JP6650868B2 - Method for producing rubber composition - Google Patents

Description

  The present invention relates to a method for producing a rubber composition containing a polyether-based polymer.

  BACKGROUND ART Polyether polymers are widely used as fuel hoses, air hoses, and tube materials in automotive applications by utilizing their heat resistance, oil resistance, ozone resistance, and the like. In recent years, by utilizing its unique electrical characteristics, it has been used as a rubber material for a semiconductive roller or belt for developing, charging, and transferring an electrophotographic process in a copier printer or the like.

  In the polyether polymer, reinforcing agents such as carbon black and silica gel, fillers such as calcium carbonate, clay and talc, plasticizers, cross-linking agents and the like are appropriately selected and used according to required characteristics. However, in order to expand the range of application, further improvement in mechanical properties is required.

  In addition, in the charging roll, the transfer roll, and the developing roll used in the contact charging system of the electrophotographic apparatus, in addition to the improvement of the mechanical properties described above, because of the demand for higher image quality and higher speed, the base portion is used. As the physical properties required for rubber materials, low volume resistivity and reduction in variation in volume resistivity are required.Generally, carbon black is used to impart conductivity to the rubber material as the base material. A method of adding a conductivity-imparting agent such as a metal oxide to a polyether-based polymer is used.

  In order to improve the mechanical properties, or low volume resistivity, and to reduce the amplitude of the volume resistivity, the addition of carbon black, which is a spherical particle, will have little effect, Must be added in large quantities. However, the above object can be achieved by adding a large amount, but there is a fear that other physical properties may be impaired, and more time is required for kneading (see Patent Documents 1 and 2).

JP-A-2001-316528 WO2013-146648

  Therefore, in order to improve the mechanical strength and reduce the fluctuation of the volume resistivity without deteriorating various physical properties of the polyether-based polymer, a material capable of achieving the above object with a small amount of addition is required. Have been.

  The present invention has been developed in view of the above circumstances, and provides a method for producing a polyether-based polymer-containing rubber composition having excellent mechanical strength, a low volume resistance, and a reduced swing width. The purpose is to:

  The present inventors have paid particular attention to the method of mixing the respective raw materials constituting the rubber composition, and as a result of intensive studies, have found that the above-mentioned problems can be solved. Thus, the present invention has been completed.

  That is, the present invention relates to a method for producing a rubber composition containing (a) a polyether-based polymer, comprising at least (a) a polyether-based polymer, (b) a crosslinking agent, and (c) a diameter of 0.5 nm. The present invention relates to a method for producing a rubber composition, comprising a mechanical kneading step of dry-mixing a solid carbon material having an aspect ratio of not less than 100 nm and an aspect ratio of 100 or more.

  In the method for producing a rubber composition, the mechanical kneading step preferably uses a mixing roll, a Banbury mixer, a kneader, or a kneading extruder.

  In the method for producing a rubber composition, (a) the polyether polymer contains at least one structural unit derived from a compound selected from the group consisting of ethylene oxide, propylene oxide, epichlorohydrin, and allyl glycidyl ether. Is preferred.

  In the method for producing a rubber composition, (a) the polyether-based polymer is selected from the group consisting of an epichlorohydrin homopolymer, an epichlorohydrin-ethylene oxide copolymer, and an epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer. It preferably contains at least one selected polymer.

  In the method for producing a rubber composition, it is preferable that (a) the polyether-based polymer contains a polymer containing 4 to 95 mol% of ethylene oxide, when the total of the constituent units is 100 mol%.

  In the method for producing a rubber composition, (b) the crosslinking agent is a polyamine-based crosslinking agent, a quinoxaline-based crosslinking agent, a thiourea-based crosslinking agent, a triazine-based crosslinking agent, a bisphenol-based crosslinking agent, a sulfur-based crosslinking agent, and a peroxide. It is preferable to contain at least one type of crosslinking agent selected from the group consisting of crosslinking agents.

  In the method for producing a rubber composition, the amount of the (c) solid carbon material is preferably 0.1 to 15 parts by weight based on 100 parts by weight of the (a) polyether-based polymer.

