JP2017177548A - Laminated structure and hollow structure comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated structure having low fuel permeability, excellent flexibility and workability, and excellent mechanical strength and impact resistance.SOLUTION: Provided is a laminated structure for a hollow structure, comprising: as an outer layer, an olefinic thermoplastic elastomer layer (A) containing an olefinic thermoplastic elastomer; as a middle layer, an adhesive layer (B) containing a modified propylene-based polymer; and, as an inner layer, a semi-aromatic polyamide layer (C) containing a semi-aromatic polyamide. Here, the modified propylene-based polymer is chosen to be a polymer obtained by grafting an unsaturated carboxylic acid or a derivative thereof to a propylene-based polymer. The adhesive layer (B) has a density set at 0.880 to 0.920 g/cmas measured in accordance with ASTM D1505. Further, the olefinic thermoplastic elastomer layer (A) has a melt elongation set at 1 to 100 m/min as measured by a capillary rheometer under a specific condition.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminated structure and a hollow structure including the same.

  Resin tubes, unlike metal tubes, do not rust, are easy to process and lightweight, and have many advantages such as a high degree of freedom in design, so their application range is expanding. In the production of a conventional resin tube, a thermoplastic resin mainly composed of polyamide (PA) is used.

  Polyamide 12 (PA12) and polyamide 11 (PA11), which are excellent in flexibility, are currently used in many fuel pipes for automobiles. In recent years, from the viewpoint of environmental pollution prevention and the like, regulations for transpiration of fuel gas for automobiles and the like have become strict. Therefore, the fuel pipe is required to have low fuel gas permeability. Furthermore, alcohol gasoline blended with low-boiling alcohols such as methanol and ethanol has been put into practical use from the viewpoint of saving gasoline consumption and improving performance, and conventional fuel (gasoline etc.) can be used only for fuel pipe hoses. There is also a demand for low permeability of alcohol gasoline and the like. Accordingly, a fuel pipe has been developed in which a barrier layer (inner layer) containing a fluororesin or a semi-aromatic polyamide is formed inside a conventional tube made of polyamide 12 or polyamide 11 (Patent Document 1). Furthermore, a fuel pipe having an outer layer made of polyethylene, an intermediate layer made of an adhesive layer, and an inner layer containing a semi-aromatic polyamide has also been proposed (Patent Document 2).

  In recent years, with the downsizing of the engine and the downsizing of the engine room, the piping for the coolant and fuel arranged around the engine is required to be freely handled. Furthermore, since piping often comes into contact with other members and rubs or is exposed to vibration from other members, the piping is also required to have mechanical strength and impact resistance. Conventionally, piping has been protected by inserting the piping into a protection tube made of vulcanized rubber. However, the rubber protective tube has poor lubricity with the piping and is difficult to attach. Therefore, it has been necessary to make the protect tube a structure that can secure an air layer between the pipes and to apply a lubricant made of silicon or the like to the pipe surface. However, such a response requires a complicated manufacturing process and tends to increase costs.

  Therefore, it has been proposed to form a protective layer made of a foamable thermoplastic elastomer or a flame retardant thermoplastic elastomer on the pipe surface made of polyamide resin or the like (Patent Document 3).

Special table 2007-502726 Japanese Patent Laying-Open No. 2015-231709 JP 2005-265102 A

  As in the above-mentioned Patent Document 1 and Patent Document 2, in a pipe made of a laminated structure using polyamide 11, polyamide 12, polyethylene, etc. for the outer layer, the outer layer has low flexibility and is difficult to process into a desired shape. There was a problem. Furthermore, the polyamide 11 and the polyamide 12 are relatively expensive, and there is a problem that it is difficult to reduce the cost of the laminated structure.

  On the other hand, as in Patent Document 3, when the foamable thermoplastic elastomer is used as the outer layer, there is a problem that a step of foaming the resin is necessary, and it is difficult to increase productivity.

  The present invention has been made in view of the above circumstances. That is, the present invention provides a laminated structure having low fuel permeability and excellent flexibility and workability.

That is, the first of the present invention relates to the following laminated structure.
[1] An olefinic thermoplastic elastomer layer (A) containing an olefinic thermoplastic elastomer as an outer layer, an adhesive layer (B) containing a modified propylene polymer as an intermediate layer, and a semi-aromatic containing a semiaromatic polyamide as an inner layer A laminated structure for a hollow structure having an aromatic polyamide layer (C), wherein the modified propylene polymer contained in the adhesive layer (B) is a propylene homopolymer and / or propylene / α-olefin A copolymer obtained by graft-modifying an unsaturated carboxylic acid or a derivative thereof on a copolymer, and the adhesive layer (B) has a density measured in accordance with ASTM D1505 of 0.880 to 0.920 g / cm ^3. The olefinic thermoplastic elastomer layer (A) has a melt elongation of 1 to 100 m / min measured by a capillary rheometer under the following conditions. That, the laminated structure.
(Measurement conditions in capillary rheometer)
Strand length: 10mm
Orifice hole diameter: 1 mm
Melting temperature: 290 ° C
Crosshead speed: 50mm / min

[2] The laminate structure according to [1], wherein the modified propylene polymer included in the adhesive layer (B) includes 0.08 to 5% by mass of the structure derived from the unsaturated carboxylic acid or a derivative thereof. .
[3] The laminated structure according to [1] or [2], wherein the modified propylene-based polymer included in the adhesive layer (B) includes a structure derived from maleic anhydride.
[4] The laminated structure according to any one of [1] to [3], further including a conductive layer containing a resin and a conductive filler in the innermost layer.
[5] The semi-aromatic polyamide layer (C) includes a semi-aromatic polyamide resin and a modified olefin polymer obtained by modifying an olefin polymer with a compound containing a hetero atom, and the semi-aromatic polyamide The resin has a structural unit derived from terephthalic acid [a] and a structural unit derived from an aliphatic diamine [d] having 4 to 12 carbon atoms, and the amount of the structural unit derived from terephthalic acid [a] is 40 to 100 mol% with respect to all dicarboxylic acid structural units, and the amount of the structural unit derived from the aliphatic diamine [d] is 60 to 100 mol% with respect to all diamine structural units, [1] to [4] The laminated structure according to any one of [4].
[6] The modified ethylene / α-olefin copolymer obtained by graft-modifying an ethylene / α-olefin copolymer with an unsaturated carboxylic acid or a derivative thereof is used as the modified olefin polymer contained in the semi-aromatic polyamide layer (C). The laminated structure according to [5], which is a coalescence.

[7] The semi-aromatic polyamide layer (C) includes a semi-aromatic polyamide resin and a modified olefin polymer obtained by modifying an olefin polymer with a compound containing a hetero atom, and the semi-aromatic polyamide The resin is a structural unit derived from terephthalic acid [a], a structural unit derived from isophthalic acid [b], a structural unit derived from an aliphatic dicarboxylic acid [c] having 4 to 10 carbon atoms, and a number of carbon atoms from 4 to 12 structural units derived from an aliphatic diamine, 35-50 mol% of structural units derived from the terephthalic acid [a], 25-40 mol% of structural units derived from the isophthalic acid [b], and the fat. 15 to 35 mol% of structural units derived from the group dicarboxylic acid [c] (provided that the total of [a], [b] and [c] is 100 mol%), and the structure derived from the terephthalic acid [a] Units and said isophthalic acid [b] The molar ratio ([a] / [b]) to the structural unit is 65/35 to 50/50, the structural unit derived from the aliphatic dicarboxylic acid [c] and the isophthalic acid [b] The molar ratio ([c] / [b]) to the structural unit is 30/70 to 50/50, and the heat of fusion (ΔH) obtained by differential scanning calorimetry (DSC) of the semiaromatic polyamide resin is The laminated structure according to any one of [1] to [4], which is 20 to 40 mJ / mg, and the semi-aromatic polyamide resin has an intrinsic viscosity [η] of 0.7 to 1.6 dl / g. body.
[8] A modified ethylene / α-olefin copolymer obtained by graft-modifying an ethylene / α-olefin copolymer with an unsaturated carboxylic acid or a derivative thereof, wherein the modified olefin polymer contained in the semi-aromatic polyamide layer (C) The laminated structure according to [7], which is a coalescence.
[9] The olefinic thermoplastic elastomer included in the olefinic thermoplastic elastomer layer (A) includes a segment made of propylene resin and a segment made of olefinic copolymer rubber. ] The laminated structure in any one of.

2nd of this invention is related with the following hollow structures.
[10] A hollow structure comprising the laminated structure according to any one of [1] to [9].
[11] The hollow structure according to [10], which is selected from the group consisting of a hose and a tube.
[12] The hollow structure according to [10] or [11], which is a fuel piping tube.
[13] The hollow structure according to [10] or [11], which is a cooling system piping tube.

  The laminated structure of the present invention has low fuel permeability and excellent flexibility and workability.

It is a schematic sectional drawing which shows an example of the hollow structure which consists of a laminated structure of this invention. It is a side view which shows the structure of the measuring apparatus of the bending load just before bending in an Example.

1. Laminated structure The laminated structure of the present invention is for a hollow structure having an olefinic thermoplastic elastomer layer (A) as an outer layer, an adhesive layer (B) as an intermediate layer, and a semi-aromatic polyamide layer (C) as an inner layer. It is a structure. Here, the hollow structure means a structure having a space inside, and examples of the hollow structure include tubes, bottles, tanks, and the like. In the present invention, the laminated structure itself may be formed to have a hollow structure such as a tube shape. Moreover, the laminated structure is formed in a film shape or a flat plate shape, and may be processed so as to have a hollow structure by molding.

  Here, the laminated structure of the present invention is suitable for hoses and tubes for transporting gas and liquid, bottles and tanks for storing gas and liquid therein, and the like. In particular, the laminated structure of the present invention has low fuel permeability for automobiles and is excellent in flexibility and workability. Therefore, it is preferably used for various hollow structures (molded products) for fuel storage or fuel transportation. Here, the fuel refers to various fuels such as gasoline, alcohol-mixed gasoline (gasohol), alcohol, hydrogen, light oil, biodiesel fuel, dimethyl ether, LPG, CNG and the like. The laminated structure of the present invention is also preferably used for various hollow structures (molded products) for cooling pipes for conveying a cooling liquid.

  FIG. 1 is a schematic sectional view showing an example of a hollow structure (fuel piping tube) made of the laminated structure of the present invention. In the laminated structure 100 of the present invention, the olefinic thermoplastic elastomer layer (A) is the outer layer 1, the adhesive layer (B) is the intermediate layer 2, and the semi-aromatic polyamide layer (C) is the inner layer 3. The outer layer 1 is a layer disposed on the outer surface side of various hollow structures, and is a layer for protecting the inner layer 3 of the laminated structure 100 from the external environment and maintaining strength. On the other hand, the inner layer 3 is a layer disposed on the inner side of various hollow structures, and is a layer for suppressing gas or liquid from leaking to the outside or evaporating from the inside of the various hollow structures. is there. The intermediate layer 2 is a layer for bonding them.

  As described above, the laminated structure using polyamide 11, polyamide 12, or polyethylene as the outer layer has a problem that it has low flexibility and is difficult to be processed into a desired shape. On the other hand, when a foamable thermoplastic elastomer or a flame retardant thermoplastic elastomer is used for the outer layer, there is a problem that the mechanical strength of the outer layer is low although the impact resistance is high.

