JPS636101B2 - - Google Patents

Description

[Detailed description of the invention]

[] Background of the Invention Blends of olefin resins and similar elastomers have become widely used in recent years. The purpose can be broadly divided into two. One of them is aimed at improving the low-temperature impact properties of olefinic resins, such as polypropylene resins, and the other is aimed at imparting flexibility to olefinic resins. In the former case, it is desirable not to change the properties (especially stiffness) of the olefin resin other than low-temperature impact as much as possible, and conventionally, the amount of olefin elastomer blended with the olefin resin has generally been 5 to 5.
The amount is usually 20% by weight, and at most it is about 30% by weight. Also, in the case of the latter, which is aimed at flexibility,
Naturally, the blending amount of olefin elastomer to olefin resin is larger than in the former case,
It is widely practiced up to an upper limit of 80% by weight.
These are usually called "olefin thermoplastic elastomers.""Olefin-based thermoplastic elastomer" is a product obtained by melt-kneading an olefin-based resin and an olefin-based elastomer, and in some cases, partially crosslinking the rubber portion during melt-kneading, and is disclosed in Japanese Patent Application Laid-Open No. 49-53938. As seen in Japanese Patent Publication No. 53-34210, studies have focused on ethylene-propylene elastomer/polypropylene, taking advantage of its characteristics of being relatively inexpensive and having good flexibility, heat deformation resistance, and weather resistance. It has started to attract attention in fields such as automobiles, home appliance parts, footwear, and electric wires. However, in order to obtain good flexibility, olefinic elastomers (e.g. ethylene-
It is necessary to incorporate propylene binary copolymer elastomer or ethylene-propylene-nonconjugated diene terpolymer elastomer (hereinafter collectively referred to as EPR) at a fairly high concentration of 60% or more by weight of the total composition. Therefore, injection molded products have the disadvantage that the product appearance (flow marks, weld marks, gloss) is extremely poor. The present inventors have already proposed two techniques using specific olefin resins to solve this problem. (Patent Application No. 54-32954, No. 54-116036
(Specification) The present invention provides yet another proposal. [] Summary of the Invention The present invention aims to provide a solution to the above-mentioned drawbacks, and attempts to achieve this purpose by using a specific propylene copolymer as a resin component to be blended with an olefinic elastomer. That is. Therefore, the thermoplastic elastomer composition of the present invention contains the following components A1 to 80% by weight and components B99 to 20% by weight.
% by weight. Component A Copolymer elastomer consisting of ethylene, α-monoolefin, and optionally a non-conjugated diene Component B Perform the following step (1) and each step (1) to (3) at least once. Ethylene content 10-30% by weight, characterized by being produced by
Propylene-ethylene copolymer resin (1) A step of polymerizing propylene alone or a propylene/ethylene mixture with an ethylene content of 2% by weight or less to form a polymer in an amount corresponding to 0.1 to 30% by weight of the total polymer amount. . (2) Propylene with ethylene content of 2.5 to 15% by weight/
Polymerize the ethylene mixture to reduce the total amount of polymer to 10
Forming an amount of polymer corresponding to ~80% by weight. (3) Polymerize a propylene/ethylene mixture with an ethylene content of 30 to 95% by weight to
A step of forming a polymer in an amount corresponding to 50% by weight. In the present invention, a "composition consisting of component A and component B" refers to a composition in which component A and/or component B is partially crosslinked during mechanical melt-kneading, as well as a mechanically melt-kneaded product of both components. It should be understood as a term indicating that in addition to the essential components mentioned herein, non-essential auxiliary components may also be included. Effects In thermoplastic elastomer compositions based on olefin elastomer/propylene polymer, by using propylene-ethylene copolymer resin (component B) obtained in a specific process as the propylene polymer, conventional propylene polymer ( Good flexibility can be obtained at lower rubber concentrations compared to those using homopolymers, block copolymers with ethylene, and random ethylene copolymers). This has made it possible to significantly improve injection moldability and the appearance of injection molded products, which were the objectives of the present invention. Furthermore, even at the same elastomer concentration, the thermoplastic elastomer composition of the present invention not only has significantly superior flexibility in terms of appearance of injection molded products compared to those using conventional propylene polymers, but also has non-crosslinked The heat deformation resistance is improved, and both non-crosslinked and partially crosslinked types have the same flexibility and excellent oil resistance and mechanical strength and elongation properties. In addition, the earlier patent application No. 54-32954 or the patent application No.