  In general, when mixing a solid carbon material having a high aspect ratio with a rubber component, in order to enhance the dispersibility of the solid carbon material, the solid carbon material is previously dispersed in a solvent such as water and an organic solvent, The wet mixing of mixing this with the rubber component is common. However, in the method for producing a rubber composition according to the present invention, at least (a) a polyether-based polymer, (b) a crosslinking agent, and (c) a solid having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more. Dry carbonaceous material (mechanical kneading method). By performing mechanical kneading in a dry state, a suitable shear force acts on the solid carbon material in the polyether-based polymer, whereby the dispersibility thereof can be increased. In addition, since no solvent is used, a step of removing the solvent by heating or the like becomes unnecessary, so that the process can be simplified, the polymer can be prevented from deteriorating due to heating, and the mechanical strength of the vulcanized rubber can be prevented from deteriorating. be able to.

  In particular, when the total of the constituent units is 100 mol%, (a) a polyether-based polymer containing 4 to 95 mol% of ethylene oxide is used, (b) a crosslinking agent, and (c) a diameter of 0.5 nm to 100 nm. When dry mixing a solid carbon material having an aspect ratio of 100 or more (mechanical kneading method), the dispersibility of the solid carbon material in the rubber composition is significantly improved, and as a result, As the mechanical strength is further improved, the amplitude of the volume resistance is significantly reduced. Although the cause is not clear, when the rubber composition is dry-mixed, the ethylene oxide unit of the polyether-based polymer and the solid carbon material interact strongly in the absence of a solvent, and as a result, the rubber composition One of the causes is considered to be that the dispersibility of the solid carbon material in the material is significantly improved.

  The crosslinked product obtained by crosslinking the rubber composition produced by the method for producing a rubber composition of the present invention is excellent in mechanical properties and reinforcing properties as a rubber material, and is a rubber sheet, a rubber tube, a rubber hose, a rubber packing, and a rubber roll. Useful for rubber belts, rubber vibration insulators, etc. Further, a cross-linked product obtained by cross-linking the rubber composition of the present invention, as a rubber material, because of a small fluctuation in volume resistivity, a semi-conductive rubber roll of a copier, a printer, and an electric or electronic material including a belt and the like. It is very useful for a member for use.

  In the method for producing a rubber composition of the present invention, at least (a) a polyether polymer, (b) a crosslinking agent, and (c) a solid carbon material having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more. And a mechanical kneading step of dry mixing.

  The (a) polyether polymer used in the present invention is generally obtained by polymerizing an oxirane compound. (A) The polyether polymer is specifically an alkylene oxide such as ethylene oxide, propylene oxide, n-butylene oxide, methyl glycidyl ether, ethyl glycidyl ether, n-glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether. Glycidyls, such as epichlorohydrin, epihalohydrins such as epibromhydrin, preferably contains structural units derived from styrene oxide, etc., ethylene oxide, propylene oxide, epichlorohydrin, a structure derived from a compound selected from allyl glycidyl ether It is preferable to include at least one unit.

As one specific example of the polyether polymer (a) used in the present invention, an epihalohydrin polymer containing a structural unit derived from epihalohydrins is specifically exemplified. The epihalohydrin polymer refers to a homopolymer of epihalohydrin or a copolymer with another epoxide copolymerizable with epihalohydrin, such as ethylene oxide, propylene oxide, and allyl glycidyl ether. Examples thereof include epichlorohydrin homopolymer, epibromohydrin homopolymer, epichlorohydrin-ethylene oxide copolymer, epibromohydrin-ethylene oxide copolymer, epichlorohydrin-propylene oxide copolymer, epibromohydrin -Propylene oxide copolymer, epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer, epibromohydrin-ethylene oxide-allyl glycidyl ether terpolymer, epichlorohydrin-ethylene oxide-propylene oxide-allyl glycidyl ether terpolymer And terpolymers of epibromohydrin-ethylene oxide-propylene oxide-allyl glycidyl ether. Although the molecular weight of these homopolymers or copolymers is not particularly limited, it is usually about ML _{1 + 4} (100 ° C.) = 30 to 150 in Mooney viscosity. These homopolymers or copolymers can be used alone or in combination of two or more.

  In the present invention, (a) the polyether-based polymer is preferably an epichlorohydrin-based polymer, and is an epichlorohydrin homopolymer, an epichlorohydrin-ethylene oxide copolymer, an epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer. It is more preferable that it is an epichlorohydrin-ethylene oxide copolymer or a terpolymer of epichlorohydrin-ethylene oxide-allyl glycidyl ether having a constitutional unit derived from ethylene oxide.

