JPH06128427A - Ethylene-alpha-olefin-7-methyl-1,6-octadiene copolymer rubber composition - Google Patents

Abstract

PURPOSE:To provide a rubber composed of a random copolymer rubber of ethylene-alpha-olefin-methyloctadiene synthesized in the presence of a catalyst such as zirconium and a conjugated diene rubber and excellent in low-temperature flexibility, abrasion resistance and fatigue resistance. CONSTITUTION:This composition is composed of (A) an ethylene-alpha-olefin-7- methyl-1,6-octadiene random copolymer exhibiting 40/60 to 90/10 molar ratio of ethylene/alpha-olefin, >=0.1dl/g and <=8dl/g intrinsic viscosity in decalin at 135 deg.C, <=0.5 intensity ratio of Talphabeta/Talphaalpha in <13>C-NMR spectra and 1.00 to 1.5 B value calculated from <13>C-NMR spectra and B=POE(2PEPO) (PE is content of ethylene unit except octadiene-derived ethylene unit on molar ratio base; PO is alpha-olefin unit content on molar ratio base; POE is ratio of number of alpha-olefin-ethylene chain to number of the whole dyad chain and (B) conjugated diene rubber.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION The present invention relates to an ethylene / α-olefin / 7-methyl-1,6-octadiene copolymer rubber composition, and more specifically, it has excellent covulcanizability with a conjugated diene rubber. , Natural rubber (NR), styrene
Butadiene rubber (SBR), isoprene rubber (IR),
Addition of excellent weather resistance, ozone resistance, heat aging resistance and low temperature flexibility without deteriorating the excellent mechanical properties, abrasion resistance and dynamic fatigue resistance of conjugated diene rubbers such as butadiene rubber (BR). Ethylene which can give sulfurized rubber
The present invention relates to an α-olefin / 7-methyl-1,6-octadiene copolymer rubber composition.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Ethylene / propylene / diene rubber (EPDM) is excellent in weather resistance, ozone resistance and heat aging resistance because it has no double bond in the main chain of its molecular structure. By taking advantage of its characteristics, it is widely used in parts such as weather stripping, door glass run channel, radiator hose where static force is applied to automobile parts.

On the other hand, most of the parts, such as tires, anti-vibration rubbers, wiper blades, which require mechanical strength against dynamic forces, have N having a double bond in the main chain of the molecular structure.
Conjugated diene rubbers such as R, SBR, IR and BR, or blends thereof are used.

By the way, with the recent improvement in the performance of automobiles, it is desired to improve the heat aging resistance and weather resistance of automobile parts. However, although the conjugated diene rubber is excellent in dynamic mechanical properties (dynamic fatigue resistance), it is poor in heat resistance and weather resistance. On the other hand, EPDM is excellent in weather resistance, ozone resistance and heat aging resistance, but has poor dynamic mechanical properties.

Therefore, in order to make the best use of the advantages of these materials by blending EPDM with conjugated diene rubbers,
There have been many studies on blends of PDM and conjugated diene rubber.

The existing technology relating to the blending of EPDM and conjugated diene rubber in the above research is described by Yasuhiro Oda and Masashi Aoshima in "The Rubber Society of Japan, 51, 685 (1).
978) ”, and as the blending method, (1) polysulfide vulcanization, (2) peroxide vulcanization, (3) application of prevulcanized EPDM, (4) application of high iodine value EPDM, ( 5) Application of halogenated EPDM,
(6) The use of accelerators having long-chain alkyl groups and the like are introduced.

However, none of these have practical effects, and few of them are currently commercialized. The reason for this is that the vulcanization rate of the conventional EPDM is basically much slower than that of the conjugated diene rubber.
That is, since the vulcanization rate of EPDM is low, there is a problem that the mixture of EPDM and the conjugated diene rubber is not sufficiently vulcanized with each other and therefore the mechanical strength is lowered.

Therefore, the conjugated diene rubber and EP
In order to obtain a rubber composition having both advantages of DM, it has a low-temperature flexibility equivalent to that of a conjugated diene rubber, and has heat resistance and weather resistance equivalent to those of conventional EPDM, The advent of polymers with fast vulcanization rates was strongly desired.

Incidentally, Japanese Patent Laid-Open No. 2-51512 discloses that
An unsaturated ethylene / α-olefin random copolymer having a characteristic that the vulcanization rate is higher than that of a conventional unsaturated ethylene / α-olefin random copolymer is described. The unsaturated ethylene described in this publication
The α-olefin random copolymer is a random copolymer comprising ethylene, an α-olefin having 3 to 12 carbon atoms, and a non-conjugated diene compound represented by the following general formula [I], and 1) polystyrene Converted number average molecular weight 3,000 to 50
20,000, 2) polystyrene equivalent weight average molecular weight 6,000 to 5,
, 000,000, 3) The content of the non-conjugated diene compound is 3 or more in terms of iodine value, 4) The bonding ratio of ethylene and α-olefin is 5 to 90.
It is characterized by being / 95 to 10 (molar ratio).

[0010]

[Chemical 1]

In this formula, n is an integer of 2 to 10 and R
¹ is an alkyl group having 1 to 8 carbon atoms, R ² and R ³ are the same or different hydrogen atoms, or an alkyl group having 1 to 8 carbon atoms.

Further, Japanese Patent Laid-Open No. 2-64111 discloses that
Titanium, zirconium or hafnium metallocene /
A method for producing a low crystallinity, high molecular weight EPDM elastomer using an alumoxane catalyst system catalyst is described.

[0013]

SUMMARY OF THE INVENTION The present invention is intended to solve the problems associated with the prior art as described above, and is a novel ethylene resin having a low temperature flexibility and a vulcanization rate almost equal to those of the conjugated diene rubber. By providing an α-olefin / 7-methyl-1,6-octadiene copolymer rubber, low temperature flexibility and weather resistance can be achieved without impairing the excellent mechanical properties and oil resistance originally possessed by the conjugated diene rubber. An object of the present invention is to provide a rubber composition capable of imparting a vulcanized rubber excellent in heat resistance and heat resistance.

[0014]

SUMMARY OF THE INVENTION A first ethylene / α-olefin / 7-methyl-1,6-octadiene copolymer rubber composition according to the present invention comprises ethylene, α-olefin and 7-methyl.
A rubber composition comprising a random copolymer rubber (1) comprising -1,6-octadiene and a conjugated diene rubber (2), wherein (i) ethylene in the random copolymer rubber (1) To α-olefin molar ratio (ethylene /
α-olefin) is in the range of 40/60 to 90/10, and (ii) 7 in the random copolymer rubber (1).
-Methyl-1,6-octadiene content is in the range of 0.4 to 25 mol%, and (iii) intrinsic viscosity [η] of the random copolymer rubber (1) measured in decalin at 135 ° C.
Is in the range represented by 0.1 dl / g <[η] <8 dl / g, and (iv) ^{13 of the} random copolymer rubber (1).
The intensity ratio D (= Tαβ / Tαα) of Tαβ to Tαα in the C-NMR spectrum is 0.5 or less,
(V) The B value calculated from the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the following formula is 1.
And (vi) the glass transition temperature Tg of the random copolymer rubber (1) determined by DSC is -53.
It is characterized by being below ℃.

B = P _OE / (2P _E · P _O ) In the above formula, P _E is an ethylene unit derived from the 7-methyl-1,6-octadiene component in the random copolymer rubber (1). It is the content mole fraction of the removed ethylene component, and P _O is α in the random copolymer rubber (1).
-Olefin content mole fraction, P _OE is the total dyad (dya) in the random copolymer rubber (1)
d) The ratio of the number of α-olefin / ethylene chains to the number of chains.

The second ethylene / α- according to the present invention
The olefin / 7-methyl-1,6-octadiene copolymer rubber composition is a rubber composition comprising a random copolymer rubber (1) and a conjugated diene rubber (2), Group IVB transition metal compound (a) in which the integrated rubber (1) contains a ligand having a cyclopentadienyl skeleton
And an organoaluminum oxy compound (b)
In the presence of a Group IVB transition metal catalyst-based catalyst, ethylene and α
-Olefin and 7-methyl-1,6-octadiene are copolymerized, and (i) the molar ratio of ethylene and α-olefin in the random copolymer rubber (1) (ethylene / α- (Olefin) is 40/60 to 90/1
And (ii) the content of 7-methyl-1,6-octadiene in the random copolymer rubber (1) is in the range of 0.4 to 25 mol%, and (iii) the random copolymer. The intrinsic viscosity [η] of rubber (1) measured in decalin at 135 ° C. is 0.1 dl / g <[η] <8 dl / g
And (iv) the intensity ratio D (= Tαβ / Tαα) of Tαβ to Tαα in the ¹³ C-NMR spectrum of the random copolymer rubber (1) is 0.5 or less, (v) ¹³ C of the random copolymer rubber (1)
The B value calculated from the NMR spectrum and the above formula is 1.00 to 1.50, and (vi) the glass transition temperature T of the random copolymer rubber (1) determined by DSC.
It is characterized in that g is −53 ° C. or lower.

A zirconium compound is preferably used as the Group IVB transition metal compound (a). In the present invention, the random copolymer rubber (1) includes a zirconium compound containing a ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound (b) and an organoaluminum compound (c).
Ethylene obtained using Group IVB transition metal catalyst
The α-olefin / 7-methyl-1,6-octadiene copolymer rubber is particularly preferable.