It is a thermoplastic elastomer composition with a very well-balanced quality, having the same flexibility and significantly superior low-temperature impact strength compared to the thermoplastic elastomer composition obtained in the invention of No. 54-116032. [] Detailed Description of the Invention The thermoplastic elastomer composition of the present invention consists of component A, which is a soft segment, and component B, which is a hard segment. (1) Component A Component A as a soft segment is an ethylene-α-monoolefin binary copolymer elastomer or an ethylene-α-monoolefin-nonconjugated diene terpolymer elastomer.
A mixture of both can also be used. In the case of the ethylene-α-monoolefin binary copolymer elastomer, the ethylene content is preferably 20 to 90% by weight, preferably 40 to 85% by weight. In the case of an ethylene-α-monoolefin-nonconjugated diene terpolymer elastomer, the above binary composition ratio is maintained and the nonconjugated diene content is 0 to 15% by weight, preferably 1 to 10% by weight.
The one is good. As these elastomers, those having a Mooney viscosity (M _L1+4 100°C) of 20 to 300 are suitable. As the α-monoolefin of these elastomers, one or more of those having 3 to 12 carbon atoms can be used. Among these, propylene is the most common. Examples of non-conjugated dienes include linear dienes such as 1,4-pentadiene, 1,4-hexadiene, and 1,5-hexadiene, dicyclopentadiene, methylene norbornene, ethylidene norbornene, cyclooctadiene, methyltetrahydroindene, etc. One or more types of cyclic polyenes are used. Such elastomers can be appropriately selected from those produced by known general methods and used as they are. (2) Component B Component B as a hard segment is a special propylene-ethylene copolymer resin manufactured through the following steps. (1) Outline of the process Example from step (1), and steps (1) to (3)
It is necessary to perform each of them at least once, and it is normal to perform each of them once. However, it is also possible to carry out a plurality of times, and in particular, step (1) and step (2) can also be carried out two or more times. Furthermore, it is industrially advantageous to carry out steps (1) to (3) in this order. However, if it is carried out from step (1), it can be done in a different order, e.g.
It may be carried out in the order of (1)-(3)-(2). (2) Step (1) In step (1), propylene alone or a propylene/ethylene mixture with an ethylene content of 2% by weight or less, preferably 0.5% by weight or less is supplied to a polymerization system having a catalyst described below, and the total polymerization is carried out. amount of coalescence
An amount of polymer corresponding to 0.1 to 30% by weight, preferably 2 to 10% by weight is formed. If the ethylene content in the propylene/ethylene mixture exceeds the above value in step (1), not only will the bulk density of the final copolymer decrease, but the amount of low-crystalline polymer by-product will increase significantly, and component B
Unfavorable for manufacturing. In addition, if the polymer formation ratio is less than the above range, propylene/
A similar phenomenon occurs when the ethylene content in the ethylene mixture is too high. On the other hand, if the polymer formation ratio exceeds the above range, the thermoplastic elastomer composition obtained using this composition will contain the same amount of component A as that using component B within the range of the present invention, and will lose its flexibility. . The polymerization temperature in step (1) is usually about 0 to 80°C, preferably about 30 to 70°C. Polymerization pressure is 1~
It is about 30Kg/cm ² G. Further, it is preferable to use hydrogen or the like as a molecular weight regulator. The use of a molecular weight modifier provides good results in terms of moldability of the final thermoplastic elastomer composition. (3) Step (2) Step (2) includes an ethylene content of 2.5 to 15% by weight,
Preferably 3.5-10% by weight of the propylene/ethylene mixture is fed into the polymerization system to provide 10-80% by weight of the total polymer weight, preferably 40-75% by weight.
