JP6876715B2 - Polyamide-based thermoplastic elastomer compositions, moldings and hollow moldings - Google Patents

Description

The present invention relates to a polyamide-based thermoplastic elastomer composition, a molded product, and a hollow molded product.

Unlike vulcanized rubber, thermoplastic elastomers do not require a vulcanization process and can be processed with a normal thermoplastic resin molding machine, so their application to various applications such as automobile parts and machine parts is being considered. Has been done. In particular, polyester-based thermoplastic elastomers are excellent in durability, oil resistance, and heat resistance, and because of their high elastic modulus, the members can be made thinner, which meets the needs for weight reduction and cost reduction. It is being considered as a material.

For example, chloroprene rubber material has been mainly used as a material for resin flexible boots having a bellows shape, but in recent years, the manufacturing process can be simplified, heat resistance is excellent, and boots are further used. Due to the advantage of having a long durable life as a material, substitution with polyester-based thermoplastic elastomers is being promoted (for example, Patent Document 1).

Further, since polyamides typified by polyamide 6 and polyamide 6/6 are excellent in physical properties such as molding processability, mechanical properties, and chemical resistance, they are used for automobiles, industrial materials, clothing, electric / electronic, etc. It is widely used as a component material in various fields such as industrial use.

For example, as an industrial tube, a metal tube has been the mainstream in the past, but in recent years, resinification is progressing in order to reduce the weight. For example, polyamide 11 and polyamide 12 are being widely used in tubes and hose molded products such as fuel pipes for automobiles because of their excellent flexibility. Further, as a method for further enhancing the flexibility of the polyamide 12 and the impact resistance at a low temperature, Patent Document 2 proposes a composition composed of the polyamide 12, a plasticizer, and a modified polyolefin.

Japanese Unexamined Patent Publication No. 2001-173672 Japanese Unexamined Patent Publication No. 2000-248174

However, the polyester-based thermoplastic elastomer as shown in Patent Document 1 has a problem that the molded product cannot maintain its strength and shape at a high temperature because it becomes flexible at a high temperature and its elastic modulus decreases.

Further, although the molded product of the resin composition containing the aliphatic polyamide as shown in Patent Document 2, the plasticizer and the modified polyolefin has flexibility at room temperature, the elastic modulus is high at high temperature. There was a problem that it was easy to decrease. Therefore, not only the strength and shape cannot be maintained under high temperature, but also the fluid heated to high temperature (for example, coolant liquid [hereinafter, may be abbreviated as LLC]] or automatic transmission fluid [hereinafter, may be abbreviated as ATF]. , When used in brake fluid [hereinafter, may be abbreviated as BF], etc.), there is a problem that the oil resistance is not sufficient and the strength tends to be significantly reduced due to deterioration over time.

The present invention has been made in view of the above circumstances, and is a polyamide-based thermoplastic capable of imparting a molded product having flexibility at room temperature, maintaining elastic modulus even at high temperature, and having high oil resistance. It is an object of the present invention to provide an elastomer composition.

[1] All the dicarboxylic acid structural units containing 80 mol% or more of the aliphatic dicarboxylic acid structural units having 2 to 14 carbon atoms and the aliphatic diamine structural units having 4 to 12 carbon atoms are included. An aliphatic polyamide composed of a diamine structural unit containing 80 mol% or more of a diamine structural unit, or an aliphatic polyamide composed of an amidocarboxylic acid structural unit or a lactam structural unit, which is measured by differential scanning calorie measurement (DSC). Polymerized by an aliphatic polyamide [I] having a melting point (Tm) of 200 to 290 ° C., an ethylene structural unit [a], an α-olefin structural unit [b] having 3 to 20 carbon atoms, and a metallocene-based catalyst. Ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] containing a non-conjugated polyene structural unit [c] having one or more possible carbon-carbon double bonds in one molecule, and a functional group structural unit The mass ratio [V] to the aliphatic polyamide [I] as an olefin polymer [III] containing 0.3 to 5.0% by mass of, a phenol resin-based cross-linking agent [IV], and a cross-linking aid [V]. ] / [I] is a crosslinked product of a rubber composition containing a zinc compound having a value of 0.0001 to 0.02, which is a polyamide-based thermoplastic elastomer composition.
[2] The aliphatic polyamide [I] is one or more selected from the group consisting of polyamide 6, polyamide 6/6, polyamide 6/10, polyamide 6/12, polyamide 9/2 and polyamide 10/10. The polyamide-based thermoplastic elastomer composition according to [1].
[3] The polyamide-based thermoplastic elastomer composition according to [2], wherein the aliphatic polyamide [I] is at least one selected from the group consisting of polyamide 6, polyamide 6/6 and polyamide 6/10.
[4] The melt flow rate (MFR) of the aliphatic polyamide [I] at 290 ° C. and 2.16 kg load according to ISO 1133 is 0.1 to 100 g / 10 minutes, whichever of [1] to [3]. The polyamide-based thermoplastic elastomer composition described in the above.
[5] The functional group structural unit of the olefin polymer [III] contains a structural unit derived from one or more functional groups selected from the group consisting of a carboxylic acid group, an ester group, an ether group, an aldehyde group and a ketone group. , [1] to [4]. The polyamide-based thermoplastic elastomer composition according to any one of [1] to [4].
[6] The polyamide-based thermoplastic elastomer composition according to [5], wherein the functional group structural unit of the olefin-based polymer [III] is a maleic anhydride structural unit.
[7] The polyamide-based thermoplastic elastomer composition according to any one of [1] to [6], wherein the phenol-resin-based cross-linking agent [IV] contains a halogenated phenol-resin-based cross-linking agent.
[8] The polyamide-based thermoplastic elastomer according to any one of [1] to [7], wherein the zinc compound is one or more selected from the group consisting of zinc oxide, zinc carbonate, zinc carboxylate and zinc hydroxide. Composition.
[9] The polyamide-based thermoplastic elastomer composition according to [8], wherein the zinc compound is zinc oxide.
[10] The aliphatic polyamide [I] is 10 to 60% by mass with respect to a total of 100% by mass of [I], [II], [III] and [IV], and the ethylene / α-olefin / non-ethylene / α-olefin / non. The conjugated polyene copolymer rubber [II] is 33 to 86% by mass, the olefin polymer [III] is 0.1 to 30% by mass, and the phenol resin cross-linking agent [IV] is 1 to 10% by mass. The polyamide-based thermoplastic elastomer composition according to any one of [1] to [9], which comprises.
[11] The matrix phase containing the aliphatic polyamide [I], the ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] dispersed and crosslinked in the matrix phase, and the olefin polymer [II]. III] The polyamide-based thermoplastic elastomer composition according to [1] to [10], which has a dispersed phase containing and.
[12] The polyamide-based thermoplastic elastomer composition according to [11], wherein the average particle size of the dispersed phase analyzed by a transmission electron microscope image is 0.3 to 5.0 μm.
[13] [11] or [12], the total area of the dispersed phase having a particle size of 3.0 μm or more analyzed by a transmission electron microscope image is 10% or less with respect to the total area of the analysis region. The polyamide-based thermoplastic elastomer composition according to.
[14] A molded product obtained from the polyamide-based thermoplastic elastomer composition according to any one of [1] to [13].
[15] A hollow molded product obtained from the polyamide-based thermoplastic elastomer composition according to any one of [1] to [13].
[16] The hollow molded body according to [15], wherein the hollow molded body is an automobile-related part.
[17] The hollow molded body according to [16], wherein the automobile-related parts are intake / exhaust system parts.
[18] The hollow molded body according to [17], wherein the intake / exhaust system parts are an air hose, an air duct, a turbo duct, a turbo hose, an intake manifold, or an exhaust manifold.

According to the present invention, it is possible to provide a polyamide-based thermoplastic elastomer composition which has flexibility at room temperature, maintains elastic modulus even at high temperature, and can impart a molded product having high oil resistance. ..

1A and 1B are TEM photographs of the cut surface of the polyamide-based thermoplastic elastomer composition according to the embodiment of the present invention.

The present inventors have made an aliphatic polyamide [I], a copolymer rubber [II], an olefin polymer [III] containing 0.3 to 5.0% by mass of a functional group structural unit, and a phenol resin type. The polyamide-based thermoplastic elastomer composition obtained by cross-linking (dynamically cross-linking) a rubber composition containing a cross-linking agent [IV] and a predetermined amount of a zinc compound as a cross-linking aid [V] is flexible at room temperature. It has been found that a molded product having high oil resistance can be imparted while maintaining the elastic coefficient even at a high temperature (reducing the decrease in the elastic coefficient at a high temperature).

The reason for this is not clear, but it is speculated as follows. The polyamide-based thermoplastic elastomer composition obtained by dynamically cross-linking the above rubber composition is a matrix phase (sea phase) containing an aliphatic polyamide [I] as a main component and a cross-linked copolymer rubber [II]. It has a dispersed phase (island phase) containing olefin polymer [III] as a main component, and the average diameter of the dispersed phase is relatively small and is finely dispersed. Since the polyamide-based thermoplastic elastomer composition having such a microstructure has increased mechanical strength, it is easy to maintain the elastic modulus even at a high temperature. Further, since the copolymer rubber [II] constituting the dispersed phase is crosslinked, swelling due to oil is unlikely to occur, and oil resistance is likely to be improved.

Furthermore, by using an aliphatic polyamide [I] (preferably a total aliphatic polyamide) as the polyamide, the crystallinity of the matrix phase can be increased as compared with the use of, for example, a semi-aromatic polyamide. As a result, not only the elastic modulus of the matrix phase at high temperature is more easily maintained, but also the dispersed phase is easily fixed, so that the swelling of the copolymer rubber [II] constituting the dispersed phase due to oil is further reduced. sell. As a result, it is considered that the elastic modulus can be more easily maintained even at a high temperature and the oil resistance is further enhanced. Such a molded product may also have an effect of being excellent in resistance to hydrolysis (acid resistance, hydrolysis resistance) in an acidic medium at a high temperature.