  On the other hand, in this invention, the impact resistance and mechanical strength of a laminated structure can be made high by using an olefin type thermoplastic elastomer layer (A) as an outer layer. And the semi-aromatic polyamide layer (C) which is an inner layer can be protected from an external impact, a vibration, etc. Further, since the olefinic thermoplastic elastomer layer (A) has a specific melt elongation, there is also an advantage that the laminated structure can be easily processed into an arbitrary shape. On the other hand, since the laminated structure of the present invention contains a semi-aromatic polyamide (C), the fuel permeability is low. That is, the laminated structure of the present invention has low fuel permeability and can be processed into a desired shape. Therefore, it can be applied to various hollow structures (molded products) such as fuel storage tanks and bottles, fuel transfer tubes and hoses, and cooling system tubes and hoses. In addition, as will be described later, the laminated structure of the present invention has an advantage that it can be prepared without going through a complicated manufacturing process.

  Hereinafter, each layer of the laminated structure will be described.

1-1. Olefin-based thermoplastic elastomer layer (A)
The olefinic thermoplastic elastomer layer (A) is a layer containing at least an olefinic thermoplastic elastomer, and the melt elongation measured by a capillary rheometer of the olefinic thermoplastic elastomer layer (A) is 1 to 100 m / min. is there.

Here, the melt elongation of the olefinic thermoplastic elastomer layer (A) refers to the melt elongation (take-off speed at the time of yarn breakage) measured by using a capillary rheometer and changing the take-up speed under the following conditions. For example, a capillary rheometer 1C manufactured by Toyo Seiki Seisakusho can be used as the capillary rheometer. Moreover, a measurement can be measured based on JISK7199.
(Measurement conditions in capillary rheometer)
Strand length: 10mm
Orifice hole diameter: 1 mm
Melting temperature: 290 ° C
Crosshead speed: 50mm / min

  The melt elongation is more preferably 1 to 50 m / min, and further preferably 1 to 30 m / min. When the melt elongation is 1 m / min or more, the flexibility and workability of the laminated structure are likely to increase. On the other hand, when the melt elongation is 100 m / min or less, the mechanical strength of the laminated structure is likely to be sufficiently increased. The said melt elongation is adjusted with the kind of component which an olefin type thermoplastic elastomer layer contains.

  Here, the olefin-based thermoplastic elastomer layer (A) may be a layer made of only the olefin-based thermoplastic elastomer, and includes a softener, various rubbers, inorganic fillers, various additives, and the like as necessary. It may be a layer. However, it is preferable that 60 mass% of olefinic thermoplastic elastomer is included with respect to the total mass of an olefinic thermoplastic elastomer layer (A), and it is preferable to include 80 mass% or more. When the amount of the olefinic thermoplastic elastomer is 60% by mass or more, the heat resistance and flexibility of the olefinic thermoplastic elastomer layer (A) are likely to be increased, and interlayer adhesion with the adhesive layer (B) described later is increased. It becomes easy.

  The olefinic thermoplastic elastomer contained in the olefinic thermoplastic elastomer layer (A) can be an elastomer containing a segment made of polyolefin resin and a segment made of olefinic copolymer rubber. Preferable examples of the olefin thermoplastic elastomer include an elastomer obtained by dynamically heat-treating a polyolefin resin and an olefin copolymer rubber in the presence of a crosslinking agent. In this specification, “dynamically heat-treating” refers to kneading in a molten state.

  Examples of the olefinic thermoplastic elastomer contained in the olefinic thermoplastic elastomer layer (A) include an ethylene copolymer comprising a polypropylene resin (a1) and ethylene / α-olefin or ethylene / α-olefin / non-conjugated polyene. An elastomer obtained by dynamically heat-treating a mixture containing the combined rubber (a2) in the presence of a crosslinking agent is included. Moreover, the said mixture may further contain a polyethylene-type resin (a3). At this time, the amount of the polypropylene resin (a1) is preferably 10 to 60% by mass with respect to the total amount of the olefinic thermoplastic elastomer obtained, and the amount of the ethylene copolymer rubber (a2) is 37. It is preferable that it is -87weight%. Moreover, when an olefin type thermoplastic elastomer contains a polyethylene-type resin (a3), the quantity of a polyethylene-type resin (a3) shall be 3-30 mass% with respect to the total amount of the olefin type thermoplastic elastomer obtained. Is preferred. By setting it as such a composition, it becomes easy to satisfy | fill the said melt elongation, and it becomes easy to obtain the olefin type thermoplastic elastomer which has a softness | flexibility, workability, and mechanical strength.

  From the viewpoint of heat resistance, the polypropylene resin (a1) used for the preparation of the olefin thermoplastic elastomer is a propylene homopolymer, a block copolymer of propylene and an α-olefin, or an α-olefin of propylene. It is preferable that this is a random copolymer. In the mixture for preparing the olefinic thermoplastic elastomer described above, the polypropylene resin (a1) may contain only one kind or two or more kinds. When the polypropylene resin (a1) is a copolymer of propylene and an α-olefin, the amount of the structural unit derived from propylene is 80 with respect to the total molar amount of the structural units constituting the copolymer. It is preferably at least mol%, more preferably at least 85 mol%. When the amount of the structural unit derived from propylene is within the above range, the flexibility and molding processability of the resulting olefin-based thermoplastic elastomer are likely to increase.

  When the polypropylene resin (a1) is a propylene homopolymer or a propylene / α-olefin block copolymer, the structure of the polypropylene chain is not particularly limited, and may be an isotactic structure. It may be a tic structure or an atactic structure.

  When the polypropylene resin (a1) is a propylene / α-olefin random copolymer or a propylene / α-olefin block copolymer, the α-olefin constituting the polypropylene resin (a1) has 2 to 20 carbon atoms. (However, excluding polypropylene) is preferable, and 2 to 10 (however, excluding polypropylene) is more preferable. Specific examples of the α-olefin include ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 2-methyl-1-propene, 3-methyl-1-pentene and 4-methyl. -1-pentene, 5-methyl-1-hexene and the like are included.

  Moreover, it is preferable that the melt flow rate (230 degreeC, 2.16kg load) measured based on ASTM D1238 of the said polypropylene resin (a1) is 0.1-200 g / 10min, 0.5- 100 g / 10 min is more preferable, and 1 to 50 g / 10 min is more preferable. When the melt flow rate of the polypropylene resin (a1) is within the above range, the fluidity during molding of the resulting olefinic thermoplastic elastomer is increased, and the olefinic thermoplastic elastomer layer (A) having a uniform thickness is obtained. It becomes easy. The melt flow rate of the polypropylene resin (a1) is adjusted by the molecular weight or the like.

The density of the polypropylene resin (a1) is preferably 0.890~0.920g / cm ^3, more preferably 0.895~0.915g / cm ^3, 0.900~0 More preferably, it is 910 g / cm ³ . The density is a value measured according to ASTM D1505. When the density of the polypropylene-based resin (a1) is 0.920 g / cm ³ or less, the flexibility of the resulting olefin-based thermoplastic elastomer layer (A) is likely to increase, and as a result, the flexibility of the laminated structure is likely to increase. On the other hand, when the density is 0.890 g / cm ³ or more, the resulting olefinic thermoplastic elastomer layer (A) is less likely to swell even when exposed to vaporized fuel or the like, resulting in mechanical strength and impact resistance. Sex is less likely to change. The density of the polypropylene resin (a1) is adjusted by the type of the polypropylene resin (a1) (for example, a copolymer), the preparation conditions, and the like.

  On the other hand, the ethylene copolymer rubber (a2) used for the preparation of the olefinic thermoplastic elastomer may be an amorphous random elastic polymer of ethylene and α-olefin. Any amorphous random elastic polymer with a conjugated polyene may be used, but an amorphous random elastic polymer with ethylene, an α-olefin, and a nonconjugated polyene is more preferable. The mixture used for the preparation of the olefinic thermoplastic elastomer may contain only one type of ethylene copolymer rubber (a2), or may contain two or more types.

  The amount of ethylene-derived structural unit (ethylene content) in the ethylene-based copolymer rubber (a2) is from 50 to the molar amount of all the structural units constituting the ethylene-based copolymer rubber (a2). It is preferably 95 mol%, more preferably 50 to 90 mol%, and preferably 60 to 85 mol%. On the other hand, the amount of the structural unit derived from an α-olefin having 3 to 20 carbon atoms is preferably 5 to 50 mol%, more preferably 10 to 50 mol%, and 15 to 40 mol%. Is more preferable. The amount of the structural unit derived from non-conjugated polyene is preferably 0.1 to 5 mol%, more preferably 0.5 to 4 mol%, and further preferably 1 to 4 mol%. . By setting it as such a component ratio, the softness | flexibility and molding processability of an olefin type thermoplastic elastomer obtained by bridge | crosslinking the said mixture are easy to improve.

  In both cases where the ethylene copolymer rubber (a2) is an ethylene / α-olefin copolymer rubber and an ethylene / α-olefin / non-conjugated polyene copolymer rubber, ethylene and α The molar ratio with the olefin is preferably 95/5 to 50/50.

  Here, the number of carbon atoms of the α-olefin other than ethylene constituting the ethylene-based copolymer rubber (a2) is preferably 3-20, and more preferably 3-10. Specific examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 2-methyl-1-propene, 3-methyl-1-pentene and 4-methyl. -1-pentene, 5-methyl-1-hexene and the like are included.

  Specific examples of the non-conjugated polyene constituting the ethylene copolymer rubber (a2) include dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene, vinyl norbornene and the like.

  Specific examples of the ethylene copolymer rubber (a2) include ethylene / propylene copolymer rubber, ethylene / propylene / non-conjugated polyene copolymer rubber, ethylene / 1-butene copolymer rubber, ethylene / 1-butene. -Non-conjugated polyene copolymer rubber and the like are included. Among these, ethylene / propylene / non-conjugated polyene copolymer rubber is preferable, and ethylene / propylene / ethylidene norbornene copolymer rubber and ethylene / propylene / dicyclopentadiene copolymer rubber have an appropriate crosslinked structure. It is preferable from a viewpoint that the olefin type thermoplastic elastomer which has is obtained.

  The ethylene copolymer rubber (a2) preferably has a Mooney viscosity [ML1 + 4 (125 ° C.)] of 10 to 250, more preferably 30 to 150. When the Mooney viscosity is in the above range, the flexibility and processability of the resulting olefinic thermoplastic elastomer layer (A) are likely to increase.

  Further, the iodine value of the ethylene copolymer rubber (a2) is preferably 30 or less, and more preferably 25 or less. When the iodine value of the ethylene copolymer rubber (a2) is 30 or less, an olefinic thermoplastic elastomer having an appropriate cross-linked structure is obtained.

  The polyethylene resin (a3) used for the preparation of the olefinic thermoplastic elastomer may be an ethylene homopolymer, a random polymer of ethylene and α-olefin, or a block copolymer of ethylene and α-olefin. It may be a coalescence. The mixture used for the preparation of the olefinic thermoplastic elastomer may contain only one kind of polyethylene polymer (a3), or may contain two or more kinds. When the polyethylene resin (a3) is an ethylene / α-olefin copolymer, the amount of the structural unit derived from ethylene (ethylene content) is the molar amount of all the structural units constituting the polyethylene resin (a3). On the other hand, it is preferably 85 to 99.9 mol%, more preferably 90 to 99 mol%, and still more preferably 95 to 99 mol%.

  The α-olefin other than ethylene constituting the polyethylene resin (a3) preferably has 3 to 20 carbon atoms, and more preferably 4 to 8 carbon atoms. The said alpha olefin can be made into the same alpha olefin as what was illustrated as an alpha olefin used for ethylene-type copolymer rubber (a2).

