JP3370142B2 - Rubber composition for wire coating rubber - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rubber composition for an electric wire coating rubber , and more specifically, it can provide an electric wire coating rubber excellent in external damage resistance, crush resistance and low temperature flexibility.
About the wire coating rubber for the rubber composition capable of high-speed molding.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Ethylene / propylene / non-conjugated diene copolymer rubber (hereinafter sometimes referred to as EPDM) has excellent weather resistance, low temperature flexibility, heat aging resistance,
It is used for electrical insulation parts such as rubber for electric wire coating by taking advantage of its electrical insulation properties. In a commonly used electric wire, an insulating layer is provided around the conducting wire, and a sheath is provided on the outer circumference of the insulating layer. Such an electric wire is usually formed by continuously vulcanizing rubber forming an insulating layer and rubber forming a sheath. In such a molding method, it is desirable to vulcanize the rubber forming the insulating layer and immediately continuously vulcanize the rubber forming the sheath to efficiently produce an electric wire in a short time. Has a problem that the wire coating rubber cannot be molded at a high speed because the vulcanization speed is slow. Further, in the case of an electric wire which is not covered with a sheath and whose insulating layer is exposed, the external damage resistance and the crush resistance of the insulating layer are particularly problematic.

Therefore, it is conceivable to increase the vulcanization density of EPDM so that EPDM has a high modulus and use this EPDM as a wire coating rubber. EPDM like this
If used, the wire coating rubber can be molded at high speed, and the wire coating rubber can be protected against external damage without lowering the productivity of the wire.
The crush resistance can be improved.

However, in order to increase the vulcanization density and increase the modulus of the conventional EPDM, only the method of increasing the non-conjugated diene content of EPDM can be considered. EP
When the content of non-conjugated diene in DM increases, EPDM deteriorates in flexibility at low temperatures, and in low temperature atmospheres such as winter and cold regions, rubber elasticity, which is indispensable for electric wires, becomes poor, resulting in damage resistance. However, there is a problem that it becomes very difficult to improve the crush resistance.

[0005]

[0006]

[0007]

Accordingly, external damage resistance,耐潰are property, the appearance of the wire coating rubber for the rubber composition for wire coating rubber having excellent low-temperature flexibility, etc. can speed molding is desired conventionally.

[0009]

It is an object of the present invention to solve the above-mentioned problems associated with the prior art, and to form a wire-covered rubber excellent in external damage resistance, crush resistance and low temperature flexibility at high speed. It is an object of the present invention to provide a rubber composition for electric wire coating rubber that can be used.

[0010]

[0011]

SUMMARY OF THE INVENTION The first rubber composition for electric wire coating rubber according to the present invention comprises ethylene, α-olefin and 7-methyl.
A rubber composition containing a random copolymer rubber (A) containing -1,6-octadiene, a vulcanizing agent (B), and a filler (C), wherein the random copolymer (A )
Is (i) the molar ratio of ethylene to α-olefin (ethylene / α-olefin) is in the range of 60/40 to 80/20, (ii) iodine value is in the range of 5 to 30,
(Iii) Intrinsic viscosity [η] measured in decalin at 135 ° C
Is in the range represented by 1 dl / g <[η] <5 dl / g, and (iv) the intensity ratio D (= Tαβ / Tαα) of Tαβ to Tαα in the ¹³ C-NMR spectrum is 0.5.
And (b) the B value calculated from the ¹³ C-NMR spectrum and the following formula is 1.00 to 1.50, and (vi) the glass transition temperature Tg calculated by DSC is -53.
It is characterized by being below ℃.

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

The second rubber composition for electric wire coating rubber according to the present invention is a random copolymer rubber (A) comprising ethylene, α-olefin and 7-methyl-1,6-octadiene, A rubber composition comprising a vulcanizing agent (B) and a filler (C), wherein the random copolymer rubber (A) contains a ligand having a cyclopentadienyl skeleton. Ethylene, an α-olefin, and 7 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)
-Copolymerized with methyl-1,6-octadiene,
And (i) the molar ratio of ethylene to α-olefin (ethylene / α-olefin) is in the range of 60/40 to 80/20, (ii) the iodine value is in the range of 5 to 30,
(Iii) Intrinsic viscosity [η] measured in decalin at 135 ° C
Is in the range represented by 1 dl / g <[η] <5 dl / g, and (iv) the intensity ratio D (= Tαβ / Tαα) of Tαβ to Tαα in the ¹³ C-NMR spectrum is 0.5.
And (b) the B value calculated from the ¹³ C-NMR spectrum and the above formula is 1.00 to 1.50, and (vi) the glass transition temperature Tg determined by DSC is -53.
It is characterized by being below ℃.

