KR20230020397A - Acrylic rubber veil with excellent storage stability and Banbury processability - Google Patents

Abstract

Provided is an acrylic rubber veil excellent in storage stability and Banbury processability. The acrylic rubber veil according to the present invention has at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom, has a specific gravity of 0.9 or more, an ash content of 0.15% by weight or less, and a gel content of 30% by weight or less. In addition, the value obtained by arbitrarily sampling the amount of gel at a plurality of points and measuring the variation is within the range of (average value ± 5)% by weight, and all of the above-mentioned samplings are included.

Description

Acrylic rubber veil with excellent storage stability and Banbury processability

The present invention relates to an acrylic rubber veil, a method for producing the same, a rubber mixture, and a crosslinked rubber, and more particularly, has excellent storage stability and Banbury processability, and also has excellent crosslinkability, water resistance, strength characteristics and resistance to compression set. It relates to an acrylic rubber veil having excellent properties, a method for producing the same, a rubber mixture including 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 (Pamphlet of International Publication No. 2019/188709), monomer components composed of ethyl acrylate, butyl acrylate, methoxyethyl acrylate and monobutyl fumarate, water and sodium lauryl sulfate are charged, degassed under reduced pressure and After repeating nitrogen substitution, sodium aldehyde sulfoxylate and cumene hydroperoxide, an organic radical generator, are added to initiate emulsion polymerization under normal pressure and room temperature, and emulsion polymerization is performed until the polymerization conversion rate reaches 95% by weight, followed by calcium chloride Disclosed is a method of producing acrylic rubber by coagulating an aqueous solution, filtering it with a wire mesh, and then dehydrating and drying it with an extrusion dryer having a screw. However, the acrylic rubber obtained by this method has problems in that roll processability and Banbury processability are extremely poor, and storage stability and water resistance are also poor. Further, Patent Literature 1 does not describe baling the obtained acrylic rubber.

In Patent Document 2 (Japanese Unexamined Patent Publication No. 1-135811), a monomer component composed of ethyl acrylate, caprolactone addition type acrylic acid ester, cyanoethyl acrylate and vinyl chloroacetate and n-dodecylmercaptan as a chain transfer agent is disclosed. 1/4 of the monomer mixture was emulsified with sodium lauryl sulfate, polyethylene glycol nonylphenyl ether and distilled water, sodium sulfite and ammonium persulfate as an inorganic radical generating agent were added to initiate polymerization, and the remaining temperature was maintained at 60°C. A negative monomer mixture and a 2% aqueous solution of ammonium persulfate were added dropwise for 2 hours, and the latex having a polymerization conversion rate of 96 to 99%, after which polymerization was continued for another 2 hours after dropping, was added to an aqueous solution of sodium chloride at 80 ° C. A method of preparing acrylic rubber and crosslinking it with sulfur is disclosed. However, the acrylic rubber obtained by this method has problems such as insufficient roll processability and Banbury processability, and poor storage stability, strength characteristics and water resistance of the crosslinked product.

In Patent Document 3 (Japanese Unexamined Patent Publication No. 2018-168343), monomer components consisting of ethyl acrylate, butyl acrylate and monobutyl fumarate, pure water, sodium lauryl sulfate, polyethylene glycol monostearate, and n-dodecylmercaptan as a chain transfer agent A monomer emulsion consisting of is prepared, and then, 1 part of the monomer emulsion and pure water are put into a polymerization reaction tank, cooled to 12 ° C., and the remainder of the monomer emulsion, ferrous sulfate, sodium ascorbate, and as an inorganic radical generator Potassium sulfate was continuously added dropwise over 2.5 hours, then maintained at 23°C to continue the reaction for 1 hour, then industrial water was added to raise the temperature to 85°C, followed by continuous addition of sodium sulfate at 85°C to solidify the water A method of obtaining crumb, washing with pure water three times and then drying with a hot air dryer to prepare acrylic rubber and crosslinking with 2,2-bis[4-(4-aminophenoxy)phenyl]propane is disclosed. However, although the acrylic rubber obtained by this method has excellent stress relaxation properties and extrusion processability, it has problems such as insufficient roll processability, Banbury processability, and storage stability, and poor strength characteristics and water resistance of the crosslinked product.

In Patent Document 4 (Japanese Unexamined Patent Publication No. 9-143229), a monomer mixture consisting of ethyl acrylate, special acrylate and monochlorovinyl acetate, sodium lauryl sulfate as an emulsifier, n-octyl mercaptan and water as a chain transfer agent are After adding to the reaction vessel, replacing with nitrogen, adding ammonium hydrogen sulfite and sodium persulfate as an inorganic radical generating agent to initiate polymerization, and copolymerizing at 55 ° C. for 3 hours at a reaction conversion rate of 93 to 96% to prepare acrylic rubber A method of crosslinking with sulfur is disclosed. However, the acrylic rubber obtained by this method has problems such as insufficient Banbury processability and poor strength characteristics and water resistance of the crosslinked product.

Patent Document 5 (Japanese Unexamined Patent Publication No. 62-64809) discloses 50 to 99.9% by weight of at least one compound of acrylic acid alkyl esters and acrylic acid alkoxyalkyl esters, dihydrodicyclopentane of an unsaturated carboxylic acid having a radical reactive group. A copolymer having a monomer composition comprising 0.1 to 20% by weight of a vinyl group-containing ester and 0 to 20% by weight of at least one of other monovinyl, monovinylidene, and monovinylene unsaturated compounds, wherein tetrahydrofuran is used as a developing solvent Characterized in that the number average molecular weight (Mn) in terms of one polystyrene is 200,000 to 1.2 million, and the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 10 or less, characterized by processability and compression set Disclosed is an acrylic rubber having excellent tensile strength and capable of sulfur vulcanization. In addition, the number average molecular weight (Mn) is 200,000 to 1,000,000, preferably 200,000 to 1,000,000, and when Mn is less than 200,000, the physical properties and processability of the vulcanized product are deteriorated, and when it exceeds 1.2 million, processability is deteriorated, and weight Regarding the ratio (Mw/Mn) of the average molecular weight (Mw) to the number average molecular weight (Mn), it has been described that when the ratio exceeds 10, the compression set becomes large, which is not preferable. Specific examples thereof include monomer components including ethyl acrylate or radical crosslinkable dihydrodicyclopentenyl acrylate, sodium lauryl sulfate as an emulsifier, potassium persulfate as an inorganic radical generating agent, and thioglycolic acid as a molecular weight regulator. Octyl or t-dodecylmercaptan was added in varying amounts, and the number average molecular weight (Mn) was 53 to 1.15 million, the weight average molecular weight (Mw) was 3.54 to 6.26 million, and the weight average molecular weight (Mw) and number average molecular weight (Mn ) A production method is disclosed in which acrylic rubber having a ratio (Mw/Mn) of 4.7 to 8 is polymerized, solidified in an aqueous calcium chloride solution, washed sufficiently with water, and dried directly. And, when the amount of chain transfer agent is small, the number average molecular weight (Mw) of the obtained acrylic rubber is high at 5,000,000, and the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) narrows to 1.4, When the amount of chain transfer agent is large, the number average molecular weight (Mn) is as small as 200,000, and the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is extremely widened to 17, as shown in Examples and Comparative Examples. it's gone However, since the acrylic rubber obtained by this method is inferior in compression set resistance and storage stability, and also contains a radical reactive group, even if an appropriate molecular weight distribution (Mw/Mn) is obtained in a polymerization reaction using a radical generator, the molecular weight ( Mw and Mn) were large and too complicated, and there was also a problem that Banbury workability and roll workability were not sufficient. In addition, in the crosslinking reaction, the acrylic rubber obtained by the present method is added with sulfur and a vulcanization accelerator as a crosslinking agent and kneaded with a roll, followed by 100 kg/cm ² vulcanization press at 170°C for 15 minutes, and a gear oven at 175°C for 4 hours. As a result, long-term crosslinking is required, and the obtained crosslinked product also has poor compression set resistance, water resistance and strength characteristics, and also has poor change in physical properties after deterioration by heat.

On the other hand, regarding veiled acrylic rubber, for example, in Patent Document 6 (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, acrylic rubber 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 7 (Pamphlet of International Publication No. 2018/116828), ethyl acrylate, n-butyl acrylate, and fumarate mono An acrylic rubber obtained by emulsifying a monomer component composed of n-butyl with sodium lauryl sulfate, polyethylene glycol monostearate, and water as emulsifiers, adding cumene hydroperoxide as an organic radical generating agent, and emulsion polymerization until the polymerization conversion rate reaches 95%. 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 with water once and then washed with a 100-mesh wire mesh. A method for recovering crumb-like acrylic rubber by allowing the entire amount to pass through and capturing only the solid content is disclosed. 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 was a problem that the roll workability or banbury workability of the bale was poor, and even if the bale was produced, the air could not be sufficiently removed, and the storage stability was also poor.

Regarding the gel amount of acrylic rubber, for example, Patent Document 8 (Japanese Patent No. 3599962) contains two or more radical reactive unsaturated groups having different reactivity from 95 to 99.9% by weight of alkyl acrylate or alkoxyalkyl acrylate. 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 0.1 to 5% by weight in the presence of 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, water and sodium lauryl sulfate, polyoxyethylene nonylphenyl ether, sodium carbonate and boric acid were added as emulsifiers, and the temperature was adjusted to 75° C., and then t-butyl hydroperoxide, longite, and ethylenediaminetetraacetic acid as organic radical generators were added. Disodium and ferrous sulfate are added (pH at this time is 7.1), and then the monomer components of ethyl acrylate and allyl methacrylate are added dropwise to perform emulsion polymerization. The obtained emulsion (pH 7) is mixed with sodium sulfate aqueous solution. It is salted out, 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 region, and even if processability is improved, storage stability and strength characteristics are poor, and roll processability, Banbury processability, crosslinkability and resistance are poor. There was also a problem of poor compression set characteristics.

Further, in Patent Document 9 (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 this technology, 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 a method for improving workability such as roll workability or Banbury.

International Publication No. 2019/188709 Pamphlet Japanese Unexamined Patent Publication No. 1-135811 Japanese Unexamined Patent Publication No. 2018-168343 Japanese Unexamined Patent Publication No. 9-143229 Japanese Unexamined Patent Publication No. 62-64809 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 has been made in view of the actual situation of the prior art, and is excellent in storage stability and Banbury processability, and also has excellent crosslinkability in a short time, water resistance, strength characteristics, and compression set resistance characteristics, and a method for producing the same , It is an object to provide a rubber mixture containing the acrylic rubber veil and a rubber crosslinked product formed by crosslinking it.

As a result of intensive research in view of the above problems, the inventors of the present invention have found that the acrylic rubber veil contains at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, and the specific gravity, ash content, and gel amount are within specific ranges. It was found that the storage stability and Banbury processability were excellent, and the short-time crosslinkability, water resistance, strength characteristics, and compression set resistance were highly excellent by controlling the variation in the amount of gel in the acrylic rubber veil.

The inventors of the present invention, when the gel amount is the amount of insoluble content of a specific solvent, particularly correlates with BIT (Black Incorporation Time) during Banbury processing, and when the gel amount of the specific solvent insoluble content in an acrylic rubber veil is disturbed, Banbury processability It was found that the processability of Banbury can be significantly improved by controlling the variation in the amount of gel in the acrylic rubber veil.

