阅读说明：本技术 直接硫化粘接用橡胶组合物和金属-橡胶复合成形体 (Rubber composition for direct vulcanization bonding and metal-rubber composite molded article ) 是由 酒井贵史 中野贞之 于 2018-05-15 设计创作，主要内容包括：本发明公开了直接硫化粘接用橡胶组合物,其含有：(A)包含乙烯单元和碳原子数为3以上的α-烯烃单元的乙烯-α-烯烃系共聚物橡胶、(B)包含硫原子的硅烷偶联剂和(C)包含硫的硫化剂。硅烷偶联剂的含量相对于乙烯-α-烯烃系共聚物橡胶100质量份为2.7~12质量份。橡胶组合物用于形成直接硫化粘接于金属构件的橡胶成形体。(Disclosed is a rubber composition for direct vulcanization adhesion, which contains (A) an ethylene-alpha-olefin copolymer rubber containing an ethylene unit and an alpha-olefin unit having 3 or more carbon atoms, (B) a silane coupling agent containing a sulfur atom, and (C) a vulcanizing agent containing sulfur, wherein the content of the silane coupling agent is 2.7 ~ 12 parts by mass per 100 parts by mass of the ethylene-alpha-olefin copolymer rubber, and which is used for forming a rubber molded body that is directly vulcanization-adhered to a metal member.)

1. A rubber composition for direct vulcanization bonding, which comprises:

(A) an ethylene-alpha-olefin copolymer rubber containing an ethylene unit and an alpha-olefin unit having 3 or more carbon atoms;

(B) a silane coupling agent containing a sulfur atom; and

(C) a vulcanizing agent comprising sulfur, wherein the vulcanizing agent comprises sulfur,

the content of the silane coupling agent was 2.7 ~ 12 parts by mass per 100 parts by mass of the ethylene- α -olefin copolymer rubber,

the rubber composition for direct vulcanization adhesion is used for forming a rubber molded body which is directly vulcanization-adhered to a metal member.

2. The rubber composition for direct vulcanization adhesion according to claim 1, wherein the silane coupling agent containing a sulfur atom contains a silicon compound represented by the following formula (1):

[ solution 1]

Wherein n represents a numerical value of 1 or more;

Y¹、Y²and Y³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an amino group, an alkoxy group optionally having a substituent, an alkyl group optionally having a substituent, an alkenyl group optionally having a substituent, an alkynyl group optionally having a substituent, an aryl group optionally having a substituent, or an aralkyl group optionally having a substituent;

a represents a linear or branched alkylene group;

z represents a group of formula-A-SiY¹Y²Y³A group represented by the formula, wherein A, Y represents a hydrogen atom, a halogen atom, a formyl group, an acyl group, a carboxyl group, an amino group, a nitro group, an imidazolyl group, a sulfo group, an alkyl group which may be substituted, an alkenyl group which may be substituted, an alkynyl group which may be substituted, an aryl group which may be substituted, or an aralkyl group which may be substituted¹、Y²And Y³The same as above.

3. The rubber composition for direct vulcanization adhesion according to claim 1 or 2, wherein the content of the sulfur is 10 parts by mass or less with respect to 100 parts by mass of the ethylene- α -olefin copolymer rubber.

4. A metal-rubber composite molded article comprising:

a metal member; and

a rubber molded article directly bonded to the metal member and comprising a vulcanizate of the rubber composition according to claim 1 ~ 3.

5. The metal-rubber composite molded body according to claim 4, wherein the metal member is a molded body of iron, aluminum, magnesium, or an alloy containing 1 or more of them.

6. A method for producing a metal-rubber composite molded body, comprising:

forming a rubber molded article directly adhered to a metal member by molding the rubber composition according to claim 1 ~ 3 in a state of being in contact with the metal member, and

vulcanizing the rubber composition.

7. The method for producing a metal-rubber composite molded body according to claim 6, wherein the metal member is a molded body of iron, aluminum, magnesium, or an alloy containing 1 or more of these.

Technical Field

The present invention relates to a rubber composition for direct vulcanization adhesion and a metal-rubber composite molded article.

Background

Ethylene- α -olefin copolymer rubbers represented by ethylene- α -olefin copolymer rubbers and ethylene- α -olefin-nonconjugated polyene copolymer rubbers are excellent in various functions such as weather resistance, heat resistance, and chemical resistance, and are widely used in applications such as automobile parts, electric/electronic parts, and OA equipment parts.

In general, an ethylene- α -olefin copolymer rubber has a low degree of unsaturation and does not have a polar group or a functional group in its molecular structure, and therefore, it itself lacks adhesiveness to a metal. Therefore, in the past, when a rubber molded product is bonded to a metal member, a method of applying an adhesive to the metal member in advance and vulcanizing and molding unvulcanized rubber on the adhesive has been employed in order to improve the bonding strength; a method of vulcanizing and molding unvulcanized rubber containing sulfur on a surface of a metal member plated with brass (glass), thereby vulcanizing the unvulcanized rubber and forming copper sulfide on the surface of the metal member, and bonding the rubber molded body and the metal member with the sulfur (for example, non-patent document 1). As another method for improving the adhesive strength, a method using carbon black treated with silicon as in patent document 1 has also been proposed.

