JP2002020547A - High-tension rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition that has excellent melt tension, melt elongation, mechanical strength, appearance, flexibility (hand feeling) and scratch resistance. SOLUTION: This rubber composition comprises (A) a crosslinkable rubber polymer and (B) a thermoplastic resin and is partially or perfectly crosslinked. In the melting test with the capillary rheometer (the land length: 10 mm; the bore size: 1 mm), the shear melt viscosity (η1) is 102-107 Pa.s at 10 sec-1 shear rate at 200 deg.C and the ratio of η2/η1 is 5-100 (η2: the shear melt viscosity at 103 sec-1 shear rate at 200 deg.C) and the die swell is 1-1.4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a high-tensile rubber composition. More specifically, the present invention relates to a rubber composition having excellent melt tension, melt elongation, mechanical strength, appearance, flexibility (touch), and scratch resistance.

[0002]

2. Description of the Related Art A rubber-like polymer such as a radically crosslinkable olefinic elastomer and an olefinic resin having no radically crosslinkable property such as PP are crosslinked while being melt-kneaded in an extruder in the presence of a radical initiator. Thermoplastic elastomer compositions by dynamic crosslinking are already known technologies and are widely used in applications such as automobile parts. As such an olefin-based elastomer, an ethylene-propylene-diene rubber (EPDM) or an olefin-based elastomer produced by using a metallocene catalyst (Japanese Patent Laid-Open No.
JP-A-201227 and JP-A-9-137001) are known. However, the above composition does not always have sufficient tensile strength, elongation, appearance and mechanical strength at the time of melting, and a rubber composition that can withstand practical use is required.

[0003]

SUMMARY OF THE INVENTION In view of such circumstances, the present invention has no problems as described above, namely, melt tension, melt elongation, mechanical strength, appearance, flexibility (touch) and scratch resistance. An object of the present invention is to provide a rubber composition having excellent properties.

[0004]

Means for Solving the Problems The present inventors have intensively studied a rubber composition having excellent tension at the time of melting, and as a result, having a specific melting property, surprisingly, the melt tension, melt elongation, Flexibility (tactile sensation) as well as mechanical strength and appearance
The inventors have also found that the scratch resistance can be dramatically improved, and the present invention has been completed.

That is, the present invention relates to a rubber composition comprising (A) a crosslinkable rubber-like polymer and (B) a thermoplastic resin, which has been partially or completely crosslinked, and has a melting test (land length of 10 mm) using a capillary rheometer. , A melt temperature of 200 ° C. and a shear melt viscosity η1 at a shear rate of 10 sec ⁻¹ are 10 ² to 10 ⁷ (Pa · s),
The η1, the melting temperature of 200 ° C., and the shear rate of 10 ³ sec ⁻¹
The rubber composition is characterized in that the ratio η1 / η2 to the shear melt viscosity η2 is 5 to 100 and the die swell is 1 to 1.4.

Hereinafter, the present invention will be described in detail. The composition of the present invention is a partially or completely crosslinked rubber composition having specific melting properties and comprising (A) a crosslinkable rubbery polymer and (B) a thermoplastic resin.

Here, in a melting test using a capillary rheometer (land length 10 mm, hole diameter 1 mm), the shear melting viscosity η1 at a melting temperature of 200 ° C. and a shear rate of 10 sec ⁻¹ is 10 ² to 10 ⁷ (Pa · s). Is important, preferably 10 ³ to 10 ⁵ , more preferably 10 ^3
3 to 10 ⁴ (Pa · s). When η1 is less than 10 ² , the melt viscosity is low, and not only the take-off property in extrusion processing is poor, but also the mechanical strength and scratch resistance are reduced. Meanwhile,
When η1 exceeds 10 ⁷ , not only productivity is lowered due to high viscosity, but also appearance and flexibility are inferior.

Next, the ratio η1 / η of η1 to the shearing melt viscosity η2 at a melting temperature of 200 ° C. and a shear rate of 10 ³ sec ^-1
2 is 5 to 100, preferably 5 to 50, more preferably 10 to 50, and most preferably 10 to 30.
Only when η1 / η2 is within the above range, the productivity of extrusion processing,
Appearance and flexibility are improved. And the die swell is 1.4
Exceeds, the appearance and productivity of the extrusion process are significantly inferior,
A die swell of 1 to 1.4 is required, preferably 1 to 1.4.
The inventors have found that it is important to have a die swell of 1.3, more preferably 1 to 1.2, and have completed the present invention.

Hereinafter, each component of the present invention will be described in detail. In the present invention, (A) the crosslinkable rubber-like polymer preferably has a glass transition temperature (Tg) of -30 ° C or lower. Examples of such a rubber-like polymer include polybutadiene and poly (styrene-butadiene). , Poly (acrylonitrile-butadiene) and other diene rubbers and hydrogenated hydrogenated saturated rubbers, isoprene rubber, chloroprene rubber, acrylic rubbers such as polybutyl acrylate, ethylene-propylene copolymer rubber, ethylene-propylene rubber -Diene monomer terpolymer rubber (EPD
M), a crosslinked rubber or a non-crosslinked rubber such as an ethylene-octene copolymer rubber, and a thermoplastic elastomer containing the above rubber component.

