TW201817800A - Acrylic rubber and crosslinked rubber - Google Patents

Abstract

Provided are: an acrylic rubber in which the residual amount of coagulant is 10-10,000 ppm by weight or more; and a crosslinked rubber using the acrylic rubber. According to the present invention, an acrylic rubber providing a crosslinked rubber having excellent compression set resistance and water resistance; and a crosslinked rubber using the acrylic rubber can be provided.

Description

Acrylic rubber and its manufacturing method, acrylic rubber composition and rubber crosslinked product

The present invention relates to an acrylic rubber and a rubber crosslinked product, and more specifically, to an acrylic rubber which imparts a rubber crosslinked product having excellent compression set resistance and water resistance, and a rubber crosslinked product using the acrylic rubber.

Acrylic rubber is a polymer containing acrylate as a main component, and is generally known as a rubber excellent in heat resistance, oil resistance, and ozone resistance, and is widely used in automobile-related fields.

Such an acrylic rubber is generally prepared by emulsifying and polymerizing a monomer mixture constituting the acrylic rubber, and adding a coagulant to the obtained emulsified polymerization solution to agglomerate the same, and performing water-based pellets obtained by agglomeration. It is manufactured by drying (for example, refer to Patent Document 1: Japanese Patent Laid-Open No. 7-145291).

On the other hand, in recent years, automotive parts, such as seals, hoses, shock-proof materials, pipes, tapes, and dust-proof covers, have been required to have excellent heat resistance and oil resistance. Excellent compression set resistance and water resistance. However, conventional acrylic rubbers such as the acrylic rubber described in Patent Document 1 may not have sufficient water resistance, and therefore cannot meet the requirements for water resistance in recent years.

The present invention has been made in view of such circumstances, and an object thereof is to provide an acrylic rubber that imparts a rubber crosslinked product having excellent compression set resistance and water resistance, and a rubber crosslinked product using the acrylic rubber.

The present inventors have intensively studied in order to achieve the above-mentioned object, and as a result, found that the above-mentioned object can be achieved by setting the amount of the coagulant remaining in the acrylic rubber to a specific amount range, thereby completing the present invention.

That is, according to the present invention, there is provided an acrylic rubber having a residual amount of agglomerating agent of 10 ppm by weight or more and 10,000 ppm by weight or less.

In the acrylic rubber of the present invention, the residual amount of the coagulant is preferably 10 ppm by weight or more and 3,500 ppm by weight or less, and more preferably 500 ppm by weight or more and 3,500 ppm by weight or less.

In the acrylic rubber of the present invention, the coagulant is preferably a metal salt having 1 to 3 valence, and the coagulant is preferably calcium chloride, sodium chloride, magnesium sulfate, or sodium sulfate.

In the acrylic rubber of the present invention, the residual amount of the emulsifier is preferably 10 ppm by weight or more and 22,000 ppm by weight or less.

In the acrylic rubber of the present invention, the residual amount of the slip agent is preferably 0.1 to 0.4% by weight.

In the acrylic rubber of the present invention, the residual amount of the anti-aging agent is preferably 500 ppm by weight or more and 12,000 ppm by weight or less.

The acrylic rubber of the present invention preferably has an acrylic rubber content of 95% by weight or more.

In addition, according to the present invention, there is provided a method for manufacturing an acrylic rubber, which is a method for manufacturing the above-mentioned acrylic rubber, and includes the following steps: an emulsification polymerization step, which is performed by emulsion-polymerizing a monomer used to form the aforementioned acrylic rubber, thereby obtaining An emulsification polymerization solution; a coagulation step in which an agglomerating agent is added to the aforementioned emulsion polymerization solution to obtain water-containing pellets; a washing step in which the water-containing pellets are washed; and a drying step in which the water-containing pellets which have been washed are dried.

In the method for producing an acrylic rubber of the present invention, the amount of the agglomerating agent added is preferably 3 to 33 parts by weight based on 100 parts by weight of the acrylic rubber component contained in the emulsion polymerization solution.

In the method for producing an acrylic rubber of the present invention, it is preferable to further include an addition step, and the addition step is such that the aforementioned emulsion polymerization solution before coagulation contains a material selected from the group consisting of a lubricant, an anti-aging agent, and an ethylene oxide polymer. At least one.

The present invention also provides an acrylic rubber composition containing the acrylic rubber and a crosslinking agent, and a rubber crosslinked product obtained by crosslinking such an acrylic rubber composition.

According to the present invention, it is possible to provide an acrylic rubber that imparts a rubber crosslinked product having excellent compression set resistance and water resistance, and a rubber crosslinked product having excellent compression set resistance and water resistance by using such an acrylic rubber.

＜ Acrylic rubber ＞

The acrylic rubber of the present invention contains (meth) acrylic acid ester monomers [acrylic acid ester monomers and / Or methacrylate monomer. The meaning of methyl (meth) acrylate and the like described later has the same meaning] a rubber-like polymer of a unit, and the residual amount of the aggregating agent is 10 ppm by weight to 10,000 ppm by weight.

The main component of the acrylic rubber of the present invention is a (meth) acrylate monomer unit. The (meth) acrylate monomer forming the (meth) acrylate monomer unit is not particularly limited, but examples thereof include For example, an (meth) acrylic acid alkyl ester monomer, (meth) actylic acid alkoxyalkyl ester monomer, and the like.

The (meth) acrylic acid alkyl ester monomer is not particularly limited, but an ester of an alkanol having 1 to 8 carbon atoms and (meth) acrylic acid is preferred, and specifically, (meth) acrylic acid methyl ester Esters, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, (meth) N-hexyl acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like. Among these, ethyl (meth) acrylate and n-butyl (meth) acrylate are preferred. Particularly preferred are ethyl acrylate and n-butyl acrylate. These can be used alone or in combination of two or more.

The alkoxyalkyl (meth) acrylate monomer is not particularly limited, but an alkoxy alkyl alcohol having 2 to 8 carbons and an ester of (meth) acrylic acid are preferred. Specifically, Specific examples include methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-propoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, and the like. Among these, 2-ethoxyethyl (meth) acrylate and 2-methoxyethyl (meth) acrylate are preferred, and 2-ethoxyethyl acrylate and 2-methoxyethyl acrylate are particularly preferred. Esters are preferred. These can be used alone or in combination of two or more.

In the acrylic rubber of the present invention, the content of the (meth) acrylate monomer unit is usually 50 to 99.9% by weight, preferably 60 to 99.5% by weight, and most preferably 70 to 99.5% by weight. If the content of the (meth) acrylate monomer unit is too small, the weather resistance, heat resistance, and oil resistance of the obtained rubber crosslinked product may decrease. On the other hand, if the content of the (meth) acrylate monomer unit is too large, the obtained rubber crosslink may be reduced. The heat resistance of the material may be reduced.

In addition, in the acrylic rubber of the present invention, as the (meth) acrylate monomer unit, 30 to 100% by weight of the (meth) acrylate alkyl monomer unit and 70 to 0% by weight of the (meth) acrylate monomer unit are used. ) The alkoxyalkyl acrylate monomer unit is preferably formed.

The acrylic rubber used in the present invention may contain, in addition to the α, β-ethylene unsaturated carboxylic acid monomer unit, a crosslinkable monomer unit if necessary. The crosslinkable monomer forming the crosslinkable monomer unit is not particularly limited, but examples include: α, β-ethylene unsaturated carboxylic acid monomers; monomers having an epoxy group; monomers having a halogen atom Body; diene monomer; etc.

The α, β-ethylene unsaturated carboxylic acid monomer forming an α, β-ethylene unsaturated carboxylic monomer unit is not particularly limited, but examples thereof include α, β-ethylene unsaturated having 3 to 12 carbon atoms. A monocarboxylic acid, an α, β-ethylene unsaturated dicarboxylic acid having 4 to 12 carbons, and an α, β-ethylene unsaturated dicarboxylic acid having 4 to 12 carbons, and an alkanol having 1 to 8 carbons Monoesters formed. By using an α, β-ethylene unsaturated carboxylic monomer, an acrylic rubber can be made into a carboxyl-containing acrylic rubber having a carboxyl group as a crosslinking point, and thus, in the case of being a rubber crosslinked product, it can be more Improve compression resistance.

Specific examples of the α, β-ethylene unsaturated monocarboxylic acid having 3 to 12 carbon atoms include acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid, and cinnamic acid.

Specific examples of the α, β-ethylene unsaturated dicarboxylic acid having 4 to 12 carbon atoms include butenedioic acids such as fumaric acid and maleic acid; itaconic acid; citraconic acid; Chloromaleic acid; etc.

Specific examples of monoesters formed from α, β-ethylene unsaturated dicarboxylic acids having 4 to 12 carbons and alkanols having 1 to 8 carbons include monomethyl fumarate ), Monoethyl fumarate, mono-n-butyl fumarate, mono-methyl maleate, mono-ethyl maleate, mono-n-butyl maleate, etc. Monoalkylene alkylates; monocyclopentyl fumarate, fumarate, fumarate, fumarate, fumarate, fumarate, fumarate Cyclopentyl esters, maleic acid monocyclohexyl esters, maleic acid monocyclohexyl esters and the like, butadionic acid monoesters having an alicyclic structure; itaconic acid monomethyl ester, Iconic acid monoesters such as monoethyl iconate, mono-n-butyl iconate, and monocyclohexyl iconate; etc.

Among them, butadiene mono-chain alkyl ester or alicyclic monobutyric acid monoester is preferred, and fumaric acid mono-n-butyl ester, maleic acid mono-n-butyl ester, Monobutyric acid monocyclohexyl ester and maleic acid monocyclohexyl ester are more preferred, and fumaric acid mono-n-butyl ester is more preferred. These α, β-ethylene unsaturated carboxylic monomers may be used singly or in combination of two or more kinds. In addition, among the above-mentioned monomers, dicarboxylic acids also include those existing as an anhydride.

The monomer having an epoxy group is not particularly limited, but examples thereof include epoxy-containing (meth) acrylates such as glycidyl (meth) acrylate; allyl glycidyl ether; and Epoxy-containing ethers such as vinyl glycidyl ether; etc.

