KR20230026335A - Banbury acrylic rubber veil with excellent processability and water resistance - Google Patents

Abstract

Banbury Provides an acrylic rubber veil with excellent workability and water resistance. The acrylic rubber veil according to the present invention is made of acrylic rubber having an ionic reactive group, the gel amount of the methyl ethyl ketone insoluble content is 15% by weight or less, and all values randomly measured at 20 points are in the range of (average value ± 5)% by weight pH is 6 or less, the amount of ash is 0.0005% by weight or more and 0.2% by weight or less, and the total amount of sodium, sulfur, calcium, magnesium, and phosphorus in the ash is 90% by weight or more.

Description

Banbury acrylic rubber veil with excellent processability and water resistance

The present invention relates to an acrylic rubber veil, a manufacturing method thereof, a rubber composition, and a crosslinked rubber product, and more particularly, to an acrylic rubber veil excellent in Banbury processability, strength characteristics, compression set resistance, and water resistance, and a manufacturing method thereof , It relates to a rubber composition comprising the acrylic rubber veil and a rubber crosslinked product obtained by crosslinking the same.

Acrylic rubber is a polymer containing acrylic acid ester as a main component, and is generally known as a rubber having excellent heat resistance, oil resistance, and ozone resistance, and is widely used in automobile-related fields and the like.

For example, in Patent Document 1 (Japanese Unexamined Patent Publication No. 11-12427), ethyl acrylate, butyl acrylate, methoxyethyl acrylate, acrylonitrile, and allyl methacrylate or cyclopentenyloxyethyl acrylate 100 parts of a monomer component comprising a monomer that introduces a carbon-carbon double bond into a side chain, such as a rate, 4 parts of sodium lauryl sulfate, 0.25 part of p-menthane hydroperoxide, 0.01 part of ferrous sulfate, ethylenediaminetetraacetic acid 0.025 parts of sodium, 0.04 parts of sodium formaldehyde sulfoxylate, and 0.01 to 0.05 parts of t-dodecylmercaptan as a chain transfer agent were put into a nitrogen-purged autoclave, and the conversion rate of the monomer mixture reached 100% at a reaction temperature of 30 degrees The resulting latex was added to a 0.25% calcium chloride aqueous solution to coagulate, and the coagulated material was sufficiently washed with water, dried at about 90 ° C. for 3 hours, and 1,3-bis (t-butylperoxyisopropyl) Disclosed are an acrylic rubber and a crosslinking composition that are crosslinked with organic peroxides such as benzene and have excellent extrusion processability and scorch properties. However, the acrylic rubber obtained by this method is a crumb-like acrylic rubber, which is tacky and has poor working efficiency, and also has insufficient Banbury processability, and has poor injection moldability, storage stability, compression set resistance, water resistance, and strength characteristics. I had a problem with this falling off.

On the other hand, regarding veiled acrylic rubber, for example, in Patent Document 2 (Japanese Unexamined Patent Publication No. 2006-328239), a step of obtaining a crumb slurry containing a crumb-like rubber polymer by bringing polymer latex into contact with a coagulating liquid And, a step of crushing the crumb-like rubber polymer contained in the crumb slurry with a mixer having an agitation/crushing function with an agitation power of 1 kW/m ³ or more, and removing moisture from the crumb slurry in which the crumb-like rubber polymer was crushed A method for producing a rubber polymer comprising a dehydration step of obtaining a crumb-like rubber polymer and a step of heating and drying the crumb-like rubber polymer from which moisture has been removed is disclosed, wherein the dried crumb is introduced into a baler in the form of flakes and compressed It is described to be veiled. As the rubber polymer used here, an unsaturated nitrile-conjugated diene copolymer latex obtained by emulsion polymerization is specifically shown, and also ethyl acrylate/n-butyl acrylate copolymer and ethyl acrylate/n-butyl acrylate / 2-Methoxyethyl acrylate copolymer and the like are shown to be applicable to copolymers composed only of acrylates. However, an acrylic rubber veil composed of only acrylate has a problem in that crosslinked rubber properties such as heat resistance and compression set resistance are inferior.

As an acrylic rubber that has an ionic reactive group with excellent heat resistance and compression set resistance and is baled, for example, in Patent Document 3 (Pamphlet of International Publication No. 2018/116828), ethyl acrylate, n-butyl acrylate, and fumaric acid A monomer component composed of mono-n-butyl was emulsified with sodium lauryl sulfate, polyethylene glycol monostearate, and water as emulsifiers, and cumene hydroperoxide as an organic radical generator was added to emulsion polymerization until the polymerization conversion rate reached 95%. Acrylic rubber latex was added to an aqueous solution of magnesium sulfate and dimethylamine-ammonia-epichlorohydrin polycondensate as a polymer coagulant, and then stirred at 85° C. to form a crumb slurry, and then the crumb slurry was washed once with water and then 100 mesh. Disclosed is a method of recovering crumb-like acrylic rubber by passing the entire amount through a wire mesh and capturing only the solid content. According to this method, it is described that the obtained crumb in a moist state is dehydrated by centrifugation or the like, dried at 50 to 120 ° C. by a band dryer or the like, introduced into a baler, compressed and baled. However, in this method, a large number of semi-solidified water-containing crumbs are generated during the coagulation reaction and adhere to the coagulation tank in large quantities, problems such as inability to sufficiently remove the coagulant and emulsifier by washing, and acrylic rubber itself. There were problems such as poor Banbury processability and injection moldability, poor storage stability because air could not be sufficiently removed even if a bale was produced, and poor water resistance when reacted with a crosslinking agent to form a crosslinked product.

Regarding the gel amount of the acrylic rubber, for example, in Patent Document 4 (Japanese Patent No. 3599962), 95 to 99.9% by weight of an alkyl acrylate or alkoxyalkyl acrylate contains two or more radical reactive unsaturated groups having different reactivity. An acrylic rubber having a gel fraction of 5% by weight or less, which is an acetone insoluble content obtained by copolymerizing 0.1 to 5% by weight of a polymerizable monomer having a radical polymerization initiator, a reinforcing filler, and an organic peroxide-based vulcanizing agent. Disclosed is an acrylic rubber composition excellent in extrusion processability such as surface skin. The acrylic rubber with a very small gel fraction used herein is an acrylic rubber with a high gel fraction (60%) obtained in a normal acidic range (pH 4 before polymerization, pH 3.4 after polymerization), and the polymerization solution is hydrogen carbonate. It is obtained by adjusting pH to 6-8 with sodium etc. Specifically, after adding water, sodium lauryl sulfate, polyoxyethylene nonylphenyl ether, sodium carbonate, and boric acid as emulsifiers and adjusting the temperature to 75 ° C, organic radical generating agents t-butyl hydroperoxide, longite, ethylene Disodium diamine tetraacetate and ferrous sulfate were added (pH at this time was 7.1), and then the monomer components of ethyl acrylate and allyl methacrylate were added dropwise to perform emulsion polymerization, and the obtained emulsion (pH 7) was It is salted out using an aqueous sodium sulfate solution, washed with water and dried to obtain acrylic rubber. However, acrylic rubber containing (meth)acrylic acid ester as a main component is decomposed in a neutral to alkaline range, and even if processability is improved, storage stability and strength characteristics are poor, and crosslinkability, compression set resistance and water resistance are poor. There was also this falling problem. Further, in this specification, veiling the acrylic rubber is not described.

Further, in Patent Document 5 (Pamphlet of International Publication No. 2018/143101), a (meth)acrylic acid ester and an ionic crosslinkable monomer are emulsion-polymerized, and the complex viscosity at 100°C ([η] 100°C) is 3,500 Pa. s or less, and the ratio of the complex viscosity at 60°C ([η]60°C) to the complex viscosity at 100°C ([η]100°C) ([η]100°C/[η]60°C) is 0.8 A technique for improving the extrusion moldability of a rubber composition containing a reinforcing agent and a crosslinking agent, particularly, discharge amount, discharge length, and surface skin properties, using the following acrylic rubber is disclosed. The amount of gel, which is the THF (tetrahydrofuran) insoluble component of the acrylic rubber used in the art, is 80% by weight or less, preferably 5 to 80% by weight, and preferably present as much as possible in the range of 70% or less, , it is described that the extrudability deteriorates when the gel amount is less than 5%. In addition, the weight average molecular weight (Mw) of the acrylic rubber used is 200,000 to 1,000,000, and it is described that when the weight average molecular weight (Mw) exceeds 1,000,000, the viscoelasticity of the acrylic rubber becomes excessively high, which is not preferable. However, there is no description about methods for improving processability, strength characteristics, and water resistance of Banbury or injection molding.

Japanese Unexamined Patent Publication No. 11-12427 Japanese Unexamined Patent Publication No. 2006-328239 International Publication No. 2018/116828 pamphlet Japanese Patent No. 3599962 International Publication No. 2018/143101 pamphlet

The present invention, which has been made in view of the reality of the prior art, is an acrylic rubber veil excellent in Banbury processability, strength characteristics, compression set resistance, and water resistance, a method for manufacturing the same, a rubber composition comprising the acrylic rubber veil, and the same It aims at providing a rubber crosslinked product formed by crosslinking.

As a result of intensive research in view of the above problems, the inventors of the present invention have found that an acrylic rubber veil made of acrylic rubber having an ion reactive group and having a specific gel amount, gel amount variation, pH, ash content, and ash content amount of methyl ethyl ketone insoluble content is specified. , Banbury workability, strength characteristics, compression set resistance, and water resistance were found to be remarkably excellent.

Regarding Banbury workability, the present inventors found that the smaller the gel amount of the methyl ethyl ketone insoluble component in the acrylic rubber veil, the better. The amount of gel insoluble in methyl ethyl ketone in the acrylic rubber veil occurs during the polymerization reaction of acrylic rubber, and in particular, it is difficult to control because it rapidly increases when the polymerization conversion rate is increased to improve strength characteristics, but chain transfer agents are present in the latter half of the polymerization reaction What can be suppressed to some extent by emulsion polymerization under the conditions, preferably, by melt-kneading and drying acrylic rubber in a screw-type twin-screw extrusion dryer in a state that does not contain substantially water in a gel amount of a specific solvent-insoluble component that has rapidly increased. It was found that the Banbury workability of the acrylic rubber veil can be remarkably improved with little variation in the amount of gel. The present inventors also found that the acrylic rubber bale prepared by melt-kneading and drying in a state in which water was almost removed (moisture content less than 1% by weight) with a screw-type twin-screw extrusion dryer was highly balanced in Banbury processability and strength characteristics. paid

Regarding water resistance, the present inventors have found that it is greatly influenced by the amount of ash and ash components in the acrylic rubber veil. In particular, it is quite difficult to remove ash from acrylic rubber produced using a large amount of emulsifier or coagulant, but the washing efficiency and dehydration of hydrous crumb produced by dewatering with a specific screw-type twin-screw extrusion dryer, particularly coagulating with a specific method It was found that the water resistance could be improved by significantly improving the ash removal efficiency of the city and significantly reducing the amount of ash of the acrylic rubber veil. In particular, the present inventors have found that the acrylic rubber veil obtained by increasing the ratio of the specific particle size of the hydrous crumb generated in the solidification step and performing washing, dehydration, and drying has properties such as Banbury workability, strength characteristics, and compression set resistance characteristics. It was found that the water resistance can be remarkably improved without damaging the In addition, the present inventors, in addition to the above ash content and ash content amount, when using a phosphoric acid ester salt or a sulfuric ester salt as an emulsifier and / or using an alkali metal salt or periodic table group 2 metal salt as a coagulant, acrylic rubber veil It was found that the water resistance of can be significantly improved, and the injection moldability and adhesion to metal are also reduced, and the workability is also excellent.

The present inventors also found that an acrylic rubber veil made of an acrylic rubber having an ion-reactive group that reacts ionically with a crosslinking agent such as a carboxyl group, an epoxy group, or a chlorine atom has excellent state physical properties including compression set resistance and strength characteristics. In addition, it was found that the strength characteristics and compression set resistance characteristics of the acrylic rubber veil are highly balanced when it has the ionic reactive group and the number average molecular weight of the acrylic rubber is within a specific range.

The present inventors, in the GPC measurement of ion-reactive acrylic rubber copolymerized with such an ion-reactive group or monomer containing an ion-reactive group, radicals copolymerized with ethyl acrylate and dihydrodicyclopentenyl acrylate, etc. of the prior art It was not possible to sufficiently dissolve the reactive acrylic rubber in tetrahydrofuran used for GPC measurement, and it was not possible to measure each molecular weight or molecular weight distribution clearly and reproducibly. However, a specific solvent having a higher SP value than tetrahydrofuran was used as a developing solvent. By doing so, it can be clearly dissolved and reproducibly measured, and furthermore, by setting each characteristic value within a specific range, the Banbury processability, strength characteristics, compression set resistance, and water resistance of the acrylic rubber veil can be highly controlled.

The present inventors also found that an acrylic rubber veil having a ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of acrylic rubber in a specific range has Banbury processability, strength characteristics, and compression set resistance , and it was found that the injection moldability can be remarkably improved without impairing water resistance. The present inventors also emulsified a monomer component including an ion-reactive group-containing monomer with water and an emulsifier, followed by emulsion polymerization in the presence of a redox catalyst composed of an organic radical generator such as diisopropylbenzene hydroperoxide and a reducing agent. initiation, emulsion polymerization by adding a chain transfer agent batchwise during the polymerization without initially adding it, coagulating the emulsion polymerization solution in contact with a coagulant, and coagulating the hydrous crumb produced by coagulation after washing. It was found that by dewatering, drying, and molding with a screw-type twin-screw extrusion dryer, it was possible to produce an acrylic rubber veil excellent in Banbury processability, strength characteristics, compression set resistance, and water resistance, as well as remarkably excellent injection moldability. The number average molecular weight (Mn), the weight average molecular weight (Mw), and the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw/Mn) of the acrylic rubber produced herein can be set to a specific range, In addition, as for the injection moldability, all of the characteristics of shape forming property, fusing property, and releasability were remarkably excellent.

The present inventors further determined the number average molecular weight (Mn) and the weight average by drying acrylic rubber using a specific extrusion dryer and melt extrusion drying acrylic rubber under optimum shear conditions using specific extrusion drying. By widening the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) to a certain extent without damaging the molecular weight (Mw), Banbury processability, injection moldability, strength characteristics, and compression set resistance are improved. It has been found that highly balanced acrylic rubber bales can be produced.

The present inventors also found that an acrylic rubber veil laminated with sheet-shaped dried rubber dried under reduced pressure or melted and extruded under reduced pressure with a screw-type twin screw extrusion dryer has Banbury processability, strength characteristics, and compression set resistance. , and water resistance were excellent, and storage stability was also remarkably excellent. Acrylic rubber having specific ionic reactive groups such as carboxyl group, epoxy group, and chlorine atom is adhesive and has a high affinity for air, so it is difficult to come off once air is entrained. A large amount of air is entrained to deteriorate the storage stability, but the inventors compress the crumb-like acrylic rubber with a high-pressure baler or the like to bale, thereby removing some air and improving the storage stability of the acrylic rubber. Preferably, hydrous crumb is dried under reduced pressure with a screw-type twin-screw extrusion dryer to extrude and laminate into an air-free sheet to produce an acrylic rubber veil that contains almost no air and has remarkably excellent storage stability. I figured out what I could do. The present inventors have also found that the storage stability of such an acrylic rubber veil is correlated with the specific gravity that can be measured according to JIS K6268 crosslinked rubber-method A of density measurement using the difference in buoyancy, melt kneading and drying under reduced pressure. It was found that Shiki's acrylic rubber veil has not only storage stability, but also strength characteristics and workability such as banbury and injection molding. In addition, the inventors of the present invention found that the storage stability of an acrylic rubber veil is stable in a specific range of pH.

The present inventors also found the monomer composition of the acrylic rubber, the type of ion-reactive group, and the ratio of the complex viscosity at 100°C ([η]100°C) to the complex viscosity at 60°C ([η]60°C). ([η] 100 ° C. / [η] 60 ° C.) or water content within a specific range, it was found that the Banbury workability, strength characteristics, compression set resistance, and water resistance can be further improved.

The present inventors have found that, by using an ionic crosslinkable organic compound as a crosslinking agent, crosslinking properties are further improved and each characteristic of the obtained crosslinked rubber product is further greatly improved.

The present inventors also found that, in the rubber composition comprising the acrylic rubber veil, filler, and crosslinking agent of the present invention, by blending carbon black or silica as the filler, Banbury processability, injection moldability, and short-time crosslinking properties are excellent, In addition, it was found that the cross-linked product had highly excellent water resistance, strength characteristics, and resistance to compression set. The present inventors further found that, as the crosslinking agent, it is preferable that it is an organic compound, a polyvalent compound, or an ionic crosslinking compound. It was found that, by being a polyvalent ionic organic compound having a plurality of reactive groups, Banbury processability, injection moldability, and short-time crosslinking properties were excellent, and the crosslinked product had highly excellent water resistance, strength characteristics, and compression set resistance.

The present inventors came to complete this invention based on these knowledge.

In this way, according to the present invention, it is made of acrylic rubber having an ion-reactive group, the gel amount of the methyl ethyl ketone insoluble part is 15% by weight or less, and all values randomly measured at 20 points are within the range of (average value ± 5)% by weight , pH is 6 or less, ash content is 0.0005% by weight or more and 0.2% by weight or less, and the total amount of sodium, sulfur, calcium, magnesium, and phosphorus in the ash is 90% by weight or more.

In the acrylic rubber veil of the present invention, the ionic reactive group is preferably at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom.

In the acrylic rubber veil of the present invention, the specific gravity is preferably 0.8 or more.

In the acrylic rubber veil of the present invention, the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the acrylic rubber is preferably in the range of 1 to 25.

In the acrylic rubber veil of the present invention, the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the acrylic rubber is preferably in the range of 1.5 to 3.

In the acrylic rubber veil of the present invention, it is preferable that the number average molecular weight (Mn) of the acrylic rubber is in the range of 10,000 to 3,000,000.

In the acrylic rubber veil of the present invention, it is preferable that the number average molecular weight (Mn) of the acrylic rubber is in the range of 300,000 to 1,500,000.

In the acrylic rubber veil of the present invention, the GPC measurement solvent for the weight average molecular weight (Mw) or number average molecular weight (Mn) of the acrylic rubber is preferably a dimethylformamide solvent.

In the acrylic rubber veil of the present invention, it is preferable that the gel amount of the methyl ethyl ketone insoluble component is 5% by weight or less.

In the acrylic rubber veil of the present invention, the ratio of the complex viscosity at 100 ° C ([η] 100 ° C) and the complex viscosity at 60 ° C ([η] 60 ° C) ([η] 100 ° C / [η] 60°C) is preferably 0.7 or more.

In the acrylic rubber veil of the present invention, the water content is preferably less than 1% by weight.

In the acrylic rubber veil of the present invention, it is preferable to use a phosphoric acid ester salt or a sulfuric acid ester salt as an emulsifier and emulsion polymerization.

In the acrylic rubber veil of the present invention, it is preferable that the polymerization solution subjected to emulsion polymerization is solidified by using an alkali metal salt or a metal salt of Group 2 of the periodic table as a coagulant and then dried.

In the acrylic rubber veil of the present invention, it is preferably melt-kneaded and dried after solidification.

In the acrylic rubber veil of the present invention, it is preferable that the above melt-kneading and drying are performed in a state that does not substantially contain water.

In the acrylic rubber veil of the present invention, it is preferable that the above melt kneading and drying are performed under reduced pressure.

In the acrylic rubber veil of the present invention, it is preferable to cool at a cooling rate of 40°C/hr or more after the above melt-kneading and drying.

In the acrylic rubber veil of the present invention, it is preferable to wash, dehydrate, and dry hydrous crumbs having a particle diameter range of 710 μm to 6.7 mm in a ratio of 50% by weight or more.

According to the present invention, furthermore, at least one (meth)acrylic acid ester selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters, an ionic reactive group-containing monomer, and other monomers as necessary An emulsification step of emulsifying a monomer component consisting of water and an emulsifier;

An emulsion polymerization step of obtaining an emulsion polymerization solution by emulsion polymerization in the presence of a redox catalyst composed of a radical generator and a reducing agent;

A coagulation step of bringing the obtained emulsion polymerization liquid into contact with a coagulant to produce a hydrous crumb;

A cleaning step of cleaning the generated hydrous crumb;

The washed hydrous crumb is dehydrated to a moisture content of 1 to 40% by weight in a dewatering barrel using a screw-type twin-screw extrusion dryer having a dewatering barrel with a dehydration slit, a drying barrel under reduced pressure, and a die at the tip, and then to a drying barrel. A dehydration, drying, and molding step of drying to less than the weight percent and extruding a sheet-like dried rubber from a die;

A cooling step of cooling the extruded sheet-like dry rubber;

A cutting step of cutting the cooled sheet-like dry rubber;

Lamination step of laminating cut sheet-shaped dry rubber

There is provided a method for manufacturing an acrylic rubber veil comprising a.

It is preferable that the manufacturing method of the acrylic rubber veil of this invention is the manufacturing method of the acrylic rubber veil which manufactures the said acrylic rubber veil.

In the method for producing an acrylic rubber veil of the present invention, in the emulsion polymerization step, it is preferable to post-add a chain transfer agent batchwise during emulsion polymerization to continue polymerization.

In the production method of the acrylic rubber veil of the present invention, it is preferable that the contact between the emulsion polymerization liquid and the coagulant in the coagulation step is adding the emulsion polymerization liquid to the stirring coagulation liquid.

In the production method of the acrylic rubber veil of the present invention, in the emulsion polymerization step, it is preferable to carry out emulsion polymerization using a phosphoric acid ester salt or a sulfuric acid ester salt as an emulsifier, and the polymerization solution produced in the emulsion polymerization step is an alkali metal salt or It is preferable to coagulate by contacting with a coagulant containing a periodic table group 2 metal salt.

In the production method of the acrylic rubber veil of the present invention, it is preferable that the polymerization solution produced in the emulsion polymerization step is contacted with a coagulant to solidify, followed by melt kneading and drying. It is preferable to perform in the state of not containing, and to perform the said melt-kneading and drying under reduced pressure. Further, it is preferable that the maximum torque of the screw-type twin-screw extrusion dryer at the time of melt kneading and drying is in the range of 5 to 125 N·m. Further, in the production method of the acrylic rubber veil of the present invention, it is preferable to cool the acrylic rubber after melt kneading and drying at a cooling rate of 40°C/hr or higher.

In the production method of the acrylic rubber veil of the present invention, it is preferable to wash, dehydrate, and dry the hydrous crumb having a particle diameter range of 710 μm to 6.7 mm in a ratio of 50% by weight or more.

In the production method of the acrylic rubber veil of the present invention, it is preferable that the cutting temperature of the sheet-shaped dry rubber in the cutting step is 60°C or less.

In the production method of the acrylic rubber veil of the present invention, it is preferable that the lamination temperature of the sheet-shaped dry rubber in the cooling step is 30°C or higher.

According to the present invention, there is also provided a rubber composition comprising a rubber component including the acrylic rubber veil, a filler, and a crosslinking agent.

In the rubber composition of the present invention, it is preferable that the filler is a reinforcing filler. Further, in the rubber composition of the present invention, it is preferable that the filler is carbon black. Further, in the rubber composition of the present invention, it is preferable that the filler is a silica type.

In the rubber composition of the present invention, it is preferable that the crosslinking agent is an organic crosslinking agent. Further, in the rubber composition of the present invention, it is preferable that the crosslinking agent is a polyvalent compound. In addition, in the rubber composition of the present invention, it is preferable that the crosslinking agent is an ionic crosslinkable compound. Furthermore, in the rubber composition of the present invention, it is preferable that the crosslinking agent is an ionic crosslinkable organic compound. Furthermore, in the rubber composition of the present invention, it is preferable that the crosslinking agent is a polyvalent ion organic compound.

In the rubber composition of the present invention, the ion of the ion crosslinkable compound, ion crosslinkable organic compound or polyvalent ionic organic compound as the crosslinking agent is selected from the group consisting of an amino group, an epoxy group, a carboxyl group, and a thiol group, and has an ionic reactivity of at least one kind It is preferable to originate.

In the rubber composition of the present invention, the crosslinking agent is preferably at least one polyvalent ionic compound selected from the group consisting of polyvalent amine compounds, polyvalent epoxy compounds, polyvalent carboxylic acid compounds, and polyvalent thiol compounds.

In the rubber composition of the present invention, the content of the crosslinking agent is preferably in the range of 0.001 to 20 parts by weight based on 100 parts by weight of the rubber component.

The rubber composition of the present invention preferably further contains an anti-aging agent. In the rubber composition of the present invention, it is preferable that the anti-aging agent is an amine-based anti-aging agent.

According to the present invention, there is also provided a method for producing a rubber composition in which a crosslinking agent is mixed after mixing a rubber component containing the above acrylic rubber, a filler, and, if necessary, an antiaging agent.

According to the present invention, a crosslinked rubber product obtained by crosslinking the above rubber composition is further provided. In the crosslinked rubber product of the present invention, crosslinking of the rubber composition is preferably performed after molding. Further, in the crosslinked rubber product of the present invention, it is preferable that the crosslinking of the rubber composition is performed by primary crosslinking and secondary crosslinking.

