JPH0733923A - Rubber composition of improved blooming resistance - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in blooming resistance, low- temperature flexibility, weather resistance, etc., by adding a specified amount of a (sulfur) compound and a specified amount of a vulcanization accelerator to a random copolymer rubber having a specified composition and specified properties. CONSTITUTION:The composition is prepared by adding 0.5-10 pts.wt. sulfur or sulfur compound and 1-20 pts.wt. vulcanization accelerator to an ethylene/ propylene/7-methyl-1,6-octadiene random copolymer rubber which has an ethylene/propylene molar ratio of 60/40 to 85/15, an iodine value of 7-32, an intrinsic viscosity of 1-4dl/g as measured in decalin at 135 deg.C, a Talphabeta/Talphaalpha intensity ratio in an NMR spectrum of: 0.5 or below, a B value of 1-1.5 wherein the B value is calculated from the NMR spectrum data according to the equation wherein PE is the molar fraction of the ethylene contained in the rubber; PO is the molar fraction of the propylene contained in the rubber; and POE is the rate of number of the propylene/ethylene chains to the total number of the diad chains and a glass transition temperature of -53 deg.C or below.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rubber composition having improved blooming, and more specifically, to a vulcanized rubber product in which the occurrence of blooming due to sulfur or a sulfur compound used as a vulcanizing agent and a vulcanization accelerator is prevented. In addition, it is possible to provide ethylene, which has a higher vulcanization rate, that is, vulcanization can be performed in a shorter time than a rubber composition containing a conventional ethylene / propylene / diene copolymer rubber as a main component. The present invention relates to a propylene / diene copolymer rubber composition.

[0002]

TECHNICAL BACKGROUND OF THE INVENTION Ethylene / propylene / diene copolymer rubber (hereinafter sometimes referred to as EPDM) is
Due to its excellent heat resistance, weather resistance, ozone resistance, etc., it is widely used for rubber parts for automobiles, rubber parts for electric / electronics, and rubber parts for civil engineering / construction.

However, EPDM has a slower vulcanization rate than other general-purpose rubbers. In particular, when vulcanizing EPDM using sulfur or a sulfur compound as a vulcanizing agent, these vulcanizing agents and vulcanization accelerators should be added in order to increase the vulcanization rate to the same level as other general-purpose rubbers. It is necessary to use a large amount. That is, in the conventional EPDM, 2 to 5 times the amount of the vulcanization accelerator is used as compared with general-purpose rubbers such as natural rubber (NR), styrene-butadiene rubber (SBR), and butadiene (BR).

Sulfur, a sulfur compound, and a thiuram compound, a dithioate compound, and a thiazole compound, which are used as a vulcanizing agent for EPDM and a vulcanization accelerator, originally have poor compatibility with EPDM, and therefore, they are not compatible with EPDM. When blended in a large amount, these vulcanizing agents and vulcanization accelerators contained in the obtained vulcanized rubber precipitate on the surface of the vulcanized rubber product and crystallize white, a so-called blooming phenomenon occurs. However, there is a problem of reducing the commercial value of vulcanized rubber products.

As a method for preventing the occurrence of such a blooming phenomenon, a method of combining a vulcanization accelerator for suppressing blooming, a small amount of a non-reactive phenol formaldehyde resin, a fatty acid ester or the like is added to suppress blooming. Various methods such as a method for preventing blooming by devising a method and a vulcanization method have been conventionally proposed.

However, in the above-mentioned method, there is a problem that the processability and various physical properties of the vulcanized rubber are impaired and the cost is increased, and an effective blooming preventing method has not yet been found. is there.

