JP5338679B2 - Conductive fluorine-containing elastomer composition capable of peroxide vulcanization - Google Patents

Abstract

Disclosed is a fluoroelastomer which can be cured with a peroxide and of which electrical conductivity can be controlled. Also disclosed is a molded article produced by curing the composition. The composition comprises: (A) a fluoroelastomer composed of a constituent unit derived from vinylidene fluoride and/or a constituent unit derived from tetrafluoroethylene and a constituent unit derived from at least one monomer; (B) an electrically conductive filler in an amount of 3 to 300 parts by mass relative to 100 parts by mass of the fluoroelastomer; and (C) an organic peroxide curing agent. The composition enables the production of a cured molded article having a volume resistivity of 0.001 to 50 O.cm.

Description

  The present invention relates to a fluorine-containing elastomer composition capable of peroxide vulcanization and controllable conductivity, and a molded article obtained by vulcanizing the composition.

  Perfluorinated elastomers based on vinylidene fluoride-hexafluoropropylene (VdF-HFP) and tetrafluoroethylene (TFE) -perfluoro (alkyl vinyl ether) are superior in chemical resistance and solvent resistance. Since it exhibits heat resistance, it is widely used in fields such as the automobile industry, semiconductor industry, and chemical industry as O-rings, gaskets, hoses, stem seals, shaft seals, diaphragms, etc. used in harsh environments. .

  By the way, the peroxide-vulcanizable fluorine-containing elastomers described in JP-A-53-125491 and JP-A-62-12734 have high performance but high viscosity. In addition, various fillers (fillers) are often used as additives for fluorine-containing elastomers, but as the filler is filled, the viscosity of the composition further increases, and kneadability and fluidity during molding. There was a problem of getting worse.

  On the other hand, liquid rubber is suitable for a pumpable thermoplastic processing machine, and a liquid fluorinated elastomer containing iodine and capable of peroxide vulcanization is known (for example, JP 2000-34381 A). reference). However, the liquid fluorine-containing elastomer is intended for handling as a liquid, and it is not planned to apply a normal molding method. In addition, kneading work with a general rubber kneading device such as a liquid fluorine-containing elastomer Banbury mixer or kneader is difficult to use for reasons such as stickiness, and in order to increase the viscosity even in internal mixers and roll mixers. A device having a special cooling function is required. In addition, there is a drawback in that, if the air bubbles contained in the compound are not removed, molding defects are likely to occur. In addition, the liquid fluorine-containing elastomer that can be peroxide vulcanized contains a large amount of iodine, and therefore the cost is high, and the vulcanized product also has drawbacks such that the crosslink density becomes too high and the elongation at break is very small. .

  Further, it has been proposed to improve the processability of a composition by a peroxide vulcanizable composition comprising a fluorine-containing elastomer obtained by co-coagulation of three types of fluorine-containing elastomers having different Mooney viscosities. (See, for example, Japanese Patent Laid-Open No. 2000-34381), which is not sufficient.

In order to solve these problems, International Publication No. 2006/011547 proposes a fluorine-containing elastomer having a Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of 2 to 30 and a low viscosity. According to this fluorine-containing elastomer, it is possible to increase the filling amount of various fillers including the conductive filler due to its low viscosity, and the molding method is not limited to the conventional compression molding method and transfer molding method. It is now possible to process by extrusion molding and integral molding.

  However, in particular, since the fluorine-containing elastomer is highly insulating, a particularly large amount of conductive filler must be blended in order to impart conductivity to the elastomer composition and the molded article. Therefore, the present inventors narrowed the filler to a conductive filler as one of the developments of the pamphlet of International Publication No. 2006/011547, and specifically how much conductive molding should be blended with what conductive filler. As a result, the inventors have found a fluorine-containing elastomer composition that imparts high conductivity to a molded product.

  That is, the present invention provides (A) a fluorine-containing elastomer comprising a structural unit derived from vinylidene fluoride and / or a structural unit derived from tetrafluoroethylene and a structural unit derived from at least one further monomer, A vulcanized molded product comprising 2 to 300 parts by mass of a conductive filler and (C) an organic peroxide vulcanizing agent and having a volume resistivity of 0.001 to 50 Ω · cm with respect to 100 parts by mass of the fluorine-containing elastomer. The present invention relates to a fluorine-containing elastomer composition.