According to the present invention, an acrylic rubber veil having highly excellent Banbury processability, strength characteristics, compression set resistance, and water resistance, an efficient manufacturing method thereof, a high-quality rubber composition including the acrylic rubber veil, and a crosslinked rubber crosslinked product thereof Provided.

1 is a diagram schematically showing an example of an acrylic rubber manufacturing system used for manufacturing an acrylic rubber veil according to an embodiment of the present invention.
Figure 2 is a view showing the configuration of the screw type extruder of Figure 1.
FIG. 3 is a diagram showing the configuration of a transport type cooling device used as the cooling device in FIG. 1 .

The acrylic rubber veil of the present invention has an ionic reactive group, and is made of an acrylic rubber having an ionic reactive group, the gel amount of the methyl ethyl ketone insoluble content is 15% by weight or less, and all values randomly measured at 20 points are (average value ± 5) It is within the range of % by weight, the pH is 6 or less, the amount of ash is 0.0005% by weight or more and 0.2% by weight or less, and the total amount of sodium, sulfur, calcium, magnesium, and phosphorus in the ash is 90% by weight or more.

<Ion reactive group>

The acrylic rubber veil of the present invention is characterized by having an ion-reactive group, and is involved in a crosslinking reaction to improve compression set resistance. The ionic reactive group is not particularly limited as long as it is a functional group involved in ionic reaction, and is appropriately selected depending on the purpose of use. Usually, when it is at least one functional group (reactive group) selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, acrylic It is suitable because it can highly improve the compression permanent deformation resistance of rubber veils.

The content of the ionic reactive group in the acrylic rubber veil of the present invention is not particularly limited and may be appropriately selected according to the purpose of use, but is usually 0.001 to 5% by weight, preferably 0.01 to 3% by weight of the ionic reactive group itself. % by weight, more preferably 0.05 to 1% by weight, particularly preferably 0.1 to 0.5% by weight, the processability and crosslinkability of the acrylic rubber veil, and strength characteristics when made into a crosslinked product, compression set resistance Characteristics, such as oil resistance, cold resistance, and water resistance, are highly balanced, so they are suitable.

The acrylic rubber veil having an ion-reactive group of the present invention may be obtained by introducing an ion-reactive group such as a carboxyl group, an epoxy group, or a chlorine atom into an acrylic rubber by a post-reaction, but is preferably an acrylic rubber obtained by copolymerizing an ion-reactive group-containing monomer. It is a veil made of acrylic rubber.

<Monomer component>

The monomer component of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited and may be appropriately selected depending on the purpose of use, and is at least selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters. When it is composed of one type of (meth)acrylic acid ester, an ionic reactive group-containing monomer, and other monomers that can be copolymerized as needed, properties such as short-time crosslinking, compression set resistance, weather resistance, heat resistance, and oil resistance are exhibited. It is highly balanced and suitable. On the other hand, in the present invention, "(meth)acrylic acid ester" is used as a general term for esters of acrylic acid and/or methacrylic acid.

The (meth)acrylic acid alkyl ester is not particularly limited, but is usually a (meth)acrylic acid alkyl ester having an alkyl group of 1 to 12 carbon atoms, preferably a (meth)acrylic acid alkyl ester having an alkyl group of 1 to 8 carbon atoms. Preferably, (meth)acrylic acid alkyl ester having an alkyl group having 2 to 6 carbon atoms is used.

Specific examples of (meth)acrylic acid alkyl esters include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, (meth) isobutyl acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and cyclohexyl (meth)acrylate; among these, ethyl (meth)acrylate and n-butyl (meth)acrylate are preferred. And, ethyl acrylate and n-butyl acrylate are more preferable.

The (meth)acrylic acid alkoxyalkyl ester is not particularly limited, but is usually a (meth)acrylic acid alkoxyalkyl ester having an alkoxyalkyl group having 2 to 12 carbon atoms, preferably a (meth)acrylic acid alkoxy having an alkoxyalkyl group having 2 to 8 carbon atoms. An alkyl ester, more preferably a (meth)acrylic acid alkoxyalkyl ester having an alkoxyalkyl group having 2 to 6 carbon atoms is used.

Specific examples of (meth)acrylic acid alkoxyalkyl esters include methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, methoxypropyl (meth)acrylate, methoxybutyl (meth)acrylate, and (meth)acrylic acid. Toxymethyl, ethoxyethyl (meth)acrylate, propoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, and the like are exemplified. Among these, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, etc. are preferable, and methoxyethyl acrylate and ethoxyethyl acrylate are more preferable.

At least one (meth)acrylic acid ester selected from the group consisting of these (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters is used alone or in combination of two or more, respectively, in all monomer components Their ratio is usually 50 to 99.99% by weight, preferably 62 to 99.95% by weight, more preferably 74 to 99.9% by weight, particularly preferably 80 to 99.5% by weight, and most preferably 87 to 99% by weight. When in the range of , the weather resistance, heat resistance, and oil resistance of the acrylic rubber veil are highly excellent and suitable.

The ion-reactive group-containing monomer is not particularly limited as long as it is a functional group involved in ionic reaction, and is appropriately selected depending on the purpose of use, but usually at least one functional group (reactive group) selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom. A monomer having a carboxyl group and an epoxy group, preferably a monomer having a carboxyl group and an epoxy group, more preferably a monomer having a carboxyl group can greatly improve the short-time crosslinking property of the acrylic rubber veil and the compression set resistance or water resistance of the crosslinked product. It is suitable.

Although there is no particular limitation as a monomer which has a carboxyl group, Ethylenically unsaturated carboxylic acid can be used suitably. Examples of the ethylenically unsaturated carboxylic acids include ethylenically unsaturated monocarboxylic acids, ethylenically unsaturated dicarboxylic acids, and ethylenically unsaturated dicarboxylic acid monoesters. Among these, particularly ethylenically unsaturated Dicarboxylic acid monoesters are preferable because they can further enhance the compression set resistance when acrylic rubber veils are made of cross-linked rubber.

As the ethylenically unsaturated monocarboxylic acid, there is no particular limitation, but an ethylenically unsaturated monocarboxylic acid having 3 to 12 carbon atoms is preferable, and examples thereof include acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid, and cinnamic acid. etc. can be mentioned.

As the ethylenically unsaturated dicarboxylic acid, there is no particular limitation, but an ethylenically unsaturated dicarboxylic acid having 4 to 12 carbon atoms is preferable. For example, fumaric acid, butenedioic acid such as maleic acid, itaconic acid, citraconic acid etc. can be mentioned. On the other hand, ethylenically unsaturated dicarboxylic acids include those existing as an anhydride.

The ethylenically unsaturated dicarboxylic acid monoester is not particularly limited, but is usually an ethylenically unsaturated dicarboxylic acid having 4 to 12 carbon atoms and an alkyl monoester having 1 to 12 carbon atoms, preferably ethylene having 4 to 6 carbon atoms. C2-C8 alkyl monoesters with sexually unsaturated dicarboxylic acids, more preferably C2-C6 alkyl monoesters of C4 butenedioic acid.

Specific examples of the ethylenically unsaturated dicarboxylic acid monoester include monomethyl fumarate, monoethyl fumarate, monon-butyl fumarate, monomethyl maleate, monoethyl maleate, monon-butyl maleate, and monocyclopentyl fumarate. Butenedioic acid monoalkyl esters such as monocyclohexyl fumarate, monocyclohexenyl fumarate, monocyclopentyl maleate, and monocyclohexyl maleate; itaconic acid monoalkyl esters such as monomethyl itaconate, monoethyl itaconate, monon-butyl itaconate, and monocyclohexyl itaconate; These etc. are mentioned, Among these, mono n-butyl fumarate and mono n-butyl maleate are preferable, and mono n-butyl fumarate is especially preferable.

Examples of the monomer having an epoxy group include epoxy group-containing (meth)acrylic acid esters such as glycidyl (meth)acrylate; epoxy group-containing vinyl ethers such as allyl glycidyl ether and vinyl glycidyl ether; etc. can be mentioned.

The monomer having a chlorine atom is not particularly limited, and examples thereof include unsaturated alcohol esters of chlorine atom-containing saturated carboxylic acids, (meth)acrylic acid chloroalkyl esters, (meth)acrylic acid chloroacyloxyalkyl esters, and (meth)acrylic acid chloroalkyl esters. ) acrylic acid (chloroacetylcarbamoyloxy)alkyl esters, chlorine atom-containing unsaturated ethers, chlorine atom-containing unsaturated ketones, chloromethyl group-containing aromatic vinyl compounds, chlorine atom-containing unsaturated amides, chloroacetyl group-containing unsaturated monomers, and the like.

Specific examples of the unsaturated alcohol ester of a chlorine atom-containing saturated carboxylic acid include vinyl chloroacetate, vinyl 2-chloropropionate, and allyl chloroacetate. Specific examples of the (meth)acrylic acid chloroalkyl ester include chloromethyl (meth)acrylate, 1-chloroethyl (meth)acrylate, 2-chloroethyl (meth)acrylate, 1,2-dichloroethyl (meth)acrylate, ( 2-chloropropyl (meth)acrylate, 3-chloropropyl (meth)acrylate, and 2,3-dichloropropyl (meth)acrylate. Specific examples of (meth)acrylic acid chloroacyloxyalkyl esters include (meth)acrylic acid 2-(chloroacetoxy)ethyl, (meth)acrylic acid 2-(chloroacetoxy)propyl, (meth)acrylic acid 3-(chloroacetoxy) Toxy)propyl, (meth)acrylic acid 3-(hydroxychloroacetoxy)propyl, etc. are mentioned. Examples of (meth)acrylic acid (chloroacetylcarbamoyloxy)alkyl esters include (meth)acrylic acid 2-(chloroacetylcarbamoyloxy)ethyl, (meth)acrylic acid 3-(chloroacetylcarbamoyloxy) ) profile, etc. Specific examples of the chlorine atom-containing unsaturated ether include chloromethyl vinyl ether, 2-chloroethyl vinyl ether, 3-chloropropyl vinyl ether, 2-chloroethyl allyl ether, and 3-chloropropyl allyl ether. Specific examples of the chlorine atom-containing unsaturated ketone include 2-chloroethyl vinyl ketone, 3-chloropropyl vinyl ketone, and 2-chloroethyl allyl ketone. Specific examples of the chloromethyl group-containing aromatic vinyl compound include p-chloromethyl styrene, m-chloromethyl styrene, o-chloromethyl styrene, and p-chloromethyl-α-methyl styrene. Specific examples of the chlorine atom-containing unsaturated amide include N-chloromethyl (meth)acrylamide. Further, specific examples of the chloroacetyl group-containing unsaturated monomer include 3-(hydroxychloroacetoxy)propyl allyl ether, p-vinylbenzylchloroacetic acid ester and the like.

These ion-reactive group-containing monomers are used individually or in combination of two or more, and the ratio in all monomer components is usually 0.01 to 10% by weight, preferably 0.05 to 8% by weight, more preferably 0.1 to 6% by weight. %, particularly preferably in the range of 0.5 to 5% by weight, most preferably in the range of 1 to 3% by weight.

There is no particular limitation as long as the monomers other than the above (abbreviated as "other monomers" in the present invention) that can be used together with the above monomers as needed are copolymerizable with the above monomers. For example, styrene, α- aromatic vinyls such as methyl styrene and divinylbenzene; ethylenically unsaturated nitriles such as acrylonitrile and methacrylonitrile; acrylamide-based monomers such as acrylamide and methacrylamide; Olefin type monomers, such as ethylene, propylene, vinyl acetate, ethyl vinyl ether, and butyl vinyl ether, etc. are mentioned.

These other monomers are used individually or in combination of two or more, and the ratio in all monomer components is usually 0 to 40% by weight, preferably 0 to 30% by weight, more preferably 0 to 20% by weight. , particularly preferably in the range of 0 to 15% by weight, most preferably in the range of 0 to 10% by weight.

<Acrylic Rubber>

The acrylic rubber constituting the acrylic rubber veil of the present invention is characterized by having the above ion-reactive group, and is preferably composed of the above monomer components, or has a weight average molecular weight (Mw), number average molecular weight (Mn), and The ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw/Mn) and the like are within a specific range.

The acrylic rubber monomer constituting the acrylic rubber veil of the present invention is at least one (meth)acrylic acid ester selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters, and an ionic reactive group-containing monomer. , and bonding units from other monomers included as necessary, and each ratio in the acrylic rubber is at least one selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters. The bonding unit derived from (meth)acrylic acid ester is usually 50 to 99.99% by weight, preferably 62 to 99.95% by weight, more preferably 74 to 99.9% by weight, particularly preferably 80 to 99.5% by weight, most preferably is in the range of 87 to 99% by weight, and the bonding unit derived from the ionic reactive group-containing monomer is usually 0.01 to 10% by weight, preferably 0.05 to 8% by weight, more preferably 0.1 to 6% by weight, particularly preferably is in the range of 0.5 to 5% by weight, most preferably 1 to 3% by weight, and the bonding unit derived from other monomers is usually 0 to 40% by weight, preferably 0 to 30% by weight, more preferably 0 to 20% by weight, particularly preferably 0 to 15% by weight, most preferably 0 to 10% by weight. When the monomer composition of acrylic rubber is within this range, properties such as short-time crosslinking property, compression set resistance, weather resistance, heat resistance, and oil resistance of the acrylic rubber veil are highly balanced and suitable.

The number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited, but is usually 10,000 to 3,000,000, preferably 15,000 to 2,500,000, more preferably 20,000 to 2,000,000. is the range of If the number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil is excessively small, strength characteristics and compression set resistance are deteriorated. In addition, the number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil of the present invention is usually 300,000 to 1.5 million, preferably 350,000 to 1.3 million, more preferably 400,000 to 1.1 million, particularly preferably In the range of 500,000 to 1,000,000, most preferably 550,000 to 750,000, Banbury workability, injection moldability, strength characteristics, and compression set resistance of the acrylic rubber veil are highly balanced and suitable.

The weight average molecular weight (Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited, but is usually 100,000 to 10,000,000, preferably 200,000 to 8,000,000, more preferably 250,000 to 750,000. 10,000, particularly preferably 300,000 to 6,000,000, most preferably 500,000 to 5,500,000. If the weight average molecular weight (Mw) of the acrylic rubber constituting the acrylic rubber veil is excessively small, the strength characteristics and compression set resistance of the acrylic rubber veil are deteriorated. In addition, the weight average molecular weight (Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is usually 1 million to 5 million, preferably 1.1 million to 4 million, more preferably 1.2 million to 3 million, particularly preferably In the range of 1.5 million to 2.5 million, most preferably 1.6 million to 2.2 million, the Banbury workability, injection moldability, strength characteristics, and compression set resistance of the acrylic rubber veil are highly balanced and suitable.

The z-average molecular weight (Mz) of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited and may be appropriately selected depending on the purpose of use, but is usually 1.5 million or more, preferably 2 million or more, more preferably 250 10,000 or more, particularly preferably 3,000,000 or more. The z-average molecular weight (Mz) of the acrylic rubber constituting the acrylic rubber veil of the present invention is also usually 1.5 to 6 million, preferably 1.8 to 5.5 million, more preferably 2 to 5 million, particularly preferably Preferably in the range of 2.2 million to 4.5 million, most preferably 2.5 million to 4 million, the injection moldability, Banbury processability, strength characteristics, and compression set resistance of the acrylic rubber veil are highly balanced and suitable.

The ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited, but is usually 1 to 25, preferably 1.1 to 20. , more preferably from 1.2 to 15, particularly preferably from 1.3 to 10. If the ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil is excessively small, the strength characteristics or compression set resistance of the acrylic rubber veil are deteriorated, Conversely, if it is excessively large, Banbury workability is poor, which is not preferable. The ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil of the present invention (Mw/Mn) is usually 1.5 to 3, preferably 1.8 to 2.7, more preferably Preferably in the range of 2 to 2.6, particularly preferably 2.2 to 2.6, the injection moldability and Banbury workability of the acrylic rubber veil, the strength characteristics and compression set resistance characteristics when crosslinked are highly balanced and suitable. In particular, when the ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of the acrylic rubber constituting the acrylic rubber veil of the present invention is within this range, the shape forming property of the acrylic rubber veil is injection moldable. , fusibility, and releasability are remarkably excellent, and the strength characteristics and compression set resistance characteristics of a cross-linked product are highly balanced and suitable.

The molecular weight distribution centering on the high molecular weight region of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited, but is determined by the ratio (Mz/Mw) of the z average molecular weight (Mz) to the weight average molecular weight (Mw). , usually 1.3 or more, preferably 1.4 or more, more preferably 1.5 or more, particularly preferably 1.6 or more, most preferably 1.7 or more, release properties and shape when the weight average molecular weight (Mw) becomes excessively small It is suitable because deterioration of formability (burr generation) can be prevented. The molecular weight distribution (Mz/Mw) centered on the high molecular weight region of the acrylic rubber constituting the acrylic rubber veil of the present invention is usually 4 or less, preferably 3 or less, more preferably 2.5 or less, particularly preferably When is 2.2 or less, most preferably 2 or less, deterioration in shape forming property (shape insufficiency) or fusibility when the weight average molecular weight (Mw) becomes excessively large can be prevented, and is suitable. The molecular weight distribution (Mz/Mw) centering on the high molecular weight region of the acrylic rubber constituting the acrylic rubber veil of the present invention is usually 1.3 to 3, preferably 1.4 to 2.5, more preferably 1.5 to 2.2, Particularly preferably in the range of 1.6 to 2, most preferably 1.7 to 1.9, it is suitable because the injection moldability and Banbury processability can be highly improved without impairing the strength characteristics of the acrylic rubber veil.

The measurement of the molecular weight (Mn, Mw, Mz) and molecular weight distribution (Mw/Mn, Mz/Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited, but the absolute molecular weight by the GPC-MALS method ( Mn, Mw, Mz) and absolute molecular weight distribution (Mw/Mn, Mz/Mw), each characteristic is obtained more accurately and is suitable.

The measurement solvent of the GPC-MALS method for measuring the molecular weight (Mn, Mw, Mz) and molecular weight distribution (Mw/Mn, Mz/Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is the acrylic rubber veil of the present invention. There is no particular limitation as long as it can be measured by dissolving, but a dimethylformamide solvent is suitable. The dimethylformamide-based solvent used is not particularly limited as long as it has dimethylformamide as a main component, but 100% dimethylformamide or a polar substance added to dimethylformamide can be used. The proportion of dimethylformamide in the dimethylformamide solvent is 90% by weight or more, preferably 95% by weight or more, and more preferably 97% by weight or more. The compound added to dimethylformamide is not particularly limited, but in the present invention, a solution in which lithium chloride is added to dimethylformamide at a concentration of 0.05 mol/L and 37% concentrated hydrochloric acid at a concentration of 0.01%, respectively, is suitable. .

The glass transition temperature (Tg) of the acrylic rubber constituting the acrylic rubber veil of the present invention may be appropriately selected depending on the purpose of use of the acrylic rubber, but is usually 20°C or less, preferably 10°C or less, and more preferably 0°C. When it is below, it is excellent in workability and cold resistance and is suitable. The lower limit of the glass transition temperature (Tg) of acrylic rubber is not particularly limited, but is usually -80°C or higher, preferably -60°C or higher, more preferably -40°C or higher. By setting the glass transition temperature above the lower limit, the oil resistance and heat resistance of the acrylic rubber veil can be improved, and by setting the glass transition temperature below the upper limit above, the workability, crosslinkability, and cold resistance of the acrylic rubber veil can be further improved.

<Acrylic rubber veil>

The acrylic rubber veil of the present invention is made of the above-mentioned acrylic rubber, and the gel amount of the methyl ethyl ketone insoluble component is 15% by weight or less, and all values randomly measured at 20 points are within the range of (average value ± 5)% by weight , pH is 6 or less, the amount of ash is 0.0005% by weight or more and 0.2% by weight or less, and the total amount of sodium, sulfur, calcium, magnesium, and phosphorus in the ash is 90% by weight or more.

The gel amount of the methyl ethyl ketone insoluble component of the acrylic rubber veil of the present invention is 15% by weight or less, preferably 13% by weight or less, more preferably 10% by weight or less, particularly preferably 7% by weight or less, most preferably When it is less than 5% by weight, workability and injection moldability at the time of kneading such as Banbury are highly improved and are suitable.

When the gel amount of the methyl ethyl ketone insoluble component of the acrylic rubber veil of the present invention is arbitrarily measured at 20 points, all 20 points fall within the range of (average value ± 5) weight%, preferably (average value ± 3) When all 20 points are within the range of weight%, there is no processability deviation, and various physical properties of the rubber composition or crosslinked rubber are stabilized and suitable. On the other hand, when the gel amount of the acrylic rubber veil is randomly measured at 20 points, all 20 points fall within the range of the average value ± 5, It means that all 20 points of gel amount are included, and for example, when the average value of the measured gel amount is 20% by weight, it means that all 20 points of measured value are within the range of 15 to 25% by weight.

The acrylic rubber veil of the present invention is highly balanced in Banbury workability and strength characteristics of the acrylic rubber veil and is suitable when the acrylic rubber is melt-kneaded and dried in a state in which water is substantially removed by a screw type twin screw extrusion dryer.

When the pH of the acrylic rubber veil of the present invention is in the range of 6 or less, preferably 2 to 6, more preferably 2.5 to 5.5, and most preferably 3 to 5, the storage stability of the acrylic rubber veil is highly improved and suitable for registration. do.

The lower limit of the ash content of the acrylic rubber veil of the present invention is 0.0001% by weight or more, preferably 0.0005% by weight or more, more preferably 0.001% by weight or more, particularly preferably 0.005% by weight or more, and most preferably 0.01% by weight. more than % When the ash content of the acrylic rubber veil is within this range, the metal adhesion of the rubber is reduced and workability is excellent, and the injection moldability and releasability are excellent, so it is suitable.

The upper limit of the ash content of the acrylic rubber veil of the present invention is 0.2% by weight or less, preferably 0.19% by weight or less, more preferably 0.18% by weight or less, particularly preferably 0.15% by weight or less, and most preferably 0.13% by weight or less. less than % When the ash content of the acrylic rubber veil is within this range, water resistance, storage stability, strength characteristics, processability, and compatibility of injection moldability are highly balanced and suitable.

When the acrylic rubber veil of the present invention is highly balanced in water resistance, storage stability, strength characteristics, processability, workability, and injection moldability and moldability, the amount of ash is usually 0.0001 to 0.3% by weight, preferably 0.0005 to 0.2% by weight. % by weight, more preferably 0.001 to 0.18% by weight, particularly preferably 0.005 to 0.15% by weight, most preferably 0.01 to 0.13% by weight.

When the total amount of sodium, magnesium, calcium, phosphorus, and sulfur in the ash of the acrylic rubber veil of the present invention is 90% by weight or more, preferably 93% by weight or more, more preferably 95% by weight or more, the water resistance of the acrylic rubber veil It is suitable for injection molding because it has highly improved fusibility and releasability.

The total amount of magnesium and phosphorus in the ash of the acrylic rubber veil of the present invention is not particularly limited and may be appropriately selected depending on the purpose of use, but is usually 30% by weight or more, preferably 50% by weight or more, more preferably 70% by weight or more. , particularly preferably 80% by weight or more, most preferably 90% by weight or more, the acrylic rubber veil is highly balanced in terms of water resistance, strength characteristics, compatibility and releasability of injection molding, and processability and is suitable.

The amount of magnesium in the ash of the acrylic rubber veil of the present invention is not particularly limited and is appropriately selected depending on the purpose of use, but is usually 10% by weight or more, preferably 15 to 60% by weight, more preferably 20 to 50% by weight, It is particularly preferably in the range of 25 to 45% by weight, most preferably 30 to 40% by weight.

The amount of phosphorus in the ash of the acrylic rubber veil of the present invention is not particularly limited and is appropriately selected depending on the purpose of use, but is usually 10% by weight or more, preferably 20 to 90% by weight, more preferably 30 to 80% by weight, particularly It is preferably in the range of 40 to 70% by weight, most preferably 50 to 60% by weight.

The ratio of magnesium to phosphorus in the ash content of the acrylic rubber veil of the present invention ([Mg]/[P]) is not particularly limited and may be appropriately selected depending on the purpose of use, but in terms of weight ratio, it is usually 0.4 to 2.5, preferably 0.45 to When in the range of 1.2, more preferably 0.45 to 1, particularly preferably 0.5 to 0.8, and most preferably 0.55 to 0.7, the acrylic rubber veil's water resistance, strength characteristics, injection molding compatibility and releaseability, and processability are highly balanced. become a good fit

Here, the ash in the acrylic rubber veil is mainly derived from the emulsifier used when emulsifying the monomer components and performing emulsion polymerization and the coagulant used when coagulating the emulsion polymerization solution. It changes not only by the conditions of the emulsion polymerization process and the solidification process, but also by various conditions of each subsequent process.

In order to achieve a high balance of water resistance, strength characteristics, meltability and releasability of injection molding, and processability of the acrylic rubber veil, an anionic emulsifier, a cationic emulsifier, or a nonionic emulsifier, which will be described later, is preferred as an emulsifier for emulsion polymerization of acrylic rubber, in particular. Preferably, it is appropriate to use an anionic emulsifier, more preferably a phosphoric acid ester salt or a sulfuric acid ester salt. The water resistance of the acrylic rubber veil is uniquely correlated with the amount of ash in the acrylic rubber and the total amount of sodium, magnesium, calcium, phosphorus, and sulfur in the ash. It is suitable because it can balance the convergence, releasability and workability of molding more highly.