The monomer having a halogen atom is not particularly limited, but examples thereof include unsaturated alcohol esters of halogen-containing saturated carboxylic acids, haloalkyl (meth) acrylates, and halooxyalkyl (meth) acrylates ( haloacyloxyalkyl (meth) acrylate), (haloacetylcarbamoyloxy) alkyl (meth) acrylate, unsaturated ethers containing halogens, unsaturated ketones containing halogens, Aromatic vinyl compounds containing halogenated methyl groups, unsaturated halogenated amines containing halogens, unsaturated monomers containing halogenated ethylfluorene groups, and the like.

Specific examples of the unsaturated alcohol ester of a halogen-containing saturated carboxylic acid include vinyl chloroacetate, vinyl 2-chloropropionate, and allyl chloroacetate.

Specific examples of the haloalkyl (meth) acrylate include chloromethyl (meth) acrylate, 1-chloroethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, and (meth) ) 1,2-dichloroethyl acrylate, 2-chloropropyl (meth) acrylate, 3-chloropropyl (meth) acrylate, and 2,3-dichloropropyl (meth) acrylate.

Specific examples of the halooxyalkyl halide (meth) acrylate include 2- (chloroethylfluorenyloxy) ethyl (meth) acrylate, and 2- (chloroethanyloxy) propyl (meth) acrylate. Esters, 3- (chloroethylacetoxy) propyl (meth) acrylate, and 3- (hydroxychloroethylacetoxy) propyl (meth) acrylate.

Specific examples of the (meth) acrylic acid (halogenated ethylamidomethylformoxy) alkyl ester include 2- (chloroethylamidomethylformoxy) ethyl (meth) acrylate, and (formyl) (Meth) acrylic acid 3- (chloroethylfluorenylaminomethylmethoxy) propyl and the like.

Specific examples of the halogen-containing unsaturated ether include chloromethyl vinyl ether, 2-chloroethyl vinyl ether, 3-chloropropyl vinyl ether, 2-chloroethylallyl ether, and 3-chloropropyl allyl ether and the like.

Specific examples of the halogen-containing unsaturated ketone include 2-chloroethyl vinyl ketone, 3-chloropropyl vinyl ketone, and 2-chloroethyl allyl ketone.

Specific examples of the halogenated methyl-containing aromatic vinyl compound include p-chloromethylstyrene, m-chloromethylstyrene, o-chloromethylstyrene, and p-chloromethyl-α-methylstyrene.

Specific examples of the halogen-containing unsaturated fluorenamine include N-chloromethyl (meth) acrylamide and the like.

Specific examples of the unsaturated monomer containing a halogenated acetamyl group include 3- (hydroxychloroethylacetoxy) propylallyl ether, p-vinylbenzyl chloroacetate, and the like .

Examples of the diene monomer include a conjugated diene monomer and a non-conjugated diene monomer.

Specific examples of the conjugated diene monomer include 1,3-butadiene, isoprene, and 1,3-pentadiene.

Specific examples of the non-conjugated diene monomer include ethylidene norbornane, cyclopentadienyl, and dicyclopentadienyl (meth) acrylate. (meth) acrylate), 2-dicyclopentadienylethyl (meth) acrylate, and the like.

Even among the above-mentioned crosslinkable monomers, when an α, β-ethylene unsaturated carboxylic acid monomer is used, an acrylic rubber can be used as the acrylic rubber containing a carboxyl group. By using acrylic rubber as an acrylic rubber containing a carboxyl group, it is possible to have good oil resistance and heat resistance, and at the same time, it can improve compression resistance and permanent deformation.

In the acrylic rubber of the present invention, the content of the crosslinkable monomer unit is preferably 0.1 to 10% by weight, more preferably 0.5 to 7% by weight, and even more preferably 0.5 to 5% by weight. By setting the content of the crosslinkable monomer unit to the above range, the mechanical properties and heat resistance of the obtained rubber crosslinked product are good, and at the same time, the compression set resistance can be more appropriately improved.

The acrylic rubber of the present invention may have, in addition to the (meth) acrylate monomer unit and the crosslinkable monomer unit used as necessary, units of other monomers capable of being copolymerized therewith. Examples of such other copolymerizable monomers include aromatic vinyl monomers, α, β-ethylene unsaturated nitrile monomers, acrylamide-based monomers, and other olefin-based monomers.

Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, and divinylbenzene.

Examples of the α, β-ethylene unsaturated nitrile monomers include acrylonitrile and methacrylonitrile.

Examples of the acrylamide-based monomer include acrylamide, methacrylamide, and the like.

Examples of other olefin-based monomers include ethylene, propylene, vinyl chloride, vinylidene chloride, vinyl acetate, ethyl vinyl ether, and butyl vinyl ether.

Among other monomers capable of being copolymerized, styrene, acrylonitrile, methacrylonitrile, ethylene, and vinyl acetate are preferred, and acrylonitrile, methacrylonitrile, and ethylene are preferred.

Other copolymerizable monomers may be used alone or in combination of two or more. In the acrylic rubber of the present invention, the content of units capable of copolymerizing other monomers is usually 49.9% by weight or less, preferably 39.5% by weight or less, and most preferably 29.5% by weight or less.

In addition, in the acrylic rubber of the present invention, the residual amount of the aggregating agent is 10,000 ppm by weight or less, preferably 7,000 ppm by weight or less, more preferably 5,000 ppm by weight or less, and more preferably 3,500 ppm by weight or less. The lower limit of the residual amount is 10 ppm by weight or more. In addition, the acrylic rubber of the present invention is obtained by emulsifying and polymerizing the above-mentioned monomers. However, when an emulsion polymerization solution obtained by the emulsion polymerization is aggregated, a coagulant is usually used. Therefore, in the acrylic rubber obtained by the emulsion polymerization of the acrylic rubber according to the present invention, a coagulant is inevitably contained. On the other hand, according to the present invention, by setting the remaining amount of the coagulant in the acrylic rubber to the above-mentioned range, it is possible to make a rubber crosslinked product excellent in compression set resistance and water resistance. In addition, in the acrylic rubber of the present invention, it is preferable that the residual amount of the coagulant is small. Therefore, a method of reducing the residual amount of the coagulant in the acrylic rubber by reducing the amount of the coagulant used in the aggregation may be considered. However, since its aggregation becomes insufficient, and the recovery rate of acrylic rubber deteriorates, and multiple washing with water is required, from the viewpoint of stable production, the residual amount of coagulant in acrylic rubber is preferably 200 ppm by weight or more. It is preferably 500 ppm by weight or more. For example, the residual amount of the coagulant can be obtained by performing an elemental analysis on the acrylic rubber and measuring the content of the elements contained in the coagulant. In addition, although the method of making the remaining amount of the aggregating agent into the above-mentioned amount is not particularly limited, it can be cited as a method for reducing the remaining amount of the aggregating agent in a preferable manner in the production method of the acrylic rubber described later. Methods, methods of appropriately combining and using such aspects, and the like.

Although it does not specifically limit as an aggregating agent, For example, a 1- to trivalent metal salt is mentioned. The 1 to 3 valence metal salt is a salt containing a metal that becomes a 1 to 3 valence metal ion when dissolved in water. Although not particularly limited, examples thereof include inorganic acids selected from hydrochloric acid, nitric acid, and sulfuric acid. Or a salt of an organic acid such as acetic acid and a metal selected from the group consisting of sodium, potassium, lithium, magnesium, calcium, zinc, titanium, manganese, iron, cobalt, nickel, aluminum, and tin. In addition, hydroxides of these metals can also be used.

Specific examples of the 1 to 3 valent metal salt include sodium chloride, potassium chloride, lithium chloride, magnesium chloride, calcium chloride, zinc chloride, titanium chloride, manganese chloride, iron chloride, and chloride. Cobalt, nickel chloride, aluminum chloride, tin chloride and other metal chlorides; sodium nitrate, potassium nitrate, lithium nitrate, magnesium nitrate, calcium nitrate, zinc nitrate, titanium nitrate, manganese nitrate, iron nitrate, cobalt nitrate, nickel nitrate , Aluminum nitrate, tin nitrate and other nitrates; sodium sulfate, potassium sulfate, lithium sulfate, magnesium sulfate, calcium sulfate, zinc sulfate, titanium sulfate, manganese sulfate, iron sulfate, cobalt sulfate, nickel sulfate, aluminum sulfate, tin sulfate and other sulfuric acid Salt; etc. Among these, calcium chloride, sodium chloride, aluminum sulfate, magnesium chloride, magnesium sulfate, zinc chloride, zinc sulfate, and sodium sulfate are preferred. Among them, monovalent or divalent metal salts are preferred, calcium chloride, sodium chloride, magnesium sulfate, sodium sulfate is more preferred, and magnesium sulfate or sodium sulfate is more preferred. And, these may be used singly or in combination.

In addition, from the viewpoint that the acrylic rubber of the present invention can further improve the water resistance in the case of being used as a rubber cross-linked product, the residual amount of the emulsifier contained in the acrylic rubber is preferably 22,000 ppm by weight or less. 20,000 weight ppm or less is preferable, 18,000 weight ppm or less is more preferable, and 17,000 weight ppm or less is especially preferable. The lower limit of the residual amount of the emulsifier is not particularly limited, but it is preferably 10 ppm by weight or more, more preferably 200 ppm by weight or more, and even more preferably 500 ppm by weight or more. In addition, the acrylic rubber of the present invention is obtained by emulsifying and polymerizing the monomers described above, but an emulsifier is usually used in the emulsion polymerization. Therefore, an emulsifier is inevitably contained in the acrylic rubber obtained by emulsion polymerization as the acrylic rubber of the present invention. On the other hand, according to the present invention, by setting the residual amount of the emulsifier in the acrylic rubber to the above-mentioned range, when it is used as a rubber crosslinked product, water resistance can be further improved. In addition, for example, GPC measurement can be performed on acrylic rubber. In the measurement chart obtained by GPC measurement, the residual amount of the emulsifier can be determined from the peak area corresponding to the molecular weight of the emulsifier. In addition, the method of making the remaining amount of the emulsifier into the above amount is not particularly limited, but examples thereof include a combination of a nonionic emulsifier and an anionic emulsifier as described later, as an emulsifier. , And the method of setting the added amount to the range described later.

In addition, as described above, the acrylic rubber of the present invention contains a coagulant, but the acrylic rubber content of the acrylic rubber of the present invention is preferably 95% by weight or more, more preferably 97% by weight or more, and 98% by weight. More preferably, it is more than weight%. That is, the acrylic rubber of the present invention may also be a composition of an acrylic rubber containing an acrylic rubber component that is preferably 95% by weight or more (more preferably 97% by weight or more, and more preferably 98% by weight or more).

