WO2020009185A1 - Production method for elastomer composition - Google Patents

Production method for elastomer composition Download PDF

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Publication number
WO2020009185A1
WO2020009185A1 PCT/JP2019/026621 JP2019026621W WO2020009185A1 WO 2020009185 A1 WO2020009185 A1 WO 2020009185A1 JP 2019026621 W JP2019026621 W JP 2019026621W WO 2020009185 A1 WO2020009185 A1 WO 2020009185A1
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Prior art keywords
elastomer
solvent
dispersion
mass
latex
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PCT/JP2019/026621
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French (fr)
Japanese (ja)
Inventor
徳之 三田尾
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日本ゼオン株式会社
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Priority to JP2020529046A priority Critical patent/JPWO2020009185A1/en
Publication of WO2020009185A1 publication Critical patent/WO2020009185A1/en

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/20—Compounding polymers with additives, e.g. colouring
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/02—Elements
    • C08K3/04—Carbon
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L21/00—Compositions of unspecified rubbers

Definitions

  • the present invention relates to a method for producing an elastomer composition.
  • Carbon nanotubes (hereinafter sometimes referred to as “CNT”) have excellent conductivity, thermal conductivity, sliding properties, mechanical properties, and the like. Therefore, in recent years, the development of a technique of adding a carbon nanotube to an elastomer to provide a material having excellent properties of the carbon nanotube and also having properties of the elastomer such as processability and strength has been promoted.
  • Patent Document 1 describes an elastomer composition containing 0.1 to 150 parts by weight of carbon nanotubes based on 100 parts by weight of an elastomer.
  • an elastomer composition is prepared by mixing a solution-based elastomer dissolved in a solvent and a dispersion in which carbon nanotubes are dispersed in a solvent.
  • the above-described elastomer composition has excellent workability, and also has an excellent balance between high heat generation and breaking strength when subjected to a vulcanization treatment.
  • an object of the present invention is to provide a method for efficiently producing an elastomer composition capable of supplying a molded article having excellent tear resistance.
  • the inventor has conducted intensive studies to achieve the above object.
  • the present inventor has proposed a latex containing an elastomer and a dispersion in which CNTs are dispersed in a solvent (organic solvent) having an SP value (solubility parameter) within a predetermined range and capable of dissolving the elastomer in the latex. It has been found that an elastomer composition exhibiting excellent tear resistance when formed into a molded article can be efficiently produced by mixing them under predetermined conditions, thereby completing the present invention.
  • an object of the present invention is to solve the above-described problem advantageously.
  • the method for producing an elastomer composition according to the present invention provides a latex containing an elastomer, a carbon nanotube and an SP value of 8.0 (cal). / Cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less and a dispersion containing a solvent capable of dissolving the elastomer with the dispersion with respect to the mass of the elastomer in the latex. It is characterized by including a mixing step of mixing so that the mass ratio of the solvent in the liquid becomes 4 or more.
  • the SP value is defined as the square root of the cohesive energy density, and is a parameter proposed by Hildebrand and Scott based on a regular solution in which the entropy change due to mixing is almost zero and the enthalpy change occurs.
  • Typical solvent solubility parameters are exemplified in the "Polymer Handbook" (Third Edition).
  • the phrase "the solvent is capable of dissolving the elastomer” means that when 0.5 g of the elastomer is dissolved in 100 g of the solvent at 25 ° C, the insoluble content is less than 1% by mass.
  • the elastomer is acrylonitrile-butadiene rubber, acrylonitrile-isoprene rubber, acrylonitrile-butadiene-isoprene rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, natural rubber, ethylene -At least one selected from the group consisting of propylene-diene rubber, butyl rubber, and hydrides thereof.
  • the carbon nanotube is a single-walled carbon nanotube.
  • the use of single-walled carbon nanotubes can further improve the tear resistance of a molded article of the obtained elastomer composition.
  • the solvent is at least one selected from the group consisting of acetone, methyl ethyl ketone, tetrahydrofuran, and toluene. If any of the above-mentioned solvents is used, a mixture in which the CNT and the elastomer are sufficiently well mixed is obtained, and as a result, the tear resistance of the molded article can be further improved.
  • the method for producing an elastomer composition of the present invention further includes a solid recovery step of recovering a solid from the mixture obtained in the mixing step.
  • a solid recovery step of recovering a solid from the mixture obtained in the mixing step.
  • an elastomer composition capable of supplying a molded article having excellent tear resistance can be efficiently produced.
  • the method for producing an elastomer composition of the present invention can be used when producing an elastomer composition (composite) composed of an elastomer and carbon nanotubes.
  • the elastomer composition produced by the method for producing an elastomer composition of the present invention can be formed into a molded product through, for example, a crosslinking treatment.
  • a dispersion containing a solvent capable of dissolving the elastomer, and a ratio of the mass of the solvent derived from the dispersion to the mass of the elastomer derived from the latex (hereinafter sometimes referred to as “solvent / elastomer ratio”). Is included to obtain at least 4 (mixing step).
  • a latex in which an elastomer is dispersed in water since a latex in which an elastomer is dispersed in water is used, the labor of dissolving a solid elastomer in a solvent can be omitted, and the production efficiency of the elastomer composition can be increased. Further, a latex containing an elastomer and a dispersion having CNTs dispersed in a solvent having an SP value within a predetermined range and capable of dissolving the elastomer are mixed so that the solvent / elastomer ratio becomes 4 or more.
  • the molded article formed from the elastomer composition obtained by using the production method of the present invention has excellent properties of CNT and excellent tear resistance, and thus is useful for production of various products.
  • a latex containing an elastomer and a dispersion containing a solvent whose CNT and SP values are within a predetermined range and capable of dissolving the elastomer are mixed so that the solvent / elastomer ratio becomes a predetermined value or more.
  • Latex a latex obtained by dispersing an elastomer in water is used.
  • the latex may contain components (other components) other than the elastomer and water.
  • the elastomer contained in the latex is not particularly limited, and a known elastomer can be used. Specifically, acrylonitrile-butadiene rubber (NBR), acrylonitrile-isoprene rubber, acrylonitrile-butadiene-isoprene rubber, styrene-butadiene rubber (SBR), butadiene rubber (BR), isoprene rubber (IR), natural rubber (NR) , Ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR), and hydrides thereof (hydrogenated acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-isoprene rubber, hydrogenated acrylonitrile-butadiene-isoprene rubber, hydrogenated styrene-butadiene) Rubber, hydrogenated butadiene rubber, hydrogenated isoprene rubber, hydrogenated natural rubber, hydrogenated ethylene-propylene-diene rubber,
  • These elastomers include those in which a hydrophilic group such as a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, and a hydroxyl group is introduced.
  • these elastomers may be used individually by 1 type, and may be used in combination of 2 or more types.
  • the concentration of the elastomer in the latex is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and preferably 10% by mass or more. Is particularly preferably 35% by mass or less, more preferably 30% by mass or less, still more preferably 25% by mass or less, and particularly preferably 20% by mass or less.
  • concentration of the elastomer in the latex is within the above range, the elastomer and the CNT can be sufficiently mixed in the obtained mixture, and as a result, various properties (such as tear resistance) of the molded article are further improved. be able to.
  • the other components contained in the latex are not particularly limited, and include, for example, a manufacturing aid (emulsifier, etc.) used for preparing a polymer elastomer.
  • the latex may contain a solvent (for example, a solvent having an SP value of 8.0 (cal / cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less).
  • the total ratio (concentration) of the other components contained in the latex is preferably 8% by mass or less, more preferably 4% by mass or less, even more preferably 2% by mass or less, It is particularly preferred that the content be 1% by mass or less.
  • the method for preparing the latex is not particularly limited.
  • one type or two or more types of monomers are polymerized in water and optionally hydrogenated, whereby a latex in which an elastomer as a polymer is dispersed in water can be obtained.
  • Known polymerization methods and hydrogenation methods can be used.
  • a natural product emulsion that is damaged by the bark of a rubber tree and flows out
  • the carbon nanotubes have a solvent as a dispersion medium, specifically having an SP value of 8.0 to 10.0 (cal / cm 3 ) 1/2 , and the elastomer in the latex described above is used.
  • a dispersion obtained by dispersing in a dissolvable solvent is used.
  • the dispersion may contain components (other components) other than the carbon nanotubes and the predetermined solvent.
  • the CNT is not particularly limited, and a single-walled carbon nanotube (single-walled CNT) and / or a multi-walled carbon nanotube (multi-walled CNT) can be used. Preferably, it is a single-walled CNT.
  • a molded article formed from the obtained elastomer composition can exhibit more excellent tear resistance as compared with a case where a multilayered CNT is used.
  • the average diameter of the CNTs is preferably 0.1 nm or more, more preferably 0.5 nm or more, still more preferably 1 nm or more, particularly preferably 3.5 nm or more, and 1000 nm. Is preferably not more than 100 nm, more preferably not more than 100 nm, further preferably not more than 50 nm, and particularly preferably not more than 10 nm. When the average diameter of the CNTs is within the above range, a molded article formed from the obtained elastomer composition can exhibit more excellent tear resistance.
  • the CNT a commercially available product may be used, or, for example, a raw material compound and a carrier gas are supplied onto a base material having a catalyst layer for CNT production on the surface thereof, and the chemical vapor deposition (CVD) method is performed.
  • CVD chemical vapor deposition
  • the concentration of CNT in the dispersion is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and still more preferably 0.1% by mass or more, It is still more preferably 0.2% by mass or more, particularly preferably 0.3% by mass or more, preferably 5% by mass or less, more preferably 3% by mass or less, and more preferably 2% by mass. %, More preferably at most 1% by mass.
  • concentration of CNT in the dispersion is within the above range, the elastomer and CNT can be sufficiently mixed in the obtained mixture, and as a result, various properties (such as tear resistance) of the molded article can be further improved. Can be done.
  • solvent As a solvent which is a dispersion medium of CNT, a solvent having an SP value of 8.0 (cal / cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less is used. If the SP value of the solvent is less than 8.0 (cal / cm 3 ) 1/2 , the water and the solvent are hardly compatible with each other when the latex and the dispersion are mixed, and the CNT and the elastomer are in a well-mixed state. No mixture can be obtained.
  • the SP value of the solvent is more than 10.0 (cal / cm 3 ) 1/2 , the elastomer is difficult to dissolve in the solvent when the latex and the dispersion are mixed, and as a result, each component and the solvent are mixed. It is presumed that the balance is lost, but aggregates (lumps) are generated, and a mixture in which CNTs and the elastomer are well mixed cannot be obtained. And even if it uses the mixture in which CNT and an elastomer are in a non-uniform mixing state, a desired elastomer composition cannot be manufactured efficiently.
  • a solvent having an SP value of 8 (cal / cm 3 ) 1/2 or more and 10 (cal / cm 3 ) 1/2 or less for example, acetone (SP value: 10.0), methyl ethyl ketone (SP value: 9.3), tetrahydrofuran (SP value: 9.4) and toluene (SP value: 8.8).
  • SP value: 10.0 acetone
  • SP value: 9.3 methyl ethyl ketone
  • SP value: 9.4 tetrahydrofuran
  • toluene SP value: 8.8
  • the solvent having an SP value of 8 (cal / cm 3 ) 1/2 or more and 10 (cal / cm 3 ) 1/2 or less may be used alone or in combination of two or more. Good.
  • a solvent having an SP value in the above-mentioned range preferably has a 1-octanol / water partition coefficient (log Pow) of 1.0 or less, more preferably 0.8 or less, and more preferably 0.8 or less. 5 or less, more preferably -2.0 or more, and even more preferably -1.0 or more.
  • a solvent having a 1-octanol / water partition coefficient in the above-described range a solid can be efficiently obtained by coagulation using an aqueous solvent in a solid obtaining step described later.
  • the “1-octanol / water partition coefficient” can be measured by a method based on JIS 7260-117: 2006.
  • the 1-octanol / water partition coefficient (log Pow) is 1.0 or less.
  • the solvent include acetone (log Pow: -0.24), methyl ethyl ketone (log Pow: 0.29), and tetrahydrofuran (log Pow: 0.46).
  • methyl ethyl ketone is particularly preferred as the solvent from the viewpoint of excellent handleability.
  • the dispersion liquid may be water or a solvent having an SP value outside the range of 8.0 to 10.0 (cal / cm 3 ) 1/2 (hereinafter, these are collectively referred to as “other dispersion medium”). ").
  • the proportion of the other dispersion medium contained in the dispersion is preferably 8% by mass or less, more preferably 4% by mass or less, still more preferably 2% by mass or less, and 1% by mass. % Is particularly preferred.
  • the dispersion may contain a dispersant.
  • the dispersant is not particularly limited as long as it assists the dispersion of the CNT, and examples thereof include a surfactant and a polysaccharide.
  • surfactant examples include sulfosuccinate-based anionic surfactant (product name: lipal (registered trademark; the same applies hereinafter) 835 l, manufactured by Lion Corporation), ripal 860K, ripal 870P, lipar MSC, lipar MSE, lipar NTD, Perox (registered trademark; the same applies hereinafter) TR, Perex TA, Perex OT-P manufactured by Kao Chemical Co., Ltd., an alkyl ether sulfonate sodium salt type anionic surfactant (Product name: Perex SS-L manufactured by Kao Chemical Co., Ltd.) Perex SS-H), sodium alkyl benzene sulfonate (product name: Libon LS-250, Libon PS-230, Libon PS260, Libon PS860, LN2050D, LN2450, BN2060 manufactured by Lion), sodium lauryl sulfate (product name: flower) Emal (registered trademark; the same applies
  • polysaccharides examples include gum arabic, sodium carboxymethylcellulose, ammonium carboxymethylcellulose, and hydroxyethylcellulose.