In the present invention, the content of the random copolymer rubber (1) is 5 to 95 parts by weight, and the content of the conjugated diene rubber (2) is 5 to 95 parts by weight. desirable. However, the total amount of (1) and (2) is 100 parts by weight.

[0019]

Detailed Description of the Invention Ethylene / α according to the present invention
The olefin / 7-methyl-1,6-octadiene copolymer rubber composition will be specifically described.

Ethylene / α-olefins according to the present invention
The 7-methyl-1,6-octadiene copolymer rubber composition is composed of a specific random copolymer rubber (1) and a conjugated diene rubber (2).

Random Copolymer Rubber (1) The random copolymer rubber (1) used in the present invention comprises ethylene, α-olefin, 7-methyl-1,6-octadiene (hereinafter abbreviated as MOD). There is)) and.

The α-olefin used in the present invention is an α-olefin having 3 to 20 carbon atoms, specifically, propylene, 1-butene, 1-pentene, 1-hexene,
3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl
-1-Pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-
Examples include pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene. These α-olefins are
Or they are used in combination.

In the present invention, α-olefin having 3 to 6 carbon atoms is preferably used, and α-olefin having 3 carbon atoms is particularly preferable.
-Olefin, ie propylene is preferably used. The present inventors provide a rubber composition capable of providing a vulcanized rubber excellent in low-temperature flexibility, weather resistance and heat resistance without impairing the excellent mechanical properties and oil resistance originally possessed by the conjugated diene rubber. By conducting diligent research to obtain ethylene, propylene, and MOD by the following method, and further controlling the polymerization reaction conditions so as to obtain the following polymer structure and quality, conjugated diene such as NR and SBR can be obtained. It has been found that an EPDM can be obtained which exhibits a vulcanization rate equivalent to that of a system rubber and can provide a rubber composition capable of imparting a vulcanized rubber excellent in the above properties. In addition, ethylene consisting of ethylene, an α-olefin other than propylene, and MOD
It was also found that the α-olefin / 7-methyl-1,6-octadiene copolymer rubber also has the above-mentioned characteristics.

In the present invention, ethylene, α-olefin and M are added in the presence of a specific Group IVB transition metal catalyst system catalyst.
A specific random copolymer rubber (1) obtained by copolymerizing with OD is used. In particular, in the presence of a Group IVB transition metal catalyst system catalyst containing a specific zirconium catalyst component,
A specific random copolymer rubber (1) obtained by copolymerizing ethylene, α-olefin and MOD is preferably used. Details of the method for producing the random copolymer rubber (1) will be described later.

Even when an MOD is copolymerized with an α-olefin such as ethylene and propylene in the presence of a vanadium catalyst or a titanium catalyst which has been conventionally used in the production of EPDM, the activity thereof is extremely lowered. However, these components could not be industrially copolymerized. Therefore, the inventors of the present invention conducted extensive studies on the catalyst, and if these components were copolymerized using a Group IVB transition metal catalyst-based catalyst containing a specific zirconium catalyst component, these components would be polymerized well. In the present invention, by using a specific Group IVB transition metal catalyst system catalyst, α-olefins such as ethylene and propylene and M
It was decided to copolymerize with OD.

The present inventors have also studied a cocatalyst, and copolymerized α-olefins such as ethylene and propylene with MOD in a catalyst system in which an organoaluminum oxy compound is combined with a zirconium catalyst as a cocatalyst. As a result, they have found that it is possible to control the structure of a polymer having excellent co-vulcanization properties with a conjugated diene rubber, and have found the optimum quality of the polymer.

That is, the random copolymer rubber (1) used in the present invention has the following composition and characteristics. (I) The random copolymer rubber (1) has a molar ratio of ethylene and α-olefin (ethylene / α-olefin) of 40/60 to 90/10, preferably 55/45.
~ 85/15, more preferably 65 / 35-80 / 2
It is in the range of 0. When a random copolymer rubber (1) having a molar ratio of ethylene and α-olefin (ethylene / α-olefin) in the above range is blended with a conjugated diene rubber, excellent mechanical strength and low temperature are obtained. However, a rubber composition having rubber properties can be obtained.

(Ii) The random copolymer rubber (1) has a non-conjugated diene content of 7-methyl-1,6-octadiene (hereinafter sometimes abbreviated as MOD content) of 0.4 to. It is in the range of 25 mol%, preferably 0.5 to 7 mol%, more preferably 1 to 4 mol%. When the ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber having a MOD content in the above range is used, it has excellent co-vulcanizability with a conjugated diene rubber, and EP
It is possible to obtain a rubber composition that retains the excellent heat aging resistance inherent in DM.

EPDM in which the diene component is MOD (hereinafter sometimes abbreviated as MOD-EPDM) and diene component in 5-ethylidene-2-norbornene (hereinafter referred to as ENB
EPDM (hereinafter, ENB-)
(Sometimes abbreviated as EPDM) at the same diene content, MOD-EPDM has a vulcanization rate more than twice as fast.

The V-th component containing the vanadium catalyst component
ENB-E produced using a Group B transition metal catalyst-based catalyst
Even if the PDM has a high diene content, the effect of improving the vulcanization rate is lost when the PDM content exceeds 4 mol%. On the other hand, MOD-EPDM produced by using a Group IVB transition metal catalyst-based catalyst containing a specific zirconium catalyst component
Can accelerate the vulcanization rate in proportion to the diene content until the diene content becomes 7 mol%.

The V-th component containing a vanadium catalyst component
ENB-E produced using a Group B transition metal catalyst-based catalyst
As PDM increases its diene content in order to accelerate the vulcanization rate, the low temperature flexibility deteriorates proportionately. On the other hand, MOD-EPDM produced by using a Group IVB transition metal catalyst-based catalyst containing a specific zirconium catalyst component
Has excellent low temperature flexibility regardless of its diene content.

(Iii) Furthermore, the random copolymer rubber (1) has an intrinsic viscosity [η] measured in decalin at 135 ° C. of 0.1 dl / g <[η] <8 dl / g, preferably 0.1. It is in the range represented by 2 dl / g <[η] <6 dl / g, and more preferably 0.3 dl / g <[η] <5 dl / g. When the random copolymer rubber (1) having an intrinsic viscosity [η] in the above range is used, the blendability with the conjugated diene rubber is good and the conjugated diene rubber has excellent mechanical strength characteristics. In addition, it is possible to obtain a rubber composition capable of imparting a vulcanized rubber having excellent heat resistance and weather resistance.

(Iv) Further, this random copolymer rubber (1) has Tα of Tαβ in ¹³ C-NMR spectrum.
The strength ratio D to αα (= Tαβ / Tαα) is 0.5 or less, and the preferable strength ratio D differs depending on the type of α-olefin constituting the random copolymer rubber (1).

The above strength ratio D of the random copolymer rubber (1) used in the present invention is ¹³ C according to the following method.
-Calculate based on the measurement result of the NMR spectrum. That is, the above ¹³ C-NMR is based on JEO manufactured by JEOL Ltd.
Using an L-GX270 NMR measuring apparatus, using a mixed solution of hexachlorobutadiene / d ₆ -benzene = 2/1 volume ratio with a polymer concentration of 5% by weight, d at 67.8 MHz and 25 ° C.
₆ -Benzene (128 ppm) is used as a standard.

The analysis of the NMR spectrum was conducted by Lindemann Adams (Analysis Chemistry 43 , p1245 (197).
1)), JCRandall (Review Macromolecular Chemistry
Physics, C29, 201 (1989)).

Here, regarding the strength ratio D, ethylene
A propylene / 7-methyl-1,6-octadiene copolymer rubber will be described as an example. In this case, in the ¹³ C-NMR spectrum, the peak appearing at 45 to 46 ppm is assigned to Tαα, and the peak appearing at 32 to 33 ppm is assigned to Tαβ, and the integrated value of each peak portion is determined to obtain the intensity ratio D above. To calculate.

The intensity ratio D thus obtained is generally the ratio of the 1,1 addition reaction of propylene followed by the 2,1 addition reaction, or the 1,2 addition reaction of propylene, followed by the 1,2 addition reaction. It is considered to be a measure of the rate at which an addition reaction occurs. Therefore, the larger the strength ratio D value, the more irregular the bonding direction of the monomer copolymerizable with ethylene. On the contrary, the smaller the D value is, the more regular the bonding direction is. The higher the regularity, the easier the molecular chains are to aggregate, and the better the physical properties such as strength may be. Therefore, in the present invention, the smaller the D value is, the more preferable.

In the present invention, the intensity ratio D (= Tαβ / Tαα) of Tαβ to Tαα is 0.5 or less, preferably 0.1 or less, more preferably 0.05 or less. By copolymerizing ethylene, propylene and 7-methyl-1,6-octadiene in the presence of a Group IVB transition metal catalyst system catalyst containing a Group IVB transition metal catalyst component such as specific zirconium, It is possible to obtain an ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber having a strength ratio D of 0.5 or less.

However, even if ethylene, propylene and 7-methyl-1,6-octadiene are copolymerized in the presence of a Group VB transition metal catalyst system catalyst containing a vanadium catalyst component, the above strength ratio D It is not possible to obtain an ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber having a ratio of 0.5 or less. However, it is assumed that this Group VB transition metal catalyst-based catalyst does not contain a Group IVB transition metal catalyst component containing a ligand having a cyclopentadienyl skeleton.

