JP2000119478A - Rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rubber composition which is excellent in the balance among softness, mechanical properties, and molding/processing properties and has good gas/water vapor permeability and vibration-damping properties by compounding an isobutylene block copolymer with a specified amount of butyl rubber. SOLUTION: 100 pts.wt. block copolymer comprising polymer blocks formed mainly from isobutylene and polymer blocks formed from a monomer component which does not contain isobutylene as the main monomer is compounded with 5-230 pts.wt. butyl rubber. The monomer component which does not contain isobutylene as the main monomer is preferably an aromatic vinyl monomer, preferable examples being styrene, α-methylstyrene, p-methylstyrene, and indene. The wt. ratio of polymer blocks formed mainly from isobutylene to polymer blocks formed from a monomer component which does not contain isobutylene as the main monomer is preferably (98/2)-(40/60).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rubber composition comprising a specific isobutylene block copolymer and a butyl rubber. More specifically, the present invention relates to a rubber composition having an excellent balance of flexibility, mechanical properties, and moldability / processability, and having good gas and water vapor barrier properties and vibration damping properties.

[0002]

2. Description of the Related Art Butyl rubber is widely used in various applications because of its excellent gas / steam barrier properties, vibration damping properties, and good resistance to heat, acids, bases, ozone and the like. However, the mechanical properties of the raw rubber before cross-linking (vulcanization) are not sufficient, and the rubber is usually used in a cross-linked (vulcanized) state after vulcanization.

In order to obtain a molded article made of vulcanized rubber,
Not only the operation of compounding the vulcanizing agent into the raw rubber but also the vulcanization operation by heat treatment after molding is required, and these operations require a great deal of labor and time. Further, vulcanized rubber has a narrow selection range of molding and processing methods, and the obtained molded product is difficult to reuse by heat treatment.

[0004] As a method for improving the strength and processability of butyl rubber in an unvulcanized state, JP-A-6-20009
No. 8 discloses a triblock copolymer composed of an aromatic vinyl polymer-polyisobutylene-aromatic vinyl polymer or a star block copolymer composed of an aromatic vinyl polymer-polyisobutylene with respect to butyl rubber. Attempts to formulate coalescence have been disclosed. However, the effect of improving the strength in the unvulcanized state is not great. On the other hand, in the case of vulcanization, the strength is improved but the moldability and workability are reduced. Therefore, in any case, the balance between mechanical strength and formability / workability was not sufficient.

[0005] A material called a thermoplastic elastomer is known as a recyclable rubber material which does not require a vulcanizing operation, is easy to mold, and is recyclable. Among thermoplastic elastomers, styrene-isobutylene-based block copolymers, in particular, have begun to attract attention as materials having excellent vibration damping properties, barrier properties, heat stability and the like. For example, WO-93
14135 discloses an attempt to use it as a vibration damping material, and JP-A-5-269201 discloses an attempt to use it as a medicine / medical container. As described above, application of the styrene-isobutylene-based block copolymer to various uses is being studied, but it is necessary to synthesize all styrene-isobutylene-based block copolymers having optimal flexibility for each use. Are often industrially disadvantageous.

As one method for imparting appropriate flexibility to the block copolymer, a plasticizer (softening agent) such as process oil or liquid polybutene may be added.
There have been problems that low molecular weight components bleed out and the barrier properties of gas and water vapor deteriorated.

[0007]

SUMMARY OF THE INVENTION In view of the above situation, the present invention provides a rubber composition having an excellent balance of flexibility, mechanical properties, moldability and workability, and good gas / steam barrier properties and vibration damping properties. It is an object of the present invention to provide a rubber composition which can provide sufficient mechanical properties even in an uncrosslinked state.

[0008]

That is, the present invention provides:
(A) 100 parts by weight of an isobutylene-based block copolymer composed of a polymer block containing isobutylene as a monomer main component and a polymer block containing no isobutylene as a monomer main component, and (b) 5-230 wt. It is a rubber composition containing a part.

Hereinafter, the present invention will be described in detail.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The rubber composition of the present invention comprises (a) an isobutylene-based block copolymer comprising a polymer block containing isobutylene as a main component and a polymer block containing no isobutylene as a main component. 100 parts by weight,
(B) 5-230 parts by weight of butyl rubber.

The (a) isobutylene-based block copolymer of the present invention has a polymer block containing isobutylene as a monomer main component and a polymer block containing no isobutylene as a monomer main component. If there is no particular limitation, for example, linear, branched, block copolymer having a star-like structure, diblock copolymer, triblock copolymer,
Any of a multi-block copolymer and the like can be selected.