However, the above method requires a complicated step such as surface treatment of metal or application of an adhesive, and thus has room for improvement in terms of production efficiency. The method of applying the adhesive has a problem that it is difficult to uniformly apply the adhesive, and thus the adhesive strength is likely to be uneven. Further, since the adhesive usually contains an organic solvent as a solvent or a dispersant, it is generally more desirable not to use the adhesive from the viewpoint of improving the working environment.

As a method for directly bonding a metal member and a rubber molded body without using an adhesive, a method for directly vulcanization bonding a metal member and a rubber composition containing zinc acrylate as in patent document 2 has been reported.

Disclosure of Invention

Problems to be solved by the invention

By using zinc acrylate, high adhesive strength can be obtained in the case of a rubber composition crosslinked with a peroxide, but zinc acrylate has a problem that it is not necessarily sufficiently effective for improving adhesive strength in a rubber composition crosslinked by vulcanization of sulfur.

Accordingly, an object of one aspect of the present invention is to improve the adhesion strength between a metal member and a rubber molded article when the rubber molded article directly vulcanization-adhered to the metal member is formed using a rubber composition crosslinked by vulcanization of sulfur.

Means for solving the problems

One aspect of the present invention is to provide a rubber composition containing:

(A) an ethylene-alpha-olefin copolymer rubber having an ethylene unit and an alpha-olefin unit having 3 or more carbon atoms;

(B) a silane coupling agent containing a sulfur atom; and

(C) a vulcanizing agent comprising sulfur.

In other words, one aspect of the present invention relates to the use or application of the above-described rubber composition for producing a metal-rubber composite molded article including a metal member and a rubber molded article directly bonded to the metal member and including a vulcanizate of the above-described rubber composition.

The rubber composition according to the present invention is a rubber composition crosslinked by vulcanization of sulfur, and can exhibit high adhesion strength between a metal member and a rubber molded article when the rubber molded article is formed by direct vulcanization adhesion to the metal member.

Another aspect of the present invention provides a metal-rubber composite molded article comprising a metal member and a rubber molded article directly bonded to the metal member and containing a vulcanizate of the rubber composition. The metal-rubber composite molded article can be obtained by a production method comprising the steps of: forming a rubber molded body directly adhered to a metal member by molding the rubber composition in a state of being in contact with the metal member; and vulcanizing the rubber composition. In the metal-rubber composite molded article, the rubber molded article is bonded to the metal member with high adhesion strength.

Effects of the invention

According to one aspect of the present invention, when a rubber molded body directly vulcanization-bonded to a metal member is formed using a rubber composition crosslinked by vulcanization of sulfur, the bonding strength between the metal member and the rubber molded body can be improved.

Drawings

FIG. 1 is a sectional view showing one embodiment of a metal-rubber composite molded article.

Detailed Description

Hereinafter, several embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments.

Rubber composition

One embodiment relates to a rubber composition containing: an ethylene- α -olefin copolymer rubber as component (a), a silane coupling agent containing a sulfur atom as component (B), and a vulcanizing agent containing sulfur as component (C).

Component (A): ethylene-alpha-olefin copolymer rubber

The ethylene- α -olefin copolymer rubber of component (a) according to one embodiment contains an ethylene unit and an α -olefin unit having 3 or more carbon atoms as main monomer units. The number of carbon atoms of the α -olefin unit may be 3 or more and 20 or less. The total content of the ethylene unit and the α -olefin unit in the ethylene- α -olefin copolymer rubber may be 60 mass% or more and 100 mass% or less, or 80 mass% or more and 100 mass% or less, with respect to the total mass of the ethylene- α -olefin copolymer rubber. In the present specification, the term "monomer name + unit" such as "ethylene unit", "α -olefin unit", "nonconjugated polyene unit" means "monomer unit derived from the monomer".

Specific examples of the α -olefin constituting the ethylene- α -olefin copolymer rubber include linear olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene; branched olefins such as 3-methyl-1-butene, 3-methyl-1-pentene and 4-methyl-1-pentene; cyclic olefins such as vinylcyclohexane. These may be constituted alone or in combination of 2 or more to constitute the ethylene- α -olefin copolymer rubber. The α -olefin contained as a monomer unit in the ethylene- α -olefin copolymer rubber may be at least one of propylene and 1-butene, or may be propylene.

The mass ratio of ethylene units/α -olefin units in the ethylene- α -olefin copolymer rubber is not particularly limited, and the sum of both is 100, and may be 90/10 ~ 30/70 or 85/15 ~ 45/55.

