JP2016029136A - Rubber composition, crosslinked body, foam and use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition capable of obtaining a molded body having a small molding shrinkage rate and excellent processability and having excellent physical properties such as mechanical strength even when blended at a low blending temperature.SOLUTION: There is provided a rubber composition which comprises an ethylene-α-olefin copolymer (A) satisfying the following requirement (a), an ethylene-α-olefin nonconjugated polyene copolymer rubber (B) satisfying the following requirement (b) (provided that the carbon number of the α-olefin in the copolymer (A) and the copolymer rubber (B) is 3 to 20): (a) the melting point is 110°C or less; (b) the ratio Mw/Mn between the weight average molecular weight Mw and the number average molecular weight Mn determined by GPC analysis is 1.5 to 10.0.SELECTED DRAWING: None

Description

  The present invention relates to a rubber composition, a crosslinked product and a foamed product of the composition, an automobile sealing material comprising the crosslinked product or a foamed product, a door opening trim and a weather strip sponge.

  Ethylene / α-olefin copolymer rubber and ethylene / α-olefin / non-conjugated diene copolymer rubber have no unsaturated bonds in the main chain, so they have better weather resistance and heat resistance than conjugated diene rubbers. Excellent ozone resistance. A rubber composition containing these copolymer rubbers, a crosslinked product of the composition, and a foamed product of the composition are used for the automobile industrial parts, industrial rubber products, electrical insulating materials, civil engineering and building materials, utilizing the above properties. And widely used in rubber products such as rubberized cloth.

  As the rubber composition, for example, rubber compositions containing ethylene / α-olefin / non-conjugated polyene copolymer rubber and polyolefin resin are known (for example, Patent Documents 1 to 3).

JP-A-10-195227 JP 2002-256095 A International Publication No. 2009/072553

From the viewpoint of energy saving and cost reduction in recent years, when the above-mentioned copolymer is kneaded to form a molded body, a molded body having excellent physical properties such as mechanical strength and wear resistance is obtained at a low kneading temperature. In particular, molded articles used for automobile industrial parts are required to have a small shrinkage ratio (molding shrinkage ratio) during molding.
However, when the conventional rubber composition is kneaded at such a low kneading temperature, it may not be possible to obtain a molded article having sufficient physical properties, especially when the kneaded product is extruded. In some cases, it was impossible to obtain a molded article.

  The present invention has been made in view of the above problems, and has a rubber composition that has a small molding shrinkage ratio, excellent workability, and can obtain a molded article having excellent physical properties such as mechanical strength even when kneaded at a low kneading temperature. The purpose is to provide goods.

As a result of intensive studies in order to solve the above problems, the present inventors have found that a rubber composition containing a specific ethylene / α-olefin copolymer and a specific ethylene / α-olefin / non-conjugated polyene copolymer rubber. Thus, the present inventors have found that the above problems can be solved and completed the present invention.
A configuration example of the present invention is as follows.

[1] A rubber containing an ethylene / α-olefin copolymer (A) satisfying the following requirement (a) and an ethylene / α-olefin / non-conjugated polyene copolymer rubber (B) satisfying the following requirement (b): Composition (however, the carbon number of the α-olefin in the copolymer (A) and the copolymer rubber (B) is 3 to 20).
(A) Melting | fusing point is 110 degrees C or less (b) Ratio Mw / Mn of the weight average molecular weight Mw calculated | required by GPC analysis and number average molecular weight Mn is 1.5-10.0.

[2] The rubber composition according to [1], wherein the copolymer (A) satisfies the following requirements (A1) and (A2).
(A1) The density is 0.840 to 0.920 g / cm ³ (A2) The MFR at 190 ° C. and 2.16 kg is 0.1 to 50 g / 10 min.

[3] The rubber composition according to [1] or [2], wherein the copolymer rubber (B) satisfies the following requirements (B1) to (B3).
(B1) The molar ratio of ethylene to an α-olefin having 3 to 20 carbon atoms (ethylene / α-olefin) is 50/50 to 90/10. (B2) The iodine value is 1 to 50 g / 100 g (B3 ) Intrinsic viscosity [η] measured in decalin at 135 ° C. is 0.5 to 7.0 dl / g

  [4] The blend mass ratio [(A) / (B)] of the copolymer (A) and the copolymer rubber (B) is 5/95 to 50/50, [1] to [3] The rubber composition according to any one of the above.

  [5] The rubber composition according to any one of [1] to [4], including a foaming agent (C).

[6] A crosslinked product obtained by crosslinking the rubber composition according to any one of [1] to [5].
[7] A foam obtained by crosslinking and foaming the rubber composition according to any one of [1] to [5].

[8] An automobile sealing material comprising the crosslinked body according to [6] or the foam according to [7].
[9] A door opening trim comprising the crosslinked body according to [6] or the foam according to [7].
[10] A weatherstrip sponge made of the foam according to [7].

  The rubber composition of the present invention can provide a molded article having a small shrinkage ratio, excellent workability, and excellent physical properties such as mechanical strength even when kneaded at a low kneading temperature.

≪Rubber composition≫
The rubber composition according to the present invention comprises an ethylene / α-olefin copolymer (A) satisfying the following requirement (a) and an ethylene / α-olefin / non-conjugated polyene copolymer rubber satisfying the following requirement (b) ( (However, the carbon number of the α-olefin in the copolymer (A) and the copolymer rubber (B) is 3 to 20).
(A) Melting | fusing point is 110 degrees C or less (b) Ratio Mw / Mn of the weight average molecular weight Mw calculated | required by GPC analysis and number average molecular weight Mn is 1.5-10.0.

When a conventional rubber composition is kneaded at a low kneading temperature, two or more kinds of polymers contained in the composition are not compatible, and in particular, an unmelted ethylene / α-olefin copolymer is kneaded. In some cases, this kneaded product was formed, particularly when it was extrusion molded, so that the physical properties of the molded product due to the unmelted polymer sometimes deteriorated.
However, the rubber composition of the present invention has a small molding shrinkage ratio, excellent processability, mechanical strength, abrasion resistance, surface gloss even when kneaded at a low kneading temperature, low compression set at low to high temperatures, etc. It is possible to obtain a molded article having an excellent balance of physical properties. In particular, a molded body having such an effect can be obtained even by extrusion molding.
In the present invention, the “low kneading temperature” is preferably a temperature of 150 ° C. or less, more preferably about 80 to 150 ° C.

Moreover, although the rubber composition of the present invention contains a copolymer having a low melting point and low crystallinity, it is possible to obtain a molded article having a small molding shrinkage ratio and excellent wear resistance. Further, the rubber composition of the present invention includes a low melting point ethylene / α-olefin copolymer. Even if such a copolymer is included, roll processability (winding property to a roll) and compression are also included. A compact with a small permanent set can be obtained.
The reason why the rubber composition of the present invention has these effects is not clear, but it is considered that the copolymer (A) and the copolymer rubber (B) are easily compatible or well dispersed.

The rubber composition of the present invention is such that the copolymer (A) and the copolymer rubber (B) are compatible with each other at the low kneading temperature, preferably about 80 to 150 ° C. It is desirable from the viewpoint of being able to form a molded body having excellent effects.
Whether or not the copolymer (A) and the copolymer rubber (B) are compatible can be observed by, for example, a transmission electron microscope or X-ray scattering measurement.
For this X-ray scattering measurement, a general X-ray scattering measurement apparatus can be used, for example, measurement is performed using a polymer-dedicated beam line BL03XU installed in a large synchrotron radiation facility (such as SPring-8). be able to.

<Ethylene / α-olefin copolymer (A)>
The copolymer (A) is not particularly limited as long as it satisfies the requirement (a).
By using such a copolymer (A) together with the following specific copolymer rubber (B), the molding shrinkage ratio is small, the processability is excellent, and even when kneaded at a low kneading temperature, mechanical strength and abrasion resistance are obtained. A molded product having the above-described effects can be obtained, and an unmelted copolymer (A) does not remain even at a low kneading temperature, and in particular, a molded product having excellent wear resistance can be obtained.

