JPH08283492A - Thermoplastic elastomer having low creep property and low-temperature impact resistance - Google Patents

Abstract

PURPOSE: To obtain a thermoplastic elastomer by blending an ethylene/α olefin/ nonconjugated diene copolymer rubber with a crystalline olefin-based resin, a prescribed crosslinking agent, a specific catalyst and a compatibilizing agent, excellent in flexibility and heat-resistance creep, etc., despite of being thermoplastic. CONSTITUTION: This thermoplastic elastomer is obtained by blending (A) 100 pts.wt. of an ethylene-α-olefin-nonconjugated diene copolymer rubber with (B) 5-300 pts.wt. of a crystalline olefin-based resin, (C) 0.5-30 pts.wt. an organopolysiloxane-based crosslinking agent containing an SiH group in the molecule of the formula ((m) is 5-400; R1 to R7 are each H, an alkyl, an aryl, etc.), (D) 0.001-2 pts.wt. of a VIII group transition metal-based hydrosilylated catalyst and (E) 0.5-20 pts.wt. of a compatibilizing agent and dynamically heat- treating the mixture.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic elastomer having stable low creep properties and low temperature impact resistance. More specifically, it is highly flexible, has excellent rubber elasticity over a wide temperature range, high-temperature creep performance, low-temperature impact resistance, mechanical strength, molding processability, and, despite being a thermoplastic elastomer, has good oil resistance and light discoloration resistance. The present invention relates to a novel thermoplastic elastomer which has extremely excellent toning property and can be used as a material for various molded products.

[0002]

2. Description of the Related Art In recent years, thermoplastic elastomers, which are rubber-like soft materials and do not require a vulcanization step and have the same moldability as thermoplastic resins, are used in automobile parts, home electric appliances parts, wire coating materials and medical parts. It is used in fields such as, sundries and footwear. As a typical example of the structure of a thermoplastic elastomer, there is a type in which hard segments and soft segments are alternately contained in a copolymer chain as disclosed in JP-A-61-34050. Various grades of these are manufactured by varying the proportion of each segment, from those with high flexibility to those with rigidity. In addition, there are other types of thermoplastic elastomers derived from cheap and readily available source materials.
That is, as disclosed in JP-B-53-21021, a thermoplastic blend of a monoolefin copolymer rubber and a polyolefin resin partially crosslinked with an organic peroxide, or a monoolefin copolymer rubber and a polyolefin resin This is a composition in which an organic peroxide is used as a cross-linking aid and melt-kneading is performed to partially cross-link the composition. However, in the case of a thermoplastic elastomer having a structure in which hard segments and soft segments are alternately contained in the former copolymer chain, a large amount of soft segments must be included in order to obtain a flexible thermoplastic elastomer. Is required. Usually, the soft segment has low tensile strength and poor heat resistance, fluidity, and oil resistance. Therefore, a flexible thermoplastic elastomer composition containing a large amount of such soft segment also has low tensile strength and heat resistance. ,
It has the drawbacks of poor fluidity and oil resistance and cannot be used for a wide variety of applications. In addition, when synthesizing a flexible grade by a multi-step synthesis method, it is necessary to synthesize the hard segment and the soft segment separately, which makes the polymerization equipment very complicated and the characteristics and proportion of each segment at the polymerization stage. Is very difficult to control, and defective products may occur when switching grades. Furthermore, the recovery of the produced polymer is very difficult because it contains a large amount of rubber-like properties.

In the latter case, the thermoplastic elastomer having a structure in which the monoolefin copolymer rubber in the component is partially crosslinked is insufficient in oil resistance and shape recoverability at high temperature because of the partial crosslinking. Therefore, it cannot be used for various purposes over a wide range. In addition, since an organic peroxide is used, a polymer chain is cut off by radicals caused by the organic peroxide at the same time as crosslinking, resulting in a decrease in mechanical strength. A means for overcoming this drawback is disclosed in Japanese Patent Publication No. 58-46138. That is, it is a means of preferentially promoting only the crosslinking of the monoolefin copolymer rubber by using the heat-reactive alkylphenol resin as the crosslinking agent. Although the thermoplastic elastomer obtained by this means is completely crosslinked, it has improved oil resistance and shape recovery at high temperatures,
It is still insufficient compared to vulcanized rubber. Further, USP4803244 proposes a method of using an organosiloxane compound instead of an alkylphenol resin as a crosslinking agent. This method can preferentially proceed only the crosslinking of the monoolefin copolymer rubber in the same manner as the alkylphenol resin crosslinking, and obtains a material excellent in oil resistance, shape recovery at high temperature, light discoloration resistance, etc. Because
It can be used for home appliance parts, wire coating, etc., which require flexibility in toning. However, since a compatibilizer is not added in this method, the adhesiveness between the rubber and the resin is not always sufficient, so that it is used for automobile parts where low temperature impact resistance is particularly required, for example, materials for automobile airbag covers. Cannot be used. Further, Japanese Patent Publication No. 7-15031 describes a method of using a organosiloxane having a specific structure and a rhodium-based catalyst as a method of crosslinking a reactive polyolefin. The purpose of this patent is not to cause foam formation inside the molded product, but even when the cross-linking agent and rhodium-based catalyst of the patent are used, when heat treatment is carried out, the creep property remarkably deteriorates and the level of vulcanized rubber is the same. It is not possible to produce elastomers with low creep properties.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in order to develop stable low creep property and low temperature impact resistance comparable to vulcanized rubber, which has been difficult with conventional thermoplastic elastomer compositions. While maintaining good rubber properties over the temperature range, it has excellent low-temperature impact resistance, wide coloring freedom, low residual heavy metal substances, etc. It is intended to provide a thermoplastic elastomer which can be used in various applications over a wide range including applications where long-term reliability is required.

