JPH05295223A - Thermoplastic elastomer composition - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a thermoplastic elastomer composition having excellent heat resistance, which combines the properties of a polyamide and an olefin elastomer. [Structure] (a) Polyamide, (b) General Formula (1) [In the formula, R is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, Ar is an aromatic hydrocarbon group having 6 to 20 carbon atoms having at least one glycidyloxy group, and n is 1
Represents an integer of ~ 4. ] An olefinic elastomer modified with an unsaturated glycidyl compound represented by
(C) A styrene-based thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof is melt-kneaded, and the ratio of the component (a) to the component (b) + (c) is (a) by weight. ) / {(B) + (c)} = 2 / 98-50 /
50, and the ratio of the component (b) and the component (c) is (b) / (c) = 2/98 to 98/2 in weight ratio, The thermoplastic elastomer composition characterized by the above-mentioned.

Description

Detailed Description of the Invention

[0001]

The present invention relates to melt kneading a polyamide, an olefin elastomer modified with a specific unsaturated glycidyl compound, and a styrene thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof. And a thermoplastic elastomer composition. More specifically, it is a heat that combines the properties of polyamide and olefin elastomer, which is suitable for interior and exterior parts of automobiles, industrial material parts such as belts and pipes, electric / communication parts, sports goods, and molded products such as home appliances. It relates to a plastic elastomer composition.

[0002]

2. Description of the Related Art Polyamide is a resin having excellent heat resistance, and polyamide is used as a hard segment,
BACKGROUND ART Polyamide-based thermoplastic elastomers having a soft segment of polyester or polyether are drawing attention as a thermoplastic elastomer composition having excellent heat resistance, which is a feature of polyamide, and moldability of soft segments, and having excellent heat resistance. However, the polyamide-based thermoplastic elastomer has the drawbacks of high specific gravity and high water absorption. On the other hand, the polyolefin-based thermoplastic elastomer has the characteristics of low specific gravity and small water absorption, but it is not suitable for use at high temperatures because of its low softening point. Therefore, by blending a polyamide excellent in heat resistance to the thermoplastic polyolefin-based elastomer,
The heat resistance of the polyolefin-based thermoplastic elastomer is improved, and a lightweight (low specific gravity) and good heat-resistant thermoplastic elastomer composition having excellent water resistance not found in the polyamide-based thermoplastic elastomer can be obtained. There is expected.

However, since the polyolefin-based elastomer has poor compatibility with polyamide, the improvement of the heat resistance of the polyolefin-based thermoplastic elastomer composition containing polyamide is insufficient. Therefore, an object of the present invention is to solve the drawbacks of conventional polyamide-based thermoplastic elastomers and polyolefin-based thermoplastic elastomers, and to provide a lightweight and heat-resistant thermoplastic elastomer composition that combines the properties of polyamide and olefin-based elastomers. To provide.

[0004]

As a result of earnest research in view of the above object, the present inventors have found that a specific amount of a modified olefin-based elastomer modified with a specific glycidyl compound having an acrylamide group and an epoxy group, A specific amount of a modified olefin elastomer modified with a saturated carboxylic acid or a derivative thereof, by blending a specific amount of polyamide and melt-kneading, the polyamide and the modified olefin elastomer are well compatibilized, The present invention has been accomplished by finding that a thermoplastic elastomer composition having excellent heat resistance and having well-balanced properties of an olefin-based elastomer can be obtained.

That is, according to the present invention, (a) polyamide and (b) the following general formula (1)

[0006]

[Chemical 2]

[In the formula, R represents a hydrogen atom or a carbon number of 1 to 6
Of Ar, Ar is an aromatic hydrocarbon group having 6 to 20 carbon atoms and having at least one glycidyloxy group, and n represents an integer of 1 to 4. ] An olefinic elastomer modified with an unsaturated glycidyl compound represented by the formula (c) and (c) a styrene-based thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof are melt-kneaded to obtain the above-mentioned component (a). The ratio of the components (b) + (c) is (a) / {(b) + (c)} = 2/98 by weight ratio.
50/50, and the ratio of the component (b) and the component (c) is
The thermoplastic elastomer composition is (b) / (c) = 2/98 to 98/2 in weight ratio.