As the fluorine-containing elastomer (A), a fluorine-containing elastomer having a Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of 2 to 80 is preferable. Furthermore, the fluorine-containing elastomer (A1) having a Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of 2 to 30 is preferable from the viewpoint of excellent moldability, and from the viewpoint of good cost performance (at 100 ° C. A fluorine-containing elastomer (A2) having an upper limit of ML _{1 + 10} ) of 80 or less and a lower limit of more than 30 is preferred.

  The conductive filler (B) may be a particulate filler, a fibrous filler, or a combination thereof. In addition, conductive carbon is preferable from the viewpoint of chemical resistance.

The present invention also provides (A) a fluorine-containing elastomer comprising a structural unit derived from vinylidene fluoride and / or a structural unit derived from tetrafluoroethylene and a structural unit derived from at least one additional monomer, (B ′) It consists of 3 to 300 parts by mass of filler and (C) an organic peroxide vulcanizing agent with respect to 100 parts by mass of the fluorine-containing elastomer,
The present invention also relates to a fluorine-containing elastomer composition in which the filler (B ′) is at least one selected from the group consisting of ketjen black, acetylene black, nanoporous carbon, graphite, carbon fiber, carbon nanotube, and carbon nanofiber.

  The present invention also relates to a conductive fluorine-containing elastomer molded article having a volume resistivity of 0.001 to 50 Ω · cm obtained by peroxide vulcanizing these fluorine-containing elastomer compositions.

  The present invention includes (A) a fluorine-containing elastomer comprising a structural unit derived from vinylidene fluoride and / or a structural unit derived from tetrafluoroethylene and a structural unit derived from at least one additional monomer, (B) A vulcanized molded product comprising 3-300 parts by mass of a conductive filler and (C) an organic peroxide vulcanizing agent and having a volume resistivity of 0.001 to 50 Ω · cm is provided for 100 parts by mass of the fluoroelastomer. The present invention relates to a fluorine-containing elastomer composition.

  First, the fluorine-containing elastomer (A) will be described.

  The fluorine-containing elastomer (A) has a structural unit derived from vinylidene fluoride (VdF) and / or a structural unit derived from tetrafluoroethylene (TFE), and further a structural unit derived from at least one monomer Any copolymer may be used.

In particular,
(A1) It consists of a structural unit derived from VdF and / or a structural unit derived from TFE and a structural unit derived from at least one additional monomer, and has a Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of 2 to 30 A fluorine-containing elastomer,
(A2) It consists of a structural unit derived from VdF and / or a structural unit derived from TFE and a structural unit derived from at least one additional monomer, and has an upper limit of Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of 80 or less. And a fluorine-containing elastomer having a lower limit of more than 30.

As the fluorine-containing elastomer (A1), a fluorine-containing elastomer described in International Publication No. 2006/011547 pamphlet, that is,
(A) a structural unit derived from VdF and / or a structural unit derived from TFE and a structural unit derived from at least one additional monomer,
(A) Number average molecular weight (Mn) is 30,000 to 70,000 g / mol (b) Iodine content is 0.3 to 1.0% by weight
The fluorine-containing elastomer which can be preferably illustrated from the point which has outstanding fluidity | liquidity.

  The number average molecular weight (Mn) of the fluorine-containing elastomer (A1) is 30,000 to 70,000 g / mol, a more preferable lower limit is 35,000 g / mol, and a still more preferable lower limit is 40,000 g / mol. A preferable upper limit is 65,000 g / mol, and a more preferable upper limit is 60,000 g / mol. When the number average molecular weight (Mn) of the fluorine-containing elastomer (A1) is too small, the fluorine-containing elastomer (A1) becomes liquid, and a normal rubber kneading apparatus or molding apparatus cannot be used, and a liquid specification apparatus is used. It is not preferable because it is necessary. In addition, the number average molecular weight (Mn) of the fluorine-containing elastomer (A1) exceeds 70,000 g / mol (such as the fluorine-containing elastomer (A2) described later), which is inferior in terms of fluidity. By devising, the problem of the present invention can be solved. Further, the molecular weight distribution (weight average molecular weight Mw / number average molecular weight Mn) of the fluorine-containing elastomer (A1) is not particularly limited, but it is easy to produce that it is 1.3 or more and less than 4.0. In view of the balance of workability, it is preferable. Further, the viscosity is preferably less than 3.0 because the viscosity can be kept low.

  On the other hand, the iodine content of the fluorine-containing elastomer (A1) is 0.3 to 1.0% by weight, preferably 0.35 to 0.9% by weight, and more preferably 0.4 to 0.8% by weight. . It is preferable for the iodine content to be in this range since the balance between processability and fluidity is good.

