JP3445320B2 - Ethylene propylene 7-methyl-1,6-octadiene copolymer rubber composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION The present invention relates to ethylene / propylene /
More specifically, the present invention relates to a 7-methyl-1,6-octadiene terpolymer rubber composition, which has excellent co-vulcanization properties with nitrile rubber (NBR), weatherability without impairing the excellent oil resistance of nitrile rubber. , An ethylene / propylene / 7-methyl-1,6-octadiene terpolymer rubber composition capable of providing a vulcanized rubber excellent in ozone resistance, heat aging resistance and low temperature flexibility.

[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. , Taking advantage of its characteristics, weather stripping, door glass run channel, radiator hose,
It is often used for automobile parts such as brake parts.

On the other hand, nitrile rubber (NBR) has excellent oil resistance and is therefore widely used for hoses and packings around engines. By the way, EPDM and NBR
There are many parts that require physical properties that combine the excellent properties of both polymers. Therefore, various attempts have been made to improve the oil resistance of EPDM or the heat resistance and low temperature flexibility of NBR.

For example, L. Spenadel and RL Sutphin
Rubber Age, 102, (12), 55 (1970), EPD
The possibility of blending M and NBR has been queried. During the blending of EPDM and NBR, carbon black, a vulcanization accelerator, etc. are added. However, the non-polar polymer EPDM and the polar polymer NB
Since the compatibility with R is not good, a uniform compound cannot be obtained by simply adding carbon black, a vulcanization accelerator, etc. at the time of blending EPDM and NBR.

In order to blend EPDM, NBR, carbon black, a vulcanization accelerator and the like to obtain a uniform compound, first of all, it is necessary to take measures against the difference in polarities of both EPDM and NBR polymers. .

As a countermeasure, a kneading method has been studied, and JMMitchl; RubberChem. Technol., 50, 43
0 (1977) refers to an attempt to prepare a carbon masterbatch (CMB) by blending carbon black with EPDM and NBR, and to use the carbon masterbatch to homogenize the dispersibility of the compound. .

In addition, an attempt to make the dispersibility of the vulcanization accelerator uniform by using lead trioxide (Pb ₃ O ₄ ) is WHWh.
Referred to in the literature by ttington; Rubber Ind., 9, 151 (1975).

Secondly, in order to obtain good covulcanizability with NBR, which is a diene polymer, the vulcanization rate is significantly slower.
In some cases, an attempt was made to solve the problem by increasing the vulcanization rate of PDM. For example, it is a method of increasing the vulcanization rate of EPDM by preliminarily reacting EPDM and sulfur, and this method is well known as a pendant sulfur method.

At present, blend compounds containing EPDM and NBR are commercially available using some or all of these techniques. However, although the problem regarding the polarity of the polymer can be solved to some extent by the above method, the EPDM after blending has a poor co-vulcanizability with NBR because the vulcanization rates of EPDM and NBR are significantly different. There is. Thus, the co-vulcanizability with NBR has become a fundamental problem with conventional EPDM.

[0010]

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-propylene-7 having a low temperature flexibility and a vulcanization rate almost equal to those of NBR. -By providing a methyl-1,6-octadiene copolymer rubber, without impairing the inherent excellent mechanical properties and oil resistance of NBR,
An object of the present invention is to provide a rubber composition capable of imparting a vulcanized rubber excellent in low temperature flexibility, weather resistance, ozone resistance and heat resistance.

[0011]

SUMMARY OF THE INVENTION A first ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber composition according to the present invention comprises ethylene, propylene and 7-methyl-1,6-
Random copolymer rubber consisting of octadiene (1)
If, now from a nitrile rubber (2), the random copolymerization
The content of the integrated rubber (1) is 20 to 80 parts by weight, and
The content of the nitrile rubber (2) is 20 to 80 parts by weight.
However, the total amount of (1) and (2) is 100 parts by weight.
And (i) the molar ratio of ethylene and propylene (ethylene / propylene) in the random copolymer rubber (1) is 5
5/45 to 80/20, (ii) the random copolymer rubber (1) has an iodine value of 13 to 40, and (iii) 135 of the random copolymer rubber (1). The intrinsic viscosity [η] measured in decalin at 0.2 ° C is 0.2 dl / g <
[Η] <6.0 dl / g, and (iv) intensity ratio D (= Tαβ to Tαα in the ¹³ C-NMR spectrum of the random copolymer rubber (1).
Tαβ / Tαα) is 0.5 or less, and (v) the B value obtained by calculating from the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the following formula is 1.
The glass transition temperature Tg determined by DSC of the random copolymer rubber (1) is −53 ° C. or less.