The present inventors also found that the gel amount of the specific solvent-insoluble component of the acrylic rubber veil is generated during the polymerization of the acrylic rubber, and in particular, increases rapidly when the polymerization conversion is increased to improve the strength characteristics, thereby deteriorating the Banbury workability of the acrylic rubber veil to control Although it is difficult to do this, after cleaning, the hydrous crumb produced in the coagulation process is melt-kneaded in a screw-type twin-screw extrusion dryer in a substantially water-free state (moisture content less than 1% by weight), followed by extrusion drying, so that the specific solvent-insoluble content rapidly increases. As a result, the gel amount and gel amount variation of the specific solvent-insoluble component in the acrylic rubber veil to be produced can be reduced, and the Banbury processability can be remarkably improved without impairing the strength characteristics of the acrylic rubber veil. Found out.

The present inventors also found that, by setting the specific gravity within a specific range, the storage stability can be remarkably improved while maintaining the properties such as Banbury processability, crosslinkability, water resistance, strength characteristics, and compression set resistance of the acrylic rubber veil. Found out. The acrylic rubber of the present invention having a specific reactive group such as a carboxyl group is sticky and difficult to remove once air is mixed in, and in the crumb-like acrylic rubber where the hydrous crumb is directly dried, a large amount of air is mixed (the specific gravity decreases). Storage stability was deteriorating. The inventors of the present invention, by compressing the crumb-like acrylic rubber with a high-pressure baler or the like to bale, can remove some air and improve the storage stability of the acrylic rubber bale, preferably, the water-containing crumb into a screw type 2 It was found that by extruding and drying under reduced pressure with a screw extrusion dryer to extrude and laminate into an air-free sheet form, an acrylic rubber veil containing almost no air (high specific gravity) and having significantly improved storage stability can be produced. paid The present inventors have further found that the specific gravity with the air content taken into account can be measured according to JIS K6268 Crosslinked Rubber-Method A of Density Measurement using the difference in buoyancy.

The present inventors also found that storage stability, Banbury workability, short-time crosslinkability, strength characteristics, and compression set resistance were excellent as well as water resistance was excellent by setting the amount of ash in the acrylic rubber veil or the amount of components in the ash within a specific range. The present inventors have found that the present acrylic rubber production relies on an emulsion polymerization method that uses a large amount of an emulsifier and a coagulant, and it is difficult to reduce the amount of ash in the acrylic rubber veil. It was found that the washing efficiency with this hot water and the ash removal efficiency during dehydration were remarkably excellent, and the water resistance of the acrylic rubber veil could be remarkably improved. The present inventors also found that when a specific emulsifier is used in the emulsion polymerization of acrylic rubber, or when a specific coagulant is used in the case of coagulating the emulsion polymerization solution, the water resistance of the acrylic rubber veil is excellent and the mold release property is remarkably increased. found out what

The present inventors have also found that an acrylic rubber veil having a reactive group that reacts with a crosslinking agent such as a carboxyl group, an epoxy group or a chlorine atom, etc., is highly excellent in short-time crosslinkability, strength characteristics and compression set resistance.

In addition, in the GPC measurement of an acrylic rubber having a reactive group of either a carboxyl group, an epoxy group or a chlorine atom, the inventors of the present invention copolymerized ethyl acrylate and dihydrodicyclopentenyl acrylate of the prior art, and the like. It was not sufficiently soluble in tetrahydrofuran used for GPC measurement of rubber, and it was not possible to measure each molecular weight or molecular weight distribution clearly and reproducibly. It was found that it can be dissolved and measured reproducibly, and furthermore, by specifying the respective characteristic values, the Banbury workability, crosslinkability, strength characteristics and compression set resistance characteristics of the acrylic rubber veil can be highly balanced.

The present inventors further set the number average molecular weight (Mn) and weight average molecular weight (Mw) of the absolute molecular weight measured by the GPC-MALS method within a specific range, and furthermore, the weight average molecular weight (Mw) and number of absolute molecular weight distributions It has been found that by slightly widening the ratio of average molecular weight (Mn) (Mw/Mn), it is possible to highly balance the processability of acrylic rubber veil rolls and Banbury and the strength characteristics of the crosslinked product. In order to improve the roll processability of the acrylic rubber veil, the inventors of the present invention, in particular, specify the number average molecular weight (Mn) or weight average molecular weight (Mw) of the acrylic rubber in the constituent components, so that the weight average molecular weight (Mw) and number average It is important to widen the ratio (Mw/Mn) of the molecular weight (Mn), and it was not easy to manufacture, but the chain transfer agent in the polymerization reaction is added batchwise or in a screw type twin screw extrusion dryer. It was found that it can be manufactured by melt-kneading and drying with a high shear.

The present inventors further improved Mooney scorch stability without compromising properties such as storage stability, roll processability, Banbury processability, water resistance, strength characteristics, and compression set resistance of acrylic rubber veils by increasing the cooling rate after drying. I figured out what I could do.

The inventors of the present invention also emulsify specific monomer components with water and an emulsifier, initiate emulsion polymerization in the presence of a redox catalyst composed of an inorganic radical generator such as potassium persulfate and a reducing agent, and then perform emulsion polymerization, by a specific method The hydrous crumb produced by coagulation is washed with hot water, then dehydrated to a specific water content using a specific screw-type extrusion dryer, and melt-kneaded and dried to a state that substantially does not contain water, thereby reducing the amount of ash and gel, In addition, it was found that the dispersion of the gel amount was eliminated, and an acrylic rubber veil was obtained that was remarkably excellent in storage stability, Banbury processability, crosslinkability, water resistance, strength characteristics, and compression set resistance.

The present inventors also carried out emulsion polymerization by batchwise adding a chain transfer agent during emulsion polymerization, thereby increasing the ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of the acrylic rubber to be polymerized. In addition, it was found that the gel amount of the methyl ethyl ketone insoluble component could be reduced, and the roll processability and Banbury processability of the resulting acrylic rubber veil could be remarkably improved.

The present inventors have further found that an acrylic rubber veil excellent in roll processability and Banbury processability can be manufactured by further melt-kneading and drying acrylic rubber under conditions of high shear using a specific extrusion dryer.

The present inventors also found that, in the rubber mixture comprising the acrylic rubber veil, filler and crosslinking agent of the present invention, by blending carbon black or silica as a filler, roll processability, Banbury processability and crosslinkability in a short time are excellent, and It was found that the cross-linked product had highly excellent water resistance, strength characteristics, and resistance to compression set. The inventors also found that, as the crosslinking agent, an organic compound, a polyvalent compound, or an ionic crosslinking compound is preferred, for example, an ionic reactive group reacting with an ionic reactive group of an acrylic rubber veil such as an amine group, an epoxy group, a carboxyl group or a thiol group. It was found that, by being a polyvalent ionic organic compound having a plurality of groups, roll processability, Banbury processability, and crosslinkability in a short time are excellent, and the crosslinked product has highly excellent water resistance, strength characteristics, and resistance to compression set.

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

Thus, according to the present invention, it has at least one reactive group selected from the group consisting of carboxyl group, epoxy group and chlorine atom, specific gravity is 0.9 or more, ash content is 0.15% by weight or less, gel amount is 30% by weight or less, and An acrylic rubber veil is provided in which the value when the gel amount is arbitrarily sampled at a plurality of points and the deviation is measured, and all of the above-mentioned samplings measured within the range of (average value ± 5) weight%.

In the acrylic rubber veil of the present invention, the multi-point sampling is preferably 20-point sampling.

In the acrylic rubber veil of the present invention, it is preferable that the gel amount is a methyl ethyl ketone insoluble component.

In the acrylic rubber veil of the present invention, the reactive group is preferably an ion reactive group.

In the acrylic rubber veil of the present invention, it is preferable that the weight average molecular weight (Mw) of the absolute molecular weight measured by the GPC-MALS method is in the range of 1 million to 3.5 million.

In the acrylic rubber veil of the present invention, it is preferable that the number average molecular weight (Mn) of the absolute molecular weight measured by the GPC-MALS method is in the range of 100,000 to 500,000.

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 absolute molecular weight distribution measured by the GPC-MALS method is preferably 3.5 or more.

In the acrylic rubber veil of the present invention, the measurement solvent of the GPC-MALS method is preferably a dimethylformamide solvent.

In the acrylic rubber veil of the present invention, the total amount of sodium, magnesium, calcium, phosphorus and sulfur in the ash is preferably 60% by weight or more.

In the acrylic rubber veil of the present invention, it is preferable that the specific gravity is 0.95 or more.

In the acrylic rubber veil of the present invention, the pH is preferably 6 or less.

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

In the acrylic rubber veil of the present invention, it is preferable that the polymerization solution subjected to emulsion polymerization is coagulated 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, wherein the melt-kneaded and dried are performed in a state that does not substantially contain water, the melt-kneaded and It is preferable that drying is performed under reduced pressure. Further, 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.

According to the present invention, further, a step of emulsifying an acrylic rubber monomer component containing a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom with water and an emulsifier;

An emulsion polymerization step of obtaining an emulsion polymerization solution by initiating a polymerization reaction and performing an emulsion polymerization reaction in the presence of a redox catalyst containing an inorganic radical generator and a reducing agent;

A coagulation step of adding the obtained emulsion polymerization liquid to a coagulating liquid stirred at a circumferential speed of 1 m/s or more and coagulating it to generate a hydrous crumb;

A cleaning step of washing the generated hydrous crumb with hot water;

A step of dewatering the washed hydrous crumb to a moisture content of 1 to 40% by weight in a dehydration barrel using a dehydration barrel having a dehydration slit, a drying barrel under reduced pressure, and a screw-type twin-screw extrusion dryer having a die at the tip;

A drying step of drying to less than 1% by weight in a drying barrel;

A molding step of extruding the sheet-shaped dry rubber from a die;

Lamination process in which extruded sheet-like dry rubber is laminated after cutting

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 production method of the acrylic rubber veil of the present invention, it is preferable that the chain transfer agent is post-added batchwise during polymerization in the emulsion polymerization step.

In the production method of the acrylic rubber veil of the present invention, the maximum torque of the screw-type twin-screw extrusion dryer is preferably 25 N·m or more.

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.

In the production method of the acrylic rubber veil of the present invention, it is preferable to coagulate the polymerization solution produced in the emulsion polymerization step by using an alkali metal salt or a periodic table Group 2 metal salt as a coagulant and then dry it.

In the method for producing an acrylic rubber veil of the present invention, it is preferable to add the polymerization liquid produced in the emulsion polymerization step to an aqueous solution containing a coagulant containing an alkali metal salt or a metal salt of Group 2 of the periodic table, and coagulate it by stirring.

In the production method of the acrylic rubber veil of the present invention, it is preferable to solidify the polymerization solution produced in the emulsion polymerization step by contacting it with a coagulant, followed by melt kneading and drying.

In the production method of the acrylic rubber veil of the present invention, it is preferable that the melt kneading and drying are carried out in a state that does not substantially contain moisture.

In the production method of 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 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.

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

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

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

In the rubber mixture of the present invention, the ion of the ion crosslinkable compound, ion crosslinkable organic compound or multivalent ion organic compound as the crosslinking agent is at least one ionic reactive group selected from the group consisting of an amino group, an epoxy group, a carboxyl group and a thiol group. it is desirable

In the rubber mixture 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 mixture 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.

In the rubber mixture of the present invention, it is preferable to further contain an anti-aging agent. Further, in the rubber mixture 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 mixture in which a crosslinking agent is mixed after mixing a rubber component including the acrylic rubber veil, a filler, and, if necessary, an antiaging agent.

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

According to the present invention, an acrylic rubber veil having highly excellent storage stability, Banbury processability, short-time crosslinking property, water resistance, strength and compression set resistance, an efficient manufacturing method thereof, a high-quality rubber mixture including the acrylic rubber veil, and A crosslinked rubber product obtained by crosslinking it is 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 at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, has a specific gravity of 0.9 or more, an ash content of 0.15% by weight or less, and a gel content of 30% by weight or less. It is characterized in that the value when the gel amount is arbitrarily sampled at a plurality of points and the deviation is measured, all of the above-mentioned samplings measured within the range of (average value ± 5) weight%.