[0005]

Means for Solving the Problems That is, the present invention provides an ethylene-α-olefin-non-conjugated diene copolymer rubber (a) 1.
5 parts by weight of crystalline olefin resin (b) 5
To 300 parts by weight, 0.5 to 30 parts by weight of an organosiloxane cross-linking agent having an SiH group in the molecule (c), 0.001 to 2 parts by weight of a Group 8 transition metal hydrosilylation catalyst (d), and 0.5 to 20 parts by weight of the compatibilizer (e) is mixed,
A thermoplastic elastomer obtained by dynamically heat-treating, wherein a compound having a structure represented by the following structure is used as an organosiloxane cross-linking agent (c) having an SiH group in a molecule. Yes (1) m is an integer of 5 or more and 400 or less (2) R _{1 to} R ₇ are hydrogen, an alkyl group, an alkoxy group,
An aryl group or an aryloxy group or 30 parts of paraffinic oil (f) is added to the above composition.
It is a thermoplastic elastomer characterized by using ˜300 parts by weight.

The present invention can improve the cross-linking density among the organosiloxane compounds having SiH groups in the molecule, which have excellent photochromic resistance and biocompatibility as a cross-linking agent and have the property of selectively cross-linking rubber. , And those having a specific molecular structure capable of stably maintaining the crosslink density thereof, also selectively crosslink the rubber by crosslinking while melt-kneading using a hydrosilylation catalyst, and further by a compatibilizer, The technical idea of achieving high dispersion of rubber particles, which is essential for low creep properties and low-temperature impact resistance expression, which could not be achieved only by mechanical shearing force, and also improves the adhesive strength of the interface. Based on this research, as a result, while maintaining good rubber properties equivalent to or better than vulcanized rubber over a wide temperature range, low creep, low temperature impact resistance, toning, good Applications where molded appearance is obtained even applied can for various applications over a wide range of including, moreover,
With a normal kneader, the shear rate is 100-1000 / sec
The present inventors have found that they can be achieved under extremely common-sense melt-kneading conditions such as the above, and based on this finding, they have further advanced various studies and completed the present invention. or,
Since the thermoplastic elastomer composition produced by the present invention is subjected to the compatibilization method, it was found that the morphology change is unlikely to occur even after the annealing treatment, and as a result, the long-term reliability is also very excellent. The present invention will be described below more specifically and in detail.

The ethylene-α-olefin-non-conjugated diene copolymer rubber (a) used in the present invention is ethylene,
It is composed of α-olefins and non-conjugated dienes, and α-olefins having 3 to 15 carbon atoms are suitable. Non-conjugated dienes include dicyclopentadiene, 1,4-hexadiene,
Ethylidene norbornene, methylene norbornene and the like can be used. In the present invention, propylene is suitable as the α-olefin from the viewpoint of easy availability and improvement of impact resistance. Therefore, EPDM is preferred. The copolymer rubber has an ethylene / α / olefin ratio of 50/50 to 9 by weight.
0/10, and more preferably 60/40 to 80/20. Here, the Mooney viscosity of the rubber used, ML1 + 4
(125 ° C.) is 10 to 120, preferably 40 to 100
You can choose from the range of. The Mooney viscosity is an index of the molecular weight of rubber and processing characteristics. Here, when the Mooney viscosity of the rubber itself is less than 10, it means that the rubber molecular weight is very small, and the molecular weight of the crosslinked rubber tends to be small and the compression set tends to be large. On the other hand, if it exceeds 120, the molding processability is remarkably deteriorated, but the component in which the component (e) is melt-kneaded (oil extended) in advance to adjust the apparent Mooney viscosity to 120 or less is commercially available. . Further, the iodine value of the rubber is an index of reactivity, and the larger the value, the higher the activity. The rubber type used in the present invention is preferably 10 to 30, more preferably 10 to 20.

Next, the crystalline olefin resin (b) used in the present invention is effective in improving the processability and heat resistance of the resulting composition. Here, the crystalline olefin resin (b) is, for example, a random or block copolymer of polyethylene, polypropylene or propylene and a small amount of other α-olefin, specifically, polypropylene-ethylene copolymer, propylene-1. -Hexene copolymer, propylene-4-methyl-1-pentene copolymer, poly-4-methyl-1-pentene, polybutene-1 and the like can be mentioned. Among them, polypropylene or its copolymer is preferable, and its MFR (ASTM-D-1238L condition, 230 ° C.) is 0.1 to 50 g / 10 minutes, especially 0.5 to 30.
Those having a range of g / 10 minutes can be preferably used. The compounding amount of the crystalline olefin-based resin (b) is the rubber component (a) 10
It is compounded in the range of 5 to 300 parts by weight with respect to 0 parts by weight,
It is preferably compounded in the range of 10 to 200 parts by weight. Three
When the amount exceeds 100 parts by weight, the resulting elastomeric composition tends to have high hardness and lose flexibility,
If the amount is less than 5 parts by weight, the processability will be poor.

Next, the rubber crosslinking agent (c) used in the present invention is an organosiloxane compound having a SiH group and having a specific molecular structure capable of improving the crosslinking density. In the present invention, a selective addition reaction (hydrosilylation) of SiH groups to unsaturated hydrocarbons in a rubber component is used as a rubber crosslinking method. Generally, in order to produce a thermoplastic elastomer having low creep properties, it is said that the crosslink density needs to be 1 × 10 6 mol / ml or more. Further, in order to have a stable low creep property, it is necessary to keep the crosslink density stable. In order to achieve this crosslink density, organosiloxane compounds having various molecular structures were investigated, and as a result, it was found that organosiloxane compounds having the following structures were applicable.

