Specification
Title of invention: Laminated tube
Technical field
[0001]
　The present invention relates to a laminated tube.
Background technology
[0002]
　For automobile piping tubes, in response to the problem of rusting due to anti-freezing agents on the road, prevention of global warming, and energy saving in the old days, the main material has changed from metal to resin with excellent rust prevention and lightweight. Are being replaced. Usually, the resin used as a tube for piping includes polyamide-based resin, saturated polyester-based resin, polyolefin-based resin, thermoplastic polyurethane-based resin, etc., but in the case of a single-layer tube using these, heat resistance, The applicable range was limited due to insufficient chemical properties.
[0003]
　Tubes for automobile piping are oxygen-containing gasoline blended with alcohols having a low boiling point such as methanol and ethanol or ethers such as ethyl-t-butyl ether (ETBE) from the viewpoint of saving gasoline consumption and improving performance. Etc. are transferred. Further, from the viewpoint of prevention of environmental pollution, strict exhaust gas regulations are implemented including prevention of leakage into the atmosphere due to diffusion of volatile hydrocarbons etc. through a tube partition for piping. In response to such strict regulations, conventionally used polyamide-based resins, in particular, single-layer tubes using polyamide 11 or polyamide 12 alone, which are excellent in strength, toughness, chemical resistance, flexibility, etc. The barrier property against chemicals is not sufficient, and improvement in the alcohol-containing gasoline barrier property is particularly demanded.
[0004]
　As a method of solving this problem, a resin having a good chemical barrier property, for example, saponified ethylene/vinyl acetate copolymer (EVOH), polymetaxylylene adipamide (polyamide MXD6), polybutylene terephthalate (PBT), polyethylene Naphthalate (PEN), polybutylene naphthalate (PBN), polyphenylene sulfide (PPS), polyvinylidene fluoride (PVDF), ethylene/tetrafluoroethylene copolymer (ETFE), ethylene/chlorotrifluoroethylene copolymer (ECTFE) ), tetrafluoroethylene/hexafluoropropylene copolymer (TFE/HFP, FEP), tetrafluoroethylene/hexafluoropropylene/vinylidene fluoride copolymer (TFE/HFP/VDF, THV), tetrafluoroethylene/hexafluoro Propylene/vinylidene fluoride/perfluoro(alkyl vinyl ether) copolymer (TFE/HFP/VDF/PAVE), tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer (TFE/PAVE, PFA), tetrafluoroethylene/ Hexafluoropropylene/perfluoro(alkyl vinyl ether) copolymer (TFE/HFP/PAVE) and chlorotrifluoroethylene/perfluoro(alkyl vinyl ether)/tetrafluoroethylene copolymer (CTFE/PAVE/TFE, CPT) are arranged Has been proposed (see, for example, Patent Document 1).
[0005]
　Among these, the saponified product of ethylene/vinyl acetate copolymer (EVOH) is very excellent in the chemical solution barrier property, particularly in the permeation prevention property against hydrocarbons. For example, a fuel including an outermost layer made of polyamide 12, an adhesive layer made of modified polyolefin, an outer layer made of polyamide 6, an intermediate layer made of saponified ethylene/vinyl acetate copolymer (EVOH), and an innermost layer made of polyamide 6. Piping has been proposed (see Patent Document 2). Further, at least one selected from the group consisting of the outermost layer of polyamide 12, a polyamide 6/12 copolymer, a polyamide 12/6 copolymer, a polyamide 612, a polyamide 610, a mixture of polyamide 12 and polyamide 6 and a compatibilizer. There has been proposed a laminated composite composed of an adhesive layer made of seed, an intermediate layer made of saponified ethylene/vinyl acetate copolymer (EVOH), and an innermost layer made of polyamide 6 or polyamide 12 (Patent Documents 3 and 4). reference). Similarly, the outermost layer made of polyamide 12, an adhesive layer made of a mixture of polyamide 6, polyamide 12, and a polyamine/polyamide copolymer, an intermediate layer made of saponified ethylene/vinyl acetate copolymer (EVOH), polyamide 6 or polyamide. A laminated composite composed of 12 innermost layers has been proposed (see Patent Document 5). The technique is preferably a polyamide copolymer having a specific composition ratio or a mixture of polyamide 6 and polyamide 12 and a compatibilizer as an adhesive layer interposing both polyamide 12 and a saponified product of ethylene/vinyl acetate copolymer. Have been proposed as having a high interlayer adhesion strength.
[0006]
　On the other hand, in order to simplify the entire laminated tube manufacturing process and reduce costs and management, development of an adhesive layer-less method in which the outer layer material polyamide and saponified ethylene/vinyl acetate copolymer (EVOH) are directly bonded Is also progressing. For example, a multilayer structure composed of inner and outer layers of polyamide 12 and polyamide 6 and a compatibilizer and an intermediate layer of saponified ethylene/vinyl acetate copolymer (EVOH), or polyamide 12 and polyamide 6 as hard segments A laminated composite composed of an outer layer made of a polyetheramide elastomer, an intermediate layer made of a saponified product of ethylene/vinyl acetate copolymer (EVOH), a polyamide 610, a polyamide 612, or an inner layer made of a mixture of polyamide 610 and polyamide 6 is obtained. It has been proposed (see Patent Documents 6 and 7). Furthermore, a layer made of a specific polyamide copolymer composed of hexamethylenediamine, terephthalic acid and an aliphatic dicarboxylic acid having 8 to 20 carbon atoms, and a layer made of a saponified ethylene/vinyl acetate copolymer (EVOH) However, a multilayer structure having sufficient interlayer adhesiveness has also been proposed (see Patent Documents 8 and 9).
Prior art documents
Patent literature
[0007]
Patent Document 1: US Pat. No. 5,554,425 Specification
Patent Document 2: Japanese Patent Laid-Open No. 3-177683
Patent Document 3: Special Table 2003-535717
Patent Document 4: Japanese Patent Laid-Open No. 2003-021276
Patent Document 5: Japanese Patent 2002-210904
Patent Document 6: JP-A-2004-262244
Patent Document 7: JP-A 2008-30483 JP
Patent Document 8: JP-A-2013-514212
JP Patent Document 9: JP-A-2016-172447
Summary of the invention
Problems to be Solved by the Invention
[0008]
　In these laminated tubes, the initial interlayer adhesiveness is sufficient. However, there is still room for improvement in the durability of interlayer adhesion after contact and immersion in fuel for a long time, after heat treatment, and the like. In Patent Document 6, 45% by mass of polyamide 6 and 45% by mass of polyamide 12 are used as inner and outer layer materials, and an acid-modified ethylene/α-olefin copolymer as a compatibilizer and 10% by mass of stabilizers are disclosed in Examples. And the initial interlaminar adhesion is sufficient. However, a tube having the same material as the inner and outer layers and a saponified ethylene/vinyl acetate copolymer (EVOH) as the intermediate layer may be inferior in the resistance (chemical resistance) to calcium chloride and zinc chloride, as shown below. found. Further, in Patent Document 7, in order to improve the elongation at break of an extruded article at a high extrusion speed, a modified polyamide (PA) extrusion molding material modified with a polyamide elastomer is used as an outer layer material, and ethylene/vinyl acetate is used. Although a laminated composite in which a saponified copolymer (EVOH) is directly adhered is disclosed, and although there is a description of resistance to interlaminar peel strength, interlaminar adhesion (after contact/immersion in fuel for a long time or after heat treatment ( No specific technical data is disclosed regarding not only the interlaminar adhesion durability) but also the initial interlaminar adhesion.
Means for solving the problem
[0009]
　In order to solve the above-mentioned problems, the present inventors have made earnest studies and as a result, have a layer containing a specific aliphatic polyamide composition and a layer containing a saponified ethylene/vinyl acetate copolymer, and both layers In the adjacent laminated tube, the aliphatic polyamide composition has a melting point of a specific value or less, and the solubility of the aliphatic polyamide and the aliphatic polyamide having a ratio of the number of methylene groups to the number of amide groups is a specific value or more. By containing an aliphatic polyamide in which the absolute value of the difference in parameter SP value falls within a specific range, and an elastomer polymer containing a constitutional unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, a chemical liquid It has been found that a laminated tube having excellent chemical resistance, interlayer adhesion and durability can be obtained while maintaining various properties such as barrier properties, low temperature impact resistance, and elution resistance of monomers and oligomers.
[0010]
　That is, the present invention is
　a laminated tube of two or more layers including a layer (a) and a layer (b)
　, wherein at least one set of the layer (a) and the layer (b) are arranged adjacent to each other. The
　(a) layer contains the aliphatic polyamide composition (A), and the
　(b) layer contains the ethylene/vinyl acetate copolymer saponified composition (B)
　. (A) includes polyamide (A1), polyamide (A2), and elastomer polymer (A3), and the
　polyamide (A1) has a melting point of 210° C. or lower measured according to ISO 11357-3. The ratio of the number of methylene groups to the number of amide groups is 8.0 or more, and the aliphatic polyamide composition (A) contains 40% by mass or more and 85% by mass or less of the
　polyamide (A2). It is a polyamide other than the polyamide (A1), is contained in the aliphatic polyamide composition (A) in an amount of 10% by mass or more and 30% by mass or less, and the
　elastomer polymer (A3) contains a carboxyl group and/or an acid anhydride. The aliphatic polyamide composition (A) contains a structural unit derived from an unsaturated compound having a physical group, and the aliphatic polyamide composition (A) contains 5% by mass or more and 30% by mass or less of the
　polyamide (A1) and the polyamide (A2). 3.) The absolute value of the difference in the solubility parameter SP value with [] ([(SP value of polyamide (A1))-(SP value of polyamide (A2))]] is 1.8 (MPa) 1/2 or more 4. 5 (MPa) 1/2The following relates to a laminated tube.
[0011]
　A preferred embodiment of the laminated tube is shown below. Plural preferable modes can be combined.
　[1] The polyamide (A1) is polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide 1010), polydecamethylene dodecamide (polyamide 1012), polydodecamethylene dodecamide (polyamide 1212). , Polyundecane amide (polyamide 11), and polydodecane amide (polyamide 12), and at least one homopolymer selected from the group consisting of polydodecane amide (polyamide 12) and/or at least one kind of raw material monomer for forming these homopolymers. Laminated tube which is a copolymer of.
　[2] The polyamide (A2) is polycaproamide (polyamide 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azamide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), And at least one homopolymer selected from the group consisting of polyhexamethylene dodecamide (polyamide 612), and/or at least one copolymer using several raw material monomers forming them, or The polycaproamide (polyamide 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azeramide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), and polyhexamethylene dodecamide (polyamide 612). The main component is a raw material monomer that forms at least one selected from the group consisting of 1012), polydodecamethylene dodecamide (polyamide 1212), polyundecane amide (polyamide 11), and polydodecanamide (polyamide 12), and several raw material monomers forming at least one selected from the group consisting of Laminated tubes that are at least one copolymer.
　[3] The terminal amino group concentration (μeq/g) and terminal carboxyl group concentration (μeq/g) of the polyamide (A1) and the polyamide (A2) per 1 g of the aliphatic polyamide composition (A) are mixed. [A]>[B]+10 where [A] (μeq/g) is the terminal amino group concentration and [B] (μeq/g) is the terminal carboxyl group concentration obtained by multiplying the values ​​obtained by multiplying the mass ratios. Laminated tube.
　[4] A laminated tube in which, in at least one set of the adjacent (a) layer and (b) layer, the (b) layer is arranged adjacent to the inside of the (a) layer.
　[5] A layer (c) is further included, and at least one set of the layer (b) and the layer (c) are arranged adjacent to each other, and the layer (c) contains the polyamide composition (C). The polyamide composition (C) contains a polyamide (C1) and an elastomer polymer (C2), and the polyamide (C1) has a melting point of 210° C. or less measured according to “ISO 11357-3, A polyamide other than the "aliphatic polyamide having a ratio of the number of methylene groups to the number of amide groups of 8.0 or more", and is 70% by mass or more and 95% by mass or more with respect to 100% by mass of the total of the polyamide (C1) and the elastomer polymer (C2). % Or less, the elastomer polymer (C2) contains a constitutional unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, and is composed of a polyamide (C1) and an elastomer polymer (C2). A laminated tube containing 5% by mass or more and 30% by mass or less based on 100% by mass in total.
　[6] The layer (c) is a laminated tube disposed inside the layer (b).
　[7] A layer (d) is further included, the layer (d) contains a semi-aromatic polyamide composition (D), and the semi-aromatic polyamide composition (D) is a semi-aromatic polyamide (D1) and And/or semi-aromatic polyamide (D2), and the semi-aromatic polyamide composition (D) contains 60 mass% or more of the semi-aromatic polyamide (D1) and/or the semi-aromatic polyamide (D2). The semi-aromatic polyamide (D1) contains 50 mol% or more of an aliphatic diamine unit having 4 to 12 carbon atoms, based on all diamine units of the semi-aromatic polyamide (D1). 50 mol% or more of dicarboxylic acid units containing at least one selected from the group consisting of terephthalic acid units, isophthalic acid units, and naphthalenedicarboxylic acid units, based on all dicarboxylic acid units of the group polyamide (D1), The aromatic polyamide (D2) contains 50 mol% or more of a xylylenediamine unit and/or a bis(aminomethyl)naphthalene unit with respect to all the diamine units of the semiaromatic polyamide (D2). A laminated tube containing 50 mol% or more of an aliphatic dicarboxylic acid unit having 4 to 12 carbon atoms with respect to the total dicarboxylic acid unit (D2).
　[8] The semiaromatic polyamide composition (D) contains an elastomer polymer (D3), and the elastomer polymer (D3) is derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group. A laminated tube containing the constituent units.
　[9] The layer (d) is a laminated tube disposed inside the layer (a).
　[10] A laminated tube further comprising a layer (e), wherein the layer (e) contains a fluorine-containing polymer (E) having a functional group reactive with an amino group introduced into a molecular chain.
　[11] The laminated tube according to claim 11, wherein the (e) layer is disposed inside the (a) layer.
　[12] A layer (e) is further included, and at least one set of the layer (d) and the layer (e) are arranged adjacent to each other, and the layer (e) has reactivity with an amino group. A laminated tube containing a fluorine-containing polymer (E) having a functional group introduced into a molecular chain.
　[13] The layer (e) is a laminated tube disposed inside the layer (d).
　[14] A laminated tube in which the innermost layer is a conductive layer containing a thermoplastic resin composition containing a conductive filler.
　[15] A laminated tube produced by coextrusion molding.
　[16] A laminated tube used as a fuel tube.
Effect of the invention
[0012]
　According to the present invention, a laminated tube having excellent chemical resistance, interlayer adhesion, and durability while maintaining various properties such as chemical solution barrier properties, low temperature impact resistance, and elution resistance of monomers and oligomers is provided. can do.
MODE FOR CARRYING OUT THE INVENTION
[0013]
　The laminated tube includes two or more layers including the layer (a) and the layer (b).
　1. The (a) layer of the (a) layer
　laminated tube contains the aliphatic polyamide composition (A).