The monomer component containing no isobutylene as the main component of the present invention refers to a monomer component having an isobutylene content of 30% by weight or less. The content of isobutylene in the monomer component containing no isobutylene as a main component is preferably 10% by weight or less, more preferably 3% by weight or less.

The monomer other than isobutylene in the monomer component containing no isobutylene as the main component of the present invention is not particularly limited as long as it is a cationically polymerizable monomer component. Monomers such as vinyls, dienes, vinyl ethers, silanes, vinyl carbazole, β-pinene, acenaphthylene and the like can be exemplified. These may be used alone or in combination of two or more.

The aliphatic olefin monomers include ethylene, propylene, 1-butene, 2-methyl-1-butene, 3-methyl-1-butene, pentene, hexene, cyclohexene, and 4-methyl-1-pentene. , Vinylcyclohexane, octene, norbornene and the like.
These may be used alone or in combination of two or more.

As the aromatic vinyl monomer, styrene, o-, m- or p-methylstyrene, α-methylstyrene, β-methylstyrene, 2,6-dimethylstyrene, 2,4-dimethylstyrene, α-methyl-o-methylstyrene, α-methyl-m-methylstyrene, α-methyl-p-methylstyrene, β-methyl-o-methylstyrene, β-methyl-m-methylstyrene, β-methyl-p -Methylstyrene, 2,4,6-trimethylstyrene, α-methyl-2,6-dimethylstyrene, α-methyl-2,4-dimethylstyrene, β-methyl-2,6-
Dimethylstyrene, β-methyl-2,4-dimethylstyrene, o-, m- or p-chlorostyrene, 2,6-dichlorostyrene, 2,4-dichlorostyrene, α-chloro-o-chlorostyrene, α- Chloro-m-chlorostyrene, α-chloro-p-chlorostyrene, β-chloro-
o-chlorostyrene, β-chloro-m-chlorostyrene, β-chloro-p-chlorostyrene, 2,4,6-trichlorostyrene, α-chloro-2,6-dichlorostyrene, α-chloro-2,4 -Dichlorostyrene, β-chloro-2,6-dichlorostyrene, β-chloro-2,4
-Dichlorostyrene, o-, m- or pt-butylstyrene, o-, m- or p-methoxystyrene, o-,
m- or p-chloromethylstyrene, o-, m- or p
-Bromomethylstyrene, a styrene derivative substituted with a silyl group, indene, vinylnaphthalene and the like. These may be used alone or in combination of two or more.

Examples of the diene monomer include butadiene, isoprene, hexadiene, cyclopentadiene, cyclohexadiene, dicyclopentadiene, divinylbenzene and ethylidene norbornene. These may be used alone or in combination of two or more.

The vinyl ether monomers include methyl vinyl ether, ethyl vinyl ether, (n-, iso) propyl vinyl ether, (n-, sec-, te
rt-, iso) butyl vinyl ether, methylpropenyl ether, ethylpropenyl ether and the like. These may be used alone or in combination of two or more.

Examples of the silane compound include vinyltrichlorosilane, vinylmethyldichlorosilane, vinyldimethylchlorosilane, vinyldimethylmethoxysilane, vinyltrimethylsilane, divinyldichlorosilane, divinyldimethoxysilane, divinyldimethylsilane, 1,3-
Examples thereof include divinyl-1,1,3,3-tetramethyldisiloxane, trivinylmethylsilane, γ-methacryloyloxypropyltrimethoxysilane, and γ-methacryloyloxypropylmethyldimethoxysilane.
These may be used alone or in combination of two or more. The monomer component not containing isobutylene as a main component of the present invention is preferably a monomer component containing an aromatic vinyl-based monomer as a main component in view of the balance between physical properties and polymerization characteristics. The aromatic vinyl-based monomer of the present invention indicates a monomer component having a content of aromatic vinyl-based monomer of 60% by weight or more, preferably 80% by weight or more. As the aromatic vinyl monomer, styrene, α-methylstyrene,
It is preferable to use at least one monomer selected from the group consisting of p-methylstyrene and indene, and it is particularly preferable to use styrene, α-methylstyrene, or a mixture thereof in terms of cost.

The monomer component containing isobutylene as a main component of the present invention may or may not contain a monomer other than isobutylene. Usually, isobutylene contains 60% by weight or more, preferably 80% by weight. It is a monomer component contained by weight or more. The monomer other than isobutylene is not particularly limited as long as it is a monomer capable of cationic polymerization, and examples thereof include the above-mentioned monomers.

