JP2003201373A - Rubber composition, its production process and molded rubber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber composition wherein a rubbery polymer compound and a laminar inorganic compound are uniformly dispersed, a process for producing the rubber composition, and a molded rubber obtained from the rubber composition. <P>SOLUTION: The rubber composition is obtained by a process comprising the step of preparing a mixture by mixing a polymer dispersion comprising a dispersion of a rubbery polymer compound such as an acrylonitrile rubber with an inorganic compound dispersion comprising a dispersion of a laminar inorganic compound such as a swelling mica, and the step of recovering a rubber composition from the mixture by using a cationic substance and a polyvalent metal salt to solidify the rubbery polymer compound and the laminar inorganic compound together. The obtained rubber composition has a low degree of shrinkage on crosslinking, can give a flat sheet, and exhibits a sufficient reinforcing effect, so that it is suitable for a vibration-damping material or the like. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rubber composition in which a rubber-based polymer and a layered inorganic compound are uniformly dispersed, and it is possible to obtain a smooth sheet with little shrinkage during crosslinking. Further, the present invention relates to a rubber composition having a sufficient reinforcing effect, a method for producing the same, and a rubber molded article. The present invention relates to a rubber for a constraining plate used for a vibration damper, a rubber for a tire used as an inner liner, an oil hose requiring oil resistance, a hose such as a fuel hose, a gas hose and a brake hose, and these hoses. It is widely used for covers, industrial parts such as belts and oil seals.

[0002]

2. Description of the Related Art In recent years, attempts have been made to obtain materials in which an inorganic compound is dispersed in various polymer materials. As such a technique, a method of forcibly mixing an organically modified clay mineral into rubber has been disclosed (JP-A-10-817).
No. 85 and Japanese Patent Laid-Open No. 2000-159937).

The above-mentioned publication discloses a technique for improving the compatibility between the clay minerals by organically modifying the clay minerals and dispersing the organically modified clay minerals in the rubber. However, its dispersibility is not sufficient. Further, a layered inorganic compound which is not organically modified is dispersed in rubber, but its dispersibility is not sufficient.

Further, in a recent mechanical device, the vibration of the machine is transmitted to the panels due to the rotational movement and the reciprocating movement, and in some cases, a large solid transmission sound is generated. In order to reduce this solid sound, a damping material is used in the vibrating part of the panel. In particular, there is a demand for quieting the inside of a car, which is strongly required to reduce noise. As a vibration damping material, noise in an automobile is small, and further, workability in manufacturing is desired from the viewpoint of cost reduction.

There are a restraint type and a non-restraint type in this damping material. The restraining type with better damping performance is a base (mostly metal) -damping material (elastic layer) -constraint plate (high rigidity). Material) and the damping performance varies depending on the performance of the restraint plate. The constraining plate needs to obtain high rigidity after undergoing a heat crosslinking process together with the vibration damping material, but at that time, it is necessary to deform in accordance with the adhesion to the vibration damping material and the deformed portion of the base during crosslinking. . However, the conventional constraining plate has a problem that adhesion and thermal deformability are not sufficient. In particular, when the vibration damping filler is contained in the rubber, there is a problem that the unvulcanized rubber sheet largely shrinks, the smoothness of the rubber sheet is deteriorated, and a gap is formed between the constraining plate and the vibration damping material. However, this problem has not been sufficiently solved by adding a silane coupling agent or the like.

[0006]

DISCLOSURE OF THE INVENTION The present invention is capable of solving the above-mentioned problems, and is a production method capable of uniformly dispersing a rubber-based polymer and a layered inorganic compound,
Further, it is possible to provide a rubber composition which can obtain a smooth sheet with less shrinkage at the time of cross-linking, and further has sufficient reinforcing effect such as improvement in tensile strength, a method for producing the same, and a rubber molded article. To aim.

[0007]

The present invention provides the following rubber composition, method for producing the same, and a rubber molded article. (1) A mixed solution preparation step of preparing a mixed solution containing a rubber-based polymer and a layered inorganic compound, and recovering a rubber composition containing the rubber-based polymer and the layered inorganic compound from the mixed solution A method for producing a rubber composition, comprising a recovery step. (2) The rubber as described in (1) above, which is obtained by mixing the polymer dispersion liquid in which the rubber-based polymer is dispersed and the inorganic compound dispersion liquid in which the layered inorganic compound is dispersed. A method for producing a composition. (3) The method for producing a rubber composition according to (2), wherein both the polymer dispersion and the inorganic compound dispersion are aqueous. (4) The method for producing a rubber composition according to (2), wherein the polymer dispersion and the inorganic compound dispersion are both non-aqueous and the layered inorganic compound is modified with an organic group. (5) In the recovering step, each electrolyte aqueous solution containing one or both of a cation-based substance and a polyvalent metal salt is brought into contact with the mixed liquid, and the mixed liquid is mixed with the cation-based substance and the polyvalent metal salt. The method for producing a rubber composition according to any one of (1) to (4) above, which comprises a co-coagulation step of co-coagulating the rubber-based polymer and the layered inorganic compound. (6) The rubber polymer is an acrylonitrile rubber,
Production of the rubber composition according to any one of (1) to (5), which is at least one selected from the group consisting of acrylic rubber, ethylene-α-olefin rubber, butyl rubber, and conjugated diene rubber. Method. (7) The layered inorganic compound is swellable mica, montmorillonite, bentonite, saponite, hectorite,
The rubber according to (1), (2), (5) or (6) above, which is at least one of organically modified swelling mica, organically modified montmorillonite, organically modified bentonite, organically modified saponite and organically modified hectorite. A method for producing a composition. (8) The method for producing a rubber composition according to any one of (5) to (7) above, wherein the cationic substance is at least one of a cationic polymer compound and a cationic surfactant. (9) A rubber composition obtained by the method for producing a rubber composition according to any one of (1) to (8) above. (10) A rubber molded product obtained by molding the rubber composition according to (9) above.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. [1] Rubber-based polymer This “rubber-based polymer” refers to a compound capable of exhibiting rubber elasticity by cross-linking and a polymer compound capable of exerting rubber elasticity without requiring cross-linking. As this rubber-based polymer, acrylonitrile-based rubber, acrylic-based rubber,
Examples thereof include ethylene-α-olefin rubber, butyl rubber, conjugated diene rubber, and other rubbers.
Only one of these may be used, or two or more may be used in combination.

(1) Acrylonitrile rubber This "acrylonitrile rubber" is a copolymer rubber of unsaturated nitrile monomer and conjugated diene monomer, unsaturated nitrile monomer, conjugated diene monomer and nitrile. Examples thereof include a copolymer rubber with a copolymerizable monomer having a polar group other than the group, and further, a partially cross-linked copolymer rubber thereof.

The unsaturated nitrile monomer is not particularly limited as long as it is an unsaturated monomer having a nitrile group. For example, acrylonitrile, methacrylonitrile,
Examples thereof include α-ethylacrylonitrile, α-isopropylacrylonitrile, α-chloroacrylonitrile, α-fluoroacrylonitrile and ethacrylonitrile. Of these, acrylonitrile is preferred. Of these, only one kind may be used, or two or more kinds may be used in combination.

The conjugated diene monomer is not particularly limited as long as it is a conjugated diene monomer. For example, butadiene, isoprene, 1,3-hexadiene, 2-methyl-1,3-butadiene, 2, 3-dimethylbutadiene, 2-trimethoxysilyl-1,3-butadiene,
1,3-pentadiene, 2,4-dimethyl-1,3-butadiene and the like can be mentioned. Of these, butadiene and isoprene are preferable. Of these, only one kind may be used, or two or more kinds may be used in combination.

As the copolymerizable monomer having a polar group other than the nitrile group, mention may be made of a monomer having at least one of a hydroxyl group, an epoxy group, an amino group, a carboxyl group and an alkoxysilyl group. You can
Examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate and 3-hydroxybutyl. Hydroxyalkyl (meth) acrylates such as (meth) acrylate and 4-hydroxybutyl (meth) acrylate; polyalkylene glycols such as polyethylene glycol and polypropylene glycol (the number of alkylene glycol units is, for example, 2 to 23) mono (meth) ) Acrylates, N-
Hydroxymethyl (meth) acrylamide, N- (2-
Hydroxyethyl) (meth) acrylamide, N, N-
Hydroxyl group-containing unsaturated amides such as bis (2-hydroxyethyl) (meth) acrylamide, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, o-hydroxy-α-methylstyrene, m-
Hydroxy-α-methylstyrene, p-hydroxy-α
Examples thereof include hydroxyl group-containing vinyl aromatic compounds such as methylstyrene and p-vinylbenzyl alcohol, and (meth) allyl alcohol. Of these, hydroxyalkyl (meth) acrylates and hydroxyl group-containing vinyl aromatic compounds are preferable. Of these, only one kind may be used, or two or more kinds may be used in combination.

Examples of the monomer having an epoxy group include (meth) allyl glycidyl ether, glycidyl (meth) acrylate, and 3,4-oxycyclohexyl (meth) acrylate. Of these, only one kind may be used, or two or more kinds may be used in combination.

Examples of the monomer having an amino group include a monomer having at least one of a primary amino group, a secondary amino group and a tertiary amino group. Of these, a monomer having a tertiary amino group is preferable, and dimethylaminomethyl (meth) acrylate, diethylaminomethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth).
Acrylate, 2- (di-n-propylamino) ethyl (meth) acrylate, 2-dimethylaminopropyl (meth) acrylate, 2-diethylaminopropyl (meth) acrylate, 2- (di-n-propylamino) propyl (meth ) Dialkylaminoalkyl (meth) acrylates such as acrylate, 3-dimethylaminopropyl (meth) acrylate, 3-diethylaminopropyl (meth) acrylate, 3- (di-n-propylamino) propyl (meth) acrylate, N- Dimethylaminomethyl (meth) acrylamide, N-diethylaminomethyl (meth) acrylamide, N- (2-dimethylaminoethyl) (meth) acrylamide, N- (2
-Diethylaminoethyl) (meth) acrylamide, N
-(2-Dimethylaminopropyl) (meth) acrylamide, N- (2-diethylaminopropyl) (meth) acrylamide, N- (3-dimethylaminopropyl)
In addition to N-dialkylaminoalkyl group-containing unsaturated amides such as (meth) acrylamide and N- (3-diethylaminopropyl) (meth) acrylamide, N, N-dimethyl-p-aminostyrene, N, N-diethyl- p-aminostyrene, dimethyl (p-vinylbenzyl) amine, diethyl (p-vinylbenzyl) amine, dimethyl (p-vinylphenethyl) amine, diethyl (p-vinylphenethyl) amine, dimethyl (p-vinylbenzyloxymethyl) Amine, dimethyl [2- (p-vinylbenzyloxy) ethyl] amine, diethyl (p-vinylbenzyloxymethyl) amine, diethyl [2- (p-
Vinylbenzyloxy) ethyl] amine, dimethyl (p
-Vinylphenethyloxymethyl) amine, dimethyl [2- (p-vinylphenethyloxy) ethyl] amine, diethyl (p-vinylphenethyloxymethyl) amine, diethyl [2- (p-vinylphenethyloxy))
Examples thereof include tertiary amino group-containing vinyl aromatic compounds such as ethyl] amine, 2-vinylpyridine, 3-vinylpyridine, and 4-vinylpyridine. Of these, dialkylaminoalkyl (meth) acrylates and tertiary amino group-containing vinyl aromatic compounds are preferable. Of these, only one kind may be used, or two or more kinds may be used in combination.

As the monomer having a carboxyl group,
Unsaturated carboxylic acids such as (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, tetraconic acid and cinnamic acid,
Contains free carboxyl groups such as monoesters of non-polymerizable polycarboxylic acids such as phthalic acid, succinic acid and adipic acid, and unsaturated compounds containing hydroxyl groups such as (meth) allyl alcohol and 2-hydroxyethyl (meth) acrylate Examples thereof include esters and salts thereof. Of these, unsaturated carboxylic acids are preferred. Of these, only one kind may be used, or two or more kinds may be used in combination.