The same applies to α-olefins other than propylene. (V) Further, this random copolymer rubber (1) is ¹³ C
The B value calculated from the NMR spectrum and the following formula is 1.00 to 1.50, preferably 1.02 to 1.
50, more preferably 1.02 to 1.45, particularly preferably 1.02 to 1.40.

B = P _OE / (2P _E · P _O ) In the above formula, P _E is a random copolymer rubber (1)
Is the content mole fraction of the ethylene component excluding the ethylene units derived from the 7-methyl-1,6-octadiene component, and P _O is the content of the α-olefin component in the random copolymer rubber (1) It is a mole fraction, and P _OE is the ratio of the number of α-olefin / ethylene chains to the total number of dyad chains in the random copolymer rubber (1).

This B value depends on each monomer in the copolymer chain.
It is an index that shows the distribution state of Mar.
romolecules, 15, 353 (1982)), J.Ray (Macromolecule
s, 10,773 (1977)) based on the above report,
Defined P_E , P_O And P _OEBy asking for
The B value is calculated from the above formula.

It is shown that the larger the above B value, the shorter the block-like chain of ethylene or α-olefin, the more uniform distribution of ethylene and α-olefin, and the narrower composition distribution of the copolymer. Also, the smaller the B value, the wider the composition distribution of the copolymer, and when such a copolymer is to be used after being vulcanized, it has a higher strength than a copolymer having a narrow composition distribution. It is not preferable because sufficient physical properties are not expressed.

Copolymerization of ethylene, α-olefin and 7-methyl-1,6-octadiene in the presence of a Group IVB transition metal catalyst system catalyst containing a specific Group IVB transition metal catalyst component. Therefore, the B value is 1.00
1.50 is ethylene / α-olefin / 7-methyl-
A 1,6-octadiene copolymer rubber can be obtained.

However, in the presence of a Group IVB transition metal catalyst-based catalyst containing a titanium catalyst component, ethylene and α
-Ethylene / α- having a B value in the above range even when an olefin and 7-methyl-1,6-octadiene are copolymerized
It is not possible to obtain an olefin / 7-methyl-1,6-octadiene copolymer rubber. However, this Group IVB transition metal catalyst-based catalyst does not include a Group IVB transition metal catalyst component containing a ligand having a cyclopentadienyl skeleton.

(Vi) Furthermore, the random copolymer rubber (1) has a glass transition temperature Tg determined by DSC (differential scanning calorimeter) of −53 ° C. or lower. When the random copolymer rubber (1) having a glass transition temperature Tg of −53 ° C. or lower is used, a rubber composition capable of imparting a vulcanized rubber excellent in low temperature flexibility can be obtained.

Random copolymer rubber (1) as described above
Is a particular zirconium, for example, as described above,
Group IVB containing a Group IVB transition metal catalyst component such as titanium
It is produced by copolymerizing ethylene, α-olefin, and MOD in the presence of a group-transition metal catalyst-based catalyst.

A preferred example of the Group IVB transition metal catalyst-based catalyst is a Group IVB transition metal catalyst-based catalyst comprising a zirconium compound containing a ligand having a cyclopentadienyl skeleton and an organoaluminum oxy compound (b). And a zirconium compound containing a ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound (b) and an organoaluminum compound (c).
Group IVB transition metal catalyst-based catalysts. In the present invention, the latter group IVB transition metal catalyst-based catalyst is particularly preferably used.

Examples of the Group IVB transition metal compound (a) containing a ligand having a cyclopentadienyl skeleton used in the present invention include Group IVB transition metal compounds represented by the following general formula [I]. It can be illustrated.

ML _X ... [I] In the above general formula [I], M is a Group IVB transition metal,
Zirconium is preferable, L is a ligand that coordinates with a Group IVB transition metal, and at least one L is a ligand having a cyclopentadienyl skeleton, and a cyclopentadienyl skeleton is included. L other than the ligand having is a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group, an aryloxy group, a halogen atom, a trialkylsilyl group, SO ₃
R (wherein R is a hydrocarbon group having 1 to 8 carbon atoms which may have a substituent such as halogen) or a hydrogen atom, and x is the valence of zirconium.

Specific examples of the ligand having a cyclopentadienyl skeleton include a cyclopentadienyl group; a methylcyclopentadienyl group, a dimethylcyclopentadienyl group, a trimethylcyclopentadienyl group, and tetramethyl. Cyclopentadienyl group, pentamethylcyclopentadienyl group, ethylcyclopentadienyl group, methylethylcyclopentadienyl group, propylcyclopentadienyl group, methylpropylcyclopentadienyl group,
Alkyl-substituted cyclopentadienyl groups such as butylcyclopentadienyl group, methylbutylcyclopentadienyl group, hexylcyclopentadienyl group; indenyl group;
4,5,6,7-tetrahydroindenyl group; fluorenyl group and the like.

These groups may be substituted with a halogen atom, a trialkylsilyl group or the like. Of these ligands that coordinate to zirconium, an alkyl-substituted cyclopentadienyl group is particularly preferable.

The zirconium compound represented by the general formula [I] has a cyclopentadienyl skeleton-containing group 2
In the case of containing more than one, the group having two cyclopentadienyl skeletons is an alkylene group such as ethylene or propylene, a substituted alkylene group such as isopropylidene or diphenylmethylene, a silylene group, or a dimethylsilylene group, a diphenylsilylene group, It may be bonded via a substituted silylene group such as a methylphenylsilylene group.

As the ligand other than the ligand having a cyclopentadienyl skeleton, as described above, a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group, an aryloxy group, a halogen atom, a trialkylsilyl group. Group, SO ₃ R
(However, R is a hydrocarbon group having 1 to 8 carbon atoms which may have a substituent such as halogen.) Or a hydrogen atom, and specifically, the following groups or Atoms.

Examples of the hydrocarbon group having 1 to 12 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group and pentyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group. Group;
Examples thereof include aryl groups such as phenyl group and tolyl group; and aralkyl groups such as benzyl group and neophyll group.

As the above alkoxy group, a methoxy group,
Examples thereof include an ethoxy group and a butoxy group. Examples of the aryloxy group include a phenoxy group.

Examples of the halogen atom include atoms such as fluorine, chlorine, bromine and iodine. SO above
Examples of the ligand represented by ₃ R include a p-toluenesulfonato group, a methanesulfonato group, and a trifluoromethanesulfonato group.

The Group IVB transition metal compound represented by the above general formula [I] is, for example, a zirconium compound having a valence of 4 and more specifically represented by the following general formula [II].

R ¹ _a R ² _b R ³ _c R ⁴ _d M ··· [II] (In the formula [II], M is zirconium and R ¹ is a group having a cyclopentadienyl skeleton. R ² , R ³ and R ⁴ are a group having a cyclopentadienyl skeleton, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a halogen atom, a trialkylsilyl group, SO ₃ R or a hydrogen atom,
a is an integer of 1 or more, and a + b + c + d = 4. ) In the present invention, in the above general formula [II], R
^A zirconium compound in which one of ² , R ³ and R ⁴ is a group having a cyclopentadienyl skeleton, for example,
A zirconium compound in which R ¹ and R ² are groups having a cyclopentadienyl skeleton is preferably used. Groups having these cyclopentadienyl skeletons include alkylene groups such as ethylene and propylene, substituted alkylene groups such as diphenylmethylene, alkylidene groups such as isopropylidene, silylene groups, or dimethylsilylene, diphenylsilylene, methylphenylsilylene, and the like. It may be bonded via a substituted silylene group or the like. R ³ and R ⁴ are a group having a cyclopentadienyl skeleton, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a halogen atom, a trialkylsilyl group, SO ₃ R or hydrogen. Is an atom.

The zirconium compound represented by the above general formula [II] will be specifically exemplified below. Bis (indenyl) zirconium dichloride, bis (indenyl) zirconium dibromide, bis (indenyl) zirconium bis (p-toluenesulfonato) bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, bis (fluorenyl) zirconium Dichloride, ethylenebis (indenyl) zirconium dichloride, ethylenebis (indenyl) zirconium dibromide, ethylenebis (indenyl) dimethylzirconium, ethylenebis (indenyl) diphenylzirconium, ethylenebis (indenyl) methylzirconium monochloride, ethylenebis (indenyl) Zirconium bis (methane sulfonate), ethylene bis (indenyl) zirconium bis (p-toluene sulfonate), ethylene bis (indenyl) zirconium Umbis (trifluoromethanesulfonato), ethylenebis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-methylcyclopenta) Dienyl) zirconium dichloride, dimethylsilylenebis (cyclopentadienyl) zirconium dichloride, dimethylsilylenebis (methylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (trimethylcyclo) Pentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (indenyl)
Zirconium bis (trifluoromethane sulfonate),
Dimethyl silylene bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, dimethyl silylene (cyclopentadienyl-fluorenyl) zirconium dichloride, diphenyl silylene bis (indenyl) zirconium dichloride, methylphenyl silylene bis (indenyl) zirconium dichloride , Bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dibromide, bis (cyclopentadienyl) methylzirconium monochloride, bis (cyclopentadienyl) ethylzirconium monochloride, bis (cyclopenta Dienyl) cyclohexyl zirconium monochloride, bis (cyclopentadienyl) phenyl zirconium monochloride, bis (cyclopentadienyl) benzyl Zirconium monochloride,
Bis (cyclopentadienyl) zirconium monochloride monohydride, bis (cyclopentadienyl) methylzirconium monohydride, bis (cyclopentadienyl) dimethylzirconium, bis (cyclopentadienyl) diphenylzirconium, bis (cyclopentadienyl) (Enyl) dibenzyl zirconium, bis (cyclopentadienyl) zirconium methoxy chloride, bis (cyclopentadienyl) zirconium ethoxy chloride, bis (cyclopentadienyl) zirconium bis (methanesulfonato), bis (cyclopentadienyl)
Zirconium bis (p-toluenesulfonato), bis (cyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (methylcyclopentadienyl) zirconium dichloride, bis (dimethylcyclopentadienyl) zirconium dichloride, bis ( Dimethylcyclopentadienyl) zirconium ethoxy chloride, bis (dimethylcyclopentadienyl) zirconium bis (trifluoromethanesulfonato), bis (ethylcyclopentadienyl) zirconium dichloride, bis (methylethylcyclopentadienyl) zirconium dichloride, Bis (propylcyclopentadienyl) zirconium dichloride, bis (methylpropylcyclopentadienyl) zirconium dichloride, bis (butylcyclopentadiene) Le) zirconium dichloride, bis (methyl-butylcyclopentadienyl) zirconium dichloride, bis (methyl-butylcyclopentadienyl)
Zirconium bis (methanesulfonato), bis (trimethylcyclopentadienyl) zirconium dichloride,
Bis (tetramethylcyclopentadienyl) zirconium dichloride, bis (pentamethylcyclopentadienyl) zirconium dichloride, bis (hexylcyclopentadienyl) zirconium dichloride, bis (trimethylsilylcyclopentadienyl) zirconium dichloride.