<Manufacturing method of acrylic rubber>

The acrylic rubber of the present invention can be produced by, for example, the following production method. That is, a method for producing an acrylic rubber having the following steps: an emulsification polymerization step in which a monomer for forming an acrylic rubber is subjected to emulsion polymerization to obtain an emulsion polymerization solution; a coagulation step in which coagulation is added to the aforementioned emulsion polymerization solution Agent to obtain water-containing pellets; a washing step in which the aforementioned water-containing pellets are washed; and a drying step in which the washed water-containing pellets are dried.

<Emulsion polymerization step>

The emulsification polymerization step in the above manufacturing method is a step of emulsion-polymerizing a monomer for forming an acrylic rubber, thereby obtaining an emulsion polymerization solution.

As the emulsification polymerization method in the emulsification polymerization step, an ordinary method may be used, and an emulsifier, a polymerization initiator, a polymerization terminator, or the like may be used in accordance with a conventional method.

The emulsifier is not particularly limited, and examples thereof include polyoxyethylene alkyl ethers such as polyoxyethylene dodecyl ether, and polyoxyethylene nonylphenyl ether. Polyoxyethylene alkylphenol ether, polyoxyethylene stearate, etc. Polyoxyethylene alkyl ester, Polyoxyethylene sorbitan alkyl ester), polyoxyethylene polyoxypropylene copolymer and other nonionic emulsifiers; myristic acid, palmitic acid, oleic acid, hypolinolenic acid and other fatty acid salts, dodecylbenzenesulfonic acid Alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, higher alcohol sulfates such as sodium lauryl sulfate, higher phosphate salts such as sodium alkyl phosphate, alkyl sulfosuccinate ) And other anionic emulsifiers; alkyltrimethylammo cationic emulsifiers such as nium chloride, dialkyl ammonium chloride, benzyl ammonium chloride; etc. These emulsifiers can be used alone or in combination of two or more. Among these non-ionic emulsifiers are polyoxyethylene polypropylene glycol, polyethylene glycol monostearate, polyoxyethylene alkyl ether, and polyoxyethylene alkyl phenol ether. Better. In addition, as the nonionic emulsifier, a weight average molecular weight of less than 10,000 is preferable, a weight average molecular weight of 500 to 8000 is more preferable, and a weight average molecular weight of 600 to 5000 is more preferable. Among these anionic emulsifiers, higher phosphate salts and higher alcohol sulfate salts are preferred.

Among these emulsifiers, nonionic emulsifiers and anionic emulsifiers are preferred, and nonionic emulsifiers and anionic emulsifiers are used in combination. By using a combination of a nonionic emulsifier and an anionic emulsifier, it is possible to effectively suppress the occurrence of fouling caused by adhesion of a polymer, etc., to a polymerization device (such as a polymerization tank) during emulsion polymerization, and to reduce simultaneously the later-mentioned The amount of coagulant used in the coagulation step can reduce the amount of coagulant in the acrylic rubber finally obtained.

In addition, by combining and using a nonionic emulsifier and an anionic emulsifier, the emulsification effect can be improved, so the amount of emulsifier itself can be reduced, and as a result, the emulsifier contained in the acrylic rubber finally obtained can be reduced. The residual amount of this can further improve the water resistance of the acrylic rubber obtained.

In the above manufacturing method, based on the total amount of the emulsifier used, the amount of the emulsifier used is preferably 0.1 to 5 parts by weight, and 0.5 to 4 parts by weight based on 100 parts by weight of the monomers used in the polymerization. More preferably, it is 1 to 3 parts by weight. When a non-ionic emulsifier and an anionic emulsifier are used in combination, the amount of the non-ionic emulsifier is more than 0 parts by weight and 4 parts by weight based on 100 parts by weight of the monomer used for polymerization. It is preferably 0.1 to 3 parts by weight, more preferably 0.5 to 2 parts by weight, more preferably 0.7 to 1.7 parts by weight, and 100 parts by weight of the monomer used for polymerization. The amount used is more than 0 parts by weight and 4 parts by weight or less, preferably 0.1 to 3 parts by weight, more preferably 0.5 to 2 parts by weight, and even more preferably 0.35 to 0.75 parts by weight. When a nonionic emulsifier and an anionic emulsifier are used in combination, the use ratio is based on the weight ratio of the nonionic emulsifier / anionic emulsifier and the ratio is 1/99 to 99/1. 10/90 to 80/20 is preferred, 25/75 to 75/25 is more preferred, 50/50 to 75/25 is even more preferred, and 65/35 to 75/25 is particularly preferred.

As the polymerization initiator, azo compounds such as azobisisobutyronitrile can be used; organic peroxides such as dicumyl hydroperoxide, cumene hydroperoxide, p-menthane hydroperoxide, and benzoylperoxide. Substances; inorganic peroxides such as sodium persulfate, potassium persulfate, hydrogen peroxide, ammonium persulfate; etc. These polymerization initiators can be used alone or in combination of two or more kinds. The amount of the polymerization initiator used is preferably 0.001 to 1.0 parts by weight based on 100 parts by weight of the monomers used for polymerization.

The organic peroxide and the inorganic peroxide as the polymerization initiator are preferably used as a redox polymerization initiator in combination with a reducing agent. The reducing agent used in combination is not particularly limited, but examples thereof include compounds containing reduced metal ions such as ferrous sulfate, sodium hexamethylenediamine tetraacetate, and copper (II) naphthenate; ascorbic acid and ascorbic acid Ascorbic acid (salt) such as sodium, potassium ascorbate; erythorbic acid (salt) such as erythorbic acid, sodium erythorbic acid, potassium erythorbic acid; saccharides; sodium sulfamate such as hydroxymethanesulfinate; sodium sulfite, potassium sulfite, and sulfurous acid Sodium bisulfite, aldehyde-sodium bisulfite, potassium bisulfite; bisulphite, sodium metabisulfite, potassium metabisulfite, sodium metabisulfite, potassium metabisulfite, etc .; Thiosulfates such as sodium thiosulfate and potassium thiosulfate; Phosphorous acid (salt) of phosphorous acid, sodium phosphite, potassium phosphite, sodium hydrogen phosphite, potassium hydrogen phosphite; pyrophosphoric acid, sodium pyrophosphite , Potassium pyrophosphite, sodium pyrophosphite, potassium pyrophosphite and other pyrophosphates (salts); sodium formaldehyde sulfoxylate and so on. These reducing agents may be used alone or in combination of two or more. The amount of the reducing agent used is preferably 0.0003 to 0.5 parts by weight with respect to 100 parts by weight of the monomers used in the polymerization.

Examples of the polymerization terminator include osmium, osmium sulfate, diethylamidine, bis (hydroxylamine) sulfonate and alkali metal salts thereof, sodium dimethyldithiocarbamate, and hydroquinone. The amount of the polymerization terminator used is not particularly limited, but it is preferably from 0.1 to 2 parts by weight based on 100 parts by weight of the monomer used for the polymerization.

The amount of water used is preferably 80 to 500 parts by weight, and more preferably 100 to 300 parts by weight with respect to 100 parts by weight of the monomers used for polymerization.

In the emulsion polymerization, if necessary, a polymerization auxiliary material such as a molecular weight adjuster, a particle size adjuster, a chelating agent, and an oxygen trapping agent can be used.

Emulsion polymerization can be performed by any of a batch method, a semi-batch method, and a continuous method, but a semi-batch method is preferred. Specifically, it is preferred that at least one of a monomer, a polymerization initiator, and a reducing agent used in the polymerization is continuously dropped to the polymerization reaction system and the polymerization reaction is performed simultaneously from the start of the polymerization reaction to an arbitrary time. For example, in a reaction system containing a polymerization initiator and a reducing agent, from the start of the polymerization reaction to an arbitrary time, the monomers used in the polymerization are continuously dropped to the polymerization reaction system and the polymerization reaction is performed simultaneously; more preferably, since The polymerization reaction is started to an arbitrary time, and the monomers, polymerization initiator, and reducing agent used for the polymerization are continuously dropped into the polymerization reaction system and the polymerization reaction is performed. By continuously dropping these and simultaneously carrying out the polymerization reaction, the emulsion polymerization can be stably performed, whereby the polymerization reaction rate can be improved. The polymerization system is usually carried out at a temperature ranging from 0 to 70 ° C, preferably from 5 to 50 ° C.

In addition, in the case where the monomers used for polymerization are continuously dropped and the polymerization reaction is performed simultaneously, it is preferable that the monomers used for polymerization are mixed with an emulsifier and water to form a monomer emulsion, and the monomer emulsion is used as a monomer emulsion. The state of the body emulsion is continuously dropped. The method for preparing the monomer emulsion is not particularly limited, and examples thereof include using a homomixer or a disk turbine to stir the entire amount of the monomers used in the polymerization and the total amount of the emulsifier. And how to stir water. The amount of water used in the monomer emulsion is preferably 10 to 70 parts by weight, and more preferably 20 to 50 parts by weight, with respect to 100 parts by weight of the monomer used for polymerization.

In addition, in the case where the monomer, the polymerization initiator, and the reducing agent used for the polymerization are continuously dropped to the polymerization reaction system and the polymerization reaction is performed simultaneously from the start of the polymerization reaction to an arbitrary time, each of these can be used It may be dropped into the polymerization system by another dropping device, or at least a polymerization initiator and a reducing agent may be mixed in advance, and if necessary, it may be dropped into the polymerization system from the same dropping device in the state of an aqueous solution. After the dropping is completed, in order to further increase the polymerization reaction rate, the reaction may be continued for an arbitrary time.

＜ Coagulation step ＞

In the above-mentioned manufacturing method, the agglomeration step is a step of adding a coagulant to the emulsion polymerization solution obtained by the above-mentioned emulsion polymerization step, thereby obtaining water-containing pellets.