The ratio of the polymer block containing isobutylene as a main component and the polymer block not containing isobutylene as a main component is not particularly limited. However, isobutylene is simply used in consideration of the balance between physical properties and processability. 98 to 40% by weight of a polymer block containing a monomer as a main component, and 2 to 60% of a polymer block containing no isobutylene as a monomer.
%, Preferably 95 to 50% by weight of a polymer block containing isobutylene as a monomer main component, and 5 to 50% by weight of a polymer block containing no isobutylene as a monomer main component. preferable.

The preferred structure of the (a) isobutylene-based block copolymer of the present invention is that an aromatic vinyl-based monomer is simply used in view of the mechanical properties, moldability, and other various physical properties of the obtained rubber composition. Polymer block mainly composed of monomer-polymer block mainly composed of isobutylene as monomer-
A triblock copolymer having a structure of a polymer block containing an aromatic vinyl monomer as a main component, and a polymer block containing an isobutylene monomer as a main component and an aromatic vinyl monomer as a single unit. Triblock copolymer having a structure of a polymer block having a polymer main component-isobutylene as a monomer main component, and a polymer block having an aromatic vinyl monomer as a monomer main component -A diblock copolymer having a structure of a polymer block containing isobutylene as a monomer main component, and a polymer block containing an aromatic vinyl monomer as a monomer main component-isobutylene as a monomer main component. It is at least one selected from the group consisting of star polymers having a diblock copolymer having a structure of a polymer block as a component as an arm.

(A) The number average molecular weight of the isobutylene-based block copolymer is not particularly limited.
From the viewpoint of physical properties and the like, it is preferably 3,000 to 1,000,000, and particularly preferably 5,000 to 500,000. If the number average molecular weight of the isobutylene-based block copolymer is lower than the above range, the physical properties of the rubber composition are not sufficiently exhibited, while if it exceeds the above range, it is disadvantageous in terms of fluidity and processability. .

For the purpose of improving the viscosity and adhesion properties of the rubber composition of the present invention and the compatibility with polar resins, (a) isobutylene-based block copolymers having various functional groups in the molecular chain or at the terminal of the molecular chain. Those having a group can be used.
Examples of the functional group include an epoxy group, a hydroxyl group, an amino group, an alkylamino group, an ester group such as an alkoxyl group, a carboxyl group, an ester group such as an alkoxycarbonyl group, an acyloxyl group, a carbamoyl group, an alkylcarbamoyl group, and an acylamino group. Amide group, acid anhydride group such as maleic anhydride, silyl group, allyl group, vinyl group and the like. The isobutylene-based block copolymer may have only one of these functional groups, or may have two or more of these functional groups. Preferred functional groups from the viewpoint of physical balance include an epoxy group, an amino group, an ether group, an ester group, an amide group, a silyl group, an allyl group, and a vinyl group.

(A) The method for producing the isobutylene-based block copolymer is not particularly limited, and a known polymerization method can be used. To obtain a block copolymer having a controlled structure, the following method is used. In the presence of the compound represented by the general formula (1), it is preferable to polymerize a monomer component containing no isobutylene as a main component such as a monomer containing isobutylene as a main component and an aromatic vinyl monomer. .

[0025]

Embedded image (In the formula, X represents a halogen atom, an alkoxyl group having 1 to 6 carbon atoms or an acyloxyl group. A plurality of R ^{1 s} are the same or different and are a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms. R ² represents a monovalent or polyvalent aromatic hydrocarbon group or a monovalent or polyvalent aliphatic hydrocarbon group, n represents an integer of 1 to 6, and n is 2 or more. And a plurality of Xs may be the same or different.) Examples of the halogen atom include chlorine, fluorine, bromine and iodine. The alkoxyl group having 1 to 6 carbon atoms is not particularly limited, and includes, for example, a methoxy group, an ethoxy group, an n- or isopropoxy group, and the like. The above-mentioned acyloxyl group having 1 to 6 carbon atoms is not particularly limited, and examples thereof include an acetyloxy group and a propionyloxy group. The hydrocarbon group having 1 to 6 carbon atoms is not particularly limited, and examples thereof include a methyl group, an ethyl group, and n-
Or an isopropyl group.

The compound represented by the above general formula (1) serves as an initiator and generates a carbon cation in the presence of a Lewis acid or the like, and is considered to be a starting point of cationic polymerization. Examples of the compound represented by the general formula (1) used in the present invention include the following compounds.