[0014]
　[Aliphatic Polyamide Composition (A)] The
　aliphatic polyamide composition (A) contains a polyamide (A1), a polyamide (A2), and an elastomer polymer (A3), and the polyamide (A1) is ISO 11357-3. The melting point is 210° C. or less, the ratio of the number of methylene groups to the number of amide groups is 8.0 or more, and the aliphatic polyamide composition (A) contains 40% by mass or more and 85% by mass or more. The polyamide (A2) is contained in an amount of 10% by mass or more and 30% by mass or less in the aliphatic polyamide composition (A), and the elastomer polymer (A3). ) Contains a structural unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, and is contained in the aliphatic polyamide composition (A) in an amount of 5% by mass or more and 30% by mass or less, The absolute value of the difference in the SP value of the solubility parameter between the polyamide (A1) and the polyamide (A2) [|(SP value of polyamide (A1))-(SP value of polyamide (A2))|] is 1.8. (MPa) 1/2 or more and 4.5 (MPa) 1/2 or less (hereinafter sometimes referred to as the aliphatic polyamide composition (A)).
　Further, it is preferable that the aliphatic polyamide composition (A) does not contain a plasticizer from the viewpoint of durability of interlayer adhesion after being contacted and dipped in fuel for a long time and/or after heat treatment for a short time.
[0015]
　[Polyamide (A1)] The
　polyamide (A1) has a melting point (hereinafter sometimes simply referred to as "melting point") measured according to ISO 11357-3 of 210° C. or less and is aliphatic. Containing only a group in the constitutional repeating unit, having an amide bond (—CONH—) in the main chain, and the ratio [CH 2 ]/[NHCO] of the number of methylene groups ([CH 2 ]) to the number of amide groups ([NHCO]) ] (Hereinafter, the ratio of the number of methylene groups to the number of amide groups may be referred to as [CH 2 ]/[NHCO]) is 8.0 or more (hereinafter may be referred to as polyamide (A1)). 　The melting point of polyamide (A1) measured in accordance with ISO 11357-3 is preferably 205° C. or lower, more preferably 200° C. or lower, and further preferably 195° C. or lower. The [CH 2 ]/[NHCO] of the polyamide (A1) is preferably 9.0 or more, more preferably 9.5 or more, and further preferably 10.0 or more. 　According to ISO 11357-3, a differential scanning calorimeter was used to heat the sample to a temperature equal to or higher than the expected melting point, and then the sample was cooled at a rate of 10° C. per minute. The temperature at the peak value of the melting curve measured by cooling to 30° C., leaving it as it is for about 1 minute, and then raising the temperature at a rate of 20° C. per minute was taken as the melting point. 　Number of methylene groups in polyamide (A1) ([CH 2

When the ratio of ]] to the number of amide groups ([NHCO]) is less than the above value, the resulting laminated tube has poor mechanical properties and chemical resistance.
　When the melting point of polyamide (A1) measured according to ISO 11357-3 exceeds the above value, the amide exchange reaction with polyamide (A2) described below does not proceed sufficiently under normal processing temperature, The interlayer adhesion and durability of the obtained laminated tube are poor.
[0016]
　The polyamide (A1) has a melting point of 210° C. or lower measured according to ISO 11357-3, and has a ratio [CH 2 ]/[NHCO] of the number of methylene groups ([CH 2 ]) to the number of amide groups ([NHCO]). ] (Hereinafter, the ratio of the number of methylene groups to the number of amide groups may be referred to as [CH 2 ]/[NHCO]) is 8.0 or more. 　The polyamide (A1) has an melting point of 210° C. or lower measured according to ISO 11357-3, and is an aliphatic having a ratio [CH 2 ]/[NHCO] of methylene groups to 8.0 or more. Polyamide: a single raw material for forming an aliphatic polyamide having a melting point of 210° C. or less measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to 8.0 or more. Polyamide copolymer using only the monomer (constituent repeating unit); melting point measured according to ISO 11357-3 of 210° C. or less, ratio of methylene groups to amide groups [CH 2 ]/[NHCO] Having a ratio of methylene groups to amide groups of at least one raw material monomer (constituting repeating unit) forming an aliphatic polyamide having a ratio of 8.0 or more [CH 2
]/[NHCO] is less than 8.0, a polyamide copolymer using at least one raw material monomer (constituting repeating unit) for forming an aliphatic polyamide; and a melting point measured according to ISO 11357-3. At least one raw material monomer (constituting repeating unit) that forms an aliphatic polyamide having a ratio [CH 2 ]/[NHCO] of more than 210° C. and a ratio [CH 2 ]/[NHCO] of methylene groups to 8.0 or more is used. It is preferably a polymer.
　An example of the preferred polyamide (A1) is a fat having a melting point of 210° C. or lower measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. Group polyamide (A1X) (hereinafter sometimes referred to as polyamide (A1X)), having a melting point of 210° C. or lower measured according to ISO 11357-3, and the ratio of the number of methylene groups to the number of amide groups [CH 2 ]. /[NHCO] is 8.0 or more, a polyamide copolymer (A1XX) using only a raw material monomer (structural repeating unit) forming an aliphatic polyamide (hereinafter sometimes referred to as polyamide (A1XX)). , A raw material unit amount for forming an aliphatic polyamide having a melting point, measured according to ISO 11357-3, of 210° C. or lower and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. At least one component (constituting repeating unit), and the ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] is less than 8.0. A polyamide copolymer (A1Y) using at least one component of a raw material monomer (structural repeating unit) forming an aliphatic polyamide (hereinafter, may be referred to as polyamide (A1Y). And an melting point of more than 210° C. measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. The raw material monomer (structural repeating unit) to be used is separately described as a copolymer (A1Z) using at least one component (hereinafter, sometimes referred to as polyamide (A1Z)).
[0017]
A polyamide (A1X) 　having a melting point of 210° C. or lower measured according to ISO 11357-3 and a ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO] of 8.0 or more is polyundecane amide. (Polyamide 11): [CH 2 ]/[NHCO]=10.0, polydodecanamide (polyamide 12): [CH 2 ]/[NHCO]=11.0, polyhexamethylene hexadecamide (polyamide 616): [CH 2 ]/[NHCO]=10.0, polyhexamethylene octadecamide (polyamide 618):[CH 2 ]/[NHCO]=11.0, polynonamethylene azamide (polyamide 99):[CH 2 ]/[NHCO]=8.0, polynonamethylenedecamide (polyamide 910):[CH 2 ]/[NHCO]=8.5, polynonamethylene dodecamide (polyamide 912):[CH 2 ]/[NHCO ]=9.5, polydecamethylene suberamide (polyamide 108): [CH 2 ]/[NHCO]=8.0, polydecamethylene azeramide (polyamide 109): [CH 2 ]/[NHCO]=8. 5, polydecamethylene sebacamide (polyamide 1010): [CH 2]/[NHCO]=9.0, polydecamethylene dodecamide (polyamide 1012):[CH 2 ]/[NHCO]=10.0, polydodecamethylene azamide (polyamide 129):[CH 2 ]/[NHCO ]=9.5, polydodecamethylene sebacamide (polyamide 1210):[CH 2 ]/[NHCO]=10.0, polydodecamethylene dodecamide (polyamide 1212):[CH 2 ]/[NHCO]=11 .0 etc. are mentioned. These can use 1 type(s) or 2 or more types.
[0018]
　Further, a raw material for forming an aliphatic polyamide , which has a melting point of 210° C. or lower measured according to ISO 11357-3 and a ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO] of 8.0 or more, is used. As the polyamide copolymer (A1XX) using only the monomer (constituent repeating unit), at least one kind of raw material monomer which forms at least one homopolymer of the polyamide (A1X) is used. Copolymers may also be mentioned. These can use 1 type(s) or 2 or more types.
[0019]
　When the polyamide (A1) is a copolymer, the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is such that the number of methylene groups in the homopolymer of the monomers that constitute the constituent repeating units of the copolymer. It can be determined by adding a value obtained by multiplying the ratio [CH 2 ]/[NHCO] with respect to the amide group number by the molar ratio of the constituent repeating units for all constituent repeating units.
　When the polyamide (A1) is a copolymer, its melting point can be obtained as an actual measurement value of the melting point of the copolymer measured according to ISO 11357-3.
[0020]
Raw material monomer forming an aliphatic polyamide having 　a melting point of 210° C. or lower measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. As the polyamide copolymer (A1XX) using only the (structural repeating unit), for example, the ratio of the number of methylene groups to the number of amide groups of the poly(dodecane amide/dodecamethylene dodecamide) copolymer (polyamide 12/1212) [CH 2 ]/[NHCO] is constituted by the fact that the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups of polydodecanamide (polyamide 12) and polydodecamethylene dodecamide (polyamide 1212) is 11.0. The ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 11.0 regardless of the molar ratio of repeating units .
　Moreover, since the melting point of polydodecanamide (polyamide 12) is 178° C. and the melting point of polydodecamethylene dodecamide (polyamide 1212) is 185° C., regardless of the molar ratio of constitutional repeating units, poly(dodecanamide/dodecamide) is used. The melting point of the methylene dodecamide) copolymer (polyamide 12/1212) measured according to ISO 11357-3 is 210° C. or lower.
　Furthermore, the melting point of the poly(dodecane amide/undecane amide) copolymer (polyamide 12/11) and the ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] varies depending on the molar ratio of constitutional repeating units. The ratio [CH 2 ]/[NHCO] of the number of methylene groups of polydodecanamide (polyamide 12) to the number of amide groups is 11.0, and the ratio of the number of methylene groups of polyundecane amide (polyamide 11) to the number of amide groups [CH 2 ]/ Since [NHCO] is 10.0, it can be calculated if the molar ratio of constitutional repeating units is known. Is 80:20 (molar ratio), the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 11.0×0.80+10.0×0.20=10.8. If the molar ratio of undecane amide units increases, the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups decreases, but at least the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 10. It never goes below zero.
　Moreover, since the melting point of polydodecanamide (polyamide 12) is 178° C. and the melting point of polyundecane amide (polyamide 11) is 188° C., the melting point of poly(dodecane amide/undecane amide) copolymer (polyamide 12/11) is The melting point is 210° C. or lower regardless of the molar ratio of constitutional repeating units.
　Thus, like poly(dodecane amide/dodecamethylene dodecamide) copolymer (polyamide 12/1212) and poly(dodecanamide/undecane amide) copolymer (polyamide 12/11), ISO 11357-3 A raw material monomer (constituting repeating unit) that forms an aliphatic polyamide having a melting point of 210° C. or less measured in conformity with, and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. In the polyamide copolymer (A1XX) using only the above, the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 8.0 or more , regardless of the molar ratio of the constitutional repeating units , and ISO 11357-3 And has a melting point of 210° C. or less, which is included in the polyamide (A1) of the present application.
[0021]
　On the other hand, the polyamide (A1) is an aliphatic compound having a melting point of 210° C. or less measured according to ISO 11357-3 and a ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO] of 8.0 or more. A raw material monomer (constituting repeating unit) for forming a polyamide is used as at least one component to form an aliphatic polyamide having a ratio [CH 2 ]/[NHCO] of methylene groups to the number of amide groups of less than 8.0 as described later. It is also possible to copolymerize the raw material monomer (constituent repeating unit) using at least one component, and the obtained polyamide copolymer (A1Y) has a melting point of 210° C. or lower measured according to ISO 11357-3. Therefore, as long as the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 8.0 or more, it is included in the polyamide (A1) of the present application. Examples of the aliphatic polyamide
　having a ratio [CH 2 ]/[NHCO] of methylene groups to the number of amide groups of less than 8.0 include polycaproamide (polyamide 6): [CH 2 ]/[NHCO]=5.0, polyethylene azide. Pamide (polyamide 26): [CH 2 ]/[NHCO]=3.0, polytetramethylene succinamide (polyamide 44): [CH 2 ]/[NHCO]=3.0, polytetramethylene glutamide ( Polyamide 45): [CH 2]/[NHCO]=3.5, polytetramethylene adipamide (polyamide 46):[CH 2 ]/[NHCO]=4.0, polytetramethylene suberamide (polyamide 48):[CH 2 ]/[ NHCO]=5.0, polytetramethylene azeramide (polyamide 49): [CH 2 ]/[NHCO]=5.5, polytetramethylene sebacamide (polyamide 410):[CH 2 ]/[NHCO]= 6.0, polytetramethylene dodecamide (polyamide 412): [CH 2 ]/[NHCO]=7.0, polypentamethylene succinamide (polyamide 54): [CH 2 ]/[NHCO]=3.5 , Polypentamethylene glutamide (polyamide 55): [CH 2 ]/[NHCO]=4.0 , polypentamethylene adipamide (polyamide 56): [CH 2 ]/[NHCO]=4.5, polypenta Methylenesveramide (polyamide 58): [CH 2 ]/[NHCO]=5.5, polypentamethylene azamide (polyamide 59): [CH 2 ]/[NHCO]=6.0, polypentamethylene sebacamide (Polyamide 510): [CH 2]/[NHCO]=6.5, polypentamethylene dodecamide (polyamide 512):[CH 2 ]/[NHCO]=7.5, polyhexamethylene succinamide (polyamide 64):[CH 2 ]/[ NHCO]=4.0, polyhexamethylene glutamide (polyamide 65): [CH 2 ]/[NHCO]=4.5, polyhexamethylene adipamide (polyamide 66): [CH 2 ]/[NHCO]= 5.5, polyhexamethylene suberamide (polyamide 68): [CH 2 ]/[NHCO]=6.0, polyhexamethylene azamide (polyamide 69): [CH 2 ]/[NHCO]=6.5, Polyhexamethylene sebacamide (polyamide 610): [CH 2 ]/[NHCO]=7.0, polynonamethylene adipamide (polyamide 96): [CH 2 ]/[NHCO]=6.5, polynona Methylene suberamide (polyamide 98): [CH 2 ]/[NHCO]=7.5, polydecamethylene glutamide (polyamide 105): [CH 2 ]/[NHCO]=6.5, polydecamethylene adipamide (Polyamide 106): [CH 2]/[NHCO]=7.0, polydodecamethylene glutamide (polyamide 125):[CH 2 ]/[NHCO]=7.5, and the like. Further, as the aliphatic polyamide having a ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups of less than 8.0, several raw material monomers forming the above-mentioned at least one homopolymer were used. At least one copolymer may also be mentioned. These can use 1 type(s) or 2 or more types.
[0022]
Raw material monomer forming an aliphatic polyamide having 　a melting point of 210° C. or less measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. (Constituent repeating unit) as at least one component and at least one raw material monomer (constituent repeating unit) forming an aliphatic polyamide having a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of less than 8.0. As the polyamide copolymer (A1Y) used as the component, for example, the melting point of the poly(dodecanamide/caproamide) copolymer (polyamide 12/6) and the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups are: It depends on the molar ratio of constitutional repeating units. The ratio [CH 2 ]/[NHCO] of the number of methylene groups of polydodecanamide (polyamide 12) to the number of amide groups is 11.0, and the ratio of the number of methylene groups of polycaproamide (polyamide 6) to the number of amide groups [CH 2 ]/ Since [NHCO] is 5.0, it can be calculated if the molar ratio of constitutional repeating units is known, and the ratio of dodecane amide unit/caproamide unit of the poly(dodecane amide/capro amide) copolymer (polyamide 12/6) is 50. The polyamide copolymer having a molar ratio of 0.0:50.0 to 99.5:0.5 has a ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] becomes 8.0 or more. However, in order to distinguish poly(dodecane amide/capro amide) copolymer (polyamide 12/6) and poly dodecane amide (polyamide 12), dodecane amide of poly(dodecane amide/capro amide) copolymer (polyamide 12/6) When the ratio of units/caproamide units is higher than 99.5:0.5 (molar ratio), the ratio of dodecane amide units is treated as polydodecanamide (polyamide 12). Hereinafter, the homopolymer and the copolymer are treated in the same manner.