[0014]

[0015]

[0016] Examples of the Group IVB transition metal compound used in the production of the random copolymer constituting the aforementioned wire coating rubber for the rubber composition (A) (a), the ligand having a cyclopentadienyl skeleton Zirconium compounds containing are preferred.

The random copolymer rubber (A) comprises 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.

[0018]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a specific description will be given about the wire coating rubber for the rubber composition of the present invention.

The wire coating rubber for the rubber composition according to the present invention
Is a specific random copolymer rubber (A) and a vulcanizing agent (B)
And a filler (C).

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

Α constituting the random copolymer rubber (A)
-Olefin is an α-olefin having 3 to 20 carbon atoms, and 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-pentene, 4-ethyl- 1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-
Dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene and the like can be mentioned. These α-
The olefins may be used alone or in combination.

In the present invention, α-olefin having 3 to 6 carbon atoms is preferably used, and particularly α-olefin having 3 carbon atoms is used.
-Olefin, ie propylene is preferably used. The above random copolymer rubber (A) has a specific IVB
It is a copolymer of ethylene, α-olefin, and MOD in the presence of a group-transition metal catalyst-based catalyst, and has a specific composition and characteristics. In particular, in the presence of a Group IVB transition metal catalyst system catalyst containing a specific zirconium catalyst component,
A random copolymer rubber (A) obtained by copolymerizing ethylene, α-olefin and MOD is preferable. Details of the method for producing the random copolymer rubber (A) will be described later.

The random copolymer rubber (A) used in the present invention has the following composition and properties. (I) The random copolymer rubber (A) has a molar ratio of ethylene and α-olefin (ethylene / α-olefin) of 60/40 to 80/20, preferably 65/35.
The range is from ~ 78/22. When a random copolymer rubber (A) having a molar ratio of ethylene and α-olefin (ethylene / α-olefin) in the above range is used,
Excellent in mechanical strength, rubber composition capable of providing a wire coating rubber having excellent rubber elasticity at low temperatures is obtained.

(Ii) The random copolymer rubber (A) has an iodine value of 5 to 30, preferably 10 to 25.
Is in the range. When iodine value using random copolymer rubber (A) in the range described above, excellent in external damage resistance, provides a wire coating rubber that holds the excellent heat aging resistance of EPDM is inherent A rubber composition that can be obtained is obtained.

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) with the same iodine value, the vulcanization rate of MOD-EPDM is 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 PDM has a high diene content, if the diene content exceeds 4 mol%, the effect of improving the vulcanization rate is lost.
On the other hand, MOD-EPD produced using a Group IVB transition metal catalyst-based catalyst containing a specific zirconium catalyst component
M 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
When the iodine value of PDM is increased in order to accelerate the vulcanization rate, the low temperature flexibility is proportionally deteriorated. 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 iodine value.

(Iii) Furthermore, the random copolymer rubber (A) has an intrinsic viscosity [η] measured in decalin at 135 ° C. in a range represented by 1 dl / g <[η] <5 dl / g. As a rubber composition for electric wire coating rubber, 1d
l / g <[η] <arbitrary random copolymer rubber (A) is preferred in the range represented by 3 dl / g. Intrinsic viscosity [η]
Random copolymer rubber (A) in which is within the above range
With, it is possible to provide a wire coating rubber having excellent external damage resistance, a rubber composition excellent in extrusion processability can be obtained.

(Iv) Further, this random copolymer rubber (A) 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 (A).

The strength ratio D of the random copolymer rubber (A) 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
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 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.

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.

The same applies to α-olefins other than propylene. (V) Further, the random copolymer rubber (A) has a B value calculated from the ¹³ C-NMR spectrum and the following formula of 1.00 to 1.5.
0, preferably 1.02 to 1.50, more preferably 1.02 to 1.45, particularly preferably 1.02 to 1.4
It is 0.

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

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 above B value, the shorter the blocky chain of ethylene or α-olefin, the more uniform the distribution of ethylene and α-olefin, 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.

