JPS6259139B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing thermoplastic elastomers. More specifically, the present invention relates to a partially crosslinked olefinic thermoplastic elastomer suitable for extrusion molding or injection molding of large, thick-walled products. When injection molding ordinary rubber, it is necessary to mix additives with the rubber, knead it, feed it into the mold, and then vulcanize it, which requires a special molding machine, takes a long cycle time, and complicates the process. There was a problem that. Similar problems exist in extrusion molding, which has become a bottleneck in the mass production of rubber products. Therefore, alternatives to rubber are being considered using materials that can be molded without vulcanization and have properties similar to rubber.
Among materials with such performance, soft plastics such as soft vinyl chloride resin, ethylene-vinyl acetate copolymer, and low-density polyethylene have the advantages of good moldability and high flexibility. On the other hand, its uses are severely limited due to drawbacks such as poor heat resistance, mechanical strength, and rebound resilience. Attempts have been made to improve heat resistance and mechanical strength by mixing soft plastics with plastics with high melting points, such as high-density polyethylene and polypropylene, but this results in loss of flexibility and the need for thick products. When molding, sink marks occur and a good product cannot be obtained. Therefore, recently, so-called thermoplastic elastomers have begun to attract attention as having performance intermediate between vulcanized rubber and soft plastics. Olefin thermoplastic elastomers are also already known, such as polyethylene-butyl rubber graft copolymers or ethylene-propylene-
Several products have been proposed whose main component is nonconjugated diene rubber. As one of the olefin-based thermoplastic elastomers, a composition consisting of polyolefin plastic and partially crosslinked rubber was also developed in 1973.
It is known from the publication No.-34210. According to additional tests conducted by the present inventors, the composition has excellent performance as a thermoplastic elastomer, but its fluidity is significantly inferior to that of general-purpose plastics, and when injection molding thick or large products. , it became clear that significant flow marks were produced and a product with good appearance could not be obtained. As a method for improving the fluidity of a composition comprising a polyolefin plastic and a partially crosslinked rubber, (a) a polyolefin plastic and/or a raw material rubber having a low molecular weight is usually used. (b) Reduce the degree of crosslinking of rubber. (c) Although measures such as increasing the blending ratio of polyolefin plastic can be considered, method (a) results in a decrease in the tensile properties of the composition. In the method (b), the heat resistance, tensile properties, and impact resilience of the composition deteriorate. Method (c) had drawbacks such as loss of flexibility of the composition and tendency to cause sink marks when made into thick-walled products. The purpose of the present invention is to improve heat resistance, tensile properties, weather resistance,
The object of the present invention is to provide a thermoplastic elastomer with good flexibility and rebound resilience. Another object of the present invention is to provide a thermoplastic elastomer that has good flow properties and can be easily molded into large, thick products without sink marks or flow marks by extrusion molding or injection molding. Still another object of the present invention is to
The thermoplastic elastomer disclosed in Publication No. 34210 has been improved to obtain a product with improved flowability and therefore good appearance without substantially impairing the heat resistance, tensile properties, flexibility and rebound properties of the thermoplastic elastomer. The object of the present invention is to provide a thermoplastic elastomer with a high temperature. That is, the first thermoplastic elastomer of the present invention contains (a) 50 to 90 parts by weight of peroxide crosslinked olefin copolymer rubber, (b) 50 to 10 parts by weight of peroxide crosslinked polyolefin resin (herein, (a)
+(b) is selected to be 100 parts by weight. ) If necessary, (c) up to 100 parts by weight of (c) peroxide non-crosslinked hydrocarbon-based rubbery material and/or (d) mineral oil-based softener, (e) organic peroxide (a), (b), ( c) 0.05 to 1% by weight based on the total amount of each component, and (f) crosslinking aid.