In order to achieve a high balance of water resistance, strength characteristics, injection molding fusibility, releasability and processability of the acrylic rubber veil, it is particularly suitable to use a metal salt described later as a coagulant, preferably an alkali metal salt or a metal salt of Group 2 of the periodic table. The water resistance of acrylic rubber is uniquely correlated with the amount of ash in the acrylic rubber veil and the total amount of sodium, magnesium, calcium, phosphorus, and sulfur in the ash. It is more highly balanced and suitable for molding convergence, releasability and workability.

The complex viscosity ([η] 100°C) of the acrylic rubber veil of the present invention at 100°C is not particularly limited and may be appropriately selected depending on the purpose of use, but is usually 15,000 [Pa s] or less, preferably 1,000 to 1000. Processability in the range of 10,000 [Pa s], more preferably 2,000 to 8,000 [Pa s], particularly preferably 3,000 to 5,000 [Pa s], and most preferably 3,500 to 4,000 [Pa s] , excellent in oil resistance, injection moldability, and shape retention, making it suitable.

The ratio of the complex viscosity at 100°C ([η]100°C) and the complex viscosity at 60°C ([η]60°C) of the acrylic rubber veil of the present invention ([η]100°C/[η]60°C) ) is not particularly limited and may be appropriately selected depending on the purpose of use, but is usually 0.5 or more, preferably 0.6 or more, and more preferably 0.7 or more. The ratio of the complex viscosity at 100°C ([η]100°C) and the complex viscosity at 60°C ([η]60°C) of the acrylic rubber veil of the present invention ([η]100°C/[η]60°C) ) is also usually in the range of 0.5 to 0.99, preferably 0.55 to 0.95, more preferably 0.6 to 0.9, particularly preferably 0.65 to 0.85, and most preferably 0.7 to 0.8 in terms of workability, oil resistance, and shape Retention is highly balanced and suitable.

The specific gravity of the acrylic rubber veil of the present invention is not particularly limited, but is usually 0.7 or more, preferably 0.8 or more, more preferably 0.9 or more, particularly preferably 0.95 or more, and most preferably 1 or more. It is suitable because it is not internalized and has excellent storage stability. The specific gravity of the acrylic rubber veil of the present invention is also usually in the range of 0.7 to 1.6, preferably 0.8 to 1.5, more preferably 0.9 to 1.4, particularly preferably 0.95 to 1.3, and most preferably 1.0 to 1.2. Productivity, storage stability, and crosslinking property stability of the crosslinked product are highly balanced and suitable. When the specific gravity of the acrylic rubber veil is excessively small, it indicates a large amount of air in the acrylic rubber veil, and it is undesirable because it greatly affects storage stability including oxidative degradation and the like.

On the other hand, the specific gravity of the acrylic rubber of the present invention is obtained by dividing the mass by the capacity including voids, that is, by dividing the mass measured in air by the buoyancy, which is usually measured according to JIS K6268 Crosslinked Rubber - Method A of Density Measurement will be.

In addition, the acrylic rubber veil of the present invention is an acrylic rubber veil obtained by drying acrylic rubber under reduced pressure by means of a screw-type twin screw extrusion dryer, or by melting and extruding drying acrylic rubber under reduced pressure, and has characteristics of storage stability, injection moldability and strength characteristics. It is suitable because it is particularly excellent and highly balanced.

The water content of the acrylic rubber veil of the present invention is not particularly limited and is appropriately selected depending on the purpose of use, but is usually less than 1% by weight, preferably 0.8% by weight or less, more preferably 0.6% by weight or less, It is suitable because it has optimized vulcanization properties and highly improved properties such as heat resistance and water resistance.

The Mooney viscosity (ML ₁₊₄ , 100°C) of the acrylic rubber veil of the present invention is not particularly limited and may be appropriately selected depending on the purpose of use, but is usually 10 to 150, preferably 20 to 100, more preferably 25 In the range of ~ 70, the workability and strength characteristics of the acrylic rubber veil are highly balanced and suitable.

The size of the acrylic rubber veil of the present invention is not particularly limited and is appropriately selected depending on the purpose of use. The width is usually in the range of 100 to 800 mm, preferably 200 to 500 mm, more preferably 250 to 450 mm, and the length is usually 300 to 1,200 mm, preferably 400 to 1,000 mm, more preferably 500 to 800 mm, and the height (thickness) is usually 50 to 500 mm, preferably 100 to 300 mm, more preferably 150 to 250 mm It is appropriate to be in Also, the shape of the acrylic rubber veil of the present invention is not limited and is appropriately selected depending on the purpose of use of the acrylic rubber veil, but in many cases, a rectangular parallelepiped is suitable.

<Manufacturing method of acrylic rubber veil>

The method for producing the acrylic rubber veil of the present invention is not particularly limited, but includes, for example, at least one (meth)acrylic acid selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters. An emulsification step of emulsifying a monomer component composed of an ester, an ion-reactive group-containing monomer, and other monomers as necessary with water and an emulsifier;

An emulsion polymerization step of obtaining an emulsion polymerization solution by emulsion polymerization in the presence of a redox catalyst composed of a radical generator and a reducing agent;

A coagulation step of bringing the obtained emulsion polymerization liquid into contact with a coagulant to produce a hydrous crumb;

A cleaning step of cleaning the generated hydrous crumb;

The washed hydrous crumb is dehydrated to a moisture content of 1 to 40% by weight in a dewatering barrel using a screw-type twin-screw extrusion dryer having a dewatering barrel with a dehydration slit, a drying barrel under reduced pressure, and a die at the tip, and then to a drying barrel. A dehydration, drying, and molding step of drying to less than the weight percent and extruding a sheet-like dried rubber from a die;

A cooling step of cooling the extruded sheet-like dry rubber;

A cutting step of cutting the cooled sheet-like dry rubber;

Lamination step of laminating cut sheet-shaped dry rubber

It can be efficiently produced by a manufacturing method comprising a.

(Emulsification process)

In the emulsification step in the method for producing an acrylic rubber veil of the present invention, at least one (meth)acrylic acid ester selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters, an ion-reactive group This is a step of emulsifying a monomer component composed of a contained monomer and, if necessary, other monomers with water and an emulsifier.

(monomer component)

The monomer component used in the present invention is at least one (meth)acrylic acid ester selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters, an ionic reactive group-containing monomer, and, if necessary, copolymerization. It is made of possible other monomers, and is the same as the examples and preferred ranges of the monomer components already described. The usage amount of the monomer component is also as described above, and in emulsion polymerization, each monomer may be appropriately selected so as to have the above composition of the acrylic rubber constituting the acrylic rubber veil of the present invention.

(Emulsifier)

The emulsifier used in the present invention is not particularly limited, but examples thereof include anionic emulsifiers, cationic emulsifiers, and nonionic emulsifiers, preferably anionic emulsifiers.

The anionic emulsifier is not particularly limited, and examples thereof include fatty acid salts such as myristic acid, palmitic acid, oleic acid, and linolenic acid; Alkylbenzenesulfonic acid salts, such as sodium dodecylbenzenesulfonate; phosphoric acid ester salts such as sulfuric acid ester salts such as sodium lauryl sulfate and polyoxyalkylene alkyl ether phosphoric acid ester salts; Alkyl sulfosuccinate etc. are mentioned. Among these anionic emulsifiers, phosphoric acid ester salts and sulfuric acid ester salts are preferable, phosphoric acid ester salts are particularly preferable, and divalent phosphoric acid ester salts are most preferable. Releasability and workability can be highly balanced. In addition, as these phosphoric acid ester salts or sulfuric acid ester salts, preferably alkali metal salts of phosphoric acid esters or sulfuric acid esters, more preferably sodium salts of phosphoric acid esters or sulfuric acid esters, water resistance, strength characteristics, and mold of the obtained acrylic rubber veil Releasability and processability can be highly balanced and suitable.

The divalent phosphoric acid ester salt is not particularly limited as long as it can be used as an emulsifier in the emulsion polymerization reaction, but includes alkyloxypolyoxyalkylene phosphoric acid ester salts, alkylphenyloxypolyoxyalkylene phosphoric acid ester salts, etc. Among these, metal salts thereof are preferred, alkali metal salts thereof are more preferred, and sodium salts thereof are most preferred.

Examples of the alkyloxypolyoxyalkylene phosphate ester salts include alkyloxypolyoxyethylene phosphate ester salts and alkyloxypolyoxypropylene phosphate ester salts. Among these, alkyloxypolyoxyethylene phosphate esters Salt is preferred.

Specific examples of the alkyloxypolyoxyethylene phosphate ester salt include octyloxydioxyethylene phosphate ester, octyloxytrioxyethylene phosphate ester, octyloxytetraoxyethylene phosphate ester, decyloxytetraoxyethylene phosphate ester, dodecyloxytetraoxy Ethylene Phosphate Ester, Tridecyloxytetraoxyethylene Phosphate Ester, Tetradecyloxytetraoxyethylene Phosphate Ester, Hexadecyloxytetraoxyethylene Phosphate Ester, Octadecyloxytetraoxyethylene Phosphate Ester, Octyloxypentaoxyethylene Phosphate Ester, Decyloxy Pentaoxyethylene Phosphate Ester, Dodecyloxypentaoxyethylene Phosphate Ester, Tridecyloxypentaoxyethylene Phosphate Ester, Tetradecyloxypentaoxyethylene Phosphate Ester, Hexadecyloxypentaoxyethylene Phosphate Ester, Octadecyloxypentaoxyethylene Phosphate Ester , octyloxyhexaoxyethylene phosphate ester, decyloxyhexaoxyethylene phosphate ester, dodecyloxyhexaoxyethylene phosphate ester, tridecyloxyhexaoxyethylene phosphate ester, tetradecyloxyhexaoxyethylene phosphate ester, hexadecyloxyhexaoxyethylene Phosphoric acid ester, octadecyloxyhexaoxyethylene phosphate ester, octyloxyoctaoxyethylene phosphate ester, decyloxyoctaoxyethylene phosphate ester, dodecyloxyoctaoxyethylene phosphate ester, tridecyloxyoctaoxyethylene phosphate ester, tetradecyloxyocta and metal salts such as oxyethylene phosphate ester, hexadecyloxyoctaoxyethylene phosphate ester, and octadecyloxyoctaoxyethylene phosphate ester. Among these, alkali metal salts thereof, particularly sodium salts, are suitable.

Specific examples of the alkyloxypolyoxypropylene phosphate ester salt include octyloxydioxypropylene phosphate ester, octyloxytrioxypropylene phosphate ester, octyloxytetraoxypropylene phosphate ester, decyloxytetraoxypropylene phosphate ester, dodecyloxytetraoxy Propylene phosphate ester, tridecyloxytetraoxypropylene phosphate ester, tetradecyloxytetraoxypropylene phosphate ester, hexadecyloxytetraoxypropylene phosphate ester, octadecyloxytetraoxypropylene phosphate ester, octyloxypentaoxypropylene phosphate ester, decyloxy Pentaoxypropylene Phosphate, Dodecyloxypentaoxypropylene Phosphate, Tridecyloxypentaoxypropylene Phosphate, Tetradecyloxypentaoxypropylene Phosphate, Hexadecyloxypentaoxypropylene Phosphate, Octadecyloxypentaoxypropylene Phosphate Ester , octyloxyhexaoxypropylene phosphate ester, decyloxyhexaoxypropylene phosphate ester, dodecyloxyhexaoxypropylene phosphate ester, tridecyloxyhexaoxypropylene phosphate ester, tetradecyloxyhexaoxypropylene phosphate ester, hexadecyloxyhexaoxypropylene Phosphate ester, octadecyloxyhexaoxypropylene phosphate ester, octyloxyoctaoxypropylene phosphate ester, decyloxyoctaoxypropylene phosphate ester, dodecyloxyoctaoxypropylene phosphate ester, tridecyloxyoctaoxypropylene phosphate ester, tetradecyloxyocta oxypropylene phosphate esters, hexadecyloxyoctaoxypropylene phosphate esters, octadecyloxyoctaoxypropylene phosphate esters, and metal salts thereof; among these, alkali metal salts thereof, particularly sodium salts, are suitable.

Specific examples of the alkylphenyloxypolyoxyalkylene phosphate ester salt include an alkylphenyloxypolyoxyethylene phosphate ester salt, an alkylphenyloxypolyoxypropylene phosphate ester salt, and the like, and among these, an alkylphenyloxypolyoxyethylene phosphate salt Ester salts are preferred.

Specific examples of the alkylphenyloxypolyoxyethylene phosphate ester include methylphenyloxytetraoxyethylene phosphate ester, ethylphenyloxytetraoxyethylene phosphate ester, butylphenyloxytetraoxyethylene phosphate ester, hexylphenyloxytetraoxyethylene phosphate ester, and nonyl. Phenyloxytetraoxyethylene phosphate ester, dodecylphenyloxytetraoxyethylene phosphate ester, octadecyloxytetraoxyethylene phosphate ester, methylphenyloxypentaoxyethylene phosphate ester, ethylphenyloxypentaoxyethylene phosphate ester, butylphenyloxypentaoxyethylene Phosphoric Acid Ester, Hexylphenyloxypentaoxyethylene Phosphate Ester, Nonylphenyloxypentaoxyethylene Phosphate Ester, Dodecylphenyloxypentaoxyethylene Phosphate Ester, Methylphenyloxyhexaoxyethylene Phosphate Ester, Ethylphenyloxyhexaoxyethylene Phosphate Ester, Butylphenyl Oxyhexaoxyethylene Phosphate Ester, Hexylphenyloxyhexaoxyethylene Phosphate Ester, Nonylphenyloxyhexaoxyethylene Phosphate Ester, Dodecylphenyloxyhexaoxyethylene Phosphate Ester, Methylphenyloxyhexaoxyethylene Phosphate Ester, Ethylphenyloxyoctaoxyethylene Phosphate metal salts such as esters, butylphenyloxyoctaoxyethylene phosphate esters, hexylphenyloxyoctaoxyethylene phosphate esters, nonylphenyloxyoctaoxyethylene phosphate esters, and dodecylphenyloxyoctaoxyethylene phosphate esters; Alkali metal salts, especially sodium salts, are suitable.

Specific examples of the alkylphenyloxypolyoxypropylene phosphate ester include methylphenyloxytetraoxypropylene phosphate ester, ethylphenyloxytetraoxypropylene phosphate ester, butylphenyloxytetraoxypropylene phosphate ester, hexylphenyloxytetraoxypropylene phosphate ester, and nonyl. Phenyloxytetraoxypropylene Phosphate Ester, Dodecylphenyloxytetraoxypropylene Phosphate Ester, Methylphenyloxypentaoxypropylene Phosphate Ester, Ethylphenyloxypentaoxypropylene Phosphate Ester, Butylphenyloxypentaoxypropylene Phosphate Ester, Hexylphenyloxypentaoxypropylene Phosphoric Acid Ester, Nonylphenyloxypentaoxypropylene Phosphate Ester, Dodecylphenyloxypentaoxypropylene Phosphate Ester, Methylphenyloxyhexaoxypropylene Phosphate Ester, Ethylphenyloxyhexaoxypropylene Phosphate Ester, Butylphenyloxyhexaoxypropylene Phosphate Ester, Hexylphenyl Oxyhexaoxypropylene Phosphate, Nonylphenyloxyhexaoxypropylene Phosphate, Dodecylphenyloxyhexaoxypropylene Phosphate, Methylphenyloxyoctaoxypropylene Phosphate, Ethylphenyloxyoctaoxypropylene Phosphate, Butylphenyloxyoctaoxypropylene Phosphate metal salts such as esters, hexylphenyloxyoctaoxypropylene phosphate esters, nonylphenyloxyoctaoxypropylene phosphate esters, and dodecylphenyloxyoctaoxypropylene phosphate esters; among these, alkali metal salts thereof, particularly sodium salts, are suitable. .

As the phosphoric acid ester salt, a monovalent phosphoric acid ester salt such as di(alkyloxypolyoxyalkylene) phosphoric acid ester sodium salt can be used alone or in combination with a divalent phosphoric acid ester salt.

Examples of the sulfuric acid ester salt include sodium lauryl sulfate, potassium lauryl sulfate, ammonium lauryl sulfate, sodium myristyl sulfate, sodium polyoxyethylene alkyl sulfate, and sodium polyoxyethylene alkyl aryl sulfate. Sodium lauryl sulfate is preferred.

Examples of the cationic emulsifier include alkyltrimethylammonium chloride, dialkylammonium chloride, and benzylammonium chloride.

Examples of the nonionic emulsifier include polyoxyalkylene fatty acid esters such as polyoxyethylene stearic acid ester; polyoxyalkylene alkyl ethers such as polyoxyethylene dodecyl ether; polyoxyalkylene alkylphenol ethers such as polyoxyethylene nonylphenyl ether; Polyoxyethylene sorbitan alkyl ester etc. are mentioned, Polyoxyalkylene alkyl ether and polyoxyalkylene alkyl phenol ether are preferable, and polyoxyethylene alkyl ether and polyoxyethylene alkyl phenol ether are more preferable.

These emulsifiers can be used individually or in combination of two or more, and the amount used is usually 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the monomer components. is in the range of 1 to 3 parts by weight.

The mixing method (mixing method) of the monomer component, water, and emulsifier may follow a conventional method, and examples thereof include a method of stirring the monomer, emulsifier, and water using an agitator such as a homogenizer or a disk turbine. can The amount of water used is usually 1 to 1000 parts by weight, preferably 5 to 500 parts by weight, more preferably 4 to 300 parts by weight, particularly preferably 3 to 150 parts by weight, most preferably 3 to 150 parts by weight, based on 100 parts by weight of the monomer components. Preferably it is in the range of 20 to 80 parts by weight.

(emulsion polymerization process)

In the emulsion polymerization step in the method for producing an acrylic rubber veil of the present invention, polymerization is initiated in the presence of a redox catalyst composed of a radical generating agent and a reducing agent, and a chain transfer agent is added batchwise in batches during the polymerization to continue polymerization, followed by emulsion polymerization. It is the process of obtaining liquid.

(radical generating agent)

The polymerization catalyst used in the present invention is characterized by using a redox catalyst composed of a radical generator and a reducing agent, and is suitable because it can highly improve the Banbury workability and strength characteristics of the obtained acrylic rubber veil. In addition, by using an organic radical generator as a radical generator, the injection moldability of the manufactured acrylic rubber veil can be further improved, so it is suitable.

The organic radical generator is not particularly limited as long as it is usually used in emulsion polymerization, and examples thereof include organic peroxides and azo compounds.

The organic peroxide is not particularly limited as long as it is a known peroxide used in emulsion polymerization, and examples thereof include 2,2-di(4,4-di-(t-butylperoxy)cyclohexyl)propane, 1-di- (t-hexylperoxy)cyclohexane, 1,1-di-(t-butylperoxy)cyclohexane, 4,4-di-(t-butylperoxy)valeric acid n-butyl, 2,2-di -(t-butylperoxy)butane, t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide, benzoyl peroxide, 1,1,3,3-tetra Ethylbutyl hydroperoxide, t-butylcumyl peroxide, di-t-butyl peroxide, di-t-hexyl peroxide, di(2-t-butylperoxyisopropyl)benzene, dicumyl peroxide, diisobuty Rel peroxide, di(3,5,5-trimethylhexanoyl) peroxide, dilauroyl peroxide, disuccinic acid peroxide, dibenzoyl peroxide, di(3-methylbenzoyl)peroxide, benzoyl(3-methylbenzoyl ) Peroxide, diisobutyrylperoxydicarbonate, di-n-propylperoxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, di-sec-butylperoxydicarbonate, 1,1,3,3-tetra Methylbutylperoxyneodecanate, t-hexylperoxypivalate, t-butylperoxyneodecanate, t-hexylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl-2,5 -Di(2-ethylhexanoylperoxy)hexane, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanate, t-hexylperoxy-2-ethylhexanate, t-butylperoxy -3,5,5-trimethylhexanate, t-hexylperoxyisopropylmonocarbonate, t-butylperoxyisopropylmonocarbonate, t-butylperoxy-2-ethylhexylmonocarbonate, 2,5-dimethyl- 2,5-di(benzoylperoxy)hexane, t-butylperoxyacetate, t-hexylperoxybenzoate, t-butylperoxybenzoate, 2,5-dimethyl-2,5-di(t-butyl peroxy)hexane and the like, and among these, diisopropylbenzene hydroperoxide, cumene hydroperoxide, paramentane hydroperoxide, benzoyl peroxide and the like are preferable.

Examples of the azo compound include azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), and 2,2'-azobis[2-(2-imidazoline-2). -yl) propane, 2,2'-azobis (propane-2-carboamidine), 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropanamide], 2,2' -Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}, 2,2'-azobis(1-imino-1-pyrrolidino-2 -methyl propane), and 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propanamide}.

These radical generators can be used individually or in combination of two or more types, and the amount used is usually 0.0001 to 5 parts by weight, preferably 0.0005 to 1 part by weight, based on 100 parts by weight of the monomer component. It is preferably in the range of 0.001 to 0.5 parts by weight.

(reducing agent)

The reducing agent used in the present invention is not particularly limited as long as it is usually used in emulsion polymerization, but preferably at least two reducing agents are used, and it is preferable to combine a metal ion compound in a reduced state with other reducing agents. It is suitable because the Banbury processability, injection moldability and strength characteristics of the resulting acrylic rubber veil can be more highly balanced.

Examples of the reduced metal ion compound include, but are not particularly limited to, ferrous sulfate, sodium hexamethylenediamine tetraacetate, cuprous naphthenate, and the like. Among these, ferrous sulfate is preferred. do. These metal ion compounds in a reduced state can be used individually or in combination of two or more, and the amount used is usually 0.000001 to 0.01 part by weight, preferably 0.00001 to 0.001, based on 100 parts by weight of the monomer component. Part by weight, more preferably in the range of 0.00005 to 0.0005 part by weight.

Reducing agents other than metal ion compounds in a reduced state used in the present invention are not particularly limited, and examples thereof include ascorbic acid or salts thereof such as ascorbic acid, sodium ascorbate, and potassium ascorbate; Erythorbic acid or its salt, such as erythorbic acid, sodium erythorbate, and potassium erythorbate; sulfinates such as sodium hydroxymethane sulfinate; sulfites of sodium sulfite, potassium sulfite, sodium bisulfite, aldehyde sodium bisulfite, potassium bisulfite; pyrosulfite salts such as sodium pyrosulfite, potassium pyrosulfite, sodium hydrogen bisulfite, and potassium hydrogen pyrosulfite; Thiosulfates, such as sodium thiosulfate and potassium thiosulfate; Phosphorous acid, sodium phosphite, potassium phosphite, sodium hydrogenphosphite, phosphorous acid of phosphorous acid or its salt; pyrophosphorous acids or salts thereof such as pyrophosphorous acid, sodium pyrophosphite, potassium pyrophosphite, sodium pyrophosphite, sodium hydrogen pyrophosphite, and potassium hydrogen pyrophosphite; Sodium formaldehyde sulfoxylate etc. are mentioned. Among these, ascorbic acid or a salt thereof, sodium formaldehyde sulfoxylate and the like are preferable, and ascorbic acid or a salt thereof is particularly preferable.

Reducing agents other than these metal ion compounds in a reduced state can be used individually or in combination of two or more, and the amount used is usually 0.001 to 1 part by weight, preferably 0.001 to 1 part by weight, based on 100 parts by weight of the monomer component. 0.005 to 0.5 parts by weight, more preferably 0.01 to 0.1 parts by weight.

A preferred combination of a metal ion compound in a reduced state and another reducing agent is a combination of ferrous sulfate and ascorbic acid or a salt thereof and/or sodium formaldehyde sulfoxylate, more preferably ferrous sulfate and ascorb It is an acid or a combination of its salts. The amount of ferrous sulfate used at this time is usually 0.000001 to 0.01 parts by weight, preferably 0.00001 to 0.001 parts by weight, more preferably 0.00005 to 0.0005 parts by weight, based on 100 parts by weight of the monomer components, and ascorbic acid or The amount of the salt and/or sodium formaldehyde sulfoxylate used is usually 0.001 to 1 part by weight, preferably 0.005 to 0.5 part by weight, more preferably 0.01 to 0.1 part by weight, based on 100 parts by weight of both components. .

The amount of water used in the emulsion polymerization reaction may be the amount used in emulsifying the monomer components, but is usually 10 to 1000 parts by weight, preferably 50 to 500 parts by weight, based on 100 parts by weight of the monomer components used for polymerization. More preferably, it is adjusted to be in the range of 80 to 400 parts by weight, most preferably 100 to 300 parts by weight.

The method of the emulsion polymerization reaction may be according to a conventional method, and any of a batch method, a semi-batch method, and a continuous method may be used. The polymerization temperature and polymerization time are not particularly limited and can be appropriately selected from the type of polymerization initiator to be used. The polymerization time is usually 0.5 to 100 hours, preferably 1 to 10 hours.

The emulsion polymerization reaction is an exothermic reaction, and if not controlled, the temperature rises and the polymerization reaction may be shortened. However, in the present invention, the emulsion polymerization reaction temperature is usually 35 ° C. or less, preferably 0 to 35 ° C., more preferably is controlled at 5 to 30 ° C., particularly preferably 10 to 25 ° C., the strength characteristics of the produced acrylic rubber veil and the processability during kneading such as Banbury are highly balanced and suitable.

