JPH085999B2 - Thermoplastic elastomer composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a thermoplastic elastomer composition, and more particularly to oil resistance, mechanical strength and heat resistance composed of a partially crosslinked modified polyolefin elastomer and polyamide. The present invention relates to a thermoplastic elastomer composition having excellent aging properties.

(Prior art and its problems) Thermoplastic elastomers are energy-saving and resource-saving type elastomers, especially automobile parts (bellows, tubes, interior sheets, mudguards, etc.) and industrial machine parts (pressure hoses) as an alternative to vulcanized rubber. , Gaskets, diaphragms), electronic / electromechanical parts, building materials, etc.

As a thermoplastic elastomer, a composition of a crystalline thermoplastic polyolefin resin and a vulcanized ethylene-propylene-polyene copolymer rubber is disclosed in, for example, JP-B-58-46.
No. 138 and Japanese Patent Publication No. 55-18448.
This composition has a drawback that the balance between rubber elasticity and mechanical strength is poor.

Further, a thermoplastic elastomer composition comprising a blend of cross-linked ethylene / propylene / polyene copolymer rubber, acrylonitrile / butadiene copolymer rubber, polypropylene resin and nylon resin is disclosed in US Pat. No. 4,338,413.
No. Although this composition has various properties such as oil resistance, it has a fatal defect of poor heat aging resistance and weather resistance.

A composition comprising a polyolefin resin, an α, β unsaturated carboxylic acid modified product of an ethylene / α-olefin copolymer mixture, and a polyamide is known from JP-A-57-8246. This composition has excellent mechanical strength, but lacks flexibility, which is one of the important properties as a thermoplastic elastomer.

Thus, as far as the inventors of the present invention know, oil resistance,
A thermoplastic elastomer composition excellent in mechanical strength and heat aging resistance has not been known yet.

(Means for Solving Problems) According to the present invention, (a) peroxide cross-linking olefin-based copolymer rubber 95
To 60 parts by weight, (b) 5 to 40 parts by weight of olefinic plastic, (total amount of components (a) and (b) is 100 parts by weight) (c) unsaturated carboxylic acid or its derivative, unsaturated epoxy Obtained by dynamically heat treating a blend containing 0.01 to 10 parts by weight of at least one monomer selected from the group consisting of monomers and unsaturated hydroxy monomers in the presence of organic peroxide. Thermoplastic resin, characterized in that the partially crosslinked graft-modified polyolefin elastomer (A) and the polyamide (B) are blended in a weight ratio of A: B = 60: 40 to 90:10. An elastomer composition is provided.

In the present invention, the blended product further comprises (d) 100 parts by weight or less of a peroxide-non-crosslinked rubber-like substance, and / or (1) based on 100 parts by weight of the total of the components (a) and (b). e) 200 parts by weight or less of a mineral oil-based softening agent may be contained.

(Operation) In the thermoplastic elastomer composition of the present invention, the modified polyolefin-based elastomer of the component (A) is a partially cross-linked olefin-based copolymer rubber and an olefin-based plastic, preferably a peroxide-decomposable olefin-based plastic. Since it is composed of, it maintains excellent fluidity, heat resistance and heat aging resistance, and imparts rubber elasticity.

The polyamide as the component (B) imparts oil resistance and fluidity at high temperature, and thus the elastomer composition retains predetermined oil resistance and moldability.

The thermoplastic elastomer composition of the present invention comprises the component (A),
The advantage of the component (B) is fully exerted in that the component (A) is easily unsaturated with the component (B) by a physical bond or a chemical bond. If it is uniformly modified with at least one monomer selected from the group consisting of saturated hydroxy monomers and the component (A) is unmodified, or is compatible with the components (A) and (B). This is because the strengthening of the blended interface is significantly achieved as compared with the case where the third component having a segment to be added is added.

