JPH08134140A - Ethylene-based copolymer, its composition and its crosslinked rubber - Google Patents

Abstract

PURPOSE: To obtain a new ethylene-based copolymer excellent in property processed by roll, dynamic characteristics, etc., having high physical balance and capable of applying to an ethylene-based crosslinked rubber. CONSTITUTION: This ethylene-based copolymer comprises a random copolymer composed of ethylene, an α-olefine, an aromatic vinyl compound and a non- conjugated diene and has (30/70) to (90/10) molar ratio of ethylene to α-olefin, 0.01-30mol% of an aromatic vinyl compound content, 0.1-30mol% of a nonconjugated diene content and 15-150 Mooney viscosity at 100 deg.C.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an ethylene copolymer, a composition thereof and a crosslinked rubber thereof.

[0002]

2. Description of the Prior Art Ethylene / α-olefin / aromatic vinyl compound copolymers have been proposed in the following series of prior art documents. That is, Japanese Patent Application Laid-Open No. 3-250007 discloses a method for producing an alternating copolymer of ethylene and styrene having an isotactic structure by using a catalyst system composed of a specific transition metal compound and aluminoxane. Further, in JP-A-3-163088, a catalyst composed of a constrained geometry complex and an aluminoxane is used.
A method for producing an α-olefin / styrene copolymer with high activity is shown. Similarly, Japanese Patent Laid-Open No. 5-194641
The publication discloses an example of the synthesis of an ethylene / propylene / styrene copolymer using a catalyst obtained by contacting a constrained geometry complex with a Lewis acid. Further, JP-A-6-49
Japanese Patent No. 132 discloses a method for producing an ethylene / styrene copolymer by using a catalyst composed of a specific transition metal compound and aluminoxane.

An ethylene / propylene / non-conjugated diene copolymer is known as a raw material for olefin rubber (EPDM). EPDM is excellent in heat resistance, weather resistance, ozone resistance and cold resistance, and although it is used in various fields, it is known that it is inferior in roll processability and low temperature setting property.

At present, EPDM is industrially produced using a vanadium catalyst or a titanium catalyst. In recent years, a method for producing EPDM using a metallocene catalyst has also been shown. For example, JP-A-62-121711 discloses a method for producing EPDM which uses a catalyst composed of a metallocene compound and an aluminoxane, has a narrow molecular weight distribution and composition distribution, and is excellent in transparency, non-adhesiveness and mechanical properties. Has been done.

As mentioned above, ethylene /
Although terpolymers such as α-olefin / non-conjugated dienes and ethylene / α-olefin / aromatic vinyl compounds have been reported, they have been reported as ethylene / α-olefin / aromatic vinyl compounds / non-conjugated dienes. No such quaternary copolymer has been reported yet.

[0006]

The present invention is based on the EPD
It is an object of the present invention to improve the roll processability and low temperature settability, which are problems of M, and to provide an ethylene copolymer which can be applied to a crosslinked rubber having excellent mechanical properties.

[0007]

The present invention is a random copolymer composed of ethylene, α-olefin, aromatic vinyl compound and non-conjugated diene, which is applicable to crosslinked rubber and the like. Olefin molar ratio is 30 /
70 to 90/10, an aromatic vinyl compound content of 0.01 to 30 mol% and a non-conjugated diene content of 0.1 to 30 mol%. Polymer, ethylene-based copolymer composition comprising the ethylene-based copolymer and sulfur and / or organic peroxide, ethylene-based copolymer obtained by crosslinking the ethylene-based copolymer with sulfur and / or organic peroxide The main point is a united crosslinked rubber.

The details will be described below.

The α-olefin constituting the copolymer of the present invention has a carbon number of 3 or more, such as propylene,
1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1
-Tridecene, 1-tetradecene, 1-pentadecene,
1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicodecene and the like,
These 1 type (s) or 2 or more types are used. Among them, propylene, 1-butene, 1-heptene, 1-hexene, 1-octene and the like are preferable because of easy availability.

As the aromatic vinyl compound constituting the copolymer of the present invention, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o, p
-Dimethyl styrene, o-ethyl styrene, m-ethyl styrene, p-ethyl styrene, o-chloro styrene,
Examples thereof include p-chlorostyrene and α-methylstyrene.

As the non-conjugated diene constituting the copolymer of the present invention, 1,4-pentadiene, 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 5-isopropenyl-2-norbornene,
2,5-norbornadiene, 1,6-cyclooctadiene, 1,7-octadiene, tricyclopentadiene and dihydrodicyclopentadienyloxyethylene and acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, etc. Examples thereof include esters with unsaturated carboxylic acids, but are not limited thereto.

The ethylene copolymer of the present invention has the following composition and properties.