(post-addition of chain transfer agent)

In the present invention, it is characterized in that the chain transfer agent is added batchwise and post-added during polymerization without initially adding, and by doing so, it is possible to produce an acrylic rubber in which a high-molecular-weight component and a low-molecular-weight component are separated, and also produced The Banbury processability of acrylic rubber veil, strength characteristics and injection moldability are highly balanced and suitable.

The chain transfer agent used is not particularly limited as long as it is usually used in emulsion polymerization, and for example, a mercaptan compound can be suitably used.

As the mercaptan compound, an alkyl mercaptan compound having usually 2 to 20 carbon atoms, preferably an alkyl mercaptan compound having 5 to 15 carbon atoms, and more preferably an alkyl mercaptan compound having 6 to 14 carbon atoms can be used.

The alkyl mercaptan compound may be any of n-alkyl mercaptan compounds, sec-alkyl mercaptan compounds, and t-alkyl mercaptan compounds, but preferably n-alkyl mercaptan compounds and t-alkyl mercaptan compounds. , more preferably an n-alkylmercaptan compound, since the effect of the chain transfer agent can be stably exhibited and the injection moldability of the produced acrylic rubber can be improved to a high degree, it is suitable.

Specific examples of the alkyl mercaptan compound include n-pentyl mercaptan, n-hexyl mercaptan, n-heptyl mercaptan, n-octyl mercaptan, n-decyl mercaptan, n-dodecyl mercaptan, and n-tri Decylmercaptan, n-tetradecylmercaptan, n-hexadecylmercaptan, n-octadecylmercaptan, sec-pentylmercaptan, sec-hexylmercaptan, sec-heptylmercaptan, sec-octylmercaptan, sec -decylmercaptan, sec-dodecylmercaptan, sec-tridecylmercaptan, sec-tetradecylmercaptan, sec-hexadecylmercaptan, sec-octadecylmercaptan, t-pentylmercaptan, t-hexylmer Captan, t-heptylmercaptan, t-octylmercaptan, t-decylmercaptan, t-dodecylmercaptan, t-tridecylmercaptan, t-tetradecylmercaptan, t-hexadecylmercaptan, t- Octadecyl mercaptan etc. are mentioned, Preferably they are n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, More preferably, they are n-octyl mercaptan and n-dodecyl mercaptan. .

These chain transfer agents can be used individually or in combination of 2 or more types, respectively. The amount of chain transfer agent used is not particularly limited, but is usually 0.0001 to 1 part by weight, preferably 0.0005 to 0.5 part by weight, more preferably 0.001 to 0.5 part by weight, particularly preferably 0.001 to 0.5 part by weight, based on 100 parts by weight of the monomer components. In the range of 0.005 to 0.1 parts by weight, most preferably 0.01 to 0.06 parts by weight, Banbury workability, strength characteristics and injection moldability of the acrylic rubber veil produced are highly balanced and suitable.

In the present invention, it is characterized in that the chain transfer agent is not added at the beginning of the polymerization but added batchwise during the polymerization, and the high molecular weight component and the low molecular weight component of the acrylic rubber to be produced are prepared, and the molecular weight distribution is set to a specific range. It is suitable because it can highly balance Banbury processability, strength characteristics and injection moldability of acrylic rubber veil.

The number of batchwise post-additions of the chain transfer agent is not particularly limited and is appropriately selected depending on the purpose of use, but is usually 1 to 5 times, preferably 2 to 4 times, more preferably 2 to 3 times, particularly preferably It is suitable because it can highly balance the Banbury workability, strength characteristics, and injection moldability of the acrylic rubber veil produced at the time of the second round.

The timing for starting the batchwise post-addition of the chain transfer agent is not particularly limited and is appropriately selected depending on the purpose of use, but is usually 20 minutes after the start of the polymerization, preferably 30 minutes after the start of the polymerization, more preferably 30 minutes after the start of the polymerization. After 30 to 200 minutes, particularly preferably 35 to 150 minutes after the start of polymerization, and most preferably 40 to 120 minutes after polymerization, Banbury workability, strength characteristics and injection moldability of the acrylic rubber veil produced can be highly balanced. It is suitable.

The addition amount per batch in the batchwise post-addition of the chain transfer agent is not particularly limited and is appropriately selected depending on the purpose of use, but is usually 0.00005 to 0.5 parts by weight, preferably 0.0001 to 0.1 parts by weight, based on 100 parts by weight of the monomer components. parts, more preferably 0.0005 to 0.05 parts by weight, particularly preferably 0.001 to 0.03 parts by weight, most preferably 0.002 to 0.02 parts by weight, Banbury processability, strength properties and injection moldability of the acrylic rubber veil produced It is suitable because it can be highly balanced.

After the addition of the chain transfer agent, there is no particular limitation, but the polymerization reaction can be continued for usually 30 minutes or more, preferably 45 minutes or more, and more preferably 1 hour or more, and then terminated.

(post-addition of reducing agent)

In the present invention, the reducing agent of the redox catalyst can be added post-added during polymerization, which is suitable because it can highly balance the strength characteristics and injection moldability of the acrylic rubber veil produced by doing so.

As the reducing agent added later during polymerization, the examples and preferred ranges of the reducing agent described above are the same. In the present invention, as the reducing agent to be added later, ascorbic acid or a salt thereof is suitable.

The amount of the reducing agent added later during polymerization is not particularly limited and may be appropriately selected depending on the purpose of use, but is usually 0.0001 to 1 part by weight, preferably 0.0005 to 0.5 part by weight, more preferably 0.0005 to 0.5 part by weight, based on 100 parts by weight of the monomer components. Preferably in the range of 0.001 to 0.5 parts by weight, particularly preferably in the range of 0.005 to 0.1 parts by weight, most preferably in the range of 0.01 to 0.05 parts by weight, the productivity of acrylic rubber production is excellent and the strength characteristics and injection moldability of the acrylic rubber veil produced It is suitable because it can be highly balanced.

The reducing agent added later during polymerization may be either continuous or batchwise, but is preferably batchwise. The number of times when the reducing agent is post-added batchwise during polymerization is not particularly limited, but is usually 1 to 5 times, preferably 1 to 3 times, and more preferably 1 to 2 times.

The ratio of the amount of ascorbic acid or a salt thereof added initially and the amount of ascorbic acid or a salt thereof added later when the reducing agent added later during the initial stage of polymerization and during the polymerization is ascorbic acid or a salt thereof is not particularly limited, but is referred to as "initial addition". The weight ratio of "ascorbic acid or a salt thereof"/"ascorbic acid or a salt thereof added batchwise" is usually 1/9 to 8/2, preferably 2/8 to 6/4, more preferably 3/7 In the range of ~ 5/5, the productivity of acrylic rubber production is excellent and it is suitable because it can highly balance the strength characteristics and injection moldability of the acrylic rubber veil produced.

The timing of the post-addition of the reducing agent is not particularly limited and is appropriately selected depending on the purpose of use, but is usually within the range of 1 hour after the start of polymerization, preferably 1 to 3 hours, more preferably 1.5 to 2.5 hours after the start of polymerization. At the same time, the productivity of acrylic rubber production is excellent and it is suitable because it can highly balance the strength characteristics and injection moldability of the acrylic rubber veil produced.

The addition amount per batch in the batchwise post-addition of the reducing agent is not particularly limited and is appropriately selected depending on the purpose of use, but is usually 0.00005 to 0.5 parts by weight, preferably 0.0001 to 0.1 parts by weight, based on 100 parts by weight of the monomer components. , more preferably 0.0005 to 0.05 parts by weight, particularly preferably 0.001 to 0.03 parts by weight, it is suitable because it can highly balance the strength characteristics and injection moldability of the acrylic rubber veil produced.

The operation after addition of the reducing agent is not particularly limited, but the polymerization reaction can be terminated after continuing the polymerization reaction for usually 30 minutes or longer, preferably 45 minutes or longer, more preferably 1 hour or longer.

The polymerization conversion ratio of the emulsion polymerization reaction is 90% by weight or more, preferably 95% by weight or more, and the acrylic rubber veil produced at this time has excellent strength characteristics and is suitable because it has no monomer odor. In terminating polymerization, you may use a polymerization terminator.

(solidification process)

The coagulation step in the production method of the acrylic rubber veil of the present invention is a step of contacting the obtained emulsion polymerization liquid with a coagulant to produce a hydrous crumb.

The solid concentration of the emulsion polymerization liquid used in this coagulation reaction is not particularly limited, but is usually adjusted to 5 to 50% by weight, preferably 10 to 45% by weight, and more preferably 20 to 40% by weight.

The coagulant used is not particularly limited, but metal salts are usually used. Examples of the metal salt include alkali metal salts, periodic table Group 2 metal salts, and other metal salts, preferably alkali metal salts and periodic table Group 2 metal salts, more preferably periodic table Group 2 metal salts. , Particularly preferably, magnesium salt is suitable because it can highly balance the water resistance, strength characteristics, fusibility and releasability of injection molding and processability of the obtained acrylic rubber veil.

Examples of alkali metal salts include sodium salts such as sodium chloride, sodium nitrate and sodium sulfate; potassium salts such as potassium chloride, potassium nitrate and potassium sulfate; Lithium salts, such as lithium chloride, lithium nitrate, and lithium sulfate, etc. are mentioned, Among these, sodium salt is preferable, and sodium chloride and sodium sulfate are especially preferable.

Examples of the Group 2 metal salt of the periodic table include magnesium chloride, calcium chloride, magnesium nitrate, calcium nitrate, magnesium sulfate, and calcium sulfate, and calcium chloride and magnesium sulfate are preferable.

Other metal salts include, for example, zinc chloride, titanium chloride, manganese chloride, iron chloride, cobalt chloride, nickel chloride, aluminum chloride, tin chloride, zinc nitrate, titanium nitrate, manganese nitrate, iron nitrate, cobalt nitrate, nitric acid Nickel, aluminum nitrate, tin nitrate, zinc sulfate, titanium sulfate, manganese sulfate, iron sulfate, cobalt sulfate, nickel sulfate, aluminum sulfate, tin sulfate and the like.

These coagulants can be used individually or in combination of two or more, and the amount used is usually 0.01 to 100 parts by weight, preferably 0.1 to 50 parts by weight, more preferably 0.1 to 50 parts by weight, based on 100 parts by weight of the monomer components. is in the range of 1 to 30 parts by weight. When the coagulant is within this range, it is suitable because the compression set resistance and water resistance can be highly improved when the acrylic rubber is crosslinked while ensuring sufficient coagulation of the acrylic rubber veil.

The contact between the emulsion polymerization liquid and the coagulant is not particularly limited and may be carried out according to a conventional method. By adding the emulsion polymerization liquid to the stirring coagulant liquid (coagulant solution), the resulting acrylic rubber hydrous crumb is 710 μm to 6.7 μm. It is suitable because it can remarkably improve the ash removal rate in washing and dewatering and the water resistance of the obtained acrylic rubber veil by concentrating to a particle diameter of mm.

The ratio of the resulting hydrous crumbs in the range of 710 μm to 6.7 mm (passing through 6.7 mm without passing through 710 μm) is not particularly limited, but is usually 30% by weight or more, preferably 50% by weight, based on the total amount of hydrous crumbs generated. When it is above, more preferably 60% by weight or more, particularly preferably 70% by weight or more, and most preferably 80% by weight or more, it is suitable because the water resistance of the acrylic rubber veil can be remarkably improved. In addition, the ratio of the resulting hydrous crumbs in the range of 710 μm to 4.75 mm (passing through 4.75 mm without passing through 710 μm) is not particularly limited, but is usually 30% by weight or more, preferably 50 When the amount is more than 60% by weight, more preferably more than 60% by weight, particularly preferably more than 70% by weight, and most preferably more than 80% by weight, it is suitable because the water resistance of the acrylic rubber veil can be remarkably improved. In addition, the ratio of the resulting hydrous crumbs in the range of 710 μm to 3.35 mm (passing through 3.35 mm without passing through 710 μm) is not particularly limited, but is usually 20% by weight or more, preferably 30 When the amount is more than 40% by weight, more preferably 40% by weight or more, particularly preferably 50% by weight or more, and most preferably 60% by weight or more, it is suitable because the water resistance of the acrylic rubber veil can be remarkably improved.

The means for generating the particle size of the hydrous crumb within the above range is not particularly limited, but, for example, adding a contact method between the emulsion polymerization liquid and the coagulant to the coagulant liquid (aqueous coagulant solution) in which the emulsion polymerization liquid is stirred. Alternatively, the concentration of the coagulant in the coagulating liquid, the number of agitation and the circumferential speed of the coagulating liquid being stirred can be carried out within a specific range.

The coagulant liquid used is usually used as an aqueous solution, but the concentration of the coagulant in the aqueous solution is usually 0.1 to 20% by weight, preferably 0.5 to 15% by weight, more preferably 1 to 10% by weight, particularly preferably is suitable because it can uniformly focus the particle size of the hydrous crumb produced when it is in the range of 1.5 to 5% by weight in a specific area.

The temperature of the coagulating solution is not particularly limited, but is suitable because uniform moistened crumbs are formed when it is usually in the range of 40 ° C. or higher, preferably 40 to 90 ° C., more preferably 50 to 80 ° C.

As a method of contacting the emulsion polymerization liquid and the coagulation liquid, a method of adding the emulsion polymerization liquid to the stirred coagulation liquid is selected, and the acrylic rubber veil obtained by remarkably excellent cleaning efficiency and dehydration efficiency of the resulting hydrous crumb It is suitable because it can highly improve the water resistance and storage stability of

The number of stirring (number of rotations) of the coagulating liquid being stirred is, that is, the number of rotations of the stirring blades of the stirring device, and is not particularly limited, but is usually 100 rpm or more, preferably 200 rpm or more, more preferably 200 to 1000 rpm, particularly preferably 300 to 900 rpm, most preferably 400 to 800 rpm.

As for the number of rotations, a rotation number that is vigorously stirred to a certain extent is more suitable because the grain size of the resulting hydrous crumbs can be made small and uniform, and by setting it to be more than the above lower limit, the formation of excessively large and small crumb grains is suppressed. Control of the coagulation reaction can be made easier by being able to do it, and setting it as below the said upper limit.

The circumferential speed of the coagulating solution being stirred, that is, the speed of the outer circumference of the stirring blades of the stirring device, is not particularly limited. Suitable, usually 0.5 m/s or more, preferably 1 m/s or more, more preferably 1.5 m/s or more, particularly preferably 2 m/s or more, and most preferably 2.5 m/s or more. On the other hand, the upper limit of the circumferential speed is not particularly limited, but usually solidifies when it is 50 m/s or less, preferably 30 m/s or less, more preferably 25 m/s or less, and most preferably 20 m/s or less. It is suitable because the control of the reaction becomes easy.

The shape and crumbs of the hydrous crumbs produced by setting the above conditions of the coagulation reaction (contact method, solid content concentration of the emulsion polymerization solution, concentration and temperature of the coagulation solution, rotation speed and circumferential speed during stirring of the coagulation solution, etc.) within a specific range It is suitable because the diameter is uniform and concentrated, the removal of the emulsifier and coagulant during washing and dehydration is remarkably improved, and the water resistance and storage stability of the resulting acrylic rubber veil can be highly improved.

(cleaning process)

The cleaning step in the production method of the acrylic rubber veil of the present invention is a step of washing the resulting hydrous crumb.

The cleaning method is not particularly limited, and can be performed by mixing the resulting hydrous crumb with a large amount of water, for example.

The amount of water added for washing is not particularly limited, but is usually 50 parts by weight or more, preferably 50 to 15,000 parts by weight, and more preferably 100 to 10,000 When it is in the range of parts by weight, more preferably 500 to 5,000 parts by weight, it is suitable because the amount of ash in the acrylic rubber veil can be effectively reduced.

The temperature of the water to be used is not particularly limited, but it is preferable to use warm water, and it is usually 40 ° C. or higher, preferably 40 to 100 ° C., more preferably 50 to 90 ° C., particularly 60 to 80 ° C. It is optimal because it can significantly increase efficiency. By setting the temperature of the water to be used equal to or higher than the above lower limit, the emulsifier and the coagulant are released from the hydrous crumb, and the cleaning efficiency is further improved.

The washing time is not particularly limited, but is usually in the range of 1 to 120 minutes, preferably 2 to 60 minutes, and more preferably 3 to 30 minutes.

The number of times of washing (water washing) is not particularly limited, and is usually 1 to 10 times, preferably 1 to 5 times, and more preferably 2 to 3 times. On the other hand, from the viewpoint of reducing the residual amount of the coagulant in the finally obtained acrylic rubber veil, it is preferable to increase the number of times of washing with water. By setting it as the said range, the number of times of washing with water can be reduced remarkably.

(moisture removal process)

In the present invention, it is preferable that the water-containing crumb supplied to the screw-type twin-screw extrusion dryer is one in which free water is removed (moisture removal) after washing.

As the moisture eliminator, known ones can be used without particular limitation, and examples thereof include wire meshes, screens, rolling elements, and the like, and preferably wire meshes and screens.

The size of the eyes of the water remover is not particularly limited, but is usually in the range of 0.01 to 5 mm, preferably 0.1 to 1 mm, and more preferably 0.2 to 0.6 mm, the loss of the water-containing crumb is small and the water removal can be efficiently performed. It's good.

The water content of the water-containing crumb after water removal, that is, the water content of the water-containing crumb introduced into the dewatering/drying process is not particularly limited, but is usually 50 to 80% by weight, preferably 50 to 70% by weight, more preferably 50 to 80% by weight. It is in the range of 60% by weight.

The temperature of the water-containing crumb after water removal, that is, the temperature of the water-containing crumb introduced into the dehydration/drying step, is not particularly limited, but is usually 40 ° C. or higher, preferably 40 to 100 ° C., more preferably 50 to 90 ° C. Especially preferably in the range of 55 to 85 ° C, most preferably 60 to 80 ° C, the specific heat is 1.5 to 2.5 KJ / kg K, like the acrylic rubber of the present invention, so that it is difficult to increase the temperature. It is suitable because it can dehydrate and dry efficiently using a twin-screw extrusion dryer.

(Dehydration/drying/forming process)

In the dewatering/drying/molding step in the method for producing an acrylic rubber veil of the present invention, the water-containing crumbs, which have been washed and, if necessary, removed water, are subjected to a dewatering barrel having a dewatering slit, a drying barrel under reduced pressure, and a die at the tip. It is a step of extruding sheet-like dry rubber from a die by dehydrating the water content to 1 to 40% by weight with a dehydration barrel and then drying to less than 1% by weight with a drying barrel using a screw-type twin screw extrusion dryer having a screw type.

(Dehydration of hydrous crumb in dehydration barrel part)

Dehydration of the water-containing crumb is performed in a dewatering barrel in a screw-type twin-screw extrusion dryer having a dehydration slit. The size of the opening of the dewatering slit may be appropriately selected depending on the conditions of use, but when it is in the range of usually 0.01 to 5 mm, preferably 0.1 to 1 mm, and more preferably 0.2 to 0.6 mm, the loss of the water-containing crumb is small and the water-containing crumb Suitable for efficient dehydration.

The number of dewatering barrels in the screw-type twin-screw extrusion dryer is not particularly limited, but is usually plural, preferably 2 to 10, more preferably 3 to 6, so that the adhesive acrylic rubber can be dewatered efficiently. good in doing

There are two types of removal of water from the brine crumb in the dewatering barrel: removal in liquid phase from the dewatering slit (drainage) and removal in vapor phase (double steam). In the present invention, drainage is dehydration, Double steam is distinguished by defining it as pre-drying.

Water discharged from the dewatering slit in the dewatering of the hydrous crumb may be in either liquid phase (drainage) or vapor phase (exhaust steam). Combining drainage and steam drainage makes it possible to efficiently dehydrate the adhesive acrylic rubber and is suitable. The selection of a drain type dewatering barrel or a double steam type dehydration barrel of a screw type twin screw extrusion dryer having three or more dehydration barrels may be appropriately performed depending on the purpose of use. The number of drain type barrels is increased, and when the water content is reduced, the number of double steam type barrels is increased.

The set temperature of the dehydration barrel is appropriately selected depending on the monomer composition of the acrylic rubber, ash content, water content, operating conditions, etc., but is usually 60 to 150 ° C, preferably 70 to 140 ° C, more preferably 80 to 130 ° C. is the range The set temperature of the dewatering barrel for dehydration in the drained state is usually 60°C to 120°C, preferably 70 to 110°C, and more preferably 80 to 100°C. The set temperature of the dewatering barrel for dehydration in the double steam state is usually in the range of 100 to 150°C, preferably 105 to 140°C, and more preferably 110 to 130°C.

The water content after dewatering in drainage type dewatering, in which water is squeezed out of the water-containing crumb, is not particularly limited, but is usually 1 to 40% by weight, preferably 5 to 35% by weight, more preferably 10 to 35% by weight. Productivity and ash removal efficiency are highly balanced and suitable.

When dehydration of adhesive acrylic rubber having reactive groups is carried out using a centrifugal separator or the like, the acrylic rubber adheres to the dehydration slit and dehydration is hardly possible (moisture content is up to about 45 to 55% by weight), but in the present invention , By using a screw-type twin-screw extrusion dryer that has a dewatering slit and is forcibly squeezed with a screw, the water content can be reduced to this point.

For dewatering of the water-containing crumb in the case of providing a drain type dewatering barrel and a double steam type dewatering barrel, the water content after draining in the drain type dewatering barrel part is usually 5 to 40% by weight, preferably 10 to 40% by weight, more preferably It is preferably 15 to 35% by weight, and the water content after pre-drying in the double steam type dehydration barrel is usually 1 to 30% by weight, preferably 3 to 20% by weight, and more preferably 5 to 15% by weight.

By setting the water content after dehydration to the above lower limit or more, the dehydration time can be shortened and deterioration of the acrylic rubber can be suppressed, and by setting it to the above upper limit or less, the amount of ash can be sufficiently reduced.

(Drying of water-containing crumbs in the drying barrel part)

It is characterized in that the drying of the hydrous crumb after dehydration is performed in a drying barrel under reduced pressure by a screw-type twin-screw extrusion dryer having a drying barrel. By drying the acrylic rubber under reduced pressure, the production efficiency of drying is increased, and air inherent in the acrylic rubber is removed, and an acrylic rubber veil with high specific gravity and excellent storage stability can be manufactured, which is suitable. In the present invention, the storage stability of the acrylic rubber veil can be further improved by melting the acrylic rubber under reduced pressure and extruding and drying it. The storage stability of the acrylic rubber veil can be controlled largely in correlation with the specific gravity of the acrylic rubber veil, but when the specific gravity is large and high storage stability is controlled, it can be controlled by the degree of reduced pressure of extrusion drying.

The depressurization degree of the drying barrel may be appropriately selected, but when it is usually 1 to 50 kPa, preferably 2 to 30 kPa, and more preferably 3 to 20 kPa, the hydrous crumb can be efficiently dried, and the acrylic rubber bale It is suitable because it can remarkably improve the storage stability of acrylic rubber by removing air.

The set temperature of the drying barrel may be appropriately selected, but it is usually in the range of 100 to 250°C, preferably 110 to 200°C, and more preferably 120 to 180°C, efficiently without thermal deterioration or deterioration of acrylic rubber. It is suitable because it can dry and can reduce the gel amount of the methyl ethyl ketone insoluble part in an acrylic rubber veil.

The number of drying barrels in the screw-type twin-screw extrusion dryer is not particularly limited, but is usually plural, preferably 2 to 10, and more preferably 3 to 8. The decompression degree in the case of having a plurality of drying barrels may be an approximate decompression degree in all the drying barrels, or may be changed. In the case of having a plurality of drying barrels, the set temperature may be approximated or changed in all drying barrels. It is suitable because it can increase efficiency.

The water content of the dried rubber after drying is usually less than 1% by weight, preferably 0.8% by weight or less, and more preferably 0.6% by weight or less. In the present invention, especially in the screw-type twin-screw extrusion dryer, the water content of dry rubber is set to this value (a state in which water is almost removed) and melt-extruded is the methyl ethyl ketone insoluble content of sheet-like or veil-like acrylic rubber. It is suitable because the amount of gel can be reduced. In the present invention, an acrylic rubber bale melt-kneaded or melt-kneaded and dried with a screw-type twin-screw extrusion dryer is suitable because both characteristics of strength characteristics and Banbury workability are highly balanced. On the other hand, "melt kneading" or "melt kneading and drying" as used in the present invention means that acrylic rubber is kneaded (mixed) in a molten state or extruded in a molten state in a screw-type twin screw extrusion dryer, and then dried at that stage. Or, it means that acrylic rubber is kneaded in a molten (plasticized) state by a screw-type twin-screw extrusion dryer, extruded, and dried.

In the present invention, the shear rate applied in the drying barrel of the screw-type twin screw extrusion dryer in a state in which the acrylic rubber does not substantially contain water is not particularly limited, but is usually 5 [1 / s] or more , Preferably in the range of 10 to 400 [1 / s], more preferably in the range of 20 to 250 [1 / s] Storage stability, injection moldability, Banbury processability, strength characteristics, and compression resistance of the obtained acrylic rubber veil The permanent deformation characteristics are highly balanced and suitable.