[0010] (1) m is an integer of 5 or more and 400 or less (2) R _{1 to} R ₇ are hydrogen, an alkyl group, an alkoxy group,
Aryl group or aryloxy group That is, in one molecule of the organosiloxane compound, it is necessary that the number of SiH group-containing units is 5 or more and 400 or less in order to make the crosslinking points rigid to some extent. That is, when m is 4 or less, the number of cross-linking points is small, so the cross-linking density is lowered, and when it is 400 or more, the viscosity of the organosiloxane itself becomes too high and the fluidity deteriorates. If there is at least one unit that does not have a SiH group, it has a unit that cannot be added to the diene portion of the rubber, and the crosslinked structure does not become rigid, and the creep history remarkably deteriorates due to heat history. It should be noted that there is no inconvenience in blending several kinds of organosiloxane compounds having this structure.

The Group 8 transition metal-based hydrosilylation catalyst (d) used in the present invention is a Group 8 transition metal such as palladium, rhodium or platinum or a compound thereof among the catalysts for promoting the hydrosilylation reaction. A complex is mentioned. The most popular catalysts are dichlorobis (acetonitrile) palladium (II), chlorotris (triphenylphosphine) rhodium (I), chloroplatinic acid and the like. In order to disperse the cross-linking agent and the catalyst more highly, the cross-linking agent (c) for the rubber and the Group 8 transition metal hydrosilylation catalyst (d) are added to at least one selected from the liquid component and the solid component. It is preferable to use one that is dissolved or supported. As a specific method, it can be dissolved in a solvent such as acetone or isopropanol, calcium carbonate,
There is a method of supporting it on an inorganic filler such as silica, or supporting it on an inorganic filler such as silica in a state of being dissolved in an alcohol solvent. The solvent used here is not particularly limited, but needs to be relatively inert to the hydrosilylation reaction. Examples of the solvent type include hydrocarbon type, alcohol type, ketone type, ester type and the like. The concentration of the solution to be prepared is not particularly limited. Further, the inorganic filler is required to have adsorption ability, and examples thereof include calcium carbonate, carbon black, talc, mica, barium sulfate, natural silicic acid, synthetic silicic acid (white carbon), titanium oxide and the like. A known method can be used to prepare the supported catalyst.

The term "dynamically crosslinked thermoplastic elastomer composition" as used herein means that 1 g of the composition obtained in the present invention is refluxed with boiling xylene in a Soxhlet extractor for 10 hours, and the residue is a mesh of 80 mesh. The gel content is 100 times the ratio of the dry weight of the insoluble matter remaining on the mesh (g) / the weight of the component a contained in 1 g of the composition, and the gel content is at least 30%, preferably 50% or more. (However, insoluble components such as inorganic fillers are not included therein), and the crosslinking is performed during melt-kneading of the thermoplastic elastomer composition. In order to obtain such a dynamically crosslinked thermoplastic elastomer composition, the organosiloxane crosslinker (c) is used.
The compounding amount of 0.5 is 0.5 to 100 parts by weight of the component (a).
It can be suitably selected from 30 parts by weight, preferably 1 to 20 parts by weight, and its gel content can be adjusted. The catalyst (d) may be added in an amount of 0.001 to 2 parts by weight based on 100 parts by weight of the rubber component. In the case of a Group 8 transition metal-based catalyst as a catalyst, the addition amount is preferably 0.005 to 1 part by weight, more preferably 0.01 to 0.5 part by weight. When the amount is less than 0.001 part by weight, the crosslinking does not proceed at a practical speed. Also, 2
If it exceeds 5 parts by weight, not only there is no effect of increasing the amount, but also the deactivated catalyst becomes black-colored lumps and the appearance becomes poor, and heat treatment tends to cause undesired side reactions (decomposition of unreacted SiH groups, etc.).

The compatibilizer (e) used in the present invention is
The rubber and the thermoplastic resin each have a component having an affinity for each in the same molecule, and this acts as a surfactant, resulting in normal kneading conditions (shear rate:
100 to 1000 / sec) to finely disperse the crosslinked rubber to less than 30 microns, improve the adhesive strength at the interface between the crosslinked rubber and the thermoplastic resin, and significantly improve the low temperature impact resistance. Is added for the purpose. Generally, it is said that the mechanical strength and the low creep property are remarkably improved if the dispersed particle diameter of the rubber can be dispersed to several to sub μm. No particular limitation is imposed on the monomer, oligomer, or polymer having any structure as long as the object is met. As a general structure of the compatibilizer, the compatibilizing agent has components that are compatible with the ethylene-α-olefin-non-conjugated diene copolymer rubber (a) and the crystalline olefin resin (b), respectively, in the same molecule. In general, the compatibilizer is preferably a block copolymer, a random copolymer or a graft copolymer, which is polymerized from two or more kinds of monomers. Such a copolymer may be a commercially available product, or may be prepared by oneself. For example, a styrene-based copolymer can be given as an example of a commercially available copolymer. That is, styrene-butadiene copolymer and hydrogenated products thereof (including all random copolymers, block copolymers, graft copolymers, etc.) are mentioned, and more specifically, styrene-butadiene-styrene copolymers. Combined (SB
S), hydrogenated styrene-butadiene-styrene copolymer (SEBS), isoprene-styrene copolymer, hydrogenated isoprene-styrene copolymer (SEP), styrene-isoprene-styrene copolymer (SIS), hydrogenated Examples thereof include styrene-isoprene-styrene copolymer (SEPS). Above all, it significantly improves impact resistance at low temperature,
Styrenic elastomer preferably used is SEB
S, SEP and SEPS, among which the preferable styrene content is 10 to 80% by weight, more preferably 30 to 7%
It is 0% by weight, and more preferably 40 to 70% by weight.