Obtained by dynamic heat treatment of (a), (b), (c) 0.07 to 2% by weight based on the total amount of each component and (g) 10 to 100 parts by weight of peroxide non-crosslinked polyolefin resin. The second thermoplastic elastomer of the present invention comprises (a) 50 to 90 parts by weight of peroxide crosslinked olefin copolymer rubber, and (b) 50 to 10 parts by weight of peroxide crosslinked polyolefin resin. (Here, (a) + (b) is
Select 100 parts by weight. ), if necessary (c)
up to 100 parts by weight of peroxide non-crosslinked hydrocarbon rubbery material and/or (d) mineral oil softener;
(e) 0.05 to 1% by weight of organic peroxide based on the total amount of each component (a), (b), (c), (f) crosslinking aid (a),
(b), (c) 0.07 to 2% by weight based on the total amount of each component
(g) a product obtained by dynamic heat treatment in the presence or absence of a peroxide non-crosslinked polyolefin resin, and (h) a polyolefin resin, and (a) and (b). It is a thermoplastic elastomer in which the total amount of component (g) and (h) is 10 to 100 parts by weight based on 100 parts by weight of component (). In the present invention, (a) peroxide crosslinked olefin-based copolymer rubber refers to an amorphous form mainly composed of olefin, such as ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene rubber, and ethylene-butadiene copolymer rubber. Rubber is an elastic copolymer of (e), which is crosslinked by mixing with organic peroxide and kneading under heating, resulting in decreased fluidity or no fluidity. Among these, ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene rubber (here,
Non-conjugated dienes include dicyclopentadiene, 1,
4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene, etc. ) in which the molar ratio of ethylene units to propylene units (ethylene/propylene) is preferably 50/50 to 85/15, more preferably 8
0-20 to 55/45. Among these, ethylene-propylene-nonconjugated diene copolymer rubber, particularly ethylene-propylene-ethylidene norbornene copolymer rubber, is preferred because it yields a thermoplastic elastomer with excellent heat resistance, tensile properties, and rebound resilience.
Mooney viscosity ^ML 1+4 (100℃) of copolymer rubber is
A Mooney viscosity of 10 to 120, particularly 40 to 80, is preferred; if the Mooney viscosity is less than 10, a composition with poor tensile properties will be obtained, while if it exceeds 120, the fluidity of the composition will be poor. do not have.
Also, the iodine value (degree of unsaturation) of the rubber is preferably 16.
Below, within this range, a thermoplastic elastomer with well-balanced fluidity and rubbery properties can be obtained. In the present invention, (b) peroxide crosslinked polyolefin resin is a polyolefin resin that is crosslinked by kneading with (e) organic peroxide under heating, resulting in a decrease in fluidity or becoming non-flowable, and includes high density polyethylene, low density polyethylene,
A copolymer of ethylene containing more than 85 mol% of ethylene units and an α-olefin having 3 to 10 carbon atoms; a copolymer of ethylene containing more than 85 mol% of ethylene units and a polar group such as vinyl acetate, acrylic ester, or methacrylic ester Preferred examples include polyethylene resins such as copolymers with monomers having olefinic double bonds, and among them, those having a melt index (190°C) of 0.01 to 200, particularly
0.1 to 100 polyethylene resin is preferred.
The polyolefin resin of component (b) is partially co-crosslinked with the olefin copolymer rubber of component (a) in a dynamic heat treatment process, thereby contributing to an increase in the strength of the thermoplastic elastomer of the present invention. . In order to achieve the blending effect of component (b), the weight ratio ((a)/(b)) of (b) peroxide crosslinked polyolefin resin to (a) peroxide crosslinked olefin copolymer rubber is 50/ 50 to 90~10, preferably 60/4
Blend so that the ratio is 0 to 90/10. From 90/10
If the amount of component (b) is small, the purpose of adding component (b) cannot be achieved, and if the amount of component (b) is more than 50/50, the fluidity of the thermoplastic elastomer will decrease, and the moldability of the thermoplastic elastomer of the present invention will be reduced. becomes worse. In the present invention, (c) a peroxide non-crosslinked hydrocarbon-based rubbery substance and/or (d) a mineral oil-based softener are added as necessary during the dynamic heat treatment.