Thus, according to the present invention, by the action of each of the above components,
Provided is a thermoplastic elastomer composition having excellent oil resistance, mechanical strength, and heat aging resistance.

(Preferred Embodiment of the Invention) (a) Peroxide Crosslinking Olefin Copolymer Rubber The peroxide crosslinking olefin copolymer rubber used in the present invention is, for example, ethylene-propylene copolymer rubber or ethylene-propylene non-conjugated rubber. Diene rubber,
An ethylene-butadiene copolymer rubber, which is an amorphous elastic copolymer containing olefin as a main component, is mixed with an organic peroxide and is kneaded under heating to crosslink to lower the fluidity or A rubber that does not flow.
Incidentally, the non-conjugated diene, dicyclopentadiene, 1,4-
Hexadiene, dicyclooctadiene, methylene norbornene, ethylidene norbornene and the like are referred to.

In the present invention, among these copolymer rubbers, ethylene-propylene copolymer rubber and ethylene-propylene-non-conjugated diene rubber are preferably used, and the molar ratio of ethylene units and propylene units (ethylene / propylene) is
Those having a ratio of 50/50 to 90/10, particularly those having a ratio of 55/45 to 85/15 are preferably used. Among them, ethylene-propylene-non-conjugated diene copolymer rubber, particularly ethylene-propylene-5-ethylidene The 2-norbornene copolymer rubber and the ethylene-propylene-5-ethylidene-2-norbornene-dicyclopentadiene quaternary copolymer provide a thermoplastic elastomer having excellent heat resistance, tensile strength and impact resilience. preferable.

Mooney viscosity of this copolymer rubber ML _{1 + 4} (100 ℃)
10 to 250, particularly 40 to 150 are preferably used, and when the Mooney viscosity is within this range, a composition having excellent tensile properties and fluidity can be obtained.

Further, the iodine value (unsaturation degree) of the copolymer rubber is preferably 25 or less, and in this range, a thermoplastic elastomer having a good balance of fluidity and rubber characteristics can be obtained.

(B) Olefin-based Plastic The olefin-based plastic in the present invention comprises a crystalline high molecular weight solid product obtained from polymerization of one or more monoolefins by either a high-pressure method or a low-pressure method. Examples of such resins include, for example, isotactic and syndiotactic monoolefin homo- or copolymer resins, of which typical ones are commercially available.

Examples of suitable raw material olefins include, for example, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, 5-methyl-1-
Hexene, 1-octene, 1-decene and a mixture of two or more of these can be mentioned. Regarding the polymerization mode, a random type or a block type can be adopted as long as a resinous material can be obtained.

Among them, preferred olefin plastics are peroxide decomposition type olefin plastics and polyethylene.

The peroxide-decomposable olefin-based plastic in the present invention refers to an olefin-based plastic that is mixed with a peroxide and thermally decomposed by kneading under heating to reduce the molecular weight and increase the fluidity of the resin. For example, isotactic Polypropylene or a copolymer of propylene and a small amount of other α-olefin, for example, propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-4-methyl-1. -Pentene copolymer etc. can be mentioned.
The melt index (ASTM-D-1238-65T, 230 ° C) of the mixed olefinic plastic is 0.1 to 50,
The range of 5 to 20 is particularly preferable. In the present invention, the olefin plastic has a role of improving the fluidity of the composition and improving the heat resistance.

(C) Unsaturated carboxylic acid or its derivative, unsaturated epoxy monomer and unsaturated hydroxy monomer In the present invention, as the unsaturated carboxylic acid or its derivative used as one of the components (c), Include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, α, β unsaturated carboxylic acids such as tetrahydrophthalic acid, bicyclo [2,2,1] hept-
Unsaturated carboxylic acids such as 2-ene-5,6-dicarboxylic acid,
Anhydrides of α, β unsaturated carboxylic acids such as maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo [2,2,1] hept-2-ene-5,6
An anhydride of an unsaturated carboxylic acid such as a dicarboxylic acid anhydride,
Methyl acrylate, methyl methacrylate, dimethyl maleate, monomethyl maleate, diethyl fumarate,
Examples thereof include esters of unsaturated carboxylic acids such as dimethyl itaconate, diethyl citraconic acid, dimethyl tetrahydrophthalic anhydride, and dimethyl bicyclo [2,2,1] hept-2-ene-5,6dicarboxylate. Among these, maleic acid, bicyclo [2,2,1] hept-2-ene-5,6-dicarboxylic acid or anhydrides thereof are preferred.