The melting point of the copolymer (A) is preferably 0 to 105 ° C, more preferably 0 to 100 ° C. Since the melting point of the copolymer (A) is in the above range, an unmelted copolymer (A) does not remain even at a low kneading temperature, and in particular, a molded product having a small molding shrinkage ratio and excellent wear resistance. Can be obtained.
Specifically, the melting point can be measured by the method described in the Examples below.

The density of the copolymer (A) is preferably 0.840 to 0.920 g / cm ³ , more preferably 0.850 to 0.915 g / cm ³ , and still more preferably 0.860 to 0. 915 g / cm ³ . When the density is in the above range, a molded article having a small molding shrinkage ratio and excellent in strength characteristics, abrasion resistance and compression set resistance can be obtained.
Specifically, the density can be measured by the method described in the following examples.

The MFR at 190 ° C. and 2.16 kg of the copolymer (A) is preferably 0.1 to 50 g / 10 min, more preferably 0.3 to 20.0 g / 10 min, and still more preferably 0.8. 5 to 5.0 g / 10 min. When the MFR is in the above range, a rubber composition having a small molding shrinkage ratio and excellent workability can be obtained.
Specifically, MFR can be measured by the method described in the Examples below.

The weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) of the copolymer (A) is preferably 10,000 to 500,000, more preferably 20,000 to 300,000. More preferably, it is 20,000-200,000.
The weight average molecular weight (Mn) determined by GPC of the copolymer (A) is preferably 1,000 to 250,000, more preferably 2,000 to 150,000, still more preferably 2, 000-100,000.
The copolymer (A) is preferably a solid at room temperature to about 100 ° C., preferably at a temperature of about 90 ° C.
When the molecular weight is in the above range, a molded article having a low molding shrinkage ratio and excellent wear resistance can be obtained. In addition, since the low molecular weight component is small, the low molecular weight component is less likely to be volatilized or raised in the resulting molded article.
Specifically, Mw and Mn can be measured by the same method as the method for measuring the molecular weight of the copolymer rubber described in the Examples below.

The copolymer (A) is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
The α-olefin is preferably an α-olefin having 3 to 12 carbon atoms, more preferably 3 to 8 carbon atoms from the viewpoint of obtaining a molded article having excellent mechanical strength.
Specific examples of such α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-nonene, Decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene and the like can be mentioned. Of these, propylene, 1-butene, 1-hexene, 1-octene and the like are preferably used. These α-olefins may be used alone or in combination of two or more.

In the copolymer (A), the content of structural units derived from ethylene is preferably 50 to 85 mol%, more preferably 50 to 80 mol% (provided that the structural units derived from ethylene and carbon atoms The total of the structural units derived from the α-olefin of several 3 to 20 is 100 mol%).
When the content of the structural unit derived from ethylene is in the above range, a rubber composition having excellent compatibility with the copolymer rubber (B) can be obtained.

  The method for synthesizing the copolymer (A) is not particularly limited, and ethylene and α-olefin are copolymerized by a conventionally known method using a vanadium catalyst, a Ziegler-Natta catalyst or a metallocene catalyst. Can be manufactured by. From the standpoint of easily obtaining a polymer satisfying the above physical properties, a method of synthesizing using a metallocene catalyst is preferable. Specifically, the metallocene compound and the aluminum-containing compound described in International Publication No. 2008/152935 are preferred. And a synthesis method using a catalyst comprising a metallocene compound and an organoaluminum oxy compound or an ionized ionic compound described in JP-A-9-40586.

In the polymerization of the copolymer (A), in the presence of the catalyst, the polymerization temperature is usually −20 to 200 ° C., preferably 0 to 150 ° C., more preferably 0 to 100 ° C., and the pressure is usually 0. It is preferably performed in the range of more than ˜8 MPa (gauge pressure), preferably more than 0 and ˜5 MPa (gauge pressure). The polymerization time (average residence time when copolymerization is carried out by a continuous method) varies depending on conditions such as catalyst concentration and polymerization temperature, but is usually 0.5 minutes to 5 hours, preferably 10 minutes to 3 hours. .
In the polymerization of the copolymer (A), a molecular weight regulator such as hydrogen may be used.

The amount of each raw material used in the synthesis of the copolymer (A) is not particularly limited, but may be an amount such that the content of structural units derived from ethylene in the obtained copolymer falls within the above range. preferable. Specifically, the α-olefin having 3 to 20 carbon atoms is preferably 25 to 200 parts by mass, more preferably 30 to 150 parts by mass with respect to 100 parts by mass of ethylene.
The amount of the catalyst used is preferably 1.0 × 10 ^{−6 to} 5.0 × 10 ⁻⁶ parts by mass with respect to 1 part by mass of ethylene.

The blending ratio of the copolymer (A) in the rubber composition of the present invention is preferably a blend mass ratio [(A) / (B)] with the copolymer rubber (B), preferably 5/95 to 50/50. More preferably, the amount is 10/90 to 40/60.
When the blending amount of the copolymer (A) is within the above range, a composition in which the copolymer (A) and the copolymer rubber (B) are compatible can be easily obtained, and molding having the above-described effects The body can be easily obtained.
In addition, 1 type may be sufficient as the copolymer (A) contained in the rubber composition of this invention, and 2 or more types may be sufficient as it.

<Ethylene / α-olefin / non-conjugated polyene copolymer rubber (B)>
The copolymer rubber (B) is not particularly limited as long as it satisfies the requirement (b).
The copolymer rubber (B) contained in the rubber composition of the present invention may be one type alone or two or more types.

Mw / Mn of the copolymer rubber (B) is preferably 1.5 to 8.0, more preferably 1.5 to 5.0. When Mw / Mn is in the above range, a molded article having a small molding shrinkage ratio and excellent in mechanical strength and wear resistance can be obtained. In this invention, even if it uses such copolymer rubber (B) with small Mw / Mn, since it uses with the said specific copolymer (A), the rubber composition excellent in workability can be obtained.
Specifically, Mw / Mn can be measured by the method described in the Examples below.

The iodine value of the copolymer rubber (B) is preferably 1 to 50 g / 100 g, more preferably 3.0 to 40.0 g / 100 g, and further preferably 5.0 to 35.0 g / 100 g. It is. When the iodine value is within the above range, a rubber composition having a high effective network chain density is obtained, the molding shrinkage ratio is small, the compression set resistance is excellent, and the environment deterioration resistance (= heat aging resistance) is excellent. A rubber composition capable of providing a molded article is obtained, and is advantageous in terms of cost.
Specifically, the iodine value can be measured by the method (titration method) described in the following examples.

The intrinsic viscosity [η] of the copolymer rubber (B) measured in decalin at 135 ° C. is preferably 0.5 to 7.0 dl / g, more preferably 0.6 to 5.0 dl / g, Preferably it is 0.7-4.0 dl / g. When the intrinsic viscosity [η] is within the above range, a molded article having a small molding shrinkage ratio and excellent strength properties and compression set resistance can be obtained, and a rubber composition excellent in processability can be obtained.
The intrinsic viscosity can be specifically measured by the method described in the following examples.

The Mooney viscosity of the copolymer rubber (B) measured at 100 ° C. is preferably 5.0 to 150.0, more preferably 5.0 to 120.0, and still more preferably 5.0 to 100. .0. When the Mooney viscosity is within the above range, a molding composition having a small molding shrinkage ratio and having a good balance between mechanical strength such as tensile strength, impact resilience and compression set, and a rubber composition having excellent processability are obtained. Is obtained.
The Mooney viscosity can be specifically measured by the method described in the following examples.

The α-olefin in the copolymer rubber (B) is not particularly limited as long as it is an α-olefin having 3 to 20 carbon atoms, and is the same olefin as the α-olefin exemplified in the copolymer (A). The same applies to preferable α-olefins.
These α-olefins may be used alone or in combination of two or more.