  Moreover, it is preferable that the melt flow rate (190 degreeC, 2.16kg load) measured based on ASTM D1238 of a polyethylene-type resin (a3) is 0.1-50 g / 10min, and is 1-30 g / 10min. It is more preferable that it is 5-25 g / 10min. When the polyethylene resin (a3) having a melt flow rate in the above range is combined with the polypropylene resin (a1), an olefinic thermoplastic elastomer excellent in mechanical strength is easily obtained.

The polyethylene resin (a3) preferably has a density of 0.880 to 0.940 g / cm ³ , more preferably 0.885 to 0.935 g / cm ³ , and 0.895 to 0.930 g / cm ^3. More preferably, it is cm ³ . The density is a value measured according to ASTM D1505. When the density is in the above range, the resulting olefinic thermoplastic elastomer layer (A) is less likely to swell even when exposed to vaporized fuel or the like, and mechanical strength and impact resistance are difficult to change. The density of the polyethylene resin (a3) is adjusted by the type of the polyethylene resin (a1) (for example, a copolymer), the preparation conditions, and the like.

  As described above, the olefinic thermoplastic elastomer is a mixture of the polypropylene resin (a1) and the ethylene copolymer rubber (a2) and, if necessary, the polyethylene resin (a3). And it can obtain by mixing the said mixture with a crosslinking agent and dynamically heat-processing by a well-known method. When the olefinic thermoplastic elastomer layer (A) includes a softener (a4) described later, a rubber other than the ethylene copolymer rubber (a2), an inorganic filler, and various additives, these are mixed as described above. Each component can be uniformly dispersed in the olefin-based thermoplastic elastomer by mixing with the body and heat-treating at the same time.

  Further, when preparing the olefin-based thermoplastic elastomer, a curing master batch in which an inorganic filler or a crosslinking agent is mixed with the ethylene copolymer rubber (a2) in advance is prepared, You may mix with resin. Furthermore, only a part of the polypropylene resin (a1) may be dynamically heat-treated, and the remaining polypropylene resin (a1) may be mixed with the resin after the dynamic heat treatment.

  Here, the crosslinking agent used for the preparation of the olefin-based thermoplastic elastomer can be a crosslinking agent generally used for the preparation of the thermosetting rubber. Specific examples of the crosslinking agent include organic peroxides, sulfur, phenol resins, amino resins, quinones or derivatives thereof, amine compounds, azo compounds, epoxy compounds, isocyanates, and the like. Among these, organic peroxides are particularly preferable.

  Specific examples of the organic peroxide include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5. -Di- (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, n- Butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert-butylperoxybenzoate, tert-butylperoxyisopropyl carbonate Diacetyl peroxide, lauroyl peroxide, include tert- butyl cumyl peroxide and the like.

  In preparing the olefin-based thermoplastic elastomer, the crosslinking agent is added in an amount of 0.001 part by mass with respect to 100 parts by mass of the total amount of the polypropylene resin (a1), the ethylene copolymer rubber (a2), and the polyethylene resin (a3). It is preferable to add 02 to 10 parts by mass. When the crosslinking agent is an organic peroxide, 0.02 to 0.02 mass with respect to 100 parts by mass of the total amount of the polypropylene resin (a1), the ethylene copolymer rubber (a2), and the polyethylene resin (a3). The amount is preferably 3 parts by mass, and more preferably 0.05 to 2 parts by mass. When the amount of the crosslinking agent is within the above range, an olefin-based thermoplastic elastomer excellent in heat resistance and the like is easily obtained.

  The dynamic heat treatment can be performed with a known apparatus. Examples of the apparatus include a mixing roll, an intensive mixer (for example, a Banbury mixer, a kneader), a single-screw or twin-screw extruder, and the like. Further, the temperature and treatment time during the heat treatment are appropriately selected according to the type of crosslinking accelerator, the desired degree of crosslinking, and the like.

  The olefinic thermoplastic elastomer layer (A) may contain a softener as necessary. Specific examples of the softener include petroleum-based substances such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, and petroleum jelly; coal tars such as coal tar and coal tar pitch; castor oil, linseed oil, rapeseed oil, Fatty oils such as soybean oil and coconut oil; waxes such as tall oil, beeswax, carnauba wax and lanolin; fatty acids such as ricinoleic acid, palmitic acid, stearic acid, barium stearate, calcium stearate or metal salts thereof; petroleum resins; Synthetic polymer materials such as coumarone indene resin and atactic polypropylene; ester plasticizers such as dioctyl phthalate, dioctyl adipate and dioctyl sebacate; microcrystalline wax; sub (factis); liquid polybutadiene; modified liquid polybutadiene; liquid thiocol; It is included.

  The amount of the softening agent is preferably 10 to 200 parts by mass, and more preferably 15 to 140 parts by mass with respect to 100 parts by mass of the above-described ethylene copolymer rubber (a2). When the above-mentioned amount of softening agent is contained in the olefinic thermoplastic elastomer, the fluidity of the olefinic thermoplastic elastomer is improved, and the heat resistance of the laminated structure is easily increased.

  Further, the olefinic thermoplastic elastomer layer (A) may contain other rubbers other than the ethylene copolymer rubber (a2) as long as the object of the present invention is not impaired. Examples of such other rubbers include butyl rubber, polyisobutylene rubber, styrene-butadiene rubber (SBR) or hydrogenated product thereof (H-SBR), styrene-butadiene block copolymer rubber (SBS) or hydrogenated product thereof. Products (SEBS), styrene / isoprene block copolymer rubber (SIS) or hydrogenated products thereof (SEPS, HV-SIS), nitrile rubber (NBR), natural rubber (NR), and silicon rubber.

  Furthermore, the olefinic thermoplastic elastomer layer (A) may contain an inorganic filler as long as the object of the present invention is not impaired. Specific examples of inorganic fillers include calcium carbonate, calcium silicate, clay, kaolin, talc, silica, diatomaceous earth, mica powder, asbestos, alumina, barium sulfate, aluminum sulfate, calcium sulfate, basic magnesium carbonate, disulfide Molybdenum, graphite, glass fiber, glass sphere, shirasu balloon, basic magnesium sulfate whisker, calcium titanate whisker, aluminum borate whisker and the like are included.

  Further, the olefinic thermoplastic elastomer layer (A) may contain various additives within a range not impairing the object of the present invention. Examples of additives include fillers, stabilizers, activators, antistatic agents, flame retardants, foaming agents, pigments, dyes and the like.

  The olefin-based thermoplastic elastomer layer (A) is produced by molding the above-mentioned olefin thermoplastic elastomer or a mixture of the olefin thermoplastic elastomer and other components into a layer having a desired thickness using a molding machine. Can do.

  The thickness (Ta) of the olefin-based thermoplastic elastomer (A) is preferably 0.5 to 0.995, and preferably 0.6 to 0.9 with respect to the thickness (Ts) of the laminated structure. More preferred. When the ratio of the thickness of the olefinic thermoplastic elastomer (A) is 0.5 or more, the impact resistance of the laminated structure is likely to increase. On the other hand, when the thickness of the olefinic thermoplastic elastomer (A) is 0.995 or less, the thickness of the adhesive layer or the semi-aromatic polyamide layer (C) is relatively increased, and the mechanical properties of the laminated structure are increased. Strength etc. increase and the fuel permeability of a laminated structure can be suppressed low. The specific thickness of the olefin-based thermoplastic elastomer (A) is preferably 100 to 3000 μm, more preferably 300 to 2000 μm, and further preferably 500 to 1500 μm.

1-2. Adhesive layer (B)
The adhesive layer (B) is a graft of propylene homopolymer and / or propylene / α-olefin copolymer (hereinafter collectively referred to as “propylene polymer”) with an unsaturated carboxylic acid or a derivative thereof. It is a layer containing a modified modified propylene polymer. The adhesive layer (B) may contain other components as required, but preferably contains 60% by mass or more of the modified propylene-based coal based on the total mass of the adhesive layer (B), and is 80% by mass. More preferably. When the amount of the modified propylene polymer is 60% by mass or more, the adhesive strength between the adhesive layer (B) and the olefinic thermoplastic elastomer layer (A) or the semi-aromatic polyamide layer (C) tends to increase.

  Here, when the propylene polymer modified with the unsaturated carboxylic acid or its derivative is a propylene / α-olefin copolymer, the carbon number of the α-olefin constituting the propylene / α-olefin copolymer is It is preferably 4 to 20, and more preferably 4 to 10. Examples of the α-olefin include ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like.

  Further, the amount of the structural unit derived from propylene in the propylene / α-olefin copolymer is preferably 75 mol% or more with respect to the total molar amount of the structural units constituting the copolymer, and is 85 mol%. More preferably. When the amount of the structural unit derived from propylene is in the above range, when the olefinic thermoplastic elastomer of the olefinic thermoplastic elastomer layer (A) includes a segment made of propylene resin, the olefinic thermoplastic elastomer layer ( The adhesive strength between A) and the adhesive layer (B) is increased.

  On the other hand, the unsaturated carboxylic acid for graft-modifying the propylene polymer is not particularly limited. Specific examples of the unsaturated carboxylic acid include (meth) acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, nadic acid (endocis-bicyclo [2.2.1]). Unsaturated carboxylic acids such as hept-5-ene-2,3-dicarboxylic acid); or derivatives of these acid halides, amides, imides, anhydrides, esters, and the like. Among these, unsaturated dicarboxylic acid or its anhydride is preferable, and more specifically, maleic acid, nadic acid or their acid anhydride is preferable. In particular, maleic anhydride is preferable from the viewpoints of availability, chemical stability, and the like.

The modified propylene polymer preferably contains 0.08 to 5 mass% of the structure derived from the unsaturated carboxylic acid or derivative thereof relative to the total amount of the modified propylene polymer, and is 0.08 to 3 mass%. More preferably, it is more preferably 0.08 to 1% by mass. When the structure derived from the unsaturated carboxylic acid or its derivative is included in the above range, the adhesiveness of the adhesive layer (B) is likely to increase. The proportion of the structure derived from the unsaturated carboxylic acid or derivative thereof contained in the modified propylene polymer can be specified by a known means such as ¹³ C-NMR measurement or ¹ H-NMR measurement. Specific conditions for NMR measurement include the following conditions.

^In the case of ¹ H-NMR measurement, an ECX400 type nuclear magnetic resonance apparatus manufactured by JEOL Ltd. is used, the solvent is deuterated orthodichlorobenzene, the sample concentration is 20 mg / 0.6 mL, the measurement temperature is 120 ° C., the observation nucleus Is ¹ H (400 MHz), the sequence is a single pulse, the pulse width is 5.12 μs (45 ° pulse), the repetition time is 7.0 seconds, and the number of integration is 500 times or more. The standard chemical shift is 0 ppm for tetramethylsilane hydrogen. For example, the same result can be obtained by setting the peak derived from residual hydrogen in deuterated orthodichlorobenzene to 7.10 ppm and setting the standard value for chemical shift. be able to. A peak such as ¹ H derived from the functional group-containing compound can be assigned by a conventional method.

^In the case of ¹³ C-NMR measurement, an ECP500 type nuclear magnetic resonance apparatus manufactured by JEOL Ltd. is used as a measuring apparatus, and a mixed solvent of orthodichlorobenzene / heavy benzene (80/20 vol%) as a solvent, measuring temperature is 120 ° C., The observation nucleus is a condition of ¹³ C (125 MHz), single pulse proton decoupling, 45 ° pulse, repetition time of 5.5 seconds, integration number of 10,000 times or more, and 27.50 ppm as a reference value for chemical shift. Assignment of various signals is performed based on a conventional method, and quantification can be performed based on an integrated value of signal intensity.

