WO2023282154A1

WO2023282154A1 - Polyamide composition

Info

Publication number: WO2023282154A1
Application number: PCT/JP2022/026067
Authority: WO
Inventors: 健治關口
Original assignee: 株式会社クラレ
Priority date: 2021-07-08
Filing date: 2022-06-29
Publication date: 2023-01-12
Also published as: CN117396559A; JPWO2023282154A1

Abstract

Provided is a polyamide composition which comprises a polyamide, a polyolefin, and a copper-based stabilizer, wherein: the polyolefin contains at least one kind of polyolefin (A) that contains a copolymer of ethylene, alkyl (meth)acrylate, and an unsaturated epoxide and at least one kind of polyolefin (B) that contains an unsaturated dicarboxylic anhydride; the mass ratio [B]/[A] of the content [B] of the polyolefin (B) to the content [A] of the polyolefin (A) is 0.1-2.9; and the value Z calculated by formula (1) is 33-200. Also provided are a production method therefor, use thereof, and a molded body obtained therefrom.　Formula (1): Z=1000×(|[ANH]-[EPO]|+[EPO])/X² [EPO] is the concentration (mmol/kg) of the unsaturated epoxide, which is derived from the polyolefin, per unit mass of the composition.　[ANH] is the concentration (mmol/kg) of the unsaturated dicarboxylic anhydride, which is derived from the polyolefin, per unit mass of the composition.　The X is the content (mass%) of the polyolefin in the composition.

Description

Polyamide composition

The present invention relates to a polyamide composition that has excellent heat resistance and is also excellent in flexibility, impact resistance, processing stability, and whitening resistance.

Polyamide resin has excellent strength, heat resistance, chemical resistance, etc., and has been used for automobile mechanical parts such as fuel pipes and fuel pipe joints (connectors). For example, polyamide resin compositions are also used in tubes for circulating long-life coolants used for cooling automobile engines and refrigerants for cooling air conditioners. Aliphatic polyamides such as polyamide 12, polyamide 11, and polyamide 6 are widely used for the tube from the viewpoint of ease of extrusion molding and flexibility. On the other hand, problems such as insufficient chemical resistance and insufficient heat resistance have been pointed out for these aliphatic polyamides. Especially in recent years, with the aim of improving the fuel efficiency of automobiles, the use of resin for cooling water, high-temperature gas, and oil-flowing tubes has been actively studied. is desired.

Patent Document 1 discloses that a tube made of a semi-aromatic polyamide and a modified elastomer and having a specific phase separation structure exhibits excellent surface smoothness and flexibility. Moreover, it is said that the functional group concentration of the elastomer used for the tube is preferably within a specific range.

Patent Document 2 discloses a composition containing a semi-aromatic polyamide, a specific polyolefin and a plasticizer, and is shown to be excellent in flexibility, heat aging resistance, and impact resistance.

WO2020/175290 Japanese Patent Publication No. 2015-501341

It has long been known that blending a polyolefin containing a functional group that reacts with a polyamide to impart flexibility and impact resistance to the polyamide. At this time, by increasing the concentration of the functional group, the affinity of the polyolefin to the polyamide can be increased and the dispersibility can be improved. On the other hand, it has been pointed out that when the concentration of functional groups is lowered, the affinity of polyolefin to polyamide is lowered, resulting in deterioration of processability such as bleeding out of a part of polyolefin during melt kneading. In addition, it has been pointed out that when a molded article using a composition comprising a polyamide and a polyolefin is subjected to secondary processing, the surface of the molded article becomes white and the quality of the product deteriorates.
Therefore, the present invention provides a polyamide composition that has excellent heat resistance and is also excellent in flexibility, impact resistance, processing stability, and whitening resistance, a method for producing the same, use of the above polyamide composition, and the above polyamide composition An object of the present invention is to provide a molded body using an object.

As a result of intensive studies, the present inventors found that by melt-kneading a polyamide, a specific polyolefin, and a copper-based stabilizer, flexibility, impact resistance, processing stability, and whitening resistance can be achieved while maintaining excellent heat resistance. The present inventors have found that a polyamide composition having excellent properties can be obtained.

That is, the present invention is as follows.
[1] A composition comprising a polyamide, a polyolefin and a copper-based stabilizer,
The polyolefin contains at least one polyolefin (A) containing a copolymer of ethylene, an alkyl (meth)acrylate and an unsaturated epoxide, and at least one polyolefin (B) containing an unsaturated dicarboxylic acid anhydride, and The mass ratio [B]/[A] of the content [B] of the polyolefin (B) to the content [A] of the polyolefin (A) is 0.1 to 2.9,
A polyamide composition having a value Z of 33 to 200 calculated from the following formula (1).
Z = 1000 × (|[ANH]−[EPO]|+[EPO])/X ² formula (1)
The [EPO] is the concentration (mmol/kg) of unsaturated epoxide derived from the polyolefin per unit mass of the composition.
The [ANH] is the concentration (mmol/kg) of the unsaturated dicarboxylic anhydride derived from the polyolefin per unit mass of the composition.
The above X is the polyolefin content (% by mass) in the composition.
[2] The polyamide composition according to [1], wherein the polyamide contains at least one selected from terephthalic acid units and naphthalene dicarboxylic acid units in an amount of 50 mol% or more based on all dicarboxylic acid units.
[3] The above [1] or [2], wherein the polyamide contains 60 mol% or more of aliphatic diamine units having 4 to 13 carbon atoms or meta-xylylenediamine units based on all diamine units. of the polyamide composition.
[4] The aliphatic diamine units are 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1, The polyamide composition according to [3], wherein the unit is derived from at least one aliphatic diamine selected from the group consisting of 10-decanediamine.
[5] The above [3] or [4], wherein the aliphatic diamine unit is a unit derived from at least one aliphatic diamine selected from 1,9-nonanediamine and 2-methyl-1,8-octanediamine. ] Polyamide composition according to.
[6] The polydispersity index of the polyamide measured by gel permeation chromatography is 3.7 or more, the content of terminal amino groups in the polyamide is 10 to 70 µeq/g, and the content of terminal carboxyl groups in the polyamide is 10. The polyamide composition according to any one of the above [1] to [5], which is ~70 μeq/g.
[7] The polyamide composition according to any one of [1] to [6], wherein the polyolefin content is 14 to 40% by mass.
[8] The polyamide composition according to any one of [1] to [7], wherein the polyolefin content is 15 to 30% by mass.
[9] The polyamide composition according to any one of [1] to [8], wherein the polyolefin (B) is a copolymer of ethylene, an alkyl (meth)acrylate and an unsaturated dicarboxylic acid anhydride.
[10] The polyamide composition according to any one of [1] to [9], wherein the content of the copper-based stabilizer is 0.01 to 2% by mass.
[11] The copper-based stabilizer comprises at least one copper compound selected from the group consisting of copper iodide, copper bromide, and copper acetate, and at least one selected from the group consisting of potassium iodide and potassium bromide. The polyamide composition according to any one of the above [1] to [10], which contains a metal halide.
[12] Selected from the group consisting of polymers other than the polyamide and the polyolefin, antioxidants, fillers, crystal nucleating agents, colorants, antistatic agents, plasticizers, lubricants, flame retardants, and flame retardant aids The polyamide composition according to any one of [1] to [11] above, comprising at least one additive.
[13] A method for producing a polyamide composition according to any one of [1] to [12],
A method for producing a polyamide composition, wherein the polyamide, the polyolefin, and the copper-based stabilizer are top-fed to a twin-screw extruder and melt-kneaded.
[14] Use of the polyamide composition according to any one of [1] to [12] for producing a single layer structure or for producing at least one layer of a multilayer structure.
[15] A molded article made of the polyamide composition according to any one of [1] to [12].
[16] The molded article according to the above [15], which is an extruded article, a co-extruded article or a blow molded article.
[17] Fuel tubes, engine coolant tubes, battery coolant tubes, motor coolant tubes, fuel cell cooling tubes, urea solution delivery tubes, air conditioner coolant tubes, blow-by tubes, brake booster tubes, brake tubes, oil cooling tubes, The formed article according to [16] above, which is a turbo duct pipe, an air suspension tube, or an oil transportation tube.

According to the present invention, a polyamide composition having excellent heat resistance, flexibility, impact resistance, processing stability, and whitening resistance, a method for producing the same, use of the above polyamide composition, and the above polyamide A molded article using the composition can be provided.

Further features, forms and advantages of the present invention will become clearer upon reading the detailed description and examples below.

Also, preferred forms of embodiments are indicated herein, and combinations of two or more of the individual preferred forms are also preferred forms. When there are several numerical ranges for items indicated by numerical ranges, the lower and upper limits thereof can be selectively combined to form a preferred form. For example, the description “XX to YY” means “XX or more and YY or less”. In addition, "- unit" (where "-" indicates a monomer) means "a structural unit derived from". For example, a "dicarboxylic acid unit" means a "structural unit derived from a dicarboxylic acid". A "diamine unit" means a "structural unit derived from a diamine". In addition, "(meth)acrylate" means "acrylate" and "methacrylate" corresponding thereto.
Also, "tube" means a cylindrical structure such as a pipe or hose.