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 system 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 (A) has a glass transition temperature Tg determined by DSC (differential scanning calorimeter) of −53 ° C. or lower. Random copolymer rubber (A) having a glass transition temperature Tg of −53 ° C. or lower
With a rubber composition capable of providing a wire coating rubber having excellent low-temperature flexibility can be obtained.

Random copolymer rubber (A) 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.

The Group IVB transition metal compound (a) containing a ligand having a cyclopentadienyl skeleton used in the present invention is a Group IV compound represented by the following general formula [I].
Examples thereof include Group B transition metal compounds.

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, 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 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 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 (A) 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 can be adjusted by changing the polymerization conditions such as the polymerization temperature, and can also be adjusted by controlling the amount of hydrogen (molecular weight modifier) used. it can.

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 (A). Vulcanizing agent (B) Examples of the vulcanizing agent (B) used in the present invention include sulfur, sulfur compounds and organic peroxides.

Specific examples of sulfur include powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur and insoluble sulfur. As a sulfur compound,
Specific examples thereof include sulfur chloride, sulfur dichloride, and polymer polysulfide. Further, a sulfur compound which releases active sulfur at the vulcanization temperature and vulcanizes, such as morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, dipentamethylenethiuram tetrasulfide, etc. can also be used.

In the present invention, the sulfur or sulfur compound is used in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the random copolymer rubber (A). To be

When sulfur or a sulfur compound is used as the vulcanizing agent (B), it is preferable to use a vulcanization accelerator together. As the vulcanization accelerator, specifically, N-
Cyclohexyl-2-benzothiazol-sulfenamide, N-oxydiethylene-2-benzothiazol-sulfenamide, N, N-diisopropyl-2-benzothiazol-sulfenamide, 2-mercaptobenzothiazo-
2- (2,4-dinitrophenyl) mercaptobenzothiazole, 2- (2,6-diethyl-4-morpholinothio) benzothiazole, dibenzothiazyl disulfide and other thiazole compounds; diphenyl Guanidine, triphenylguanidine, diorsonitrile guanidine,
Guanidine compounds such as orthonitrile biguanide and diphenylguanidine phthalate; acetaldehyde
-Aniline reaction products, butyraldehyde-aniline condensates, aldehyde amines such as hexamethylenetetramine, acetaldehyde ammonia, or aldehyde-ammonia compounds; 2-imidazoline compounds such as 2-mercaptoimidazolines; thiocarbanilide, diethylthiourea, dibutylthiourea, tri Methylthiourea,
Thiourea-based compounds such as diorthotolylthiourea;
Thiuram-based compounds such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide;
Zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc di-n-butyldithiocarbamate,
Dithioate compounds such as zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, tellurium dimethyldithiocarbamate; zanthate compounds such as zinc dibutylxanthate; zinc oxide etc. A compound can be mentioned.

In the present invention, the vulcanization accelerator is 0.1 to 100 parts by weight of the random copolymer rubber (A).
It is used in a proportion of 20 parts by weight, preferably 0.2 to 10 parts by weight.

The organic peroxide may be any compound generally used for peroxide vulcanization of rubber. For example, dicumyl peroxide, di-t-butyl peroxide,
Di-t-butylperoxy-3,3,5-trimethylcyclohexane, t-butylhydroperoxide, t-butylcumyl peroxide, benzoyl peroxide, 2,5-dimethyl-2,5-di (t-butyl) Peroxine) hexyne-3,2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-dimethyl-
2,5-mono (t-butylperoxy) -hexane,
Examples include α, α′-bis (t-butylperoxy-m-isopropyl) benzene. Among them, dicumyl peroxide, di-t-butylperoxide and di-t-butylperoxy-3,3,5-trimethylcyclohexane are preferably used. These organic peroxides are 1
They may be used alone or in combination of two or more.

In the present invention, the organic peroxide is 3 × 10 ^{−4 with} respect to 100 g of the random copolymer rubber (A).
It is used in a proportion of up to 5 × 10 ^-2 mol, but it is desirable to appropriately determine the optimum amount according to the required physical property values.

When an organic peroxide is used as the vulcanizing agent (B), it is preferable to use a vulcanization auxiliary together. Specific examples of the vulcanization aid include sulfur; quinone dioxime compounds such as p-quinone dioxime; methacrylate compounds such as polyethylene glycol dimethacrylate; diallyl phthalate and triallyl cyanurate. Examples thereof include allyl compounds such as G. and the like; other maleimide compounds; divinylbenzene and the like.

In the rubber composition for electric wire coating rubber, it is preferable to use an organic peroxide as the vulcanizing agent (B).

