JP2000072934A - Rubber composition for anti-vibration rubber - Google Patents

Abstract

(57) [Problem] To provide a rubber composition capable of providing a vibration-proof rubber excellent in vibration-proof properties, mechanical properties, and compression set. SOLUTION: (A) an ethylene unit, a 1-butene unit,
And a specific ethylene-based copolymer rubber having a non-conjugated polyene unit, and a rubber composition for a vibration-proof rubber containing (B) a vulcanizing agent and / or a crosslinking agent as a main component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition for vibration damping rubber, and more particularly, to a rubber composition containing a specific ethylene copolymer rubber and a vulcanizing agent and / or a cross-linking agent. The present invention relates to a rubber composition from which a vibration-proof rubber excellent in compression set and mechanical properties can be obtained.

[0002]

2. Description of the Related Art Personal computers, game machines,
Anti-vibration rubbers are frequently used in CD-ROMs, DVD-ROMs, and in-vehicle CDs used as storage devices such as DVDs. Conventionally, butyl rubber and halogenated butyl rubber have been used as these anti-vibration rubbers. I have. However, butyl rubber has a drawback that it is inferior in mechanical properties and compression set, and vibration-proof rubber excellent in compression set is desired.

On the other hand, vulcanizates of ethylene / propylene / non-conjugated diene copolymer (EPDM) rubber are excellent in mechanical properties, compression set, heat resistance, weather resistance and the like. Widely used for industrial parts. However, conventional vulcanizates of EPDM are inferior in anti-vibration properties and are not low in hardness, and are not used for anti-vibration applications.

[0004]

On the other hand, the present inventors have found that a vulcanizate of EPDM produced by a metallocene catalyst system is:
Although it has low hardness and excellent vibration isolation performance, it was found that the mechanical properties were insufficient. An object of the present invention is to provide a rubber composition capable of providing a vibration-proof rubber having low hardness and excellent vibration-proof properties, mechanical properties, and compression set.

[0005]

According to the present invention, the following rubber composition for an anti-vibration rubber is provided to achieve the above object of the present invention. (1) (A) an ethylene copolymer rubber having a unit derived from ethylene, a unit derived from 1-butene, and a unit derived from a non-conjugated polyene and satisfying the following requirements, and (B) vulcanization A rubber composition for an anti-vibration rubber comprising an agent and / or a crosslinking agent as a main component. Requirements The molar ratio (ethylene / 1-butene) of the unit derived from ethylene to the unit derived from 1-butene is 20/80.
８５85/15 Iodine value 0.5 ニ ー 50 Mooney viscosity (ML1 + 4, 100 ° C.) 20２０350
The glass transition temperature (Tg) determined by a differential scanning calorimeter (DSC) is −50 ° C. to −80 ° C. (2) The non-conjugated polyene in the ethylene copolymer rubber (A) is represented by the following formula: The rubber composition for an anti-vibration rubber according to the above (1), which is a non-conjugated polyene represented by (I). Formula (I) CH ₂ ＣＨCH—X—CR ¹ ＣＲCR ² —R ³ (wherein, X represents a saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, and R ¹ and R ² are the same or different. Differently, it represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R ³ represents an alkyl group having 1 to 8 carbon atoms, except that both R ¹ and R ² are hydrogen atoms. (A) The rubber composition for an anti-vibration rubber as described in (2) above, wherein the (A) ethylene copolymer rubber further contains a unit derived from α, ω-diene represented by the following formula (II). object. Formula _{(II) CH 2 = CH- (} CH 2) m-CH = CH 2 ( wherein, m is an integer of from 1 to 10.)

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The (A) ethylene copolymer rubber used in the rubber composition of the present invention comprises units derived from ethylene, 1-butene and a non-conjugated polyene (hereinafter referred to as “ethylene units”, “ethylene units”, respectively). 1-butene units "and" non-conjugated polyene units "). (A) Ethylene unit and 1 in ethylene copolymer rubber
-Molar ratio to butene units (ethylene / 1-butene) is
20 / 80-85 / 15, preferably 30 / 70-82
/ 12, more preferably 50/50 to 80/20 (the above requirement). When the molar ratio is within the above range,
The mechanical strength, rubber elasticity and low-temperature characteristics are preferably maintained in a well-balanced manner.

[0007] Non-conjugated polyenes include, for example, 5
-Ethylidene-2-norbornene, dicyclopentadiene, 5-propylidene-2-norbornene, 5-vinyl-2-norbornene, 2,5-norbornadiene, 1,
Cyclic polyenes such as 4-cyclohexadiene, 1,4-cyclooctadiene, and 1,5-cyclooctadiene;
1,4-hexadiene, 1,5-heptadiene, 1,6-
Examples include chain dienes such as octadiene, 1,7-nonadiene, and 1,8-decadiene.