Examples of the method for preparing the compatibilizer include (e-3), (e-4) and (e-5) shown below. (E-3) Polyethylene resin having an epoxy group as an essential component, polyethylene having a carboxylic acid anhydride and / or a carboxylic acid group in the molecule, an ethylene copolymer, a styrene block copolymer and / or a hydrogenated product thereof. ,
A compatibilizing agent (e-4) characterized in that at least one selected from carboxylic acid-modified resins such as styrene random copolymers and / or hydrogenated products thereof is melt-reacted (e-4) maleic anhydride in the molecule. Epoxy-modified resin such as polyethylene having an acid group as an essential component, epoxy group-containing polyethylene, ethylene copolymer, styrene block copolymer and / or its hydrogenated product, styrene random copolymer and / or its hydrogenated product A compatibilizer (e-5) characterized by being melt-reacted with at least one selected from the group consisting of polyethylene, an ethylene copolymer, a styrene block copolymer and / or A block with at least one resin selected from hydrogenated products, styrene random copolymers and / or hydrogenated products thereof. Compatibilizer obtained by dynamically heat-treating a metal compound in the presence of a peroxide Comprising a modified resin having a maleic anhydride group and an epoxy group used as a raw material for the compatibilizer (e-3) (e-4) The modified resin can be easily obtained by a known technique.
That is, it can be obtained by a method of graft copolymerization using a peroxide or the like or by copolymerization with a resin monomer component.
These may be commercially available products. Ethylene is used as the modified resin having a maleic anhydride group used in the present invention.
Acrylic acid / maleic anhydride terpolymer, ethylene
Ethyl acrylate / maleic anhydride terpolymer, ethylene / methacrylic acid / maleic anhydride terpolymer,
Polypropylene grafted with maleic anhydride, polyethylene grafted with maleic anhydride, ethylene-propylene copolymer grafted with maleic anhydride, styrene-ethylene / butylene-styrene block copolymer grafted with maleic anhydride, maleic anhydride Examples thereof include a styrene-ethylene / butylene-styrene random copolymer grafted with.

Examples of the epoxy modified resin used in the present invention include ethylene / glycidyl methacrylate copolymer, ethylene / acrylic acid / glycidyl acrylate terpolymer, ethylene / acrylate / allyl glycidyl ether terpolymer, ethylene / Methacrylate / glycidyl acrylate terpolymer, ethylene / propylene / glycidyl methacrylate terpolymer,
Glycidyl methacrylate grafted polypropylene, glycidyl methacrylate grafted styrene-ethylene / butylene-styrene block copolymer, glycidyl acrylate grafted styrene-
Examples include ethylene / butylene-styrene random copolymers.

The compatibilizing agents (e-3) and (e-4) of the present invention are obtained by using a batch type kneader to prepare a composition comprising the above-mentioned modified resin having a maleic anhydride group in the molecule and a resin having an epoxy group. It is obtained by performing a melt reaction at 150 to 250 ° C. for 5 to 30 minutes. At the time of melt-kneading, a remarkable increase in torque occurs, and it is considered that some reaction occurs between the modified resin having a maleic anhydride group in the molecule and the resin having an epoxy group. In addition, the compatibilizer (e-3) (e
When the infrared absorption spectrum of -4) was examined, the characteristic absorption of the epoxy group and maleic anhydride group contained in the raw material disappeared, and it is considered that a reaction occurred between the epoxy group and the maleic anhydride group. The compatibilizer (e-5) of the present invention contains polypropylene as an essential component, and comprises polyethylene, ethylene-propylene copolymer rubber, styrene block copolymer and / or hydrogenated product thereof, styrene random copolymer and / or hydrogenated product thereof. A batch-type kneading machine comprising a blend with at least one or more resins selected from the above, an organic peroxide such as an organic peroxide, an organic perester, and an azo compound, and if necessary, a cocatalyst such as a bismaleimide compound. It is obtained by melt-reacting at 150 to 250 ° C. for 5 to 30 minutes and co-crosslinking. Here, the amount of the organic peroxide catalyst added was 0.0001 with respect to 100 parts by weight of the blend.
~ 2 parts by weight are preferred. Where peroxide catalyst 0.00
If it is less than 01 parts by weight, the reaction does not proceed at a practical rate.
Further, if it exceeds 2 parts by weight, not only the effect of increasing the amount but also unfavorable side reactions (decomposition of polypropylene, gelation reaction, etc.) tend to occur.

Here, for the compatibilizers (e-3) and (e-4), the ratio of the epoxy-modified resin and the maleic anhydride-modified resin is used, and for the (e-5), polypropylene and a specific group are used. The ratio with one or more resins selected from
0:90 to 90: 10% by weight, preferably 70:30 to
30: 70% by weight, more preferably 60:40 to 40:
It is compounded in the range of 60% by weight. If the proportion of either component is less than 10% by weight, the effect of improving the adhesive strength at the interface becomes insufficient, and the effect of improving the low temperature impact resistance of the thermoplastic elastomer of the present invention tends to become insufficient. Further, the addition amount of the compatibilizer (e) is the rubber component (a) + the resin component (b).
The total amount is 0.5 to 20 parts by weight, preferably 1 to 15 parts by weight, and more preferably 2 to 10 parts by weight. If it is less than 0.5 parts by weight, the effect of lowering the interfacial tension tends to decrease, and therefore the effect of improving the adhesive strength at the interface tends to decrease, and the dispersed particles of the vulcanized rubber tend to increase. The effect of improving the low temperature impact resistance of the thermoplastic elastomer is insufficient, and the appearance of the molded article tends to be deteriorated. On the other hand, if it exceeds 20 parts by weight, the hardness of the thermoplastic elastomer of the present invention becomes so hard that the low temperature impact resistance is deteriorated and the rubber elasticity as an elastomer tends not to be exhibited.