The molded product obtained from such a polyamide-based thermoplastic elastomer composition is suitable as a hollow molded product for, for example, automobile-related parts. The present invention has been made based on such findings.

1. 1. Polyamide-based thermoplastic elastomer composition The polyamide-based thermoplastic elastomer composition of the present invention comprises an aliphatic polyamide [I], an ethylene / α-olefin / non-conjugated polyene copolymer rubber [II], and an olefin polymer [II]. It is a crosslinked product (dynamic crosslinked product) of a rubber composition containing [III], a phenol resin-based crosslinking agent [IV], and a zinc compound as a crosslinking aid [V]. The crosslinked product is a partially crosslinked product or a completely crosslinked product.

1-1. Aliphatic Polyamide [I]
The aliphatic polyamide [I] contains "a structural unit containing an amide bond [-NH-C (= O)-] and does not contain an aromatic ring" (an amide bond-containing structural unit containing no aromatic ring) as a main component. Including. Here, "containing as a main component" means that the content ratio of the amide bond-containing structural unit containing no aromatic ring is 80 mol with respect to the total number of moles of the amide bond-containing structural unit constituting the aliphatic polyamide [I]. % Or more, preferably 90 to 100 mol%.

The aliphatic polyamide [I] may be obtained by polycondensation reaction of a dicarboxylic acid and a diamine, may be obtained by polycondensation reaction of an aminocarboxylic acid, or ring-opening polymerization of lactam. It may be obtained by reacting. That is, the aliphatic polyamide [I] is composed of at least one of an amide bond-containing structural unit composed of a dicarboxylic acid structural unit and a diamine structural unit; an aminocarboxylic acid structural unit; and a lactam structural unit.

(Dicarboxylic acid structural unit / diamine structural unit)
The dicarboxylic acid structural unit constituting the aliphatic polyamide [I] includes an aliphatic dicarboxylic acid structural unit. The aliphatic dicarboxylic acid is preferably an aliphatic dicarboxylic acid having 2 to 14 carbon atoms, more preferably 4 to 14 carbon atoms, and further preferably 6 to 12 carbon atoms. Examples of aliphatic dicarboxylic acids include oxalic acid (C2), adipic acid (C6), pimelic acid (C7), suberic acid (C8), azelaic acid (C9), sebacic acid (C10), dodecanedioic acid (C12). And tetradecanedioic acid (C14) and the like. Of these, adipic acid (C6) and dodecanedioic acid (C12) are preferable. The aliphatic dicarboxylic acid may be one kind or a combination of two or more kinds.

The content ratio of the aliphatic dicarboxylic acid structural unit is preferably 80 mol% or more with respect to the total number of moles of the dicarboxylic acid structural unit constituting the aliphatic polyamide [I]. When the content ratio of the aliphatic dicarboxylic acid structural unit is 80 mol% or more, the crystallinity of the aliphatic polyamide [I] is likely to increase, and sufficient heat resistance and oil resistance can be imparted to the molded product. The content ratio of the aliphatic dicarboxylic acid structural unit is more preferably 85 to 100 mol% and further preferably 90 to 100 mol% with respect to the total number of moles of the dicarboxylic acid structural unit.

The dicarboxylic acid structural unit constituting the aliphatic polyamide [I] may further contain a small amount of alicyclic dicarboxylic acid structural unit or aromatic dicarboxylic acid structural unit as long as the effect of the present invention is not impaired.

The diamine structural unit constituting the aliphatic polyamide [I] includes an aliphatic diamine structural unit. The aliphatic diamine is preferably an α, ω-linear aliphatic diamine having 4 to 12 carbon atoms, more preferably 6 to 10 carbon atoms. Examples of aliphatic diamines include tetramethylenediamine, hexamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine and the like. Among them, tetramethylenediamine, hexamethylenediamine, nonamethylenediamine and decamethylenediamine are preferable, and tetramethylenediamine and hexamethylenediamine are more preferable. The aliphatic diamine may be one kind or a combination of two or more kinds.

The content ratio of the aliphatic diamine structural unit is preferably 80 mol% or more with respect to the total number of moles of the diamine structural unit constituting the aliphatic polyamide [I]. When the content ratio of the aliphatic diamine structural unit is 80 mol% or more, the crystallinity of the aliphatic polyamide [I] is likely to increase, and sufficient heat resistance and oil resistance can be imparted to the molded product. The content ratio of the aliphatic diamine structural unit is more preferably 85 to 100 mol% and further preferably 90 to 100 mol% with respect to the total number of moles of the diamine structural unit.

The diamine structural unit constituting the aliphatic polyamide [I] may further contain a small amount of alicyclic diamine structural unit or aromatic diamine as long as the effect of the present invention is not impaired.

(Aminocarboxylic acid structural unit)
The aminocarboxylic acid that can constitute the aliphatic polyamide [I] can be an aminocarboxylic acid having 6 to 12 carbon atoms, preferably 6 to 10 carbon atoms. Examples of such aminocarboxylic acids include 6-aminocaproic acid, 7-aminoheptanic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and the like. Only one type of aminocarboxylic acid may be used, or two or more types may be combined.

(Lactam structural unit)
The lactam that can constitute the aliphatic polyamide [I] can be a lactam having 6 to 12 carbon atoms, preferably 6 to 10 carbon atoms. Examples of such lactams include α-pyrrolidone, ε-caprolactam, undecane lactam, ω-laurolactam, ε-enantractam and the like. Only one type of lactam may be used, or two or more types may be combined.

Examples of the aliphatic polyamide [I] include polyamide 6, polyamide 6/6, polyamide 4/6, polyamide 6/10, polyamide 6/12, polyamide 6/14, polyamide 6/13, polyamide 6/15, and polyamide. 6/16, Polyamide 9/2, Polyamide 9/10, Polyamide 9/12, Polyamide 9/13, Polyamide 9/14, Polyamide 9/15, Polyamide 6/16, Polyamide 9/36, Polyamide 10/10, Polyamide Includes 10/12, Polyamide 10/13, Polyamide 10/14, Polyamide 12/10, Polyamide 12/12, Polyamide 12/13, Polyamide 12/14.
Among them, polyamide 6, polyamide 6/6, polyamide 6/10, polyamide 6/12, polyamide 9/2 and polyamide 10/10 are preferable, and polyamide 6, polyamide 6/6 and polyamide are preferable because they have good heat resistance. 6/10 is more preferable. The aliphatic polyamide [I] may be used alone or in combination of two or more.

From the viewpoint of thermal stability during compounding and molding, the aliphatic polyamide [I] preferably has at least a part of the terminal groups of the molecular chains sealed with an end-capping agent. In particular, from the viewpoint of melt stability, heat resistance, and hydrolysis resistance, the amount of terminal amino groups in the molecular chain is preferably 0.1 to 300 mmol / kg, more preferably 5 to 300 mmol / kg, and even more preferably 5 to. It is 200 mmol / kg, particularly preferably 5 to 100 mmol / kg.

The terminal encapsulant is not particularly limited as long as it is a monofunctional compound having reactivity with an amino group or a carboxyl group at the molecular terminal of polyamide, but from the viewpoint of reactivity and stability of the encapsulating end, etc. Monocarboxylic acid or monoamine is preferable, and monocarboxylic acid is more preferable from the viewpoint of ease of handling and the like. In addition, acid anhydride monoisocyanate, monoacid halide, monoesters, monoalcohols and the like can also be used.

The monocarboxylic acid used as the terminal encapsulant is not particularly limited as long as it has reactivity with an amino group. Examples of monocarboxylic acids are aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, capric acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid and isobutyl acid. Acids; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; aromatic monocarboxylic acids such as benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid and phenylacetic acid. These can be used in combination of two or more. Among them, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, benzoic acid, etc. Acids are more preferred.

The monoamine used as the terminal encapsulant is not particularly limited as long as it has reactivity with a carboxyl group. Examples of monoamines include aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine and dibutylamine; cyclohexylamine, dicyclohexylamine and the like. Alicyclic monoamines; examples include aromatic monoamines such as aniline, toluidine, diphenylamine, and naphthylamine. These can be used in combination of two or more. Of these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are more preferable from the viewpoints of reactivity, boiling point, stability of sealing end, price, and the like.

The amount of terminal amino groups can be measured by the following method.
As for the amount of terminal amino groups of the aliphatic polyamide [I], 0.5 to 0.7 g of the aliphatic polyamide [I] is precisely weighed and dissolved in 30 mL of m-cresol. Then, 1 to 2 drops of a 0.1% Timorblue / m-cresol solution as an indicator is added to prepare a sample solution. The sample solution is titrated with a 0.02 specified p-toluenesulfonic acid solution from yellow to bluish purple to specify the terminal amino group content ([NH ₂ ], unit: μ equivalent / g).

The melting point (Tm) measured by differential scanning calorimetry (DSC) of the aliphatic polyamide [I] is preferably 200 to 290 ° C, more preferably 220 to 280 ° C. When the aliphatic polyamide [I] has such a melting point (Tm), a molded product having good heat resistance can be obtained without impairing the moldability.

The heat of fusion (ΔH) measured by differential scanning calorimetry (DSC) of the aliphatic polyamide [I] is preferably 45 to 100 mJ / mg. When the heat of fusion (ΔH) is 45 mJ / mg or more, the molded product tends to have sufficient oil resistance and heat resistance, and when it is 100 mJ / mg or less, the molded product becomes excessively hard (excessive elastic modulus). It can be suppressed.