<reactive group>

The acrylic rubber veil of the present invention is characterized by having at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom.

The at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom is not particularly limited, but is preferably an ionic reactive group involved in an ionic reaction, more preferably an epoxy group, a carboxyl group, and particularly preferably a carboxyl group. It is suitable because it can highly improve the crosslinkability in a short time and the compression set resistance or water resistance of the crosslinked product.

The content of 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 is not particularly limited, and may be appropriately selected depending on the purpose of use. In the weight ratio of the reactive group itself, Usually 0.001 to 5% by weight, preferably 0.01 to 3% by weight, more preferably 0.05 to 1% by weight, particularly preferably 0.1 to 0.5% by weight, when it is in the range of workability or crosslinkability, and crosslinked products It is suitable because the properties such as strength characteristics, compression set resistance, oil resistance, cold resistance, and water resistance are highly balanced.

The acrylic rubber veil having at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom of the present invention introduces at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom in a post-reaction to acrylic rubber. However, an acrylic rubber obtained by copolymerizing a monomer containing the reactive group is preferable.

<Monomer component>

The monomer component of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited as long as it is a monomer constituting a normal acrylic rubber having at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom, but preferably is an acrylic rubber monomer component containing a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom, more preferably a group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters. It consists of at least one (meth)acrylic acid ester selected from, a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, and other monomers copolymerizable as necessary. 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, a (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)acrylate. 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 the (meth)acrylic acid alkoxyalkyl ester 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. 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 monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom is not particularly limited and is appropriately selected depending on the purpose of use, preferably an ion-reactive reactive group, more preferably a carboxyl group and / or a monomer having an epoxy group, more preferably a monomer having a carboxyl group, is suitable because it can highly improve the crosslinkability in a short time and the resistance to compression set and water resistance of the crosslinked product.

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 an acrylic rubber sheet is made of a cross-linked rubber.

The ethylenically unsaturated monocarboxylic acid is not particularly limited, but ethylenically unsaturated monocarboxylic acids having 3 to 12 carbon atoms are 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, and 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, and more preferably C2-C6 alkyl monoesters of C4 butenedioic acid.

Specific examples of ethylenically unsaturated dicarboxylic acid monoesters 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, (meth)acrylic acid chloroacyloxyalkyl 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-(chloroacetic acid). Toxy)propyl, (meth)acrylic acid 3-(hydroxychloroacetoxy)propyl, etc. are mentioned. Examples of the (meth)acrylic acid (chloroacetylcarbamoyloxy)alkyl ester include 2-(chloroacetylcarbamoyloxy)ethyl (meth)acrylic acid and 3-(chloroacetylcarbamoyloxy)ethyl (meth)acrylic acid. ) 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 aromatic vinyl compound having a chloromethyl group 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 and p-vinylbenzylchloroacetic acid ester.

The monomers containing at least one reactive group selected from the group consisting of carboxyl groups, epoxy groups, and chlorine atoms are used alone or in combination of two or more, and the ratio in all monomer components is usually 0.01 to 10% by weight, preferably 0.01 to 10% by weight. is in the range of 0.05 to 8% by weight, more preferably 0.1 to 6% by weight, particularly preferably 0.5 to 5% by weight, most preferably 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 types, 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 has at least one reactive group selected from the group consisting of the aforementioned carboxyl group, epoxy group, and chlorine atom, and preferably has the aforementioned alkyl (meth)acrylate ester and alkoxyalkyl (meth)acrylate. At least one (meth)acrylic acid ester selected from the group consisting of esters, a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, and a bonding unit from other monomers included as necessary. , and each ratio in the acrylic rubber is such that the bonding unit derived from at least one (meth)acrylic acid ester selected from the group consisting of (meth)acrylic acid alkyl esters and (meth)acrylic acid alkoxyalkyl esters is usually 50 to 50 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 87 to 99% by weight, and carboxyl groups, epoxy groups and The bonding unit derived from a monomer containing at least one reactive group selected from the group consisting of chlorine atoms 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 It is preferably 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 an absolute molecular weight measured by the GPC-MALS method, usually 100,000 to 500,000 (100,000 to 500,000), preferably Preferably in the range of 200,000 to 480,000, more preferably 250,000 to 450,000, particularly preferably 300,000 to 400,000, and most preferably 350,000 to 400,000, the roll workability, strength characteristics and compression set resistance of the acrylic rubber veil are highly balanced and fit

The weight average molecular weight (Mw) 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 an absolute molecular weight measured by the GPC-MALS method, and is usually 1,000,000 to 3,500,000 (100 10,000 to 3,500,000), preferably 1,200,000 to 3,000,000, more preferably 1,300,000 to 3,000,000, particularly preferably 1,500,000 to 2,500,000, most preferably 1,900,000 to 2,100,000 Roll workability and strength properties of the acrylic rubber veil, and compression set resistance 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 an absolute molecular weight with emphasis on the high molecular weight region measured by the GPC-MALS method, Usually 1,500,000 to 6,000,000 (1.5 million to 6 million), preferably 2,000,000 to 5,000,000, more preferably 2,500,000 to 4,500,000, particularly preferably 3,000,000 to 4,000,000 Roll workability, Banbury workability, and strength properties of the acrylic rubber veil , and compression set resistance 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 (Mw/Mn) is not particularly limited, but the absolute molecular weight distribution measured by the GPC-MALS method , is usually 3.5 or more, preferably 3.6 or more, more preferably 3.7 or more, still more preferably 4 or more, particularly preferably 4.5 or more, and most preferably 4.7 or more. If 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 is excessively small, the Banbury processability of the acrylic rubber veil is deteriorated, 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 is usually 3.7 to 6.5, preferably 3.8 to 6.2, more preferably When the range is preferably 4 to 6, particularly preferably 4.5 to 5.7, and most preferably 4.7 to 5.5, the roll processability of the acrylic rubber veil, strength characteristics when crosslinked, and compression set resistance are highly balanced and suitable. .

The ratio (Mz/Mw) of the z-average molecular weight (Mz) to the weight-average molecular weight (Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is not particularly limited and is appropriately selected depending on the purpose of use. GPC-MALS method Absolute molecular weight distribution with emphasis on the polymer region measured by , usually 1.3 or more, preferably 1.5 or more, more preferably 1.6 or more, still more preferably 1.7 or more, and most preferably 1.8 or more. If the ratio (Mz/Mw) of the z-average molecular weight (Mz) to the weight-average molecular weight (Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is excessively small, roll processability or Banbury processability is poor, which is not preferable. In addition, the ratio (Mz/Mw) of the z-average molecular weight (Mz) to the weight-average molecular weight (Mw) of the acrylic rubber constituting the acrylic rubber veil of the present invention is usually in the range of 1.8 to 2.4, more preferably 1.8 to 2. It is suitable because it can highly improve roll workability or Banbury workability without damaging the strength characteristics of the acrylic rubber veil.

Here, the "GPC-MALS method" is the following content. GPC (gel permeation chromatography) is a type of liquid chromatography that separates based on differences in molecular sizes. By combining this device with a multi-angle laser light scattering photometer (MALS) and a differential refractometer (RI), the light scattering intensity and refractive index difference of the molecular chain solution size-classified with the GPC device are measured according to the melting time, thereby determining the molecular weight of the solute. and its content are sequentially calculated, and finally the absolute molecular weight distribution and absolute average molecular weight value of the polymer material are obtained.

In addition, the measurement solvent of the GPC-MALS method is not particularly limited as long as the acrylic rubber veil of the present invention can be dissolved and measured, but a dimethylformamide solvent is suitable. The dimethylformamide-based solvent used is not particularly limited as long as it contains dimethylformamide as a main component, but the ratio of 100% dimethylformamide or dimethylformamide in the dimethylformamide-based solvent is 90% by weight, preferably 95%. % by weight, 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. When the glass transition temperature is set to be equal to or higher than the above lower limit, oil resistance and heat resistance can be further improved, and when the glass transition temperature is set to be equal to or lower than the upper limit, workability, crosslinkability and cold resistance are further improved.

<Acrylic rubber veil>

The acrylic rubber veil of the present invention has at least one reactive group selected from the group consisting of the carboxyl group, epoxy group and chlorine atom, and is preferably made of the acrylic rubber, and has specific specific gravity, ash content, gel amount, and gel amount variation. characterized by The acrylic rubber content in the acrylic rubber veil is not particularly limited, but is usually 90% by weight or more, preferably 93% by weight or more, more preferably 95% by weight or more, particularly preferably 97% by weight or more, and most preferably 99.85% by weight or more.

The ash content of the acrylic rubber veil of the present invention is 0.2% by weight or less, preferably 0.15% by weight or less, preferably 0.14% by weight or less, more preferably 0.13% by weight or less, storage stability when within this range, Water resistance, strength characteristics and processability are highly balanced and suitable.

The lower limit of the ash content 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 0.0001% by weight or more, preferably 0.0005% by weight or more, more preferably 0.001% by weight or more, especially When it is preferably 0.005% by weight or more, and most preferably 0.01% by weight or more, it is suitable because the metal adhesion of rubber is reduced and workability is excellent.

The amount of ash when the acrylic rubber veil of the present invention is highly balanced in storage stability, water resistance, strength characteristics, processability and workability is usually 0.0001 to 0.5% by weight, preferably 0.0005 to 0.3% by weight, more preferably 0.001% by weight. to 0.2% by weight, particularly preferably from 0.005 to 0.15% by weight, most preferably from 0.01 to 0.13% by weight.

The total amount of sodium, magnesium, calcium, phosphorus, and sulfur 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 50% by weight or more, preferably 60% by weight or more, more preferably When it is preferably 70% by weight or more, particularly preferably 80% by weight or more, and most preferably 90% by weight or more, the water resistance of the acrylic rubber veil is highly improved and is suitable. In addition, when the total amount of sodium, magnesium, calcium, phosphorus and sulfur in the ash of the acrylic rubber veil of the present invention is within this range, metal adhesion is reduced and workability is excellent, which is suitable.

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 water resistance, strength characteristics and workability of the acrylic rubber veil are highly balanced and suitable. In addition, when the total amount of magnesium and phosphorus in the ash content of the acrylic rubber veil of the present invention is within this range, metal adhesion is reduced and workability is excellent, which 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 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 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 the range is 1.2, more preferably 0.45 to 1, particularly preferably 0.5 to 0.8, and most preferably 0.55 to 0.7, the water resistance, strength characteristics and workability of the acrylic rubber veil are highly balanced and suitable.

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 the acrylic rubber veil of the present invention, an anionic emulsifier, a cationic emulsifier, or a nonionic emulsifier, preferably an anionic emulsifier, more preferably a phosphoric acid ester salt or a sulfuric acid ester salt is used as an emulsifier in the emulsion polymerization described later. In addition to water resistance and strength characteristics, it is suitable because it can highly improve mold releasability and workability. 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. And workability can be more highly balanced, so it is suitable.

The acrylic rubber veil of the present invention, when a metal salt, preferably an alkali metal salt or a periodic table group 2 metal salt, is used as a coagulant described later, in addition to water resistance and strength characteristics, mold release properties and processability can be highly improved, so it is suitable. 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. and workability are more highly balanced and suitable.

The gel amount of the acrylic rubber veil of the present invention, in terms of methyl ethyl ketone insoluble content, is 30% by weight or less, preferably 20% by weight or less, more preferably 15% by weight or less, particularly preferably 10% by weight or less, most preferably 10% by weight or less. When it is preferably 5% by weight or less, workability at the time of kneading such as Banbury is highly improved and is suitable.