The ethylene- α -olefin-based copolymer rubber may be an ethylene- α -olefin-nonconjugated polyene copolymer rubber further containing a nonconjugated polyene unit. The ethylene- α -olefin copolymer rubber may contain the nonconjugated polyene unit in an amount of 0 to 40 in terms of iodine value (unit: g/100g ethylene- α -olefin copolymer rubber). The weather resistance of the rubber molded article can be further improved by reducing the content of the nonconjugated polyene unit to 40 or less in terms of iodine value. From the same viewpoint, the content of the non-conjugated polyene unit may be 0 or more and 35 or less, or 0 or more and 30 or less in terms of iodine value.

The number of carbon atoms of the nonconjugated polyene constituting the ethylene- α -olefin copolymer rubber may be 3 to 20. Specific examples of the non-conjugated polyene include:

chain nonconjugated dienes such as 1, 4-hexadiene, 1, 6-octadiene, 2-methyl-1, 5-hexadiene, 6-methyl-1, 5-heptadiene and 7-methyl-1, 6-octadiene;

cyclic nonconjugated dienes such as cyclohexadiene, dicyclopentadiene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5- (2-propenyl) -2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene, 5- (7-octenyl) -2-norbornene, 5-methylene-2-norbornene and 6-chloromethyl-5-isopropenyl-2-norbornene; and

4-ethylidene-8-methyl-1, 7-nonadiene, 5,9, 13-trimethyl-1, 4,8, 12-tetradecadiene, 4-ethylidene-12-methyl-1, 11-pentadecane diene, 2, 3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2, 2-norbornadiene, 1,3, 7-octatriene, 6, 10-dimethyl-1, 5, 9-undecatriene, 5, 9-dimethyl-1, 4, 8-decatriene, 13-ethyl-9-methyl-1, 9, 12-pentadecatriene, Trienes such as 5,9,8,14, 16-pentamethyl-1, 7, 14-hexadecatriene and 1,4, 9-decatriene.

These may be constituted alone or in combination of 2 or more types to constitute the ethylene- α -olefin copolymer rubber. Among these, the ethylene- α -olefin-based copolymer rubber may contain 5-ethylidene-2-norbornene, dicyclopentadiene, 5-vinylnorbornene, or a combination thereof as a monomer unit.

The total content of the ethylene unit, the α -olefin unit, and the nonconjugated polyene unit in the ethylene- α -olefin copolymer rubber may be 60 mass% or more and 100 mass% or less, or 80 mass% or more and 100 mass% or less, relative to the total mass of the ethylene- α -olefin copolymer rubber.

Specific examples of the ethylene- α -olefin copolymer rubber include ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber, ethylene-propylene-dicyclopentadiene copolymer rubber, ethylene-propylene-1, 4-hexadiene copolymer rubber, ethylene-propylene-1, 6-octadiene copolymer rubber, ethylene-propylene-2-methyl-1, 5-hexadiene copolymer rubber, ethylene-propylene-6-methyl-1, 5-heptadiene copolymer rubber, ethylene-propylene-7-methyl-1, 6-octadiene copolymer rubber, ethylene-propylene-cyclohexadiene copolymer rubber, ethylene-propylene-5-vinyl norbornene copolymer rubber, ethylene-propylene-1, 4-diene copolymer rubber, ethylene-propylene-1, 6-octadiene copolymer rubber, ethylene-propylene-cyclohexadiene copolymer rubber, ethylene-propylene-5-vinyl norbornene copolymer rubber, ethylene-propylene-1, ethylene, Ethylene-propylene-5- (2-propenyl) -2-norbornene copolymer rubber, ethylene-propylene-5- (3-butenyl) -2-norbornene copolymer rubber, ethylene-propylene-5- (4-pentenyl) -2-norbornene copolymer rubber, ethylene-propylene-5- (5-hexenyl) -2-norbornene copolymer rubber, ethylene-propylene-5- (6-heptenyl) -2-norbornene copolymer rubber, ethylene-propylene-5- (7-octenyl) -2-norbornene copolymer rubber, ethylene-propylene-5-methylene-2-norbornene copolymer rubber, ethylene-propylene-5-butene-norbornene copolymer rubber, ethylene, Ethylene-propylene-4-ethylidene-8-methyl-1, 7-nonadiene copolymer rubber, ethylene-propylene-5, 9, 13-trimethyl-1, 4,8, 12-tetradecadiene copolymer rubber, ethylene-propylene-4-ethylidene-12-methyl-1, 11-pentadecadiene copolymer rubber, ethylene-propylene-6-chloromethyl-5-isopropenyl-2-norbornene copolymer rubber, ethylene-propylene-2, 3-diisopropylidene-5-norbornene copolymer rubber, ethylene-propylene-2-ethylidene-3-isopropylidene-5-norbornene copolymer rubber, ethylene-propylene-4-ethylidene-5-norbornene copolymer rubber, ethylene-propylene-2-isopropylidene-2-norbornene copolymer rubber, ethylene-propylene-5-norbornene copolymer rubber, ethylene-propylene-2-isopropylidene-2-isoprene-1, Ethylene-propylene-2-propenyl-2, 2-norbornadiene copolymer rubber, ethylene-propylene-1, 3, 7-octatriene copolymer rubber, ethylene-propylene-6, 10-dimethyl-1, 5, 9-undecatriene copolymer rubber, ethylene-propylene-5, 9-dimethyl-1, 4, 8-decatriene copolymer rubber, ethylene-propylene-13-ethyl-9-methyl-1, 9, 12-pentadecatriene copolymer rubber, ethylene-propylene-5, 9,8,14, 16-pentamethyl-1, 7, 14-hexadecatriene copolymer rubber, and ethylene-propylene-1, 4, 9-decatriene copolymer rubber. These may be used alone or in combination of 2 or more.