Here, (c) peroxide non-crosslinked hydrocarbon rubber material includes, for example, polyisobutylene, butyl rubber, propylene-ethylene copolymer rubber containing 70 mol% or more of propylene, propylene-1-butene copolymer rubber, and atactic polypropylene. A hydrocarbon-based rubbery substance that does not crosslink or lose fluidity even when mixed with peroxide and kneaded under heat. Among these, polyisobutylene is most preferred in terms of performance and handling. In the present invention, crosslinking refers to a competitive reaction between a decomposition reaction and a crosslinking reaction that occur when a polymer is thermally reacted with (e) an organic peroxide, and as a result, the apparent molecular weight of the polymer increases as a result of a large number of crosslinking reactions occurring. Decomposition refers to a reaction phenomenon in which the apparent molecular weight of a polymer decreases as a result of many decomposition reactions. It is preferred that the Mooney viscosity of the hydrocarbon rubber material (c), particularly polyisobutylene, be 60 or less in order to improve the fluidity of the composition.
The amount of rubbery substance (c) is the above component (a) + component (b).
In the range of 0 to 40 parts by weight, preferably 5 to 20 parts by weight, per 100 parts by weight, if the amount exceeds the above range, the heat resistance and tensile properties of the thermoplastic elastomer will deteriorate, etc. This brings about the same drawbacks as when the degree of crosslinking of the copolymer rubber is too low. (d) Mineral oil-based softener in the present invention usually weakens the intermolecular force of rubber during roll processing, making processing easier, and assisting in the dispersion of carbon black, white carbon, etc. A high boiling point petroleum fraction used to reduce the hardness of sulfur rubber and increase its flexibility and elasticity.
They are classified into paraffin, naphthene, aromatic, etc. (d) in the present invention
The blending amount of the mineral oil softener is the above component (a) + component (b).
The proportion is from 0 to 80 parts by weight, preferably from 5 to 60 parts by weight, in particular from 10 to 40 parts by weight, per 100 parts by weight. If the amount of the softener exceeds the above range, the heat resistance of the thermoplastic elastomer will be lowered, or the softener will ooze out, causing unfavorable effects such as impairing the appearance. By blending such (c) peroxide non-crosslinked hydrocarbon rubbery substance and/or (d) mineral oil softener, the thermoplastic elastomer of the present invention has improved heat resistance, tensile properties, flexibility, and repulsion. Fluidity is improved without substantially impairing rubbery properties such as elasticity, and as a result, large, thick products with excellent appearance and no sink marks can be molded. The ratio of component (c) and/or (d) to component (a) + (b) is:
The amount is at most 100 parts by weight, preferably in the range of 10 to 50 parts by weight, particularly in the range of 20 to 40 parts by weight, based on 100 parts by weight of components (a)+(b). If the amount of components (c) and/or (d) exceeds 100 parts by weight, the physical properties such as heat resistance and tensile properties of the thermoplastic elastomer will be significantly reduced. Examples of the organic peroxide (e) of the present invention include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di-
(tert-butylperoxy)hexane, 2,5-
Dimethyl-2,5-di(tert-butylperoxy)hexyne-3,1,3-bis(tert-butylperoxyisopropyl)penzene, 1,1-bis(tert-butylperoxy)-3,3,5-trimethyl Cyclohexane, n-butyl-4,4-
Bis(tert-butylperoxy)valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate,
tert-butyl perbenzoate, tert-butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-
Butylcumyl peroxide and the like can be mentioned. Among these, 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 Preferred is n-butyl-4,4-bis(tert-butylperoxy)valerate, and most preferred is 1,3-bis(tert-butylperoxyisopropyl)benzene. The amount of organic peroxide blended is 0.05 to 1% by weight, preferably 0.05 to 1% by weight, based on the total amount of each component (a), (b), and (c).