of polymer in an amount corresponding to . If the ethylene content in the propylene/ethylene mixture exceeds the amount, the formation of a low-crystalline polymer will significantly increase, and the viscosity of the polymer will also increase rapidly, making it difficult to implement on an industrial scale. On the other hand, if the ethylene content is less than the above range, there are problems with the low-temperature impact strength and flexibility of the thermoplastic elastomer composition using the polymer. Furthermore, if the polymer formation ratio is less than the above range, the thermoplastic elastomer composition obtained using the polymer will have a poor quality balance in flexibility, oil resistance, mechanical strength, etc.; on the other hand, if it exceeds the above range, The low-temperature impact strength and heat deformation resistance of the composition deteriorate. Polymerization temperature is usually 0~80℃, preferably 50~70℃
It is ℃. The polymerization pressure may be approximately the same as in step (1). Step (2) is also preferably carried out in the presence of a molecular weight regulator such as hydrogen. (4) Step (3) Step (3) involves feeding a propylene/ethylene mixture with an ethylene content of 30 to 95%, preferably 40 to 90% by weight, into the polymerization system to reduce the total amount of polymer from 10 to 90% by weight.
It consists in forming an amount of polymer corresponding to 50% by weight, preferably 20-40% by weight. If the ethylene content in the propylene/ethylene mixture exceeds the content, the appearance of the injection molded product of the thermoplastic elastomer composition obtained using the polymer deteriorates. On the other hand, if the ethylene content is less than the above range, the formation of a low-crystalline polymer will significantly increase, causing problems in the low-temperature impact strength of the thermoplastic elastomer composition obtained using the polymer. If the polymer production ratio in step (3) is less than the above range, the low-temperature impact strength of the composition will be poor, while if it exceeds the above range, the viscosity will increase significantly, causing problems in production. Polymerization temperature is usually 0~80℃, preferably 50~
The temperature is 70℃. The polymerization pressure may be the same as in step (1) or (2). In step (3), a molecular weight regulator may or may not be used depending on the purpose. The ethylene content of component B, which is the final polymer obtained through steps (1) to (3), must be in the range of 10 to 30% by weight. If the ethylene content of component B is less than 10% by weight, the resulting thermoplastic elastomer composition will have a poor balance of qualities such as flexibility, oil resistance, mechanical strength, and low-temperature impact strength; on the other hand, if it exceeds 30% by weight, , the increase in viscosity during the production of component B is a significant production problem. (5) Polymerization method and catalyst The copolymer resin of component B used in the present invention can be produced by a batch method, a continuous method, or a semi-continuous method. It is also possible to use heptane or other inert hydrocarbons, the monomer itself (propylene, ethylene) used as a medium, or to carry out the process in a gaseous monomer without using a medium. . All conventional stereoregular catalysts are used as catalysts. Typically, it is a composite catalyst of a titanium trichloride compound or a supported titanium catalyst component and a haloalkylaluminium compound having the general formula AlRnX _3-o . (3) Production of thermoplastic elastomer composition using component A and component B (1) Composition The proportion of component A and component B in the composition of the present invention is 1 to 80% by weight of component A and 99 to 99% by weight of component B.