  Here, the modified propylene polymer is obtained by reacting an unsaturated carboxylic acid or a derivative thereof in a state where the propylene polymer is melted. The reaction (graft modification) of the propylene polymer with the unsaturated carboxylic acid or derivative thereof can be performed by a known method. For example, a method of reacting these in the presence of an organic peroxide may be used. The graft modification is preferably performed in the absence of a solvent from the viewpoint of the adhesiveness of the adhesive layer (B) and the like.

Here, the density of the adhesive layer (B) is 0.880 to 0.920 g / cm ³ . The density is measured according to ASTM D1505. When the density of the adhesive layer (B) is 0.880 g / cm ³ or more, the strength of the adhesive layer (B) is easily increased, and when it is 0.920 g / cm ³ or less, the adhesive layer (B) Adhesion with the semi-aromatic polyamide layer (C) tends to increase. That is, when the density of the adhesive layer (B) is within the above range, the balance between the strength and adhesiveness of the adhesive layer (B) is excellent, and the adhesive layer (B) and the olefinic thermoplastic elastomer layer (A). And the adhesion to the semi-aromatic polyamide layer (C) is likely to increase. The density of the adhesive layer (B) is adjusted by the kind of α-olefin contained in the above-mentioned propylene polymer, the amount of unsaturated carboxylic acid or its derivative contained in the modified propylene polymer, and the like.

  The adhesive layer (B) can be produced by molding the modified propylene polymer into a layer having a desired thickness using a molding machine or the like, as will be described later.

  Here, the thickness (Tb) of the adhesive layer (B) is preferably 0.005 to 0.1, more preferably 0.001 to 0.06, with respect to the thickness (Ts) of the laminated structure. It is. When the thickness ratio of the adhesive layer (B) is 0.005 or more, the interlayer adhesive force of each layer constituting the laminated structure is likely to increase. On the other hand, when the thickness of the adhesive layer (B) is 0.1 or less, the thickness of the olefin-based thermoplastic elastomer layer (A) or the semi-aromatic polyamide layer (C) becomes relatively large, and the laminated structure The mechanical strength of the body is easily increased, and the fuel permeability of the laminated structure is easily reduced. The specific thickness of the adhesive layer (B) is preferably 5 to 100 μm, more preferably 10 to 60 μm, and still more preferably 15 to 40 μm.

1-3. Semi-aromatic polyamide layer (C)
The semi-aromatic polyamide layer (C) is a layer containing a semi-aromatic polyamide resin. The semi-aromatic polyamide resin is a polyamide resin containing an aliphatic-derived structural unit and an aromatic-derived structural unit. When the laminated structure includes a semi-aromatic polyamide layer (C), the fuel of the laminated structure Permeability is reduced.

  The semi-aromatic polyamide layer (C) preferably contains 50% by mass or more, more preferably 60 to 97% by mass of the semi-aromatic polyamide resin with respect to the total mass of the semi-aromatic polyamide layer (C). 75 to 95% by mass is more preferable. When the semi-aromatic polyamide layer (C) contains 50% by mass or more of the semi-aromatic polyamide resin, the fuel permeation resistance of the laminated structure is likely to increase.

  On the other hand, the semi-aromatic polyamide layer (C) may further include a modified olefin polymer obtained by modifying an olefin polymer with a compound having a hetero atom (functional group-containing compound). When the semi-aromatic polyamide layer (C) contains a modified olefin polymer, the impact strength of the semi-aromatic polyamide layer (C) is likely to be increased, and the flexibility of the laminated structure is likely to be increased. The semi-aromatic polyamide layer (C) preferably contains 7 to 28% by mass and more preferably 5 to 25% by mass of the modified olefin polymer with respect to the total mass.

  Here, the semi-aromatic polyamide resin contained in the semi-aromatic polyamide layer (C) is obtained by polymerizing a dicarboxylic acid component and a diamine component. Specific examples of the semi-aromatic polyamide resin include 40 to 100 mol% of structural units derived from terephthalic acid [a] based on the total dicarboxylic acid component, and have 4 to 12 carbon atoms based on the total diamine structural units. Examples thereof include polyamide resins containing 60 to 100 mol% of a structural unit derived from aliphatic diamine [d].

  Further, as other specific examples of the semi-aromatic polyamide resin, a structural unit derived from terephthalic acid [a] represented by the following formula, a structural unit derived from isophthalic acid [b] represented by the following formula, and a carbon atom Examples also include polyamide resins containing a structural unit derived from an aliphatic dicarboxylic acid [c] having 4 to 10 carbon atoms and a structural unit derived from an aliphatic diamine [d] having 4 to 12 carbon atoms.

  At this time, when the total of the structural unit derived from terephthalic acid [a], the structural unit derived from isophthalic acid [b], and the structural unit derived from [c] contained in the semi-aromatic polyamide resin is 100 mol%. The content of the structural unit derived from terephthalic acid [a] is preferably 35 to 50 mol%, and the content of the structural unit derived from isophthalic acid [b] is preferably 25 to 40 mol%, more preferably The content of the structural unit derived from the aliphatic dicarboxylic acid [c] having 4 to 10 carbon atoms is preferably 30 to 35 mol%, more preferably 20 to 30 mol%. .

  Examples of the aliphatic dicarboxylic acid [c] having 4 to 10 carbon atoms include adipic acid (6 carbon atoms), suberic acid (8 carbon atoms), azelaic acid (9 carbon atoms), sebacic acid ( Chain aliphatic dicarboxylic acids such as those having 10 carbon atoms are included. The aliphatic dicarboxylic acid [c] is particularly preferably adipic acid from the viewpoints of cost, strength of the semi-aromatic polyamide layer (C), and the like.

  Moreover, a semi-aromatic polyamide resin may also contain structural units derived from dicarboxylic acids other than the dicarboxylic acids [a] to [c] (structural units derived from other carboxylic acids). However, the number of moles of structural units derived from other dicarboxylic acids is preferably 5% or less with respect to the total number of moles of [a] to [c]. Examples of other dicarboxylic acids include aromatic dicarboxylic acids such as 2-methylterephthalic acid and naphthalenedicarboxylic acid, furandicarboxylic acids such as 2,5-furandicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,3- Examples include alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and aliphatic dicarboxylic acids having 11 or more phthalic carbon atoms.

  On the other hand, the semi-aromatic polyamide resin preferably includes a structural unit derived from an aliphatic diamine [d] having 4 to 12 carbon atoms as a structural unit derived from diamine. The aliphatic diamine [d] may be a linear aliphatic diamine or a chain aliphatic diamine having a side chain. Examples of the aliphatic diamine [d] include 1,4-diaminobutane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diamino. Linear aliphatic diamines such as decane, 1,11-diaminoundecane, 1,12-diaminododecane; 2-methyl-1,5-diaminopetane, 2-methyl-1,6-diaminohexane, 2-methyl-1 , 7-diaminoheptane, 2-methyl-1,8-diaminooctane, 2-methyl-1,9-diaminononane, 2-methyl-1,10-diaminodecane, 2-methyl-1,11-diaminoundecane, etc. A chain aliphatic diamine having a side chain is included.

  The aliphatic diamine [d] is preferably a diamine having 6 to 9 carbon atoms, more preferably hexamethylene diamine (6 carbon atoms) or nonane diamine (9 carbon atoms).

  The semi-aromatic polyamide resin may contain a structural unit derived from diamine other than the aliphatic diamine [d], but the number of moles thereof is preferably 10 mol% or less with respect to the number of moles of [d]. . Examples of other diamines include aromatic diamines such as metaxylenediamine, and alicyclic diamines such as 1,4-cyclohexanediamine and 1,3-cyclohexanediamine.

  Here, the melt tension at the “melting end temperature (T) +10 (° C.)” of the semi-aromatic polyamide resin included in the semi-aromatic polyamide layer (C) is preferably 3 to 30 mN, and 5 to 25 mN. More preferably. The melt tension of the semi-aromatic polyamide resin is “CAPILROGRAPH 1B” manufactured by Toyo Seiki, with a capillary diameter of 1.0 mmφ, a capillary length of 20 mm, a winding speed of 10 m / min, and a melting end temperature (T) of + 10 ° C. Measured. When the melt tension (melt tension: mN) is in the above range, the shape-retaining property of the semi-aromatic polyamide layer (C) obtained by molding the semi-aromatic polyamide resin can be improved, and the laminated structure is produced. Sometimes drawdown is unlikely to occur. A method for measuring the melting end temperature (T) will be described later. The melt tension of the semi-aromatic polyamide resin is mainly adjusted by the molecular weight and the ratio of the structural units derived from [a] to [c] contained in the semi-aromatic polyamide resin.

  As described above, when the semi-aromatic polyamide resin includes a structural unit derived from [a] and a structural unit derived from [b], the molar ratio of these structural units ([a] / [b]) is 65 It is preferable that it is / 35-50 / 50. According to terephthalic acid [a], crystallinity can be imparted to the semi-aromatic polyamide resin to increase the heat resistance of the semi-aromatic polyamide layer (C), but the melt tension of the semi-aromatic polyamide resin is increased. hard. On the other hand, according to isophthalic acid [b], the melt tension of the semiaromatic polyamide resin can be increased while maintaining the heat resistance of the semiaromatic polyamide layer (C).

  When the semi-aromatic polyamide includes a structural unit derived from [c] and a structural unit derived from [b], their molar ratio ([c] / [b]) is 30/70 to 50/50. preferable. According to the aliphatic dicarboxylic acid [c], the semi-aromatic polyamide resin can be rendered amorphous (lowering the melting end temperature (T)) to improve the molding processability. It is difficult to increase the melt tension of the resin. On the other hand, according to isophthalic acid [b], the melt tension of the semi-aromatic polyamide resin can be increased while maintaining the heat resistance of the semi-aromatic polyamide resin.

  That is, when the ratio of the structural units derived from [a] to [c] in the semi-aromatic polyamide resin is in the above range, the melt tension of the semi-aromatic polyamide resin is increased. Here, PA6T (polyamide obtained from terephthalic acid and hexamethylenediamine) and PA66 (polyamide obtained from adipic acid and hexamethylenediamine) are known to have low melt tension. Since both PA6T and PA66 contain dicarboxylic acid or diamine having high linearity as constituent components, they are highly rigid and have little entanglement between polymer chains. Therefore, it is presumed that the tension during melting is relatively low.

  On the other hand, the amount of structural units derived from [a] to [c] is within the above range, and in particular, the molar ratio ([a] / [b]) and the molar ratio ([c] / [b]) are appropriate. It is thought that the tension at the time of melting increases by setting to. Isophthalic acid [b] has a bent structure rather than linear. Therefore, by including isophthalic acid [b] to some extent, the rigidity of the polymer chain of the semi-aromatic polyamide resin is relaxed and the polymer chains are easily entangled. And it is guessed that the tension | tensile_strength at the time of the melt | dissolution of a semi-aromatic polyamide resin increases.

  Here, the intrinsic viscosity [η] of the semi-aromatic polyamide resin included in the semi-aromatic polyamide layer (C) is preferably 0.7 to 1.6 dl / g, and 0.8 to 1.2 dl / g. More preferably. The intrinsic viscosity [η] is measured in a temperature of 25 ° C. and 96.5% sulfuric acid. When the intrinsic viscosity [η] is 0.7 dl / g or more, the mechanical strength of the resulting semi-aromatic polyamide layer (C) increases. On the other hand, the above-described melt tension tends to fall within a desired range. In addition, when the intrinsic viscosity [η] is 1.6 dl / g or less, the balance between fluidity and mechanical strength during molding is excellent. In order to make the intrinsic viscosity [η] of the semi-aromatic polyamide resin within the above range, it is preferable to react a dicarboxylic acid component and a diamine component by blending a molecular weight regulator or the like in the reaction system. As the molecular weight modifier, monocarboxylic acid and monoamine can be used.