It should be chosen to be in the range of 0.1 to 0.5% by weight. If the blending amount is less than 0.05% by weight, (a) and
As a result of the degree of crosslinking of component (b) being too low, the thermoplastic elastomer of the present invention has insufficient rubbery properties such as heat resistance, tensile properties, elastic recovery and rebound resilience, and strength; on the other hand, if it exceeds 1% by weight, As a result of the increased degree of crosslinking of components (a) and (b), the moldability of the thermoplastic elastomer decreases. In the present invention, (f) a crosslinking aid is blended together with (e) an organic peroxide during the dynamic heat treatment. (f) Specific examples of crosslinking aids include sulfur, p-quinonedioxime, p,p'-dibenzoylquinonedioxime, N-methyl-N,4-dinitrosoaniline,
Nitrobenzene, diphenylguanidine, trimethylolpropane-N,N'-m-phenylene dimaleimide, divinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, Mention may be made of allyl methacrylate, vinyl butyrate or vinyl stearate. By using such a crosslinking aid (f), a uniform and mild crosslinking reaction can be expected. In particular, in the present invention, it is most preferable to use divinylbenzene because it is easy to handle and a thermoplastic elastomer with well-balanced fluidity and physical properties can be obtained. That is, divinylbenzene is liquid at room temperature, can dissolve (e) organic peroxide, and has solubility in components (a) to (d) described above, as well as component (g) described later. (e) As a dispersion aid and diluent for organic peroxides, it improves the dispersibility of organic peroxides into each component, and therefore,
In particular, it works to bring uniform and mild crosslinking to components (a) and (b), and divinylbenzene itself becomes a radical and acts as a chain transfer agent and crosslinking agent, so by using divinylbenzene,
(e) A crosslinking effect greater than that achieved by using an organic peroxide alone can be expected. Therefore, the tensile properties and heat resistance of the thermoplastic elastomers of the present invention are improved.
In addition, (e) since the reactivity with organic peroxides is good, monomers are less likely to remain in the produced composition and cause odor. Note that divinylbenzene does not need to be a pure product, and may be a mixture with other hydrocarbon compounds. Like this (f)
The blending amount of the crosslinking aid is preferably in the range of 0.07 to 2% by weight, particularly 0.3 to 1% by weight, based on the total amount of each component (a), (b), and (c), and if it is blended in excess of 2% by weight, , (e) If the amount of organic peroxide is too large, the crosslinking reaction will progress and the fluidity of the composition will be poor; on the other hand, if the amount of (e) organic peroxide is too small, unreacted monomers will form in the composition. exists in
Excessive blending should be avoided since physical properties may change due to thermal history during processing and molding of the composition. The peroxide non-crosslinked polyolefin resin (g) of the present invention is a crystal such as polypropylene or a copolymer of propylene containing 85 mol% or more of propylene units and an α-olefin having 2 to 10 carbon atoms excluding propylene. polypropylene resin; crystalline polybutene resin such as poly 1-butene or a copolymer of 1-butene containing 85 mol% or more of 1-butene units and α-olefin having 2 to 10 carbon atoms excluding 1-butene; Resin; furthermore, poly4-methyl-1-pentene or 4-methyl-1-pentene containing 85 mol% or more of 4-methyl-1-pentene units.
Examples include crystalline poly-4-methyl-1-pentene resins such as copolymers of methyl-1-pentene and α-olefins having 2 to 10 carbon atoms excluding 4-methyl-1-pentene. Among them, polypropylene resins and polybutene resins are preferred, and the melt index (230°C) is 0.1.
Polypropylene resins having a molecular weight of from 100 to 100, particularly from 0.5 to 50, are preferred. The first thermoplastic elastomer of the present invention includes (a),
It is a product obtained by dynamically heat-treating components (b), (e), (f), and (g) in the presence of components (c) and (d) as necessary. At this time, component (g) is the same as component (a).