Further, depending on the application of EPDM, since it is used in cold regions or at low temperatures, it is required to have excellent low temperature flexibility. Therefore, sulfur used as a vulcanizing agent does not impair the excellent processability inherent in EPDM, physical properties of vulcanized rubber, heat resistance, weather resistance, ozone resistance, paintability, adhesiveness, and other properties. Alternatively, it is possible to provide a vulcanized rubber product which is excellent in blooming resistance and low-temperature flexibility, in which blooming caused by a sulfur compound and a vulcanization accelerator is prevented, and a conventional ethylene / propylene / diene copolymer rubber is provided. It is desired to develop a rubber composition having a higher vulcanization rate than that of the rubber composition containing the main component, that is, capable of performing sufficient vulcanization in a short time.

[0008]

SUMMARY OF THE INVENTION The present invention is intended to solve the problems associated with the prior art as described above, and has excellent processability inherent in EPDM, physical properties of vulcanized rubber, heat resistance and weather resistance. Without impairing various properties such as resistance and ozone resistance,
We can provide vulcanized rubber products with excellent blooming resistance and low-temperature flexibility, and
An object of the present invention is to provide a rubber composition having a faster vulcanization rate than a rubber composition containing a propylene / diene copolymer rubber as a main component.

[0009]

SUMMARY OF THE INVENTION A first blooming improved rubber composition according to the present invention comprises ethylene, propylene and 7-
100 parts by weight of random copolymer rubber (A) composed of methyl-1,6-octadiene, 0.5 to 10 parts by weight of sulfur or sulfur compound (B), and vulcanization accelerator (C) 1
To 20 parts by weight, the random copolymer (A) has (i) a molar ratio of ethylene and propylene (ethylene / propylene) in the range of 60/40 to 85/15, and (ii) ) The iodine value is in the range of 7 to 32, and (ii
i) The intrinsic viscosity [η] measured in decalin at 135 ° C is 1
dl / g <[η] <4 dl / g, and is (iv) T of Tαβ in ¹³ C-NMR spectrum.
The intensity ratio D to αα (= Tαβ / Tαα) is 0.5 or less, and the (B) ¹³ C-NMR spectrum and the B value calculated from the following formula are 1.00 to 1.50, (Vi) The glass transition temperature Tg determined by DSC is -53.
It is characterized by being below ℃.

B = P _OE / (2P _E · P _O ) In the above formula, P _E is 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 mole fraction of the propylene component contained in the random copolymer rubber, and P _OE is the propylene / total number of dyad chains in the random copolymer rubber.
It is the ratio of the number of ethylene chains.

A second blooming-improved rubber composition according to the present invention comprises ethylene, propylene and
100 parts by weight of random copolymer rubber (A) consisting of 7-methyl-1,6-octadiene, 0.5 to 10 parts by weight of sulfur or sulfur compound (B), and vulcanization accelerator (C) 1 to 20 The random copolymer rubber (A) contains 100 parts by weight, and the random copolymer rubber (A) 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 a Group IVB transition metal catalyst-based catalyst, ethylene, propylene and 7-methyl-1,6-octadiene are copolymerized, and (i) the molar ratio of ethylene and propylene (ethylene / Propylene) is in the range of 60/40 to 85/15, (ii) the iodine value is in the range of 7 to 32,
(Iii) Intrinsic viscosity [η] measured in decalin at 135 ° C
Is in the range represented by 1 dl / g <[η] <4 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 ℃.

The Group IVB transition metal compound (a) used in the production of the random copolymer (A) constituting the rubber composition is a zirconium compound containing a ligand having a cyclopentadienyl skeleton. Is 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
Propylene / 7-methyl-1,6-octadiene copolymer rubber is particularly preferred.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The rubber composition having improved blooming according to the present invention will be specifically described below.

The rubber composition with improved blooming according to the present invention contains a specific random copolymer rubber (A), sulfur or a sulfur compound (B) and a vulcanization accelerator (C) in a specific ratio. I will do it.

Random Copolymer Rubber (A) The random copolymer rubber (A) used in the present invention may be ethylene, propylene, and 7-methyl-1,6-octadiene (hereinafter sometimes referred to as MOD). ) And.