The shear viscosity of the acrylic rubber in the screw-type twin-screw extrusion dryer used in the present invention, particularly in the drying barrel, is not particularly limited, but is usually 12000 [Pa s] or less, preferably 1000 to 12000 [Pa s]. ], more preferably 2000 to 10000 [Pa s], particularly preferably 3000 to 7000 [Pa s], most preferably 4000 to 6000 [Pa s], preservation of the obtained acrylic rubber veil Stability, injection moldability, Banbury processability, and strength characteristics are highly balanced and suitable.

(Extrusion of dry rubber from die part)

The dry rubber dehydrated and dried in the screw portion of the dewatering barrel and the drying barrel is sent to the screwless straightening die portion, and extruded from the die portion into a desired shape. Between the screw portion and the die portion, a breaker plate or wire mesh may or may not be provided.

The extruded dry rubber is suitable because, by making the die shape substantially rectangular and feeding it out in a sheet form, a dry rubber excellent in storage stability with little mixing of air and high specific gravity is obtained.

The resin pressure in the die portion is not particularly limited, but is usually in the range of 0.1 to 10 MPa, preferably 0.5 to 5 MPa, and more preferably 1 to 3 MPa. It is suitable because it is small (specific gravity is high) and productivity is excellent.

(Screw type twin screw extrusion dryer and operating conditions)

The screw length (L) of the screw-type twin-screw extrusion dryer used may be appropriately selected depending on the purpose of use, but is usually in the range of 3000 to 15000 mm, preferably 4000 to 10000 mm, and more preferably 4500 to 8000 mm.

The screw diameter (D) of the screw type twin screw extrusion dryer used may be appropriately selected depending on the purpose of use, but is usually in the range of 50 to 250 mm, preferably 100 to 200 mm, and more preferably 120 to 160 mm.

The ratio (L/D) of the screw length (L) to the screw diameter (D) of the screw type twin screw extrusion dryer used is not particularly limited, but is usually 10 to 100, preferably 20 to 80, more preferably When is in the range of 30 to 60, it is suitable because the water content can be reduced to less than 1% by weight without causing molecular weight reduction or thermal deterioration of dry rubber.

The number of revolutions (N) of the screw-type twin-screw extrusion dryer used may be appropriately selected depending on various conditions, but is usually 10 to 1000 rpm, preferably 50 to 750 rpm, more preferably 100 to 500 rpm, and most preferably Preferably, at 120 to 300 rpm, the water content of the acrylic rubber veil and the gel amount of the methyl ethyl ketone insoluble content can be efficiently reduced, so it is suitable.

The extrusion amount (Q) of the screw type twin screw extrusion dryer used is not particularly limited, but is usually 100 to 1500 kg/hr, preferably 300 to 1200 kg/hr, more preferably 400 to 1000 kg/hr, Most preferably, it is in the range of 500 to 800 kg/hr.

The ratio (Q/N) of the amount of extrusion (Q) and the number of rotations (N) of the screw-type twin-screw extrusion dryer used is not particularly limited, but is usually 2 to 10, preferably 3 to 8, more preferably is in the range of 4 to 6.

The maximum torque of the screw type twin screw extrusion dryer used is not particularly limited, but is usually 5 to 125 N m, preferably 10 to 100 N m, more preferably 10 to 50 N m, particularly preferably When it is in the range of 15 to 45 N m, it is suitable because it can highly balance the injection moldability, Banbury processability, and strength characteristics of the acrylic rubber veil to be produced.

The specific power of the screw-type twin-screw extrusion dryer used is not particularly limited, but is usually 0.01 to 0.3 [kw h/kg] or more, preferably 0.05 to 0.2 [kw h/kg], more preferably 0.1 In the range of ~ 0.2 [kw h / kg], the injection moldability, Banbury processability, and strength characteristics of the acrylic rubber veil obtained are highly balanced and suitable.

The specific power of the screw-type twin-screw extrusion dryer used is not particularly limited, but is usually 0.1 to 0.6 [A h/kg] or more, preferably 0.15 to 0.55 [A h/kg], more preferably 0.2 In the range of ~ 0.5 [A h / kg], the injection moldability, Banbury processability, and strength characteristics of the acrylic rubber veil obtained are highly balanced and suitable.

The shear rate of the screw-type twin screw extrusion dryer used is not particularly limited, but is usually 5 to 150 [1/s] or more, preferably 10 to 100 [1/s], more preferably 25 to 75 [1/s]. /s], the storage stability, injection moldability, Banbury processability, and strength characteristics of the obtained acrylic rubber veil are highly balanced and suitable.

The shear viscosity of the acrylic rubber in the screw-type twin-screw extrusion dryer used is not particularly limited, but is usually 4000 to 8000 [Pa s] or less, preferably 4500 to 7500 [Pa s], more preferably 5000 to 8000 [Pa s]. In the range of 7000 [Pa s], the storage stability, injection moldability, Banbury processability, and strength characteristics of the obtained acrylic rubber veil are highly balanced and suitable.

Thus, in this invention, dehydration, drying, and shaping|molding on high shear conditions become possible by using the extrusion dryer which has a 2-screw screw, and it is suitable.

(sheet-shaped dry rubber)

The shape of the dry rubber extruded from the screw-type twin-screw extrusion dryer is sheet-like, and at this time, the specific gravity can be increased without entraining air, and the storage stability is highly improved, which is suitable. Sheet-like dry rubber extruded from the screw-type twin-screw extrusion dryer is usually cooled and cut to be used as sheet-like acrylic rubber.

The thickness of the sheet-like dry rubber extruded from the screw-type twin-screw extrusion dryer is not particularly limited, but is usually 1 to 40 mm, preferably 2 to 35 mm, more preferably 3 to 30 mm, and most preferably 5 to 25 mm. When within the range, workability and productivity are excellent and suitable. In particular, since the thermal conductivity of the sheet-like dry rubber is as low as 0.15 to 0.35 W/mK, the thickness of the sheet-like dry rubber in the case of significantly improving productivity by increasing the cooling efficiency is usually 1 to 30 mm, preferably 2 to 25 mm, It is more preferably in the range of 3 to 15 mm, particularly preferably in the range of 4 to 12 mm.

The width of the sheet-shaped dry rubber extruded from the screw-type twin-screw extrusion dryer is appropriately selected depending on the purpose of use, but is usually in the range of 300 to 1200 mm, preferably 400 to 1000 mm, and more preferably 500 to 800 mm.

The temperature of the dried rubber extruded from the screw-type twin-screw extrusion dryer is not particularly limited, but is usually in the range of 100 to 200°C, preferably 110 to 180°C, and more preferably 120 to 160°C.

The water content of the dry rubber extruded from the screw-type twin-screw extrusion dryer is not particularly limited, but is usually less than 1% by weight, preferably 0.8% by weight or less, and more preferably 0.6% by weight or less.

The complex viscosity at 100 ° C. ([η] 100 ° C.) of the sheet-like dry rubber extruded from the screw-type twin-screw extrusion dryer is not particularly limited, but is usually 1500 to 6000 [Pa s], preferably 2000 In the range of to 5000 [Pa s], more preferably 2500 to 4500 [Pa s], and most preferably 3000 to 4000 [Pa s], the extrudability and shape retention properties as a sheet are highly balanced and suitable. . That is, by setting it to the lower limit or more, extrudability can be made more excellent, and by setting it to the upper limit or less, the shape collapse and breakage of the sheet-shaped dry rubber can be suppressed.

(cooling process ~ cutting process)

The sheet-like dry rubber extruded from the screw-type twin-screw extrusion dryer may be folded as it is and used, but usually it can be cut and used.

The cutting of the sheet-like dry rubber is not particularly limited, but since the acrylic rubber of the present invention has strong adhesiveness, it is preferable to cool the sheet-like dry rubber in order to continuously cut it without entraining air.

The cutting temperature of the sheet-like dry rubber is not particularly limited, but is usually 60°C or lower, preferably 55°C or lower, and more preferably 50°C or lower, as cutting properties and productivity are highly balanced and suitable.

The complex viscosity ([η] 60°C) of the sheet-like dry rubber at 60°C is not particularly limited, but is usually 15,000 [Pa s] or less, preferably 2000 to 10,000 [Pa s], more preferably Preferably in the range of 2,500 to 7,000 [Pa s], most preferably 2,700 to 5,500 [Pa s], it is suitable because it can be cut continuously without entraining air.

The ratio of the complex viscosity at 100°C ([η]100°C) to the complex viscosity at 60°C ([η]60°C) of the sheet-like dry rubber ([η]100°C/[η]60°C) is , is not particularly limited, and may be appropriately selected according to the purpose of use, but is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more, complex viscosity at 100 ° C. of sheet-like dry rubber ([η] 100 ° C.) The ratio ([η]100°C/[η]60°C) of the complex viscosity at 60°C ([η]60°C) is usually 0.5 to 0.99, preferably 0.55 to 0.95, more preferably When the range is 0.6 to 0.9, particularly preferably 0.65 to 0.85, and most preferably 0.7 to 0.8, the air entrainment is low, and cutting and productivity are highly balanced and are suitable.

The cooling method of the sheet-like dry rubber is not particularly limited and may be left at room temperature. However, since the thermal conductivity of the sheet-like dry rubber is very small at 0.15 to 0.35 W/mK, air cooling under blowing or air conditioning, or spraying water Forced cooling such as a splashing method or an immersion method in which water is immersed in water is preferable because it increases productivity, and an air cooling method under blowing or cooling is particularly suitable.

In the air-cooling method of sheet-like dry rubber, for example, sheet-like dry rubber can be extruded from a screw extruder onto a conveying machine such as a belt conveyor, conveyed and cooled while blowing cold air. The temperature of the cooling air is not particularly limited, but is usually in the range of 0 to 25°C, preferably 5 to 25°C, and more preferably 10 to 20°C. The cooling rate is not particularly limited, but cutting becomes easy when it is usually 40°C/hr or more, preferably 50°C/hr or more, more preferably 100°C/hr or more, and particularly preferably 150°C/hr or more. suitable In the present invention, the cooling rate of the sheet-shaped dry rubber is usually 40°C/hr or more, preferably 50°C/hr or more, more preferably 100°C/hr or more, and particularly preferably 150°C/hr or more. In the case of the above, scorch stability when an acrylic rubber veil is used as a rubber composition is excellent and suitable.

The cut length of the sheet-like dry rubber is not particularly limited and is appropriately selected depending on the purpose of use, but is usually in the range of 100 to 800 mm, preferably 200 to 500 mm, and more preferably 250 to 450 mm.

(lamination process)

The lamination step in the production method of the acrylic rubber veil of the present invention is a step of obtaining an acrylic rubber veil with less entrainment of air and excellent storage stability by laminating the sheet-shaped dry rubber.

The lamination temperature of the sheet-like dry rubber is not particularly limited, but is usually 30°C or higher, preferably 35°C or higher, and more preferably 40°C or higher, since air entrained during lamination can be released, and is suitable. The number of laminated sheets may be appropriately selected according to the size or weight of the acrylic rubber veil. The acrylic rubber veil of the present invention is integrated by the weight of the laminated sheet-like dry rubber.

The acrylic rubber veil of the present invention obtained in this way is superior in operability compared to crumb-like acrylic rubber, and is also excellent in Banbury processability, crosslinkability, strength characteristics, compression set resistance, and water resistance, as well as storage stability and injection molding properties. It has excellent properties, and it can be used as it is or by cutting the required amount and putting it into a mixer such as Banbury or Roll.

<Rubber composition>

The rubber composition of the present invention is characterized by comprising a rubber component including the acrylic rubber veil, a filler, and a crosslinking agent.

As the rubber component serving as the main component of the rubber composition of the present invention, the acrylic rubber veil of the present invention may be used alone or, if necessary, may be used in combination with the acrylic rubber veil of the present invention and other rubber components. The content of the acrylic rubber veil of the present invention in the rubber component may be selected according to the purpose of use, and is, for example, usually 30% by weight or more, preferably 50% by weight or more, and more preferably 70% by weight or more. .

Other rubber components to be combined with the acrylic rubber veil of the present invention are not particularly limited, and examples thereof include natural rubber, polybutadiene rubber, polyisoprene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and silicone rubber. , fluororubber, olefin-based elastomer, styrene-based elastomer, vinyl chloride-based elastomer, polyester-based elastomer, polyamide-based elastomer, polyurethane-based elastomer, polysiloxane-based elastomer, and the like.

These other rubber components can be used alone or in combination of two or more. The shape of these other rubber components may be crumb, strand, veil, sheet, or powder. The content of the other rubber components in the entire rubber component is appropriately selected within a range that does not impair the effects of the present invention, and is, for example, usually 70% by weight or less, preferably 50% by weight or less, more preferably 30% by weight or less.

The filler included in the rubber composition is not particularly limited, but examples thereof include reinforcing fillers and non-reinforcing fillers. Preferably, when a reinforcing filler is used, the Banbury processability of the rubber composition, injection moldability, and It is suitable because it has excellent crosslinkability in a short time and highly excellent water resistance, strength characteristics, and compression set resistance of the crosslinked product.

Examples of reinforcing fillers include carbon blacks such as furnace black, acetylene black, thermal black, channel black, and graphite; silicas such as wet silica, dry silica, and colloidal silica; etc. can be mentioned. Examples of non-reinforcing fillers include quartz powder, diatomaceous earth, zinc oxide, basic magnesium carbonate, activated calcium carbonate, magnesium silicate, aluminum silicate, titanium dioxide, talc, aluminum sulfate, calcium sulfate, and barium sulfate.

These fillers can be used individually or in combination of two or more, and the blending amount thereof is appropriately selected within a range that does not impair the effect of the present invention, and is usually 1 to 200 parts by weight based on 100 parts by weight of the rubber component. part, preferably 10 to 150 parts by weight, more preferably 20 to 100 parts by weight.

The crosslinking agent used in the rubber composition is not particularly limited, and conventionally known crosslinking agents are selected depending on the purpose of use, and examples thereof include inorganic crosslinking agents such as sulfur compounds and organic crosslinking agents, preferably organic crosslinking agents. . The crosslinking agent may be any of a polyvalent compound or a monovalent compound, but a polyvalent compound having two or more reactive groups is preferable. As the crosslinking agent, any of an ion crosslinkable compound or a radical crosslinkable compound may be used, but an ion crosslinkable compound is preferred.

The organic crosslinking agent is not particularly limited, but an ionic crosslinkable organic compound is preferred, and a polyvalent ion organic compound is particularly preferred. When the crosslinking agent is a polyvalent ion organic compound (polyvalent ion crosslinkable compound), the rubber composition has excellent Banbury processability, injection moldability, and short-time crosslinking properties, and the crosslinked product has excellent water resistance, strength characteristics, and compression set resistance. It is particularly suitable because it is highly excellent. The "ion" of the ion crosslinkable or polyvalent ion is not particularly limited as long as it is an ion reactive ion, for example, an ion reactive group of the ion reactive group-containing monomer of the above acrylic rubber, but preferably amine ion-crosslinkable organic compounds having ion-reactive groups such as groups, epoxy groups, carboxyl groups, and thiol groups.

Specific examples of the polyvalent ion organic compound include polyvalent amine compounds, polyvalent epoxy compounds, polyvalent carboxylic acid compounds, and polyvalent thiol compounds, preferably polyvalent amine compounds and polyvalent thiol compounds, more preferably polyvalent amines. it is a compound

Examples of the polyhydric amine compound include aliphatic polyhydric amine compounds such as hexamethylenediamine, hexamethylenediamine carbamate, and N,N'-dicinnamylidene-1,6-hexanediamine; 4,4'-methylenedianiline, p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-(m -Phenylenediisopropylidene)dianiline, 4,4'-(p-phenylenediisopropylidene)dianiline, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 4,4 Aromatic polyvalent compounds such as '-diaminobenzanilide, 4,4'-bis(4-aminophenoxy)biphenyl, m-xylylenediamine, p-xylylenediamine, and 1,3,5-benzenetriamine amine compounds; etc. can be mentioned. Among these, hexamethylenediamine carbamate, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, etc. are preferable. As a polyhydric amine compound, these carbonate salts can also be used conveniently. These polyhydric amine compounds are particularly suitably used in combination with a carboxyl group-containing acrylic rubber veil or an epoxy group-containing acrylic rubber veil.

As the polyvalent thiol compound, a triazine thiol compound is preferably used, for example, 6-trimercapto-s-triazine, 2-anilino-4,6-dithiol-s-triazine, 1 -Dibutylamino-3,5-dimercaptotriazine, 2-dibutylamino-4,6-dithiol-s-triazine, 1-phenylamino-3,5-dimercaptotriazine, 2,4,6-trimercapto-1,3,5-triazine, 1-hexylamino-3,5-dimercaptotriazine, etc. are mentioned. These triazinethiol compounds are particularly suitably used in combination with a chlorine atom-containing acrylic rubber veil.

Examples of other polyvalent organic compounds include polyvalent carboxylic acid compounds such as tetradecanedioic acid, and dithiocarbamic acid metal salts such as zinc dimethyldithiocarbamate. These other polyvalent organic compounds are particularly suitably used in combination with an epoxy group-containing acrylic rubber veil.

These crosslinking agents can be used individually or in combination of two or more, and the compounding amount is usually 0.001 to 20 parts by weight, preferably 0.1 to 10 parts by weight, more preferably 0.1 to 100 parts by weight of the rubber component. ~ 5 parts by weight. By making the compounding quantity of a crosslinking agent into this range, it is suitable because it can make it excellent in mechanical strength as a rubber crosslinked material, making rubber elasticity sufficient.

In the rubber composition of the present invention, an anti-aging agent may be incorporated as needed. The type of anti-aging agent is not particularly limited, and examples thereof include 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butylphenol, butylhydroxyanisole, and 2,6-di-t-butyl-4-methylphenol. -Di-t-butyl-α-dimethylamino-p-cresol, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, styrenated phenol, 2,2' -Methylene-bis(6-α-methyl-benzyl-p-cresol), 4,4'-methylenebis(2,6-di-t-butylphenol), 2,2'-methylene-bis(4-methyl -6-t-butylphenol), 2,4-bis[(octylthio)methyl]-6-methylphenol, 2,2'-thiobis-(4-methyl-6-t-butylphenol), 4, 4'-thiobis-(6-t-butyl-o-cresol), 2,6-di-t-butyl-4-(4,6-bis(octylthio)-1,3,5-triazine- other phenolic antioxidants such as 2-ylamino)phenol; phosphite ester anti-aging agents such as tris (nonylphenyl) phosphite, diphenyl isodecyl phosphite, and tetraphenyldipropylene glycol diphosphite; sulfur ester-based anti-aging agents such as dilauryl thiodipropionate; Phenyl-α-naphthylamine, phenyl-β-naphthylamine, p-(p-toluenesulfonylamide)-diphenylamine, 4,4′-(α,α-dimethylbenzyl)diphenylamine, N, amine anti-aging agents such as N-diphenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, and butyraldehyde-aniline condensates; imidazole-based anti-aging agents such as 2-mercaptobenzimidazole; quinoline anti-aging agents such as 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline; hydroquinone-based anti-aging agents such as 2,5-di-(t-amyl)hydroquinone; etc. can be mentioned. Among these, an amine-type anti-aging agent is especially preferable.

These antioxidants can be used individually or in combination of two or more, and the compounding amount is 0.01 to 15 parts by weight, preferably 0.1 to 10 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the rubber component. It is in the range of 1 to 5 parts by weight.

The rubber composition of the present invention includes the rubber component including the acrylic rubber veil of the present invention, a filler, and a crosslinking agent as essential components and, if necessary, an anti-aging agent, and, if necessary, is commonly used in the art. Other additives such as crosslinking aids, crosslinking accelerators, crosslinking retardants, silane coupling agents, plasticizers, processing aids, lubricants, pigments, colorants, antistatic agents, foaming agents, and the like may be optionally incorporated. These other compounding agents can be used individually or in combination of two or more types, respectively, and the compounding amount is appropriately selected within a range not impairing the effect of the present invention.

As a method for producing the rubber composition of the present invention, a method of mixing a rubber component containing the acrylic rubber veil of the present invention, a filler, a crosslinking agent, and an anti-aging agent or other compounding agents that may be contained as necessary may be mentioned. , Any means used in the conventional rubber processing field, such as an open roll, a Banbury mixer, and various types of kneaders, can be used for mixing. The mixing order of each component may be carried out in the usual order in the field of rubber processing. For example, after sufficiently mixing components that are difficult to react or decompose by heat, a crosslinking agent that is a component that is easily reacted or decomposed by heat It is preferable to mix the etc. in a short time at a temperature at which no reaction or decomposition occurs.

<Crosslinked Rubber>

The crosslinked rubber product of the present invention is formed by crosslinking the above rubber composition.

The crosslinked rubber product of the present invention is formed by using the rubber composition of the present invention with a molding machine corresponding to a desired shape, such as an extruder, injection molding machine, compressor, or roll, and heating to perform a crosslinking reaction, It can be manufactured by fixing the shape as a rubber crosslinked product. In this case, crosslinking may be performed after molding in advance, or crosslinking may be performed simultaneously with molding. The molding temperature is usually 10 to 200°C, preferably 25 to 150°C. The crosslinking temperature is usually 100 to 250°C, preferably 130 to 220°C, more preferably 150 to 200°C, and the crosslinking time is usually 0.1 minute to 10 hours, preferably 1 minute to 5 hours. As the heating method, methods used for crosslinking rubber such as press heating, steam heating, oven heating, and hot air heating may be appropriately selected.

The cross-linked rubber of the present invention may be subjected to secondary cross-linking by further heating depending on the shape, size and the like of the cross-linked rubber. Secondary crosslinking varies depending on the heating method, crosslinking temperature, shape, etc., but is preferably carried out for 1 to 48 hours. What is necessary is just to select a heating method and a heating temperature suitably.

The crosslinked rubber of the present invention has excellent compression set resistance and water resistance while maintaining the basic properties of rubber such as tensile strength, elongation and hardness.

The rubber crosslinked product of the present invention takes advantage of the above characteristics and, for example, O-rings, packings, diaphragms, oil seals, shaft seals, bearing seals, mechanical seals, wellhead seals, seals for electrical and electronic equipment, air compression sealing materials such as seals for instruments; A rocker cover gasket attached to the connection between the cylinder block and the cylinder head, an oil pan gasket attached to the connection between the oil pan and the cylinder head or transmission case, and between a pair of housings that insert the unit cell having the positive electrode, the electrolyte plate, and the negative electrode. various gaskets such as gaskets for fuel cell separators and gaskets for top covers of hard disk drives; buffer material, anti-vibration material; wire covering materials; industrial belts; tubes and hoses; sheets; etc. are used suitably.

The crosslinked rubber product of the present invention is also an extrusion molded article and molded crosslinked product used for automobile applications, for example, fuel hoses, filler neck hoses, vent hoses, paper hoses, fuel tanks such as oil hoses, etc. It is suitably used for various hoses such as oil-based hoses, turbo air hoses, air-type hoses such as mission control hoses, radiator hoses, heater hoses, brake hoses, and air-conditioner hoses.

<Equipment configuration used for manufacturing acrylic rubber veil>

Next, the configuration of an apparatus used for manufacturing an acrylic rubber veil according to an embodiment of the present invention will be described. 1 is a diagram schematically showing an example of an acrylic rubber manufacturing system having a device configuration used for manufacturing an acrylic rubber veil according to an embodiment of the present invention. For example, the acrylic rubber production system 1 shown in FIG. 1 can be used for production of the acrylic rubber veil according to the present invention.

The acrylic rubber manufacturing system 1 shown in FIG. 1 is constituted by an emulsion polymerization reactor, a coagulation device 3, a washing device 4, a moisture remover 43, and a screw-type twin-screw extrusion dryer (not shown).

The emulsion polymerization reactor is configured to perform processing related to the emulsion polymerization step described above. Although not shown in FIG. 1, this emulsion polymerization reactor has, for example, a polymerization reactor, a temperature control unit for controlling the reaction temperature, a motor, and an agitator equipped with agitating blades. In the emulsion polymerization reactor, monomer components for forming acrylic rubber are mixed with water and an emulsifier, emulsified while appropriately stirred with a stirrer, and an emulsion polymerization reaction is initiated in the presence of a redox catalyst composed of an organic radical generator and a reducing agent, An emulsion polymerization solution may be obtained by post-adding a chain transfer agent batchwise during the polymerization. The emulsion polymerization reactor may be any of a batch type, semi-batch type and continuous type, and may be either a tank type reactor or a tubular type reactor.

The solidification device 3 shown in FIG. 1 is configured to perform processing related to the above-described solidification step. As schematically shown in FIG. 1 , the coagulation device 3 includes, for example, a stirring tank 30, a heating unit 31 for heating the inside of the stirring tank 30, and the temperature inside the stirring tank 30. It has a drive control unit (not shown) that controls the temperature controller (not shown), the stirring device 34 provided with the motor 32 and the stirring blades 33, and the number of revolutions and rotational speed of the stirring blades 33. In the coagulation device 3, the emulsion polymerization liquid obtained in the emulsion polymerization reactor is brought into contact with the coagulation liquid to solidify, whereby a water-containing crumb can be produced.