  • a dispersing agent may be used individually by 1 type, and may be used in combination of 2 or more types.
  • the dispersant can assist the dispersion of the CNT in the dispersion medium as described above.
  • the dispersant may precipitate (bleed) in the process of obtaining a molded article from the obtained elastomer composition.
  • the concentration of the dispersant contained in the dispersion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and 0.1% by mass or less. More preferably, it is particularly preferably 0.02% by mass or less, and most preferably 0% by mass.
  • the method for preparing the dispersion is not particularly limited. For example, by mixing the above-mentioned CNT and a solvent having an SP value within a predetermined range, and other optional components using a known mixer such as a bead mill, a dispersion in which CNTs are dispersed in a predetermined solvent. Can be prepared. Also, for example, after adding CNT and other optional components to a solvent having an SP value within a predetermined range, the obtained CNT-containing liquid is subjected to a dispersion treatment to disperse the CNT, whereby the CNT becomes A dispersion liquid dispersed in a predetermined solvent can be prepared.
  • the dispersion treatment for dispersing the CNTs in the CNT-containing liquid is not particularly limited, and a known dispersion treatment can be used.
  • a dispersing process capable of obtaining a cavitation effect or a crushing effect can be used.
  • the dispersion treatment for obtaining the cavitation effect is a dispersion method using a shock wave generated by bursting a vacuum bubble generated in a liquid when high energy is applied to the liquid.
  • Specific examples of the dispersion treatment that can achieve the cavitation effect include a dispersion treatment with an ultrasonic homogenizer, a dispersion treatment with a jet mill, and a dispersion treatment with a high-shear stirring device.
  • the dispersion treatment that provides a crushing effect is performed by applying a shearing force to the CNT-containing liquid to crush and disperse CNT aggregates, and further suppressing the generation of bubbles by applying a back pressure to the CNT-containing liquid. While dispersing the CNTs uniformly in the dispersion medium.
  • the dispersing process for obtaining the crushing effect can be performed by using a commercially available dispersing system (for example, a product name “BERYU SYSTEM PRO” (manufactured by Bigyu Corporation)).
  • the solvent / elastomer ratio needs to be 4 or more, preferably 10 or more, more preferably 20 or more, and 30 or more. More preferably, it is more preferably 32.8 or more. If the solvent / elastomer ratio is less than 4, the elastomer cannot be sufficiently dissolved in the solvent when the latex and the dispersion are mixed, and a mixture in which the CNT and the elastomer are well mixed cannot be obtained. And even if it uses the mixture in which CNT and an elastomer are in a non-uniform mixing state, a desired elastomer composition cannot be manufactured efficiently.
  • the upper limit of the solvent / elastomer ratio is not particularly limited, but is preferably 100 or less from the viewpoint of easily obtaining a solid in the solid recovery step described later.
  • the method of mixing the latex and the dispersion is not particularly limited, and for example, a known stirring method using a stirrer or the like can be employed.
  • the method for producing an elastomer composition of the present invention may include steps other than the mixing step described above.
  • the method for producing an elastomer composition of the present invention removes water and a solvent contained in the mixture from the mixture obtained in the above-described mixing step from the viewpoint of producing a desired elastomer composition sufficiently efficiently. It is preferable to include a step of collecting solids (solids collection step).
  • a method of recovering a solid containing at least an elastomer and CNTs from the mixture is not particularly limited.
  • a solid (especially elastomer) in the mixture is solidified to solidify as a solid.
  • a method in which the mixture is dried to remove water and a solvent to collect a solid as a dried product. From the viewpoint of efficiently collecting the solid, the former is preferable. That is, the method for producing an elastomer composition of the present invention preferably includes, as a solid recovery step, a step of recovering a solid by coagulation from the mixture obtained in the above-described mixing step (coagulation step).
  • the coagulation method is not particularly limited as long as the elastomer dissolved in the solvent can be coagulated, and a known coagulation method can be used.
  • a known coagulation method can be used.
  • the aqueous solvent include water and an organic solvent miscible with water (for example, isopropyl alcohol, methanol, and ethanol). Among these, water is preferred.
  • an aqueous solvent may be used individually by 1 type, and may be used in combination of 2 or more types.
  • the aqueous solvent may contain an acid such as sulfuric acid, acetic acid, formic acid, phosphoric acid, and hydrochloric acid, and a salt such as sodium chloride, aluminum sulfate, and potassium chloride.
  • the method for producing an elastomer composition of the present invention may further include, for example, after the above-mentioned solid matter collecting step, a step of washing the obtained solid matter with water (rinsing step), and a step of washing the solid matter after the water washing step
  • a drying step (drying step after washing with water) may be mentioned.
  • the method of washing the solid in the washing step is not particularly limited, and a known method can be employed.
  • known methods such as hot air drying and reduced pressure drying can be used as a method for drying the solid matter after washing with water.
  • the drying conditions can be appropriately set according to the use of the elastomer composition and the like.
  • a step of adding an additive according to the desired properties of a molded article formed from the elastomer composition to a solid material optionally subjected to the above-mentioned washing step or the like (Additive additive adding step).
  • the additives include a crosslinking agent, a crosslinking aid, a plasticizer, an antioxidant, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a pigment, a coloring agent, a foaming agent, an antistatic agent, and a hardener.
  • Examples include a fuel, a lubricant, a softener, a tackifier, a release agent, a deodorant, and a fragrance.
  • these additives may be used individually by 1 type, and may be used in combination of 2 or more types.
  • a crosslinking agent is not limited as long as it is used as a crosslinking agent for the elastomer.
  • Typical crosslinking agents include a sulfur-based crosslinking agent or an organic peroxide crosslinking agent that bridges between unsaturated bonds of the elastomer, and a sulfur-based crosslinking agent is preferred.
  • sulfur-based crosslinking agent examples include powdered sulfur, sulfur, precipitated sulfur, colloidal sulfur, sulfur such as surface-treated sulfur and insoluble sulfur; sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, dibenzothiazyl disulfide, Sulfur-containing compounds such as N, N'-dithio-bis (hexahydro-2H-azenopine-2), phosphorus-containing polysulfide and polymer polysulfide; tetramethylthiuram disulfide, selenium dimethyldithiocarbamate, 2- (4'-morpholino) Sulfur donating compounds such as dithio) benzothiazole.
  • sulfur chloride sulfur dichloride, morpholine disulfide, alkylphenol disulfide, dibenzothiazyl disulfide
  • Sulfur-containing compounds such as N, N'-dithio-bis (hexahydro-2H-azenopin
  • organic peroxide crosslinking agent examples include dicumyl peroxide, cumene hydroperoxide, t-butyl cumyl peroxide, paramenthane hydroperoxide, di-t-butyl peroxide, 1,3- and 1,4-bis (t -Butylperoxyisopropyl) benzene, 1,1-di-t-butylperoxy-3,3-trimethylcyclohexane, 4,4-bis- (t-butyl-peroxy) -n-butylvalerate, 2,5-dimethyl 2,5-di-t-butylperoxyhexane, 2,5-dimethyl-2,5-di-t-butylperoxyhexyne-3, 1,1-di-t-butylperoxy-3,5,5 -Trimethylcyclohexane, p-chlorobenzoyl peroxide, t-butylperoxyisopropyl carbonate, t-butyl
  • the amount of the crosslinking agent is not particularly limited, but is preferably 0.1 part by mass or more, more preferably 0.2 part by mass or more, and more preferably 10 parts by mass or less per 100 parts by mass of the elastomer. And more preferably 5 parts by mass or less.
  • a molded article having excellent tear resistance By molding the elastomer composition obtained by using the above-described method for producing an elastomer composition of the present invention, a molded article having excellent tear resistance can be obtained.
  • the molding method is not particularly limited, and a known method can be adopted.
  • crosslinking may be performed after molding, or crosslinking may be performed simultaneously with molding.
  • the crosslinking method is not particularly limited, and a known method can be employed.
  • the shape of the molded body can be an arbitrary shape such as a sheet shape depending on the use of the molded body.
  • ⁇ Mixed state of mixture> The mixture obtained in the mixing step was visually checked, and the mixing state was evaluated based on the following criteria.
  • B: Generation of aggregates (lumps) was confirmed by solidification of the elastomer and / or precipitation of CNTs. ⁇ Presence or absence of solid matter> It was visually confirmed whether a solid (coagulated product) was successfully precipitated by dropping the mixture into diluted sulfuric acid (pH 4).
  • Example 1 ⁇ Preparation of latex>
  • Example 2 A latex was prepared in the same manner as in Example 1 except that a dispersion was prepared as described below, and a mixing step, a solids collecting step, a washing step, a washing and drying step, and a molding A fabrication process was performed. Various evaluations were performed in the same manner as in Example 1. Table 1 shows the results.
  • MEK methyl ethyl ketone
  • ZONANO SG101 single-walled CNT, average diameter: 3.5 nm
  • dispersant linear chain
  • Example 1 A latex of acrylonitrile-butadiene rubber containing a carboxylic acid group was prepared in the same manner as in Example 1.
  • the CNT-containing liquid containing (sodium) was subjected to dispersion treatment using a jet mill to obtain a dispersion (CNT concentration: 0.3% by mass).
  • a latex containing an elastomer and a dispersion obtained by dispersing CNT in a solvent having an SP value within a predetermined range and capable of dissolving the elastomer in the latex have a solvent / elastomer ratio of a predetermined value.
  • Examples 1 and 2 in which a mixture was obtained by mixing as described above and a solid was recovered from the mixture an elastomer composition capable of forming a molded article having excellent tear resistance can be efficiently produced. I understand.
  • Comparative Example 1 using a dispersion obtained by dispersing CNTs in water, many dispersants were used to disperse the CNTs in water, and the amount of the dispersant remaining in the solid was excessive. It is guessed that the molded article had a reduced tear resistance.
  • Comparative Example 2 using a dispersion obtained by dispersing CNTs in water without using a dispersant, aggregates are generated as described above, and a mixture in which the elastomer and the CNTs are well mixed is obtained. I could't do that.
  • Comparative Example 3 in which methanol having an SP value outside the predetermined range was used as the solvent of the dispersion, aggregates were generated as described above, and a mixture in which the elastomer and CNT were well mixed could be obtained. could not. Then, a latex containing an elastomer and a dispersion obtained by dispersing CNTs in a solvent having an SP value within a predetermined range were mixed so that the solvent / elastomer ratio was less than a predetermined value to obtain a mixture. In Comparative Example 4, aggregates were generated as described above, and a mixture in which the elastomer and the CNT were mixed well could not be obtained.
  • an elastomer composition capable of supplying a molded article having excellent tear resistance can be efficiently produced.

Abstract

The purpose of the present invention is to provide a method for efficiently producing an elastomer composition capable of providing a molded body that exhibits excellent tear resistance. The elastomer composition production method according to the present invention comprises a mixing step for mixing a latex containing an elastomer with a dispersion liquid containing carbon nanotubes and a solvent that has an SP value of 8.0-10.0 (cal/cm3)1 / 2 and that is capable of dissolving the aforementioned elastomer, so that the mass ratio of the mass of the solvent in the dispersion liquid with respect to the mass of the elastomer in the latex is 4 or more.

Description

エラストマー組成物の製造方法Method for producing elastomer composition
　本発明は、エラストマー組成物の製造方法に関するものである。 The present invention relates to a method for producing an elastomer composition.
　カーボンナノチューブ（以下「ＣＮＴ」と称することがある。）は、導電性、熱伝導性、摺動特性、機械特性等に優れるため、幅広い用途への応用が検討されている。
　そこで、近年、エラストマーに対してカーボンナノチューブを添加することで、カーボンナノチューブの優れた特性を有すると共に、加工性や強度といったエラストマーの特性をも有する材料を提供する技術の開発が進められている。 BACKGROUND ART Carbon nanotubes (hereinafter sometimes referred to as “CNT”) have excellent conductivity, thermal conductivity, sliding properties, mechanical properties, and the like.
Therefore, in recent years, the development of a technique of adding a carbon nanotube to an elastomer to provide a material having excellent properties of the carbon nanotube and also having properties of the elastomer such as processability and strength has been promoted.
　例えば、特許文献１には、エラストマー１００重量部に対し、カーボンナノチューブを０．１～１５０重量部含有することを特徴とするエラストマー組成物が記載されている。ここで、特許文献１では、例えば、溶剤に溶解した溶液系のエラストマーと、カーボンナノチューブを溶剤に分散した分散液とを混合することによって、エラストマー組成物を調製している。そして特許文献１によれば、上述したエラストマー組成物は、加工性に優れると共に、加硫処理を施した際の高発熱性と破壊強度のバランスに優れる。 For example, Patent Document 1 describes an elastomer composition containing 0.1 to 150 parts by weight of carbon nanotubes based on 100 parts by weight of an elastomer. Here, in Patent Document 1, for example, an elastomer composition is prepared by mixing a solution-based elastomer dissolved in a solvent and a dispersion in which carbon nanotubes are dispersed in a solvent. According to Patent Literature 1, the above-described elastomer composition has excellent workability, and also has an excellent balance between high heat generation and breaking strength when subjected to a vulcanization treatment.
特開２００４－２１０８３０号公報JP 2004-210830 A
　しかしながら、上記従来の技術では、エラストマーを溶剤に溶解させる際に長時間を要する、また、得られたエラストマー組成物から形成される成形体の耐引裂き性に劣るといった問題があった。 However, in the above-mentioned conventional techniques, there are problems that it takes a long time to dissolve the elastomer in the solvent, and that a molded article formed from the obtained elastomer composition has poor tear resistance.