In the acrylic rubber veil of the present invention, the value when the gel amount in the acrylic rubber veil is randomly sampled at a plurality of points and the deviation is measured is all of the values when measured within the range of (average value ± 5) weight%. to be characterized Here, the "method of measuring the amount of gel at random by sampling at a plurality of points" refers to a method of measuring variation in the amount of gel by, for example, sampling at random at 20 points from within a large veil. In the method according to the present application (melt-kneading in a screw-type twin-screw extrusion dryer in a substantially water-free state (less than 1% by weight), melt-kneading is not performed as a specific effect, the amount of gel in the bale is There are things that are disturbed and do not fall within this range. In the present invention, the value is, when all 20 points fall within the range of (average value ± 5) weight%, preferably, when all 20 points fall within the range of (average value ± 3) weight%, there is no variation in processability, and the rubber mixture However, various physical properties of cross-linked rubber are stabilized and suitable. On the other hand, when the gel amount of the acrylic rubber veil is arbitrarily measured at 20 points, the fact that all 20 points fall within the range of the average value ± 5 means that the value measured within the range of (average value - 5) to (average value + 5) weight% 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 has Banbury processability and strength characteristics when the hydrous crumb generated in the solidification reaction is melt-kneaded and dried in a state in which water is almost removed (moisture content less than 1% by weight) by a screw-type twin screw extrusion dryer. This 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 stability of crosslinking properties of crosslinked products are highly balanced and suitable. When the specific gravity of the acrylic rubber veil is excessively small, it indicates that the amount of air mixed in the acrylic rubber veil is large, and it is not preferable because it greatly affects storage stability including oxidative degradation and the like.

On the other hand, the specific gravity of the acrylic rubber veil 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, and is usually measured according to JIS K6268 Crosslinked Rubber-Method A of Density Measurement It will be.

In the acrylic rubber veil of the present invention, the hydrous crumb produced in the solidification reaction is dried under reduced pressure by a screw-type twin-screw extrusion dryer, or melt-kneaded and dried under reduced pressure. It is suitable because it is particularly excellent and highly balanced.

The complex viscosity ([η] 60°C) of the acrylic rubber veil of the present invention at 60°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 1,000. When in the range of 10,000 [Pa s], more preferably 2,000 to 5,000 [Pa s], particularly preferably 2,500 to 4,000 [Pa s], and most preferably 2,500 to 3,000 [Pa s] It is suitable because it has excellent processability, oil resistance and shape retention.

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 1,500 to 6,000 [Pa s], preferably 2,000 to 5,000 [Pa s], more preferably 2,300 to 4,000 [Pa s], particularly preferably 2,500 to 3,500 [Pa s], most preferably 2,500 to 3,000 [Pa s] It is suitable because it has excellent processability, oil resistance and shape retention.

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, more preferably 0.7 or more, particularly preferably 0.8 or more, and most preferably 0.83 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 0.5 to 0.99, preferably 0.6 to 0.98, more preferably 0.7 to 0.97, particularly preferably 0.8 to 0.96, and most preferably 0.85 to 0.95 in the range of workability, oil resistance, and shape Retention is highly balanced and suitable.

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 pH 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 6 or less, preferably 3 to 6, and more preferably in the range of 3 to 5 to preserve the acrylic rubber veil. The stability is highly improved and suitable.

The Mooney viscosity (ML1+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, and more preferably 25 to 150. When it is in the range of 70, the processability 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, and the width is usually 100 to 800 mm, preferably 200 to 500 mm, more preferably 250 to 450 mm, 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 It is appropriate to be in the range of 150 to 250 mm. 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 is not particularly limited. For example, an acrylic rubber monomer component containing a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom is mixed with water and an emulsifier. A step of emulsifying with;

An emulsion polymerization step of obtaining an emulsion polymerization solution by initiating a polymerization reaction and performing an emulsion polymerization reaction in the presence of a redox catalyst containing an inorganic radical generator and a reducing agent;

A coagulation step of adding the obtained emulsion polymerization liquid to a coagulating liquid stirred at a circumferential speed of 1 m/s or more and coagulating it to generate a hydrous crumb;

A cleaning step of washing the generated hydrous crumb with hot water;

A step of dewatering the washed hydrous crumb to a moisture content of 1 to 40% by weight in a dehydration barrel using a dehydration barrel having a dehydration slit, a drying barrel under reduced pressure, and a screw-type twin-screw extrusion dryer having a die at the tip;

A drying step of drying to less than 1% by weight in a drying barrel;

A molding step of extruding the sheet-shaped dry rubber from a die;

Lamination process in which extruded sheet-like dry rubber is laminated after cutting

It can be efficiently produced by a method for producing an acrylic rubber veil comprising a.

(monomer component)

The monomer component comprising a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom used in the present invention is not particularly limited, but preferably (meth)acrylic acid alkyl ester and (meth) At least one (meth)acrylic acid ester selected from the group consisting of acrylic acid alkoxyalkyl esters, a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, and other monomers copolymerizable as necessary. It consists of, and is the same as the examples and preferred ranges of the monomer components previously 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. It is suitable because it 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 It is suitable because it can highly balance releasability and workability.

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

As said alkyloxy polyoxyalkylene phosphate ester salt, the alkyloxy polyoxyethylene phosphate ester salt, the alkyloxy polyoxypropylene phosphate ester salt, etc. are mentioned, for example, Among these, the alkyloxy polyoxyethylene phosphate ester 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, Tridecyloxytetraoxyethylene Phosphate, Tetradecyloxytetraoxyethylene Phosphate, Hexadecyloxytetraoxyethylene Phosphate, Octadecyloxytetraoxyethylene Phosphate, Octyloxypentaoxyethylene Phosphate, Decyloxy Pentaoxyethylene Phosphate, Dodecyloxypentaoxyethylene Phosphate, Tridecyloxypentaoxyethylene Phosphate, Tetradecyloxypentaoxyethylene Phosphate, Hexadecyloxypentaoxyethylene Phosphate, Octadecyloxypentaoxyethylene Phosphate , octyloxyhexaoxyethylene phosphate ester, decyloxyhexaoxyethylene phosphate ester, dodecyloxyhexaoxyethylene phosphate ester, tridecyloxyhexaoxyethylene phosphate ester, tetradecyloxyhexaoxyethylene phosphate ester, hexadecyloxyhexaoxyethylene Phosphate 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 , 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, tridecyloxyoctaoxyethylene 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 salt 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 Phosphate ester, hexylphenyloxypentaoxyethylene phosphate ester, nonylphenyloxypentaoxyethylene phosphate ester, dodecylphenyloxypentaoxyethylene phosphate ester, methylphenyloxyhexaoxyethylene phosphate ester, ethylphenyloxyhexaoxyethylene phosphate ester, butylphenyl Oxyhexaoxyethylene Phosphate, Hexylphenyloxyhexaoxyethylene Phosphate, Nonylphenyloxyhexaoxyethylene Phosphate, Dodecylphenyloxyhexaoxyethylene Phosphate, Methylphenyloxyhexaoxyethylene Phosphate, 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 salt include methylphenyloxytetraoxypropylene phosphate ester, ethylphenyloxytetraoxypropylene phosphate ester, butylphenyloxytetraoxypropylene phosphate ester, hexylphenyloxytetraoxypropylene phosphate ester, and nonyl. Phenyloxytetraoxypropylene Phosphate, Dodecylphenyloxytetraoxypropylene Phosphate, Methylphenyloxypentaoxypropylene Phosphate, Ethylphenyloxypentaoxypropylene Phosphate, Butylphenyloxypentaoxypropylene Phosphate, Hexylphenyloxypentaoxypropylene Phosphate 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 ester, hexylphenyloxyoctaoxypropylene phosphate ester, nonylphenyloxyoctaoxypropylene phosphate ester, and dodecylphenyloxyoctaoxypropylene phosphate ester; 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 sulfate 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. It is sodium uryl sulfate.

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 stearate; 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 component. 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.

(inorganic radical generator)

As the polymerization catalyst used in the present invention, a redox catalyst composed of an inorganic radical generating agent and a reducing agent is used. In particular, by using an inorganic radical generating agent, the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of acrylic rubber can be widened, so that the processability of the acrylic rubber veil roll, etc. is highly improved. It is suitable because it can be improved.

The inorganic radical generating agent is not particularly limited as long as it is commonly used in emulsion polymerization, and examples thereof include persulfates such as sodium persulfate, potassium persulfate and ammonium persulfate, hydrogen peroxide, and the like. Among these, persulfates are Preferably, potassium persulfate and ammonium persulfate are more preferable, and potassium persulfate is particularly preferable.

These inorganic 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, more 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 0.25 parts by weight, particularly preferably in the range of 0.01 to 0.21 parts by weight, and most preferably in the range of 0.1 to 0.2 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 workability, roll workability and strength characteristics of the obtained 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, and 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.

The reducing agent other than the metal ion compound in a reduced state used in the present invention is 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 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 phosphite, phosphorous acid of phosphorous acid or potassium hydrogen phosphite, or a salt thereof; pyrophosphorous acid 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 in the range of 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. is 5 to 30 ° C., particularly preferably controlled to 10 to 25 ° C., the strength characteristics of the acrylic rubber veil produced 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 possible to produce an acrylic rubber in which a high molecular weight component and a low molecular weight component are divided by batchwise post-adding during polymerization without initially adding a chain transfer agent, and furthermore, the strength characteristics and Workability at the time of kneading, such as rolls, is highly balanced, so it is 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, it is suitable because it can stably exhibit the effect of a chain transfer agent and can highly improve the workability of the acrylic rubber produced, such as a roll.

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, the strength characteristics and roll processability 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 acrylic rubber produced has a high molecular weight component and a low molecular weight component, and the molecular weight distribution is set within a specific range to obtain acrylic It is suitable because it can highly balance the strength characteristics of rubber veils and workability of rolls.

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 strength characteristics of the acrylic rubber veil produced at the time of the second run and the workability of rolls.

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. 30 to 200 minutes after the start of polymerization, particularly preferably 35 to 150 minutes, most preferably 40 to 120 minutes after the start of polymerization, the strength characteristics of the acrylic rubber veil and the workability of rolls can be highly balanced, making it suitable for do.

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, the strength characteristics and roll processability of the acrylic rubber veil produced can be highly balanced. It is suitable.

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 for the redox catalyst can be added post-added during polymerization, and thus, the strength characteristics of the acrylic rubber veil and the workability of rolls can be highly balanced, which is suitable.

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 0.001 to 0.5 parts by weight, particularly preferably 0.005 to 0.1 parts by weight, most preferably 0.01 to 0.05 parts by weight, the productivity of acrylic rubber production is excellent and the strength characteristics and processability of the acrylic rubber veil produced are highly It is suitable because it can be 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"/"post-added ascorbic acid or a salt thereof 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 processability 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 initiation of polymerization, preferably 1 to 3 hours after initiation of polymerization, more preferably 1.5 to 2.5 hours. At the same time, the productivity of acrylic rubber production is excellent and it is suitable because it can highly balance the strength characteristics of the acrylic rubber veil and the workability of the roll.

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 in the range of 0.001 to 0.03 parts by weight, it is suitable because the strength characteristics of the acrylic rubber veil and workability such as rolls can be highly balanced.

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 does not have the smell of monomers. 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 adding the obtained emulsion polymerization solution to a coagulation solution stirred at a circumferential speed of 1 m/s or more and coagulating it to form a hydrous crumb.

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

Although the coagulant liquid used is usually used as an aqueous solution, the coagulant for the aqueous solution 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, when a magnesium salt is used, the water resistance, strength characteristics, mold release properties, and workability of the obtained acrylic rubber can be highly balanced, so it is suitable.

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.