Hereinafter, the thermoplastic elastomer composition of the present invention will be described in detail. The (a) polyamide of the thermoplastic elastomer composition component of the present invention is a thermoplastic resin having an amide bond, such as hexamethylene diamine,
Decamethylenediamine, dodecamethylenediamine, 2,
Of 2,4- or 2,4,4-trimethylhexamethylenediamine, 1,3- or 1,4-bis (aminomethyl) cyclohexane, bis (p-aminocyclohexylmethane), m- or p-xylylenediamine From aliphatic, cycloaliphatic or aromatic diamines and aliphatic, cycloaliphatic or aromatic dicarboxylic acids such as adipic acid, suberic acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid Polyamides produced, polyamides produced from aminocarboxylic acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, ε-caprolactam, ω
-Polyamides produced from lactams such as dodecalactam, copolyamides composed of these components, mixtures of these polyamides and the like.

Specific examples of the polyamide include nylon 6, nylon 66, nylon 610, nylon 9, nylon 6/66, nylon 66/610, nylon 6 /
11, nylon 6/12, nylon 12, nylon 4
6, amorphous nylon and the like. Among these,
Nylon 6 and nylon 66, which have particularly good rigidity and heat resistance, are preferable. In the present invention, the molecular weight of the polyamide is not particularly limited, but a polyamide having a relative viscosity η _r measured in 98% sulfuric acid based on JIS K6810 of 0.5 or more, among them,
Those of 2.0 or more are preferably used.

In the modified olefin elastomer (b) modified with an unsaturated glycidyl compound which is a component of the thermoplastic elastomer composition used in the present invention, the olefin elastomer used as the modifying raw material is ethylene, propylene, butene- 1, hexene-1, 4-methyl-pentene-1, etc. means a copolymer rubber with one or more α-olefins other than ethylene, and component (b) is an unmodified olefin elastomer. It may be contained up to about 80% by weight. Specific examples of the copolymer rubber with one or more α-olefins used in the present invention include ethylene-propylene copolymer rubber (EP
R), ethylene-butene copolymer rubber (EBR), ethylene-propylene-diene copolymer rubber (EPDM) and the like. Examples of the diene component in the ethylene-propylene-diene copolymer rubber (EPDM) include non-conjugated dienes such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene and methylenenorbornene,
Alternatively, a conjugated diene such as butadiene or isoprene may be used. The ethylene content in the olefin elastomer is preferably 5 to 95% by weight, more preferably 10 to 90.
% By weight. If the ethylene content is less than 5% by weight or more than 95% by weight, it becomes difficult to exhibit properties as an elastomer. The crystallinity of the olefin elastomer is preferably 40% by weight or less.

In the ethylene-propylene copolymer rubber (EPR) used in the present invention, the content of repeating units derived from ethylene is 50 to 80 mol%, and the content of repeating units derived from propylene is 20 to 20%. It is preferably 50 mol%. More preferably, the content of ethylene-based repeating units is 60 to 70 mol%, and the content of propyne-based repeating units is 30 to 40 mol%.
In addition, the EPR melt flow rate (MFR, 230
C., 2.16 kg load) is preferably in the range of 0.01 to 50 g / 10 minutes, more preferably 0.5 to 30 g / 10 minutes.

The ethylene-butene copolymer rubber (EBR) used in the present invention has a content of repeating units derived from ethylene of 50 to 90 mol% and a content of repeating units derived from butene of 10 to 10. It is preferably 50 mol%. More preferably, the content of ethylene-based repeating units is 60 to 80 mol% and the content of butene-based repeating units is 20 to 40 mol%. Also, EB
The melt flow rate of R (MFR, 230 ° C., 2.16 kg load) is preferably in the range of 0.01 to 50 g / 10 minutes, more preferably 0.5 to 30 g / 10 minutes.

The ethylene used in the present invention
The propylene-diene copolymer (EPDM) has a repeating unit content of 40 to 70 mol% derived from ethylene, a repeating unit content of 30 to 60 mol% derived from propylene, and a diene-derived copolymer. The content of the repeating unit is preferably 1 to 10 mol%. More preferably, the content of ethylene-based repeating units is 50 to 60 mol%, the content of propylene-based repeating units is 40 to 50 mol%, and the content of diene-based repeating units is 3 to 6 mol%. .. In addition, EPDM melt flow rate (MFR, 230 ℃, 2.16kg load)
Is preferably in the range of 0.01 to 50 g / 10 minutes,
It is more preferably 0.1 to 30 g / 10 minutes.