Examples of the monomer having an alkoxysilyl group include (meth) acryloxymethyltrimethoxysilane,
(Meth) acryloxymethylmethyldimethoxysilane,
(Meth) acryloxymethyldimethylmethoxysilane,
(Meth) acryloxymethyltriethoxysilane, (meth) acryloxymethylmethyldiethoxysilane, (meth) acryloxymethyldimethylethoxysilane, (meth) acryloxymethyltripropoxysilane, (meth) acryloxymethylmethyldipropoxy Silane,
(Meth) acryloxymethyldimethylpropoxysilane, γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryloxypropylmethyldimethoxysilane, γ- (meth) acryloxypropyldimethylmethoxysilane, γ- (meth ) Acryloxypropyltriethoxysilane, γ- (meth) acryloxypropylmethyldiethoxysilane, γ- (meth) acryloxypropyldimethylethoxysilane, γ- (meth) acryloxypropyltripropoxysilane, γ- (meth) Acryloxypropylmethyldipropoxysilane, γ-
(Meth) acryloxypropyldimethylpropoxysilane, γ- (meth) acryloxypropylmethyldiphenoxysilane, γ- (meth) acryloxypropyldimethylphenoxysilane, γ- (meth) acryloxypropylmethyldibenzyloxysilane, γ -(Meth) acryloxypropyl dimethyl benzyloxy silane etc. can be mentioned. Of these, only one kind may be used, or two or more kinds may be used in combination.

Further, the partially crosslinked copolymer rubber can be obtained by copolymerizing the above various monomers with a polyfunctional unsaturated monomer. This polyfunctional unsaturated monomer is 1
It is a copolymerizable monomer having two or more polymerizable unsaturated bonds in the molecule. Examples of this monomer include polyvalent allyl compounds, polyvalent (meth) acrylate compounds, divinyl compounds, bismaleimide compounds, and dioxime compounds. Specifically, for example, triallyl cyanurate, triallyl isocyanurate, trimethylolpropane tri (meth) acrylate, N, N'-m-phenylene bismaleimide, ethylene glycol di (meth) acrylate, 1,3-butane. Diol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate,
2,2'-bis (4-methacryloyldiethoxyphenyl) propane, pentaerythritol tri (meth) acrylate, divinylbenzene, bismaleimide, N,
Examples thereof include N'-methylenebisacrylamide, p-quinonedioxime, p, p'-dibenzoylquinonedioxime and triazinethiol. Of these, only one kind may be used, or two or more kinds may be used in combination.

The content of various monomer units contained in the acrylonitrile rubber is not particularly limited as long as it is appropriately selected according to the required characteristics. However, the unsaturated nitrile monomer unit is preferably 30% by mass or more, and more preferably 40 to 70% by mass.
When the content of the unsaturated nitrile monomer unit is less than 30% by mass, it tends to be difficult to obtain sufficient mill shrinkage and vibration damping performance of the obtained rubber composition, and the obtained rubber composition is crosslinked. The hardness afterwards may be too low. Further, the conjugated diene monomer unit is preferably 70% by mass or less, and more preferably 30 to 60% by mass. Further, when the copolymerizable monomer unit having a polar group other than the nitrile group is contained, this monomer unit is preferably 10% by mass or less, more preferably 5% by mass or less.

When the monomer units contained in the acrylonitrile rubber are an unsaturated nitrile monomer unit and a conjugated diene monomer unit, the unsaturated nitrile monomer unit is 30
The content of the conjugated diene monomer unit is preferably 70% by mass or less, more preferably 40 to 70% by mass, and the conjugated diene monomer unit is more preferably 30 to 60% by mass. . Further, when the monomer unit contained in the acrylonitrile-based rubber is an unsaturated nitrile monomer unit, a conjugated diene monomer unit and a copolymerizable monomer unit having a polar group other than a nitrile group, 30% by mass or more of unsaturated nitrile monomer units, 7 conjugated diene monomer units
Less than 0% by weight, the copolymerizable monomer unit having a polar group excluding nitrile group is preferably 10% by weight or less,
Unsaturated nitrile monomer unit is 40% by mass or more and 70
It is more preferable that the content of the copolymerizable monomer unit is less than 30% by mass, the conjugated diene monomer unit is 30% by mass or more and less than 60% by mass, and the copolymerizable monomer unit having a polar group excluding the nitrile group is 5% by mass or less. However, the above contents are all based on 100% by mass of the entire acrylonitrile rubber. The molecular weight of the acrylonitrile rubber is not particularly limited, but the Mooney viscosity [ML _{1 + 4} (100 ° C.)] is 20.
It is preferable that it is ~ 200.

(2) Acrylic rubber This "acrylic rubber" is a rubber polymerized or copolymerized with at least an alkyl acrylate ester. In the case of a copolymer rubber, an alkyl vinyl ether, a copolymerizable monomer having a polar group and other monomers can be used in addition to the acrylic acid alkyl ester, and the alkyl vinyl ether is usually used. One of these may be used, or two or more may be used in combination. Furthermore, these partially crosslinked copolymer rubbers may be used.

Examples of the acrylic acid alkyl ester include ethyl acrylate, propyl acrylate, butyl acrylate and the like. Examples of the alkyl vinyl ether include chloromethyl vinyl ether and chloroethyl vinyl ether.
Further, as the copolymerizable monomer having a polar group (hereinafter, referred to as “polar group-containing monomer”), a hydroxyl group, an epoxy group, an amino group, a carboxyl group, an alkoxysilyl group, a nitrile group, etc. The monomer which has at least 1 sort (s) can be mentioned. Of these, each of the monomer having a hydroxyl group, the monomer having an epoxy group, the monomer having an amino group, the monomer having a carboxyl group, and the monomer having an alkoxysilyl group is the above (1).
Each monomer described in the column of acrylonitrile rubber can be applied. Further, as the monomer having a nitrile group, the unsaturated nitrile monomer described in the same column can be applied.

Further, as other monomers, alkoxyalkyl acrylates such as methoxymethyl acrylate, ethoxymethyl acrylate, methoxyethyl acrylate and ethoxyethyl acrylate which can improve the cold resistance of the acrylic rubber, and the like. , Ethylene and the like can also be used. Moreover, the polyfunctional unsaturated bond containing monomer which can obtain a partially crosslinked copolymer rubber by copolymerizing with each monomer can be mentioned. As the polyfunctional unsaturated bond-containing monomer, the polyfunctional unsaturated bond-containing monomer described in the section (1) Acrylonitrile rubber can be applied.

(3) Ethylene-α-olefin rubber As this "ethylene-α-olefin rubber",
Copolymer rubber of ethylene and α-olefin other than ethylene, copolymer rubber of ethylene and α-olefin other than ethylene and polar group-containing monomer, copolymer of ethylene and α-olefin other than ethylene and non-conjugated diene Polymerized rubber,
Examples thereof include copolymer rubbers of ethylene and α-olefins other than ethylene, non-conjugated dienes and polar group-containing monomers, and partially cross-linked copolymer rubbers thereof.

Examples of the α-olefin include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene and 3-. Ethyl-1-pentene, 1-
Number of carbon atoms such as octene, 1-decene, 1-undecene
There may be mentioned 12 α-olefins. Of these monomers, propylene and 1-butene are preferred. Of these, only one kind may be used, or two or more kinds may be used in combination.

As the non-conjugated diene, 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, 3,
6-dimethyl-1,7-octadiene, 4,5-dimethyl-1,7-octadiene, 5-methyl-1,8-nonadiene, dicyclopentadiene, 5-ethylidene-2-
Norbornene, 5-vinyl-2-norbornene, 2,5
-Norbornadiene and the like can be mentioned. Of these, dicyclopentadiene and 5-ethylidene-2-norbornene are preferred. Of these, only one kind may be used, or two or more kinds may be used in combination. As the polar group-containing monomer, the polar group-containing monomer described in the section of (2) acrylic rubber can be applied. Further, the partially cross-linked copolymer rubber is obtained by copolymerizing a polyfunctional unsaturated bond-containing monomer with these monomers, and the polyfunctional unsaturated bond-containing monomer has the above-mentioned (1 ) The polyfunctional unsaturated bond-containing monomer described in the column of acrylonitrile rubber can be applied.

That is, as a specific ethylene-α-olefin rubber, for example, ethylene-propylene rubber,
Ethylene-propylene-ethylidene norbornene rubber,
Ethylene-propylene-dicyclopentadiene rubber, ethylene-propylene-hexadiene rubber, ethylene-1
-Butene-dicyclopentadiene rubber, and ethylene-
1-butene-ethylidene norbornene and the like can be mentioned.

(4) Butyl rubber As the "butyl rubber", a copolymer rubber of isobutylene and isoprene, a copolymer rubber of isobutylene, isoprene and a polar group-containing monomer, and partially cross-linked copolymer rubbers thereof and the like are mentioned. Can be mentioned. As the polar group-containing monomer, the polar group-containing monomer described in the section of (2) acrylic rubber can be applied. Further, the partially cross-linked copolymer rubber is obtained by copolymerizing a polyfunctional unsaturated bond-containing monomer with these monomers, and the polyfunctional unsaturated bond-containing monomer has the above-mentioned (1 ) The polyfunctional unsaturated bond-containing monomer described in the column of acrylonitrile rubber can be applied. That is, a specific butyl rubber may include isobutylene-isoprene rubber. Also, this rubber is halogenated chloroisobutylene-
It may be isoprene rubber, bromoisobutylene-isoprene rubber or the like.

(5) Conjugated diene rubber This "conjugated diene rubber" is a rubber polymerized or copolymerized with at least a conjugated diene. When the conjugated diene rubber is a copolymer rubber, the monomer to be polymerized with the conjugated diene is not particularly limited, but examples thereof include aromatic vinyl and polar group-containing monomers. Furthermore, these partially crosslinked copolymer rubbers may be used.

Examples of the conjugated diene include 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-chloro-1,3-butadiene, 1,3-pentadiene and isoprene. . Of these monomers, 1,3-butadiene and isoprene are preferable. Of these, only one kind may be used, or two or more kinds may be used in combination.

As the aromatic vinyl, styrene,
α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4-dimethylstyrene, 4-t-butylstyrene, 5-t-butyl-2-methyl Examples thereof include styrene, monochlorostyrene, dichlorostyrene, monofluorostyrene and the like. Of these monomers, styrene is preferred. Of these, only one kind may be used, or two or more kinds may be used in combination. As the polar group-containing monomer, the polar group-containing monomer described in the section of (2) acrylic rubber can be applied. Further, the partially cross-linked copolymer rubber is obtained by copolymerizing a polyfunctional unsaturated bond-containing monomer with these monomers, and the polyfunctional unsaturated bond-containing monomer has the above-mentioned (1 ) The polyfunctional unsaturated bond-containing monomer described in the column of acrylonitrile rubber can be applied.

Examples of the conjugated diene rubber include isoprene rubber, styrene-isoprene copolymer rubber, butadiene rubber, butadiene-styrene copolymer rubber,
Examples thereof include butadiene-isoprene copolymer rubber, butadiene-styrene-isoprene copolymer rubber, and chloroprene rubber.

Examples of the above isoprene rubbers include natural rubber, isoprene rubber, trans isoprene rubber, halogenated isoprene rubber, cyclized isoprene rubber and graft isoprene rubber. Examples of the isoprene-styrene copolymer rubber include styrene-isoprene-styrene block copolymer rubber and styrene-ethylene / propylene-styrene block copolymer rubber which is a hydrogenated rubber thereof. Examples of the butadiene rubber include 1,2-polybutadiene, low cis butadiene rubber and high cis butadiene rubber.

Examples of the styrene-butadiene copolymer rubber include solution polymerization styrene-butadiene copolymer rubber and emulsion polymerization styrene-butadiene copolymer rubber, as well as styrene-butadiene-styrene block copolymer rubber and water thereof. Examples thereof include block copolymer rubbers such as styrene-ethylene / butylene-styrene block copolymer rubbers which are added rubbers, and styrene-butadiene random copolymer rubbers. Furthermore, a rubber containing two or more of these rubbers may be used. Examples of such a rubber include rubber containing isoprene-based rubber and styrene-butadiene rubber (rubber including natural rubber and styrene-butadiene-styrene rubber), rubber containing isoprene-based rubber and butadiene-based rubber, and the like. Can be mentioned. These rubbers may or may not be co-crosslinked.