Examples of other metal salts include 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, and nickel nitrate. , 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 component. 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 when the acrylic rubber veil is crosslinked can be highly improved while sufficiently coagulating the acrylic rubber.

The coagulant concentration of the coagulant liquid used is usually 0.1 to 20% by weight, preferably 0.5 to 15% by weight, more preferably 1 to 10% by weight, particularly preferably 1.5 to 5% by weight. It is suitable because it can uniformly focus the grain size of hydrous crumbs 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.

In the present invention, as a method of coagulating the emulsion polymerization liquid into a coagulating liquid, it is characterized in that the emulsion polymerization liquid is added to the coagulating liquid stirred at a circumferential speed of 1 m/s or more.

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 revolutions, the number of rotations that are vigorously stirred to a certain extent is suitable because the grain size of the resulting hydrous crumbs can be made small and uniform. It can be carried out, and the control of the coagulation reaction can be made easier by setting it 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 washing step in the production method of the acrylic rubber veil of the present invention is a step of washing the hydrous crumb generated in the solidification reaction with hot water.

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 hot water added for washing is not particularly limited, but the amount per water washing is usually 50 parts by weight or more, preferably 50 to 15,000 parts by weight, more preferably 100 to 15,000 parts by weight, based on 100 parts by weight of the monomer components. When it is in the range of 10,000 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 hot water to be used is not particularly limited, but is usually 40 ° C. or higher, preferably 40 to 100 ° C., more preferably 50 to 90 ° C., and especially 60 to 80 ° C., the cleaning efficiency can be significantly increased. Optimal. 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 (washing with water) is also 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 sheet, it is preferable to increase the number of times of washing with water, but as described above, setting the shape of the hydrous crumbs and the diameter of the hydrous crumbs within a specific range, and/or setting the washing temperature 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, providing a water removal step in which free water is separated from the water-containing crumb after washing with a water remover is suitable for increasing the dewatering efficiency.

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 eye 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 is efficient. I can do it. 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 step 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, and molding steps, is not particularly limited, but is usually 40 ° C. or higher, preferably 40 to 100 ° C., more preferably 50 to 90 ° C. ℃, particularly preferably in the range of 55 to 85 ℃, most preferably 60 to 80 ℃, the specific heat is high at 1.5 to 2.5 KJ / kg K, like the acrylic rubber constituting the acrylic rubber veil of the present invention. It is suitable because it can dehydrate and dry water-containing crumb, which is difficult to increase, efficiently using a screw-type twin-screw extrusion dryer.

(Dehydration/drying/forming process)

The dewatering/drying/molding step in the method for producing an acrylic rubber veil of the present invention includes a dewatering barrel having a dewatering slit, a drying barrel under reduced pressure, and a die at the tip of the washed, preferably water-containing crumb. It is a process of extruding sheet-shaped dry rubber from a die by dehydrating the water content to 1 to 40% by weight with a dehydration barrel using a screw-type twin-screw extrusion dryer and then drying to less than 1% by weight with a drying barrel.

(Dehydration of hydrous crumb in dewatering barrel)

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 according to 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, loss of water crumb is small and water Suitable for efficient dehydration of crumbs.

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 dehydrated 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 equipped with three or more dehydration barrels may be appropriately performed according to the purpose of use, but when reducing the amount of ash in a normally produced acrylic rubber sheet In the case of reducing the water content, the number of drain type barrels is increased, and the number of double steam type barrels is increased.

The set temperature of the dewatering 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 dewatering 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 dewatering 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 dehydration in which water is squeezed out of the water-containing crumb is not particularly limited, but is 1 to 40% by weight, preferably 5 to 40% by weight, more preferably 5 to 35% by weight, particularly preferably When is 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 performed 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.

In the case of dewatering 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 drainage 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 preliminary drying in the double steam type dewatering 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)

The drying of the hydrous crumb after dehydration is preferably performed in a drying barrel under reduced pressure using 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 can be further improved to a high degree 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 dried efficiently and the air in the acrylic rubber It is suitable because it can remarkably improve the storage stability of the acrylic rubber veil by removing the

The set temperature of the drying barrel may be appropriately selected, but is usually in the range of 100 to 250 ° C, preferably 110 to 200 ° C, more preferably 120 to 180 ° C, without deterioration or deterioration due to heat of acrylic rubber, and efficiency It is suitable because it can dry well and can reduce the amount of gel in the 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 dry barrels may be an approximate decompression degree in all the dry 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 the dried rubber is set to this value (a state in which water is almost removed) and melt-kneaded and extruded to increase the gel amount of the methyl ethyl ketone insoluble content of the acrylic rubber veil. It is suitable because it can be reduced. In the present invention, an acrylic rubber veil melt-kneaded or melt-kneaded and dried with a screw-type twin-screw extrusion dryer is suitable because both characteristics of strength 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 where the acrylic rubber does not substantially contain water is not particularly limited, but is usually 10 [1/s] or more , Preferably in the range of 10 to 400 [1 / s], more preferably in the range of 50 to 250 [1 / s] Storage stability, roll processability, Banbury processability, strength characteristics and compression set resistance of the obtained acrylic rubber veil The 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, roll processability, Banbury processability and strength characteristics are highly balanced and suitable.

(Extrusion of dry rubber from die part)

The dried rubber dehydrated and dried by 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. In particular, in the die portion, it is important that the acrylic rubber melt-kneaded without containing air is extruded into a sheet form without containing air as it is.

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 of dry rubber or deterioration due to heat.

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 More specifically, at 120 to 300 rpm, it is suitable because it can efficiently reduce the water content and gel amount of the acrylic rubber veil.

The extrusion amount (Q) of the screw type twin screw extrusion dryer used is not particularly limited, but is usually 100 to 1,500 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 revolutions (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.

In the present invention, in particular, the roll processability, Banbury processability and strength characteristics of the acrylic rubber bale obtained by drying the hydrous crumb under high share conditions using a screw-type twin screw extrusion dryer having two screws can be highly balanced. suitable

The maximum torque of the screw-type twin-screw extrusion dryer used is not particularly limited, but is usually 25 N m or more, preferably 30 N m or more, more preferably 35 N m or more, and particularly preferably 40 N m or more. It is more than N m. The maximum torque of the screw type twin screw extrusion dryer used in the present invention is also usually 25 to 125 N m, preferably 30 to 100 N m, more preferably 35 to 75 N m, particularly preferably When is in the range of 40 to 60 N m, it is suitable because it can highly balance the roll processability, 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 0.1 to 0.25 [kw h/kg] or more, preferably 0.13 to 0.23 [kw h/kg], more preferably 0.15 In the range of ~ 0.2 [kw h / kg], the roll processability, 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 0.2 to 0.6 [A h/kg] or more, preferably 0.25 to 0.55 [A h/kg], more preferably 0.35 In the range of ~ 0.5 [A h / kg], the roll processability, 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 40 to 150 [1/s] or more, preferably 45 to 125 [1/s], more preferably 50 to 100 [1/s]. /s], the storage stability, roll processability, 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, roll processability, Banbury processability and strength characteristics of the acrylic rubber veil obtained are highly balanced and 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, air is not mixed, the specific gravity can be increased, and the storage stability is highly improved, which is suitable. Sheet-like dry rubber extruded from a screw-type twin-screw extrusion dryer is usually cooled and cut to be used as an acrylic rubber sheet.

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 mm. In the range of ~25 mm, 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 is usually 1 to 30 mm, preferably 2 to 25 mm, when cooling efficiency is increased and productivity is significantly improved. mm, 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-like 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 sheet-shaped dry 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 sheet-shaped 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 4000 [Pa s], and most preferably 2500 to 3500 [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.

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 mixing 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, when it is in the range of 2500 to 7000 [Pa s], most preferably 2700 to 5500 [Pa s], it is suitable because it can be cut continuously without mixing 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 depending on the purpose of use, but is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more, particularly preferably 0.8 or more, and most preferably 0.85 or more, and the upper limit is usually When 0.98 or less, preferably 0.97 or less, more preferably 0.96 or less, particularly preferably 0.95 or less, and most preferably 0.93 or less, air entrainment is low, and cutting and productivity are highly balanced and 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, an air cooling method 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 cold 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 length to be cooled is not particularly limited, but is usually in the range of 5 to 500 m, preferably 10 to 200 m, and more preferably 20 to 100 m.

The cooling rate of the sheet-like dry rubber is not particularly limited, but 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. It is suitable because it is easy to cut at the time of application, air is not mixed in the molded article, and storage stability can be improved. 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, the scorch stability when an acrylic rubber veil is used as a rubber composition is remarkably 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.

The sheet-like acrylic rubber obtained in this way is superior in operability compared to crumb-like acrylic rubber, and is also excellent in roll processability, strength characteristics and compression set resistance, as well as storage stability, Banbury workability, crosslinkability and water resistance. , It can be used as it is or layered and veiled.

(Laminating process)

The acrylic rubber veil of the present invention can be obtained by laminating the sheet-like acrylic rubber (acrylic rubber sheet), and by laminating the sheet-like acrylic rubber, an acrylic rubber veil with less entrainment of air and excellent storage stability is obtained.

The lamination temperature of the sheet-like acrylic rubber is not particularly limited, but it is suitable when it is usually 30°C or higher, preferably 35°C or higher, and more preferably 40°C or higher, since air entrained during lamination can escape. 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 acrylic rubber.

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

<Rubber mixture>

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

The filler included in the rubber mixture is not particularly limited, but examples thereof include reinforcing fillers and non-reinforcing fillers. Preferably, when the reinforcing filler is used, roll processability of the rubber mixture, Banbury processability, and short time It is suitable because it has excellent crosslinkability 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. 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, barium sulfate and the like.

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

The crosslinking agent used in the rubber mixture 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 either a polyvalent compound or a monovalent compound, but a polyvalent compound having two or more reactive groups is preferable. The crosslinking agent may be any of an ion crosslinkable compound or a radical crosslinkable compound, but is preferably an ion crosslinkable compound.

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 mixture has excellent roll processability, Banbury processability, and crosslinkability in a short time, and the crosslinked product has highly excellent water resistance, strength characteristics, and compression set resistance. So it is particularly suitable. The "ion" of ionic crosslinkability or polyvalent ion is an ion reactive ion, for example, an ionic reaction with an ionic reactive group of an ion reactive group-containing monomer of the acrylic rubber, and there is no particular limitation, but preferably an amine ion-crosslinkable organic compounds having ion-reactive groups such as groups, epoxy groups, carboxyl groups, and thiol groups.

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. The "ion" of ionic crosslinkability or polyvalent ion is one that ionically reacts with the ionically reactive group of the ionically reactive group-containing monomer of the acrylic rubber, and is not particularly limited. For example, an amine group, an epoxy group, a carboxyl group, a thiol group, etc. can be heard

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 preferably used in combination with a carboxyl group-containing acrylic rubber sheet or 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, based on 100 parts by weight of the acrylic rubber veil of the present invention. Preferably it is 0.1-5 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.

An antiaging agent may be added to the rubber mixture of the present invention, if necessary. 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 blending amount is 0.01 to 15 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the acrylic rubber veil of the present invention. More preferably, it is the range of 1-5 parts by weight.

As the rubber component serving as the main component of the rubber mixture 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. .

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 amount of other rubber components used is appropriately selected within a range that does not impair the effects of the present invention, for example, usually 70 parts by weight or less, preferably 50 parts by weight, based on 100 parts by weight of the acrylic rubber veil of the present invention. or less, more preferably 30 parts by weight or less, particularly preferably 20 parts by weight or less, and most preferably 10 parts by weight or less.