In the present invention, among the crosslinkable rubbery polymers (A), an ethylene / α-olefin copolymer is particularly preferred, and ethylene and an α-olefin having 3 to 20 carbon atoms are more preferred. Examples of the α-olefin having 3 to 20 carbon atoms include propylene, butene-1, pentene-1, hexene-1, 4-methylpentene-1, heptene-1, octene-1, nonene-1, decene-1,
Undecene-1, dodecene-1 and the like. Among them, hexene-1, 4-methylpentene-1, octene-1
Is particularly preferable, and an α-olefin having 6 to 12 carbon atoms is particularly preferable, and octene-1 is most preferable.
Octene-1 is excellent in softening effect even in a small amount, and the obtained copolymer is excellent in mechanical strength.

The ethylene / α-olefin copolymer (A) preferably used in the present invention is preferably produced using a known metallocene catalyst. Generally, a metallocene-based catalyst is composed of a cyclopentadienyl derivative of a group IV metal such as titanium or zirconium and a co-catalyst, and is not only highly active as a polymerization catalyst, but also has a higher polymer yield than a Ziegler-based catalyst. Has a narrow molecular weight distribution, and the distribution of the comonomer α-olefin having 3 to 20 carbon atoms in the copolymer is uniform. The ethylene / α-olefin copolymer (A) used in the present invention preferably has an α-olefin copolymerization ratio of 1 to 60% by weight, more preferably 10 to 50% by weight, and most preferably 20 to 50% by weight. 45% by weight. When the copolymerization ratio of the α-olefin exceeds 60% by weight, the hardness and tensile strength of the composition are greatly reduced, while when it is less than 1% by weight, the flexibility and the mechanical strength are reduced.

(A) Ethylene / α-olefin copolymer
Has a density of 0.8 to 0.9 g / cm. ^ThreeIn the range of
Is preferred. Olefin based elastomers with densities in this range
Excellent flexibility and low hardness by using stoma
A new elastomer composition can be obtained.

(A) Ethylene α used in the present invention
The olefin copolymer preferably has a long-chain branch. The presence of the long-chain branch enables the density to be lower than the ratio (% by weight) of the copolymerized α-olefin without lowering the mechanical strength. Hardness and high strength elastomer can be obtained. The olefin elastomer having a long chain branch is described in US Pat. No. 5,278,272 and the like. The (A) ethylene / α-olefin copolymer preferably has a DSC melting point peak at room temperature or higher. When it has a melting point peak, the form is stable in the temperature range below the melting point, the handleability is excellent, and the stickiness is small. The melt index of (A) used in the present invention is 0.01 to 100 g / 10 min (19
(0 ° C., 2.16 kg load) is preferably used, and more preferably 0.2 to 10 g / 10 min.
If the amount exceeds 100 g / 10 minutes, the crosslinkability of the composition will be insufficient, and if it is less than 0.01 g / 10 minutes, the fluidity will be poor and the processability will be undesirably reduced.

(A) used in the present invention may be a mixture of a plurality of types. In such a case, it is possible to further improve the workability. In the present invention, one of the preferred crosslinkable rubbery polymers among (A) is a thermoplastic elastomer, and among them, a polystyrene thermoplastic elastomer is particularly preferred, and a block comprising an aromatic vinyl unit and a conjugated diene unit is preferred. Copolymers and block copolymers in which the conjugated diene unit is partially hydrogenated or epoxy-modified are mentioned.

The aromatic vinyl monomer constituting the block copolymer is, for example, styrene, α-methylstyrene, paramethylstyrene, p-chlorostyrene, p-bromostyrene, 2,4,5-tribromobenzene. Styrene is the most preferable, and styrene is most preferable. However, other aromatic vinyl monomers described above may be copolymerized mainly with styrene. Further, the conjugated diene monomer constituting the block copolymer,
Examples thereof include 1,3-butadiene and isoprene. In the block structure of the block copolymer, a polymer block composed of an aromatic vinyl unit is represented by S, and a polymer block composed of a conjugated diene and / or a partially hydrogenated unit thereof is represented by B. In case, SB, S
(BS) n, (where n is an integer of 1 to 3), S (BS
B) n, (where n is an integer of 1 to 2) linear block copolymer or (SB) nX (where n is an integer of 3 to 6; X is silicon tetrachloride, tin tetrachloride, poly A coupling agent residue such as an epoxy compound), and is preferably a star-shaped (star) block copolymer having a portion B as a bonding center. Above all, type 2 of SB, type 3 of SBS, SB
SB type 4 linear-block copolymers are preferred.