  Specific examples of the non-conjugated polyene include 1,4-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4, 5-dimethyl-1,4-hexadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 6-methyl-1,7-octadiene, 7-methyl-1,6-octadiene, etc. A chain non-conjugated diene: methyltetrahydroindene, 5-ethylidene-2-norbornene (ENB), 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 5-vinylidene-2-norbornene, 5-propylidene -5-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, 5-vinyl-2-norbornene (V B), cyclic non-conjugated dienes such as 5-isopropenyl-2-norbornene, 5-isobutenyl-2-norbornene, cyclopentadiene, dicyclopentadiene and norbornadiene; 2,3-diisopropylidene-5-norbornene, 2-ethylidene And triene such as -3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene, 4-ethylidene-8-methyl-1,7-nonadiene and 4-ethylidene-1,7-undecadiene. . Of these, ENB and VNB are particularly preferable. These non-conjugated polyenes may be used alone or in combination of two or more.

  Further, when crosslinking the rubber composition with sulfur, ENB, 1,4-hexadiene and dicyclopentadiene, which are excellent in mechanical strength, are preferable. When the rubber composition is crosslinked with an organic peroxide, crosslinking efficiency and VNB and 5-methylene-2-norbornene, which are excellent in heat aging resistance, are preferred.

  In the copolymer rubber (B), a structural unit derived from ethylene and a structural unit derived from an α-olefin having 3 to 20 carbon atoms (molar ratio of ethylene and α-olefin (ethylene / α-olefin)) is The ratio is preferably 50/50 to 90/10, more preferably 50/50 to 80/20, further preferably 55/45 to 80/20, and particularly preferably 60/40 to 80/20. When this molar ratio is within the above range, a rubber composition can be obtained that is excellent in heat aging resistance, strength characteristics and rubber elasticity, and can provide a molded article excellent in cold resistance and processability.

  The copolymer rubber (B) is a non-conjugated polyene-derived structural unit, usually in an amount of 1.0 to 25.0 wt%, preferably 3.0 to 20 wt%, more preferably 4.0 to 15 wt%. Including.

<Method of polymerizing copolymer rubber (B)>
The polymerization method of the polymer rubber (B) is not particularly limited, but a method of polymerizing using a metallocene catalyst is preferable from the viewpoint that a polymer satisfying the physical properties can be easily obtained. Examples of the metallocene catalyst include a catalyst represented by the following formula (I) and a metallocene catalyst having a structure similar thereto. As the metallocene catalyst having a structure similar to the catalyst represented by the following formula (I), the structure represented by the following formula (iii), preferably the following formulas (iv), (v), (vi), (vii) The catalyst which has is mentioned. Among these, a catalyst represented by the following formula (I) is preferable.

The catalyst represented by the above formula (I) is (t-butylamido) -dimethyl (η ⁵ -2-methyl-s-indasen-1-yl) silanetitanium (II) 1,3-pentadiene (also known as [N -(1,1-dimethylethyl) -1,1-dimethyl-1-[(1,2,3,3A, 8A-η) -1,5,6,7-tetrahydro-2-methyl-S-indacene -1-yl] silaneaminate (2-)-κN] [(1,2,3,4-η) -1,3-pentadiene] -titanium).
In addition, the catalyst represented by the said formula (I) is compoundable by the method as described in international publication 98/49212, for example.

In formula (iii), R ′ represents a hydrogen atom, a hydrocarbyl group, a di (hydrocarbylamino) group or a hydrocarbyleneamino group, which groups have up to 20 carbon atoms.
R ″ represents a hydrocarbyl group having 1 to 20 carbon atoms or a hydrogen atom.
M represents titanium.
Y is, -O -, - S -, - NR * -, - PR * -, - NR 2 * or -PR ₂ ^* (provided that when Y is -NR ₂ ^*, or -PR ₂ ^*, M- Y bond is a coordination bond.
Z ^{* _{is, -SiR * 2 -, - CR}} * 2 -, - SiR * 2 SiR * 2 -, - CR * 2 CR * 2 -, - CR * = CR * -, - CR * 2 SiR * 2 - Or -GeR ^* _2- .

Each R ^* is independently a hydrogen atom or a group containing at least one selected from the group consisting of hydrocarbyl, hydrocarbyloxy, silyl, alkyl halide and aryl halide, R ^* may contain atoms up to atomic number 2 to 20, Z ^* are two R ^* having (when R ^* is not hydrogen) may form a ring, and Z ^* of R ^* R ^{* of} Y may form a ring.

X represents a monovalent anionic ligand group having atoms up to 60 atoms excluding the class of ligands that are cyclic delocalized π-bonded ligand groups.
X ′ represents a neutral linking group having an atom having up to 20 atoms.
X ″ represents a divalent anionic ligand group having an atom having up to 60 atoms.

p represents 0, 1 or 2, q represents 0 or 1, and r represents 0 or 1.
However, when p is 2, q and r are 0, M is an oxidation state of +4, and X is a halide group, hydrocarbyl group, hydrocarbyloxy group, di (hydrocarbyl) amide group, di (hydrocarbyl) Phosphide groups, hydrocarbyl sulfide groups and silyl groups, groups in which these groups are halogen substituted, groups in which these groups are di (hydrocarbyl) amino substituted, groups in which these groups are hydrocarbyloxy substituted, and groups thereof Represents an anionic ligand selected from di (hydrocarbyl) phosphino substituted groups and has up to 30 atoms other than hydrogen atoms.

  However, when r is 1, p and q represent 0, M is an oxidation state of +4, and X ″ is selected from the group consisting of a hydrocarbazyl group, an oxyhydrocarbyl group, and a hydrocarbylene dioxy group. And has atoms other than hydrogen atoms up to 30 atoms.

  However, when p is 1, q and r represent 0, M is an oxidation state of +3, X is allyl, 2- (N, N-dimethylamino) phenyl, 2- (N, N- Represents a stabilizing anionic ligand group selected from the group consisting of (dimethylaminomethyl) phenyl and 2- (N, N-dimethylamino) benzyl.

  Provided that when p and r are 0, q represents 1, M is an oxidation state of +2, and X ′ is a neutral conjugated diene or neutral, optionally substituted with one or more hydrocarbyl groups Wherein X ′ has a carbon atom having up to 40 atoms and forms a π-complex with M.

In the formula (iii), any one of the following (1) to (4) is preferable.
(1) p is 2, q and r are 0, M is an oxidation state of +4, and X independently represents methyl, benzyl or halide.
(2) p and q are 0, r is 1, M is a +4 oxidation state, and X ″ represents a 1,4-butadienyl group that forms a metallocyclopentene ring with M.
(3) p is 1, q and r are 0, M is an oxidation state of +3, and X represents 2- (N, N-dimethylamino) benzyl.
(4) p and r are 0, q represents 1, M is an oxidation state of +2, and X ′ represents 1,4-diphenyl-1,3-butadiene or 1,3-pentadiene.

  In any one of the embodiments (1) to (4), it is more preferable that R ″ represents a hydrogen atom or a methyl group, and particularly preferable that it represents a hydrogen atom.

The formula (iv) is (t-butylamido) dimethyl (η ⁵ -2-methyl-s-indasen-1-yl) silane titanium (II) 2,4-hexadiene.

The formula (v) is (t-butylamido) -dimethyl (η ⁵ -2-methyl-s-indasen-1-yl) silane titanium (IV) dimethyl.

The above formula (vi) is (t-butylamido) -dimethyl (η ⁵ -2,3-dimethylindenyl) silane titanium (II) 1,4-diphenyl-1,3-butadiene.

The formula (vii) is (t-butylamido) -dimethyl (η ⁵ -2,3-dimethyl-s-indasen-1-yl) silanetitanium (IV) dimethyl.

Specifically, the polymerization of the copolymer rubber (B) uses the metallocene catalyst as a main catalyst and a boron compound such as (C ₆ H ₅ ) ₃ CB (C ₆ F ₅ ) ₄ as a cocatalyst. In addition, an organic aluminum compound can be used, and a continuous method or a batch method using a reactor equipped with a stirrer, using an aliphatic hydrocarbon such as hexane as a solvent.