In addition, as the unsaturated epoxy monomer which is another one of the component (c) in the present invention, for example, glycidyl ester of unsaturated monocarboxylic acid such as glycidyl acrylate, glycidyl methacrylate and glycidyl p-styrylcarboxylate; Maleic acid, itaconic acid, citraconic acid, butenetricarboxylic acid, endo-cis-bicyclo [2,2,1] hept-5-ene-2,3-dicarboxylic acid, endo-cis-bicyclo [2,2,1] Hept-5-ene-2-
Monoglycidyl ester or polyglycidyl ester of unsaturated polycarboxylic acid such as methyl-2,3-dicarboxylic acid; allyl glycidyl ether, 2-methyl allyl glycidyl ether, o-allyl phenol glycidyl ether, m-allyl Phenol glycidyl ether, p-allylphenol glycidyl ether, isopropenylphenol glycidyl ether, o-vinylphenol glycidyl ether, m-
Unsaturated glycidyl ethers such as glycidyl ether of vinylphenol and glycidyl ether of p-vinylphenol; 2- (o-vinylphenyl) ethylene oxide, 2- (p-vinylphenyl) ethylene oxide, 2
-(O-vinylphenyl) propylene oxide, 2-
(P-Vinylphenyl) propylene oxide, 2- (o
-(Allylphenyl) ethylene oxide, 2- (p-allylphenyl) ethylene oxide, 2- (o-allylphenyl) propylene oxide, 2- (p-allylphenyl) propylene oxide, p-glycidylstyrene, 3,4 -Epoxy-1-butene, 3,4-epoxy-3-
Methyl-1-butene, 3,4-epoxy-1-pentene,
3,4-Epoxy-3-methyl-1-pentene, 5,6-epoxy-1-hexene, vinylcyclohexene monoxide, allyl-2,3-epoxycyclopentyl ether and the like are preferable.

Further, the unsaturated hydroxy monomer which is another one of the component (c) of the present invention is a monomer having at least one ethylenically unsaturated bond and at least one hydroxyl group, for example, hydroxyethyl acrylate, hydroxypropyl Acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, etc., and particularly, hydroxyethyl (meth)
Acrylate and hydroxypropyl (meth) acrylate are preferred.

These components (c) can be used alone or in combination, and act as a graft modifier during the dynamic heat treatment described below, and strengthen the blend interface between the polyamide and the graft modified polyolefin elastomer. And improves the oil resistance, strength and the like of the molded article made of the thermoplastic elastomer composition.

The graft-modified polyolefin-based elastomer according to the present invention may further contain (d) a peroxide-non-crosslinked rubber-like substance and / or (e) a mineral oil-based softening agent.

(D) Peroxide non-crosslinked rubber-like substance The peroxide non-crosslinked rubber-like substance of the component (d) is, for example, polyisobutylene, butyl rubber (IIR), propylene-ethylene copolymer rubber having 70% by mole or more of propylene, attack It refers to a hydrocarbon-based rubber-like substance such as tic polypropylene which does not crosslink even when mixed with a peroxide and kneaded under heating and does not decrease in fluidity. Of these, polyisobutylene and butyl rubber (IIR) are most preferred for performance and handling.

Such components improve the fluidity of the elastomer composition, and those having a Mooney viscosity of 60 or less are particularly suitable.