Although it does not specifically limit as an aggregating agent, For example, the said 1- to 3-valent metal salt can be used suitably. From the viewpoint that the remaining amount of the aggregating agent in the finally obtained acrylic rubber is in the above range, the amount of the aggregating agent is 1 to 100 parts by weight relative to 100 parts by weight of the acrylic rubber component in the emulsion polymerization solution. Preferably, it is 2 to 40 parts by weight, more preferably 3 to 20 parts by weight, and particularly preferably 3 to 12 parts by weight. If the coagulant is too small, the coagulation becomes insufficient, and the yield of the acrylic rubber is deteriorated. On the other hand, if the coagulant is too large, the residual amount of the coagulant in the finally obtained acrylic rubber becomes excessive, and the water resistance is deteriorated.

The aggregation temperature is not particularly limited, but is preferably 50 to 90 ° C, and more preferably 60 to 80 ° C.

In addition, when manufacturing the acrylic rubber of the present invention, it is preferable to blend a part of the blending agent in the blending agent of the acrylic rubber in advance in the emulsified polymerization solution before the flocculating agent is added to cause the aggregation, specifically, Specifically, at least any one of an anti-aging agent, a lubricant, and an ethylene oxide-based polymer is blended in advance. That is, it is preferable that at least any one of an anti-aging agent, a slip agent, and an ethylene oxide-based polymer is in a state of being blended in an emulsion polymerization solution, and the emulsion polymerization solution which has been blended with these is coagulated. .

In particular, by blending an anti-aging agent in advance into the emulsified polymerization solution before coagulation, it is possible to effectively suppress deterioration of the acrylic rubber due to heat during drying in the drying step described later. Specifically, it can effectively suppress the decrease in Mooney viscosity caused by the deterioration caused by heating during drying. Furthermore, in the case of being used as a rubber crosslinked product, it can effectively improve the normal tensile strength and Elongation at break etc. In addition, in the state of the emulsion polymerization solution, the anti-aging agent can be appropriately dispersed by blending the anti-aging agent. Therefore, even when the amount of the anti-aging agent is reduced, the addition of the anti-aging agent can be fully exerted. effect. Specifically, with respect to 100 parts by weight of the acrylic rubber component in the emulsified polymerization solution, even if the blending amount of the anti-aging agent is set to be preferably 0.1 to 2 parts by weight and 0.2 to 1.2 parts by weight is more preferred. The blending amount can also give full play to its added effect. In addition, even in the case where the anti-aging agent is previously blended into the emulsified polymerization solution before the aggregation, the previously-mixed anti-aging agent is not substantially removed in the subsequent aggregation, washing, and drying, etc. When it is blended in the emulsion polymerization solution in advance, the effect of its addition can be fully exhibited.

The anti-aging agent is not particularly limited, but examples thereof include 4-methyl-2,6-bis-tertiary butylphenol, 2,6-bis-tertiary butylphenol, butylhydroxymethoxybenzene, 2,6- Bis-tertiary butyl-α-dimethylamino-p-cresol, 3- (3,5-bis-tertiary butyl-4-hydroxyphenyl) propanoic acid octadecyl ester (octadecyl-3- (3,5 -di-t-butyl-4-hydroxyphenyl) propionate), styrenated phenol, 2,2'-methylenebis (6-α-methyl-benzyl-p-cresol), 4,4'-methylene Bis (2,6-bis-tertiary butylphenol), 2,2'-methylenebis (4-methyl-6-tertiary butylphenol), 3- (3,5-bistertiary butyl-4- Butyl reaction of stearyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, alkylated bisphenol, p-cresol and dicyclopentadiene Products such as sulfur-free phenolic anti-aging agents; 2,4-bis [(octylthio) methyl] -6-methylphenol, 2,2'-thiobis- (4-methyl-6 -Tertiary butyl phenol), 4,4'-thiobis- (6-tertiary butyl o-cresol), 2,6-bis tertiary butyl-4- (4,6-bis (octylthio) -1,3,5-tris &#134116; -2-ylamino) phenol and other thiophenol-based anti-aging agents; tris (nonylphenyl) phosphite, diphenylisode Phosphite-based anti-aging agents such as cyl phosphite, tetraphenyl dipropylene glycol diphosphite; thioester-based anti-aging agents such as dilauryl thiodipropionate; phenyl-α-naphthalene Amine, phenyl-β-naphthylamine, p- (p-toluenesulfonamide) diphenylamine, 4,4 '-(α, α-dimethylbenzyl) diphenylamine, N, N-diphenylterephthalidine Amines, N-isopropyl-N'-phenyl-p-phenylenediamine, butyraldehyde-aniline condensates, and other amine-based anti-aging agents; 2-mercapto-benzimidazole and other imidazole-based anti-aging agents; 2,2,4 -Trimethyl-6-ethoxy- 1,2-dihydroquinoline and other quinoline anti-aging agents; 2,5-di- (tertiary pentyl) hydroquinone and other hydroquinone anti-aging agents; etc. These anti-aging agents may be used alone or in combination of two or more.

In addition, by blending the lubricant into the emulsified polymerization solution before aggregation, the viscosity of the finally obtained acrylic rubber can be reduced. When mixing with various admixtures using a mixing device such as a roller, it is possible to better suppress Adhesion of mixing devices such as rollers can improve productivity. That is, although a method of adding a slip agent when mixing various admixtures into acrylic rubber using a mixing device such as a roll may be considered, in this method, the dispersion of the slip agent is performed at an early stage of the mixing using the roll. Insufficient, so the sticking to the roller will occur. As a result, the mixing time of the roller will be longer. On the other hand, by blending the lubricant in advance to the emulsified polymerization solution before coagulation, The initial stage of mixing appropriately prevents sticking to the roller, so the mixing time using the roller can be shortened, and as a result, productivity can be improved. In addition, by blending the lubricant in the state of the emulsified polymerization solution, the lubricant can be appropriately dispersed. Therefore, even when the blending amount of the lubricant is reduced, the additive effect can be fully exhibited. Specifically, with respect to 100 parts by weight of the acrylic rubber component in the emulsion polymerization solution, even if the blending amount of the lubricant is set to be preferably 0.1 to 2 parts by weight, and more preferably 0.2 to 1 part by weight, The amount can also fully exert its addition effect. In addition, even in the case where the lubricant is previously blended into the emulsified polymerization solution before aggregation, the previously blended lubricant is not substantially removed during subsequent aggregation, washing, drying, etc., so even if When it is blended in the emulsion polymerization solution in advance, the effect of its addition can be fully exhibited.

The lubricant is not particularly limited, but examples thereof include polyglyceryl fatty acid ester (polyglyceryl fatty acid ester), phosphate ester, fatty acid ester, stearylamine, and higher fatty acid.

Furthermore, by mixing the ethylene oxide-based polymer in the emulsified polymerization solution before the aggregation, the cohesiveness of the emulsified polymerization solution can be improved, thereby reducing the amount of agglomeration in the agglomeration step, and thus reducing the final yield. Residue in acrylic rubber; and in the case of a rubber cross-linked product, it can further improve compression resistance and water resistance. The ethylene oxide polymer is not particularly limited as long as it is a polymer having a polyethylene oxide structure as a main chain structure, but examples thereof include polyethylene oxide, polypropylene oxide, and ethylene oxide / propylene oxide copolymer. Etc. Among them, polyethylene oxide is preferred. The blending amount of the ethylene oxide-based polymer is preferably 0.01 to 1 part by weight, and more preferably 0.1 to 0.5 part by weight based on 100 parts by weight of the acrylic rubber component in the emulsion polymerization solution. The weight average molecular weight of the ethylene oxide-based polymer is preferably 10,000 to 1 million, more preferably 10,000 to 200,000, and even more preferably 20,000 to 120,000.

In addition, in the case where an anti-aging agent, a slip agent, and an ethylene oxide-based polymer are added to the emulsion polymerization solution before aggregation, the order of addition is not particularly limited as long as it is appropriately selected.

In addition, even in the case where such an anti-aging agent, a lubricant, and / or an ethylene oxide-based polymer are previously blended into the emulsified polymerization solution before the aggregation, the aggregation is added to the emulsified polymerization solution under the same conditions as described above. Agent and coagulation operation can also obtain water-containing pellets.

＜ Cleaning steps ＞

The washing step in the manufacturing method is a step of washing the water-containing pellets obtained in the agglomeration step.

The washing method is not particularly limited, but a method of washing with water by using water as a washing liquid and mixing the water-containing pellets with the added water is mentioned. The temperature during water washing is not particularly limited, but is preferably 5 to 60 ° C, more preferably 10 to 50 ° C, and a mixing time of 1 to 60 minutes, and more preferably 2 to 30 minutes.

In addition, the amount of water added to the water-containing pellets during water washing is not particularly limited, but from the viewpoint of effectively reducing the residual amount of the coagulant in the acrylic rubber finally obtained, it is relative to the amount contained in the water-containing pellets. The solid content (mainly an acrylic rubber component) is 100 parts by weight, and the amount of water per one wash is preferably 50 to 9,800 parts by weight, and more preferably 300 to 1,800 parts by weight.

The number of times of water washing is not particularly limited, and may be one time, but from the viewpoint of reducing the remaining amount of the coagulant in the acrylic rubber finally obtained, it is preferably 2 to 10 times, and more preferably 3 to 8 times. In addition, from the viewpoint of reducing the residual amount of the flocculant in the finally obtained acrylic rubber, although the number of times of washing with water is preferred, the effect of removing the flocculant is small even if cleaning is performed beyond the above range. Since the effect of decreasing productivity due to an increase in the number of steps increases, the number of water washings is preferably set to the above range.

Further, in the present invention, acid washing using an acid as a cleaning solution may be performed after water washing. By performing acid cleaning, in the case of being used as a rubber cross-linked product, compression resistance can be further improved. In the case where acrylic rubber is a carboxyl-containing acrylic rubber having a carboxyl group, compression resistance caused by the acid cleaning The effect of improving the permanent deformability is particularly great. The acid used for the acid cleaning is not particularly limited, and sulfuric acid, hydrochloric acid, phosphoric acid, and the like can be used without limitation. In addition, in the acid cleaning, when the acid is added to the water-containing pellets, it is preferably added in the state of an aqueous solution, and is preferably added in the state of an aqueous solution of pH = 6 or less, and more preferably pH = 4 or less. Below pH = 3 is even better. The method of acid cleaning is not particularly limited, and examples thereof include a method of mixing water-containing pellets with an aqueous solution of an acid to be added.