  Examples of monocarboxylic acids used as molecular weight modifiers include aliphatic monocarboxylic acids having 2 to 30 carbon atoms; aromatic monocarboxylic acids; and alicyclic monocarboxylic acids. In addition, the aromatic monocarboxylic acid and the alicyclic monocarboxylic acid may have a substituent in the cyclic structure portion. For example, examples of aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, oleic acid and linoleic acid Is included. Examples of the aromatic monocarboxylic acid include benzoic acid, toluic acid, naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid and phenylacetic acid. Examples of the alicyclic monocarboxylic acid include cyclohexanecarboxylic acid.

  The molecular weight modifier is added to a reaction system in which a dicarboxylic acid and a diamine are reacted to form a polyamide, and is usually 0 to 0.07 mol, preferably 0 to 0.0. It is preferably added in an amount of 05 mol. By using the molecular weight adjusting agent in such an amount, at least a part of the molecular weight adjusting agent is incorporated into the polyamide, whereby the molecular weight of the polyamide, that is, the intrinsic viscosity [η] is adjusted within a desired range.

  The heat of fusion (ΔH) of the semi-aromatic polyamide resin is preferably 20 to 40 mJ / mg, and more preferably 20 to 35 mJ / mg. The heat of fusion becomes an index of the crystallinity of polyamide, and the higher the heat of fusion, the higher the crystallinity, and the lower the heat of fusion, the lower the crystallinity. For example, when the structural units derived from terephthalic acid [a] are arranged as blocks, the crystallinity of the semi-aromatic polyamide resin is excessively increased, and as a result, the heat of fusion (ΔH) is higher than 40 mJ / mg. Therefore, in the semi-aromatic polyamide resin, it is preferable that the structural units derived from the dicarboxylic acids [a] to [c] are arranged as randomly as possible.

  It is preferable that melting | fusing point (Tm) calculated | required by differential scanning calorimetry (DSC) of a semi-aromatic polyamide resin is 230 degreeC or more. A sample of semi-aromatic polyamide resin was heated using a DSC7 manufactured by PerkinElmer, temporarily held at 320 ° C. for 5 minutes, then cooled to 23 ° C. at a rate of 10 ° C./minute, and then increased at 10 ° C./minute. Warm up. The endothermic peak based on melting at this time may be the melting point (Tm) of the polyamide. However, the temperature corresponding to the peak top of the endothermic peak observed in the differential scanning calorimetry may not be clear.

  The melting end temperature (T) determined by differential scanning calorimetry (DSC) of the semi-aromatic polyamide resin is preferably 250 to 300 ° C. The melting end temperature (T) refers to the temperature at which the endotherm due to melting disappears in differential scanning calorimetry similar to the measurement of the melting point. Specifically, it refers to the temperature at which the endothermic peak observed in differential scanning calorimetry returns to the baseline. The melting end temperature (T) can be lowered by arranging the structural units derived from [a] to [c] in the semi-aromatic polyamide resin as randomly as possible.

  Moreover, it is preferable that the melt flow rate (melting completion temperature (T) +10 degreeC, 2.16 kg) measured based on ASTM D1238 of a semi-aromatic polyamide resin is 1-50 g / 10min.

  The aforementioned semi-aromatic polyamide resin can be prepared based on a known production method as a conventional production method of a semi-aromatic polyamide resin. For example, dicarboxylic acids [a] to [c] and diamine [d] can be produced by polycondensation in a homogeneous solution. More specifically, the low-order condensate is obtained by heating dicarboxylic acid and diamine in the presence of a catalyst as described in WO 03/085029. Then, a desired semi-aromatic polyamide resin is produced by applying a shear stress to the melt of the low-order condensate and performing polycondensation.

  On the other hand, the modified olefin polymer contained in the semi-aromatic polyamide layer (C) is obtained by modifying an olefin polymer with a compound containing a hetero atom (functional group-containing compound). The compound containing a hetero atom means a compound having a functional group containing a hetero atom. Examples of the functional group containing a hetero atom include a carboxylic acid group, a carboxylic anhydride group, an ester group, an ether group, an aldehyde group, A ketone group is included.

  On the other hand, examples of the olefin polymer modified with the functional group-containing compound include an ethylene polymer, a propylene polymer, a butene polymer, and a copolymer thereof. A particularly preferred olefin polymer is a copolymer of ethylene and an α-olefin having 3 or more carbon atoms (ethylene / α-olefin copolymer).

  The α-olefin preferably has 3 to 10 carbon atoms, and examples thereof include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene. Specific examples of the ethylene / α-olefin copolymer include an ethylene / propylene copolymer, an ethylene / 1-butene copolymer, an ethylene / 1-hexene copolymer, an ethylene / 1-octene copolymer, 4-methyl-1-pentene copolymer and the like are included. Among these, an ethylene / propylene copolymer, an ethylene / 1-butene copolymer, an ethylene / 1-hexene copolymer, and an ethylene / 1-octene copolymer are preferable.

  The ethylene / α-olefin copolymer preferably contains 70 to 99.5 mol% of structural units derived from ethylene with respect to the total amount of structural units constituting the ethylene / α-olefin copolymer, and 80 to 99 More preferably, it is mol%. On the other hand, the structural unit derived from the α-olefin is preferably contained in an amount of 0.5 to 30 mol%, and preferably 1 to 20 mol%, based on the total amount of the structural units constituting the ethylene / α-olefin copolymer. Is more preferable.

  The melt flow rate (190 ° C., 2.16 kg load) measured in accordance with ASTM D1238 of the ethylene / α-olefin copolymer is preferably 0.01 to 20 g / 10 min, more preferably 0. 0.05 to 20 g / 10 min.

  The production method of the ethylene / α-olefin copolymer is not particularly limited, and ethylene and one or more α-olefins having 3 to 10 carbon atoms are copolymerized in the presence of a Ziegler catalyst or a metallocene catalyst. The manufacturing method can be illustrated. In particular, a production method using a metallocene catalyst is suitable.

  In addition, the functional group-containing compound for modifying the olefin polymer is not particularly limited as long as it is a compound having a functional group containing a halogen atom as described above. However, it is preferable that the functional group-containing compound is an unsaturated carboxylic acid or a derivative thereof. It is preferable from the viewpoint. Specific examples of the unsaturated carboxylic acid or its derivative include acrylic acid, methacrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, nadic acid (endocis) -Unsaturated carboxylic acids such as -bicyclo [2,2,1] hept-5-ene-2,3-dicarboxylic acid) and derivatives thereof such as acid halides, amides, imides, acid anhydrides, esters, etc. It is. Among these, unsaturated dicarboxylic acids or acid anhydrides thereof are preferable, and maleic acid, nadic acid, or acid anhydrides thereof are particularly preferable.

  A particularly preferred compound is maleic anhydride. Maleic anhydride has a relatively high reactivity with the olefin polymer before modification, hardly causes polymerization between maleic anhydrides, and tends to be stable as a basic structure. For this reason, there are various advantages such as obtaining a modified olefin polymer having a stable quality.

  The modified olefin polymer is obtained by graft-modifying the above-mentioned olefin polymer with a functional group-containing compound. Hereinafter, an ethylene / α-olefin copolymer will be described with an example of graft modification with an unsaturated carboxylic acid or a derivative thereof. The graft modification of the ethylene / α-olefin copolymer can be carried out by a known method. For example, an ethylene / α-olefin copolymer is dissolved in an organic solvent, and an unsaturated carboxylic acid or a derivative thereof and a radical initiator are added to the obtained solution, and the temperature is usually 60 to 350 ° C., preferably 80 to 190 ° C. The method of making it react at temperature for 0.5 to 15 hours, Preferably it is 1 to 10 hours can be illustrated.

  The organic solvent for dissolving the ethylene / α-olefin copolymer is not particularly limited, but aromatic hydrocarbon solvents such as benzene, toluene and xylene; aliphatic hydrocarbon solvents such as pentane, hexane and heptane, etc. Can be mentioned.

  Further, as another graft modification method of ethylene / α-olefin copolymer, ethylene / α-olefin copolymer and unsaturated carboxylic acid or derivative thereof are preferably used in an extruder or the like in the absence of a solvent. The method of making it react is mentioned. The reaction conditions in this case are such that the reaction temperature is usually not lower than the melting point of the ethylene / α-olefin copolymer, specifically 100 to 350 ° C. The reaction time can usually be 0.5 to 10 minutes.

  In order to efficiently carry out graft modification reaction of a compound having a functional group such as an unsaturated carboxylic acid on the ethylene / α-olefin copolymer, it is preferable to perform a modification reaction in the presence of a radical initiator. Examples of radical initiators include organic peroxides, organic peroxides such as benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl 14 peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di (peroxide benzoate) Hexin-3,1,4-bis (t-butylperoxyisopropyl) benzene, lauroyl peroxide, t-butylperacetate, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,2, 5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylperbenzoate, t-butylperphenylacetate, t-butylperisobutyrate, t-butylper-sec-octoate, t-butylper Pivalate, cumyl perpivalate and t Butyl peroxide diethyl acetate; azo compounds such as azobisisobutyronitrile, dimethyl azoisobutyrate is used. Among these, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,2,5-dimethyl-2,5-di (t Dialkyl peroxides such as -butylperoxy) hexane and 1,4-bis (t-butylperoxyisopropyl) benzene are preferred. The radical initiator is usually used at a ratio of 0.001 to 1 part by mass with respect to 100 parts by mass of the ethylene / α-olefin copolymer before modification.

The modified olefin polymer preferably has a density of 0.80 to 0.95 g / cm ³ , more preferably 0.85 to 0.90 g / cm ³ . The density is measured according to ASTM D1505.

  Further, the intrinsic viscosity [η] of the modified olefin polymer measured in a 135 ° C. decalin (decahydronaphthalene) solution is preferably 0.5 to 4.0 dl / g, and preferably 1.0 to 3 dl. / G is more preferable, and 1.5 to 3 dl / g is more preferable. When the intrinsic viscosity [η] is within the above range, the strength of the semi-aromatic polyamide layer (C) is likely to increase.

  The intrinsic viscosity [η] in decalin at 135 ° C. of the modified olefin polymer can be measured as follows based on a conventional method. 20 mg of a sample is dissolved in 15 ml of decalin, and the specific viscosity (ηsp) is measured in an atmosphere of 135 ° C. using an Ubbelohde viscometer. After adding 5 ml of decalin to the decalin solution and diluting, the same specific viscosity is measured. Based on the measurement result obtained by repeating this dilution operation and viscosity measurement twice more, the “ηsp / C” value when the concentration (C) is extrapolated to zero is defined as the intrinsic viscosity [η].

  The modified olefin polymer preferably contains 0.3 to 1.5% by mass of the structure derived from the functional group-containing compound with respect to the total amount of the modified olefin polymer, and is preferably 0.4 to 1.1% by mass. More preferably. If the structure derived from the functional group-containing compound is too small, the effect of improving the toughness of the semi-aromatic polyamide layer (C) may be low.

The amount of the structure derived from the functional group-containing compound contained in the modified olefin polymer is determined by the charge ratio when the olefin polymer before modification and the compound having a functional group are reacted, ¹³ C-NMR measurement or ¹ H- It can be specified by a known means such as NMR measurement. Specific NMR measurement conditions may be the same as the measurement of the structure derived from the unsaturated carboxylic acid or derivative thereof contained in the modified propylene polymer contained in the adhesive layer (B).