　そこで、本発明は、耐引裂き性に優れる成形体を供給可能なエラストマー組成物を、効率良く製造する方法を提供することを目的とする。 Therefore, an object of the present invention is to provide a method for efficiently producing an elastomer composition capable of supplying a molded article having excellent tear resistance.
　本発明者は、上記目的を達成するために鋭意検討を重ねた。そして、本発明者は、エラストマーを含むラテックスと、所定範囲内のＳＰ値（溶解度パラメータ）を有し且つラテックス中のエラストマーを溶解可能な溶剤（有機溶剤）中にＣＮＴが分散してなる分散液とを、所定の条件下で混合することで、成形体とした際に優れた耐引裂き性を奏するエラストマー組成物を効率良く製造し得ることを見出し、本発明を完成させた。 The inventor has conducted intensive studies to achieve the above object. The present inventor has proposed a latex containing an elastomer and a dispersion in which CNTs are dispersed in a solvent (organic solvent) having an SP value (solubility parameter) within a predetermined range and capable of dissolving the elastomer in the latex. It has been found that an elastomer composition exhibiting excellent tear resistance when formed into a molded article can be efficiently produced by mixing them under predetermined conditions, thereby completing the present invention.
　即ち、この発明は、上記課題を有利に解決することを目的とするものであり、本発明のエラストマー組成物の製造方法は、エラストマーを含むラテックスと、カーボンナノチューブおよびＳＰ値が８．０（ｃａｌ／ｃｍ３）１／２以上１０．０（ｃａｌ／ｃｍ３）１／２以下であって且つ前記エラストマーを溶解可能な溶剤を含む分散液とを、前記ラテックス中の前記エラストマーの質量に対する前記分散液中の前記溶剤の質量の比が４以上となるように混合する混合工程を含むことを特徴とする。上述の工程を経ることで、耐引裂き性に優れる成形体を供給可能なエラストマー組成物を、効率良く製造することができる。
　なお、本発明において、ＳＰ値は、凝集エネルギー密度の平方根と定義され、混合によるエントロピー変化がほとんどゼロで、エンタルピー変化が起こる正則な溶液をもとにＨｉｌｄｅｂｒａｎｄとＳｃｏｔｔにより提唱されたパラメータで、代表的な溶剤の溶解度パラメータは「ポリマーハンドブック」（第３版）に例示されている。
　また、本発明において、溶剤が「エラストマーを溶解可能」であるとは、２５℃において、１００ｇの溶剤にエラストマー０．５ｇを溶解した際に、不溶分が１質量％未満となることをいう。 That is, an object of the present invention is to solve the above-described problem advantageously. The method for producing an elastomer composition according to the present invention provides a latex containing an elastomer, a carbon nanotube and an SP value of 8.0 (cal). / Cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less and a dispersion containing a solvent capable of dissolving the elastomer with the dispersion with respect to the mass of the elastomer in the latex. It is characterized by including a mixing step of mixing so that the mass ratio of the solvent in the liquid becomes 4 or more. Through the above steps, an elastomer composition capable of supplying a molded article having excellent tear resistance can be efficiently produced.
In the present invention, the SP value is defined as the square root of the cohesive energy density, and is a parameter proposed by Hildebrand and Scott based on a regular solution in which the entropy change due to mixing is almost zero and the enthalpy change occurs. Typical solvent solubility parameters are exemplified in the "Polymer Handbook" (Third Edition).
In addition, in the present invention, the phrase "the solvent is capable of dissolving the elastomer" means that when 0.5 g of the elastomer is dissolved in 100 g of the solvent at 25 ° C, the insoluble content is less than 1% by mass.
　ここで、本発明のエラストマー組成物の製造方法では、前記エラストマーが、アクリロニトリル－ブタジエンゴム、アクリロニトリル－イソプレンゴム、アクリロニトリル－ブタジエン－イソプレンゴム、スチレン－ブタジエンゴム、ブタジエンゴム、イソプレンゴム、天然ゴム、エチレン－プロピレン－ジエンゴム、ブチルゴム、およびこれらの水素化物からなる群から選択される少なくとも１つとすることができる。 Here, in the method for producing an elastomer composition of the present invention, the elastomer is acrylonitrile-butadiene rubber, acrylonitrile-isoprene rubber, acrylonitrile-butadiene-isoprene rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, natural rubber, ethylene -At least one selected from the group consisting of propylene-diene rubber, butyl rubber, and hydrides thereof.
　そして、本発明のエラストマー組成物の製造方法では、前記カーボンナノチューブが、単層カーボンナノチューブであることが好ましい。単層カーボンナノチューブを用いれば、得られるエラストマー組成物の成形体の耐引裂き性を更に向上させることができる。 In the method for producing an elastomer composition of the present invention, it is preferable that the carbon nanotube is a single-walled carbon nanotube. The use of single-walled carbon nanotubes can further improve the tear resistance of a molded article of the obtained elastomer composition.
　また、本発明のエラストマー組成物の製造方法では、前記溶剤が、アセトン、メチルエチルケトン、テトラヒドロフラン、およびトルエンからなる群から選択される少なくとも１つであることが好ましい。上述した何れかの溶剤を用いれば、ＣＮＴとエラストマーが十分良好に混和した混合物を得て、結果として成形体の耐引裂き性を更に向上させることができる。 In the method for producing an elastomer composition of the present invention, it is preferable that the solvent is at least one selected from the group consisting of acetone, methyl ethyl ketone, tetrahydrofuran, and toluene. If any of the above-mentioned solvents is used, a mixture in which the CNT and the elastomer are sufficiently well mixed is obtained, and as a result, the tear resistance of the molded article can be further improved.
　そして、本発明のエラストマー組成物の製造方法は、前記混合工程で得られた混合物から、固形物を回収する固形物回収工程を更に含むことが好ましい。上述した固形物回収工程を経れば、所望のエラストマー組成物を十分に効率良く製造することができる。 Preferably, the method for producing an elastomer composition of the present invention further includes a solid recovery step of recovering a solid from the mixture obtained in the mixing step. Through the above-described solid recovery step, a desired elastomer composition can be produced sufficiently efficiently.
　本発明の製造方法によれば、耐引裂き性に優れる成形体を供給可能なエラストマー組成物を、効率良く製造することができる。 According to the production method of the present invention, an elastomer composition capable of supplying a molded article having excellent tear resistance can be efficiently produced.
　以下、本発明の実施形態について詳細に説明する。
　本発明のエラストマー組成物の製造方法は、エラストマーと、カーボンナノチューブが複合してなるエラストマー組成物（複合体）を製造する際に用いることができる。また、本発明のエラストマー組成物の製造方法を用いて製造したエラストマー組成物は、例えば架橋処理などを経て成形体とすることができる。 Hereinafter, embodiments of the present invention will be described in detail.
The method for producing an elastomer composition of the present invention can be used when producing an elastomer composition (composite) composed of an elastomer and carbon nanotubes. The elastomer composition produced by the method for producing an elastomer composition of the present invention can be formed into a molded product through, for example, a crosslinking treatment.
（エラストマー組成物の製造方法）
　本発明のエラストマー組成物の製造方法は、エラストマーを含むラテックスと、ＣＮＴおよびＳＰ値が８．０（ｃａｌ／ｃｍ３）１／２以上１０．０（ｃａｌ／ｃｍ３）１／２以下であって且つ上記エラストマーを溶解可能な溶剤を含む分散液とを、ラテックスに由来する上記エラストマーの質量に対する、分散液に由来する上記溶剤の質量の比（以下、「溶剤／エラストマー比」と称する場合がある。）が４以上となるように混合して混合物を得る工程（混合工程）を少なくとも含む。 (Method for producing elastomer composition)
In the method for producing an elastomer composition of the present invention, a latex containing an elastomer, a CNT and an SP value of 8.0 (cal / cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less. And a dispersion containing a solvent capable of dissolving the elastomer, and a ratio of the mass of the solvent derived from the dispersion to the mass of the elastomer derived from the latex (hereinafter sometimes referred to as “solvent / elastomer ratio”). Is included to obtain at least 4 (mixing step).
　上述した本発明の製造方法によれば、エラストマーが水中に分散してなるラテックスを用いるため、固形状のエラストマーを溶剤に溶解させるといった手間が省け、エラストマー組成物の製造効率を高めることができる。更に、エラストマーを含むラテックスと、所定範囲内のＳＰ値を有し且つエラストマーを溶解可能な溶剤中にＣＮＴが分散してなる分散液とを、溶剤／エラストマー比が４以上となるように混合することで、ＣＮＴとエラストマーが、水および溶剤中に均一に分散および／または溶解した混合物を得ることができるためと推察されるが、結果として耐引裂き性等の諸特性に優れる成形体を形成可能なエラストマー組成物が得られる。
　そして、本発明の製造方法を用いて得られるエラストマー組成物から形成される成形体は、ＣＮＴの優れた特性を備えると共に、耐引裂き性に優れるため、様々な製品の製造に有用である。 According to the above-described production method of the present invention, since a latex in which an elastomer is dispersed in water is used, the labor of dissolving a solid elastomer in a solvent can be omitted, and the production efficiency of the elastomer composition can be increased. Further, a latex containing an elastomer and a dispersion having CNTs dispersed in a solvent having an SP value within a predetermined range and capable of dissolving the elastomer are mixed so that the solvent / elastomer ratio becomes 4 or more. This is presumed to be because it is possible to obtain a mixture in which the CNT and the elastomer are uniformly dispersed and / or dissolved in water and a solvent. As a result, it is possible to form a molded article having excellent properties such as tear resistance. The resulting elastomer composition can be obtained.
The molded article formed from the elastomer composition obtained by using the production method of the present invention has excellent properties of CNT and excellent tear resistance, and thus is useful for production of various products.
＜混合工程＞
　混合工程では、エラストマーを含むラテックスと、ＣＮＴおよびＳＰ値が所定の範囲内であって且つ前記エラストマーを溶解可能な溶剤を含む分散液とを、溶剤／エラストマー比が所定の値以上となるように混合する。 <Mixing process>
In the mixing step, a latex containing an elastomer and a dispersion containing a solvent whose CNT and SP values are within a predetermined range and capable of dissolving the elastomer are mixed so that the solvent / elastomer ratio becomes a predetermined value or more. Mix.
＜＜ラテックス＞＞
　ラテックスとしては、エラストマーが水中に分散してなるラテックスを使用する。なお、ラテックスには、エラストマーと水以外の成分（その他の成分）が含まれていてもよい。 <<< Latex >>>
As the latex, a latex obtained by dispersing an elastomer in water is used. The latex may contain components (other components) other than the elastomer and water.
［エラストマー］
　ラテックスに含まれるエラストマーとしては、特に限定されず、既知のエラストマーを用いることができる。具体的には、アクリロニトリル－ブタジエンゴム（ＮＢＲ）、アクリロニトリル－イソプレンゴム、アクリロニトリル－ブタジエン－イソプレンゴム、スチレン－ブタジエンゴム（ＳＢＲ）、ブタジエンゴム（ＢＲ）、イソプレンゴム（ＩＲ）、天然ゴム（ＮＲ）、エチレン－プロピレン－ジエンゴム（ＥＰＤＭ）、ブチルゴム（ＩＩＲ）、そして、これらの水素化物（水素化アクリロニトリル－ブタジエンゴム、水素化アクリロニトリル－イソプレンゴム、水素化アクリロニトリル－ブタジエン－イソプレンゴム、水素化スチレン－ブタジエンゴム、水素化ブタジエンゴム、水素化イソプレンゴム、水素化天然ゴム、水素化エチレン－プロピレン－ジエンゴム、水素化ブチルゴム）が挙げられる。これら上述したエラストマーには、カルボン酸基、スルホン酸基、リン酸基、水酸基などの親水性基が導入されたものも含まれる。なお、これらのエラストマーは、１種類を単独で用いてもよく、２種類以上を組み合わせて用いてもよい。 [Elastomer]
The elastomer contained in the latex is not particularly limited, and a known elastomer can be used. Specifically, acrylonitrile-butadiene rubber (NBR), acrylonitrile-isoprene rubber, acrylonitrile-butadiene-isoprene rubber, styrene-butadiene rubber (SBR), butadiene rubber (BR), isoprene rubber (IR), natural rubber (NR) , Ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR), and hydrides thereof (hydrogenated acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-isoprene rubber, hydrogenated acrylonitrile-butadiene-isoprene rubber, hydrogenated styrene-butadiene) Rubber, hydrogenated butadiene rubber, hydrogenated isoprene rubber, hydrogenated natural rubber, hydrogenated ethylene-propylene-diene rubber, hydrogenated butyl rubber). These elastomers include those in which a hydrophilic group such as a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, and a hydroxyl group is introduced. In addition, these elastomers may be used individually by 1 type, and may be used in combination of 2 or more types.
　ここで、ラテックス中のエラストマーの濃度は、１質量％以上であることが好ましく、３質量％以上であることがより好ましく、５質量％以上であることが更に好ましく、１０質量％以上であることが特に好ましく、３５質量％以下であることが好ましく、３０質量％以下であることがより好ましく、２５質量％以下であることが更に好ましく、２０質量％以下であることが特に好ましい。ラテックス中のエラストマーの濃度が上述した範囲内であれば、得られる混合物中においてエラストマーとＣＮＴを十分良好に混和させることができ、結果として成形体の諸特性（耐引裂き性など）を更に向上させることができる。 Here, the concentration of the elastomer in the latex is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and preferably 10% by mass or more. Is particularly preferably 35% by mass or less, more preferably 30% by mass or less, still more preferably 25% by mass or less, and particularly preferably 20% by mass or less. When the concentration of the elastomer in the latex is within the above range, the elastomer and the CNT can be sufficiently mixed in the obtained mixture, and as a result, various properties (such as tear resistance) of the molded article are further improved. be able to.