The ethylene-propylene copolymer (EPR), the ethylene-butene copolymer rubber (EBR), and the ethylene-propylene-diene copolymer (EPDM) used in the present invention are within the range that does not impair the characteristics. Thus, other repeating units such as repeating units derived from other α-olefins such as 4-methylpentene-1 may be contained up to a proportion of 10 mol% or less.

In the present invention, it is also possible to use an olefin elastomer composition in which a polyolefin, preferably a crystalline polyolefin, is mixed with the above-mentioned olefin elastomer. As the crystalline polyolefin,
Ethylene, propylene, butene-1, hexene-1, 4
-Homopolymers of α-olefins such as methyl-pentene-1, non-elastomeric copolymers of ethylene and propylene or other α-olefins, or two or more non-elastomeric copolymers of these α-olefins A combination, a homopolymer of these homopolymers, a mixture of a homopolymer and a copolymer, and the like can be used. Of these polyolefins, polyethylene and polypropylene are preferred. Specific examples of polyethylene include low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and high density polyethylene (HDPE). When the polyolefin is mixed, the mixing amount is 80% by weight or less, preferably 50% by weight or less, based on the total amount of the olefin elastomer and the polyolefin (100% by weight). When the amount of the polyolefin mixed exceeds 80% by weight, the properties as an elastomer are lost.

The unsaturated glycidyl compound used for modifying the olefinic elastomer in the present invention means the following general formula (1) having an acrylamide group and an epoxy group in the molecule.

[0017]

[Chemical 3]

[Each symbol in the formula has the same meaning as described above. ] It is a glycidyl compound represented by these. Among the glycidyl compounds represented by the above general formula, the glycidyl compound represented by the following general formula (2) is particularly preferable.

[0019]

[Chemical 4]

[In the formula, R represents the same meaning as described above. ]
Such a glycidyl compound is disclosed, for example, in JP-A-60-13058.
It can be produced by the method shown in No. 0. These glycidyl compounds are usually used alone, but two or more kinds can be used in combination.

Preferred modified olefin elastomers in the present invention are the above-mentioned starting olefin elastomers, especially EPR, EBR or EPDM, which are glycidyl compounds represented by the general formula (1), particularly glycidyl compounds represented by the general formula (2). It is modified with a compound. The content of the unsaturated glycidyl compound as a modifier of the modified olefin elastomer varies depending on the kind of the raw material olefin elastomer and cannot be generally stated, but it is generally about 0.01 to 30% by weight, preferably 0.1.
10 to 10% by weight. When the content of the unsaturated glycidyl compound is less than 0.01% by weight, modification of the olefinic elastomer is insufficient, and when it exceeds 30% by weight, gelation occurs at the time of blending with the polyamide, resulting in poor moldability.

Such a preferable modified olefin elastomer can be obtained by utilizing a known modification method such as a solution method or a melt kneading method. In addition, a desired product may be appropriately selected from commercially available products and used. As a specific example of the modification method, a modification example (graft polymerization) of the olefinic elastomer with the glycidyl compound is shown below. That is, in the melt-kneading method, an olefin elastomer, the glycidyl compound described above, and a catalyst as required are used, and these components are charged into an extruder, a twin-screw kneader, or the like and heated to a temperature of about 180 to 300 ° C. While being melted, the mixture is kneaded for about 0.1 to 20 minutes to obtain a modified olefin elastomer. In the case of the solution method, the above-mentioned starting materials are dissolved in an organic solvent such as xylene, and modification is carried out while stirring at a temperature of about 90 to 200 ° C for 0.1 to 100 hours.
In any of the modification methods, it is possible to use a normal radical polymerization catalyst as a catalyst, for example, benzoyl peroxide, lauroyl peroxide, ditertiary butyl peroxide,
Acetyl peroxide, tertiary butyl peroxybenzoic acid, dicumyl peroxide, peroxybenzoic acid, peroxyacetic acid, tertiary butyl peroxypivalate, 2,
Peroxides such as 5-dimethyl-2,5-ditert-butylperoxyhexyne and azo compounds such as α, α-azobisisobutyronitrile are used. The amount of the catalyst added is about 0.1 to 10 parts by weight with respect to 100 parts by weight of the glycidyl compound for modification. It is also possible to add a phenolic antioxidant during the above graft reaction.