  Examples of the boron compound include trimethylammonium tetrakis (pentafluorophenyl) borate, triethylammonium tetrakis (pentafluorophenyl) borate, tripropylammonium tetrakis (pentafluorophenyl) borate, tri (n-butyl) ammonium tetrakis (pentafluoro). Phenyl) borate, tri (sec-butyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium n-butyltris (pentafluorophenyl) borate N, N-dimethylanilinium benzyltris (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis ( -(T-butyldimethylsilyl) -2,3,5,6-tetrafluorophenyl) borate, N, N-dimethylanilinium tetrakis (4- (triisopropylsilyl) -2,3,5,6-tetrafluoro Phenyl) borate, N, N-dimethylanilinium pentafluorophenoxytris (pentafluorophenyl) borate, N, N-diethylanilinium tetrakis (pentafluorophenyl) borate, N, N-dimethyl-2,4,6-trimethyl Anilinium tetrakis (pentafluorophenyl) borate, trimethylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, triethylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, tripropylammonium tetra Lakis (2,3,4,6-tetrafluorophenyl) borate, tri (n-butyl) ammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, dicyclohexylammonium tetrakis (pentafluorophenyl) borate, N , N-dimethylanilinium tetrakis (2,3,4,6-tetrafluorophenyl) borate, N, N-diethylanilinium tetrakis (2,3,4,6-tetrafluorophenyl) borate and N, N-dimethyl 2,4,6-trimethylanilinium tetrakis (2,3,4,6-tetrafluorophenyl) borate; dialkylammonium salts such as di- (isopropyl) ammonium tetrakis (pentafluorophenyl) borate and dimethyl (t- Butyl) ammo Nium tetrakis (2,3,4,6-tetrafluorophenyl) borate; trisubstituted phosphonium salts such as triphenylphosphonium tetrakis (pentafluorophenyl) borate, tri (o-tolyl) phosphonium tetrakis (pentafluorophenyl) Borate and tri (2,6-dimethylphenyl) phosphonium tetrakis (pentafluorophenyl) borate; disubstituted oxonium salts such as diphenyloxonium tetrakis (pentafluorophenyl) borate, di- (o-tolyl) oxonium tetrakis (Pentafluorophenyl) borate and di (2,6-dimethylphenyl) oxonium tetrakis (pentafluorophenyl) borate; disubstituted sulfonium salts such as diphenylsulfate Tetrakis (pentafluorophenyl) borate, di (o-tolyl) sulfonium tetrakis (pentafluorophenyl) borate and bis (2,6-dimethylphenyl) sulfonium tetrakis (pentafluorophenyl) borate, and the like.

  As the organoaluminum compound, triisobutylaluminum (hereinafter also referred to as “TIBA”) is preferable.

  The polymerization temperature is usually in the range of −20 to 200 ° C., preferably 0 to 150 ° C., more preferably 0 to 120 ° C., and the pressure is usually more than 0 to 8 MPa (gauge pressure), preferably more than 0. Is in the range of ~ 5 MPa (gauge pressure). It is preferable for the reaction temperature and pressure to be in the above-mentioned ranges since the catalyst activity is excellent and the copolymer rubber (B) can be suitably produced.

  The amount ratio of the raw materials used for the polymerization is preferably such that the molar ratio of ethylene to the α-olefin having 3 to 20 carbon atoms falls within the above range. Usually, the α-olefin is 0 per mol of ethylene. .2-1.0 mol, non-conjugated polyene is 0.02-0.10 mol, preferably α-olefin is 0.4-0.8 mol, and non-conjugated polyene is 0.04-0.08 mol.

The polymerization time (average residence time when copolymerization is carried out in a continuous process) varies depending on conditions such as catalyst concentration and polymerization temperature, but is usually 0.5 minutes to 5 hours, preferably 10 minutes to 3 hours. .
Further, a molecular weight regulator such as hydrogen can be used in the copolymerization.

  By using the copolymer rubber (B) obtained by polymerization under the aforementioned polymerization conditions, the rubber composition of the present invention is compatible with the copolymer (A) and the copolymer rubber (B). And the gel-like material is suppressed. Moreover, the molded object formed from this composition is excellent in rigidity, compression set, shape memory property, etc.

<Other ingredients>
In the rubber composition of the present invention, other components other than the copolymer (A) and the copolymer rubber (B) can be blended in a range not impairing the effects of the present invention, depending on the desired purpose. Examples of other components include a foaming agent (C), a vulcanizing agent, a vulcanization accelerator, a vulcanization aid, a plasticizer, a reinforcing agent, an inorganic filler, an anti-aging agent (stabilizer), a processing aid, Various additives, such as an activator, are mentioned.

[Foaming agent (C)]
Specific examples of the foaming agent (C) include inorganic foaming agents such as sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, and ammonium nitrite; N, N′-dimethyl-N, N′-dinitroso Nitroso compounds such as terephthalamide, N, N′-dinitrosopentamethylenetetramine; azo compounds such as azodicarbonamide, azobisisobutyronitrile, azobiscyclohexylnitrile, azodiaminobenzene, barium azodicarboxylate; benzenesulfonyl Sulfonyl hydrazide compounds such as hydrazide, toluenesulfonyl hydrazide, p, p'-oxybis (benzenesulfonyl hydrazide) (OBSH), diphenylsulfone-3,3'-disulfonyl hydrazide; calcium azide, 4,4'-diphenyldisulfoni Azide, etc. azide compounds such p- toluenesulfonyl azide and the like.

  As the foaming agent (C), either a non-supporting type or a supporting type supported on an inorganic powder or the like may be used. However, the water absorption rate at the same specific gravity as compared to the case where the supporting type is used. A non-supporting type foaming agent is preferable because it is low, has excellent sealing performance (soundproofing, waterproofing, vibration proofing) and is excellent in kneading workability.

In the present invention, in order to obtain a light-weight molded product having a specific gravity of 1 or less and to obtain a molded product having good rubber elasticity and hardness, the foaming agent (C) is 100 masses of copolymer rubber (B). Part is preferably 0.001 to 5 parts by weight, more preferably 0.05 to 4 parts by weight, still more preferably 0.05 to 3 parts by weight, still more preferably 0.05 to 1 part by weight, particularly preferably. Is 0.05 to 0.6 parts by mass, most preferably 0.1 to 0.4 parts by mass.
The foaming agent (C) may be a single type or two or more types.

  In order to obtain good product surface skin and uniform foamed cells, the median diameter of the foaming agent (C) is preferably 0.1 to 15 μm, more preferably 0.5 to 10 μm, and further preferably 1 to 5 μm. is there.

[Vulcanizing agent]
As the vulcanizing agent, sulfur, a sulfur compound, an organic peroxide, a phenol resin, an oxime compound, or the like can be used.
One vulcanizing agent may be used alone, or two or more vulcanizing agents may be used.

  As the sulfur compound, sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, selenium dithiocarbamate and the like are preferable. Of the sulfur and sulfur compounds, sulfur and tetramethylthiuram disulfide are more preferred.

  The compounding quantity of sulfur and a sulfur type compound is 0.1-10 mass parts normally with respect to 100 mass parts of copolymer rubber (B), Preferably it is 0.1-7 mass parts, More preferably, it is 0.1-0.1 mass part. 5 parts by mass. When the blending amount of sulfur and the sulfur compound is within the above range, the resulting molded article is excellent in mechanical strength and heat aging resistance.

  As the organic peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5 Examples include -dimethyl-2,5-di (t-butylperoxy) hexyne-3, di-t-butyl peroxide, di-t-butylperoxy-3,3,5-trimethylcyclohexane and t-dibutyl hydroperoxide. . Of these, dicumyl peroxide, di-t-butyl peroxide and di-t-butylperoxy-3,3,5-trimethylcyclohexane are preferred.

  The compounding amount of the organic peroxide is usually 0.001 to 0.05 mol, preferably 0.002 to 0.02 mol, more preferably 0.005 to 0, per 100 g of the copolymer rubber (B). .015 mole. When the amount of the organic peroxide is within the above range, the resulting molded article is excellent in mechanical strength and heat aging resistance.