<Polyamide composition>
[polyamide]
The polyamide composition of this embodiment comprises at least one polyamide.

The above polyamide contains at least one repeating unit consisting of polycondensation of dicarboxylic acid units and diamine units.

Dicarboxylic acid units include terephthalic acid units, naphthalenedicarboxylic acid units, isophthalic acid units, 1,4-phenylenedioxydiacetic acid units, 1,3-phenylenedioxydiacetic acid units, diphenic acid units, and diphenylmethane-4,4. Aromatic dicarboxylic acid units such as '-dicarboxylic acid units, diphenylsulfone-4,4'-dicarboxylic acid units and 4,4'-biphenyldicarboxylic acid units are included.
Examples of the naphthalenedicarboxylic acid unit include units derived from 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and 1,4-naphthalenedicarboxylic acid, and 2,6-naphthalenedicarboxylic acid unit is preferred. .
Dicarboxylic acid units include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, dimethylmalonic acid, and 2,2-diethyl. Aliphatic dicarboxylic acids such as succinic acid, 2,2-dimethylglutaric acid, 2-methyladipic acid, trimethyladipic acid, dimer acid; 1,3-cyclopentanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4 - units derived from alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, cycloheptanedicarboxylic acid, cyclooctanedicarboxylic acid and cyclodecanedicarboxylic acid.
Only one kind of units derived from these dicarboxylic acids may be contained, or two or more kinds thereof may be contained.

The polyamide used in the present invention preferably contains 50 mol% or more of at least one selected from terephthalic acid units and naphthalenedicarboxylic acid units based on all dicarboxylic acid units. Further, from the viewpoint of becoming a polyamide having good chemical resistance and heat resistance, the polyamide used in the present invention contains 75 mol% or more of at least one selected from terephthalic acid units and naphthalene dicarboxylic acid units with respect to all dicarboxylic acid units. More preferably, it contains 90 mol % or more.

Diamine units include ethylenediamine, 1,2-propanediamine, 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 and other linear aliphatic diamines;2 -methyl-1,3-propanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4 ,4-trimethyl-1,6-hexanediamine, 2-methyl-1,8-octanediamine, 5-methyl-1,9-nonanediamine and other branched aliphatic diamines; cyclohexanediamine, methylcyclohexanediamine, isophoronediamine alicyclic diamines such as p-phenylenediamine, m-phenylenediamine, xylylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenyl ether and other aromatic diamines and the like.
Only one type of unit derived from these diamines may be contained, or two or more types thereof may be contained.

The polyamide used in the present invention preferably contains 60 mol % or more of aliphatic diamine units having 4 to 13 carbon atoms or meta-xylylenediamine units based on all diamine units. By using a polyamide containing aliphatic diamine units having 4 to 13 carbon atoms in the above ratio, a polyamide composition having excellent toughness, heat resistance, chemical resistance and lightness can be obtained. The polyamide used in the present invention preferably contains 75 mol% or more, more preferably 90 mol% or more, of at least one selected from aliphatic diamine units having 4 to 13 carbon atoms with respect to all diamine units. .

The aliphatic diamine units having 4 to 13 carbon atoms are 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,9-nonanediamine, 2-methyl-1,8-octane Units derived from at least one aliphatic diamine selected from the group consisting of diamines and 1,10-decanediamine are more preferred. Since a polyamide composition having even better heat resistance, low water absorption and chemical resistance can be obtained, the aliphatic diamine units having 4 to 13 carbon atoms are 1,9-nonanediamine and 2-methyl-1,8- Units derived from at least one aliphatic diamine selected from octanediamine are more preferred, and 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units are more preferred.
When the aliphatic diamine units contain both units derived from 1,9-nonanediamine and 2-methyl-1,8-octanediamine, 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units is preferably in the range of 1,9-nonanediamine unit/2-methyl-1,8-octanediamine unit = 95/5 to 40/60, and in the range of 90/10 to 40/60. is more preferable, and more preferably in the range of 80/20 to 40/60.

The polyamide used in the present invention may contain aminocarboxylic acid units and/or lactam units.
Examples of the aminocarboxylic acid unit include units derived from 11-aminoundecanoic acid, 12-aminododecanoic acid, and the like. Two or more aminocarboxylic acid units may be included. The content of aminocarboxylic acid units in the polyamide is preferably 50 mol% or less, more preferably 20 mol% or less, and 10 mol% or less with respect to 100 mol% of the total monomer units constituting the polyamide. is more preferable.

Examples of the lactam unit include units derived from ε-caprolactam, enantholactam, undecanelactam, lauryllactam, α-pyrrolidone, α-piperidone, etc. Two or more types of lactam units are included. good too. The content of the lactam unit in the polyamide is preferably 50 mol% or less, more preferably 20 mol% or less, and 10 mol% or less with respect to 100 mol% of the total monomer units constituting the polyamide. is more preferred.

In this embodiment, the polyamide is a semi-aromatic polyamide containing dicarboxylic acid units mainly composed of aromatic dicarboxylic acid units and diamine units mainly composed of aliphatic diamine units having 4 to 13 carbon atoms. is preferred.
In the present specification, the term "mainly composed" means to constitute 50 to 100 mol%, preferably 60 to 100 mol%, more preferably 80 to 100 mol% of the total units.
Typical semi-aromatic polyamides include polytetramethylene terephthalamide (polyamide 4T), polypentamethylene terephthalamide (polyamide 5T), polyhexamethylene terephthalamide (polyamide 6T), polynonamethylene terephthalamide (polyamide 9T), poly(2-methyloctamethylene)terephthalamide (nylon M8T), polynonamethyleneterephthalamide/poly(2-methyloctamethylene)terephthalamide copolymer (polyamide 9T/M8T), polynonamethylenenaphthalene dicarboxamide (polyamide 9N), Polynonamethylene naphthalene dicarboxamide/poly(2-methyloctamethylene) naphthalene dicarboxamide copolymer (polyamide 9N/M8N), polydecamethylene terephthalamide (polyamide 10T), polyhexamethylene isophthalamide (polyamide 6I), polyamide 6I and polyamide 6T copolymer (polyamide 6I/6T), polyamide 6T and polyundecaneamide (polyamide 11) copolymer (polyamide 6T/11), and polyamide 10T and polyundecaneamide (polyamide 11) copolymer coalescence (polyamide 10T/11);
Among these, polyamide 10T/11, polynonamethylenenaphthalenedicarboxamide (polyamide 9N), polynonamethylenenaphthalenedicarboxamide/poly(2-methyloctamethylene)naphthalene dicarboxamide copolymer (polyamide 9N/M8N), polynonamethylene terephthalate At least one selected from amide (polyamide 9T), polynonamethylene terephthalamide/poly(2-methyloctamethylene) terephthalamide copolymer (polyamide 9T/M8T) and polydecamethylene terephthalamide (polyamide 10T) is preferred, and polynona Methylenenaphthalene dicarboxamide/poly(2-methyloctamethylene)naphthalene dicarboxamide copolymer (polyamide 9N/M8N), polynonamethylene terephthalamide/poly(2-methyloctamethylene) terephthalamide copolymer (polyamide 9T/M8T), and polyamide At least one selected from 10T/11 is more preferable, and from the viewpoint of ensuring moldability and rigidity at high temperatures, polynonamethylene terephthalamide/poly(2-methyloctamethylene) terephthalamide copolymer (polyamide 9T/M8T ) is more preferred.

As the polyamide, a semi-aromatic polyamide containing dicarboxylic acid units mainly composed of aliphatic dicarboxylic acid units and diamine units mainly composed of aromatic diamine units can be used. Examples of the aliphatic dicarboxylic acid unit include units derived from the aforementioned aliphatic dicarboxylic acids, and one or more of these may be included. In addition, the aromatic diamine unit may include units derived from the aromatic diamine described above, and one or more of these may be included. Also, other units may be included within the range that does not impair the effects of the present invention.
Typical semi-aromatic polyamides containing dicarboxylic acid units mainly composed of aliphatic dicarboxylic acid units and diamine units mainly composed of aromatic diamine units include polymetaxylylene adipamide (MXD6), poly paraxylylene sebacamide (PXD10) and the like.

Moreover, an aliphatic polyamide can also be used as polyamide.
Aliphatic polyamides include polycaproamide (polyamide 6), polyundecaneamide (polyamide 11), polydodecanamide (polyamide 12), polytetramethylene adipamide (polyamide 46), polyhexamethylene adipamide (polyamide 66 ), polynonamethylene oxide (polyamide 92), polyhexamethylene sebacamide (polyamide 610), polyhexamethylene dodecamide (polyamide 612), polynonamethylene sebacamide (polyamide 910), polynonamethylene dodecamide (polyamide 912), polydecamethylene sebacamide (polyamide 1010), polydecamethylene dodecamide (polyamide 1012), polydodecamethylene sebacamide (polyamide 1210), polydodecamethylene dodecamide (polyamide 1212), and the like.

In the polyamide used in the present invention, 10 mol% or more of all the terminal groups of the molecular chains are preferably blocked with a terminal blocking agent. When a polyamide having a terminal capping rate of 10 mol % or more is used, a polyamide composition having better physical properties such as melt stability and hot water resistance can be obtained.