Paraffinic oil (f) used in the present invention
Has an effect of adjusting the hardness of the obtained composition and giving flexibility, and is added as necessary. Generally used for softening, increasing volume, and improving processability of rubber, a softener for mineral oil rubber called process oil or extender oil is a mixture of aromatic ring, naphthene ring, and paraffin chain. Paraffin chains have 50% or more of the total number of carbon atoms are called paraffins, and those with 30 to 45% naphthene ring carbons are naphthenes, and aromatics with more than 30% aromatic ring carbons. It is considered a system.
The oils used in the present invention are preferably paraffinic oils in the above categories, and naphthenic and aromatic oils are not preferable in terms of dispersibility and solubility. The paraffinic rubber softener has a kinematic viscosity of 20 to 50 at 37.8 ° C.
0 cst, pour point -10 to -15 ℃ and flash point 1
70-300 degreeC is shown. The preferable blending amount of the paraffinic oil (f) is 3 with respect to 100 parts by weight of the rubber component (a).
0 to 300 parts by weight, more preferably 30 to 25
0 parts by weight. If the composition exceeds 300 parts by weight,
It tends to cause bleeding out of the softening agent, may cause tackiness in the final product, and tends to deteriorate mechanical properties. Further, if it is less than 30 parts by weight, it is meaningless to add it.
Further, the component (a) oil-extended with paraffin oil is commercially available, and a method of adding a predetermined amount using this can also be suitably adopted.

The thermoplastic elastomer composition obtained according to the present invention exhibits excellent mechanical strength and compression set at high temperature, as compared with a thermoplastic elastomer composition partially crosslinked by using a known organic peroxide. Giving the composition.
Further, compared to a thermoplastic elastomer composition that is completely crosslinked using a heat-reactive alkylphenol resin of the known art,
A composition having remarkably excellent resistance to light discoloration is provided. Further, the adhesiveness of the interface is remarkably improved, and as in the known art,
Compared to a thermoplastic elastomer composition obtained by crosslinking by hydrosilylation using a Group III transition metal catalyst such as chloroplatinic acid, the low temperature impact resistance is significantly improved and the appearance of the molded product is improved. Remarkably improved. In addition to the above-mentioned components, the composition of the present invention may further contain an inorganic filler, if necessary, especially for applications in which color matching is unnecessary. This inorganic filler not only has the advantage of reducing the product cost as an extender, but also has the advantage of giving a positive effect to quality improvement (heat-resistant shape retention, flame retardancy impartation, etc.). Examples of the inorganic filler include calcium carbonate, carbon black, talc, magnesium hydroxide, mica, barium sulfate, natural silicic acid, synthetic silicic acid (white carbon), titanium oxide, and the like, and the carbon black includes channel black and furnace. Black etc. can be used. Among these inorganic fillers, talc and calcium carbonate are economically advantageous and preferable. Further, various additives can be added if necessary. Examples of additives include nucleating agents, external lubricants, internal lubricants, hindered amine light stabilizers, hindered phenolic antioxidants, colorants, flame retardants, silicone oils (organosiloxane, silane coupling agents, etc.). May be added. It is also possible to blend other thermoplastic resins such as styrene block copolymer (SBC), ethylene-α · olefin copolymer, and thermoplastic urethane resin.

The method for producing the composition of the present invention includes:
All general methods used for producing ordinary resin compositions and rubber compositions can be employed. Basically, it is a mechanical melt-kneading method, and a single-screw extruder, a twin-screw extruder, a Banbury mixer, various kneaders, brabenders, rolls and the like are used for these. At this time, the addition order of each component is not limited, for example, rubber, resin components are premixed in advance with a mixer such as a Henschel mixer, a blender and melt-kneaded with the above kneader, and then a crosslinking agent and a catalyst component are added. When the rubber is added and dynamically crosslinked, or when the scorch time of the rubber to be used is sufficiently long, an addition method such as melt-kneading components other than the catalyst in advance and further adding a catalyst and melt-kneading can be adopted. At this time, the temperature for melt-kneading can be suitably selected from the range of 180 to 300 ° C. and the shear rate of 100 to 1000 / sec. Furthermore, first, (a) (c) (d)
The thermoplastic elastomer of the present invention can also be obtained by first producing a crosslinked rubber product using the component (e), adding the crushed product of the rubber crosslinked product to the remaining components, and melt-kneading. The method for obtaining the rubber cross-linked product is not particularly limited, and any method used for producing a usual thermosetting resin composition or thermosetting rubber composition can be adopted. The crushing of the crosslinked rubber produced through the above steps can be achieved by a usual crushing method. That is, a crusher, particularly a freeze crushing method using dry ice or liquid nitrogen is preferably used. Further, an inorganic filler or the like can be used as a powdering agent. At this time, when a batch-type kneader such as a kneader is used, the composition is thermosetting when the rubber is sufficiently cured, and the composition is roughly crushed in the kneader without providing a crushing step. Particularly preferably used.

Since the dynamically crosslinked elastomer composition obtained here is thermoplastic, it can be molded by using a commonly used thermoplastic resin molding machine, such as injection molding, extrusion molding and calender molding. Various molding methods such as blow molding can be applied. That is, the shear rate dependency of the melt viscosity is particularly large, the viscosity is low and the fluidity is high in the injection molding region of high shear rate, and the injection molding can be easily performed like a general-purpose resin. Further, in the extrusion / blow molding region of medium shear rate, the viscosity becomes high to some extent, which leads to low drawdown, and therefore extrusion / blow molding is also easy. Hereinafter, the present invention will be described in more detail with reference to Examples.
It is not limited to these examples.