It is blended in an amount of 10 to 100 parts by weight, preferably 15 to 100 parts by weight, per 100 parts by weight of the total amount of component (b). 100
If the (g) resin part is more than the weight part, the thermoplastic elastomer will lose its rubbery properties, and if it is less than 10 parts by weight, the fluidity will decrease and the strength will also be low. The second thermoplastic elastomer of the present invention is (a)
(b), (e), (f) ingredients are mixed as necessary (c),
a product obtained by dynamic heat treatment of component (d) and optionally present component (g); and (h)
It is a thermoplastic elastomer obtained by further uniformly mixing it with a polyolefin resin. Here, (h) polyolefin resin refers to high-density polyethylene, low-density polyethylene, a copolymer of ethylene containing more than 85 mol% of ethylene units and α-olefin having 3 to 10 carbon atoms other than ethylene,
Or polyethylene-based copolymers such as ethylene containing more than 85 mol% of ethylene units and monomers containing polar groups such as vinyl acetate, acrylic esters, and methacrylic esters and having olefinic double bonds. Resin; crystalline polypropylene resin such as polypropylene or a copolymer of propylene containing 85 mol% or more of propylene units and α-olefin having 2 to 10 carbon atoms excluding propylene; poly 1-butene or 1-butene unit 1-butene containing 85 mol% or more of
- Crystalline polybutene resins such as copolymers with α-olefins having 2 to 10 carbon atoms excluding butene;
Furthermore, poly4-methyl-1-pentene or 4
-4-Methyl-1-pentene and 4-methyl-1 containing 85 mol% or more of methyl-1-pentene units
-Crystalline poly-4-methyl such as copolymer with α-olefin having 2 to 10 carbon atoms excluding pentene-
Examples include 1-pentene resins, among which polyethylene resins and polypropylene resins are preferred, especially melt index (measured at 190°C in the case of polyethylene resins).
For polypropylene resin, measure at 230℃. )
Polyethylene resins or polypropylene resins having a 0.1 to 100, particularly 0.5 to 50 are preferred. In the second thermoplastic elastomer of the present invention, the component (g) and the component (h) are complementary to each other and play a role in improving the fluidity and strength of the thermoplastic elastomer of the present invention. fulfill.
To achieve this effect, the total amount of component (g) and component (h) is
(a) Peroxide crosslinked olefin copolymer rubber
(b) The amount is 10 to 100 parts by weight, preferably 15 to 100 parts by weight, based on 100 parts by weight of the total amount of peroxide crosslinked polyolefin resin. If the resin part is more than 100 parts by weight, the thermoplastic elastomer of the present invention will not lose its rubbery properties, and if it is less than 10 parts by weight, the fluidity will decrease and the strength will also be low. At this time, component (g) may or may not be present in the second thermoplastic elastomer of the present invention. It goes without saying that the resins of component (g) and component (h) may be different. In the present invention, dynamic heat treatment refers to (e) melting and kneading the above-mentioned components including the organic peroxide. Kneading equipment includes open-type mixing rolls, closed-type Banbury mixers, extruders,
Conventionally known kneaders, continuous mixers, etc. can be used. Among these, it is preferable to use a closed type apparatus, and it is preferable to knead in an inert gas atmosphere such as nitrogen or carbon dioxide gas. The kneading is carried out at a temperature such that the half-life of the (e) organic peroxide used is less than 1 minute, usually 150 to 280°C, preferably 170 to 240°C, for 1 to 20 minutes, preferably 3
Or just do it for 10 minutes. In the present invention, the preferred method for mixing and kneading the above-mentioned components is (a) peroxide crosslinked olefin copolymer rubber, (b) peroxide crosslinked polyolefin resin, and if necessary, (c) peroxide crosslinked olefin copolymer rubber. A non-crosslinked rubbery substance and/or (d) a mineral oil-based softener and optionally (g) a peroxide non-crosslinked polyolefin resin are mixed in advance and, after uniform kneading, (e) an organic peroxide and (f) a non-crosslinked polyolefin resin; ) It is preferable to adopt a method in which a crosslinking aid is blended and kneaded under the above-mentioned predetermined conditions. Furthermore, when blending the product from the dynamic heat treatment step with (h) the polyolefin resin, that is, when obtaining the second thermoplastic elastomer, the shredded product and the pellet-like or powder-like product are combined. (h) The polyolefin resin may be mixed once using a V-type blender, tumbler blender, ribbon blender, Henschel mixer, etc., and then melt-kneaded using an extruder, mixing roll, kneader, Banbury mixer, etc. In the thermoplastic elastomer of the present invention, as long as the strength, moldability and rubber properties are not impaired,