Further, as the non-conjugated polyene, a chain non-conjugated polyene represented by the following formula (I) can be preferably mentioned. Specifically, 4-methyl-1,4-hexadiene, 5-methyl- 1,4-hexadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 6-methyl-1,6-octadiene, 7-methyl-1,6-octadiene, 3,7- Dimethyl-1,6-
Octadiene, 5,7-dimethyl-1,6-octadiene, 7-methyl-1,7-nonadiene, 8-methyl-1,
7-nonadiene, 8-methyl-1,8-decadiene, 9
-Methyl-1,8-decadiene, 9-methyl-1,9-undecadiene, 10-methyl-1,9-undecadiene, 10-methyl-1,10-dodecadiene, 11-methyl-1,10-dodecadiene, 12 -Methyl-1,11
-Tridecadienes, 13-methyl-1,11-tridecadienes, 12-methyl-1,12-tetradecadienes,
13-methyl-1,12-tetradecadiene, 13-methyl-1,13-bentadecadiene, 14-methyl-1,
13-pentadecadiene, 4-ethylidene-6-methyl-1,6-octadiene, 4-ethylidene-7-methyl-1,6-octadiene, 4-ethylidene-3,7-dimethyl-1,6-octadiene, 4-ethylidene-5,7-
Dimethyl-1,6-octadiene, 4-ethylidene-7
-Methyl-1,7-nonadiene, 4-ethylidene-8-
Methyl-1,7-nonadiene, 4-ethylidene-8-methyl-1,7-nonadiene, 4-ethylidene-8-methyl-1,8-decadiene, 4-ethylidene-9-methyl-1,8-decadiene, 4-ethylidene-9-methyl-
1,9-undecadiene, 4-ethylidene-10-methyl-1,9-undecadiene, 4-ethylidene-10-
Methyl-1,10-dodecadien, 4-ethylidene-1
1-methyl-1,10-dodecadiene, 4-ethylidene-12-methyl-1,11-tridecadiene, 4-ethylidene-13-methyl-1,11-tridecadienene,
-Ethylidene-12-methyl-1,12-tetradecadiene, 4-ethylidene-13-methyl-1,12-tetradecadiene, 4-ethylidene-13-methyl-1,1
Linear polyenes such as 3-pentadecadiene and 4-ethylidene-14-methyl-1,13-pentadecadiene are exemplified.

Further, in the following formula (I), X is-(C
R ⁴ ₂ ) N- (where R ⁴ is the same or different,
Represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, n represents a straight chain or branched alkylene group preferably represented by a is) an integer of from 1 to 10, especially - (CH ₂₎ n- (where , N is an integer of 1 to 10). Specifically, 4-methyl-1,4
-Hexadiene, 5-methyl-1,4-hexadiene,
5-methyl-1,5-heptadiene, 6-methyl-1,5
-Heptadiene, 6-methyl-1,6-octadiene,
7-methyl-1,6-octadiene, 5,7-dimethyl-
Examples thereof include 1,6-octadiene, 8-methyl-1,7-nonadiene, and 9-methyl-1,8-decadiene, and particularly preferably, 7-methyl-1,6-octadiene is used. These non-conjugated polyenes can be used alone or in combination of two or more.

Formula (I) CH ₂ ＣＨCH—X—CR ¹ ＣＲCR ² —R ³ (wherein X represents a saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, and R ¹ and R ² represent The same or different, and represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R ³ represents an alkyl group having 1 to 8 carbon atoms, unless R ¹ and R ² are both hydrogen atoms. )

(A) The iodine value of the ethylene copolymer rubber is in the range of 0.5 to 50, preferably 1 to 45 (the above requirement). In this case, if the iodine value is less than 0.5, the mechanical strength is poor, while if it exceeds 50, the rubber elasticity is impaired. Adjustment of the iodine value can be easily performed by adjusting the amount of the non-conjugated polyene or the like.

The ethylene copolymer rubber (A) preferably further has a unit derived from α, ω-diene represented by the following formula (II). Formula (II) CH ₂ ＣＨCH— (CH ₂ ) m—CH = CH ₂ (where m is an integer of 1 to 10.) Thus, α, ω-diene is combined to form (A) ethylene When a system-based copolymer rubber is produced, the molecular weight distribution of the obtained ethylene-based copolymer rubber (A) is appropriately widened and processability is improved. As the α, ω-diene, specifically,
1,5-hexadiene, 1,6-heptadiene, 1,7
-Octadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene, 1,12-tridecadiene, 1,13-tetradecadiene and the like, preferably 1,5-hexadiene, 1,7 -Octadiene, 1,9-decadiene and the like. These α,
ω-dienes can be used alone or in combination of two or more. (A) α, ω- of the above formula (II) is added to the ethylene copolymer rubber.
When units derived from ene are included, their content is
It is desirably 0.001 to 3 mol%, preferably 0.01 to 0.3 mol%.

Further, (A) the Mooney viscosity (ML1 + 4, 100 ° C.) of the ethylene copolymer rubber (hereinafter, also simply referred to as “Mooney viscosity”) is 20 to 350, preferably 3
It is in the range of 0 to 300 (the above requirements). If the Mooney viscosity is less than 20, the mechanical strength of the obtained rubber composition tends to decrease, while if it exceeds 350, processing of the obtained rubber composition becomes difficult.

Further, (A) a glass transition temperature T of ethylene copolymer rubber obtained by a differential scanning calorimeter (DSC).
g is −50 ° C. to −80 ° C., preferably −55 ° C. to −75 ° C.
It is in the range of ° C (the above requirement).

Further, (A) the molecular weight distribution of the ethylene copolymer rubber is determined by the ratio [Mw] between the weight average molecular weight (Mw) and the number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC). /
Mn (molecular weight distribution)] is preferably 2 to 15, and more preferably 3 to 10.