[0022]

EXAMPLES The components blended in the examples and comparative examples shown below are as follows. <Component a (1): EPDM> Ethylene-propylene-ethylidene norbornene copolymer rubber KELTAN K712 manufactured by Idemitsu DSM Co., Ltd. [Propylene content: 40% by weight, Mooney viscosity ML1 + 4]
(125 ° C): 63, iodine value: 16, Tg: -53
C] <Component a (2): EPDM> Oil-extended ethylene-propylene-ethylidene norbornene copolymer rubber KELTAN K509X100 manufactured by Idemitsu DSM KK [Propylene content: 30% by weight, Mooney viscosity ML1 + 4]
(125 ° C): 100, iodine value: 26, Tg: -45
C, paraffin oil oil extension: 100 parts by weight] <Component b (1): H-PP> Homotype polypropylene resin, W manufactured by Sumitomo Chemical Co., Ltd.
501 [MFR (230 ° C.) = 8.0 g / 10 minutes, heat distortion temperature: 115 ° C.] <Component b (2): B-PP> Block type polypropylene resin, Sumitomo Chemical Co., Ltd.
AV664B [MFR (230 ℃) = 5.0g / 10min, heat distortion temperature: 122 ℃]

<Component c (1): SiH: m = 50> manufactured by Nippon Unicar Co., Ltd. <Component c (2): SiH: m = 15> Made by Nippon Unicar Co., Ltd. <Component c (3): SiH> Made by Nippon Unicar Co., Ltd. <Component c (4): SiH> Made by Nippon Unicar Co., Ltd. <Component c (5): SiH> Made by Nippon Unicar Co., Ltd.

<Component d (1): Catalyst> Chloroplatinic acid hexahydrate manufactured by Yasuda Chemical Co., Ltd. <Component d (2): Catalyst> 3% by weight of component d (1) 2-
A propanol solution was prepared, and 10 g of this solution was supported on 100 g of silica (Nipsil VN3 manufactured by Nippon Silica). <Component d (3): Catalyst> 1 g of the bis-cyclooctadiene rhodium salt was prepared by melt-kneading 1 g of low-density polyethylene (specific gravity: 0.923) in 500 g. <Component e-1: SEBS> Styrene-ethylene-butylene-styrene copolymer (S
EBS) Tuftec H1041 manufactured by Asahi Kasei Kogyo Co., Ltd. <Component e-4: PP-SEBS> Epoxy-modified styrene is added to 100 parts by weight of polypropylene oligomer having an average molecular weight of 4000 and modified with maleic anhydride (PP-MAH). After adding 80 parts by weight of a block copolymer Tuftec Z514 [manufactured by Asahi Kasei] and thoroughly mixing with a Henschel mixer, melt kneading with a kneader at about 200 ° C. for 20 minutes,
After forming into a roll sheet, it was cooled to room temperature and pelletized with a sheet pelletizer to obtain a compatibilizer e-4 of the present invention.
As a result of examining the infrared absorption spectrum of the compatibilizer e-4,
It is considered that the characteristic absorption of the epoxy group and the acid anhydride group contained in the raw material has disappeared, and a reaction has occurred between the epoxy group and the acid anhydride group. <Component f: Oil> Diana Process Oil PW-380 manufactured by Idemitsu Kosan [paraffin-based process oil, kinematic viscosity:
381.6 cst (40 ° C.), 30.1 (100 ° C.), average molecular weight 746, ring analysis value: CA = 0%, CN = 27%,
CP = 73%]

<< Examples 1 to 18 and Comparative Examples 1 to 12 >> c
After sufficiently dry blending all the components except the component and the d component, melt-knead them with a kneader at about 200 ° C. for 20 minutes, form a roll sheet, cool to room temperature, pelletize with a sheet pelletizer, and before dynamic crosslinking. A thermoplastic composition was obtained. The pellets were mixed with a considerable amount of the components c and d, and mixed again using a twin-screw kneader so that the resin temperature was 190 to 230 ° C. at a shear rate of 800 / sec and the heat was dynamically crosslinked. A plastic elastomer composition was obtained. Injection molding and extrusion molding were performed using this composition, and the following physical properties were evaluated. Examples were listed in Tables 1 and 2, and Comparative Examples were listed in Tables 3 and 4. (1) Hardness (JIS K6301 A type) (2) Tensile strength TS [MPa] and elongation Eb [%] (JI
SK6301, No.3 dumbbell) (3) Compression set CS [%] (JIS K6301, 2
5% compression −40 ° C. × 22 HR, 70 ° C. × 22 Hr and 100 ° C. × 400 Hr) (4) Oil resistance [%] (JIS K6301, No3 test oil (lubricating oil) is used, 70 ° C. for 2 hours, 50 × 50 x t
The test piece of No. 2 was immersed, and the weight change (%) before and after immersion was obtained. (5) Formability test (φ / mm = 2 using an extruder of 50 mm)
0 screw, 100 mm x t0.5 die, C / R = 3.0, kneading temperature 200 ° C, rotation speed 100r
Create a tape of 150 × 500 mm in pm, visually observe the surface, and remove the spots with a diameter of 100 microns or more.
When one or more was observed, it was rated as X, when one was observed, as Δ, and when not observed, as ◯. ) (7) Low temperature impact resistance (a test piece of 75 x 75 x t-1 is -60
After immersing in a dry ice methanol solution at 10 ° C. for 10 minutes, a DuPont drop ball impact test was conducted. When no crack was found after the test, it was marked with ◯, and when cracking was found, it was marked with x. [Test conditions Fishing weight: 500 g Tip sphere R: 3/16 Drop height:
1m]) (8) Long-term reliability ((3) after 100 ℃ x 1000hr treatment)
The permanent compression strain measurement was carried out according to. (JIS K63
01, 25% compression 70 ° C. × 22 Hr) When the absolute value of the residual rate of 80% or more was 30% or less and the performance of 80% or more was maintained, it was rated as “◯”, and in other cases, it was rated as “X”. (9) Light resistance to discoloration (exposed to 83 ° C. × 1000 Hr using a sunshine weatherometer, and a color difference of 3 or less compared with that before the treatment was evaluated as ○, and a color difference of more than 3 was evaluated as ×.)