The content of various monomer units contained in the conjugated diene rubber is not particularly limited as long as it is appropriately selected according to the required characteristics. However, the conjugated diene monomer unit is preferably 40 to 100% by mass, more preferably 50 to 90% by mass, and 60
It is more preferable that the content is ˜85 mass%. When the aromatic vinyl monomer unit is contained, the content of this monomer unit is preferably 60% by mass or less, more preferably 10 to 50% by mass, and 15 to 40% by mass. More preferably. Furthermore, when it contains a polar group-containing monomer unit, it is preferably 0.01 to 20 mass%.

When the monomer units contained in the conjugated diene rubber are a conjugated diene monomer unit, a conjugated diene monomer unit and an aromatic vinyl monomer unit, the conjugated diene monomer is It is preferable that the unit is 40% by mass or more and the aromatic vinyl monomer unit is 60% by mass or less,
More preferably, the conjugated diene monomer unit is 50 to 90% by mass and the aromatic vinyl monomer unit is 10 to 50% by mass, and the conjugated diene monomer unit is 60 to 75% by mass, and The aromatic vinyl monomer unit is more preferably 15 to 40% by mass. However, the above contents are all based on 100% by mass of the conjugated diene rubber.

(6) Other rubbers, etc. Other rubbers include acrylonitrile rubber, acrylic rubber, ethylene-.alpha. Listed in (1) to (5) above.
Examples of the hydrogenated rubber include olefin rubber, butyl rubber, and conjugated diene rubber, and halogenated rubber. Furthermore, epichlorohydrin-based rubber such as epichlorohydrin-ethylene oxide rubber, urethane-based rubber such as polyether urethane rubber and polyester urethane rubber, and silicone such as methyl silicone rubber, vinyl-methyl silicone rubber, phenyl-methyl silicone rubber and fluorinated silicone rubber. Examples thereof include system rubbers, fluorinated rubbers such as vinylidene fluoride rubbers and fluorinated ethylene-propylene rubbers, ethylene-vinyl acetate rubbers, and halogenated polyethylenes.

Further, a rubber type polymer containing two or more kinds of rubbers selected from the rubbers mentioned in the above (1) to (6) can be mentioned. Examples of the combination of two or more rubbers include rubbers consisting of acrylonitrile rubber and ethylene-α-olefin rubber, rubbers consisting of acrylonitrile rubber and acrylic rubber, acrylic rubber and ethylene-α-olefin rubber. Rubber consisting of and ethylene
Examples thereof include rubbers composed of α-olefin rubber and butyl rubber. However, in the case of being composed of two or more rubbers, each rubber may or may not be co-crosslinked.

Further, the rubber-based polymer of the present invention may contain a resin within the range in which rubber elasticity is not lost. This resin may or may not be co-crosslinked with the above various rubbers. As the resin, polyolefin resins such as vinyl chloride, polypropylene and polybutene, polystyrene, and the like can be used. Specific rubber-based polymers containing this resin include rubber containing acrylonitrile-based rubber and vinyl chloride resin, ethylene-α
-A rubber containing an olefin-based rubber and a polyolefin-based resin, a rubber containing a conjugated diene-based rubber and polystyrene, and the like can be given. The resin content is usually preferably 40% by mass or less, more preferably 30% by mass or less, based on 100% by mass of the rubber polymer.

(7) Method for producing rubber-based polymer The method for producing the rubber-based polymer is not particularly limited and may be any of radical polymerization method, anion polymerization method and cationic polymerization method. It is preferable to use a polymerization method suitable for the polymer. The polymerization system in these polymerization methods is not particularly limited, and may be any of emulsion polymerization, solution polymerization, suspension polymerization, bulk polymerization and the like. But,
As will be described later, the rubber polymer is preferably highly dispersed in the medium. Therefore, since a stable emulsion can be obtained at the end of the polymerization, it is more preferable to use the emulsion polymerization depending on the type of the rubber polymer.

When carrying out emulsion polymerization, a predetermined monomer is emulsified in a predetermined medium in the presence of an emulsifier, polymerization is initiated by an initiator, and after a predetermined polymerization conversion rate is reached, the polymerization is stopped. It can be used as a method of stopping the polymerization with an agent.
Examples of emulsifiers used in this emulsion polymerization method include anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric surfactants. Also,
Fluorine-based surfactants can also be used. Only one of these may be used, or two or more may be used in combination. Usually, anionic surfactants are frequently used, and for example, long-chain fatty acid salts having 10 or more carbon atoms, rosin acid salts, etc. are used. Specific examples thereof include capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, stearic acid potassium salt and sodium salt.

As the polymerization initiator, it is preferable to use a polymerization initiator suitable for each polymerization method. Examples of this polymerization initiator include radical polymerization initiators, anionic polymerization initiators, and cationic polymerization initiators. Among these, examples of the radical polymerization initiator include benzoyl peroxide, lauroyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, paramenthane hydroperoxide, di-tert-butyl peroxide and dicumyl peroxide. Organic peroxide,
Examples thereof include diazo compounds such as azobisisobutyronitrile, inorganic peroxides such as potassium persulfate, and redox catalysts represented by a combination of these peroxides and ferrous sulfate. Among these, only 1 type may be used and 2 or more types may be used together. Examples of the anionic polymerization initiator include alkali metals, alkali metal alkyls, organometallic compounds such as Grignard reagents, alkalis, amines and water. Further, as the cationic polymerization initiator, sulfuric acid, hydrogen halide, trichloroacetic acid and other proton-releasing acids, aluminum trichloride, iron trichloride, titanium tetrachloride, tin tetrachloride, and Friedel Crafts such as boron fluoride are used. A catalyst or the like can be used.

Further, in the emulsion polymerization, a chain transfer agent can be used for controlling the molecular weight. As the chain transfer agent, tert-dodecyl mercaptan,
alkyl mercaptans such as n-dodecyl mercaptan,
Carbon tetrachloride, thioglycols, diterpenes, tapinolene, γ-terpinenes and the like can be used.

When carrying out emulsion polymerization, all of the above monomers, emulsifiers, polymerization initiators, chain transfer agents, etc. may be added all at once to the reaction vessel to start the polymerization. Then
When the reaction is continued, it may be added continuously or intermittently. Further, the operating conditions such as temperature or stirring can be appropriately changed during the reaction. The polymerization system may be a continuous system or a batch system.

The polymerization can be stopped by adding a polymerization terminator at the time when a predetermined polymerization conversion rate is reached. As the polymerization terminator, amine compounds such as hydroxylamine and diethylhydroxylamine, quinone compounds such as hydroquinone and the like can be used. After termination of the polymerization, unreacted monomers are removed from the reaction system by a method such as steam distillation, if necessary, to obtain an emulsion of a rubber-type polymer that can be used in the present invention.

[2] Layered Inorganic Compound This "layered inorganic compound" is a layered inorganic compound, and is a layered silicate compound (Si-Al system, Si-Mg).
System, Si-Al-Mg system, Si-Ca system and the like. ) Etc. can be mentioned. As the layered inorganic compound,
Usually, synthetic products artificially manufactured (synthesized) using talc, etc., or processes in which synthetic compounds or natural minerals are subjected to processing such as modification by organic groups or substitution of some atoms or atomic groups Things, and further natural minerals are used.

Examples of the layered inorganic compound include various mica group minerals, various smectite group minerals, kaolinites such as kaolinite, dickite, nacrite and halloysite, and other chrysoite, pyrophyllite, talc, vermiculite and clintonite. Can be mentioned. Further, there may be mentioned those modified with an organic group or substituted with some of these atoms or atomic groups. Of these, only one type may be used, or two or more types may be used in combination.

As a method of this organic modification, all or a part of the metal ions arranged between the layers are replaced with organic onium ions, and the hydroxyl group on the surface of the particle of the layered inorganic compound is reacted with the organic compound. There are such things. Examples of the former organic onium ion include hexyl ammonium ion, dodecyl ammonium ion, octyl ammonium ion and dioctyl ammonium ion, and similar pyridinium ion, phosphonium ion, sulfonium ion and the like. Only one of these may be used, or two or more may be used in combination. Examples of the latter organic compound include silane coupling agents {vinyltrialkoxysilane, β- (3,4-epoxycyclohexyl)
Alkyltrialkoxysilane, γ-glycidoxypropylmethyldialkoxysilane, γ-aminopropyltrialkoxysilane, etc.}, epoxy group-containing compound (butyl glycidyl ether, neopentyl diglycidyl ether, epoxidized vegetable oil, propylene oxide, etc.), Examples thereof include isocyanate group-containing compounds (hexyl isocyanate, dodecyl isocyanate, etc.), isothiocyanate group-containing compounds, and the like.

These layered inorganic compounds generally have the property of intercalating a medium such as water and / or an organic solvent (particularly water) between the layers, and in particular, by intercalating these mediums. Those that swell are preferred.
The layer charge is preferably 0.2 to 1.0, more preferably 0.6 to 1.0. Furthermore,
The cation exchange capacity preferably has a cation exchange capacity of 50 to 200 meq / 100 g. Mica group minerals, smectite group minerals, vermiculite and the like are particularly preferable as those capable of exhibiting such characteristics.

Examples of the mica group minerals include muscovite, biotite, phlogopite, scaly mica, margarite and teniolite (lithium-type teniolite, sodium-type teniolite, etc.), lithium-type tetrasilicon mica and sodium-type tetrasilicon mica. Etc., and modified products obtained by modifying these with various organic groups. Further, it may be a swelling mica group mineral (swelling mica, organic modified swelling mica, etc.) or a non-swelling mica group mineral, but a swelling mica group mineral is preferable.

Of these, the swelling mica group minerals which are not organically modified can be represented by, for example, the following general formula <1>. W _{(1/3) to 1.0} Y _{3.5 to 3} (Z ₄ O ₁₀ ) L ₂ ... <1> However, W; interlayer ion (alkali metal ion or the like) Y; 6 coordination ion (Al , Alkaline earth metal ions, etc.) Z; Four coordination ions (Si, Ge, etc.) L; OH or F, etc. More specifically, Na _{0.5 to 0.8} Mg
_{2.6 to 2.75} are Si ₄ O ₁₀ F ₂ and the like. Further, the bottom spacing in the aggregated state of the mica group mineral is preferably about 1 to 2 nm, and the major axis average particle size is about 100 nm to 1
It is preferably 00 μm. As mica minerals, product name "Somasif ME-100", product name "Micromica MK-100", product name "Somasif MA"
E ", product name" Somasif MTE ", product name" Somasif ME
E "and product name" Somasif MPE ", etc., product name" DMA350 ", product name" 4C-TS ", etc. manufactured by Topy Industries, Ltd. can be used.

The smectite group minerals include montmorillonite, beidellite, nontronite, saponite,
Examples include iron saponite, hectorite, sauconite, stevensite and bentonite, and modified products obtained by modifying these with various organic groups. These smectite group minerals are, for example, Na _0.33 (Mg _{2.6 7}
Li _0.33 ) Si ₄ O ₁₀ (OH) ₂ , Na _{0.33
(Mg 2.67 Li 0 .33) Si} 4 O 10 can be expressed by a composition formula of _{F 2} or the like. Further, the bottom spacing in the aggregated state of the smectite group mineral is preferably about 1 to 2 nm, and the major axis average particle size is preferably about 100 nm to 100 μm. As smectite group minerals, product name "Lucentite SWN", product name "Lucentite SWF", product name "Lucentite S" manufactured by Coop Chemical Co., Ltd.
AN ", product name" Lucentite SPN ", etc., product name" Kunipia G ", product name" Kunipia F ", etc. manufactured by Kunimine Industry Co., Ltd., Laporte Industry (Laporte Industrial)
The product name “Laponite JS” of Ries Ltd) or the product name “Smecton SA” manufactured by Kunimine Industries Co., Ltd. can be used.

Examples of vermiculite include natural vermiculite and modified products obtained by modifying these with various organic groups. The bottom distance between these vermiculite particles in the aggregated state is preferably about 1 to 2 nm, and the major axis average particle diameter is preferably about 100 nm to 500 μm.