  In particular, in the present invention, from the viewpoint of (c) improving the dispersibility of the solid carbon material in the rubber composition, (a) the polyether-based polymer, when the total of the constituent units is 100 mol%, is defined as ethylene oxide. It is preferable to contain a polymer containing 4 to 95 mol%, more preferably 34 to 95 mol%, particularly preferably 50 to 95 mol%.

  In the case of the epichlorohydrin-ethylene oxide copolymer, the copolymerization ratio of the structural unit based on epichlorohydrin is preferably 5 mol% to 95 mol%, more preferably 10 mol% to 75 mol%, and more preferably 10 mol% to 65 mol%. Is particularly preferred. The constituent unit based on ethylene oxide is preferably from 5 mol% to 95 mol%, more preferably from 25 mol% to 90 mol%, particularly preferably from 35 mol% to 90 mol%.

  In the case of an epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer, the copolymerization ratio of the structural units based on epichlorohydrin is preferably 5 mol% to 95 mol%, more preferably 10 mol% to 75 mol%. It is particularly preferred that the content is 10 mol% to 65 mol%. The constituent unit based on ethylene oxide is preferably from 4 mol% to 94 mol%, more preferably from 24 mol% to 89 mol%, and particularly preferably from 34 mol% to 89 mol%. The structural unit based on allyl glycidyl ether is preferably 1 mol% to 10 mol%, more preferably 1 mol% to 8 mol%, and particularly preferably 1 mol% to 7 mol%.

The copolymer composition of the epichlorohydrin-ethylene oxide copolymer and the epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer is determined from the chlorine content and the iodine value.
The chlorine content is measured by potentiometric titration according to the method described in JIS K7229. From the obtained chlorine content, the molar fraction of the structural unit based on epichlorohydrin is calculated.
The iodine value is measured by a method according to JIS K6235. From the obtained iodine value, the mole fraction of the structural unit based on allyl glycidyl ether is calculated.
The mole fraction of the constituent unit based on ethylene oxide is calculated from the mole fraction of the constituent unit based on epichlorohydrin and the mole fraction of the constituent unit based on allyl glycidyl ether.

  In the method for producing a rubber composition of the present invention, a polymer other than (a) the polyether-based polymer can be blended into the rubber composition as long as the effects of the present invention are not impaired. (A) The polymer other than the polyether polymer is not particularly limited, but polyethylene, polypropylene, polyvinyl chloride, chlorinated polyethylene, polystyrene, polyester, nylon, ABS resin, epoxy resin, (meth) acrylate resin, phenol resin, Thermoplastic resins such as melamine resin and diallyl phthalate resin, thermosetting resins, natural rubber (NR), butadiene rubber (BR), styrene butadiene rubber (SBR), acrylonitrile butadiene rubber (NBR), isoprene rubber (IR), Butyl rubber (IIR), chloroprene rubber (CR), ethylene propylene rubber (EPM, EPDM), chlorosulfonated polyethylene (CSM), acrylic rubber (ACM, AEM), fluoro rubber (FKM), urethane rubber (U), silicone rubber Q) natural rubber, etc., synthetic rubber. Particularly preferred are polyvinyl chloride, chlorinated polyethylene, polyester, epoxy resin, (meth) acrylate resin, phenol resin, NBR, CR, CSM, ACM, AEM, and the like. The blending ratio is not particularly limited, and the blending can be performed in an arbitrary range.

  In the present invention, the crosslinking agent (b) is not particularly limited as long as it crosslinks the (a) polyether-based polymer, but a polyamine-based crosslinking agent, a quinoxaline-based crosslinking agent, a thiourea-based crosslinking agent, and a triazine-based crosslinking agent. Agents, bisphenol-based crosslinking agents, sulfur-based crosslinking agents, peroxide crosslinking agents, and the like.

  Examples of the polyamine crosslinking agent include ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenetetramine, p-phenylenediamine, cumenediamine, N, N'-dicinnamylidene-1,6-hexanediamine, ethylenediaminecarbamate, and hexamethylene Diamine carbamate and the like can be mentioned.