The temperature during acid cleaning is not particularly limited, but is preferably 5 to 60 ° C, more preferably 10 to 50 ° C, and a mixing time of 1 to 60 minutes, and more preferably 2 to 30 minutes. The pH of the acid-washing washing water is not particularly limited, but is preferably pH = 6 or less, more preferably pH = 4 or less, and even more preferably pH = 3 or less. The pH of the washing water for acid washing can be determined, for example, by measuring the pH of water contained in the water-containing pellets after the acid washing.

After acid washing, it is preferable to perform water washing again, and the conditions for water washing may be the same as those described above.

＜ Drying step ＞

In the above manufacturing method, the drying step is a step of drying the water-containing pellets that have been washed in the washing step.

The drying method in the drying step is not particularly limited, but drying can be performed using, for example, a screw-type extruder, a kneading-type dryer, an expander dryer, a hot-air dryer, or a reduced-pressure dryer. . Also, a combination of these drying methods can be used. Furthermore, before drying in the drying step, if necessary, the water-containing pellets may be subjected to a sieve such as a rotary sieve, a vibrating sieve, a centrifugal dehydrator, and the like.

For example, the drying temperature in the drying step is not particularly limited, and it depends on the dryer used for drying, but in the case of using a hot air dryer, for example, the drying temperature is preferably set to 80 to 200 ° C. It is preferable to set it to 100 to 170 ° C.

According to the manufacturing method of this invention, the acrylic rubber of this invention can be obtained as mentioned above.

The acrylic viscosity of the acrylic rubber of the present invention (ML1 + 4, 100 ° C) (polymer Mooney) is preferably 10 to 80, more preferably 20 to 70, and 25 ~ 60 is more preferable.

In the acrylic rubber of the present invention, the residual amount of the lubricant contained in the acrylic rubber is preferably 0.1 to 0.4% by weight, more preferably 0.15 to 0.3% by weight, and even more preferably 0.2 to 0.3% by weight. By setting the residual amount of the lubricant in the above range, the occurrence of bleeding can be suppressed, and at the same time, the workability and roll processability of the acrylic rubber during drying can be more effectively improved. The residual amount of the lubricant can be determined by dissolving acrylic rubber in tetrahydrofuran, using tetrahydrofuran as a developing solvent, and performing GPC measurement. Specifically, from the graph obtained by GPC measurement, the integral 値 of the peak corresponding to the molecular weight of the lubricant is obtained, and this integral 値 is compared with the integral 値 of the peak of the acrylic rubber. Corresponding molecular weight is used to determine the weight ratio, whereby the lubricant content can be determined.

Furthermore, the acrylic rubber of the present invention preferably has a residual amount of an anti-aging agent contained in the acrylic rubber of 500 ppm by weight or more, more preferably 1,000 ppm by weight or more, and more preferably 2,000 ppm by weight or more. The upper limit of the content of the anti-aging agent is not particularly limited, but it is preferably 12,000 ppm by weight or less. By setting the residual amount of the anti-aging agent to the above-mentioned range, it is possible to more appropriately prevent the occurrence of deterioration due to drying, thereby further improving the tensile strength of the rubber crosslinked material. In addition, the residual amount of the anti-aging agent can be obtained, for example, by performing GPC measurement on acrylic rubber, and from the peak area corresponding to the molecular weight of the anti-aging agent in the measurement chart obtained by GPC measurement.

＜ Acrylic rubber composition ＞

The acrylic rubber composition of the present invention is obtained by blending a crosslinking agent with the acrylic rubber of the present invention.

The cross-linking agent is not particularly limited, but polyvalent amine compounds such as diamine compounds and their carbonates; sulfur; sulfur donors; tri &#134116; thiol compounds; polyvalent epoxy compounds; organic carboxylic acids can be used Ammonium acid salts; organic peroxides; metal dithiamine formate; polycarboxylic acids; quaternary onium salts; imidazole compounds; isocyanuric compounds; organic peroxides; and other conventionally known crosslinking agents. These crosslinking agents may be used singly or in combination of two or more kinds. The cross-linking agent is preferably appropriately selected depending on the type of the cross-linkable monomer unit.

Among these, in the case where the acrylic rubber of the present invention has an α, β-ethylene unsaturated carboxylic monomer unit as a crosslinkable monomer unit, a polyvalent amine compound and a carbonate thereof are used as the crosslink Agent is better.

The polyvalent amine compound and its carbonate are not particularly limited, but a polyvalent amine compound having 4 to 30 carbon atoms and a carbonate thereof are preferred. Examples of such a polyvalent amine compound and its carbonate include an aliphatic polyvalent amine compound, its carbonate, and an aromatic polyvalent amine compound.

The aliphatic polyvalent amine compound and its carbonate are not particularly limited, but examples thereof include hexamethylenediamine, hexamethylenediamine carbamate, and N, N ' -N, N'-dicinnamylidene-1,6-hexanediamine, etc. Among these, hexamethylene diamine carbamate is preferred.

The aromatic polyvalent amine compound is not particularly limited, but examples thereof include 4,4'-methylenediphenylamine, p-phenylenediamine, m-phenylenediamine, and 4,4'-diaminodiphenyl. Ether, 3,4'-diaminodiphenyl ether, 4,4 '-(m-phenylenediisopropylidene) dianiline, 4,4 '-(P-phenylene diisopropylidene) diphenylamine, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane (2,2'-bis [4- (4 -aminophenoxy) phenyl] propane), 4,4'-diaminobenzylamine benzene, 4,4'-bis (4-aminophenoxy) biphenyl, m-xylylenediamine, p-xylenexylene Amines, and 1,3,5-phenyltriamine. Among these, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane is preferred.

The content of the cross-linking agent in the acrylic rubber composition of the present invention is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, and 0.2 to 4 parts by weight with respect to 100 parts by weight of the acrylic rubber. good. By setting the content of the cross-linking agent to the above range, the rubber elasticity can be made sufficient and at the same time, the mechanical strength as a rubber cross-linked product can be excellent.

The acrylic rubber composition of the present invention preferably further contains a crosslinking accelerator. The cross-linking accelerator is not particularly limited, but the acrylic rubber of the present invention has a carboxyl group as a cross-linkable group, and when the cross-linking agent is a polyvalent amine compound or a carbonate thereof, guanidine may be used. Compounds, diazabicyclic olefin compounds, imidazole compounds, quaternary onium salts, tertiary phosphine compounds, aliphatic monovalent secondary amine compounds, aliphatic monovalent tertiary amine compounds, and the like. Among these, a guanidine compound, a diazabicyclic olefin compound, and an aliphatic monovalent secondary amine compound are preferable, and a guanidine compound is particularly preferable. These basic crosslinking accelerators may be used singly or in combination of two or more kinds.

Specific examples of the guanidine compound include 1,3-di-o-tolylguanidine, 1,3-diphenylguanidine, and the like. Specific examples of the diazabicyclic olefin compound include 1,8-diazabicyclo [5.4.0] undec-7-ene and 1,5-diazabicyclo [4.3.0] non-5-ene Wait. Specific examples of the imidazole compound include 2-methylimidazole and 2-phenylimidazole. Specific examples of the quaternary onium salt include tetra-n-butylammonium bromide, octadecyltri-n-butylammonium bromide, and the like. Specific examples of the tertiary phosphine compound include triphenylphosphine, tri-p-toluenephosphine, and the like.

An aliphatic monovalent secondary amine compound is a compound in which two hydrogen atoms of ammonia are replaced by an aliphatic hydrocarbon group. The aliphatic hydrocarbon group substituted with a hydrogen atom is preferably one having 1 to 30 carbon atoms. Specific examples of the aliphatic monovalent secondary amine compound include dimethylamine, diethylamine, dipropylamine, diallylamine, diisopropylamine, di-n-butylamine, bis-tertiary butylamine, and bis-secondary butylamine. (Di-sec-butylamine), dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, diundecylamine, dodecylamine, ditridecylamine, ditetradecylamine , Dipentadecylamine, dihexadecylamine, di-2-ethylhexylamine, and dioctadecylamine.

An aliphatic monovalent tertiary amine compound is a compound in which all three hydrogen atoms of ammonia are replaced with an aliphatic hydrocarbon group. The aliphatic hydrocarbon group substituted with a hydrogen atom is preferably one having 1 to 30 carbon atoms. Specific examples of the aliphatic monovalent tertiary amine compound include trimethylamine, triethylamine, tripropylamine, triallylamine, triisopropylamine, tri-n-butylamine, tris (tertiary butyl) amine, and tris (di) Butyl) amine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, tri (undecyl) amine, and tris (dodecyl) amine.

In the acrylic rubber composition of the present invention, the content of the crosslinking accelerator is preferably 0.1 to 10 parts by weight relative to 100 parts by weight of the acrylic rubber, more preferably 0.5 to 7.5 parts by weight, and 1 to 5 parts by weight. Extraordinary. By setting the content of the crosslinking accelerator to the above range, the tensile strength and compression set resistance of the obtained rubber crosslinked product can be further improved.

In addition, the acrylic rubber composition of the present invention may be blended with admixtures generally used in the field of rubber processing in addition to the above-mentioned components. Examples of such admixtures include: reinforcing fillers such as silica or carbon black; non-reinforcing fillers such as calcium carbonate or clay; anti-aging agents; light stabilizers; anti-scorching agents; plasticizers; processing aids Agents; adhesives; lubricants; lubricants; flame retardants; antifungal agents; antistatic agents; colorants; cross-linking retarders; etc. The blending amount of these blending agents is not particularly limited as long as it does not interfere with the purpose and effect of the present invention, and an amount corresponding to the blending purpose may be appropriately blended.

Furthermore, in the acrylic rubber composition of the present invention, rubbers, elastomers, resins, and the like other than the above-mentioned acrylic rubber of the present invention may be further blended so long as the effects of the present invention are not impaired. For example, acrylic rubber other than the acrylic rubber of the present invention, natural rubber, polybutadiene rubber, polyisoprene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and silicone can be blended. Rubber other than acrylic rubber such as rubber, fluororubber; olefin elastomer, styrene elastomer, vinyl chloride elastomer, polyester elastomer, polyamide elastomer, polyurethane elastomer, polysiloxane Elastomers such as alkane-based elastomers; polyolefin resins, polystyrene resins, polyacrylic resins, polyphenylene ether resins, polyester resins, polycarbonate resins, polyamide resins, vinyl chloride resins Resins such as base resins, fluororesins; etc. In addition, with respect to 100 parts by weight of the acrylic rubber, the total blending amount of the rubber, elastomer and resin other than the acrylic rubber of the present invention is preferably 50 parts by weight or less, more preferably 10 parts by weight or less, and 1 part by weight Servings below are better.