A monofunctional compound having reactivity with a terminal amino group or a terminal carboxyl group can be used as the terminal blocking agent. Specific examples include monocarboxylic acids, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, and monoamines. From the viewpoint of reactivity and stability of the terminal to be blocked, monocarboxylic acid is preferable as the terminal blocking agent for the terminal amino group, and monoamine is preferable as the terminal blocking agent for the terminal carboxyl group. From the standpoint of ease of handling, etc., monocarboxylic acids are more preferable as terminal blocking agents.

The monocarboxylic acid used as the terminal blocking agent is not particularly limited as long as it has reactivity with amino groups. Examples of monocarboxylic acids include aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid. cyclopentanecarboxylic acid, cyclohexanecarboxylic acid and other alicyclic monocarboxylic acids; benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, phenylacetic acid and other aromatic monocarboxylic acids and any mixture thereof. Among these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, and stearic acid are preferred in terms of reactivity, stability of blocked ends, and price. , and benzoic acid are preferred.

The monoamine used as the terminal blocking agent is not particularly limited as long as it has reactivity with the carboxyl group. Examples of monoamines include aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine and dibutylamine; alicyclic monoamines; aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine; arbitrary mixtures thereof; Among these, at least one selected from butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline is preferable from the viewpoints of reactivity, high boiling point, stability of capped ends, price, and the like.

The polyamide used in the present invention preferably has an intrinsic viscosity [η _inh ] of 0.6 dl/g or more, measured at a concentration of 0.2 g/dl and a temperature of 30° C. using concentrated sulfuric acid as a solvent, and preferably 0.8 dl/g. It is more preferably 1.0 dl/g or more, more preferably 1.0 dl/g or more. The intrinsic viscosity is preferably 2.0 dl/g or less, more preferably 1.8 dl/g or less, and even more preferably 1.6 dl/g or less. When the intrinsic viscosity [η _inh ] of the polyamide is within the above range, various physical properties such as moldability are further improved. The intrinsic viscosity [η _inh ] is determined by the flowing time t ₀ (seconds) of the solvent (concentrated sulfuric acid), the flowing time t ₁ (seconds) of the sample solution, and the sample concentration c (g/dl) in the sample solution (i.e., 0.2 g /dl) by the relational expression η _inh =[ln(t ₁ /t ₀ )]/c.

The polyamide used in the present invention preferably has a terminal amino group content (hereinafter also referred to as “terminal amino group content”) ([NH ₂ ]) of 10 to 70 μeq/g, more preferably 10 to 65 μeq/g. more preferably 10 to 60 μeq/g. If the terminal amino group content ([NH ₂ ]) is 10 µeq/g or more, the compatibility between the polyamide and the later-described polyolefin is good. Further, when the terminal amino group content is 70 μeq/g or less, when a modified polyolefin described later is used as the polyolefin, it is possible to avoid the progress of gelation due to excessive reaction between the terminal amino group and the modified portion of the polyolefin. .
The terminal amino group content ([NH ₂ ]) as used herein refers to the amount of terminal amino groups contained in 1 g of the polyamide (unit: μeq), and can be determined by a neutralization titration method using an indicator. .

The polyamide used in the present invention preferably has a terminal carboxyl group content (hereinafter also referred to as "terminal carboxyl group content") ([COOH]) of 10 to 70 µeq/g, and 12 to 65 µeq/g. is more preferable, and 14 to 60 μeq/g is even more preferable. If the terminal carboxyl group content ([COOH]) is 10 µeq/g or more, the compatibility between the polyamide and the later-described polyolefin is good. In addition, if the terminal carboxyl group content is 70 μeq/g or less, when a modified polyolefin described later is used as the polyolefin, it is possible to avoid the progress of gelation due to excessive reaction between the terminal carboxyl group and the modified portion of the polyolefin. .
The terminal carboxyl group content ([COOH]) as used herein refers to the amount of terminal carboxyl groups contained in 1 g of the polyamide (unit: μeq), and can be determined by a neutralization titration method using an indicator.

A polyamide containing a dicarboxylic acid unit and a diamine unit and having a terminal amino group content ([NH ₂ ]) and a terminal carboxyl group content ([COOH]) within the ranges described above can be produced, for example, as follows.
First, a dicarboxylic acid, a diamine, and optionally an aminocarboxylic acid, a lactam, a catalyst and a terminal blocking agent are mixed to produce a nylon salt. At this time, the number of moles (X) of all carboxyl groups and the number of moles (Y) of all amino groups contained in the above reaction raw materials are calculated by the following formula (Q)
-0.5 ≤ [(YX) / Y] × 100 ≤ 2.0 Formula (Q)
is satisfied, it is easy to produce a polyamide having a terminal amino group content ([NH ₂ ]) and a terminal carboxyl group content ([COOH]) of 10 to 70 μeq/g, which is preferable. Next, the produced nylon salt is heated to a temperature of 200 to 250° C. to obtain a prepolymer having an intrinsic viscosity [η _inh ] of 0.10 to 0.60 dl/g at 30° C. in concentrated sulfuric acid, and further to a high degree of polymerization. By doing so, a polyamide can be obtained. When the intrinsic viscosity [η _inh ] of the prepolymer is within the range of 0.10 to 0.60 dl/g, the deviation of the molar balance between the carboxyl groups and the amino groups and the decrease in the polymerization rate are small in the stage of increasing the degree of polymerization. Furthermore, a polyamide with a narrow molecular weight distribution and excellent various performances and moldability can be obtained. When the step of increasing the degree of polymerization is performed by a solid phase polymerization method, it is preferably performed under reduced pressure or under an inert gas flow. and can effectively suppress coloring and gelation. Further, when the step of increasing the degree of polymerization is performed by a melt extruder, the polymerization temperature is preferably 370 ° C. or less, and when polymerization is performed under such conditions, there is almost no decomposition of the polyamide, and a polyamide with little deterioration can be obtained. .

<Polyamide content>
The content of the polyamide contained in the polyamide composition of the present embodiment is preferably 60 to 86% by mass with respect to 100% by mass of the polyamide composition, more preferably 65 to 86% by mass, 70 to It is more preferably 86% by mass, and even more preferably 70 to 80% by mass. When the content of the polyamide is within the above range, it is possible to obtain a polyamide composition which is more excellent in heat resistance, processing stability during melt-kneading, flexibility, and impact resistance.

<Polydispersity index>
The polydispersity index Mw/Mn (Mw is the weight average molecular weight, Mn is the number average molecular weight) of the polyamide contained in the polyamide composition of the present embodiment is preferably 3.7 or more, and preferably 4.0 or more. may If the polydispersity index is 3.7 or more, a composition having excellent melt tension during extrusion molding can be obtained. Moreover, the polydispersity index Mw/Mn of the polyamide is preferably 8.0 or less. If the polydispersity index is 8.0 or less, a composition having excellent fluidity during extrusion molding can be obtained.
Polydispersity index of polyamide can be measured by gel permeation chromatography, more specifically, it is a value measured by the method described in Examples.

Catalysts that can be used in producing polyamides include, for example, phosphoric acid, phosphorous acid, hypophosphorous acid, or salts or esters thereof. Examples of the above salts or esters include phosphoric acid, phosphorous acid, or hypophosphorous acid and potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin, tungsten, germanium, titanium, antimony, and the like. Salt with metal; Ammonium salt of phosphoric acid, phosphorous acid or hypophosphite; Ethyl ester, isopropyl ester, butyl ester, hexyl ester, isodecyl ester, octadecyl ester of phosphoric acid, phosphorous acid or hypophosphorous acid , decyl ester, stearyl ester, phenyl ester, and the like.
The amount of the catalyst used is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and 1.0% by mass or less with respect to 100% by mass of the total mass of the raw materials. and more preferably 0.5% by mass or less. If the amount of the catalyst used is at least the above lower limit, the polymerization proceeds satisfactorily. If the content is not more than the above upper limit, catalyst-derived impurities are less likely to occur, and for example, problems due to the above impurities can be prevented when the polyamide composition is extruded.

[Polyolefin]
The polyamide composition of this embodiment comprises a polyamide and a polyolefin, the polyolefin being present as a dispersed phase in the matrix polyamide.
The polyolefin contains at least one polyolefin (A) containing a copolymer of ethylene, an alkyl (meth)acrylate and an unsaturated epoxide, and at least one polyolefin (B) containing an unsaturated dicarboxylic acid anhydride.
The total content of polyolefin (A) and polyolefin (B) contained in polyolefin is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, and substantially 100% by mass. good too.

<Polyolefin (A)>
Polyolefin (A) includes a copolymer of ethylene, alkyl (meth)acrylate and unsaturated epoxide. Moreover, from the viewpoint of avoiding gelation due to intramolecular reaction, it is desirable that the polyolefin (A) does not contain an unsaturated dicarboxylic acid anhydride.