The melting point (Tm) and heat of fusion (ΔH) of the aliphatic polyamide [I] can be measured under the following conditions.
Using DSC (Differential Scanning Calorimetry), the polyamide [I] is heated and held at 320 ° C. for 5 minutes, then cooled to 23 ° C. at a rate of 10 ° C./min, and then at 10 ° C./min. The temperature rises at a rate. The temperature of the endothermic peak based on melting at this time is defined as the melting point (Tm) of the polyamide. Further, the amount of heat of fusion (ΔH) (mJ / mg) is calculated from the area separated by the endothermic peak of the obtained curve and the baseline of the entire endothermic peak.

The melting point and heat of fusion (ΔH) of the aliphatic polyamide [I] can be adjusted by, for example, the monomer composition constituting the aliphatic polyamide [I]. In order to increase the melting point and the calorific value (ΔH) of the aliphatic polyamide [I], for example, the carbon number of the dicarboxylic acid, diamine, aminocarboxylic acid or lactam constituting the aliphatic polyamide [I] may be kept below a certain level. preferable.

The melt flow rate (MFR) of the aliphatic polyamide [I] according to ISO 1133 at 290 ° C. and a load of 2.16 kg is adjusted with the viscosity of the copolymer rubber [II] at the time of compounding to facilitate microdispersion. , 0.1 to 500 g / 10 minutes, more preferably 0.1 to 300 g / 10 minutes, 0.1 to 100 g / 10 minutes, and 1 to 100 g / 10 minutes. In particular, from the viewpoint of facilitating the reduction in the particle size of the dispersed phase containing the copolymer rubber [II] as a main component, the melt flow rate (MFR) of the aliphatic polyamide [I] is preferably not more than a certain level.

As described above, the aliphatic polyamide [I] can be produced by subjecting a dicarboxylic acid and a diamine to a polycondensation reaction, an aminocarboxylic acid to a polycondensation reaction, or a lactam by a ring-opening polymerization reaction. it can. Further, as described above, at least a part of the terminal groups of the molecular chain of the aliphatic polyamide [I] may be sealed with an end-capping agent.

The amount of the terminal encapsulant used in producing the aliphatic polyamide [I] is preferably determined from the relative viscosity of the finally obtained aliphatic polyamide [I] and the encapsulation rate of the end group. The specific amount used varies depending on the reactivity of the terminal encapsulant used, boiling point, reactor, reaction conditions, etc., but is usually 0.3 to 10 mol based on the total number of moles of the raw materials dicarboxylic acid and diamine. It can be in the range of%.

The content of the aliphatic polyamide [I] is preferably 10 to 60% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component. When the content of the aliphatic polyamide [I] is 10% by mass or more, the content ratio of the matrix phase composed of the aliphatic polyamide [I] is high, so that sufficient heat resistance and oil resistance are imparted to the molded product. It is easy, and when it is 60% by mass or less, the flexibility of the molded product is not easily impaired. The content of the aliphatic polyamide [I] is more preferably 20 to 60% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component, and 25 to 60%. It is more preferably mass%.

1-2. Ethylene / α-olefin / non-conjugated polyene copolymer rubber [II]
The ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] contains an ethylene structural unit [a], an α-olefin structural unit [b] having 3 to 20 carbon atoms, and a non-conjugated polyene structural unit [c]. ] And is a copolymer rubber containing.

(Ethylene structural unit [a])
The content ratio of the ethylene structural unit [a] is preferably 50 to 89% by mass, more preferably 55 to 83% by mass, based on the total structural units constituting the copolymer rubber [II].

(Α-olefin structural unit [b] having 3 to 20 carbon atoms)
Examples of α-olefins having 3 to 20 carbon atoms constituting the copolymer rubber [II] include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-heptene. , 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-eicosen and the like. Of these, α-olefins having 3 to 8 carbon atoms such as propylene, 1-butene, 1-hexene, and 1-octene are preferable. The α-olefin may be one kind or a combination of two or more kinds. These α-olefins [b] are preferable because the raw material cost is relatively low and the copolymerizability is excellent, and the copolymer rubber [II] is provided with excellent mechanical properties and good flexibility.

The content ratio of the α-olefin structural unit [b] having 3 to 20 carbon atoms is preferably 10 to 49% by mass with respect to all the structural units constituting the copolymer rubber [II], and is preferably 15 to 43. More preferably, it is by mass%.

(Non-conjugated polyene structural unit [c])
The non-conjugated polyene constituting the copolymer rubber [II] is a non-conjugated polyene having at least one carbon-carbon double bond in one molecule that can be polymerized by a metallocene-based catalyst, and an example thereof is an aliphatic polyene. Includes polyenes and aliphatic polyenes.

Examples of aliphatic polyenes include 1,4-hexadiene, 1,5-heptadiene, 1,6-octadiene, 1,7-nonadien, 1,8-decadien, 1,12-tetradecadien, 3-methyl-. 1,4-Hexadien, 4-Methyl-1,4-Hexadien, 5-Methyl-1,4-Hexadien, 4-Ethyl-1,4-Hexadien, 3,3-Dimethyl-1,4-Hexadien, 5- Methyl-1,4-heptadiene, 5-ethyl-1,4-heptadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 5-ethyl-1,5-heptadiene, 4- Methyl-1,4-octadien, 5-methyl-1,4-octadien, 4-ethyl-1,4-octadien, 5-ethyl-1,4-octadien, 5-methyl-1,5-octadien, 6- Methyl-1,5-octadien, 5-ethyl-1,5-octadien, 6-ethyl-1,5-octadien, 6-methyl-1,6-octadien, 7-methyl-1,6-octadien, 6- Ethyl-1,6-octadien, 6-propyl-1,6-octadien, 6-butyl-1,6-octadien, 4-methyl-1,4-nonadien, 5-methyl-1,4-nonadien, 4- Ethyl-1,4-nonadien, 5-ethyl-1,4-nonadien, 5-methyl-1,5-nonadien, 6-methyl-1,5-nonadien, 5-ethyl-1,5-nonadien, 6- Ethyl-1,5-nonadien, 6-methyl-1,6-nonadien, 7-methyl-1,6-nonadien, 6-ethyl-1,6-nonadien, 7-ethyl-1,6-nonadien, 7- Methyl-1,7-nonadien, 8-methyl-1,7-nonadien, 7-ethyl-1,7-nonadien, 5-methyl-1,4-decadien, 5-ethyl-1,4-decadien, 5- Methyl-1,5-decadien, 6-methyl-1,5-decadien, 5-ethyl-1,5-decadien, 6-ethyl-1,5-decadien, 6-methyl-1,6-decadien, 6- Ethyl-1,6-decadien, 7-methyl-1,6-decadien, 7-ethyl-1,6-decadien, 7-methyl-1,7-decadien, 8-methyl-1,7-decadien, 7- Ethyl-1,7-decadien, 8-ethyl-1,7-decadien, 8-methyl-1,8-decadien, 9-methyl-1,8-decadien, 8-ethyl-1,8-decadien, 6- Methyl-1,6-Undeca Includes α, ω-diene such as diene, 9-methyl-1,8-undecadiene, and further 1,7-octadiene, 1,9-decadiene. Of these, 7-methyl-1,6-octadien is preferred.

Examples of alicyclic polyenes include 5-ethylidene-2-norbornene (ENB), 5-propyriden-2-norbornene, 5-butylidene-2-norbornene, 5-vinyl-2-norbornene (VNB); 5-allyl. 5-alkenyl-2-norbornene such as -2-norbornene; 2,5-norbornadiene, dicyclopentadiene (DCPD), norbornadiene, tetracyclo [4,4,0,12.5,17.10] deca-3,8 -Diene, 2-methyl-2,5-norbornadiene, 2-ethyl-2,5-norbornadiene and the like are included. Of these, 5-ethylidene-2-norbornene (ENB) is preferable. The non-conjugated polyene structural unit [c] may be of one type or in combination of two or more types.

The content ratio of the non-conjugated polyene structural unit [c] is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, based on all the structural units constituting the copolymer rubber [II]. preferable.

The ultimate viscosity [η] of the copolymer rubber [II] is preferably 0.5 to 5.0 dl / g, more preferably 1.0 to 4.5 dl / g, and 1.5 to 4.5 dl / g. It is particularly preferably 4.0 dl / g. This ultimate viscosity [η] is a value measured in decalin at a temperature of 135 ° C., and can be determined by measuring according to ASTM D 1601.

The content of the copolymer rubber [II] is preferably 33 to 86% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component. When the content of the copolymer rubber [II] is 33% by mass or more, it is easy to impart sufficient flexibility to the molded product, and when it is 86% by mass or less, the heat resistance and oil resistance of the molded product are impaired. Hateful. The content of the copolymer rubber [II] is more preferably 33 to 55% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component, and the copolymer weight From the viewpoint of making it easier to finely disperse the dispersed phase containing the coalesced rubber [II], further suppressing the decrease in storage elastic modulus at high temperature, and further improving the oil resistance, the content is 33 to 50% by mass. Is more preferable, and 33 to 40% by mass is particularly preferable.

The mass ratio ([II] / [I]) of the copolymer rubber [II] and the aliphatic polyamide [I] makes it easy to finely disperse by matching the viscosities of both at the time of compounding, and has a good 10 MPa storage elastic modulus. From the viewpoint of facilitating the maintenance temperature and oil resistance, for example, it is preferably 20/80 to 70/30, and more preferably 30/70 to 60/40. When the mass ratio of the copolymer rubber [II] is above a certain level, it is easy to impart sufficient flexibility to the molded product, and when the mass ratio of the copolymer rubber [II] is below a certain level, the grains of the dispersed phase The diameter can be easily reduced, and the maintenance temperature and oil resistance of the 10 MPa storage elastic modulus are not easily impaired.