［その他の成分］
　ラテックス中に含まれるその他の成分としては、特に限定されないが、例えば、重合体であるエラストマーの調製に用いた製造助剤（乳化剤など）が挙げられる。また、ラテックスは溶剤（例えば、ＳＰ値が８．０（ｃａｌ／ｃｍ３）１／２以上１０．０（ｃａｌ／ｃｍ３）１／２以下である溶剤）を含んでいてもよい。しかしながら、ラテックス中に含まれるその他の成分の合計割合（濃度）は、８質量％以下であることが好ましく、４質量％以下であることがより好ましく、２質量％以下であることが更に好ましく、１質量％以下であることが特に好ましい。 [Other ingredients]
The other components contained in the latex are not particularly limited, and include, for example, a manufacturing aid (emulsifier, etc.) used for preparing a polymer elastomer. Further, the latex may contain a solvent (for example, a solvent having an SP value of 8.0 (cal / cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less). However, the total ratio (concentration) of the other components contained in the latex is preferably 8% by mass or less, more preferably 4% by mass or less, even more preferably 2% by mass or less, It is particularly preferred that the content be 1% by mass or less.
［ラテックスの調製方法］
　ラテックスの調製方法は、特に限定されない。例えば、１種類または２種類以上の単量体を水中で重合し、任意に水素添加を行うことで、重合体であるエラストマーが水中に分散したラテックスを得ることができる。なお、重合の方法、水素添加の方法は、何れも既知のものを使用することができる。
　また、エラストマーとして天然ゴムを含むラテックスとしては、天然物（ゴム樹の樹皮を傷つけて流出する乳液）を用いることもできる。 [Method of preparing latex]
The method for preparing the latex is not particularly limited. For example, one type or two or more types of monomers are polymerized in water and optionally hydrogenated, whereby a latex in which an elastomer as a polymer is dispersed in water can be obtained. Known polymerization methods and hydrogenation methods can be used.
In addition, as the latex containing natural rubber as an elastomer, a natural product (emulsion that is damaged by the bark of a rubber tree and flows out) can also be used.
＜＜分散液＞＞
　分散液としては、カーボンナノチューブが、分散媒としての溶剤、具体的には８．０～１０．０（ｃａｌ／ｃｍ３）１／２のＳＰ値を有し、そして上述したラテックス中のエラストマーを溶解可能な溶剤中に分散してなる分散液を使用する。なお、分散液には、上記カーボンナノチューブと上記所定の溶剤以外の成分（その他の成分）が含まれていてもよい。 << Dispersion >>
As the dispersion, the carbon nanotubes have a solvent as a dispersion medium, specifically having an SP value of 8.0 to 10.0 (cal / cm 3 ) 1/2 , and the elastomer in the latex described above is used. A dispersion obtained by dispersing in a dissolvable solvent is used. The dispersion may contain components (other components) other than the carbon nanotubes and the predetermined solvent.
［カーボンナノチューブ］
　ＣＮＴとしては、特に限定されることなく、単層カーボンナノチューブ（単層ＣＮＴ）および／または多層カーボンナノチューブ（多層ＣＮＴ）を用いることができるが、ＣＮＴは、単層から５層までのカーボンナノチューブであることが好ましく、単層ＣＮＴであることがより好ましい。単層ＣＮＴを使用すれば、多層ＣＮＴを使用した場合と比較して、得られるエラストマー組成物から形成される成形体に、より優れた耐引裂き性を発揮させることができる。 [carbon nanotube]
The CNT is not particularly limited, and a single-walled carbon nanotube (single-walled CNT) and / or a multi-walled carbon nanotube (multi-walled CNT) can be used. Preferably, it is a single-walled CNT. When a single-walled CNT is used, a molded article formed from the obtained elastomer composition can exhibit more excellent tear resistance as compared with a case where a multilayered CNT is used.
　また、ＣＮＴの平均直径は、０．１ｎｍ以上であることが好ましく、０．５ｎｍ以上であることがより好ましく、１ｎｍ以上であることが更に好ましく、３．５ｎｍ以上であることが特に好ましく、１０００ｎｍ以下であることが好ましく、１００ｎｍ以下であることがより好ましく、５０ｎｍ以下であることが更に好ましく、１０ｎｍ以下であることが特に好ましい。ＣＮＴの平均直径が上述した範囲内であれば、得られるエラストマー組成物から形成される成形体に、より優れた耐引裂き性を発揮させることができる。 Further, the average diameter of the CNTs is preferably 0.1 nm or more, more preferably 0.5 nm or more, still more preferably 1 nm or more, particularly preferably 3.5 nm or more, and 1000 nm. Is preferably not more than 100 nm, more preferably not more than 100 nm, further preferably not more than 50 nm, and particularly preferably not more than 10 nm. When the average diameter of the CNTs is within the above range, a molded article formed from the obtained elastomer composition can exhibit more excellent tear resistance.
　そして、ＣＮＴとしては、市販品を用いてもよいし、例えば、ＣＮＴ製造用の触媒層を表面に有する基材上に、原料化合物およびキャリアガスを供給して、化学的気相成長法（ＣＶＤ法）によりＣＮＴを合成する際に、系内に微量の酸化剤（触媒賦活物質）を存在させることで、触媒層の触媒活性を飛躍的に向上させるという方法（スーパーグロース法；国際公開第２００６／０１１６５５号参照）で、効率的に製造してもよい。 As the CNT, a commercially available product may be used, or, for example, a raw material compound and a carrier gas are supplied onto a base material having a catalyst layer for CNT production on the surface thereof, and the chemical vapor deposition (CVD) method is performed. Method for synthesizing CNTs by a method (super-growth method; International Publication No. 2006), in which a small amount of an oxidizing agent (catalyst activating substance) is present in the system to dramatically improve the catalytic activity of the catalyst layer. / 011655) for efficient production.
　ここで、分散液中のＣＮＴの濃度は、０．０１質量％以上であることが好ましく、０．０５質量％以上であることがより好ましく、０．１質量％以上であることが更に好ましく、０．２質量％以上であることがより一層好ましく、０．３質量％以上であることが特に好ましく、５質量％以下であることが好ましく、３質量％以下であることがより好ましく、２質量％以下であることが更に好ましく、１質量％以下であることが特に好ましい。分散液中のＣＮＴの濃度が上述した範囲内であれば、得られる混合物中においてエラストマーとＣＮＴを十分良好に混和させることができ、結果として成形体の諸特性（耐引裂き性など）を更に向上させることができる。 Here, the concentration of CNT in the dispersion is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and still more preferably 0.1% by mass or more, It is still more preferably 0.2% by mass or more, particularly preferably 0.3% by mass or more, preferably 5% by mass or less, more preferably 3% by mass or less, and more preferably 2% by mass. %, More preferably at most 1% by mass. When the concentration of CNT in the dispersion is within the above range, the elastomer and CNT can be sufficiently mixed in the obtained mixture, and as a result, various properties (such as tear resistance) of the molded article can be further improved. Can be done.
［溶剤］
　ＣＮＴの分散媒である溶剤としては、ＳＰ値が８．０（ｃａｌ／ｃｍ３）１／２以上１０．０（ｃａｌ／ｃｍ３）１／２以下の溶剤を使用する。溶剤のＳＰ値が８．０（ｃａｌ／ｃｍ３）１／２未満であると、ラテックスと分散液を混合した際に水と溶剤が馴染み難く、ＣＮＴとエラストマーが良好に混和された状態にある混合物を得ることができない。一方、溶剤のＳＰ値が１０．０（ｃａｌ／ｃｍ３）１／２超であると、ラテックスと分散液を混合した際にエラストマーが溶剤に溶解し難く、その結果、各成分と溶媒とのバランスが崩れるものと推定されるが、凝集物（ダマ）が生じてしまい、ＣＮＴとエラストマーが良好に混和された状態にある混合物を得ることができない。そして、ＣＮＴとエラストマーが不均一な混和状態にある混合物を用いても、所望のエラストマー組成物を効率良く製造することはできない。 [solvent]
As a solvent which is a dispersion medium of CNT, a solvent having an SP value of 8.0 (cal / cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less is used. If the SP value of the solvent is less than 8.0 (cal / cm 3 ) 1/2 , the water and the solvent are hardly compatible with each other when the latex and the dispersion are mixed, and the CNT and the elastomer are in a well-mixed state. No mixture can be obtained. On the other hand, if the SP value of the solvent is more than 10.0 (cal / cm 3 ) 1/2 , the elastomer is difficult to dissolve in the solvent when the latex and the dispersion are mixed, and as a result, each component and the solvent are mixed. It is presumed that the balance is lost, but aggregates (lumps) are generated, and a mixture in which CNTs and the elastomer are well mixed cannot be obtained. And even if it uses the mixture in which CNT and an elastomer are in a non-uniform mixing state, a desired elastomer composition cannot be manufactured efficiently.
　ここで、ＳＰ値が８（ｃａｌ／ｃｍ３）１／２以上１０（ｃａｌ／ｃｍ３）１／２以下の溶剤としては、例えば、アセトン（ＳＰ値：１０．０）、メチルエチルケトン（ＳＰ値：９．３）、テトラヒドロフラン（ＳＰ値：９．４）およびトルエン（ＳＰ値：８．８）が挙げられる。これらの溶剤を用いることで、ＣＮＴとエラストマーが十分良好に混和した混合物を得て、結果として成形体の耐引裂き性を更に向上させることができる。なお、ＳＰ値が８（ｃａｌ／ｃｍ３）１／２以上１０（ｃａｌ／ｃｍ３）１／２以下の溶剤は、１種類を単独で用いてもよく、２種類以上を組み合わせて用いてもよい。 Here, as a solvent having an SP value of 8 (cal / cm 3 ) 1/2 or more and 10 (cal / cm 3 ) 1/2 or less, for example, acetone (SP value: 10.0), methyl ethyl ketone (SP value: 9.3), tetrahydrofuran (SP value: 9.4) and toluene (SP value: 8.8). By using these solvents, a mixture in which the CNT and the elastomer are sufficiently well mixed can be obtained, and as a result, the tear resistance of the molded article can be further improved. The solvent having an SP value of 8 (cal / cm 3 ) 1/2 or more and 10 (cal / cm 3 ) 1/2 or less may be used alone or in combination of two or more. Good.
　加えて、ＳＰ値が上述した範囲内である溶剤は、１－オクタノール／水分配係数（ｌｏｇ　Ｐｏｗ）が１．０以下であることが好ましく、０．８以下であることがより好ましく、０．５以下であることが更に好ましく、－２．０以上であることが好ましく、－１．０以上であることがより好ましい。１－オクタノール／水分配係数が上述の範囲内である溶剤を用いることで、後述する固形物の取得工程において、水性溶媒を用いた凝固によって、効率よく固形物を取得することが出来る。
　なお、本発明において、「１－オクタノール／水分配係数」は、ＪＩＳ　７２６０－１１７：２００６に準拠した方法で測定することができる。
　そして、上述したＳＰ値が８（ｃａｌ／ｃｍ３）１／２以上１０（ｃａｌ／ｃｍ３）１／２以下の溶剤の中でも、１－オクタノール／水分配係数（ｌｏｇ　Ｐｏｗ）が１．０以下である溶剤としては、アセトン（ｌｏｇ　Ｐｏｗ：－０．２４）、メチルエチルケトン（ｌｏｇ　Ｐｏｗ：０．２９）、テトラヒドロフラン（ｌｏｇ　Ｐｏｗ：０．４６）が挙げられる。 In addition, a solvent having an SP value in the above-mentioned range preferably has a 1-octanol / water partition coefficient (log Pow) of 1.0 or less, more preferably 0.8 or less, and more preferably 0.8 or less. 5 or less, more preferably -2.0 or more, and even more preferably -1.0 or more. By using a solvent having a 1-octanol / water partition coefficient in the above-described range, a solid can be efficiently obtained by coagulation using an aqueous solvent in a solid obtaining step described later.
In the present invention, the “1-octanol / water partition coefficient” can be measured by a method based on JIS 7260-117: 2006.
Among the solvents having an SP value of 8 (cal / cm 3 ) 1/2 or more and 10 (cal / cm 3 ) 1/2 or less, the 1-octanol / water partition coefficient (log Pow) is 1.0 or less. Examples of the solvent include acetone (log Pow: -0.24), methyl ethyl ketone (log Pow: 0.29), and tetrahydrofuran (log Pow: 0.46).
　そして、上述した中でも、溶剤としては、取り扱い性に優れる観点から、メチルエチルケトンが特に好ましい。 Among the above, methyl ethyl ketone is particularly preferred as the solvent from the viewpoint of excellent handleability.
［その他の成分］
　分散液中に含まれるその他の成分としては、特に限定されない。例えば、分散液は、分散媒として、水や、ＳＰ値が８．０～１０．０（ｃａｌ／ｃｍ３）１／２の範囲外である溶剤（以下、これらを纏めて「その他の分散媒」という。）を含んでいてもよい。しかしながら、分散液中に含まれるその他の分散媒の割合は、８質量％以下であることが好ましく、４質量％以下であることがより好ましく、２質量％以下であることが更に好ましく、１質量％以下であることが特に好ましい。 [Other ingredients]
Other components contained in the dispersion are not particularly limited. For example, the dispersion liquid may be water or a solvent having an SP value outside the range of 8.0 to 10.0 (cal / cm 3 ) 1/2 (hereinafter, these are collectively referred to as “other dispersion medium”). ").). However, the proportion of the other dispersion medium contained in the dispersion is preferably 8% by mass or less, more preferably 4% by mass or less, still more preferably 2% by mass or less, and 1% by mass. % Is particularly preferred.