  The fluorine-containing elastomer (A1) is not particularly limited as long as it comprises a structural unit derived from VdF and / or a structural unit derived from TFE and a structural unit derived from at least one additional monomer. Among them, those having a structural unit derived from VdF are preferable.

  Furthermore, at least one additional monomer contained in the fluorine-containing elastomer (A1) includes hexafluoropropylene (HFP), trifluoroethylene, pentafluoropropylene, vinyl fluoride, hexafluoroisobutene, chlorotrifluoroethylene ( One or more monomers selected from the group consisting of CTFE), trifluoropropylene, tetrafluoropropylene, hexafluoroisobutene, ethylene, propylene, and perfluoro (alkyl vinyl ether) which may have ether-bonded oxygen in the alkyl group It is preferable that

  Among these, as the fluorine-containing elastomer (A1), in addition to the structural unit derived from VdF, HFP, TFE, ethylene, propylene, CTFE, and an alkyl group may have ether-bonded oxygen. Having a structural unit derived from one or more monomers selected from the group consisting of fluoro (alkyl vinyl ethers) exhibits the high temperature sealing properties, chemical resistance, low gasoline permeability, etc. that are the characteristics of fluorine-containing elastomers Therefore, it is preferable. Among these, those containing perfluoro (alkyl vinyl ether) which may have ether-bonded oxygen in the alkyl group can be suitably used for the purpose of further improving cold resistance.

（Ｙ¹は炭素数１〜３のパーフルオロアルキル基、Ｘ¹はフッ素原子または水素原子、ｎは１〜４の整数である）で示される基、または、−ＯＲ_f ²であり、Ｒ_f ²はエーテル結合性酸素原子を含んでいてもよい炭素数１〜３のパーフルオロアルキル基である）
で示されるパーフルオロ（アルキルビニルエーテル）単位１５〜４５モル％
を含むことが、耐寒性や機械物性が良好な点から好ましい。The fluorine-containing elastomer (A1) is
40 to 85 mol% of VdF unit,
0 to 30 mol% of TFE units,
HFP units and / or formula (1):
CF ₂ = CF-R _f ¹ (1)
(Where R _f ¹ is

(Y ¹ is a perfluoroalkyl group having 1 to 3 carbon atoms, X ¹ is a fluorine atom or a hydrogen atom, n is an integer of 1 to 4), or —OR _f ² , R _f ² is a C 1-3 perfluoroalkyl group which may contain an etheric oxygen atom)
15 to 45 mol% perfluoro (alkyl vinyl ether) unit represented by
It is preferable from the viewpoint of good cold resistance and mechanical properties.

（式中Ｙ²は、ヨウ素原子または臭素原子、Ｘ²およびＸ³は同じかまたは異なりいずれも水素原子またはフッ素原子、Ｒ_f ²は炭素数０〜４０の好ましくは一部または全部がフッ素原子で置換された２価のアルキレン基であり、エーテル結合性酸素原子を含んでいてもよい）
で示される硬化部位モノマー単位０〜３質量％
を含むことが、特に高温におけるシール性が良好な点から好ましい。Furthermore, the fluorine-containing elastomer (A1) comprising the above units,
0.01 to 3% by mass of iodine-containing chain transfer agent unit that is a component capable of peroxide vulcanization,
Formula (2):

(Wherein Y ² is an iodine atom or a bromine atom, X ² and X ³ are the same or different, and both are a hydrogen atom or a fluorine atom, and R _f ² is preferably a fluorine atom having 0 to 40 carbon atoms. A divalent alkylene group substituted with an alkyl group, which may contain an etheric oxygen atom)
0 to 3 mass% of a curing site monomer unit represented by
It is preferable from the point with the favorable sealing performance in high temperature.

Among the compounds represented by the formula (1), perfluoro (methyl vinyl ether), perfluoro (propyl vinyl ether), CF ₂ ═CF—OCF ₂ —OCF ₂ CF ₂ CF ₃ , CF ₂ ═CF—OCF ₂ CF ₂ — OCF _{3 and the} like are particularly preferable.