In the above example, the di-substituted cyclopentadienyl ring includes 1,2- and 1,3-substituted compounds,
Tri-substitutions include 1,2,3- and 1,2,4-substitutions. Alkyl groups such as propyl and butyl are n-, i-, sec-, te
Includes isomers such as rt-.

In the present invention, the above zirconium compounds can be used alone or in combination of two or more kinds. The organoaluminum oxy compound (b) used in the present invention may be a conventionally known aluminoxane, or is a benzene-insoluble organoaluminum oxy compound as exemplified in JP-A-2-78687. May be.

The conventionally known aluminoxane can be produced, for example, by the following method. (1) Compounds containing adsorbed water or salts containing water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, ceric chloride hydrate, etc. A method of recovering a hydrocarbon solution by adding an organoaluminum compound such as trialkylaluminum to the hydrocarbon medium suspension and reacting the same. (2) A method in which water, ice or steam is directly applied to an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, ethyl ether or tetrahydrofuran to recover it as a hydrocarbon solution. (3) A method of reacting an organoaluminum compound such as trialkylaluminum with an organotin oxide such as dimethyltin oxide or dibutyltin oxide in a medium such as decane, benzene, or toluene.

The aluminoxane may contain a small amount of organic metal component. Further, the solvent or the unreacted organoaluminum compound may be removed by distillation from the recovered aluminoxane solution, and then redissolved in the solvent.

Specific examples of the organoaluminum compound used in the production of aluminoxane include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, trisec. -Butyl aluminum, tri-tert-butyl aluminum, tripentyl aluminum, trihexyl aluminum, trioctyl aluminum, tridecyl aluminum and other trialkyl aluminums; tricyclohexyl aluminum, tricyclooctyl aluminum and other tricycloalkyl aluminums; dimethyl aluminum chloride, Diethyl aluminum chloride,
Dialkyl aluminum halides such as diethyl aluminum bromide and diisobutyl aluminum chloride; Dialkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride; Dialkyl aluminum alkoxides such as dimethyl aluminum methoxide and diethyl aluminum ethoxide; Dialkyl aluminum aryloxy such as diethyl aluminum phenoxide Do and the like.

Of these, trialkylaluminum and tricycloalkylaluminum are particularly preferable.
In addition, as the organoaluminum compound used in the production of aluminoxane, isoprenylaluminum represented by the following general formula [III] can also be used.

(I-C ₄ H ₉ ) _x Al _y (C ₅ H ₁₀ ) _z ... [III] (where x, y and z are positive numbers, and z ≧ 2x The above organoaluminum compounds are used alone or in combination.

As the solvent used in the production of the aluminoxane as described above, aromatic hydrocarbons such as benzene, toluene, xylene, cumene and cymene, pentane,
Hexane, heptane, octane, decane, dodecane, hexadecane, octadecane and other aliphatic hydrocarbons, cyclopentane, cyclohexane, cyclooctane, alicyclic hydrocarbons such as methylcyclopentane, petroleum fractions such as gasoline, kerosene, and light oil, Alternatively, the above aromatic hydrocarbons, aliphatic hydrocarbons, alicyclic hydrocarbon halides, among others,
Examples include hydrocarbon solvents such as chlorinated compounds and brominated compounds.

In addition, ethers such as ethyl ether and tetrahydrofuran can be used. Of these solvents, aromatic hydrocarbons are particularly preferable. Examples of the organoaluminum compound (c) used in the present invention include the organoaluminum compound represented by the following general formula [IV].

R ⁵ _n AlX _3-n ... [IV] (In the formula, R ⁵ is a hydrocarbon group having 1 to 12 carbon atoms, X is a halogen atom or a hydrogen atom, and n Is 1
It is 3. ) In the above formula [IV], R ⁵ is a hydrocarbon group having 1 to 12 carbon atoms, such as an alkyl group, a cycloalkyl group or an aryl group, and specifically, a methyl group, an ethyl group, n -Propyl group, isopropyl group, isobutyl group, pentyl group, hexyl group, octyl group, cyclopentyl group, cyclohexyl group, phenyl group, tolyl group and the like.

Specific examples of such an organoaluminum compound include the following compounds. Trialkylaluminums such as trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, trioctylaluminum, tri2-ethylhexylaluminum; alkenylaluminums such as isoprenylaluminum; dimethylaluminium chloride, diethylaluminum chloride, diisopropylaluminum chloride, Dialkyl aluminum halides such as diisobutyl aluminum chloride and dimethyl aluminum bromide; alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, ethyl aluminum sesquichloride, isopropyl aluminum sesquichloride, butyl aluminum sesquichloride, ethyl aluminum sesquibromide; methylaluminium Mujikurorido, ethylaluminum dichloride, isopropyl aluminum dichloride,
Alkyl aluminum dihalides such as ethyl aluminum dibromide; alkyl aluminum hydrides such as diethyl aluminum hydride and diisobutyl aluminum hydride.

As the organoaluminum compound (c), a compound represented by the following formula [V] can also be used. R ⁵ _n AlY _3-n ... [V] (In the formula, R ⁵ is the same as above, Y is an —OR ⁶ group,
OSiR ⁷ ₃ group, -OAlR ⁸ ₂ group, -NR ⁹ ₂ group, -SiR
¹⁰ ₃ groups or —N (R ¹¹ ) AlR ¹² ₂ groups, and n is 1
Is 2, and R ⁶ , R ⁷ , R ⁸ and R ¹² are methyl groups,
An ethyl group, an isopropyl group, an isobutyl group, a cyclohexyl group, a phenyl group and the like, R ⁹ is hydrogen, a methyl group,
It is an ethyl group, an isopropyl group, a phenyl group, a trimethylsilyl group or the like, and R ¹⁰ and R ¹¹ are a methyl group, an ethyl group or the like. ) Specific examples of such an organoaluminum compound include the following compounds.

(I) Compounds represented by R ⁵ _n Al (OR ⁶ ) _3-n , such as dimethyl aluminum methoxide, diethyl aluminum ethoxide, diisobutyl aluminum methoxide and the like.

(Ii) a compound represented by R ⁵ _n Al (OSiR ⁷ ₃ ) _3-n , for example, (C ₂ H ₅ ) ₂ Al (OSi (CH
_{3) 3), (iso-} C 4 H 9) 2 Al (OSi (CH 3) 3),
_{(Iso-C 4 H 9)} 2 Al (OSi (C 2 H 5) 3) and the like.

(Iii) a compound represented by R ⁵ _n Al (OAlR ⁸ ₂ ) _3-n , for example (C ₂ H ₅ ) ₂ Al (OAl
_{(C 2 H 5) 2)} , (iso-C 4 H 9) 2 Al (OAl (iso-C
₄ H ₉ ) ₂ ) etc.

(Iv) A compound represented by R ⁵ _n Al (NR ⁹ ₂ ) _3-n , for example, (CH ₃ ) ₂ Al (N (C
_{2 H 5) 2), (} C 2 H 5) 2 Al (NH (CH 3)), (C
_{H 3) 2 Al (NH (} C 2 H 5)), (C 2 H 5) 2 Al [N
_{(Si (CH 3) 3)} 2], (iso-C 4 H 9) 2 Al [N (Si
(CH ₃ ) ₃ ) ₂ ] etc.

(V) A compound represented by R ⁵ _n Al (SiR ¹⁰ ₃ ) _3-n , for example, (iso-C ₄ H ₉ ) ₂ Al (Si (CH
₃ ) ₃ ) etc.

[0078]

[Chemical 2]

Among the organoaluminum compounds represented by the above general formulas [IV] and [V], R ⁵ ₃ Al and R ⁵ _n Al
A preferred example is an organoaluminum compound represented by (OR ⁶ ) _3-n , R ⁵ _n Al (OAlR ⁸ ₂ ) _3-n , wherein R ⁵ is an isoalkyl group and n = 2. Is particularly preferable. These organoaluminum compounds may be used alone or in combination of two or more.