Fillers such as calcium carbonate, calcium silicate, clay, kaolin, talc, silica, diatomaceous earth, mica powder, asbestos, alumina, barium sulfate, aluminum sulfate, calcium sulfate, basic magnesium carbonate, molybdenum disulfide, graphite, Glass fibers, glass bulbs, shirasu balloons, carbon fibers, etc. or coloring agents such as carbon black, titanium oxide, zinc white, red ultramarine, navy blue, azo pigments, nitroso pigments, lake pigments, phthalocyanine pigments, etc. can be blended. The present invention also uses known heat-resistant stabilizers such as phenol-based, sulfite-based, phenylalkane-based, phosphite-based or amine-based stabilizers, anti-aging agents, weather-resistant stabilizers, antistatic agents, lubricants such as metal soaps, waxes, etc. can be blended to the extent used in olefin plastics or olefin copolymer rubbers. These fillers,
Weathering stabilizers, heat stabilizers, anti-aging agents, coloring agents, etc. may be added at any stage of the process. (e) Trisethylamine, tributylamine,
Tertiary amines such as 2,4,6-tris(dimethylamino)phenol, and organic metals such as naphthenates and octoates of aluminum, cobalt, vanadium, copper, calcium, zirconium, manganese, magnesium, lead, mercury, etc. A carboxylic acid salt can also be used in combination in the process of dynamic heat treatment. The thermoplastic elastomer of the present invention can be molded using equipment commonly used for thermoplastics, and is suitable for extrusion molding, calendar molding and especially injection molding. The thermoplastic elastomer of the present invention also has heat resistance, because component (a) is partially crosslinked.
It has excellent rubber properties such as weather resistance, tensile properties, flexibility, and rebound resilience, and has good fluidity, so when it is made into large thick products, it has a good appearance without flow marks or sink marks. can get. The thermoplastic elastomer of the present invention can be used in automobile parts such as body panels, bumper parts, side shields and steering wheels, footwear such as shoe soles and sandals, electrical parts such as wire sheaths, connectors and cap plugs, and golf club grits. Examples include leisure items such as baseball bat grips, swimming pools, swimming fins, and underwater glasses, and miscellaneous items such as gaskets, waterproof cloth, garden hoses, and belts. The thermoplastic elastomer of the present invention is particularly suitable for use in large, thick-walled products such as bumper parts. Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples unless the gist thereof is exceeded. The moldability and basic physical properties of the thermoplastic elastomers in Examples were evaluated by the following methods. [Test method] (1) Injection moldability (A) Molding conditions Injection molding was performed using the following equipment and conditions. Molding machine: Dynamelter (manufactured by Meiki Seisakusho) Molding temperature: 200℃ Injection pressure: Primary pressure 1300Kg/cm ² Secondary pressure 700Kg/cm ² Injection pressure: Maximum molding speed: 90 seconds/1 cycle Gate: Direct gate (land) (Length 10mm, Width 10mm, Thickness 3mm) Molded products: 3 types of square plates (Length 300mm, Width 180mm, Thickness 3, 8, 15mm) (B) Appearance judgment criteria for molded products Flow Mark Rating: Judgment criteria 1: Significantly many flow marks 2: Significantly visible on the entire surface of the molded product 3: Slightly visible on the entire surface 4: Slightly visible only on the opposite side of the gate 5: No flow marks at all Sink marks: Judgment criteria ○: No sink marks at all △: Only seen on the opposite side of the gate
Measured in °. Rating: Criteria ○: Gloss is 25% or more △: Gloss is 10 to 25% ×: Gloss is 10% or less (2) Extrusion moldability (A) Molding conditions Tube with the following equipment and conditions was extruded. Molding machine: 40mmφ extruder (manufactured by Toshiba Machine) Molding temperature: 210℃ Die: Straight die (die/core = 12.5mm/10.0mm) Take-up speed: 10m/mm (B) Appearance criteria for molded products Tube surface The unevenness is evaluated in the following five stages. Rating: Judgment Criteria 5: Skin is extremely smooth and shiny 4: Skin is smooth but not shiny 3: Slightly rough skin 2: Significantly rough skin 1: Large wavy rough skin (3) Basic physical properties Injection molded using the method in (1) A test piece was cut from a square plate with a thickness of 3 mm obtained by the above method, and measured by the following method. Tensile properties: Measured according to JIS K-6301 method. Spring hardness: Measured using the JIS A type method described in JIS K-6301. Permanent elongation: Measured by the method of JIS K-6301. Heat-resistant temperature: Place the test piece in a constant temperature bath and adjust the temperature of the bath.