In the modified styrene type thermoplastic elastomer (c) modified with an unsaturated carboxylic acid or its derivative of the thermoplastic elastomer composition component used in the present invention, the styrene type thermoplastic elastomer used as a modifying raw material is It is a copolymer of a styrene-based monomer and another monomer such as a mono-olefin or a di-olefin which is copolymerizable with the styrene-based monomer, a copolymer such as a block or a graft, and a hydrogenated product of these copolymers.

Here, as the styrene-based monomer, styrene, α-chlorostyrene, 2,4-dichlorostyrene, p-methoxystyrene, p-methylstyrene, p-
Phenylstyrene, p-divinylbenzene, p- (chloromethoxy) -styrene, α-methylstyrene, o-methyl-α-methylstyrene, m-methyl-α-methylstyrene, p-methyl-α-methylstyrene, p -Methoxy-α-methylstyrene and the like can be mentioned. Of these, styrene is preferably used. Examples of the diolefin include non-conjugated dienes such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene and methylnorbornene, or conjugated dienes such as butadiene and isoprene. Of these, butadiene and isoprene are preferred. Further, as the mono-olefin, in addition to ethylene, propylene, butene-1, hexene-1,
Examples thereof include α-olefins having 3 or more carbon atoms such as 3-methylbutene-1, 4-methyl-pentene-1, heptene-1, octene-1, and decene-1, and of these, ethylene and propylene are preferable.

The styrene-based thermoplastic elastomer used as a raw material elastomer for the modified styrene-based thermoplastic elastomer in the component (c) of the present invention is prepared by using the above-mentioned suitable monomer by a known suitable method such as anionic polymerization or radical polymerization. It can be obtained by copolymerization. Specific examples of preferable raw material elastomers include styrene-butadiene-styrene block copolymer (SBS) and its hydrogenated product styrene-ethylene-butylene-styrene block copolymer (SEBS).
Styrene-butadiene copolymer (SB) and hydrogenated product thereof, styrene-ethylene-butylene block copolymer (SEB), styrene-isoprene copolymer (SI) and hydrogenated product thereof, styrene-ethylene-propylene block copolymer Examples thereof include a polymer (SEP), a styrene-isoprene-styrene block copolymer (SIS), and a hydrogenated product thereof, a styrene-ethylene-propylene-styrene block copolymer (SEPS).
BS and SEPS are particularly preferred. The raw material elastomer preferably has a styrene-based monomer content of 5 to 80% by weight, particularly preferably 10 to 70% by weight. As such a preferable raw material styrene-based thermoplastic elastomer, a desired one may be appropriately selected from commercial products and used.

Examples of the unsaturated carboxylic acid or its derivative used for modifying the styrene-based thermoplastic elastomer in the present invention include acrylic acid, methacrylic acid, maleic acid, endo-bicyclo [2.2.1] -5-. Hepten-
2,3-dicarboxylic acid (Endic acid), fumaric acid,
Examples thereof include unsaturated mono- or dicarboxylic acids such as tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid and isocrotonic acid, or derivatives thereof such as acids, halides, amides, imides, anhydrides and esters. Specific examples of the derivative include maleenyl chloride, maleimide, maleic anhydride, endic acid anhydride, methyl acrylate, methyl methacrylate, citraconic anhydride, monomethyl maleate, dimethyl maleate and the like. Among these, unsaturated dicarboxylic acids or their derivatives are preferable, and maleic acid and endic acid, or their anhydrides are particularly preferable. These modifiers are usually used alone, but two or more kinds may be used in combination.