1-3. Olefin-based polymer [III]
The olefin-based polymer [III] is an olefin-based polymer containing 0.3 to 5.0% by mass of a functional group structural unit. The functional group structural unit is a structural unit derived from a compound having a functional group or a monomer having a functional group. Examples of functional groups in the functional group structural unit include carboxylic acid groups (including acid anhydride groups), ester groups, ether groups, aldehyde groups, ketone groups and the like. The olefin-based polymer [III] having such a functional group structural unit has an affinity with the aliphatic polyamide [I] by having a functional group, and has a copolymer rubber by having an olefin-based skeleton. Since it has an affinity with [III], the compatibility between the two can be enhanced.

The olefin polymer [III] is obtained by copolymerizing a modified polyolefin [III] -1, which has a functional group introduced into a polyolefin molecular chain by reacting a compound having a functional group, and an olefin monomer and a monomer having a functional group. The functional group-containing olefin copolymer [III] -2 to be used is contained.

Examples of polyolefins constituting modified polyolefin [III] -1 are homopolymers or copolymers of olefins having 2 to 18 carbon atoms, and examples thereof include low-density polyethylene, medium-density polyethylene, and high-density polyethylene. , Polypropylene, ethylene / α-olefin copolymers are included. Of these, an ethylene / α-olefin copolymer is preferable. The α-olefin in the ethylene / α-olefin copolymer is preferably an α-olefin having 3 to 10 carbon atoms, and examples thereof include propylene and 1-butene. Examples of ethylene / α-olefin copolymers include ethylene-propylene copolymers and ethylene-butene copolymers.

Examples of compounds having a functional group constituting the modified polyolefin [III] -1 include unsaturated carboxylic acids having a functional group or derivatives thereof. Examples of functionally unsaturated carboxylic acids or derivatives thereof include acrylic acid, methacrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, endosis. -Unsaturated carboxylic acids such as bicyclo [2,2,1] hepto-5-ene-2,3-dicarboxylic acid (nagic acid), and derivatives of these acid halides, amides, imides, acid anhydrides, esters, etc. Can be mentioned. Of these, unsaturated dicarboxylic acids or acid anhydrides thereof are preferable, maleic acid, nadic acid or acid anhydrides thereof are more preferable, and maleic anhydride is particularly preferable. Maleic anhydride has a relatively high reactivity with the polyolefin before modification, polymerization of maleic anhydride with each other is unlikely to occur, and the basic structure tends to be stable. Therefore, stable quality modified polyolefin [III] -1 can be easily obtained.

Examples of modified polyolefin [III] -1 include modified ethylene / α-olefin copolymers. The density of the modified ethylene / α-olefin copolymer is preferably 0.80 to 0.95 g / cm ³ , and more preferably 0.85 to 0.90 g / cm ³ .

The olefin monomer constituting the functional group-containing olefin copolymer [III] -2 is preferably an olefin monomer having 2 to 18 carbon atoms, and examples thereof include ethylene and propylene, preferably ethylene. is there.

Examples of the monomer having a functional group constituting the functional group-containing olefin copolymer [III] -2 include an acrylic monomer, a vinyl monomer and the like.

Examples of the functional group-containing olefin copolymer [III] -2 include ethylene / vinyl acetate / maleic anhydride copolymer (Orevac® manufactured by Alchema), ethylene / acrylic ester / functional acrylic. An acid ester (for example, glycidyl acrylate or glycidyl methacrylate) copolymer (Lotader (registered trademark) manufactured by Alchema, etc.) is included.

The content of the functional group structural unit of the olefin polymer [III] is preferably 0.3 to 5.0% by mass, more preferably 0.4 to 4.0% by mass. When the functional group structural unit is 0.3% by mass or more, not only the dispersibility of the ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] with respect to the aliphatic polyamide [I] is easily improved, but also the mechanical Target strength is not easily impaired. On the other hand, when the functional group structural unit is 5.0% by mass or less, an excessive reaction with the aliphatic polyamide [I] is unlikely to occur, so that the melt fluidity is unlikely to be lowered due to gelation, and the moldability is impaired. Hateful.

The content of the functional group structural unit is the content of the compound having a functional group or the structural unit derived from the monomer having a functional group with respect to the total mass of the structural units derived from the monomer having no functional group constituting the olefin polymer [III]. Percentage (% by mass).

The content of the functional group structural unit of the olefin polymer [III] ^{can be measured by 13} C-NMR measurement or ¹ H-NMR measurement. The specific measurement conditions are as follows.

^{1 For 1} H-NMR measurement, use an ECX400 type nuclear magnetic resonance device manufactured by JEOL Ltd., use deuterated orthodichlorobenzene as the solvent, sample concentration is 20 mg / 0.6 mL, measurement temperature is 120 ° C, and observation is performed. The nucleus is ¹ H (400 MHz), the sequence is a single pulse, the pulse width is 5.12 μsec (45 ° pulse), the repetition time is 7.0 seconds, and the number of integrations is 500 or more. In the standard chemical shift, the hydrogen content of tetramethylsilane is set to 0 ppm. For example, the same result can be obtained by setting the peak derived from residual hydrogen of deuterated orthodichlorobenzene to 7.10 ppm and using it as the reference value for the chemical shift. be able to. Peaks such as 1H derived from functional group-containing compounds can be assigned by a conventional method.

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

The ultimate viscosity [η] of the olefin polymer [III] measured in a 135 ° C. decalin (decahydronaphthalene) solution is preferably 0.5 to 4.0 dl / g, preferably 0.7 to 3. It is more preferably 0 dl / g, and even more preferably 0.8 to 2.5 dl / g. When [η] is within the above range, the melt fluidity of the resin composition and the toughness of the obtained molded product can be compatible at a high level.

The ultimate viscosity [η] of the olefin polymer [III] can be measured by the following method based on a conventional method.
20 mg of the sample is dissolved in 15 ml of decalin, and the specific viscosity (ηsp) is measured in an atmosphere of 135 ° C. using an Ubbelohde viscometer. Further, 5 ml of decalin is added to this decalin solution to dilute it, and then the same specific viscosity measurement is performed. Based on the measurement result of repeating this dilution operation and the viscosity measurement twice more, the "ηsp / C" value when the concentration (: C) is extrapolated to zero is defined as the ultimate viscosity [η].

Examples of commercially available products of the olefin polymer [III] include Toughmer series (maleic anhydride-modified ethylene-propylene rubber, maleic anhydride-modified ethylene-butene rubber, etc.) of Mitsui Chemicals Co., Ltd., and Admer (maleic anhydride-modified). Polypropylene, maleic anhydride-modified polyethylene); Claret (maleic anhydride-modified isoprene rubber, maleic anhydride-modified isoprene rubber), Septon (maleic anhydride-modified SEPS); Nuclel of Mitsui DuPont Polychemical Co., Ltd. (Ethethylene-methacrylic acid copolymer), HPR (maleic anhydride-modified EEA, maleic anhydride-modified EVA); Royaltub (maleic anhydride-modified EPDM) from Chemtura; Clayton FG (maleic anhydride-modified SEBS) from Kraton; JX Nikko Nisseki Energy Co., Ltd. Nisseki Polybutene (maleic anhydride-modified polybutene); Arkema Bondine (maleic anhydride-modified EEA); Asahi Kasei Co., Ltd. Tough Tech M (maleic anhydride-modified SEBS); Nippon Polyethylene (Nippon Polyethylene) Lexpar ET (maleic anhydride-modified EEA); Modic (maleic anhydride-modified EVA, maleic anhydride-modified polypropylene, maleic anhydride-modified polyethylene) of Mitsubishi Chemical Co., Ltd .; Bond First (maleic anhydride-modified polyethylene) of Sumitomo Chemical Co., Ltd. E-GMA); LANXESS's Clinac (carboxy-modified nitrile rubber); Nippon Paper Co., Ltd.'s aurolen (maleic anhydride-modified EEA) and the like are included (all of these are trade names). These may be used alone or in combination of two or more.

The content of the olefin polymer [III] is preferably 0.1 to 30% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component. When the content of the olefin polymer [III] is 0.1% by mass or more, the compatibility between the [I] component and the [II] component can be sufficiently enhanced, so that the molded product has sufficient mechanical strength. It is easy to apply, and when it is 30% by mass or less, the characteristics of the [I] component and the [II] component are not easily impaired. The content of the olefin polymer [III] is more preferably 3 to 30% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component. It is more preferably 20% by mass.

The mass ratio ([III] / [II]) of the olefin polymer [III] and the copolymer rubber [II] is preferably 1/500 to 1/1. When the mass ratio of the olefin polymer [III] is more than a certain level, the compatibility between the aliphatic polyamide [I] and the copolymer rubber [II] is not easily impaired, so that sufficient mechanical strength is imparted to the molded product. It is easy to do, and when it is below a certain level, the characteristics of the aliphatic polyamide [I] and the copolymer rubber [II] are not easily impaired. The mass ratio of the olefin polymer [III] to the copolymer rubber [II] is more preferably 1/20 to 1/1, and even more preferably 1/20 to 1/2.

1-4. Phenol resin-based cross-linking agent [IV]
The phenol resin-based cross-linking agent is typically a resole resin obtained by condensing an alkyl-substituted or unsubstituted phenol with an aldehyde (preferably formaldehyde) in the presence of an alkali catalyst. The alkyl group of the alkyl-substituted phenol is preferably an alkyl group having 1 to 10 carbon atoms. In particular, dimethylolphenols or phenol resins substituted with alkyl groups having 1 to 10 carbon atoms are preferable.

Examples of the phenol resin-based cross-linking agent include a compound represented by the following formula [IV-1].

In the formula [IV-1], R is an organic group such as an alkyl group, preferably an organic group having less than 20 carbon atoms, and more preferably an organic group having 4 to 12 carbon atoms. R'is a hydrogen atom or -CH _2- OH. n and m are integers of 0 to 20, preferably an integer of 0 to 15, and more preferably an integer of 0 to 10.