  Examples of the iodine-containing chain transfer agent include monoiodoperfluoromethane, monoiodoperfluoroethane, monoiodoperfluoropropane, monoiodoperfluorobutane [for example, 2-iodoperfluorobutane, 1-iodoperfluoro (1, 1-dimethylethane)], monoiodoperfluoropentane [e.g. 1-iodoperfluoro (4-methylbutane)], 1-iodoperfluoro-n-octane, monoiodoperfluorocyclobutane, 2-iodoperfluoro (1- Cyclobutylethane) cyclohexane, monoiodoperfluorocyclohexane, monoiodotrifluorocyclobutane, monoiododifluoromethane, monoiodomonofluoromethane, 2-iodo-1-hydroperfluoroethane, 3-iodo-1- Idroperfluoropropane, monoiodomonochlorodifluoromethane, monoiododichloromonofluoromethane, 2-iodo-1,2-dichloro-1,1,2-trifluoroethane, 4-iodo-1,2-dichloroperfluorobutane 6-iodo-1,2-dichloroperfluorohexane, 4-iodo-1,2,4-trichloroperfluorobutane, 1-iodo-2,2-dihydroperfluoropropane, 1-iodo-2-hydro Perfluoropropane, monoiodotrifluoroethylene, 3-iodoperfluoropropene-1, 4-iodoperfluoropentene-1, 4-iodo-5-chloroperfluoropentene-1, 2-iodoperfluoro (1-cyclo Butenylethane), 1,3-diiodoperfluoropropane, 1,4 Diiodoperfluoro-n-butane, 1,3-diiodo-2-chloroperfluoropropane, 1,5-diiodo-2,4-dichloroperfluoro-n-pentane, 1,7-diiodoperfluoro-n -Octane, 1,2-di (iododifluoromethyl) perfluorocyclobutane, 2-iodo-1,1,1-trifluoroethane, 1-iodo-1-hydroperfluoro (2-methylethane), 2-iodo- 2,2-dichloro-1,1,1-trifluoroethane, 2-iodo-2-chloro-1,1,1-trifluoroethane, 2-iodoperfluoroethyl perfluorovinyl ether, 2-iodoperfluoroethyl Perfluoroisopropyl ether, 3-iodo-2-chloroperfluorobutyl perfluoromethylthioether, 3- Iodo-4-chloroperfluorobutyric acid, diiodomethane, 1,6-diiodoperfluorohexane, 1,6-diiodo-3,3,4,4-tetrafluorohexane, 1-bromo-2-iodoperfluoroethane, Examples thereof include 1-bromo-3-iodoperfluoropropane.

  Among these, diiodomethane, 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane, 1,6-diiodo-3 are preferable in terms of ease of synthesis, reactivity, economy, and stability. , 3,4,4-tetrafluorohexane, 1,3-diiodoperfluoropropane, 1,3-diiodo-2-chloroperfluoropropane, 1,2-di (iododifluoromethyl) perfluorocyclobutane, 1- Bromo-2-iodoperfluoroethane and 1-bromo-3-iodoperfluoropropane are particularly preferred.

  The compound represented by the formula (2) has an effect of improving the compression set by increasing the crosslink density of the vulcanized molded article by introducing iodine atoms and / or bromine atoms at locations other than the elastomer ends. Used as cure site monomer.

In addition to the formula (2), any monomer that is generally used as a curing site monomer can be suitably used. For example, some compounds overlap with the compound represented by formula (2), but specifically, the formula as disclosed in US Pat. No. 5,674,959:
CHR = CH-Z-CH ₂ CHR-I
Wherein R is a hydrogen atom or a methyl group; Z is a linear or branched C 1-18 perfluoroalkylene group optionally containing one or more ether-bonded oxygen atoms, or An oxyalkylene group) or a formula as disclosed in JP-A No. 62-12734:
XCH ₂ CF ₂ CF ₂ (OCH ₂ CF ₂ CF ₂ ) _m (OCFYCF ₂ ) _n OCF═CF ₂
(Wherein, X is an iodine atom or bromine atom; m is an integer of 0 to 5; n is an integer of 0 to 2; Y is a fluorine atom or a trifluoromethyl group). Further, iodoethylene, 4-iodo-3,3,4,4-tetrafluorobutene, 3-chloro-4-iodo-3,4,4-trifluorobutene, 2-iodo-1,1,2,2 -Tetrafluoro-1- (vinyloxy) ethane, 2-iodo-1- (perfluorovinyloxy) -1,1,2,2-tetrafluoroethylene, 1,1,2,3,3,3-hexafluoro 2-iodo-1- (perfluorovinyloxy) propane, 3,3,4,5,5,5-hexafluoro-4-iodopentene, iodotrifluoroethylene, perfluoro-4-iodobutene and the like are also suitable. Can be used.