　Further, the melting point of polydodecanamide (polyamide 12) is 178° C., the melting point of polycaproamide (polyamide 6) is 220° C., and the dodecane amide unit of poly(dodecane amide/capro amide) copolymer (polyamide 12/6) is /The melting point of the polyamide copolymer having a caproamide unit of 4.0:96.0 to 99.5:0.5 (molar ratio), measured according to ISO 11357-3, is 210° C. or lower.
　That is, a polyamide copolymer having a poly(dodecane amide/capro amide) copolymer (polyamide 12/6) having a dodecane amide unit/capro amide unit of 50.0:50.0 to 99.5:0.5 (molar ratio). The combined product has a ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups of 8.0 or more, and a melting point of 210° C. or less measured according to ISO 11357-3. Included.
　As described above, the melting point measured according to ISO 11357-3 is 210° C. or lower, and the ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] is 8.0 or more as a raw material monomer (constituting repeating unit) forming an aliphatic polyamide, and the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 8. The ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups in the polyamide copolymer (A1Y) using at least one raw material monomer (constituting repeating unit) that forms an aliphatic polyamide of less than 0 is Repeat molar ratio and the ratio of the amide groups of the methylene groups of each constituent repeating units of the unit [CH 2 ] can be calculated by the / [NHCO], the ratio of amide groups of the methylene groups [CH 2 ] / [NHCO] 8 Polyamide (A1) of the present application is included as long as it has a melting point of not less than 0.0 and a melting point of 210° C. or less measured according to ISO 11357-3.
[0023]
　The polyamide (A1) is an aliphatic polyamide having a melting point of 210° C. measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. It is also possible to copolymerize the raw material monomer (constituting repeating unit) to be formed by using at least one component, and the obtained polyamide copolymer (A1Z) has a melting point of 210° C. measured according to ISO 11357-3. It is included in the polyamide (A1) of the present application as long as the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 8.0 or more.
[0024]
　Conforming to ISO 11357-3 above the melting point is 210 ° C. as measured, the ratio amide groups methylene groups [CH 2 Examples] / [NHCO] 8.0 or more polyamides, polyhexamethylene dodecamide (polyamide 612 ): [CH 2 ]/[NHCO]=8.0, melting point 218° C., polyhexamethylene tetradecamide (polyamide 614):[CH 2 ]/[NHCO]=9.0, melting point 212° C., etc. .. These can use 1 type(s) or 2 or more types.
[0025]
A raw material monomer that forms an aliphatic polyamide having 　a melting point of more than 210° C. measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more. As the copolymer (A1Z) using at least one component of (structural repeating unit), for example, the melting point and the number of methylene groups of the poly(hexamethylene hexadecamide/hexamethylene tetradecamide) copolymer (polyamide 616/614) The ratio [CH 2 ]/[NHCO] to the number of amide groups varies depending on the molar ratio of constitutional repeating units. The ratio [CH 2 ]/[NHCO] of the number of methylene groups of polyhexamethylene hexadecamide (polyamide 616) to the number of amide groups is 10.0, and the number of methylene groups of polyhexamethylene tetradecamide (polyamide 614) to the number of amide groups is Since the ratio [CH 2 ]/[NHCO] is 9.0, it can be calculated if the molar ratio of constitutional repeating units is known, and a poly(hexamethylene hexadecamide/hexamethylene tetradecamide) copolymer (polyamide 616/614) hexamethylene hexadecamide unit/hexamethylene tetradecamide unit is 30:70 (molar ratio), the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 10.0× 0.30+9.0×0.70=9.3. If the molar ratio of hexamethylene tetradecamide unit increases, the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups decreases, but at least the ratio of the number of methylene groups to the number of amide groups [CH 2 2 ]/[NHCO] never falls below 9.0.
　Further, the melting point of polyhexamethylene hexadecamide (polyamide 616) is 207° C., the melting point of polyhexamethylene tetradecamide (polyamide 614) is 212° C., and poly(hexamethylene hexadecamide/hexamethylene tetradecamide) A polyamide copolymer in which the hexamethylene hexadecamide unit/hexamethylene tetradecamide unit of the copolymer (polyamide 616/614) is 14.0:86.0 to 99.5:0.5 (molar ratio). The melting point measured according to ISO 11357-3 is 210° C. or lower.
　That is, the hexamethylene hexadecamide unit/hexamethylene tetradecamide unit of the poly(hexamethylene hexadecamide/hexamethylene tetradecamide) copolymer (polyamide 616/614) is 14.0:86.0 to 99. In the polyamide copolymer having a ratio of 0.5:0.5 (molar ratio), the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups was 8.0 or more, which was measured according to ISO 11357-3. It has a melting point of 210° C. or lower and is included in the polyamide (A1) of the present application.
[0026]
　Further, a starting material for forming an aliphatic polyamide having a melting point of more than 210° C. measured according to ISO 11357-3 and a ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO] of 8.0 or more. As a copolymer (A1Z) using at least one component of a monomer (structural repeating unit), for example, the melting point and the number of methylene groups of a poly(hexamethylene dodecamide/hexamethylene tetradecamide) copolymer (polyamide 612/614) The ratio [CH 2 ]/[NHCO] to the number of amide groups depends on the molar ratio of the constituent repeating units. The ratio [CH 2 ]/[NHCO] of the number of methylene groups of polyhexamethylene dodecamide (polyamide 612) to the number of amide groups was 8.0, and the ratio of the number of methylene groups of polyhexamethylene tetradecamide (polyamide 614) to the number of amide groups. Since [CH 2 ]/[NHCO] is 9.0, it can be calculated by knowing the molar ratio of constitutional repeating units, and poly(hexamethylene dodecamide/hexamethylene tetradecamide) copolymer (polyamide 612/ In the case of a polyamide copolymer having a hexamethylene dodecamide unit/hexamethylene tetradecamide unit of 614) of 70.0:30.0 (molar ratio), the ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO ] Is 8.0×0.70+9.0×0.30=8.3. If the molar ratio of hexamethylene dodecamide units increases, the ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] decreases, but the ratio [CH 2 ]/[NHCO] of at least the number of methylene groups to the number of amide groups does not fall below 8.0.
　Further, the melting point of polyhexamethylene dodecamide (polyamide 612) is 218° C., the melting point of polyhexamethylene tetradecamide (polyamide 614) is 212° C., and poly(hexamethylene dodecamide/hexamethylene tetradecamide) co-weight Melting point of the polyamide (polyamide 612/614) having a hexamethylene dodecamide unit/hexamethylene tetradecamide unit of 70.0:30.0 (molar ratio), measured according to ISO 11357-3 Is 206°C. The hexamethylene dodecamide unit/hexamethylene tetradecamide unit of the poly(hexamethylene dodecamide/hexamethylene tetradecamide) copolymer (polyamide 612/614) is 80.0:20.0 (molar ratio). The melting point of a polyamide copolymer measured according to ISO 11357-3 is 209°C.
　Thus, an aliphatic polyamide having a melting point of more than 210° C. measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more is formed. A polyamide copolymer (A1Z) using at least one component of a raw material monomer (constituent repeating unit) has a ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups regardless of the molar ratio of the constituent repeating units . Is 8.0 or more, and the melting point measured according to ISO 11357-3 is 210° C. or less, it is included in the polyamide (A1) of the present application.
[0027]
　Among them, the polyamide (A1) is a polyundecane amide (polyundecaneamide) from the viewpoints of sufficiently securing various physical properties such as mechanical properties, heat resistance, and chemical resistance of the obtained laminated tube, and from the viewpoint of economical efficiency and availability. Polyamide 11), polydodecanamide (polyamide 12), polynonamethylene azamide (polyamide 99), polynonamethylene decamide (polyamide 910), polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide) 1010), polydecamethylene dodecamide (polyamide 1012), and at least one homopolymer selected from the group consisting of polydodecamethylene dodecamide (polyamide 1212), and/or several raw materials forming these. At least one copolymer is more preferable, and polyundecane amide (polyamide 11), polydodecanamide (polyamide 12), polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide 1010), poly At least one homopolymer selected from the group consisting of decamethylene dodecamide (polyamide 1012) and polydodecamethylene dodecamide (polyamide 1212), and/or using at least several raw material monomers forming them. One copolymer is more preferred.
　Further, from the viewpoint of elution resistance of the monomers and oligomers, homopolymers of polydecamethylenedecamide (polyamide 1010) and/or polydecamethylenedodecamide (polyamide 1012), and/or raw material monomers for forming these The copolymer using is particularly preferable.
[0028]
　[Polyamide (A2)] The
　polyamide (A2) is a polyamide other than the polyamide (A1), has a amide bond (-CONH-) in the main chain, and is a raw material monomer (structuring repeating unit) that forms the polyamide. ) Is obtained by polymerizing or copolymerizing an aliphatic lactam, an aliphatic aminocarboxylic acid, or an aliphatic diamine and an aliphatic dicarboxylic acid (hereinafter, sometimes referred to as polyamide (A2)).
　The absolute value of the difference between the solubility parameter SP values ​​of the polyamide (A1) and the polyamide (A2) [|(SP value of polyamide (A1))-(SP value of polyamide (A2))|] is 1.8 ( MPa) 1/2 or more and 4.5 (MPa) 1/2 or less, preferably 2.0 (MPa) 1/2 or more and 4.3 (MPa) 1/2 or less, and preferably 2.2 (MPa). ) 1/2 or more and 4.1 (MPa) 1/2 or less is more preferable. When the absolute value of the difference in the solubility parameter SP value between the polyamide (A1) and the polyamide (A2) is less than the above value, the interlayer adhesion of the resulting laminated tube and its durability are poor, while the above value If it exceeds, the mechanical properties and chemical resistance of the obtained laminated tube will be poor.
　The solubility parameter SP value is a value obtained from the Fedors equation shown below and is a value represented by the square root of the molecular cohesive energy density, and the unit is (MPa) 1/2, And the value at 25° C. (hereinafter, the solubility parameter may be referred to as SP value).
δ=[ΔEv/ΔV] 1/2 =[ΣΔe i /ΣΔv i ] 1/2
δ: solubility parameter SP value
ΔEv: cohesive energy
ΔV: molar molecular volume
Δe i : molar aggregation of atom or atomic group of i component Energy
Δv i : Molar molecular volume of atom or atomic group of i component
　Here, ΔEv and ΔV are represented by ΔEv=ΣΔe i and ΔV=ΣΔv i , respectively , and e i and v i are POLYMER ENGINEERING AND SCIENCE (1974) Annual publication, Vol. 14, No. 2, pp. 147-154). Hereinafter, the SP value described in this specification is a value in which the unit is (MPa) 1/2 .
　The solubility parameter SP value of each polyamide (A1) given as a preferable example is polyundecane amide (polyamide 11, SP value: 22.9 (MPa) 1/2 ), polydodecane amide (polyamide 12, SP). Value: 22.5 (MPa) 1/2 ), polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ), polynonamethylene decamide (polyamide 910, SP value: 23. 8 (MPa) 1/2 ), polynonamethylene dodecamide (polyamide 912, SP value: 23.2 (MPa) 1/2 ), polydecamethylene sebacamide (polyamide 1010, SP value: 23.5 (MPa) ) 1/2 ), polydecamethylene dodecamide (polyamide 1012, SP value: 22.9 (MPa) 1/2 ), polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1/2 ) ).
[0029]
　The polyamide (A2) is a polyamide other than the polyamide (A1), and the absolute value of the difference in the solubility parameter SP value from the polyamide (A1) is 1.8 (MPa) 1/2 or more and 4.5 (MPa ). ) It may be 1/2 or less, and is appropriately selected so as to satisfy this.
　The polyamide (A2) is an aliphatic polyamide having a melting point of more than 210° C. measured according to ISO 11357-3 and a ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO] of 8.0 or more; Aliphatic polyamide having a melting point of more than 210° C., measured according to ISO 11357-3, and a ratio of methylene groups to amide groups [CH 2 ]/[NHCO] of less than 8.0; and according to ISO 11357-3 It is preferable that the aliphatic polyamide has a melting point of 210° C. or lower measured by the above method and has a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of less than 8.0. An example of a preferred polyamide (A2) is an aliphatic polyamide (A2X) in which the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is less than 8.0 regardless of the melting point measured according to ISO 11357-3. ) (Hereinafter sometimes referred to as polyamide (A2X)) and having a melting point of more than 210° C. measured according to ISO 11357-3, and the ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] is 8.0 or more and aliphatic polyamide (A2Y) (hereinafter sometimes referred to as polyamide (A2Y)) will be described separately.
[0030]
　Despite the melting point measured according to ISO 11357-3, the aliphatic polyamide (A2X) having a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of less than 8.0 is polycaproamide (polyamide). 6, SP value: 26.9 (MPa) 1/2 ), polytetramethylene glutamide (polyamide 45, SP value: 29.2 (MPa) 1/2 ), polytetramethylene adipamide (polyamide 46, SP) Value: 28.3 (MPa) 1/2 ), polytetramethylene sveramide (polyamide 48, SP value: 26.9 (MPa) 1/2 ), polytetramethylene azeramide (polyamide 49, SP value: 26. 3 (MPa) 1/2 ), polytetramethylene sebacamide (polyamide 410, SP value: 25.7 (MPa) 1/2 ), polytetramethylene dodecamide (polyamide 412, SP value: 24.9 (MPa) ) 1/2 ), polypentamethylene succinamide (polyamide 54, SP value: 29.2 (MPa) 1/2 ), polypentamethylene glutamide (polyamide 55, SP value: 28.3 (MPa) 1 / 2 ), polypentamethylene adipamide (polyamide 56, SP value: 27.5 (MPa) 1/2), Poly pentamethylene suberamide (polyamide 58, SP value: 26.3 (MPa) 1/2 ), poly pentamethylene azelamide (polyamide 59, SP value: 25.7 (MPa) 1/2 ), Poripenta Methylene sebacamide (polyamide 510, SP value: 25.3 (MPa) 1/2 ), polyhexamethylene succinamide (polyamide 64, SP value: 28.3 (MPa) 1/2 ), polyhexamethylene glutami (Polyamide 65, SP value: 27.5 (MPa) 1/2 ), polyhexamethylene adipamide (polyamide 66, SP value: 26.9 (MPa) 1/2 ), polyhexamethylene suberamide (polyamide) 68, SP value: 25.7 (MPa) 1/2 ), polyhexamethylene azeramide (polyamide 69, SP value: 25.3 (MPa) 1/2 ), polyhexamethylene sebacamide (polyamide 610, SP) Value: 24.9 (MPa) 1/2 ), polynonamethylene adipamide (polyamide 96, SP value: 25.3 (MPa) 1/2 ), polydecamethylene glutamide (polyamide 105, SP value: 25) .3 (MPa) 1/2), polydecamethylene adipamide (polyamide 106, SP value: 24.9 (MPa) 1/2 ), polypentamethylene dodecamide (polyamide 512, SP value: 24.5 (MPa) 1/2 ), poly Dodecamethylene glutamide (polyamide 125, SP value: 24.5 (MPa) 1/2 ) and the like can be mentioned. The polyamide (A2X) also includes at least one copolymer using several raw material monomers forming the above-mentioned at least one homopolymer. Further, as long as the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is less than 8.0, a raw material monomer forming at least one homopolymer of the polyamide (A1), and/or At least one copolymer using several raw material monomers forming at least one homopolymer of polyamide (A2Y) described later is also included. These can use 1 type(s) or 2 or more types.