Other examples of the phenol resin-based cross-linking agent include a methylolated alkylphenol resin and a halogenated alkylphenol resin. The halogenated alkylphenol resin is an alkylphenol resin in which the hydroxyl group at the end of the molecular chain is replaced with a halogen atom such as bromine, and examples thereof include compounds represented by the following formula [IV-2].

N, m and R in the formula [IV-2] are synonymous with n, m and R in the formula [IV-1], respectively. R'in formula [IV-2] is a hydrogen atom, -CH ₃ or -CH _2- Br.

Examples of commercially available phenolic resin-based cross-linking agents include Tacki Roll 201, Tacky Roll 250-I, Tacky Roll 250-III from Taoka Chemical Industry Co., Ltd .; SP1045, SP1055, SP1056 from SI Group; Showa Denko Co., Ltd. Noor CRM; Tamanor 531 of Arakawa Chemical Industry Co., Ltd .; Sumitomo Bakelite Co., Ltd.'s Sumilite Resin PR; Gun Ei Chemical Industry Co., Ltd.'s cash register top (all trade names) are included. These may be used alone or in combination of two or more. Of these, Tackylol 250-III (brominated alkylphenol formaldehyde resin) manufactured by Taoka Chemical Industry Co., Ltd. and SP1055 (brominated alkylphenol formaldehyde resin) manufactured by SI Group are preferable.

Of these, halogenated alkylphenol resins are particularly preferred. The halogen alkylphenol resin is preferable because it has excellent compatibility with the copolymer rubber [II] and is highly reactive, and the cross-linking reaction start time can be relatively short.

When the phenol resin-based cross-linking agent [IV] is a powder-like cross-linking agent, its average particle size is preferably 0.1 μm to 3 mm, more preferably 1 μm to 1 mm, and particularly preferably 5 μm to 0.5 mm. .. The flake-shaped curing agent is preferably used after being powdered by a crusher such as a jet mill or a crusher with a crushing blade.

The content of the phenolic resin-based cross-linking agent [IV] is preferably 1 to 10% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component. When the content of the phenol resin-based cross-linking agent [IV] is 1% by mass or more, it is easy to sufficiently crosslink the [II] component and the like, so that it is easy to impart sufficient heat resistance and oil resistance to the molded product, and the phenol resin. When the content of the system cross-linking agent [IV] is 10% by mass or less, the characteristics of the [I] component and the [II] component are not easily impaired. The content of the phenolic resin-based cross-linking agent [IV] is more preferably 1 to 8% by mass with respect to the total of the [I] component, the [II] component, the [III] component and the [IV] component. It is more preferably 2 to 6% by mass.

1-5. Crosslinking aid [V]
The cross-linking aid [V] is preferably a zinc compound. The zinc compound is ^{a zinc salt having a Zn + 2} cation and a negatively charged counterion. The negative charge counterion is non-toxic and is preferably a thermally stable negative charge counterion at least about 200 ° C. or lower, and is preferably a thermally stable negative charge counterion at least 300 ° C. or lower. More preferred.

The zinc compound has a molecular weight of about 1000 or less including ^{Zn 2+ cations and negatively charged counterions.} Examples of zinc compounds include zinc carboxylate, zinc carbonate, zinc titanate, zinc molybdenate, zinc sulfate, zinc phosphate, zinc oxide, zinc borate and zinc halide. Examples of zinc halides include zinc iodide. Examples of zinc carboxylate include zinc acetate, zinc stearate, zinc oxalate, zinc palmitate, zinc 2-ethylhexanoate, zinc gluconate, zinc laurate, zinc salicylate, zinc terephthalate, zinc isophthalate, phthalate. Includes zinc acid acid, zinc succinate, zinc adipate, zinc pyromellitic acid, zinc benzenetricarboxylate, zinc butanetetracarboxylate and zinc trifluoromethanesulfonate. Among these, one or more selected from the group consisting of zinc oxide, zinc carbonate, zinc carboxylate, zinc hydroxide and combinations thereof is preferable, the cross-linking reaction rate can be easily increased, and the obtained dispersed phase is finely dispersed. Zinc oxide is more preferable from the viewpoint of facilitating the production.

The content of the cross-linking aid [V] (zinc compound) is such that the mass ratio [V] / [I] of the cross-linking aid [V] (zinc compound) to the aliphatic polyamide [I] is 0.0001 to 0. It is set to 02, preferably 0.0003 to 0.01, more preferably 0.0004 to 0.01, and even more preferably 0.0004 to 0.009. When the mass ratio [V] / [I] is 0.0001 or more, insufficient cross-linking is unlikely to occur. Therefore, the particle size of the dispersed phase containing the copolymer rubber [II] and the olefin polymer [III] as main components. Does not become too large (it is easy to finely disperse the dispersed phase). As a result, the maintenance temperature of the storage elastic modulus of the polyamide-based thermoplastic elastomer composition is unlikely to be lowered, and the oil resistance is unlikely to be lowered. When the mass ratio [V] / [I] is 0.02 or less, the cross-linking rate does not become too high, and the copolymer rubber [II] is easily cross-linked after being sufficiently finely dispersed. The particle size of the dispersed phase containing rubber [II] as a main component does not become too large (it is easy to finely disperse the dispersed phase). As a result, the maintenance temperature of the storage elastic modulus of the polyamide-based thermoplastic elastomer composition is unlikely to be lowered, and the oil resistance is unlikely to be lowered.

The total content of the [I] component, the [II] component, the [III] component, the [IV] component and the [V] component is preferably 80% by mass or more, preferably 90% by mass or more, based on the total mass of the rubber composition. It is more preferably mass% or more, and may be 100 mass%.

1-6. Other Components The rubber composition for obtaining the polyamide-based thermoplastic elastomer composition may further contain other components, if necessary, as long as the effects of the present invention are not impaired. Examples of other components include cross-linking agents other than the phenol-resin-based cross-linking agent [IV], cross-linking aids, plasticizers, antioxidants, colorants, antistatic agents (conductive agents), fillers, and the like. Is done.

The other cross-linking agent may be any cross-linking agent capable of dynamically cross-linking the rubber composition described above, and examples thereof include sulfur-based cross-linking agents. However, other cross-linking agents preferably do not contain organic peroxides. When an organic peroxide is used as another cross-linking agent, the decomposition rate of the organic peroxide may become too fast because the melt-kneading temperature suitable for the polyamide-based thermoplastic elastomer composition of the present invention is relatively high. is there. As a result, the cross-linking reaction of the rubber component ([II] component, [III] component) tends to proceed rapidly, and it may not be sufficiently kneaded with the aliphatic polyamide [I], resulting in insufficient dispersion. Therefore, the physical characteristics of the polyamide-based thermoplastic elastomer composition may be significantly deteriorated.

Further, the rubber composition for obtaining the polyamide-based thermoplastic elastomer composition is a polyamide other than the above-mentioned aliphatic polyamide [I] as long as the effect of the present invention is not impaired (hereinafter, also referred to as “other polyamide”). May further be included. Examples of other polyamides include polyamide 11, polyamide 12, aromatic polyamide and the like. The polyamide-based thermoplastic elastomer composition may contain one kind of these other polyamides, or may contain two or more kinds of them.

2. Method for Producing Polyamide-based Thermoplastic elastomer Composition The polyamide-based thermoplastic elastomer composition of the present invention comprises the above-mentioned aliphatic polyamide [I], ethylene / α-olefin / non-conjugated polyene copolymer rubber [II], and the above-mentioned aliphatic polyamide [I]. Dynamically cross-linking at least a part of a rubber composition containing an olefin polymer [III], a phenol resin-based cross-linking agent [IV], and a zinc compound as a cross-linking aid [V], specifically. It can be obtained by cross-linking in a molten flow state (dynamic state).

Such a dynamic cross-linking reaction is usually carried out by supplying the above-mentioned composition to a melt-kneading apparatus and heating it to a predetermined temperature for melt-kneading.

In the melt kneading, the [I] component, the [II] component, the [III] component, the [IV] component and the [V] component may be kneaded at the same time; the [I] component, the [II] component and the [III] component. After kneading the component and the [V] component, the [IV] component may be added and further kneaded.

As the melt-kneading device, for example, a twin-screw extruder, a single-screw extruder, a kneader, a Banbury mixer and the like can be used. Among them, a twin-screw extruder is preferable from the viewpoint of good shearing force and continuous productivity. The melt-kneading temperature is usually 200 to 320 ° C. The melt-kneading time is usually 0.5 to 30 minutes.

By this dynamic cross-linking, the ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] is cross-linked in the polyamide-based thermoplastic elastomer composition. That is, the polyamide-based thermoplastic elastomer composition contains an aliphatic polyamide [I], a copolymer rubber [II] crosslinked with a phenol resin-based cross-linking agent [IV], and a functional group structural unit of 0.3 to 5. It may contain an olefin polymer [III] containing 0.0% by mass and a cross-linking aid [V]. Then, the sea phase (matrix phase) containing the aliphatic polyamide [I] as the main component, the crosslinked copolymer rubber [II], and the island phase (dispersion) containing the olefin polymer [III] as the main components. A sea-island structure having a phase) is formed. The marine phase (matrix phase) containing the aliphatic polyamide [I] as a main component can exhibit thermoplasticity. On the other hand, the crosslinked copolymer rubber [II] and the island phase (dispersed phase) containing the olefin polymer [III] as main components can exhibit rubber elasticity. The average particle size of the island phase (dispersed phase) is relatively small and is finely dispersed.

As described above, the polyamide-based thermoplastic elastomer composition is finely dispersed in the matrix component (sea phase) containing the aliphatic polyamide [I] as a main component and the matrix phase (sea phase), and the copolymer rubber [ It has a dispersed phase (island phase) containing II] and an olefin polymer [III] as main components.