In the present invention, another preferred hydrogenated copolymer of (A) is an unsaturated rubber comprising a polymer having a double bond in a main chain and a side chain and / or a random copolymer. More than 50% of the double bonds are hydrogenated rubber. The total double bonds in the hydrogenated rubber are 50% or more, preferably 90% or more, more preferably 95% or more, and the remaining double bonds in the main chain are 5% or less, and the side chains are Is preferably 5% or less. Specific examples of such rubbers include polybutadiene, poly (styrene-butadiene),
Rubbery polymers obtained by partially or completely hydrogenating diene rubbers such as poly (acrylonitrile-butadiene), polyisoprene, and polychloroprene;
Particularly, a hydrogenated butadiene rubber or a hydrogenated isoprene rubber is preferable.

Such a hydrogenated rubber can be obtained by partially hydrogenating the above rubber by a known hydrogenation method. For example, FLRamp, etal, J.Amer.Chem.Soc., 83,46
72 (1961) .Method of hydrogenation using triisobutylborane catalyst described in Hung Yu Chen, J. Polym. Sci. Polym. Lette
r Ed., 15,271 (1977) Hydrogenation using toluenesulfonyl hydrazide, or hydrogenation using an organic cobalt-organoaluminum catalyst or an organic nickel-organoaluminum catalyst described in JP-B-42-8704. And the like. Here, a particularly preferred method of hydrogenation is disclosed in JP-A-59-133203, JP-A-60-220147, which uses a catalyst capable of hydrogenation under mild conditions of low temperature and low pressure, or in an inert organic solvent. JP-A-62-207303 in which hydrogen is brought into contact with a bis (cyclopentadienyl) titanium compound in the presence of a catalyst comprising a hydrocarbon compound having a sodium, potassium, rubidium or cesium atom. This is the method shown in FIG. The Mooney viscosity (ML) of the hydrogenated rubber measured at 100 ° C. may be 20 to 90, and the 5% by weight styrene solution viscosity (5% SV) at 25 ° C. may be in the range of 20 to 300 centipoise (cps). preferable. A particularly preferred range is 25 to 150 cps.

The control of the endothermic peak heat quantity, which is an index of the crystallinity of the hydrogenated rubber, is performed by adding a polar compound such as tetrahydrofuran or controlling the polymerization temperature. The reduction of the endothermic peak calorific value is achieved by increasing the amount of the polar compound or decreasing the polymerization temperature to increase the 1,2-vinyl bond. (A) used in the present invention
May be used as a mixture of a plurality of types. In such a case, it is possible to further improve the workability. (A) used in the present invention may be a mixture of a plurality of types. In such a case, it is possible to further improve the workability.

In the present invention, (B) the thermoplastic resin comprises:
There is no particular limitation as long as it can be dispersed with (A). For example, polystyrene, polyphenylene ether,
Polyolefin type, polyvinyl chloride type, polyamide type,
Polyesters, polyphenylene sulfides, polycarbonates, polymethacrylates and the like can be used alone or in combination of two or more. In particular, olefin resins such as ethylene resins and propylene resins are preferable as the thermoplastic resin. Specific examples of the propylene-based resin most preferably used in the present invention, homo isotactic polypropylene, propylene and ethylene,
Other α- such as butene-1, pentene-1, hexene-1
Examples include an isotactic copolymer resin with olefin (including block and random). The propylene-based resin used in the present invention has a melt index of 0.1 to 100 g / 10 min (230 ° C., 2.16 k
g load) is preferably used. 100g
If the heating time exceeds / 10 minutes, the heat resistance and mechanical strength of the thermoplastic elastomer composition are insufficient, and 0.1 g / 10
If it is less than minute, the fluidity is poor and the molding processability is undesirably reduced.

In the present invention, among (B), (B-1) a propylene random copolymer resin such as a random copolymer resin of ethylene and propylene; and (B-2) a propylene block copolymer resin or a homopolymer. The combination with a polypropylene resin is most preferred. The appearance and mechanical strength are further improved by combining such two types of olefin resins, such as a crosslinked olefin resin and a decomposed olefin resin. As (B-1), for example, a random copolymer resin of ethylene and propylene can be mentioned. When an ethylene component is present in the polymer main chain, it becomes a cross-linking point of a cross-linking reaction. Show characteristics. It is preferable that (B-2) contains an α-olefin as a main component and does not contain an ethylene unit in the polymer main chain. However, when an ethylene-α-olefin copolymer is present as a dispersed phase, such as a propylene-based block copolymer resin, it exhibits the properties of a decomposable olefin-based resin. (B) may be a combination of a plurality of (B-1) and (B-2) components.

The melt index of the olefin resin preferably used in the present invention is 0.1 to 100 g.
/ 10 minutes (230 ° C., 2.16 kg load) are preferably used. If it exceeds 100g / 10 minutes,
The heat resistance and mechanical strength of the thermoplastic elastomer composition are insufficient, and if it is less than 0.1 g / 10 minutes, the fluidity is poor and the molding processability is undesirably reduced.