[0031]
　Among the polyamides (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value) having the lowest solubility parameter SP value. : 22.5 (MPa) 1/2 ) is selected, polypentamethylene dodecamide (polyamide 512, SP value: 24.5 (MPa) having the lowest solubility parameter SP value among the above polyamides (A2X). ) 1/2 ) and polydodecamethylene glutamide (polyamide 125, SP value: 24.5 (MPa) 1/2 ), the absolute value of the difference in solubility parameter SP value is 2.0 (MPa) 1/2. Therefore, it is within the specified range of the present application. Therefore, as the polyamide (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1 / 2 ), and (as A2X), poly pentamethylene dodecamide (polyamide 512, SP value: 24.5 (MPa) polyamide 1/2 ) and / or poly-dodecamethylene glutamide (polyamide 125, SP value: 24. The combination of 5) is within the specified range of the present application.
　On the other hand, when polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value among the polyamide (A1 ) is selected, the polyamide (A2X Among these, polypentamethylene dodecamide (polyamide 512, SP value: 24.5 (MPa) 1/2 ) and polydodecamethylene glutamide (polyamide 125, SP value: 24.5) having the lowest solubility parameter SP value. The absolute value of the difference between the solubility parameter SP value and (MPa) 1/2 ) is 0.4 (MPa) 1/2 , which is outside the specified range of the present application. Therefore, as the polyamide (A1), polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) and as the polyamide (A2X), polypentamethylene dodecamide (polyamide 512, SP value: The combination of 24.5 (MPa) 1/2 ) and/or polydodecamethylene glutamide (polyamide 125, SP value: 24.5 (MPa) 1/2 ) is out of the specified range of the present application, and polyamide (A1) When polynonamethylene azeramide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) is selected as, the absolute value of the difference in the solubility parameter SP value is 1.8 (MPa) 1/2In order to attain the above, it is necessary to select a polyamide (A2X) having a solubility parameter SP value of 25.9 (MPa) 1/2 or more.
　In addition, polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212) having the lowest solubility parameter SP value among the polyamides (A1) . When SP value: 22.5 (MPa) 1/2 ) is selected, polytetramethylene adipamide (polyamide 46, SP value: 28.28) having the highest solubility parameter SP value among the above polyamides (A2X). 3 (MPa) 1/2 ) and polyhexamethylene succinamide (polyamide 64, SP value: 28.3 (MPa) 1/2 ) the absolute value of the difference in solubility parameter SP value is 5.8 (MPa). ) 1/2 , which is outside the range specified in the present application. Therefore, as the polyamide (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1 /2 ) and polyamide (A2X) as polytetramethylene adipamide (polyamide 46, SP value: 28.3 (MPa) 1/2) And/or polyhexamethylene succinamide (polyamide 64, SP value: 28.3 (MPa) 1/2 ) is outside the specified range of the present application, and polydodecanamide (polyamide 12) is used as the polyamide (A1). , SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1/2 ), the solubility parameter SP value In order for the absolute value of the difference to be 4.5 (MPa) 1/2 or less, it is necessary to select a polyamide (A2X) having a solubility parameter SP value of 27.0 (MPa) 1/2 or less.
　On the other hand, when polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value among the polyamide (A1 ) is selected, the polyamide (A2X Among them, polytetramethylene adipamide (polyamide 46, SP value: 28.3 (MPa) 1/2 ) and polyhexamethylene succinamide (polyamide 64, SP value: 28) having the highest solubility parameter SP value. .3 (MPa) 1/2 absolute value of the difference between the solubility parameter SP value of) the 4.2 (MPa) 1/2Therefore, it is within the specified range of the present application. Therefore, as the polyamide (A1), polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ), and as the polyamide (A2X), polytetramethylene adipamide (polyamide 46, SP value) : 28.3 (MPa) 1/2 ) and/or a combination of polyhexamethylene succinamide (polyamide 64, SP value: 28.3 (MPa) 1/2 ) is within the specified range of the present application.
[0032]
Polyamide (A2Y) 　having a melting point of more than 210° C. measured according to ISO 11357-3 and a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8.0 or more is polyhexamethylene. Dodecamide (polyamide 612, SP value: 24.1 (MPa) 1/2 ), polyhexamethylene tetradecamide (polyamide 614, SP value: 23.5 (MPa) 1/2 ), polyoctamethylene dodecamide ( Polyamide 812, SP value: 23.5 (MPa) 1/2 ), polydodecamethylene adipamide (polyamide 126, SP value: 24.1 (MPa) 1/2 ), polydodecamethylene suberamide (polyamide 128, SP value: 23.5 (MPa) 1/2 ), polytetradecamethylene adipamide (polyamide 146, SP value: 23.5 (MPa) 1/2 ) and the like. The polyamide (A2Y) is a raw material monomer forming at least one homopolymer of the polyamide (A2Y), and/or the polyamide, as long as the melting point measured according to ISO 11357-3 exceeds 210° C. At least one copolymer using several raw material monomers forming at least one homopolymer of (A2X) is also included. These can use 1 type(s) or 2 or more types.
[0033]
　Among the polyamides (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value) having the lowest solubility parameter SP value. : 22.5 (MPa) 1/2 ) is selected, polyhexamethylene tetradecamide (polyamide 614, SP value: 23.5() having the lowest solubility parameter SP value among the polyamides (A2Y). MPa) 1/2 ), polyoctamethylene dodecamide (polyamide 812, SP value: 23.5 (MPa) 1/2 ), polydodecamethylene suberamide (polyamide 128, SP value: 23.5 (MPa) 1 / 2 ) and polytetradecamethylene adipamide (polyamide 146, SP value: 23.5 (MPa) 1/2 ), the absolute value of the difference in the solubility parameter SP value is 1.0 (MPa) 1/2 Therefore, it is out of the specified range of the present application.
　On the other hand, when polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value among the polyamide (A1 ) is selected, the polyamide (A2Y) is selected. Among these, polyhexamethylenetetradecamide having the lowest solubility parameter SP value (polyamide 614, SP value: 23.5 (MPa) 1/2), polyoctamethylene dodecamide (polyamide 812, SP value: 23.5 (MPa) 1/2 ), polydodecamethylene suberamide (polyamide 128, SP value: 23.5 (MPa) 1/2 ), and poly The absolute value of the difference in the solubility parameter SP value from tetradecamethylene adipamide (polyamide 146, SP value: 23.5 (MPa) 1/2 ) is 0.8 (MPa) 1/2 , which is defined in the present application. It is out of range.
　In addition, polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212) having the lowest solubility parameter SP value among the above polyamides (A1) . When SP value: 22.5 (MPa) 1/2 ) is selected, polyhexamethylene dodecamide (polyamide 612, SP value: 24.1) having the highest solubility parameter SP value among the polyamides (A2Y). (MPa) 1/2 ) and polydodecamethylene adipamide (polyamide 126, SP value: 24.1 (MPa) 1/2 ) have an absolute value of the solubility parameter SP value of 1.6 (MPa). It becomes 1/2 , which is out of the specified range of the present application.
　On the other hand, when polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value among the polyamide (A1 ) is selected, the polyamide (A2Y) is selected. Among them, polyhexamethylene dodecamide (polyamide 612, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value and polydodecamethylene adipamide (polyamide 126, SP value: 24. The absolute value of the difference in the solubility parameter SP value from 1 (MPa) 1/2 ) is 0 (MPa) 1/2 , which is outside the specified range of the present application.
[0034]
　Sufficient physical properties such as availability, economy, compatibility with the above-mentioned polyamide (A1), mechanical properties of the obtained laminated tube, chemical resistance, flexibility and the like, and ethylene/vinyl acetate described later From the viewpoint of obtaining sufficient interlayer adhesion with the saponified copolymer composition (B) and its durability, the polyamide (A2) has a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8. An aliphatic polyamide (A2X) of less than 0 or a melting point of more than 210° C. measured according to ISO 11357-3, or a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of 8. 3. The absolute value of the difference in the solubility parameter SP value from the polyamide (A1) from at least one selected from the group consisting of 0 or more aliphatic polyamides (A2Y) is 1.8 (MPa) 1/2 or more and 4. 5 (MPa) 1/2It is preferable to select appropriately so as to satisfy the following. Specifically, polycaproamide (polyamide 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azeramide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), and polyhexamethylene dodeca At least one homopolymer selected from the group consisting of amides (polyamide 612), and/or at least one copolymer using several raw material monomers forming them, or polycaproamide (polyamide) 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azelamide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), and polyhexamethylene dodecamide (polyamide 612) As a main component, a raw material monomer forming at least one of the following: polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide 1010), polydecamethylene dodecamide (polyamide 1012), polydodecamethylene At least one type of copolymerization using several raw material monomers forming at least one selected from the group consisting of dodecamide (polyamide 1212), polyundecane amide (polyamide 11), and polydodecanamide (polyamide 12) It is more preferable that they are united.
　Among these, polycaproamide (polyamide 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azamide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), polyhexamethylene dodecamide ( Polyamide 612), poly(caproamide/hexamethylene adipamide) copolymer (polyamide 6/66), poly(caproamide/hexamethylene azamide) copolymer (polyamide 6/69), poly(caproamide/hexamethylene sesame) Bacamide) copolymer (polyamide 6/610), poly(caproamide/hexamethylene dodecamide) copolymer (polyamide 6/612), poly(caproamide/dodecane amide) copolymer (polyamide 6/12), poly (Caproamide/hexamethylene adipamide/hexamethylene sebacamide) copolymer (polyamide 6/66/610), poly(caproamide/hexamethylene adipamide/hexamethylene dodecamide) copolymer (polyamide 6/66 /612), poly(caproamide/hexamethylene adipamide/dodecanamide) copolymer (polyamide 6/66/12), poly(caproamide/hexamethylene sebacamide/dodecanamide) copolymer (polyamide 6/610) /12), poly(caproamide/hexamethylene dodecamide/dodecane amide) copolymer (polyamide 6/612/12), and mixtures thereof are more preferable, and the ratio of the number of methylene groups to the number of amide groups [CH 2]/[NHCO] is an aliphatic polyamide of less than 8.0, and is polycaproamide (polyamide 6), polyhexamethylene sebacamide (polyamide 610), poly(caproamide/hexamethylene adipamide) copolymer (Polyamide 6/66), poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610), poly(caproamide/hexamethylene dodecamide) copolymer (polyamide 6/612), poly(caproamide/ Dodecane amide) copolymer (polyamide 6/12), poly(caproamide/hexamethylene adipamide/hexamethylene sebacamide) copolymer (polyamide 6/66/610), poly(caproamide/hexamethylene adipamide) /Hexamethylene dodecamide) copolymer (polyamide 6/66/612), poly(caproamide/hexamethylene adipamide/dodecane amide) copolymer (polyamide 6/66/12), and mixtures thereof are particularly preferred. ..
[0035]
　For example, the solubility parameter SP value of the poly(caproamide/hexamethylene adipamide) copolymer (polyamide 6/66) is the solubility of polycaproamide (polyamide 6) and polyhexamethylene adipamide (polyamide 66). Since the parameter SP value is 26.9 (MPa) 1/2 , the solubility parameter SP value is 26.9 (MPa) 1/2 regardless of the molar ratio of the constitutional repeating units . Among the polyamides (A1), when polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value is selected, poly(caproamide/hexamethylene) is selected. Since the SP value is 26.9 (MPa) 1/2 regardless of the molar ratio of the constitutional repeating units of the (adipamide) copolymer (polyamide 6/66), the absolute difference between the solubility parameter SP values ​​is absolute. The value is 2.8 (MPa) 1/2 , which is within the specified range of the present application. Therefore, as the polyamide (A1), polynonamethylene azeramide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) and as the polyamide (A2), poly(caproamide/hexamethylene adipamide) copolymerization The combination of the combination (polyamide 6/66, SP value: 26.9 (MPa) 1/2 ) is within the specified range of the present application.
　On the other hand, polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212) having the lowest solubility parameter SP value among the polyamides (A1) . When the SP value: 22.5 (MPa) 1/2 ) is selected, the SP is changed regardless of the molar ratio of the constitutional repeating units of the poly(caproamide/hexamethylene adipamide) copolymer (polyamide 6/66). Since the value is 26.9 (MPa) 1/2 , the absolute value of the difference in the solubility parameter SP value is 4.4 (MPa) 1/2 , which is within the specified range of the present application. Therefore, as the polyamide (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1 /2 ) and a combination of a poly(caproamide/hexamethylene adipamide) copolymer (polyamide 6/66, SP value: 26.9 (MPa) 1/2 ) as the polyamide (A2) are within the specified range of the present application. It is within.
　The ratio of the number of methylene groups to the number of amide groups in the poly(caproamide/hexamethylene adipamide) copolymer (polyamide 6/66) [CH 2]/[NHCO] is 5.0 because the ratio [CH 2 ]/[NHCO] of the number of methylene groups of polycaproamide (polyamide 6) and polyxamethylene adipamide (polyamide 66) to the number of amide groups is 5.0. The ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 5.0 regardless of the molar ratio of the structural repeating units . That is, an aliphatic polyamide having a ratio [CH 2 ]/[NHCO] of methylene groups to amide groups of less than 8.0 , such as a poly(caproamide/hexamethylene adipamide) copolymer (polyamide 6/66), is used. The polyamide copolymer using only the raw material monomer (constituent repeating unit) to be formed has a ratio [CH 2 ]/[NHCO] of methylene groups to the number of amide groups of less than 8.0 regardless of the molar ratio of constituent repeating units. Becomes
[0036]
　For example, the solubility parameter SP value of a poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610) varies depending on the molar ratio of constitutional repeating units. The solubility parameter SP value of polycaproamide (polyamide 6) is 26.9 (MPa) 1/2 , and the solubility parameter SP value of polyhexamethylene sebacamide (polyamide 610) is 24.9 (MPa) 1. Since it is /2 , it can be calculated if the molar ratio of constitutional repeating units is known, and the caproamide unit/hexamethylene sebacamide unit of the poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610) is The solubility parameter SP value of the polyamide copolymer, which is 0.5:99.5 to 99.5:0.5 (molar ratio), is 24.9 (MPa) 1/2 or more and 26.9 (MPa) 1. /2 or less.