The (A) ethylene copolymer rubber used in the present invention can be produced by an appropriate method such as a gas phase polymerization method, a solution polymerization method, and a slurry polymerization method. These polymerization operations can be carried out in a batch system or a continuous system. In the above solution polymerization method or slurry polymerization method, an inert hydrocarbon is usually used as a reaction medium. Such inert hydrocarbon solvents include, for example,
Aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane, n-octane, n-decane, n-dodecane; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; benzene, toluene, xylene and the like Aromatic hydrocarbons and the like. These hydrocarbon solvents can be used alone or in combination of two or more. Further, the raw material monomer can be used as a hydrocarbon solvent.

Examples of the polymerization catalyst used for producing the (A) ethylene copolymer rubber include, for example, V, T
An olefin polymerization catalyst comprising a compound of a transition metal selected from i, Zr and Hf and an organometallic compound can be exemplified. The transition metal compound and the organometallic compound can be used alone or in combination of two or more. As a particularly preferred example of such an olefin polymerization catalyst, a metallocene catalyst comprising a metallocene compound and an organoaluminum compound or an ionic compound which reacts with the metallocene compound to form an ionic complex can be mentioned. Hereinafter, (A) a polymerization catalyst for producing an ethylene-based copolymer rubber will be described more specifically, but a polymerization catalyst other than the following may be used in some cases.

Examples of the above metallocene catalyst include, for example,
A catalyst comprising the following components (C) and (D) or a catalyst comprising the following components (E) and (F) is exemplified. Component (C) is a transition metal compound represented by the following general formula (1). R ″ _s (C ₅ R _m ) _p (R ′ _n E) _q MQ _4-pq (1) In the formula, M is a Group 4 metal of the periodic table, and (C ₅ R _m ) Is a cyclopentadienyl group or a substituted cyclopentadienyl group, and each R may be the same or different and includes a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, 7 is an alkaryl group having 7 to 40 or an aralkyl group having 7 to 40 carbon atoms, or two adjacent carbon atoms are bonded to form a 4- to 8-membered carbocyclic ring; R ′ is an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an alkaryl group having 7 to 40 carbon atoms, or an
40 is an aralkyl group, R '' is an alkylene group having 1 to 20 carbon atoms, dialkylsilicon or dialkylgermanium, which is a group binding two ligands,
Is 1 or 0; when s is 1, m is 4; n is a number smaller than the valence of E by 2; when s is 0, m is 5,
n is one less than the valence of E, and when n ≧ 2, each R ′ may be the same or different, each R ′ may be bonded to form a ring, and Q is a hydrogen atom A halogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an alkaryl group having 7 to 40 carbon atoms or an aralkyl group having 7 to 40 carbon atoms, and p and q are 0 to 4
And satisfies the relationship 0 <p + q ≦ 4.

Specific examples of component (C) include bis (cyclopentadienyl) zirconium dichloride, bis (cyclopentadienyl) zirconium dibromide, bis (cyclopentadienyl) zirconium dimethyl, bis (cyclopentadienyl) ) Zirconium diphenyl, dimethylsilylbis (cyclopentadienyl) zirconium dichloride, dimethylsilylbis (cyclopentadienyl) zirconium dimethyl, methylenebis (cyclopentadienyl) zirconium dichloride, ethylenebis (cyclopentadienyl) zirconium dichloride, bis (Indenyl) zirconium dichloride, bis (indenyl) zirconium dimethyl, dimethylsilylbis (indenyl) zirconium dichloride, methylenebis (indenyl) zircon Umujikurorido, bis (4,
5,6,7-tetrahydroindenyl) zirconium dichloride, bis (4,5,6,7-tetrahydroindenyl) zirconium dimethyl, dimethylsilylbis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, dimethyl Silyl bis (4,5,6,7
-Tetrahydroindenyl) zirconium dimethyl, ethylenebis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dimethyl, dimethylsilyl Bis (3-methyl-1-cyclopentadienyl)
Zirconium dichloride, methylene bis (3-methyl-
1-cyclopentadienyl) zirconium dichloride,
Bis (t-butylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (3-t-butyl-1
-Cyclopentadienyl) zirconium dichloride, bis (1,3-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (2,4-dimethyl-1-cyclopentadienyl) zirconium dichloride, bis (1,2,2 4-trimethylcyclopentadienyl) zirconium dichloride, dimethylsilylbis (2,3,5-trimethyl-1-cyclopentadienyl) zirconium dichloride, bis (fluorenyl) zirconium dichloride, dimethylsilylbis (fluorenyl) zirconium dichloride, ( Fluorenyl) (cyclopentadienyl) zirconium dichloride, dimethylsilyl (fluorenyl) (cyclopentadienyl) zirconium dichloride, isopropylene (fluorenyl) (cyclopentadiene Le) zirconium dichloride, (t-butylamido) (1,2,3,4,5-pentamethylcyclopentadienyl) zirconium dichloride, dimethylsilyl (t-butylamido) (2,3,
4,5-tetramethyl-1-cyclopentadienyl) zirconium dichloride, methylene (t-butylamide)
(2,3,4,5-tetramethyl-1-cyclopentadienyl) zirconium dichloride, (phenoxy)
(1,2,3,4,5-pentamethylcyclopentadienyl) zirconium dichloride, dimethylsilyl (o-phenoxy) (2,3,4,5-tetramethyl-1-cyclopentadienyl) zirconium dichloride, methylene (O-phenoxy) (2,3,4,5-tetramethyl-1-cyclopentadienyl) zirconium dichloride, ethylene (o-phenoxy) (2,3,4,5-tetramethyl-1-cyclopentadi (Enyl) zirconium dichloride, bis (dimethylamido) zirconium dichloride, bis (diethylamido) zirconium dichloride, bis (di-t-butylamido) zirconium dichloride, dimethylsilylbis (methylamido) zirconium dichloride, dimethylsilylbis (t-butylamide)
Examples include zirconium dichloride and the like, and compounds in which zirconium in these compounds is substituted with titanium or hafnium, but is not limited thereto. The transition metal compound may be used alone or
More than one species can be used in combination.