It is 20% by weight. The preferred range of this ratio is determined by the desired physical properties of the product composition. If component A is less than the above range, flexibility and low-temperature impact strength will be a problem, while if component A is too large, moldability will be a problem. The thermoplastic elastomer composition of the present invention includes:
Weight ratio A/B = 1/99~60/40, especially 20/80~
In the 60/40 range, compared to those using conventional propylene polymers (homopolymer, ethylene block copolymer, ethylene random copolymer, etc.), partially crosslinked systems are particularly effective in improving the appearance, oil resistance, and freeness of molded products. The crosslinked system is further characterized by excellent heat deformation resistance, and the thermoplastic elastomer composition obtained in the invention of the earlier patent application No. 54-32954 or No. 54-116036 (one component is the invention) It has the same flexibility as Component A (a copolymer resin whose other components are propylene and C ₅ to C ₁₂ α-olefins) and has significantly superior low-temperature impact strength. has. Moreover, in the range of A/B=60/40 to 80/20, both non-crosslinked and partially crosslinked systems are characterized by excellent flexibility and mechanical strength. (2) Composite The present invention can be obtained by compounding component A and component B. In this case, the plurality of means is basically mechanical melt-kneading, as in the case of manufacturing a normal resin composition, but a crosslinking agent is present during melt-kneading, and either one or B of components A and B is mixed. Partial crosslinking can also occur between both or both. Mechanical melt kneading methods include single screw extruder,
General melt kneading machines such as a twin screw extruder, Banbury mixer, and various kneaders can be used. As the crosslinking agent to be added during melt-kneading to obtain a partially crosslinked product, aromatic or aliphatic peroxides or azo compounds are suitable. These may be used alone or in combination. Further, sulfur may be used in combination. Specific crosslinking agents include 2,5-dimethyl-2,5-(benzoylperoxy)hexane, t-butylperoxyperbenzoate, dicumyl peroxide, and 2,5-dimethyl-2,5-di(benzoylperoxy)hexane. t
-butylperoxy)hexane, t-butylcumyl peroxide, diisopropylbenzohydroperoxide, 1,3 bis-t
-butylperoxyisopropylbenzene, etc. The gel fraction of partially crosslinked materials is generally in the range of 20 to 95% by weight as insoluble matter when immersed in cyclohexane at 23°C. During crosslinking during mechanical melt-kneading, in order to make the crosslinking uniform and control the crosslinking reaction,
A crosslinking reaction retarder can also be used in combination, if necessary. The crosslinking reaction retarders used include hydroquinone, 2,6-di(t-butyl)-P-cresol, t-butylcatechol, 4,4'-butylidenebis(3-methyl-
6-t-butylphenol), 2,2'-methylenebis(4-methyl-6-t-butylphenol), 4,4'-thiobis(6-t-butyl-3-methylphenol), mercaptobenzothiazole, Dibenzothiazole disulfide, 2,2,4-trimethyl-1,2
-dihydroquinone polymer, phenyl-β-
There are organic peroxide crosslinking scorch inhibitors such as naphthylamine, N.N'-di-β-naphthyl-P-phenylenediamine, and N-nitrosodiphenylamine. The composition of the present invention blends commonly used fillers such as carbon and white fillers, paraffin, naphthenic process oil, plasticizers such as dioctyl phthalate, and pigments, as is done for ordinary resin compositions. It can be used as Further, additives such as a heat stabilizer, an antioxidant, and an ultraviolet absorber can be added as necessary. Other third component polymers may be used to the extent that the properties of the thermoplastic elastomer composition are not impaired, such as polar group-introduced polyolefins (e.g., ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, maleic anhydride grafted polypropylene, etc.). ), polyamide resin,
Polyester resins, thermoplastic styrene-butadiene copolymers, etc. can also be added. The composition of the present invention can be molded using a commonly used thermoplastic resin molding machine, and thermoplastic resin molding methods such as injection molding, extrusion molding, blow molding, and calendar molding can be applied. . Particularly, those having A/B=1/99 to 60/40 are suitable for injection molding. The products obtained by each of the above molding methods are thermoplastic elastomer molded products with an excellent quality balance in flexibility, heat deformation resistance, molded product appearance, oil resistance, mechanical strength properties, low-temperature impact strength, etc. The thermoplastic elastomer composition of the present invention is used in various electric wire coatings (insulations, sheaths), household appliance parts, automobile parts, and other industrial parts. Specific applications include various gaskets, flexible tubes, hose coverings, weather stripping, flexible bumpers, side bumpers, moldings, filler panels, lamp housings, wire cable coverings, and air take-in hoses. In particular, a control cable coated with the thermoplastic elastomer composition of the present invention includes a towable outer tube formed by spirally winding at least one metal wire (flat steel wire), and a control cable coated with the thermoplastic elastomer composition of the present invention. It has a basic structure consisting of a towable inner cable made of a single metal wire or several twisted metal wires, and the inner cable rotates within the outer tube or acts in the axial direction, and also rotates and acts in the axial direction. It has the function of simultaneously operating and remotely controlling passive devices, and is used to operate transmissions, brakes, clutches, speedometers, etc. of automobiles, motorcycles, bicycles, etc.).