In the coagulation device 3, for example, a method of adding the emulsion polymerization solution to the stirring coagulation solution is employed for the contact between the emulsion polymerization solution and the coagulation solution. That is, a water-containing crumb is produced by filling the stirring tank 30 of the coagulation device 3 with a coagulating liquid, adding and bringing the emulsion polymerization liquid into contact with the coagulating liquid to solidify the emulsion polymerization liquid.

The heating unit 31 of the coagulation device 3 is configured to heat the coagulating liquid filled in the stirring vessel 30 . In addition, the temperature control unit of the coagulation device 3 is configured to control the temperature in the stirring vessel 30 by controlling the heating operation by the heating unit 31 while monitoring the temperature in the stirring vessel 30 measured with a thermometer. has been The temperature of the coagulating liquid in the stirring vessel 30 is controlled by the temperature controller to be in the range of usually 40°C or higher, preferably 40 to 90°C, and more preferably 50 to 80°C.

The stirring device 34 of the coagulation device 3 is configured to stir the coagulating liquid filled in the stirring tank 30 . Specifically, the stirring device 34 includes a motor 32 that generates rotational power, and a stirring blade 33 that extends in a vertical direction with respect to the rotating shaft of the motor 32 . The agitating blade 33 can cause the coagulating liquid to flow by rotating centering on the rotating shaft by the rotational power of the motor 32 within the coagulating liquid filled in the stirring tank 30 . The shape and size of the stirring blades 33, the number of installations, and the like are not particularly limited.

The driving control unit of the coagulation device 3 controls the rotation drive of the motor 32 of the stirring device 34 to set the number of rotations and the rotational speed of the stirring blades 33 of the stirring device 34 to predetermined values. Consists of. The stirring rate of the coagulating liquid is, for example, usually 100 rpm or more, preferably 200 to 1000 rpm, more preferably 300 to 900 rpm, particularly preferably 400 to 800 rpm, and stirred by the driving control unit. Rotation of the wing 33 is controlled. The circumferential velocity of the coagulating solution is usually 0.5 m/s or more, preferably 1 m/s or more, more preferably 1.5 m/s or more, particularly preferably 2 m/s or more, and most preferably 2.5 m/s or more. The rotation of the stirring blade 33 is controlled by the drive control unit so that it becomes s or more. In addition, the drive is such that the upper limit of the circumferential speed of the coagulating liquid is usually 50 m/s or less, preferably 30 m/s or less, more preferably 25 m/s or less, and most preferably 20 m/s or less. Rotation of the agitation blade 33 is controlled by the control unit.

The cleaning device 4 shown in FIG. 1 is configured to perform processing related to the cleaning process described above.

As schematically shown in FIG. 1 , the washing device 4 includes, for example, a washing tank 40, a heating unit 41 for heating the inside of the washing tank 40, and a temperature inside the washing tank 40. It has a temperature controller (not shown) that controls the temperature. In the washing device 4, the amount of ash in the finally obtained acrylic rubber bale can be effectively reduced by mixing the hydrous crumb produced in the coagulation device 3 with a large amount of water for washing.

The heating unit 41 of the cleaning device 4 is configured to heat the inside of the cleaning tank 40 . In addition, the temperature controller of the cleaning device 4 controls the heating operation by the heating unit 41 while monitoring the temperature inside the cleaning tub 40 measured by a thermometer, thereby controlling the temperature inside the cleaning tub 40. has been As described above, the temperature of the washing water in the washing tank 40 is usually 40°C or higher, preferably 40 to 100°C, more preferably 50 to 90°C, and most preferably 60 to 80°C. controlled so that

The water-containing crumb washed in the washing device 4 is supplied to the screw-type twin-screw extrusion dryer 5 that performs a dewatering step and a drying step. At this time, it is preferable that the water-containing crumb after washing is supplied to the screw-type twin-screw extrusion dryer 5 through a moisture remover 43 capable of separating free water. For the moisture remover 43, for example, a wire mesh, a screen, a rolling element, etc. can be used.

In addition, when the water-containing crumb after washing is supplied to the screw-type twin-screw extrusion dryer 5, the temperature of the water-containing crumb is preferably 40°C or higher, more preferably 60°C or higher. For example, the temperature of the water-containing crumb when supplied to the screw type twin-screw extrusion dryer 5 by setting the temperature of water used for washing with water in the washing device 4 to 60°C or higher (for example, 70°C). It may be maintained at 60 ° C. or higher, or it may be heated so that the temperature of the hydrous crumb is 40 ° C. or higher, preferably 60 ° C. or higher when conveying from the cleaning device 4 to the screw type twin screw extrusion dryer 5. . This makes it possible to effectively carry out the dewatering step and the drying step, which are the subsequent steps, and it becomes possible to significantly reduce the moisture content of the finally obtained dried rubber.

The screw-type twin-screw extrusion dryer 5 shown in FIG. 1 is configured to perform processing related to the dehydration step and the drying step described above. On the other hand, although a screw type twin screw extrusion dryer 5 is shown as a suitable example in FIG. 1, a centrifugal separator, a squeezer, etc. may be used as a dewatering machine for performing treatment related to the dehydration step, and to perform treatment related to the drying step As a dryer, you may use a hot air dryer, a vacuum dryer, an expander dryer, a kneader type dryer, etc.

The screw-type twin-screw extrusion dryer 5 is configured to mold and discharge dried rubber obtained through a dehydration step and a drying step into a predetermined shape. Specifically, the screw-type twin-screw extrusion dryer 5 has a dewatering barrel part 53 functioning as a dewatering machine for dewatering the water-containing crumb washed in the cleaning device 4 and a dryer function for drying the water-containing crumb. It is equipped with a drying barrel part 54, and furthermore, it is configured by providing a die 59 having a molding function for forming hydrous crumbs on the downstream side of the screw-type twin screw extrusion dryer 5.

Hereinafter, the structure of the screw type twin screw extrusion dryer 5 is demonstrated, referring FIG.

FIG. 2 shows the configuration of a specific example suitable for the screw type twin screw extrusion dryer 5 shown in FIG. 1 . With this screw-type twin-screw extrusion dryer 5, the above-described dehydration and drying steps can be suitably performed.

The screw-type twin-screw extrusion dryer 5 shown in FIG. 2 is a twin-screw type extrusion dryer comprising a pair of screws (not shown) in a barrel unit 51 . The screw-type twin-screw extrusion dryer 5 has a drive unit 50 that rotationally drives a pair of screws in a barrel unit 51 . With this configuration, it is suitable for drying by applying an optimal shear to acrylic rubber. The drive unit 50 is attached to the upstream end of the barrel unit 51 (the left end in FIG. 2 ). Further, the screw-type twin screw extrusion dryer 5 has a die 59 at the downstream end of the barrel unit 51 (right end in FIG. 2 ).

The barrel unit 51 has a supply barrel part 52, a dewatering barrel part 53, and a drying barrel part 54 from the upstream side to the downstream side (left to right in FIG. 2).

The supply barrel part 52 is comprised by two supply barrels, ie, the 1st supply barrel 52a and the 2nd supply barrel 52b.

In addition, the dewatering barrel part 53 is constituted by three dewatering barrels, that is, the first dewatering barrel 53a, the second dewatering barrel 53b, and the third dewatering barrel 53c.

In addition, the drying barrel portion 54 includes eight drying barrels, that is, a first drying barrel 54a, a second drying barrel 54b, a third drying barrel 54c, a fourth drying barrel 54d, and a second drying barrel 54b. It is comprised by the 5th dry barrel 54e, the 6th dry barrel 54f, the 7th dry barrel 54g, and the 8th dry barrel 54h.

In this way, the barrel unit 51 is configured by connecting each of the 13 divided barrels 52a to 52b, 53a to 53c, and 54a to 54h from the upstream side to the downstream side.

In addition, the screw-type twin-screw extrusion dryer 5 individually heats each of the barrels 52a to 52b, 53a to 53c, and 54a to 54h, so that each barrel 52a to 52b, 53a to 53c, and 54a to 54h It has a heating means (not shown) that heats the water-containing crumbs inside to a predetermined temperature. Heating means is provided with the number corresponding to each barrel 52a-52b, 53a-53c, and 54a-54h. As such a heating means, for example, a configuration in which high-temperature steam is supplied from a steam supply means to a steam distribution jacket formed in each of the barrels 52a to 52b, 53a to 53c, and 54a to 54h is employed. It doesn't work. In addition, the screw-type twin-screw extrusion dryer 5 has temperature control means (not shown) for controlling the set temperature of each heating means corresponding to each barrel 52a to 52b, 53a to 53c, and 54a to 54h.

On the other hand, the number of supply barrels, dewatering barrels, and drying barrels constituting each of the barrel parts 52, 53, and 54 in the barrel unit 51 is not limited to the embodiment shown in FIG. 2, and drying It can be set to a number according to the water content of the water-containing crumb of the acrylic rubber to be treated.

For example, the number of installation of the supply barrel of the supply barrel part 52 becomes 1-3, for example. The number of dewatering barrels installed in the dewatering barrel part 53 is preferably 2 to 10, for example, and 3 to 6 is more preferable because dehydration of the water-containing crumb of the adhesive acrylic rubber can be efficiently performed. . Moreover, as for the number of dry barrels installed in the dry barrel part 54, for example, it is preferable that it is 2-10 pieces, and it is more preferable in it being 3-8 pieces.

The pair of screws in the barrel unit 51 are rotationally driven by drive means such as a motor housed in the drive unit 50 . The pair of screws extend from the upstream side to the downstream side in the barrel unit 51, and by being driven to rotate, the water-containing crumb supplied to the supply barrel portion 52 can be conveyed to the downstream side while mixing. there is to be The pair of screws are preferably of a biaxially engaged type in which the ridge and valley portions are engaged with each other, whereby the dewatering efficiency and drying efficiency of the hydrous crumb can be increased.

Further, the rotational directions of the pair of screws may be the same or different, but from the viewpoint of self-cleaning performance, it is preferable that they rotate in the same direction. The screw shape of the pair of screws is not particularly limited, and any shape required for each of the barrel portions 52, 53, and 54 is sufficient and is not particularly limited.

The supply barrel portion 52 is an area for supplying water-containing crumbs into the barrel unit 51 . The 1st supply barrel 52a of the supply barrel part 52 has the feed opening 55 which supplies water-containing crumbs into the barrel unit 51.

The dewatering barrel part 53 is an area that separates and discharges a liquid (serum water) containing a coagulant or the like from the water-containing crumbs.

The first to third dewatering barrels 53a to 53c constituting the dewatering barrel part 53 each have dewatering slits 56a, 56b, and 56c for discharging moisture from the water-containing crumb to the outside. A plurality of dewatering slits 56a, 56b, and 56c are formed in each of the dewatering barrels 53a to 53c, respectively.

The slit width of each dewatering slit (56a, 56b, 56c), i.e., the size of the eyes, may be appropriately selected according to the conditions of use, and is usually 0.01 to 5 mm, with little loss of moistened crumbs, and efficient dewatering of moistened crumbs. From the viewpoint of being able to do it, it is preferably 0.1 to 1 mm, more preferably 0.2 to 0.6 mm.

Removal of moisture from the water-containing crumb in each dewatering barrel 53a to 53c of the dewatering barrel part 53 is carried out in the liquid phase from the respective dewatering slits 56a, 56b and 56c, and in the vapor phase. There are two cases of doing so. In the dewatering barrel part 53 of the present embodiment, the case where water is removed in the liquid phase is defined as drainage, and the case where water is removed in the vapor phase is defined as double steam.

In the dewatering barrel part 53, since it is possible to efficiently reduce the water content of the adhesive acrylic rubber by combining drainage and steam removal, it is suitable. In the dewatering barrel part 53, which dewatering barrel among the first to third dewatering barrels 53a to 53c is used to drain or double steam may be appropriately set according to the purpose of use. In the case of reducing the amount, the number of dewatering barrels for draining water may be increased. In that case, for example, as shown in FIG. 2 , drainage is performed by the first and second dewatering barrels 53a and 53b on the upstream side, and steam is doubled by the third dewatering barrel 53c on the downstream side. Further, for example, when the dewatering barrel part 53 has four dewatering barrels, for example, three dewatering barrels on the upstream side drain water, and one dewatering barrel on the downstream side performs steam doubling. can think of On the other hand, what is necessary is just to increase the number of dewatering barrels which double-steam, when reducing a water content.

The set temperature of the dewatering barrel part 53 is usually in the range of 60 to 150°C, preferably 70 to 140°C, and more preferably 80 to 130°C, as described in the dewatering/drying step described above, and drained water. The set temperature of the dewatering barrel for dehydration in the state is usually 60 ° C to 120 ° C, preferably 70 to 110 ° C, more preferably 80 to 100 ° C, and the set temperature of the dehydration barrel to dehydrate in the double steam state is usually It is the range of 100-150 degreeC, Preferably it is 105-140 degreeC, More preferably, it is 110-130 degreeC.

The drying barrel part 54 is an area for drying the dewatered crumb under reduced pressure. Among the first to eighth drying barrels 54a to 54h constituting the drying barrel part 54, the second drying barrel 54b, the fourth drying barrel 54d, the sixth drying barrel 54f, and the eighth drying barrel 54b. The drying barrel 54h has vent ports 58a, 58b, 58c, and 58d for degassing, respectively. Vent pipes (not shown) are respectively connected to the respective vent ports 58a, 58b, 58c, and 58d.

A vacuum pump (not shown) is connected to the end of each vent pipe, and the inside of the drying barrel part 54 is reduced to a predetermined pressure by the operation of the vacuum pump. The screw-type extruder 5 has a pressure control unit (not shown) that controls the degree of pressure reduction in the drying barrel part 54 by controlling the operation of these vacuum pumps.

The pressure reduction degree in the drying barrel part 54 may be appropriately selected, but as described above, it is usually set to 1 to 50 kPa, preferably 2 to 30 kPa, and more preferably 3 to 20 kPa.

In addition, the set temperature in the drying barrel part 54 may be appropriately selected, but as described above, it is usually set to 100 to 250°C, preferably 110 to 200°C, and more preferably 120 to 180°C.

In each of the drying barrels 54a to 54h constituting the drying barrel part 54, the set temperature in all the drying barrels 54a to 54h may be approximated or different, but the upstream side (dewatering barrel part 53 It is preferable to set the temperature on the downstream side (die 59 side) to a higher temperature than the temperature on the ) side) because the drying efficiency is improved.

The die 59 is a mold disposed at the downstream end of the barrel unit 51 and has a discharge port having a predetermined nozzle shape. Acrylic rubber dried in the drying barrel part 54 is extruded into a shape according to a predetermined nozzle shape by passing through the discharge port of the die 59 . The acrylic rubber passing through the die 59 can be molded into various shapes such as particulate, columnar, round rod, and sheet shapes depending on the nozzle shape of the die 59, but in the present invention, it is molded into a sheet shape. . Between the screw and the die 59, a breaker plate or wire mesh may or may not be provided.

The hydrous crumb of acrylic rubber obtained through the washing process is supplied to the supply barrel part 52 from the feed port 55 . The water-containing crumb supplied to the supply barrel part 52 is sent from the supply barrel part 52 to the dewatering barrel part 53 by rotation of a pair of screws in the barrel unit 51 . In the dewatering barrel part 53, as described above, drainage or double steam of water contained in the water-containing crumbs is discharged from the dewatering slits 56a, 56b, and 56c provided in the first to third dewatering barrels 53a to 53c, respectively. As a result, the water-containing crumb is dehydrated.

The water-containing crumb dewatered in the dewatering barrel part 53 is sent to the drying barrel part 54 by the rotation of a pair of screws in the barrel unit 51 . The water-containing crumb sent to the drying barrel part 54 is plasticized and mixed to become a melt, and is transported downstream while generating heat and raising the temperature. Then, the moisture contained in the acrylic rubber melt is vaporized, and the moisture (steam) is discharged to the outside through vent pipes (not shown) connected to the respective vent ports 58a, 58b, 58c, and 58d, respectively.

As described above, by passing through the drying barrel part 54, the water-containing crumb is dried and becomes a melt of acrylic rubber, and the acrylic rubber is supplied to the die 59 by the rotation of a pair of screws in the barrel unit 51, extruded from die 59.

Here, an example of the operating conditions of the screw-type twin-screw extrusion dryer 5 according to the present embodiment is given.

The number of rotations (N) of the pair of screws in the barrel unit 51 may be appropriately selected depending on various conditions, and is usually 10 to 1000 rpm, effectively reducing the water content of acrylic rubber and the amount of methyl ethyl ketone insoluble. In terms of reduction, it is preferably 50 to 750 rpm, more preferably 100 to 500 rpm, and most preferably 120 to 300 rpm.

In addition, the extrusion amount (Q) of the acrylic rubber is not particularly limited, but is usually 100 to 1500 kg/hr, preferably 300 to 1200 kg/hr, more preferably 400 to 1000 kg/hr, 500 to 800 kg/hr is most preferred.

The ratio (Q/N) between the amount of extrusion (Q) of the acrylic rubber and the number of revolutions (N) of the screw (Q/N) is not particularly limited, but is usually 1 to 20, preferably 2 to 10, more preferably 3 to 8, with 4 to 6 being particularly preferred.

The maximum torque in the barrel unit 51 is not particularly limited, but is usually 5 to 125 N m, preferably 10 to 100 N m, more preferably 10 to 50 N m, and particularly preferably 15 N m. ~ 45 N m.

The specific power in the barrel unit 51 is not particularly limited, but is usually 0.01 to 0.3 [kw h/kg] or more, preferably 0.05 to 0.25 [kw h/kg], more preferably 0.1 to 0.2 [kw h/kg]. kw·h/kg].

The specific power in the barrel unit 51 is not particularly limited, but is usually 0.1 to 0.6 [A h/kg] or more, preferably 0.15 to 0.55 [A h/kg], more preferably 0.2 to 0.5 [A h/kg]. A h/kg].

The shear rate in the barrel unit 51 is not particularly limited, but is usually 5 to 150 [1/s] or more, preferably 10 to 100 [1/s], more preferably 25 to 75 [1/s]. is the range of

The shear viscosity of the acrylic rubber in the barrel unit 51 is not particularly limited, but is usually 4000 to 8000 [Pa s] or less, preferably 4500 to 7500 [Pa s], more preferably 5000 to 7000 [Pa s]. s] range.

The cooling device 6 shown in FIG. 1 is configured to cool dry rubber obtained through a dehydration step by a dehydrator and a drying step by a dryer. As a cooling method by the cooling device 6, it is possible to employ various methods including an air cooling method under blowing or air conditioning, a splashing method in which water is sprayed, an immersion method in which water is immersed, and the like. Alternatively, the dry rubber may be cooled by leaving it at room temperature.

As described above, depending on the nozzle shape of the die 59, the dry rubber discharged from the screw extruder 5 is extruded into various shapes such as particulate, columnar, round bar, and sheet shapes. In the case, it is molded into a sheet shape. Hereinafter, referring to FIG. 3, as an example of the cooling device 6, a transport type cooling device 60 that cools the sheet-shaped dry rubber 10 molded into a sheet shape will be described.

FIG. 3 shows the configuration of a transport type cooling device 60 suitable as the cooling device 6 shown in FIG. 1 . The conveying type cooling device 60 shown in FIG. 3 is configured to cool the sheet-shaped dry rubber 10 discharged from the discharge port of the die 59 of the screw extruder 5 by an air cooling method while conveying it. By using this transport type cooling device 60, the sheet-shaped dry rubber discharged from the screw extruder 5 can be appropriately cooled.

The transport type cooling device 60 shown in FIG. 3 is directly connected to the die 59 of the screw type extruder 5 shown in FIG. 2, or installed near the die 59 and used, for example.

The conveying type cooling device 60 includes a conveyor 61 for conveying the sheet-shaped dry rubber 10 discharged from the die 59 of the screw extruder 5 in the direction of arrow A in FIG. 3, and the conveyor 61 ) has a cooling means 65 for blowing cold air to the sheet-shaped dry rubber 10.

The conveyor 61 has rollers 62 and 63 and a conveyor belt 64 that is wound around the rollers 62 and 63 and on which the sheet-shaped dry rubber 10 is placed. The conveyor 61 is configured to continuously convey the sheet-shaped dry rubber 10 discharged from the die 59 of the screw extruder 5 on the conveyor belt 64 to the downstream side (right side in FIG. 3). there is.

The cooling means 65 is not particularly limited, but is configured to, for example, blow cooling air sent from a cooling air generating means (not shown) onto the surface of the sheet-shaped dry rubber 10 on the conveyor belt 64. Having a , etc. can be mentioned.

The length L1 of the conveyor 61 and the cooling means 65 of the transport type cooling device 60 (the length of the portion where cooling wind can be blown) is not particularly limited, but is, for example, 10 to 100 m, preferably. 20 to 50 m. In addition, the conveyance speed of the sheet-shaped dry rubber 10 in the conveying type cooling device 60 is the length L1 of the conveyor 61 and the cooling means 65 and the die 59 of the screw extruder 5 What is necessary is just to adjust suitably according to the discharge rate of the sheet-like dry rubber 10 discharged|emitted from, a target cooling rate, cooling time, etc., For example, it is 10-100 m/hr, More preferably, it is 15-70 m/hr am.

According to the transport type cooling device 60 shown in FIG. 3 , while conveying the sheet-like dry rubber 10 discharged from the die 59 of the screw extruder 5 by the conveyor 61, the sheet-like dry rubber 10 The sheet-shaped dry rubber 10 is cooled by blowing cooling air from the cooling means 65 to the .

On the other hand, the conveying type cooling device 60 is not particularly limited to a configuration including one conveyor 61 and one cooling means 65 as shown in FIG. 3, and two or more conveyors 61 and this It is good also as a structure provided with the corresponding two or more cooling means 65. In that case, what is necessary is just to make the total length of each of two or more conveyors 61 and cooling means 65 into the said range.

The baling device 7 shown in FIG. 1 is configured to process dry rubber that has been extruded from the screw extruder 5 and cooled in the cooling device 6 to produce a bale, which is a block. As described above, the screw extruder 5 can extrude dry rubber into various shapes such as particulate, columnar, round bar, and sheet shapes, and the baling device 7 has various shapes in this way. It is configured to bale the molded dry rubber. The weight and shape of the veiled acrylic rubber produced by the baling device 7 are not particularly limited, but, for example, about 20 kg of substantially rectangular parallelepiped veiled acrylic rubber is produced.

The baling device 7 may be provided with a baler, for example, and may manufacture the bale-like acrylic rubber by compressing the cooled dry rubber with the baler.

In addition, when the sheet-like dry rubber 10 is manufactured by the screw extruder 5, you may manufacture the veil-like acrylic rubber in which the sheet-like dry rubber 10 was laminated|stacked. For example, a cutting mechanism for cutting the sheet-shaped dry rubber 10 may be installed in the baling device 7 arranged on the downstream side of the transport type cooling device 60 shown in FIG. 3 . Specifically, the cutting mechanism of the baling device 7 continuously cuts the cooled sheet-like dry rubber 10 at predetermined intervals, for example, to cut sheet-like dry rubber 16 of a predetermined size. It is configured to be processed into. By laminating a plurality of sheets of cut sheet-shaped dry rubber 16 cut into a predetermined size by a cutting mechanism, a veil-like acrylic rubber in which cut sheet-shaped dry rubber 16 is laminated can be produced.

In the case of producing a veil-like acrylic rubber in which the cut sheet-like dry rubber 16 is laminated, it is preferable to laminate the cut sheet-like dry rubber 16 at 40°C or higher, for example. By laminating the cut sheet-like dry rubber 16 at 40°C or higher, good air bleeding is realized by additional cooling and compression by its own weight.

Example

Below, examples and comparative examples will be given to explain the present invention in more detail. "Part", "%", and "ratio" in each case are based on weight unless otherwise specified. On the other hand, various physical properties were evaluated according to the following methods.

[monomer composition]

Regarding the monomer composition of the acrylic rubber, the monomer constitution of each monomer unit in the acrylic rubber was confirmed by ¹ H-NMR, and the activity of the reactive group remaining in the acrylic rubber and the content of each reactive group were determined by the following method. Confirmed. In addition, the content ratio of each monomeric unit in acrylic rubber was computed from the usage-amount and polymerization conversion ratio used for the polymerization reaction of each monomer. Specifically, the polymerization reaction was an emulsion polymerization reaction, and since the polymerization conversion rate was approximately 100%, which could not confirm any unreacted monomers, the content ratio of each monomer unit in the rubber was the same as the amount of each monomer used. .

[Reactive group content]

The content of the reactive group in the acrylic rubber veil was measured by the following method.

(1) The amount of carboxyl groups was calculated by dissolving a sample (acrylic rubber veil) in acetone and performing potentiometric titration with a potassium hydroxide solution.

(2) The amount of epoxy groups was calculated by dissolving the sample in methyl ethyl ketone, adding a prescribed amount of hydrochloric acid thereto to react with epoxy groups, and titrating the remaining amount of hydrochloric acid with potassium hydroxide.

(3) The amount of chlorine was calculated by completely burning a sample in a combustion flask, absorbing generated chlorine into water, and titrating with silver nitrate.

[Ashes amount]

The ash content (%) contained in the acrylic rubber veil was measured according to JIS K6228 A method.

[Ashes component amount]

For the amount (%) of each component in the acrylic rubber veil ash, the ash collected at the time of measuring the ash amount was pressed on a suitable filter paper of Φ 20 mm, and the component amount (ppm) was measured by XRF using ZSX Primus (manufactured by Rigaku), It was calculated as a ratio in the ash.