　With respect to this poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610), polynonamethylene azeramide (polyamide 99,SP) having the highest solubility parameter SP value among the above polyamides (A1). When the value: 24.1 (MPa) 1/2 ) is selected, the absolute value of the difference in the solubility parameter SP values ​​is 0.8 (MPa) 1/2 or more and 2.8 (MPa) 1/2 or less. Becomes Absolute value of difference in solubility parameter SP value is 1.8 (MPa) 1/2In order to satisfy the above requirement of 4.5 (MPa) 1/2 or less, the caproamide unit/hexamethylene sebacamide unit of the poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610) is 50.0. A polyamide copolymer having a molar ratio of 50.0 to 99.5:0.5 is selected. Therefore, as the polyamide (A1), polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) and as the polyamide (A2), a poly(caproamide/hexamethylene sebacamide) copolymer The combination of polyamide copolymers in which (polyamide 6/610) has a caproamide unit/hexamethylene sebacamide unit of 50.0:50.0 to 99.5:0.5 (molar ratio) is within the specified range of the present application. Is.
　On the other hand, with respect to this poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610), polydodecanamide (polyamide 12, SP) having the lowest solubility parameter SP value among the above polyamides (A1). Value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1/2 ) the difference in solubility parameter SP values. Absolute value of 2.4 (MPa) 1/2 or more and 4.4 (MPa) 1/2The following is obtained: poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6) in which the caproamide unit/hexamethylene sebacamide unit is 0.5:99.5 to 99.5:0.5 (molar ratio). /610), the absolute value of the difference between the solubility parameter SP values satisfies 1.8 (MPa) 1/2 or more and 4.5 (MPa) 1/2 or less. Therefore, as the polyamide (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1 /2 ), and as the polyamide (A2), the caproamide unit/hexamethylene sebacamide unit of the poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610) is 0.5:99.5 to 99. Combinations of polyamide copolymers of 0.5:0.5 (molar ratio) are within the specified range of the present application.
　The ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups of the poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610) varies depending on the molar ratio of the constitutional repeating units. The ratio [CH 2 ]/[NHCO] of the number of methylene groups of polycaproamide (polyamide 6) to the number of amide groups is 5.0, and the ratio of the number of methylene groups of polyhexamethylene sebacamide (polyamide 610) to the number of amide groups [CH Two]/[NHCO] is 7.0 and can be calculated if the molar ratio of the constitutional repeating units is known, and the caproamide unit of the poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610)/ When the hexamethylene sebacamide unit is 80:20 (molar ratio), the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is 5.0×0.80+7.0×0.20=5. It becomes 4. As the molar ratio of hexamethylene sebacamide units increases, the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups increases, but at least the ratio of the number of methylene groups to the number of amide groups [CH 2 ]/[NHCO] Will never exceed 8.0. That is, an aliphatic polyamide in which the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is less than 8.0 , such as a poly(caproamide/hexamethylene sebacamide) copolymer (polyamide 6/610), is used. The polyamide copolymer using only the raw material monomer (constituent repeating unit) to be formed has a ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups of less than 8.0 regardless of the molar ratio of the constituent repeating units. Becomes
[0037]
　The solubility parameter SP value of the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) varies depending on the molar ratio of constitutional repeating units. The solubility parameter SP value of polycaproamide (polyamide 6) is 26.9 (MPa) 1/2 , and the solubility parameter SP value of polydodecanamide (polyamide 12) is 22.5 (MPa) 1/2 . Therefore, it can be calculated if the molar ratio of constitutional repeating units is known, and the caproamide unit/dodecane amide unit of the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) is 0.5:99.5 to 99. The solubility parameter SP value of the polyamide copolymer of 0.5:0.5 (molar ratio) is 22.5 (MPa) 1/2 or more and 26.9 (MPa) 1/2 or less.
　With respect to this poly(caproamide/dodecane amide) copolymer (polyamide 6/12), polynonamethylene azeramide (polyamide 99, SP value: 24) having the highest solubility parameter SP value among the above polyamides (A1). . (1 MPa) 1/2 ) is selected, the absolute value of the difference between the solubility parameter SP values ​​is 0 (MPa) 1/2 or more and 2.8 (MPa) 1/2 or less. Absolute value of difference in solubility parameter SP value is 1.8 (MPa) 1/2 or more 4.5 (MPa) 1/2In order to satisfy the following, the caproamide unit/dodecane amide unit of the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) is 77.28:22.72 to 99.5:0.5 (molar ratio). A polyamide copolymer is selected. Therefore, as the polyamide (A1), polynonamethylene azamide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) and as the polyamide (A2), a poly(caproamide/dodecane amide) copolymer (polyamide 6) The combination of the polyamide copolymer in which the caproamide unit/dodecanamide unit of (12) is 77.28:22.72 to 99.5:0.5 (molar ratio) is within the range specified in the present application.
　On the other hand, with respect to this poly(caproamide/dodecane amide) copolymer (polyamide 6/12), the polydodecanamide (polyamide 12, SP value: 22) having the lowest solubility parameter SP value among the above polyamides (A1). .5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1/2 ), the absolute value of the difference in the solubility parameter SP values. Is 0 (MPa) 1/2 or more and 4.4 (MPa) 1/2 or less. Absolute value of difference in solubility parameter SP value is 1.8 (MPa) 1/2 or more 4.5 (MPa) 1/2In order to satisfy the following, the caproamide unit/dodecane amide unit of the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) is 40.9:50.1 to 99.5:0.5 (molar ratio). A polyamide copolymer is selected. Therefore, as the polyamide (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value: 22.5 (MPa) 1 /2 ), and as the polyamide (A2), the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) has a caproamide unit/dodecane amide unit of 40.9:50.1 to 99.5:0.5. The combination of polyamide copolymers (molar ratio) is within the specified range of the present application.
　The ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups in the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) varies depending on the molar ratio of the structural repeating units. The ratio [CH 2 ]/[NHCO] of the number of methylene groups of polycaproamide (polyamide 6) to the number of amide groups is 5.0, and the ratio of the number of methylene groups of polydodecanamide (polyamide 12) to the number of amide groups [CH 2]/[NHCO] is 11.0, which can be calculated by knowing the molar ratio of the constitutional repeating units. Is 50.1:49.9 to 99.5:0.5 (molar ratio), the ratio [CH 2 ]/[NHCO] of the number of methylene groups to the number of amide groups is less than 8.0. , Polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP) having the lowest solubility parameter SP value among the above polyamides (A1) When the value: 22.5 (MPa) 1/2 ) is selected, as the polyamide (A2), the caproamide unit/dodecane amide unit of the poly(caproamide/dodecane amide) copolymer (polyamide 6/12) is 50. A polyamide copolymer having a molar ratio of 1:49.9 to 99.5:0.5 is preferable.
[0038]
　When the polyamide (A2) is a mixture of two or more kinds, the SP value is calculated by multiplying the SP value of each polyamide (A2) by the mixing mass ratio and adding both. The same applies to the polyamide (A1).
　As the polyamide (A2), 75 parts by mass of polycaproamide (polyamide 6, SP value: 26.9 (MPa) 1/2 ) in (A2X), and polyhexamethylene dodecamide in (A2Y) When (polyamide 612, SP value: 24.1 (MPa) 1/2 ) is a mixture of 25 parts by mass, the SP value of the mixture is 26.9×0.75+24.1×0.25=26. 2 (MPa) 1/2 .
　Among the polyamides (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value) having the lowest solubility parameter SP value. : 22.5 (MPa) 1/2 ) is selected, the absolute value of the difference in the solubility parameter SP value with this mixture is 3.7 (MPa) 1/2 , which is within the specified range of the present application. ..
　On the other hand, polynonamethylene azeramide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value among the above polyamides (A1) ) Is selected, the absolute value of the difference in the solubility parameter SP value with this mixture is 1.9 (MPa) 1/2 , which is within the specified range of the present application.
　As the polyamide (A2), 25 parts by mass of polycaproamide (polyamide 6, SP value: 26.9 (MPa) 1/2 ) is selected from (A2X), and polyhexamethylene dodecamide is selected from (A2Y). When the mixture (polyamide 612, SP value: 24.1 (MPa) 1/2 ) is 75 parts by mass, the SP value of the mixture is 26.9×0.25+24.1×0.75=24. 8 (MPa) 1/2 .
　Among the polyamides (A1), polydodecanamide (polyamide 12, SP value: 22.5 (MPa) 1/2 ) and/or polydodecamethylene dodecamide (polyamide 1212, SP value) having the lowest solubility parameter SP value. : 22.5 (MPa) 1/2 ) is selected, the absolute value of the difference in the solubility parameter SP value with this mixture is 3.7 (MPa) 1/2 , which is within the specified range of the present application. ..
　On the other hand, polynonamethylene azeramide (polyamide 99, SP value: 24.1 (MPa) 1/2 ) having the highest solubility parameter SP value among the above polyamides (A1) 2) is selected, the absolute value of the difference in the solubility parameter SP value with this mixture is 0.9 (MPa) 1/2 , which is outside the specified range of the present application.
　Therefore, by considering the respective SP values ​​of the polyamide (A1) and the polyamide (A2) and appropriately determining the respective mixing mass ratios, the solubility parameter SP value of the polyamide (A1) and the polyamide (A2) can be determined. The absolute value of the difference can be selected so as to satisfy 1.8 (MPa) 1/2 or more and 4.5 (MPa) 1/2 or less.
[0039]
　Examples of the production apparatus for the polyamide (A1) and the polyamide (A2) include a batch reaction kettle, a single-tank or multi-tank continuous reaction apparatus, a tubular continuous reaction apparatus, a single-screw kneading extruder, and a twin-screw kneading extruder. Known polyamide production equipment such as the kneading reaction extruder of As the polymerization method, known methods such as melt polymerization, solution polymerization and solid phase polymerization can be used, and polymerization can be carried out by repeating normal pressure, reduced pressure and pressure operations. These polymerization methods can be used alone or in an appropriate combination.
[0040]
　The relative viscosities of the polyamide (A1) and the polyamide (A2) measured under the conditions of 96% sulfuric acid, polymer concentration 1% and 25° C. according to JIS K-6920 determine the mechanical properties of the obtained laminated tube. From the viewpoints of ensuring and ensuring desirable viscosity of the laminated tube by setting the viscosity at the time of melting to an appropriate range, it is preferably 1.5 or more and 5.0 or less, and 1.8 or more and 4.5 or less. Is more preferable.
[0041]
　When the terminal amino group concentration per 1 g of the aliphatic polyamide composition (A) is [A] (μeq/g) and the terminal carboxyl group concentration is [B] (μeq/g), ethylene/vinyl acetate copolymerization described later From the viewpoint of sufficiently obtaining interlayer adhesion with the combined saponified composition (B) and its durability, [A]>[B]+10 is preferable, and [A]>[B]+15. More preferably, [A]>[B]+20 is even more preferable. Further, from the viewpoints of melt stability of the polyamide and suppression of gelled material generation, [A]>30 is preferable, and 30<[A]<140 is more preferable.
[0042]
　Here, the terminal amino group concentration per 1 g of the aliphatic polyamide composition (A) is [A] (μeq/g) and the terminal carboxyl group concentration is [B] (μeq/g) are polyamide (A1) and polyamide The respective terminal amino group concentration (μeq/g) and the terminal carboxyl group concentration (μeq/g) of (A2) are multiplied by the respective mixing mass ratios to obtain a value obtained by adding both.
　The terminal amino group concentration (μeq/g) can be measured by dissolving the polyamide in a phenol/methanol mixed solution and titrating with 0.05N hydrochloric acid. The terminal carboxyl group concentration (μeq/g) can be measured by dissolving the polyamide in benzyl alcohol and titrating with a 0.05N sodium hydroxide solution.
[0043]
　Polyamide (A1) and polyamide (A2) are produced by polymerizing or copolymerizing the polyamide raw material in the presence of amines by a known method such as melt polymerization, solution polymerization or solid phase polymerization. Alternatively, it is produced by melt-kneading in the presence of amines after polymerization. As described above, amines can be added at any stage during polymerization, or at any stage after melt-kneading after polymerization, but in consideration of the interlaminar adhesiveness of the obtained laminated tube, at the stage during polymerization. It is preferable to add.
　Examples of the amines include monoamine, diamine, triamine, tetraamine, and polyamine. In addition to amines, carboxylic acids such as monocarboxylic acids, dicarboxylic acids and tricarboxylic acids may be added, if necessary, as long as they do not fall outside the range of the terminal group concentration conditions. These amines and carboxylic acids may be added simultaneously or separately. The amines and carboxylic acids exemplified below can be used either individually or in combination of two or more.
[0044]
　Specific examples of the monoamine added include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, 2-ethylhexylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine. , Tetradecylamine, pentadecylamine, hexadecylamine, octadecylamine, octadecyleneamine, eicosylamine, docosylamine and other aliphatic monoamines; cyclohexylamine, methylcyclohexylamine and other alicyclic monoamines; benzylamine, β- Aromatic monoamines such as phenylmethylamine; N,N-dimethylamine, N,N-diethylamine, N,N-dipropylamine, N,N-dibutylamine, N,N-dihexylamine, N,N-dioctyl Symmetric secondary amines such as amines; N-methyl-N-ethylamine, N-methyl-N-butylamine, N-methyl-N-dodecylamine, N-methyl-N-octadecylamine, N-ethyl-N-hexadecyl Examples include mixed secondary amines such as amines, N-ethyl-N-octadecylamine, N-propyl-N-hexadecylamine, and N-propyl-N-benzylamine. These can use 1 type(s) or 2 or more types.
[0045]
　Specific examples of the diamine to be added include 1,2-ethanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine. , 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,15-pentadecanediamine, 1,16-hexadecanediamine, 1,17-heptadecanediamine, 1,18-octadecanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine , 2-methyl-1,8-octanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 5-methyl-1,9- Aliphatic diamines such as nonanediamine; 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane , Bis(3-methyl-4-aminocyclohexyl)methane, 2,2-bis(3-methyl-4-aminocyclohexyl)propane, 5-amino-2,2,4-trimethyl-1-cyclopentanemethylamine, 5-amino-1,3,3-trimethylcyclohexanemethylamine, bis(aminopropyl)piperazine, bis(aminoethyl)piperazine, 2,5-bis(aminomethyl)norbornane, 2,6-bis(aminomethyl)norbornane Alicyclic diamines such as 3,8-bis(aminomethyl)tricyclodecane and 4,9-bis(aminomethyl)tricyclodecane; aromatic diamines such as m-xylylenediamine and p-xylylenediamine Can be mentioned. These can use 1 type(s) or 2 or more types.
[0046]
　Specific examples of triamine and tetraamine to be added include 1,2,3-triaminopropane, 1,2,3-triamino-2-methylpropane, 1,2,4-triaminobutane, 1,2,3. 4-tetraminobutane, 1,3,5-triaminocyclohexane, 1,2,4-triaminocyclohexane, 1,2,3-triaminocyclohexane, 1,2,4,5-tetraminocyclohexane, 1,3 5-triaminobenzene, 1,2,4-triaminobenzene, 1,2,3-triaminobenzene, 1,2,4,5-tetraminobenzene, 1,2,4-triaminonaphthalene, 2,5 , 7-triaminonaphthalene, 2,4,6-triaminopyridine, 1,2,7,8-tetraminonaphthalene, 1,4,5,8-tetraminonaphthalene and the like. These can use 1 type(s) or 2 or more types.