The modified styrenic thermoplastic elastomer preferred in the present invention is the above-mentioned raw material styrenic thermoplastic elastomer, especially SEBS or SEPS, the unsaturated dicarboxylic acid or its derivative, particularly maleic acid and endic acid, or their derivatives. It is modified with an anhydride. In addition, a desired product may be appropriately selected from commercially available products and used. The content of the unsaturated carboxylic acid or its derivative as a modifier of the modified styrene-based thermoplastic elastomer varies depending on the type of the raw material styrene-based thermoplastic elastomer and cannot be stated unconditionally, but generally 0.01 to 15% by weight, It is preferably 0.1 to 10% by weight. If the content of the unsaturated carboxylic acid or its derivative is less than 0.01% by weight, the modification of the styrene-based thermoplastic elastomer is insufficient, and if it exceeds 10% by weight, gelation occurs when blending with the polyamide, resulting in poor moldability. Become. Such a preferable modified styrene-based thermoplastic elastomer is obtained by copolymerizing the above-mentioned raw material styrene-based thermoplastic elastomer and an unsaturated carboxylic acid or a derivative thereof using a known modification method such as a solution method or a melt-kneading method. Obtainable. In this modification, as a catalyst, for example, a catalyst for radical polymerization can be selected and used from those mentioned in the modification of the olefin elastomer.

The mixing ratio of each component is (a) polyamide, (b) modified olefin elastomer modified with unsaturated glycidyl compound, and (c) modified styrene system modified with unsaturated carboxylic acid or its derivative. Thermoplastic elastomer and (a) / {(b) + (c)} in weight ratio
= 2 / 98-50 / 50, preferably 5 / 95-50 /
50. If the weight ratio is less than 2/98, the amount of polyamide is too small, and the effect of improving the heat resistance of the elastomer composition by using the polyamide cannot be recognized. If it exceeds 50/50, the properties as an elastomer are lost. Also,
The ratio of the component (b) and the component (c) is (b) / weight ratio.
(C) = 2/98 to 98/2, preferably 5/95 to 9
It is 5/5. When the weight ratio is less than 2/98 or exceeds 98/2, 2 of the component (b) and the component (c) are contained.
Since the proportion of one of the two types of elastomer components is reduced and sufficient thickening of the rubber phase does not occur, the effect of improving the physical properties of the elastomer composition due to the combined use of both is not recognized.

In the present invention, in addition to the above-mentioned substances, other substances such as fillers and reinforcing materials such as glass fibers, heat stabilizers and light stabilizers are further used for the purpose of strengthening and modifying the thermoplastic elastomer composition. , Flame retardants, plasticizers, antistatic agents, foaming agents, nucleating agents, and the like can be added. The thermoplastic elastomer composition of the present invention can be obtained by melt-kneading the above components using a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneading roll, a kneader such as a Brabender, or the like. Kneading temperature is polyamide,
It depends on the type of the modified olefin-based elastomer and the modified styrene-based thermoplastic elastomer and cannot be said to be unconditional, but it is appropriately 220 to 300 ° C., and preferably 240 to 300 ° C. Kneading temperature is 22
If the temperature is below 0 ° C, the components will not be sufficiently kneaded, and
At temperatures above 00 ° C, the thermoplastic elastomer composition may deteriorate.

In the present invention, the kneading order of each component is not particularly limited, and the components (a), (b) and (c) may be kneaded together, or the components (a) and (b) may be kneaded. After that, the component (c) may be kneaded. Furthermore, when a modified olefin elastomer containing an unmodified olefin elastomer is used as the component (b), the unmodified olefin elastomer and the modified olefin elastomer can be kneaded as independent components.
For example, unmodified olefin elastomer and component (a)
After kneading and, the modified olefin elastomer and the component (c) may be kneaded, or other kneading order may be adopted.

[0031]

The thermoplastic elastomer composition of the present invention comprises an olefin-based elastomer modified with a specific unsaturated glycidyl compound having an acrylamide group and an epoxy group, and a styrene-based thermoplastic resin modified with an unsaturated carboxylic acid or its derivative. A thermoplastic elastomer, which is prepared by mixing and kneading a polyamide, and is a lightweight thermoplastic elastomer composition having excellent heat resistance that compatibilizes the polyamide and the modified olefin-based elastomer well, and has the properties of both in a well-balanced manner. is there. Although the detailed reason why the thermoplastic elastomer composition of the present invention exerts such an effect is not always clear, the unsaturated glycidyl component in the modified olefin-based elastomer and the unsaturated carboxylic acid in the modified styrene-based thermoplastic elastomer are Alternatively, due to the interaction (reaction) with the derivative component thereof, a cross-linking reaction occurs between the two types of modified elastomers to increase the viscosity, and further, through the reaction of the polyamide and the unsaturated glycidyl component, the polyamide and the modified olefin system It is considered that this is due to compatibility with the elastomer.