The acrylic rubber composition of the present invention can be prepared by blending a crosslinking agent and other blending agents as needed in the acrylic rubber, and mixing them using a Banbury mixer, a kneader, and the like. , Kneading, and then use the kneading roller for further kneading.

The mixing order of each component is not particularly limited, but it is preferred that after sufficiently mixing the components that are difficult to cause reaction or decomposition under heat, the components that are liable to react or decompose under heat are not caused so as not to cause reaction or decomposition The temperature is mixed in a short period of time, and the component-based cross-linking agent and the like are liable to cause reaction or decomposition under heat.

＜ Rubber crosslinked products ＞

The rubber crosslinked product of the present invention is obtained by crosslinking the acrylic rubber composition of the present invention.

The rubber crosslinked product of the present invention can be produced by using the acrylic rubber composition of the present invention and a molding machine corresponding to a desired shape, such as an extruder, an injection molding machine, a compressor, and a roller. Molding is performed, and a crosslinking reaction is performed by heating, and then the shape is fixed to be a rubber crosslinked product. In this case, crosslinking may be performed after forming in advance, or forming and crosslinking may be performed at the same time. The molding temperature is usually 10 to 200 ° C, preferably 25 to 120 ° C. The crosslinking temperature is usually 130 to 220 ° C, preferably 150 to 190 ° C, and the crosslinking time is usually 2 minutes to 10 hours, and preferably 3 minutes to 5 hours. As the heating method, a method used for the crosslinked rubber such as pressure heating, steam heating, oven heating, and hot air heating may be appropriately selected.

In addition, depending on the shape, size, and the like of the rubber crosslinked product, the rubber crosslinked product of the present invention may be further heated to perform secondary crosslinking. The secondary cross-linking varies depending on the heating method, cross-linking temperature, shape, etc., but it is preferably carried out for 1 to 48 hours. The heating method and heating temperature may be appropriately selected.

The rubber crosslinked material of the present invention maintains tensile strength, elongation, hardness and the like as the basic characteristics of rubber, and at the same time has excellent compression resistance and water resistance. Therefore, by taking advantage of this characteristic, the rubber crosslinked product of the present invention is suitable for use in a wide range of fields such as transportation machinery such as automobiles, general equipment, and electrical equipment, as sealing materials such as O-rings, packaging, oil seals, and bearing seals; Sheets; buffer materials, shock-proof materials; wire covering materials; industrial tapes; pipes and hoses; sheet materials; etc.

Examples are described below.

Examples and comparative examples are given below to explain the present invention more specifically. In addition, the "part" in each case is a weight basis as long as it is not specifically limited.

Various physical properties were evaluated according to the following methods.

[Muni viscosity (ML1 + 4, 100 ° C)]

Measure the Mooney viscosity (Polymer Mooney) of acrylic rubber in accordance with JIS K6300.

[Residual amount of coagulant]

For acrylic rubber, (ICP-AES) was used for elemental analysis to measure the residual amount of coagulant in acrylic rubber. Specifically, the content ratio of the elements contained in the coagulant used is determined by elemental analysis, and the remaining amount of the coagulant is calculated from the obtained content ratio.

[Residual amount of emulsifier, anti-aging agent, and lubricant]

The acrylic rubber was dissolved in tetrahydrofuran, and (tetrahydrofuran) was used as a developing solvent, and GPC measurement was performed to measure the residual amounts of the emulsifier, anti-aging agent, and lubricant in the acrylic rubber. Specifically, from the graph obtained by GPC measurement, the integrals 峰 corresponding to the peaks of the molecular weights of the emulsifiers, anti-aging agents, and lubricants used in the production are calculated, and the integrals 値 and the peaks of the acrylic rubber are calculated. The integral 値 is compared, and the weight ratio is calculated from the molecular weight corresponding to these integral 値, thereby calculating the residual amount of the emulsifier, anti-aging agent, and lubricant.

[Recovery rate of acrylic rubber]

Calculate the ratio of the weight of the acrylic rubber in the emulsion polymerization solution to the weight (filling amount) of the monomer used for self-polymerization and its polymerization conversion rate, and the weight of the solid acrylic rubber after agglomeration and drying. Recovery of acrylic rubber.

[Normal Properties]

The acrylic rubber composition was put into a mold having a length of 15 cm, a width of 15 cm, and a depth of 0.2 cm, and was pressurized at a pressure of 10 MPa and simultaneously at 170 ° C. for 20 minutes, thereby performing primary crosslinking. Next, using a gear oven, the obtained primary crosslinked product was further heated at 170 ° C. for 4 hours to be crosslinked twice to obtain a sheet-like rubber crosslinked product. The obtained rubber crosslinked product was punched with a No. 3 dumbbell to prepare a test piece. Next, using this test piece, the tensile strength and elongation were measured in accordance with JIS K6251.

[Heat aging test]

The prepared test piece was made in the same manner as the test piece used for the evaluation of the normal physical properties described above. After being left in a gear oven at an environment of a temperature of 175 ° C for 504 hours, the tensile strength and elongation were measured. The results were compared with the normal physical properties measured according to the above method, thereby evaluating the thermal aging resistance. The tensile strength and elongation are measured in accordance with JIS K6251.

As for the tensile strength, the larger the measured amount of the heated sample, the better the heat resistance. Regarding elongation, the change rate of the measured sample after heating is compared to the measured sample of the sample that has not been thermally aged (normal physical property measurement), that is, the elongation change rate (percentage) is close to 0, which indicates heat resistance. Excellent sex.

[Compression set]

Using a mold, the acrylic rubber composition was pressurized at a temperature of 170 ° C. for 20 minutes to perform primary cross-linking to obtain a cylindrical primary cross-linked product having a diameter of 29 mm and a height of 12.7 mm. Next, the obtained primary cross-linked product was further cross-linked by heating at 170 ° C. for 4 hours using a gear oven to obtain a cylindrical rubber cross-linked product. Next, using the obtained rubber cross-linked product, in accordance with JIS K6262, the rubber cross-linked product was compressed at 25%. After being left in an environment at 175 ° C for 70 hours, the compression set was measured. The smaller this value is, the better the compression set resistance is.

[Water resistance]

The acrylic rubber composition was placed in a mold having a length of 15 cm, a width of 15 cm, and a depth of 0.2 cm, and was pressurized at a pressure of 10 MPa and at the same time at 170 ° C. for 20 minutes, thereby performing primary crosslinking. Next, the obtained primary crosslinked product was further cross-linked by heating at 170 ° C. for 4 hours using a gear oven to obtain a sheet-like rubber crosslinked product. Next, a 3 cm × 2 cm × 0.2 cm test piece was cut out of the obtained sheet-like rubber cross-linked product, and the obtained test piece was immersed in distilled water adjusted to a temperature of 80 ° C. for 70 hours in accordance with JIS K6258. In the test, the volume change rate of the test piece before and after immersion was measured according to the following formula. The smaller the volume change rate before and after immersion, the more the swelling of water is suppressed, and it can be judged that the water resistance is excellent.

Volume change rate before and after immersion (%) = (volume of test piece after immersion-volume of test piece before immersion) ÷ volume of test piece before immersion × 100

[Manufacturing example 1]

In a mixing vessel equipped with a homogenizer, 46.294 parts of pure water, 49.3 parts of ethyl acrylate, 49.3 parts of n-butyl acrylate, 1.4 parts of fumaric acid mono-n-butyl ester, and 0.709 parts of anion are charged. Surfactant sodium lauryl sulfate (trade name "EMAL 2FG", manufactured by Kao Corporation) and 1.82 parts of polyoxyethylene lauryl ether (trade name "EMULGEN 105") as a nonionic surfactant, weight average molecular weight : About 1500, manufactured by Kao Corporation), and stirred to obtain a monomer emulsion.

Next, in a polymerization reaction tank equipped with a thermometer and a stirring device, 170.853 parts of pure water and 2.98 parts of the monomer emulsion obtained as described above were charged and cooled to a temperature of 12 ° C. under a nitrogen stream. Next, in a polymerization reaction tank, 145.85 parts of the above-obtained monomer emulsion, 0.00033 parts of ferrous sulfate as a reducing agent, 0.264 parts of sodium ascorbate as a reducing agent, and polymerization were continuously dropped over 3 hours. 7.72 parts of a 2.85 wt% potassium persulfate aqueous solution (the amount of potassium persulfate is 0.22 parts) of the starter. Thereafter, the temperature in the polymerization reaction tank was maintained at 23 ° C., and the reaction was continued for 1 hour, and the polymerization conversion rate was confirmed to be 95%. Hydroquinone was added as a polymerization terminator to stop the polymerization reaction to obtain an emulsion polymerization solution. .

Next, based on 100 parts of the emulsified polymerization solution obtained by polymerization, 0.3 part of 3- (3,5-bis-tertiarybutyl-4-hydroxyphenyl) propanoic acid octadecyl ester as an anti-aging agent ( octadecyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) (trade name "Irganox 1076", manufactured by BASF) (compared to the total of the monomers used in the preparation of the emulsion polymerization solution (also That is, 100 parts of ethyl acrylate, n-butyl acrylate, and mono-n-butyl fumarate are 1 part) and 0.011 parts of polyethylene oxide (weight average molecular weight (Mw) = 100,000) (relative to A total of 100 parts of filling monomers used in the production of the emulsion polymerization solution was 0.039 parts) and 0.075 parts of polyoxyethylene stearate phosphate (trade name "PHOSPHANOL RL-210") as a lubricant, weight average molecular weight: Approximately 500 (manufactured by Toho Chemical Industry Co., Ltd.) (0.25 parts with respect to 100 parts in total of the loading monomers used in the production of the emulsion polymerization solution) were mixed to obtain a mixed solution. Next, the obtained mixed liquid was transferred to a coagulation tank, and 60 parts of industrial water was added to 100 parts of the mixed liquid. After the temperature was raised to 85 ° C, the mixed liquid was stirred at a temperature of 85 ° C and continuously added as a coagulation. 3.3 parts of sodium sulfate (11 parts with respect to 100 parts of the polymer contained in the mixed solution), whereby the polymer was agglomerated to obtain the water-containing pellets of the acrylic rubber (A1).