　また例えば、分散液は、分散剤を含んでいてもよい。分散剤としては、ＣＮＴの分散を補助するものであれば特に限定されないが、界面活性剤や多糖類が挙げられる。 Also, for example, the dispersion may contain a dispersant. The dispersant is not particularly limited as long as it assists the dispersion of the CNT, and examples thereof include a surfactant and a polysaccharide.
　界面活性剤としては、例えば、スルホコハク酸塩系アニオン性界面活性剤（製品名：ライオン社製のリパール（登録商標；以下同じ）８３５ｌ、リパール８６０Ｋ、リパール８７０Ｐ、リパールＭＳＣ、リパールＭＳＥ、リパールＮＴＤ、花王ケミカル社製のペレックス（登録商標；以下同じ）ＴＲ、ペレックスＴＡ、ペレックスＯＴ－Ｐ）、アルキルエーテルスルホン酸ナトリウム塩系アニオン性界面活性剤（製品名：花王ケミカル社製のペレックスＳＳ－Ｌ、ペレックスＳＳ－Ｈ）、アルキルベンゼンスルホン酸ナトリウム塩（製品名：ライオン社製のライボンＬＳ－２５０、ライボンＰＳ－２３０、ライボンＰＳ２６０、ライボンＰＳ８６０、ＬＮ２０５０Ｄ、ＬＮ２４５０、ＢＮ２０６０）、ラウリル硫酸ナトリウム（製品名：花王ケミカル社製のエマール（登録商標；以下同じ）１０Ｇ、エマール１０ＰＴ、エマール２Ｆ－３０、エマール２ＦＧ、エマール２Ｆペースト、エマールＯ、エマールＯＳ、なお、ドデシル硫酸ナトリウムとしても市販されている）、アルキルベンゼンスルホン酸ナトリウム（製品名：花王ケミカル社製のネオペレックス（登録商標；以下同じ）Ｇ－１５、ネオペレックスＧ－２５、ネオペレックスＧ－６５）、１－ヘキサデカンスルホン酸ナトリウム、１－オクタデカンスルホン酸ナトリウム、１－ペンタデカンスルホン酸ナトリウム、１－テトラデカンスルホン酸ナトリウム、１－トリデカンスルホン酸ナトリウム、ラウリルアルコールエトキシレート（製品名：ＡＤＥＫＡ社製のアデカトール（登録商標；以下同じ）ＬＡ６７５Ｂ、アデカトールＬＡ７７５、アデカトール８７５、アデカトールＬＡ９７５、アデカトールＬＡ１２７５）、第２級アルコールエトキシレート（製品名：ＡＤＥＫＡ社製のアデカトールＳＯ－１０５、アデカトールＳＯ１２０、アデカトールＳＯ１３５、アデカトールＳＯ１４５）、特殊フェノールエトキシレート（製品名：ＡＤＥＫＡ社製のアデカトールＳＰ－１２、アデカトールＰＣ－１、アデカトールＰＣ－６、アデカトールＰＣ－１０）が挙げられる。 Examples of the surfactant include sulfosuccinate-based anionic surfactant (product name: lipal (registered trademark; the same applies hereinafter) 835 l, manufactured by Lion Corporation), ripal 860K, ripal 870P, lipar MSC, lipar MSE, lipar NTD, Perox (registered trademark; the same applies hereinafter) TR, Perex TA, Perex OT-P manufactured by Kao Chemical Co., Ltd., an alkyl ether sulfonate sodium salt type anionic surfactant (Product name: Perex SS-L manufactured by Kao Chemical Co., Ltd.) Perex SS-H), sodium alkyl benzene sulfonate (product name: Libon LS-250, Libon PS-230, Libon PS260, Libon PS860, LN2050D, LN2450, BN2060 manufactured by Lion), sodium lauryl sulfate (product name: flower) Emal (registered trademark; the same applies hereinafter) 10G, Emal 10PT, Emal 2F-30, Emal 2FG, Emal 2F paste, Emal O, Emal OS manufactured by Chemical Co., Ltd., also commercially available as sodium dodecyl sulfate), alkylbenzene sulfone Sodium (product name: Neoperex (registered trademark; the same applies hereinafter) G-15, Neoperex G-25, Neoperex G-65, manufactured by Kao Chemical Company), sodium 1-hexadecanesulfonate, sodium 1-octadecanesulfonate , Sodium 1-pentadecanesulfonate, sodium 1-tetradecanesulfonate, sodium 1-tridecanesulfonate, lauryl alcohol ethoxylate (product name: ADEKAOL (registered trademark; the same applies hereinafter) manufactured by ADEKA) LA675B, Kator LA775, Adecitol 875, Adecitol LA975, Adecitol LA1275), Secondary alcohol ethoxylate (Product name: Adekasol SO-105, Adekatrol SO120, Adekatole SO135, Adekasol SO145, manufactured by ADEKA), Special phenol ethoxylate (Product name: ADEKA SPADE-12, ADEKATOL PC-1, ADEKATOL PC-6, ADEKATOL PC-10) manufactured by ADEKA Corporation.
　多糖類としては、例えば、アラビアゴム、カルボキシメチルセルロースナトリウム塩、カルボキシメチルセルロースアンモニウム塩、ヒドロキシエチルセルロースが挙げられる。 Examples of polysaccharides include gum arabic, sodium carboxymethylcellulose, ammonium carboxymethylcellulose, and hydroxyethylcellulose.
　なお、分散剤は、１種類を単独で用いてもよく、２種類以上を組み合わせて用いてもよい。
　ここで、分散剤は、上記の通りＣＮＴの分散媒中での分散を補助しうる。しかしながら、分散剤は、得られるエラストマー組成物から成形体を得る過程において析出（ブリード）してしまう場合がある。更には、本発明者らの検討によれば、エラストマー組成物中に分散剤が残存することで、成形体の耐引裂き性が低下することが明らかとなった。このような観点からは、分散液中に含まれる分散剤の濃度は、１質量％以下であることが好ましく、０．５質量％以下であることがより好ましく、０．１質量％以下であることが更に好ましく、０．０２質量％以下であることが特に好ましく、０質量％であることが最も好ましい。 In addition, a dispersing agent may be used individually by 1 type, and may be used in combination of 2 or more types.
Here, the dispersant can assist the dispersion of the CNT in the dispersion medium as described above. However, the dispersant may precipitate (bleed) in the process of obtaining a molded article from the obtained elastomer composition. Furthermore, according to the study of the present inventors, it has been clarified that the tear resistance of the molded article is reduced by the dispersant remaining in the elastomer composition. From such a viewpoint, the concentration of the dispersant contained in the dispersion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and 0.1% by mass or less. More preferably, it is particularly preferably 0.02% by mass or less, and most preferably 0% by mass.
［分散液の調製方法］
　分散液の調製方法は、特に限定されない。例えば、上述したＣＮＴおよび所定範囲内のＳＰ値を有する溶剤、並びに任意使用のその他の成分をビーズミルなどの既知の混合機を用いて混合することで、ＣＮＴが所定の溶剤中に分散した分散液を調製することができる。
　また例えば、所定範囲内のＳＰ値を有する溶剤に対して、ＣＮＴおよび任意使用のその他の成分を添加した後、得られたＣＮＴ含有液に分散処理を施してＣＮＴを分散させることにより、ＣＮＴが所定の溶剤中に分散した分散液を調製することができる。
　ここで、ＣＮＴ含有液中のＣＮＴを分散させる際の分散処理としては、特に限定されることなく、既知の分散処理を用いることができる。具体的には、分散処理としては、キャビテーション効果または解砕効果が得られる分散処理を用いることができる。なお、キャビテーション効果が得られる分散処理は、液体に高エネルギーを付与した際、液中に生じた真空の気泡が破裂することにより生じる衝撃波を利用した分散方法である。そして、キャビテーション効果が得られる分散処理の具体例としては、超音波ホモジナイザーによる分散処理、ジェットミルによる分散処理および高剪断撹拌装置による分散処理が挙げられる。また、解砕効果が得られる分散処理は、ＣＮＴ含有液にせん断力を与えてＣＮＴの凝集体を解砕・分散させ、さらにＣＮＴ含有液に背圧を負荷することで、気泡の発生を抑制しつつ、ＣＮＴを分散媒中に均一に分散させる分散方法である。そして、解砕効果が得られる分散処理は、市販の分散システム（例えば、製品名「ＢＥＲＹＵ  ＳＹＳＴＥＭ  ＰＲＯ」（株式会社美粒製）など）を用いて行うことができる。 [Method of preparing dispersion]
The method for preparing the dispersion is not particularly limited. For example, by mixing the above-mentioned CNT and a solvent having an SP value within a predetermined range, and other optional components using a known mixer such as a bead mill, a dispersion in which CNTs are dispersed in a predetermined solvent. Can be prepared.
Also, for example, after adding CNT and other optional components to a solvent having an SP value within a predetermined range, the obtained CNT-containing liquid is subjected to a dispersion treatment to disperse the CNT, whereby the CNT becomes A dispersion liquid dispersed in a predetermined solvent can be prepared.
Here, the dispersion treatment for dispersing the CNTs in the CNT-containing liquid is not particularly limited, and a known dispersion treatment can be used. Specifically, as the dispersing process, a dispersing process capable of obtaining a cavitation effect or a crushing effect can be used. Note that the dispersion treatment for obtaining the cavitation effect is a dispersion method using a shock wave generated by bursting a vacuum bubble generated in a liquid when high energy is applied to the liquid. Specific examples of the dispersion treatment that can achieve the cavitation effect include a dispersion treatment with an ultrasonic homogenizer, a dispersion treatment with a jet mill, and a dispersion treatment with a high-shear stirring device. In addition, the dispersion treatment that provides a crushing effect is performed by applying a shearing force to the CNT-containing liquid to crush and disperse CNT aggregates, and further suppressing the generation of bubbles by applying a back pressure to the CNT-containing liquid. While dispersing the CNTs uniformly in the dispersion medium. The dispersing process for obtaining the crushing effect can be performed by using a commercially available dispersing system (for example, a product name “BERYU SYSTEM PRO” (manufactured by Bigyu Corporation)).
＜＜ラテックスと分散液の混合＞＞
　上記ラテックスと上記分散液を混合して混合物を調製するに際し、溶剤／エラストマー比が、４以上であることが必要であり、１０以上であることが好ましく、２０以上であることがより好ましく、３０以上であることが更に好ましく、３２．８以上であることが特に好ましい。溶剤／エラストマー比が４未満であると、ラテックスと分散液を混合した際にエラストマーを溶剤に十分に溶解させることができず、ＣＮＴとエラストマーが良好に混和された混合物を得ることができない。そして、ＣＮＴとエラストマーが不均一な混和状態にある混合物を用いても、所望のエラストマー組成物を効率良く製造することはできない。一方、溶剤／エラストマー比の上限は、特に限定されないが、後述する固形物回収工程において固形物を容易に得る観点からは１００以下が好ましい。 << Mixing of latex and dispersion >>
When the latex and the dispersion are mixed to prepare a mixture, the solvent / elastomer ratio needs to be 4 or more, preferably 10 or more, more preferably 20 or more, and 30 or more. More preferably, it is more preferably 32.8 or more. If the solvent / elastomer ratio is less than 4, the elastomer cannot be sufficiently dissolved in the solvent when the latex and the dispersion are mixed, and a mixture in which the CNT and the elastomer are well mixed cannot be obtained. And even if it uses the mixture in which CNT and an elastomer are in a non-uniform mixing state, a desired elastomer composition cannot be manufactured efficiently. On the other hand, the upper limit of the solvent / elastomer ratio is not particularly limited, but is preferably 100 or less from the viewpoint of easily obtaining a solid in the solid recovery step described later.
　なお、ラテックスと分散液を混合する方法は特に限定されず、例えば、スターラー等を用いた既知の攪拌方法を採用することができる。 The method of mixing the latex and the dispersion is not particularly limited, and for example, a known stirring method using a stirrer or the like can be employed.
＜その他の工程＞
　本発明のエラストマー組成物の製造方法は、上述した混合工程以外の工程を含んでいてもよい。例えば、本発明のエラストマー組成物の製造方法は、所望のエラストマー組成物を十分に効率良く製造する観点から、上述した混合工程で得られた混合物から、混合物に含まれる水および溶剤を除去して、固形物を回収する工程（固形物回収工程）を含むことが好ましい。 <Other steps>
The method for producing an elastomer composition of the present invention may include steps other than the mixing step described above. For example, the method for producing an elastomer composition of the present invention removes water and a solvent contained in the mixture from the mixture obtained in the above-described mixing step from the viewpoint of producing a desired elastomer composition sufficiently efficiently. It is preferable to include a step of collecting solids (solids collection step).