(A) The molar ratio of ethylene to α-olefin is in the range of 30/70 to 90/10, particularly 45/5.
The range of 5 to 85/15 is preferable from the viewpoint of rubber performance and improvement of cold resistance.

(B) The aromatic vinyl compound content is 0.01
To 30 mol%, and particularly preferably 0.1 to 15 mol%. When the content of the aromatic vinyl compound is less than 0.01 mol%, the surface non-adhesiveness and roll processability are poor, and when it is more than 30 mol%, the glass transition point is increased, the low temperature characteristics are deteriorated, and the catalytic activity is lowered. However, there is a disadvantage in terms of composition.

(C) The content of the non-conjugated diene is in the range of 0.1 to 30 mol%, preferably 0.1 to 10 mol%. Non-conjugated diene content is 0.1 mol%
If it is less, the crosslinking rate will be slower, and if it is more than 30 mol%, the glass transition point will rise and the low temperature characteristics will be deteriorated.

Ethylene / α-used in the present invention
The Mooney viscosity at 100 ° C. of the olefin / aromatic vinyl compound / non-conjugated diene copolymer is 15 to 150.
It is preferably in the range of. This Mooney viscosity is 15
If it exceeds 0, the mechanical properties will become small, while if the Mooney viscosity is less than 15, the fluidity will decrease and the molding process may become difficult.

When this is replaced by the molecular weight, the number average molecular weight measured by gel permeation chromatography (GPC) is 5000 in terms of polyethylene.
Is 1,000,000, and the number average molecular weight is 5,000.
If it is less than 1, the mechanical properties will be small. On the other hand, if the number average molecular weight exceeds 1,000,000, the fluidity may be lowered, and molding process may become difficult.

The method for producing the above-mentioned ethylene / α-olefin / aromatic vinyl compound / non-conjugated diene copolymer is not particularly limited, and various catalysts such as titanium-based catalysts, vanadium-based catalysts and metallocene-based catalysts are used. Can be manufactured. Above all, it is preferable to use a metallocene catalyst having an excellent copolymerizability for the production by the following method. By this method, it is possible to obtain a copolymer having a narrow molecular weight distribution and a narrow composition distribution.

That is, an organic transition metal compound component containing a cyclopentadienyl derivative, a compound which reacts with this to form an ionic complex, and, if necessary, ethylene in the presence of a catalyst comprising an organic metal component, By copolymerizing the α-olefin, the aromatic vinyl compound and the non-conjugated diene, an ethylene / α-olefin / aromatic vinyl compound / non-conjugated diene copolymer can be produced.

Here, the organic transition metal compound component containing the catalyst cyclopentadienyl derivative is represented by the following general formula (1) or (2):

[0021]

Embedded image

(In the formula, Cp is a cyclopentadienyl group or a substitution product thereof, Z is an alkylene group or a silanediyl group, Y is a ligand containing nitrogen, phosphorus, oxygen or sulfur, and R, R'is independently a halogen atom, a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and M '
Is a titanium atom or a zirconium atom)

[0023]

Embedded image

(In the formula, Cp ¹ and Cp ² are each independently a cyclopentadienyl group, an indenyl group, a fluorenyl group, or a substitution product thereof, and R ¹ and R ² are each independently hydrogen, halogen or A hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group or an aryloxy group, M is a titanium atom, a zirconium atom or a hafnium atom, and R is
³ is an alkylene group or a silanediyl group which acts to crosslink Cp ¹ and Cp ² ).