[3] Mixed Liquid Preparation Step (1) Mixed Liquid The above-mentioned “mixed liquid” is a liquid (particularly a dispersion liquid) containing a rubber polymer, a layered inorganic compound and a medium. The state of the rubber-based polymer and the layered inorganic compound in the mixed solution is not particularly limited, but both compounds are dispersed in the mixed solution (including an emulsified state and a suspended state) when the recovery step described later is performed.
Is preferably provided. Further, the medium constituting the mixed liquid may be any of an aqueous system, a non-aqueous system and a water / non-aqueous mixed system, but is preferably either an aqueous system or a non-aqueous system.

The method for preparing this mixed solution is not particularly limited, but it may be prepared so that both the rubber-based polymer and the layered inorganic compound are contained in the mixed solution. That is, by using each liquid (particularly a dispersion liquid) containing at least one of the rubber-based polymer and the layered inorganic compound, the rubber-based polymer and the layered inorganic compound are mixed so as to be contained. It can be prepared. Among these preparation methods, it is preferable to separately prepare and use the polymer dispersion liquid in which the rubber-type polymer is dispersed and the inorganic compound dispersion liquid in which the layered inorganic compound is dispersed.

This "polymer dispersion" is used to mean not only a liquid in which a rubber polymer is dispersed but also a dissolved solution. The medium constituting this polymer dispersion may be any of an aqueous system, a non-aqueous system and a water / non-aqueous mixed system, but is preferably an aqueous system or a non-aqueous system. Examples of the aqueous medium include water alone, a polar solvent compatible with water at an arbitrary ratio, and a mixed liquid of water and a polar solvent. Examples of the polar solvent include alcohols such as methanol, ethanol, 1-propanol and isopropanol, glycols such as ethylene glycol, propylene glycol and 1,4-butanediol, ketones such as acetone and methyl ethyl ketone, ethyl ether and diethyl ether. And ethers such as tetrahydrofuran, amide compounds such as dimethylformamide, and other solvents such as dimethyl sulfoxide and 2-pyrrolidone. Only one of these may be used, or two or more may be used in combination.

On the other hand, examples of the non-aqueous medium include aromatic compounds such as benzene, toluene and xylene, hydrocarbons such as pentane, hexane, octane and cyclohexane, water-insoluble alcohol compounds such as cyclohexanol, and tetrachloro. In addition to halogenated hydrocarbons such as methane, dichloromethane, dichloroethane, chloroform, perchloroethylene and chlorobenzene, ethyl acetate, methyl methacrylate, dioctyl phthalate, ethyl acetate, methyl cellosolve, ethyl cellosolve, cottonseed oil, castor oil, rapeseed oil, etc. Vegetable oil etc. can be mentioned. Only one of these may be used,
You may use 2 or more types together.

In preparing the polymer dispersion, each of the above-mentioned aqueous medium and non-aqueous medium is preferably selected so that the rubber-based polymer to be used is more highly dispersed. Further, it is preferable to use a latex obtained by emulsion polymerization or suspension polymerization in an aqueous system, and it is preferable to use a polymer solution in which various rubber polymers are dissolved in a non-aqueous system. In the case of an aqueous system, a finely divided rubber-based polymer can be prepared by using a surfactant or the like in an aqueous medium.

The "inorganic compound dispersion liquid" is a liquid in which the layered inorganic compound is dispersed. The medium constituting the inorganic compound dispersion may be any of the above-mentioned aqueous system, non-aqueous system and water / non-aqueous mixed system, but is preferably aqueous system or non-aqueous system. Furthermore, the inorganic compound dispersion is usually obtained by immersing the layered inorganic compound in a medium. The immersion time at this time is not particularly limited, and stirring (including heating stirring, ultrasonic stirring, etc.) can be performed.

When the polymer dispersion and the inorganic compound dispersion are mixed, the system of each dispersion may be the same or different. Therefore, examples of the mode for preparing the mixed liquid include the following modes (1) to (3). An aqueous (particularly water) polymer dispersion and an aqueous (particularly water) inorganic compound dispersion are mixed. A non-aqueous polymer dispersion and a non-aqueous inorganic compound dispersion are mixed. An aqueous (particularly water) polymer dispersion and a non-aqueous inorganic compound dispersion are mixed. Aspect of Mixing Non-Aqueous Polymer Dispersion with Aqueous (Particularly Water) Inorganic Compound Dispersion Among these aspects, or is preferable.
Further, as the non-aqueous polymer dispersion liquid in the above and above, a polymer solution obtained by solution polymerization is preferable. The layered inorganic compound contained in the non-aqueous inorganic compound dispersion liquid in the above and above is preferably organically modified. In addition, when preparing the mixed solution, stirring (including heating stirring, ultrasonic stirring, and the like) can be performed to achieve more uniform mixing.

The ratio of the rubber-based polymer and the layered inorganic compound contained in the mixed solution is not particularly limited, but 100 parts by mass of the rubber-based polymer contained in the mixed solution (hereinafter referred to as “part”).
Abbreviated), the layered inorganic compound is 1 to 15
It may be 0 part, preferably 20 to 70 parts. When the amount ratio of the layered inorganic compound exceeds 150 parts, it becomes difficult to uniformly disperse the rubber polymer and the layered inorganic compound. In addition, the viscosity of the obtained rubber composition may increase more than necessary. On the other hand, when the amount is less than 1 part, it may be difficult to sufficiently obtain the effect of containing the layered inorganic compound in the obtained rubber composition.

[4] Recovery Step The above-mentioned “recovery step” is a step of recovering the rubber composition containing the rubber-based polymer and the layered inorganic compound from the mixed solution prepared in the mixed solution preparing step. In this recovery step, it is necessary to separate the rubber composition from the mixed solution,
The method of performing this separation is not particularly limited. For example, regardless of the dispersion state of the rubber composition in the mixed liquid, filtration,
It can be collected by a method such as centrifugation and drying (whether or not heating is performed). Further, when the rubber-based polymer and the layered inorganic compound, which are the rubber composition, are respectively dispersed in the mixed liquid, it is preferable to include a co-coagulation step of co-coagulating these. That is, after co-coagulation, it can be separated, and then dried and recovered.

This "coagulation step" is a step in which both the rubber polymer and the layered inorganic compound are coagulated at the same time. The method of performing this coagulation is not particularly limited. For example, when the mixed liquid is an aqueous system, the cationic substance and the polyvalent metal salt can be directly added to the mixed liquid without preparing an aqueous electrolyte solution containing the cationic substance and the polyvalent metal salt. . Further, an electrolyte aqueous solution containing a cation-based substance, an electrolyte aqueous solution containing a polyvalent metal salt, and an electrolyte aqueous solution containing both a cation-based substance and a polyvalent metal salt, as a result, by appropriately selecting the combination, It is carried out by contacting the mixed solution with the electrolyte aqueous solution so that the cationic substance and the polyvalent metal salt (polyvalent metal ion in the electrolyte aqueous solution) can co-coagulate the rubber polymer and the layered inorganic compound. You can

This contact method is not particularly limited, but the following modes (1) to (4) can be mentioned, for example. The mixed solution is mixed with an aqueous electrolyte solution containing a cationic substance and a polyvalent metal salt. An aqueous electrolyte solution containing a cationic substance and a polyvalent metal salt is mixed with the mixed solution. An aqueous electrolyte solution containing a cationic substance and an aqueous electrolyte solution containing a polyvalent metal salt are simultaneously mixed with the mixed solution.

In addition to these contacting methods, a mixed solution and an electrolyte aqueous solution containing a polyvalent metal salt are simultaneously mixed with an electrolyte aqueous solution containing a cationic substance, or an electrolyte containing a polyvalent metal salt is used. It is also possible to simultaneously mix the mixed solution and the aqueous electrolyte solution containing the cationic substance with the aqueous solution. Further, any one of the mixed solution, the electrolyte aqueous solution containing the cationic substance, and the electrolyte aqueous solution containing the polyvalent metal salt is mixed with the other two solutions separately (whichever may be mixed first). You can also do it.

It is also possible to mix an aqueous electrolyte solution containing a cationic substance and a polyvalent metal with an aqueous electrolyte solution containing a cationic substance and a mixed solution. Furthermore, stirring (including heating stirring, ultrasonic stirring, and the like) can be performed when the mixed solution and the electrolyte aqueous solution are brought into contact with each other.

The above-mentioned "cationic substance" is a substance which can act together with a polyvalent metal salt to co-coagulate a rubber-based polymer and a layered inorganic compound, and has a hydrocarbon group and a cation which have an affinity for rubber. A substance having a group or the like can be used. Specifically, it is at least one selected from cationic polymer compounds and cationic surfactants.

Examples of the cationic polymer compound include cationic group-containing poly (meth) acrylic acid ester (co) polymer, water-soluble aniline resin, polythiourea, polyethyleneimine, polyvinylpyridines and polyamidines. it can. Of these, cationic group-containing poly (meth) acrylic acid ester (co) polymers are preferable. Of these, only one kind may be used, or two or more kinds may be used in combination. Examples of the cation group contained in the cation group-containing poly (meth) acrylic acid ester (co) polymer include a quaternary ammonium salt and / or an amino group. Examples of the main chain of this (co) polymer include a poly (meth) acrylic acid ester polymer and a (meth) acrylic acid ester- (meth) acrylamide copolymer. Only one of these may be used, or two or more may be used in combination.

As the cationic surfactant, alkylamine acetates such as coconut amine acetate and stearyl amine acetate, alkyl amine hydrochlorides such as coconut amine hydrochloride and stearyl amine hydrochloride, lauryl dimethyl amine oxide, etc. Alkylamine oxides, lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, cetyltrimethylammonium chloride, distearyldimethylammonium chloride and other alkylammonium halides, alkylbenzyldimethylammonium chloride and other alkylarylammonium halides, laurylbetaine, stearyl Examples thereof include alkyl betaines such as betaine. Only one of these may be used, or two or more may be used in combination.

The polyvalent metal salt is capable of co-coagulating the rubber-type polymer and the layered inorganic compound by acting together with the cation-based substance, and usually a cation having a valence of 2 or more in an aqueous solution. It can be generated. As such a polyvalent metal salt, an acid selected from hydrochloric acid, nitric acid, sulfuric acid and the like, and a polyvalent metal selected from aluminum, calcium, magnesium, titanium, manganese, iron, cobalt, nickel, zinc and tin Examples thereof include salts (which are polyvalent metal ions in water). That is, for example, aluminum chloride, calcium chloride, magnesium chloride, titanium chloride, manganese chloride, iron chloride, cobalt chloride, nickel chloride, zinc chloride, tin chloride, aluminum nitrate, calcium nitrate, magnesium nitrate, titanium nitrate, manganese nitrate, nitric acid Examples thereof include iron, cobalt nitrate, nickel nitrate, zinc nitrate, tin nitrate, aluminum sulfate, calcium sulfate, magnesium sulfate, titanium sulfate, manganese sulfate, iron sulfate, cobalt sulfate, nickel sulfate, zinc sulfate and tin sulfate. Only one of these may be used, or two or more may be used in combination.

Furthermore, polyaluminum chloride, sodium aluminate, ferric sulfate, chlorinated copper powder, etc., as well as permanganate compounds such as potassium permanganate and sodium permanganate, and inorganic acids were formed by condensation. Heteropoly acids such as silicomolybdic acid, phosphomolybdic acid, silicotungstic acid and phosphotungstic acid can be mentioned. Only one of these may be used, or two or more may be used in combination.

The temperature at the time of contact between the mixed solution and the aqueous electrolyte solution is not particularly limited, but is preferably 10 ° C. or higher. The pH is not particularly limited, but it is preferably 2-14. Furthermore, the temperature is set to 10 ° C. or higher and p
More preferably, H is 2-14. The amount of inorganic salts and the like remaining in the co-coagulated product obtained by this can be reduced.

Further, the co-coagulated product produced by co-coagulation is
After separation from the medium, it is usually washed and dried. The washing method and the drying method are not particularly limited, but the emulsifier, the electrolyte and the like can be removed by, for example, washing the separated co-coagulated product with water. Further, the medium can be removed by hot air drying or the like. This allows
It is possible to obtain a co-coagulated product in which the rubber-based polymer and the layered inorganic compound are uniformly dispersed.