[0047]
　The polyamine to be added may be a compound having a plurality of primary amino groups (—NH 2 ) and/or secondary amino groups (—NH—), and examples thereof include polyalkyleneimine, polyalkylenepolyamine, polyvinylamine, Examples thereof include polyallylamine. These can use 1 type(s) or 2 or more types. Amino groups with active hydrogen are the reactive sites for polyamines.
[0048]
　Polyalkyleneimine is produced by a method of ionically polymerizing an alkyleneimine such as ethyleneimine and/or propyleneimine, or a method of polymerizing an alkyloxazoline and then partially or completely hydrolyzing the polymer. .. Examples of the polyalkylene polyamine include diethylene triamine, triethylene tetramine, pentaethylene hexamine, or a reaction product of ethylene diamine and a polyfunctional compound. Polyvinylamine can be obtained, for example, by polymerizing N-vinylformamide to form poly(N-vinylformamide) and then partially or completely hydrolyzing the polymer with an acid such as hydrochloric acid. Polyallylamine is generally obtained by polymerizing a hydrochloride salt of an allylamine monomer and then removing hydrochloric acid. These can use 1 type(s) or 2 or more types. Among these, polyalkyleneimine is preferable.
[0049]
　As the polyalkyleneimine, one or two of alkyleneimines having 2 to 8 carbon atoms, such as ethyleneimine, propyleneimine, 1,2-butyleneimine, 2,3-butyleneimine, and 1,1-dimethylethyleneimine. Homopolymers and/or copolymers obtained by polymerizing one or more species by a conventional method can be mentioned. These can use 1 type(s) or 2 or more types. Among these, polyethyleneimine is more preferable. The polyalkyleneimine is obtained by polymerizing a branched polyalkyleneimine containing a primary amine, a secondary amine, and a tertiary amine obtained by ring-opening polymerization of the alkyleneimine as a raw material, or an alkyloxazoline as a raw material. Any of a linear polyalkyleneimine containing only the primary amine and the secondary amine obtained in this way, or a three-dimensionally crosslinked structure may be used. Further, those obtained by copolymerizing monomers such as ethylenediamine, propylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, tripropylenetetramine, dihexamethylenetriamine, aminopropylethylenediamine and bisaminopropylethylenediamine. May be The polyalkyleneimine is usually derived from the reactivity of the active hydrogen atom on the contained nitrogen atom, and in addition to the tertiary amino group, a primary amino group and/or a secondary amino group having an active hydrogen atom. (Imino group).
[0050]
　The number of nitrogen atoms in the polyalkyleneimine is not particularly limited and is preferably 4 or more and 3,000, more preferably 8 or more and 1,500 or less, and further preferably 11 or more and 500 or less. The number average molecular weight of the polyalkyleneimine is preferably 100 or more and 20,000 or less, more preferably 200 or more and 10,000 or less, and further preferably 500 or more and 8,000 or less.
[0051]
　On the other hand, as carboxylic acids to be added, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, capric acid, pelargonic acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, myristoleic acid, Aliphatic monocarboxylic acids such as palmitic acid, stearic acid, oleic acid, linoleic acid, arachidic acid, behenic acid, and erucic acid; cycloaliphatic monocarboxylic acids such as cyclohexanecarboxylic acid and methylcyclohexanecarboxylic acid; benzoic acid and toluic acid Aromatic monocarboxylic acids such as ethyl benzoic acid and phenylacetic acid; malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, hexadecanedioic acid , Hexadecenedioic acid, octadecanedioic acid, octadecenedioic acid, eicosanedioic acid, eicosenedioic acid, docosanedioic acid, diglycolic acid, 2,2,4-trimethyladipic acid, 2,4,4-trimethyladipic acid, etc. Aliphatic dicarboxylic acids; alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, norbornanedicarboxylic acid; terephthalic acid, isophthalic acid, phthalic acid, m-xylylenedicarboxylic acid, p- Aromatic dicarboxylic acids such as xylylenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid; 1,2,4-butanetricarboxylic acid, 1,3,5 Examples include tricarboxylic acids such as pentanetricarboxylic acid, 1,2,6-hexanetricarboxylic acid, 1,3,6-hexanetricarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid and trimesic acid. These can use 1 type(s) or 2 or more types.
[0052]
　The amount of amines to be added is appropriately determined by a known method in consideration of the terminal amino group concentration, terminal carboxyl group concentration and relative viscosity of the polyamide (A1) and polyamide (A2) to be produced. Usually, the amount of amines added to 1 mol of the polyamide raw material (monomer constituting the repeating unit or 1 mol of the monomer unit) is such that a polyamide having a desired viscosity and sufficient reactivity can be obtained. From the viewpoint of facilitating the production, it is preferably 0.5 meq/mol or more and 20 meq/mol or less, and more preferably 1 meq/mol or more and 10 meq/mol or less (equivalent (eq) of amino group is a carboxyl group). And 1:1 (molar ratio) to form an amide group to form an amino group.
[0053]
　In the polyamide (A1) and the polyamide (A2), it is preferable to add a diamine and/or a polyamine during the polymerization in order to satisfy the condition of the terminal group concentration among the amines exemplified above, from the viewpoint of suppressing gel generation. It is more preferable to add at least one selected from the group consisting of an aliphatic diamine, an alicyclic diamine, and a polyalkyleneimine during polymerization.
[0054]
　[Elastomer polymer (A3)] The
　aliphatic polyamide composition (A) contains an elastomer polymer (A3) containing a structural unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group. (Hereinafter, it may be referred to as an elastomer polymer (A3).).
　As the elastomer polymer (A3), an (ethylene and/or propylene)/α-olefin copolymer containing a constitutional unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, ( Examples thereof include ethylene and/or propylene)/(α,β-unsaturated carboxylic acid ester)-based copolymers and aromatic vinyl compound/conjugated diene compound-based block copolymers, and these are used alone or in combination of two or more. be able to.
[0055]
　The (ethylene and/or propylene)/α-olefin copolymer is a copolymer of ethylene and/or propylene and α-olefin having 3 or more carbon atoms, and α-olefin having 3 or more carbon atoms. Examples of the olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4- Methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene and the like can be mentioned. These can use 1 type(s) or 2 or more types. Further, 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,4-octadiene, 1,5-octadiene, 1,6-octadiene, 1,7-octadiene, 2-methyl-1, 5-hexadiene, 6-methyl-1,5-heptadiene, 7-methyl-1,6-octadiene, 4-ethylidene-8-methyl-1,7-nonadiene, 4,8-dimethyl-1,4,8- Decatriene (DMDT), dicyclopentadiene, cyclohexadiene, cyclooctadiene, 5-vinyl norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 6-chloromethyl Of non-conjugated dienes such as -5-isopropenyl-2-norbornene, 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene and 2-propenyl-2,5-norbornadiene. Polyene may be copolymerized. These can use 1 type(s) or 2 or more types.
[0056]
　The (ethylene and/or propylene)/(α,β-unsaturated carboxylic acid ester)-based copolymer is a polymer obtained by copolymerizing ethylene and/or propylene with an α,β-unsaturated carboxylic acid ester monomer. The α,β-unsaturated carboxylic acid ester monomer, which is a combination, includes methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate. , Pentyl acrylate, Pentyl methacrylate, Hexyl acrylate, Hexyl methacrylate, Heptyl acrylate, Heptyl methacrylate, Octyl acrylate, Octyl methacrylate, Nonyl acrylate, Nonyl methacrylate, Decyl acrylate, Decyl methacrylate, Acrylic Examples thereof include 2-ethylhexyl acid, 2-ethylhexyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, monomethyl maleate, monomethyl itaconate, dimethyl maleate and dimethyl itaconate. These can use 1 type(s) or 2 or more types.
[0057]
　The aromatic vinyl compound/conjugated diene compound-based block copolymer is a block copolymer composed of an aromatic vinyl compound-based polymer block and a conjugated diene compound-based polymer block. A block copolymer having at least one block and at least one conjugated diene compound-based polymer block is used. In the block copolymer, the unsaturated bond in the conjugated diene compound-based polymer block may be hydrogenated.
[0058]
　The aromatic vinyl compound-based polymer block is a polymer block mainly composed of units derived from an aromatic vinyl compound. Examples of the aromatic vinyl compound in that case include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 1,5-dimethylstyrene, 2,4-dimethylstyrene, vinylnaphthalene, vinylanthracene, and 4-propyl. Examples thereof include styrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene, and these may be used alone or in combination of two or more. The aromatic vinyl compound-based polymer block may optionally have a small amount of a unit composed of another unsaturated monomer.
[0059]
　The conjugated diene compound-based polymer block includes 1,3-butadiene, chloroprene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 4-methyl-1,3-pentadiene, 1,3 A polymer block formed from one or more conjugated diene compounds such as hexadiene, which is a hydrogenated aromatic vinyl compound/conjugated diene compound block copolymer, the conjugated diene compound polymer A part or all of the unsaturated bond portions in the block are saturated bonds by hydrogenation.
　The molecular structure of the aromatic vinyl compound/conjugated diene compound-based block copolymer and the hydrogenated product thereof may be linear, branched, radial, or any combination thereof. Among these, as the aromatic vinyl compound/conjugated diene compound-based block copolymer and/or hydrogenated product thereof, one aromatic vinyl compound polymer block and one conjugated diene compound-based polymer block are linear. Of three linearly linked diblock copolymers, aromatic vinyl compound-based polymer block-conjugated diene compound-based polymer block-aromatic vinyl compound-based polymer block One or more kinds of triblock copolymers and hydrogenated products thereof are preferably used. Unhydrogenated or hydrogenated styrene/butadiene block copolymer, unhydrogenated or hydrogenated styrene/isoprene block copolymer Polymer, unhydrogenated or hydrogenated styrene/butadiene/styrene block copolymer, unhydrogenated or hydrogenated styrene/isoprene/styrene block copolymer, unhydrogenated or hydrogenated styrene/(ethylene/butadiene)/styrene Examples thereof include block copolymers, unhydrogenated or hydrogenated styrene/(isoprene/butadiene)/styrene block copolymers. These can use 1 type(s) or 2 or more types.
[0060]
　Examples of the unsaturated compound having a carboxyl group that forms the constitutional unit of the elastomer polymer (A3) include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, mesaconic acid, citraconic acid, glutaconic acid, cis. -4-Cyclohexene-1,2-dicarboxylic acid, endobicyclo-[2.2.1]-5-heptene-2,3-dicarboxylic acid, and α,β-unsaturated carboxylic acids such as metal salts of these carboxylic acids An acid is mentioned. These can use 1 type(s) or 2 or more types. Examples of the unsaturated compound having an acid anhydride group that forms the constituent unit of the elastomer polymer (A3) include maleic anhydride, itaconic anhydride, citraconic anhydride, and endobicyclo-[2.2.1]-5-heptene. Examples thereof include dicarboxylic acid anhydrides having an α,β-unsaturated bond such as -2,3-dicarboxylic acid anhydride. These can use 1 type(s) or 2 or more types. Among these, dicarboxylic acid anhydrides having an α,β-unsaturated bond are preferable, and maleic anhydride and itaconic anhydride are more preferable.
[0061]
　The carboxyl group and/or acid anhydride group concentration in the elastomer polymer (A3) is effective in improving low-temperature impact resistance, interlayer adhesion with the ethylene/vinyl acetate copolymer saponified composition (B) described below, and durability thereof. From the viewpoint of obtaining sufficient property and fluidity of the resulting aliphatic polyamide composition (A), it is preferably 25 μeq/g or more and 200 μeq/g or less, and 50 μeq/g or more and 150 μeq/g or less. More preferable.
[0062]
　The concentration of the carboxyl group and/or acid anhydride group in the elastomer polymer (A3) was determined by dissolving the elastomer polymer in a toluene solution, and adding ethanol to prepare a sample solution of phenolphthalein. It can be measured by titrating with a 0.1 N KOH ethanol solution as an indicator.
[0063]
　Content of polyamide (A1) in aliphatic polyamide composition (A) is 40 mass% or more and 85 mass% or less, and 47 mass% or more 80 with respect to 100 mass% of aliphatic polyamide composition (A). It is preferably not more than mass%, more preferably not less than 55 mass% and not more than 75 mass%. Further, the lower limit of the content of the polyamide (A1) in the aliphatic polyamide composition (A) may be 50% by mass or more, or 52% by mass or more. When the content of the polyamide (A1) is less than the above value, the mechanical properties and low temperature impact resistance of the obtained laminated tube may be poor, while when it exceeds the above value, the interlayer of the obtained laminated tube may be deteriorated. The adhesiveness and its durability may be poor.
[0064]
　Content of the polyamide (A2) in the aliphatic polyamide composition (A) is 10% by mass or more and 30% by mass or less, and 12% by mass or more 28% with respect to 100% by mass of the aliphatic polyamide composition (A). It is preferably not more than 15% by mass, more preferably not less than 15% by mass and not more than 25% by mass. When the content of the polyamide (A2) is less than the above value, the interlayer adhesion and durability of the obtained laminated tube may be poor, while when it exceeds the above value, the mechanical properties of the obtained laminated tube are poor. Poor properties and chemical resistance.
[0065]
　The content of the elastomer polymer (A3) in the aliphatic polyamide composition (A) is 5% by mass or more and 30% by mass or less, and 8% by mass with respect to 100% by mass of the aliphatic polyamide composition (A). It is preferably 25% by mass or more and more preferably 10% by mass or more and 20% by mass or less. When the content of the elastomer polymer (A3) is less than the above-mentioned value, the low temperature impact resistance, interlayer adhesion and durability of the obtained laminated tube may be poor, while when it exceeds the above-mentioned value. In some cases, the resulting laminated tube has poor mechanical properties and the resulting aliphatic polyamide composition (A) has poor fluidity.
[0066]
　The method of mixing the polyamide (A1) and the polyamide (A2) with the elastomer polymer (A3) is not particularly limited, and various additives are added as necessary, and various conventionally known methods are adopted. be able to. For example, a method of uniformly dry blending the pellets of the polyamide (A1), the polyamide (A2), and the elastomer polymer (A3) with each other using a tumbler and/or a mixer so that the mixing ratio becomes the above, Can be produced by a method such as dry blending in advance with other components added as necessary at a concentration used during molding, and melt kneading. The melt-kneading can be performed using a kneading machine such as a single-screw extruder, a twin-screw extruder, a kneader, a Banbury mixer.
[0067]
　The aliphatic polyamide composition (A) may be a mixture with other thermoplastic resin. The total content of the polyamide (A1), the polyamide (A2), and the elastomer polymer (A3) is preferably 80% by mass or more, and 85% by mass with respect to 100% by mass of the aliphatic polyamide composition (A). % Or more is more preferable.
[0068]
　Examples thereof include fluorocarbon resins such as (alkyl vinyl ether)/tetrafluoroethylene copolymer (CPT). These can use 1 type(s) or 2 or more types.
[0069]
　Furthermore, if necessary, the aliphatic polyamide composition (A) contains an antioxidant, a heat stabilizer, an ultraviolet absorber, a light stabilizer, a lubricant, an inorganic filler, an antistatic agent, a flame retardant, and crystallization. Accelerators, colorants and the like may be added.