Specific examples of the compound represented by the formula (1) include (dimethyl (t-butylamide) (tetramethyl-
η5-Cyclopentadienyl) silane) dichloride zirconium, (dimethyl (t-butylamide) (tetramethyl-η5-cyclopentadienyl) silane) dibenzylzirconium, (dimethyl (t-butylamide))
(Tetramethyl-η5-cyclopentadienyl) silane) dichloride titanium, (dimethyl (t-butylamide) (tetramethyl-η5-cyclopentadienyl) silane) dibenzyltitanium, (dimethyl (t-butylamide) (tetramethyl -Η5-cyclopentadienyl) silane) dimethyl titanium, ((t-butylamido) (tetramethyl-η5-cyclopentadienyl) -1,2-ethanediyl) dimethylzirconium, ((t-butylamido) (tetramethyl- η5-cyclopentadienyl)
-1,2-ethanediyl) dibenzyltitanium, ((methylamido) (η5-cyclopentadienyl) -1,2-
Ethanediyl) dibenzhydrylzirconium, ((methylamido) (tetramethyl-η5-cyclopentadienyl) -1,2-ethanediyl) dineopentyl titanium, ((phenylphosphide)-(tetramethyl-η5
-Cyclopentadienyl) methylene) diphenyl titanium, (dibenzyl (t-butylamido) (tetramethyl-η5-cyclopentadienyl) silane) dibenzylzirconium, (dimethyl (benzylamido) (η5-cyclopentadienyl) silane ) Di (trimethylsilyl)
Titanium, (dimethyl (phenylphosphide) (tetramethyl-η5-cyclopentadienyl) silane) dibenzylzirconium, (dimethyl (t-butylamido) (tetramethyl-η5-cyclopentadienyl) silane) dibenzylhafnium, ((Tetramethyl-η5-cyclopentadienyl) -1,2-ethanediyl) dibenzyltitanium, (2-η5- (Tetramethylcyclopentadienyl) -1-methyl-ethanolate (2-)) dibenzyltitanium , (2-η5- (Tetramethylcyclopentadienyl) -1-methyl-ethanolate (2-)) dimethyltitanium, (2-η5- (Tetramethylcyclopentadienyl) -1-methyl-ethanolate (2- )) Dibenzylzirconium, (2-η5- (tetramethylcyclopentadienyl) -1 Methyl - ethanolate (2
-)) Dimethyl zirconium, (2-((4a, 4b,
8a, 9,9a, -η) -9H-fluoren-9-yl) cyclohexanolate (2-)) dimethyl titanium,
(2-((4a, 4b, 8a, 9, 9a, -η) -9H
-Fluoren-9-yl) cyclohexanolate (2
-)) Dibenzyl titanium, (2-((4a, 4b, 8
a, 9,9a, -η) -9H-fluoren-9-yl)
Cyclohexanolate (2-)) dimethyl zirconium, and (2-((4a, 4b, 8a, 9,9a,-
η) -9H-fluoren-9-yl) cyclohexanolate (2-)) dibenzylzirconium, and the like, but are not limited thereto.

Specific examples of the compound represented by the formula (2) include ethylenebis (indenyl) zirconium dichloride, isopropylidene (cyclopentadienyl-1-fluorenyl) zirconium dichloride, dimethylsilanediylbis (2,4). , 5-Trimethylcyclopentadienyl) zirconium dichloride, dimethylsilanediylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilanediylbis (3-methylcyclopentadienyl) zirconium dichloride, dimethylsilanediylbis (4-t-
Butyl, 2-methylcyclopentadienyl) zirconium dichloride, diethylsilanediylbis (2,4,4)
5-trimethylcyclopentadienyl) zirconium dichloride, diethylsilanediylbis (2,4-dimethylcyclopentadienyl) zirconium dichloride, diethylsilanediylbis (3-methylcyclopentadienyl) zirconium dichloride, diethylsilanediylbis ( 4-t-butyl, 2-methylcyclopentadienyl) zirconium dichloride, diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride, methylphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride, isopropylidene (cyclo) Pentadienyl)
(2,7-di-methylfluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl)
(2,7-di-t-butylfluorenyl) zirconium dichloride, phenylmethylene (cyclopentadienyl) (2,7-di-methylfluorenyl) zirconium dichloride, diphenylmethylene (cyclopentadienyl) (2 , 7-Di-t-butylfluorenyl) zirconium dichloride, methylphenylmethylene (cyclopentadienyl) (2,7-di-methylfluorenyl)
Zirconium dichloride, methylphenylmethylene (cyclopentadienyl) (2,7-di-t-butylfluorenyl) zirconium dichloride, isopropylidenebis (cyclopentadienyl) zirconium dichloride, diphenylmethylenebis (cyclopentadienyl) Zirconium dichloride, methylphenylmethylene bis (cyclopentadienyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (tetramethylcyclopentadienyl) zirconium dichloride, diphenylmethylene (cyclopentadienyl)
(Tetramethylcyclopentadienyl) zirconium dichloride, isopropylidenebis (indenyl) zirconium dichloride, diphenylmethylenebis (indenyl) zirconium dichloride, methylphenylmethylenebis (indenyl) zirconium dichloride, etc. and organic transitions in which zirconium is replaced by titanium or hafnium Examples thereof include metal compounds, but are not limited thereto.

Any compound that reacts with the above organic transition metal compound component to form an ionic complex may be used as long as it forms an ionic complex, and particularly, a noncoordinating bulky anion. An ionized ionic compound represented by the general formula (3) having is preferably used.

[C ⁺ ] [A ⁻ ] (3) In the above general formula (3), [C ⁺ ] is a cation, and specifically, the proton itself or trimethylammonium, which contains an active proton, Triethylammonium, tripropylammonium, tributylammonium, N, N-dimethylanilinium, N, N-
Bronsted acids such as those represented by diethylanilinium, triphenylphosphonium, tri (o-tolyl) phosphonium, tri (p-tolyl) phosphonium, tri (mesityl) phosphonium, or carbonium, oxonium, or those containing no active protons. A sulfonium cation, specifically, a compound represented by triphenylcarbenium, tropylium ion, trimethyloxonium, triethyloxonium, triphenyloxonium, or a cation of a metal atom or an organometal. Lithium ion, magnesium ion, palladium ion, platinum ion, copper ion, silver ion, gold ion, mercury ion and etherate compounds in which a base such as ether is coordinated with these, ferrocenium ion, dimethylferro And the like can be mentioned ions, but is not limited thereto.