  Here, the melt tension of the semi-aromatic polyamide layer (C) is preferably 20 to 90 mN, and more preferably 30 to 70 mN. The melt tension of the semi-aromatic polyamide layer (C) means the melt tension at the “melting end temperature (T) +10 (° C.)” of the semi-aromatic polyamide resin described above. The melt tension of the semi-aromatic polyamide layer (C) is as follows: Capillary diameter 1.0 mmφ, capillary length 20 mm, winding speed 10 m / min, melting end temperature (T) + 10 ° C. Measured.

  The melt flow rate (melting end temperature (T) + 10 ° C., 2.16 kg) measured in accordance with ASTM 1238 of the mixture of the semi-aromatic polyamide resin and the modified olefin polymer is 0.1 to It is preferably 20 g / 10 minutes. The melt flow rate of the mixture means a melt flow rate with a load of 5 kg “at the melting end temperature (T) +10 (° C.)” of the semi-aromatic polyamide resin contained therein.

  The flexural modulus of the semi-aromatic polyamide layer (C) is preferably 400 to 2100 MPa, and more preferably 800 to 2000 MPa. Further, the bending strength of the semi-aromatic polyamide layer (C) is preferably 40 to 200 Ma, and more preferably 60 to 150 MPa.

The bending elastic modulus and bending strength of the semi-aromatic polyamide layer (C) are as follows. The bending elastic modulus of a test piece (length 64 mm, width 6 mm, thickness 0.8 mm) molded using an injection molding machine under the following conditions: And bending strength.
Molding machine: Sodick Plustech Co., Ltd. Tupar TR40S3A
Molding machine cylinder temperature: melting end temperature (T) + 10 ° C., mold temperature: 40 ° C.

  The molded test piece is allowed to stand for 24 hours in a nitrogen atmosphere at a temperature of 23 ° C., and then treated in an oven at 150 ° C. for 2 hours. Next, a bending test is performed in an atmosphere of a temperature of 23 ° C. and a relative humidity of 50% with a bending tester: AB5 manufactured by INTESCO, a span of 26 mm, a bending speed of 5 mm / min, and a bending elastic modulus and strength are measured.

  The semi-aromatic polyamide layer (C) can be obtained by mixing and molding a semi-aromatic polyamide resin and a modified olefin polymer. The semi-aromatic polyamide resin and the modified olefin polymer are mixed by mixing the semi-aromatic polyamide resin and the modified olefin polymer by a known method such as a Henschel mixer, a V blender, a ribbon blender, or a tumbler blender. It can be carried out by a method, or a method of further granulating or pulverizing after mixing with a single screw extruder, a multi-screw extruder, a kneader, a Banbury mixer or the like after mixing.

  In addition, a semi-aromatic polyamide layer (C) may contain arbitrary additives as needed in the range which does not impair the objective of invention with a semi-aromatic polyamide resin and a modified olefin type polymer. Examples of optional additives include antioxidants (phenols, amines, sulfurs, phosphorus, etc.), fillers (clay, silica, alumina, talc, kaolin, quartz, mica, graphite, etc.), heat resistant stability Agents (lactone compounds, vitamin Es, hydroquinones, copper halides, iodine compounds, etc.), light stabilizers (benzotriazoles, triazines, benzophenones, benzoates, hindered amines, oxanilides, etc.), other polymers (Olefins such as polyolefins, ethylene / propylene copolymer, ethylene / 1-butene copolymer, olefin copolymers such as propylene / 1-butene copolymer, polystyrene, polyamide, polycarbonate, polyacetal, poly Sulphone, polyphenylene oxide, fluorine resin, silicone resin LCP, etc.), flame retardants (bromine, chlorine, phosphorus, antimony, inorganic, etc.), fluorescent brighteners, plasticizers, thickeners, antistatic agents, release agents, pigments, crystal nucleating agents, various Known compounding agents are included.

  The amount of the optional additive contained in the semi-aromatic polyamide layer (C) varies depending on the type of the component, but when the total of the semi-aromatic polyamide resin and the modified olefin polymer is 100% by mass, it is 0. It is preferable that it is -10 mass%, More preferably, it is 0-5 mass%, More preferably, it is 0-1 mass%.

  Here, the ratio of the thickness (Tc) of the semi-aromatic polyamide layer (C) is preferably 0.05 to 0.4, more preferably 0.05 to the thickness (Ts) of the laminated structure. ~ 0.3. When the ratio of the thickness of the semi-aromatic polyamide layer (C) is 0.05 or more, the fuel permeability of the laminated structure is reduced. On the other hand, when the thickness ratio of the semi-aromatic polyamide layer (C) is 0.4 or less, the cost of the laminated structure can be easily reduced. Here, the specific thickness of the semi-aromatic polyamide layer (C) is preferably 10 to 400 μm, and more preferably 50 to 300 μm.

1-4. Other Layers The laminated structure of the present invention is a range other than the above-described olefinic thermoplastic elastomer layer (A), adhesive layer (B), and semi-aromatic polyamide layer (C) as long as the effects of the present invention are not impaired. Layers may be included. For example, a conductive layer having conductivity may be separately laminated on the surface of the laminated structure on the semi-aromatic polyamide layer (C) side, that is, the innermost layer.

  If the innermost layer of the laminated structure is insulative, static electricity may accumulate in the laminated structure when liquid fuel or the like flows inside the hollow structure (for example, a tube). This static electricity can ignite the fuel. On the other hand, when a conductive layer is laminated on the innermost layer, static electricity is hardly accumulated even if liquid fuel or the like flows inside the hollow structure.

  Examples of such a conductive layer include resins used for tubes for automobile fuel piping (for example, aliphatic polyamides such as polyamide 6, polyamide 11, and polyamide 12; polyphenylene sulfide resin, polymetaxylylene adipamide, semi-solid). An aromatic polyamide resin, a polyester resin, etc.) and a conductive filler may be used. The shape of the conductive filler is not particularly limited, and may be granular, flaky, fibrous, or the like.

  Examples of the particulate filler include carbon black, graphite and the like. Examples of the flaky filler include aluminum flakes, nickel flakes, nickel-coated mica and the like. Examples of fibrous fillers include carbon fibers, carbon-coated ceramic fibers, carbon whiskers, aluminum fibers, copper fibers, brass fibers, and stainless steel fibers. The conductive filler is particularly preferably carbon black from the standpoint of availability and conductivity. In particular, acetylene black and furnace black (Ketjen black) are preferably used.

  It is preferable that the quantity of the conductive filler which a conductive layer contains is 3-35 mass% with respect to the total mass of a conductive layer.

The conductivity of the conductive layer is preferably 10 ⁸ Ω / square or less, more preferably 10 ⁶ Ω / square or less.

1-5. Production method of laminated structure The production method of the laminated structure of the present invention is not particularly limited, and may be a general thermoplastic resin molding machine, for example, an extrusion molding machine, a blow molding machine, a compression molding machine, an injection molding machine, or the like. The above-mentioned olefinic thermoplastic elastomer layer (A) and semi-aromatic polyamide layer (C) may be separately formed, and these may be bonded together with the adhesive layer (B). Also, for example, an olefinic thermoplastic elastomer layer (A) or an adhesive layer (B) by a co-extrusion molding method (T-die extrusion, inflation extrusion, blow molding, profile extrusion, extrusion coating, etc.) or a layered injection molding method. ) And the semi-aromatic polyamide layer (C) may be simultaneously molded and laminated.

  After laminating the olefinic thermoplastic elastomer layer (A), the adhesive layer (B), and the semi-aromatic polyamide layer (C), heating may be performed as necessary. The residual strain at the time of manufacturing the laminated structure is removed by heating.

  Moreover, you may shape | mold into the shape of various hollow structures, such as a tube shape, a hose shape, and a bottle shape, at the time of the said shaping | molding. Moreover, after shape | molding in a film form or a sheet form, a shaping | molding process may be performed and a hollow structure may be obtained.

2. Hollow structure body Examples of the molded article made of the laminated structure of the present invention include an automobile fuel piping tube or hose, an automobile cooling system piping tube or hose, an automobile radiator hose, a brake hose, an air conditioner hose, an electric wire covering material, and an optical fiber. Tubes such as covering materials, hoses, agricultural films, linings, architectural interior materials (wallpapers, etc.), films such as laminated steel sheets, sheets, automobile radiator tanks, chemical bottles, chemical tanks, chemical containers, gasoline tanks, etc. Examples include tanks. Since the laminated structure of the present invention has low fuel permeability, it is particularly useful as a tube or hose for automobile fuel piping. In addition, the laminated structure of the present invention has high flexibility and is useful as a tube or hose for automobile cooling system piping.

(Automotive fuel piping tubes or hoses, and automotive cooling system piping tubes or hoses)
The tubes and hoses for automobile fuel pipes or cooling pipes may be cylindrical, straight pipes, or some or all of them may be corrugated, bellows, accordion, etc. Further, it may be processed into an L shape, a U shape, or the like.

  The semi-aromatic polyamide layer (C) included in the laminated structure of the present invention has low fuel permeability. Therefore, various fuels (for example, gasoline, alcohol-mixed gasoline (gasohol), alcohol, hydrogen, light oil, biodiesel fuel, dimethyl ether, LPG, CNG, etc.) flowing inside the automobile fuel pipe or fuel pipe hose are tubes. It is difficult to be released outside the hose. In addition, as described above, since the laminated structure of the present invention has high mechanical strength, even if the pressure inside the tube or hose increases, they are not easily damaged. Furthermore, even if the thickness of the semi-aromatic polyamide layer (C) is thin, sufficient strength can be obtained, and further the fuel permeability can be reduced, so that the cost of various piping tubes or various piping hoses can be reduced. it can. Further, the laminated structure of the present invention is very useful as various pipes in an engine room because it can be easily processed into a desired shape and has high impact resistance and mechanical strength.

  Here, epichlorohydrin rubber in consideration of the abrasion of the stone, the wear with other parts, and the flame resistance, if necessary, on all or part of the outer periphery of the tube or hose for automobile fuel piping or cooling system piping of the present invention, NBR, a mixture of NBR and polyvinyl chloride, chlorosulfonated polyethylene rubber, chlorinated polyethylene rubber, acrylic rubber (ACM), chloroprene rubber (CR), ethylene-propylene rubber (EPR), ethylene-propylene-diene rubber (EPDM), A solid or sponge-like protective member (protector) composed of a rubber mixture of NBR and EPDM, a thermoplastic elastomer such as vinyl chloride, olefin, ester or amide may be further disposed.

  In the following, the present invention will be described with reference to examples. By way of example, the scope of the invention is not construed as limiting.