The ethylene- α -olefin copolymer rubber in the rubber composition may include an ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber, an ethylene-propylene-dicyclopentadiene copolymer rubber, an ethylene-propylene-5-vinyl norbornene copolymer rubber, or a combination thereof, or may include an ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber.

In the case where the rubber composition contains 2 or more ethylene- α -olefin copolymer rubbers, the mass ratio of ethylene units/α -olefin units and the iodine value are values in the whole of the ethylene- α -olefin copolymer rubber containing the 2 or more ethylene units.

The Mooney viscosity (ML1+4, 100 ℃) of the ethylene-alpha-olefin copolymer rubber at 100 ℃ may be 10 ~ 350 or 30 ~ 300. when the Mooney viscosity is too low, the mechanical strength of the rubber molded article may be reduced, and when the Mooney viscosity is too high, the kneading processability tends to be reduced.

The ethylene- α -olefin copolymer rubber may have a molecular weight distribution (Mw/Mn) of 1.5 or more and 10 or less. When the molecular weight distribution is 1.5 or more, good roll processability of the rubber composition can be easily obtained. When the molecular weight distribution is 10 or less, the mechanical properties of the molded article tend to be improved. From the same viewpoint, the molecular weight distribution of the ethylene- α -olefin copolymer rubber may be 2.0 or more and 7.0 or less. The molecular weight distribution can be adjusted by varying the polymerization conditions.

The molecular weight distribution in the present specification is a ratio (Mw/Mn) calculated from a weight average molecular weight (Mw) and a number average molecular weight (Mn) in terms of standard polystyrene measured by Gel Permeation Chromatography (GPC). The conditions for measuring the weight average molecular weight and the number average molecular weight by the GPC method are shown below, for example.

Seed and seed GPC device: manufactured by Tosoh corporation, trade name HLC-8121GPC/HT

Seed and pillar: manufactured by Tosoh corporation, under the trade name TSKgel GMHHR-H (S) HT

Seed and seed molecular weight standard substance: polystyrene having a molecular weight of 500 or more and 20,000,000 or less

Seeding rate of dissolution solvent: 1.0mL/min

Seed concentration: 1mg/mL

Seed dressing temperature: 140 deg.C

Seeding and leaching solvent: ortho-dichlorobenzene

Seed and injection amount: 500 μ L of

Seed and seed detectors: a differential refractometer.

The content of the ethylene- α -olefin copolymer rubber in the rubber composition may be 20 mass% or more or 35 mass% or more based on the mass of the rubber composition. The content of the ethylene- α -olefin copolymer rubber as the component (a) may be 75 mass% or more or 85 mass% or more, assuming that the total mass of the component (a), the component (B), and the component (C) is 100 mass%.

The method for producing the ethylene- α -olefin copolymer rubber is not particularly limited, and the ethylene- α -olefin copolymer rubber can be produced, for example, by a method including a step of copolymerizing a monomer mixture containing ethylene, an α -olefin, and, if necessary, a non-conjugated polyene in the presence of a catalyst such as a so-called ziegler-natta catalyst or a metallocene catalyst.

As the catalyst for copolymerization, a catalyst formed of a vanadium compound represented by the following formula (1) and an organoaluminum compound represented by the following formula (2) can be used.

VO(OR)_mX_3-m (1)

[ wherein R represents a linear hydrocarbon group having 1 to 8 carbon atoms; x represents a halogen atom; m represents a number satisfying 0< m.ltoreq.3.

R”_jAlX”_3-j (2)

[ wherein R' represents a hydrocarbon group; x' represents a halogen atom; j represents a number satisfying 0< j ≦ 3.

Specific examples of R in formula (1) include methyl, ethyl, n-propyl, n-butyl, n-pentyl and n-hexyl. Among these, R may be a linear alkyl group having 1 to 3 carbon atoms. Examples of X include a fluorine atom and a chlorine atom. m may be a number satisfying 1. ltoreq. m.ltoreq.2.