The temperature is expressed as the temperature at which a 0.8 mm diameter needle with a load of 49 g penetrates 0.1 mm into the sample when the temperature is raised at a rate of 20° C./min. Example 1 Ethylene content 70 mol%, Mooney viscosity ML ₁₊₄
(100℃) 70 ethylene-propylene copolymer rubber (hereinafter abbreviated as EPM), melt index (ASTM D-1238-65T, 190℃) 1.9, density 0.920 high-pressure polyethylene (hereinafter abbreviated as PE). ) 20 parts by weight, melt index (ASTM
D-1238-65T, 230℃) 13, 10 parts by weight of polypropylene (hereinafter abbreviated as PP) with a density of 0.91 g/cm ² , polyisobutylene (manufactured by Etsuso Corporation: trade name Vistanex MML-100, hereinafter abbreviated as PIB). 10 parts by weight and 30 parts by weight of naphthenic process oil (hereinafter abbreviated as oil) were kneaded for 5 minutes at 180°C in a nitrogen atmosphere using a Banbury mixer, passed through a roll, and made into pellets using a sheet cutter. process). Next, the pellets were mixed with a solution in which 0.3 parts by weight of 1,3-bis(tert-butylperoxyisopropyl)benzene (hereinafter referred to as peroxide A) was dissolved and dispersed in 0.5 parts by weight of divinylbenzene (hereinafter referred to as DVB). The solution was mixed using a tumble blender to uniformly adhere to the pellet surface. The pellets were then extruded using an extruder at 210°C under a nitrogen atmosphere (second step). Next, 100 parts by weight of the pellets obtained in the second step and 20 parts by weight of PP pellets were mixed in a tumbler blender and extruded at 210°C in an extruder to obtain the desired thermoplastic elastomer (third step). Using this thermoplastic elastomer, basic physical properties and moldability were evaluated by the methods described above. Example 2 Instead of PP used in the third step of Example 1,
The same procedure as in Example 1 was carried out except that 30 parts by weight of PE used in the first step of Example 1 was used. Example 3 Instead of PP used in the third step of Example 1,
The same procedure as in Example 1 was conducted except that 50 parts by weight of ethylene/vinyl acetate copolymer (hereinafter abbreviated as EVA) having a melt index (190° C.) of 15 and a vinyl acetate content of 14% by weight was used. Examples 4 to 6 In the first step of Example 1, the amount of PE added was
The procedures were carried out in the same manner as in Examples 1 to 3, except that the amount was 30 parts by weight and PP was not blended. Example 7 If the blending amount of PE is 10 parts by weight and the blending amount of PP is 20 parts by weight in the first step of Example 1, and the third step is not carried out, the pellets obtained in the second step are thermoplastic. Evaluation as an elastomer was conducted in the same manner as in Example 1. Example 8 Instead of the EPM used in the first step of Example 1, the molar ratio of ethylene units to propylene units (ethylene/propylene) was 65/35, the Mooney viscosity (ML ₁₊₄ , 100°C) was 70, and iodine was used. The same procedure as in Example 1 was carried out except that ethylene-propylene-ethylidenenorbornene copolymer rubber (abbreviated as EPDM) having a valence of 15 was used. Comparative Example 1 The same procedure as in Example 1 was conducted except that PP was not blended in the first step and the amount of PP blended in the third step was 5 parts by weight. Comparative Example 2 Evaluation of the thermoplastic elastomer obtained in the second step when the blending amount of PE in the first step of Example 1 was 20 parts by weight and the blending amount of PP was 5 parts by weight, and the third step was not performed. was carried out in the same manner as in Example 1. Comparative Example 3 Comparative Example 1 was carried out in the same manner as in Comparative Example 1, except that in the first step, the amounts of EPM, PE, and PP were changed to 30, 40, and 20 parts by weight, respectively. Comparative Example 4 Comparative Example 2 was carried out in the same manner as in Comparative Example 2, except that in the first step, the amounts of EPM, PE, and PP were changed to 30, 10, and 50 parts by weight, respectively. Comparative Examples 5 and 6 In the first step of Example 1, the amount of DVB blended was 0.