1. 1. Preparation of materials 1-1. Preparation of olefinic thermoplastic elastomer The melt elongation of the following olefinic thermoplastic elastomers was measured by the following method.
Using a capillary rheometer 1C manufactured by Toyo Seiki Seisakusho, the take-up speed was changed under the following conditions in accordance with JIS K7199, and the take-up speed at the time of yarn breakage was defined as melt elongation.
(Measurement conditions in capillary rheometer)
Strand length: 10mm
Orifice hole diameter: 1 mm
Melting temperature: 290 ° C
Crosshead speed: 50mm / min

(1) Preparation of Olefin Thermoplastic Elastomer (A1) Preparation of Curing Masterbatch (a-1) Ethylene / Propylene / 5-Ethylidene-2-norbornene Copolymer Rubber (Intrinsic Viscosity [η] = 3.34 dl / G, ethylene component content = 77 mol%, diene component content = 1.3 mol%, oil extended amount: 40 parts by mass with respect to 100 parts by mass of rubber, iodine value = 13, Mooney viscosity [ML1 + 4 (125 ° C) = 51) Laboplast mill (75C100, 140 parts by mass, 30 parts by mass of brominated phenolic resin (Tactrol 250-III, manufactured by Taoka Chemical Co., Ltd.) and 100 parts by mass of talc (Mistrone Vapor Talc, manufactured by Nippon Mystron) Kneading for 5 minutes at a set temperature of 70 ° C. and a screw speed of 30 to 70 rpm so as not to exceed 100 ° C. A master batch for curing was obtained. The obtained master batch for curing was pelletized by a pelletizer.

Preparation of resin composition (a-2) Ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber (Intrinsic viscosity [η] = 4.1 dl / g, ethylene component content = 69 mol%, diene component content = 2.1 mol%, oil extended amount: 48 parts by mass with respect to 100 parts by mass of rubber, iodine value = 22, Mooney viscosity [ML1 + 4 (125 ° C.) = 70) 148 parts by mass, polypropylene (homotype, 230 ° C., ASTM D1238) 47 parts by mass of the melt flow rate (230 ° C., 2.16 kg load) = 2 g / 10 min, melting point = 160 ° C., density = 0.903 g / cm ³ ) measured according to The mixture was kneaded for 1 minute at a set temperature of 170 ° C. and a screw rotation speed of 30 rpm to obtain a resin composition (a-2).

Mixing of components and dynamic crosslinking 36 parts by mass of the curing masterbatch (a-1) was added to 195 parts by mass of the resin composition (a-2), and after 10 seconds, 1 part by mass of zinc oxide and stearin 1 part by weight of acid was further added. And it knead | mixed for 6 minutes at 90 rpm of screw rotation speed, and obtained olefin type thermoplastic elastomer A1. The melt elongation of the obtained olefinic thermoplastic elastomer A1 was 6.4 m / min.

(2) Preparation of olefin-based thermoplastic elastomer (A2) Polypropylene (propylene homopolymer) pellets (melt flow rate measured in accordance with ASTM D1238 (230 ° C., 2.16 kg load)) = 20 g / 10 min. 30 parts by mass of density = 0.903 g / cm ³ ) and ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber pellets (ethylene / propylene (molar ratio) = 80/20, iodine value = 13, [ Mooney viscosity ML1 + 4] (125 ° C.) = 65) 70 parts by mass and softener (Diana Process Oil (registered trademark) PW-380, manufactured by Idemitsu Kosan Co., Ltd.) 30 parts by mass with a Banbury mixer in a nitrogen atmosphere, 180 The mixture was kneaded at 5 ° C for 5 minutes. Then, the roll was passed and the pellet was manufactured with the sheet cutter.
To 130 parts by mass of the pellets, 0.3 parts by mass of organic peroxide (2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane) and 0.4 parts by mass of divinylbenzene were added, and Henschel was added. Mix thoroughly in a mixer. Thereafter, the mixture was fed to a twin screw extruder and subjected to dynamic heat treatment at 220 ° C.
Further, 100 parts by mass of the pellets and 25 parts by mass of the above-mentioned propylene homopolymer pellets were fed into a twin-screw extruder and extruded at 220 ° C. to obtain olefin-based thermoplastic elastomer A2 pellets. The melt elongation of the obtained olefinic thermoplastic elastomer A2 was 3.1 m / min.

(3) Preparation of olefin-based thermoplastic elastomer (A3) Polypropylene (propylene homopolymer) pellets (melt flow rate measured in accordance with ASTM D1238 (230 ° C., 2.16 kg load)) = 20 g / 10 min. Density = 0.903 g / cm ³ ) 30 parts by mass, ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber pellets (ethylene / propylene (molar ratio) = 80/20, iodine value = 13, [Mooney Viscosity ML1 + 4] (125 ° C.) = 65) 70 parts by mass and softener (Diana Process Oil (registered trademark) PW-380, manufactured by Idemitsu Kosan Co., Ltd.) 30 parts by mass in a nitrogen atmosphere at 180 ° C. For 5 minutes. Thereafter, a roll was passed through to produce pellets by a sheet cutter.
To 130 parts by mass of the pellets, 0.3 parts by mass of organic peroxide (2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane) and 0.4 parts by mass of divinylbenzene were added, and Henschel was added. Mix thoroughly in a mixer. Thereafter, the mixture was fed to a twin screw extruder and subjected to dynamic heat treatment at 220 ° C. The melt elongation of the obtained olefinic thermoplastic elastomer A3 was 0.3 m / min.

(4) Preparation of Olefin Thermoplastic Elastomer (A4) In the preparation of the above olefin thermoplastic elastomer (A3), the amount of propylene homopolymer pellets was 50 parts by mass, and ethylene / propylene / 5-ethylidene-2 -Preparation was carried out in the same manner except that the amount of the norbornene copolymer rubber was 50 parts by mass to obtain an olefinic thermoplastic elastomer A3. The melt elongation of the resulting olefinic thermoplastic elastomer A4 was 0.6 m / min.

1-2. Preparation of modified olefin copolymer (1) Preparation of modified propylene / ethylene copolymer (B1) Isotactic propylene / ethylene copolymer having a block of propylene and ethylene obtained using a Ziegler-Natta catalyst. 2 parts by mass (propylene: ethylene = 97.3: 2.7 (molar ratio)) and 1.8 parts by mass of maleic anhydride were mixed with a tumbler blender. The mixture was extruded at 230 ° C. using a screw having a diameter of 40 mm and an effective length of 1120 mm to obtain a modified propylene / ethylene copolymer (B1) grafted with maleic anhydride. The density of the modified propylene / ethylene copolymer (B1) measured according to ASTM D1505 is 0.890 g / cm ³ , and the melt flow rate (230 ° C., 2.16 kg) measured according to ASTM D1238. The load was 6 g / 10 minutes. Moreover, the acid modification rate measured by NMR was 0.6 mass%.

(2) Preparation of modified ethylene / 4-methyl-1-pentene copolymer (B2) Copolymer of ethylene / 4-methyl-1-pentene having a density of 0.930 g / cm ^{3 using} 4-methyl-1-pentene as a comonomer To the polymer, 0.10% by mass of maleic anhydride was mixed with a tumbler blender. The mixture was extruded at 230 ° C. using a screw having a diameter of 40 mm and an effective length of 1120 mm to obtain a modified ethylene / 4-methyl-1-pentene copolymer (B2) grafted with maleic anhydride. The density of the modified ethylene / 4-methyl-1-pentene copolymer (B2) measured according to ASTM D1505 was 0.930 g / cm ³ . Moreover, the acid modification rate measured by NMR was 0.1 mass%.

1-3. Preparation of semi-aromatic polyamide resin composition (1) Preparation of semi-aromatic polyamide resin (c1) (PA6TI66) 1986 g (12.0 mol) of terephthalic acid, 2800 g (24.1 mol) of 1,6-hexanediamine, isophthal 1390 g (8.4 mol) of acid, 524 g (3.6 mol) of adipic acid, 36.5 g (0.3 mol) of benzoic acid, 5.7 g of sodium hypophosphite-hydrate and 545 g of distilled water The mixture was placed in a 13.6 L autoclave and purged with nitrogen. The mixture was heated and stirring was started from 190 ° C., and the internal temperature was raised to 250 ° C. over 3 hours. At this time, the internal pressure of the autoclave was increased to 3.03 MPa. The reaction was continued for 1 hour as it was, and then discharged from the spray nozzle installed at the bottom of the autoclave to extract the low condensate. Then, after cooling to room temperature, it grind | pulverized to the particle size of 1.5 mm or less with the grinder, and it dried at 110 degreeC for 24 hours. The obtained low condensate had a water content of 4100 ppm and an intrinsic viscosity [η] of 0.15 dl / g. Next, this low condensate was put into a shelf type solid phase polymerization apparatus, and after nitrogen substitution, the temperature was raised to 180 ° C. over about 1 hour and 30 minutes. Thereafter, the reaction was performed for 1 hour 30 minutes, and the temperature was lowered to room temperature. The intrinsic viscosity [η] of the obtained polyamide was 0.20 dl / g. After that, in a twin screw extruder with a screw diameter of 30 mm and L / D = 36, melt polymerization was performed at a barrel set temperature of 330 ° C., a screw rotation speed of 200 rp, and a resin supply rate of 6 Kg / h, and a melting point was 266 ° C. and an intrinsic viscosity. A semi-aromatic polyamide resin (c1) having [η] of 1.05 dl / g was prepared.

(2) Preparation of semi-aromatic polyamide resin (c2) (PA9T) 3971 g (23.9 mol) of terephthalic acid, 1907 g (12.0 mol) of 1,9-nonanediamine, 1907 g of 2-methyl-1,8-octanediamine (12.0 mol), 36.5 g (0.3 mol) of benzoic acid, 5.7 g of sodium hypophosphite-hydrate, and 780 g of distilled water were placed in an autoclave having an internal volume of 13.6 L and purged with nitrogen. The mixture was heated and stirring was started from 190 ° C., and the internal temperature was raised to 250 ° C. over 3 hours. At this time, the internal pressure of the autoclave was increased to 3.03 MPa. The reaction was continued for 1 hour as it was, and then discharged from the spray nozzle installed at the bottom of the autoclave to extract the low condensate. Then, after cooling to room temperature, it grind | pulverized to the particle size of 1.5 mm or less with the grinder, and it dried at 110 degreeC for 24 hours. The obtained low condensate had a water content of 4100 ppm and an intrinsic viscosity [η] of 0.13 dl / g. Next, this low condensate was put into a shelf type solid phase polymerization apparatus, and after nitrogen substitution, the temperature was raised to 180 ° C. over about 1 hour and 30 minutes. Thereafter, the reaction was performed for 1 hour 30 minutes, and the temperature was lowered to room temperature. The intrinsic viscosity [η] of the obtained polyamide was 0.17 dl / g. After that, in a twin screw extruder with a screw diameter of 30 mm and L / D = 36, melt polymerization is performed at a barrel setting temperature of 330 ° C., a screw rotation speed of 200 rp, and a resin supply speed of 5 kg / h, and a melting point is 264 ° C. and an intrinsic viscosity. A semi-aromatic polyamide resin (c2) having [η] of 1.04 dl / g was prepared.

  (3) Preparation of Aliphatic Polyamide Resin (c3) As the aliphatic polyamide resin (c3), nylon 12 and Rilamid AESNO TL44 manufactured by Arkema Inc. were used.

(4) Preparation of modified ethylene / 1-butene copolymer (PO) 0.63 mg of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride is placed in a glass flask sufficiently substituted with nitrogen, and methylamino is further added. A catalyst solution was obtained by adding 1.57 ml of a toluene solution (Al; 0.13 mmol / liter) of xane and 2.43 ml of toluene.
Next, 912 ml of hexane and 320 ml of 1-butene were introduced into a 2 liter stainless steel autoclave sufficiently purged with nitrogen, and the temperature inside the system was raised to 80 ° C. Subsequently, 0.9 mmol of triisobutylaluminum and 2.0 ml of the catalyst solution prepared above (0.0005 mmol as Zr) were injected into the system with ethylene to initiate the polymerization reaction. By continuously supplying ethylene, the total pressure was kept at 8.0 kg / cm ² -G, and polymerization was carried out at 80 ° C. for 30 minutes.
A small amount of ethanol was introduced into the system to stop the polymerization, and then unreacted ethylene was purged. The obtained solution was poured into a large excess of methanol to precipitate a white solid. The white solid was collected by filtration and dried overnight under reduced pressure to obtain a white solid (ethylene / 1-butene copolymer). The density is 0.865 g / cm ³ , the melt flow rate (190 ° C., 2.16 kg load) measured according to ASTM D1238 is 0.5 g / 10 min, and the 1-butene structural unit content is It was 4 mol%.