　固形物回収工程において、混合物から、少なくともエラストマーおよびＣＮＴを含む固形物を回収する方法は、特に限定されないが、例えば、混合物中の固形分（特にはエラストマー）を凝固させることで凝固物として固形物を回収する方法、混合物を乾燥して水および溶剤を除去することで乾燥物として固形物を回収する方法、が挙げられるが、効率よく固形物を回収する観点から、前者が好ましい。すなわち、本発明のエラストマー組成物の製造方法は、固形物回収工程として、上述した混合工程で得られた混合物から、凝固により固形物を回収する工程（凝固工程）を含むことが好ましい。
　凝固方法としては、溶剤中に溶解したエラストマーを凝固させることができれば特に限定されず、既知の凝固方法を用いることができる。例えば、混合工程で得られた混合物を多量の水性溶媒に少量ずつ滴下することで、混合物中の固形分を凝固させて固形物を析出させることができる。
　ここで、水性溶媒としては、水や、水と混和可能な有機溶媒（例えば、イソプロピルアルコール、メタノール、エタノール）が挙げられる。これらの中でも、水が好ましい。なお、水性溶媒は、１種類を単独で用いてもよく、２種類以上を組み合わせて用いてもよい。また、水性溶媒は、硫酸、酢酸、蟻酸、リン酸、塩酸などの酸や、塩化ナトリウム、硫酸アルミニウム、塩化カリウム等の塩を含んでいてもよい。 In the solid recovery step, a method of recovering a solid containing at least an elastomer and CNTs from the mixture is not particularly limited. For example, a solid (especially elastomer) in the mixture is solidified to solidify as a solid. And a method in which the mixture is dried to remove water and a solvent to collect a solid as a dried product. From the viewpoint of efficiently collecting the solid, the former is preferable. That is, the method for producing an elastomer composition of the present invention preferably includes, as a solid recovery step, a step of recovering a solid by coagulation from the mixture obtained in the above-described mixing step (coagulation step).
The coagulation method is not particularly limited as long as the elastomer dissolved in the solvent can be coagulated, and a known coagulation method can be used. For example, by dropping the mixture obtained in the mixing step into a large amount of an aqueous solvent little by little, solids in the mixture can be solidified to precipitate solids.
Here, examples of the aqueous solvent include water and an organic solvent miscible with water (for example, isopropyl alcohol, methanol, and ethanol). Among these, water is preferred. In addition, an aqueous solvent may be used individually by 1 type, and may be used in combination of 2 or more types. Further, the aqueous solvent may contain an acid such as sulfuric acid, acetic acid, formic acid, phosphoric acid, and hydrochloric acid, and a salt such as sodium chloride, aluminum sulfate, and potassium chloride.
　本発明のエラストマー組成物の製造方法が、更に含み得る工程としては、例えば、上述した固形物回収工程の後、得られた固形物を水洗する工程（水洗工程）、水洗工程後の固形物を乾燥する工程（水洗後乾燥工程）が挙げられる。
　水洗工程において固形物を水洗する方法は、特に限定されず既知の方法を採用することができる。また、水洗後乾燥工程において、水洗を行った後の固形物を乾燥する方法としては、温風乾燥、減圧乾燥などの既知の方法を採用することができる。また、乾燥条件は、エラストマー組成物の用途などに応じて適宜設定することができる。 As a step that the method for producing an elastomer composition of the present invention may further include, for example, after the above-mentioned solid matter collecting step, a step of washing the obtained solid matter with water (rinsing step), and a step of washing the solid matter after the water washing step A drying step (drying step after washing with water) may be mentioned.
The method of washing the solid in the washing step is not particularly limited, and a known method can be employed. In the drying step after washing with water, known methods such as hot air drying and reduced pressure drying can be used as a method for drying the solid matter after washing with water. The drying conditions can be appropriately set according to the use of the elastomer composition and the like.
　更に、本発明のエラストマー組成物の製造方法は、任意に上記水洗工程等を経た固形物に対し、エラストマー組成物から形成される成形体の所望の性状などに応じた添加剤を添加する工程（添加剤添加工程）を含んでいてもよい。
　添加剤としては、例えば、架橋剤、架橋助剤、可塑剤、老化防止剤、酸化防止剤、熱安定剤、光安定剤、紫外線吸収剤、顔料、着色剤、発泡剤、帯電防止剤、難燃剤、滑剤、軟化剤、粘着付与剤、離型剤、防臭剤、香料が挙げられる。なお、これらの添加剤は、１種類を単独で用いてもよく、２種類以上を組み合わせて用いてもよい。そしてこれらの中でも、添加剤としては、エラストマー組成物の成形性向上、およびエラストマー組成物から形成される成形体の機械的強度確保などのため、架橋剤を用いることが好ましい。架橋剤としてはエラストマーの架橋剤として使用されるものであれば限定されない。代表的な架橋剤としては、エラストマーの不飽和結合間を架橋する硫黄系架橋剤または有機過酸化物架橋剤が挙げられ、硫黄系架橋剤が好ましい。 Further, in the method for producing an elastomer composition of the present invention, a step of adding an additive according to the desired properties of a molded article formed from the elastomer composition to a solid material optionally subjected to the above-mentioned washing step or the like ( (Additive additive adding step).
Examples of the additives include a crosslinking agent, a crosslinking aid, a plasticizer, an antioxidant, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a pigment, a coloring agent, a foaming agent, an antistatic agent, and a hardener. Examples include a fuel, a lubricant, a softener, a tackifier, a release agent, a deodorant, and a fragrance. In addition, these additives may be used individually by 1 type, and may be used in combination of 2 or more types. Among these, it is preferable to use a crosslinking agent as an additive in order to improve the moldability of the elastomer composition and secure the mechanical strength of a molded article formed from the elastomer composition. The crosslinking agent is not limited as long as it is used as a crosslinking agent for the elastomer. Typical crosslinking agents include a sulfur-based crosslinking agent or an organic peroxide crosslinking agent that bridges between unsaturated bonds of the elastomer, and a sulfur-based crosslinking agent is preferred.
　硫黄系架橋剤としては、例えば、粉末硫黄、硫黄華、沈降性硫黄、コロイド硫黄、表面処理硫黄及び不溶性硫黄などの硫黄；塩化硫黄、二塩化硫黄、モルホリンジスルフィド、アルキルフェノールジスルフィド、ジベンゾチアジルジスルフィド、Ｎ，Ｎ’－ジチオ－ビス（ヘキサヒドロ－２Ｈ－アゼノピン－２）、含リンポリスルフィド及び高分子多硫化物などの含硫黄化合物；テトラメチルチウラムジスルフィド、ジメチルジチオカルバミン酸セレン、２－（４’－モルホリノジチオ）ベンゾチアゾールなどの硫黄供与性化合物が挙げられる。 Examples of the sulfur-based crosslinking agent include powdered sulfur, sulfur, precipitated sulfur, colloidal sulfur, sulfur such as surface-treated sulfur and insoluble sulfur; sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, dibenzothiazyl disulfide, Sulfur-containing compounds such as N, N'-dithio-bis (hexahydro-2H-azenopine-2), phosphorus-containing polysulfide and polymer polysulfide; tetramethylthiuram disulfide, selenium dimethyldithiocarbamate, 2- (4'-morpholino) Sulfur donating compounds such as dithio) benzothiazole.
　有機過酸化物架橋剤としては、例えば、ジクミルペルオキシド、クメンヒドロペルオキシド、ｔ－ブチルクミルペルオキシド、パラメンタンヒドロペルオキシド、ジ－ｔ－ブチルペルオキシド、１，３－及び１，４－ビス（ｔ－ブチルペルオキシイソプロピル）ベンゼン、１，１－ジ－ｔ－ブチルペルオキシ－３，３－トリメチルシクロヘキサン、４，４－ビス－（ｔ－ブチル－ペルオキシ）－ｎ－ブチルバレレート、２，５－ジメチル－２，５－ジ－ｔ－ブチルペルオキシヘキサン、２，５－ジメチル－２，５－ジ－ｔ－ブチルペルオキシヘキシン－３、１，１－ジ－ｔ－ブチルペルオキシ－３，５，５－トリメチルシクロヘキサン、ｐ－クロロベンゾイルペルオキシド、ｔ－ブチルペルオキシイソプロピルカーボネート、ｔ－ブチルペルオキシベンゾエートが挙げられる。 Examples of the organic peroxide crosslinking agent include dicumyl peroxide, cumene hydroperoxide, t-butyl cumyl peroxide, paramenthane hydroperoxide, di-t-butyl peroxide, 1,3- and 1,4-bis (t -Butylperoxyisopropyl) benzene, 1,1-di-t-butylperoxy-3,3-trimethylcyclohexane, 4,4-bis- (t-butyl-peroxy) -n-butylvalerate, 2,5-dimethyl 2,5-di-t-butylperoxyhexane, 2,5-dimethyl-2,5-di-t-butylperoxyhexyne-3, 1,1-di-t-butylperoxy-3,5,5 -Trimethylcyclohexane, p-chlorobenzoyl peroxide, t-butylperoxyisopropyl carbonate, t-butylpe Oxy benzoate.
　なお、架橋剤の添加量は特に限定されないが、エラストマー１００質量部当たり、０．１質量部以上であることが好ましく、０．２質量部以上であることがより好ましく、１０質量部以下であることが好ましく、５質量部以下であることがより好ましい。 The amount of the crosslinking agent is not particularly limited, but is preferably 0.1 part by mass or more, more preferably 0.2 part by mass or more, and more preferably 10 parts by mass or less per 100 parts by mass of the elastomer. And more preferably 5 parts by mass or less.
（成形体）
　上述した本発明のエラストマー組成物の製造方法を用いて得られるエラストマー組成物を成形することで、耐引裂き性に優れる成形体を得ることができる。成形方法は、特に限定されず既知の方法を採用することができる。なお成形体を得るに際し、エラストマー組成物が架橋剤を含む場合は、成形した後に架橋しても、成形と同時に架橋を行ってもよい。架橋方法については、特に限定されず既知の方法を採用することができる。また、成形体の形状は、シート状など成形体の用途に応じた任意の形状とすることができる。 (Molded body)
By molding the elastomer composition obtained by using the above-described method for producing an elastomer composition of the present invention, a molded article having excellent tear resistance can be obtained. The molding method is not particularly limited, and a known method can be adopted. When a molded article is obtained, when the elastomer composition contains a crosslinking agent, crosslinking may be performed after molding, or crosslinking may be performed simultaneously with molding. The crosslinking method is not particularly limited, and a known method can be employed. Further, the shape of the molded body can be an arbitrary shape such as a sheet shape depending on the use of the molded body.
　以下、本発明について実施例に基づき具体的に説明するが、本発明はこれら実施例に限定されるものではない。
　実施例および比較例において、混合工程で得られる混合物の混和状態、固形物回収工程における固形物の析出の有無、固形物中の分散剤量、および成形体の耐引裂き性は、以下の方法を使用して評価した。 Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.
In Examples and Comparative Examples, the mixing state of the mixture obtained in the mixing step, the presence or absence of precipitation of solids in the solids recovery step, the amount of dispersant in the solids, and the tear resistance of the molded article, the following method Used and evaluated.
＜混合物の混和状態＞
　混合工程で得られた混合物を目視で確認し、下記の基準で混和状態を評価した。
　Ａ：エラストマーおよびＣＮＴが均一に混和した状態である。
　Ｂ：エラストマーの凝固および／またはＣＮＴの析出により、凝集物（ダマ）の発生が確認された。
＜固形物の析出有無＞
　混合物を、希硫酸（ｐＨ＝４）に滴下することにより固形物（凝固物）を良好に析出できたかを、目視により確認した。
　Ａ：混合物を希硫酸（ｐＨ＝４）に滴下することで、固形物（凝固物）を析出させることができた。
　Ｂ：混合物を希硫酸（ｐＨ＝４）へ滴下しても、固形物（凝固物）を析出させることができなかった。
＜固形物中の分散剤量＞
　水洗工程および水洗後乾燥工程後に得られたＣＮＴとエラストマーの複合体から分散剤成分を抽出し、液体クロマトグラフィーで定量した。
＜成形体の耐引裂き性＞
　得られたシート状の成形体から、ＪＩＳ　Ｋ６２５２に従い、切込みなしアングル形の打ち抜き刃で打ち抜くことで試験片を得て、列理方向に引裂き試験を行い、引裂き強度を測定した。引裂き強度の値が高いほど、成形体が耐引裂き性に優れることを示す。 <Mixed state of mixture>
The mixture obtained in the mixing step was visually checked, and the mixing state was evaluated based on the following criteria.
A: A state in which the elastomer and the CNT are uniformly mixed.
B: Generation of aggregates (lumps) was confirmed by solidification of the elastomer and / or precipitation of CNTs.
<Presence or absence of solid matter>
It was visually confirmed whether a solid (coagulated product) was successfully precipitated by dropping the mixture into diluted sulfuric acid (pH = 4).
A: A solid (coagulated product) could be precipitated by dropping the mixture into diluted sulfuric acid (pH = 4).
B: Even when the mixture was dropped into dilute sulfuric acid (pH = 4), a solid (coagulated product) could not be precipitated.
<Amount of dispersant in solid material>
The dispersant component was extracted from the composite of CNT and elastomer obtained after the water washing step and the water washing and drying step, and quantified by liquid chromatography.
<Tear resistance of molded product>
According to JIS K6252, a test piece was obtained from the obtained sheet-like molded body by punching with an angle-shaped punching blade, and a tear test was performed in the grain direction to measure the tear strength. The higher the value of the tear strength, the more excellent the molded body is in the tear resistance.