[0032]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. In each of the examples and comparative examples, the following materials were used as raw materials and additives. Polyamide (1) Nylon 6 Ny6: [A1030BRL manufactured by Unitika Ltd.] (2) Nylon 66 Ny66: [Toray Industries, Inc. Amilan 3001N] (3) Amorphous nylon AmNy: [XE3038 manufactured by Ems Co., Ltd.] Olefin-based elastomer (1) Ethylene-propylene copolymer rubber EPR: [PO180 manufactured by Mitsui Petrochemical Co., Ltd., melt flow rate (MFR, 230 ° C., 2.16 kg load) 6.0 g / 1
0 minutes] (2) Ethylene-butene copolymer rubber EBR: [Japan Synthetic Rubber Co., Ltd. EBM2041P, melt flow rate (MFR, 230 ° C, 2.16 kg load) 5.0 g
/ 10 min] Modification monomer AXE: glycidyl compound represented by the following chemical formula [Kanefuchi Chemical Industry Co., Ltd.]

[0033]

[Chemical 5]

Polyamide-based thermoplastic elastomer PAEl: [manufactured by Daicel Huls KK, Daiamide E62] Polyolefin-based thermoplastic elastomer POEl: [Sumitomo Chemical Co., Ltd. TPE1500, melt flow rate (MFR, 230 ° C., 2.16 kg load) 0.1 g / 1
0 minutes] Modified styrenic thermoplastic elastomer MAH-SEBS: [MAH (maleic anhydride) modified S
EBS, manufactured by Asahi Kasei Corporation, Tuftec M1913, styrene content 30% by weight, MAH graft ratio 1% by weight]

Modified olefin elastomer (1) AXE modified ethylene-propylene copolymer rubber Ethylene-propylene copolymer rubber [melt flow rate (MFR, 230 ° C., 2.16 kg load) 6.0 g / 10 minutes]
80 parts by weight and polyethylene (HDPE) [melt flow rate (MFR, 190 ° C, 2.16 kg load) 5.0 g / 1
0 minutes] 20 parts by weight, AXE 3 parts by weight and organic peroxide [Perhexin 25B (manufactured by NOF Corporation)] 0.03
After dry blending parts by weight, this was melt-kneaded using a uniaxial extruder having a diameter of 65 mm at 200 ° C and 60 rpm to obtain a melt flow rate (MFR, 230 ° C, 2.16 kg).
A load) 3.3 g / 10 min of a modified olefin elastomer (AXE-EPR) was obtained. The AXE graft ratio of this modified olefin elastomer was 2.3% by weight. The graft ratio was calculated by the following method. The modified olefin elastomer is dissolved in boiling xylene, the insoluble matter is removed, and then the dissolved component is precipitated with methanol, and this is pressed to a thickness of about 50 μm, the IR spectrum is measured, and the C = O bond of AXE is measured. Expansion peak (16
It was calculated from the ratio of 48 cm ⁻¹ ) to one of the isotactic PP-specific peaks (840 cm ⁻¹ ).

(2) AXE-modified ethylene-butene copolymer rubber Ethylene-butene copolymer rubber [melt flow rate (MFR, 230 ° C., 2.16 kg load) 7.0 g / 10 min] 1
00 parts by weight, 3 parts by weight of AXE and 0.1 part by weight of an organic peroxide [Perhexin 25B (manufactured by NOF CORPORATION)] were dry blended, and then this was blended using a uniaxial extruder having a diameter of 65 mm at 200 ° C. and 60 rpm. Melt and knead under the conditions,
Melt flow rate (MFR, 230 ℃, 2.16kg load)
3.2 g / 10 minutes modified olefin elastomer (AX
E-EBR) was obtained. The modified olefin elastomer had an AXE graft ratio of 2.1% by weight. The graft ratio was determined in the same manner as in the case of AX-EPR.