  To 100 parts by mass of the obtained ethylene / 1-butene copolymer, 1.0 part by mass of maleic anhydride and 0.04 part by mass of peroxide (Perhexine (registered trademark) 25B, manufactured by NOF Corporation) were mixed. . The obtained mixture was melt graft modified with a single screw extruder set at 230 ° C. to obtain a modified ethylene / 1-butene copolymer (PO) having the following physical properties. The amount of maleic anhydride graft modification was 0.90% by mass. The intrinsic viscosity [η] measured in a 135 ° C. decalin solution was 1.98 dl / g.

(5) Preparation of semi-aromatic polyamide resin compositions (C1) and (C2) The semi-aromatic polyamide resin (c1) or semi-aromatic polyamide resin (c2) and the modified ethylene / 1-butene copolymer ( PO) and an antioxidant (Sumilizer GA-80, manufactured by Sumitomo Chemical Co., Ltd.) were mixed using a tumbler blender, and the cylinder temperature was 290 ° C. in a twin-screw extruder (TEX30α manufactured by Nippon Steel). Then, the raw materials were melted and kneaded, extruded into strands, and cooled in a water bath. Then, the pellet-like composition was obtained by taking up the strand with a pelletizer and cutting it. The mass ratio of the semi-aromatic polyamide resin (c1) or the semi-aromatic polyamide resin (c2) and the modified ethylene / 1-butene copolymer (PO) was 85:15, respectively.
The above-mentioned aliphatic polyamide resin (c3) was used as it was without being mixed with the modified olefin polymer.

[Example 1]
Olefin-based thermoplastic elastomer (A1) at 200 ° C., modified propylene / ethylene copolymer (B1) at 215 ° C., semi-aromatic polyamide resin composition (C1) at 320 ° C., using a molding machine manufactured by Pla Giken Melted separately. Each resin was discharged from a molding machine to form a tube having an outer diameter of 8 mm and an inner diameter of 5.8 mm, and the resin was taken out while cooling.
The thickness of the outer layer (olefin-based thermoplastic elastomer layer) / intermediate layer (adhesive layer (modified propylene / ethylene copolymer layer)) / inner layer (semi-aromatic polyamide resin composition layer) of the obtained laminated structure is: It was 800 μm / 50 μm / 250 μm (total thickness 1100 μm).

[Examples 2 to 5 and Comparative Examples 1 to 6]
Example 1 except that the outer layer, the intermediate layer, and the inner layer were made of the resin or resin composition shown in Table 1, had the thickness shown in Table 1, and the melting temperature was set to 270 ° C. when polyamide C3 was used. In the same manner as above, it was formed into a tube shape having an outer diameter of 8 mm and an inner diameter of 5.8 mm. However, Comparative Examples 1 and 2 could not be formed into a tube shape.
In addition, the polyethylene (PE) of the comparative example 6 used the product made from prime polymer, Neozex 4005M.

[Evaluation]
The peel strength, fuel permeability, bending load just before bending, and workability of the tubular molded bodies (laminated structures) obtained in Examples and Comparative Examples were evaluated by the following methods. The results are shown in Table 1.

(Peel strength)
The tube-shaped molded body was cut into a length of about 200 mm, further cut in half in the longitudinal direction, and the laminated portion at one end was peeled off to obtain a test piece. The obtained test piece was fixed to a Shimadzu autograph (AGS-500B) chuck, peeled at a peeling angle of 180 ° C. and a peeling speed of 300 mm / min, and the peel strength was an average value of 10 mm to 70 mm. It was.

(Fuel permeability)
A pseudo fuel CE10 (toluene / isooctane / ethanol = 45/45/10 vol%) was put into a tube cut into a length of 100 mm. And it was set as the test body by sealing both ends. The test specimen was placed in a temperature lowering device (40 ° C.), the mass of the test specimen before and after the test was measured, and the fuel permeability (g / m ² · day) was evaluated from the mass change.

(Bending load just before bending)
As shown in FIG. 2, a tubular molded body (laminated structure) 100 having a length of 500 mm is attached between two flat plates 11 in a U-shape, and the distance between the flat plates 11 is reduced at a speed of 60 mm per minute. . Then, a bending load (repulsive force) is measured with respect to the tube bending radius (a length of 1/2 of the distance 2R between the U-shaped tube-shaped formed bodies is a bending radius) immediately before the tube-shaped formed body 100 is bent. did.

(Bending workability)
A tube having a length of 500 mm was bent at 90 ° and fixed with a fixture. Then, it hold | maintained for 5 minutes in 125 degreeC oven. Then, it was left for 1 hour at room temperature with the fixture removed. The bending angle of the bent portion of the obtained sample was evaluated based on the following criteria.
A: Bending angle 60 ° or more and 90 ° C or less B: Bending angle 30 ° or more and less than 60 ° C C: Measurement not possible (such as tube deformation) or less than 30 °

As shown in Table 1, it has a laminated structure consisting of an olefinic thermoplastic elastomer layer / adhesive layer (modified propylene / α-olefin copolymer layer) / semi-aromatic polyamide layer, and the density of the adhesive layer is When 0.880 to 0.920 g / cm ³ and the melt elongation of the olefinic thermoplastic elastomer layer is 1 to 100 m / min, the peel strength is 23 N / cm or more, and the fuel permeability is Low, the bending load just before bending was low, and the workability was good (Examples 1 to 5).

  On the other hand, even when an olefinic thermoplastic elastomer layer is used for the outer layer, when the melt elongation is smaller than 1 mm / min (Comparative Examples 1 and 2), the olefinic thermoplastic elastomer layer is cut off during tube drawing. As a result, a laminated structure could not be produced.

  Further, when a modified polyethylene / α-olefin copolymer layer is used for the adhesive layer (Comparative Example 3) or when no adhesive layer is provided (Comparative Example 5), the interlayer adhesion of the laminated structure is performed. Sex did not increase sufficiently. Furthermore, when the inner layer was an aliphatic polyamide layer, the fuel permeability was high (Comparative Example 4). In addition, when the outer layer was a polyethylene layer, not only the peel strength increased, but also the workability decreased (Comparative Example 6).

  The laminated structure of the present invention has low fuel permeability and excellent flexibility and workability. Therefore, it is suitable for various hollow structures such as fuel storage tanks and bottles, fuel transfer tubes and hoses, cooling piping tubes and hoses.

1 Outer layer (olefinic thermoplastic elastomer layer)
2 Intermediate layer (adhesive layer)
3 Inner layer (semi-aromatic polyamide layer)
100 Laminated structure (hollow structure)

Claims (13)

An olefinic thermoplastic elastomer layer (A) containing an olefinic thermoplastic elastomer as an outer layer, an adhesive layer (B) containing a modified propylene polymer as an intermediate layer, and a semiaromatic polyamide layer containing a semiaromatic polyamide as an inner layer A laminated structure for a hollow structure having (C),
The modified propylene polymer contained in the adhesive layer (B) is a polymer obtained by graft-modifying an unsaturated carboxylic acid or a derivative thereof to a propylene homopolymer and / or a propylene / α-olefin copolymer,
The adhesive layer (B) has a density measured according to ASTM D1505 of 0.880 to 0.920 g / cm ³ ,
The olefinic thermoplastic elastomer layer (A) has a melt elongation of 1 to 100 m / min measured by a capillary rheometer under the following conditions.
Laminated structure.
(Measurement conditions in capillary rheometer)
Strand length: 10mm
Orifice hole diameter: 1 mm
Melting temperature: 290 ° C
Crosshead speed: 50mm / min The modified propylene polymer contained in the adhesive layer (B) contains 0.08 to 5% by mass of the structure derived from the unsaturated carboxylic acid or derivative thereof,
The laminated structure according to claim 1. The modified propylene polymer included in the adhesive layer (B) includes a structure derived from maleic anhydride,
The laminated structure according to claim 1 or 2. The innermost layer further has a conductive layer containing a resin and a conductive filler,
The laminated structure as described in any one of Claims 1-3. The semi-aromatic polyamide layer (C) includes a semi-aromatic polyamide resin and a modified olefin polymer obtained by modifying an olefin polymer with a compound containing a hetero atom,
The semi-aromatic polyamide resin has a structural unit derived from terephthalic acid [a] and a structural unit derived from an aliphatic diamine [d] having 4 to 12 carbon atoms,
The amount of the structural unit derived from the terephthalic acid [a] is 40 to 100 mol% based on the total dicarboxylic acid structural unit, and the amount of the structural unit derived from the aliphatic diamine [d] is the total diamine structural unit. With respect to 60 to 100 mol%,
The laminated structure as described in any one of Claims 1-4. The modified olefin polymer contained in the semi-aromatic polyamide layer (C) is a modified ethylene / α-olefin copolymer obtained by graft-modifying an ethylene / α-olefin copolymer with an unsaturated carboxylic acid or a derivative thereof. ,
The laminated structure according to claim 5. The semi-aromatic polyamide layer (C) includes a semi-aromatic polyamide resin and a modified olefin polymer obtained by modifying an olefin polymer with a compound containing a hetero atom,
The semi-aromatic polyamide resin is a structural unit derived from terephthalic acid [a], a structural unit derived from isophthalic acid [b], a structural unit derived from an aliphatic dicarboxylic acid [c] having 4 to 10 carbon atoms, Having a structural unit derived from an aliphatic diamine having 4 to 12 carbon atoms,
35 to 50 mol% of structural units derived from the terephthalic acid [a], 25 to 40 mol% of structural units derived from the isophthalic acid [b], and 15 to 35 structural units derived from the aliphatic dicarboxylic acid [c]. Including mol% (provided that the total of [a], [b] and [c] is 100 mol%),
The molar ratio ([a] / [b]) between the structural unit derived from the terephthalic acid [a] and the structural unit derived from the isophthalic acid [b] is 65/35 to 50/50,
The molar ratio ([c] / [b]) between the structural unit derived from the aliphatic dicarboxylic acid [c] and the structural unit derived from the isophthalic acid [b] is 30/70 to 50/50,
The heat of fusion (ΔH) obtained by differential scanning calorimetry (DSC) of the semi-aromatic polyamide resin is 20 to 40 mJ / mg,
The semi-aromatic polyamide resin has an intrinsic viscosity [η] of 0.7 to 1.6 dl / g.
The laminated structure according to any one of claims 1 to 4. The modified olefin polymer contained in the semi-aromatic polyamide layer (C) is a modified ethylene / α-olefin copolymer obtained by graft-modifying an ethylene / α-olefin copolymer with an unsaturated carboxylic acid or a derivative thereof. ,
The laminated structure according to claim 7. The olefin-based thermoplastic elastomer contained in the olefin-based thermoplastic elastomer layer (A) includes a segment composed of a propylene-based resin and a segment composed of an olefin-based copolymer rubber.
The laminated structure according to any one of claims 1 to 8. The laminate structure according to any one of claims 1 to 9,
Hollow structure. Selected from the group consisting of hoses, tubes,
The hollow structure according to claim 10. A fuel piping tube,
The hollow structure according to claim 10 or 11. A cooling system piping tube,
The hollow structure according to claim 10 or 11.

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