In 100 parts by weight of the composition comprising (A) and (B), (B) is used in a composition ratio of 1 to 99 parts by weight. Preferably 5 to 90 parts by weight, more preferably 2
0 to 80 parts by weight. If the amount is less than 1 part by weight, the fluidity and processability of the composition are reduced, and if it exceeds 99 parts by weight, the flexibility of the composition is insufficient, which is not desirable. The partially or completely crosslinked rubber composition of the present invention is preferably crosslinked with (C) a crosslinking agent. (C) contains (C-1) a crosslinking initiator as an essential component, and optionally contains (C-2) a polyfunctional monomer and (C-3) a monofunctional monomer. The above (C)
Is used in an amount of 0.01 to 10 parts by weight, preferably 0.05 to 3 parts by weight, based on 100 parts by weight of the composition comprising (A) and (B). If the amount is less than 0.01 part by weight, the crosslinking is insufficient, and if it exceeds 10 parts by weight, the appearance and mechanical strength of the composition decrease.

Here, examples of the (C-1) crosslinking initiator include radical initiators such as organic peroxides and organic azo compounds, and specific examples thereof include 1,1-bis (t-butyl). Peroxy) -3,3,5-trimethylcyclohexane,
1,1-bis (t-hexylperoxy) -3,3,5
-Trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-
Butylperoxy) cyclododecane, 1,1-bis (t
-Butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) octane, n-butyl-4,
Peroxy ketals such as 4-bis (t-butylperoxy) butane and n-butyl-4,4-bis (t-butylperoxy) valerate; di-t-butyl peroxide, dicumyl peroxide, t -Butylcumyl peroxide, α, α′-bis (t-butylperoxy-m
-Isopropyl) benzene, α, α'-bis (t-butylperoxy) diisopropylbenzene, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5 Dialkyl peroxides such as -bis (t-butylperoxy) hexine-3; acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexa Diacyl peroxides such as noyl peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide and m-trioyl peroxide; t-butylperoxyacetate, t
-Butylperoxyisobutyrate, t-butylperoxy-2-ethylhexanoate, t-butylperoxylaurate, t-butylperoxybenzoate,
Di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, and cumylperoxyoctate Peroxyesters; and
Hydrogen such as t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide and 1,1,3,3-tetramethylbutyl peroxide Peroxides can be mentioned.

Among these compounds, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl -2,5-bis (t-butylperoxy) hexane and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3 are preferred.

The above (C-1) preferably accounts for 1 to 80% by weight, more preferably 10 to 50% by weight, of the component (C).
Is used. If the amount is less than 1% by weight, crosslinking is insufficient, and if it exceeds 80% by weight, the mechanical strength decreases. In the present invention, one of the (C-2) polyfunctional monomers of the crosslinking agent (C) is preferably a radically polymerizable functional group as a functional group, particularly preferably a vinyl group. The number of the functional groups is two or more, but it is effective especially in the case of having three or more functional groups in combination with (C-3). Specific examples include divinylbenzene, triallyl isocyanurate,
Triallyl cyanurate, diacetone diacrylamide, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, ethylene glycol dimethacrylate,
Triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diisopropenylbenzene, P-quinone dioxime, P, P'-dibenzoylquinone dioxime, phenylmaleimide, allyl methacrylate, N, N'-m-phenylenebismaleimide, diallyl Phthalate, tetraallyloxyethane, 1,2
-Polybutadiene and the like are preferably used. Particularly, triallyl isocyanurate is preferable. These polyfunctional monomers may be used in combination of two or more.

The above (C-2) is preferably 1 to 80% by weight, more preferably 10 to 50% by weight in the component (C).
Is used. If the amount is less than 1% by weight, crosslinking is insufficient, and if it exceeds 80% by weight, the mechanical strength decreases. The (C-3) used in the present invention is a vinyl monomer added for controlling a crosslinking reaction rate, preferably a radical polymerizable vinyl monomer, and an aromatic vinyl monomer and acrylonitrile. , Unsaturated nitrile monomers such as methacrylonitrile, acrylic acid ester monomers, methacrylic acid ester monomers, acrylic acid monomers, methacrylic acid monomers, maleic anhydride monomers, N-substituted maleimides Monomers and the like can be mentioned.

The above (C-3) is preferably 1 to 80% by weight, more preferably 10 to 50% by weight in the component (C).
Is used. If the amount is less than 1% by weight, crosslinking is insufficient, and if it exceeds 80% by weight, the mechanical strength decreases.

The above (D) is preferably a paraffinic or naphthenic process oil. These are used for adjusting the hardness and flexibility of the composition in an amount of 5 to 500 parts by weight, preferably 10 to 150 parts by weight, per 100 parts by weight of the composition comprising (A) and (B). If less than 5 parts by weight, flexibility,
If the workability is insufficient, and if it exceeds 500 parts by weight, oil bleed becomes remarkable, which is not desirable.