Filler (C) The filler (C) used in the present invention includes a filler having a reinforcing property and a filler having no reinforcing property.

The reinforcing filler has an effect of enhancing mechanical properties such as tensile strength, tear strength and abrasion resistance of the vulcanized rubber. As such a filler, specifically,
Examples thereof include carbon black, which may be surface-treated with a silane coupling agent, silica, activated calcium carbonate, and fine talc powder. In the present invention, any carbon black that is usually used for rubber can be used regardless of its type.

Further, the filler having no reinforcing property increases the hardness of the rubber product without affecting the physical properties so much,
Used to reduce costs. As such a filler, specifically, talc, clay,
Examples include calcium carbonate.

In the present invention, the filler (C) is 20 to 20 parts by weight with respect to 100 parts by weight of the random copolymer rubber (A).
It is used in an amount of 200 parts by weight, preferably 50 to 150 parts by weight.

[0101] The wire coating rubber for rubber compositions according to the present invention, the above random copolymer rubber (A), vulcanizing agent (B)
In addition to the filler and the filler (C), a vulcanization accelerator and a vulcanization aid can be blended as described above. In addition, a softening agent, a processing aid, a foaming agent and other compounding agents for rubber can be added. , Can be added within a range that does not impair the object of the present invention.

Examples of the softening agent include softening agents usually used for rubber, that is, various mineral oils, synthetic oils, ester plasticizers and the like. Specifically, various mineral oils usually used as rubber process oils, for example, paraffinic, naphthene-based, and aromatic mineral oils, butene oligomers, synthetic hydrocarbon oils such as ethylene / α-olefin cooligomers, and polyglycol oils. , Polyphenyl ether oil, ester oil, phosphate ester oil, polychlorotrifluoroethylene oil, fluoroester oil, chlorinated biphenyl oil, silicone oil and the like.

The softening agent is a random copolymer rubber (A) 1
It is used in a proportion of 10 to 120 parts by weight, preferably 30 to 80 parts by weight, relative to 00 parts by weight. As the processing aid, a processing aid usually used for rubber is used in an amount of 10 parts by weight or less based on 100 parts by weight of the random copolymer rubber (A).
Preferably, it may be used in a proportion of 1 to 5 parts by weight.

[0103] wire coating rubber for the rubber composition according to the present invention
It can be prepared, for example, by the following method.
That is, wire coating rubber for the rubber composition according to the present invention,
Using a mixer such as a Banbury mixer, the random copolymer rubber (A), the filler (C), and necessary additives such as a softening agent are added at a temperature of 80 to 170 ° C. for about 3 to 10 ° C.
After kneading for a minute, a roll such as an open roll is used to additionally mix the vulcanizing agent (B) and, if necessary, a vulcanization accelerator or a vulcanization aid, and the roll temperature is 40 to 80 ° C. ~
It can be prepared by kneading for 30 minutes and then dispensing. The rubber composition thus obtained is a ribbon-shaped or sheet-shaped rubber compound.

The rubber composition for electric wire coating rubber according to the present invention comprises a random copolymer rubber (A), a vulcanizing agent (B),
The filler (C) and the above additives are directly fed to the extruder heated to about 80 to 100 ° C., and the residence time is about 0.5 to
It is also possible to granulate for 5 minutes to prepare a pellet form.

[0105]

The random copolymer rubber (A) 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, an iodine value of , Intrinsic viscosity [η], ¹³ C-NM
Intensity ratio D, B between Tαβ and Tαα in the R spectrum
Since the value and the glass transition temperature Tg are in a specific range,
It is possible to provide a vulcanized rubber excellent in external damage resistance, crush resistance, and low-temperature flexibility, and further, the vulcanization speed is high.

Further, this random copolymer rubber (A)
Has excellent properties such as weather resistance, ozone resistance, and heat aging resistance. The rubber composition for electric wire coating rubber according to the present invention,
The random copolymer rubber (A), a vulcanizing agent (B),
Since it contains the filler (C), it is possible to mold at high speed an electric wire coating rubber excellent in external damage resistance, crush resistance and low temperature flexibility.

[0107]

The present invention will be described below with reference to examples.
The present invention is not limited to these examples. The evaluation test methods for the ethylene / α-olefin / diene copolymer rubber and the vulcanized rubber in Examples and Comparative Examples are as follows.