(1-chloro-1-methylethyl) benze
[C₆H_FiveC (CH_Three)_TwoCl], 1,4-bis (1-k
Rolo-1-methylethyl) benzene [1,4-Cl (C
H _Three)_TwoCC₆H_FourC (CH_Three)_TwoCl], 1,3-bis (1
-Chloro-1-methylethyl) benzene [1,3-Cl
(CH_Three)_TwoCC₆H_FourC (CH_Three)_TwoCl], 1,3,5-
Tris (1-chloro-1-methylethyl) benzene
[1,3,5- (ClC (CH_Three)_Two)_ThreeC₆H_Three], 1,
3-bis (1-chloro-1-methylethyl) -5- (t
ert-butyl) benzene [1,3- (C (CH_Three)_TwoC
l)_Two-5- (C (CH_Three)_Three) C₆H_ThreeAmong them, particularly preferred is 1-chloro-1-methyi.
Ruethylbenzene [C ₆H_FiveC (CH_Three)_TwoCl], bis
(1-Chloro-1-methylethyl) benzene [C ₆H
_Four(C (CH_Three)_TwoCl)_Two], Tris (1-chloro-1-
Methylethyl) benzene [(ClC (CH_Three)_Two)_ThreeC₆H
_Three]. 1-chloro-1-methylethylbenzene
Is α-chloroisopropylbenzene, 2-chloro-
Also called 2-propylbenzene or cumyl chloride
Bale, bis (1-chloro-1-methylethyl) benzene
Is bis (α-chloroisopropyl) benzene, bis
(2-chloro-2-propyl) benzene or dicum
Tris (1-chloro-1-me)
Tylethyl) benzene is tris (α-chloroisopro
Pill) benzene, tris (2-chloro-2-propyl)
Also called benzene or tricumyl chloride.

In the above polymerization reaction, a Lewis acid catalyst can coexist. Any Lewis acid may be used as long as it can be used for cationic polymerization. TiCl ₄ , TiBr
₄ , BCl ₃ , BF ₃ , BF ₃ .OEt ₂ , SnCl ₄ , SbCl ₅ ,
SbF ₅ , WCl ₆ , TaCl ₅ , VCl ₅ , FeCl ₃ , ZnB
metal halides such as r ₂ , AlCl ₃ , AlBr ₃ ; Et ₂
Organometal halides such as AlCl and EtAlCl ₂ can be suitably used. Above all, considering the ability as a catalyst and industrial availability, TiCl ₄ , B
Cl ₃ and SnCl ₄ are preferred.

The amount of the Lewis acid catalyst to be used is not particularly limited, and can be set in consideration of the polymerization characteristics or polymerization concentration of the monomer used.

In the above polymerization reaction, if necessary, an electron donor component can be further coexisted. This electron donor component is considered to have an effect of stabilizing the growing carbon cation during cationic polymerization,
The addition of an electron donor produces a polymer having a controlled structure with a narrow molecular weight distribution. The usable electron donor component is not particularly limited, and examples thereof include pyridines, amines, amides, sulfoxides, esters, and metal compounds having an oxygen atom bonded to a metal atom.

The above-mentioned polymerization reaction can be carried out in an organic solvent, if necessary, and any organic solvent can be used without any particular limitation as long as it does not substantially inhibit cationic polymerization. Specifically, halogenated hydrocarbons such as methyl chloride, dichloromethane, chloroform, ethyl chloride, dichloroethane, n-propyl chloride, n-butyl chloride, and chlorobenzene; benzene, toluene, xylene,
Alkylbenzenes such as ethylbenzene, propylbenzene, and butylbenzene; linear aliphatic hydrocarbons such as ethane, propane, butane, pentane, hexane, heptane, octane, nonane, and decane; 2-methylpropane;
2-methylbutane, 2,3,3-trimethylpentane,
Branched aliphatic hydrocarbons such as 2,2,5-trimethylhexane; cycloaliphatic hydrocarbons such as cyclohexane, methylcyclohexane and ethylcyclohexane; paraffin oil obtained by hydrogenating and purifying a petroleum fraction. it can.

These solvents are used alone or in combination of two or more in consideration of the balance between the polymerization characteristics of the monomers constituting the block copolymer and the solubility of the resulting polymer.

The amount of the above-mentioned solvent to be used is adjusted so that the concentration of the polymer is 1 to 5 in consideration of the viscosity of the obtained polymer solution and the ease of heat removal.
It is determined to be 50 wt%, preferably 3 to 35 wt%.

In conducting the actual polymerization, the respective components are mixed at a temperature of, for example, -100 ° C. or more and less than 0 ° C. under cooling. A particularly preferred temperature range is from -30C to -80C in order to balance the energy cost with the stability of the polymerization.