[Vulcanization accelerator]
When a sulfur compound is used as the vulcanizing agent, it is preferable to use a vulcanization accelerator in combination. Examples of the vulcanization accelerator include N-cyclohexyl-2-benzothiazole sulfenamide, N-oxydiethylene-2-benzothiazole sulfenamide, N, N′-diisopropyl-2-benzothiazole sulfenamide, 2-mercapto Thiazoles such as benzothiazole, 2- (2,4-dinitrophenyl) mercaptobenzothiazole, 2- (2,6-diethyl-4-morpholinothio) benzothiazole and dibenzothiazyl disulfide; diphenylguanidine, triphenylguanidine And guanidines such as diorthotolyl guanidine; acetaldehyde-aniline condensate, butyraldehyde-aniline condensate and aldehyde amine; imidazoline such as 2-mercaptoimidazoline; diethylthiourea and dibuty Thithiourea such as ruthiourea; Thiuram such as tetramethylthiuram monosulfide; Dithioacid salt such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate and tellurium diethyldithiocarbamate; Zanthate such as zinc dibutylxatogenate; (Zinc oxide) and the like. Of these, 2-mercaptobenzothiazole is preferred.
When sulfur is used as the vulcanizing agent, it is preferable to use a vulcanization accelerator in combination, and examples of the vulcanization accelerator include tetramethylthiuram disulfide in addition to the aforementioned vulcanization accelerator. Of these, 2-mercaptobenzothiazole and tetramethylthiuram disulfide are preferred.

The amount of these vulcanization accelerators is usually 0.1 to 20 parts by weight, preferably 0.2 to 15 parts by weight, more preferably 0.5 to 100 parts by weight of the copolymer rubber (B). -10 parts by mass. When the blending amount of the vulcanization accelerator is within the above range, the resulting molded article is excellent in mechanical strength and heat aging resistance.
The vulcanization accelerator may be used alone or in combination of two or more.

[Vulcanization aid]
When an organic peroxide is used as the vulcanizing agent, it is preferable to use a vulcanizing aid in combination. Vulcanization aids include quinone dioximes such as p-quinone dioxime; acrylics such as ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate; allyls such as diallyl phthalate and triallyl isocyanurate; other maleimides; divinyl Examples include benzene.

The amount of the vulcanization aid is usually 0.5 to 2 mol, preferably 0.5 to 1.5 mol, more preferably about equimolar to 1 mol of the organic peroxide used. It is desirable.
The vulcanization aid may be used alone or in combination of two or more.

[Plasticizer]
As the plasticizer (softener), a plasticizer usually used for rubber is used. Specific examples include process oil, lubricating oil, paraffin oil, liquid paraffin, petroleum asphalt, petroleum jelly, coal tar, castor oil, linseed oil, sub, beeswax, atactic polypropylene, and coumaroindene resin. Among these, process oil and paraffin oil are particularly preferably used.

In order to obtain good kneadability, the plasticizer is usually used at a ratio of 20 parts by mass or more with respect to 100 parts by mass of the copolymer rubber (B). When using process oil as a plasticizer, the compounding quantity is preferably 20 to 150 parts by mass, more preferably 30 to 120 parts by mass with respect to 100 parts by mass of the copolymer rubber (B).
The plasticizer may be a single type or two or more types.

[Reinforcing agent and inorganic filler]
In the rubber composition of the present invention, a reinforcing agent and an inorganic filler are blended in order to improve mechanical properties such as tensile strength, tear strength, and abrasion resistance of the obtained molded body and to further reduce molding shrinkage. It is preferable to do.
Specifically, Asahi # 55G, Asahi # 60G (above, manufactured by Asahi Carbon Co., Ltd.), Seast (SRF, GPF, FEF, MAF, HAF, ISAF, SAF, FT, MT, etc.) carbon black (Tokai Carbon) (Manufactured by Co., Ltd.), those obtained by surface-treating these carbon blacks with a silane coupling agent or the like, silica, activated calcium carbonate, fine powder talc, fine powder silicic acid or the like can be used.
As the inorganic filler, light calcium carbonate, heavy calcium carbonate, talc, clay, or the like can be used. Of these, Asahi # 55G, Asahi # 60G, and “Seast HAF” carbon black are preferred.

The compounding amount of the reinforcing agent and / or the inorganic filler is usually 1 to 500 parts by mass, preferably 1 to 400 parts by mass, and more preferably 1 to 300 parts by mass with respect to 100 parts by mass of the copolymer rubber (B). is there. When the blending amount of the reinforcing agent and / or the inorganic filler is within the above range, the obtained molded body is excellent in mechanical strength, which is preferable.
The reinforcing agent and / or inorganic filler may be used alone or in combination of two or more.

[Anti-aging agent (stabilizer)]
By blending an anti-aging agent with the rubber composition of the present invention, it is possible to extend the life of the resulting molded article. As such an anti-aging agent, conventionally known anti-aging agents such as amine-based anti-aging agents, phenol-based anti-aging agents, sulfur-based anti-aging agents and the like can be used.

  Specific examples of the anti-aging agent include aromatic secondary amine-based anti-aging agents such as phenylbutylamine, N, N-di-2-naphthyl-p-phenylenediamine, dibutylhydroxytoluene, tetrakis [methylene (3, 5-di-tert-butyl-4-hydroxy) hydrocinnamate] phenolic antioxidants such as methane; bis [2-methyl-4- (3-n-alkylthiopropionyloxy) -5-tert-butylphenyl] Thioether-based antioxidants such as sulfide; dithiocarbamate-based antioxidants such as nickel dibutyldithiocarbamate; 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, dilaurylthiodipropionate, distearylthiodipropio And sulfur-based anti-aging agents such as nates.

  These anti-aging agents can be used alone or in combination of two or more, and the amount of the anti-aging agent is usually 0.01 to 10 parts per 100 parts by mass of the copolymer rubber (B). Part by mass, preferably 0.01 to 7 parts by mass, and more preferably 0.01 to 5 parts by mass. When the blending amount of the anti-aging agent is within the above range, the molded article obtained is excellent in heat aging resistance, which is preferable.

[Processing aid]
As processing aids, those generally blended into rubber as processing aids can be widely used. Specific examples include ricinoleic acid, stearic acid, palmitic acid, lauric acid, barium stearate, zinc stearate, calcium stearate, zinc laurate or esters. Of these, stearic acid is preferred.

The processing aid can be appropriately blended in an amount of usually 30 parts by mass or less, preferably 25 parts by mass or less, more preferably 20 parts by mass or less with respect to 100 parts by mass of the copolymer rubber (B). A blending amount of the processing aid within the above range is preferable because excellent processability such as kneading processability, extrusion processability, and injection moldability is achieved.
One type of processing aid may be used alone, or two or more types may be used.

[Activator]
Examples of the activator include glycols such as polyethylene glycol and diethylene glycol; amines such as di-n-butylamine and triethanolamine.
The compounding quantity of an activator is 0.2-10 mass parts with respect to 100 mass parts of copolymer rubber (B), Preferably it is 0.3-5 mass parts, More preferably, it is 0.5-4 mass parts. is there.
The activator may be one kind alone or two or more kinds.

<Method for preparing rubber composition>
The rubber composition of the present invention is not particularly limited as long as it contains the copolymer (A) and the copolymer rubber (B), but the copolymer (A) and the copolymer rubber (B) It can be prepared by kneading together with other components as necessary using a Banbury mixer, an internal mixer, a kneader, an open roll or the like that is usually used as a rubber kneader. The kneading temperature in this case is not particularly limited, but is preferably 80 to 250 ° C., more preferably 80 to 200 ° C., and the kneading time is preferably 1 to 20 minutes, more preferably 1 to 10 minutes. The mixing specific energy is preferably 0.001 to 10 kw · h / kg.
The rubber composition of the present invention is such that the copolymer (A) and the copolymer rubber (B) are easily compatible even at a low kneading temperature, and a rubber capable of forming a molded product having the above-described effect even at such a low kneading temperature. Since the composition can be obtained, from the viewpoint of energy saving and cost reduction, the kneading temperature is preferably 150 ° C. or less, more preferably about 80 to 150 ° C., and still more preferably about 90-140 ° C.

  In addition, the rubber composition of the present invention is prepared by adding the copolymer (A) to a mixture of the copolymer rubber (B) and an organic solvent, kneading and desolvating in advance. After preparing a kneaded product in which (A) is uniformly dispersed in the copolymer rubber (B), it may be prepared by a method in which the other components are blended and kneaded if necessary.