[1] Physical Property Test of Unvulcanized Rubber The physical property test of unvulcanized rubber was carried out in accordance with JIS K 6300. Mooney viscosity [ML _{1 + 4} (130 ° C.)], Mooney scorch time (t ₅ [min]) and tΔ ₃₀ [min] were determined. tΔ ₃₀ is said to represent the degree of vulcanization rate. Regarding unvulcanized rubber, Nippon Synthetic Rubber Co., Ltd.
The change in torque was measured at 160 ° C. using a CURLAST METER Model 3 manufactured by CURELAST METER, and t ₉₀ [min] was determined and used as the vulcanization rate. The shorter t ₉₀ is, the faster the vulcanization rate is.

[2] Tg Tg of ethylene / α-olefin / diene copolymer rubber
Was measured with a differential scanning calorimeter (DSC). This glass transition temperature is an index of the low temperature flexibility of the ethylene / α-olefin / diene copolymer rubber.

・ 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.

[3] 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 ), 300% modulus (M ₃₀₀ ), Tension
Stress at break T_B And tensile elongation at break E_B Was measured.

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

[5] Compression set test The compression set test was conducted according to JIS K 6301 (1989).
And the compression set (CS) was determined.

[6] Heat Deformation Test The heat deformation test is performed according to JIS C 3005.
The reduction rate [%] of the thickness after heat deformation was determined. This reduction rate is an index of the crush resistance of the vulcanized rubber.

(Test conditions) Heating temperature: 90 ° C., 120 ° C., 150 ° C. Load: 10.5 kg [7] Dyeing wear test The dyeing wear test was conducted in accordance with JIS L-0823, and the weight change rate before and after the test. [%] Was calculated. This rate of change in weight serves as an index of the scratch resistance of the vulcanized rubber.

(Test conditions) Test load: 200 g Friction surface: 20 × 20 mm Size of test piece: 25 × 210 mm Friction piece: Cloth of size 20 × 20 mm (Kanakin No. 3) Friction frequency: 500 times [8] Low temperature torsion test (German torsion test) The low temperature torsion test was performed according to JIS K 6301, and T ₂ [° C], T ₅ [° C], T ₁₀ [° C], and freezing temperature [° C] were obtained. These temperatures are indicators of the low temperature flexibility of the vulcanized rubber.

(Test conditions) Torsion constant of twisted wire: 0.5 gf · cm / degree Immersion time: 10 minutes Torsion time: 5 seconds

[0119]

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. The obtained copolymer [hereinafter, sometimes referred to as MOD-EPDM (1)] is a rubber having a molar ratio of ethylene and propylene (ethylene / propylene) of 67/33 and an iodine value of 22 and the intrinsic viscosity [η] measured in 135 ° C. decalin was 1.92 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 1.1.
4, and the glass transition temperature was -61 ° C.

[0123]

[0124]

[Table 1]

The ethylene / propylene-5-ethylidene-2-norbornene copolymer rubber [E
The quality of NB-EPDM (1), (2)] is shown in Table 2.

[0126]

[Table 2]

[Examples and Comparative Examples of Rubber Compositions for Rubber Coated with Electric Wire]

[0128]

Comparative Example 1 ENB-EPDM (1) 1 shown in Table 2
00 parts by weight, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, 100 parts by weight of mistron vapor talc [filler], and 20 parts by weight of paraffinic oil were added to a Banbury mixer having a capacity of 4.3 liters [( Made by Kobe Steel Co., Ltd.].

To the kneaded product thus obtained, 6.8 parts by weight of dicumyl peroxide and 3.5 parts by weight of p- (p-dibenzoylquinone) dioxime [vulcanization aid] were added to obtain a mixture of 8 inches. Roll (Temperature of front roll and rear roll 50
After kneading at 160 ℃, dispense into sheets and
0 minutes, 20 minutes press vulcanization, thickness 2 with different vulcanization time
mm vulcanized sheets were prepared.

The vulcanized sheet thus obtained was subjected to the above-mentioned physical property tests and the like according to the above-mentioned methods. Further, for the unvulcanized rubber composition before performing the vulcanization, according to the above method,
The Mooney viscosity [ML _{1 + 4} (130 ° C.)], Mooney scorch time (t ₅ ), tΔ ₃₀ and t ₉₀ were determined.

The results are shown in Table 3.

[0132]

Comparative Example 2 In Comparative Example 1, ENB-EPDM
ENB-EPDM shown in Table 2 instead of (1)
The same procedure as in Comparative Example 1 was carried out except that (2) was used.