The Group IVB transition metal catalyst-based catalyst containing the specific Group IVB transition metal catalyst component used in the present invention is
From a Group IVB transition metal compound (a) such as zirconium containing a ligand having a cyclopentadienyl skeleton as described above, an organoaluminum oxy compound (b), and optionally an organoaluminum compound (c) It is formed.

In the present invention, the zirconium compound as the Group IVB transition metal compound (a) is usually converted into zirconium atom per 1 liter of the polymerization volume, and is usually about 0.
00005-0.1 mmol, preferably about 0.000
Used in an amount of 1-0.05 mmol.

Further, in the organoaluminum oxy compound (b), the aluminum atom in the organoaluminum oxy compound (b) is
Usually about 1 to 10,000 moles, preferably 10 to 5,
It is used in an amount such that it is 000 mol.

Further, the organoaluminum compound (c)
Is usually used in an amount of about 0 to 200 mol, preferably about 0 to 100 mol, per 1 mol of aluminum atom in the organoaluminum oxy compound (b).

In the present invention, when the ethylene, the α-olefin and the 7-methyl-1,6-octadiene are copolymerized, the above-mentioned Group IVB transition metal constituting the above-mentioned Group IVB transition metal catalyst system catalyst is used. The compound (a), the organoaluminum oxy compound (b), and further the organoaluminum compound (c) may be separately fed to the polymerization reactor, or the above-mentioned first may be added before the copolymerization reaction. IV
A Group IVB transition metal catalyst-based catalyst containing a Group B transition metal catalyst component may be prepared.

FIG. 1 shows a process for preparing a Group IVB transition metal catalyst-based catalyst containing a zirconium catalyst component used in the production of the random copolymer rubber (1) used in the present invention.

Specific examples of the inert hydrocarbon medium used for preparing the Group IVB transition metal catalyst-based catalyst containing the Group IVB transition metal catalyst component such as zirconium include:
Aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, kerosene;
Alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethylene chloride, chlorobenzene and dichloromethane, and mixtures thereof. it can.

The mixing temperature for mixing and contacting the Group IVB transition metal compound (a), the organoaluminum oxy compound (b) and the organoaluminum compound (c) is usually -100 to 200 ° C., preferably -70. ~ 100 ° C
It is desirable that the range is.

The above copolymerization is usually carried out at a temperature of -20 to 200.
° C, preferably 0 to 150 ° C, particularly preferably 20 to 1
At 20 ° C., the pressure is usually atmospheric pressure to 100 kg / cm ² ,
Preferably atmospheric pressure to 50 kg / cm ^2, particularly preferably carried out under conditions of atmospheric pressure 30 kg / cm ^2.

The molecular weight of the random copolymer rubber (1) can be adjusted by changing the polymerization conditions such as the polymerization temperature, and can be adjusted by controlling the amount of hydrogen (molecular weight modifier) used. You can also do it.

The polymerization can be carried out by any of batch method, semi-continuous method and continuous method, but continuous method is preferred. Further, the polymerization can be carried out in two or more stages by changing the reaction conditions.

The polymer produced immediately after the polymerization is recovered from the polymerization solution and dried by a conventionally known separation / recovery method to obtain a solid random copolymer rubber (1). In the present invention, the random copolymer rubber (1) is 5 to 95 parts by weight, preferably 10 parts by weight, based on 100 parts by weight of the total amount of the random copolymer rubber (1) and the conjugated diene rubber (2). Used in an amount of ~ 60 parts by weight.

Conjugated diene rubber (2) The conjugated diene rubber (2) used in the present invention is a rubber composed of a homopolymer of a conjugated diene compound or a copolymer mainly composed of a conjugated diene compound, It is roughly divided into natural rubber and synthetic rubber.

Specific examples of the conjugated diene compound include butadiene, isoprene and chloroprene. In addition, vinyl compounds such as styrene and acrylonitrile are used as the compound that can be copolymerized with the conjugated diene compound.

Specific examples of the conjugated diene rubber (2) preferably used in the present invention include natural rubber (NR),
Isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), acrylonitrile
-Butadiene rubber (NBR), chloroprene rubber (C
R) and the like.

Among them, the isoprene type rubber having the best balance of mechanical strength, that is, natural rubber (NR),
Isoprene rubber (IR) is preferably used. In the present invention, the conjugated diene rubber (2) is the random copolymer rubber (1) and the conjugated diene rubber (2).
It is used in an amount of 5 to 95 parts by weight, preferably 40 to 90 parts by weight, based on 100 parts by weight of total.

Rubber composition and vulcanized product thereof Ethylene / α-olefin / 7-methyl-according to the present invention
As described above, the 1,6-octadiene copolymer rubber composition is the random copolymer rubber (1), that is, the ethylene / α-olefin / 7-methyl-1,6-octadiene copolymer rubber, and the conjugate. It is composed of a diene rubber (2).

In addition to these components, the rubber composition according to the present invention contains SRF, GPF, FEF, HAF, ISA.
Carbon black such as F, SAF, FT, MT, rubber reinforcing agent such as finely divided silicic acid, and light calcium carbonate,
Fillers such as ground calcium carbonate, talc and clay may be added. The types and blending amounts of these rubber reinforcing agents and fillers can be appropriately selected according to their applications,
The compounding amount thereof is usually 300 parts by weight at maximum, preferably 200 parts by weight, based on 100 parts by weight of the total amount of the random copolymer rubber (1) and the conjugated diene rubber (2).

The rubber composition according to the present invention can be used as it is unvulcanized, but it can exhibit its properties most when used as a vulcanized rubber. That is, the random copolymer rubber (1) constituting the rubber composition according to the present invention has a function of improving properties such as weather resistance and ozone resistance of the vulcanized rubber, and the diene rubber (2). Has a function of improving properties such as strength of the vulcanized rubber, and therefore, to obtain a vulcanized rubber excellent in strength, weather resistance, ozone resistance and dynamic fatigue resistance from the rubber composition according to the present invention. You can

In producing a vulcanized rubber from the rubber composition according to the present invention, depending on the intended use of the vulcanized rubber and the performance based thereon, in addition to the above components (1) and (2), rubber reinforcement Types and amounts of vulcanizing agents, fillers, softeners, vulcanizing agents, vulcanization accelerators, vulcanization aids, etc. The process to be performed is appropriately selected.

As the above-mentioned softening agent, a softening agent generally used for rubber is used. Specifically, petroleum-based softening agents such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, petroleum jelly; coal. Coal tar type softeners such as tar and coal tar pitch; Fat oil type softeners such as castor oil, linseed oil, rapeseed oil and coconut oil;
Tall oil; sub; waxes such as beeswax, carnauba wax, lanolin; fatty acids and fatty acid salts such as ricinoleic acid, palmitic acid, barium stearate, calcium stearate, zinc laurate; petroleum resin, atactic polypropylene, coumarone indene resin Synthetic polymer substances such as are used. Of these, petroleum-based softeners are preferably used, and process oils are particularly preferably used.

The blending amount of the softening agent is 150 parts by weight at the maximum, preferably 100 parts by weight, based on 100 parts by weight of the total amount of the above components (1) and (2). When the vulcanized rubber according to the present invention is produced, the following sulfur compounds are used as a vulcanizing agent.

Specific examples of the sulfur compound include sulfur, sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, and selenium dimethyldithiocarbamate. Of these, sulfur is preferably used. To be

The above sulfur compound is used in an amount of 0.1 to 5 relative to 100 parts by weight of the total amount of the above components (1) and (2).
It is used in an amount of 0.5 part by weight, preferably 0.5 to 3 parts by weight. When a sulfur compound is used as a vulcanizing agent when producing a vulcanized rubber from the rubber composition according to the present invention, it is preferable to use a vulcanization accelerator together.

Specific examples of vulcanization accelerators include N-cyclohexyl-2-benzothiazole-sulfenamide, N
-Oxydiethylene-2-benzothiazole-sulfenamide, N, N-diisopropyl-2-benzothiazole-sulfenamide, 2-mercaptobenzothiazole, 2-
Thiazole compounds such as (2,4-dinitrophenyl) mercaptobenzothiazole, 2- (2,6-diethyl-4-morpholinothio) benzothiazole, dibenzothiazyl-disulfide; diphenylguanidine, triphenylguanidine, diorsotolyl Guanidine compounds such as guanidine, orthotolyl by guanide, and diphenylguanidine phthalate; acetaldehyde-aniline reaction products, butyraldehyde-aniline condensates, hexamethylenetetramine, acetaldehyde-ammonia reaction products, etc. aldehyde-amine or aldehyde-ammonia systems Compounds; 2-mercaptoimidazoline and other imidazoline compounds; thiocarbanilide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea and other thioureas Compounds; tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide, and other thiuram compounds; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate,
Zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate,
Dithioate compounds such as selenium dimethyldithiocarbamate and tellurium diethyldithiocarbamate; Xanthate compounds such as zinc dibutylxanthate; Others,
A compound such as zinc white is used.

The vulcanization accelerator is used in a proportion of 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight, based on 100 parts by weight of the total amount of the components (1) and (2). To be The unvulcanized compounded rubber is prepared by the following method. That is, using a mixer such as a Banbury mixer, the above components (1) and (2) and further a softening agent are kneaded at a temperature of 80 to 150 ° C. for 3 to 10 minutes, and then,
A roll such as an open roll is used to additionally mix a vulcanizing agent and, if necessary, a vulcanization accelerator or a vulcanization aid, and the mixture is kneaded at a roll temperature of 40 to 60 ° C for 5 to 30 minutes, and then a kneaded product An extruded, ribbon-shaped or sheet-shaped compounded rubber is prepared.