The shear melt viscosity in the melt test in the present invention is controlled by the molecular weights of the components (A) and (B), the type and amount of the crosslinking initiator and crosslinking aid, the amount added, the reaction temperature, and the reaction system. More specifically, the shear melt viscosity η1 at a melt temperature of 200 ° C. and a shear rate of 10 sec ⁻¹ is (A), (B)
It increases as the molecular weight of the component increases. Also, η1 / η
As for the ratio 2 and the die swell, even when the average molecular weights of (A) and (B) are the same, the η1 / η2 ratio and the die swell decrease as the molecular weight distribution increases. The morphology of the composition comprising the components (A) and (B) is also important. When the component (A) exists as independent particles and the component (B) is a continuous phase, the η1 of the present invention is used. Satisfies the requirements of / η2 ratio and die swell. In order to achieve the above morphology, for example, it is important to suppress the crosslinking rate under a high shear force. Specifically, this can be achieved by reducing the amount of the crosslinking initiator or the crosslinking assistant and conducting the reaction at a temperature as low as possible and for a long time, which is higher than the decomposition temperature of the crosslinking initiator. It can also be achieved by using a polyfunctional monomer and a monofunctional monomer in combination as a crosslinking aid. Excessive addition of a crosslinking initiator and a crosslinking aid, or excessively high activity of a crosslinking initiator, a crosslinking aid and high-temperature reaction conditions cause aggregation of the rubbery polymer and do not satisfy the requirements of the present application. By mixing a crosslinking initiator and a crosslinking assistant into (A) while preliminarily absorbing a small amount of (D) a softening agent in (A), the crosslinking reaction proceeds gently. Can be generated.

The composition of the present invention is obtained by combining (A) a crosslinkable rubber-like polymer described above, (B) a thermoplastic resin such as an olefin resin, and (D) a softener in a specific composition ratio. , Melt tension, melt elongation, mechanical strength and flexibility,
The balance of processability is improved, and it can be preferably used.

Further, the composition of the present invention can contain an inorganic filler and a plasticizer to such an extent that its characteristics are not impaired. Examples of the inorganic filler used here include calcium carbonate, magnesium carbonate, silica, carbon black, glass fiber, titanium oxide, clay, mica, talc, magnesium hydroxide, and aluminum hydroxide. As the plasticizer, for example, polyethylene glycol, dioctyl phthalate (DO)
And phthalic acid esters such as P). Also, other additives such as organic / inorganic pigments, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, flame retardants, silicone oils, antiblocking agents, foaming agents, antistatic agents, antibacterial agents, etc. Are also preferably used.

For the production of the composition of the present invention, general methods such as a Banbury mixer, a kneader, a single screw extruder, a twin screw extruder and the like used in the production of ordinary resin compositions and rubber compositions are employed. It is possible to In particular, a twin-screw extruder is preferably used to achieve dynamic crosslinking efficiently. The twin-screw extruder is used for dispersing (A) and (B) uniformly and finely and further adding other components to cause a cross-linking reaction to continuously produce the composition of the present invention. ,
More suitable.

The composition of the present invention is preferably used as a specific example.
It can be manufactured through the following processing steps.
That is, (A) and (B) are mixed well and put into a hopper of an extruder. (C) may be added together with (A) and (B) from the beginning, or may be added from the middle of the extruder. The oil may be added from the middle of the extruder, or may be added separately at the beginning and during the middle. A part of (A) and (B) may be added in the middle of the extruder. When heated and melted and kneaded in an extruder, the above (A) and (C)
And (D) a softening agent is added and the mixture is melt-kneaded to make the cross-linking reaction and kneading dispersion sufficient, and then the mixture is removed from the extruder to obtain pellets of the composition of the present invention. it can.

A particularly preferred melt extrusion method is to have a length L in the die direction from the raw material addition portion and
This is the case where a twin-screw extruder with / D of 5 to 100 (where D is the barrel diameter) is used. The twin-screw extruder has a main feed and a side feed that differ in distance from the tip.
A supply portion at a plurality of locations of the contact portion, and a kneading portion between the plurality of supply portions and between the distal end portion and the supply portion located at a short distance from the distal end portion. It is preferable that the length of each of the padding portions is 3D to 10D.

One twin screw extruder of the manufacturing apparatus used in the present invention may be a twin screw co-rotating extruder or a twin screw different-direction rotary extruder. For screw engagement, non-engagement type, partial engagement type,
There is a complete meshing type, and any type may be used. In order to obtain a uniform resin at a low temperature by applying a low shear force, a screw in a different direction / partial engagement type is preferably used. When slightly large kneading is required, a co-rotating / completely meshing screw is preferable. If even greater kneading is required, a co-rotating, fully meshing screw
Is preferred.

In the method for producing the composition of the present invention, it is more preferable to satisfy the following kneading degree.