The average particle size of the dispersed phase (island phase) is preferably 0.3 μm or more and 5.0 μm or less, more preferably 0.3 μm or more and 2.5 μm or less, and 0.3 μm or more and 1.5 μm or less. It is more preferable to have.

Then, in the image obtained by the TEM measurement, the area of the dispersed phase having a particle size of 3.0 μm or more is measured, and the ratio of the cumulative area of the dispersed phase to the total area of the analyzed region is 10% or less. Is more preferable, 8% or less is more preferable, 6% or less is further preferable, and 3% or less is particularly preferable.

When the ratio of the cumulative cross-sectional area of the dispersed phase (dispersed phase group (A)) having a particle size of 3.0 μm or more to the entire area of the analyzed region is 10% or less, the oil resistance tends to be particularly high. Further, when the ratio of the cumulative cross-sectional area of the dispersed phase (dispersed phase group (A)) having a particle size of 3.0 μm or more is 6% or less and further 3% or less, the maintenance temperature of the storage elastic modulus of 10 MPa is further lowered. It is easier to suppress, especially when the cumulative cross-sectional area ratio is 0%, that is, when there is no large dispersed phase group of 3.0 μm or more, the elastic modulus is maintained even at high temperatures while having flexibility at room temperature. However, it tends to be excellent in both high oil resistance.

The TEM measurement can be performed by the following method.
First, a polyamide-based thermoplastic elastomer composition is extruded to prepare a test piece. The prepared test piece is ground with a microtome or the like, and the obtained range of an arbitrary cross section of about 45 μm × 75 μm or more is 3,000 times larger using a transmission electron microscope (measuring device: H-7650 manufactured by Hitachi High-Technology Co., Ltd.). Enlarge and analyze. The analysis is performed by binarizing using the image analysis software ImageJ.

1A and 1B are TEM photographs of the cut surface of the polyamide-based thermoplastic elastomer composition according to the embodiment of the present invention. FIG. 1A is a TEM photograph observed at a magnification of 3000, and FIG. 1B is a TEM photograph observed at a magnification of 10000.

As shown in FIG. 1, a matrix phase containing an aliphatic polyamide [I] as a main component (a portion whiter in color than the other part of FIG. 1, a matrix component) and an ethylene / α-olefin / non-conjugated polyene copolymer. The occupied areas of the dispersed phase containing the rubber [II] and the olefin polymer [III] as the main components (the portion darker in color than the other portion in FIG. 1 and the dispersed component) are specified.
Image analysis is performed for each occupied area of the identified dispersed phase, and the area is calculated.
Then, the diameter of a perfect circle having an area equal to that area is obtained, and the arithmetic mean of the values obtained for each occupied area is used as the average particle size of the dispersed phase.
That is, for the particle size of each dispersed phase, the area S of each dispersed phase is obtained in the obtained image, and S is used to set (4S / π) × 0.5 as the particle size of each dispersed phase.

The average particle size in this embodiment is measured for a dispersed phase having a particle size of 0.3 μm or more (referred to as a dispersed phase group (A). The reason is that the dispersion has a particle size of less than 0.3 μm. The phase (referred to as the dispersed phase group (B)) has an area ratio of less than 1% in the total dispersed phase (or all particles), and includes a large number of particles of external additives that exist independently. This is because it is considered that there is almost no effect on the oil resistance of the embodiment.

The sheet-shaped or tube-shaped molded product obtained from such a polyamide-based thermoplastic elastomer composition has a matrix phase containing an aliphatic polyamide [I] as a main component, a copolymer rubber [II], and an olefin-based polymer. The morphology having a dispersed phase containing [III] as a main component (mainly a crosslinked rubber component) is controlled, and the dispersed phase is finely dispersed in the matrix phase. As a result, it has flexibility at room temperature, little decrease in elastic modulus even at high temperature, and high oil resistance.

The control of morphology can be adjusted mainly by the viscosity balance between the aliphatic polyamide [I] and the copolymer rubber [II], the cross-linking reaction rate, and the like. Specifically, the viscosity balance between the aliphatic polyamide [I] and the copolymer rubber [II] is, for example, the MFR of the aliphatic polyamide [I] or the copolymer rubber [II] and the aliphatic polyamide [I]. It can be adjusted by the mass ratio or the like. The cross-linking reaction rate can be adjusted by, for example, the type of the cross-linking agent [IV], the type and amount of the cross-linking aid [V], and the like.
Therefore, in order to facilitate fine dispersion of the dispersed phase having a small particle size, for example, the MFR of the aliphatic polyamide [I] is preferably small, and the mass ratio of the copolymer rubber [II] is not too large. Is preferable, a halogenated phenol resin is preferably selected as the cross-linking agent [IV], zinc oxide having a high reaction rate is preferably selected as the cross-linking aid [V], and the content of the cross-linking aid [V] is high. It is preferable to adjust to an appropriate range.

3. 3. Molded article and its use The molded article obtained by molding the above-mentioned polyamide-based thermoplastic elastomer composition can be used for various purposes, for example, automobile parts, building material parts, sporting goods, medical equipment parts, industrial parts and the like. , It is useful as a molded product for various purposes.

Above all, the molded product obtained from the above-mentioned polyamide-based thermoplastic elastomer composition has a high oil resistance while suppressing a decrease in elastic coefficient in a high temperature range, maintaining an appropriate viscosity when the resin is melted, and having high oil resistance. Therefore, it is suitable for a hollow molded body (industrial tube) and a molded body obtained by a specific molding method (blow molding, two-color molding, etc.).

<Hollow molded body (industrial tube)>
The industrial tube contains at least a layer containing the above-mentioned polyamide-based thermoplastic elastomer composition. Industrial tubing means tubing specifically used in industrial equipment. Examples of industrial tubes include tubes through which fluids (fuel, solvent, chemicals, gas, etc.) required for industrial equipment such as vehicles (for example, automobiles), pneumatic / hydraulic equipment, painting equipment, and medical equipment are passed. In particular, it is very useful in applications such as vehicle piping tubes (for example, fuel system tubes, intake system tubes, cooling system tubes), pneumatic tubes, hydraulic tubes, paint spray tubes, medical tubes (for example, catheters) and the like.

<Molded product obtained by injection molding, blow molding or two-color molding>
The molded product obtained by injection molding, blow molding or two-color molding can be widely used in various applications (for example, automobiles and electric products) in which such physical characteristics are required. Examples of molded parts obtained by injection molding, blow molding or two-color molding include constant velocity joint boots, boot parts such as dust covers, oil seals, gaskets, packings, dust covers, valves, stoppers, precision seal rubber, weather strips. And so on. Of these, constant velocity joint boots for automobiles are preferable. As a method for manufacturing constant velocity joint boots for automobiles, known methods such as an injection molding method and a blow molding method (injection blow molding method, press blow molding method) can be adopted.

Among these, the molded product obtained by molding the above-mentioned polyamide-based thermoplastic elastomer composition is a resin for intake / exhaust system parts that are automobile-related parts, constant velocity joint boots for automobiles, dust covers, various boot parts, and the like. It is particularly useful as a material for flexible boots, preferably as an intake / exhaust system component.

Examples of intake / exhaust system components include air hoses, air ducts, turbo ducts, turbo hoses, intake manifolds, exhaust manifolds, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples do not limit the scope of the invention to be construed.

1. 1. Material <Alphatic Polyamide [I]>
I-1: Polycaproamide (polyamide 6) (manufactured by Toray Industries, Inc., trade name Amylan "CM1046, melting point = 225 ° C., heat of fusion (ΔH) = 69 mJ / mg, terminal amine amount = 30 mmol / kg, MFR = 9 g / 10" Minutes)
I-2: Polyhexamethylene adipamide (polyamide 6/6) (manufactured by Toray Industries, Inc., trade name Amylan "CM3001-N", melting point = 265 ° C., heat of fusion (ΔH) = 74 mJ / mg, amount of terminal amine = 20 mmol / Kg, MFR = 90g / 10 minutes)
I-3: Polyhexamethylene adipamide (polyamide 6/6) (manufactured by DuPont, trade name zytel 101, melting point 265 ° C., heat of fusion (ΔH) = 69 mJ / mg, terminal amine amount = 41 mmol / kg, MFR = 65g / 10 minutes)
I-4: Polyhexamethylene decamide (polyamide 6/10) (manufactured by Toray Industries, Inc., trade name Amylan "CM2001, melting point = 225 ° C., heat of fusion (ΔH) = 83 mJ / mg, terminal amine amount = 18 mmol / kg, MFR = 250g / 10 minutes)
I-5: Polyhexamethylene decamide (polyamide 6/10) (manufactured by Arkema, trade name Hipprolon 70NN, melting point = 225 ° C., heat of fusion (ΔH) = 85 mJ / mg, terminal amine amount = 17 mmol / kg, MFR = 92 g / 10 minutes)
I-6: Polyhexamethylene decamide (polyamide 6/10) (manufactured by DuPont, trade name Zytel RSLC3060, melting point = 223 ° C., heat of fusion (ΔH) = 77 mJ / mg, terminal amine amount = 52 mmol / kg, MFR = 31g / 10 minutes)

<Comparison resin>
R-1: Polyamide elastomer (manufactured by Daicel Evonik, trade name Bestamide "E47-S4", melting point = 160 ° C)
R-2: Polyamide elastomer (manufactured by Daicel Evonik, trade name Bestamide "X4442", melting point = 170 ° C)
R-3: Polyamide 12 (with plasticizer) (manufactured by Arkema, trade name Rilsamide "AESNO P40 TL", melting point = 175 ° C)
R-4: Hexamethylenediamine and isophthalic acid salt / Hexamethylenediamine and terephthalic acid salt copolymer (manufactured by Mitsubishi Engineering Plastics, trade name polyamide MXD6 Lenny "# 6007", melting point = 243 ° C, Heat of fusion (ΔH) = 52 mJ / mg, amount of terminal amine = 9 mmol / kg, MFR = 23 g / 10 minutes)
R-5: Polyamide 12 (manufactured by Ube Industries, Ltd., trade name UBESTA3030U, melting point = 178 ° C., terminal amine amount = 18 mmol / kg, MFR = 9 g / 10 minutes)
R-6: Polyamide 6T6I66 (6T / 6I / 66 = 44/36/20)
Dicarboxylic acid component = 44% by mass of terephthalic acid, 36% by mass of isophthalic acid, 20% by mass of adipic acid
Diamine component = 1,6-hexanediamine Melting point (Tm) = 265 ° C
Amino group amount at the end of the molecular chain = 19 mmol / kg
The melting point, heat of fusion, terminal amine amount and MFR of these aliphatic polyamides [I] and the comparative resin are values measured by the above-mentioned methods, respectively.