The component (D) is represented by the following general formula (2)
Is an aluminoxane compound having a unit represented by the following formula, and its chemical structure is not necessarily clear, but it is presumed to be a linear, cyclic or cluster compound, or a mixture of these compounds. -[Al (P) -O]-... (2) wherein P is an alkyl group having 1 to 20 carbon atoms, and 6 to 4 carbon atoms.
An aryl group having 0, an alkaryl group having 7 to 40 carbon atoms or an aralkyl group having 7 to 40 carbon atoms, preferably a methyl group, an ethyl group, an isobutyl group, and particularly preferably a methyl group. The aluminoxane compound can be produced by a known method involving a reaction between water and the organoaluminum compound having at least one P group.
The ratio of the components (C) and (D) used is usually from 1/1 to 1 / 100,000, preferably from 1 to 100,000 in terms of the molar ratio of the transition metal to the aluminum atom (transition metal / aluminum atom). / 5 to 1 / 50,000.

Next, the component (E) is a transition metal alkyl compound represented by the following general formula (3). R ″ _S (C ₅ R _m ) _p (R ′ _n E) _q MR ″ ′ _4-pq (3) In the formula, M is a Group 4 metal of the periodic table, and (C ₅ R _m ) is a cyclopentadienyl group or a substituted cyclopentadienyl group, and each R may be the same or different and includes a hydrogen atom,
An alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 40 carbon atoms, an alkaryl group having 7 to 40 carbon atoms or 7 carbon atoms
４０40 aralkyl groups, or two adjacent carbon atoms combine to form a 4- to 8-membered carbocycle;
E is an atom having a non-bonded electron pair, and R ′ has 1 carbon atom.
An alkyl group having from 20 to 20 carbon atoms, an aryl group having from 6 to 40 carbon atoms, an alkaryl group having from 7 to 40 carbon atoms or an aralkyl group having from 7 to 40 carbon atoms, and R ″ is an alkylene group having from 1 to 20 carbon atoms, a dialkyl group. Silicon or dialkylgermanium, which is a group connecting two ligands, s is 1 or 0, and when s is 1, m is 4, n is 2 less than the valence of E; , S is 0, m is 5, n is E
Is less than the valence of n. When n ≧ 2, each R ′ may be the same or different, each R ′ may be bonded to form a ring, and R ′ ″ is the number of carbon atoms. An alkyl group of 1 to 20, an aryl group of 6 to 40 carbon atoms, an alkaryl group of 7 to 40 carbon atoms or an aralkyl group of 7 to 40 carbon atoms, p and q are integers of 0 to 3, and 0 <p +
The relationship of q ≦ 4 is satisfied.