[0037] ^{M = (π 2/2)} (L / D) D 3 (N / Q) 10 × 10 6 ≦ M ≦ 1000 × 10 6 where, L: the raw material added portion as a base point to the die extrusion direction PIC ( mm), D: extruder barrel inner diameter (mm), Q: discharge amount (kg / h), N: screw rotation speed (rpm) kneading degree ^{M = (π 2/2)} (L / D) D 3 (N / Q) is 1
It is important that 0 × 10 ⁶ ≦ M ≦ 1000 × 10 ⁶ . When M is less than 10 × 10 ⁶ , the appearance is deteriorated because the rubber particles are enlarged and agglomerated, while M is 1000 × 10 ⁶
Exceeding the mechanical strength decreases due to excessive shearing force.

To achieve better appearance and mechanical strength, it is preferable to satisfy the melting temperature of the following relational expression. That is, first, melt-kneading is performed at a melting temperature T ₂ (° C.), and then melt-kneading is performed at a melting temperature T ₃ (° C.). 0.1 L to 0.5 L from the addition port
Is extruded at the melting temperature T ₂ (° C.) first, and then the extruder zone is melted at the melting temperature T ₃ (° C.).
(° C).

Here, it is particularly preferred that T ₁ is 150 to 250 ° C., and T ₁ or T _{2 in} each zone of the melt extruder may be a uniform temperature or have a temperature gradient. Is also good.

T ₁ : 1 minute half-life temperature of the peroxide (C-1) (° C.) T ₁ -100 <T ₂ <T ₁ +40 T ₂ +1 <T ₃ <T ₂ +200 The rubber composition thus obtained Various molded articles can be manufactured by any molding method. Injection molding, extrusion molding, compression molding, blow molding, calender molding, foam molding and the like are preferably used.

[0041]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In these examples and comparative examples, the test methods used for evaluating various physical properties are as follows.

(1) Melt Test Using a capillary rheometer, Capillograph 1C / 3A manufactured by Toyo Seiki Seisaku-sho, Ltd., a capillary flow test, a die swell, a melt tension, and a melt elongation of the molten polymer were measured. Capillary flow test The following conditions were kept constant, the shear rate was changed, and the shear melt viscosity (η1, η2) and die swell were measured. Land length 10mm, orifice hole diameter 1mm, melting temperature 20
At 0 ° C., the die swell was measured by irradiating the molten polymer 10 mm from the end face of the orifice with a laser beam. -Melt tension and melt elongation The take-up speed was changed under the following conditions, and the melt tension at each take-up speed was measured. At that time, the take-off speed at the time of yarn breakage was used as an index of melt elongation. Land length 10m
m, orifice hole diameter 1 mm, melting temperature 200 ° C, crosshead speed 50 mm / min

(2) Tensile breaking strength [MPa] From a T-die extruded sheet, a value of 2 was obtained according to JIS K6251.
The evaluation was performed at 3 ° C. (3) Appearance The appearance of the sheet was evaluated based on the following criteria. ◎ Extremely good ○ Good △ Good, but somewhat rough × Overall rough. No gloss (4) Flexibility (tactile sensation) Flexibility was evaluated from the sheet skin according to the following criteria. ◎ Extremely flexible and good touch feeling ○ Good △ Good, but somewhat hard feeling × Hard overall and poor touch feeling

(5) Scratch resistance A sheet having a rectangular tip with a length of 10 mm and a width of 1 mm and a weight of 300 g dropped from a height of 5 cm onto a sheet was visually inspected for scratches on the sheet according to the following criteria. An evaluation was performed. Very good ○ Good △ Good, but scratches are noticeable × Damage is remarkable (6) Analysis of conjugated diene rubber 1) Hydrogenation rate (%) Measured by NMR according to the following procedure.

First, the polybutadiene rubber before hydrogenation was dissolved in deuterated chloroform, and FT-NMR (270 Meg.,
Proton (= CH ₂ ) with 1,2-vinyl having a chemical shift of 4.7 to 5.2 ppm (referred to as signal C0) and a chemical shift of 5.2 to 5.8 ppm (referred to as signal D0) at JEOL. From the integrated intensity of the vinyl proton (= CH ₂ ). (V) = [0.5C0 / {0.5C0 + 0.5 (D0-0.5C0)}] × 100

Next, the polybutadiene rubber after the partial hydrogenation was dissolved in deuterated chloroform, and similarly, by FT-NMR, the hydrogenated 1,1 having a chemical shift of 0.6 to 1.0 ppm (referred to as signal A1) was obtained. Methyl proton (—CH ₃ ) due to two bonds, chemical shift 4.7 to 5.2 ppm
1,2 not hydrogenated (referred to as signal C1)
-Proton (= CH ₂ ) by vinyl, chemical shift 5.
It was calculated from the integrated intensity of the unhydrogenated vinyl proton (= CH ₂ ) of ₂ to 5.8 ppm (referred to as signal D1) by the following equation. First, p = 0.5C0 / (0.5C1 + A1 / 3) A11 = pA1, C11 = pC1, D11 = pD1, and the hydrogenation rate of the 1,2-vinyl bond (B) (B) = [(A11 / 3 ) / ｛A11 / 3 + C11 /
2｝] × 1001,4-hydrogenation rate of double bond part (C) (C) = [｛0.5 (D0-0.5C0) -0.5 (D
11-0.5C11)｝ / 0.5 (D0-0.5C
0)] × 100 Hydrogenation rate of whole butadiene part (A) (A) = (V) × (B) / 100 + [100− (V)]
× (C) × 100