The unsaturated epoxides include aliphatic glycidyl ethers and esters such as allyl glycidyl ether, vinyl glycidyl ether, glycidyl maleate and itaconate, glycidyl acrylate and methacrylate; 5-dicarboxylate, glycidylcyclohexene-4-carboxylate, glycidyl 5-norbornene-2-methyl-2-carboxylate and diglycidyl endo-cis-bicyclo[2.2.1]hept-5-ene-2, epoxides such as cycloaliphatic glycidyl ethers and esters such as 3-dicarboxylate;

The alkyl (meth)acrylate preferably contains 2 to 10 carbon atoms.
Alkyl (meth)acrylates include methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate and 2-ethylhexyl acrylate.

Particularly preferred examples of polyolefin (A) include copolymers of ethylene, methyl acrylate and glycidyl methacrylate, and copolymers of ethylene, butyl acrylate and glycidyl methacrylate. Commercially available products can also be used as the polyolefin (A). For example, Lotader AX8900, Lotader AX8750, and Lotader AX8390 sold by SK global chemical can be used.

<Polyolefin (B)>
Polyolefin (B) is a polymer containing an unsaturated dicarboxylic acid anhydride. The unsaturated dicarboxylic anhydride has been introduced into the polymer either by grafting or copolymerization. Moreover, from the viewpoint of avoiding gelation due to intramolecular reaction, it is desirable that the polyolefin (B) does not contain an unsaturated epoxide.

Examples of unsaturated dicarboxylic anhydrides include in particular maleic anhydride, itaconic anhydride, citraconic anhydride and tetrahydrophthalic anhydride.

Examples of polyolefin (B) include α-olefin copolymers, (ethylene and/or propylene)/(α,β-unsaturated carboxylic acid and/or unsaturated carboxylic acid ester) copolymers, ionomers, Alternatively, a modified polyolefin obtained by modifying an aromatic vinyl compound/conjugated diene compound block copolymer (hereinafter sometimes referred to as "copolymer, etc.") with an unsaturated dicarboxylic acid anhydride can be used.
The above copolymers and the like can be used singly or in combination of two or more.

Examples of the α-olefin copolymers include copolymers of ethylene and α-olefins having 3 or more carbon atoms and copolymers of propylene and α-olefins having 4 or more carbon atoms.
Examples of α-olefins having 3 or more carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, and 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, and 12-ethyl-1-tetradecene. These can use 1 type(s) or 2 or more types.

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-vinylnorbornene, 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, 2-propenyl-2,5-norbornadiene; Polyenes may be copolymerized. These can use 1 type(s) or 2 or more types.

The (ethylene and/or propylene)/(α,β-unsaturated carboxylic acid and/or unsaturated carboxylic acid ester) copolymer is composed of ethylene and/or propylene and α,β-unsaturated carboxylic acid and/or It is a polymer obtained by copolymerizing an unsaturated carboxylic acid ester. Examples of the α,β-unsaturated carboxylic acid include acrylic acid and methacrylic acid. Examples of the α,β-unsaturated carboxylic acid esters include methyl esters, ethyl esters, propyl esters, butyl esters, pentyl esters, hexyl esters, heptyl esters, octyl esters, nonyl esters and decyl esters of the above unsaturated carboxylic acids. etc. These can use 1 type(s) or 2 or more types.

The ionomer is a copolymer of an olefin and an α,β-unsaturated carboxylic acid in which at least part of the carboxyl groups are ionized by neutralization with metal ions. Ethylene is preferably used as the olefin, and acrylic acid and methacrylic acid are preferably used as the α,β-unsaturated carboxylic acid, but they are not limited to those exemplified here. The copolymer of the olefin and the α,β-unsaturated carboxylic acid may be further copolymerized with an unsaturated carboxylic acid ester as a monomer. In addition, metal ions include Al, Sn, Sb, Ti, Mn, Fe, Ni, Cu, Zn, Cd, etc., in addition to alkali metals such as Li, Na, K, Mg, Ca, Sr, and Ba, and alkaline earth metals. is mentioned. These can use 1 type(s) or 2 or more types.

The above-mentioned aromatic vinyl compound/conjugated diene compound block copolymer is a block copolymer comprising an aromatic vinyl compound polymer block and a conjugated diene polymer block. A block copolymer having one and at least one conjugated diene polymer block is used. In the above block copolymer, the unsaturated bond in the conjugated diene polymer block may be hydrogenated.

The aromatic vinyl compound-based polymer block is a polymer block mainly composed of structural units derived from aromatic vinyl compounds. Examples of aromatic vinyl compounds in that case include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, vinylnaphthalene, vinylanthracene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl)styrene and the like can be mentioned, and one or more of these can be used. In addition, the aromatic vinyl compound-based polymer block may optionally have a structural unit composed of a small amount of other unsaturated monomer. The conjugated diene-based polymer block includes conjugated butadiene, chloroprene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 4-methyl-1,3-pentadiene, 1,3-hexadiene, and the like. It is a polymer block formed from one or more diene compounds. In the hydrogenated aromatic vinyl compound/conjugated diene compound block copolymer, part or all of the unsaturated bond portions in the conjugated diene polymer block are hydrogenated.

The molecular structure of the aromatic vinyl compound/conjugated diene compound block copolymer and its hydrogenated product may be linear, branched, radial, or any combination thereof. Among these, as the aromatic vinyl compound/conjugated diene compound block copolymer and/or its hydrogenated product, one aromatic vinyl compound polymer block and one conjugated diene polymer block are linear A diblock copolymer in which three polymer blocks are linked linearly in the order of aromatic vinyl compound polymer block - conjugated diene polymer block - aromatic vinyl compound polymer block. One or more of triblock copolymers and hydrogenated products thereof are preferably used. Aromatic vinyl compound/conjugated diene compound block copolymers and hydrogenated products thereof include, for example, unhydrogenated or hydrogenated styrene/butadiene block copolymers, unhydrogenated or hydrogenated styrene/isoprene block copolymers, Unhydrogenated or hydrogenated styrene/isoprene/styrene block copolymer, Unhydrogenated or hydrogenated styrene/butadiene/styrene block copolymer, Unhydrogenated or hydrogenated styrene/isoprene/butadiene/styrene block copolymer, etc. is mentioned.

Polyolefin (B) is preferably a copolymer of ethylene, alkyl (meth)acrylate and unsaturated dicarboxylic acid anhydride.
Alkyl (meth)acrylates preferably contain from 2 to 10 carbon atoms. Alkyl (meth)acrylates include methyl acrylate, methyl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate and 2-ethylhexyl acrylate.

Among the above polyolefins (B), more preferable examples include copolymers of ethylene, ethyl acrylate and maleic anhydride, and copolymers of ethylene, butyl acrylate and maleic anhydride. Commercially available products can also be used as the polyolefin (B). For example, Lotader 4700 and Lotader 3410 sold by SK global chemical can be used.

Further, even if part of the maleic anhydride exemplified as the unsaturated dicarboxylic acid anhydride in the polyolefin (B) is partially hydrolyzed, it does not depart from the scope of the present invention.

<Mass ratio [B]/[A]>
The mass ratio [B]/[A] of the content [B] of the polyolefin (B) to the content [A] of the polyolefin (A) is 0.1 to 2.9, preferably 0.2 to 2. .9, more preferably 0.4 to 2.9, more preferably 0.5 to 2.9. If the mass ratio [B]/[A] is less than 0.1, the melt viscosity tends to increase and the moldability tends to deteriorate. If the mass ratio [B]/[A] exceeds 2.9, it tends to be difficult to achieve both stability during melt kneading and excellent elongation properties.

<Polyolefin content>
The content of the polyolefin contained in the polyamide composition of the present embodiment is preferably 14 to 40% by mass with respect to 100% by mass of the polyamide composition, more preferably 15 to 40% by mass, 15 to It is more preferably 35% by mass, and even more preferably 15 to 30% by mass. When the polyolefin content is within the above range, a polyamide composition having excellent processing stability, flexibility and impact resistance during melt-kneading can be obtained.

From the viewpoint of improving the flexibility of the molded article made of the polyamide composition of this embodiment, the polyolefin content is measured under the conditions of 23° C. and 50% RH according to ISO 178 (4th edition, 2001). The bending elastic modulus of the molded body of the polyamide composition is preferably adjusted to 2.0 GPa or less, more preferably 1.7 GPa or less, and adjusted to 1.5 GPa or less. more preferably.

<Functional group concentration>
The polyamide composition of this embodiment has a value Z calculated from the following formula (1) of 33-200, preferably 33-150. The value of Z may be 35-130. If the value of Z is less than 33, the affinity between the polyamide and the polyolefin may be insufficient, and the stability during melt kneading may be lowered. If the value of Z exceeds 200, the melt viscosity increases, which may make molding difficult, or the flexibility and impact resistance may be insufficient.
In this specification, the "functional group" in the "functional group concentration" refers to the epoxy group possessed by the polyolefin-derived unsaturated epoxide, and the polyolefin-derived unsaturated dicarboxylic acid anhydride possessed by the carboxyl group and acid means an anhydride group. And "functional group concentration" means the following [EPO] and [ANH].

formula (1)
Z=1000×(|[ANH]−[EPO]|+[EPO])/X ²
In the above formula (1), [EPO], [ANH] and X are as follows.
[EPO]: Concentration of unsaturated epoxide derived from polyolefin per unit mass of polyamide composition (mmol/kg).
[ANH]: Concentration of unsaturated dicarboxylic acid anhydride derived from polyolefin per unit mass of polyamide composition (mmol/kg).
X: Polyolefin content (% by mass) in the polyamide composition.