（実施例１）
＜ラテックスの準備＞
　金属製ボトル中に、イオン交換水６２９質量部、ドデシルベンゼンスルホン酸ナトリウム水溶液（濃度：１０質量％）２５質量部、アクリロニトリル３７質量部、マレイン酸モノｎ－ブチル４質量部、ｔ－ドデシルメルカプタン（分子量調整剤）０．５質量部の順に仕込み、内部の気体を窒素で３回置換した後、ブタジエン５９質量部を仕込んだ。次いで、金属製ボトルを５℃に保ち、クメンハイドロパーオキサイド（重合開始剤）０．１部を仕込み、金属製ボトルを回転させながら１６時間重合反応を行った。そして、ハイドロキノン水溶液（重合停止剤、濃度１０質量％の）０．１部を加えて重合反応を停止させた。次いで、水温６０℃のロータリーエバポレータを用いて残留単量体を除去し、アクリロニトリル単位３７質量％、ブタジエン単位５９質量％、およびマレイン酸モノｎ－ブチル単位４質量％を有する重合体（カルボン酸基を含有するアクリロニトリル－ブタジエンゴム）のラテックス（固形分濃度：１４質量％）を得た。なお、得られたカルボン酸基を含有するアクリロニトリル－ブタジエンゴムは、メチルエチルケトンに溶解可能であった。
＜分散液の調製＞
　９９．７ｋｇのメチルエチルケトン（ＭＥＫ）と０．３ｋｇのカーボンナノチューブ（日本ゼオン社製、製品名「ＺＥＯＮＡＮＯ　ＳＧ１０１」、単層ＣＮＴ、平均直径：３．５ｎｍ）を含むＣＮＴ含有液に対して、ジェットミルを用いて分散処理を施し、分散液（ＣＮＴ濃度：０．３質量％）を得た。
＜混合工程＞
　上述のようにして得られた分散液４．６ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１ｇを滴下した（溶剤／エラストマー比：３２．８）。滴下終了後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、評価用の混合物を得た。得られた混合物を目視で確認したところ、エラストマーおよびＣＮＴが均一に混和しており、混和状態は良好であった（「混合物の混和状態」の評価結果を表１に示す）。
　また、上述のようにして得られた分散液４６００ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１０００ｇを滴下した（溶剤／エラストマー比：３２．８）。滴下後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、混合物５６００ｇを得た。
＜固形物回収工程＞
　上述の混合工程で得られた混合物５６００ｇを、攪拌下の希硫酸（ｐＨ＝４）５６０００ｇに滴下したところ、固形物（凝固物）を析出させることができた（「固形物の析出有無」の評価結果を表１に示す）。
＜水洗工程および水洗後乾燥工程＞
　上記固形物回収工程で得られた固形物を３回水洗した後乾燥して、ＣＮＴとエラストマーの複合体１３９ｇを得た。このＣＮＴとエラストマーの複合体中の分散剤量を測定した。結果を表１に示す。
＜成形体の作製工程＞
　バンバリーミキサーに、上述のようにして得られた複合体５５ｇ、カルボン酸基を含有するアクリロニトリル－ブタジエンゴム（上述「ラテックスの準備」と同様にして得られたラテックスの凝固物）５０ｇ、可塑剤（アデカ社製、製品名「アデカサイザー　Ｃ－８」）５ｇ、老化防止剤（大内新興化学工業社製、製品名「ノクラックＣＤ」）１．５ｇ、ステアリン酸１ｇ、ポリオキシエチレンアルキルエーテルリン酸エステル（東邦化学工業社製、製品名「フォスファノールＲＬ２１０」１ｇを投入し、これらを５０℃で５分間混合した。次いで、得られた混合体を５０℃のロールに移して、架橋剤（デュポン社製、製品名「Ｄｉａｋ　♯１」）２．４ｇ、１，８－ジアザビシクロ［５，４，０］－ウンデセン－７（ＤＢＵ）（ＲｈｅｉｎＣｈｅｍｉｅ社製、製品名「ＲＨＥＮＯＧＲＡＮ　ＸＬＡ－６０」４ｇを混練し、ゴム組成物を得た。このゴム組成物を金型に入れ、プレス機で加圧しながら１７０℃で２０分間プレス成形して、シート状の成形体（ゴム架橋物）を得た。得られた成形体の引裂き強度（耐引裂き性）の評価結果を表１に示す。また、この成形体表面にブリードは確認されなかった。 (Example 1)
<Preparation of latex>
In a metal bottle, 629 parts by mass of ion-exchanged water, 25 parts by mass of an aqueous solution of sodium dodecylbenzenesulfonate (concentration: 10% by mass), 37 parts by mass of acrylonitrile, 4 parts by mass of mono-n-butyl maleate, t-dodecyl mercaptan ( (Molecular weight modifier) 0.5 parts by mass were charged in order, and the inside gas was replaced with nitrogen three times, then 59 parts by mass of butadiene was charged. Next, while keeping the metal bottle at 5 ° C., 0.1 part of cumene hydroperoxide (polymerization initiator) was charged, and the polymerization reaction was carried out for 16 hours while rotating the metal bottle. Then, 0.1 part of an aqueous hydroquinone solution (polymerization terminator, concentration: 10% by mass) was added to terminate the polymerization reaction. Next, the residual monomer was removed using a rotary evaporator at a water temperature of 60 ° C., and a polymer (37% by mass of acrylonitrile unit, 59% by mass of butadiene unit, and 4% by mass of mono-n-butyl maleate unit (carboxylic acid group)) was removed. (Acrylonitrile-butadiene rubber) containing the same (solid content concentration: 14% by mass). The obtained acrylonitrile-butadiene rubber containing a carboxylic acid group was soluble in methyl ethyl ketone.
<Preparation of dispersion>
For a CNT-containing liquid containing 99.7 kg of methyl ethyl ketone (MEK) and 0.3 kg of carbon nanotubes (manufactured by Zeon Corporation, product name "ZEONANO SG101", single-walled CNT, average diameter: 3.5 nm), a jet mill is used. To give a dispersion (CNT concentration: 0.3% by mass).
<Mixing process>
While stirring 4.6 g of the dispersion obtained as described above with a stirrer, 1 g of the above latex was dropped into the dispersion (solvent / elastomer ratio: 32.8). After completion of the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain a mixture for evaluation. When the obtained mixture was visually confirmed, the elastomer and CNT were uniformly mixed, and the mixing state was good (the evaluation result of “mixing state of the mixture” is shown in Table 1).
While stirring 4600 g of the dispersion obtained as described above with a stirrer, 1000 g of the latex described above was dropped into the dispersion (solvent / elastomer ratio: 32.8). After the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain 5600 g of a mixture.
<Solid matter recovery process>
When 5600 g of the mixture obtained in the above-mentioned mixing step was dropped into 56000 g of dilute sulfuric acid (pH = 4) with stirring, a solid (coagulated product) was able to be precipitated ("presence or absence of precipitation of solid"). The evaluation results are shown in Table 1).
<Washing process and drying process after washing>
The solid obtained in the solid collecting step was washed three times with water and then dried to obtain 139 g of a composite of CNT and an elastomer. The amount of the dispersant in the composite of the CNT and the elastomer was measured. Table 1 shows the results.
<Production process of molded body>
In a Banbury mixer, 55 g of the composite obtained as described above, 50 g of acrylonitrile-butadiene rubber containing a carboxylic acid group (coagulated latex obtained in the same manner as in the above “Preparation of latex”), plasticizer ( Adeka Co., Ltd., product name "ADEKASIZER C-8") 5 g, antioxidant (Ouchi Shinko Chemical Co., Ltd., product name "Nocrack CD") 1.5 g, stearic acid 1 g, polyoxyethylene alkyl ether phosphoric acid 1 g of ester (manufactured by Toho Chemical Industry Co., Ltd., product name “Phosphanol RL210”) was added, and these were mixed at 50 ° C. for 5 minutes. Then, the obtained mixture was transferred to a roll at 50 ° C., and a crosslinking agent ( 2.4 g of 1,8-diazabicyclo [5,4,0] -undecene-7 (DBU) (RheinC, manufactured by DuPont, product name “Diak # 1”) 4 g of a product name “RHENOGRAN XLA-60” manufactured by EMIE Co., Ltd. was kneaded to obtain a rubber composition, which was put into a mold and press-molded at 170 ° C. for 20 minutes while being pressed by a press machine. A sheet-shaped molded article (crosslinked rubber) was obtained, and the evaluation results of the tear strength (tear resistance) of the obtained molded article are shown in Table 1. No bleed was observed on the surface of the molded article.
（実施例２）
　以下のようにして分散液の調製を実施した以外は、実施例１と同様にして、ラテックスを準備し、そして、混合工程、固形物回収工程、水洗工程、水洗後乾燥工程、および成形体の作製工程を実施した。そして、実施例１と同様にして各種評価を行った。結果を表１に示す。
＜分散液の調製＞
　９９．６８ｋｇのメチルエチルケトン（ＭＥＫ）、０．３ｋｇのカーボンナノチューブ（日本ゼオン社製、製品名「ＺＥＯＮＡＮＯ　ＳＧ１０１」、単層ＣＮＴ、平均直径：３．５ｎｍ）、および０．０２２ｋｇの分散剤（直鎖アルキルベンゼンスルホン酸ナトリウム）を含むＣＮＴ含有液に対して、ジェットミルを用いて分散処理を施し、分散液（ＣＮＴ濃度：０．３質量％）を得た。 (Example 2)
A latex was prepared in the same manner as in Example 1 except that a dispersion was prepared as described below, and a mixing step, a solids collecting step, a washing step, a washing and drying step, and a molding A fabrication process was performed. Various evaluations were performed in the same manner as in Example 1. Table 1 shows the results.
<Preparation of dispersion>
99.68 kg of methyl ethyl ketone (MEK), 0.3 kg of carbon nanotubes (manufactured by Zeon Corporation, product name "ZEONANO SG101", single-walled CNT, average diameter: 3.5 nm), and 0.022 kg of dispersant (linear chain) The CNT-containing liquid containing the sodium alkylbenzenesulfonate was subjected to a dispersion treatment using a jet mill to obtain a dispersion (CNT concentration: 0.3% by mass).
（比較例１）
＜ラテックスの準備＞
　実施例１と同様の、カルボン酸基を含有するアクリロニトリル－ブタジエンゴムのラテックスを準備した。
＜分散液の調製＞
　９８．５ｋｇの水、０．３ｋｇのカーボンナノチューブ（日本ゼオン社製、製品名「ＺＥＯＮＡＮＯ　ＳＧ１０１」、単層ＣＮＴ、平均直径：３．５ｎｍ）、および１．２ｋｇの分散剤（直鎖アルキルベンゼンスルホン酸ナトリウム）を含むＣＮＴ含有液に対して、ジェットミルを用いて分散処理を施し、分散液（ＣＮＴ濃度：０．３質量％）を得た。
＜混合工程＞
　上述のようにして得られた分散液５ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１ｇを滴下した（ラテックス中のエラストマーの質量に対する分散液中の水の質量の比（水／エラストマー比）：３５．６）。滴下後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、評価用の混合物を得た。得られた混合物を目視で確認したところ、エラストマーおよびＣＮＴが均一に混和しており、混和状態は良好であった（「混合物の混和状態」の評価結果を表１に示す）。
　また、上述のようにして得られた分散液５０００ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１０００ｇを滴下した（水／エラストマー比：３５．６）。滴下後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、混合物６０００ｇを得た。
＜固形物回収工程＞
　上述の混合工程で得られた混合物６０００ｇを、攪拌下の希硫酸（ｐＨ＝４）６００００ｇに滴下したところ、固形物（凝固物）を析出させることができた（「固形物の析出有無」の評価結果を表１に示す）。
＜水洗工程および水洗後乾燥工程＞
　上記固形物回収工程で得られた固形物を１３回水洗した後乾燥して、ＣＮＴとエラストマーの複合体１３６ｇを得た。このＣＮＴとエラストマーの複合体中の分散剤量を測定した。結果を表１に示す。
＜成形体の作製工程＞
　上記水洗工程および水洗後乾燥工程で得られた複合体５５．９ｇを用いた以外は、実施例１と同様にして成形体を得た。得られた成形体の引裂き強度（耐引裂き性）の評価結果を表１に示す。また、この成形体表面には、ブリードが確認された。 (Comparative Example 1)
<Preparation of latex>
A latex of acrylonitrile-butadiene rubber containing a carboxylic acid group was prepared in the same manner as in Example 1.
<Preparation of dispersion>
98.5 kg of water, 0.3 kg of carbon nanotubes (manufactured by Zeon Corporation, product name "ZEONANO SG101", single-walled CNT, average diameter: 3.5 nm), and 1.2 kg of dispersant (linear alkylbenzene sulfonic acid) The CNT-containing liquid containing (sodium) was subjected to dispersion treatment using a jet mill to obtain a dispersion (CNT concentration: 0.3% by mass).
<Mixing process>
While stirring 5 g of the dispersion obtained as described above with a stirrer, 1 g of the above latex was dropped into the dispersion (the ratio of the mass of water in the dispersion to the mass of the elastomer in the latex (water / water)). Elastomer ratio): 35.6). After the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain a mixture for evaluation. When the obtained mixture was visually confirmed, the elastomer and CNT were uniformly mixed, and the mixing state was good (the evaluation result of “mixing state of the mixture” is shown in Table 1).
Further, while stirring 5000 g of the dispersion liquid obtained as described above with a stirrer, 1000 g of the above latex was dropped into the dispersion liquid (water / elastomer ratio: 35.6). After the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain 6000 g of a mixture.
<Solid matter recovery process>
When 6000 g of the mixture obtained in the above mixing step was dropped into 60000 g of dilute sulfuric acid (pH = 4) with stirring, a solid (coagulated product) was able to be precipitated ("presence or absence of precipitation of solid"). The evaluation results are shown in Table 1).
<Washing process and drying process after washing>
The solid obtained in the solid collecting step was washed 13 times with water and then dried to obtain 136 g of a composite of CNT and an elastomer. The amount of the dispersant in the composite of the CNT and the elastomer was measured. Table 1 shows the results.
<Production process of molded body>
A molded article was obtained in the same manner as in Example 1, except that 55.9 g of the composite obtained in the above-mentioned washing step and the drying step after washing was used. Table 1 shows the evaluation results of the tear strength (tear resistance) of the obtained molded body. Bleed was confirmed on the surface of the molded body.