Component (d) also improves the permanent set of the thermoplastic elastomer composition.

(E) Mineral oil-based softening agent The mineral oil-based softening agent as the component (e) is a carbon compounded as a filler, which weakens the intermolecular action force of the rubber during normal rubber roll processing to facilitate the processing. black,
A high-boiling petroleum fraction used to increase the flexibility and elasticity by helping to disperse white carbon or reduce the hardness of the vulcanized rubber, and to be used in paraffinic, naphthenic, aromatic, etc. They are distinguished.

Graft-Modified Polyolefin Elastomer (A) The partially cross-linked graft-modified polyolefin elastomer (A) used as the base component of the thermoplastic elastomer composition of the present invention is (a) a peroxide-crosslinking olefin copolymer rubber.
To 60 parts by weight, (b) 5 to 40 parts by weight of olefinic plastic (where (a) + (b) is selected to be 100 parts by weight), and (c) unsaturated carboxylic acid or its 0.01 to 10 parts by weight, particularly 0.1 to 5 parts by weight, of at least one monomer selected from the group consisting of a derivative, an unsaturated epoxy monomer and an unsaturated hydroxy monomer are blended together to form an organic compound. It is obtained by dynamic heat treatment in the presence of peroxide to partially crosslink.

Further, when blending the above respective components, it is preferable to add the above-mentioned component (d) and / or component (e), but the peroxide non-crosslinking rubber-like substance of the component (d) is
The amount is preferably 100 parts by weight or less, preferably 5 to 100 parts by weight, particularly preferably 5 to 50 parts by weight, and the component (e), a mineral oil-based softener, is 200 parts by weight or less, preferably It is preferably used in an amount of 3 to 100 parts by weight, particularly preferably 5 to 80 parts by weight.

By blending the component (a) within the above range, a composition having excellent rubber properties such as rubber elasticity and excellent moldability can be obtained.

By blending the components (b), (d) and (e) in the above range, a composition having excellent rubber properties such as rubber elasticity and excellent fluidity and moldability can be obtained.

By blending the component (c) within the above range, the moldability and the thermal adhesiveness to the resin or metal become excellent.

Further, fillers such as calcium carbonate, calcium silicate, clay, kaolin, talc, silica, diatomaceous earth are used within a range that does not impair the fluidity (moldability), rubber property and oil resistance of the produced elastomer composition. ,
Mica powder, asbestos, alumina, barium sulphate, aluminum sulphate, calcium sulphate, basic magnesium carbonate, molybdenum disulfide, graphite, glass fibers, glass spheres, shirasu balloons, carbon fibers, etc. or colorants such as carbon black, titanium oxide. , Zinc flower,
Red iron oxide, ultramarine blue, navy blue, azo pigment, nitroso pigment, lake pigment, phthalocyanine pigment and the like can be added.

In the present invention, known heat-resistant stabilizers such as phenol-based, sulfite-based, phenylalkane-based, phosphite-based or amine-based stabilizers, antiaging agents, weathering stabilizers, antistatic agents, metal soaps, lubricants such as waxes, etc. Etc. can be compounded to the extent that they are used in olefin resin or olefin copolymer rubber.

In the present invention, a modified polyolefin-based elastomer is produced by dynamically heat-treating a blend of the above-described components in the presence of an organic peroxide to partially crosslink.

Dynamically heat treating means kneading in a molten state.

Examples of the organic peroxide used in the present invention include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, and 2,5-dimethyl-2,5. -Di (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylpenoxyisopropyl) benzene, 1,1-bis (ter
t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert -Butyl peroxybenzoate, te
rt-butyl perbenzoate, tert-butyl peroxyisopropyl carbonate, diacetyl peroxide,
Lauroyl peroxide, tert-butylcumyl peroxide and the like can be mentioned.