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, P _O is the content mole fraction of the propylene component in the random copolymer rubber (1), and P _OE is the total content in the random copolymer rubber (1). It is the ratio of the number of propylene / ethylene chains to the number of dyad chains.

The second ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber composition according to the present invention comprises a random copolymer rubber (1) and a nitrile rubber (2). And the random copolymer rubber (1)
Content of 20-80 parts by weight, the nitrile rubber
The content of (2) is 20 to 80 parts by weight [however, (1)
And the total amount of (2) is 100 parts by weight],
The random copolymer rubber (1) comprises a Group IVB transition metal compound (a) containing a ligand having a cyclopentadienyl skeleton and an organoaluminum oxy compound (b). In the presence of ethylene, propylene and 7-methyl-1,6-octadiene, and (i) the molar ratio of ethylene and propylene in the random copolymer rubber (1). (Ethylene / Propylene) is 5
5/45 to 80/20, (ii) the random copolymer rubber (1) has an iodine value of 13 to 40, and (iii) 135 of the random copolymer rubber (1). The intrinsic viscosity [η] measured in decalin at 0.2 ° C is 0.2 dl / g <
[Η] <6.0 dl / g, and (iv) intensity ratio D (= Tαβ to Tαα in the ¹³ C-NMR spectrum of the random copolymer rubber (1).
Tαβ / Tαα) is 0.5 or less, and (v) the B value obtained by calculating from the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the following formula is 1.
The glass transition temperature Tg determined by DSC of the random copolymer rubber (1) is −53 ° C. or less.

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
Propylene / 7-methyl-1,6-octadiene copolymer rubber is particularly preferred.

[0015]

[0016]

DETAILED DESCRIPTION OF THE INVENTION The ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber composition according to the present invention will be specifically described below.

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

Random Copolymer Rubber (1) The random copolymer rubber (1) used in the present invention includes ethylene, propylene, and 7-methyl-1,6-octadiene (hereinafter sometimes abbreviated as MOD). ) And consists of.

The present inventors have found that vulcanization which is excellent in low temperature flexibility, weather resistance, ozone resistance and heat resistance without deteriorating the excellent mechanical properties and oil resistance originally possessed by nitrile rubber (NBR). By intensively researching to obtain a rubber composition capable of providing a rubber, copolymerizing 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, It has been found that an EPDM can be obtained which exhibits a vulcanization rate equivalent to that of NBR and can provide a rubber composition capable of imparting a vulcanized rubber excellent in the above properties.

In the present invention, ethylene, propylene and MOD are added in the presence of a specific Group IVB transition metal catalyst system catalyst.
A specific random copolymer rubber (1) obtained by copolymerizing and 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, propylene and MOD is preferably used. Details of the method for producing the random copolymer rubber (1) will be described later.

Even if an attempt is made to copolymerize ethylene, propylene and MOD in the presence of a vanadium catalyst or a titanium catalyst which has been conventionally used in the production of EPDM, the activity of these components is extremely lowered, and therefore these components are added. It could not be industrially copolymerized. Therefore,
The present inventors diligently studied 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 exhibit good polymerization activity. In the present invention, it was decided to copolymerize ethylene, propylene, and MOD using a specific Group IVB transition metal catalyst-based catalyst.

Further, the present inventors have investigated a co-catalyst and copolymerized ethylene, propylene and MOD with a catalyst system in which an organoaluminum oxy compound is combined with a zirconium catalyst as a co-catalyst. We found that it is possible to control the structure of a polymer with excellent co-vulcanization properties, and came to find 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 propylene (ethylene / propylene) of 55.
/ 45 to 80/20, preferably 60/40 to 75/2
5, more preferably 65/35 to 70/30. When a random copolymer rubber (1) having a molar ratio of ethylene and propylene (ethylene / propylene) in the above range is blended with NBR, a vulcanized rubber excellent in mechanical strength and low-temperature flexibility is obtained. It is possible to obtain a rubber composition capable of imparting.