The random copolymer rubber (A) is obtained by copolymerizing ethylene, propylene and MOD in the presence of a specific Group IVB transition metal catalyst system catalyst, and has a specific composition and characteristics. Have. In particular, a random copolymer rubber (A) obtained by copolymerizing ethylene, propylene and MOD in the presence of a Group IVB transition metal catalyst-based catalyst containing a specific zirconium catalyst component 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 propylene (ethylene / propylene) of 60.
/ 40 to 85/15, preferably 63/37 to 82/1
It is in the range of 8. By using the random copolymer rubber (A) having a molar ratio of ethylene and propylene (ethylene / propylene) in the above range, a vulcanized rubber product having excellent mechanical strength and excellent blooming resistance can be obtained. A rubber composition that can be provided is obtained.

(Ii) This random copolymer rubber (A)
Has an iodine value in the range of 7 to 32. When the random copolymer rubber (A) having an iodine value in the above range is used, a vulcanized rubber product having excellent blooming resistance can be provided, and a rubber composition having a high vulcanization rate can be obtained. . In particular, when the random copolymer rubber (A) having an iodine value of 20 or more is used, a rubber composition having a high vulcanization rate can be 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%.

Also, a 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) This random copolymer rubber (A)
Has an intrinsic viscosity [η] of 1 measured in decalin at 135 ° C.
It is in the range represented by dl / g <[η] <4 dl / g. When the random copolymer rubber (A) having an intrinsic viscosity [η] in the above range is used, a rubber composition having excellent mechanical properties and the like originally possessed by EPDM and excellent processability can be obtained. .

(Iv) This random copolymer rubber (A)
Has an intensity ratio D (= Tαβ / Tαα) of Tαβ to Tαα in the ¹³ C-NMR spectrum of 0.5 or less, preferably 0.1 or less, more preferably 0.05 or less.

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.

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

Here, regarding the strength ratio D, ethylene
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 system catalyst containing a specific Group IVB transition metal catalyst component such as 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.

(V) This random copolymer rubber (A)
Has a B value calculated from the ¹³ C-NMR spectrum and the following formula of 1.00 to 1.50, preferably 1.0.
2 to 1.50, more preferably 1.02 to 1.45,
It is particularly preferably 1.02 to 1.40.

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 mole fraction of the propylene component contained in the random copolymer rubber, 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.

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-based 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) This random copolymer rubber (A)
Has a glass transition temperature Tg of −53 ° C. or lower determined by DSC (differential scanning calorimeter). Glass transition temperature Tg is -5
When the random copolymer rubber (A) having a temperature of 3 ° C. or lower is used, a rubber composition capable of providing a vulcanized rubber product 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, 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 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 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 ² , R ³
A zirconium compound in which one of R ⁴ 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. Also, R ³ and R ⁴
Is 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.

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

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

In the present invention, the above-mentioned 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 trimethyl aluminum, triethyl aluminum, tripropyl aluminum, triisopropyl aluminum, tri n-butyl aluminum, triisobutyl aluminum, and tri sec. -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,
Examples include a pentyl group, a hexyl group, an octyl group, a cyclopentyl group, a cyclohexyl group, a phenyl group and a tolyl group.

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, diisobutyl aluminum methoxide and the like.

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

[0069]

[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
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 a process for preparing a Group IVB transition metal catalyst-based catalyst containing a zirconium catalyst component used in the production of the random copolymer rubber (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 for mixing and contacting the Group IVB transition metal compound (a), the organoaluminum oxy compound (b) and the organoaluminum compound (c) is usually -100 to 200 ° C, preferably -70. ~ 100 ° C
It is desirable that the range is.

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

The molecular weight of the above random copolymer rubber 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. it can.

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

The polymer produced immediately after polymerization is recovered from the polymerization solution and dried by a conventionally known separation / recovery method to obtain a solid random copolymer rubber (A). Sulfur or sulfur compound (B) Sulfur or sulfur compound (B) used in the present invention
Is used as a vulcanizing agent.