As described above, other than the method of contacting the rubber-based polymer and the layered inorganic compound with the cation-based substance and the polyvalent metal salt to carry out the co-coagulation, other methods can be used for co-coagulation. . That is, for example, when a mixed solution is formed from a polymer solution in which a rubber polymer is dissolved and an inorganic compound dispersion liquid of a medium different from the polymer solution, one of the media is removed by a steam stripping method or the like. By doing so, the rubber-based polymer and the layered inorganic compound can be co-solidified.

[5] Rubber Composition The rubber composition of the present invention is obtained by the production method of the present invention, and contains a rubber polymer and a layered inorganic compound. Furthermore, the rubber composition obtained through the co-coagulation step usually also contains a cationic substance and a polyvalent metal salt. The mill shrinkage of the rubber composition of the present invention can be usually 15% or less, and further 10% or less. The mill shrinkage is the shrinkage after the sheet is formed with a roll or the like, and the extent of the shrinkage can be measured as a mill shrinkage ratio according to ASTM D1917-67. If the mill shrinkage is large, when formed into a thin sheet with a roll or the like, the sheet is deformed while standing, contracts in the length direction, and becomes large in the width direction and the thickness direction. For this reason, the workability is lowered, and it is difficult to obtain sufficient smoothness of the obtained sheet. On the other hand, the rubber composition of the present invention has excellent processability, excellent sheet smoothness, and less shrinkage.

When the rubber composition of the present invention is put to practical use, a crosslinking agent and a plasticizer are usually added. Further, in addition to these, a carbon black reinforcing agent, a filler, a silane coupling agent, and the like can be blended. Furthermore,
At this time, other rubber component may be blended. Other rubber components are not particularly limited, but include styrene-butadiene copolymer rubber, butadiene rubber, isoprene rubber, butadiene-isoprene copolymer rubber, butadiene-styrene-isoprene copolymer rubber, acrylic rubber, butyl rubber, natural rubber, chloroprene. Examples thereof include rubber.

As the above-mentioned cross-linking agent, sulfur-based cross-linking agents, organic peroxides and other cross-linking agents can be used. This crosslinking agent is preferably selected and used according to the type of rubber-based polymer. As the sulfur-based crosslinking agent, powdered sulfur,
Examples include sulfur white, highly dispersible sulfur, insoluble sulfur, precipitated sulfur, surface-treated sulfur, colloidal sulfur, sulfur chloride, sulfur monochloride, and sulfur dichloride. Only one of these may be used, or two or more may be used in combination. When these sulfur-based crosslinking agents are used, one or more vulcanization accelerators such as aldehyde-ammonia-based compounds, guanidine-based compounds, thiourea-based compounds, thiazole-based compounds and dithiocarbamic acid-based compounds can be used. . These vulcanization accelerators reduce the amount of the rubber-based polymer contained in the rubber composition by 10%.
When it is 0 part, it is preferably 0.5 to 15 parts, and more preferably 1 to 10 parts.

As the organic peroxide, bis (butylperoxyisopropyl) benzene, dimethylbis (butylperoxy) hexane, dicumyl peroxide, butyl peroxide, dilauroyl peroxide,
Examples thereof include diacetyl peroxide, butyl peroxybenzoate and benzoyl peroxide. Only one of these may be used, or two or more may be used in combination. When using these organic peroxides, one or more vulcanization aids such as sulfur, sulfur compounds, oxime compounds and polyfunctional monomers can be used.

Other crosslinking agents include bisphenol A, bisphenol AF, polyol crosslinking agents such as hydroquinone and pentaerythritol, alkylphenol / formaldehyde resin, melamine-formaldehyde condensate, triazine-formaldehyde condensate, octylphenol / formaldehyde resin, alkylphenol.・ Sulfide resin and hexamethoxymethyl
Resin crosslinking agent such as melamine resin, hexamethylenediamine carbamate, N, N′-1,6-hexanediamine,
Hexamethylenediamine, triethylene / tetramine,
Tetraethylene / pentamine, 4,4′-methylenebis (cyclohexylamine) carbamate, N, N′-dicinnamylidene-1,6-hexanediamine, ammonium benzoate and other polyamine crosslinking agents, zinc white, activated zinc white, surface treated zinc white , Zinc carbonate, complex zinc white, complex active zinc white, surface treated magnesium oxide, magnesium oxide, calcium hydroxide, ultrafine calcium hydroxide,
Metal oxide cross-linking agents such as lead monoxide, red lead and white lead, metal soap-based cross-linking agents such as sodium stearate, potassium stearate, sodium oleate and potassium oleate, N, N'-m-phenylenedimaleimide Examples thereof include various cross-linking agents such as maleimide-based cross-linking agents, trimercaptotriazines and dimercaptotriazines, and other triazine-based cross-linking agents. Only one of these may be used, or two or more may be used in combination.

Further, these cross-linking agents differ depending on the kind of the rubber-based polymer contained in the rubber composition and the content of the rubber-based polymer, and are not particularly limited, but for example, they are contained in the rubber composition. When the amount of the rubber-based polymer is 100 parts, 0.5 to 10 parts can be added, and further 1 to 6 parts can be added.

As the plasticizer, phthalic acid such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, butyl octyl phthalate, di- (2-ethylhexyl) phthalate, diisooctyl phthalate, diisodecyl phthalate. Esters, dimethyl adipate,
Diisobutyl adipate, di- (2-ethylhexyl)
Adipate, diisooctyl adipate, diisodecyl adipate, octyldecyl adipate, di- (2-ethylhexyl) azelate, diisooctyl azelate, diisobutyl azelate, dibutyl sebacate, di- (2-ethylhexyl) sebacate, diisooctyl seba In addition to trimellitic acid esters such as fatty acid esters such as catenate, trimellitic acid isodecyl ester, trimellitic acid octyl ester, trimellitic acid n-octyl ester, and trimellitic acid isononyl ester, di- (2- Ethylhexyl) fumarate, diethylene glycol monooleate, glyceryl monoricinolate, trilauryl phosphate, tristearyl phosphate, tri- (2-ethylhexyl) phosphate,
Examples thereof include tricresyl phosphate, epoxidized soybean oil, polyether ester and the like. Only one of these may be used, or two or more may be used in combination.
Further, the plasticizer is usually preferably added in an amount of 5 to 100 parts, and more preferably 10 to 60 parts, based on 100 parts of the rubber polymer contained in the rubber composition.

Further, examples of the carbon black reinforcing agent include SAF carbon black, ISAF carbon black, HAF carbon black, FEF carbon black, GPF carbon black, SRF carbon black, FT carbon black, MT carbon black, and acetylene carbon black. , Ketjen Black and the like. Only one of these may be used, or two or more may be used in combination.

As the above-mentioned filler, silica, heavy calcium carbonate, white powder, light calcium carbonate, ultrafine activated calcium carbonate, special calcium carbonate, basic magnesium carbonate, magnesium carbonate, aluminum hydroxide, and hydroxide are used. Magnesium, magnesium oxide, sericite, wollastonite, zeolite, zonotonite, asbestos, PMF (Processed Minera)
Fiber), sepiolite, potassium titanate,
Elestadite, gypsum fiber, glass balun, silica balun, hydrotalcite, fly ash balun, silas balun, carbon balun, alumina, barium sulfate,
Aluminum sulfate, calcium sulfate, molybdenum disulfide, etc. can be mentioned. Only one of these may be used, or two or more may be used in combination.

Further, examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy).
Silane, vinyltrichlorosilane, vinyltriacetoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β-
(3,4-Epoxycyclohexyl) ethyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltris (β-methoxyethoxy) silane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxylane, methyl Examples thereof include triethoxylane, hexamethyldisilazane, γ-anilinopropyltrimethoxysilane, N- [β- (N-vinylbenzalamino) ethyl] -γ-aminopropyltrimethoxysilane / hydrochloride. . Only one of these may be used, or two or more may be used in combination.

Of the above-mentioned various compounding agents, when the filler and the carbon black reinforcing agent are used in combination, they are originally contained when the rubber-based polymer contained in the rubber composition is 100 parts. The total amount of the layered inorganic compound, the filler additionally added and the carbon black reinforcing agent is 10 to 350.
It is preferably part, and more preferably 50 to 200 parts. When the total amount is less than 10 parts, it is difficult to obtain sufficient sheet smoothness and sufficiently high hardness, and for example, when used as a vibration damping member, the adhesiveness and vibration damping property deteriorate. There is. However, the amount ratio of the layered inorganic compound contained in the rubber composition, the filler, and the carbon black reinforcing agent is not particularly limited.

In addition to the above, an appropriate amount of a softening agent, an antiaging agent, a processing aid and the like can be added. Examples of the softening agent include petroleum-based softening agents, vegetable oil-based softening agents, and subs. Petroleum-based softeners are aromatic, naphthene-based,
Paraffin type softening agents and the like can be mentioned. Examples of the vegetable softener include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, peanut oil, and wax. Examples of the sub include black sub, white sub, candy sub, and the like. Only one of these may be used, or two or more may be used in combination. Incidentally, these softening agents may be contained in the rubber polymer in advance.

As the antiaging agent, a naphthylamine type,
Diphenylamine type, p-phenylenediamine type, quinoline type, hydroquinone derivative type, mono, bis, tris,
Polyphenol type, thiobisphenol type, hindered phenol type, phosphite type, imidazole type,
Examples thereof include nickel dithiocarbamate salt-based and phosphoric acid-based antioxidants. Only one of these may be used, or two or more may be used in combination.

As processing aids, stearic acid, oleic acid, lauric acid, dibutylammonium oleate,
Examples thereof include zinc stearate, calcium stearate, potassium stearate, sodium stearate and stearylamine. Only one of these may be used, or two or more may be used in combination.

[6] Rubber Molded Article The rubber molded article of the present invention is obtained from the rubber composition of the present invention. The method for obtaining this rubber molded article is not particularly limited,
For example, it can be manufactured as follows. That is, the rubber composition of the present invention and / or other rubber component,
Filler, carbon black reinforcing agent, softening agent, other compounding ingredients, etc. using a kneading machine such as a Banbury mixer.
Knead at a temperature of ~ 180 ° C. Then, the kneaded product is cooled, and a crosslinking agent, a crosslinking auxiliary agent, a crosslinking accelerator, and the like are further mixed therein using a Banbury mixer, a mixing roll, or the like, and molded into a predetermined shape. Then, a temperature suitable for the rubber-based polymer contained in the rubber composition, for example,
It can be obtained by crosslinking at 130 to 200 ° C.

The rubber molded article of the present invention has various excellent properties such as high rigidity and high tensile strength. Therefore, it is useful as a rubber for a vibration damper and a tire rubber, and is particularly suitable as a rubber for a restraint plate of a vibration damper and an inner liner of a tire. Further, it can be widely used in applications such as oil hoses, fuel hoses, gas hoses, brake hoses, and other hoses that require oil resistance, covers of these hoses, and industrial parts such as belts and oil seals. .

[0090]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In addition, "part" in Examples and Comparative Examples is based on mass unless otherwise specified. Further, various measurements in Examples and Comparative Examples were based on the following methods. [1] Various Evaluation Methods Evaluation methods for physical properties of the uncrosslinked rubber and the crosslinked rubber are as follows. (1) Characteristics of uncrosslinked rubber (a) Roll processability A rubber composition was processed using a 10-inch roll under the conditions of a roll temperature of 50 ° C, a rotation speed of 22/20 rpm, and a roll gap of 2 mm. Evaluated according to the following criteria. ◯: Workability is good, and work can be performed without problems. Δ: Although it can be processed, the rubber composition slightly floats from the roll, and the workability is inferior as compared with the above “◯”. X: Processing was difficult, the rubber composition did not wrap around the roll, and it was necessary to work with the rubber composition constantly with hands.