（比較例２）
＜ラテックスの準備＞
　実施例１と同様の、カルボン酸基を含有するアクリロニトリル－ブタジエンゴムのラテックスを準備した。
＜分散液の調製＞
　９９．７ｋｇの水と０．３ｋｇのカーボンナノチューブ（日本ゼオン社製、製品名「ＺＥＯＮＡＮＯ　ＳＧ１０１」、単層ＣＮＴ、平均直径：３．５ｎｍ）を含むＣＮＴ含有液に対して、ジェットミルを用いて分散処理を施し、分散液（ＣＮＴ濃度：０．３質量％）を得た。
＜混合工程＞
　上述のようにして得られた分散液５ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１ｇを滴下した（水／エラストマー比：３５．６）。滴下後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、評価用の混合物を得た。得られた混合物を目視で確認したところ、凝集物が発生してしまい、不均一な状態であったため、固形物回収工程以降の工程は実施しなかった（「混合物の混和状態」の評価結果を表１に示す）。 (Comparative Example 2)
<Preparation of latex>
A latex of acrylonitrile-butadiene rubber containing a carboxylic acid group was prepared in the same manner as in Example 1.
<Preparation of dispersion>
Using a jet mill, a CNT-containing liquid containing 99.7 kg of water and 0.3 kg of carbon nanotubes (manufactured by Zeon Corporation, product name "ZEONANO SG101", single-walled CNT, average diameter: 3.5 nm). A dispersion treatment was performed to obtain a dispersion liquid (CNT concentration: 0.3% by mass).
<Mixing process>
While stirring 5 g of the dispersion liquid obtained as described above with a stirrer, 1 g of the above latex was dropped into the dispersion liquid (water / elastomer ratio: 35.6). After the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain a mixture for evaluation. When the obtained mixture was visually checked, aggregates were generated and the mixture was in a non-uniform state. Therefore, the steps after the solid matter collection step were not performed (the evaluation result of the “mixed state of the mixture” was (Shown in Table 1).
（比較例３）
＜ラテックスの準備＞
　実施例１と同様の、カルボン酸基を含有するアクリロニトリル－ブタジエンゴムのラテックスを準備した。
＜分散液の調製＞
　９９．７ｋｇのメタノール（ＳＰ値：１４．５）と０．３ｋｇのカーボンナノチューブ（日本ゼオン社製、製品名「ＺＥＯＮＡＮＯ　ＳＧ１０１」、単層ＣＮＴ、平均直径：３．５ｎｍ）を含むＣＮＴ含有液に対して、ジェットミルを用いて分散処理を施し、分散液（ＣＮＴ濃度：０．３質量％）を得た。
＜混合工程＞
　上述のようにして得られた分散液５ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１ｇを滴下した（溶剤／エラストマー比：３５．６）。滴下後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、評価用の混合物を得た。得られた混合物を目視で確認したところ、凝集物が発生してしまい、不均一な状態であったため、固形物回収工程以降の工程は実施しなかった（「混合物の混和状態」の評価結果を表１に示す）。 (Comparative Example 3)
<Preparation of latex>
A latex of acrylonitrile-butadiene rubber containing a carboxylic acid group was prepared in the same manner as in Example 1.
<Preparation of dispersion>
A CNT-containing liquid containing 99.7 kg of methanol (SP value: 14.5) and 0.3 kg of carbon nanotubes (manufactured by Zeon Corporation, product name “ZEONANO SG101”, single-walled CNT, average diameter: 3.5 nm) On the other hand, a dispersion treatment was performed using a jet mill to obtain a dispersion liquid (CNT concentration: 0.3% by mass).
<Mixing process>
While stirring 5 g of the dispersion liquid obtained as described above with a stirrer, 1 g of the above latex was dropped into the dispersion liquid (solvent / elastomer ratio: 35.6). After the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain a mixture for evaluation. When the obtained mixture was visually checked, aggregates were generated and the mixture was in a non-uniform state. Therefore, the steps after the solid matter collection step were not performed (the evaluation result of the “mixed state of the mixture” was (Shown in Table 1).
（比較例４）
＜ラテックスの準備＞
　実施例１と同様の、カルボン酸基を含有するアクリロニトリル－ブタジエンゴムのラテックスを準備した。
＜分散液の調製＞
　実施例１と同様にして、分散液（ＣＮＴ濃度：０．３質量％）を得た。
＜混合工程＞
　上述のようにして得られた分散液３．３ｇをスターラーで攪拌しながら、当該分散液に、上述のラテックス１４．４ｇを滴下した（溶剤／エラストマー比：１．６）。滴下後、５分間攪拌（スターラーの回転速度：４００回転／秒）して、評価用の混合物を得た。得られた混合物を目視で確認したところ、凝集物が発生してしまい、不均一な状態であったため、固形物回収工程以降の工程は実施しなかった（「混合物の混和状態」の評価結果を表１に示す）。 (Comparative Example 4)
<Preparation of latex>
A latex of acrylonitrile-butadiene rubber containing a carboxylic acid group was prepared in the same manner as in Example 1.
<Preparation of dispersion>
In the same manner as in Example 1, a dispersion liquid (CNT concentration: 0.3% by mass) was obtained.
<Mixing process>
While stirring 3.3 g of the dispersion liquid obtained as described above with a stirrer, 14.4 g of the above latex was dropped into the dispersion liquid (solvent / elastomer ratio: 1.6). After the dropwise addition, the mixture was stirred for 5 minutes (rotation speed of a stirrer: 400 rotations / second) to obtain a mixture for evaluation. When the obtained mixture was visually checked, aggregates were generated and the mixture was in a non-uniform state. Therefore, the steps after the solid matter collection step were not performed (the evaluation result of the “mixed state of the mixture” was (Shown in Table 1).
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　表１より、エラストマーを含むラテックスと、所定範囲内にＳＰ値を有し且つラテックス中のエラストマーを溶解可能な溶剤中にＣＮＴが分散させてなる分散液とを、溶剤／エラストマー比が所定の値以上となるように混合して混合物を得て、当該混合物から固形物を回収した実施例１～２では、優れた耐引裂き性を有する成形体を形成可能なエラストマー組成物を、効率良く製造できることが分かる。
　一方、ＣＮＴを水中に分散させてなる分散液を用いた比較例１では、ＣＮＴを水中に分散させるために多くの分散剤を用いており、固形物中に残留した分散剤量が過多となったためと推察されるが、成形体の耐引裂き性が低下してしまうことが分かる。
　また、分散剤を使用せずにＣＮＴを水中に分散させて得られる分散液を用いた比較例２では、上述したように凝集物が発生してしまいエラストマーおよびＣＮＴが良好に混和した混合物を得ることができなかった。
　更に、分散液の溶剤として、ＳＰ値が所定の範囲外であるメタノールを用いた比較例３では、上述したように凝集物が発生してしまいエラストマーおよびＣＮＴが良好に混和した混合物を得ることができなかった。
　そして、エラストマーを含むラテックスと、所定範囲内にＳＰ値を有する溶剤中にＣＮＴが分散させてなる分散液とを、溶剤／エラストマー比が所定の値未満となるように混合して混合物を得た比較例４では、上述したように凝集物が発生してしまいエラストマーおよびＣＮＴが良好に混和した混合物を得ることができなかった。 As shown in Table 1, a latex containing an elastomer and a dispersion obtained by dispersing CNT in a solvent having an SP value within a predetermined range and capable of dissolving the elastomer in the latex have a solvent / elastomer ratio of a predetermined value. In Examples 1 and 2 in which a mixture was obtained by mixing as described above and a solid was recovered from the mixture, an elastomer composition capable of forming a molded article having excellent tear resistance can be efficiently produced. I understand.
On the other hand, in Comparative Example 1 using a dispersion obtained by dispersing CNTs in water, many dispersants were used to disperse the CNTs in water, and the amount of the dispersant remaining in the solid was excessive. It is guessed that the molded article had a reduced tear resistance.
In Comparative Example 2 using a dispersion obtained by dispersing CNTs in water without using a dispersant, aggregates are generated as described above, and a mixture in which the elastomer and the CNTs are well mixed is obtained. I couldn't do that.
Furthermore, in Comparative Example 3 in which methanol having an SP value outside the predetermined range was used as the solvent of the dispersion, aggregates were generated as described above, and a mixture in which the elastomer and CNT were well mixed could be obtained. could not.
Then, a latex containing an elastomer and a dispersion obtained by dispersing CNTs in a solvent having an SP value within a predetermined range were mixed so that the solvent / elastomer ratio was less than a predetermined value to obtain a mixture. In Comparative Example 4, aggregates were generated as described above, and a mixture in which the elastomer and the CNT were mixed well could not be obtained.
　本発明の製造方法によれば、耐引裂き性に優れる成形体を供給可能なエラストマー組成物を、効率良く製造することができる。 According to the production method of the present invention, an elastomer composition capable of supplying a molded article having excellent tear resistance can be efficiently produced.

Claims (5)

  1. 　エラストマーを含むラテックスと、カーボンナノチューブおよびＳＰ値が８．０（ｃａｌ／ｃｍ３）１／２以上１０．０（ｃａｌ／ｃｍ３）１／２以下であって且つ前記エラストマーを溶解可能な溶剤を含む分散液とを、前記ラテックス中の前記エラストマーの質量に対する前記分散液中の前記溶剤の質量の比が４以上となるように混合する混合工程を含む、エラストマー組成物の製造方法。 A latex containing an elastomer, a carbon nanotube and a solvent having an SP value of 8.0 (cal / cm 3 ) 1/2 or more and 10.0 (cal / cm 3 ) 1/2 or less and capable of dissolving the elastomer. A method for producing an elastomer composition, comprising a mixing step of mixing a dispersion containing the solvent with the mass of the solvent in the dispersion to the mass of the elastomer in the latex being 4 or more.
  2. 　前記エラストマーが、アクリロニトリル－ブタジエンゴム、アクリロニトリル－イソプレンゴム、アクリロニトリル－ブタジエン－イソプレンゴム、スチレン－ブタジエンゴム、ブタジエンゴム、イソプレンゴム、天然ゴム、エチレン－プロピレン－ジエンゴム、ブチルゴム、およびこれらの水素化物からなる群から選択される少なくとも１つである、請求項１に記載のエラストマー組成物の製造方法。 The elastomer comprises acrylonitrile-butadiene rubber, acrylonitrile-isoprene rubber, acrylonitrile-butadiene-isoprene rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, natural rubber, ethylene-propylene-diene rubber, butyl rubber, and hydrides thereof. The method for producing an elastomer composition according to claim 1, wherein the method is at least one selected from the group.
  3. 　前記カーボンナノチューブが、単層カーボンナノチューブである、請求項１または２に記載のエラストマー組成物の製造方法。 The method for producing an elastomer composition according to claim 1, wherein the carbon nanotube is a single-walled carbon nanotube.
  4. 　前記溶剤が、アセトン、メチルエチルケトン、テトラヒドロフラン、およびトルエンからなる群から選択される少なくとも１つである、請求項１～３の何れかに記載のエラストマー組成物の製造方法。 4. The method for producing an elastomer composition according to claim 1, wherein the solvent is at least one selected from the group consisting of acetone, methyl ethyl ketone, tetrahydrofuran, and toluene.
  5. 　前記混合工程で得られた混合物から、固形物を回収する固形物回収工程を更に含む、請求項１～４の何れかに記載のエラストマー組成物の製造方法。 (5) The method for producing an elastomer composition according to any one of (1) to (4), further comprising a solid matter collecting step of collecting a solid matter from the mixture obtained in the mixing step.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004210830A (en) * 2002-12-27 2004-07-29 Jsr Corp Elastomer composition and method for producing the same
WO2010147101A1 (en) * 2009-06-16 2010-12-23 株式会社ナノストラクチャー研究所 Carbon nanotube-rich resin composition and method for producing same
WO2013047796A1 (en) * 2011-09-29 2013-04-04 独立行政法人産業技術総合研究所 Carbon nanotube composite material
WO2014115560A1 (en) * 2013-01-24 2014-07-31 日本ゼオン株式会社 Carbon nanotube dispersion, method for manufacturing same, carbon nanotube composition, and method for manufacturing same
WO2015015758A1 (en) * 2013-07-31 2015-02-05 日本ゼオン株式会社 Method for producing carbon nanotube dispersion, method for producing composite material composition, method for producing composite material, composite material, and composite-material molded product
JP2017014314A (en) * 2015-06-26 2017-01-19 昭和電工株式会社 Manufacturing method of elastomer composition, elastomer composition, master batch and elastomer mixture
KR20170090024A (en) * 2016-01-27 2017-08-07 에스케이하이닉스 주식회사 Semiconductor package having interconnection member

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004210830A (en) * 2002-12-27 2004-07-29 Jsr Corp Elastomer composition and method for producing the same
WO2010147101A1 (en) * 2009-06-16 2010-12-23 株式会社ナノストラクチャー研究所 Carbon nanotube-rich resin composition and method for producing same
WO2013047796A1 (en) * 2011-09-29 2013-04-04 独立行政法人産業技術総合研究所 Carbon nanotube composite material
WO2014115560A1 (en) * 2013-01-24 2014-07-31 日本ゼオン株式会社 Carbon nanotube dispersion, method for manufacturing same, carbon nanotube composition, and method for manufacturing same
WO2015015758A1 (en) * 2013-07-31 2015-02-05 日本ゼオン株式会社 Method for producing carbon nanotube dispersion, method for producing composite material composition, method for producing composite material, composite material, and composite-material molded product
JP2017014314A (en) * 2015-06-26 2017-01-19 昭和電工株式会社 Manufacturing method of elastomer composition, elastomer composition, master batch and elastomer mixture
KR20170090024A (en) * 2016-01-27 2017-08-07 에스케이하이닉스 주식회사 Semiconductor package having interconnection member

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