[0070]
　2. The (b) layer of the (b) layer
　laminated tube contains the ethylene/vinyl acetate copolymer saponified composition (B). The saponified ethylene/vinyl acetate copolymer composition (B) contains a saponified ethylene/vinyl acetate copolymer (B1).
[0071]
[Saponified Ethylene/Vinyl Acetate Copolymer (B1)] The
　saponified ethylene/vinyl acetate copolymer (B1) is a copolymer composed of an ethylene monomer and a vinyl acetate monomer (ethylene/vinyl acetate copolymer). It can be obtained by saponifying (combined) (hereinafter sometimes referred to as EVOH (B1)).
[0072]
　Further, from the viewpoint of sufficiently ensuring melt moldability, flexibility, impact resistance, and chemical solution barrier property, the total amount of ethylene units and vinyl acetate units is 100 mol%, and ethylene units in EVOH (B1) The content is preferably 15 mol% or more and 60 mol% or less, more preferably 20 mol% or more and 55 mol% or less, and further preferably 25 mol% or more and 45 mol% or less.
[0073]
　Further, other monomers can be copolymerized as long as they do not impair the excellent properties of the obtained laminated tube. Other monomers include vinyl formate, vinyl propionate, vinyl valerate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl itaconate, vinyl caproate, vinyl caprylate, vinyl caprate, 2-ethylhexane. Vinyl acetate, vinyl neononanoate, vinyl neodecanoate, vinyl versaticate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate, vinyl oleate, isopropenyl acetate, 1-butenyl acetate, vinyl chloroacetate, trifluoro acetate. Vinyl esters such as vinyl acetate, vinyl methacrylate, vinyl crotonate, vinyl adipate, vinyl sorbate, vinyl cyclohexanecarboxylate, vinyl benzoate, vinyl pt-butyl benzoate, vinyl acetylsalicylate, vinyl cinnamate; Α-Olefins such as propylene, 1-butene, isobutene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-dodecene; acrylic acid, methacrylic acid, crotonic acid, phthalic acid, maleic anhydride Acids, unsaturated acids such as (anhydrous) itaconic acid or salts thereof, or mono- or dialkyl esters having 1 to 18 carbon atoms; acrylamide, N-alkyl acrylamide having 1 to 18 carbon atoms, N,N- Acrylamides such as dimethylacrylamide, 2-acrylamidopropanesulfonic acid or a salt thereof, acrylamidopropyldimethylamine or an acid salt thereof or a quaternary salt thereof; methacrylamide, N-alkylmethacrylamide having 1 to 18 carbon atoms, N, Methacrylamides such as N-dimethylmethacrylamide, 2-methacrylamidopropanesulfonic acid or salts thereof, methacrylamidopropyldimethylamine or acid salts thereof or quaternary salts thereof; N-vinylpyrrolidone, N-vinylformamide, N-vinyl N-vinylamides such as acetamide; vinyl cyanides such as acrylonitrile and methacrylonitrile; carbon atoms of 1 or more Vinyl ethers of 18 or less alkyl vinyl ether, hydroxyalkyl vinyl ether, alkoxyalkyl vinyl ether and the like; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride and vinyl bromide; vinyltrimethoxysilane, vinylmethyl Vinylsilanes such as dimethoxysilane, vinyldimethylmethoxylan, vinyltriethoxysilane, vinylmethyldiethoxysilane, vinyldimethylethoxysilane γ-methacryloxypropylmethoxysilane; allyl acetate, allyl chloride, allyl alcohol, dimethylallyl alcohol, trimethyl- Examples thereof include (3-acrylamido-3-dimethylpropyl)-ammonium chloride, acrylamido-2-methylpropanesulfonic acid, vinylethylene carbonate and the like. These can use 1 type(s) or 2 or more types. The content of these other monomers is preferably 5 mol% or less, more preferably 3 mol% or less, and more preferably 2 mol% with respect to 100 mol% of all the polymerized units in EVOH (B1). % Or less is more preferable.
[0074]
　The ethylene/vinyl acetate copolymer can be polymerized by any known polymerization method such as batch polymerization, semi-batch polymerization, continuous polymerization and semi-continuous polymerization. As the polymerization method, any known method such as a known polymerization method, a bulk polymerization method, a solution polymerization method, a suspension polymerization method and an emulsion polymerization method can be adopted. A bulk polymerization method or a solution polymerization method in which the polymerization proceeds in the absence of solvent or in a solvent such as alcohol is usually adopted.
　The ethylene/vinyl acetate copolymer is obtained by copolymerizing ethylene and vinyl acetate monomer under the pressure of ethylene gas by the above method. The solvent used in the solution polymerization method is not particularly limited, but alcohols are preferable, and lower alcohols such as methanol, ethanol and propanol are more preferable. The amount of the solvent used in the polymerization reaction solution may be selected in consideration of the degree of polymerization of the intended ethylene/vinyl acetate copolymer and the chain transfer of the solvent.
[0075]
　Examples of the polymerization initiator used when polymerizing the ethylene/vinyl acetate copolymer include known polymerization initiators such as azo initiators, peroxide initiators and redox initiators. The polymerization initiator is selected according to the polymerization method. Examples of the azo-based initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(4-methoxy-2, 4-dimethylvaleronitrile) and the like, and examples of the peroxide-based initiator include diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and diethoxy. Percarbonate compounds such as ethyl peroxydicarbonate and bis-(4-t-butylcyclohexyl)peroxy-di-carbonate; t-butyl peroxyneodecanate, t-butyl peroxypivalate, t-hexyl peroxy Perester compounds such as pivalate and α-cumylperoxyneodecanate; isobutyral peroxide, acetyl peroxide, di-lauroyl peroxide, di-decanoyl peroxide, di-octanoyl peroxide, di-propyl Examples thereof include peroxide compounds such as peroxide and benzoyl peroxide; acetylcyclohexylsulfonyl peroxy, 2,4,4-trimethylpentyl-2-peroxyphenoxyacetate and the like. These can use 1 type(s) or 2 or more types. Further, potassium persulfate, ammonium persulfate, hydrogen peroxide and the like may be used in combination with the above initiator. The redox initiator is, for example, a polymerization initiator in which the above-mentioned peroxide initiator is combined with a reducing agent such as sodium hydrogen sulfite, sodium hydrogen carbonate, tartaric acid, L-ascorbic acid, and Rongalit. These can use 1 type(s) or 2 or more types.
　The amount of the polymerization initiator used cannot be determined unconditionally because it varies depending on the polymerization catalyst, but it is adjusted according to the polymerization rate, and the amount used is 0.01 mol% or more based on the vinyl acetate monomer. It is preferably 0.2 mol% or less, and more preferably 0.02 mol% or more and 0.15 mol% or less. The polymerization temperature is not particularly limited, but is preferably room temperature or higher and 150° C. or lower, and more preferably 30° C. or higher and the boiling point or lower of the solvent used.
[0076]
　When the ethylene/vinyl acetate copolymer is polymerized, it may be copolymerized in the presence of a chain transfer agent as long as the effect of the present invention is not impaired. Examples of the chain transfer agent include aldehydes such as acetaldehyde and propionaldehyde; ketones such as acetone and methyl ethyl ketone; mercaptans such as 2-hydroxyethanethiol; phosphinates such as sodium phosphinate monohydrate. To be These can use 1 type(s) or 2 or more types. Among these, aldehydes and/or ketones are preferable. The amount of the chain transfer agent added to the polymerization reaction solution is determined according to the chain transfer coefficient of the chain transfer agent and the desired degree of polymerization of EVOH (B1), but generally 100 parts by mass of vinyl acetate monomer is used. On the other hand, it is preferably 0.1 part by mass or more and 10 parts by mass or less.
[0077]
　For the saponification of the obtained ethylene/vinyl acetate copolymer, a known saponification method can be adopted. The saponification reaction is usually carried out in a solution of alcohol or hydrous alcohol. The alcohol used at this time is preferably a lower alcohol such as methanol or ethanol, more preferably methanol. The alcohol or hydrous alcohol used in the saponification reaction may contain other solvents such as acetone, methyl acetate, ethyl acetate and benzene as long as the content is 40% by mass or less. Examples of the catalyst used for saponification include alkali metal hydroxides such as potassium hydroxide, sodium hydroxide, sodium methylate, sodium ethylate, potassium methylate and lithium methylate, and alkali catalysts such as alcoholate; Examples thereof include acid catalysts such as sulfuric acid, hydrochloric acid, nitric acid, mineral acid, metasulfonic acid, zeolite, and cation exchange resin. These can use 1 type(s) or 2 or more types. The temperature for saponification when using the alkali catalyst is not particularly limited, but is preferably 20° C. or higher and 120° C. or lower.
[0078]
　Further, the saponification degree of the vinyl acetate unit in EVOH (B1) is preferably 90 mol% or more, more preferably 95 mol% or more, and 98% from the viewpoint of obtaining a good chemical liquid barrier property. It is more preferably at least mol, and particularly preferably at least 99 mol %. Here, the degree of saponification of EVOH (B1) (content of vinyl acetate units in the EVOH (B1) that have become vinyl alcohol units by saponification) is JIS K 6726 (provided that EVOH (B1) Is a solution uniformly dissolved in a water/methanol solvent).
[0079]
　The melt flow rate (MFR) of EVOH (B1) (210° C., under a load of 2,160 g) ensures a desirable moldability by setting the viscosity at the time of melting to an appropriate range, and does not excessively reduce the melt tension during molding. From the viewpoint of preventing problems such as drawdown, it is preferably 0.1 g/10 minutes or more and 100 g/10 minutes or less, more preferably 0.3 g/10 minutes or more and 50 g/10 minutes or less, It is more preferably 0.5 g/10 minutes or more and 20 g/10 minutes or less.
[0080]
　EVOH (B1) is not limited to one kind, but EVOH (B1) having a different degree of saponification, EVOH (B1) having a different molecular weight, EVOH (B1) having a different kind of other copolymerizable monomers, etc., 2 You may use combining EVOH (B1) of a kind or more.
[0081]
　EVOH (B1) may be used together with EVOH (B1) having different ethylene unit contents. When the ethylene units having different ethylene unit contents are used together, the other units may be the same or different, but the difference in the ethylene unit contents is preferably 1 mol% or more. It is more preferably at least mol%, further preferably at least 2 mol% and not more than 20 mol%.
[0082]
　When two or more different EVOH (B1) are blended and used, the method for producing the blend is not particularly limited. For example, a method in which each paste of ethylene/vinyl acetate copolymer before saponification is mixed and then saponified, and a solution in which each EVOH (B1) after saponification is dissolved in alcohol or a mixed solvent of water and alcohol is mixed. Examples of the method include a method of mixing pellets or powder of each EVOH (B1) and then melt-kneading.
[0083]
　The ethylene/vinyl acetate copolymer saponified composition (B) may contain various additives as required. Examples of such additives include antioxidants, plasticizers, stabilizers, ultraviolet absorbers, antistatic agents, lubricants, colorants, fillers, oxygen absorbers, and other thermoplastic resins. It is possible to add these additives within a range that does not impair the excellent properties of the obtained laminated tube. Specifically, 2,5-di-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 4,4′-thiobis(6-t-butyl-m-cresol), 4, 4'-thiobis(6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 2,2'-methylene-bis(4-methyl-6-t-butylphenol) , 2,2'-methylenebis(4-ethyl-6-t-butylphenol), n-octadecyl-β-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate, N,N' -Hexamethylenebis(3,5-di-t-butyl-4-hydroxyhydrocinnamide), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1, 3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tetrakis[methylene-3-(3',5'-di-t-butyl- 4′-hydroxyphenyl)propionate], benzeneerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], tris(2,4-di-t-butylphenyl), Antioxidants such as di(2,4-di-t-butylphenyl)-pentaerythritol-diphosphite; ethylene-2-cyano-3,3'-diphenyl acrylate, 2-(2'-hydroxy-5'- Methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy- Four -Ultraviolet absorbers such as methoxybenzophenone and 2-hydroxy-4-octoxybenzophenone; plasticizers such as dimethyl phthalate, diethyl phthalate and dioctyl phthalate; pentaerythritol monostearate, sorbitan monopalmitate, sulfated polyolefin Antistatic agents such as aliphatic polyhydric alcohols such as ethylene glycol, glycerin, and hexanediol; saturated fatty acid amides such as stearic acid amide; unsaturated fatty acid amides such as oleic acid amide; bis such as ethylenebisstearic acid amide Fatty acid amides, fatty acid metal salts such as calcium stearate, magnesium stearate, zinc stearate and aluminum stearate, lubricants such as wax, liquid paraffin and low molecular weight polyolefins; organic acids such as acetic acid, propionic acid and stearic acid; hydrotalcite Stabilizers such as metal salts; oxygen absorbers such as reduced iron powder, potassium sulfite, ascorbic acid, hydroquinone and gallic acid; coloring agents such as carbon black, phthalocyanine, quinacridone, indoline, azo pigments and red iron oxide; glass Examples thereof include fillers such as fiber, asbestos, ballastonite, mica, sericite, talc, silica, kaolin, calcium silicate and montmorillonite. These can use 1 type(s) or 2 or more types.
[0084]
　Further, the saponified ethylene/vinyl acetate copolymer composition (B) preferably contains a boron atom-containing compound. The inclusion of the boron atom-containing compound is effective from the viewpoint of improving melt stability and obtaining a laminated tube having a uniform wall thickness. Examples of the boron atom-containing compound include boric acids, boric acid esters, borate salts, and borohydrides. Examples of the boric acid include orthoboric acid, metaboric acid, tetraboric acid, and the like, examples of the borate ester include triethyl borate, trimethyl borate, and the like. Examples thereof include metal salts, alkaline earth metal salts and borax. These can use 1 type(s) or 2 or more types. Among these, orthoboric acid is preferable.
[0085]
　The content of the boron atom-containing compound in the saponified ethylene/vinyl acetate copolymer composition (B) is 100% by mass of EVOH (B1) from the viewpoint of sufficiently securing the effect of inclusion and obtaining a laminated tube having a good appearance. The amount is preferably 0.002 parts by mass or more and 0.5 parts by mass or less, and more preferably 0.005 parts by mass or more and 0.2 parts by mass or less, in terms of boron atom concentration.
[0086]
　The saponified ethylene/vinyl acetate copolymer composition (B) may contain a phosphoric acid compound. By containing a phosphoric acid compound, long run property at the time of melt molding, color resistance, and interlayer adhesiveness can be achieved at the same time. The phosphoric acid compound is not particularly limited, and various acids such as phosphoric acid and phosphorous acid and salts thereof can be used. Examples of the phosphate include primary phosphate, secondary phosphate, tertiary phosphate and the like. These can use 1 type(s) or 2 or more types. The cation species of the phosphate is also not particularly limited, but alkali metal salts are preferable, and among these, sodium phosphate, lithium phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, dihydrogen phosphate are preferred. Sodium and dipotassium hydrogen phosphate are preferred.
[0087]
　The content of the phosphoric acid compound in the saponified ethylene/vinyl acetate copolymer composition (B) is 100 parts by mass of EVOH (B1) from the viewpoint of sufficiently securing the effect of inclusion and obtaining a laminated tube having a good appearance. On the other hand, it is preferably 0.02 parts by mass or less, more preferably 0.0005 parts by mass or more and 0.01 parts by mass or less, and 0.001 parts by mass or more and 0.007 parts by mass in terms of phosphate concentration. It is more preferable that the amount is not more than part.