Specific examples of component (E) include bis (cyclopentadienyl) zirconium dimethyl, bis (cyclopentadienyl) zirconium diethyl, bis (cyclopentadienyl) zirconium diisobutyl, and bis (cyclopentadienyl) Zirconium diphenyl, bis (cyclopentadienyl) zirconium di {bis (trimethylsilyl) methyl}, dimethylsilylbis (cyclopentadienyl) zirconium dimethyl, dimethylsilylbis (cyclopentadienyl) zirconium diisobutyl, methylenebis (cyclopentadienyl) ) Zirconium dimethyl, ethylene bis (cyclopentadienyl) zirconium dimethyl, bis (indenyl) zirconium dimethyl, bis (indenyl) zirconium diisobutyl, dimethyl Rubis (indenyl) zirconium dimethyl, methylenebis (indenyl) zirconium dimethyl, ethylenebis (indenyl) zirconium dimethyl, bis (4,5,6,7-tetrahydroindenyl) zirconium dimethyl, dimethylsilylbis (4,5,6,7 -Tetrahydro-1-indenyl) zirconium dimethyl, ethylenebis (4,5,6,7-
Tetrahydro-1-indenyl) zirconium dimethyl, bis (methylcyclopentadienyl) zirconium dimethyl, dimethylsilylbis (3-methyl-1-cyclopentadienyl) zirconium dimethyl, bis (t-
Butylcyclopentadienyl) zirconium dimethyl,
Dimethylsilylbis (3-t-butyl-1-cyclopentadienyl) zirconium dimethyl, bis (1,3-dimethylcyclopentadienyl) zirconium dimethyl,
Bis (1,3-dimethylcyclopentadienyl) zirconium diisobutyl, dimethylsilylbis (2,4-dimethyl-1-cyclopentadienyl) zirconium dimethyl, methylenebis (2,4-dimethyl-1-cyclopentadienyl) Zirconium dimethyl, ethylene bis (2,4-dimethyl-1-cyclopentadienyl) zirconium dimethyl, bis (1,2,4-trimethylcyclopentadienyl) zirconium dimethyl, dimethylsilylbis (2,3,5-trimethyl) -1-cyclopentadienyl) zirconium dimethyl, bis (fluorenyl) zirconium dimethyl, dimethylsilylbis (fluorenyl) zirconium dimethyl, (fluorenyl)
(Cyclopentadienyl) zirconium dimethyl, dimethylsilyl (fluorenyl) (cyclopentadienyl)
Zirconium dimethyl, isopropylene (fluorenyl) (cyclopentadienyl) zirconium dimethyl,
(T-butylamide) (1,2,3,4,5-pentamethylcyclopentadienyl) zirconium dimethyl, dimethylsilyl (t-butylamide) (2,3,4,5-
Tetramethyl-1-cyclopentadienyl) zirconium dimethyl, methylene (t-butylamide) (2,3
4,5-tetramethyl-1-cyclopentadienyl) zirconium dimethyl, (phenoxy) (1,2,3
4,5-pentamethylcyclopentadienyl) zirconium dimethyl, dimethylsilyl (o-phenoxy)
(2,3,4,5-tetramethyl-1-cyclopentadienyl) zirconium dimethyl, methylene (o-phenoxy) (2,3,4,5-tetramethyl-1-cyclopentadienyl) zirconium dimethyl, Bis (dimethylamido) zirconium dimethyl, bis (diethylamido) zirconium dimethyl, bis (di-t-butylamido) zirconium dimethyl, dimethylsilylbis (methylamido) zirconium dimethyl, dimethylsilylbis (t-butylamido) zirconium dimethyl Compounds obtained by substituting zirconium therein with titanium or hafnium include, but are not limited to. The above transition metal alkyl compounds can be used alone or in combination of two or more.

The transition metal alkyl compound may be synthesized and used in advance, or may be a transition metal halide in which R ″ in the above general formula (III) is substituted with a halogen atom, and trimethylaluminum, triethylaluminum, diethyl It may be formed by bringing an organometallic compound such as aluminum monochloride, triisobutylaluminum, methyllithium, or butyllithium into contact in a reaction system.

The component (F) is an ionic compound represented by the following general formula (4). ([L] k ⁺ ) p ([M′A1A2... An] ⁻ ) q (4) wherein [L] k ⁺ is a Bronsted acid or a Lewis acid; 'Is a group 13 to 15 element of the periodic table,
1 to An each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a dialkylamino group having 1 to 30 carbon atoms, an alkoxyl group having 1 to 20 carbon atoms,
40 aryl groups, C6 to C40 aryloxy groups, C7 to C40 alkaryl groups, C7 to C40
An aralkyl group, a halogen-substituted hydrocarbon group having 1 to 40 carbon atoms, an acyloxy group or an organic metalloid group having 1 to 20 carbon atoms, k is an ionic value of L, an integer of 1 to 3, and p is 1 or more. And q = (k × p).

Specific examples of component (F) include trimethylammonium tetraphenylborate, triethylammonium tetraphenylborate, tri-n-butylammonium tetraphenylborate, methyl (di-n-butyl) ammonium tetraphenylborate, tetraphenylammonium Dimethylanilinium borate, methylpyridinium tetraphenylborate, methyl tetraphenylborate (2-
Cyanopyridinium), methyl tetraphenylborate (4-cyanopyridinium), trimethylammonium tetrakis (pentafluorophenyl) borate, triethylammonium tetrakis (pentafluorophenyl) borate, tri-n-butylammonium tetrakis (pentafluorophenyl) borate, tetrakis Methyl (penta-fluorophenyl) borate (di-n-butyl) ammonium, dimethylanilinium tetrakis (pentafluorophenyl) borate, methylpyridinium tetrakis (pentafluorophenyl) borate, methyl (2-cyanopyridinium) tetrakis (pentafluorophenyl) borate ), Methyl tetrakis (pentafluorophenylphenyl) borate (4-cyanopyridinium),
Dimethylanilinium tetrakis [3,5-di- (trifluoromethyl) phenyl] borate, ferrocenium tetraphenylborate, silver tetraphenylborate, ferrocenium tetrakis (pentafluorophenyl) borate, and the like, but are not limited thereto. is not. The above ionic compounds can be used alone or in combination of two or more.

The above component (E) and component (F) are used in a molar ratio [(E) / (F)] of usually 1 / 0.5 to 0.5.
1/20, preferably in the range of 1 / 0.8 to 1/10. (A) The metallocene-based catalyst used when producing the ethylene-based copolymer rubber may be used by supporting at least a part of those components on a suitable carrier. There is no particular limitation on the type of carrier, inorganic oxide carrier,
Any of other inorganic carriers and organic carriers can be used. In addition, there is no particular limitation on the loading method, and a known method may be appropriately used.