(A) Mooney viscosity; JIS K6300
Compliant with the Mooney viscosity test of L type rotor, ML _{1 + 4} (100
(° C) is measured. (C) Mill shrinkage rate: According to ASTM D1917-67, a 10-inch roll with a stamp is used, and the roll temperature is 50.
The fabric was wound around a roll under conditions of a temperature of 20 ° C., a rotation speed of 20/20 rpm, and a roll gap of 2 mm, and a sheet was taken out after 2 minutes. Calculation formula; Mill shrinkage rate = (10 inch roll circumference-
(L)) / 10 inch roll circumference × 100 (d) Sheet smoothness; visual observation of the rubber composition sheet (5
Judgment by the perfect score method). 1 point: The sheet expands and the surface is severely uneven. 2 points: The sheet is expanded and the surface is uneven. 3 points: The sheet is slightly expanded and the surface is slightly uneven. 4 points: No expansion is observed on the sheet, and the surface is slightly uneven. 5 points: No expansion is seen on the sheet, and no unevenness is felt on the surface.

(2) Crosslinked rubber properties (e) Tensile test and hardness test In accordance with JIS K6251, a No. 3 type test piece was used, and the tensile strength was measured at a measuring temperature of 23 ° C. and a pulling speed of 500 mm / min. T _B (MPa) and elongation at break: E _B (%) were measured. Hardness: H _S was measured using a type A-durometer according to JIS K6253. (F) Using a tan δ viscoelasticity spectrometer (manufactured by Iwamoto Seisakusho),
Tan δ was measured at a frequency of 10 Hz, dynamic strain / static strain = 1/2%, and 25 ° C.

[2] Preparation of polymer dispersion Reference Production Example 1 {Acrylonitrile latex (a),
NBR1} A polymerization container was charged with 200 parts of water, 4.5 parts of rosin acid soap, 65 parts of butadiene, 35 parts of acrylonitrile, and 0.3 part of t-dodecyl mercaptan. Then, the temperature of the polymerization vessel was set to 5 ° C., and 0.1 part of p-menthane hydroperoxide as a radical polymerization initiator, 0.07 part of ethylenediaminetetraacetic acid sodium salt, and ferrous sulfate heptahydrate 0.05. And 0.15 part of sodium formaldehyde sulfoxylate were added to start the polymerization, and when the conversion of polymerization reached 60%, diethylhydroxylamine was added to stop the polymerization. Then, unreacted monomers were removed by steam stripping to obtain an acrylonitrile-butadiene rubber latex (a) having a solid content concentration of 23% by mass (hereinafter, simply referred to as “acrylonitrile latex (a)”).

Thereafter, the acrylonitrile latex (a) is coagulated with calcium chloride to form crumbs,
Acrylonitrile rubber (NB
R1) was obtained. The amount of bound acrylonitrile of this rubber is 4
It was 0 mass% and the Mooney viscosity was 50.

Reference Production Example 2 {Acrylonitrile latex (b), NBR2} 200 parts of water, 4.5 parts of rosin acid soap, 30 parts of butadiene, 70 parts of acrylonitrile, and 0.2 part of t-dodecyl mercaptan were placed in a polymerization container. The department was set up. Then, the temperature of the polymerization vessel was set to 5 ° C., and as a radical polymerization initiator, p-menthane hydroperoxide 0.03 part, ethylenediamine tetrasodium acetate 0.02 part, and sulfuric acid first
0.01 parts of iron heptahydrate and 0.03 parts of sodium formaldehyde sulfoxylate are added to initiate polymerization,
When the conversion of the polymerization reached 60%, diethylhydroxylamine was added to terminate the polymerization. Then, unreacted monomers were removed by steam stripping to obtain an acrylonitrile-butadiene rubber latex (b) having a solid content concentration of 23% by mass (hereinafter, simply referred to as "acrylonitrile-based latex (b)").

Thereafter, the acrylonitrile latex (b) is coagulated with calcium chloride to form crumbs,
Acrylonitrile rubber (NB
R2) was obtained. The amount of bound acrylonitrile of this rubber is 5
It was 0 mass% and the Mooney viscosity was 50.

Reference Production Example 3 {Diene latex (c), SBR1} 200 parts of water, 4.5 parts of rosin acid soap, 72 parts of butadiene, 28 parts of styrene, and 0.3 part of t-dodecyl mercaptan were placed in a polymerization container. The department was set up. Then, the temperature of the polymerization vessel was set to 5 ° C., and 0.1 part of p-menthane hydroperoxide as a radical polymerization initiator, 0.07 part of ethylenediaminetetraacetic acid sodium salt, and ferrous sulfate heptahydrate 0.05. And 0.15 part of sodium formaldehyde sulfoxylate were added to start the polymerization, and when the conversion of polymerization reached 60%, diethylhydroxylamine was added to stop the polymerization. Then, unreacted monomer is removed by steam stripping to obtain a solid content concentration of 21
Mass% styrene-butadiene rubber latex (c)
(Hereinafter, simply referred to as "diene latex (c)").

Then, the diene latex (c) is coagulated with sulfuric acid and sodium chloride to form crumb, which is dried with a hot air dryer to obtain styrene-butadiene rubber (SBR).
1) was obtained. The bound styrene content of this rubber was 23.5% by mass, and the Mooney viscosity was 50.

Reference Production Example 4 {Acrylic latex (d), ACM1} A polymerization container was charged with 50 parts of ethyl acrylate, 30 parts of butyl acrylate, 28 parts of 2-methoxy acrylate, and 2 parts of vinyl chloroacetate. Then, 4 parts of sodium laurate, 200 parts of water, and 0.2 part of potassium persulfate were charged and polymerized at 50 ° C. for 15 to 20 hours,
When the polymerization conversion rate reached 90%, diethylhydroxylamine was added to terminate the polymerization. Then, unreacted monomers were removed by steam stripping to obtain an acrylic rubber latex (d) having a solid content concentration of 25% by mass (hereinafter, simply referred to as "acrylic latex (d)").

Thereafter, the acrylic latex (d) was coagulated with sulfuric acid and calcium chloride to form crumb, which was dried with a hot air dryer to obtain an acrylic rubber (ACM1).
The Mooney viscosity of this rubber was 50.

Reference Production Example 5 {Ethylene-propylene polymer solution (e), EP1} 1 liter of purified hexane and 8 ml of 5-ethylidene-2-norbornene were added to a polymerization vessel sufficiently replaced with nitrogen, and the temperature was raised to 20 ° C. Set. After that, while continuously supplying each monomer to the polymerization container at a rate of 0.5 normal liter / min of ethylene, 3.3 normal liter / min of propylene, and 0.5 normal liter / min of hydrogen, the container pressure was increased. It was adjusted to 4 kg / cm ² . Then, 2.5 ml of ethylaluminum sesquichloride dissolved in 3 ml of hexane and 0.25 ml of vanadium oxytrichloride dissolved in 1 ml of hexane were added to carry out polymerization for 30 minutes. During the polymerization, the temperature was kept at 30 ° C., propylene, ethylene, and hydrogen were continuously supplied at the initial flow rate, and the pressure inside the vessel was adjusted to maintain 4 kg / cm ^2, and after the completion of the polymerization, 11.8% by mass of the polymer content was added. An ethylene propylene polymer solution (e) containing was obtained.

Thereafter, the ethylene propylene polymer solution (e) was put into 2 liters of methanol to precipitate a polymer, and then the polymer was filtered and dried under reduced pressure to obtain 88 g of ethylene propylene rubber (EP1). ) Got. This rubber has a propylene content of 40.0% by weight,
The iodine value was 16 and the Mooney viscosity was 63.

[3] Production Example 1 of Rubber Composition Swellable mica (product name "Somasif M
E-100 ") and water were used to prepare a 6.25 mass% inorganic compound dispersion. 8000 g of this inorganic compound dispersion
(Inorganic compound content: 500 g) and acrylonitrile latex (a) 4348 g (solid content: 1000 g) were mixed to obtain a mixed liquid. On the other hand, 40 liters of an aqueous calcium chloride solution (CaCl ₂ : 20 g) containing 0.5% by mass of calcium chloride as a polyvalent metal salt, and a cationic surfactant as a cationic substance (trade name "coatamine 24P, manufactured by Kao Corporation". 10) aqueous solution of a surfactant containing 0.1% by mass (cationic surfactant: 1
g) was mixed with 50 g of an aqueous electrolyte solution. The mixed solution was added to the obtained aqueous electrolyte solution (temperature: 40 ° C.),
The rubber-based polymer and the layered inorganic compound were co-solidified to form crumbs. Next, this crumb was separated by filtration and then washed twice with water and dried with a hot air dryer to obtain a rubber composition (A). When this rubber composition (A) was ashed by heating at 640 ° C. for 8 hours in an electric furnace, the ash content was 33 mass%. The layered inorganic compound (mica) calculated from this ash is 50 parts with respect to 100 parts of the rubber-based polymer,
The proportion of the layered inorganic compound incorporated into the rubber composition by co-coagulation with the rubber-based polymer was 100% of the amount used.

The rubber composition (A) thus obtained was kneaded with zinc oxide and stearic acid in the composition shown in Table 1 using a Banbury mixer (manufactured by Kobe Steel). Then, the kneaded material was cooled, and further mixed with powdered sulfur and 2 by the composition shown in Table 1.
Blended vulcanization accelerators using a 10 inch roll,
It was formed into a sheet. Then, mold 15 x 15 x 0.2
cm, press-crosslink at 160 ° C. for 20 minutes, and
A crosslinked rubber sheet conforming to S was produced and subjected to various evaluations.

Example 2 A 6.25% by mass aqueous dispersion was prepared using swelling mica (product name "Somasif ME-100"). This inorganic compound dispersion 8000 g (inorganic compound content: 500 g) was mixed with acrylonitrile latex (b) 4348 g (solid content: 1000 g) to obtain a mixed solution. On the other hand, 40 liters of an aqueous calcium chloride solution containing 0.5% by mass of calcium chloride (CaCl ₂ : 20 g) and 0.1% of a cationic surfactant (trade name "coatamine 24P").
An aqueous electrolyte solution was obtained by mixing with 10 liters of an aqueous surfactant solution containing 10% by mass (cationic surfactant: 1 g). 50 liters of the obtained electrolyte aqueous solution (temperature 40 ° C.)
The mixed solution was added to and a rubber composition (B) was obtained in the same manner as in Example 1. The proportion of the layered inorganic compound (mica) incorporated in the rubber composition (B) measured in the same manner as in Example 1 was 100% of the amount used. A crosslinked rubber sheet was produced from the obtained rubber composition (B) in the same manner as in Example 1 and subjected to various evaluations.

Example 3 Laponite which is a layered inorganic compound (product name "Laponite J
S ”) was used to prepare a 6.25 mass% aqueous dispersion.
8000 g of this inorganic compound dispersion (inorganic compound content: 50
0g) and acrylonitrile latex (b) 434
8 g (solid content: 1000 g) was mixed to obtain a mixed liquid. On the other hand, 40 liters of calcium chloride aqueous solution containing 0.5% by mass of calcium chloride (CaCl ₂ : 20 g)
And a cationic surfactant (trade name "Coatamine 24
P ”) was mixed with 10 liters of an aqueous surfactant solution containing 0.1% by mass (cationic surfactant: 1 g) to obtain an aqueous electrolyte solution. The mixed solution was added to 50 liters of the obtained aqueous electrolyte solution (temperature: 40 ° C.), and a rubber composition (C) was obtained in the same manner as in Example 1. The proportion of the layered inorganic compound (Laponite) incorporated in the rubber composition (C) measured in the same manner as in Example 1 was 100% of the amount used. A crosslinked rubber sheet was prepared from the obtained rubber composition (C) in the same manner as in Example 1 and subjected to various evaluations.

Example 4 Swelling mica (product name "Somasif ME-
100 ") and an acrylonitrile latex (b) were obtained. On the other hand, 10 liters of an aqueous polymer flocculant solution containing 0.05% by mass of a cationic polymer flocculant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "HISET C-200") instead of the aqueous surfactant solution ( An aqueous electrolyte solution was obtained in the same manner as in Example 2 except that the cationic polymer flocculant: 5 g) was used. The mixed solution was added to 50 liters of the obtained aqueous electrolyte solution (temperature: 40 ° C.), and a rubber composition (D) was obtained in the same manner as in Example 1. The proportion of the layered inorganic compound (mica) incorporated in the rubber composition (D) measured in the same manner as in Example 1 was 100% of the amount used. A crosslinked rubber sheet was prepared from the obtained rubber composition (D) in the same manner as in Example 1 and subjected to various evaluations.