Specific examples of sulfur include powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur, insoluble sulfur and the like. 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, powdered sulfur is preferably used. In the present invention, the sulfur or sulfur compound (B) is used in a proportion of 0.5 to 10 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the random copolymer rubber (A).

Since the above random copolymer rubber (A) used in the present invention has a high vulcanization rate, sulfur or a sulfur compound (depending on the kind, combination and addition amount of vulcanization accelerators described later can be selected. The addition amount of B) can be reduced.

Vulcanization accelerator (C) Specific examples of the vulcanization accelerator (C) used in the present invention include N-cyclohexyl-2-benzothiazolsulfenamide and N-oxydiethylene-2-benzothiazo. −
Rusulfenamide, N, N-diisopropyl-2-benzothiazol-sulfenamide, 2-mercaptobenzothiazole, 2- (2,4-dinitrophenyl) mercaptobenzothiazole, 2- (2,6 -Diethyl-4-morpholinothio) benzothiazole, dibenzothiazyl disulfide and other thiazole compounds; such as diphenylguanidine, triphenylguanidine, diorsonitrile guanidine, orthonitrile biguanide, diphenylguanidine phthalate Guanidine compounds; acetaldehyde-aniline reaction products, butyraldehyde-aniline condensates, hexamethylenetetramine, acetaldehyde ammonia and other aldehyde amines or aldehydes
-Ammonia-based compounds; 2-Imazozoline-based compounds such as mercaptoimidazoline; Thio-urea-based compounds such as thiocarbanilide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorsotolylthiourea; Tetramethylthiuram monosulfide, tetramethylthiuram disulfide , Tetraethylthiuram disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram tetrasulfide, and other thiuram-based compounds; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, butylphenyldithiocarbamate Zinc, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, dimethyldithio Dithio acid salt-based compounds such as Rubamin tellurium; Zante such dibutyl xanthate zinc - DOO compounds; may include compounds such as zinc white.

Further, as an example of a preferable combination of the vulcanization accelerator (C), dibenzothiadisulfide (MBT
S), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), tetramethylthiuram disulfide (TMTD) and dipentamethylenethiuram tetrasulfide (DPTT) in combination.

In the present invention, the vulcanization accelerator (C) is
1 to 100 parts by weight of the random copolymer rubber (A)
-20 parts by weight, preferably 2-10 parts by weight.

In the rubber composition according to the present invention, in addition to the above random copolymer rubber (A), sulfur or sulfur compound (B) as a vulcanizing agent and vulcanization accelerator (C),
Filler, softening agent, tackifier, vulcanization aid, anti-aging agent,
A foaming agent, a processing aid, a heat resistance stabilizer, a weather resistance stabilizer, an antistatic agent, a colorant, a lubricant, a flame retardant, an antiblooming agent and other compounding agents for rubber are compounded within a range not impairing the object of the present invention. be able to.

The above-mentioned fillers include fillers having a reinforcing property and fillers having no reinforcing property. Reinforcing filler is
It has the effect of enhancing the mechanical properties of vulcanized rubber, such as tensile strength, tear strength, and wear resistance. As such a filler, specifically, carbon black, silica, which may be surface-treated with a silane coupling agent or the like,
Examples include activated calcium carbonate and fine powder talc.
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.

The rubber composition according to the present invention can be prepared, for example, by the following method. That is, the rubber composition according to the present invention comprises a random copolymer rubber (A), a filler, a softening agent, and other necessary additives in a mixer such as a Banbury mixer at a temperature of 80 to 170 ° C. After kneading for about 3 to 10 minutes, roll like an open roll.
Sulfur or a sulfur compound (B) and a vulcanization accelerator (C) are additionally mixed using a roll, and the roll temperature is 40 to 80 ° C.
It can be prepared by kneading for 5 to 30 minutes and then dispensing. The rubber composition thus obtained is a ribbon-shaped or sheet-shaped rubber compound.