(Ii) The random copolymer rubber (1) has an iodine value of 13-40, preferably 13-2.
It is in the range of 5. When an ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber having an iodine value in the above range is used, it has excellent co-vulcanizability with NBR,
It is possible to obtain a rubber composition that retains the excellent heat aging resistance inherent in EPDM.

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%.

Further, 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) Further, the random copolymer rubber (1) has an intrinsic viscosity [η] measured in decalin at 135 ° C. of 0.2 dl / g <[η] <6.0 dl / g, preferably 0.5 dl / g <[η] <4.0 dl / g, more preferably 0.5 dl / g <[η] <3.0 dl /
It is in the range represented by g. When the random copolymer rubber (1) having an intrinsic viscosity [η] in the above range is used, the blendability with NBR is good, the excellent mechanical strength characteristics of NBR are retained, and the heat resistance and It is possible to obtain a rubber composition capable of providing a vulcanized rubber having excellent weather resistance.

(Iv) Further, this random copolymer rubber (1) has a T of Tαβ in the ¹³ C-NMR spectrum.
The intensity ratio D (= Tαβ / Tαα) to αα is 0.5 or less, preferably 0.1 or less, more preferably 0.05.
It is the following.

The 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.

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

Here, regarding the strength ratio D, ethylene
The propylene / 7-methyl-1,6-octadiene copolymer rubber will be described. In this case, the peak appearing at 45 to 46 ppm in the ¹³ C-NMR spectrum is Tα.
The peak appearing at α and at 32 to 33 ppm is Tα.
Belonging to β respectively, the integrated value of each peak portion is obtained, and the intensity ratio D is calculated.

The strength 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.

Copolymerizing ethylene, propylene and 7-methyl-1,6-octadiene in the presence of a Group IVB transition metal catalyst based catalyst containing a Group IVB transition metal catalyst component such as certain zirconium. Therefore, the above-mentioned strength ratio D is 0.5 or less, ethylene-propylene-7-methyl-
A 1,6-octadiene copolymer rubber can be obtained.

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.

(V) Further, this random copolymer rubber (1) has a B value calculated from the ¹³ C-NMR spectrum and the following formula of 1.00 to 1.50, preferably 1.02. ˜1.50, more preferably 1.02-1.
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 molar fraction of the ethylene component excluding the ethylene unit derived from the 7-methyl-1,6-octadiene component, and P _O is the molar fraction of the propylene component in the random copolymer rubber (1). And P _OE is the ratio of the number of propylene / 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, and J.C.Randall (Mac
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.

The larger the B value, the shorter the blocky chain of ethylene or propylene, the more uniform the distribution of ethylene and propylene, and the narrower the compositional 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.

By copolymerizing ethylene, propylene 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. , The above B value is 1.00 to 1.
50-ethylene-propylene-7-methyl-1,6-
An octadiene copolymer rubber can be obtained.

However, even if ethylene, propylene and 7-methyl-1,6-octadiene are copolymerized in the presence of a Group IVB transition metal catalyst system catalyst containing a titanium catalyst component, the B value within the above range It is not possible to obtain an ethylene / propylene / 7-methyl-1,6-octadiene copolymer rubber having 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. Random copolymer rubber (1) having a glass transition temperature Tg of −53 ° C. or lower
When 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, propylene, 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.

The group IVB transition metal compound (a) containing a ligand having a cyclopentadienyl skeleton used in the present invention is, for example, a group IVB transition metal compound 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 cyclopentadienyl group; methylcyclopentadienyl group, dimethylcyclopentadienyl group, 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 above 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 above-mentioned 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.