<Ethylene / α-olefin / non-conjugated polyene copolymer rubber [II]>
As the copolymer rubber [II], ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber ([η] = 2.4 dl / g, ethylene content 65% by mass, diene content 4.6% by mass) was used. I prepared it.

<Olefin-based polymer [III]>
As the olefin polymer [III], a modified polyolefin synthesized as follows was prepared.

First, 0.63 mg of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride was placed in a glass flask fully substituted with nitrogen, and a toluene solution of methylaminoxane (Al: 0.13 mmol / liter) was used. 57 ml and 2.43 ml of toluene were further added to obtain a catalytic solution.
912 ml of hexane and 320 ml of 1-butene were introduced into a stainless steel autoclave having an internal volume of 2 liters sufficiently substituted with nitrogen, and the temperature in the system was raised to 80 ° C. Subsequently, 0.9 mmol of triisobutylaluminum and 2.0 ml of the above catalyst solution (0.0055 mmol as Zr) were press-fitted with ethylene to initiate polymerization.
^{The total pressure was maintained at 8.0 kg / cm 2-} G by continuously supplying ethylene, and polymerization was carried out at 80 ° C. for 30 minutes. After introducing a small amount of ethanol into the system to terminate the polymerization, unreacted ethylene was purged. A white solid was precipitated by pouring the resulting solution into a large excess of methanol.
This white solid was recovered by filtration and dried under reduced pressure overnight to obtain a white solid ethylene / 1-butene copolymer. The density of this ethylene / 1-butene copolymer is 0.862 g / cm ³ , the MFR (ASTM D1238 standard, 190 ° C., 2160 g load) is 0.5 g / 10 minutes, and the 1-butene structural unit content is 4. It was mol%.
100 parts by mass of this ethylene / 1-butene copolymer is mixed with 1.0 part by mass of maleic anhydride and 0.04 part by mass of peroxide (manufactured by Nichiyu Co., Ltd., trade name: Perhexin 25B). The above mixture was melt-grafted-modified with a uniaxial extruder set at 230 ° C. to obtain the above-mentioned maleic anhydride-modified ethylene / 1-butene copolymer.

The amount of maleic anhydride graft modification (content of functional group structural unit) of the obtained maleic anhydride-modified ethylene / 1-butene copolymer was 0.97% by mass, and the extreme viscosity measured in a decalin solution at 135 ° C. [ η] It was 1.98 dl / g. The content of the functional group structural unit ^{was measured by the above-mentioned 13} CNMR method, and the ultimate viscosity [η] was measured by the above-mentioned method.

<Unmodified olefin polymer>
Unmodified olefin polymer: The ethylene / 1-butene copolymer before modification obtained above.

<Phenol resin-based cross-linking agent [IV]>
As a phenol resin-based cross-linking agent [IV], flaky brominated alkylphenol formaldehyde resin (manufactured by Taoka Chemical Industry Co., Ltd., trade name Tackiroll 250-III) is stirred for 10 seconds with a Henshell mixer to form a powder. I prepared it.

<Comparison cross-linking agent>
Peroxide (manufactured by NOF CORPORATION, trade name Perhexin 25B)

<Crosslinking aid [V]>
HakusuiTech Co., Ltd., 2 types of zinc oxide, Shodo Chemical Industry Co., Ltd., Zinc Carbonate Nitto Kasei Kogyo Co., Ltd., Zinc stearate

2. Preparation of Polyamide-based Thermoplastic Elastomer Composition <Example 1>
Polyamide [I-1] 47% by mass, copolymer rubber [II] 40% by mass, olefin polymer [III] 10.47% by mass, phenol resin-based cross-linking agent [IV] 2.5% by mass and 0. A cross-linking aid (manufactured by Huxitec Co., Ltd., 2 types of zinc oxide) of 03% by mass (mass ratio [V] / [I] = 0.0006) was premixed, and this was mixed with a twin-screw extruder (Japan Co., Ltd.). It was supplied to TEX-30) manufactured by Japan Steel Works, and melt-kneaded at a cylinder temperature of 280 ° C. and a screw rotation speed of 300 rpm. The strands extruded from this twin-screw extruder were cut to obtain pellets of a polyamide-based thermoplastic elastomer composition.

<Examples 2 to 12, Reference Example 1, Comparative Examples 1 to 10>
Pellets of the polyamide-based thermoplastic elastomer composition were obtained in the same manner as in Example 1 except that the composition was changed to that shown in Table 1 or 2.

The storage elastic modulus E', oil resistance, mass change rate in the heat loss test, and TEM measurement of the test pieces molded using the pellets obtained in Examples 1 to 12, Reference Example 1 and Comparative Examples 1 to 10 were measured. , Each was measured by the following method.

[Storage modulus E']
(23 ° C storage elastic modulus E')
The obtained pellets were put into a press machine and hot-pressed under the conditions of press temperature: melting point + 25 ° C. to obtain a film (test piece) having a thickness of about 500 μm. The obtained film was set in DVA-225 manufactured by IT Measurement Control Co., Ltd., and the storage elastic modulus (E') was measured under the conditions of tensile mode, heating rate: 3 ° C./min, frequency: 1 Hz, and the specified temperature was determined. The storage elastic modulus (E') at (23 ° C.) was read.

(10 MPa maintenance temperature)
From the obtained storage elastic modulus (E'), the maximum temperature for maintaining 10 MPa was read and used as the 10 MPa maintenance temperature. Generally, if it is less than 10 MPa, deformation due to its own weight often occurs, and the shape of the molded product cannot be maintained.

[Oil resistance]
The oil resistance was evaluated in accordance with the JIS K6258 full-scale immersion test.
Specifically, the obtained pellets were put into a press machine and hot-pressed under the conditions of press temperature: melting point + 25 ° C. to obtain a square plate (test piece) having a thickness of 30 mm × 30 mm × thickness 2 mm.
The obtained film was immersed in IRM903 oil maintained at 120 ° C. or 175 ° C. for 72 hours according to JIS K6258, and then the mass change rate (mass%) was determined.

[Heat weight loss test]
(Mass change rate)
1) The obtained pellets were put into a press machine and hot-pressed under the conditions of press temperature: melting point + 25 ° C. to obtain a film (test piece) of 20 cm × 20 cm × thickness of about 500 μm. Then, the mass (M0) of this film was measured.
2) Next, it was held in a vacuum dryer under reduced pressure at 150 ° C. for 10 hours. Then, the mass (M1) of the film was measured again.
3) The mass change rate (mass%) was calculated by applying the masses of the films 1) and 2) to the following formulas, respectively.
Rate of change in mass (mass%) = (M0-M1) / M0 × 100

(Pre-test elastic modulus / Post-test elastic modulus)
In the same manner as the above-mentioned mass change rate, the storage elastic modulus of the film (test piece) after the heating test was measured by the same method as the above-mentioned storage elastic modulus E'.
Then, the ratio (post-test elastic modulus / pre-test elastic modulus) (%) of the storage elastic modulus E'after the heating test and the storage elastic modulus before the heating test (storage elastic modulus E'at 23 ° C.) was calculated.

[Transmission electron microscope (TEM) measurement]
The obtained pellets were ground with a microtome and ultrathin sections were trimmed. The cross section of the obtained ultrathin section was exposed to the vapor of ruthenium tetroxide for a certain period of time, and only the dispersed phase among the dispersed phase and the matrix phase was selectively stained. This was observed with a transmission electron microscope (TEM, H-7650 manufactured by Hitachi High-Technology Co., Ltd.) at a magnification of 3000. From the obtained TEM image, the average particle size of the stained dispersed phase (dispersed phase group (A)), the total area of the dispersed phase having a particle size of 3.0 μm or more, and the analysis area (the area of the area where the analysis was performed). Was calculated, and the ratio of the dispersed phase having a particle size of 3.0 μm or more to the entire analysis area was calculated.

The evaluation results of Examples 1 to 12 are shown in Table 1, and the evaluation results of Reference Example 1 and Comparative Examples 1 to 10 are shown in Table 2.

As shown in Tables 1 and 2, the molded article obtained from the polyamide-based thermoplastic elastomer compositions of Examples 1 to 12 includes the polyamide-based thermoplastic elastomers of Comparative Examples 1 and 2 and the polyamide composition of Comparative Example 3. It can be seen that the maintenance temperature of the 10 MPa storage elastic coefficient is higher and the oil resistance is higher than that of the molded products obtained from the polyamides of Comparative Examples 4 and 10. It is considered that this is because in the molded products of Examples 1 to 12, a specific sea-island structure was formed by dynamic cross-linking, and the copolymer rubber [III] constituting the dispersed phase was cross-linked. .. Further, in the polyamide-based thermoplastic elastomer composition of Comparative Example 5, pellets could not be prepared and measurement was impossible.