Further, in Comparative Examples 1 and 2, the dynamic cross-linking was performed in the same manner as in the Example except that 2 parts by weight of an organic peroxide [dicumyl peroxide (DCP)] and 3 parts by weight of divinylbenzene (DVB) were used. Made by way. Furthermore, in Comparative Examples 3 and 4, the dynamic crosslinking was carried out by using a thermoreactive alkylphenol resin [Schenect
ady Chemicals SP1045] was used in the same manner as in Example except that 5 parts by weight of the ady Chemicals and 2 parts by weight of the crosslinking aid [stannous chloride] were used. In Comparative Examples 5 to 12, organosiloxane was used as the crosslinking agent, and the component d (3) shown in the examples was used as the catalyst. From these results, the thermoplastic elastomer composition dynamically crosslinked by using the organosiloxane compound having the specific structure of the present invention and the compatibilizer was added to the thermoplastic elastomer composition was prepared by blending the organic peroxide system of the known art. Mechanical strength and 70 ° C. higher than elastomer compositions, 10
It was clarified that a composition having a compression set at 0 ° C. and excellent oil resistance and having a vulcanized rubber equivalent or better was obtained. It was also found to have excellent low temperature impact resistance. Furthermore, it has been found that the composition of the present invention has good resistance to light discoloration, and thus has a large degree of freedom in toning, has stable low creep properties, and is extremely excellent in long-term reliability.

Table 1 Example 1 2 3 4 5 6 composition (parts by weight) EPDM 100 100 100 100 100 100 100 H-PP 20 100 270 20 50 50 SiH 1 5 25 1 5 28 catalyst 0.005 0.5 1.8 catalyst 7 7 7 SEBS 1 5 18 5 5 5 5 OIL 100 250 250 100 100 Physical properties Hardness 94 85 85 90 98 62 65 65 TS (MPa) 20 18 18 24 15 16 Eb (%) 250 300 400 200 570 550 CS (%) -40 ° C 19 19 21 21 21 19 CS (%) 70 ° C 17 18 18 16 16 13 12 CS (%) 100 ° C 21 19 20 22 16 17 17 Oil resistance (%) 15 19 10 10 11 11 9 Formability test ○ ○ ○ ○ ○ ○ ○ Low temperature impact resistance Properties ○ ○ ○ ○ ○ ○ Long-term reliability ○ ○ ○ ○ ○ ○ Light and color fastness ○ ○ ○ ○ ○ ○

Table 2 Example 7 8 9 10 11 12 Composition (parts by weight) EPDM 100 200 200 200 200 200 200 B-PP 10 100 270 50 50 50 SiH 0.5 5 25 1 1 5 25 Catalyst 0.5 0.5 10 80 10 10 10 PP- SEBS 1 5 18 5 5 5 5 OIL 150 50 150 Physical properties Hardness 97 87 87 93 82 67 67 55 TS (MPa) 23 21 21 21 18 16 16 Eb (%) 200 250 300 300 370 420 470 CS (%) -40 ° C 22 21 22 22 23 21 21 CS (%) 70 ° C 20 19 18 19 19 13 11 CS (%) 100 ° C 25 18 22 20 17 14 14 Oil resistance (%) 15 19 10 10 11 11 10 Moldability test ○ ○ ○ ○ ○ ○ Low temperature impact resistance Properties ○ ○ ○ ○ ○ ○ Long-term reliability ○ ○ ○ ○ ○ ○ Light and color fastness ○ ○ ○ ○ ○ ○

Table 3 Comparative Example 1 2 3 4 5 6 Composition (parts by weight) EPDM 100 100 100 100 100 100 100 H-PP 20 50 50 20 50 20 50 DVB 3 3 DCP 2 2 SP1045 5 5 stannous chloride 2 2 SiH 7 7 catalyst 7 7 OIL 100 100 100 100 Physical properties Hardness 93 64 64 96 56 95 64 TS (MPa) 10 8 11 10 12 14 Eb (%) 180 600 240 240 500 210 530 CS (%)-40 ° C 40 30 28 20 25 25 19 CS (% ) 70 ℃ 30 35 18 21 18 12 CS (%) 100 ℃ 40 47 47 28 23 22 19 Oil resistance (%) 35 24 17 15 15 12 10 Moldability test ○ ○ ○ ○ △ △ △ Low temperature impact resistance × × × × × × × Long-term reliability × × × × × × Light discoloration resistance ○ ○ × × ○ ○

Table 4 Comparative Example 7 8 9 10 11 12 Composition (parts by weight) EPDM 100 100 100 100 100 100 100 H-PP 20 50 20 20 50 50 50 SiH 7 28 SiH 7 28 SiH 7 28 catalyst 7 7 7 7 7 7 SEBS 5 5 5 PP-SEBS 5 5 5 OIL 100 100 100 100 Physical properties Hardness 93 64 64 96 65 94 63 TS (MPa) 12 14 18 15 13 13 11 Eb (%) 230 420 420 210 400 240 450 450 CS (%) -40 ° C 27 30 29 28 30 28 CS (%) 70 ° C 28 27 24 24 23 28 27 CS (%) 100 ° C 32 34 31 31 32 34 34 Oil resistance (%) 15 14 13 11 11 12 10 Formability test ○ ○ ○ ○ ○ ○ Low temperature impact resistance ○ ○ ○ ○ ○ ○ Long-term reliability × × × × × × Light discoloration resistance ○ ○ ○ ○ ○ ○