  Non-conjugated dienes have the same effects as the above-mentioned curing site monomers, such as 1,4-pentadiene, 1,5-hexadiene, 1,7-octadiene, 3,3,4,4-tetrafluoro-1 , 5-hexadiene, 3,3,4,4,5,5,6,6-octafluoro-1,7-octadiene and the like are preferable.

  The fluorine-containing elastomer (A1) used in the present invention can be produced by the method described in International Publication No. 2006/011547.

Examples of the fluorine-containing elastomer (A2) include elastomers obtained by copolymerizing the same monomers as the fluorine-containing elastomer (A1).
(A) Number average molecular weight (Mn) is more than 70,000 g / mol and not more than 200,000 g / mol (b) Iodine content is 0.05 to 0.5% by weight
It is different in points. Examples of the fluorine-containing elastomer (A2) include relatively high-viscosity fluorine-containing elastomers described in JP-A Nos. 53-125491 and 62-12734.

  These fluorine-containing elastomers (A2) are inferior in the molding processability of the elastomer composition, but the conductivity of the molded product can be controlled by selecting the conductive filler (B).

  In addition to the fluorine-containing elastomer (A) demonstrated above, a conductive filler (B) is mix | blended with the fluorine-containing elastomer composition of this invention.

The conductive filler (B) used in the present invention refers to a filler having a volume resistivity of 1 × 10 ⁻⁹ to 1 Ω · cm. A preferred volume resistivity is 1 × 10 ⁻⁸ to 1 × 10 ⁻¹ Ω · cm.

  Examples of the conductive filler (B) include a conductive carbon filler and a metal filler.

  These conductive fillers may be particulate fillers, fibrous fillers, or combinations thereof.

  Examples of the particulate carbon filler include ketjen black, acetylene black, nanoporous carbon, graphite (natural graphite, artificial graphite), furnace black, channel black, etc. Among them, the chemical resistance and conductivity are good, and the composition From the viewpoint of good fluidity, nanoporous carbon and graphite are preferred, and from the viewpoint of good chemical resistance and electrical conductivity, ketjen black and acetylene black are preferred. The average primary particle size is preferably 0.02 to 50 μm, and more preferably 0.025 to 20 μm from the viewpoint of good conductivity.

  Examples of the fibrous carbon filler include carbon fibers, carbon nanotubes, and carbon nanofibers. Among them, carbon nanotubes and carbon nanofibers are preferable from the viewpoint of good conductivity, and carbon fibers are preferable from the viewpoint of cost performance. preferable. The diameter of the fibrous carbon is preferably 50 μm or less, preferably 0.1 to 200 nm, and more preferably 1 to 200 nm from the viewpoint of good conductivity. Further, the ratio of average fiber length / average fiber diameter is preferably 5 or more, and more preferably 10 or more from the viewpoint of good conductivity. Moreover, it is preferable from the point with the kneadability of a composition that it is 1000 or less and also 500 or less.

  In particular, the filler to be blended is preferably a filler (B ′) that is at least one selected from the group consisting of ketjen black, acetylene black, nanoporous carbon, graphite, carbon fiber, carbon nanotube, and carbon nanofiber.

  The particulate carbon filler and the fibrous carbon filler may be used in combination. When used in combination, for example, it becomes easier to control the aspect ratio of the conductivity of the molded product, which will be described later, and the electrical conductivity of the molded product is further improved than when used alone. The mixing ratio (mass ratio) of the particulate carbon filler / fibrous carbon filler is preferably 10/90 or more, and more preferably 20/80 or more from the viewpoint of giving good fluidity to the composition. Further, it is preferably 90/10 or less, and more preferably 80/20 or less from the viewpoint of easy control of the conductive aspect ratio in the molded product.

  Examples of particulate metal fillers include metal powders such as iron, silver, copper, stainless steel, aluminum, and nickel, and conductive metal oxide powders such as zirconium oxide. A powder is preferred. The average particle size is preferably 200 nm or more from the viewpoint of good kneadability of the composition. Moreover, it is preferable from the point with the intensity | strength characteristic of a molded article that it is 10 micrometers or less, Furthermore, 5 micrometers or less.

  Examples of the fibrous metal filler include the metal fibers, conductive metal oxide fibers, and metal-coated synthetic fibers, and among them, metal fibers are preferable from the viewpoint of good conductivity. The average diameter of the fibrous metal filler is preferably 5 μm or more, and more preferably 6 μm or more from the viewpoint of good conductivity. Further, it is preferably 15 μm or less, more preferably 12 μm or less from the viewpoint of good strength characteristics and surface smoothness of the molded product.