2) Microstructure The symbols defined above are described below. 1,2-vinyl bond before hydrogenation = (V) × (B) / 1
00 (%) 1,4 bonds before hydrogenation = {100- (V)} × (C)
/ 100 (%) 1,2-vinyl bond after hydrogenation = (V) × {100- (B)} / 100 (%) 1,4-bond after hydrogenation = {100- (V)} × ｛ 1
00- (B)｝ / 100 (%)

(7) Light stability As a light stability tester, ATLAS Electric Devices Co., USA
JIS K71 using ATLAS CI35W Weatherometer made by
02. Irradiation conditions were: internal temperature of tester, 55 ° C., humidity 55%, no rain, xenon light (wavelength 340 nm, energy 0.30 W / m ² ) 3
The irradiation was performed for 00 hours. After irradiation, the appearance of the sheet was visually evaluated according to the following criteria. ◎ Extremely good ○ Good △ Good, but somewhat rough × Overall rough. No luster

The following components were used in Examples and Comparative Examples. (A) Rubbery polymer 1) Copolymer of ethylene and octene-1 (TPE-
1) It was prepared by a method using a metallocene catalyst described in JP-A-3-1630088. The ethylene / octene-1 composition ratio of the copolymer is 72/28 (weight ratio).
(Referred to as TPE-1) 2) Copolymer of ethylene and octene-1 (TPE-
2) It was produced by a method using a usual Ziegler catalyst. The ethylene / octene-1 composition ratio of the copolymer is 72/2.
8 (weight ratio). (Referred to as TPE-2)

3) Ethylene / propylene / dicyclopentadiene copolymer (TPE-3) Produced by a method using a metallocene catalyst described in JP-A-3-1630088. The composition ratio of ethylene / propylene / dicyclopentadiene in the copolymer is 72/2.
4/4 (weight ratio). (Referred to as TPE-3)

4) Polybutadiene rubber having a hydrogenation rate of 0 to 100 (%) (b) Olefin-based resin Polypropylene (PP) Isotactic homopolypropylene manufactured by Japan Polyolefin Co., Ltd. (c) Crosslinking agent 1) Crosslinking initiator ( C-1) Nippon Yushi Co., Ltd., 2,5-dimethyl-2,5-bis (t-
Butylperoxy) hexane (trade name Perhexa 25)
B) (referred to as POX-1) 2) Crosslinking initiator (C-1) 2,5-dimethyl-2,5-bis (t-manufactured by NOF Corporation)
(Butyl peroxy) hexyne-3 (trade name: Perhexin 25B) (referred to as POX-2) 3) Polyfunctional monomer (C-2) manufactured by Wako Pure Chemical Industries, Ltd., divinylbenzene (referred to as DVB) 4) Polyfunctional Monomer (C-2) Triallyl isocyanurate (TA) manufactured by Nippon Kasei Co., Ltd.
5) Polyfunctional monomer (C-2), N, N'-m phenylenebismaleimide (PMI) manufactured by Ouchi Shinko Chemical Co., Ltd. 6) Monofunctional monomer (C-3) 7) Methyl methacrylate (MMA) manufactured by Asahi Chemical Industry Co., Ltd. 7) Monofunctional monomer (C-3) Styrene (ST) manufactured by Asahi Chemical Industry Co., Ltd. (d) Paraffin oil Idemitsu Kosan ( Diana Process Oil PW-9
0 (referred to as MO)

[0052]

Examples 1 to 7 Comparative Examples 1 to 4 A twin-screw extruder (25 mm) consisting of 11 blocks having an inlet at the center of the barrel.
(φ, L / D = 47), (A) TPE-1 / (B) PP / (C
-1) POX / (C-2) DVB / (D) MO = 70/30 / 0.5 /
A composition consisting of 1.0 / 40 (weight ratio) was melt-kneaded in the following manner on the basis of the following melting conditions. As the screw, a double screw having a kneading portion before and after the injection port was used. The shear melt viscosity in the melt test was controlled by the molecular weights of the components (A) and (B), the type of the crosslinking initiator and the crosslinking assistant, the amounts added, the reaction temperature, and the reaction method according to the method described above. Specifically, the molecular weight of PP, PO
This was performed by changing the amounts of X and DVB, the screw rotation speed, and the cylinder set temperature.

(Standard Melting Conditions) 1) Melt extrusion temperature constant at 220 ° C. 2) Discharge rate Q = 12 kg / h 3) Extruder barrel inner diameter D = 25 mm 4) L / L when extruder length is L (mm) D = 475 5) Screw rotation speed N = 280 rpm From the elastomer composition thus obtained, 200
A sheet having a thickness of 2 mm was prepared by compression molding at a temperature of ° C., and each characteristic was evaluated. The results are shown in Table 1.