The unsaturated epoxide concentration [EPO] and the unsaturated dicarboxylic acid concentration [ANH] in the above formula (1) are calculated according to the following formula (2).
formula (2)
[EPO] or [ANH] = 100 x N x W/M
In the above formula (2), M, W and N are as follows.
M: Molecular weight of unsaturated epoxide or unsaturated dicarboxylic acid anhydride.
W: % by mass of unsaturated epoxide or unsaturated dicarboxylic acid anhydride contained in polyolefin (A) or polyolefin (B). W can be measured by a method common to those skilled in the art, such as NMR.
N: Mass % of polyolefin (A) or polyolefin (B) per unit mass of polyamide composition.

The above value of Z predicts the melt stability of the resulting polyamide composition when melt-kneading the polyamide, the polyolefin having an unsaturated epoxide, and the polyolefin having an unsaturated dicarboxylic acid anhydride. It is useful for obtaining a polyamide composition which is excellent in stability, flexibility and impact resistance. Unsaturated epoxides and unsaturated dicarboxylic acid anhydrides each react with polyamide to exhibit a compatibilizing effect, but since the above functional groups can react with each other, the remaining amount of functional groups available for reaction with polyamide is The difference between the two (|[ANH]−[EPO]|) is considered to be relevant. However, the two do not react completely, and the unsaturated epoxide is highly reactive in that it can react with both the terminal amino group and the terminal carboxyl group of the polyamide. The meaning numerator term is weighted by the unsaturated epoxide concentration. In addition, since the melt stability of the polyamide composition generally tends to decrease as the blending amount of polyolefin increases, the polyolefin content X is placed in the denominator.

The unsaturated epoxide concentration and the unsaturated dicarboxylic anhydride concentration in the polyamide composition are such that the terminal amino group, carboxyl group, unsaturated epoxide and unsaturated dicarboxylic anhydride of the polyamide react with each other during the melt-kneading process. difficult to identify. Therefore, the value of Z is calculated based on the amount of each component used in the polyamide composition.

[Copper-based stabilizer]
The polyamide composition of this embodiment contains at least one copper-based stabilizer to improve heat aging resistance.

The content of the copper-based stabilizer is preferably 0.01 to 2% by mass, more preferably 0.1 to 1.5% by mass, and 0.5 to 1.2% by mass with respect to 100% by mass of the polyamide composition. is even more preferred. When the content of the copper-based stabilizer is within the above range, it is possible to obtain a polyamide composition which is excellent in heat aging resistance and which generates a small amount of gas during extrusion molding.

A copper-based stabilizer can be used as a mixture of a copper compound and a metal halide. Regarding the ratio of the copper compound and the metal halide in the polyamide composition, the ratio of the total molar amount of halogen atoms to the total molar amount of copper atoms (halogen/copper) is 2/1 to 50/1, Preferably, the polyamide composition contains a copper compound and a metal halide. The ratio (halogen/copper) is preferably 3/1 or more, more preferably 4/1 or more, and still more preferably 5/1 or more. The ratio (halogen/copper) is preferably 45/1 or less, more preferably 40/1 or less, and even more preferably 30/1 or less. When the ratio (halogen/copper) is at least the above lower limit, copper deposition and metal corrosion during molding can be more effectively suppressed. When the ratio (halogen/copper) is equal to or less than the above upper limit, it is possible to more effectively suppress corrosion of screws of molding machines without impairing mechanical properties such as tensile properties of the resulting polyamide composition. .

Examples of copper compounds include copper halides, copper acetate, copper propionate, copper benzoate, copper adipate, copper terephthalate, copper isophthalate, copper salicylate, copper nicotinate, copper stearate, ethylenediamine and ethylenediaminetetraacetic acid. and a copper complex coordinated with a chelating agent. Examples of the copper halide include copper iodide; copper bromides such as cuprous bromide and cupric bromide; copper chlorides such as cuprous chloride. Among these copper compounds, at least one selected from the group consisting of copper halides and copper acetates is preferable from the viewpoint of excellent heat aging resistance and ability to suppress metal corrosion of screw and cylinder parts during extrusion. At least one selected from the group consisting of copper iodide, copper bromide, copper chloride, and copper acetate is more preferred, and at least one selected from the group consisting of copper iodide, copper bromide, and copper acetate is more preferred. . A copper compound may be used individually by 1 type, and may use 2 or more types together.

As the metal halide, a metal halide that does not correspond to a copper compound can be used, and a salt of a Group 1 or Group 2 metal element of the periodic table and a halogen is preferable. Examples of metal halides include potassium iodide, potassium bromide, potassium chloride, sodium iodide, sodium chloride and the like. Among these, at least one selected from the group consisting of potassium iodide and potassium bromide from the viewpoint that the obtained polyamide composition is excellent in high-temperature heat resistance such as heat aging resistance and can suppress metal corrosion. Preferred is potassium iodide. A metal halide may be used individually by 1 type, and may use 2 or more types together.
Among the copper compounds and metal halides, the copper-based stabilizer is at least one copper compound selected from the group consisting of copper iodide, copper bromide, and copper acetate, and the group consisting of potassium iodide and potassium bromide. It preferably contains at least one metal halide selected from the above.

A dispersant may be used to enhance the dispersibility of the copper compound and metal halide in the polyamide. Examples of the dispersant include higher fatty acids such as lauric acid, palmitic acid, stearic acid, behenic acid and montanic acid; higher fatty acid metal salts composed of higher fatty acids and metals such as aluminum; higher fatty acids such as ethylenebisstearylamide. amides; waxes such as polyethylene wax; organic compounds having at least one amide group;

[Other Additives]
The polyamide composition of this embodiment may optionally contain other additives in addition to the polyamide, polyolefin and copper-based stabilizer described above.

Other additives include polymers other than the above polyamides and polyolefins, antioxidants, fillers, crystal nucleating agents, colorants, antistatic agents, plasticizers, lubricants, flame retardants, flame retardant aids, and the like. be done. These other additives may be used singly or in combination of two or more.

Examples of other types of polymers include polyether resins such as polyacetal and polyphenylene oxide; polysulfone resins such as polysulfone and polyethersulfone; polythioether resins such as polyphenylene sulfide and polythioethersulfone; polyetheretherketone and polyaryletherketone. polyketone-based resins such as; polyacrylonitrile, polymethacrylonitrile, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, methacrylonitrile-butadiene-styrene copolymer and other polynitrile-based resins; polymethyl methacrylate , polymethacrylate resins such as polyethyl methacrylate; polyvinyl ester resins such as polyvinyl acetate; polyvinylidene chloride, polyvinyl chloride, vinyl chloride-vinylidene chloride copolymer, vinylidene chloride-methyl acrylate copolymer Vinyl chloride resin; cellulose resin such as cellulose acetate and cellulose butyrate; polyvinylidene fluoride, polyvinyl fluoride, ethylene-tetrafluoroethylene copolymer, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, tetra Fluoroethylene-hexafluoropropylene copolymer, fluorine-based resin such as tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer; polycarbonate-based resin; polyimide-based resin such as thermoplastic polyimide, polyamideimide, polyetherimide; thermoplastic polyurethane resin; and the like.

The antioxidant is not particularly limited, and may be selected from among amine-based antioxidants, hindered phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, etc., or a combination of two or more thereof. may Among these, an amine-based antioxidant is preferable as a combination with the copper-based stabilizer.

Examples of fillers include fibrous fillers such as glass fiber, powdery fillers such as calcium carbonate, wollastonite, silica, silica alumina, alumina, titanium dioxide, potassium titanate, magnesium hydroxide, and molybdenum disulfide. flake fillers such as hydrotalcite, glass flakes, mica, clay, montmorillonite and kaolin;

The crystal nucleating agent is not particularly limited as long as it is generally used as a crystal nucleating agent for polyamide. Crystal nucleating agents include, for example, talc, calcium stearate, aluminum stearate, barium stearate, zinc stearate, antimony oxide, magnesium oxide, and any mixture thereof. Among these, talc is preferable because it has a large effect of increasing the crystallization rate of polyamide. The crystal nucleating agent may be treated with a silane coupling agent, a titanium coupling agent, or the like for the purpose of improving compatibility with polyamide.

The coloring agent is not particularly limited, and can be appropriately selected from inorganic or organic pigments and dyes depending on the application of the polyamide composition. As the colorant to be blended in the polyamide composition used for the tube for transporting chemical solutions, black inorganic pigments such as carbon black, lamp black, acetylene black, bone black, thermal black, channel black, furnace black, and titanium black are preferred. mentioned.

The antistatic agent is not particularly limited, and may be organic or inorganic. Examples of organic antistatic agents include ionic compounds such as lithium ion salts, quaternary ammonium salts, and ionic liquids; and electronic conductive polymer compounds such as polythiophene, polyaniline, polypyrrole, and polyacetylene. Examples of inorganic antistatic agents include metal oxide conductive agents such as ATO, ITO, PTO, GZO, antimony pentoxide and zinc oxide; and carbon conductive agents such as carbon nanotubes and fullerenes. From the viewpoint of heat resistance, inorganic antistatic agents are preferred. Carbon black, which is a coloring agent, may also function as an antistatic agent.