  The particulate metal filler and the fibrous metal filler may be used in combination. When used in combination, for example, the effect is obtained that the conductive aspect ratio of the molded product described later can be more easily controlled. The mixing ratio (mass ratio) of the particulate metal filler / fibrous metal filler is 10/90 or more, more preferably 20/80 or more from the point of giving good fluidity to the composition. preferable. Moreover, 90/10 or less, more preferably 80/20 or less, is preferable from the viewpoint of good control of the conductive aspect ratio in the molded product.

  The compounding quantity of an electroconductive filler (B) is 3-300 mass parts with respect to 100 mass parts of fluorine-containing elastomer (A). When the amount is less than 3 parts by mass, the conductivity of the molded product becomes insufficient, which is not preferable. On the other hand, when it exceeds 300 mass parts, the workability of a composition will fall remarkably and is unpreferable. A preferred lower limit is 5 parts by mass from the viewpoint of good conductivity of the molded product. A preferred upper limit is 200 parts by mass from the viewpoint of good stability during molding, and 150 parts by mass from the viewpoint of good moldability. Within this range, a conductive carbon filler and a metal filler may be used in combination. These combinations include particulate carbon fillers and particulate and / or fibrous metal fillers, fibrous carbon fillers and particulate and / or fibrous metal fillers. Select as appropriate. Further, the mixing ratio may be appropriately selected in consideration of the degree of conductivity, weight, kneadability and the like of each filler.

  In addition to or in place of the conductive filler (B), a nonconductive filler (volume resistivity exceeds 1 Ω · cm) may be used in combination. Examples of the nonconductive filler include a nonconductive carbon filler, a nonconductive inorganic oxide filler, and a nonconductive resin filler. Specifically, non-conductive carbon black, non-conductive Austin black, non-conductive graphite (natural graphite, artificial graphite), non-conductive carbon nanotube, non-conductive graphitized carbon black, etc. Carbon filler; non-conductive such as silica, silicate, clay, diatomaceous earth, montmorillonite, talc, calcium carbonate, calcium silicate, barium sulfate, fatty acid calcium, titanium oxide, bengara, boron nitride, aluminum nitride, magnesium oxide, alumina Inorganic oxide filler; polyethylene, heat-resistant engineering plastics, PTFE-based tetrafluoroethylene and ethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVdF), etc. Rimmer, such as a non-conductive resin filler such as polyimide and the like. The blending amount may be appropriately selected in consideration of the effect of blending, the degree of conductivity and weight of the conductive filler (B), kneadability and the like.

  An organic peroxide vulcanizing agent (C) is further added to the conductive fluorine-containing elastomer composition of the present invention. Furthermore, a polyfunctional vulcanization aid (D) may be included.

  The organic peroxide vulcanizing agent (C) used in the present invention may be a peroxide vulcanizing agent such as α, α′-bis (t-butylperoxy) diisopropylbenzene, 2, 5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide, benzoyl peroxide, 1,1-bis (t-butylperoxy) -2-methylcyclohexane, 1,1-bis (T-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5- Trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, t-hexylperoxybe Zoate, 2,5-cymethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxyacetate, 2,2-bis (t-butylperoxy) butane, t-butylperoxybenzoate, n- Butyl-4,4-bis (t-butylperoxy) valerate, di-t-butylperoxyisophthalate, t-butylcumyl peroxide, di-t-butylperoxide, p-methanehydroperoxide, 2, An organic peroxide such as 5-dimethyl-2,5-di (t-butylperoxy) hexane-3 or diisopropylbenzene hydroperoxide may be used. As the organic peroxide vulcanizing agent (C), 2,5-dimethyl-2,5-di (t-butylperoxy) hexane is preferable from the viewpoint of good vulcanizability and handleability.

  The compounding amount of the organic peroxide vulcanizing agent (C) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer (A). is there. If the vulcanizing agent is less than 0.01 parts by mass, the degree of vulcanization is insufficient, and the performance of the molded product tends to be impaired, and a vulcanizing agent exceeding 10 parts by mass is usually unnecessary. However, when highly blending the conductive filler (B), the blending amount of the organic peroxide vulcanizing agent (C) is preferably 0.5 to 10 parts by mass in order to reduce the viscosity of the composition.