[Molecular weight and molecular weight distribution]

Molecular weight (Mw, Mn, Mz) and molecular weight distribution (Mw/Mn and Mz/Mw) of acrylic rubber were determined by adding 0.05 mol/L of lithium chloride and 0.01% of 37% concentrated hydrochloric acid to dimethylformamide as a solvent, respectively. Absolute molecular weight and absolute molecular weight distribution measured by the GPC-MALS method using the Here, the "GPC-MALS method" is the following content. GPC (gel permeation chromatography) method is a type of liquid chromatography that separates based on differences in molecular size. Specifically, GPC (Gel Permeation Chromatography) uses a multi-angle laser light scattering photometer (MALS) and differential refractive index By combining the system (RI) and measuring the light scattering intensity and refractive index difference of the molecular chain solution size-classified by the GPC device according to the melting time, the molecular weight of the solute and its content are sequentially calculated, and finally, the polymer material It is a method for obtaining the absolute molecular weight distribution and absolute average molecular weight value of

The composition of this apparatus, the gel permeation chromatography multi-angle light scattering photometer, is a pump (LC-20ADopt manufactured by Shimadzu Corporation), a differential refractometer (Optilab rEX Wyatt Technology) as a detector, and a multi-angle light scattering detector (DAWN HELEOS Wyatt manufactured by Technology).

In this way, the molecular weight of the solute and its content were sequentially calculated and obtained. The measurement conditions and measurement method by the GPC device are as follows.

Column: 2 TSKgel α-M (Φ 7.8 mm × 30 cm, manufactured by Tosoh Corporation)

Column temperature: 40°C

Flow rate: 0.8 ml/mm

Sample preparation: 5 ml of solvent was added to 10 mg of rubber sample, and gently stirred at room temperature (dissolution was observed). After that, filtration was performed using a 0.5 μm filter.

[Glass Transition Temperature (Tg)]

The glass transition temperature (Tg) of the acrylic rubber was measured using a differential scanning calorimeter (DSC, product name "X-DSC7000", manufactured by Hitachi High-Tech Science Co., Ltd.).

[gel amount]

The gel amount (%) of the acrylic rubber veil was determined by the following method as the amount of insoluble content in methyl ethyl ketone.

About 0.2 g of acrylic rubber veil was weighed (Xg), immersed in 100 ml of methyl ethyl ketone, left at room temperature for 24 hours, and then the filtrate obtained by filtering the insoluble content of methyl ethyl ketone using an 80 mesh wire mesh, that is, The dry solid content (Yg) obtained by evaporating and drying the filtrate in which only the rubber component dissolved in methyl ethyl ketone was dissolved was solidified was weighed and calculated by the following formula.

Gel amount (%) = 100 × (X-Y) / X

[importance]

The specific gravity of the acrylic rubber veil was measured according to JIS K6268 Crosslinked Rubber - Method A of Density Measurement.

The measured value obtained by the following measurement method is density, and the density of water is set to 1 Mg/m ³ to be specific gravity. Specifically, the specific gravity of a rubber sample obtained according to JIS K6268 Crosslinked Rubber - Method A of Density Measurement is obtained by dividing the mass by the volume containing the voids of the rubber sample, according to JIS K6268 Crosslinked Rubber - Method A of Density Measurement It is obtained by dividing the density of the rubber sample to be measured by the density of water (if the density of the rubber sample is divided by the density of water, the numerical value is the same and the unit is lost). Specifically, the specific gravity of the rubber sample is obtained based on the following procedure.

(1) Cut a 2.5 g test piece from a rubber sample left at standard temperature (23°C ± 2°C) for at least 3 hours, and use a thin nylon thread with a mass of less than 0.010 g from a hook on a chemical balance with a precision of 1 mg to test the test piece. Suspend so that the base of is 25 mm above the distribution dish for chemical balance, and measure the mass (m1) of the test piece in the air to mg twice.

(2) Next, fill a beaker with a capacity of 250 cm ³ placed on a distribution dish for chemical balance with distilled water cooled to a standard temperature after boiling, immerse the test piece in it, remove air bubbles adhering to the surface of the test piece, , Observe the movement of the pointer of the balance for several seconds, confirm that the pointer does not slowly shake due to convection, and measure the mass (m2) of the test piece in water twice in mg unit.

(3) In addition, when the density of the test piece is less than 1 Mg/m ³ (when the test piece floats in water), a weight is attached to the test piece, and the mass of the weight in water (m3) and the mass of the test piece and weight (m4 ) is measured in mg units twice.

(4) For the specific gravity of the rubber sample, the density (Mg/m ³ ) was calculated based on the following formula using the average value of m1, m2, m3, and m4 measured above, and the calculated density was the density of water (1.00 Mg /m ³ ) to get the result.

(Density of rubber sample when weight is not used)

Density = m1/(m1 - m2)

(Density of rubber sample when weight is used)

Density = m1/(m1 + m3 - m4)

[Moisture content]

Water content (%) was measured according to JIS K6238-1: Oven A (Volatile Content Measurement) method.

[pH]

pH was measured with a pH electrode after dissolving 6 g (±0.05 g) of acrylic rubber with 100 g of tetrahydrofuran, adding 2.0 ml of distilled water to confirm complete dissolution.

[Complex Viscosity]

For the complex viscosity η, the temperature dispersion (40 to 120 ° C.) was measured at a strain of 473% and 1 Hz using a dynamic viscoelasticity measuring device “Rubber Process Analyzer RPA-2000” (manufactured by Alpha Technologies), and at each temperature The complex viscosity η of was obtained. Here, among the dynamic viscoelastic properties described above, the dynamic viscoelasticity at 60 ° C is taken as the complex viscosity η (60 ° C), and the dynamic viscoelasticity at 100 ° C is taken as the complex viscosity η (100 ° C), and its ratio η (100 ° C) The value of /η (60°C) was calculated.

[Mooney viscosity (ML ₁₊₄ , 100°C)]

The Mooney viscosity (ML ₁₊₄ , 100°C) was measured according to the JIS K6300 uncrosslinked rubber physical test method.

[Injection moldability]

The injection moldability was observed and scored for shape formability, releasability, and fuseability using a small injection molding machine (SLIM15-30: manufactured by Daihan Co., Ltd.), and comprehensively evaluated by the sum of these according to the following criteria. For shape formation and releasability, a mold imitating three cylindrical shapes (A: 4 mmΦ, B: 3 mmΦ, C: 2 mmΦ) of different diameters with an axis length of more than 150 mm was prepared, and a screw temperature of 90 ° C. and an injection time of 30 seconds were used in this mold. , The rubber composition was introduced under the conditions of an injection pressure of 7 MPa, and after crosslinking at a mold temperature of 170 ° C. for 1 minute and 30 seconds, the injection-molded cylindrical molding was taken out, and the cylindrical molding and mold were observed and scored according to the following criteria. . For fusion, a mold imitating a fusion observation body having a thickness of 0.5 mm × width of 5 mm × length of 40 mm with 5 mm Φ pipes connected to both ends in the longitudinal direction is prepared, and a screw temperature of 90 The rubber composition was introduced under the conditions of °C, injection time of 30 seconds, and injection pressure of 7 MPa, and after crosslinking at a mold temperature of 170 °C for 1 minute and 30 seconds, the fusion state of the rubber composition in the fusion observer was observed and scored according to the following criteria. did

(Shape Formability)

5 points: In all of A, B, and C, cylindrical moldings can be produced, and in all of them, the shape of the tip of the molding is completely followed by the mold, and no burr formation is observed.

4 points: In all of A, B, and C, it is possible to produce a cylindrical molded product, but in C, only a small part of the tip of the molded product cannot completely follow the shape of the mold.

3 points: Cylinder-shaped moldings can be manufactured in A and B, and more than half of the moldings can be manufactured in C.

2 points: Cylinder-shaped moldings can be produced in A and B, but less than half of the moldings are produced in C.

1 point: A molding can be produced in A, but a molding is not completely formed in B.

0 point: Unable to produce moldings from A

(dysplasia)

5 points: Easy release from the mold and no mold residue

4 points: It can be easily released from the mold, but very small mold residues are observed.

3 points: Easy release from mold, but slight mold residue

2 points: It is difficult to remove from the mold slightly, but there is no mold residue.

1 point: It is difficult to remove from the mold slightly, and there are mold residues.

0 points: difficult to remove from the mold

(convergence)

5 points: complete fusion

0 point: incomplete fusion (poor fusion)

comprehensive evaluation

◎: perfect score (15 points)

○: 14 points

□: 13 points

△: 11 to 12 points

×: 10 points or less

[Banbury machinability]

The Banbury processability of the rubber sample was determined by putting the rubber sample into a Banbury mixer heated to 50 ° C., mixing it for 1 minute, and then adding the compounding agent A of the rubber mixture formulation shown in Table 1 to integrate the rubber mixture in the first stage. The time until the maximum torque value is displayed, that is, BIT (Black Incorporation Time) was measured, and an index with Comparative Example 2 set to 100 was calculated and evaluated according to the following criteria.

◎: 20 or less

○: more than 20 and less than 40

□: more than 40 and less than 60

△: more than 60 and less than or equal to 80

×: exceeds 80

[Storage stability evaluation]

For the storage stability of the rubber sample, the rubber sample was put into a constant temperature and humidity bath (SH-222 manufactured by ESPEC) at 45 ° C. × 80% RH, and the rate of change in water content before and after the test for 7 days was calculated, and Comparative Example 2 was 100 An index to be calculated was evaluated according to the following criteria.

◎: 20 or less

○: more than 20 and less than 50

□: more than 50 and less than 90

△: more than 90 and less than 100

×: exceeds 100

[Water resistance evaluation]

The water resistance of the rubber sample was tested by immersing the crosslinked product of the rubber sample in distilled water at a temperature of 85 ° C. for 100 hours in accordance with JIS K6258, measuring the volume change rate before and after immersion, and taking Comparative Example 2 as 100. It was calculated and evaluated according to the following criteria.

◎: 1 or less

○: more than 1 and less than or equal to 5

□: more than 5 and less than 10

△: more than 10 and less than 50

×: exceeds 50

[Compression permanent deformation resistance]

The compression set resistance of the rubber sample was evaluated according to the following criteria by measuring the compression set after being placed at 175° C. for 90 hours in a state in which the rubber crosslinked product of the rubber sample was compressed by 25% according to JIS K6262.

◎: compression set is less than 15%

×: compression set is 15% or more

[State physical property evaluation]

The state physical properties of the rubber sample were evaluated according to the following criteria by measuring the breaking strength, 100% tensile stress, and elongation at break of the rubber cross-linked product of the rubber sample according to JIS K6251.

(1) Breaking strength evaluated 10 MPa or more as (double-circle) and less than 10 MPa as x.

(2) The 100% tensile stress was evaluated by denoting 5 MPa or more as ◎ and less than 5 MPa as ×.

(3) Elongation at break was evaluated by setting 150% or more as ◎ and less than 150% as ×.

[Evaluation of variance in gel amount]

To evaluate the deviation of the gel amount of the rubber sample, the gel amount of 20 points randomly selected from 20 parts (20 kg) of the rubber sample was measured and evaluated based on the following criteria.

◎: Calculate the average value of the amount of gel at 20 measured points, and all 20 measured points are within the range of the average value ± 3

○: The average value of the gel amount of 20 measured points was calculated, and all of the 20 measured points were within the range of the average value ± 5 (even one point out of the 20 points measured in the range of the average value ± 3 would deviate, but the average value ± All 20 points are within the range of 5)

×: Calculate the average value of the amount of gel at 20 measured points, and even 1 point out of the 20 points measured from the range of the average value ± 5

[Evaluation of Processing Stability by Mooney Scorch Suppression]

The cooling rate of the sheet-like acrylic rubber extruded from the screw-type twin-screw extrusion dryer described in Japanese Patent No. 6683189 and the Mooney scorch storage stability of the acrylic rubber composition were evaluated.

[Example 1]

As shown in Table 2-1, in a mixing vessel equipped with a homomixer, 46 parts of pure water, 48.5 parts of ethyl acrylate as monomer components, 50 parts of n-butyl acrylate and 1.5 parts of monon-butyl fumarate, and tridecyl as an emulsifier 1.8 parts of oxyhexaoxyethylene phosphate sodium salt was added and stirred to obtain a monomer emulsion.

170 parts of pure water and 3 parts of the monomer emulsion obtained above were put into a polymerization reactor equipped with a thermometer and a stirring device, and after cooling to 12° C. under a nitrogen stream, 0.00033 part of ferrous sulfate, 0.02 part of sodium ascorbate, and organic A polymerization reaction was initiated by adding 0.0045 parts of diisopropylbenzene hydroperoxide as a radical generator. The temperature in the polymerization reactor was maintained at 23°C, and the remainder of the monomer emulsion was continuously added dropwise over 3 hours, 0.012 part of n-dodecylmercaptan after 50 minutes from the start of the reaction, 0.012 part of n-dodecylmercaptan after 100 minutes, and 120 minutes later, 0.4 part of sodium L-ascorbate was added to continue the polymerization reaction, and when the polymerization conversion ratio reached approximately 100%, hydroquinone as a polymerization terminator was added to stop the polymerization reaction to obtain an emulsion polymerization liquid. .

Subsequently, in a coagulation bath equipped with a thermometer and a stirring device, it was heated to 80° C. and vigorously stirred at 600 revolutions of the stirring blades (circumferential speed: 3.1 m/s) of the stirring device. A 2% aqueous solution of magnesium sulfate (sulfuric acid as a coagulant) In 350 parts of a coagulation solution using magnesium), the obtained emulsion polymerization solution was heated to 80°C and continuously added to coagulate the polymer, thereby obtaining a coagulation slurry containing acrylic rubber crumb and water as a coagulation product. Water-containing crumb was obtained by draining water from the coagulated layer while separating the crumb from the obtained slurry by filtration.

194 parts of hot water (70℃) was added to the coagulation tank where the filtered and separated hydrous crumbs remained, stirred for 15 minutes to wash the water-containing crumbs, and then the moisture was discharged. The water-containing crumbs were washed (the total number of washings was twice). The washed hydrous crumb (hydrous crumb temperature: 65°C) was supplied to the screw-type twin-screw extrusion dryer 5, and dehydrated and dried to extrude sheet-like dried rubber with a width of 300 mm and a thickness of 10 mm. Next, the sheet-shaped dried rubber was cooled at a cooling rate of 200°C/hr using a transport type cooling device connected directly to the screw type twin screw extrusion dryer 5 and installed.

On the other hand, the screw-type twin-screw extrusion dryer used in Example 1 is composed of one supply barrel, three dewatering barrels (first to third dehydration barrels), and five drying barrels (first to fifth drying barrels). has been The first dewatering barrel drains water, and the second and third dewatering barrels drain steam. The operating conditions of the screw-type twin-screw extrusion dryer were as follows. Table 2-1 shows the water content, maximum torque, specific power, specific power, shear rate, and shear viscosity after dehydration (drainage) of the screw-type twin-screw extrusion dryer.

Water content:

Moisture content of hydrous crumb after draining from the first dewatering barrel: 20%

Moisture content of hydrous crumb after doubling in the third dewatering barrel: 10%

Moisture content of hydrous crumb after drying in the fifth drying barrel: 0.4%

rubber temperature:

·Temperature of water-containing crumb supplied to the supply barrel: 65℃

・Temperature of rubber discharged from screw type twin screw extrusion dryer: 140°C

Set temperature for each barrel:

1st dewatering barrel: 100℃

2nd dewatering barrel: 120℃

3rd dewatering barrel: 120℃

1st drying barrel: 120 ℃

2nd drying barrel: 130 ℃

3rd drying barrel: 140 ℃

4th drying barrel: 160 ℃

5th drying barrel: 180 ℃

Driving conditions:

Diameter of screw (D): 132mm

·Overall length of screw (L): 4620mm

·L/D: 35

Rotational speed of screw: 135 rpm

Decompression degree of drying barrel: 10 kPa

Amount of rubber extruded from the die: 700 kg/hr

Resin pressure in die: 2 MPa

·Maximum torque in the screw type twin screw extrusion dryer: 40 N·m

After cooling the extruded sheet-like dry rubber to 50°C, it was cut with a cutter and laminated so as to make 20 parts (20 kg) while not reaching 40°C or lower to obtain an acrylic rubber veil (A). The reactive group content, ash content, ash component amount, gel amount, pH, specific gravity, glass transition temperature (Tg), water content, molecular weight, molecular weight distribution, and complex viscosity at 100 ° C and 60 ° C of the obtained acrylic rubber veil (A) were measured. and shown in Table 2-2. In addition, the storage stability test of the acrylic rubber veil (A) was performed to determine the rate of change in water content, and the results are shown in Table 2-2.

Then, using a Banbury mixer, 100 parts of the acrylic rubber veil (A) and the compounding agent A of “Formulation 1” shown in Table 1 were charged, and mixed at 50° C. for 5 minutes (first stage mixing). At this time, BIT was measured to evaluate Banbury workability, and the results are shown in Table 2-2. Next, the obtained mixture was transferred to a roll at 50°C, and compounding agent B of "Formulation 1" shown in Table 1 was blended and mixed (second stage mixing) to obtain a rubber composition. The injection moldability of the resulting rubber composition was evaluated, and the results are shown in Table 2-2.

[Table 1]

Then, the residual 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 primary crosslinking was performed by pressing at 180° C. for 10 minutes while pressurizing with a press pressure of 10 MPa. A sheet-like cross-linked rubber was obtained by further heating in an oven for 2 hours and secondary cross-linking. Then, a test piece of 3 cm × 2 cm × 0.2 cm was cut out from the obtained cross-linked rubber in the form of a sheet, and water resistance, compression set resistance, and normal physical properties were evaluated. Their results are shown in Table 2-2.

[Example 2]

As shown in Table 2-1, an acrylic rubber veil (B) was prepared in the same manner as in Example 1 except that the monomer components were changed to 48.25 parts of ethyl acrylate, 50 parts of n-butyl acrylate, and 1.75 parts of monon-butyl fumarate. was obtained and evaluated for each characteristic (the formulation was changed to “Formulation 2” (see Table 1)). Their results are shown in Table 2-2.

[Example 3]

An acrylic rubber veil (C) was performed in the same manner as in Example 1 except that the post-addition of n-dodecylmercaptan was changed three times: 0.008 parts after 50 minutes, 0.008 parts after 100 minutes, and 0.008 parts after 120 minutes. obtained and evaluated each characteristic. Their results are shown in Table 2-2.

[Example 4]

An acrylic rubber veil (D) was obtained in the same manner as in Example 2 except that the post-addition of n-dodecylmercaptan was changed three times: 0.008 parts after 50 minutes, 0.008 parts after 100 minutes, and 0.008 parts after 120 minutes. obtained and evaluated each characteristic. Their results are shown in Table 2-2.

[Example 5]

As shown in Table 2-1, an acrylic rubber veil (E) was obtained and each property was evaluated in the same manner as in Example 1 except that the maximum torque of the screw type twin screw extrusion dryer was changed to 15 N·m. Their results are shown in Table 2-2.

[Example 6]

An acrylic rubber veil (F) was obtained and its properties were evaluated in the same manner as in Example 2, except that the maximum torque of the screw-type twin-screw extrusion dryer was changed to 15 N·m. Their results are shown in Table 2-2.

[Example 7]

An acrylic rubber veil (G) was obtained and its properties were evaluated in the same manner as in Example 5, except that the water content after dewatering in the dewatering barrel of the screw-type twin-screw extrusion dryer was 30% by weight. Their results are shown in Table 2-2.

[Example 8]

An acrylic rubber veil (H) was obtained and its properties were evaluated in the same manner as in Example 6, except that the water content after dewatering in the dewatering barrel of the screw-type twin-screw extrusion dryer was 30% by weight. Their results are shown in Table 2-2.

[Reference Example 1]

After washing, the water-containing crumb is dried to a water content of 0.4% using a hot air dryer at 160°C to obtain crumb-like acrylic rubber (I), which is then filled into a 300 × 650 × 300 mm baler and compacted for 25 seconds at a pressure of 3 MPa. An acrylic rubber veil (I) was obtained in the same manner as in Example 2, except that ordinary acrylic rubber was used. Each property of the acrylic rubber veil was evaluated, and their results are shown in Table 2-2.

[Reference Example 2]

Acrylic rubber A veil (J) was obtained and each characteristic (the compounding agent was changed to "Formulation 3" (see Table 1)) was evaluated. Their results are shown in Table 2-2.

[Reference Example 3]

An acrylic rubber veil ( K) was obtained and each characteristic (the compounding agent was changed to “Formulation 4” (see Table 1)) was evaluated. Their results are shown in Table 2-2.

[Reference Example 4]

An acrylic rubber veil (L) was obtained in the same manner as in Reference Example 3 except that the post-addition of n-dodecylmercaptan was changed three times: 0.008 parts after 50 minutes, 0.008 parts after 100 minutes, and 0.008 parts after 120 minutes. obtained and evaluated each characteristic. Their results are shown in Table 2-2.

[Reference Example 5]

An acrylic rubber veil (M) was obtained in the same manner as in Reference Example 3 except that diisopropylbenzene hydroperoxide was changed to 0.0048 parts, and 0.024 parts of n-dodecylmercaptan was continuously added to the monomer emulsion without subsequent addition. Each property was evaluated. Their results are shown in Table 2-2.

[Comparative Example 1]

The coagulation reaction was performed by adding 0.7% magnesium sulfate aqueous solution to the agitated emulsion polymerization solution after emulsion polymerization (stirring water: 100 rpm, circumferential speed: 0.5 m/s), and further, without baling with a baler, crumb-like acrylic rubber. A crumb-like acrylic rubber (N) was obtained in the same manner as in Reference Example 5 except for obtaining, and each property was evaluated. Their results are shown in Table 2-2.

[Comparative Example 2]

A crumb-like acrylic rubber (0) was obtained and its properties were evaluated in the same manner as in Comparative Example 1 except that diisopropylbenzene hydroperoxide was changed to 0.005 part and no chain transfer agent was added. Their results are shown in Table 2-2.

[Table 2-1]

[Table 2-2]

From Table 2-2, it is made of the acrylic rubber having an ion-reactive group of the present invention, and the gel amount of the methyl ethyl ketone insoluble content is 15% by weight or less, and all values randomly measured at 20 points are in the range of (average value ± 5)% by weight Acrylic rubber veils (A) to (H) having a pH of 6 or less, an ash content of 0.0005% by weight or more and 0.2% by weight or less, and a total amount of sodium, sulfur, calcium, magnesium, and phosphorus in the ash of 90% by weight or more , it can be seen that the state physical properties including Banbury processability, water resistance, compression set resistance, and strength properties are excellent, and also excellent in injection moldability and storage stability (Examples 1 to 8).

From Table 2-2, the acrylic rubber veils (A) to (M) and the crumb-like acrylic rubbers (N) to (O) of Examples and Reference Examples of the present application have carboxyl groups, epoxy groups, or ion reactive groups of chlorine atoms, It can be seen that the compression set properties are excellent, and since the number average molecular weight (Mn) exceeds 500,000 and the weight average molecular weight (Mw) far exceeds 1,000,000, the state physical properties including strength properties are also excellent (Example Examples 1 to 8, Reference Examples 1 to 5, and Comparative Examples 1 to 2). However, crumb-like acrylic rubbers (N) to (O) are inferior in Banbury processability, injection moldability, water resistance, and storage stability (Comparative Examples 1 to 2).

From Tables 2-1 and 2-2, it can be seen that the Banbury processability is correlated with the gel amount of the methyl ethyl ketone insoluble component (Examples 1 to 8, Reference Examples 1 to 5 and Comparative Examples 1 to 2 comparison with). The gel amount of the methyl ethyl ketone insoluble content of acrylic rubber can be reduced by emulsion polymerization in the presence of a chain transfer agent (Comparison of Reference Examples 1 to 5 and Comparative Examples 1 and 2). In particular, methyl ethyl ketone insoluble content Since the amount of gel increases rapidly when the polymerization conversion is increased to increase the strength characteristics, in Reference Examples 1 to 5 of post-addition of the chain transfer agent in the latter half of the polymerization reaction, the gel formation of methyl ethyl ketone insoluble components can be suppressed. Able to know. The gel amount of the acrylic rubber veil is also significantly reduced by extruding and drying the hydrous crumb in a molten state with a moisture content of less than 1% by weight and substantially containing no water in a screw-type twin screw extrusion dryer. Banbury processability is significantly improved without impairing the strength characteristics of the veil (comparison of Examples 1 to 8 and Reference Examples 1 to 5). In the present invention, although not shown in this Example, the gel amount of the methyl ethyl ketone insoluble matter rapidly increased in emulsion polymerization without adding a chain transfer agent (Comparative Examples 1 and 2), in a screw-type twin-screw extrusion dryer, was substantially It has been confirmed that it is lost by melting and kneading in a water-free state (moisture content less than 1% by weight), and the Banbury workability can be greatly improved.