[0088]
　It is also preferable from the viewpoint of melt stability and long-run property that the saponified ethylene/vinyl acetate copolymer composition (B) contains an alkali metal salt and/or an alkaline earth metal salt. The alkali metal salt and/or the alkaline earth metal salt refer to compounds other than the phosphoric acid compound. The anion species of the alkali metal and alkaline earth metal salts are not particularly limited, and examples thereof include carboxylates, hydroxides, carbonates, hydrogen carbonates and the like. There is no limitation on the cation species of the alkali metal salt, and examples thereof include lithium salt, sodium salt, potassium salt, etc., and there is no limitation on the cation species of the alkaline earth metal salt, magnesium salt, calcium salt, barium salt, beryllium salt, strontium. Salt etc. are mentioned. Specifically, sodium acetate, lithium acetate, potassium acetate, calcium palmitate, magnesium palmitate, calcium myristate, magnesium myristate, calcium stearate, magnesium stearate, calcium oleate, magnesium oleate, calcium linoleate, linole. Examples thereof include magnesium acid salt, calcium linolenate, and magnesium linolenate. These can use 1 type(s) or 2 or more types.
[0089]
　The content of the alkali metal salt and/or the alkaline earth metal salt in the saponified ethylene/vinyl acetate copolymer composition (B) is from the viewpoint of sufficiently securing the effect of inclusion and obtaining a laminated tube having a good appearance. , 0.0005 parts by mass or more and 0.2 parts by mass or less, and 0.001 parts by mass or more and 0.1 parts by mass or less, in terms of metal atom concentration, based on 100 parts by mass of EVOH (B1). Is more preferable and 0.002 parts by mass or more and 0.05 parts by mass or less is further preferable.
[0090]
　In addition, in the saponified ethylene/vinyl acetate copolymer composition (B), in order to improve the melt stability and the like, within the above-mentioned additives within the range that does not impair the excellent properties of the obtained laminated tube. It is preferable to use one or more of a stabilizer which is a metal salt of hydrotalcites and a hindered phenolic antioxidant, and the content of the stabilizer and/or the antioxidant is EVOH(B1). It is preferable to add 0.01 part by mass or more and 1 part by mass or less to 100 parts by mass.
[0091]
　Furthermore, it is preferable to add an impact modifier to the saponified ethylene/vinyl acetate copolymer composition (B) in order to improve the low temperature impact resistance of EVOH (B1). It is more preferable to add the elastomer polymer (B2) containing a constitutional unit derived from an unsaturated compound having an anhydride group. Examples of the elastomer polymer (B2) include those exemplified as the elastomer polymer (A3) contained in the aliphatic polyamide composition (A). The elastomer polymer (B2) may be the same as or different from the elastomer polymer (A3). These can use 1 type(s) or 2 or more types. When the elastomer polymer (B2) contains a structural unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, the impact improving effect is sufficient.
　The content of the impact modifier is 1 part by mass with respect to 100 parts by mass of the main component EVOH (B1), from the viewpoint of sufficiently securing the mechanical strength, flexibility and low temperature impact resistance of the obtained laminated tube. The amount is preferably 30 parts by mass or more and more preferably 3 parts by mass or more and 25 parts by mass or less.
[0092]
　The saponified ethylene/vinyl acetate copolymer composition (B) may contain other thermoplastic resin. Examples of the other thermoplastic resin include the same resins as the other thermoplastic resins described in the description of the aliphatic polyamide composition (A). These can use 1 type(s) or 2 or more types. Further, from the viewpoint of sufficiently ensuring flexibility and elongation of the obtained laminated tube, the polyamide described in the description of the polyamide (A1) and/or the polyamide (A2) contained in the aliphatic polyamide composition (A) is used. It is also preferably a mixture. It is also preferable to include a polyamide elastomer such as a polyether ester amide elastomer or a polyether amide elastomer, or a polyester elastomer. The content of EVOH (B1) in the saponified ethylene/vinyl acetate copolymer composition (B) is preferably 60% by mass or more, and more preferably 70% by mass or more.
[0093]
　3. The (c) layer
　laminated tube preferably further has (c) layer.
　Layer (c) of the laminated tube contains the polyamide composition (C).
[0094]
　The polyamide composition (C) contains the polyamide (C1) and an elastomer polymer (C2), and the polyamide (C1) has a melting point of 210° C. or less measured according to “ISO 11357-3, 70% by mass or more and 95% by mass relative to 100% by mass of the total of the polyamide (C1) and the elastomer polymer (C2), which is a polyamide other than the "aliphatic polyamide having a ratio of the number of methylene groups to the number of amide groups of 8.0 or more". Included below, the elastomer polymer (C2) contains a structural unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, and the total amount of the polyamide (C1) and the elastomer polymer (C2) is 100. It is contained in an amount of 5% by mass or more and 30% by mass or less with respect to% by mass (hereinafter, may be referred to as a polyamide composition (C)).
　Further, it is preferable that the polyamide composition (C) does not contain a plasticizer from the viewpoint of durability of interlayer adhesion after being contacted and dipped in fuel for a long time and/or after heat treatment for a short time.
[0095]
　Examples of the polyamide (C1) include those exemplified as the polyamide (A2) contained in the aliphatic polyamide composition (A). The polyamide (C1) may be the same as or different from the polyamide (A2). These can use 1 type(s) or 2 or more types.
　The content of the polyamide (C1) in the polyamide composition (C) is 70% by mass or more and 95% by mass based on 100% by mass based on 100% by mass of the total amount of the polyamide (C1) and the elastomer polymer (C2). % Or less, more preferably 75% by mass or more and 93% by mass or less, and particularly preferably 80% by mass or more and 90% by mass or less. When the content of the polyamide (C1) is at least the above value with respect to 100% by mass of the total of the polyamide (C1) and the elastomer polymer (C2), it is advantageous in terms of mechanical properties of the obtained laminated tube. On the other hand, when the value is not more than the above value, it is advantageous in low temperature impact resistance and chemical resistance of the obtained laminated tube.
[0096]
　Examples of the elastomer polymer (C2) include those exemplified as the elastomer polymer (A3) contained in the aliphatic polyamide composition (A). The elastomer polymer (C2) may be the same as or different from the elastomer polymer (A3). These can use 1 type(s) or 2 or more types.
　The content of the elastomer polymer (C2) in the polyamide composition (C) is 5% by mass or more and 30% by mass or less based on 100% by mass of the total amount of the polyamide (C1) and the elastomer polymer (C2). Is preferred, 7% by mass or more and 25% by mass or less is more preferred, and 10% by mass or more and 20% by mass or less is particularly preferred. When the content of the elastomeric polymer (C2) is at least the above value based on 100% by mass of the total amount of the polyamide (C1) and the elastomeric polymer (C2), the resulting laminated tube has low temperature impact resistance and interlayer properties. Adhesiveness and durability thereof are advantageous, and on the other hand, when it is at most the above value, it is advantageous in terms of mechanical properties of the obtained laminated tube and fluidity of the obtained polyamide composition (C).
[0097]
　As a method of mixing the polyamide (C1) and the elastomer polymer (C2), the known method described in the description of the aliphatic polyamide composition (A) can be mentioned.
[0098]
　The polyamide composition (C) may contain other thermoplastic resin. Examples of the other thermoplastic resin include the same resins as the other thermoplastic resins described in the description of the aliphatic polyamide composition (A). These can use 1 type(s) or 2 or more types. The total content of the polyamide (C1) and the elastomer polymer (C2) in the polyamide composition (C) is preferably 80% by mass or more, and more preferably 90% by mass or more.
[0099]
　Furthermore, if necessary, the polyamide composition (C) contains an antioxidant, a heat stabilizer, an ultraviolet absorber, a light stabilizer, a lubricant, an inorganic filler, an antistatic agent, a flame retardant, a crystallization accelerator. , A colorant, a lubricant and the like may be added.
[0100]
　4. The (d) layer
　laminated tube preferably further has a (d) layer.
　Layer (d) of the laminated tube contains a semi-aromatic polyamide composition (D).

The scope of the claims
[Claim 1]
　A double- or more layered tube containing the (a) layer and the (b) layer,
　the at least one pair of said (a) layer and the (b) layer, disposed adjacent,
　wherein (a) The layer comprises an aliphatic polyamide composition (A), the
　(b) layer comprises an ethylene/vinyl acetate copolymer saponified composition (B), and the
　aliphatic polyamide composition (A) is a polyamide. (A1), polyamide (A2), and elastomer polymer (A3), the
　polyamide (A1) has a melting point of 210° C. or less measured according to ISO 11357-3, and the number of amide groups is the number of methylene groups. To 80% by mass or more and 85% by mass or less in the aliphatic polyamide composition (A), and the
　polyamide (A2) is other than the polyamide (A1). 10% by mass or more and 30% by mass or less of the aliphatic polyamide composition (A), and the
　elastomer polymer (A3) is unsaturated having a carboxyl group and/or an acid anhydride group. A
　solubility parameter of the polyamide (A1) and the polyamide (A2), which contains a structural unit derived from a compound and is contained in the aliphatic polyamide composition (A) in an amount of 5% by mass or more and 30% by mass or less. The absolute value of the difference in SP value [|(SP value of polyamide (A1))-(SP value of polyamide (A2))|] is 1.8 (MPa) 1/2 or more and 4.5 (MPa) 1/ Laminated tube that is 2 or less.
[Claim 2]
　The polyamide (A1) is polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide 1010), polydecamethylene dodecamide (polyamide 1012), polydodecamethylene dodecamide (polyamide 1212), polyundecane. At least one homopolymer selected from the group consisting of amides (polyamide 11) and polydodecanamide (polyamide 12), and/or at least one co-polymer containing several raw material monomers forming them. The laminated tube according to claim 1, which is a united body.
[Claim 3]
　The polyamide (A2) is polycaproamide (polyamide 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azeramide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), and polyhexa. At least one homopolymer selected from the group consisting of methylenedodecamide (polyamide 612), and/or at least one copolymer using several raw material monomers forming these, or the above polycapro It consists of amide (polyamide 6), polyhexamethylene adipamide (polyamide 66), polyhexamethylene azamide (polyamide 69), polyhexamethylene sebacamide (polyamide 610), and polyhexamethylene dodecamide (polyamide 612). A raw material monomer forming at least one selected from the group as a main component, polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide 1010), polydecamethylene dodecamide (polyamide 1012), At least one raw material monomer that forms at least one selected from the group consisting of polydodecamethylene dodecamide (polyamide 1212), polyundecane amide (polyamide 11), and polydodecanamide (polyamide 12) The laminated tube according to claim 1, which is a copolymer of
[Claim 4]
　The mixing mass ratio of the terminal amino group concentration (μeq/g) and terminal carboxyl group concentration (μeq/g) of each of the polyamide (A1) and the polyamide (A2) per 1 g of the aliphatic polyamide composition (A) is shown. [A]>[B]+10, where [A] (µeq/g) is the terminal amino group concentration and [B] (µeq/g) is the terminal carboxyl group concentration, which are the sum of the multiplied values. The laminated tube according to any one of 1 to 3.
[Claim 5]
　5. At least one set of said adjacent (a) layer and (b) layer, wherein said (b) layer is arranged inwardly adjacent to said (a) layer. The laminated tube according to item 1.
[Claim 6]
　Further comprising (c) a layer,
　at least one pair of said (b) layer and the (c) layer is disposed adjacent,
　the (c) layer comprises a polyamide composition (C),
　the polyamide composition The substance (C) contains a polyamide (C1) and an elastomer polymer (C2), and the
　polyamide (C1) has a melting point of 210° C. or less measured according to ISO 11357-3 and a methylene group number of It is a polyamide other than the "aliphatic polyamide having a ratio to the number of amide groups of 8.0 or more", and is contained in an amount of 70% by mass or more and 95% by mass or less with respect to 100% by mass of the total of the polyamide (C1) and the elastomer polymer (C2). The
　elastomer polymer (C2) contains a structural unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group, and the total amount of the polyamide (C1) and the elastomer polymer (C2) is 100% by mass. On the other hand, the laminated tube according to any one of claims 1 to 5, which is contained in an amount of 5% by mass or more and 30% by mass or less.
[Claim 7]
　The laminated tube according to claim 6, wherein the (c) layer is disposed inside the (b) layer.
[Claim 8]
　Furthermore, it further comprises a
　(d) layer , the (d) layer comprises a semi-aromatic polyamide composition (D), and the
　semi-aromatic polyamide composition (D) comprises a semi-aromatic polyamide (D1) and/or a semi-aromatic polyamide composition. includes aromatic polyamide (D2),
　wherein in the semiaromatic polyamide composition (D), the semi-aromatic polyamide (D1) and / or the semi-aromatic polyamide (D2) is contained more than 60 wt%,
　the The semi-aromatic polyamide (D1) contains 50 mol% or more of an aliphatic diamine unit having 4 to 12 carbon atoms, based on all diamine units of the semi-aromatic polyamide (D1). 50 mol% or more of dicarboxylic acid units containing at least one selected from the group consisting of terephthalic acid units, isophthalic acid units, and naphthalenedicarboxylic acid units based on all dicarboxylic acid units of D1), and the
　semi-aromatic polyamide (D2) contains 50 mol% or more of a xylylenediamine unit and/or a bis(aminomethyl)naphthalene unit with respect to all diamine units of the semi-aromatic polyamide (D2), and the semi-aromatic polyamide (D2). The laminated tube according to any one of claims 1 to 7, which contains 50 mol% or more of an aliphatic dicarboxylic acid unit having 4 to 12 carbon atoms with respect to the total dicarboxylic acid unit.
[Claim 9]
　The semi-aromatic polyamide composition (D) contains an elastomer polymer (D3), and the elastomer polymer (D3) is a structural unit derived from an unsaturated compound having a carboxyl group and/or an acid anhydride group. The laminated tube according to claim 8, which comprises:
[Claim 10]
　The laminated tube according to claim 8 or 9, wherein the (d) layer is disposed inside the (a) layer.
[Claim 11]
　Furthermore, the (e) layer is included, The
　said (e) layer contains the fluorine-containing polymer (E) by which the functional group which has reactivity with an amino group was introduce|transduced into the molecular chain. The laminated tube according to any one of 1.
[Claim 12]
　The laminated tube according to claim 11, wherein the (e) layer is disposed inside the (a) layer.
[Claim 13]
　Furthermore,
　at least one set of the (d) layer and the (e) layer is disposed adjacent to
　each other, including the (e) layer, and the (e) layer has a functional group reactive with an amino group. The laminated tube according to any one of claims 8 to 10, which comprises a fluorine-containing polymer (E) introduced into a molecular chain.
[Claim 14]
　The laminated tube according to claim 13, wherein the (e) layer is disposed inside the (d) layer.
[Claim 15]
　The laminated tube according to any one of claims 1 to 14, wherein the innermost layer is a conductive layer containing a thermoplastic resin composition containing a conductive filler.
[Claim 16]
　The laminated tube according to any one of claims 1 to 15, which is manufactured by coextrusion molding.
[Claim 17]
　The laminated tube according to any one of claims 1 to 16, which is used as a fuel tube.