  As the polyfunctional vulcanization auxiliary (D), triallyl cyanurate, triallyl isocyanurate (TAIC), tris (diallylamine-s-triazine), triallyl phosphite, N, N-diallylacrylamide, hexaallylphospho Luamide, N, N, N ′, N′-tetraallyltetraphthalamide, N, N, N ′, N′-tetraallylmalonamide, trivinyl isocyanurate, 2,4,6-trivinylmethyltrisiloxane , Tri (5-norbornene-2-methylene) cyanurate and the like. Among these, triallyl isocyanurate (TAIC) is preferable from the viewpoint of good vulcanizability and physical properties of the vulcanizate.

  The compounding amount of the polyfunctional vulcanization aid (D) is preferably 0.01 to 20 parts by mass, more preferably 0.05 to 10 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer (A). 0.1 to 5.0 parts by mass is more preferable. If the polyfunctional vulcanization aid (D) is less than 0.01 parts by mass, the vulcanization time tends to be long, and if it exceeds 20 parts by mass, it causes mold contamination and molding defects. However, when highly blending the conductive filler (B), the blending amount of the polyfunctional vulcanization aid (D) is preferably 1.0 to 20 parts by mass in order to reduce the viscosity of the composition.

  Furthermore, a processing aid and an adhesive (silane coupling agent, epoxy, phenol resin system) that is cured by crosslinking according to the present invention may be used as long as the object of the present invention is not impaired.

  The composition of the present invention can be prepared by kneading each component by an ordinary kneading method applied to the elastomer composition.

  The present invention also relates to a conductive fluorine-containing elastomer molded article obtained by molding the fluorine-containing elastomer composition of the present invention and vulcanizing the peroxide.

  There is no particular limitation on the molding method, and for example, compression molding, extrusion molding, transfer molding, and the like can be applied. However, it is particularly suitable for injection molding and integral molding with a resin that is a more advanced molding method.

  The peroxide vulcanization method is not particularly limited, and for example, vulcanization means such as steam vulcanization or vulcanization in a heating medium can be employed. It should be noted that even when secondary vulcanization is omitted at the time of molding, it is preferable that the compression set is at a satisfactory level.

  The conductive fluorine-containing elastomer molded article of the present invention can be controlled so that the volume resistivity is in the range of 0.001 to 50 Ω · cm as a measure of the conductivity. The volume resistivity can be controlled in accordance with its use and required characteristics, and is preferably low from the viewpoint of conductivity. For example, 0.001 to 10 Ω · cm, and further including high conductivity of 1 Ω · cm or less. A fluoroelastomer molded article can be provided.

  In addition, the conductive aspect ratio can be controlled by appropriately selecting the type and shape (particulate or fibrous) of the conductive filler (B), mixing of a plurality of fillers, and imparting shearing force to the composition. Here, the conductive aspect ratio means the ratio of volume resistivity in two directions perpendicularly intersecting. By controlling the conductive aspect ratio, for example, when used for a heater or the like, it is advantageous in that it is easy to suppress abnormal heat generation due to defects.

  The conductive fluorine-containing elastomer molded product of the present invention is suitable as a molded product that requires electrical conductivity, such as an electrode, a heater, an antistatic material, a charging roll for a copying machine, a high voltage blocking material, and an electromagnetic shield.

  In addition, the conductive sealing material around the semiconductor wafer chip and the conductive sealing material of the fuel cell separator need to be precisely molded, and can be easily obtained by using the composition of the present invention having excellent molding processability. Can be manufactured.

  Moreover, when using the fluorine-containing elastomer composition of the present invention, particularly a composition using the fluorine-containing elastomer (A1), a thin conductive elastomer sheet having a thickness of 0.1 to 0.5 mm can be produced. Can be expanded and performance can be improved.

  Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

<Mooney viscosity>
Measured according to ASTM-D1646 and JIS K6300.
Measuring equipment: ALPHA TECHNOLOGIES MV2000E type rotor rotation speed: 2rpm
Measurement temperature: 100 ° C

<100% modulus (M100)>
Each composition is subjected to primary press vulcanization and secondary oven vulcanization under the following standard vulcanization conditions to form a sheet having a thickness of 2 mm, and the measurement is performed according to JIS-K6251.

(Standard vulcanization conditions)
Kneading method: Roll kneading Primary press vulcanization: 10 minutes at 160 ° C Secondary oven vulcanization: 4 hours at 180 ° C

<Tensile breaking strength (Tb) and tensile breaking elongation (Eb)>
Each composition is subjected to primary press vulcanization and secondary oven vulcanization under standard vulcanization conditions to obtain a sheet having a thickness of 2 mm, and the measurement is performed according to JIS-K6251.