Next, 194 parts of industrial water was added to 100 parts of the solid content of the water-containing pellets obtained above, and after stirring at 15 ° C. for 5 minutes in the aggregation tank, the water was discharged from the aggregation tank to wash the water-containing pellets. Further, in this production example, such water washing was repeated four times.

Next, a sulfuric acid aqueous solution (pH = 3) obtained by mixing 194 parts of industrial water and 0.13 parts of concentrated sulfuric acid was added to 100 parts of the solid content of the water-containing agglomerated granules which had been washed with water, and stirred at 15 ° C in a coagulation tank. After 5 minutes, the water was drained from the coagulation tank to pickle the water-containing pellets. The pH of the water-containing pellets after pickling (the pH of the water in the water-containing pellets) was measured and found to be pH = 3. Next, 194 parts of pure water was added to 100 parts of the solid content of the water-containing pellets that had been pickled, and after stirring at 15 ° C for 5 minutes in the aggregation tank, water was discharged from the aggregation tank to purify the water-containing pellets. Washed with water. A hot air dryer was used to dry the water-containing pellets that had been washed with pure water at 110 ° C for 1 hour, thereby obtaining a solid acrylic rubber (A1).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A1) was 31, the recovery rate of the acrylic rubber (A1) was 100%, and the composition of the acrylic rubber (A1) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, with respect to the acrylic rubber (A1), the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A1) were measured according to the above method. The results are shown in Table 1-2.

[Manufacture example 2]

The amount of sodium lauryl sulfate used as an anionic surfactant was changed from 0.709 parts to 0.624 parts, and the amount of polyoxyethylene dodecyl ether used as a nonionic surfactant was changed from 1.82 parts to 1.5 parts. Other than that, it carried out similarly to the manufacture example 1, and obtained the monomer emulsion. Next, it carried out similarly to the manufacture example 1 except using the obtained monomer emulsion, and obtained the solid acrylic rubber (A2).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A2) was 33, the recovery rate of the acrylic rubber (A2) was 100%, and the composition of the acrylic rubber (A2) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, for the acrylic rubber (A2), the residual amount of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A2) was measured according to the above method. The results are shown in Table 1-2.

[Manufacture example 3]

The amount of sodium lauryl sulfate used as an anionic surfactant was changed from 0.709 parts to 0.567 parts, and the amount of polyoxyethylene dodecyl ether used as a nonionic surfactant was changed from 1.82 parts to 1.4 parts. Other than that, it carried out similarly to the manufacture example 1, and obtained the monomer emulsion. Next, except using the obtained monomer emulsion, it carried out similarly to the manufacture example 1, and obtained the solid acrylic rubber (A3).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A3) was 34, the recovery rate of the acrylic rubber (A3) was 100%, and the composition of the acrylic rubber (A3) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, with respect to the acrylic rubber (A3), the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A3) were measured according to the above method. The results are shown in Table 1-2.

[Manufacture example 4]

The amount of sodium lauryl sulfate used as an anionic surfactant was changed from 0.709 parts to 0.567 parts, and the amount of polyoxyethylene dodecyl ether used as a nonionic surfactant was changed from 1.82 parts to 1.4 parts. Other than that, it carried out similarly to the manufacture example 1, and obtained the monomer emulsion.

Next, in a polymerization reaction tank equipped with a thermometer and a stirring device, 179 parts of pure water and 2.98 parts of the monomer emulsion obtained as described above were charged and cooled to a temperature of 12 ° C. under a nitrogen stream. Next, in the polymerization reaction tank, 0.00033 parts of ferrous sulfate as a reducing agent, 0.264 parts of sodium formaldehyde sulfoxylate, and 0.22 parts of potassium persulfate as a polymerization initiator were charged at one time. In the polymerization reaction tank, 145.29 parts of the monomer emulsion obtained above was continuously dripped over 3 hours. Thereafter, the temperature in the polymerization reaction tank was maintained at 23 ° C., the reaction was continued for 1 hour, and the polymerization conversion rate was confirmed to be 90%. Hydroquinone was added as a polymerization terminator to stop the polymerization reaction to obtain an emulsion polymerization solution.

Next, the emulsion polymerization solution obtained above was performed in the same manner as in Production Example 1. An anti-aging agent and a slip agent were added and mixed to obtain a mixed solution, and the obtained mixed solution was subjected to agglomeration operation in the same manner, whereby Water-containing pellets of acrylic rubber (A4) were obtained. The obtained water-containing pellets were similarly washed four times with water, acid, pure water, and dried to obtain a solid acrylic rubber (A4).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A4) was 31, the recovery rate of the acrylic rubber (A4) was 100%, and the composition of the acrylic rubber (A4) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A4) were measured according to the above method. The results are shown in Table 1-2.

[Manufacturing example 5]

An emulsion polymerization solution was obtained in the same manner as in Production Example 1 except that the monomer emulsion obtained in the same manner as in Production Example 3 was used. Next, the obtained emulsion polymerization liquid was carried out in the same manner as in Production Example 1. An anti-aging agent and a slip agent were added and mixed to obtain a mixed liquid, and the obtained mixed liquid was subjected to agglomeration operation to obtain acrylic acid. Water-containing pellets of rubber (A5).

Next, except that the number of times of washing with water was changed from four to two, the same procedure as in Production Example 1 was performed, and washing with water, pickling, washing with pure water, and drying were performed to obtain a solid acrylic rubber (A5). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A5) was 33, the recovery rate of the acrylic rubber (A5) was 100%, and the composition of the acrylic rubber (A5) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A5) were measured according to the above method. The results are shown in Table 1-2.

[Manufacturing example 6]

An emulsion polymerization solution was obtained in the same manner as in Production Example 1 except that the monomer emulsion obtained in the same manner as in Production Example 3 was used. Next, the obtained emulsion polymerization liquid was carried out in the same manner as in Production Example 1. An anti-aging agent and a slip agent were added and mixed to obtain a mixed liquid, and the obtained mixed liquid was subjected to agglomeration operation to obtain acrylic acid. Water-containing pellets of rubber (A6).

Next, the number of times of washing with water was changed from four to one, and it was carried out in the same manner as in Production Example 1. Water washing, pickling, pure water washing, and drying were performed to obtain a solid acrylic rubber (A6). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A6) was 32, the recovery rate of the acrylic rubber (A6) was 100%, and the composition of the acrylic rubber (A6) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A6) were measured according to the above method. The results are shown in Table 1-2.

[Manufacturing Example 7]

As a coagulant used in the aggregation operation, 3.3 parts of magnesium sulfate was used instead of 3.3 parts of sodium sulfate, and the same procedure as in Production Example 3 was performed to obtain water-containing pellets of acrylic rubber (A7). Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing, and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A7).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A7) was 33, the recovery rate of the acrylic rubber (A7) was 100%, and the composition of the acrylic rubber (A7) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A7) were measured according to the above method. The results are shown in Table 1-2.

[Manufacture example 8]

As a coagulant used in the coagulation operation, 3.3 parts of calcium chloride was used instead of 3.3 parts of sodium sulfate, and the same procedure as in Production Example 3 was performed to obtain water-containing pellets of acrylic rubber (A8). Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing, and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A8).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A8) was 35, the recovery rate of the acrylic rubber (A8) was 100%, and the composition of the acrylic rubber (A8) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A8) were measured according to the above method. The results are shown in Table 1-2.

[Manufacturing Example 9]

As an anti-aging agent blended with 100 parts by weight of the emulsified polymerization solution obtained by polymerization, 0.3 part of 2,4-bis [(octylthio) methyl] -6-methylphenol (trade name " Irganoxgan1520L ", manufactured by BASF Corporation (1 part with respect to 100 parts of the total amount of the filling monomer used in the production of the emulsion polymerization solution) to replace 0.3 part of 3- (3,5-bis-tertiarybutyl-4- Stearyl hydroxyphenyl) propionate. Other than that, it carried out similarly to the manufacture example 3, and obtained the water-containing pellet of acrylic rubber (A9).

Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing, and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A9). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A9) was 34, the recovery rate of the acrylic rubber (A9) was 100%, and the composition of the acrylic rubber (A9) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A9) were measured according to the above method. The results are shown in Table 1-2.

[Manufacturing example 10]

As an anti-aging agent blended with 100 parts by weight of the emulsified polymerization solution obtained by polymerization, 0.3 parts of 2-mercaptobenzimidazole (trade name "NOCRAC MB", manufactured by Onai Shinko Chemical Industry Co., Ltd.) (relative to A total of 100 parts of the filling monomer used in the production of the emulsion polymerization solution was 1 part) to replace 0.3 part of 3- (3,5-bis-tertiarybutyl-4-hydroxyphenyl) propanoic acid octadecyl ester. Other than that, it carried out similarly to the manufacture example 3, and obtained the water-containing pellet of acrylic rubber (A10).

Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A10). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A10) was 33, the recovery rate of the acrylic rubber (A10) was 100%, and the composition of the acrylic rubber (A10) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amount of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A10) was measured according to the above method. The results are shown in Table 1-2.

[Manufacturing Example 11]

As an anti-aging agent blended with 100 parts by weight of the emulsified polymerization solution obtained by polymerization, 0.3 part of 4, 4'-bis (α, α-dimethylbenzyl) diphenylamine (trade name "NOCRAC" "CD", manufactured by Ochii Shinko Chemical Industry Co., Ltd. (1 part based on 100 parts of the total amount of the filling monomer used in the production of the emulsion polymerization solution) to replace 0.3 part of 3- (3,5-bis-tertiary butyl). 4-Hydroxyphenyl) propionic acid stearyl ester. Other than that, it carried out similarly to the manufacture example 3, and obtained the water-containing pellet of acrylic rubber (A11).

Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A11). The obtained acrylic rubber (A11) had a Mooney viscosity (ML1 + 4, 100 ° C) of 32, the recovery rate of the acrylic rubber (A11) was 100%, and the composition of the acrylic rubber (A11) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A11) were measured according to the above method. The results are shown in Table 1-2.