The above-mentioned polymerization reaction may be carried out in a batch system (batch system or semi-batch system), or may be carried out in a continuous system in which each component required for the polymerization reaction is continuously added into a polymerization vessel.

Further, a star block having arms formed of a diblock copolymer formed from a polymer block composed mainly of an aromatic vinyl monomer and a polymer block composed mainly of isobutylene as a monomer. The method for producing the polymer is not particularly limited. For example, a monomer containing an aromatic vinyl monomer as a main component and isobutylene as a main component in the presence of a compound having three or more cationic polymerization initiation points. A method of polymerizing a monomer component to produce a diblock copolymer by polymerizing a monomer component mainly containing an aromatic vinyl monomer and a monomer component mainly containing isobutylene, Thereafter, a method of coupling (bonding) the diblock copolymer using a polyfunctional compound as a coupling agent (binder), and the like, may be mentioned.

As the polyfunctional compound, a compound having three or more coupling points (functional groups) per molecule can be used. 2 per molecule
If the compound having two reaction points can form a polymer by polymerizing or reacting to have three or more reaction points (functional groups), use of the compound does not hinder use.

Examples of such polyfunctional compounds include, for example, 1,3-divinylbenzene, 1,4-divinylbenzene, 1,2-diisopropenylbenzene, 1,3-diisopropenylbenzene, 1,4 -Diisopropenylbenzene, 1,3-divinylnaphthalene, 1,8-divinylnaphthalene, 2,4-divinylbiphenyl, 1,2-
Divinyl aromatic compounds such as divinyl-3,4-dimethylbenzene, 1,3-divinyl-4,5,8-tributylnaphthalene, and 2,2′-divinyl-4-ethyl-4′-propylbiphenyl; 2,4-trivinylbenzene, 1,3,5-trivinylnaphthalene, 3,5
Trivinyl aromatic compounds such as 4'-trivinyl biphenyl and 1,5,6-trivinyl-3,7-diethylnaphthalene; cyclohexane diepoxide, 1,4-pentane diepoxide, 1,5-hexane diepoxide and the like Diepoxides; diketones such as 2,4-hexane-dione, 2,5-hexane-dione, 2,6-heptane-dione; 1,4-butanedial, 1,5-pentanedial, 1,6-hexanedial Dialdehydes such as;
Examples include siloxane compounds and calixarene. These may be used alone or in combination of two or more.

Of these, divinyl aromatic compounds are preferably used in view of reactivity, physical properties of the obtained star polymer, and the like, and particularly preferred are 1,3-divinylbenzene, 1,4-divinylbenzene, It is at least one selected from the group consisting of 3-diisopropenylbenzene and 1,4-diproisophenylbenzene. The above compound is usually commercially available as a mixture with, for example, ethyl vinyl benzene, and the divinyl aromatic compound can be used as it is if it is the main component. May be used.

The (b) butyl rubber of the present invention has 4 carbon atoms.
It is a copolymer of an isoolefin of 6 to 6 and a conjugated diene compound of 4 to 8 carbon atoms. If necessary, a copolymer of another monomer can be used, and a halogenated one can also be used. . Preferred butyl rubbers include butyl rubber composed of 95 to 99.5% by weight of isobutylene and 0.5 to 5% by weight of isoprene, or halogenated butyl rubber obtained by halogenating butyl rubber. Preferred halogenated butyl rubbers include chlorinated butyl rubber and brominated butyl rubber. Apart from isoolefins having 4 to 6 carbon atoms and conjugated diene compounds having 4 to 8 carbon atoms, styrene, p
-A butyl rubber obtained by copolymerizing a small amount of an aromatic vinyl monomer such as methylstyrene can also be used.

The number average molecular weight of the butyl rubber is not particularly limited, but is preferably 50,000 or more,
More preferably, it is 0000 or more.

These polymers may have a functional group as required. The functional group is not particularly limited, and may be the same as those described above.

The proportion of (a) the isobutylene-based block copolymer and (b) butyl-based rubber is 5 to 230 parts by weight, preferably 1 to 100 parts by weight of (a).
0 to 200 parts by weight, more preferably 20 to 150 parts by weight. When the amount of (b) is less than 5 parts by weight, it is impossible to obtain a suitable flexibility, and the (a) substantially has a single property. On the other hand, when (b) exceeds 230 parts by weight, sufficient mechanical properties cannot be obtained in an uncrosslinked state, and conversely, in a crosslinked state, the molding and processing properties are reduced, and good physical properties and molding and processing are not obtained. Workability balance cannot be obtained.