Further, [A ^-] is an anion is not particularly limited, an anion is used to be weakly coordinated to not react with the organic transition metal compound component described above, for example magnesium with a charge, aluminum Including metals such as or non-metals such as halogen, boron, phosphorus, etc.,
Anions that are bulky and non-nucleophilic are preferred. Specifically ^{_{[AlR 4 -], [BR}} 4 -], [PR 6 -] or [Cl
O ₄ ^-] is an anion represented by the more specific the tetraphenylborate, tetra (pentafluorophenyl) borate, tetra (o-fluorophenyl) borate, tetra (p- fluorophenyl) borate, tetra (m- Fluorophenyl) borate, tetra (2,5-
Difluorophenyl) borate, tetra (1,5-difluorophenyl) borate, tetra (1,6-difluorophenyl) borate, tetra (o-tolyl) borate, tetra (p-tolyl) borate, tetra (2,5-
Dimethylphenyl) borate, tetra (1,5-dimethylphenyl) borate, tetraphenylaluminate,
Tetra (pentafluorophenyl) aluminate, tetra (o-fluorophenyl) aluminate, tetra (p
-Fluorophenyl) aluminate, tetra (m-fluorophenyl) aluminate, tetra (2,5-difluorophenyl) aluminate, tetra (1,5-difluorophenyl) aluminate, tetra (1,6-difluorophenyl) Aluminate, tetra (o-tolyl) aluminate, tetra (p-tolyl) aluminate, tetra (2,5-dimethylphenyl) aluminate, tetra (1,5-dimethylphenyl) aluminate, octadecaborate, dodeca Examples thereof include borate, 1-carbaundecaborate, 1-carbadodecaborate, and the like, but are not limited thereto.

Specific examples of the ionized ionic compound include lithium tetrakispentafluorophenyl borate, anilinium tetrakispentafluorophenyl borate, triphenylcarbenium tetrakispentafluorophenyl borate, tropinium tetrakispentafluorophenyl borate, and lithium tetrakispenta. Examples thereof include, but are not limited to, fluorophenylaluminate, anilinium tetrakispentafluorophenylaluminate, triphenylcarbenium tetrakispentafluorophenylaluminate, and tropinium tetrakispentafluorophenylaluminate.

Further, examples of ionized ionic compounds include those having a bond between aluminum and oxygen. Specific examples include the following general formula (4) or (5).

[0032]

Embedded image

[0033]

[Chemical 4]

The aluminoxane represented by: In the above formula, R ⁴ may be the same or different and is a hydrogen atom, a halogen atom, an alkoxide group or a hydrocarbon group, and specific examples include chlorine, bromine, iodine, methoxy group, ethoxy group, propoxy group, butoxy. Group, phenoxy group, methyl group, ethyl group, propyl group, butyl group,
Hexyl group, phenyl group, tolyl group, cyclohexyl group and the like can be mentioned. q is an integer of 0 to 100.

Methods for producing compounds of this type are known,
(1) Trialkylaluminum is added to a hydrocarbon medium suspension of a compound having adsorbed water and salts containing water of crystallization (magnesium sulfate hydrate, copper sulfate hydrate, aluminum sulfate hydrate, etc.). Examples thereof include a reaction method and (2) a method in which water is allowed to act directly on a trialkylaluminum in a hydrocarbon medium.

The compounds which react with the organic transition metal compound component to form an ionic complex have been exemplified above, but there is no particular limitation as long as it is a compound which turns the organic transition metal compound component into an ionic complex. They can be used, and two or more kinds of components can be used in combination.

If desired, an organometallic component can be used in the above catalyst. Examples of the organometallic compound include metal compounds of Group I, IA, II, IIA, IIB, III or IIIB of the periodic table, which have at least one or more alkyl groups. Preferred are lithium, boron, aluminum, magnesium or zinc compounds, the metal atoms may be the same or different, hydrogen atom, a hydrocarbon group such as an alkyl group, an aryl group and an aralkyl group bonded to the metal by carbon, oxygen. And a compound having a substituent such as an alkoxide or a halogen bonded to the metal, wherein at least one of the substituents is an alkyl group.