[Manufacture example 12]

As an anti-aging agent blended with 100 parts by weight of the emulsified polymerization solution obtained by polymerization, 0.3 parts of mono (or di or tri) (α-methylbenzyl) phenol (trade name "NOCRAC SP" is used). , Manufactured by Onai Shinko Chemical Industry Co., Ltd. (1 part with respect to 100 parts in total of the monomers used in the production of the emulsion polymerization solution) to replace 0.3 part of 3- (3,5-bis-tertiary butyl-4 -Hydroxyphenyl) octadecyl propionate. Other than that, it carried out similarly to the manufacture example 1, and obtained the water-containing pellet of acrylic rubber (A12).

Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A12). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A12) was 31, the recovery rate of the acrylic rubber (A12) was 100%, and the composition of the acrylic rubber (A12) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A12) were measured according to the above method. The results are shown in Table 1-2.

[Production Example 13]

As a lubricant agent blended with 100 parts by weight of the emulsified polymerization solution obtained by polymerization, 0.075 parts of a higher fatty acid (trade name "Moldwiz Int21G", manufactured by Ba Industries, Ltd.) is used (relative to that used in the production of the emulsified polymerization solution) A total of 100 parts of the filling monomer was 0.25 parts) to replace 0.075 parts of polyoxyethylene stearate phosphate. Other than that, it carried out similarly to the manufacture example 1, and obtained the water-containing pellet of acrylic rubber (A13).

Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing, and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A13). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A13) was 33, the recovery rate of the acrylic rubber (A13) was 100%, and the composition of the acrylic rubber (A13) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A13) were measured according to the above method. The results are shown in Table 1-2.

[Manufacture example 14]

As a lubricant agent blended with 100 parts by weight of the emulsified polymerization solution obtained by polymerization, 0.075 parts of a higher fatty acid (trade name "Moldwiz Int21G", manufactured by Ba Industries, Ltd.) is used (relative to that used in the production of the emulsified polymerization solution) (Total 100 parts of the loading monomer is 0.25 parts) to replace 0.075 parts of polyoxyethylene stearate phosphate, and as a coagulant used in the coagulation operation, 3.3 parts of sodium chloride is used instead of 3.3 parts. Sodium sulfate. Other than that, it carried out similarly to the manufacture example 12, and obtained the water-containing pellet of acrylic rubber (A13).

Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A14). The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A14) was 33, the recovery rate of the acrylic rubber (A14) was 100%, and the composition of the acrylic rubber (A14) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A14) were measured according to the above method. The results are shown in Table 1-2.

[Manufacturing Example 15]

The amount of sodium sulfate used as the coagulant used for the coagulation operation was changed from 3.3 parts to 0.3 parts (1 part with respect to 100 parts of the polymer contained in the mixed solution). In the same manner, water-containing pellets of the acrylic rubber (A15) were obtained. Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing, and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A15).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A15) was 33, the recovery rate of the acrylic rubber (A15) was 42%, and the composition of the acrylic rubber (A15) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amount of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A15) was measured according to the method described above. The results are shown in Table 1-2.

[Manufacture example 16]

The amount of sodium sulfate used as the coagulant used in the coagulation operation was changed from 3.3 parts to 0.6 parts (2 parts with respect to 100 parts of the polymer contained in the mixed solution). In the same manner, water-containing pellets of acrylic rubber (A16) were obtained. Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A16).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A16) was 33, the recovery rate of the acrylic rubber (A16) was 63%, and the composition of the acrylic rubber (A16) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A16) were measured according to the method described above. The results are shown in Table 1-2.

[Manufacturing Example 17]

The amount of sodium sulfate used as the coagulant used in the coagulation operation was changed from 3.3 parts to 10 parts (33.3 parts with respect to 100 parts of the polymer contained in the mixed solution). In the same manner, water-containing pellets of acrylic rubber (A17) were obtained. Next, the obtained water-containing pellets were subjected to water washing, acid washing, pure water washing and drying four times in the same manner as in Production Example 1, thereby obtaining a solid acrylic rubber (A17).

The acrylic viscosity (ML1 + 4, 100 ° C) of the obtained acrylic rubber (A17) was 33, the recovery rate of the acrylic rubber (A17) was 100%, and the composition of the acrylic rubber (A17) was 49.3% by weight of ethyl acrylate units , 49.3% by weight of n-butyl acrylate units, and 1.4% by weight of fumarate mono-n-butyl units. In addition, the residual amounts of the coagulant, surfactant, lubricant, and anti-aging agent in the acrylic rubber (A17) were measured according to the above method. The results are shown in Table 1-2.

[Example 1]

Using a Banbury mixer, 30 parts of clay (trade name "Satintone Clay 5A", manufactured by Takehara Chemical Industry Co., Ltd., calcined kaolin), and 15 parts were added to 100 parts of the acrylic rubber (A1) obtained in Production Example 1. Silica (trade name "CARPLEX 1120", manufactured by Evonik), 35 parts of silica (trade name "CARPLEX 67", manufactured by Evonik), 2 parts of stearic acid, 1 part of ester-based wax (trade name) "Gleck G-8205", manufactured by DAINIPPON INK AND CHEMICALS), 2 parts of 4, 4'-bis (α, α-dimethylbenzyl) diphenylamine (4, 4'-bis (α, α-dimethylbenzyl) ) diphenylamine) (trade name "NOCRAC CD", manufactured by Onai Shinko Chemical Co., Ltd.), and 1 part of 3-methacryloxypropyltrimethoxysilane (trade name "KBM-503" , Manufactured by Shin-Etsu Silicon Co., Ltd., silane coupling agent), and mixed at 50 ° C for 5 minutes. Next, the obtained mixture was transferred to a roller at 50 ° C, and 0.6 part of hexamethylenediamine carbamate (trade name "Diak # 1", manufactured by DuPont elastomers, blended with aliphatic polyvalent) was blended. Amine compound), and 2 parts of 1,3-di-o-tolylguanidine ("NOCCELER DT", manufactured by Onai Shinko Chemical Industry Co., Ltd., cross-linking accelerator) and kneaded to obtain an acrylic rubber composition .

Next, using the obtained acrylic rubber composition, according to the method described above, each measurement and evaluation of normal physical properties, thermal aging test, compression set, and water resistance were performed. The results are shown in Table 2.

[Examples 2 to 16]

An acrylic rubber composition was obtained in the same manner as in Example 1 except that the acrylic rubbers (A2) to (A16) obtained in Production Examples 2 to 16 were used instead of the acrylic rubber (A1) obtained in Production Example 1. The measurement and evaluation results are shown in Table 2 in the same manner.

[Comparative Example 1]

An acrylic rubber composition was obtained in the same manner as in Example 1 except that the acrylic rubber (A17) obtained in Manufacturing Example 17 was used instead of the acrylic rubber (A1) obtained in Manufacturing Example 1. The evaluation results are shown in Table 2.

[Table 1-1]

[Table 1-2] (* 1) The addition amount of the admixture used to prepare the monomer emulsion is expressed as the blending amount with respect to 100 parts of the loading monomer. (* 2) The amount of the blending agent added to the emulsified polymerization solution before aggregation is expressed in terms of the blended amount of 100 parts of the emulsified polymerization solution. (* 3) The addition amount of the coagulant used in the coagulation step is a blending amount of 100 parts with respect to the mixed solution obtained by adding an anti-aging agent, polyethylene oxide, and a lubricant to the emulsified polymerization solution. And said.

[Table 2]

As shown in Tables 1-1, 1-2, and 2, the acrylic rubbers obtained in Production Examples 1 to 16 have residual amounts of coagulants such as 10 wt ppm or more and 10,000 wt ppm or less. All the rubber crosslinked materials are those having excellent compression set resistance and water resistance (Examples 1 to 16). In addition, it can also be confirmed from Tables 1-1 and 1-2 that the anti-aging agent and lubricant added to the emulsion polymerization solution before coagulation have not been substantially removed even after coagulation and drying, and the blending amount is The same amount of anti-aging agent and lubricant remained in the acrylic rubber.

On the other hand, the acrylic rubber obtained in Production Example 17 had a residual amount of agglomerating agent exceeding 10,000 ppm by weight. Using the rubber crosslinked product obtained therefrom was inferior in water resistance (Comparative Example 1).

no

no

Claims (14)

An acrylic rubber having a residual amount of an aggregating agent of 10 to 10,000 ppm by weight. The acrylic rubber according to claim 1, wherein the residual amount of the coagulant is 10 ppm by weight or more and 3,500 ppm by weight or less. The acrylic rubber according to claim 1 or 2, wherein the residual amount of the coagulant is 500 ppm by weight or more and 3,500 ppm by weight or less. The acrylic rubber according to claim 1 or 2, wherein the coagulant is a metal salt of 1 to 3 valence. The acrylic rubber according to claim 4, wherein the coagulant is calcium chloride, sodium chloride, magnesium sulfate or sodium sulfate. The acrylic rubber according to claim 1 or 2, wherein the residual amount of the emulsifier is 10 ppm by weight or more and 22,000 ppm by weight or less. The acrylic rubber according to claim 1 or 2, wherein the residual amount of the slip agent is 0.1 to 0.4% by weight. The acrylic rubber according to claim 1 or 2, wherein the residual amount of the anti-aging agent is 500 ppm by weight or more and 12,000 ppm by weight or less. The acrylic rubber according to claim 1 or 2, wherein the content of the acrylic rubber component is 95% by weight or more. A method for manufacturing acrylic rubber, which is a method for manufacturing an acrylic rubber as described in claim 1 or 2, and has the following steps: An emulsification polymerization step is an emulsion polymerization of monomers used to form acrylic rubber to obtain An emulsification polymerization solution; a coagulation step, in which a coagulant is added to the emulsion polymerization solution to obtain water-containing pellets; a washing step, in which the water-containing pellets are washed; and a drying step, in which the water-containing pellets which have been washed are dried. The method for producing an acrylic rubber according to claim 10, wherein the addition amount of the coagulant is 3 to 20 parts by weight based on 100 parts by weight of the acrylic rubber component contained in the emulsion polymerization solution. The method for producing an acrylic rubber according to claim 10, further comprising an adding step, wherein the emulsification polymerization solution before aggregation is contained in a polymer selected from a lubricant, an anti-aging agent, and an ethylene oxide-based polymer. At least one of them. An acrylic rubber composition comprising the acrylic rubber and a crosslinking agent according to claim 1 or 2. A rubber crosslinked product obtained by crosslinking the acrylic rubber composition according to claim 13.