Since the rubber composition of the present invention can provide sufficient mechanical properties even in an uncrosslinked state, it is excellent in balance between mechanical properties and moldability / processability. In the present invention, even when the rubber composition is crosslinked, mechanical strength, compression set, heat resistance and the like are improved while maintaining good moldability and processability. Crosslinking in this case means producing a chemical bond in the presence of an organic peroxide, sulfur or a suitable crosslinking agent and, if necessary, a crosslinking aid and / or a crosslinking accelerator.

The gel fraction of the rubber composition of the present invention can be adjusted depending on the degree of crosslinking, and can be set in view of desired physical properties and moldability / processability. The preferred gel fraction is 90% or less, more preferably 80% or less, particularly preferably 50% or less. Outside this range, the moldability and processability of the rubber composition deteriorates. The gel fraction can be measured using a solvent that can dissolve the rubber composition without performing crosslinking. Such a solvent is not particularly limited, and examples thereof include toluene, xylene, and chloroform.

The hardness of the rubber composition of the present invention can be appropriately set according to the intended use, and is not particularly limited. Generally, the hardness (JIS-A) measured according to JIS K6253 is 3. It is preferably from 95 to 95, and more preferably from 5 to 90.

Further, a filler may be added to the rubber composition of the present invention. Suitable fillers include clay, diatomaceous earth, silica, talc, barium sulfate, calcium carbonate, magnesium carbonate, metal oxides, mica, graphite, scaly inorganic fillers such as aluminum hydroxide,
Examples include various metal powders, wood chips, glass powders, ceramic powders, carbon black, granular or powdery solid fillers such as granular or powdery polymers, and other various natural or artificial short fibers and long fibers. In addition, a hollow filler, for example, an inorganic hollow filler such as a glass balloon and a silica balloon, and an organic hollow filler made of polyvinylidene fluoride and a polyvinylidene fluoride copolymer can be blended.

The amount of the filler is from 0 to 200 parts by weight, preferably from 0 to 100 parts by weight, based on 100 parts by weight of the total of the components (a) and (b) constituting the rubber composition of the present invention. Department. If the amount exceeds 200 parts by weight, the physical properties of the obtained rubber composition are reduced. The rubber composition of the present invention may contain at least one of an antioxidant and an ultraviolet absorber, if necessary. The compounding amount is based on 100 parts by weight of the total of components (a) and (b).
0.000001 to 20 parts by weight, preferably 0.000
01 to 10 parts by weight.

The rubber composition of the present invention has rigidity, processability,
A thermoplastic resin can be blended for the purpose of improving heat resistance and the like.

The thermoplastic resin is not particularly limited and can be appropriately selected in consideration of desired physical properties and workability. Examples thereof include a polycarbonate resin, a polyphenylene ether resin, and an aromatic vinyl compound resin. Resin, polyolefin resin, polyvinyl chloride resin, polyvinyl oxide resin, poly (meth) acrylate resin, poly (meth) acrylamide resin, poly (meth) acrylonitrile resin, polyamide resin, polyester resin, Examples include polyacetal resins, polysulfone resins, polyarylene sulfide resins, fluorine resins, polyimide resins, thermoplastic polyurethane resins, and the like. Of these, at least one selected from the group consisting of polyolefin-based resins, aromatic vinyl compound-based resins, and polyphenylene ether-based resins is preferably used in view of compatibility with the component (a) or the component (b). Can be

Examples of the polyolefin resin include an α-olefin homopolymer, a random copolymer, a block copolymer and a mixture thereof, or a random copolymer of an α-olefin with another unsaturated monomer, Block copolymers, graft copolymers and oxidized, halogenated or sulfonated products of these polymers can be used alone or in combination of two or more. Specifically, polyethylene, ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate Copolymer, ethylene-vinyl alcohol copolymer, ethylene-ethyl acrylate copolymer, chlorinated polyethylene, polyethylene resin such as ethylene-styrene copolymer, isotactic polypropylene, syndiotactic polypropylene, propylene-ethylene random Examples thereof include copolymers, propylene-ethylene block copolymers, polypropylene resins such as chlorinated polypropylene, polymethylpentene, (co) polymers of cyclic olefins, and the like. Of these, polyethylene-based resins, polypropylene-based resins, and (co) polymers of cyclic olefins can be preferably used in view of cost and balance of physical properties of the thermoplastic resin. These may be used alone or in combination of two or more.