It has excellent flexibility, heat deformation resistance, cold resistance, mechanical strength (wear resistance), and oil resistance. (4) Experimental Examples The following examples and comparative examples specifically illustrate the present invention. () Test method During the following experiment, the test method used to indicate the physical properties of each component and evaluate the resulting composition is as follows. (1) Melt index (230℃) ASTM-D-1238 [g/10min] (2) Mooney viscosity (M _L1+4 100℃) JIS-K-6300 [-] (3) Gel fraction cyclohexane immersion Insoluble content at 23°C/48 hours [wt%] (4) Flexural modulus JIS-K-7203 [Kg/cm ² ] (5) Deformation rate under heat and pressure A load was applied to the sample in heated silicone oil, and A sample (1cm x 1cm x 2mm
Attach a thick press sheet) and heat to 130℃.
After being left for 1 hour at ℃ under a load of 3 kg, the load was removed and the thickness deformation rate was obtained after 10 minutes. [%] (6) Tensile strength JIS-K-6301 test piece No. 3 [Kg/cm ² ] (Sample = 2 mm thick injection molded sheet) (7) Tensile elongation JIS-K-6301 test piece No. 3 Shape [%] (Sample = 2 mm thick injection molded sheet) (8) IZOD impact strength JIS-K-7110 [Kg・cm/cm] Notched measurement temperature -40℃ (9) Immersion test (mass change rate) 5cm x 2cm x 2mm thick press sheet
Obtained from the mass change rate when immersed in JIS-1 oil at 70°C for 72 hours. [%] (10) Appearance of injection molded products Injection molding machine and molding conditions Model 16oz in-line screw type Conditions Injection pressure 500-1000Kg/cm ² Injection temperature 200-230℃ Mold temperature 40℃ Regarding the appearance, Visual evaluation was performed from three points: flow mark, weld mark, and gloss. Evaluation criteria 〇 = Good △ = Slightly poor × = Poor [] Supply sample The contents of each sample are as follows. (1) EP-1 has Mooney viscosity (M _L1+4 , 100
EPDM (ethylene-propylene-nonconjugated diene elastomer) with a propylene content of 25% by weight and a content of 15 in terms of iodine value using ethylidene norbornene as the third component (diene compound). It is. (2) EP-2 has Mooney viscosity (M _L1+4 , 100
℃) is 83, the propylene content is 43% by weight, ethylidene norbornene is used as the third component (diene compound), and the content is 26 in terms of iodine value. (3) PP-1 is a propylene-ethylene copolymer (component B in the present invention) produced as follows, with an ethylene content of 15.5% by weight and a melt flow rate (230°C) of 1.2 g/
It's 10 minutes. After sufficiently replacing the interior of the polymerization reactor with an internal volume of 150 mm with a stirring blade, the n
- 50 g of heptane, 10 g of titanium trichloride, and 50 g of diethylaluminium chloride were added.
At a temperature of 65℃, propylene was introduced at 8.5 kg/hour for 30 minutes, and then 8.5 kg/hour of propylene was introduced.
Ethylene was introduced at a rate of 400 g/hour (mixture containing 4.5% by weight of ethylene) and copolymerization was carried out for 3 hours. During this period, the hydrogen concentration in the gas phase was 4.5
Hydrogen was supplied so as to be % by volume. After purging the system internal pressure to normal pressure, the temperature is 60℃.
1.07Kg/hour of propylene and ethylene at ℃
Introduced at 2.5Kg/hour (ethylene content 70% by weight)
(mixture)) Copolymerization was carried out for 1 hour and 50 minutes. The obtained copolymerization slurry was discharged into a catalyst decomposition tank containing n-heptane containing n-butanol to decompose the catalyst. The polymer was removed by centrifugation as a solvent-containing cake which was treated at 100° C. with pure water containing a non-ionic emulsifier and steam stripped to remove the solvent.