The organic solvent that can be used in this case is not particularly limited, and examples thereof include conventionally known hydrocarbon solvents that can be used when preparing the copolymer rubber (B). Specific examples of such hydrocarbon solvents include aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, and kerosene and their halogen derivatives, and alicyclic rings such as cyclohexane, methylcyclopentane, and methylcyclohexane. Aromatic hydrocarbons and their halogen derivatives, aromatic hydrocarbons such as benzene, toluene and xylene and their halogen derivatives. These organic solvents may be used alone or in combination of two or more.
Moreover, the usage-amount of an organic solvent becomes like this. Preferably it is 3-10 mass parts with respect to 100 mass parts of copolymer rubber (B).

  Moreover, the rubber composition of the present invention is prepared by kneading at least the copolymer (A) and the copolymer rubber (B) as described above, and then using rolls such as an open roll. , A foaming agent (C), a vulcanizing agent, a vulcanization accelerator, if necessary, a defoaming agent, a foaming aid, a vulcanizing aid, and the like are additionally mixed, and the roll temperature is preferably 40 to 80 ° C. The rubber composition for extrusion obtained by kneading after preferably kneading for 5 to 30 minutes may be used.

≪Molded body≫
The molded article of the present invention is obtained using the rubber composition of the present invention. Specifically, a crosslinked product obtained by crosslinking the rubber composition of the present invention and the rubber composition of the present invention are crosslinked and foamed. The foam obtained is obtained.
Such a molded body can be obtained by molding the rubber composition of the present invention by a transfer molding method, an injection molding method, a mold molding method, or a press molding method. Specifically, the rubber composition obtained by the above method is extruded into a product shape with a rubber extruder, and then introduced into a vulcanization tank, hot air, fluidized bed, molten salt tank (LCM), PCM. By heating by means such as (Powder Curing Medium or Powder Curing Method) or microwave, it can be prepared by vulcanization and foaming. Preferably, it can be obtained by continuous vulcanization and foaming by hot air vulcanization tank (HAV), LCM, PCM, or continuous extrusion using HAV and decimeter wave (UHF).

Since the molded article of the present invention is obtained using the rubber composition of the present invention, the molding shrinkage ratio (with respect to mold dimensional shrinkage) when the rubber composition of the present invention is crosslinked to obtain a molded article is small. This molding shrinkage ratio varies depending on the rubber composition used and the crosslinking conditions, but is preferably 2% or less.
When the molding shrinkage rate is in the above range, when forming a molded body, it is easy to maintain the shape of the mold, and a molded body having high dimensional accuracy can be obtained. It can be suitably used for applications requiring high dimensional accuracy.
Specifically, the molding shrinkage can be measured by the method described in the following examples.

  As the crosslinking conditions, the crosslinking temperature is usually 140 to 300 ° C, preferably 150 to 270 ° C, more preferably 150 to 250 ° C, and the crosslinking time is usually 0.5 to 30 minutes, preferably 0.5. -20 minutes, more preferably 0.5-15 minutes.

Moreover, the said molded object can also be obtained by the method of preforming the rubber composition of this invention by the said shaping | molding method etc. and irradiating an electron beam.
In this case, an electron beam having an energy of 0.1 to 10 MeV may be irradiated so that the absorbed dose is usually 0.5 to 35 Mrad, preferably 0.5 to 20 Mrad, more preferably 1 to 10 Mrad.

<Application>
The molded body is suitably used in fields where weather resistance, heat aging resistance, wear resistance, low temperature flexibility and the like are required. Specifically, automotive parts, marine parts, civil engineering and building parts, medical parts, parts for electrical and electronic equipment, transportation equipment and leisure parts, hoses (radiator hoses, heater hoses, etc.), anti-vibration rubber, It is suitably used for sheets, various belts, various packings, sealing materials, potting materials, coating materials and adhesives.

Automotive parts include, for example, glass run channels, weatherstrip sponges, door opening trims, sealing members, grommets, automobile engine gaskets, electrical parts or oil filter sealing materials; igniter HID or automotive hybrid IC potting materials; Examples include coating materials for bodies, window glass for automobiles, engine control boards; gaskets such as oil pans or timing belt covers, moldings, headlamp lenses, sunroof seals, and adhesives for mirrors. Examples of weather strip sponges include door weather strips, trunk weather strips, luggage weather strips, roof side rail weather strips, sliding door weather strips, ventilator weather strips, sliding roof weather strips, front window weather strips, rear window weather strips, Examples include quarter window weather strips, lock pillar weather strips, door glass outer weather strips, and door glass inner weather strips.
These automotive parts are often formed by extrusion molding. In this case, the kneadability of the rubber composition and the compatibility of the components contained in the rubber composition are particularly important in the properties of the obtained molded body. A big influence. Since the rubber composition of the present invention is excellent in kneadability and compatibility of components contained in the composition, a molded body having excellent physical properties can be obtained even when the molded body is formed by extrusion molding.

  Examples of marine components include wiring connection branch boxes, electrical system components or electric wire sealing materials; electric wires or glass adhesives.

  Civil engineering building parts include, for example, joint joints for glass screens in commercial buildings, joints around glass with sashes, interior joints in toilets, washrooms or showcases, joints around bathtubs, and for prefabricated houses Sealant for building materials used for joints for outer wall expansion joints and sizing boards; Sealant for double-glazed glass; Sealant for civil engineering used for road repairs; Paints and adhesives for metal, glass, stone, slate, concrete or tile An adhesive sheet, a waterproof sheet, or a vibration-proof sheet.

  Examples of the medical parts include a medical rubber plug, a syringe gasket, and a decompression blood vessel rubber plug.

  Examples of parts for electrical / electronic equipment include heavy electrical parts, weak electrical parts, electrical / electronic equipment circuits and circuit board sealing materials, potting materials, coating materials or adhesives; electric wire covering repair materials; electric wire joint parts insulation Examples include sealing materials; rolls for OA equipment; vibration absorbers; grommets; or gel or capacitor encapsulants.

  Examples of the parts for transport aircraft include parts such as automobiles, ships, airplanes, and railway vehicles.

  Examples of leisure parts include swimming members such as swimming caps, diving masks, earplugs, and gel cushioning members such as sports shoes and baseball gloves.

  Anti-vibration rubber includes, for example, automotive anti-vibration rubber (engine mount, liquid seal engine mount, damper pulley, chain damper, carburetor mount, torsional damper, strut mount, rubber bush, bumper rubber, helper rubber, spring seat, Shock absorber, air spring, body mount, bumper guard, muffler support, rubber coupling, center bearing support, clutch rubber, differential mount, suspension bush, sliding bush, cushion strut bar, stopper, handle damper, radiator supporter or muffler hanger) Anti-vibration rubber for railways (slab mat, ballast mat or track mat), anti-vibration rubber for industrial machinery (expansion joint, flexi Le joint, bush, mounted) and the like.

  Examples of the sheet include a roofing sheet and a water stop sheet.

  Various belts include power transmission belts (V belts, flat belts, toothed belts, timing belts), transport belts (light transport belts, cylindrical belts, rough top belts, transport belts with flanges, transport with U-shaped guides) Belt, V-type guided conveyor belt) and the like.

  Suitable examples of the sealing material include a refrigerator, a freezer, a washing machine, a gas meter, a microwave oven, a steam iron, and an earth leakage breaker. The sealing material refers to a material to be sealed (sealed or sealed). Further, in various industries such as machinery, electricity, chemistry, etc., a material used for the purpose of watertightness and airtightness of the joint portion and the contact portion is also a sealing material in a broad sense.

  Examples of the potting material include a material for potting a transformer high-voltage circuit, a printed circuit board, a high-voltage transformer with a variable resistance portion, an electrical insulation component, a semiconductive component, a conductive component, a solar cell, or a television flyback transformer.

  Examples of coating materials include various circuit elements such as high voltage thick film resistors or hybrid ICs; electrical insulation components; semiconductive components; conductive components; modules; printed circuits; ceramic substrates; diodes, transistors, bonding wires, etc. Examples thereof include a material for coating a buffer material; a semiconductive element; or an optical fiber for optical communication.