Next, among the vulcanizing agents and / or crosslinking agents (B) used in the present invention, examples of the vulcanizing agent include sulfur such as powdered sulfur, precipitated sulfur, colloidal sulfur and insoluble sulfur; sulfur chloride; , Selenium, tellurium and other inorganic vulcanizing agents;
Examples include sulfur-containing organic compounds such as morpholine disulfide, alkylphenol disulfides, thiuram disulfides, and dithiocarbamates. These vulcanizing agents can be used alone or in combination of two or more.

The amount of the vulcanizing agent is usually 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the ethylene copolymer rubber (A).

Incidentally, a vulcanization accelerator can be used together with the above vulcanizing agent. Examples of such a vulcanization accelerator include aldehyde ammonias such as hexamethylenetetramine; guanidines such as diphenylguanidine, di (o-tolyl) guanidine and o-tolyl-piguanide; thiocarbanilide and di (o-tolyl) Thioureas such as thiourea, N, N'-diethylthiourea, tetramethylthiourea, trimethylthiourea, dilaurylthiourea; mercaptobenzothiazole, dibenzothiazole disulfide, 2- (4-morpholinothio) benzothiazole, 2- (2,4-dinitrophenyl) -mercaptobenzothiazole, (N, N'-
Thiazoles such as diethylthiocarbamoylthio) benzothiazole; Nt-butyl-2-benzothiazylsulfenamide, N, N'-dicyclohexyl-2-
Sulfenamides such as benzothiazylsulfenamide, N, N'-diisopropyl-2-benzothiazylsulfenamide, N-cyclohexyl-2-benzothiazylsulfenamide; tetramethylthiuram disulfide, tetraethylthiuram disulfide , Tetra-
Thiurams such as n-butylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylenethiuram tetrasulfide; zinc dimethylthiocarbamate, zinc diethylthiocarbamate, zinc di-n-butylthiocarbamate, zinc ethylphenyldithiocarbamate And carbamates such as sodium dimethyldithiocarbamate, copper dimethyldithiocarbamate, tellurium dimethylthiocarbamate and iron dimethylthiocarbamate; and xanthates such as zinc butylthioxanthate. These vulcanization accelerators can be used alone or in combination of two or more.

The compounding amount of the vulcanization accelerator is usually 0.1 to 20 parts by weight based on 100 parts by weight of (A) the ethylene copolymer rubber.
Parts by weight, preferably 0.2 to 10 parts by weight.

[0031] In addition to the above vulcanizing agents and vulcanization accelerators, vulcanization accelerating auxiliaries can be added, if necessary. Examples of such vulcanization accelerating aids include metal oxides such as magnesium oxide, zinc white, litharge, leadtan, and lead white; organic acids (salts) such as stearic acid, oleic acid, and zinc stearate. And zinc white and stearic acid are particularly preferred. These vulcanization accelerators can be used alone or in combination of two or more. The compounding amount of the vulcanization accelerator is (A) ethylene copolymer rubber 1
It is usually 0.5 to 20 parts by weight with respect to 00 parts by weight.

On the other hand, as the crosslinking agent constituting the component (B), for example, 1,1-di-tert-butylperoxy-3,
3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 1,3-bis (t Organic peroxides such as -butylperoxy-isopropyl) benzene. These crosslinking agents can be used alone or in combination of two or more. The compounding amount of the crosslinking agent is usually 0.1 to 15 parts by weight, preferably 0.5 to 100 parts by weight of the ethylene copolymer rubber (A).
To 10 parts by weight.

It should be noted that a crosslinking aid may be used in combination with the crosslinking agent. Examples of such a crosslinking assistant include sulfur and sulfur compounds such as sulfur and dipentamethylenethiuram tetrasulfide; ethylene di (meth)
Acrylate, polyethylene di (meth) acrylate,
Examples include polyfunctional monomers such as divinylbenzene, diallyl phthalate, triallyl cyanurate, metaphenylene bismaleimide, and toluylene bismaleimide; and oxime compounds such as p-quinone oxime and p, p'-benzoylquinone oxime. These crosslinking assistants can be used alone or in combination of two or more. The compounding amount of the crosslinking aid is usually 0.5 to 20 parts by weight based on 100 parts by weight of the ethylene copolymer rubber (A).

The rubber composition of the present invention may contain, if necessary, a plasticizer, a lubricant, a filler, a softener, and a foaming agent.
Various other additives such as a tackifier, an antioxidant, and an ultraviolet absorber can be added.

As the filler, for example, SRF, G
PF, FEF, HAF, ISAF, SAF, FT, MT
Inorganic fillers such as carbon black, white carbon, fine particle magnesium silicate, heavy calcium carbonate, magnesium carbonate, clay, talc, etc .; high styrene resin, coumarone indene resin, phenol resin, lignin, modified melamine resin, petroleum An organic filler such as a resin can be used. These fillers can be used alone or in combination of two or more. The amount of the filler is usually 10 to 200 parts by weight, preferably 10 to 1 part by weight, per 100 parts by weight of the ethylene copolymer rubber (A).
00 parts by weight.

Examples of the softener include process oils such as aromatic oils, naphthenic oils and paraffin oils, vegetable oils such as coconut oil, and the like, which are commonly used for rubber.
And synthetic oils such as alkylbenzene oils. Of these, process oils are preferred, and paraffin oil is particularly preferred. The softener may be used alone or
A mixture of more than one species can be used. In the present invention, the compounding amount of the softening agent is usually 10 to 130 parts by weight, preferably 20 to 100 parts by weight, based on 100 parts by weight of the ethylene copolymer rubber (A).