  Examples of the quinoxaline-based crosslinking agent include 2,3-dimercaptoquinoxaline, quinoxaline-2,3-dithiocarbonate, 6-methylquinoxaline-2,3-dithiocarbonate, and 5,8-dimethylquinoxaline-2,3-dithiocarbonate. Is mentioned.

  Examples of the thiourea-based crosslinking agent include 2-mercaptoimidazoline, 1,3-diethylthiourea, 1,3-dibutylthiourea, and trimethylthiourea.

  Examples of the triazine-based crosslinking agent include 2,4,6-trimercapto-1,3,5-triazine, 2-hexylamino-4,6-dimercaptotriazine, 2-diethylamino-4,6-dimercaptotriazine, -Cyclohexylamino-4,6-dimercaptotriazine, 2-dibutylamino-4,6-dimercaptotriazine, 2-anilino-4,6-dimercaptotriazine, 2-phenylamino-4,6-dimercaptotriazine and the like Is mentioned.

  Examples of the bisphenol-based cross-linking agent include bisphenol AF and bisphenol S.

  Examples of the sulfur-based crosslinking agent include sulfur, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram monosulfide, tetrabutylthiuram disulfide, N, N'-dimethyl-N, N'-diphenylthiuram disulfide. , Dipentamethylene thiuram monosulfide, dipentamethylene thiuram disulfide, dipentamethylene thiuram tetrasulfide, dipentamethylene thiuram hexasulfide, and other active sulfur releasing compounds.

  As the peroxide crosslinking agent, tert-butyl hydroperoxide, p-menthane hydroperoxide, dicumyl peroxide, tert-butyl peroxide, 1,3-bis (tert-butylperoxyisopropyl) benzene, 2,2 5-dimethyl-2,5-di (tert-butylperoxy) hexane, benzoyl peroxide, tert-butylperoxybenzoate and the like.

  These cross-linking agents can be used alone or in combination of two or more.

  The amount of the crosslinking agent (b) is not particularly limited, but is preferably 0.1 to 10 parts by weight, more preferably 0.3 to 5 parts by weight, based on 100 parts by weight of the (a) polyether polymer. Is particularly preferred. If the amount is less than this range, crosslinking will be insufficient, while if it exceeds this range, the crosslinked product will be too rigid, and physical properties normally expected as a crosslinked product will not be obtained.

  In the present invention, (c) a solid carbon substance having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more can be used without particular limitation. The upper limit of the aspect ratio is not particularly limited as long as the effects of the present invention are exhibited, but may be 20,000 or less, preferably 10,000 or less, more preferably 5,000 or less. Examples of the shape include a tubular shape and a horn shape, and the shape may be a multilayer structure. (C) The solid carbon substance having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more may be a carbon nanotube (single-layer or multilayer) or a carbon nanohorn.

  The aspect ratio generally means a ratio between a long side and a short side of a substance. The method of measuring the aspect ratio is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include a method of measuring with an electron microscope and the like. When the shape of the solid carbon material is cylindrical, the outer diameter of the cylindrical solid carbon material is used as the diameter for calculating the aspect ratio.

  (C) The amount of the solid carbon material having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more is not particularly limited, but (a) 0.1 to 15 parts by weight based on 100 parts by weight of the polyether polymer. Parts by weight, preferably from 0.3 to 13 parts by weight, particularly preferably from 0.5 to 12 parts by weight.

  In the production method of the present invention, as long as the effects of the present invention are not impaired, compounding agents other than those described above in the rubber composition, for example, acid acceptors, lubricants, fillers, reinforcing agents, plasticizers, processing aids, flame retardants , A foaming aid, a conductive agent, an antistatic agent, and the like, a crosslinking accelerator, a crosslinking retarder, an antioxidant, and the like can be arbitrarily compounded.

  In the present invention, a known acid acceptor may be used depending on the crosslinking, and a metal compound and / or an inorganic microporous crystal is used.