  As the adhesive, for example, a cathode ray tube wedge, a neck, an electrically insulating component, a semiconductive component, or an adhesive of a conductive component is preferably exemplified.

  In addition to the above, the molded body includes a cup and seal material for automobiles (master cylinder piston cup, wheel cylinder piston cup, constant velocity joint boot, pin boot, dust cover, piston seal, packing, O-ring, diaphragm, dam window shield, Door mirror bracket, seal head lamp, seal cowl top), industrial sealing material (capacitor packing, O-ring, packing), foam (hose protection sponge, cushion sponge, heat insulation sponge, insulation pipe), covered electric wire, Electric wire joints, electrical insulation parts, semiconductive rubber parts, OA equipment rolls (charging rolls, transfer rolls, developing rolls, paper feed rolls), industrial rolls (iron rolls, paper rolls, printing electric rolls), anode caps ,plug Cap, ignition cable, lamp socket cover, terminal cover, wiper blade, various tubes (vacuum tube, tire tube), air spring, shoe sole, shoe heel, tire sidewall, is suitably used in applications such as fabric coatings.

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

Examples of the ethylene / α-olefin copolymer (A) used in the following examples and comparative examples are EBR-1 to EBR-3 and ethylene / 1-octene copolymers, which are ethylene / 1-butene copolymers. EOR-1 was used.
EBR-1 to EBR-3 were synthesized based on the method described in Example 1 of International Publication No. 2008/152935, and EOR-1 was synthesized based on the method described in Example 5 of International Publication did.

Moreover, the following linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) were used as a polymer for comparative examples.
・ LLDPE: "ULTZEX 2022L" manufactured by Prime Polymer Co., Ltd.
LDPE: “DND-2450” manufactured by NUC Corporation

  The methods for measuring the density, MFR and melting point of these polymers are shown below. The results are shown in Table 1.

〔density〕
Density was measured according to ASTM D1505.

[MFR]
MFR was measured at 190 ° C. and 2.16 kg load according to ASTM D 1238-65T.

[Melting point]
Using a differential scanning calorimeter RDC220 (manufactured by Seiko Instruments), about 10 mg of a sample was packed in an aluminum pan for measurement, heated to 200 ° C. at 50 ° C./min, held at 200 ° C. for 10 minutes, then 10 ° C. / The melting point was determined from the endothermic curve when the temperature was lowered to −100 ° C. in minutes and then raised to 200 ° C. at 10 ° C./min.

<Copolymer rubber>
The ethylene / α-olefin / non-conjugated polyene copolymer rubber (B) used in the following Examples and Comparative Examples was synthesized as follows. Table 2 shows the physical properties of the obtained copolymer rubber.

[Method of synthesizing ethylene / propylene / 5-ethylidene-2-norbornene random copolymer rubber (EPT-1)]
The polymerization reaction of ethylene, propylene and 5-ethylidene-2-norbornene (ENB) was continuously performed at 110 ° C. using a 300 L polymerization vessel equipped with a stirring blade.
Specifically, hexane (feed amount 41 kg / h) is used as a polymerization solvent, ethylene feed amount is 4.8 kg / h, propylene feed amount is 5.0 kg / h, and ENB feed amount is 0.65 kg / h. Continuously fed to the vessel. (T-Butylamido) -dimethyl (η ⁵ -2-methyl-s-indacene-1-yl) silane titanium which is a catalyst represented by the formula (I) as a main catalyst while maintaining the polymerization pressure at 1.5 MPa (II) 1,3-pentadiene was continuously supplied to the polymerization vessel so as to be 0.046 mmol / h. Further, (C ₆ H ₅ ) ₃ CB (C ₆ F ₅ ) ₄ was 0.23 mmol / h as a cocatalyst and triisobutylaluminum (TIBA) was 10.0 mmol / h as an organoaluminum compound, respectively. The polymerizer was continuously fed.

[Method of synthesizing ethylene / propylene / 5-ethylidene-2-norbornene random copolymer rubber (EPT-2, 3 and 5)]
Except for changing the feed amounts of ethylene, propylene and ENB, “EPT-2”, “EPT-” are ethylene / propylene / 5-ethylidene-2-norbornene random copolymer rubbers under the same conditions as in Example 1. 3 "and" EPT-5 "were synthesized.

[Ethylene / propylene / 5-ethylidene-2-norbornene random copolymer rubber (EPT-4)]
“Esprene 505A” manufactured by Sumitomo Chemical Co., Ltd. was used as the ethylene / propylene / 5-ethylidene-2-norbornene random copolymer rubber (EPT-4).

[Composition of copolymer rubber]
Using an ECX400P type nuclear magnetic resonance apparatus manufactured by JEOL Ltd., measurement temperature: 120 ° C., measurement solvent: ODCB-d ₄ (orthodichlorobenzene-d ₄ ), integration number: 512 times, ¹ HNMR The composition of the copolymer rubber was confirmed by measuring the spectrum.
In Table 2 below, the amount of units derived from ethylene in the copolymer rubber is defined as the ethylene content, and the amount of units derived from 5-ethylidene-2-norbornene in the copolymer rubber is defined as the ENB content. In addition, the value of the ethylene content in the following Table 2 indicates the mole of ethylene-derived units in a total of 100 moles of the amount of units derived from ethylene and the amount of units derived from α-olefin.

[Mooney viscosity of copolymer rubber [ML (1 + 4) 100 ° C.]]
The Mooney viscosity [ML (1 + 4) 100 ° C.] of the copolymer rubber was measured using a Mooney viscometer (SMV202 type manufactured by Shimadzu Corporation) under the condition of 100 ° C. in accordance with JIS K6300.

[Molecular weight distribution of copolymer rubber (Mw / Mn)]
The molecular weight distribution of the copolymer rubber was represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by GPC. For GPC, GMH-HT and GMH-HTL manufactured by Tosoh Corporation were used for the column, and orthodichlorobenzene was used for the solvent.

[Intrinsic viscosity of copolymer rubber [η]]
The intrinsic viscosity [η] of the copolymer rubber was measured at a temperature of 135 ° C. using a fully automatic intrinsic viscometer manufactured by Kouai Co., Ltd., using decalin as a measurement solvent.

[Iodine value of copolymer rubber]
The iodine value of the copolymer rubber was measured according to JIS K0070.

[Example 1]
MIXTRON BB MIXER (manufactured by Kobe Steel, Ltd., BB-4 type, volume 2.95 L, rotor 4WH), 100 parts by mass of copolymer rubber (EPT-1), copolymer (EBR-1) 15 parts by mass, 3 parts by mass of activated zinc white (trade name; Meta Z-102, manufactured by Inoue Lime Industry Co., Ltd.) as a vulcanization accelerator, 1 part by mass of stearic acid as a processing aid, and “Asahi #” as a reinforcing agent 60 parts "(trade name; manufactured by Asahi Carbon Co., Ltd.) and 45 parts by weight" Diana Process Oil PW-380 "(trade name; manufactured by Idemitsu Kosan Co., Ltd.) as a softening agent were kneaded. The kneading conditions were a rotor rotation speed of 50 rpm and a floating weight pressure of 3 kg / cm ² . After all the materials were added and the material temperature reached 100 ° C., which is equal to or higher than the melting point of EBR-1, a rubber compound was obtained by kneading for 2 minutes.

  Next, after confirming that the obtained rubber compound had a temperature of 40 ° C., “Noxeller MDB” (trade name; Ouchi Shinsei Chemical Co., Ltd.) as a vulcanization accelerator was added to the rubber compound using an 8-inch roll. (Manufactured by Co., Ltd.) 0.5 parts by mass, 1.0 parts by mass of “Sunseller BZ” (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.) as a vulcanization accelerator, and “Sunseller TBT” as a vulcanization accelerator 0.5 parts by mass (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.) and 1.0 mass by mass of “Sunseller 22-C” (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.) as a vulcanization accelerator. 1.0 parts by mass of sulfur as a vulcanizing agent was added and kneaded. The kneading conditions were as follows: rubber temperature kneading by setting the roll temperature to the front roll / rear roll = 80 ° C./80° C., the roll rotation speed to the front roll / rear roll = 16 rpm / 18 rpm, and the roll gap to 2 mm for 8 minutes. I got a thing.