Specific examples of the zirconium compound represented by the above general formula [II] are shown 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, aliphatic hydrocarbons such as octadecane, 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. Trimethyl aluminum, triethyl aluminum, triisopropyl aluminum, triisobutyl aluminum,
Trialkylaluminums such as trioctylaluminum and tri2-ethylhexylaluminum; Alkenylaluminums such as isoprenylaluminum; Dialkylaluminum halides such as dimethylaluminium chloride, diethylaluminum chloride, diisopropylaluminum chloride, diisobutylaluminum chloride, dimethylaluminum bromide; Aluminum sesquichloride, ethyl aluminum sesquichloride,
Alkyl aluminum sesquihalides such as isopropyl aluminum sesquichloride, butyl aluminum sesquichloride, ethyl aluminum sesquibromide; alkyl aluminum dihalides such as methyl aluminum dichloride, ethyl aluminum dichloride, isopropyl aluminum dichloride, ethyl aluminum dibromide; diethyl aluminum hydride, diisobutyl aluminum Alkyl aluminum hydride such as hydride.

As the organoaluminum compound (c), a compound represented by the following formula [V] can 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 and diisobutyl aluminum methoxide.

(Ii) A compound represented by R ⁵ _n Al (OSiR ⁷ ₃ ) _3-n , for example, (C ₂ H ₅ ) ₂ Al (OSi (C
_{H 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.

[0074]

[Chemical 1]

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 to about 0.
00005-0.1 mmol, preferably about 0.000
Used in an amount of 1-0.05 mmol.

In the organoaluminum oxy compound (b), the aluminum atom in the organoaluminum oxy compound (b) is 1 mol based on 1 mol of the zirconium atom.
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, ethylene, propylene,
When copolymerizing with 7-methyl-1,6-octadiene, the above group IVB transition metal catalyst-based catalyst constituting the above catalyst
Group IVB transition metal compound (a), organoaluminum oxy compound (b), and further organoaluminum compound (c)
May be separately fed to the polymerization reactor, or before the copolymerization reaction, a Group IVB transition metal catalyst-based catalyst containing the Group IVB transition metal catalyst component is prepared in advance. Good.

FIG. 1 shows the steps 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 are:
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 at which the Group IVB transition metal compound (a), the organoaluminum oxy compound (b) and the organoaluminum compound (c) are mixed and contacted 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 also 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 the 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 20 to 80 parts by weight, preferably 3 to 100 parts by weight of the total amount of the random copolymer rubber (1) and the nitrile rubber (2).
It is used in a proportion of 0 to 70 parts by weight.

Nitrile Rubber (2) The nitrile rubber (2) used in the present invention has a bound acrylonitrile amount of usually 15 to 50% by weight, preferably 25.
Is in the range of 50% by weight. By using a nitrile rubber having a bound acrylonitrile amount in the above range, it is possible to obtain a rubber composition capable of imparting a vulcanized rubber having excellent oil resistance.

In the present invention, the nitrile rubber (2)
Is used in an amount of 20 to 80 parts by weight, preferably 30 to 70 parts by weight, based on 100 parts by weight of the total amount of the random copolymer rubber (1) and the nitrile rubber (2).

Rubber composition and vulcanized product thereof Ethylene propylene 7-methyl-1, according to the present invention
As described above, the 6-octadiene copolymer rubber composition is a random copolymer rubber (1), that is, ethylene.
It is composed of propylene / 7-methyl-1,6-octadiene copolymer rubber and nitrile 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 nitrile 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 the function of improving properties such as weather resistance and ozone resistance of the vulcanized rubber, and the nitrile rubber (2). Since the vulcanized rubber has a function of improving properties such as strength, a vulcanized rubber excellent in strength, weather resistance, ozone resistance and dynamic fatigue resistance can be obtained from the rubber composition according to the present invention. it can.

When 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-mentioned 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 usually used for rubber is used. Specifically, petroleum-based softening agents such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, and petrolatum; 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. Among them, 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, calender roll, or 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.

[0101]

The random copolymer rubber composed of ethylene, propylene and 7-methyl-1,6-octadiene used in the present invention has a molar ratio of ethylene and propylene,
Since the iodine value, the intrinsic viscosity [η], the intensity ratio D of Tαβ and Tαα in the ¹³ C-NMR spectrum, the B value, and the glass transition temperature Tg are in specific ranges, high stereoregularity, narrow composition distribution, and excellent It has low-temperature flexibility, and exhibits extremely good co-vulcanizability with NBR.