After that, the polymer is removed by centrifugation and heated and dried under vacuum to form a product copolymer of approx.
Got 20Kg. The ethylene content and polymerization ratio of the parts obtained in each step of the obtained copolymer were as follows.

[Table] To 100 parts by weight of the copolymer thus obtained, 0.1 part by weight of 2,6-di-tert-butyl-4-methylphenol (antioxidant), tetrakis [methylene-3-(3,5- Di-tert-butyl-4-hydroxyphenyl) propionate] methane (antioxidant) 0.05 parts by weight,
0.05 parts by weight of calcium stearate (neutralizer) was blended and melted and kneaded using an extruder with a screw diameter of 50 mm to form strands of 240 mm.
It was extruded at ℃ and cooled in water. The strands were then cut to obtain pellets with a diameter of 2 to 3 mm. (4) PP-2 is an isotactic polypropylene homopolymer with a melt flow rate of 1.2 g/10 minutes (manufactured by Mitsubishi Yuka Co., Ltd.,
Mitsubishi Noblen MH6). (5) PP-3 is a propylene-ethylene block copolymer with an ethylene content of 11% by weight and a melt flow rate of 1.8 g/10 min (manufactured by Mitsubishi Yuka Co., Ltd., Mitsubishi Noblen Co., Ltd.).
BC8). (6) PP-4 is a propylene-ethylene random copolymer with an ethylene content of 5.5
weight%, melt flow rate 5 g/10 min (manufactured by Mitsubishi Yuka Co., Ltd., Mitsubishi Noblen).
FU4). (7) PP-5 is a propylene-hexene-1 copolymer produced as follows, with a hexene-1 content of 11% by weight and a melt flow rate of 1.2 g/10 minutes. After sufficiently replacing the interior of the stirred polymerization reactor with an internal volume of 200 liters with propylene, the n-
45 liters of heptane, 6.5 g of titanium trichloride (TUS catalyst manufactured by Marubeni/Solvay Chemical),
32.5 g of diethyl aluminum chloride was added. Temperature: 50℃, propylene pressure: 2.0
Kg/cm ² G was maintained for 20 minutes to carry out homopolymerization of propylene. Then heat the greenhouse to 60℃
Propylene and hexene-1 were fed at a rate of 5.6 kg/hour and 6.6 liters/hour, respectively, over a period of 41 hours. Next, the supply of hexene-1 was stopped and only propylene was supplied.
It was fed over 1.5 hours at a rate of 5.6Kg/hour. During this time, hydrogen was continuously supplied so that the hydrogen concentration in the gas phase of the reactor was 1.6% by volume. After copolymerization, residual gas was removed, the copolymer slurry was transferred to another tank, and 75 liters of n-heptane and n-heptane were added to clean the inside of the polymerization vessel.
2 liters of butanol and 15 g of potassium hydroxide were added, and the mixture was stirred at 65° C. for 2 hours (decatalyzed and neutralized). The copolymer was removed as a solvent-containing cake by centrifugation, which was treated with 100 liters of pure water containing 13 g of nonionic emulsifier at 100 DEG C. and steam stripped to remove the solvent. after that,
The copolymer was taken out by centrifugation and vacuum dried to obtain a product copolymer. (8) The crosslinking agent (organic peroxide) is Percadox 14/40 (1,3-bis-(t-butylperoxyisopropyl) manufactured by Kayaku Nury Co., Ltd.