  The obtained rubber kneaded product was heated and crosslinked for 5 minutes with a press set at 180 ° C. to prepare a vulcanized molded body (rubber sheet).

[Examples 2 to 4]
In Example 1, a rubber kneaded material and a vulcanized molded body were obtained in the same manner as in Example 1 except that the polymers described in Table 3 below were used instead of EPT-1 and EBR-1.

[Comparative Examples 1 and 2]
In Example 1, instead of EPT-1 and EBR-1, the polymers shown in Table 3 below were used, and the kneading temperature (temperature at which a rubber compound was obtained) in MIXTRON BBMIXER was adjusted to a material temperature of 150 ° C. A rubber kneaded product and a vulcanized molded body were obtained in the same manner as in Example 1 except that the time was changed to 2 minutes after arrival.

[Comparative Example 3]
In Example 1, instead of EPT-1 and EBR-1, the polymers described in Table 3 below were used, and the kneading temperature (temperature at which a rubber compound was obtained) in MIXTRON BBMIXER was adjusted to 130 ° C. A rubber kneaded product and a vulcanized molded body were obtained in the same manner as in Example 1 except that the time was changed to 2 minutes after arrival.

[Examples 5 and 6]
In Example 1, instead of EPT-1 and EBR-1, the polymers listed in Table 4 below were used, and the amounts of “Asahi # 60G” (carbon black) and “Diana Process Oil PW-380” used were A rubber kneaded product and a vulcanized molded body were obtained in the same manner as in Example 1 except that the amounts were changed to 150 parts by mass and 60 parts by mass, respectively.

[Comparative Example 4]
In Example 1, in place of EPT-1 and EBR-1, the polymers described in Table 4 below were used, and the amounts of “Asahi # 60G” and “Diana Process Oil PW-380” used were 170 parts by mass, respectively. A rubber kneaded product and a vulcanized molded body were obtained in the same manner as in Example 1 except that the amount was changed to 60 parts by mass.

[Comparative Example 5]
In Comparative Example 3, in place of EPT-4 and EBR-1, the polymers described in Table 4 below were used, the amount of “Asahi # 60G” and the amount of “Diana Process Oil PW-380” A rubber kneaded material and a vulcanized molded body were obtained in the same manner as in Comparative Example 3 except that the amounts were changed to 150 parts by mass and 60 parts by mass, respectively.

<Evaluation of rubber kneaded product and vulcanized molded product>
The rubber kneaded materials and vulcanized molded body evaluation methods obtained in the above Examples and Comparative Examples are shown below. The results are shown in Table 3 or 4.

〔hardness〕
The hardness of the vulcanized molded body was measured according to JIS K6253. Specifically, the hardness was calculated | required with the durometer A using the vulcanization molding of thickness 12mm.

[Tensile breaking strength, tensile breaking elongation]
Using the vulcanized molded body, a tensile test was performed in accordance with JIS K6251 under conditions of a measurement temperature of 23 ° C. and a tensile speed of 500 mm / min, and the strength at break (TB) and elongation at break (EB) were measured.

(Tear strength)
From the rubber kneaded product, an angle-shaped test piece having a thickness of 2 mm is prepared under the same conditions as in the preparation of the vulcanized molded body, and the test piece is pulled at a speed of 500 mm / sec to obtain the maximum stress value (tear strength). Measured (measurement temperature 25 ° C.).

(Dynamic friction coefficient)
The dynamic friction coefficient of the vulcanized molded body was measured under the following conditions using a surface property measuring instrument [TRIBOGEAR TYPE: 14FW: manufactured by Shinto Chemical Co., Ltd.].
Indenter: glass plate polished in a semicircular shape in the width direction and thickness direction (height: 45 mm, width: 20 mm, thickness: 3 mm)
・ Load: 200g
・ Tensile speed: 200 mm / min

[Taber wear amount]
Abrasion resistance test According to JIS K6264, a Taber abrasion test of the vulcanized molded body was performed under the following conditions, and the amount of abrasion was measured.
-Grinding wheel: Load at the time of No. 1 flat test specified by JIS R 6211-3 (H18): 1000 g
-Test number of test pieces: 1000 times-Test piece thickness: 2.0 mm

〔gross〕
Based on JIS Z8741, a gloss meter (gross checker IG-310, incident angle 60 ° C., light receiving angle 60 ° C .: manufactured by HORIBA, Ltd.) was applied to the surface of the vulcanized molded article to measure the surface gloss.

〔Shrinkage factor〕
The rubber kneaded product was cross-linked at 180 ° C. for 5 minutes using a mold having a length of 150 mm × width of 150 mm × thickness of 2 mm, and then allowed to stand at 23 ° C. for 24 hours, and the lateral length (L: mm) was measured. The shrinkage percentage was calculated from the following equation.
Shrinkage rate (%) = (150−L) / 150 × 100

[Compression set (CS)]
The compression set of the vulcanized molded body was carried out under the following conditions based on JIS K6262. The thickness of the test piece before and after the test was measured, and compression set (CS) (%) was calculated from the following calculation formula.
Test temperature: 70 ° C or 100 ° C
Test time: 22 hours or 197 hours Compression set (CS) (%) = {(t ₀ -t ₁ ) / (t ₀ -t ₂ )} × 100
t ₀ : thickness of test specimen before test (mm)
t ₁ : thickness of the test piece removed from the compression device (mm)
t ₂ : Spacer thickness (mm)

[Roll processability]
Winding property to roll when kneaded rubber kneaded at 8 inch roll (front roll surface temperature 80 ° C., rear roll surface temperature 80 ° C., front roll rotation speed 16 rpm, rear roll rotation speed 18 rpm) Was evaluated according to the following criteria.
○: Wound on roll ×: Rubber kneaded material does not wind around the roll

[Extrudability]
The rubber kneaded product was extruded into a flat plate shape (3 cm width × 2 mm thickness) by a 50φ mm single screw extruder (manufactured by Mitsuba Corporation), and the extrudability (extruded design surface state) was evaluated in two stages according to the following criteria. .
○: Excellent smoothness and good surface appearance ×: Unevenness and waviness of a flat molded product are seen, and surface gloss is poor

Claims (10)

A rubber composition comprising an ethylene / α-olefin copolymer (A) satisfying the following requirement (a) and an ethylene / α-olefin / non-conjugated polyene copolymer rubber (B) satisfying the following requirement (b) ( However, the carbon number of the α-olefin in the copolymer (A) and the copolymer rubber (B) is 3 to 20).
(A) Melting | fusing point is 110 degrees C or less (b) Ratio Mw / Mn of the weight average molecular weight Mw calculated | required by GPC analysis and number average molecular weight Mn is 1.5-10.0. The rubber composition according to claim 1, wherein the copolymer (A) satisfies the following requirements (A1) and (A2).
(A1) The density is 0.840 to 0.920 g / cm ³ (A2) The MFR at 190 ° C. and 2.16 kg is 0.1 to 50 g / 10 min. The rubber composition according to claim 1 or 2, wherein the copolymer rubber (B) satisfies the following requirements (B1) to (B3).
(B1) The molar ratio of ethylene to an α-olefin having 3 to 20 carbon atoms (ethylene / α-olefin) is 50/50 to 90/10. (B2) The iodine value is 1 to 50 g / 100 g (B3 ) Intrinsic viscosity [η] measured in decalin at 135 ° C. is 0.5 to 7.0 dl / g   The blend mass ratio [(A) / (B)] of the copolymer (A) and the copolymer rubber (B) is 5/95 to 50/50. The rubber composition as described in 2.   The rubber composition according to any one of claims 1 to 4, comprising a foaming agent (C).   The crosslinked body obtained by bridge | crosslinking the rubber composition of any one of Claims 1-5.   The foam obtained by bridge | crosslinking and foaming the rubber composition of any one of Claims 1-5.   The automobile sealing material which consists of the crosslinked body of Claim 6, or the foam of Claim 7.   A door opening trim comprising the crosslinked body according to claim 6 or the foam according to claim 7.   A weatherstrip sponge comprising the foam according to claim 7.