The compounded rubber thus prepared is molded into an intended shape by an extruder, a calender roll, or a press. Simultaneously with molding or by introducing the molded product into a vulcanization tank, the compounded rubber at 120 to 270 ° C. Heat at a temperature for 1 to 30 minutes to obtain a vulcanized rubber. When performing such vulcanization, a mold may or may not be used. When a mold is not used, the molding and vulcanization steps are usually carried out continuously.

[0107]

Industrial Applicability The random copolymer rubber composed of ethylene, α-olefin and 7-methyl-1,6-octadiene used in the present invention has a molar ratio of ethylene and α-olefin of 7-methyl-1. , 6-octadiene content, intrinsic viscosity [η], Tαβ and T in ¹³ C-NMR spectrum
Since the strength ratio D with αα, the B value, and the glass transition temperature Tg are in the specific ranges, they have high stereoregularity, a narrow composition distribution, and excellent low-temperature flexibility, and also have a very good co-functionality with conjugated diene rubbers. It exhibits vulcanizability.

Further, this random copolymer rubber is excellent in properties such as weather resistance, ozone resistance and heat aging resistance. First containing a ligand having a cyclopentadienyl skeleton
Among Group IVB transition metal catalyst-based catalysts containing Group IVB transition metal catalyst components, Group IVB transition metal catalyst-based catalysts comprising a zirconium compound containing a ligand having a cyclopentadienyl skeleton and an organoaluminum oxy compound,
Alternatively, a Group IVB transition metal catalyst-based catalyst composed of such a zirconium compound, an organoaluminum oxy compound and an organoaluminum compound, particularly a random copolymer rubber obtained by using the latter catalyst, is a co-addition with a conjugated diene rubber. Extremely excellent in vulcanization.

Ethylene / α-olefins according to the present invention
Since the 7-methyl-1,6-octadiene copolymer rubber composition is composed of such a random copolymer rubber and a conjugated diene rubber, it has excellent mechanical properties originally possessed by the conjugated diene rubber. And maintain oil resistance,
It is possible to provide a vulcanized rubber excellent in low-temperature flexibility, abrasion resistance, fatigue resistance, weather resistance, ozone resistance and heat aging resistance.

Therefore, the rubber composition according to the present invention is
It is suitable for use in automobile parts such as pneumatic tire sidewalls, white sidewalls, wiper blades, and brake piston cups. In particular, the rubber composition obtained by blending the random copolymer rubber and NBR can provide a vulcanized rubber having an unprecedented balance of oil resistance, weather resistance and heat resistance. Suitable for applications such as rubber hose, rubber packing, and seal parts.

The present invention will be described below with reference to examples.
The present invention is not limited to these examples. The EPDM and vulcanized sheet evaluation test methods in Examples and Comparative Examples are as follows.

[1] Covulcanization Degree The covulcanization degree was calculated by the following formula. Co-vulcanization degree [%] = T _B (blend) × 100 / [T _B
(EPDM) × a + T _B (NR) × b] In the above formula, T _B (blend) represents the actual tensile strength of the blend material, and T _B (EPDM) is the ethylene / propylene / diene rubber (EPDM). ), T _B (NR) represents the tensile strength of natural rubber (NR), a represents the weight fraction of ethylene / propylene / diene rubber (EPDM), and b represents It represents the weight fraction of natural rubber (NR), where a + b = 1.

[2] Tensile Test JIS K 6301 (198) was prepared by punching out a vulcanized rubber sheet.
No. 3 type dumbbell test piece described in 9 years) was prepared, and the test piece was used in accordance with the method defined in the same JIS K 6301 paragraph 3, measurement temperature 25 ° C., tensile speed 500
A tensile test was conducted under conditions of mm / min, and 25% modulus (M ₂₅ ), 50% modulus (M ₅₀ ), 100% modulus (M ₁₀₀ ), 200% modulus (M ₂₀₀ ), 3
The 00% modulus (M ₃₀₀ ), the tensile stress at break T _B and the elongation at break E _B were measured.

[3] Hardness Test In the hardness test, the spring hardness H _S (JIS A hardness) was measured according to JIS K 6301 (1989).

[4] Bending Fatigue Test The bending fatigue test was carried out in accordance with ASTM D 813 using a DeMatcher-Bending tester under the conditions of a rotation speed of 300 rpm and a measurement temperature of 40 ° C., and a crack growth rate (mm / cyc).
le) was obtained and used as an index of dynamic fatigue resistance (durability).

[5] Elongation Fatigue Test (Monsanto Fatigue Test) A vulcanized rubber sheet was punched out to produce a No. 1 type dumbbell test piece described in JIS K 6301, and the test piece had a lengthwise center of 2 mm. I made a scratch. The elongation rate of each of the 20 test pieces thus obtained was 40%,
80% and 120%, measurement temperature 40 ℃, rotation speed 30
Elongation fatigue was performed under the condition of 0 rpm, and the average value of the number of times of dumbbell cutting was used as an index of dynamic fatigue resistance (durability).

[6] Ozone resistance test According to JIS K 6301, ozone concentration is 50 ppm,
The crack generation time was measured under the conditions of a measurement temperature of 40 ° C. and an elongation rate (static elongation) of 20%, and the crack generation time was used as an index of ozone resistance or weather resistance. The test period is 1
It is day 0.

[7] Low-Temperature Flexibility Low-temperature flexibility is obtained by blending with E before blending with natural rubber (NR).
The glass transition temperature Tg of the PDM alone will be evaluated,
The glass transition temperature was measured with a differential scanning calorimeter (DSC). The glass transition temperature of the natural rubber itself was also measured.

-Temperature cycle in Tg measurement by DSC The sample is heated from room temperature (25 ° C) to 20 ° C / min at a rate of 18 ° C.
After raising the temperature to 0 ° C. and maintaining it at 180 ° C. for 2 minutes, this sample was cooled to −80 ° C. at a rate of −20 ° C./min, and 2
Hold the sample at −80 ° C. for a minute, and then repeat this sample at 20 ° C. /
The temperature was raised at a rate of min to obtain the Tg of the sample.

[0120]

Reference Example 1 Using a 15-liter stainless steel polymerization vessel equipped with a stirring blade, ethylene, propylene and 7-methyl-1,6-octadiene were continuously copolymerized.

That is, first, 2.0 liters of dehydrated and purified hexane per hour was introduced into the polymerization vessel from the upper portion of the polymerization vessel, and a hexane solution of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride (concentration: 0.05 mmol /
0.2 liter / hour, hexane solution of triisobutylaluminum (concentration 17 mmol / liter) 0.3 liter / hour, hexane slurry solution of methylalumoxane (3 mg atom / liter in terms of aluminum atom). 1 liter / h, 7-methyl
A hexane solution of -1,6-octadiene (concentration: 0.25 liter / liter) was continuously supplied at 1.5 liter / hour.

Further, 180 liters of ethylene per hour and 620 liters of propylene per hour were continuously fed into the polymerization vessel from the upper portion of the polymerization vessel. This copolymerization reaction is
Performed at 50 ° C.

Then, a small amount of methanol was added to the polymerization solution extracted from the lower part of the polymerization vessel to stop the polymerization reaction,
After the copolymer was separated from the solvent by steam stripping treatment, the temperature was reduced to 100 ° C and the pressure was reduced to 100 mmHg.
It was dried for 24 hours.

With the above operation, ethylene / propylene / 7
-Methyl-1,6-octadiene copolymer 250g / h
Obtained at the speed of. The obtained copolymer was a rubber, the molar ratio of ethylene and propylene (ethylene / propylene) was 70/30, and the content of 7-methyl-1,6-octadiene was 1.9 mol%. The intrinsic viscosity [η] measured in a 135 ° C decalin solvent was 2.3 dl / g. The intensity ratio D of Tαβ to Tαα in the ¹³ C-NMR spectrum was less than 0.01, the B value was 1.12, and the glass transition temperature was -61 ° C.

[0125]

Reference Examples 2 to 5 Ethylene propylene was prepared in the same manner as in Reference Example 1 except that the copolymerization reaction was carried out under the polymerization conditions shown in Table 1 instead of the polymerization conditions of Reference Example 1. 7-methyl-1,6-octadiene copolymer rubber [hereinafter, MOD-EPDM (2), (3),
(4) and (5) may be referred to].

The properties of the resulting copolymer rubber are shown in Table 1.

[0127]

Reference Example 6 Using a 4-liter polymerization vessel equipped with a stirring blade, ethylene, propylene and 7-methyl- were continuously added.
A copolymerization reaction with 1,6-octadiene was performed.

That is, from the upper part of the polymerization vessel to the inside of the polymerization vessel,
-Methyl-1,6-octadiene in toluene (concentration 6
0 g / liter) at 1.2 liters / hour, and a toluene solution of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride as a catalyst (concentration: 0.2 mmol / liter)
0.4 liter / hr, a toluene solution of methylalumoxane (concentration 26.5 mmol / liter) 1.2 liter / hr, and toluene at a rate 1.2 liter / hr. From the bottom
The polymerization liquid in the polymerization vessel was continuously withdrawn so that the polymerization liquid was always 2 liters.

In the polymerization vessel, ethylene was supplied at 80 liters / hour and propylene was supplied at 3 hours / hour using a bubbling tube.
Feeded at a rate of 20 liters. The copolymerization reaction was carried out at a temperature of 40 ° C. by circulating hot water in a jacket attached outside the polymerization vessel.