Of these, odor and scorch stability are 2,5.
-Dimethyl-2,5-di (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene , 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, and n-butyl-4,4-bis (tert-butylperoxy)
Valerate is preferred, and 1,3-bis (tert-butylperoxyisopropyl) benzene is most preferred.

The blending amount of the organic peroxide is selected so as to be in the range of 0.05 to 3% by weight, preferably 0.1 to 1% by weight, based on the total amount of the components (a), (b) and (c). When the blending amount is within the above range, the thermoplastic elastomer obtained has sufficient heat resistance, tensile properties, rubber properties such as elastic recovery and impact resilience, and strength, and also has excellent moldability.

As the kneading device, conventionally known devices such as an open-type mixing roll, a non-open-type Banbury mixer, an extruder, a kneader, and a continuous mixer can be used. Among these, it is preferable to use a non-open type apparatus, and it is preferable to knead under an inert gas atmosphere such as nitrogen or carbon gas. The kneading is carried out at a temperature at which the half-life of the organic peroxide to be used is less than 1 minute, usually at 150 to 280 ° C., preferably at 17 ° C.
0 to 240 ° C., 1 to 20 minutes, preferably 3 to 10
Mixing may be performed for a minute.

In the present invention, sulfur, p-quinonedioxime, p, p ′ are used in the partial crosslinking treatment with the organic peroxide.
-Dibenzoylquinone dioxime, N-methyl-N, 4-
A peroxy crosslinking aid such as dinitrosoaniline, nitrobenzene, diphenylguanidine, trimethylolpropane-N, N'-m-phenylenedimaleimide, or
Multifunctional methacrylate monomer such as divinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate, polyfunctionality such as vinyl butyrate or vinyl stearate Vinyl monomers can be blended. With such a compound, a uniform and mild crosslinking reaction can be expected. In particular, in the present invention, when divinylbenzene is used, it is easy to handle and has good compatibility with the olefin rubber and olefin plastic containing the object to be treated as a main component, and also has an organic peroxide solubilizing action, and a peroxide. It is most preferable because it acts as a dispersion aid of the above, and thus a composition having a uniform cross-linking effect by heat treatment and having a well-balanced fluidity and physical properties can be obtained. In the present invention, the compounding amount of such a crosslinking assistant or polyfunctional vinyl monomer is preferably in the range of 0.1 to 2% by weight, particularly 0.3 to 1% by weight, based on the whole object to be treated. As a result, it is possible to obtain a composition which has excellent fluidity and does not cause a change in physical properties due to heat history at the time of processing and molding the composition.

In order to accelerate the decomposition of organic peroxides, tertiary amines such as triethylamine, tributylamine, 2,4,6-tris (dimethylamino) phenol, aluminum, cobalt, vanadium, copper, calcium, zirconium, manganese, Decomposition accelerators such as naphthenates such as magnesium, lead and mercury can also be used.

The kneading is preferably carried out in a non-open type apparatus, preferably in an inert gas atmosphere such as nitrogen or carbon dioxide gas. The temperature is a temperature at which the half-life of the organic peroxide used is less than 1 minute, usually 150 to 280 ° C., preferably 170 to 2 ° C.
The kneading time at 40 ° C. is usually 1 to 20 minutes, preferably 1 to 10 minutes. The applied shearing force is usually 10 at the shear rate.
-10 ⁴ sec ^-1 , preferably 10 ² -10 ³ sec ^-1 is selected.

As a kneading apparatus, a mixing roll, an intensive mixer, for example, a Banbury mixer, a kneader, a single-screw or twin-screw extruder, etc. can be used, but a non-open type is preferred.

As described above, by the dynamic heat treatment in the presence of the organic peroxide, a partial cross-linking is performed, and a polyolefin-based elastomer graft-modified with the component (c) is obtained.

In the present invention, the fact that the graft-modified polyolefin elastomer (A) is partially crosslinked means that the gel content measured by the following method is 20% or more, preferably 20 to 99.5%, particularly preferably 45 to 98%. When it is within the range of.