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, has a covulcanizability with a nitrile rubber. Is extremely excellent in

Ethylene / Propylene / 7- According to the Present Invention
Since the methyl-1,6-octadiene copolymer rubber composition is composed of such a random copolymer rubber and a nitrile rubber, it retains the excellent mechanical properties and oil resistance originally possessed by the nitrile rubber. At the same time, 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 applications such as automobile parts such as wiper blades, rubber hoses, rubber packing, and seal parts. Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

The EPDs in Examples and Comparative Examples
The evaluation test methods for M and the vulcanized sheet are as follows. [1] Physical Property Test of Unvulcanized Rubber The physical property test of unvulcanized rubber is carried out in accordance with JIS K 6300. For unvulcanized rubber, Curastometer Model 3 manufactured by Japan Synthetic Rubber Co., Ltd. is used. The change in torque was measured at 160 ° C., and t ₉₀ [min] was determined and used as the vulcanization rate. The shorter t ₉₀ is, the faster the vulcanization rate is.

[2] Tensile test A vulcanized rubber sheet is punched out and JIS K 6301 (198
3rd type dumbbell test piece described in 9 years)
Then, the test piece was used to comply with JIS K 6301 Clause 3
According to the specified method, the measurement temperature is 25 ° C., the pulling speed is 500.
Tensile test was performed under the condition of mm / min and 100% module
Russ (M₁₀₀ ), 200% modulus (M ₂₀₀ ), 30
0% modulus (M₃₀₀ ), Tensile stress at break T_B and
Tensile elongation at break E_B Was 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] Compression set test The compression set test was conducted according to JIS K 6301 (1989).
And the compression set (CS) was determined.

Heat treatment temperature in compression test 100 ° C., 120 ° C., 150 ° C. Heat treatment time in compression test 22 hours [5] Oil resistance test The oil resistance test is carried out in accordance with the dipping test specified in JIS K 6301. Volume change rate of test piece (ΔV
Seeking [%]), also the tensile rate of change of intensity (T _B) in accordance with _{JIS K 6301 [S C (T} B)], the rate of change of elongation _{(E B) [S C (} E B)] and JIS A hardness It was determined the difference between the (H _S).

JIS No. 3 oil was used as the test oil. The test conditions are 100 ° C. and 72 hours. [6] Ozone resistance test (1) Static ozone test The static ozone test is based on JIS K 6301, ozone concentration 80pphm, measurement temperature 40 ° C, elongation rate (static extension).
40% condition, 24 hours, 48 hours, 72 hours, 96 hours, 120 hours, 144 hours, 1 from the start of the test
The state of generation of cracks was observed and evaluated after the elapse of each 68 hours. (2) Dynamic ozone test The dynamic ozone test is based on JIS K 6301, ozone concentration 80pphm, measurement temperature 40 ° C, elongation rate (dynamic elongation).
0 → 30%, 5 cycles / second, 24 hours, 48 hours, 72 hours, 96 hours, 120 hours from the start of the test
Evaluation was performed by observing the state of crack generation after the lapse of each of the hours, 144 hours, and 168 hours.

[7] Low Temperature Flexibility Low temperature flexibility is evaluated by the glass transition temperature (Tg) of EPDM alone before blending with nitrile rubber (NBR), and the glass transition temperature is measured by a differential scanning calorimeter (DS
It was measured in C). The glass transition temperature of the nitrile rubber itself was also measured.

・ Temperature cycle of Tg measurement by DSC: 18 ° C. from room temperature (25 ° C.) to 20 ° C./min
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.

[0113]

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, dehydration-purified hexane, a hexane solution of bis (1,3-dimethylcyclopentadienyl) zirconium dichloride (concentration 0.05 mmol / liter), and triisobutylaluminum were introduced into the polymerization vessel from the upper portion of the polymerization vessel. Hexane solution (concentration 17 mmol / l), hexane slurry solution of methylalumoxane (3 mg atom / aluminum atom /
Liter) and a hexane solution of 7-methyl-1,6-octadiene (concentration: 0.25 liter / liter) were continuously supplied.

Further, ethylene and propylene were continuously fed into the polymerization vessel from the upper portion of the polymerization vessel. This copolymerization reaction was performed at 50 ° C. Then, a small amount of methanol was added to the polymerization solution extracted from the lower part of the polymerization reactor to stop the polymerization reaction, and the copolymer was separated from the solvent by steam stripping treatment.
Hg), and dried for 24 hours.