When the copolymerization reaction was carried out under the above conditions,
A polymerization solution containing an ethylene / propylene / 7-methyl-1,6-octadiene copolymer was obtained. Then, the obtained polymerization solution was decalcified with hydrochloric acid water, toluene was distilled off, and the residue was dried under reduced pressure at 100 ° C. for 24 hours.

As described above, ethylene / propylene /
95 g / h of 7-methyl-1,6-octadiene copolymer
Obtained at the speed of. The resulting copolymer [hereinafter referred to as MOD-
EPDM (6) may be referred to as a rubber, which has a molar ratio of ethylene and propylene (ethylene / propylene) of 65/35 and a 7-methyl-1,6-octadiene content of 3.4. It was mol%, and the intrinsic viscosity [η] measured in a 135 ° C. decalin solvent was 0.3 dl / g. The intensity ratio D of Tαβ to Tαα in the ¹³ C-NMR spectrum was less than 0.01, and the B value was 1.14.

[0132]

[Table 1]

[0133]

[Table 2]

[0134]

[Reference Example 7] Using a 2 liter polymerization vessel equipped with a stirring blade, a copolymerization reaction of ethylene, propylene and 5-ethylidene-2-norbornene (ENB) was continuously carried out.

That is, from the upper part of the polymerization vessel into the polymerization vessel, E
0.5 liter / hour of a hexane solution of NB (concentration 7.1 g / liter), 0.5 liter / hour of a hexane solution of VO (OC ₂ H ₅ ) Cl ₂ as a catalyst (concentration 0.8 mmol / liter), ethyl A solution of aluminum sesquichloride [Al (C ₂ H ₅ ) _1.5 Cl _1.5 ] in hexane (concentration: 8.0 mmol / l) was supplied at a rate of 0.5 liter per hour, and hexane was supplied at a rate of 0.5 liter per hour. Then, the polymerization liquid in the polymerization vessel was continuously withdrawn from the lower portion of the polymerization vessel so as to be always 1 liter.

Further, ethylene was fed into the polymerization vessel at a rate of 120 liters per hour, propylene was supplied at a rate of 180 liters per hour, and hydrogen was supplied at a rate of 15 liters per hour using a bubbling tube.

The copolymerization reaction was carried out at a temperature of 30 ° C. by circulating a refrigerant in a jacket attached to the outside of the polymerization vessel. When the copolymerization reaction was carried out under the above conditions, a polymerization solution containing an ethylene / propylene / 5-ethylidene-2-norbornene copolymer was obtained.

Then, the obtained polymerization solution was decalcified with hydrochloric acid water, a large amount of methanol was added thereto to precipitate a polymer, and the polymer was dried under reduced pressure at 100 ° C. for 24 hours. As described above, ethylene / propylene-5-ethylidene-2-
Norbornene copolymer was obtained at a rate of 64.8 g / h.

The obtained copolymer [hereinafter, referred to as ENB-EPD
M (1) may be referred to as a rubber, and is a rubber having a molar ratio of ethylene and propylene (ethylene / propylene).
Is 68/32, the ENB content is 1.8 mol%, and the intrinsic viscosity [η] measured in a solvent of decalin at 135 ° C.
Was 2.2 dl / g. The intensity ratio D of Tαβ to Tαα in the ¹³ C-NMR spectrum was 1.
It was 4.

[0140]

Reference Examples 8 and 9 Ethylene propylene was prepared in the same manner as in Reference Example 7 except that the copolymerization reaction was carried out under the polymerization conditions shown in Table 2 instead of the polymerization conditions of Reference Example 7. A 5-ethylidene-2-norbornene copolymer rubber [hereinafter sometimes referred to as ENB-EPDM (2) and (3), respectively] was obtained.

The properties of the resulting copolymer rubber are shown in Table 2.

[0142]

[Reference Example 10] Using a 2-liter polymerization vessel equipped with a stirring blade, ethylene, propylene and 7-methyl were continuously added.
A copolymerization reaction with -1,6-octadiene was performed.

That is, from the upper part of the polymerization vessel to the inside of the polymerization vessel,
-Methyl-1,6-octadiene in hexane (concentration 3
6 g / l) 0.5 l / h, V as catalyst
A hexane solution of O (OC ₂ H ₅ ) Cl ₂ (concentration 8 mmol / liter) is 0.5 liter / hour, and a hexane solution of ethylaluminum sesquichloride [Al (C ₂ H ₅ ) _1.5 Cl _1.5 ] (concentration 64 mmol / liter) Liter) 0.5 per hour
1 liter and hexane were further supplied at a rate of 0.5 liter per hour, while the polymerization liquid in the polymerization vessel was continuously withdrawn from the lower portion of the polymerization vessel so as to be always 1 liter.

Further, ethylene was supplied at a rate of 130 liters per hour, propylene was supplied at a rate of 170 liters per hour, and hydrogen was supplied at a rate of 40 liters per hour using a bubbling tube into the polymerization vessel.

The copolymerization reaction was carried out at a temperature of 20 ° C. by circulating a refrigerant in a jacket attached to the outside of the polymerization vessel. When the copolymerization reaction was carried out under the above conditions, a polymerization solution containing an ethylene / propylene / 7-methyl-1,6-octadiene copolymer was obtained.

Next, the obtained polymerization solution was decalcified with hydrochloric acid water, a large amount of methanol was added thereto to precipitate a polymer, and the polymer was dried under reduced pressure at 100 ° C. for 24 hours. As described above, ethylene / propylene / 7-methyl-1,6-
Octadiene copolymer was obtained at a rate of 47 g / h.

The obtained copolymer [hereinafter, referred to as MOD-EPD
M (7) may be referred to as a rubber, and is a rubber having a molar ratio of ethylene and propylene (ethylene / propylene).
Was 67/33, the content of 7-methyl-1,6-octadiene was 3.5 mol%, and the intrinsic viscosity [η] measured in a solvent of decalin at 135 ° C. was 0.3 dl / g. The intensity ratio D of Tαβ to Tαα in the ¹³ C-NMR spectrum was 1.43.

[0148]

[Table 3]

[0149]

[Table 4]

[0150]

[Comparative Example 1] Natural rubber (NR) [RSS No. 1] 100
Parts by weight, zinc white 5 parts by weight, stearic acid 1 part by weight, carbon black [Asahi Carbon Co., Ltd., Asahi 60H
G] 40 parts by weight and oil [Japan Sun Oil Co., Ltd.
Manufactured by Sansen 4240] and 20 parts by weight were kneaded with a 4.3 Banbury mixer [manufactured by Kobe Steel, Ltd.]. The natural rubber was masticated using an 8-inch roll (temperature of front roll and rear roll: 65 ° C.).

To the kneaded product thus obtained, 1.5 parts by weight of sulfur and 1.0 part by weight of a vulcanization accelerator [NOXCELLER CZ, manufactured by Ouchi Shinko Chemical Industry Co., Ltd.] were added and kneaded with a roll. After that, it was dispensed into a sheet form, and was determined using a Curastometer Model 3 manufactured by Japan Synthetic Rubber Co., Ltd.
_A vulcanized sheet having a thickness of 2 mm was prepared by pressing on the basis of ₉₀ (min) (150 ° C.) under the condition of 150 ° C. × t ₉₀ (min).

The vulcanized sheet obtained was subjected to the above-mentioned physical property tests and the like according to the above-mentioned methods. The results are shown in Tables 3 and 4.

[0153]

[Comparative Example 2] In Comparative Example 1, the compounding amount of natural rubber was 7
ENB-EP of Reference Example 7 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (1) was used.

The results are shown in Table 3.

[0155]

[Comparative Example 3] In Comparative Example 1, the compounding amount of natural rubber was 7
ENB-EP of Reference Example 8 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (2) was used.

The results are shown in Table 3.

[0157]

[Example 1] In Comparative Example 1, the compounding amount of natural rubber was 7
MOD-EP of Reference Example 1 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (1) was used.

The results are shown in Table 3.

[0159]

[Example 2] In Comparative Example 1, the compounding amount of natural rubber was 7
MOD-EP of Reference Example 2 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (2) was used.

The results are shown in Table 3.

[0161]

[Example 3] In Comparative Example 1, the natural rubber content was 7
MOD-EP of Reference Example 3 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (3) was used.

The results are shown in Table 3.

[0163]

Example 4 In Comparative Example 1, the compounding amount of natural rubber was 7
MOD-EP of Reference Example 4 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (4) was used.

The results are shown in Table 3.

[0165]

[Table 5]

From Table 3, the following was found. The first containing the zirconium catalyst component used in Examples 1-4
MOD-produced using a Group IVB transition metal catalyst-based catalyst
EPDM has a remarkably higher degree of co-vulcanization with NR than ENB-EPDM produced using the Group VB transition metal catalyst-based catalyst containing the vanadium catalyst component used in Comparative Examples 2 and 3. It has been improved and is excellent in co-vulcanization with NR.

In addition, the raw rubber (MO
The low temperature flexibility of D-EPDM) is improved by about 10 ° C. as compared with the raw rubber (ENB-EPDM) in Comparative Examples 2 and 3.

Comparing Examples 1 to 4 with Comparative Examples 2 and 3, in ENB-EPDM, when ENB-EPDM having a high diene content was used to increase the vulcanization rate, low temperature flexibility was obtained. Is damaged. On the other hand, MO
In D-EPDM, the low temperature flexibility is hardly impaired even when the diene content is increased.