  Examples of the metal compound include Group II (oxides, hydroxides, carbonates, carboxylates, silicates, borates, phosphites, and Group IV metals of the Periodic Table). Metal compounds such as oxides, basic carbonates, basic carboxylates, basic phosphites, basic sulfites, and tribasic sulfates of lead-free metals (Groups 4 and 14) Can be

  Specific examples of the metal compound include magnesium oxide, magnesium hydroxide, barium hydroxide, magnesium carbonate, barium carbonate, sodium carbonate, quicklime, slaked lime, calcium carbonate, calcium silicate, calcium stearate, zinc stearate, and calcium phthalate. , Calcium phosphite, zinc white, tin oxide, tin stearate, basic tin phosphite, and the like. Particularly preferred acid acceptors include magnesium oxide, calcium carbonate, slaked lime, and quicklime.

  The inorganic microporous crystal means a crystalline porous body, and can be clearly distinguished from an amorphous porous body, for example, silica gel, alumina and the like. Examples of such inorganic microporous crystals include zeolites, alumina phosphate-type molecular sieves, layered silicates, hydrotalcites, alkali metal titanates, and the like. Particularly preferred acid acceptors include hydrotalcites.

  Zeolites are, in addition to natural zeolites, various zeolites such as A-type, X-type and Y-type synthetic zeolites, sodalites, natural or synthetic mordenites, ZSM-5 and the like, and metal substitutes thereof. They may be used or two or more kinds may be used in combination. Further, the metal of the metal substitute is often sodium. As zeolites, those having a large acid acceptability are preferable, and A-type zeolites are preferable.

The hydrotalcites are represented by the following general formula (1)
_{Mg X Zn Y Al Z (OH} ) (2 (X + Y) + 3Z-2) CO 3 · wH 2 O (1)
[Wherein, x and y each represent a real number of 0 to 10 having a relation of x + y = 1 to 10, z represents a real number of 1 to 5, and w represents a real number of 0 to 10, respectively].
Specific examples of the _{hydrotalcite, Mg 4.5 Al 2 (OH)} 13 CO 3 · 3.5H 2 O, Mg 4.5 Al 2 (OH) 13 CO 3, Mg 4 Al 2 (OH) 12 CO _{3 · 3.5H 2 O, Mg 5} Al 2 (OH) 14 CO 3 · 4H 2 O, Mg 3 Al 2 (OH) 10 CO 3 · 1.7H 2 O, Mg 3 ZnAl 2 (OH) 12 CO 3 _{· 3.5H 2 O, Mg 3 ZnAl} 2 (OH) may be mentioned _{12 CO 3, Mg 4.3 Al 2} (OH) 12.6 CO 3 · 3.5H 2 O and the like.

  In the present invention, when an acid acceptor is used, its content is preferably 0.2 to 50 parts by weight, preferably 1 to 20 parts by weight, based on 100 parts by weight of the polyether-based polymer (a). Is particularly preferred.

  The method for producing a rubber composition of the present invention is characterized in that it includes a mechanical kneading step of dry-mixing each material. Mechanical kneading is to physically knead each compounding agent using any mixing means conventionally used in the field of polymer processing, for example, a mixing roll, a Banbury mixer, various kneaders, a kneading extruder, or the like. . Normally, when a solid carbon material having a low dispersibility (c) having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more is mixed with a solvent such as water or an organic solvent (that is, Although it is common to disperse and mix, in the rubber composition of the present invention, the above-mentioned mechanical kneading (step) of physically kneading does not disperse (in a liquid) in a solvent, c) A rubber composition in which a solid carbon material having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more is dispersed can be obtained.

  In the present invention, "dry mixing" means mixing in a rubber composition with a content of a solvent such as water or an organic solvent of 50% by weight or less, and particularly in a state of 30% by weight or less. Means to do.

  In the mechanical kneading step, heating may be performed to shorten the kneading time, and cooling may be performed to suppress an excessive rise in temperature. As a heating method, a general method such as electric heating, steam, water, and oil is used. The cooling method is cooling with water, oil, air or the like. The temperature at the time of kneading is not particularly limited, but the kneading is usually performed in a temperature range used for rubber kneading. For example, the temperature is from room temperature to 300 ° C., preferably about 50 ° C. to 200 ° C.

  The crosslinked product of the present invention is obtained by crosslinking a rubber composition produced by the production method of the present invention (hereinafter, referred to as a crosslinking step). In the crosslinking step, crosslinking can be performed usually by heating to 100 to 200 ° C., and the crosslinking time varies depending on the temperature, but is usually between 0.5 and 300 minutes. As a heating method, an arbitrary heating method using a steam can, an air oven, a microwave, radiation, or the like can be used.