(40% benzene diluted product). (9) The crosslinking reaction retarder is Noxela DM (dibenzothiazole disulfide) manufactured by Ouchi Shinko Kagaku Co., Ltd. () Manufacture of Composition Using a 1.0 liter pressure kneader for rubber, the above sample was melt-kneaded at a set temperature of 170° C. for 10 minutes to prepare a sample. In addition, for partially crosslinked products, after melt-kneading component A and component B for about 3 minutes, a crosslinking agent and a crosslinking reaction retarder are added, and after addition,
A sample was obtained by melt-kneading for 7 minutes and crosslinking. However, for Examples 6 and 7,
Since component B is blended in the same amount or more as component A, in order to prevent component B from deteriorating due to the addition of a crosslinking agent (organic peroxide), first add 60 parts by weight of component A and 40 parts by weight of component B as described above. After preparing the crosslinked composition, a required amount of component B was further added to produce a predetermined composition. () Composition and physical properties (1) Using a conventional propylene polymer, the following thermoplastic elastomer composition was manufactured by the method described above. Comparative Example 1 (Non-crosslinked system) A thermoplastic elastomer composition obtained using 60 parts by weight of EP-1 as component A and 40 parts by weight of PP-2 as component B had a flexural modulus of 1800 kg/cm ² . Comparative Example 2 (Partially crosslinked system) 65 parts by weight of EP-2 as component A and 35 parts by weight of PP-3 as component B. In addition, 1.25 parts by weight of the above-mentioned crosslinking agent and 0.05 parts by weight of the above-mentioned crosslinking reaction retarder were used. The flexural modulus of the elastomer composition is
It was 700Kg/ ^cm2 . The gel fraction of this product was 82% by weight. On the other hand, in the thermoplastic elastomer composition of the present invention produced by a similar method, we searched for a composition that would provide the same flexibility as each of these compositions, and found the following composition. Example 1 (non-crosslinked system) EP-1 as component A 20 parts by weight PP-1 as component B 80 Example 2 (partially crosslinked system) EP-2 as component A 50 parts by weight PP-1 as component B 50 In addition, the same crosslinking agent as used in Comparative Example 2
1.25 parts by weight and 0.05 parts by weight of the same crosslinking reaction retarder were used. The gel fraction of the resulting composition was 81% by weight. From the above results, compared to conventional thermoplastic elastomer compositions using propylene polymers, the thermoplastic elastomer composition of the present invention requires a significantly lower blending ratio of rubber to provide the same flexibility. It turned out that. Table 1 shows the appearance of injection molded products made of these compositions. In the table, the evaluation was based on the following criteria.

【table】

[Table] (2) Using conventional propylene polymer, the above
The following thermoplastic elastomer composition was produced in the same manner as in (1). Comparative Example 3 (Partially crosslinked system) 60 parts by weight of EP-2 as component A 40 parts by weight of PP-3 as component B Other than the same crosslinking agent as used in Comparative Example 2
1.25 parts by weight and 0.05 parts by weight of the same crosslinking reaction retarder were used. The gel fraction of the resulting composition was 80% by weight. In contrast, the same EP-2 as component A
The thermoplastic elastomer composition of the present invention produced using the same blending ratio as above is as follows. Example 3 (Partially crosslinked system) 60 parts by weight of EP-2 as component A 40 parts by weight of PP-1 as component B Other than that, the same crosslinking agent as used in Comparative Example 2
1.25 parts by weight and 0.05 parts by weight of the same crosslinking reaction retarder were used. The gel fraction of the resulting composition was 81% by weight. The flexibility results of the thermoplastic elastomer compositions of Comparative Example 3 and Example 3 are shown in Table 2, and the flexibility of the thermoplastic elastomer compositions of the present invention is significantly superior at the same rubber content.

[Table] (3) Using conventional propylene polymer, the above
The following thermoplastic elastomer composition was produced in the same manner as in method (1). Comparative Example 4 (Non-crosslinked system) A thermoplastic elastomer composition obtained using 50 parts by weight of EP-1 as component A and 50 parts by weight of PP-3 as component B had a flexural modulus of 3200 kg/cm ² . Comparative Example 5 (Non-crosslinked system) A thermoplastic elastomer composition obtained using 65 parts by weight of EP-1 as component A and 35 parts by weight of PP-3 as component B had a flexural modulus of 1500 kg/cm ² . Comparative Example 6 (Partially crosslinked system) 70 parts by weight of EP-1 as component A 30 parts by weight of PP-2 as component B Other than the same crosslinking agent as used in Comparative Example 2
The flexural modulus of the thermoplastic elastomer composition obtained using 1.25 parts by weight and 0.05 parts by weight of the crosslinking reaction retarder was 1000 Kg/cm ² .