The rubber mixture of the present invention contains the acrylic rubber veil, filler and crosslinking agent of the present invention as essential components and, if necessary, an anti-aging agent or other rubber components, and furthermore, if necessary, it 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 optionally be 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 mixture of the present invention, a method of mixing the acrylic rubber veil of the present invention, a filler, a crosslinking agent, an anti-aging agent, other rubber components, and other compounding agents that may be contained as necessary, and mixing For this, any means used in the conventional rubber processing field, for example, open rolls, Banbury mixers, various types of kneaders, and the like can be used. The mixing order of each component may be carried out in the usual order performed in the field of rubber processing. For example, after sufficiently mixing components that are difficult to react or decompose with heat, a crosslinking agent that is a component that is easily reacted or decomposed with heat, etc. It is preferable to mix 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 mixture.

The cross-linked rubber product of the present invention is molded using a rubber mixture of the present invention with a molding machine corresponding to a desired shape, such as an extruder, injection molding machine, compressor or roll, and heated to perform a cross-linking reaction. It can be manufactured by fixing the shape as a cross-linked 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, etc. 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 inorganic 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 control unit so as 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 solution 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 cleaning 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 by 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 by 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 structure, high shear can be applied to acrylic rubber and drying can be performed, which is suitable. 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 equipped 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) that controls the set temperature of each heating means corresponding to each of the barrels 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 the drying process It can be set to a number according to the water content of the water-containing crumb of the acrylic rubber.

For example, the number of installation of the supply barrel of the supply barrel part 52 becomes 1-3, for example. In addition, 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, the number of dry barrels installed in the dry barrel part 54 is preferably 2 to 10, for example, and more preferably 3 to 8.

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.

The rotational directions of the pair of screws may be in the same direction or in different directions, but from the viewpoint of self-cleaning performance, it is preferable to 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 in 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 dehydration of the moistened crumbs. From the point which can be made, Preferably it is 0.1-1 mm, and it is more preferable if it is 0.2-0.6 mm.

Removal of water from the water-containing crumbs in each dewatering barrel 53a to 53c of the dewatering barrel part 53 is carried out in a liquid phase from each of the dewatering slits 56a, 56b, and 56c, and in a 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 depending on 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 above-mentioned dewatering/drying step. The set temperature of the dewatering barrel for dehydration in the state is usually 60 to 120 ° C, preferably 70 to 110 ° C, more preferably 80 to 100 ° C, and the set temperature of the dehydration barrel for dehydration in the double steam state is usually 100 ° C. to 150°C, preferably 105 to 140°C, more preferably 110 to 130°C.

The drying barrel part 54 is a region for drying the dehydrated crumbs under reduced pressure. Of 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 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 portion 54, the set temperature in all the drying barrels 54a to 54h may be approximated or different, but the upstream side (dewatering barrel portion 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. The acrylic rubber dried by the drying barrel part 54 passes through the discharge port of the die 59, and is extruded into a shape according to a predetermined nozzle shape. The acrylic rubber passing through the die 59 can be molded into various shapes such as particulate, columnar, round bar, 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 moisture 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. From the point which can reduce, Preferably it is 50-750 rpm, More preferably, it is 100-500 rpm, and 120-300 rpm is the most preferable.

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) of 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, and 4 to 6 are particularly preferred.

The maximum torque in the barrel unit 51 is not particularly limited, but is usually in the range of 30 to 100 N·m, preferably 35 to 75 N·m, and more preferably 40 to 60 N·m.

The specific power in the barrel unit 51 is not particularly limited, but is usually 0.1 to 0.25 [kw h/kg] or more, preferably 0.13 to 0.23 [kw h/kg], more preferably 0.15 to 0.2 [kw h/kg]. kw·h/kg].

The specific power in the barrel unit 51 is not particularly limited, but is usually 0.2 to 0.6 [A h/kg] or more, preferably 0.25 to 0.55 [A h/kg], more preferably 0.35 to 0.5 [A h/kg]. A h/kg].

The shear rate in the barrel unit 51 is not particularly limited, but is usually 40 to 150 [1/s] or more, preferably 45 to 125 [1/s], more preferably 50 to 100 [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 adopt 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 dried 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 of the conveyor 61 and the cooling means 65 of the transport type cooling device 60 (the length of the portion where the cooling wind can be blown) L1 is not particularly limited, but is, for example, 10 to 100 m, preferably. is between 20 and 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 It may be appropriately adjusted according to the discharge rate of the sheet-shaped dry rubber 10 discharged from the , the target cooling rate or cooling time, for example, 10 to 100 m/hr, more preferably 15 to 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 extruded from a screw extruder 5 and cooled by a 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. Although the weight or shape of the acrylic rubber bale produced by the baling device 7 is not particularly limited, for example, a substantially rectangular parallelepiped acrylic rubber bale of about 20 kg is manufactured.

The baling device 7 may have, for example, a baler, and may manufacture an acrylic rubber bale 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 an acrylic rubber veil in which the sheet-like dry rubber 10 is laminated. 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 the polymerization conversion rate was approximately 100%, in which no unreacted monomers could be confirmed, so the content ratio of each monomer unit in the rubber was the same as the amount of each monomer used. did

[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 rubber sample in acetone and performing potentiometric titration with a potassium hydroxide solution.

(2) The amount of epoxy group was calculated by dissolving a rubber 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 rubber 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]

The amount (ppm) of each component in the acrylic rubber veil ash was measured by XRF using a ZSX Primus (manufactured by Rigaku) by pressing the ash collected at the time of measuring the ash amount above with a suitable filter paper of φ 20 mm.

[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

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). Specifically, a multi-angle laser light scattering photometer (MALS) and a differential refractometer (RI) are combined with a GPC (Gel Permeation Chromatography) device, and the light scattering intensity and refractive index difference of the molecular chain solution size-classified by the GPC device are elution By measuring over time, 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 (φ7.8 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 the sample (acrylic rubber veil), and gently stirred at room temperature (dissolution was observed). Thereafter, 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 separated by filtration of insoluble components for methyl ethyl ketone using an 80 mesh wire mesh, the filtrate, i.e. , The dry solid content (Yg) obtained by evaporating and drying the filtrate in which only the rubber component soluble in methyl ethyl ketone was dissolved was solidified was weighed and calculated by the following formula.

Methyl ethyl ketone insoluble content (%) = 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. The base of the test piece is suspended so that it is 25 mm above the distribution dish for chemical balance, and the mass (m1) of the test piece is measured twice to mg in the air.

(2) Next, a beaker with a capacity of 250 cm ³ placed on a distribution dish for chemical balance is filled with distilled water cooled to a standard temperature after boiling, the test piece is immersed in it, and air bubbles adhering to the surface of the test piece are removed. and observe the movement of the scale guide for several seconds to confirm that the guide does not slowly shake due to convection, and measure the mass (m2) of the test piece in water twice in mg units.

(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 veil in 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 (ML1+4, 100℃)]

The Mooney viscosity (ML1+4, 100°C) was measured according to the JIS K6300 uncrosslinked rubber physical test method.

[Evaluation of variance in gel amount]

To evaluate the deviation of the gel amount of the rubber sample, the gel amount of 20 points selected at random 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

[Crosslinkability]

The crosslinkability of a rubber sample is the rate of change between the breaking strength of a crosslinked rubber product subjected to secondary crosslinking for 2 hours and the breaking strength of a crosslinked rubber product subjected to 4 hours ((break strength of a crosslinked rubber product for 4 hours/break strength of a crosslinked rubber product for 2 hours) × 100) was calculated and judged according to the following criteria.

◎: The breaking strength change rate is less than 10%

×: The breaking strength change rate is 10% or more

[Roll machinability]

The roll processability of the rubber sample was evaluated according to the following criteria by observing the roll-wrapability and rubber state when the rubber sample was roll-kneaded.

◎: Kneading is easy, it is easy to wind around a roll, and the surface of the rubber composition after kneading is smooth without being seen to fall off the roll.

○: Kneading is easy, and it is easy to wind around the roll, so that falling off the roll is not observed, and a part of the surface of the rubber composition after kneading is slightly uneven.

□: Kneading is easy, roll-wrapability is excellent, and the surface of the rubber composition after kneading is somewhat uneven.

△: Easy kneading, somewhat poor roll-wrapability, rough surface of rubber composition after kneading

×: A load is applied to kneading and the roll winding property is poor

[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 Comparative Example 2 was evaluated with an index of 100 (the smaller the index, the better the workability).

[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, Comparative Example 2 was 100 (The smaller the index, the better the storage stability).

[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, and the volume change rate before and after immersion was calculated according to the following formula, Comparative Example 2 Evaluation was made with an index of 100 (the smaller the index, the better the water resistance).

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

[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 placing at 175° C. for 90 hours in a state in which the cross-linked rubber of the rubber sample was compressed by 25% according to JIS K6262.

◎: compression set is less than 15%

×: compression set is 15% or more

[Evaluation of state physical properties]

The 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 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 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, 74.5 parts of ethyl acrylate, 17 parts of n-butyl acrylate, 7 parts of methoxyethyl acrylate and 1.5 parts of mono n-butyl fumarate as monomer components Part, 1.8 parts of tridecyloxyhexaoxyethylene phosphate sodium salt as an emulsifier 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 inorganic A polymerization reaction was initiated by adding 0.21 parts of potassium persulfate 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, 0.017 part of n-dodecylmercaptan 50 minutes after the start of the reaction, 0.017 part of n-dodecylmercaptan after 100 minutes, And after 120 minutes, 0.017 part of n-dodecylmercaptan and 0.4 part of sodium L-ascorbate were added to continue the polymerization reaction, and when the polymerization conversion reached approximately 100%, hydroquinone was added as a polymerization terminator to carry out the polymerization reaction. was stopped to obtain an emulsion polymerization solution.

Then, 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 blade of the stirring device (circumferential speed: 3.1 m / s), 2% aqueous magnesium sulfate solution (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, dehydrated and dried to extrude sheet-like dry 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. In Table 2-1, 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 are shown.

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): 132 mm

·Overall length of screw (L): 4620 mm

·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: 15 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 their results are shown in Table 2-2. In addition, the variation in gel amount and storage stability of the acrylic rubber veil (A) were tested to determine the rate of change in water content.

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). BIT at this time was measured to evaluate the Banbury workability of acrylic rubber, 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" was blended and mixed (second stage mixing) to obtain a rubber mixture. The roll workability at this time was evaluated and the results are shown in Table 2-2.

[Table 1]

The obtained rubber mixture 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. , and further heated at 180° C. for 2 hours to perform secondary crosslinking, thereby obtaining a sheet-like crosslinked rubber product. Then, a test piece of 3 cm × 2 cm × 0.2 cm was cut out from the obtained cross-linked rubber sheet, and water resistance, compression set resistance, and normal physical properties were evaluated. In addition, the state physical properties of the crosslinked sheet-shaped rubber after the secondary crosslinking were further performed for 2 hours were measured to evaluate the crosslinkability. Their results are shown in Table 2-2.

[Example 2]

Examples except that 4.5 parts of ethyl acrylate, 64.5 parts of n-butyl acrylate, 29.5 parts of methoxyethyl acrylate and 1.5 parts of monon-butyl fumarate as monomer components, and 1.8 parts of nonylphenyloxyhexaoxyethylene phosphate sodium salt as an emulsifier. In the same manner as in 1, an acrylic rubber veil (B) was obtained and each property was evaluated, and the 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 amount of potassium persulfate was changed to 0.2 part and the post-addition of n-dodecylmercaptan was changed to 0.0072 part after 50 minutes and 0.0036 part after 100 minutes twice. obtained and evaluated each characteristic, and their results are shown in Table 2-2.