Example 5 A swellable mica (product name "Somasif ME-100") was used to prepare a 6.25% by mass aqueous dispersion. This inorganic compound dispersion liquid 4000 g (inorganic compound content: 250 g) was mixed with acrylonitrile latex (b) 4348 g (solid content: 1000 g) to obtain a mixed solution. On the other hand, 40 liters of an aqueous calcium chloride solution containing 0.5% by mass of calcium chloride (CaCl ₂ : 20 g) and 0.1% of a cationic surfactant (trade name "coatamine 24P").
An aqueous electrolyte solution was obtained by mixing with 10 liters of an aqueous surfactant solution containing 10% by mass (cationic surfactant: 1 g). 50 liters of the obtained electrolyte aqueous solution (temperature 40 ° C.)
The mixed liquid was added to and a rubber composition (E) was obtained in the same manner as in Example 1. The proportion of the layered inorganic compound (mica) incorporated in the rubber composition (E) measured in the same manner as in Example 1 was 100% of the amount used. A crosslinked rubber sheet was prepared from the obtained rubber composition (E) in the same manner as in Example 1 and subjected to various evaluations.

Example 6 Dispersion 8 in which 6.25% by mass of non-swelling mica (product name "Micromica MK-100") which is a layered inorganic compound was dispersed in a sealable container equipped with an aspirator.
000 g (inorganic compound content: 500 g) and acrylonitrile latex (b) 4550 g (solid content: 1047)
g) and then added and then concentrated with stirring. Then, the mixed liquid in a high-viscosity slurry state was put into a vacuum dryer and dried at 80 ° C. for 8 hours to obtain a rubber composition (F). The proportion of the layered inorganic compound (mica) incorporated in the rubber composition (F) was 100% of the amount used. A crosslinked rubber sheet was produced from the obtained rubber composition (F) in the same manner as in Example 1 and subjected to various evaluations.

Example 7 A 6.25% by mass aqueous dispersion was prepared using swelling mica (product name "Somasif ME-100"). This inorganic compound dispersion liquid 8000 g (inorganic compound content: 500 g) and diene latex (c) 4760 g (solid content: 1000)
and g) were mixed to obtain a mixed solution. On the other hand, 40 liters of calcium chloride aqueous solution containing 0.5% by mass of calcium chloride (CaCl ₂ : 20 g), and a surfactant aqueous solution containing 0.1% by mass of a cationic surfactant (trade name "coatamine 24P"). 10 liters (cationic surfactant: 1 g) were mixed to obtain an aqueous electrolyte solution. The mixed solution was added to 50 liters of the obtained aqueous electrolyte solution (temperature: 40 ° C.), and a rubber composition (H) was obtained in the same manner as in Example 1.
The ratio of the layered inorganic compound (mica) incorporated into the rubber composition (H) measured in the same manner as in Example 1 was 1 of the amount used.
It was 00%.

The obtained rubber composition (H) was kneaded with zinc oxide and stearic acid in the composition shown in Table 3 using a Banbury mixer (manufactured by Kobe Steel). Then, the kneaded material was cooled, and further mixed with powdered sulfur and 2 by the composition shown in Table 3.
Blended vulcanization accelerators using a 10 inch roll,
It was formed into a sheet. Then, mold 15 x 15 x 0.2
cm, press-crosslink at 160 ° C. for 20 minutes, and
A crosslinked rubber sheet conforming to S was produced and subjected to various evaluations.

Example 8 In a sealable container equipped with an aspirator, an aqueous dispersion containing 500 g of talc, which is a layered inorganic compound, and 4760 g of diene latex (c) (solid content: 1
000 g) and then concentrated with stirring. Then, the mixed solution in the form of a highly viscous slurry was placed in a vacuum dryer and dried at 80 ° C. for 8 hours to obtain a rubber composition (I). The proportion of the layered inorganic compound (mica) incorporated in this rubber composition (I) was 100% of the amount used. A crosslinked rubber sheet was prepared from the obtained rubber composition (I) in the same manner as in Example 7, and subjected to various evaluations.

Example 9 A 6.25% by mass aqueous dispersion was prepared using swelling mica (product name "Somasif ME-100"). 8000 g of this inorganic compound dispersion (inorganic compound content: 500 g) and 4000 g of acrylic latex (d) (solid content: 100)
0 g) was mixed to obtain a mixed solution. On the other hand, 40 liters of calcium chloride aqueous solution containing 0.5% by mass of calcium chloride (CaCl ₂ : 20 g), and a surfactant aqueous solution containing 0.1% by mass of a cationic surfactant (trade name "coatamine 24P"). 10 liters (cationic surfactant: 1 g) were mixed to obtain an aqueous electrolyte solution. The mixed solution was added to 50 liters of the obtained aqueous electrolyte solution (temperature: 40 ° C.), and a rubber composition (J) was obtained in the same manner as in Example 1. The proportion of the layered inorganic compound (mica) incorporated in this rubber composition (J) was 100% of the amount used.

The obtained rubber composition (J) was kneaded with stearic acid in the composition shown in Table 4 using a Banbury mixer (manufactured by Kobe Steel). Then, the kneaded product was cooled, and powdered sulfur, sodium stearate and potassium stearate were further compounded in the composition shown in Table 4 using a 10 inch roll, and molded into a sheet. Then, the mold 15
Using × 15 × 0.2 cm, press crosslinking at 160 ° C. for 20 minutes to produce a crosslinked rubber sheet according to JIS,
It was subjected to various evaluations.

Example 10 Solution-swellable hectorite (product name: "Lucentite SA
N ") and toluene were used to prepare a 6.25 wt% dispersion. 8000 g of this inorganic compound dispersion liquid (inorganic compound content: 500 g) and 8475 g of ethylene propylene polymer solution (e) having a polymer content concentration of 11.8 mass% (polymer content: 1000 g) were mixed to obtain a mixed liquid. Then, the obtained mixed liquid was put into water, then steam was added to separate the polymer and hexane, and the rubber-based polymer and the layered inorganic compound were co-coagulated to obtain crumb. Next, this crumb was separated by filtration and then dried with a hot air dryer to obtain a rubber composition (K). The proportion of the layered inorganic compound (hectorite) incorporated in the rubber composition (K) was 100% of the amount used.

The rubber composition (K) thus obtained was blended with the peroxide in the proportions shown in Table 5 using a 10-inch roll and molded into a sheet. Then, mold 15 × 15 × 0.2c
m, press-crosslinking for 30 minutes at 160 ° C., JIS
A crosslinked rubber sheet conforming to the above was prepared and subjected to various evaluations.

Comparative Example 1 Solid rubber (manufactured by JSR, product name "N215SL") 100
Part and swelling mica (Product name "Somasif ME-100")
50 parts were blended according to the formulation shown in Table 1 using a Banbury mixer (Kobe Steel Co., Ltd.) together with zinc oxide and stearic acid. Then, the kneaded product was cooled, and sulfur and a vulcanization accelerator were further mixed therein with a 10-inch roll to form a sheet. Then mold 15 x 15 x
Using 0.2 cm, press-crosslinking was carried out at 160 ° C. for 20 minutes to prepare a crosslinked rubber sheet according to JIS, and subjected to various evaluations.

Comparative Example 2 A crosslinked rubber sheet was prepared and subjected to various evaluations in the same manner as in Comparative Example 1 except that the mixing ratio of the layered inorganic compound was changed to 25 parts.

Comparative Example 3 The type of rubber was solid rubber (manufactured by JSR, product name "N23").
7 ”), except that the crosslinked rubber sheet was prepared and subjected to various evaluations in the same manner as in Comparative Example 1.

Comparative Example 4 In a sealable container equipped with an aspirator, an aqueous dispersion containing 500 g of silica (manufactured by Nippon Silica Industry Co., Ltd., product name "Nipseal VN3") which is a non-layered inorganic compound, and an acrylonitrile latex (b). 4,348g
(Solid content: 1000 g) was added and the mixture was concentrated with stirring. Then, the mixed liquid in a high-viscosity slurry state was put into a vacuum dryer and dried at 80 ° C. for 8 hours to obtain a rubber composition (G). The proportion of silica incorporated in this rubber composition (G) was 100% of the amount used. A crosslinked rubber sheet was prepared from the obtained rubber composition (G) in the same manner as in Example 1 and subjected to various evaluations.

Comparative Example 5 100 parts of solid rubber (manufactured by JSR, product name “1502”) and swelling mica (product name “Somasif ME-100”) 5
0 parts were blended according to the formulation shown in Table 3 and kneaded together with zinc oxide and stearic acid using a Banbury mixer (manufactured by Kobe Steel). Then, the kneaded product was cooled, and sulfur and a vulcanization accelerator were further mixed therein with a 10-inch roll to form a sheet. Then mold 15 x 15 x
Using 0.2 cm, press-crosslinking was carried out at 160 ° C. for 20 minutes to prepare a crosslinked rubber sheet according to JIS, and subjected to various evaluations.

Comparative Example 6 The acrylic rubber (AC
M1) 100 parts and swelling mica (Product name "Somasif ME
-100 ") and 50 parts with the compounding recipe shown in Table 4 were kneaded together with stearic acid using a Banbury mixer (manufactured by Kobe Steel). Then, the kneaded product was cooled, and powdered sulfur, sodium stearate and potassium stearate were further compounded in the composition shown in Table 4 using a 10 inch roll, and molded into a sheet. Then, mold 15 × 1
Using 5 × 0.2 cm, press cross-linking was performed at 160 ° C. for 20 minutes to prepare a cross-linked rubber sheet according to JIS, and subjected to various evaluations.

Comparative Example 7 100 parts of ethylene propylene rubber (EP1) obtained in Reference Production Example 5 above, and 50 parts of hectorite (product name "Lucentite SAN") which is a layered inorganic compound,
Peroxide was mixed in a ratio shown in Table 5 using a 10-inch roll, and molded into a sheet. Then mold 15x
Using 15 × 0.2 cm, press-crosslinking was performed at 160 ° C. for 30 minutes to prepare a crosslinked rubber sheet according to JIS, and subjected to various evaluations.

[3] Compounding Formulation and Evaluation of Physical Properties Tables 1 to 5 show properties of uncrosslinked rubber and properties of crosslinked rubber measured according to the compounding formulations of Examples 1 to 10 and Comparative Examples 1 to 7 and the above [1]. Shown in.

[0125]

[Table 1]

[0126]

[Table 2]

[0127]

[Table 3]

[0128]

[Table 4]

[0129]

[Table 5]

The items shown in Tables 1 to 5 are as follows. JSR N215SL; manufactured by JSR, product name "N215S
L ", acrylonitrile-butadiene rubber (48% by weight of bound acrylonitrile, Mooney viscosity 45). JSR N237; manufactured by JSR, product name "N237", acrylonitrile-butadiene rubber (bound acrylonitrile 34% by mass, Mooney viscosity 56). JSR 1502; manufactured by JSR, product name "1502", styrene-butadiene rubber (bound styrene 23.5% by mass, Mooney viscosity 56).

Mica ME; product name "Somasif ME-100" manufactured by Cope Chemical Co., Ltd. Mica; product name "Micromica MK-100" manufactured by Coop Chemical Co., Laponite; Laporte Industries
Ltd., product name "LAPONITE JS"Hectorite; Corp Chemical Co., product name "Lucentite SAN"Talc; Nippon Talc Co., product name "Simgon" Silica: Nippon Silica Industry Co., product name "Nipseal VN"
3 "

Zinc oxide; manufactured by Shodo Kagaku Kogyo Co., Ltd., product name "Zinc Hua 2 Kinds" stearic acid; manufactured by Kao, product name "Lunac S" Sodium stearate; manufactured by NOF Corporation, product name "NONSAR SN-1" stearic acid Potassium; manufactured by NOF CORPORATION, product name "NONSAR SK-1" vulcanization accelerator CZ; manufactured by Ouchi Shinko Chemical Industry Co., Ltd., product name "NOXCELLER CZ" vulcanization accelerator TET; manufactured by Ouchi Shinko Chemical Co., Ltd. TET "powder sulfur; product name" Jinhua fine powder sulfur "manufactured by Tsurumi Chemical Industry Co., Ltd. peroxide; product name" Perkadox 14 "manufactured by Kayaku Akzo Co., Ltd.
/ 40 ", 1,3-bis (t-butylperoxyisopropyl) benzene

[4] Observation of Dispersion State by Electron Microscope Photograph A thin film piece was cut out from each of the crosslinked rubber sheets obtained in Example 1 and Comparative Example 1 of [3] above, and the cut piece was 5,000 using a transmission electron microscope. A double-magnified photograph was taken, and an explanatory diagram of the obtained photograph is shown in FIGS. Also, thin film pieces were cut from each crosslinked rubber sheet obtained in Example 3,
A 25,000-fold magnified photograph was taken using a transmission electron microscope, and an explanatory diagram of the obtained photograph is shown in FIG.