Specific examples of the organometallic compound used include alkyllithium such as methyllithium and butyllithium, alkylborane such as triethylborane, alkylaluminum such as trimethylaluminum, triethylaluminum and triisobutylaluminum, and dimethylaluminum fluoride. Alkyl aluminum halides such as dimethyl aluminum chloride, diethyl aluminum chloride, diisobutyl aluminum chloride, diethyl aluminum hydride,
Alkyl aluminum hydride such as diisobutyl aluminum hydride, Alkyl magnesium such as dibutyl magnesium, butyl ethyl magnesium,
Examples thereof include, but are not limited to, Grignard compounds such as methylmagnesium chloride, methylmagnesium bromide, butylmagnesium chloride, and butylmagnesium bromide, and alkylzinc such as diethylzinc and diphenylzinc. These organometallic compounds may be used alone or in combination of two or more depending on the purpose, but when used alone, a compound containing aluminum is preferably used.

The ratio of the organic transition metal compound (a) to the compound (b) which reacts with this compound to form an ionic complex at the time of catalyst preparation is not particularly limited, but is preferably (a). And the molar ratio of (b) is (a) :( b) = 100: 1.
To 1: 1,000,000, and particularly preferably 1: 1 to 1: 100000.

There is no particular limitation on the method for preparing the catalyst from these components (a) and (b), and as an example of the preparation method, each component is mixed in an inert solvent or a monomer to be polymerized is used as a solvent. It can be mentioned. Further, there is no particular limitation on the order of reacting these components. The temperature and time of this reaction are not particularly limited.

The ratio of the organometallic compound (c) at the time of preparing the catalyst is not particularly limited, but the molar ratio of (a) to (c) is preferably (a) :( c) = 100: 0 to 1: 1. 1,000,000
And particularly preferably in the range of 1: 1 to 100,000.

Further, ethylene / α-used in the present invention
The olefin / aromatic vinyl / non-conjugated diene copolymer can be produced in a liquid phase, and the solvent in that case may be any commonly used organic solvent, such as benzene, toluene, Examples include xylene, pentane, hexane, heptane, methylene chloride, etc., or aromatic vinyl compounds, α-olefins themselves can be used as a solvent.

Further, the polymerization temperature in the production of the copolymer of the present invention using the above catalyst system is not particularly limited,
It is preferable to carry out in the range of −100 to 300 ° C., and the polymerization pressure is not particularly limited, but is usually atmospheric pressure to 150 kg.
It is carried out at f / cm ² , and is preferably carried out in the range of atmospheric pressure to 50 kgf / cm ² .

Polymerization can be carried out by any of batch method, semi-continuous method and continuous method, and it can also be carried out in two or more stages by changing the polymerization conditions. Further, the copolymer obtained after the completion of the polymerization is separated and recovered from the polymerization solution by a conventionally known method and dried to obtain a solid copolymer.

Sulfur and / or organic peroxides are used as the crosslinking agent in the ethylene copolymer crosslinked rubber of the present invention, and as the organic peroxide, benzoyl peroxide, t-butylperoxybenzoate, Dicumyl peroxide, t-butyl cumyl peroxide, t-butyl peroxide, 2,5-dimethyl-
2,5-di-t-butylperoxyhexane, 2,5-
Dimethyl-2,5-di-t-butylperoxyhexyne, 2,4-dichlorobenzoyl peroxide, di-
t-butyl peroxydiisopropylbenzene, 1,1
Examples thereof include, but are not limited to, -bis (t-butylperoxy) -3,3,5-trimethylcyclohexane. These organic peroxides may be used alone or in combination of two or more.

The amount of the crosslinking agent added is 0.1-10 parts by weight per 100 parts by weight of the ethylene / α-olefin / aromatic vinyl compound / non-conjugated diene copolymer of the present invention. If it is less than 0.1 part by weight, crosslinking may not be sufficiently carried out, and if it exceeds 10 parts by weight, odor may remain.

If necessary, a crosslinking accelerator is added,
It is also possible to carry out crosslinking.

The crosslinking accelerator used in the present invention includes
Guanidine derivatives such as N, N-diphenylguanidine, N, N-di-o-tolylguanidine and the like; N, N-
Thiourea such as dibutyl thiourea, 2-mercapto imidazoline, tetramethyl thiourea, etc .; xanthogelate salt such as zinc dibutyl xanthate; etc. dithioate salt such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate; hexamethylene Aldehyde ammonia-based compounds such as tetramine, acetaldehyde aniline, butyraldehyde aniline and the like;
Thiazole compounds such as mercaptobenzothiazole and dibenzothiazyl disulfide; thiuram sulfides such as tetramethylthiuram monosulfide, tetraethylthiuram monosulfide, tetramethylthiuram disulfide and tetraethylthiuram disulfide; mercaptobenzothiazole and dibenzothiazyl disulfide , 2-mercaptobenzothiazole zinc, and other thiazole-based compounds; N-cyclohexyl-2-benzothiazole sulfenamide, Nt-
Examples include, but are not limited to, sulfenamides such as butylbenzothiazole sulfenamide and the like. Even if these cross-linking accelerators are single, 2
You may use it in combination of 2 or more types.