As the polyphenylene ether-based resin,
Poly (2,6-dimethyl-1,4-phenylene) ether, poly (2-methyl6-ethyl-1,4-phenylene) ether, poly (2,6-dibutyl-1,4-phenylene) ether, poly (2,6-diphenyl-1,4
-Phenylene) ether, poly (2,6-dimethoxy-)
1,4-phenylene) ether, poly (2,6-dichloro-1,4-phenylene ether), a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, 2,6-dimethyl Phenol and 2,3,5
Copolymers of 6-tetramethylphenol and the like can be mentioned. Further, a modified polyphenylene ether-based resin such as one obtained by graft copolymerization of styrene can also be used.

Examples of the aromatic vinyl resin include polystyrene, syndiotactic polystyrene, high impact polystyrene, poly α-methylstyrene, poly p-methylstyrene, styrene-maleic anhydride copolymer, and styrene-methyl methacrylate copolymer. And the like.

The amount of the thermoplastic resin is from 0 to 100 parts by weight based on 100 parts by weight of the rubber composition of the present invention.
If it exceeds 100 parts by weight, the flexibility tends to be low and the balance with the mechanical strength and the like tends to be poor.

Further additives such as flame retardants, antibacterial agents,
Light stabilizers, colorants, flow improvers, lubricants, antiblocking agents, antistatic agents, crosslinking agents, crosslinking aids and the like can be added. These may be used alone or in combination of two or more.

The method for producing the rubber composition of the present invention is not particularly limited, and a known method can be applied. For example, it can be manufactured by mixing the above components using a roll, a Banbury mixer, a Brabender, a kneader, a high shear mixer, a single or twin screw extruder, or the like.

The crosslinking method is not particularly limited. For example, after a component (a) and a component (b) are mixed to produce a rubber composition, an organic peroxide, sulfur, or another suitable compound may be used. A method of crosslinking by adding a crosslinking agent and, if necessary, a crosslinking assistant and / or a crosslinking accelerator, component (a) and component (b)
A method of adding an organic peroxide, sulfur or other suitable crosslinking agent, and optionally a crosslinking aid and / or a crosslinking accelerator, and crosslinking simultaneously with the production of the rubber composition, or a component ( A method of mixing the component (a) after crosslinking the b) and the like can be exemplified.

[0058]

The present invention will be described more specifically with reference to the following examples. It should be noted that the present invention is not limited in any way by these embodiments, and can be appropriately changed and implemented without changing the gist thereof. (Reference Example 1) Production of styrene-isobutylene-styrene block copolymer) In a 10 L reaction vessel equipped with a stirrer, 2166 mL of methylcyclohexane (dried by molecular sieves), 1634 mL of methylene chloride (dried by molecular sieves), p- 1.756 g of dicumyl chloride was added. After cooling the reaction vessel to -70 ° C, α-picoline (2-methylpyridine) 0.75
mL and 632 mL of isobutylene were added. Further, 30 mL of titanium tetrachloride was added to initiate polymerization, and the mixture was reacted at -70 ° C for 1.5 hours while stirring the solution. Then, 270 mL of styrene was added to the reaction solution, and the reaction was further continued for 20 minutes. Then, a large amount of methanol was added to stop the reaction. After removing the solvent and the like from the reaction solution, the polymer was dissolved in toluene and washed twice with water. This toluene solution was added to an acetone-methanol mixture to precipitate a polymer,
The obtained polymer was vacuum-dried at 60 ° C. for 24 hours to obtain an isobutylene-based block copolymer (hereinafter referred to as S
IBS).

The number average molecular weight of the obtained isobutylene block copolymer was 89,000, and the molecular weight distribution was 1.18. The number average molecular weight is 5 from Waters.
It was measured by a 10-type GPC system (chloroform was used as a solvent, and the flow rate was 1 mL / min), and the value in terms of polystyrene was shown.

Example 1 SIBS manufactured in Reference Example 1
100 parts by weight, 50 parts by weight of a butyl rubber having a number average molecular weight of 206,000 (butyl 365, manufactured by JSR), and 0.5 part of Irganox 1010 (manufactured by Ciba Geigy) at 170 ° C.
Was kneaded with a Labo Plastomill (manufactured by Toyo Seiki Co., Ltd.) for 15 minutes to produce a rubber composition. The gel fraction of the obtained rubber composition was less than 1%. 170 parts of the rubber composition
The sheet was produced by compression molding at ℃. The moldability was extremely good. A dumbbell-shaped test piece was cut out from the sheet, and the hardness (JIS-A) was measured according to JIS K6253. Further, tensile elongation at break and tensile strength at break were measured in accordance with JIS K6251.