The plasticizer is not particularly limited as long as it is commonly used as a plasticizer for polyamide. Examples of plasticizers include benzenesulfonic acid alkylamide compounds, toluenesulfonic acid alkylamide compounds, hydroxybenzoic acid alkylester compounds, and hydroxybenzoic acid alkylamide compounds.

The lubricant is not particularly limited as long as it is generally used as a polyamide lubricant. Lubricants include, for example, higher fatty acid compounds, oxyfatty acid compounds, fatty acid amide compounds, alkylenebis fatty acid amide compounds, fatty acid lower alcohol ester compounds, metal soap compounds, and polyolefin waxes. Fatty acid amide compounds, for example, various stearates such as calcium stearate, stearic acid amide, palmitic acid amide, methylene bis stearyl amide, ethylene bis stearyl amide and the like are preferable because of their excellent external lubricating effect. These lubricants may be added internally or externally to the composition. In particular, when a stearate is externally added, there is an effect of reducing the motor load of the extruder.

The content of other additives in the polyamide composition is preferably 50% by mass or less, more preferably 20% by mass or less, and even more preferably 5% by mass or less, relative to 100% by mass of the polyamide composition.

[Method for producing polyamide composition]
The polyamide composition of this embodiment can be produced, for example, by top-feeding the polyamide, the polyolefin, and the copper-based stabilizer to a twin-screw extruder and melt-kneading them.
The method for producing a polyamide composition of the present embodiment includes the step of melt-kneading the mixture containing polyamide, polyolefin, and copper-based stabilizer, so that the end groups of the polyamide and the modified portion of the polyolefin are They react with each other and the resulting composition has excellent flexibility and impact resistance. Moreover, a composition having excellent heat resistance can be obtained by reacting a part of the modified site of the polyolefin (A) and a part of the modified site of the polyolefin (B) with each other. Also, by appropriately adjusting the concentration and blending ratio of the modified sites of the polyolefin, it is possible to obtain a composition having excellent melt-kneadability.

The temperature and time during melt kneading can be appropriately adjusted according to the melting point of the polyamide used, but from the viewpoint of suppressing deterioration of polyolefin, the melt kneading temperature is preferably 380 ° C. or less, and 370 ° C. or less. and more preferably 360° C. or lower. The melt-kneading time is preferably about 1 to 5 minutes.
The method of melt-kneading is not particularly limited, and a method capable of uniformly mixing the polyamide, polyolefin, copper-based stabilizer, and other optional additives can be preferably employed. As the melt-kneader, a single-screw extruder, a twin-screw extruder, a kneader, a Banbury mixer, etc. are preferable, and a twin-screw extruder is more preferable from the viewpoint of good dispersibility of the polyolefin and the copper-based stabilizer and industrial productivity. .

As described above, the polyamide composition of the present embodiment can be obtained by reacting the polyamide, polyolefin (A), and polyolefin (B) with each other during melt kneading. It is preferable to reserve time. Specifically, when using a twin-screw extruder as a melt-kneading device, the polyamide, polyolefin, copper-based stabilizer and other additives added as necessary are added to the first feed port at the base of the twin-screw extruder. It is preferable to feed from the top (top feed).

<Molded body>
Molded articles made of the polyamide composition of the present embodiment can be produced by injection molding, blow molding, extrusion molding, co-extrusion molding, coating molding, compression molding, stretch molding, vacuum molding, using the polyamide composition. It can be obtained by molding by various molding methods such as a molding method, a foam molding method, a rotational molding method, an impregnation method, a laser sintering method, and a hot melt lamination method. Furthermore, the polyamide composition of the present embodiment and other polymers can be composite-molded to obtain molded articles.

The polyamide composition of the present embodiment has excellent extrusion moldability, coextrusion moldability, blow moldability, and coating moldability due to its characteristics, and in order to obtain a molded article, these moldability is utilized. A molding method can be preferably used.

<Application>
Since the molded article of this embodiment contains a polyamide composition as a main component, it exhibits excellent mechanical properties. Furthermore, since the polyamide composition contains a specific polyolefin and a copper-based stabilizer, it is also excellent in heat resistance, flexibility and impact resistance.
Therefore, it can be used for automobile parts, internal combustion engine applications, crude oil drilling and transportation applications, electrical and electronic parts, medical care, food products, household and office supplies, building material related parts, and the like. In particular, due to its excellent heat resistance, flexibility, and impact resistance, it can be used for hollow body applications such as feed tubes, return tubes, evaporative tubes, fuel filler tubes, ORVR tubes, reserve tubes, vent tubes, and other fuel tubes; engine coolant; Cooling water tubes such as tubes, battery coolant tubes, motor coolant tubes, fuel cell cooling tubes; Air suspension tubes and petroleum transportation tubes, road heating tubes, floor heating tubes, infrastructure supply tubes, fire extinguisher and fire extinguishing equipment tubes, medical cooling equipment tubes, ink and paint spraying tubes, and other chemical liquid tubes. . Preferably fuel tubes, engine coolant tubes, battery coolant tubes, motor coolant tubes, fuel cell cooling tubes, urea solution delivery tubes, air conditioner coolant tubes, blow-by tubes, brake booster tubes, brake tubes, oil cooling tubes, turbo It can be used as a duct pipe, air suspension tube, and petroleum transportation tube, and is particularly suitable as a cooling water tube, urea water tube, fuel tube, blow-by tube, oil cooling tube, and brake booster tube. Moreover, as a covering molding, it can be suitably used as an electric wire covering, a bus bar covering, and a wire covering.
The polyamide composition of this embodiment can be used to make a single layer structure and can also be used to make at least one layer of a multi-layer structure. For example, in a tube having a single-layer structure or a multi-layer structure, the polyamide composition of the present embodiment can be suitably used for at least one of the constituent layers.

When the molded product of this embodiment is used as a tube, it can be used after bending, terminal processing, and fastening with various connectors. Generally, the process of bending is implemented by the following flows.
- Preheating process: The tube is preheated and softened so that the tube does not collapse at the required bending dimension.
Bending process: The tube is attached to a jig or deformed by guide rollers to process the tube into a desired shape.
・Heat treatment process: The stress generated in the tube is relaxed and the shape is fixed. The heat treatment temperature must be between the glass transition temperature and the melting point of the material forming the tube, and the higher the temperature, the shorter the heat treatment time required to fix the shape. The heat treatment temperature Tf is preferably in the range of Tm-80°C ≤ Tf ≤ Tm-10°C, and Tm-60°C ≤ Tm, where Tm is the melting point of the material with the lowest melting point among the materials constituting the tube. More preferably, Tf≤Tm-15°C. By setting the temperature within the above range, it is possible to carry out the bending process in an economical time and prevent the tube material from melting due to the heat treatment.

Various methods such as press fitting, spin welding, and laser welding can be used to fasten the connector. When the usage environment is high temperature and high pressure, it is desirable to use a welding method such as a spin welding method or a laser welding method from the viewpoint of reliability. When using the welding method, it is desirable that the tube material and the connector material have high chemical affinity. With the tube placed inside the connector, it is desirable to irradiate the laser from the top of the connector in the circumferential direction of the tube.

The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these.

Physical properties in Examples, Comparative Examples, and Production Examples were measured according to the following methods.
[Measurement of physical properties of polyamide]
・Intrinsic viscosity For the semi-aromatic polyamide (sample) obtained in the production example, the intrinsic viscosity (dl/g) at a concentration of 0.2 g/dl and a temperature of 30°C using concentrated sulfuric acid as a solvent was obtained from the following relational expression. .
η _inh =[ln(t ₁ /t ₀ )]/c
In the above relational expression, η _inh represents the intrinsic viscosity (dl / g), t ₀ represents the flow time (seconds) of the solvent (concentrated sulfuric acid), t ₁ represents the flow time (seconds) of the sample solution, and c represents the concentration (g/dl) of the sample in the sample solution (ie 0.2 g/dl).

- Melting point The melting point of the semi-aromatic polyamide (sample) obtained in Production Examples was measured using a differential scanning calorimeter "DSC7020" manufactured by Hitachi High-Tech Science Corporation.
The melting point was measured according to ISO11357-3 (2nd edition, 2011). Specifically, in a nitrogen atmosphere, the sample was heated from 30 ° C. to 340 ° C. at a rate of 10 ° C./min, held at 340 ° C. for 5 minutes to completely melt the sample, and then heated at 10 ° C./min. Cooled to 50°C at speed and held at 50°C for 5 minutes. The peak temperature of the melting peak that appears when the temperature is again raised to 340°C at a rate of 10°C/min is the melting point (°C), and if there are multiple melting peaks, the peak temperature of the highest melting peak is the melting point (°C). bottom.

Content of Terminal Amino Groups 1 g of the semi-aromatic polyamide obtained in Production Example was dissolved in 35 mL of phenol, and 2 mL of methanol was mixed therein to prepare a sample solution. Using thymol blue as an indicator, titration was performed using a 0.01N hydrochloric acid aqueous solution to measure the terminal amino group content ([NH ₂ ], unit: μeq/g) of the semi-aromatic polyamide.