When a crosslinking accelerator is used, its amount is 10 parts by weight or less, preferably 5 parts by weight or less, per 100 parts by weight of the copolymer. If the amount exceeds 10 parts by weight, the physical properties of the obtained crosslinked rubber may deteriorate.

It is also possible to use a crosslinking accelerator and a dispersant typified by zinc white, active zinc white, surface-treated zinc white, zinc carbonate, litharge and magnesium oxide during the crosslinking.

Furthermore, the use of a co-crosslinking agent in the present invention is effective because the crosslinking effect is improved.

Examples of the co-crosslinking agent include P.quinone dioxime, P.P dibenzoylquinone dioxime, N-methyl-N'-4-dinitrosoaniline, dinitrosobenzene, lauryl methacrylate and ethylene glycol dimetha. Acrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, diaryl fumarate, diaryl phthalate, tetraaryloxyethane, triaryl cyanurate, aryl methacrylate, Maleimide, phenyl maleimide,
N, N'm-phenylene bismaleimide, maleic anhydride, itaconic acid, divinylbenzene, diarylmelamine, diphenylguanidine, divinyl adipate, vinyltoluene, 1,2-polybutadiene, liquid styrene-
Butadiene copolymer rubber, dipentamethylene thiuram pentasulfide, mercaptobenzthiazole, sulfur and the like may be mentioned, and one or more of these may be used as necessary.

Further, scorch inhibitors represented by phthalic anhydride, benzoic acid, salicylic acid, nitroso compounds, coumarone resins, terpene resins, petroleum hydrocarbon compounds, tackifiers represented by rosin derivatives, and paraffinic softeners. A naphthenic softening agent, an aromatic softening agent, a softening agent represented by asphalt, petrolatum, ozokerite and the like can be added as necessary.

Further, if necessary, calcium carbonate, mica, talc, silica, barium sulfate, calcium sulfate, kaolin, clay, pyroferrite, bentonite, serisanite, zeolite, nepheline sinite,
Inorganic fillers and reinforcing agents such as attapulgite, wollastonite, ferrite, calcium silicate, magnesium carbonate, dolomite, antimony trioxide, zinc oxide, titanium oxide, magnesium oxide, iron oxide, molybdenum disulfide, carbon black, gypsum, quartz Further, organic and inorganic pigments can be blended. Also, release agents, anti-blocking agents, slip agents, antistatic agents, lubricants, heat resistance stabilizers, light stabilizers, UV absorbers, weather resistance stabilizers, foaming agents, defoamers, rust preventives, anti-mold agents. If desired, an ion trap agent, a flame retardant, a flame retardant auxiliary agent, etc. may be added.

Further, the method for producing the crosslinked rubber of the ethylene copolymer of the present invention is not particularly limited, and it can be continuously used in batch type kneaders such as rolls, Banbury mixers, kneaders, screw extruders and rotor type continuous kneaders. Mastication, mixing, blending, etc. are performed using a kneader, and the obtained compound is further extruded, injected, calendered, compressed,
It is shaped and crosslinked by any molding method such as blowing, foaming and transfer molding.

The crosslinking conditions of the ethylene copolymer of the present invention are not particularly limited, but at a temperature of 80 to 280 ° C., 0.5
It is preferably carried out for 40 minutes.

The ethylene-based copolymer crosslinked rubber of the present invention can be used for tires, automobile parts, industrial products, insulators and the like.

[0058]

EXAMPLES The present invention will be described below with reference to examples, but these are illustrative and not restrictive. Various measurements in the examples were carried out by the following methods.

(Ethylene / Propylene / Styrene / 5-
Determination of propylene, styrene and 5-ethylidene-2-norbornene contents in ethylidene-2-norbornene copolymer) 40 using 1,1,2,2-tetrachloroethane as a solvent
It was calculated by measurement of 0 MHz, ¹ H-NMR spectrum (JNMGX400 manufactured by JEOL Ltd.).

(Measurement of molecular weight and molecular weight distribution) o-
Gel permeation chromatography (manufactured by Millipore Corporation) at 140 ° C using dichlorobenzene.
It was calculated in terms of polyethylene by using 150C type GPC).

(Tensile test) According to JIS K6301,
A tensile test was conducted. The temperature was 23 ° C., the dumbbell was No. 3, and the speed was 50 mm / min.