Specific examples of the vanadium compound represented by the formula (1)VO (OCH)₃)Cl₂、VO(OC₂H₅)Cl₂、VO(O(n-C₃H₇))Cl₂、VO(O(n-C₄H₉))Cl₂、VO(O(n-C₅H₁₁))Cl₂、VO(O(n-C₆H₁₃))Cl₂、VO(O(n-C₇H₁₅))Cl₂、VO(O(n-C₈H₁₇))Cl₂、VO(OCH₃)_0.5Cl_2.5、VO(OC₂H₅)_0.5Cl_2.5、VO(O(n-C₃H₇))_0.5Cl_2.5、VO(O(n-C₄H₉))_0.5Cl_2.5、VO(O(n-C₅H₁₁))_0.5Cl_2.5、VO(O(n-C₆H₁₃))_0.5Cl_2.5、VO(O(n-C₇H₁₅))_0.5Cl_2.5、VO(O(n-C₈H₁₇))_0.5Cl_2.5、VO(OCH₃)_1.5Cl_1.5、VO(OC₂H₅)_1.5Cl_1.5、VO(O(n-C₃H₇))_1.5Cl_1.5、VO(O(n-C₄H₉))_1.5Cl_1.5、VO(O(n-C₅H₁₁))_1.5Cl_1.5、VO(O(n-C₆H₁₃))_1.5Cl_1.5、VO(O(n-C₇H₁₅))_1.5Cl_1.5、VO(O(n-C₈H₁₇))_1.5Cl_1.5、VO(OCH₃)_0.8Cl_2.2、VO(OC₂H₅)_0.8Cl_2.2、VO(O(n-C₃H₇))_0.8Cl_2.2、VO(O(n-C₄H₉))_0.8Cl_2.2、VO(O(n-C₅H₁₁))_0.8Cl_2.2、VO(O(n-C₆H₁₃))_0.8Cl_2.2、VO(O(n-C₇H₁₅))_0.8Cl_2.2And VO (O (n-C)₈H₁₇))_0.8Cl_2.2、VO(OCH₃)_1.8Cl_1.2、VO(OC₂H₅)_1.8Cl_1.2、VO(O(n-C₃H₇))_1.8Cl_1.2、VO(O(n-C₄H₉))_1.8Cl_1.2、VO(O(n-C₅H₁₁))_1.8Cl_1.2、VO(O(n-C₆H₁₃))_1.8Cl_1.2、VO(O(n-C₇H₁₅))_1.8Cl_1.2And VO (O (n-C)₈H₁₇))_1.8Cl_1.2. Of these, the vanadium compound may be VO (OC)₂H₅)Cl₂、VO(OC₂H₅)_0.5Cl_2.5、VO(OC₂H₅)_1.5Cl_1.5、VO(OC₂H₅)_0.8Cl_2.2Or VO (OC)₂H₅)_1.8Cl_1.2. They may be used alone or in combination.

The vanadium compound represented by the formula (1) can be produced by, for example, reacting VOX with₃Reacting with ROH in a specific molar ratio. For example, VOCl₃And C₂H₅The reaction of OH is shown below. Can convert VOX into₃And ROH is supplied to the polymerization vessel, and a vanadium compound of formula (1) is produced in the polymerization vessel.

VOCl₃+m・C₂H₅OH→VO(OC₂H₅)_mCl_3-m+m・HCl

R 'in the formula (2) may be an alkyl group having 1 ~ 10 carbon atoms, specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a pentyl group and a hexyl group, X' may include a fluorine atom, a chlorine atom and the like, and j may be a number satisfying 0< j.ltoreq.2.

Specific examples of the organoaluminum compound represented by the formula (2) include (C)₂H₅)₂AlCl、(n-C₄H₉)₂AlCl、(iso-C₄H₉)₂AlCl、(n-C₆H₁₃)₂AlCl、(C₂H₅)_1.5AlCl_1.5、(n-C₄H₉)_1.5AlCl_1.5、(iso-C₄H₉)_1.5AlCl_1.5、(n-C₆H₁₃)_1.5AlCl_1.5、C₂H₅AlCl₂、(n-C₄H₉)AlCl₂、(iso-C₄H₉)AlCl₂And (n-C)₆H₁₃)AlCl₂. Among these, the organoaluminum compound may be (C)₂H₅)₂AlCl、(C₂H₅)_1.5AlCl_1.5Or C₂H₅AlCl₂. They may be used alone or in combination.

The molar ratio of the amount of the organoaluminum compound of formula (2) to the amount of the vanadium compound of formula (1) (the mole of the organoaluminum compound/the mole of the vanadium compound) may be 0.1 or more and 50 or less, 1 or more and 30 or less, 2 or more and 15 or less, or 3 or more and 10 or less. By adjusting the molar ratio, the viscosity, Mw/Mn, and the like of the ethylene- α -olefin copolymer rubber can be adjusted. For example, when the molar ratio is large, the ethylene- α -olefin copolymer rubber tends to have a high viscosity and Mw/Mn tends to be small.

The polymerization reaction can be carried out, for example, by a method of carrying out polymerization using 1 polymerization vessel or a method of using 2 polymerization vessels connected in series. The monomer, the catalyst, and other components as necessary may be supplied to the polymerization vessel, and the monomer may be polymerized in the polymerization vessel.

The polymerization reaction is usually carried out in a solvent. Examples of the solvent used in the polymerization include aliphatic hydrocarbons such as propane, butane, isobutane, pentane, hexane, heptane and octane; and an inert solvent such as an alicyclic hydrocarbon such as cyclopentane or cyclohexane. They may be used alone or in combination. Among these, the solvent may be an aliphatic hydrocarbon.