The gel fraction of this product was 78% by weight. Comparative Example 7 (Non-crosslinked system) The flexural modulus of a thermoplastic elastomer composition obtained using 70 parts by weight of EP-1 as component A and 30 parts by weight of PP-4 as component B was 550 kg/cm ² . In contrast, in the thermoplastic elastomer composition of the present invention, when we searched for a composition having a flexural modulus equivalent to each of these, we found the following composition.
As shown in Table 3, these compositions have heat resistance,
It has excellent tensile properties and oil resistance. Example 4 (non-crosslinked system) EP-1 as component A 10 parts by weight PP-1 as component B 90 Example 5 (non-crosslinked system) EP-1 as component A 40 parts by weight PP-1 as component B 60 Example 6 (Partially crosslinked system) EP-1 as component A 55 parts by weight PP-1 as component B 45 〃 In addition, the same crosslinking agent as used in Comparative Example 2
1.25 parts by weight and 0.05 parts by weight of the same crosslinking reaction retarder were used. The gel fraction of the resulting composition was 80% by weight. Example 7 (Non-crosslinked system) EP-1 as component A 65 parts by weight PP-1 as component B 35

[Table] (4) In the same manner as in (1) above, the earlier application
The following thermoplastic elastomer composition of No. 116036 was manufactured. Comparative Example 8 (Non-crosslinked system) The flexural modulus of a thermoplastic elastomer composition obtained using 20 parts by weight of EP-1 as component A and 80 parts by weight of PP-5 as component B was the same as that of Example 1. Ta. However, the low-temperature impact strength of the thermoplastic elastomer composition obtained in Comparative Example 8 was lower than the IZOD impact strength (notched, -40
℃) and 4.4 [Kg・cm/cm]. In contrast, the low-temperature impact strength of Example 1 was 25
[Kg·cm/cm] and was significantly superior to that of Comparative Example 8. (5) A thermoplastic elastomer composition of the present invention was manufactured using the following composition. Example 8 (Partially crosslinked system) 80 parts by weight of EP-2 as component A 20 parts by weight of PP-1 as component B Other than that, the same crosslinking agent as used in Comparative Example 2
1.25 parts by weight and 0.05 parts by weight of the same crosslinking reaction retarder were used. The gel fraction of the resulting composition was 71% by weight. This material had a bending modulus of 120 [Kg/cm ² ] and had excellent flexibility. A product having the same flexibility but manufactured using a conventional propylene polymer had the following composition. Comparative Example 9 (Partially crosslinked system) 90 parts by weight of EP-2 as component A 10 parts by weight of PP-1 as component B Other than that, the same crosslinking agent as used in Comparative Example 2
1.25 parts by weight and 0.05 parts by weight of the same crosslinking reaction retarder were used. The gel fraction of the resulting composition was 67% by weight. This product caused significant deformation, delamination, etc. during injection molding, and could not be used as a thermoplastic elastomer composition.

Claims (1)

[Scope of Claims] 1 The following components A1 to 80% by weight and components B99 to
A thermoplastic elastomer composition characterized in that it consists of 20% by weight. Component A Copolymer elastomer consisting of ethylene, α-monoolefin, and optionally a non-conjugated diene Component B Perform the following step (1) and each step (1) to (3) at least once. Ethylene content 10-30% by weight, characterized by being produced by
Propylene-ethylene copolymer (1) Polymerize propylene alone or a propylene/ethylene mixture with an ethylene content of 2% by weight or less,
A step of forming a polymer in an amount corresponding to 0.1 to 30% by weight of the total polymer amount. (2) Propylene with ethylene content of 2.5 to 15% by weight/
Polymerize the ethylene mixture to reduce the total amount of polymer to 10
Forming an amount of polymer corresponding to ~80% by weight. (3) Polymerize a propylene/ethylene mixture with an ethylene content of 30 to 95% by weight to
A step of forming a polymer in an amount corresponding to 50% by weight.