Measurement of gel content Weigh 100 mg of thermoplastic elastomer sample and
What was cut into 0.5 mm × 0.5 mm × 0.5 mm strips was immersed in 30 ml of cyclohexane in a closed container at 23 ° C for 48 hours, then the sample was taken out on a filter paper and kept at room temperature for 72 hours or more at a constant weight. Dry until

From the weight of this dry residue, all cyclohexane insoluble components (fibrous filler, filler,
Pigment, etc.) and the weight of the olefin-based plastic component in the sample before immersion in cyclohexane.
It is referred to as “corrected final weight (Y)”.

On the other hand, the weight of the peroxide-crosslinking olefin-based copolymer rubber in the sample, "that is, from the weight of the sample, the cyclohexane-soluble component (for example, mineral oil or plasticizer) and the olefin-based plastic component other than the peroxide-crosslinking-type olefin-based copolymer rubber , And the weight of cyclohexane-insoluble components (fibrous fillers, fillers, pigments, etc.) other than the polymer component] are defined as “corrected initial weight (X)”.

 Here, the gel content is calculated by the following formula.

Thermoplastic Elastomer Composition The thermoplastic elastomer composition of the present invention is obtained by blending the graft-modified polyolefin elastomer (A) and the polyamide (B) in a weight ratio of A: B = 60: 40 to 90:10. It was obtained.

By blending the components (A) and (B) in the above proportions, a thermoplastic elastomer composition having excellent oil resistance, mechanical strength, and heat aging resistance can be obtained.

The content of the grafted component (c) in the thermoplastic elastomer composition is measured by an infrared absorption analysis method or a chemical analysis method.

Polyamide (B) As the polyamide (B) in the present invention, hexamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4- or 2,4,4-trimethylhexamethylenediamine, 1,3- or 1 Aliphatic, alicyclic and aromatic diamines such as 1,4-bis (aminomethyl) cyclohexane, bis (p-aminocyclohexylmethane), m- or p-xylylenediamine and adipic acid, suberic acid, sebacic acid , Polyamides obtained by polycondensation with aliphatic, alicyclic, aromatic and other dicarboxylic acids such as cyclohexanedicarboxylic acid, terephthalic acid and isophthalic acid, aminocarboxylic acids such as ε-aminocaproic acid and 11-aminoundecanoic acid Obtained from lactams such as polyamide, ε-caprolactam, ω-laurolactam obtained by condensation Examples include polyamides, copolymerized polyamides containing these components, and mixtures of these polyamides. Specific examples include nylon 6, nylon 66, nylon 610, nylon 9, nylon 11, nylon 12, nylon 6/66, nylon 66/610, nylon 6/11. Among these, nylon 6 and nylon 6 are preferred in terms of good mechanical strength and heat resistance of the thermoplastic elastomer composition.
66 is preferred.

The modified polyolefin elastomer (A) and the polyamide (B) may be mixed by first mixing them with a Henschel mixer, a V-type blender, a ribbon blender, a tumbler blender, etc., and then uniaxially extruding the mixture at a temperature higher than the melting point of the polyamide. Examples of the method include melt-mixing with a machine, a twin-screw extruder, a kneader, a Banbury mixer, and the like, and granulating or pulverizing.

Further, the composition of the present invention may contain the above-mentioned filler which can be incorporated in the partially cross-linked graft-modified thermoplastic elastomer composition.

(Functions and Effects) The thermoplastic elastomer composition of the present invention thus obtained has excellent moldability and can be molded by an apparatus used for ordinary thermoplastics, and is suitable for extrusion molding, calender molding, injection molding and the like. Is suitable.

