed in at least one of the inner tube and / or the outer tube in the thermoplastic copolyester elastomer described above. The thermoplastic elastomer composition is used.

In producing the hose according to the present invention, when a suitable adhesive is used as an adhesive layer between the inner pipe and the reinforcing layer made of fiber or steel wire and between the reinforcing layer and the outer pipe, As the adhesive, a urethane-based adhesive that has been generally used for hoses can be used. When an adhesive thermoplastic resin is used, a polyester copolymer resin or the like can be used. In each case, the thickness of the adhesive layer is not particularly limited, but is preferably 10 to 500 μm, respectively.

Next, as the reinforcing layer of the hose according to the present invention, organic fibers such as nylon fiber, vinylon fiber, rayon fiber, polyester fiber, aramid fiber, etc., which have been conventionally used for hoses, and nylon fibers, or hard Although it is possible to use a metal reinforcing layer such as steel wire, brass-plated steel wire, bronze-plated steel wire, and galvanized steel wire, polyester fiber is more preferably used in terms of economy, flexibility, strength, and modulus. To be

As described above, the hose according to the present invention is composed of the inner pipe, the reinforcing layer and the outer pipe in which the thermoplastic elastomer composition of the present invention is used for at least one of the inner pipe and the outer pipe. Accordingly, an adhesive layer may be included between the reinforcing layers.

[0074]

EXAMPLES The present invention will be further described with reference to the following examples, but it goes without saying that the scope of the present invention is not limited to these examples.

Examples 1 to 4 and Comparative Examples 1 to 4 A hose having an inner diameter of 6 mm and an outer diameter of 9.5 mm composed of an inner pipe, a reinforcing layer and an outer pipe having the constitution (material and wall thickness) as shown in Table I is manufactured. did. As the adhesive, Tylite 7411 moisture-curing urethane-based adhesive manufactured by Lord Far East Co. was used (each adhesive layer thickness 25 μm). The composition of each composition used for the inner tube and the outer tube in Table I is as shown in Table II.

[0076]

[Table 1]

[0077]

[Table 2]

The formulations of the NBR rubber composition and the CR rubber composition in Table II are as shown in Tables III and IV, respectively, and the monomer composition of the ACM (acrylic rubber) used is as shown in Table V. .

[0079]

[Table 3]

[0080]

[Table 4]

[0081]

[Table 5]

After these hoses were manufactured, they were allowed to stand at room temperature for 1 week, and then subjected to an impact pressure test on the flexural rigidity at 20 ° C. and −20 ° C. and the heat aged at 100 ° C. for 48 hours.

1) Bending Rigidity Test: <Hose Bending Rigidity> A sample hose is bent along an arc of various radii and the bending force [kg] is measured. Specifically, the measurement is started from a bending radius of 10 times the outer diameter of the sample hose, and the bending radius is sequentially changed up to 3 times to measure the bending force. A graph showing the relationship between the bending force and the bending radius is created from this measurement result, and the bending force at the specified radius (4 times) is read from the obtained graph to obtain the bending rigidity of the hose. With respect to the flexural rigidity of 2 kg (comparative example 1) of a normal rubber hose, the one that can be said to be equivalent to the flexibility in use in the range of ± 20% was marked with ◯, and the one that was stiffened by + 20% or more was marked with x.

2) Impact pressure test: Conforms to JIS K6379 As the test oil, mineral oil corresponding to two kinds specified in JIS K2213 (turbine oil) is used, and a rectangular wave having a maximum pressure of 27.5 MPa at an oil temperature of 93 ° C. is used. It was repeatedly added 10,000 times and the presence or absence of breakage was confirmed (○… no breakage).

Comparative Example 1 requires a vulcanization step because it is a vulcanized rubber rather than the thermoplastic elastomer of the present invention, but Examples 1 to 4 of the present invention are the same as Comparative Example 1 which is a conventional example. On the other hand, since the vulcanization process is not required, the manufacturing cost can be significantly reduced. Further, Comparative Examples 2 to 4 which are outside the scope of the present invention
However, there is an advantage that the bending rigidity at low temperature is low. Since Comparative Examples 2 to 4 use the thermoplastic elastomer according to the present invention, there is an advantage that the vulcanization step is unnecessary and the manufacturing cost can be significantly reduced, but the acrylic rubber used does not satisfy the preferable conditions. , You do not get the benefit of flexibility at low temperatures. Therefore, it can be seen that the hose using the composition of the present invention does not require a vulcanization step and thus can reduce the manufacturing cost and is excellent in flexibility at low temperature.

Examples 5 to 8 Hoses each having an inner diameter of 9.5 mm and an outer diameter of 17.5 mm and having an inner tube, a reinforcing layer and an outer tube having the constitutions shown in Table VI were manufactured according to the prescription. The results are shown in Table VI.

[0087]

[Table 6]

The respective constituents shown in Table VI are as shown in Table VII, and the constituents used therein are as follows.
The composition 9 and the composition 11 both had a temperature of 250 ° C.,
The one kneaded at a shear rate of 2432 s ⁻¹ was used. That is, the compositions used in Examples 5 to 8 are all thermoplastic elastomer compositions within the scope of the present invention.
In each of Examples 5 to 8, the bending rigidity at low temperature is low, and the result of the impact pressure test is also good.