Examples 1 to 12 and Comparative Examples 1 to 9 Polyamide (Ny6, Ny66 or AmNy), olefin elastomer (EPR or EBR) and modified olefin elastomer (AXE-EPR or A).
XE-EBR) and modified styrene thermoplastic elastomer (MAH-SEBS) were dry-blended with a Henschel mixer at a ratio shown in Table 1, and then the diameter was 45 mm.
With a twin-screw extruder (L / D = 30) at 280 ° C., 20
Melt kneading at 0 rpm gave pellets of the thermoplastic elastomer composition. The thermoplastic elastomer composition thus obtained was injection-molded, and the specific gravity, Vicat softening point, surface hardness, permanent elongation, and elongation at break of the molded product were measured. The results are shown in Table 1.

[0038]

[Table 1]

[0039]

[Table 2]

[0040]

[Table 3]

The methods for measuring the physical properties shown in Table 1 above are as follows. (1) Specific gravity: Measured according to JIS K6911. (2) Vicat softening point: measured according to ASTM D1525. (3) Surface hardness (23 ° C.): Shore D hardness was measured according to ASTM D2240. (4) Permanent elongation (23 ℃): 100% based on JISK6301
Evaluation by extension. (5) Elongation at break (23 ° C.): Measured according to JIS K6301.

As is clear from Table 1, the softening points of the compositions comprising polyamide and the unmodified olefin elastomer (Comparative Examples 6 and 8) were as follows. It is at the same level as the softening point of Example 5), and no improvement in heat resistance due to the blending of polyamide (Comparative Examples 1, 2 and 3) is observed. Further, as the elongation at break is low and the permanent elongation cannot be measured, the properties as an elastomer are deteriorated, and it can be seen that the compatibility between the polyamide and the olefin elastomer is poor. Furthermore, a composition comprising a polyamide and a modified olefin elastomer (Comparative Examples 7 and 9)
Although the properties as an elastomer are improved, the softening point is still low, and it can be seen that the compatibility between the polyamide and the modified olefin elastomer is poor.

On the other hand, a thermoplastic elastomer composition of the present invention containing an olefin-based elastomer modified with an unsaturated glycidyl compound and a styrene-based thermoplastic elastomer modified with an unsaturated carboxylic acid or its derivative is Commercially available polyolefin-based thermoplastic elastomer containing no polyamide (Comparative Example 5), compositions comprising polyamide and unmodified olefin-based elastomer (Comparative Examples 6 and 8), compositions comprising polyamide and modified olefin-based elastomer ( Compared to Comparative Examples 7 and 9),
All the physical properties such as softening point, surface hardness, permanent elongation, and elongation at break are well balanced, and the improvement of the softening point is particularly remarkable. Further, the specific gravity is lower than that of the thermoplastic polyamide-based elastomer (Comparative Example 4), and the permanent elongation is good.

[0044]

As described above, the thermoplastic elastomer composition of the present invention comprises an olefin elastomer modified with a specific unsaturated glycidyl compound having an acrylamide group and an epoxy group, and an unsaturated carboxylic acid or its A styrene-based thermoplastic elastomer modified with a derivative is blended with a polyamide and melt-kneaded. The properties of the polyamide and the olefin-based elastomer are well balanced, the heat resistance is excellent, and the specific gravity is low. Such a thermoplastic elastomer composition of the present invention, as various engineering elastomers, especially automotive interior and exterior parts, industrial material parts such as belts and pipes,
It is suitable as an elastomer composition for electric / communication parts, sports equipment, home electric appliances and the like.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Fujita 1-3-1 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Tonen Research Institute

Claims (1)

[Claims] 1. A polyamide and (b) the following general formula (1): [In the formula, R is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, Ar is an aromatic hydrocarbon group having 6 to 20 carbon atoms having at least one glycidyloxy group, and n is 1
Represents an integer of ~ 4. ] An olefinic elastomer modified with an unsaturated glycidyl compound represented by
(C) A styrene-based thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof is melt-kneaded, and the ratio of the component (a) to the component (b) + (c) is (a) by weight. ) / {(B) + (c)} = 2 / 98-50 /
50, and the ratio of the component (b) and the component (c) is (b) / (c) = 2/98 to 98/2 in weight ratio, The thermoplastic elastomer composition characterized by the above-mentioned.