Further, the thermoplastic elastomer composition of the present invention comprises at least one kind selected from the group consisting of unsaturated carboxylic acids such as maleic anhydride or derivatives thereof, unsaturated epoxy monomers and unsaturated hydroxy monomers. Blended composition of both components consisting of modified polyolefin-based thermoplastic elastomer graft-modified with a monomer and polyamide, the composition has a significantly strengthened interface, resulting in excellent oil resistance and mechanical strength. , Interior seats,
It can be suitably used for applications such as mudguards), industrial parts (pressure hoses, gaskets, diaphragms, etc.), electronic / electrical device parts, building materials and the like.

In the present invention, the content ratio of the component (a) and the component (b) in the thermoplastic elastomer composition can be measured by the D.S.C method and / or the infrared absorption analysis method, and the ( The content of the components d) and (e) can be measured by a solvent extraction method (Soxhlet extraction method (solvent: acetone)) and / or an infrared absorption analysis method.

Example 1 Ethylene content 70 mol%, iodine value 12, Mooney viscosity,
ML _{1 + 4} (100 ℃) 120 ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber (hereinafter EPDM
(Abbreviated as (1)) 80 parts by weight, MFR (ASTM D1238-65T, 230
℃ 13), 20 parts by weight of isotactic polypropylene (hereinafter abbreviated as PP) having a density of 0.91 g / cm ³ is kneaded in a Banbury mixer in a nitrogen atmosphere at 180 ° C. for 5 minutes, and then rolled to form a sheet. Square pellets were made with a sheet cutter. Next, this square pellet, 0.3 parts by weight of 1,3-bis (tert-butylperoxyisopropyl) benzene (hereinafter abbreviated as peroxide (A)), divinylbenzene (hereinafter DVB)
0.5 part by weight, maleic anhydride (hereinafter abbreviated as MAH)
0.5 part by weight was mixed by stirring with a Henschel mixer. Next, this mixture was extruded at 220 ° C. in a nitrogen atmosphere with a uniaxial extractor having a screw diameter of 50 mm and L / D = 30 to produce a graft-modified polyolefin elastomer (A). And
The gel content of the copolymer rubber in the modified polyolefin elastomer (A) was measured by the method described above, and the measured values are shown in Table 1.

Next, this modified polyolefin elastomer (A) 82
Parts by weight and polyamide (B) (Unitika nylon 6A1030)
15 parts by weight of BRF) was extruded at 250 ° C. in a nitrogen atmosphere with a uniaxial extruder having L / D = 30 and a screw diameter of 50 mm. The obtained thermoplastic elastomer was compression molded at 250 ° C. to prepare a sheet for measuring physical properties, and the following physical properties were measured. The results are shown in Table 1.

Oil resistance: ΔV% According to JIS K6301, it was immersed in JIS No. 3 oil at 50 ° C. for 7 days, and the volume increase rate (percent) after immersion was measured with respect to before immersion.

Strength: T _B kgf / cm ^{2 Based on} JIS K6301, the tensile strength at break was measured at a tensile speed of 200 mm / min.

Flexibility: Torsional rigidity kgf / cm ² Compliant with ASTM D1043 Formability: MFRg / 10min Compliant with ASTM D1238 230 ℃, 2.16kg Heat aging resistance: A _R (E _B )% Compliant with JIS K6301, Gear at 135 ℃ The sample was placed in an oven for 7 days and the ratio (retention rate / percentage) to the elongation at break before aging was measured.

Comparative Example 1 Example 1 was repeated except that the amount of maleic anhydride was set to zero.

Example 2 Example 1 was repeated except that the amount of DVB was set to zero and the modified polyolefin elastomer (A) was 70 parts by weight and the polyamide (B) was 30 parts by weight.