-Terminal carboxyl group content 0.5 g of the semi-aromatic polyamide obtained in Production Example was dissolved in 40 mL of ortho-cresol to prepare a sample solution. The obtained sample solution is titrated using a 0.01N ethanolic potassium hydroxide solution using a potentiometric titrator manufactured by Kyoto Electronics Industry Co., Ltd., and the potential inflection point is detected. , the terminal carboxyl group content ([COOH], unit: μeq/g) of the semi-aromatic polyamide was measured.

- Polydispersity index The number average molecular weight Mn and weight average molecular weight Mw of the semi-aromatic polyamide obtained in the production example were measured by gel permeation chromatography, and the polydispersity index was determined by the following formula.
Polydispersity index = Mw/Mn
The above number-average molecular weight and weight-average molecular weight are measured using HLC-8320GPC manufactured by Tosoh Corporation and column TSK-gel SuperHM-N manufactured by Tosoh Corporation, using 10 mM trifluoroacetic acid hexafluoro-2-propanol as an eluent. It was measured at a temperature of 40° C. and calculated in terms of polymethyl methacrylate.

[Evaluation items of polyamide composition]
• Functional Group Concentration As the functional group concentration in the polyamide compositions obtained in Examples and Comparative Examples, Z was calculated from the following formula (1) based on the amount of each component used.
formula (1)
Z=1000×(|[ANH]−[EPO]|+[EPO])/X ²
In the above formula (1), [EPO], [ANH] and X are as follows.
[EPO]: Concentration of unsaturated epoxide derived from polyolefin per unit mass of polyamide composition (mmol/kg).
[ANH]: Concentration of unsaturated dicarboxylic acid anhydride derived from polyolefin per unit mass of polyamide composition (mmol/kg).
X: Polyolefin content (% by mass) in the polyamide composition.
The unsaturated epoxide concentration [EPO] and the unsaturated dicarboxylic acid concentration [ANH] in the above formula (1) were calculated according to the following formula (2).
formula (2)
[EPO] or [ANH] = 100 x N x W/M
In the above formula (2), M, W and N are as follows.
M: Molecular weight of unsaturated epoxide or unsaturated dicarboxylic acid anhydride.
W: % by mass of unsaturated epoxide or unsaturated dicarboxylic acid anhydride contained in polyolefin (A) or polyolefin (B). In this example, W is a catalog value.
N: Mass % of polyolefin (A) or polyolefin (B) per unit mass of polyamide composition.
In Examples and Comparative Examples, calculations were made with the molecular weight of glycidyl methacrylate as 142.2 (g/mol) and the molecular weight of maleic anhydride as 98.06 (g/mol).

- Stability during melt-kneading In Examples and Comparative Examples, processing stability during production of polyamide compositions with a twin-screw extruder was evaluated according to the following four levels. The order of A, B, B' and C is judged to be superior in stability.
A: Stable production is possible without vent-up or strand breakage at the vacuum vent port.
B: The strand is stable, but polyolefin that bleeds out tends to accumulate at the vacuum vent port, and there is concern about foreign matter.
The bleed-out of polyolefin is considered to be caused by the low affinity between polyamide and polyolefin.
B': The strand is stable, but the viscosity of the composition is high and the pressure of the twin-screw extruder is very high. In addition, a large amount of deposits were present near the die after compounding. Epoxide is considered to be a phenomenon that occurs due to its high reactivity with polyamide.
C: Strand breaks occur frequently, and it is difficult to obtain pellets.
In addition, in the composition in which strand breakage of C occurs frequently, the domain size of the polyolefin in the matrix of the polyamide is enlarged, and the affinity of the polyolefin for the polyamide is low. Melt viscosity, tensile test, and impact resistance test were not performed on the polyamide composition of "C" because pellets could not be obtained.

・Melt viscosity The melt viscosity of the polyamide compositions obtained in Examples and Comparative Examples was measured using a capillograph (manufactured by Toyo Seiki Seisakusho Co., Ltd.) at a barrel temperature of 300 ° C. and a shear rate of 121.6 sec ^-1 (capillary: inner diameter 1 The melt viscosity (Pa·s) was measured under the conditions of (0 mm×10 mm length, extrusion speed 10 mm/min) and used as an index of fluidity.

<<Preparation of test piece>>
Using an injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. (clamping force: 100 tons, screw diameter: φ32 mm), using the polyamide compositions obtained in Examples and Comparative Examples, the melting point of the polyamide was 20 The polyamide composition is molded using a T-runner mold under the conditions of a cylinder temperature of ~ 30 ° C. and a mold temperature of 140 ° C., and a multi-purpose test piece type A1 (a dumbbell-shaped test piece described in JIS K7139; 4 mm thick, total length 170 mm, parallel portion length 80 mm, parallel portion width 10 mm). Then, a rectangular parallelepiped test piece (dimensions: length x width x thickness = 80 mm x 10 mm x 4 mm) was cut out from the multi-purpose test piece and used as a test piece for evaluation of tensile test and impact resistance test.

· Tensile test Using the multi-purpose test piece type A1 (4 mm thickness) prepared by the above method, in accordance with ISO527-1 (2012 2nd edition), using Autograph (manufactured by Instron), 23 ° C. Tensile strength (maximum point) (MPa), tensile elongation at break (%) and tensile elastic modulus (GPa) were measured. The tensile modulus was measured at a tensile speed of 1 mm/min in the strain range of 0.05 to 0.25%, and 50 mm/min after 0.3% strain.

· Impact resistance test A test piece (4 mm thick, total length 80 mm, width 10 mm, notched) is prepared by cutting from the multi-purpose test piece type A1 (4 mm thickness) prepared by the above method, ISO179-1 (2010 second Version), using an impact tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.), notched Charpy impact values at 23° C. and −40° C. were measured to evaluate impact resistance (kJ/m ² ).

· Retention rate of impact resistance strength The test piece for impact resistance test prepared by the above method was placed in a constant temperature bath ("DE-303" manufactured by Mita Sangyo Co., Ltd.) set at 160 ° C. for 1000 hours. After 1000 hours, the test piece was removed from the constant temperature bath and subjected to an impact resistance test at 23° C. in the same manner as described above, and the impact resistance strength of the heated test piece was measured.
Long-term heat resistance was evaluated by obtaining impact strength retention from the following formula (X).
Impact strength retention (%) = {Impact strength after 1000 hours/Initial impact strength} x 100 Formula (X)

《Preparation of tube》
A tube molding device in which a straight die (die inner diameter: φ21.0 mm, mandrel outer diameter: φ14.9 mm) is connected to a single-screw extruder (screw diameter: φ50 mm, L/D = 28) manufactured by IKK Co., Ltd. was used to discharge the polyamide compositions obtained in Examples and Comparative Examples under conditions of a cylinder temperature of 280°C, a die temperature of 280°C, and a screw rotation speed of 30 rpm. Subsequently, dimensional control and cooling were carried out in a vacuum sizing tank, and a tube having an outer diameter of 8.0 mm and an inner diameter of 6.0 mm was produced at a take-up speed of 10 m/min.

・ Whitening resistance test The end of the tube obtained by the above method was flared with a conical heater heated to 80 ° C. After confirming that the temperature had decreased to room temperature, the outermost diameter of the fir tree part A quick connector with a diameter of 8.9 mm was press-fitted, and the presence or absence of whitening occurring on the surface of the end of the tube was visually confirmed. Whitening resistance was evaluated as A when no whitening was observed and C when whitening was observed. Note that the flare processing was performed to facilitate center alignment when press-fitting the connector.

[Manufacturing example]
Production Example 1 [Production of Polyamide PA-1]
9870.6 g (59.42 mol) of terephthalic acid, a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [50/50 (molar ratio)] 9497.4 g (60.30 mol), benzoin 142.9 g (1.17 mol) of acid, 9.8 g of sodium hypophosphite monohydrate (0.05% by mass based on the total mass of raw materials) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters. and replaced with nitrogen. While stirring, the temperature inside the autoclave was raised to 220° C. over 2 hours. At this time, the pressure inside the autoclave increased to 2 MPa. After continuing the reaction for 2 hours, the temperature was raised to 230° C., and then the temperature was kept at 230° C. for 2 hours, and the reaction was carried out while the pressure was maintained at 2 MPa by gradually removing water vapor. Next, the pressure was lowered to 1 MPa over 30 minutes, and the reaction was continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.2 dl/g. This was pulverized to a particle size of 2 mm or less using a Hosokawa Micron flake crusher, dried at 100° C. under reduced pressure for 12 hours, and then solid-phase polymerized at 230° C. and 13 Pa (0.1 mmHg) for 10 hours to obtain a white powder. A polyamide resin (polyamide PA-1) was obtained.
Polyamide PA-1 contains terephthalic acid units, 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units (1,9-nonanediamine units/2-methyl-1,8-octanediamine units=50/ 50 (molar ratio)), the melting point is 265° C., the intrinsic viscosity [η _inh ] is 1.26 dl/g, the terminal amino group content ([NH ₂ ]) is 15.6 μeq/g, the terminal carboxyl group content ( [COOH]) was 55.1 μeq/g. Moreover, the polydispersity index determined by gel permeation chromatography was 5.0.