[Example 4]

Example 3 except that 4.5 parts of ethyl acrylate, 64.5 parts of n-butyl acrylate, 29.5 parts of methoxyethyl acrylate and 1.5 parts of mono n-butyl fumarate, and 1.8 parts of octyloxyhexaoxyethylene phosphate sodium salt as the emulsifier were used as monomer components. In the same manner as above, an acrylic rubber veil (D) was obtained and each property was evaluated, and the results are shown in Table 2-2.

[Example 5]

The monomer components are 28 parts of ethyl acrylate, 38 parts of n-butyl acrylate, 27 parts of methoxyethyl acrylate, 5 parts of acrylonitrile and 2 parts of allylglycidyl ether, and the maximum torque of the screw type twin screw extrusion dryer is 45 N m In the same manner as in Example 1 except for changing to, an acrylic rubber veil (E) was obtained and each characteristic (the compounding agent was changed to “Formulation 2”) was evaluated, and their results are shown in Table 2-2.

[Example 6]

An acrylic rubber veil (F) was obtained in the same manner as in Example 5 except that the monomer components were changed to 48.5 parts of ethyl acrylate, 50 parts of n-butyl acrylate, and 1.5 parts of monon-butyl fumarate, and each characteristic (mixing agent, " Formulation 1") were evaluated, and their results are shown in Table 2-2.

[Example 7]

An acrylic rubber veil (G) was obtained in the same manner as in Example 5 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. Formulation 3”) were evaluated, and their results are shown in Table 2-2.

[Example 8]

The monomer components are 28 parts of ethyl acrylate, 38 parts of n-butyl acrylate, 27 parts of methoxyethyl acrylate, 5 parts of acrylonitrile and 2 parts of allylglycidyl ether, and the maximum torque of the screw type twin screw extrusion dryer is 45 N m In the same manner as in Example 3 except for changing to, an acrylic rubber veil (H) was obtained and each characteristic (the compounding agent was changed to “Formulation 2”) was evaluated, and their results are shown in Table 2-2.

[Example 9]

An acrylic rubber veil (I) was obtained in the same manner as in Example 8 except that the monomer components were changed to 48.5 parts of ethyl acrylate, 50 parts of n-butyl acrylate, and 1.5 parts of monon-butyl fumarate. Formulation 1") were evaluated, and their results are shown in Table 2-2.

[Example 10]

An acrylic rubber veil (J) was obtained in the same manner as in Example 8 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. Formulation 3”) were evaluated, and their results are shown in Table 2-2.

[Comparative Example 1]

In a mixing vessel equipped with a homomixer, 46 parts of pure water, 42.2 parts of ethyl acrylate as monomer components, 35 parts of n-butyl acrylate, 20 parts of methoxyethyl acrylate, 1.5 parts of acrylonitrile and 1.3 parts of vinyl chloroacetate as emulsifiers, tri 1.8 parts of decyloxyhexaoxyethylene 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 A polymerization reaction was initiated by adding 0.22 parts of potassium sulfate. The temperature in the polymerization reaction tank was maintained at 23° C., and the remainder of the monomer emulsion was continuously added dropwise over 3 hours. When the polymerization conversion reached approximately 100%, hydroquinone was added as a polymerization terminator to stop the polymerization reaction and emulsify A polymerization solution was obtained.

Then, the emulsion polymerization solution was heated to 80° C., and while stirring at 100 revolutions of the stirring blades of the stirring device (circumferential speed: 0.5 m/s), a 0.7% aqueous solution of magnesium sulfate (coagulant solution using magnesium sulfate as a coagulant) was added thereto. The polymer was coagulated by addition, and a coagulated slurry containing acrylic rubber crumb and water as a coagulated product was obtained. 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 water-containing crumb after washing was dried to a water content of 0.4% using a hot air dryer at 160°C to obtain crumb-like acrylic rubber (K). Each characteristic of the obtained crumb-like acrylic rubber (K) was evaluated and shown in Table 2-2.

[Comparative Example 2]

The emulsifier was changed to 0.709 parts of sodium lauryl sulfate and 1.82 parts of polyoxyethylene dodecyl ether, the coagulation liquid was changed to 0.7% sodium sulfate aqueous solution, and the washing method was 194 industrial water for 100 parts of hydrous crumb after coagulation reaction Part was added, and after stirring in the coagulation tank at 25°C for 5 minutes, the water-containing crumb was washed 4 times to drain water from the coagulation tank, and then 194 parts of an aqueous solution of sulfuric acid having a pH of 3 was added and stirred at 25°C for 5 minutes. After that, crumb-like acrylic rubber (L) was prepared in the same manner as in Comparative Example 1 except that water was discharged from the coagulation tank, pickling was performed once, and then 194 parts of pure water was added to perform pure water washing once. got it Each characteristic of the obtained crumb-like acrylic rubber (L) was evaluated, and the results are shown in Table 2-2.

[Table 2-1]

[Table 2-2]

From Table 2-1 and Table 2-2, it has at least one reactive group selected from the group consisting of carboxyl group, epoxy group and chlorine atom of the present invention, specific gravity is 0.9 or more, ash content is 0.15% by weight or less, gel amount is Acrylic rubber veils (A) to (J) of 30% by weight or less, and the value when the gel amount is arbitrarily sampled at a plurality of points and the deviation is measured, and all of the above samplings measured within the range of the average value ± 5% by weight It can be seen that the state physical properties, including gel amount variation, Banbury processability, storage stability, crosslinkability, water resistance, compression set resistance, and strength characteristics, are excellent, and the roll processability is also remarkably excellent (Examples 1 to 3). 10).

From Table 2-2, the acrylic rubber veils (A) to (J) and crumb-like acrylic rubbers (K) to (L) prepared under the conditions of Examples and Comparative Examples of the present application are carboxyl groups, epoxy groups, chlorine atoms, etc. Since it has any ionic reactive group and the absolute molecular weight (Mn, Mw, Mz) measured by the GPC-MALS method has a certain size, it has properties including short-time crosslinking properties, compression set resistance and strength properties. It can be seen that all state physical properties are excellent (Examples 1 to 10 and Comparative Examples 1 to 2). However, it has been found that the crumb-like acrylic rubbers (K) to (L) are inferior in both gel amount variability, roll processability and Banbury processability, as well as poor water resistance and storage stability (Comparative Examples 1 and 2).

Regarding Banbury processability, it can be seen from Table 2-2 that the acrylic rubber veils (A) to (J) of the present invention having an overwhelmingly small amount of gel are excellent (comparison between Examples 1 to 10 and Comparative Examples 1 to 2). ). In this Example and Comparative Example, the polymerization conversion rate is emulsion-polymerized up to about 100% in order to increase the strength characteristics, but the gel amount of the methyl ethyl ketone insoluble content increases rapidly as the polymerization conversion rate increases, thereby deteriorating Banbury workability. In the present application, , By using a screw-type twin-screw extrusion dryer, dried to a state that does not contain water (less than 1% by weight), melt-kneaded, and rapidly increased methyl ethyl ketone insoluble gel amount is lost, resulting in high strength characteristics and Banbury workability. It was found that balance can be achieved, and since most of the methyl ethyl ketone insoluble gel amount is lost in the screw type twin screw extrusion dryer, there is little variation in the gel amount, and the Banbury processability and crosslinking properties are remarkably stabilized. In addition, although only overwhelmingly excellent data are shown in the present examples, BIT (Black Incorporation Time), which is an index of Banbury workability, and the gel amount of methyl ethyl ketone insoluble matter are on the line of a very high correlation coefficient, for example , The gel amount of the methyl ethyl ketone insoluble content of the crumb-like acrylic rubber directly dried in the same way as in Comparative Example 1 was 23% by weight of the hydrous crumb washed until washed in the same way as in Example 1, and it was confirmed that the Banbury workability index was about 36. . On the other hand, the hydrous crumb washed in the same manner as in Comparative Example 1 was dehydrated, dried and molded using a screw-type twin screw extrusion dryer under the same conditions as in Example 1. Gel amount of methyl ethyl ketone insoluble content of acrylic rubber veil is reduced to 3.4% by weight, and it is confirmed that the Banbury workability index is improved to about 24. That is, a method capable of reducing the gel amount of the methyl ethyl ketone insoluble component in the acrylic rubber veil or crumb-like acrylic rubber is a method of post-adding a chain transfer agent in the latter half of the emulsion polymerization of acrylic rubber, or a method of adding a hydrous crumb generated in the solidification step After washing, there is a method of extrusion drying by melt-kneading in a substantially water-free state (moisture content of less than 1% by weight) with a screw-type twin-screw extrusion dryer, but the latter method was overwhelmingly superior.

Regarding storage stability, it can be seen from Table 2-2 that the acrylic rubber veils (A) to (J) of the present invention, which have a large specific gravity and hardly contain air, have remarkably excellent storage stability. It can be seen that (Examples 1 to 10). In the present invention, in order not to mix air in the acrylic rubber veil, the air inherent in the acrylic rubber is removed under reduced pressure with the drying barrel part in the screw type twin screw extrusion dryer, and the acrylic rubber is dried in a state in which moisture is not substantially contained. After melt-kneading, it is rectified in the die part, and the resin pressure in the die part is limited, and the sheet-like dry rubber is extruded, and the cutting and lamination of the sheet-like dry rubber is made at a specific temperature, the specific gravity is increased, and the storage stability is remarkably improved. (Comparison of Examples 1 to 10 and Comparative Examples 1 to 2). In addition, the pH of the acrylic rubber veil of the present invention is in the specific range of 3 to 6, and this also contributes to storage stability (comparison of Examples 1 to 10 and Comparative Example 2).

Regarding water resistance, it can be seen from Table 2-2 that the acrylic rubber veils (A) to (J) of the present invention are remarkably excellent, and that the amount of ash in the acrylic rubber veil is greatly related (Example 1 ~10). The amount of ash in the acrylic rubber veil is determined by the type of emulsifier or coagulant, the coagulation method, the washing method, the dewatering method, etc. It can be seen that a significant reduction can be achieved by performing a coagulation reaction by adding an emulsification polymerization solution emulsified to the coagulation solution with vigorous stirring, washing with warm water, and dewatering and drying the hydrous crumb ( Comparison of Examples 1 to 10 and Comparative Examples 1 to 2). Here, the vigorously agitated coagulant liquid is a coagulation reaction by adding an emulsion polymerization liquid to the coagulant liquid stirred very vigorously at a circumferential speed of 1 m/s or more, and therefore, it is not shown in the examples of the present application. , Most of the hydrous crumb produced by the coagulation method performed in this example is concentrated in small particle diameters of 710 μm to 4.75 mm, and therefore, the washing efficiency with hot water and the ash removal efficiency by dehydration are remarkably improved. It is estimated that the water resistance of the acrylic rubber veil of the present invention could be improved.

From Table 2-2, the total amount of elements of phosphorus, magnesium, sodium, calcium and sulfur in the ash of the acrylic rubber veils (A) to (J) of the present invention and the acrylic rubbers (K) to (L) of the comparative examples were all 90 It can be seen that the weight % is exceeded, and the properties such as water resistance and mold release of the acrylic rubber veil are excellent. In particular, it can be seen that the water resistance is improved as the ratio of phosphorus and magnesium in the ash increases (Examples 1 to 10 and comparison in Comparative Example 1).