With the above operation, ethylene / propylene / 7
A methyl-1,6-octadiene copolymer was obtained. Obtained copolymer (hereinafter referred to as MOD-EPDM)
Is a rubber, the molar ratio of ethylene and propylene (ethylene / propylene) is 67.2 / 32.8, the iodine value is 23.7, and the intrinsic viscosity [135] measured in a decalin solvent. η] is 2.2 dl / g,
The Mooney viscosity [ML _{1 + 4} (100 ° C.)] was 69. In addition, T of Tαβ in the ¹³ C-NMR spectrum is
The strength ratio D to αα was less than 0.01, the B value was 1.30, and the glass transition temperature was −62 ° C.

[0117]

Comparative Example 1 75 parts by weight of nitrile rubber [NBR 1042, manufactured by Nippon Zeon Co., Ltd.] having a Mooney viscosity [ML _{1 + 4} (100 ° C.)] of 80 and an acrylonitrile content of 30%, and a mole of ethylene and propylene. Ethylene / propylene / 5-ethylidene-2-norbornene copolymer rubber having a ratio (ethylene / propylene) of 68/32, an iodine value of 22, and a Mooney viscosity [ML _{1 + 4} (100 ° C.)] of 70 (hereinafter, ENB -EPDM] 25 parts by weight, zinc white 5 parts by weight, stearic acid 1 part by weight, HAF carbon black [Asahi Carbon Co., Ltd. # 80] 50 parts by weight, dioctyl phthalate (DOP: plasticizer) ) 15 parts by weight and oil [Sansen 4 manufactured by Japan Sun Oil Co., Ltd.]
240] 10 parts by weight and the anti-aging agent [2,2'-methylenebis (4-methyl-6-t-butylphenol, Ouchi Shinko Chemical Industry Co., Ltd., Nocrac NS-6] 1 part by weight with a capacity of 1 The mixture was kneaded with a 7-liter Banbury mixer [manufactured by Kobe Steel, Ltd.].

To the kneaded product thus obtained, 1.5 parts by weight of sulfur and 1.2 parts by weight of a vulcanization accelerator [NOXCELLER CZ, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.] were added to give 8 parts.
Inch roll (Temperature of front roll and rear roll: 65
After kneading at 0 ° C.), the mixture was dispensed into a sheet, and t was determined by using a curlastometer type 3 manufactured by Japan Synthetic Rubber Co., Ltd.
_A vulcanized sheet with a thickness of 2 mm is prepared by pressing under the conditions of 160 ° C x t ₉₀ (min) [160 ° C x t ₉₀ +2 (min) for compression set test] based on ₉₀ (min) (160 ° C). did.

The vulcanized sheet thus obtained was subjected to the above-mentioned physical property tests and the like according to the above-mentioned methods. The results are shown in Table 1.

[0120]

Comparative Example 2 In Comparative Example 1, nitrile rubber and E
The procedure of Comparative Example 1 was repeated, except that the amount of NB-EPDM was changed to 50 parts by weight.

The results are shown in Table 1.

[0122]

Comparative Example 3 In Comparative Example 1, nitrile rubber and E
The procedure of Comparative Example 1 was repeated, except that the amounts of NB-EPDM compounded were changed to 25 parts by weight and 75 parts by weight, respectively.

The results are shown in Table 1.

[0124]

Example 1 Except that MOD-EPDM of Reference Example 1 was used instead of ENB-EPDM in Comparative Example 1.
The same procedure as in Comparative Example 1 was performed.

The results are shown in Table 2.

[0126]

Example 2 In Example 1, nitrile rubber and M
Example 1 was repeated except that the amount of OD-EPDM was changed to 50 parts by weight.

The results are shown in Table 2.

[0128]

Example 3 In Example 1, nitrile rubber and M
Example 1 was repeated except that the amounts of OD-EPDM compounded were changed to 25 parts by weight and 75 parts by weight, respectively.

The results are shown in Table 2.