Adhesive (No. 1) = Moisture-curable urethane adhesive: Tylite 7411 (manufactured by Road Far East) Adhesive (No. 2) = Thermoplastic resin adhesive: Hytrel 2531 (Toray DuPont) Adhesive (No.3) = Thermoplastic resin adhesive: Admer Q
B-540 (Mitsui Petrochemical)

After these hoses were manufactured, they were allowed to stand at room temperature for 1 week, and then the flexural rigidity at 20 ° C. and −20 ° C. was determined. The results are shown in Table VI.

In each of Examples 5 to 8, since the thermoplastic elastomer composition of the present invention was used for the inner tube and / or the outer tube, the vulcanization step was unnecessary, and the flexibility at low temperature was improved. Are better.

Examples 9-23 Table VII shows examples of thermoplastic elastomer compositions other than the compositions used in Examples 5-8. From these comparisons, the superiority of the elongation at break of the thermoplastic elastomer composition satisfying the relationship between the viscosity and the volume fraction during melt-kneading of the thermoplastic elastomer used in the present invention and the acrylic rubber composition is clear.

[0093]

[Table 7]

[0094]

[Table 8]

[0095]

[Table 9]

[0096]

[Table 10]

COPE: Thermoplastic Copolyester Elastomer Lomod ER3055A (manufactured by GE Plastics) Hytrel5556 (manufactured by Toray-Dupont) Hytrel5557 (manufactured by Toray-Dupont) Hytrel5577 (manufactured by Toray-Dupont) FEF carbon black ( N550) = Seast S0
(Tokai Carbon Co., Ltd.) Anti-aging agent = Irganox 1010: Hindered phenol anti-aging agent made by Nippon Ciba Geigy Pentaerythrityl-tetrakis [3- (3,5-di-
Tertiary butyl-4-hydroxyphenyl) propionate] Crosslinking agent BTC = butane tetracarboxylic acid manufactured by Mitsui Toatsu Fine Co., Ltd.

[0098]

As described below, according to the present invention,
By using a composition consisting of a thermoplastic copolyester elastomer and acrylic rubber as the inner tube and / or outer tube of a hose, it is excellent in oil resistance, flexibility and cold resistance, and requires a processing (vulcanization) step. You can get a hose that doesn't.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location C08L 33/14 C08L 33/14 33/26 LJV 33/26 LJV 63/00 NJX 63/00 NJX ( 72) Inventor Takashi Sato No.2-1 Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Co., Ltd. Hiratsuka Factory

Claims (7)

[Claims] 1. At least one thermoplastic copolyester elastomer (i) 30 to 90% by weight and (ii) at least one acrylic rubber containing an acrylic group and an epoxy group as a rubber component 10 to 70% by weight (provided that the component ( A thermoplastic elastomer composition comprising i) and (ii) in a total amount of 100% by weight). 2. The acrylic acid and the alkyl component are C _{3 to} C ₁₈
25% by weight of acrylic rubber consisting of alkyl ester
The thermoplastic elastomer composition according to claim 1, containing the above. 3. The thermoplastic elastomer composition according to claim 1, further comprising, as a cross-linking agent, a compound having at least one of a carboxyl group and a carboxylic acid anhydride group as a carboxyl group. 4. The thermoplastic elastomer composition according to claim 1, wherein the rubber component is crosslinked and dispersed as a dispersed phase in the matrix phase of the thermoplastic copolyester elastomer. 5. A thermoplastic elastomer composition having a structure in which vulcanized rubber particles of an acrylic rubber having an acrylic group are dispersed in at least one thermoplastic copolyester elastomer matrix, and a temperature of 180 to 35.
At 0 ° C. and a shear rate of 1000 to 8000 s ⁻¹ , the viscosity η ₁ and the volume fraction φ _{1 of the} thermoplastic copolyester elastomer during melt kneading, and the melting of the unvulcanized acrylic rubber containing no vulcanizing agent The viscosity η ₂ at the time of kneading and the volume fraction φ ₂ are expressed by the following formulas: 0.25 ≦ φ ₁ ≦ 0.90 0.10 ≦ φ ₂ ≦ 0.75 φ ₁ + φ ₂ ≦ 1.0 η ₂ / η _A thermoplastic elastomer composition satisfying ₁ <4.0 (η ₁ / η ₂ ) (φ ₂ / φ ₁ ) <1.0. 6. A thermoplastic copolyester elastomer
Vulcanized rubber particles of acrylic rubber are dispersed in the tricks.
A thermoplastic elastomer composition having a different structure
Above the melting temperature of the copolyester elastomer
Containing a thermoplastic copolyester elastomer and a vulcanizing agent.
Do not knead and disperse the unvulcanized acrylic rubber, then
Dynamic heat treatment in the presence of a vulcanizing agent continuously with kneading
To produce a thermoplastic elastomer having the above structure
In the method, a thermoplastic copolyester elastomer
Viscosity of melt kneading₁And volume fraction φ₁And vulcanizing agent
During melt kneading of unvulcanized acrylic rubber without compounding
Viscosity η_TwoAnd volume fraction φ _TwoIs heat that satisfies the following formula
Plastic copolyester elastomer and acrylic rubber down
Notation: 0.25 ≦ φ₁≦ 0.90 0.10 ≦ φ_Two≤ 0.75 φ₁+ Φ_Two≦ 1.0 η_Two/ Η₁<4.0 (η₁/ Η_Two) (Φ_Two/ Φ₁) Kneading and heat treatment at a temperature and shear rate satisfying <1.0
Method for producing plastic elastomer composition. 7. An inner tube and / or an outer tube of a hose comprising at least an inner tube, a reinforcing layer and an outer tube.
7. A hose composed of the thermoplastic elastomer composition according to any one of 6 above.