The molded product obtained from the polyamide-based thermoplastic elastomer compositions of Examples 1 to 12 containing the aliphatic polyamide [I] is obtained from the polyamide-based thermoplastic elastomer of Reference Example 1 containing the semi-aromatic polyamide R-4. It can be seen that the maintenance temperature of the 10 MPa storage elastic coefficient is higher and the oil resistance is also higher than that of the molded product. This is because the degree of crystallinity of the aliphatic polyamide [I] constituting the matrix phase is high and the rigidity (storage elastic modulus) at high temperature is increased, so that the copolymer rubber [II] component is swollen by the oil. It is probable that it was suppressed.

Further, the molded product obtained from the polyamide-based thermoplastic elastomer composition of Example 3 has a storage modulus of 10 MPa more than that of the molded product obtained from the polyamide-based thermoplastic elastomer composition of Comparative Example 9 using the unmodified olefin polymer. It can be seen that the maintenance temperature of the rate is high and the oil resistance is also high. Further, the molded product obtained from the polyamide-based thermoplastic elastomer composition of Example 3 is 10 MPa more than the molded product obtained from the polyamide-based thermoplastic elastomer composition of Comparative Example 8 containing no modified olefin polymer [III]. It can be seen that the maintenance temperature of the storage elastic modulus is high and the oil resistance is also high.

Further, it can be seen that by using the aliphatic polyamide [I] having a small MFR value, the particle size of the obtained dispersed phase becomes small and fine dispersion becomes easy. As a result, it can be seen that the oil resistance can be further improved, especially at high temperatures (contrast with Examples 6 to 8).

Further, when the mass ratio ([II] / [I]) of the copolymer rubber [II] and the aliphatic polyamide [I] is 40 or less / 60 or more, that is, the mass ratio of the copolymer rubber [II]. It can be seen that when is less than a certain value, the particle size of the obtained dispersed phase becomes small and fine dispersion becomes easy. As a result, it can be seen that the maintenance temperature of the 10 MPa storage elastic modulus and the oil resistance can be further increased (contrast with Examples 3 to 5).

Further, by setting the content of the cross-linking aid [V] (preferably zinc oxide) so that the mass ratio [V] / [I] is 0.0001 to 0.02, the storage elastic modulus of 10 MPa is increased. It can be seen that the maintenance temperature and oil resistance can be further increased. By setting the content of the cross-linking aid [V] in the above range, the cross-linking rate becomes moderately slow, and after the copolymer rubber [II] is dispersed, dynamic cross-linking proceeds, and the copolymer It is considered that this is because a specific sea-island structure having a good dispersion of rubber [II] is easily formed (comparison between Examples 3, 9 and 10 and Comparative Examples 6 and 7).

Further, it can be seen that by using zinc oxide as the cross-linking aid [V], the maintenance temperature and oil resistance of the 10 MPa storage elastic modulus can be further increased as compared with the case of using zinc carbonate or zinc stearate. It is considered that this is because zinc oxide has a higher rate of activating the cross-linking agent [V] than zinc carbonate or zinc stearate (compared with Examples 3, 11 and 12).

Further, by setting the cumulative cross-sectional area of the dispersed phase having a particle size of 3.0 μm or more to 10% or less with respect to the entire analyzed area, the oil resistance is further enhanced (Examples 1 to 12 and Reference Example 1 and). (Compared with Comparative Examples 1 to 10), by setting the cumulative cross-sectional area of the dispersed phase having a particle size of 3.0 μm or more to 5% or less, and further to 3% or less, the maintenance temperature of the 10 MPa storage elastic modulus can be further increased. Can be understood (contrast with Examples 1 to 12). Furthermore, it can be seen that when the average particle size of the dispersed phase is 1.5 μm or less, the maintenance temperature and oil resistance of the 10 MPa storage elastic modulus are further enhanced (compared with Examples 3 to 5 and compared with Examples 9 to 12). ..

This application claims priority under Japanese Patent Application No. 2016-216083 filed on November 4, 2016. All the contents described in the application specification and drawings are incorporated in the specification of the present application.

According to the present invention, it is possible to provide a polyamide-based thermoplastic elastomer composition which has flexibility at room temperature, maintains elastic modulus even at high temperature, and can impart a molded product having high oil resistance. ..

Claims (16)

A dicarboxylic acid structural unit containing 80 mol% or more of an aliphatic dicarboxylic acid structural unit having 2 to 14 carbon atoms and an aliphatic diamine structural unit having 4 to 12 carbon atoms is a total diamine structural unit. It is an aliphatic polyamide composed of a diamine structural unit containing 80 mol% or more with respect to a diamine structural unit, or an aliphatic polyamide composed of an amidecarboxylic acid structural unit or a lactam structural unit, and has a melting point measured by differential scanning calorific value measurement (DSC). Aliphatic polyamide [I] having a Tm) of 200 to 290 ° C. was added to 10 to 60% by mass.
A non-conjugated polyene having an ethylene structural unit [a], an α-olefin structural unit [b] having 3 to 20 carbon atoms, and one or more carbon-carbon double bonds that can be polymerized by a metallocene-based catalyst in one molecule. Ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] containing the structural unit [c] is contained in an amount of 33 to 86% by mass.
The olefin polymer [III] containing 0.3 to 5.0% by mass of the functional group structural unit was 0.1 to 30% by mass.
The mass ratio [V] / [I] to the aliphatic polyamide [I] is 0.0001 to 0.02, with the phenol resin-based cross-linking agent [IV] being 1 to 10% by mass and the cross-linking aid [V]. Zinc compound and
It is a crosslinked product of a rubber composition containing (however, the total of [I], [II], [III] and [IV] is 100% by mass).
The mass ratio [II] / [I] of the ethylene / α-olefin / non-conjugated polyene copolymer rubber to the aliphatic polyamide [I] is 54/46 to 20/80.
The matrix phase containing the aliphatic polyamide [I], the ethylene / α-olefin / non-conjugated polyene copolymer rubber [II] dispersed and crosslinked in the matrix phase, and the olefin polymer [III] are mixed. Has a dispersed phase, including
The proportion of the dispersed phase having a particle size of 3 μm or more is 10% or less.
Polyamide-based thermoplastic elastomer composition. The aliphatic polyamide [I] is one or more selected from the group consisting of polyamide 6, polyamide 6/6, polyamide 6/10, polyamide 6/12, polyamide 9/2 and polyamide 10/10.
The polyamide-based thermoplastic elastomer composition according to claim 1. The aliphatic polyamide [I] is at least one selected from the group consisting of polyamide 6, polyamide 6/6 and polyamide 6/10.
The polyamide-based thermoplastic elastomer composition according to claim 2. The melt flow rate (MFR) of the aliphatic polyamide [I] at 290 ° C. and 2.16 kg load according to ISO 1133 is 0.1 to 100 g / 10 minutes.
The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 3. The functional group structural unit of the olefin polymer [III] includes a structural unit derived from one or more functional groups selected from the group consisting of a carboxylic acid group, an ester group, an ether group, an aldehyde group and a ketone group.
The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 4. The functional group structural unit of the olefin polymer [III] is a maleic anhydride structural unit.
The polyamide-based thermoplastic elastomer composition according to claim 5. The phenol resin-based cross-linking agent [IV] contains a halogenated phenol resin-based cross-linking agent.
The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 6. The zinc compound is one or more selected from the group consisting of zinc oxide, zinc carbonate, zinc carboxylate and zinc hydroxide.
The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 7. The zinc compound is zinc oxide.
The polyamide-based thermoplastic elastomer composition according to claim 8. The average particle size of the dispersed phase analyzed by the transmission electron microscope image is 0.3 to 5.0 μm.
The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 9. The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 10.
Molded body. The polyamide-based thermoplastic elastomer composition according to any one of claims 1 to 10.
Hollow molded body. The hollow molded body is an automobile-related part.
The hollow molded body according to claim 12. The automobile-related parts are intake / exhaust system parts.
The hollow molded body according to claim 13. The intake / exhaust system parts are an air hose, an air duct, a turbo duct, a turbo hose, an intake manifold, or an exhaust manifold.
The hollow molded body according to claim 14. A dicarboxylic acid structural unit containing 80 mol% or more of an aliphatic dicarboxylic acid structural unit having 2 to 14 carbon atoms and an aliphatic diamine structural unit having 4 to 12 carbon atoms is a total diamine structural unit. An aliphatic polyamide composed of a diamine structural unit containing 80 mol% or more of the amount, or an aliphatic polyamide composed of an amidocarboxylic acid structural unit or a lactam structural unit, and having a melting point measured by differential scanning calorific value measurement (DSC) (DSC). Aliphatic polyamide [I] having a Tm) of 200 to 290 ° C. was added to 10 to 60% by mass.
A non-conjugated polyene having an ethylene structural unit [a], an α-olefin structural unit [b] having 3 to 20 carbon atoms , and one or more carbon-carbon double bonds that can be polymerized by a metallocene-based catalyst in one molecule. Ethylene / α- olefin / non-conjugated polyene copolymer rubber [II] containing the structural unit [c] was added to 33 to 86% by mass.
The olefin polymer [III] containing 0.3 to 5.0% by mass of the functional group structural unit was 0.1 to 30% by mass.
The mass ratio [V] / [I] to the aliphatic polyamide [I] is 0.0001 to 0.02, with the phenol resin-based cross-linking agent [IV] being 1 to 10% by mass and the cross-linking aid [V]. Contains zinc compounds,
The mass ratio [II] / [I] of the ethylene / α-olefin / non-conjugated polyene copolymer rubber to the aliphatic polyamide [I] is 54/46 to 20/80.
A step of preparing a rubber composition containing (however, the total of [I], [II], [III] and [IV] is 100% by mass) and
A step of dynamically cross-linking the rubber composition.
A method for producing a polyamide-based thermoplastic elastomer composition.

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