EPDM used in Examples 1 to 4
Has improved co-vulcanizability with NR and therefore improved fatigue resistance, and has obtained physical property values better than those of NR in Comparative Example 1.

[0170]

Comparative Example 4 In Comparative Example 1, the compounding amount of natural rubber was 8
ENB-EP of Reference Example 9 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 20 parts by weight of DM (3) was used.

The results are shown in Table 4.

[0172]

Comparative Example 5 In Comparative Example 1, the compounding amount of natural rubber was 7
ENB-EP of Reference Example 9 while changing to 5 parts by weight
Comparative Example 1 was repeated except that 25 parts by weight of DM (3) was used.

The results are shown in Table 4.

[0174]

[Comparative Example 6] In Comparative Example 1, the compounding amount of natural rubber was 7
ENB-EP of Reference Example 9 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (3) was used.

The results are shown in Table 4.

[0176]

Comparative Example 7 In Comparative Example 1, the natural rubber content was 6
ENB-EP of Reference Example 9 while changing to 5 parts by weight
Comparative Example 1 was repeated except that 35 parts by weight of DM (3) was used.

The results are shown in Table 4.

[0178]

Example 5 In Comparative Example 1, the compounding amount of natural rubber was 8
MOD-EP of Reference Example 5 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 20 parts by weight of DM (5) was used.

The results are shown in Table 4.

[0180]

Example 6 In Comparative Example 1, the compounding amount of natural rubber was 7
MOD-EP of Reference Example 5 while changing to 5 parts by weight
Comparative Example 1 was repeated except that 25 parts by weight of DM (5) was used.

The results are shown in Table 4.

[0182]

[Example 7] In Comparative Example 1, the compounding amount of natural rubber was 7
MOD-EP of Reference Example 5 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 30 parts by weight of DM (5) was used.

The results are shown in Table 4.

[0184]

[Example 8] In Comparative Example 1, the compounding amount of natural rubber was 6
MOD-EP of Reference Example 5 while changing to 5 parts by weight
Comparative Example 1 was repeated except that 35 parts by weight of DM (5) was used.

The results are shown in Table 4.

[0186]

[Example 9] In Comparative Example 1, the compounding amount of natural rubber was 8
MOD-EP of Reference Example 6 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 20 parts by weight of DM (6) was used.

The results are shown in Table 4.

[0188]

[Comparative Example 8] In Comparative Example 1, the compounding amount of natural rubber was 8
MOD-E of Reference Example 10 while changing to 0 parts by weight
Comparative Example 1 was repeated except that 20 parts by weight of PDM (7) was used.

The results are shown in Table 4.

[0190]

[Table 6]

From Table 4, the following was found. Comparative Examples 4 to 7, which have the same blend ratios as Examples 5 to 8, respectively.
Comparing with, Example 5 using MOD-EPDM
The crack growth resistance of the vulcanized rubber of No. 8 is about twice as good as that of the vulcanized rubbers of Comparative Examples 4 to 7, which means that Examples 5 to
It is shown that the MOD-EPDM used in No. 8 is excellent in co-vulcanization property with NR.

The excellent co-vulcanizability of MOD-EPDM with NR also affects ozone resistance. In Comparative Examples 4 to 7, the total amount of NR and ENB-EPDM was 100.
While the content of ENB-EPDM was 30 parts by weight with respect to parts by weight, the effect of suppressing cracking appeared, while in Examples 5 to 8, the total amount of NR and MOD-EPDM was 10 parts.
When the MOD-EPDM content is 25 parts by weight with respect to 0 parts by weight, the effect of suppressing the occurrence of cracks appears, and the occurrence of cracks can be completely suppressed. That is, MOD-EPD
Compared with ENB-EPDM, M has the effect of requiring less amount of it.

In Example 9, the ozone resistance was evaluated using liquid MOD-EPDM. MOD-EPDM
Even if it is a liquid, the liquid MOD-EPDM content is 2 with respect to 100 parts by weight of the total amount of NR and MOD-EPDM.
If it is 0 part by weight or more, it is possible to suppress the generation of cracks due to NR ozone.

Comparing Example 9 with Comparative Example 8, the polymer of Example 9 obtained using the Group IVB transition metal catalyst-based catalyst containing the zirconium catalyst component showed that the polymer of Example VB containing the vanadium catalyst component. Since the co-vulcanizability with the conjugated diene rubber is better than that of the polymer of Comparative Example 8 obtained by using the group-transition metal catalyst-based catalyst, the ozone resistance and the tensile strength (T _B ) are excellent. . The good co-vulcanizability of the polymer of Example 9 with the conjugated diene rubber is due to the use of a Group IVB transition metal catalyst-based catalyst containing a zirconium catalyst component, whereby Is supposed to be because there will be.

[Brief description of drawings]

FIG. 1 shows ethylene used in the present invention and α-
It is explanatory drawing which shows an example of the preparation process of the olefin polymerization catalyst used when manufacturing the random copolymer rubber which consists of olefin and 7-methyl-1,6-octadiene.

Claims (6)

[Claims] 1. A rubber composition comprising a random copolymer rubber (1) comprising ethylene, an α-olefin and 7-methyl-1,6-octadiene, and a conjugated diene rubber (2). (I) the molar ratio of ethylene and α-olefin (ethylene / α-olefin) in the random copolymer rubber (1) is in the range of 40/60 to 90/10, and (ii) the random copolymer The content of 7-methyl-1,6-octadiene in the polymer rubber (1) was in the range of 0.4 to 25 mol%, and (iii) the random copolymer rubber (1) was measured in decalin at 135 ° C. Intrinsic viscosity [η] is 0.1 dl / g <
[Η] <8 dl / g, and (iv) ¹³ C-NMR of the random copolymer rubber (1).
Intensity ratio D of Tαβ to Tαα in the spectrum
(= Tαβ / Tαα) is 0.5 or less, and (v) the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the B value calculated from the following formula are 1.
Ethylene-α-olefin-7-methyl, wherein the glass transition temperature Tg of the random copolymer rubber (1) determined by DSC is −53 ° C. or lower. -1,6-
Octadiene copolymer rubber composition; B = P _OE / (2P _E · P _O ), where P _E is 7-in the random copolymer rubber (1).
It is the content mole fraction of the ethylene component excluding the ethylene unit derived from the methyl-1,6-octadiene component, P _O
Is the mole fraction of the α-olefin component contained in the random copolymer rubber (1), and P _OE is the α-olefin ethylene based on the total number of dyad chains in the random copolymer rubber (1). It is the ratio of the number of chains]. 2. The content of the random copolymer rubber (1) is 5 to 95 parts by weight, and the conjugated diene rubber (2).
The ethylene / α-olefin. According to claim 1, characterized in that the content of 5 to 95 parts by weight [however, the total amount of (1) and (2) is 100 parts by weight].
7-Methyl-1,6-octadiene copolymer rubber composition. 3. A rubber composition comprising a random copolymer rubber (1) and a conjugated diene rubber (2), wherein the random copolymer rubber (1) has a cyclopentadienyl skeleton. IVB containing a ligand
Ethylene, α-olefin, and 7-methyl-in the presence of a Group IVB transition metal catalyst-based catalyst consisting of a group transition metal compound (a) and an organoaluminum oxy compound (b)
A copolymer of 1,6-octadiene, and (i) the random copolymer rubber (1) has a molar ratio of ethylene to α-olefin (ethylene / α-olefin) of 40/60 to 90. / 10, (ii) the content of 7-methyl-1,6-octadiene in the random copolymer rubber (1) is in the range of 0.4 to 25 mol%, and (iii) the random copolymerization weight. The intrinsic viscosity [η] of the integrated rubber (1) measured in decalin at 135 ° C. was 0.1 dl / g <
[Η] <8 dl / g, and (iv) ¹³ C-NMR of the random copolymer rubber (1).
Intensity ratio D of Tαβ to Tαα in the spectrum
(= Tαβ / Tαα) is 0.5 or less, and (v) the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the B value calculated from the following formula are 1.
Ethylene-α-olefin-7-methyl, wherein the glass transition temperature Tg determined by DSC of the random copolymer rubber (1) is −53 ° C. or lower. -1,6-
Octadiene copolymer rubber composition; B = P _OE / (2P _E · P _O ), where P _E is 7-in the random copolymer rubber (1).
It is the content mole fraction of the ethylene component excluding the ethylene unit derived from the methyl-1,6-octadiene component, P _O
Is the mole fraction of the α-olefin component contained in the random copolymer rubber (1), and P _OE is the α-olefin ethylene based on the total number of dyad chains in the random copolymer rubber (1). It is the ratio of the number of chains]. 4. The ethylene · α-olefin · according to claim 3, wherein the Group IVB transition metal compound (a) is a zirconium compound containing a ligand having a cyclopentadienyl skeleton. 7-Methyl-1,6-octadiene copolymer rubber composition. 5. The group IVB transition metal catalyst-based catalyst comprises a zirconium compound containing a ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound (b) and an organoaluminum compound (c). The ethylene / α-olefin / 7-methyl-1,6-octadiene copolymer rubber composition according to claim 3. 6. The content of the random copolymer rubber (1) is 5 to 95 parts by weight, and the conjugated diene rubber (2).
The content of ethylene is 5 to 95 parts by weight (however, the total amount of (1) and (2) is 100 parts by weight), and the ethylene / α-olefin. 7-Methyl-1,6-octadiene copolymer rubber composition.