Example 1 Ethylene / Propylene / Styrene / 5-Ethylidene-2
-Synthesis of norbornene copolymer (1) Toluene 2400 ml, styrene 150 ml, 5-ethylidene-2-norbornene 4 in a 5 l autoclave.
5 ml and 250 ml of propylene were added, and the internal temperature was raised to 80 ° C while stirring. At this time, the internal pressure is 4 kg / cm
² is introduced, ethylene is introduced here, the total pressure is 16 kg /
It was raised to cm ² . Next, 10 ml of toluene, 15 mmol of methylaluminoxane, and 15 micromoles of (dimethyl (t-butylamido) (tetramethyl-η5-cyclopentadienyl) silane) dichloride titanium synthesized by a known method were added to another reaction vessel. The mixed solution was stirred for 20 minutes and then introduced into an autoclave to start polymerization. In this polymerization, the total pressure was kept at 16 kg / cm ² by continuously introducing ethylene, and at 40 ° C at 40 ° C.
Minutes.

After completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 100 ° C. for 8 hours. As a result, ethylene: propylene = 68: 32 (molar ratio), styrene content 1.1 mol%, 5-ethylidene-2
42 g of an ethylene / propylene / styrene / 5-ethylidene-2-norbornene copolymer having a norbornene content of 0.6 mol% was obtained. The number average molecular weight of this copolymer is 50.
000 and Mw / Mn = 2.2. Further, the iodine value and the Mooney viscosity (100 ° C.) measured by a known method were 8.8 mg / g and 59, respectively.

Example 2 Ethylene / Propylene / Styrene / 5-Ethylidene-2
-Synthesis of norbornene copolymer (2) Toluene 2100 ml, styrene 450 ml, 5-ethylidene-2-norbornene 6 in a 5 l autoclave.
0 ml and 240 ml of propylene were added, and the internal temperature was raised to 85 ° C while stirring. At this time, the internal pressure is 4 kg / cm
² is introduced, ethylene is introduced here, the total pressure is 16 kg /
It was raised to cm ² . Next, in another reaction vessel, 10 ml of toluene, 21 mmol of methylaluminoxane, (dimethyl (t-butylamido) (tetramethyl-η5-cyclopentadienyl) silane) dichloride titanium 10.5 micromol synthesized by a known method. Was added, and the mixed solution was stirred for 20 minutes and then introduced into an autoclave to start polymerization. In this polymerization, the total pressure was kept at 16 kg / cm ² by continuously introducing ethylene at 85 ° C.
For 25 minutes.

After completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 100 ° C. for 8 hours. As a result, ethylene: propylene = 58: 42 (molar ratio), styrene content 4.5 mol%, 5-ethylidene-2
-48 g of an ethylene / propylene / styrene / 5-ethylidene-2-norbornene copolymer having a norbornene content of 1.6 mol% was obtained. The iodine value measured by a known method is 17.7 mg / g, and the Mooney viscosity (100
C.) was 60.

Example 3 Ethylene / 1-hexene / styrene / 5-ethylidene-
Synthesis of 2-norbornene copolymer 1750 ml of toluene, 375 ml of styrene, and 5-ethylidene-2-norbornene 5 were added to a 5 l autoclave.
0 ml and 1-hexene 375 ml were added, and the internal temperature was raised to 80 ° C. with stirring. At this time, the internal pressure is 1 kg / c
m ² and ethylene was introduced thereinto, and the total pressure was 9 kg /
It was raised to cm ² . Next, 10 ml of toluene, 30 mmol of methylaluminoxane, and 15 μmol of (dimethyl (t-butylamido) (tetramethyl-η5-cyclopentadienyl) silane) dichloride titanium synthesized by a known method were added to another reaction vessel. The mixed solution was stirred for 20 minutes and then introduced into an autoclave to start polymerization. This polymerization was carried out at 80 ° C. for 30 minutes while keeping the total pressure at 9 kg / cm ² by continuously introducing ethylene.

After completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 100 ° C. for 8 hours. As a result, ethylene: 1-hexene = 74: 26 (molar ratio), styrene content 4.6 mol%, 5-ethylidene-2
-48 g of an ethylene / 1-hexene / styrene / 5-ethylidene-2-norbornene copolymer having a norbornene content of 1.4 mol% was obtained. The iodine value measured by a known method is 13.4 mg / g, and the Mooney viscosity (100
C.) was 31.

Example 4 40 g of the copolymer obtained in Example 1, 32 g of HAF carbon black, 20 g of naphthene oil, 0.2 g of stearic acid and 2 g of zinc white were used, and the internal volume was 100 cc and the set temperature was 5
0 ° C., rotation speed 70 rpm. Internal mixer (Labo Plastomill, manufactured by Toyo Seiki Seisakusho) was kneaded for 3 minutes and 30 seconds to obtain a compound.

The surface temperature of the obtained compound is 50 ° C.
The mixture was kneaded by an 8-inch roll kneader set to, and 0.6 g of sulfur, a vulcanization accelerator 2-mercaptobenzothiazole (MBT) 0.2 g, and tetramethylthiuram disulfide (TMTD) 0.6 g were added. The kneading time was 5 minutes. The roll wrapping property at this time was very good.