  In the crosslinking step, molding can be performed simultaneously with crosslinking. Examples of the molding method include compression molding using a mold, injection molding, and the like.

  Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples. However, the present invention is not limited to the following embodiments unless departing from the gist thereof.

  A kneading compound is obtained by dry-mixing the kneading compound A shown in Table 1 with a pressure kneader at 120 ° C. for 6 minutes (mechanical kneading step) and then dry mixing with an open roll for 5 minutes (mechanical kneading step). It was created. A kneading compounding agent (crosslinking agent, crosslinking accelerator) was added to the kneading compound A and kneading was performed for 10 minutes to prepare a kneading compound B. The obtained compound was press-crosslinked at 170 ° C. for 15 minutes to prepare a 2 mm-thick crosslinked sheet, and various measurements were performed.

The compounding agents used in Examples and Comparative Examples are shown below.
Epihalohydrin rubber 1: "Epichromer CG-102" manufactured by Daiso Co., Ltd. (the proportion of ethylene oxide is 56 mol% when the total of the structural units of the polymer is 100 mol%)
Epihalohydrin rubber 2: "Epichromer H" manufactured by Daiso Corporation (the proportion of ethylene oxide is 0 mol% when the total of the structural units of the polymer is 100 mol%)
Acrylonitrile butadiene rubber: "JSR N-230S" manufactured by JSR Corporation
Zinc oxide: "2 types of zinc oxide" manufactured by Sakai Chemical Industry Co., Ltd.
Stearic acid: "Sakura stearic acid" manufactured by NOF Corporation
Anti-aging agent 1: "Nocrack MB" manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
Anti-aging agent 2: "Nocrack 224" manufactured by Ouchi Shinko Chemical Co., Ltd.
Crosslinking accelerator 1: "Noxeller DM" manufactured by Ouchi Shinko Chemical Co., Ltd.
Crosslinking accelerator 2: "Noxeller TS" manufactured by Ouchi Shinko Chemical Co., Ltd.
Crosslinking accelerator 3: "Noxeller CZ" manufactured by Ouchi Shinko Chemical Co., Ltd.
Crosslinking accelerator 4: "Noxeller TT" manufactured by Ouchi Shinko Chemical Co., Ltd.
Crosslinking agent 1: "Kinka-in colloidal sulfur" manufactured by Tsurumi Chemical Industries
Crosslinking agent 2: "Axel 22-S" manufactured by Kawaguchi Chemical Industry Co., Ltd.
Solid carbon material 1: "SWeNT SMW200" manufactured by Aldrich (diameter 9 to 11 nm, aspect ratio 350 to 550)
Solid carbon material 2: "Seast SO" (spherical particles) manufactured by Tokai Carbon Co., Ltd.

Tensile test and hardness test A tensile test and hardness were performed using the obtained crosslinked sheet. Each evaluation test was performed according to the method described in JIS K6251 and JIS K6253-3, respectively. Table 2 shows the test results of Examples and Comparative Examples obtained by each test method. M ₁₀₀ is the tensile stress at 100% elongation specified in the tensile test of JIS K6251, Tb is the tensile strength specified in the tensile test of JIS K6251, Eb is the elongation specified in the tensile test of JIS K6251, and Hs is the hardness of JIS K6253-3. Indicates the hardness specified in the test.

Measurement of Volume Resistivity The resulting crosslinked sheet was adjusted to a condition of 23 ° C./50% RH, and then molded into a length of 80 mm, a width of 130 mm, and a thickness of 2 mm. Regarding Examples 1 to 3 and Comparative Example 2, in accordance with JIS K6271, an arbitrary 30 mm × 30 mm area in the central portion of a crosslinked product sheet formed using Mitsubishi Yuka Co., Ltd. laresta using four terminal electrodes. Were selected, and the volume resistivity was measured every 10 seconds, 30 seconds, and 50 seconds after applying 10 V and continuously applying voltage. Regarding Comparative Examples 1 and 3, any three measurement points (measurement point A) of a 20 mm × 20 mm cross-linked sheet molded using a Mitsubishi Yuka Co., Ltd. Hiresta using a double ring electrode in accordance with JIS K6271. To C), and the volume resistivity was measured every 10 seconds, 30 seconds, and 50 seconds after applying 10 V and continuously applying a voltage. Table 3 shows the results.
Regarding the fluctuation width of the volume resistivity, the maximum value of the volume resistivity measured at 10 seconds, 30 seconds and 50 seconds after each crosslinked sheet was M (Ω · cm), and the minimum value was m (Ω · cm). ) And evaluated by M / m. Table 4 shows the results.