The rubber composition according to the present invention contains about 80% of the random copolymer rubber (A), sulfur or sulfur compound (B), vulcanization accelerator (C) and the above-mentioned additives.
It is also possible to feed directly into an extruder heated to -100 ° C, granulate it with a residence time of about 0.5 to 5 minutes, and prepare pellets.

The vulcanized rubber product is molded by molding the rubber composition according to the present invention obtained as described above into a desired shape using a molding machine such as an extrusion molding machine or a mold vulcanization molding machine. At the same time or by introducing the molded product into the vulcanization tank, it is usually 150
It can be obtained by vulcanizing at a temperature of ~ 250 ° C for 2 to 60 minutes. Vulcanization may be performed using a mold or may be performed without using a mold.

[0095]

The random copolymer rubber (A) composed of ethylene, propylene and 7-methyl-1,6-octadiene used in the present invention has a molar ratio of ethylene and propylene, an iodine value and an intrinsic viscosity [ [η], the strength ratio D and B value of Tαβ and Tαα in the ¹³ C-NMR spectrum, and the glass transition temperature Tg are in a specific range, so that a vulcanized rubber excellent in low-temperature flexibility can be provided, and The vulcanization rate is faster than that of conventional EPDM. Therefore, the amount of the vulcanization accelerator (C) used for vulcanizing the random copolymer rubber (A) can be considerably reduced as compared with the case of the conventional EPDM.

The random copolymer rubber (A)
Has excellent properties such as weather resistance, ozone resistance, and heat aging resistance. Since the rubber composition according to the present invention contains the random copolymer rubber (A), sulfur or a sulfur compound (B) as a vulcanizing agent, and a vulcanization accelerator (C), EPDM Has excellent processability, vulcanized rubber physical properties, heat resistance, weather resistance, ozone resistance, paintability, adhesiveness, and other properties, and has excellent blooming resistance and low-temperature flexibility. A vulcanized rubber product can be provided, and the vulcanization rate is faster than that of a conventional rubber composition containing an ethylene / propylene / diene copolymer rubber as a main component.

Therefore, the rubber composition according to the present invention having the above-mentioned effects can be used for various automobile parts such as window frames, glass run channels, door mirror boots, etc., which are required to have ozone resistance and adhesion, weather resistance and adhesion. It is suitable for applications such as waterproof sheets that require heat resistance, various civil engineering / building material parts, and various hoses that require heat resistance.

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 / propylene / 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, using a CLASTLASTMETER Model 3 manufactured by Japan Synthetic Rubber Co., Ltd. The torque change was measured at 170 ° C., and t ₉₀ [minutes] was obtained 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 in Tg measurement by DSC The sample is heated from room temperature (25 ° C) to 20 ° C / min at a rate of 18 ° C.
After raising the temperature to 0 ° C. and maintaining it at 180 ° C. for 2 minutes, this sample was cooled to −80 ° C. at a rate of −20 ° C./min, and 2
Hold the sample at −80 ° C. for a minute, and then repeat this sample at 20 ° C. /
The temperature was raised at a rate of min to obtain the Tg of the sample.

[3] Tensile test JIS K 6301 (198) was prepared by punching out a vulcanized rubber sheet.
No. 3 type dumbbell test piece described in 9 years) was prepared, and the test piece was used in accordance with the method defined in the same JIS K 6301 paragraph 3, measurement temperature 25 ° C., tensile speed 500
A tensile test was carried out under the condition of mm / min, and the tensile stress at break T _B and the elongation at break E _B were 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).
The compression set (CS) of the test piece heat-aged at 100 ° C. for 22 hours was determined.

[6] Blooming Test In the blooming test A method, after leaving the test piece for 1 month in a thermostatic chamber at 25 ° C., the state of blooming on the surface of the test piece was visually observed.