Examples of the foaming agent include inorganic foaming agents such as ammonium carbonate, sodium bicarbonate and anhydrous sodium nitrate, dinitrosopentamethylenetetramine,
N, N'-dimethyl-N, N'-dinitrosoterephthalamide, benzenesulfonyl hydrazide, p, p'-oxybis (benzenesulfonyl hydrazide), 3,3 '
Organic blowing agents such as disulfone hydrazide diphenyl sulfone, azobisisobutyronitrile, azobisformamide. In addition, along with these blowing agents,
A foaming aid such as a urea-based, organic acid-based, or metal salt-based may be used in combination. These foaming agents and foaming assistants can be used alone or in combination of two or more.

Further, in the rubber composition of the present invention, one or more of other rubbers and / or resins can be mixed and used.

In preparing the rubber composition of the present invention, a conventionally known kneading machine, extruder, vulcanizing apparatus and the like can be used. The compounding method and order of the vulcanizing agent and / or crosslinking agent, filler, softener and the like mixed together with the ethylene copolymer rubber may be, for example, using a Banbury mixer, etc. , A softening agent and the like, and then adding a vulcanizing agent and / or a crosslinking agent using a roll or the like, but is not limited thereto.

Next, vulcanization is carried out by, for example, placing the rubber composition of the present invention in a mold and raising the temperature, or vulcanizing by means of an extrusion molding machine. And vulcanization by heating in a vulcanization tank and vulcanizing, whereby a vulcanized rubber can be produced.

The rubber composition of the present invention is excellent in anti-vibration properties and compression set.
It is suitably used for vibration-proof rubber applications for precision equipment such as storage devices such as D-ROMs and audio products such as vehicle-mounted and portable CDs. It is also suitable as a vibration-proof rubber for machines, home appliances, civil engineering materials, automobile vehicles, and the like.

[0042]

The present invention will now be described more specifically with reference to examples. However, the present invention is not limited to these embodiments. The percentages and parts in the examples are on a weight basis unless otherwise specified. The measurement and evaluation in Examples and Comparative Examples were performed by the following methods.

(A) α-Olefin content (mol%) Measured by ¹³ C-NMR method. However, the content (mol%) of ethylene and 1-butene in each of Examples and Comparative Examples is a value when the total amount thereof is 100 mol%. (Ii) Iodine value It was measured by an infrared absorption spectrum method. (C) Mooney viscosity (ML1 + 4, 100 ° C.) Measured at 100 ° C., 1 minute of preheating, and 4 minutes of measurement in accordance with JIS K6300. (D) It was measured by GPC in Mw / Mn o-dichlorobenzene at 135 ° C. (E) Glass transition temperature (Tg) Using a 910 type differential scanning calorimeter manufactured by DuPont Instruments (currently TIA Instruments), the sample was heated to 180 ° C., and then 10 ° C. The temperature was measured at a rate of 20 ° C./min after cooling to −90 ° C./min.

(F) Tensile test According to JIS K6301, using a No. 3 type test piece at a measuring temperature of 25 ° C. and a tensile speed of 500 mm / min, a tensile strength TB (MPa) and an elongation at break EB ( %) Was measured. (G) Hardness test According to JIS K6301, the spring hardness (JIS
A hardness). (H) Compression set In accordance with JIS K6301, the compression set was measured at 70 ° C. for 22 hours. (I) tan δ The tan δ was measured using a viscoelastic spectrometer manufactured by Iwamoto Seisakusho under the conditions of 5% static strain, 0.5% dynamic strain, 5 Hz, and 25 ° C.

Synthesis Example 1 (Production of Ethylene Copolymer Rubber) Into a stainless steel autoclave having an internal capacity of 3 liters sufficiently purged with nitrogen, 1.3 liters of purified toluene and 1-liter
After adding 600 ml of butene, 50 ml of 7-methyl-1,6-octadiene and 60 normal liters of ethylene, the temperature in the vessel was adjusted to 30 ° C. Separately, dimethylsilyl (t-butylamide) (2,3,4) dissolved in 3.0 ml of purified toluene was placed in a 50 ml-content glass flask containing a magnetic stirrer and sufficiently purged with nitrogen. 2,5-tetramethyl-1-cyclopentadienyl) titanium dichloride (2.0 μmol) and triisobutylaluminum (1.0 mmol) dissolved in 6.0 ml of purified toluene were added, and the mixture was stirred at room temperature for 30 minutes to react. Was. Next, 4.0 μmol of dimethylanilinium tetrakis (pentafluorophenyl) borate dissolved in 7.2 ml of purified toluene was added, and the mixture was stirred at room temperature for 20 minutes to be reacted to obtain a polymerization catalyst.