Comparative Example 2 Ethylene content 70 mol%, iodine value 12, Mooney viscosity ML
_{1 + 4} (100 ° C) 120 pellet ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber (hereinafter abbreviated as EPDM (2)) 80 parts by weight, PP 20 parts by weight, peroxide (A) 0.3 parts by weight Parts, 0.5 parts by weight of MAH and 0.5 parts by weight of DVB were mixed by stirring with a Henschel mixer. Next, a modified polyolefin elastomer (A) was produced from these mixtures by a twin-screw extruder with L / D = 44 and a screw diameter of 53 mm at 220 ° C. in a nitrogen atmosphere, and 55 parts by weight of the modified polyolefin elastomer (A) was added to the polyamide. Example 1 was repeated except that the amount of (B) was changed to 45 parts by weight.

Examples 3, 4 and Comparative Example 3 The amount of peroxide (A) was 0.6 parts by weight, respectively.
The amount of MAH, modified polyolefin elastomer (A), or oliamide (B) is 1 part by weight and 1.5 parts by weight.
The same procedure as in Example 1 was carried out except that the table was used.

Examples 5, 6, 7 and Comparative Examples 4, 5 EPDM (1), PP were carried out in the same manner as Comparative Example 2 except that the compounding amounts of PP were as shown in Table 1. Example 8 Modified polyolefin elastomer (A) When manufacturing, in addition to EPDM (1) and PP, butyl rubber (made by Esso
IIR-065, unsaturation 0.8 mol%, hereinafter abbreviated as IIR) and paraffin-based process oil are blended as shown in Table 1 to obtain a modified polyolefin elastomer (A) and polyamide (B).
The same procedure as in Example 1 was carried out except that the compounding amount was changed as shown in Table 1.

Example 9 0.5 parts by weight of MAH in place of 0.5 parts of glycidyl methacrylate
The same procedure as in Example 8 was carried out except that the parts by weight were compounded.

Examples 10 and 12 EPDM (1), PP, IIR, paraffin-based process oil, MAH, modified polyolefin-based elastomer (A),
The same procedure as in Example 8 was carried out except that the compounding amount of polyamide (B) was as shown in Table 1.

Examples 11 and 13 EPDM (1), PP, IIR, paraffin-based process oil, glycidyl methacrylate, modified polyolefin-based elastomer (A), polyamide (B) were mixed in the first amount.
The procedure was performed in the same manner as in Example 9 except as shown in the table.

Example 14 The procedure of Example 8 was repeated except that maleic anhydride was changed to hydroxypropyl methacrylate.

Example 15 The procedure of Example 12 was repeated except that maleic anhydride was changed to hydroxypropyl methacrylate.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI technical display area C08L 77:00) (56) References JP-A-60-76557 (JP, A) JP-A-59 -164359 (JP, A) JP 58-206667 (JP, A) JP 55-80435 (JP, A) JP 55-18448 (JP, B2) JP 58-46138 (JP, B2) )

Claims (4)

[Claims] 1. (a) 95 to 60 parts by weight of a peroxide-crosslinking olefin-based copolymer rubber, (b) 5 to 40 parts by weight of an olefin-based plastic, and the total amount of (a) component and (b) component is 100. Parts by weight) (c) 0.01 to 10 parts by weight of at least one monomer selected from the group consisting of unsaturated carboxylic acids or derivatives thereof, unsaturated epoxy monomers and unsaturated hydroxy monomers, A partially crosslinked graft-modified polyolefin elastomer (A) obtained by dynamically heat treating the blended product in the presence of an organic peroxide, and a polyamide (B) have a ratio of A: B = 60: 40 to A thermoplastic elastomer composition, which is compounded in a weight ratio of 90:10. 2. The blended product further comprises (d) 100 parts by weight or less of a peroxide-non-crosslinked rubber-like substance, and / or 100 parts by weight of the total amount of the components (a) and (b). (E) 200 parts by weight or less of a mineral oil type softening agent is contained, The thermoplastic elastomer composition according to claim 1. 3. The thermoplastic elastomer composition according to claim 1, wherein the (b) olefin-based plastic is a peroxide-decomposable olefin-based plastic. 4. The thermoplastic elastomer composition according to claim 3, wherein the olefin-based plastic (b) is isotactic polypropylene.