[0031]

INDUSTRIAL APPLICABILITY According to the present invention, a thermoplastic elastomer composition having stable low creep properties and low temperature impact resistance can be obtained. That is, while the elastomer composition is thermoplastic, it is excellent in flexibility, heat-resistant creep performance, low-temperature impact resistance, mechanical strength, and stably exhibits rubber elasticity equal to or higher than vulcanized rubber over a wide temperature range for a long period of time. In addition, because it has good oil resistance and free toning,
Suitable for use in automobile parts, home appliance parts, various wire coatings (insulation, sheath) and various industrial parts for which improvements in rubber elasticity, mechanical strength and molding speed, molding yield, degree of freedom in toning, etc. are desired. You can

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Claims (9)

[Claims] 1. A crystalline olefin resin (b) in an amount of 5 to 300 parts by weight per 100 parts by weight of an ethylene-α-olefin-non-conjugated diene copolymer rubber (a), and SiH in the molecule.
Organosiloxane cross-linking agent (c) having a group of 0.5 to 3
0 parts by weight, 0.001 to 2 parts by weight of a Group 8 transition metal-based hydrosilylation catalyst (d), and a compatibilizing agent (e) of 0.
In a thermoplastic elastomer obtained by mixing 5 to 20 parts by weight and dynamically heat-treating, a compound having a structure represented by the following structure is used as an organosiloxane cross-linking agent (c) having a SiH group in the molecule. A thermoplastic elastomer characterized by the following. (1) m is an integer of 5 or more and 400 or less (2) R _{1 to} R ₇ are hydrogen, an alkyl group, an alkoxy group,
Aryl or aryloxy group 2. A crystalline olefin resin (b) in an amount of 5 to 300 parts by weight, and SiH in the molecule, based on 100 parts by weight of an ethylene-α-olefin-non-conjugated diene copolymer rubber (a).
Organosiloxane cross-linking agent (c) having a group of 0.5 to 3
0 parts by weight, Group 8 transition metal hydrosilylation catalyst (d) 0.001 to 2 parts by weight, compatibilizer (e) 0.5 to
20 parts by weight and 30 to 3 of paraffin oil (f)
The thermoplastic elastomer according to claim 1, containing 100 parts by weight. 3. An organosiloxane crosslinking agent (c) having a SiH group in the molecule or a Group 8 transition metal hydrosilylation catalyst (d) is dissolved in at least one selected from liquid components and solid components. Or it is carried, The thermoplastic elastomer of Claim 1 or 2 characterized by the above-mentioned. 4. The compatibilizing agent (e) is the following compatibilizing agent (e-
1), one or more selected from (e-2),
The thermoplastic elastomer according to 2 or 3. (E-1) Hydrogenated block obtained by hydrogenating an end block A mainly composed of at least two vinyl aromatic compounds and an intermediate polymer block copolymer mainly composed of at least one conjugated diene compound Copolymer (e-2) Ethylene-α / olefin copolymer 5. The compatibilizer (e) is the following (e-3) (e-
4) One or more selected from (e-5).
Or the thermoplastic elastomer according to item 3. (E-3) Polyethylene resin having an epoxy group as an essential component, having a maleic anhydride group in the molecule, an ethylene copolymer, a styrene block copolymer and / or a hydrogenated product thereof, a styrene random copolymer And / or a compatibilizing agent (e-4) having a maleic anhydride group in the molecule, which is obtained by melting and reacting at least one selected from maleic anhydride-modified resins such as hydrogenated products thereof. Polypropylene is an essential component and is selected from polyethylene having an epoxy group, ethylene-based copolymer, styrene block copolymer and / or hydrogenated product thereof, styrene random copolymer and / or epoxy-modified resin such as hydrogenated product thereof. Is an essential component of a compatibilizing agent (e-5) polypropylene, characterized in that at least one of And a blend with at least one resin selected from polyethylene, ethylene-based copolymers, styrene block copolymers and / or hydrogenated products thereof, styrene random copolymers and / or hydrogenated products thereof. Compatibilizer formed by dynamic heat treatment in the presence of peroxide 6. The compatibilizers (e-3) and (e-4) have a ratio of epoxy modified resin and maleic anhydride modified resin,
Regarding (e-5), the ratio of polypropylene and one or more resin components selected from a specific group is 10:90.
-90: 10 wt% of the compatibilizer (e) is added in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the rubber component (a) + the resin component (b) in total. The thermoplastic elastomer according to claim 5. 7. The ethylene-α-olefin-non-conjugated diene copolymer (a) is an ethylene-propylene-ethylidene norbornene copolymer rubber, 1, 2, 3, 4,
5. The thermoplastic elastomer according to 5 or 6. 8. The ethylene-α-olefin-non-conjugated diene copolymer (a) has an ethylene / propylene weight ratio of 50 /.
An ethylene-propylene-ethylidene norbornene copolymer rubber having an iodine value of 50 to 90/10 and a Mooney viscosity ML1 + 4 (125 ° C.) of the rubber itself of 10 or more. The thermoplastic elastomer according to 4, 5, or 6. 9. The crystalline olefin resin (b) is MFR.
(ASTM-D-1238L condition, 230 ° C.) 0.1-50 g / 10 min polypropylene or its copolymer, the heat according to claim 1, 2, 3, 4, 5, 6, 7 or 8. Plastic elastomer.