The polymerization temperature may be usually 0 ℃ to 200 ℃, 20 ℃ to 150 ℃, or 30 ℃ to 120 ℃. The polymerization pressure may be usually 0.1MPa or more and 10MPa or less, or 0.1MPa or more and 5MPa or less, or 0.1MPa or more and 3MPa or less. The Mw/Mn and the like of the component (A) can be adjusted by adjusting the polymerization temperature. For example, when the polymerization temperature is low, Mw/Mn tends to be small.

The amount of hydrogen supplied to the polymerization vessel may be adjusted to 0.001 ~ 0.1.1 NL, 0.005 ~ 0.05.05 NL, or 0.01 ~ 0.04.04 0.04 NL. per 1kg of the solvent supplied to the polymerization vessel, whereby the Mw/Mn and viscosity of the ethylene- α -olefin copolymer can be adjusted.

The amount of the vanadium compound supplied to the polymerization tank may be 0.002 parts by mass or more and 0.2 parts by mass or less or 0.003 parts by mass or more and 0.1 parts by mass or less per 100 parts by mass of the solvent supplied to the polymerization tank. The viscosity of the ethylene- α -olefin copolymer rubber can be adjusted by adjusting the amount of the vanadium compound relative to the solvent. For example, there is a tendency that the viscosity can be increased by increasing the amount of the vanadium compound.

Component (B): silane coupling agent containing sulfur atom

The silane coupling agent of the component (B) is not particularly limited as long as it contains a sulfur atom and has an organic group bonded to a silicon atom, and typically contains 2 or more sulfur atoms bonded in series. It can be considered that: the reaction of radical species formed by the cleavage of the bonds of sulfur atoms contributes to the improvement of the adhesive strength.

The silane coupling agent containing a sulfur atom may be, for example, 1 or more compounds represented by the following formula (1).

[ solution 1]

In the formula, n represents a value of 1 or more, and n may be 2 ~ 6 on average.

Y¹、Y²And Y³Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an amino group, an alkoxy group which may be substituted, an alkyl group which may be substituted, an alkenyl group which may be substituted, an amino group, an alkoxy group which may be substituted, aAn alkynyl group optionally having a substituent, an aryl group optionally having a substituent or an aralkyl group optionally having a substituent. The silane coupling agent having a silyl group substituted with these groups easily interacts with a metal surface or forms a chemical bond, and can contribute particularly effectively to improvement of the adhesive strength. Y is¹、Y²And Y³At least 1 of them may be a hydrogen atom, a halogen atom, a hydroxyl group, an amino group or an alkoxy group optionally having a substituent. As the alkoxy group, there may be mentioned, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, n-pentoxy, n-hexoxy, n-octoxy, n-dodecoxy, cyclopentoxy, cyclohexoxy, phenoxy and benzyloxy. Examples of the alkyl group include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group, a n-hexyl group, a n-octyl group, a n-dodecyl group, a cyclopentyl group and a cyclohexyl group. Examples of the alkenyl group include a vinyl group, an allyl group, a 1-propenyl group and an isopropenyl group. Examples of the alkynyl group include an ethynyl group and a 2-propynyl group. As the aryl group, for example, phenyl group, methylphenyl group, ethylphenyl group, benzyl group, tolyl group and xylyl group can be cited. Examples of the aralkyl group include a benzyl group. The substituent bonded thereto may be, for example, at least 1 selected from the group consisting of a halogen atom, a hydroxyl group, a formyl group, an acyl group, a carboxyl group, an amino group, a nitro group, a cyano group, an imidazolyl group and a sulfo group.

A represents a linear or branched alkylene group having carbon atoms. Examples of the alkylene group include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, a cyclopropylene group, an n-butylene group, an isobutylene group, a sec-butylene group, a tert-butylene group, a cyclobutyl group, a 1-methyl-cyclopropylene group, a 2-methyl-cyclopropylene group, an n-pentylene group, a 1-methyl-n-butylene group, a 2-methyl-n-butylene group, a 3-methyl-n-butylene group, a 1, 1-dimethyl-n-propylene group, a 1, 2-dimethyl-n-propylene group, a 2, 2-dimethyl-n-propylene group, a 1-ethyl-n-propylene group, a cyclopentylene group, a 1-methyl-cyclobutyl group, a 2-methyl-cyclobutyl group, a 3-methyl-cyclobutyl group, a 1, 2-dimethyl-cyclopropylene group, a, 2, 3-dimethyl-cyclopropylene, 1-ethyl-cyclopropylene, 2-ethyl-cyclopropylene, n-hexylene, 1-methyl-n-pentylene, 2-methyl-n-pentylene, 3-methyl-n-pentylene, 4-methyl-n-pentylene, 1-dimethyl-n-butylene, 1, 2-dimethyl-n-butylene, 1, 3-dimethyl-n-butylene, 2-dimethyl-n-butylene, 2, 3-dimethyl-n-butylene, 3-dimethyl-n-butylene, 1-ethyl-n-butylene, 2-ethyl-n-butylene, 1, 2-trimethyl-n-propylene, 1,2, 2-trimethyl-n-propylene, 1-ethyl-1-methyl-n-propylene, 1-ethyl-2-methyl-n-propylene and cyclohexylene.