Or, the same procedure as in Example 1 was carried out except that the amount was 3.0 parts by weight. Comparative Examples 7 and 8 Example 1 except that the amount of peroxide A in the first step of Example 1 was 1.5 or 0.01 parts by weight, respectively.
I went in the same way. Table 1 shows the blending ratios of each example and comparative example, and Table 2 shows the evaluation results of basic physical properties and moldability.

【table】

【table】

Claims (1)

[Scope of Claims] 1 (a) 50 to 90 parts by weight of peroxide crosslinked olefin copolymer rubber, (b) 50 to 10 parts by weight of peroxide crosslinked polyolefin resin (where (a)
+ (b) selected to be 100 parts by weight), optionally up to 100 parts by weight of (c) peroxide non-crosslinked hydrocarbon-based rubbery material and/or (d) mineral oil-based softener; e) 0.05 to 1% by weight of organic peroxide based on the total amount of components (a), (b) and (c), (f) crosslinking agent (a),
A thermoplastic elastomer obtained by dynamically heat-treating (b) and (c) 0.07 to 2% by weight based on the total amount of each component and (g) 10 to 100 parts by weight of a peroxide non-crosslinked polyolefin resin. 2 (a) The peroxide crosslinked olefin copolymer rubber is an ethylene-propylene copolymer rubber or ethylene-propylene-nonconjugated diene with a molar ratio of ethylene to propylene (ethylene/propylene) of 50/50 to 85/15. Thermoplastic elastomer according to claim 1, characterized in that: 3. The thermoplastic elastomer according to claim 1 or 2, wherein (b) the peroxide crosslinked polyolefin resin is a polyethylene resin. 4. The thermoplastic elastomer according to any one of claims 1 to 3, wherein the crosslinking aid (f) is divinylbenzene. 5 5 to 100 parts by weight of (c) peroxide non-crosslinked hydrocarbon rubber material and/or (d) mineral oil softener are blended with respect to 100 parts by weight of (a) peroxide crosslinked olefin copolymer rubber. The thermoplastic elastomer according to any one of claims 1 to 4, characterized in that: 6. The thermoplastic elastomer according to claim 5, wherein the peroxide non-crosslinked hydrocarbon rubber material (c) is polyisobutylene. 7. The thermoplastic elastomer according to any one of claims 1 to 6, wherein (g) the peroxide non-crosslinked polyolefin resin is a polypropylene resin. 8 (a) 50 to 90 parts by weight of peroxide crosslinked olefin copolymer rubber, (b) 50 to 10 parts by weight of peroxide crosslinked polyolefin copolymer rubber (where (a) + (b) is
up to 100 parts by weight of (c) a peroxide non-crosslinked hydrocarbon-based rubbery material and/or (d) a mineral oil-based softener, as required;
(e) 0.05 to 1% by weight of organic peroxide based on the total amount of each component (a), (b) and (c), (f) crosslinking agent (a), (b)
and (c) 0.07 to 2% by weight based on the total amount of each component.
, (g) a product obtained by dynamic heat treatment in the presence or absence of a peroxide non-crosslinked polyolefin resin, and (h) a polyolefin resin, and (a) and (b). A thermoplastic elastomer characterized in that the total amount of component (g) and component (h) is 10 to 100 parts by weight relative to the total amount of component (g) and component (h). 9. The thermoplastic elastomer according to claim 8, wherein the polyolefin resin (h) is a polyethylene resin or a polypropylene resin.