[5] Effect of Example (1) Dispersibility of inorganic compound in rubber and its effect From the results of [4] above, FIG. 1 (Example 1) and FIG. 2 (Comparative Example 1) are compared. Then, as compared with FIG. 2 in which the layered inorganic compound is dispersed in the rubber by kneading, the layered inorganic compound in FIG. 1 in which the layered liquid is dispersed has a better dispersibility and is finely dispersed. You can see it. This can be understood from the fact that in FIG. 1, mica is dispersed with the major axis average particle size of about 1 μm, whereas in FIG. 2, the major axis average particle size is dispersed with about 3 μm.

Further, using the same laponite as in Example 3,
Roll kneading was performed so that the layered inorganic compound and the uncrosslinked rubber had the same ratio as in Example 3, and then a crosslinked rubber sheet was obtained in the same manner as in Example 3. A thin film piece cut out from this crosslinked rubber sheet was photographed at a magnification of 20 times with a laser scanning microscope, and an explanatory diagram based on the obtained photograph is shown in FIG. Comparing FIG. 3 (Example 3) with this FIG. 4, compared with FIG. 4 in which the layered inorganic compound is dispersed in the rubber by kneading, the layered inorganic compound is more dispersed in FIG. 3 using the dispersion liquid. It can be seen that the compound has good dispersibility and is finely dispersed. This means that, in FIG. 3, laponite is dispersed with a major axis average particle size of about 0.2 μm, whereas in FIG. 4, there are agglomerated particles of laponite with a major axis size of about 10 to 30 μm. It can be understood from that. The major axis average particle diameter is a value measured by number average.

Regarding the mill shrinkage ratio, from Table 1 and Table 2,
The mill shrinkage of Comparative Examples 1 to 3 by kneading is 35 to 55%, whereas the mill shrinkage of Examples 1 to 6 and Comparative Example 4 using the dispersion liquid is as small as 5 to 10%. I understand. Also in Table 3, the mill shrinkage ratio of Comparative Example 5 by kneading is 45%, whereas in Examples 7 and 8 using the dispersion liquid, it is as small as 5 to 9% (1/9 to 1/5). Times). Further, also in Table 4, the mill shrinkage ratio of Comparative Example 6 by kneading is 20.
%, Whereas in Example 9 using the dispersion, 5%
And small (1/4 times).

Regarding the smoothness of the sheet, from Tables 1 and 2, the smoothness of Comparative Examples 1 to 3 by kneading is 1 to 2, while the smoothing of Examples 1 to 6 and Comparative Example using the dispersion liquid. In 4 all are excellent as 5. Also in Table 3, the smoothness of Comparative Example 5 by kneading is 1, whereas in Examples 7 and 8 in which the dispersion liquid is used, both are excellent. Further, also in Table 4, the smoothness of Comparative Example 6 by kneading is 2, whereas in Example 9 using the dispersion liquid, it is excellent, being 5.

Therefore, it is understood that the dispersion of the inorganic compound in the rubber, that is, the fine dispersion of the inorganic compound in the rubber, results in a small mill shrinkage and an excellent sheet smoothness. . Comparative Example 4 has a small mill shrinkage as described above and is also excellent in sheet smoothness. However, Example 1 containing the same acrylonitrile rubber
While tan δ of ˜6 is 0.30 to 0.45, it remains small (0.1 to 0.5 times) as 0.15. It is considered that this is because Comparative Example 4 does not contain the layered inorganic compound.

(2) Effect of Examples Using Acrylonitrile Rubber From the results of Tables 1 and 2, Examples 1 to 6 are excellent in roll workability and have a small mill shrinkage of 10% or less.
Sheet smoothness is excellent at 5 points. Furthermore, the tensile strength is 1
0 to 16 MPa (15 to 16 P in Examples 2 to 4 and 6)
Ma), elongation at break as large as 480 to 550%, and Duro A hardness of 60 to 68 (Examples 2 to 4 and 6).
68) and tan δ is 0.30 to 0.
It is as large as 45 (0.40 to 0.45 in Examples 2 to 4 and 6). Also, it can be seen that all these characteristics are provided in a well-balanced manner. Therefore, it is assumed that the restraint plate has high rigidity and excellent vibration damping property. On the other hand, in Comparative Example 1, although the uncrosslinked rubber is excellent in roll processability and crosslinked rubber characteristics, the mill shrinkage is 35% and the sheet smoothness is inferior. In addition, Comparative Examples 2 and 3
Is excellent in roll processability of uncrosslinked rubber,
The mill shrinkage, sheet smoothness, tensile strength, elongation at break and hardness are inferior to those of Examples 1-6. Further, Comparative Example 4 is as described above.

(3) Effects of Examples Using Diene Rubber From the results shown in Table 3, Examples 7 and 8 are excellent in roll processability, have a small mill shrinkage of 9% or less, and have a sheet smoothness of 5
Excellent with points. That is, the workability of the uncrosslinked rubber is excellent. On the other hand, the tensile strength is 5 to 6 MPa, the elongation at break is 550 to 660%, and the Duro A hardness is 55.
˜57, and tan δ is 0.11 to 0.13, which shows that these crosslinked rubbers have well-balanced properties. On the other hand, in Comparative Example 5, although the uncrosslinked rubber is excellent in roll processability, the mill shrinkage ratio is 4
5%, which is 5 times that of Example 7 and 9 times that of Example 8, and the sheet smoothness is significantly inferior to 1 and Examples 7 and 8. In addition, in the crosslinked rubber properties, the tensile strength, the elongation at break, the hardness, and the tan δ were evaluated as Example 7.
And values above 8 have not been obtained.

(4) Effects of Examples Using Acrylic Rubber From the results shown in Table 4, Example 9 is excellent in roll processability, has a very small mill shrinkage of 5%, and has a sheet smoothness of 5 points. Are better. That is, the workability of the uncrosslinked rubber is excellent. On the other hand, the tensile strength is 9 MPa and the elongation at break is 4
50%, Duro A hardness of 62, and t
An δ is 0.30, which shows that these crosslinked rubbers have well-balanced properties. On the other hand, in Comparative Example 6, the roll workability of the uncrosslinked rubber was inferior to that in Example 9, and the mill shrinkage ratio was 20%, which was four times that of Example 9.
Further, the sheet smoothness is 2, which is inferior to that of Example 9. Also in terms of cross-linked rubber properties, tensile strength, elongation at break,
Neither hardness nor tan δ has a value exceeding that of Example 9.

(5) Effects of Examples Using Ethylene-α-Olefin Rubber From the results in Table 5, Example 10 has excellent roll processability,
The mill shrinkage rate is 5% or less, which is extremely small, and the sheet smoothness is excellent at 5 points. That is, the workability of the uncrosslinked rubber is excellent. On the other hand, the tensile strength is 7 MPa, the elongation at break is 500%, the Duro A hardness is 70, and the tan δ is 0.17, which means that these crosslinked rubbers have well-balanced properties. I understand. On the other hand, in Comparative Example 7, the uncrosslinked rubber has excellent mill shrinkage of 5% and sheet smoothness of 4 points. However, the roll processability is inferior to that of Example 10. In addition, in particular, the cross-linked rubber characteristics of Comparative Example 7 have a tensile strength (Example 1
0) (29%), elongation at break (50% of Example 10), and tan δ (41% of Example 10) are all inferior.

[0143]

According to the production method of the present invention, a rubber composition in which a rubber-based polymer and a layered inorganic compound are highly dispersed in each other can be easily obtained. Further, in a rubber composition that requires cross-linking (vulcanization), it is possible to obtain a rubber composition with less shrinkage during cross-linking, and to obtain a smooth sheet. Furthermore, it is possible to obtain a rubber composition having a sufficient reinforcing effect.

Furthermore, when a predetermined type of rubber type polymer is used, various excellent rubber characteristics can be exhibited. Further, when a predetermined type of layered inorganic compound is used, the dispersibility of the layered inorganic compound in the obtained rubber composition becomes particularly excellent. Furthermore, when at least one of a cationic polymer compound and a cationic surfactant is used as the cationic substance, a rubber composition having excellent dispersibility between the rubber polymer and the layered inorganic compound is obtained. You can

According to the rubber composition of the present invention obtained by the production method of the present invention, the rubber-based polymer and the layered inorganic compound are highly dispersed in each other. Further, in a rubber composition that requires cross-linking, there is little shrinkage during cross-linking, and a smooth sheet can be easily obtained. Further, a sufficient reinforcing effect can be obtained. According to the rubber molded product of the present invention, it is possible to exhibit excellent properties such as damping properties.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an electron micrograph of a crosslinked rubber sheet of Example 1.

FIG. 2 is an explanatory diagram of an electron micrograph of a crosslinked rubber sheet of Comparative Example 2.

FIG. 3 is an explanatory diagram of an electron micrograph of a crosslinked rubber sheet of Example 3.

FIG. 4 is an explanatory diagram of a cross-linked rubber sheet, which is a comparative product with respect to Example 3, by a laser scanning micrograph.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 23/00 C08L 23/00 33/00 33/00 F term (reference) 4F071 AA10 AA12 AA12X AA15X AA20X AA21X AA22X AA30X AA33 AA34 AA34X AB30 AH08 AH17 AH19 4J002 AC001 AC031 AC061 AC071 AC081 BB051 BB151 BB181 BG041 BN141 BP021 DJ006 DJ036 DJ046 DJ056 FA016 FB086 FB096 GJ02 GM01 GN00 GN01 GR01

Claims (10)

[Claims] 1. A mixed solution preparing step of preparing a mixed solution containing a rubber-based polymer and a layered inorganic compound, and a rubber composition containing the rubber-based polymer and the layered inorganic compound from the mixed solution. A method for producing a rubber composition, comprising a collecting step of collecting. 2. The rubber according to claim 1, wherein the mixed liquid is obtained by mixing a polymer dispersion liquid in which the rubber-based polymer is dispersed and an inorganic compound dispersion liquid in which the layered inorganic compound is dispersed. A method for producing a composition. 3. The method for producing a rubber composition according to claim 2, wherein both the polymer dispersion and the inorganic compound dispersion are water-based. 4. The method for producing a rubber composition according to claim 2, wherein the polymer dispersion and the inorganic compound dispersion are both non-aqueous and the layered inorganic compound is modified with an organic group. 5. In the recovering step, an aqueous electrolyte solution containing one or both of a cation-based substance and a polyvalent metal salt is brought into contact with the mixed solution, and the cation-based substance and the polyvalent metal salt are used to remove The method for producing a rubber composition according to claim 1, further comprising a co-coagulation step of co-coagulating the rubber-based polymer and the layered inorganic compound from a mixed liquid. 6. The rubber-based polymer is at least one selected from the group consisting of acrylonitrile-based rubber, acrylic rubber, ethylene-α-olefin-based rubber, butyl rubber, and conjugated diene-based rubber. A method for producing the rubber composition according to any one of 1. 7. The layered inorganic compound is swellable mica,
7. At least one of montmorillonite, bentonite, saponite, hectorite, organically modified swelling mica, organically modified montmorillonite, organically modified bentonite, organically modified saponite, and organically modified hectorite. The method for producing a rubber composition according to claim 1. 8. The method for producing a rubber composition according to claim 5, wherein the cationic substance is at least one of a cationic polymer compound and a cationic surfactant. . 9. A rubber composition obtained by the method for producing a rubber composition according to any one of claims 1 to 8. 10. A rubber molded product obtained by molding the rubber composition according to claim 9.