Production Example 2 [Production of Polyamide PA-2]
9870.6 g (59.42 mol) of terephthalic acid, a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [50/50 (molar ratio)] 9497.4 g (60.90 mol), benzoin 142.9 g (1.17 mol) of acid, 9.8 g of sodium hypophosphite monohydrate (0.05% by mass based on the total mass of raw materials) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters. and replaced with nitrogen. Thereafter, polymerization was carried out in the same manner as in Production Example 1 to obtain a white polyamide resin (polyamide PA-2).
Polyamide PA-2 has a melting point of 265° C., an intrinsic viscosity [η _inh ] of 1.28 dl/g, a terminal amino group content ([NH ₂ ]) of 51.5 μeq/g, and a terminal carboxyl group content ([COOH]). was 23.4 μeq/g. Moreover, the polydispersity index determined by gel permeation chromatography was 4.1.

[Examples and Comparative Examples]
Examples 1 to 7 and Comparative Examples 1 to 13 were prepared according to the formulations shown in Table 1 or Table 2 to obtain polyamide compositions.
Specifically, the polyamide, copper-based stabilizer, antioxidant, lubricant, and colorant shown in Table 1 or Table 2 are premixed at a predetermined mass ratio, and together with polyolefin (A) and polyolefin (B) (however, , together with polyolefin (A) in Comparative Example 10, and together with polyolefin (C) in Comparative Examples 11 to 13), into the upstream feed port of a twin-screw extruder ("TEM-26SS" manufactured by Toshiba Machine Co., Ltd.). Cylinder temperature 300-320°C (melt-kneading temperature 310-340°C, melt-kneading temperature indicates resin temperature), rotation speed 150 rpm, discharge 10 kg/hr. , cooled and cut to produce a polyamide composition in the form of pellets.
Using the pellets described above, test pieces for evaluating various physical properties were produced, and various evaluations were performed by the methods described above. The results are shown in Tables 1 and 2. At this time, the presence or absence of vent-up at the vacuum vent port in the downstream portion was confirmed.
In addition, in Table 1, *1 indicates that measurement is not possible.

Each component shown in Tables 1 and 2 is as follows.
<Polyamide>
Polyamide PA-1 obtained in Production Example 1
Polyamide PA-2 obtained in Production Example 2

<Polyolefin (A)>
Lotader® AX8930: Copolymer of ethylene, methyl acrylate and glycidyl methacrylate [Et/MA/GMA=72/25/3 (mass ratio)]
Lotader® AX8900: Copolymer of ethylene, methyl acrylate and glycidyl methacrylate [Et/MA/GMA = 68/24/8 (mass ratio)]
<Polyolefin (B)>
Lotader® 4700: Copolymer of ethylene, ethyl acrylate and maleic anhydride [Et/EA/MAH=68.7/30/1.3 (mass ratio)]
Lotader® 3410: Copolymer of ethylene, butyl acrylate and maleic anhydride [Et/BA/MAH=80/17/3.1 (mass ratio)]
<Polyolefin (C)>
Tafmer (registered trademark) MH7010: Elastomer obtained by modifying ethylene-butene copolymer with maleic anhydride [acid anhydride group concentration: 50 μeq/g], manufactured by Mitsui Chemicals, Inc. (for comparative example)

<Copper-based stabilizer>
KG HS01-P: Molar ratio: CuI/KI = 10/1, manufactured by PolyAd Services <Antioxidant>
Naugard® 445: 4,4′-bis(α,α-dimethylbenzyl)diphenylamine from Addivant

<Lubricant>
WH-255: amide wax light amide, manufactured by Kyoeisha Chemical Co., Ltd. <colorant>
#980B: carbon black, manufactured by Mitsubishi Chemical Corporation

From Table 1, it can be seen that the polyamide compositions of Examples 1 to 7 have both high heat resistance, production stability in melt-kneading, high tensile elongation at break, low-temperature impact resistance, and whitening resistance.
Since the composition of Comparative Example 1 did not contain polyolefin (A), it had insufficient affinity with polyamide, and a composition compatibilized by a compound could not be obtained.
Since the compositions of Comparative Examples 2, 3 and 5 did not contain a copper-based stabilizer, the impact strength retention rate was low and the heat aging resistance was insufficient.
The compositions of Comparative Examples 4, 6, and 8 had insufficient stability during melt-kneading because the value of Z was smaller than the range defined in this embodiment. Furthermore, in Comparative Example 6, a compatibilized composition could not be obtained.
The composition of Comparative Example 7 had an insufficient tensile elongation at break because [B]/[A] did not fall within the range specified in this embodiment.
The composition of Comparative Example 9 had a Z value larger than the range defined in this embodiment, and therefore had poor tensile elongation at break and tensile elastic modulus, insufficient flexibility, and poor impact strength retention. and the heat aging resistance was not sufficient.
Since the composition of Comparative Example 10 did not contain the polyolefin (B), the melt viscosity was very high and the balance between flexibility and viscosity was poor.
Since the compositions of Comparative Examples 11 to 13 did not contain polyolefin (A) and polyolefin (B), whitening resistance was insufficient even if polyolefin (C) was contained instead of these.

Claims

A composition comprising a polyamide, a polyolefin and a copper-based stabilizer,
The polyolefin contains at least one polyolefin (A) containing a copolymer of ethylene, an alkyl (meth)acrylate and an unsaturated epoxide, and at least one polyolefin (B) containing an unsaturated dicarboxylic acid anhydride, and The mass ratio [B]/[A] of the content [B] of the polyolefin (B) to the content [A] of the polyolefin (A) is 0.1 to 2.9,
A polyamide composition having a value Z of 33 to 200 calculated from the following formula (1).
Z = 1000 × (|[ANH]−[EPO]|+[EPO])/X 2 formula (1)
The [EPO] is the concentration (mmol/kg) of unsaturated epoxide derived from the polyolefin per unit mass of the composition.
The [ANH] is the concentration (mmol/kg) of the unsaturated dicarboxylic anhydride derived from the polyolefin per unit mass of the composition.
The above X is the polyolefin content (% by mass) in the composition.
The polyamide composition according to claim 1, wherein the polyamide contains 50 mol% or more of at least one selected from terephthalic acid units and naphthalenedicarboxylic acid units based on all dicarboxylic acid units.
The polyamide composition according to claim 1 or 2, wherein the polyamide contains 60 mol% or more of aliphatic diamine units having 4 to 13 carbon atoms or meta-xylylenediamine units relative to all diamine units.
The aliphatic diamine units are 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,10-decane. 4. The polyamide composition according to claim 3, which is a unit derived from at least one aliphatic diamine selected from the group consisting of diamines.
The polyamide composition according to claim 3 or 4, wherein the aliphatic diamine unit is a unit derived from at least one aliphatic diamine selected from 1,9-nonanediamine and 2-methyl-1,8-octanediamine. thing.
The polydispersity index of the polyamide measured by gel permeation chromatography is 3.7 or more, the content of terminal amino groups in the polyamide is 10 to 70 μeq / g, and the content of terminal carboxyl groups is 10 to 70 μeq / The polyamide composition according to any one of claims 1 to 5, which is g.
The polyamide composition according to any one of claims 1 to 6, wherein the polyolefin content is 14 to 40% by mass.
The polyamide composition according to any one of claims 1 to 7, wherein the polyolefin content is 15 to 30% by mass.
The polyamide composition according to any one of claims 1 to 8, wherein the polyolefin (B) is a copolymer of ethylene, an alkyl (meth)acrylate and an unsaturated dicarboxylic acid anhydride.
The polyamide composition according to any one of claims 1 to 9, wherein the content of the copper-based stabilizer is 0.01 to 2% by mass.
The copper-based stabilizer comprises at least one copper compound selected from the group consisting of copper iodide, copper bromide, and copper acetate, and at least one metal selected from the group consisting of potassium iodide and potassium bromide. A polyamide composition according to any one of claims 1 to 10, comprising a halide.
At least one selected from the group consisting of polymers other than the polyamide and the polyolefin, antioxidants, fillers, crystal nucleating agents, colorants, antistatic agents, plasticizers, lubricants, flame retardants, and flame retardant aids The polyamide composition according to any one of claims 1 to 11, comprising an additive of
A method for producing a polyamide composition according to any one of claims 1 to 12,
A method for producing a polyamide composition, wherein the polyamide, the polyolefin, and the copper-based stabilizer are top-fed to a twin-screw extruder and melt-kneaded.
Use of the polyamide composition according to any one of claims 1 to 12 for making a single-layer structure or for making at least one layer of a multilayer structure.
A molded article made of the polyamide composition according to any one of claims 1 to 12.
The molded product according to claim 15, which is an extruded product, a co-extruded product or a blow molded product.
Fuel tubes, engine coolant tubes, battery coolant tubes, motor coolant tubes, fuel cell cooling tubes, urea solution delivery tubes, air conditioner coolant tubes, blow-by tubes, brake booster tubes, brake tubes, oil cooling tubes, turbo duct pipes , an air suspension tube or an oil transportation tube.