In the blooming test B method, the test piece was placed in an ozone test tank having an ozone concentration of 50 pphm and 40 ° C., and after 48 hours, the occurrence of blooming on the surface of the test piece was visually observed.

The blooming resistance was evaluated as follows. (3 step evaluation) ◎: Blooming is not observed. ○: Blooming is slightly generated. ×: Blooming is severely generated.

[0108]

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 70/30 and an iodine value of 20 and the intrinsic viscosity [η] measured in decalin at 135 ° C. was 2.4 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.
2 and the glass transition temperature was -61 ° C.

[0112]

[Reference Examples 2 to 5] The same operation as in Reference Example 1 was carried out, and ethylene / propylene / 7-methyl-1,6- shown in Table 1 was used.
Octadiene copolymer rubber [hereinafter referred to as MOD-EPDM
Sometimes referred to as (2), (3), (4), (5)]
Got

[0113]

Example 1 MOD-EPDM obtained in Reference Example 1
(1) 100 parts by weight, zinc white 5 parts by weight, stearic acid 1 part by weight, FEF carbon black 80 parts by weight,
55 parts by weight of heavy calcium carbonate, 65 parts by weight of paraffinic process oil, and 1 part by weight of polyethylene glycol were kneaded for 5 minutes with a Banbury mixer having a capacity of 1.7 liters (manufactured by Kobe Steel, Ltd.).

1.5 parts by weight of sulfur (vulcanizing agent), 1.0 part by weight of dibenzothiazyl disulfide (MBTS), N-cyclohexyl-2-benzothiazolyl sulfene was added to the kneaded product thus obtained. Amide (CBS) 1.5 parts by weight, tetramethylthiuram disulfide (TMTD)
0.8 parts by weight and 0.8 parts by weight of dipentamethylene thiuram tetrasulfide (DPTT) were added, and the mixture was kneaded for 10 minutes with an 8-inch open roll having a width of 20 inches (the temperature of the front roll and the rear roll was 40 ° C.), and rubber compounding The thing was prepared.

170% of the above rubber compound was hot-pressed.
℃, 10 minutes (15 minutes for compression set measurement), 150kg
Vulcanization and molding were performed under f · cm ² to prepare a test piece, and the above test was performed.

The results are shown in Table 1.

[0117]

Second Embodiment In the first embodiment, the MOD-EPDM is used.
MOD-EPDM obtained in Reference Example 2 instead of (1)
(2) is used, and 1.0 part by weight of sulfur is used, and N-cyclohexyl-2-benzothiazolylsulfenamide (CB
S) 0.5 parts by weight, tetramethylthiuram disulfide (TMTD) 0.5 parts by weight, dipentamethylene thiuram tetrasulfide (DPTT) 0.5 parts by weight except that the compounding amount was changed to the same as Example 1. I did. The blending amount of dibenzothiazyl disulfide (MBTS) is
It is 1.0 part by weight as in Example 1.

The results are shown in Table 1.

[0119]

Comparative Example 1 In Example 1, the MOD-EPDM
ENB-EPDM shown in Table 1 instead of (1)
Example 1 was repeated except that (1) was used.

The results are shown in Table 1.

[0121]

Third Embodiment In the first embodiment, the MOD-EPDM is used.
MOD-EPDM obtained in Reference Example 3 instead of (1)
The same procedure as in Example 1 was performed except that (3) was used.

The results are shown in Table 1.

[0123]

Comparative Example 2 In Example 1, the MOD-EPDM
MOD-EPDM obtained in Reference Example 4 instead of (1)
Example 1 was repeated except that (4) was used.

The results are shown in Table 1.

[0125]

[Table 1]

From Table 1, the following can be understood. Comparative Example 1
Caused a lot of blooming and the vulcanization rate was slower than in Examples 1 and 2.