Regarding water resistance, it is also found from Table 2-1 and Table 2-2 that the amount of ash content and water resistance index in acrylic rubber differ depending on the type of emulsifier and coagulant (comparison between Comparative Example 1 and Comparative Example 2). . That is, the ash content with a large amount of sodium (Na) and sulfur (S) elements can be reduced to about 0.29% by weight (Comparative Example 2), but the ash content with a large amount of phosphorus (P) and magnesium (Mg) is higher than that in Comparative Example 2. It can be seen that only up to 1.39% by weight (Comparative Example 1) could be removed even after washing with warm water at 70°C, which has a high ash removal efficiency. In Examples 1 to 10 of the present application, the amount of ash was reduced using the ash content condition with a large amount of phosphorus (P) and magnesium (Mg), which are difficult to remove, and by the coagulation method, washing method, and dehydration method performed in the examples of the present application. It can be seen that the amount of ash in the acrylic rubber veil is drastically reduced and the water resistance can be improved (comparison between Examples 1 to 10 and Comparative Example 1). Although not shown in this example, when the polymerization reaction of Comparative Example 2 was carried out and the operation after the coagulation step was performed in the same way as in Example 1 to obtain an acrylic rubber veil, the ash content was reduced to about 0.08% by weight and the water resistance was also improved. I'm checking what I can.

Regarding water resistance, furthermore, from the comparison between Comparative Example 1 and Comparative Example 2, although the ash content of Comparative Example 1 with a large amount of phosphorus (P) and magnesium (Mg) is 4 times or more than that of Comparative Example 2, , it can be seen that the water resistance deteriorated only by about two times. In addition, although not shown in this Example, when the emulsion polymerization liquid of Comparative Example 1 was directly dried after the coagulation process and washing process were performed in the same way as in Example 1, the ash content (of the crumb-like acrylic rubber obtained) was 0.3 weight. It has been confirmed that it can be reduced to % and that the water resistance index at that time can be improved to about 40. That is, the water resistance of the crumb-like acrylic rubber having a large amount of phosphorus and magnesium in the ash content and the same amount of ash as that of Comparative Example 2 was improved by 60% by weight, and it was found that the water resistance was excellent when the phosphorus and magnesium content was higher. From Table 2-1 and Table 2-2, the total amount of phosphorus (P) and magnesium (Mg) in the ash with reduced ash content is 90% by weight or more, but this is the emulsifier used in the manufacturing process ( It can be seen that the phosphoric acid ester Na salt) and the coagulant (magnesium sulfate: MgSO ₄ ) do not remain in the acrylic rubber veil as they are, but remain after being salt-exchanged with poorly soluble phosphoric acid ester Mg during the coagulation reaction. . From the above, the reason why the water resistance of the acrylic rubber veil of the present invention is overwhelmingly excellent is estimated (Comparison of Examples 1 to 10 and Comparative Examples 1 to 2).

From Table 2-1 and Table 2-2, the acrylic rubber veils (A) to (J) of the present invention have crosslinkability, gel amount variation, Banbury processability, storage stability, water resistance, compression set resistance, It can be seen that the state physical properties including strength characteristics are excellent, and the roll processability is remarkably excellent (comparison between Examples 1 to 10 and Comparative Examples 1 to 2). From Table 2-2, it can be seen that the ratio (Mw/Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn), which is the molecular weight distribution in the low molecular weight region, is highly related to roll workability, and the higher the value, the better. (Comparison of Examples 1 to 10 and Comparative Examples 1 to 2). In addition, in order to achieve a high balance between strength characteristics and roll workability, it was found that it is important to increase the ratio (Mz/Mw) of the z-average molecular weight (Mz) and the weight-average molecular weight (Mw), which is the molecular weight distribution centering on the polymer component. there is.

From Table 2-1 and Table 2-2, acrylic rubber veils with highly balanced strength characteristics and roll processability were obtained by adding a slightly small amount of inorganic radical generating agent and adding a chain transfer agent (n-dodecylmercaptan) in batches. It can be seen that it can be prepared by post-adding to (Examples 1 to 10). This is because the inorganic radical generator is reduced to lengthen one polymer chain, and a chain transfer agent (n-dodecylmercaptan) is post-added batchwise to combine a high molecular weight component with a low molecular weight component, resulting in Mw/Mn or Mz/Mw It is speculated that the roll workability could be improved without impairing the strength characteristics by enlarging the molecular weight distribution of the etc. In addition, it can be seen that by drying the hydrous crumbs using a screw-type twin-screw extrusion dryer under conditions of high shear (maximum torque of 46 N m), the Mw/Mn is widened and the roll workability can be further improved (Example Comparison of 1-4 with Examples 5-10). On the other hand, although not shown in the data, even if the crumb-like acrylic rubbers (K) to (L) directly dried by hot air drying at 160 ° C. are dried with a screw-type twin-screw extrusion dryer under low shear conditions (maximum torque of 15 N m) It is confirmed that the molecular weight and molecular weight distribution hardly change. In addition, although not shown in Table 2-2, in the examples of the present application, sodium ascorbate as a reducing agent was added 120 minutes after the initiation of polymerization. This facilitates the production of high molecular weight components of acrylic rubber, resulting in strength characteristics and roll processability. characteristics are highly balanced.

As described above, from Table 2-1 and Table 2-2, it has at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom of the present invention, has a specific gravity of 0.9 or more, and an ash content of 0.15% by weight or less, Acrylic rubber veils (A) to ((A) where the gel amount is 30% by weight or less, and the value when the gel amount is randomly sampled at multiple points and the deviation is measured, and all of the above samplings measured within the range of the average value ± 5% by weight) J), it can be seen that the state physical properties, including both processability of roll and Banbury, storage stability, crosslinkability, water resistance, compression set resistance, and strength characteristics, are highly balanced, and all properties are highly excellent (Examples 1 to 3). 10).

With respect to the acrylic rubber composition comprising the acrylic rubber veils (A) to (J) of Examples 1 to 10, 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 2.0 minutes

○: Mooney scorch time t5 is 1.5 to 2.0 minutes

×: Mooney scorch time t5 is less than 1.5 minutes

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

[Releasability to mold]

The rubber compositions of the acrylic rubber veils (A) to (J) obtained in Examples 1 to 10 were press-fitted into a 10 mmφ × 200 mm mold, and the crosslinked rubber product after crosslinking at a mold temperature of 165 ° C. for 2 minutes was taken out, and the following When the mold releasability was evaluated as a standard, all of the acrylic rubber veils (A) to (J) 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 type extruder
6 cooling unit
7 Baling device

Claims (46)

It has at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group, and a chlorine atom, has a specific gravity of 0.9 or more, an ash content of 0.15% by weight or less, and a gel amount of 30% by weight or less, and the gel amount is arbitrarily sampled at multiple points and varied. An acrylic rubber veil in which all of the samplings measured within the range of (average value ± 5) weight% when the value is measured. According to claim 1,
Acrylic rubber veil with multi-point sampling of 20 points. According to claim 1 or 2,
An acrylic rubber veil whose gel amount is insoluble in methyl ethyl ketone. According to any one of claims 1 to 3,
An acrylic rubber veil in which the reactive group is an ionic reactive group. According to any one of claims 1 to 4,
An acrylic rubber veil with a weight average molecular weight (Mw) of absolute molecular weight measured by the GPC-MALS method in the range of 1,000,000 to 3,500,000. According to any one of claims 1 to 5,
An acrylic rubber veil with a number average molecular weight (Mn) of absolute molecular weight measured by the GPC-MALS method in the range of 100,000 to 500,000. According to any one of claims 1 to 6,
An acrylic rubber veil having a ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the absolute molecular weight distribution measured by the GPC-MALS method (Mw/Mn) of 3.5 or more. According to any one of claims 1 to 7,
An acrylic rubber veil in which the measurement solvent of the GPC-MALS method is a dimethylformamide solvent. According to any one of claims 1 to 8,
An acrylic rubber veil in which the total amount of sodium, magnesium, calcium, phosphorus and sulfur in the ash is 60% by weight or more. According to any one of claims 1 to 9,
Acrylic rubber veil with a specific gravity of 0.95 or higher. According to any one of claims 1 to 10,
Acrylic rubber veil with a pH of 6 or less. 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 polymer solution by using an alkali metal salt or a periodic table Group 2 metal salt 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 wherein 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. A step of emulsifying an acrylic rubber monomer component containing a monomer containing at least one reactive group selected from the group consisting of a carboxyl group, an epoxy group and a chlorine atom with water and an emulsifier;
An emulsion polymerization step of obtaining an emulsion polymerization solution by initiating a polymerization reaction and performing an emulsion polymerization reaction in the presence of a redox catalyst containing an inorganic radical generator and a reducing agent;
A coagulation step of adding the obtained emulsion polymerization liquid to a coagulating liquid stirred at a circumferential speed of 1 m/s or more and coagulating it to generate a hydrous crumb;
A cleaning step of washing the generated hydrous crumb with hot water;
A step of dewatering the washed hydrous crumb to a moisture content of 1 to 40% by weight in a dehydration barrel using a dehydration barrel having a dehydration slit, a drying barrel under reduced pressure, and a screw-type twin-screw extrusion dryer having a die at the tip;
A drying step of drying to less than 1% by weight in a drying barrel;
A molding step of extruding the sheet-shaped dry rubber from a die;
Lamination process in which extruded sheet-like dry rubber is laminated after cutting
Method for producing an acrylic rubber veil comprising a. According to claim 18,
A method for producing an acrylic rubber veil according to any one of claims 1 to 17. The method of claim 18 or 19,
A method for producing an acrylic rubber veil, wherein a chain transfer agent is batchwise post-added during polymerization in an emulsion polymerization process. The method of any one of claims 18 to 20,
A method for producing an acrylic rubber veil having a maximum torque of 25 N m or more of a screw type twin screw extrusion dryer. According to any one of claims 18 to 21,
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 18 to 22,
A method for producing an acrylic rubber veil in which a polymerization solution produced in an emulsion polymerization step is coagulated by using an alkali metal salt or a periodic table group 2 metal salt as a coagulant and dried. According to claim 23,
A method for producing an acrylic rubber veil in which a polymerization solution generated in an emulsion polymerization step is added to an aqueous solution containing a coagulant containing an alkali metal salt or a metal salt of Group 2 of the periodic table, and then solidified by stirring. The method of any one of claims 18 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, followed by melt kneading and drying. 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 25 to 27,
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. A rubber mixture comprising the acrylic rubber veil according to any one of claims 1 to 17, a filler and a crosslinking agent. According to claim 29,
A rubber mixture wherein the filler is a reinforcing filler. According to claim 29,
A rubber mixture wherein the filler is a carbon black. According to claim 29,
A rubber mixture wherein the filler is a silica type. The method of any one of claims 29 to 32,
A rubber mixture wherein the crosslinking agent is an organic crosslinking agent. The method of any one of claims 29 to 33,
A rubber mixture wherein the crosslinking agent is a polyvalent compound. The method of any one of claims 29 to 34,
A rubber mixture wherein the cross-linking agent is an ion-crosslinking compound. The method of claim 35,
A rubber mixture wherein the crosslinking agent is an ionic crosslinkable organic compound. The method of claim 35 or 36,
A rubber mixture wherein the crosslinking agent is a polyvalent ionic organic compound. The method of any one of claims 35 to 37,
A rubber mixture wherein the ion of the ion crosslinkable compound, ion crosslinkable organic compound or polyvalent ion 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. 38. The method of claim 37,
A rubber mixture wherein the crosslinking agent is 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. The method of any one of claims 29 to 39,
A rubber mixture 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 29 to 40,
A rubber mixture further comprising an anti-aging agent. The method of claim 41 ,
A rubber mixture wherein the anti-aging agent is an amine-based anti-aging agent. A method for producing a rubber mixture 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 17, a filler and, if necessary, an antiaging agent. A crosslinked rubber product formed by crosslinking the rubber mixture according to any one of claims 29 to 42. 45. The method of claim 44,
A rubber crosslinked product in which crosslinking of the rubber mixture is performed after molding. The method of claim 44 or 45,
A rubber crosslinked product in which crosslinking of the rubber mixture performs primary crosslinking and secondary crosslinking.

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