Z represents-A-SiY¹Y²Y³A hydrogen atom, a halogen atom, a formyl group, an acyl group, a carboxyl group, an amino group, a nitro group, an imidazolyl group, a sulfo group, an alkyl group optionally having a substituent, an alkenyl group optionally having a substituent, an alkynyl group optionally having a substituent, an aryl group optionally having a substituent or an aralkyl group optionally having a substituent. -A-SiY¹Y²Y³A, Y in¹、Y²And Y³And A, Y in formula (1)¹、Y²And Y³Have the same meaning. Examples of the alkyl group include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group, a n-hexyl group, a n-octyl group, a n-dodecyl group, a cyclopentyl group and a cyclohexyl group. Examples of the alkenyl group include a vinyl group, an allyl group, a 1-propenyl group and an isopropenyl group. As the alkynyl group, for example, ethynyl and 2-propynyl are cited. As the aryl group, for example, phenyl group, methylphenyl group, ethylphenyl group, benzyl group, tolyl group and xylyl group can be cited. Examples of the aralkyl group include a benzyl group. The substituent bonded thereto may be, for example, at least 1 selected from the group consisting of a halogen atom, a hydroxyl group, a formyl group, an acyl group, a carboxyl group, an amino group, a nitro group, an imidazolyl group and a sulfo group.

Specific examples of the compound represented by the formula (1) include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (3-methyldimethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (3-triethoxysilylpropyl) disulfide, bis (3-trimethoxysilylpropyl) disulfide, bis (3-methyldimethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) disulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-trimethoxysilylpropyl) trisulfide, bis (3-methyldimethoxysilylpropyl) trisulfide, bis (2-triethoxysilylethyl) trisulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-trimethoxysilylpropyl) trisulfide, bis (3-methyldimethoxysilylpropyl) trisulfide, bis (, Bis (2-triethoxysilylethyl) trisulfide, bis (3-monoethoxydimethylsilylpropyl) tetrasulfide, bis (3-monoethoxydimethylsilylpropyl) trisulfide, bis (3-monoethoxydimethylsilylpropyl) disulfide, bis (3-monomethoxydimethylsilylpropyl) tetrasulfide, bis (3-monomethoxydimethylsilylpropyl) trisulfide, bis (3-monomethoxydimethylsilylpropyl) disulfide, bis (2-monoethoxydimethylsilylethyl) tetrasulfide, bis (2-monoethoxydimethylsilylethyl) trisulfide and bis (2-monoethoxydimethylsilylethyl) disulfide. These may be used alone or in combination of 2 or more.

As commercially available silane coupling agents containing a sulfur atom, there are Si75 (bis (3-triethoxysilylpropyl) disulfide) manufactured by Evonik Degussa and Si69 (bis (3-triethoxysilylpropyl) tetrasulfide) manufactured by Evonik Degussa.

Typically, the content of the silane coupling agent containing a sulfur atom in the rubber composition is 2.7 ~ 12 parts by mass and may be 3.5 ~ 9.0.0 parts by mass per 100 parts by mass of the ethylene- α -olefin copolymer rubber, and when the content of the silane coupling agent containing a sulfur atom is large, the adhesiveness of the rubber molded article to a metal member tends to be improved, and when the content of the silane coupling agent containing a sulfur atom is too large, the adhesiveness of the rubber molded article to a metal member tends to be reduced.

Component (C): vulcanizing agent containing sulfur

The sulfur used as the vulcanizing agent is not particularly limited, and may be powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur or insoluble sulfur, and the sulfur content in the rubber composition may be 0.01 ~ 10 parts by mass or 0.1 ~ 5 parts by mass per 100 parts by mass of the ethylene- α -olefin copolymer rubber.

(other Components)

The rubber composition of the present embodiment may further contain other components in addition to the components described above within a range not significantly impairing the effects of the present invention. Examples of the other components include reinforcing agents, softening agents, vulcanization accelerators, vulcanization aids, processing aids, and rubber components other than the ethylene- α -olefin copolymer rubber.

Examples of the reinforcing agent include various carbon blacks such as SRF, GPF, FEF, MAF, ISAF, SAF, FT, and MT, calcium carbonate, mica, magnesium silicate, aluminum silicate, lignin, aluminum hydroxide, and magnesium hydroxide. These may be used alone or in combination of 2 or more. The content of the reinforcing agent in the rubber composition may be 200 parts by mass or less or 150 parts by mass or less with respect to 100 parts by mass of the ethylene- α -olefin copolymer rubber.

Examples of the softener include processed oils, lubricating oils, paraffin-based oils such as paraffin and liquid paraffin, naphthene-based oils, petroleum pitches, vaseline, coal tar pitch, castor oil, linseed oil, factice, beeswax, and ricinoleic acid. These may be used alone or in combination of 2 or more. The content of the softener in the rubber composition may be 100 parts by mass or less or 70 parts by mass or less with respect to 100 parts by mass of the ethylene- α -olefin copolymer rubber.