The polymerization catalyst was added to the above autoclave to initiate polymerization. During the polymerization, the temperature was maintained at 30 ° C., and the polymerization was performed for 15 minutes. Next, after a small amount of methanol was added to stop the reaction, the mixture was dissolved by steam stripping and dried with a 6-inch roll to obtain 85 g of a polymer. This polymer has an ethylene unit content of 4
0.5 mol, 1-butene unit content: 59.5 mol, iodine value: 19.5, Mooney viscosity: 45, Mw / Mn:
2.4, Tg: ethylene / 1-butene / -60.5 ° C.
It was a 7-methyl-1,6-octadiene copolymer rubber. Table 1 shows the analysis results of the rubber.

Synthesis Example 2 In Synthesis Example 1, 1,9-decadiene, which is an α, ω-diene, together with 7-methyl-1,6-octadiene was added to 0.1.
A copolymer rubber of Synthesis Example 2 was obtained in the same manner as in Synthesis Example 1 except that 01 mol was added. Table 1 shows the analysis results.

Synthesis Examples 3 to 5 Either changing the ethylene / 1-butene ratio (Synthesis Example 3) or EPDM using propylene as the α-olefin
(Synthesis Example 4) or EPDM using 1-octene as an α-olefin (Synthesis Example 5), in the same manner as in Synthesis Example 1, except that The rubber of Example 5 was obtained. Table 1 shows the analysis results.

[0049]

[Table 1] A: 7-methyl-1,6-octadiene B: 1,9-decadiene

Example 1 (Preparation and Evaluation of Rubber Composition) Using the copolymer rubber of Synthesis Example 1, components other than the vulcanizing agent component from the compounding components shown in Table 2 were banbury (content 250
Milliliter) at a rotational speed of 60 rpm at 60 ° C.
Compound (i) was obtained by kneading for 50 seconds. Next, the vulcanizing agent components shown in Table 1 were added to the compound (i), and the mixture was kneaded with a 4-inch roll maintained at 50 ° C. for 5 minutes to obtain a compound (ii). Next, the compound (ii) was heated by a hot press heated to 160 ° C. under a pressure of 150 kgf / cm ² for 30 minutes to produce a vulcanized sheet of 120 × 120 × 2 mm, and various characteristics were obtained. evaluated. Table 3 shows the results.

Comparative Examples 1-3 Vulcanized sheets were prepared in the same manner as in Example 1 except that the copolymer rubbers obtained in Synthetic Examples 3, 4, and 5 were used, and various characteristics were evaluated. . Table 3 shows the results.

[0052]

[Table 2] * 1) Seast # 116 (Tokai Carbon) * 2) PW-380 (Idemitsu Kosan) * 3) Mercaptobenzothiazole (Ouchi Emerging) * 4) Tetramethylthiuram disulfide (Ouchi Emerging)

[0053]

[Table 3]

From the results shown in Table 3, the following is clear. The rubber compositions (Examples 1 and 2) of the present invention have mechanical properties (TB, EB), compression set (C
S), and has excellent anti-vibration properties (tan δ), and various properties are balanced to a high level. On the other hand, Comparative Example 1 is a case where the molar ratio of ethylene / 1-butene is out of the range of the present invention as the copolymer rubber, and is inferior in anti-vibration properties. Comparative Example 2 is a case where EPDM obtained by copolymerizing propylene was used as the copolymer rubber, and was also inferior in compression set and anti-vibration properties. Comparative Example 3 is a case where an ethylene copolymer rubber obtained by copolymerizing 1-octene was used as the copolymer rubber, and was excellent in vibration-proof properties and compression set, but was inferior in mechanical properties.

[0055]

The rubber composition of the present invention has a relatively low hardness, excellent mechanical properties, vibration-proof properties and compression set,
It is well-balanced to a high level and is useful for various anti-vibration rubber applications.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16F 15/08 F16F 15/08 D (72) Inventor Kenji Hasegawa 2-1-24-1 Tsukiji, Chuo-ku, Tokyo Inside JSR Co., Ltd.

Claims (3)

[Claims] (A) a unit derived from ethylene, 1-
It has a unit derived from butene and a unit derived from a non-conjugated polyene, and contains, as main components, an ethylene copolymer rubber satisfying the following requirements and (B) a vulcanizing agent and / or a crosslinking agent. A rubber composition for anti-vibration rubber, characterized by: Requirements The molar ratio (ethylene / 1-butene) of the unit derived from ethylene to the unit derived from 1-butene is 20/80.
８５85/15 Iodine value 0.5 ニ ー 50 Mooney viscosity (ML1 + 4, 100 ° C.) 20２０350
The glass transition temperature (Tg) determined by a differential scanning calorimeter (DSC) is −50 ° C. to −80 ° C. 2. The anti-vibration rubber according to claim 1, wherein the non-conjugated polyene in the (A) ethylene copolymer rubber is a linear non-conjugated polyene represented by the following formula (I). Rubber composition. Formula (I) CH ₂ ＣＨCH—X—CR ¹ ＣＲCR ² —R ³ (wherein, X represents a saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, and R ¹ and R ² are the same or different. Differently, it represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R ³ represents an alkyl group having 1 to 8 carbon atoms, except that both R ¹ and R ² are hydrogen atoms.) 3. An anti-vibration rubber according to claim 2, wherein (A) the ethylene copolymer rubber further comprises a unit derived from α, ω-diene represented by the following formula (II). Rubber composition. Formula _{(II) CH 2 = CH- (} CH 2) m-CH = CH 2 ( wherein, m is an integer of from 1 to 10.)