[0054]

[Table 1] According to Table 1, it can be seen that when the melting properties required for the present invention are satisfied, the melt tension, melt elongation, tensile breaking strength, appearance, flexibility, and scratch resistance are excellent.

[0055]

Examples 8 to 17 In Example 1, (A)
Polybutadiene rubber with hydrogenation rate of 0 to 100 (%), TP
The same experiment was repeated, except that E-2 and TPE-3 were changed. The results are shown in Table 2.

[0056]

[Table 2] According to Table 2, as (A), ethylene and carbon number 3 to 2
50 of the total double bonds of an unsaturated rubber consisting of an ethylene / α-olefin copolymer comprising α-olefin of 0 and / or a homopolymer having a double bond in the main chain and a side chain and / or a random copolymer. It can be seen that when a hydrogenated rubber with hydrogen content of at least% is used, the melt tension, melt elongation, tensile breaking strength, appearance, flexibility, and scratch resistance are excellent.

[0057]

Examples 18 to 27 Comparative Examples 6 to 7 In Example 1, melt-kneading is performed first at a melting temperature T ₂ (° C.) and then at a melting temperature T ₃ (° C.) according to the following definition. Further, instead of (C-2) DVB, (C-2) shown in Table 3
-2) The same experiment was repeated except for changing to (C-3). Table 3 shows the results. When (C-2) and (C-3) were used in combination, both were used in the same amount.

[0058]

[Table 3] According to Table 3, by manufacturing under the following melting conditions,
It can be seen that melt tension, melt elongation, tensile breaking strength, appearance, flexibility, and scratch resistance are improved.

[0059] _{T 1: (C-1)} 1 -minute half-life temperature of the peroxide (° C.) T ₁ over _{100 <T 2 <T 1 +40} T 2 +1 <T 3 <T 2 +200

[0060]

Examples 28 to 30 Comparative Examples 8 to 10 The same experiment as in Example 1 was repeated, except that the kneading degree was changed according to the following definition. Table 4 shows the results.

[0061] ^{M = (π 2/2)} (L / D) D 3 (N / Q) where, L: the raw material added portion die direction of extrusion captain as a base point (mm), D: extruder barrel inner diameter (mm ), Q: Discharge rate (kg /
h), N: screw rotation speed (rpm) D = 25 mm
L / D = 47

[0062]

[Table 4] According to Table 4, the melt tension, the melt elongation, the tensile strength at break, the appearance, the flexibility, and the scratch resistance are improved by manufacturing in the range of the kneading degree M of 10 × 10 ⁶ ≦ M ≦ 1000 × 10 ^6. You can see that.

[0063]

The rubber composition according to the present invention is excellent in melt tension, melt elongation, mechanical strength, appearance, flexibility (touch) and scratch resistance. The rubber composition of the present invention is used for automobile parts, automobile interior materials, airbag covers, mechanical parts, electric parts, cables, hoses, belts, toys, miscellaneous goods, daily necessities, building materials, sheets, films, etc. It can be used widely and plays a large role in the industrial world.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (reference) C08L 91/00 C08L 91/00 101/00 101/00 F term (reference) 4J002 AA01X AC00W AC03W AC06W AC07W AC08W AC09W AE05Y BB00X BB02X BB05W BB11X BC02X BD03X BG05X CF00X CG00X CH07X CL00X CN01X EK006 EK036 EK046 EK056 EK066 FD02Y FD146 GN00

Claims (4)

[Claims] 1. A melting test using a capillary rheometer (land length 10 mm, pore diameter 1 mm) in a partially or completely crosslinked rubber composition comprising (A) a crosslinkable rubbery polymer and (B) a thermoplastic resin. ) At a melting temperature of 200 ° C. and a shear rate of 10 sec ^−1.
1 is 10 ² to 10 ⁷ (Pa · s), the ratio η1 / η2 of η1 to the shearing melt viscosity η2 at a melting temperature of 200 ° C. and a shear rate of 10 ³ sec ⁻¹ is 5 to 100, and Is from 1 to 1.4. 2. Melting temperature 200 ° C., shear rate 10 sec.
The shear melt viscosity η1 of c ^-1 is 10 ³ to 10 ⁵ (Pa ·
s), wherein η1 / η2 is 10 to 50 and die swell is 1 to 1.2.
The rubber composition as described in the above. 3. (A) is ethylene and α having 3 to 20 carbon atoms.
-50% or more of the total double bonds of the unsaturated rubber composed of an ethylene / α-olefin copolymer containing an olefin, or a homopolymer and / or a random copolymer having a double bond in a main chain and a side chain, 3. The rubber composition according to claim 1, which is one or more crosslinkable rubbery polymers selected from hydrogenated hydrogenated rubbers. 4. The rubber composition according to claim 1, wherein the rubber composition is crosslinked with a crosslinking agent (C) and further contains (D) a softening agent.