The results are shown in Table 3.

[0134]

Example 1 In Comparative Example 1, ENB-EPDM
MOD-EPDM obtained in Reference Example 1 instead of (1)
The procedure of Comparative Example 1 was repeated except that (1) was used.

The results are shown in Table 3.

[0136]

[Table 3]

From Table 3, the following was found. Comparative Example 1 using ENB-EPDM (1) having a low iodine value and Comparative Example 2 using ENB-EPDM (2) having a high iodine value
In comparison, in order to improve the crush resistance and the scratch resistance, the iodine value of ENB-EPDM should be increased, that is, the ENB content should be increased, but the low temperature flexibility is impaired.

On the other hand, comparing Example 1 with Comparative Example 2, the MOD-EPDM (1) used in Example 1 has the same iodine value as the iodine value of ENB-EPDM (2) used in Comparative Example 2. Despite having a value, Example 1 exhibits better low temperature flexibility than Comparative Example 2 and is also very excellent in trauma resistance.

In addition, although Example 1 and Comparative Example 2 use EPDM having the same iodine value, Example 1 has a much higher vulcanization rate than Comparative Example 2.

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[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 (A) which consists of an olefin and 7-methyl-1,6-octadiene.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01B 3/16-3/56

Claims (4)

(57) [Claims] 1. A random copolymer rubber (A) comprising ethylene, an α-olefin, and 7-methyl-1,6-octadiene, a vulcanizing agent (B), and a filler (C). The random copolymer rubber (A) has the molar ratio (i) of ethylene and α-olefin (ethylene / α-olefin) in the range of 60/40 to 80/20. Yes, (ii) iodine value is in the range of 5-30, (iii) intrinsic viscosity [η] measured in 135 ° C decalin
Is in the range represented by 1 dl / g <[η] <5 dl / g, and (iv) Tαβ of Tαβ in the ¹³ C-NMR spectrum.
The intensity ratio D (= Tαβ / Tαα) is 0.5 or less, (v) the ¹³ C-NMR spectrum and the B value calculated from the following formula are 1.00 to 1.50, vi) A rubber composition for an electric wire coating rubber, which has a glass transition temperature Tg determined by DSC of −53 ° C. or lower; B = P _OE / (2P _E · P _O ), where P _E is 7-methyl in random copolymer rubber
Is the content mole fraction of the ethylene component excluding the ethylene unit derived from the -1,6-octadiene component, P _O is the content mole fraction of the α-olefin component in the random copolymer rubber, P _OE Is the total dyad (d
yad) The ratio of the number of α-olefin / ethylene chains to the number of chains]. 2. A random copolymer rubber (A) comprising ethylene, an α-olefin and 7-methyl-1,6-octadiene, a vulcanizing agent (B) and a filler (C). IVB, wherein the random copolymer rubber (A) contains a ligand having a cyclopentadienyl skeleton.
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), ethylene, α-olefin, and 7-methyl-
Copolymerized with 1,6-octadiene, and (i) the molar ratio of ethylene and α-olefin (ethylene / α-olefin) is in the range of 60/40 to 80/20, (ii) The iodine value is in the range of 5 to 30, and (iii) the intrinsic viscosity [η] measured in decalin at 135 ° C.
Is in the range represented by 1 dl / g <[η] <5 dl / g, and (iv) Tαβ of Tαβ in the ¹³ C-NMR spectrum.
The intensity ratio D (= Tαβ / Tαα) is 0.5 or less, (v) the ¹³ C-NMR spectrum and the B value calculated from the following formula are 1.00 to 1.50, vi) A rubber composition for an electric wire coating rubber, which has a glass transition temperature Tg determined by DSC of −53 ° C. or lower; B = P _OE / (2P _E · P _O ), where P _E is 7-methyl in random copolymer rubber
Is the content mole fraction of the ethylene component excluding the ethylene unit derived from the -1,6-octadiene component, P _O is the content mole fraction of the α-olefin component in the random copolymer rubber, P _OE Is the total dyad (d
yad) The ratio of the number of α-olefin / ethylene chains to the number of chains]. 3. The rubber composition for electric wire coating rubber according to claim 2, wherein the Group IVB transition metal compound (a) is a zirconium compound containing a ligand having a cyclopentadienyl skeleton. object. 4. 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 rubber composition for an electric wire coating rubber according to claim 2.