[0130]

[Table 1]

[0131]

[Table 2]

[Brief description of drawings]

FIG. 1 is a process for preparing a catalyst for olefin polymerization used in producing a random copolymer rubber composed of ethylene, propylene and 7-methyl-1,6-octadiene used in the present invention. It is explanatory drawing which shows an example.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Patent 3182858 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 1/00-101/16

Claims (4)

(57) [Claims] 1. Ethylene, propylene and 7-methyl-
A rubber composition comprising a random copolymer rubber (1) comprising 1,6-octadiene and a nitrile rubber (2), wherein the content of the random copolymer rubber (1) is 20 to 80.
The content of the nitrile rubber (2) is 20 parts by weight.
To 80 parts by weight [however, the total amount of (1) and (2) is 100 parts by weight], and (i) the molar ratio of ethylene and propylene in the random copolymer rubber (1) (ethylene / Propylene) is 5
5/45 to 80/20, (ii) the random copolymer rubber (1) has an iodine value of 13 to 40, and (iii) 135 of the random copolymer rubber (1). The intrinsic viscosity [η] measured in decalin at 0.2 ° C is 0.2 dl / g <
[Η] <6.0 dl / g, and (iv) intensity ratio D (= Tαβ to Tαα in the ¹³ C-NMR spectrum of the random copolymer rubber (1).
Tαβ / Tαα) is 0.5 or less, and (v) the B value obtained by calculating from the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the following formula is 1.
Ethylene-propylene-7-methyl-1 having a glass transition temperature Tg of −53 ° C. or lower as determined by DSC of the random copolymer rubber (1). , 6-octadiene copolymer rubber composition; B = P _OE / (2P _E · P _O ), where P _E is 7-in the random copolymer rubber (1).
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 content mole fraction of the propylene component in the random copolymer rubber (1), P _OE is the ratio of the number of propylene / ethylene chains to the total number of dyad chains in the random copolymer rubber (1)]. 2. A rubber composition comprising a random copolymer rubber (1) and a nitrile rubber (2), wherein the content of the random copolymer rubber (1) is 20 to 80.
The content of the nitrile rubber (2) is 20 parts by weight.
To 80 parts by weight [however, the total amount of (1) and (2) is 100 parts by weight], wherein the random copolymer rubber (1) contains a ligand having a cyclopentadienyl skeleton. Including IVB
Ethylene, propylene, and 7-methyl-1, in the presence of a Group IVB transition metal catalyst-based catalyst comprising a group transition metal compound (a) and an organoaluminum oxy compound (b)
Is copolymerized with 6-octadiene, and (i) the random copolymer rubber (1) has a molar ratio of ethylene and propylene (ethylene / propylene) of 5
5/45 to 80/20, (ii) the random copolymer rubber (1) has an iodine value of 13 to 40, and (iii) 135 of the random copolymer rubber (1). The intrinsic viscosity [η] measured in decalin at 0.2 ° C is 0.2 dl / g <
[Η] <6.0 dl / g, and (iv) intensity ratio D (= Tαβ to Tαα in the ¹³ C-NMR spectrum of the random copolymer rubber (1).
Tαβ / Tαα) is 0.5 or less, and (v) the B value obtained by calculating from the ¹³ C-NMR spectrum of the random copolymer rubber (1) and the following formula is 1.
Ethylene-propylene-7-methyl-1 having a glass transition temperature Tg of −53 ° C. or lower as determined by DSC of the random copolymer rubber (1). , 6-octadiene copolymer rubber composition; B = P _OE / (2P _E · P _O ), where P _E is 7-in the random copolymer rubber (1).
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 content mole fraction of the propylene component in the random copolymer rubber (1), P _OE is the ratio of the number of propylene / ethylene chains to the total number of dyad chains in the random copolymer rubber (1)]. 3. The ethylene-propylene-7- according to claim 2, wherein the Group IVB transition metal compound (a) is a zirconium compound containing a ligand having a cyclopentadienyl skeleton. A methyl-1,6-octadiene copolymer rubber composition. Wherein said Group IVB transition metal catalyst based catalyst, characterized by comprising a zirconium compound containing a ligand having a cyclopentadienyl skeleton, an organoaluminum oxy-compound (b) and the organoaluminum compound (c) Ethylene propylene 7 according to claim 2 or 3
-Methyl-1,6-octadiene copolymer rubber composition.