測定点Ａ〜Ｃにおける電圧印加時間別体積抵抗率^※（Ω・ｃｍ）
※ ２３℃／５０％ＲＨ

Volume resistivity by voltage application time at measurement points A to C ^* (Ω · cm)
* 23 ℃ / 50% RH

体積抵抗率の振れ幅 Ｍ／ｍ

Runout of volume resistivity M / m

Tables 2 show that Examples 1 to 3 are excellent in mechanical properties and reinforcing properties. In particular, it can be understood that Examples 1 and 2 using an epihalohydrin-based rubber having a high ethylene oxide ratio as a constitutional unit can produce a rubber composition as a raw material of a vulcanized rubber having excellent mechanical properties and reinforcing properties. . Here, in the present invention, “good mechanical properties” means that the tensile strength Tb is large. In addition, because there is a reinforcing effect says that the large _{M 100} and Hs. Tables 3 and 4 show that Examples 1 to 3 have small fluctuations in volume resistivity. In particular, in Examples 1 and 2, the value of M / m is as close as possible to 1.00, indicating that the amplitude of the volume resistivity is extremely small.
On the other hand, Comparative Example 1 containing a solid carbon material that is a spherical particle and Comparative Example 3 not containing a solid carbon material have inferior mechanical properties and reinforcing properties as compared with Examples 1 to 3. As shown in Table 2. Further, Comparative Example 1 and Comparative Example 3 had small fluctuations in volume resistivity, but resulted in high volume resistivity itself.
Furthermore, (a) Comparative Example 2 using acrylonitrile butadiene rubber instead of the polyether-based polymer had a very large fluctuation in volume resistivity as compared with Examples 1 to 3, which was not preferable.

  The rubber material obtained by crosslinking the rubber composition produced by the production method of the present invention has excellent mechanical properties and reinforcing properties, and has a rubber sheet, a rubber tube, a rubber hose, a rubber packing, a rubber roll, a rubber belt, an anti-vibration rubber, Because of its small resistivity and small fluctuation in volume resistivity, it is usefully used for copying machines, semiconductive rubber rolls for printers, and members for electric or electronic materials including belts and the like.

Claims (6)

(A) A method for producing a rubber composition containing a polyether-based polymer,
A mechanical kneading step of dry-mixing at least (a) a polyether-based polymer, (b) a crosslinking agent, and (c) a solid carbon material having a diameter of 0.5 nm to 100 nm and an aspect ratio of 100 or more,
(A) polyether polymer is epihalohydrin polymer der is, and when the sum of the structural units was 100 mol%, the rubber composition characterized by containing a polymer containing ethylene oxide 4～95Mol% Manufacturing method.   The method for producing a rubber composition according to claim 1, wherein the mechanical kneading step uses a mixing roll, a Banbury mixer, a kneader, or a kneading extruder.   (A) The polyether polymer contains at least one structural unit derived from a compound selected from the group consisting of ethylene oxide, propylene oxide, epichlorohydrin, and allyl glycidyl ether. 3. The method for producing the rubber composition according to item 2.   (A) the polyether-based polymer is at least one polymer selected from the group consisting of epichlorohydrin homopolymer, epichlorohydrin-ethylene oxide copolymer, and epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer; The method for producing a rubber composition according to claim 1, wherein the rubber composition is contained. (B) the crosslinking agent is selected from the group consisting of polyamine-based crosslinking agents, quinoxaline-based crosslinking agents, thiourea-based crosslinking agents, triazine-based crosslinking agents, bisphenol-based crosslinking agents, sulfur-based crosslinking agents, and peroxide crosslinking agents. The method for producing a rubber composition according to any one of claims 1 to 4 , further comprising at least one crosslinking agent. The amount of (c) a solid carbonaceous material is (a) having polyether polymer 100 parts by weight, to any one of claims 1 to 5, characterized in that 0.1 to 15 parts by weight A method for producing the rubber composition as described above.