Examples of the vulcanization accelerator include tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, dipentamethylenethiuram monosulfide, dipentamethylenethiuram disulfide, dipentamethylenethiuram tetrasulfide, N '-dimethyl-N, N' -diphenylthiuram disulfide, N '-dioctadecyl-N, N' -diisopropylthiuram disulfide, N-cyclohexyl-2-benzothiazolyl-sulfenamide, N-oxydiethylene-2-benzothiazolyl-sulfenamide, N-diisopropyl-2-benzothiazolyl sulfenamide, 2-mercaptobenzothiazole, 2- (2, 4-dinitrophenyl) mercaptobenzothiazole, and mixtures thereof, 2- (2, 6-diethyl-4-morpholinothio) benzothiazole, dibenzothiazyl disulfide, diphenylguanidine, triphenylguanidine, di-o-tolylguanidine, o-tolylbiguanide, diphenylguanidine-phthalate, n-butyraldehyde aniline, hexamethylenetetramine, acetanilide, 2-mercaptoimidazoline, diphenylthiourea, diethylthiourea, dibutylthiourea, trimethylthiourea, di-o-tolylthiourea, zinc dimethyldithiocarbamate, zinc diethylthiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyl dithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, tellurium diethyldithiocarbamate, zinc dibutylxanthate, and ethylenethiourea, and the like. These may be used alone or in combination of 2 or more. The content of the vulcanization accelerator in the rubber composition may be 0.05 part by mass or more and 20 parts by mass or less or 0.1 part by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the ethylene- α -olefin copolymer rubber.

Examples of the processing aid include fatty acids such as oleic acid, palmitic acid, and stearic acid; fatty acid metal salts such as zinc laurate, zinc stearate, barium stearate, and calcium stearate; a fatty acid ester; glycols such as ethylene glycol and polyethylene glycol. They may be used alone or in combination. The content of the processing aid in the rubber composition may be 0.2 parts by mass or more and 10 parts by mass or less or 0.3 parts by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the ethylene- α -olefin copolymer rubber.

Examples of the rubber component other than the ethylene- α -olefin copolymer rubber include natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, and butyl rubber. The content of the rubber component other than the copolymer rubber in the rubber composition may be 10 parts by mass or more and 40 parts by mass or less or 15 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the ethylene- α -olefin copolymer rubber.

The rubber composition can be obtained by, for example, kneading a mixture containing the ethylene- α -olefin copolymer rubber and other components. Kneading can be carried out using a closed kneading machine such as a stirrer, a kneader, or a twin-screw extruder. The kneading may be carried out until the respective components are uniformly mixed. The kneading time may be 1 minute to 60 minutes. The kneading temperature may be 40 ℃ to 200 ℃. An oil-extended rubber obtained by mixing an ethylene- α -olefin copolymer rubber with a processing oil such as a paraffin oil or a naphthene oil can be used for producing the rubber composition.

Metal-rubber composite molded body

Fig. 1 is a sectional view showing one embodiment of a metal-rubber composite molded body. The metal-rubber molded body 5 shown in fig. 1 includes a metal member 1 and a rubber molded body 3 directly bonded to the metal member 1. The rubber molded body 3 contains the vulcanizate of the rubber composition according to the above embodiment. The rubber molded body 3 is directly bonded to the surface of the metal member 1 without using an adhesive. The rubber molded body 3 can be obtained by a method including the steps of: for example, the rubber composition is molded in a mold in a state of being in contact with the metal member 1 to form the rubber molded body 3 directly adhering to the metal member 1; and vulcanizing the rubber composition. The rubber composition may be vulcanized while the rubber molded product is heated and molded, or the rubber composition with the rubber molded product 3 formed may be vulcanized after the rubber molded product 3 is formed.

The rubber composition is molded in a mold while being heated to 120 ℃ or higher and 250 ℃ or lower, or 140 ℃ or higher and 220 ℃ or lower by a molding machine such as an injection molding machine, a compression molding machine, or a hot air vulcanizing machine, and thereby a rubber molded article vulcanized while being bonded to a metal member can be formed. The molding time is, for example, 1 minute to 60 minutes.

The metal constituting the metal member is not particularly limited, and may be selected from a wide range of metals. The metal member may be, for example, a formed body of magnesium, calcium, barium, titanium, zirconium, iron, cobalt, beryllium, aluminum, chromium, manganese, nickel, copper, zinc, tin, cadmium, silver, platinum, gold, lead, or an alloy containing a combination thereof. The metal member may be a formed body of iron, aluminum, magnesium, or an alloy containing 1 or more of them. The metal member may be a formed body of steel, stainless steel, or aluminum.

The metal-rubber composite molded article can be used for various members such as a rubber roller, an automobile vibration-proof rubber, and a building vibration-proof rubber. The shapes of the metal member and the rubber molded body are not particularly limited, and can be designed according to the application.