Crosslink the kneading sheet at 160 ° C. for 20 minutes,
A 1 mm thick pressed piece was obtained and used as a test piece for material testing.

Comparative Example 1 40 g of an ethylene / propylene / 5-ethylidene-2-norbornene copolymer (JSR, EP93), 32 g of HAF carbon black, 20 g of naphthene oil, 0.2 g of stearic acid, and 2 g of zinc white having an internal volume of 100 cc. , Setting temperature 50 ° C., rotation speed 70 rpm. Internal mixer (Labo Plastomill, Toyo Seiki Seisakusho) for 3 minutes 30 minutes
Second kneading was performed to obtain a compound.

The surface temperature of the obtained compound is 50 ° C.
The mixture was kneaded by an 8-inch roll kneader set to, and 0.6 g of sulfur, a vulcanization accelerator 2-mercaptobenzothiazole (MBT) 0.2 g, and tetramethylthiuram disulfide (TMTD) 0.6 g were added. The kneading time was 5 minutes.

Crosslink the kneading sheet at 160 ° C. for 20 minutes,
A 1 mm thick pressed piece was obtained and used as a test piece for material testing.

Example 5 40 g of the copolymer obtained in Example 2, 20 g of HAF carbon black, 0.4 g of stearic acid, 1.2 g of zinc white
Has an internal volume of 100 cc, a set temperature of 50 ° C, and a rotation speed of 50 rp
m. Internal mixer (Labo Plastomill, manufactured by Toyo Seiki Seisakusho) was kneaded for 3 minutes and 30 seconds to obtain a compound.

The surface temperature of the obtained compound is 50 ° C.
The mixture was kneaded by an 8-inch roll kneader set to, and 0.6 g of sulfur and 0.8 g of a vulcanization accelerator N-cyclohexyl-2-benzothiazylsulfenamide (CBS) were added. The kneading time was 5 minutes. The roll wrapping property at this time was very good.

Crosslink the kneading sheet at 160 ° C. for 30 minutes,
A 1 mm thick pressed piece was obtained and used as a test piece for material testing.

Comparative Example 2 40 g of ethylene / propylene / 5-ethylidene-2-norbornene copolymer (JSR, EP24), 20 g of HAF carbon black, 0.4 g of stearic acid, and 1.2 g of zinc white having an internal volume of 100 cc were set. Temperature 50 ° C., rotation speed 50 rpm. Internal mixer (Labo Plastomill, manufactured by Toyo Seiki Seisakusho) was kneaded for 3 minutes and 30 seconds to obtain a compound.

The surface temperature of the obtained compound is 50 ° C.
The mixture was kneaded by an 8-inch roll kneader set to, and 0.6 g of sulfur and 0.8 g of a vulcanization accelerator N-cyclohexyl-2-benzothiazylsulfenamide (CBS) were added. The kneading time was 5 minutes. Kneading sheet at 160 ℃ 3
Cross-linking was performed for 0 minutes to obtain a 1 mm thick pressed piece, which was used as a test piece for material testing.

Example 6 The copolymer obtained in Example 3 was crosslinked in the same manner as in Example 4 to obtain a test piece for material test.

Comparative Example 3 Ethylene / 1-hexene / 5 copolymerized by a known method
-Ethylidene-2-norbornene copolymer (ethylene:
1-hexene = 68: 32 (molar ratio), 5-ethylidene-2-norbornene content 1.4 mol%, Mooney viscosity (100 ° C.) 37) were crosslinked in the same manner as in Comparative Example 1 and used for material testing. The test piece of was obtained.

Table 1 shows the results of the physical property tests of the composition thus obtained.

[0082]

[Table 1]

[0083]

As described above, the ethylene of the present invention /
The α-olefin / aromatic vinyl compound / non-conjugated diene copolymer is a novel ethylene copolymer which is excellent in roll processability and mechanical properties and which can be applied to an ethylene-based crosslinked rubber having a high physical property balance.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C08F 212: 02)

Claims (3)

[Claims] 1. A random copolymer comprising ethylene, an α-olefin, an aromatic vinyl compound and a non-conjugated diene, wherein the molar ratio of ethylene to α-olefin is 30/7.
0 to 90/10, the aromatic vinyl compound content is 0.01 to 30 mol% and the non-conjugated diene content is 0.1 to 30 mol%, and the temperature is 100 ° C.
An ethylene-based copolymer having a Mooney viscosity of 15 to 150. 2. An ethylene-based copolymer composition comprising the ethylene-based copolymer according to claim 1 and sulfur and / or an organic peroxide. 3. An ethylene-based copolymer crosslinked rubber obtained by crosslinking the ethylene-based copolymer according to claim 1 with sulfur and / or organic peroxide.