From Table 2-2, with respect to water resistance, the acrylic rubber veils (A) to (H) of the present invention are excellent (Comparison of Examples 1 to 8, Reference Examples 1 to 5 and Comparative Examples 1 to 2), Among them, in the order of acrylic rubber veils (A) to (F) > acrylic rubber veils (G) to (H) > acrylic rubber veils (I) to (J) > acrylic rubber veils (K) to (M), especially It can be seen that the acrylic rubber veils (A) to (F) are remarkably excellent (comparison among Examples 1 to 8 and Reference Examples 1 to 5), and that they are greatly affected by the amount of ash in the acrylic rubber ( Comparison among Examples 1 to 8, Reference Examples 1 to 5 and Comparative Examples 1 to 2).

From Tables 2-1 and 2-2, the amount of ash in the acrylic rubber bale was changed to a method in which the coagulation solution concentration was increased (2%) in the coagulation reaction and the emulsion polymerization solution was added to the stirring coagulation solution ( Lx↓), and further, it can be seen that the weight loss can be greatly reduced by vigorously stirring the coagulating solution (agitation water: 600 rpm/circumferential speed: 3.1 m/s) (comparison between Reference Examples 1 to 5 and Comparative Example 1) . In particular, the coagulation reaction is performed by adding the emulsion polymerization solution in the coagulation solution that is stirred very vigorously, and the data will be described later. It is presumed that, as a result, the washing efficiency with hot water and the removal efficiency of the emulsifier or coagulant during dehydration are remarkably improved, thereby reducing the amount of ash in the acrylic rubber veil and remarkably improving the water resistance. In addition, with respect to water resistance, it can be seen that the acrylic rubber veils (I) to (J) are superior to the acrylic rubber veils (K) to (M) in Reference Examples 1 to 5, while the amount of ash is about the same. This shows that, in terms of water resistance, among ion-reactive groups, acrylic rubber veils having carboxyl groups or epoxy groups are superior to chlorine atoms (comparison of Reference Examples 1 to 2 and Reference Examples 3 to 5).

From Tables 2-1 and 2-2, further, with respect to water resistance, by dehydrating (squeezing out moisture) the hydrous crumb before drying, the amount of ash in the acrylic rubber veil is further greatly reduced and the water resistance is remarkably improved. (Comparison of Examples 1 to 8 and Reference Examples 1 to 5), and squeezing out more water from the hydrous crumb, such that the water content after dehydration is 20% rather than 30%, reduces the amount of ash and significantly improves the water resistance of the acrylic rubber veil. It turns out that improvement can be made (comparison of Examples 1-6 and Examples 7-8).

From Tables 2-1 and 2-2, the ash components of the acrylic rubber veils (A) to (M) of the examples and reference examples of the present invention and the crumb-shaped acrylic rubbers (N) to (O) of the comparative examples are phosphorus Water resistance can be improved if the total amount of (P), magnesium (Mg), sodium (Na), calcium (Ca), and sulfur (S) is 80% by weight or more or 90% by weight or more, and the amount of ash can be reduced. it can be seen that there is In addition, when the ash component is these components, the releasability of acrylic rubber is remarkably excellent. From Table 2-2, the ash components of the acrylic rubber veils (A) to (M) of Examples and Reference Examples of the present invention coagulated, washed and dehydrated by the method of the present invention are phosphorus (P) and magnesium (Mg). ), it can be seen that it is 80% or more or 90% or more (Examples 1 to 8, Reference Examples 1 to 5 and Comparative Examples 1 to 2). This is because the ash content in the acrylic rubber veil does not remain as it is in the emulsifier and coagulant used in the production, but during the coagulation reaction, the emulsifier sodium phosphate ester is salt-exchanged with the coagulant magnesium sulfate (MgSO ₄ ), resulting in low-water phosphoric acid. As an ester Mg salt, it is inherent in the hydrous crumb and cannot be sufficiently removed by the washing process, but it can be reduced by dehydrating (squeezing moisture out of the hydrous crumb) in a screw type twin screw extrusion dryer (Examples 1 to 8 ), it can be seen that the water content after dehydration is 20% rather than 30%, and more water is squeezed out of the water-containing crumb to reduce the amount of ash and significantly improve the water resistance of the acrylic rubber veil (Examples 1 to 6 and Comparison of Examples 7-8).

Regarding water resistance, data are omitted in the present examples, but when phosphoric acid ester salt is used as an emulsifier, it can hardly be reduced by the washing process, especially by washing at room temperature, it can be almost reduced no matter how much the number of washings is increased. On the other hand, using a sulfuric acid ester salt such as sodium lauryl sulfate as an emulsifier, it has better water resistance than ash with a lot of sulfur (S) or sodium (Na), and in particular, it has the same degree of The amount of ash was more than 5 times, but the water resistance was excellent. In addition, even when a sulfuric acid ester salt such as sodium lauryl sulfate is used as an emulsifier, the amount of ash can be reduced to 0.1% by weight or less and the water resistance can be remarkably improved by carrying out the coagulation reaction of the present invention, followed by washing with hot water and dehydration. checking that there is

From Table 2-2, the acrylic rubber veils (A) to (H) of the present invention are excellent in state physical properties including Banbury processability, water resistance, compression set resistance, and strength characteristics, and remarkably excellent in injection moldability. It can be seen (Examples 1 to 8).

From Table 2-2, the injection moldability is strongly influenced by the molecular weight distribution (Mw/Mn) of the acrylic rubber, and Comparative Example 2 has Mw/Mn = 1.3/injection moldability: x, Reference Example 5 has Mw/ Mn = 1.55/injection moldability: △, Reference Example 4 has Mw/Mn = 1.99/injection moldability: ○, Examples 3 to 8 and Reference Examples 1 to 3 have Mw/Mn = 2.39 to 2.45/injection moldability: ◎, and Examples 1 to 2 have Mw/Mn = 2.91 to 2.94/injection moldability: As shown in ○, it is most excellent when Mw/Mn is around 2.4, and it can be seen that the acrylic rubber of the present invention has excellent injection moldability. there is. In addition, the molecular weight distribution (Mz/Mw) centering on the high molecular weight region is sufficiently wide, and the number average molecular weight (Mn), weight average molecular weight (Mw), and z average molecular weight (Mz) are sufficiently large, and the Mw/Mw of the present invention is sufficiently large. It can be seen that when the Mn is within the range, the injection moldability can be improved without impairing the strength characteristics (Comparison of Examples 1 to 8, Reference Examples 1 to 5, and Comparative Example 2).

From Tables 2-1 and 2-2, acrylic rubber veils (A) to (M) having a molecular weight distribution (Mw/Mn) in a specific range with excellent injection moldability without deteriorating strength characteristics, generating a specific amount of organic radicals. It turns out that it can be manufactured by using n-dodecyl mercaptan as a chain transfer agent and a chain transfer agent, especially as a chain transfer agent (Examples 1 to 8 and Reference Examples 1 to 5). From Tables 2-1 and 2-2, a chain transfer agent (n-dodecylmercaptan) is added initially rather than continuously added (Reference Example 5). It can be seen that injection moldability can be improved without impairing strength characteristics by post-adding batchwise without deterioration (Examples 1 to 8 and Reference Examples 1 to 4). This is because one polymer chain is lengthened by not adding a chain transfer agent at the beginning and reducing the amount of organic radical generating agent, and by adding a chain transfer agent in the middle of the polymerization, the GPC chart does not show a clear diacid, but the high molecular weight component and the low molecular weight component are balanced. It is presumed that it is manufactured well and the molecular weight distribution (Mw/Mn) can be made within a specific range, and the strength characteristics and injection moldability are highly balanced. In addition, in order to effectively widen the molecular weight distribution (Mw/Mn), the number of batchwise post-additions has a great influence, and the molecular weight distribution (Mw/Mn) is wider when the number of batchwise post-additions is 2 times than 3 times. (Comparison of Reference Examples 1 to 3 and Reference Example 4). In addition, although not shown in Tables 2-1 and 2-2, in the examples of the present application, sodium ascorbate as a reducing agent was added 120 minutes after the start of the polymerization. By doing so, the production of high molecular weight components of acrylic rubber was facilitated, and chain transfer agent The effect of widening the molecular weight distribution (Mw/Mn) of post-addition is increasing.

From Tables 2-1 and 2-2, furthermore, when the drying of the hydrous crumb was changed from direct drying to a screw-type twin-screw extrusion dryer and the operation was performed under normal conditions, the molecular weight distribution (Mw/Mn) did not change (Example 5 Comparison of ~ 8 and Reference Examples 1 ~ 3), the molecular weight distribution (Mw/Mn) of acrylic rubber is broadened by setting the drying conditions of the screw type twin screw extrusion dryer with the optimum shear to further improve the injection moldability of acrylic rubber. However, if the molecular weight distribution (Mw/Mn) is excessively widened (comparison between Examples 3 and 4 and Reference Example 4), it can be seen that the effect of injection moldability is reduced (Examples 1 to 2 and Examples 5 to 8). comparison). In addition, although not shown in Examples and Comparative Examples of the present application, it can be seen that when the redox catalyst of the inorganic radical generator is used, the molecular weight distribution (Mw/Mn) of the obtained acrylic rubber is excessively widened, resulting in poor injection moldability. This is because, in the case of organic radical generators, the polymerization catalyst is inside the micelles of emulsion polymerization and polymerization is continuously performed within the micelles, but in the case of inorganic radical generators, the polymerization catalyst is present outside the micelles and polymerization is carried out outside the micelles. It is thought that the difference in molecular weight distribution occurred and influenced the injection moldability.

From Table 2-2, it can be seen that the acrylic rubber veils (A) to (H) of the present invention are excellent in state physical properties, including Banbury processability, water resistance, compression set resistance, and strength characteristics, and are remarkably excellent in storage stability. can

From Table 2-2, with regard to storage stability, the specific gravity of the acrylic rubber veils (A) to (M) is much larger than that of the crumb-like acrylic rubbers (N) to (O), and the specific gravity is large or small, that is, the amount of air mixed in. It turns out that storage stability is influenced by (comparison with Examples 1-8, Reference Examples 1-5, and Comparative Examples 1-2). The acrylic rubber bale having a high specific gravity is baled by compressing crumb-like acrylic rubber with a baler (Reference Examples 1 to 5), more preferably by extruding into a sheet shape with a screw-type twin-screw extrusion dryer, laminating and baling ( Examples 1 to 8) can be obtained. It is also known that the storage stability of the acrylic rubber veil is more preferable as the amount of ash is smaller (Examples 1 to 8 and Reference Examples 1 to 5). On the other hand, when measuring the characteristic values of the acrylic rubber bale M of Reference Example 5 directly without using a baler and directly drying the crumb-like acrylic rubber as it is, the specific gravity is as small as 0.769, except for Reference Example 5 in Table 2-2. was the same as the result of In addition, it was important for the storage stability of the acrylic rubber veil that the pH was 6 or less.

[About the grain size of the generating function crumb]

For the hydrous crumbs generated in the solidification process in Examples 1 to 8, Reference Examples 1 to 5, and Comparative Examples 1 to 2, (1) 710 μm to 6.7 mm (passing 6.7 mm without passing through 710 μm), (2 ) 710 μm to 4.75 mm (passing 4.75 mm without passing 710 μm), (3) 710 μm to 3.35 mm (passing 3.35 mm without passing 710 μm), using a JIS sieve for the ratio to the total amount of crumbs generated was measured. Their results are shown below.

Example 1: (1) 91 wt%, (2) 91 wt%, (3) 84 wt%

Example 2: (1) 96 wt%, (2) 95 wt%, (3) 89 wt%

Example 3: (1) 91 wt%, (2) 85 wt%, (3) 79 wt%

Example 4: (1) 93 wt%, (2) 90 wt%, (3) 84 wt%

Example 5: (1) 95 wt%, (2) 93 wt%, (3) 90 wt%

Example 6: (1) 89 wt%, (2) 85 wt%, (3) 79 wt%

Example 8: (1) 94 wt%, (2) 93 wt%, (3) 87 wt%

Reference Example 1: (1) 95% by weight, (2) 94% by weight, (3) 91% by weight

Reference Example 2: (1) 89% by weight, (2) 86% by weight, (3) 83% by weight

Reference Example 3: (1) 95% by weight, (2) 94% by weight, (3) 88% by weight

Reference Example 4: (1) 93% by weight, (2) 93% by weight, (3) 90% by weight

Reference Example 5: (1) 93% by weight, (2) 89% by weight, (3) 78% by weight

Comparative Example 1: (1) 17% by weight, (2) 3% by weight, (3) 0% by weight

Comparative Example 2: (1) 10% by weight, (2) 2% by weight, (3) 0% by weight

From these results, even if the size of the hydrous crumb generated in the solidification process is the same, the amount of ash remaining in the acrylic rubber veil is different, and the cleaning efficiency of those with a high specific ratio of (1) to (3) is high, and the amount of ash It can be seen that this is reduced and the water resistance is excellent (comparison of Reference Examples 1 to 5 and Comparative Examples 1 to 2 in Table 2-2). In addition, the ash removal rate at the time of dehydration is also high for the hydrous crumb with a high specific ratio of (1) to (3), and the dehydration rate (moisture content) of 20% by weight (Examples 1 to 6) has a dehydration rate (moisture content) ) 30% by weight (Examples 7 to 8), it can be seen that the amount of ash is reduced and the water resistance of the acrylic rubber veil is improved.

On the other hand, for reference, in the coagulation process, the same procedure as in Comparative Example 1 was performed except that the emulsion polymerization solution was added to the coagulation solution (Reference Example 6), and the emulsion polymerization solution was added to the coagulation solution to increase the coagulant concentration of the coagulation solution. Except for changing from 0.7% by weight to 2% by weight, the procedure was the same as in Comparative Example 1 (Reference Example 7), and the particle size ratio of the resulting hydrous crumb (1) to (3) and the amount of ash in the acrylic rubber veil (4) was measured.

Reference Example 6: (1) 91% by weight, (2) 57% by weight, (3) 25% by weight, (4) 0.51% by weight

Reference Example 7: (1) 92% by weight, (2) 75% by weight, (3) 42% by weight, (4) 0.40% by weight

For the acrylic rubber compositions including the acrylic rubber veils (A) to (H) of Examples 1 to 8, the Mooney scorch time t5 (min. ) was measured according to JIS K 6300, and Mooney Scotch storage stability was evaluated according to the following criteria. As a result, all were good results of "◎".

◎: Mooney scorch time t5 exceeding 3.3 minutes

○: Mooney scorch time t5 is 2 to 3.3 minutes

×: Mooney scorch time t5 is less than 2 minutes

On the other hand, with respect to these acrylic rubber bales (A) to (H), the cooling rate of the sheet-shaped dry rubber extruded from the screw-type twin-screw extrusion dryer is actually as fast as about 200 ° C./hr, similar to Example 1, and all of them It is 40 degrees C/hr or more.

In addition, for each rubber sample, the variance in the amount of methyl ethyl ketone insoluble was evaluated by the method described above. That is, the variance evaluation of the methyl ethyl ketone insoluble content of rubber samples was evaluated based on the above criteria by measuring the methyl ethyl ketone insoluble content of 20 points randomly selected from 20 parts (20 kg) of rubber samples.

As rubber samples, acrylic rubber veils (A) to (H) obtained in Examples 1 to 8 and crumb-like acrylic rubber (O) obtained in Comparative Example 2 were evaluated for variation in gel amount, and acrylic rubber veils (A) The results of ~ (H) were all "◎", and the result of the crumb-like acrylic rubber (O) was "x".

This is because the acrylic rubber bales (A) to (H) are melt-kneaded and dried with a screw-type twin-screw extrusion dryer, so that the amount of gel insoluble in methyl ethyl ketone is almost lost and the variation in gel amount is also almost eliminated, so the Banbury processability is remarkably improved. It is hypothesized that it could be improved.

On the other hand, the crumb-like acrylic rubber subjected to emulsion polymerization and coagulation washing under the conditions for producing the crumb-like acrylic rubber (O) of Comparative Example 2 was put into a screw-type twin-screw extrusion dryer under the same conditions as in Example 1, and extruded and dried. It has been found that the gel amount and gel amount variation measured for the obtained acrylic rubber can be reduced to a level substantially equivalent to that of the acrylic rubber veil (A), and the Banbury workability can be remarkably improved.

[Releasability to mold]

The rubber compositions of the acrylic rubber veils (A) to (H) obtained in Examples 1 to 8 were press-fitted into a 10 mm Φ × 200 mm mold, and the cross-linked rubber product after cross-linking at a mold temperature of 165 ° C. for 2 minutes was taken out, and based on the following criteria When the mold releasability was evaluated, all of the acrylic rubber veils (A) to (H) were evaluated as "◎", which was good.

◎: It can be easily released from the mold, and there is no mold residue.

○: It can be easily released from the mold, but very small mold residues are observed

△: It can be easily released from the mold, but there is a slight mold residue.

×: Difficult to remove from mold

1 Acrylic rubber manufacturing system
3 coagulation device
4 cleaning device
5 screw extruder
6 cooling unit
7 Baling device

Claims (50)

It is made of acrylic rubber having an ionic reactive group, the gel amount of methyl ethyl ketone insoluble content is 15% by weight or less, all values measured at 20 points are within the range of (average value ± 5)% by weight, pH is 6 or less, An acrylic rubber veil having an amount of 0.0005% by weight or more and 0.2% by weight or less, and the total amount of sodium, sulfur, calcium, magnesium, and phosphorus in the ash is 90% by weight or more. According to claim 1,
An acrylic rubber veil wherein the ionic reactive group is at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom. According to claim 1 or 2,
An acrylic rubber veil with a specific gravity of 0.8 or more. According to any one of claims 1 to 3,
An acrylic rubber veil in which the ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of the acrylic rubber is in the range of 1 to 25. According to any one of claims 1 to 4,
An acrylic rubber veil in which the ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of the acrylic rubber is in the range of 1.5 to 3. According to any one of claims 1 to 5,
An acrylic rubber veil in which the number average molecular weight (Mn) of acrylic rubber is in the range of 10,000 to 3,000,000. According to any one of claims 1 to 6,
An acrylic rubber veil in which the number average molecular weight (Mn) of acrylic rubber is in the range of 300,000 to 1.500,000. According to any one of claims 1 to 7,
An acrylic rubber veil wherein the GPC measurement solvent for the weight average molecular weight (Mw) or number average molecular weight (Mn) of acrylic rubber is a dimethylformamide solvent. According to any one of claims 1 to 8,
An acrylic rubber veil in which the gel amount of the methyl ethyl ketone insoluble component is 5% by weight or less. According to any one of claims 1 to 9,
An acrylic rubber having a ratio ([η]100°C/[η]60°C) of the complex viscosity at 100°C ([η]100°C) and the complex viscosity at 60°C ([η]60°C) of 0.7 or more. veil. According to any one of claims 1 to 10,
An acrylic rubber veil having a water content of less than 1% by weight. According to any one of claims 1 to 11,
An acrylic rubber veil obtained by emulsion polymerization using a phosphoric acid ester salt or a sulfuric acid ester salt as an emulsifier. According to any one of claims 1 to 12,
An acrylic rubber veil obtained by coagulating an emulsion polymerized polymerization solution by using an alkali metal salt or a metal salt of Group 2 of the periodic table as a coagulant and drying it. According to any one of claims 1 to 13,
An acrylic rubber veil that is melt-kneaded and dried after solidification. According to claim 14,
An acrylic rubber veil in which the above melt kneading and drying are performed in a state in which water is not substantially contained. The method of claim 14 or 15,
An acrylic rubber veil in which the above melt kneading and drying are performed under reduced pressure. According to any one of claims 14 to 16,
After the above melt kneading and drying, an acrylic rubber veil cooled at a cooling rate of 40 ° C./hr or more. According to any one of claims 1 to 17,
An acrylic rubber veil obtained by washing, dehydrating, and drying hydrous crumbs having a particle size of 710 μm to 6.7 mm in a ratio of 50% by weight or more. A monomer component composed of at least one (meth)acrylic acid ester selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters, an ionic reactive group-containing monomer, and optionally other monomers is mixed with water An emulsification step of emulsifying with an emulsifier;
An emulsion polymerization step of obtaining an emulsion polymerization solution by emulsion polymerization in the presence of a redox catalyst composed of a radical generator and a reducing agent;
A coagulation step of bringing the obtained emulsion polymerization liquid into contact with a coagulant to produce a hydrous crumb;
A cleaning step of cleaning the generated hydrous crumb;
The washed hydrous crumb is dehydrated to a moisture content of 1 to 40% by weight in a dewatering barrel using a screw-type twin-screw extrusion dryer having a dewatering barrel with a dehydration slit, a drying barrel under reduced pressure, and a die at the tip, and then to a drying barrel. A dehydration, drying, and molding step of drying to less than the weight percent and extruding a sheet-like dried rubber from a die;
A cooling step of cooling the extruded sheet-like dry rubber;
A cutting step of cutting the cooled sheet-like dry rubber;
Lamination step of laminating cut sheet-shaped dry rubber
Method for producing an acrylic rubber veil comprising a. According to claim 19,
A method for producing an acrylic rubber veil according to any one of claims 1 to 18. The method of claim 19 or 20,
A method for producing an acrylic rubber veil in which, in an emulsion polymerization step, a chain transfer agent is batchwise post-added during emulsion polymerization to continue polymerization. According to any one of claims 19 to 21,
A method for producing an acrylic rubber veil, wherein the contact between the emulsion polymerization liquid and the coagulant in the coagulation step is adding the emulsion polymerization liquid to the stirring coagulation liquid. The method of any one of claims 19 to 22,
In the emulsion polymerization step, a method for producing an acrylic rubber veil in which emulsion polymerization is performed using a phosphoric acid ester salt or a sulfuric acid ester salt as an emulsifier. The method of any one of claims 19 to 23,
A method for producing an acrylic rubber veil in which a polymerization solution produced in an emulsion polymerization step is contacted with a coagulant containing an alkali metal salt or a metal salt of Group 2 of the periodic table to solidify it. The method of any one of claims 19 to 24,
A method for producing an acrylic rubber veil in which a polymerization solution produced in an emulsion polymerization step is brought into contact with a coagulant to solidify, and then melt-kneaded and dried. According to claim 25,
A method for producing an acrylic rubber veil in which the above melt kneading and drying are performed in a state in which water is not substantially contained. The method of claim 25 or 26,
A method for producing an acrylic rubber veil in which the melt kneading and drying are performed under reduced pressure. The method of any one of claims 19 to 27,
A method for producing an acrylic rubber veil wherein the maximum torque of the screw-type twin screw extrusion dryer during melt kneading and drying is in the range of 5 to 125 N m. The method of any one of claims 19 to 28,
A method for producing an acrylic rubber veil in which acrylic rubber after melt kneading and drying is cooled at a cooling rate of 40°C/hr or higher. According to any one of claims 19 to 29,
A method for producing an acrylic rubber veil in which a ratio of 50% by weight or more of hydrous crumb in a particle size range of 710 μm to 6.7 mm is washed, dehydrated, and dried. The method of any one of claims 19 to 30,
A method for producing an acrylic rubber veil, wherein the cutting temperature of the sheet-shaped dry rubber in the cutting step is 60°C or lower. The method of any one of claims 19 to 31,
A method for producing an acrylic rubber veil, wherein the lamination temperature of the sheet-shaped dry rubber in the cooling step is 30°C or higher. A rubber composition comprising a rubber component comprising the acrylic rubber veil according to any one of claims 1 to 18, a filler, and a crosslinking agent. 34. The method of claim 33,
A rubber composition wherein the filler is a reinforcing filler. 34. The method of claim 33,
A rubber composition wherein the filler is carbon black. 34. The method of claim 33,
A rubber composition in which the filler is silica. The method of any one of claims 33 to 36,
A rubber composition wherein the crosslinking agent is an organic crosslinking agent. The method of any one of claims 33 to 37,
A rubber composition in which the crosslinking agent is a polyvalent compound. The method of any one of claims 33 to 38,
A rubber composition in which the crosslinking agent is an ionic crosslinkable compound. The method of claim 39,
A rubber composition in which the crosslinking agent is an ionic crosslinkable organic compound. The method of claim 39 or 40,
A rubber composition in which the crosslinking agent is a polyvalent ion organic compound. The method of any one of claims 39 to 41,
An ion of the ionic crosslinkable compound, ion crosslinkable organic compound, or polyvalent ionic organic compound as the crosslinking agent is at least one ion-reactive group selected from the group consisting of an amino group, an epoxy group, a carboxyl group, and a thiol group. The method of claim 41 ,
The rubber composition in which the crosslinking agent is at least one type of polyvalent ionic compound selected from the group consisting of polyvalent amine compounds, polyvalent epoxy compounds, polyvalent carboxylic acid compounds, and polyvalent thiol compounds. The method of any one of claims 33 to 43,
The rubber composition in which the content of the crosslinking agent is in the range of 0.001 to 20 parts by weight based on 100 parts by weight of the rubber component. The method of any one of claims 33 to 44,
A rubber composition further comprising an anti-aging agent. The method of claim 45,
A rubber composition wherein the anti-aging agent is an amine-based anti-aging agent. A method for producing a rubber composition in which a crosslinking agent is mixed after mixing a rubber component comprising the acrylic rubber veil according to any one of claims 1 to 18, a filler, and, if necessary, an antiaging agent. A crosslinked rubber product formed by crosslinking the rubber composition according to any one of claims 33 to 46. The method of claim 48,
A crosslinked rubber product in which crosslinking of the rubber composition is performed after molding. The method of claim 48 or 49,
A crosslinked rubber product in which the crosslinking of the rubber composition is performed by primary crosslinking and secondary crosslinking.

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