In Comparative Example 2, the molar ratio of ethylene / propylene of MOD-EPDM is out of the range of the present invention 88/1.
Since it is as large as 2, blooming has occurred.

[0128]

COMPARATIVE EXAMPLE 3 In Comparative Example 1, ENB-EPDM (1) was mixed with ENB-EPDM (1) at the time of kneading with a Banbury mixer, in addition to the above-mentioned additives, an alkylphenol resin [Hitaanol 150 manufactured by Hitachi Chemical Co., Ltd.]
1] The procedure of Comparative Example 1 was repeated except that 5 parts by weight was added.

The results are shown in Table 2.

[0130]

[Comparative Example 4] In Comparative Example 1, except that 2 parts by weight of distearyl dimethyl ammonium chloride as an anti-blooming agent was added to ENB-EPDM (1) in addition to the above-mentioned additives during kneading with an open roll. ,
The same procedure as in Comparative Example 1 was performed.

The results are shown in Table 2.

[0132]

[Comparative Example 5] The MOD with an iodine value of 20 in Example 1
Example 1 was repeated except that MOD-EPDM (5) with an iodine value of 4 obtained in Reference Example 5 was used instead of -EPDM (1).

The results are shown in Table 2.

[0134]

[Table 2]

From Table 2, the following can be understood. Comparative Example 3
In comparison with Comparative Example 1, the blooming preventing effect of the alkylphenol resin is recognized, but the compression set after heat aging is large.

In Comparative Example 4, the blooming preventing effect of distearyldimethylammonium chloride is considerably recognized as compared with Comparative Example 1, but the vulcanization rate is slow.

In Comparative Example 5, the iodine value of MOD-EPDM was out of the range of the present invention and was as small as 4, so that the vulcanization rate was slower than in Example 1, and blooming occurred.

[Brief description of drawings]

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

Claims (4)

[Claims] 1. Ethylene, propylene and 7-methyl-
100 parts by weight of a random copolymer rubber (A) composed of 1,6-octadiene, 0.5 to 10 parts by weight of sulfur or a sulfur compound (B),
And a vulcanization accelerator (C) in an amount of 1 to 20 parts by weight, and the random copolymer (A) has (i) a molar ratio of ethylene and propylene (ethylene / propylene) of 60/40 to 85. / 15, (ii) iodine value is in the range of 7 to 32, (iii) intrinsic viscosity [η] measured in 135 ° C decalin.
Is in the range represented by 1 dl / g <[η] <4 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 by the following formula are 1.00 to 1.50, and vi) A rubber composition with improved blooming characterized by 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 propylene component in the random copolymer rubber, and P _OE is All dyads (d in random copolymer rubber
yad) The ratio of the number of propylene / ethylene chains to the number of chains]. 2. Ethylene, propylene and 7-methyl-
100 parts by weight of a random copolymer rubber (A) composed of 1,6-octadiene, 0.5 to 10 parts by weight of sulfur or a sulfur compound (B),
And a vulcanization accelerator (C) in an amount of 1 to 20 parts by weight, wherein the random copolymer rubber (A) contains a ligand having a cyclopentadienyl skeleton.
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)
Copolymerized with 6-octadiene, and (i) the molar ratio of ethylene and propylene (ethylene / propylene) is in the range of 60/40 to 85/15, and (ii) the iodine value is 7 to 32. (Iii) Intrinsic viscosity [η] measured in decalin at 135 ° C
Is in the range represented by 1 dl / g <[η] <4 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 by the following formula are 1.00 to 1.50, and vi) A rubber composition with improved blooming characterized by 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 propylene component in the random copolymer rubber, and P _OE is All dyads (d in random copolymer rubber
yad) The ratio of the number of propylene / ethylene chains to the number of chains]. 3. The rubber composition according to claim 2, wherein the Group IVB transition metal compound (a) is a zirconium compound containing a ligand having a cyclopentadienyl skeleton. 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 according to claim 2.