As a result of the above evaluation, the hardness of the rubber composition of the present invention was 31, the tensile elongation at break was 770%, and the tensile strength at break was 9
It was 4 kg / cm ² , and was excellent in flexibility and mechanical properties.

Further, the rubber composition of the present invention has a vibration damping property, oxygen,
The barrier properties against carbon dioxide and water vapor were also good.

(Comparative Example 1) SIBS produced in Reference Example 1
100 parts by weight, paraffinic process oil (PW-3
80, manufactured by Idemitsu Kosan Co., Ltd.) 100 parts by weight, Irganox 1
010 (manufactured by Ciba Geigy) was kneaded with a Labo Plastomill (manufactured by Toyo Seiki) for 40 minutes at 170 ° C. to produce a rubber composition. 170 ° C.
To form a sheet. Bleed out of process oil was seen on the sheet surface.

A dumbbell-shaped test piece was cut out from the sheet, and the hardness (JIS-A), tensile elongation at break, and tensile strength at break were measured in the same manner as in Example 1.

As a result of the above evaluation, the hardness of the rubber composition was 9, the tensile elongation at break was 613%, and the tensile strength at break was 29 kg.
/ Cm ² , which is excellent in flexibility but markedly decreases mechanical properties.

[0066]

The rubber composition of the present invention has an excellent balance of flexibility, mechanical properties, moldability and processability, and good gas / steam barrier properties and vibration damping properties. Furthermore, there is no bleed-out of plasticizer, so it can be used for food, daily goods, toys,
Sports equipment use, stationery use, car interior and exterior use, civil engineering sheet, waterproof sheet, gasket, etc. civil engineering and construction use, AV
・ Household appliance use, OA / office equipment use, clothing / footwear use, textile use, medical use such as various catheters, containers, caps, etc., sanitary goods such as disposable diapers and sanitary goods, packaging and transportation materials, wire coating, cables and connectors.・ It can be used for electric wires such as plugs.

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Claims (13)

[Claims] (1) 100 parts by weight of an isobutylene-based block copolymer comprising (a) a polymer block containing isobutylene as a monomer main component and a polymer block containing no isobutylene as a monomer main component; A rubber composition containing 5-230 parts by weight of rubber. 2. The rubber composition according to claim 1, wherein the polymer block not containing isobutylene as a monomer main component contains an aromatic vinyl monomer as a monomer main component. 3. The rubber composition according to claim 2, wherein the proportion of the polymer block containing an aromatic vinyl-based monomer as a main component is 5 to 50% by weight of the whole isobutylene-based block copolymer. . 4. The aromatic vinyl monomer is styrene, p-
The rubber composition according to claim 2, wherein the rubber composition is at least one selected from the group consisting of methylstyrene, α-methylstyrene, and indene. 5. The (a) isobutylene-based block copolymer is a polymer block composed mainly of an aromatic vinyl monomer as a monomer main component-a polymer block composed mainly of isobutylene as a monomer main component-aromatic. Triblock copolymer having a structure of a polymer block containing a vinyl monomer as a main component, a polymer block containing isobutylene as a main component and an aromatic vinyl monomer as a monomer Triblock copolymer having a structure of a polymer block having a main component of polymer block-isobutylene as a main component, and a polymer block-isobutylene having an aromatic vinyl monomer as a main component. A diblock copolymer having a structure of a polymer block containing a monomer as a main component, and a polymer block containing an aromatic vinyl monomer as a monomer main component-isobutylene as a monomer main component. Polymerization 5. The rubber composition according to claim 2, wherein the rubber composition is at least one selected from the group consisting of star polymers having a diblock copolymer having a body block structure as an arm. 6. The method according to claim 1, wherein (b) the butyl rubber is at least one selected from the group consisting of butyl rubber, chlorinated butyl rubber, and brominated butyl rubber.
Or the rubber composition according to 5. 7. (b) The butyl rubber has a number average molecular weight of 5
The rubber composition according to claim 1, 2, 3, 4, 5, or 6, which has a molecular weight of 0000 or more. 8. The (b) butyl rubber has a number average molecular weight of 1
The rubber composition according to claim 7, which is not less than 00000. 9. The rubber composition according to claim 1, wherein the rubber composition is crosslinked. 10. The rubber composition according to claim 1, wherein the gel fraction is 80% or less. 11. The method according to claim 1, wherein the gel fraction is 50% or less.
The rubber composition according to 0. 12. The rubber composition according to claim 1, further comprising a filler. 13. The method according to claim 1, further comprising at least one of an antioxidant and an ultraviolet absorber.
The rubber composition according to 4, 5, 6, 7, 8, 9, 10, 11 or 12.