<Hardness (Hs) Shore A>
Each composition is subjected to primary press vulcanization and secondary oven vulcanization under standard vulcanization conditions to obtain a sheet having a thickness of 2 mm and measured (peak value) according to JIS-K6253.

<Vulcanization characteristics>
At the time of primary press vulcanization, a vulcanization curve at 160 ° C. is obtained using a JSR type curlastometer V type, and the minimum viscosity (ML), vulcanization degree (MH), induction time (T ₁₀ ) and optimum vulcanization time ( _T90 ) is obtained.

<Volume resistivity>
It measured by the following method according to the range of volume resistivity.

(1) Measurement of low volume resistance products (less than 1 × 10 ⁵ Ω · cm)
A sample having a thickness of 2.2 mm, a width of 26 mm, and a length of 60 mm is prepared, and volume resistivity is measured in accordance with JIS K7194. The measuring device is LorestaMP (product name: MCP-T350) manufactured by Mitsubishi Chemical Corporation, and the volume resistivity is measured by the four-probe method.

(2) Measurement of high volume resistance products (1 × 10 ⁵ Ω · cm or more)
A sample having a thickness of 2.2 mm, a width of 26 mm, and a length of 60 mm is prepared, and volume resistivity is measured by a four-probe method in accordance with JIS K6911. A measuring device uses a digital ultrahigh resistance / microammeter R8340A manufactured by Advantest.

Example 1
A composition having the following composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2.0 mm).

(A) Fluorine-containing elastomer 100 parts by mass (B) Conductive filler 100 parts by mass (C) Organic peroxide vulcanizing agent 1.5 parts by mass (D) Multifunctional vulcanization auxiliary 4 parts by mass

Each component is as follows.
(A) Fluorine-containing elastomer:
Composition: VdF / HFP = 77/23 (molar ratio)
Number average molecular weight (Mn): 47500 g / mol Weight average molecular weight (Mw): 66400 g / mol Molecular weight distribution (Mw / Mn): 1.40
Iodine content: 0.48% by mass
Mooney viscosity (ML _{1 + 10 at} 100 ° C.): 7
It is produced by the method described in WO 2004/009647. Hereinafter, it is referred to as a fluorine-containing elastomer (A-1).
(B) Conductive filler:
Type: Conductive graphite (Artificial graphite HAG-15 manufactured by Nippon Graphite Co., Ltd.)
Average particle size: 10 μm
(C) Organic peroxide vulcanizing agent:
Type: 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (D) polyfunctional vulcanization aid:
Type: triallyl isocyanurate (TAIC)

The Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of the obtained fluorine-containing elastomer composition was 22. Table 1 shows the vulcanization characteristics.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 2
In Example 1, except that the blending amount of the conductive filler was changed to 150 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 1, and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

  The conductivity level (0.09 Ω · cm) obtained in this example is a region called a highly conductive material, and can be compatible with good workability. In addition, when voltage is applied to this molded product, heat generation is observed, so that it can be used as a heater or an electrode.

Example 3
In Example 1, the composition was prepared by roll kneading in the same manner as in Example 1 except that the following were used as the fluorine-containing elastomer (A), vulcanized and molded under the above standard vulcanization conditions, and conductive. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

(A) Fluorine-containing elastomer:
Composition: VdF / HFP = 78/22 (molar ratio)
Number average molecular weight (Mn): 113500 g / mol Weight average molecular weight (Mw): 151900 g / mol Molecular weight distribution (Mw / Mn): 1.33
Iodine content: 0.18% by mass
Mooney viscosity (ML _{1 + 10 at} 100 ° C.): 67
Hereinafter, it is referred to as a fluorine-containing elastomer (A-2).

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 4
In Example 3, except that the blending amount of the conductive filler was changed to 150 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 3, and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 5
In Example 1, except that the following were used as the conductive filler, the composition was prepared by roll kneading in the same manner as in Example 1, vulcanized and molded under the above standard vulcanization conditions, and the conductive fluorine-containing elastomer. A sheet (thickness 2 mm) was obtained.

(B) Conductive filler:
Type: Conductive carbon fiber (Kureha Chemical Industry Kureha Carbon Fiber M-107T)
Average fiber diameter: 18 μm
Average fiber length: 700 μm
Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 6
In Example 5, the composition was prepared by roll kneading in the same manner as in Example 5 except that the blending amount of the conductive filler was changed to 150 parts by mass, and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 7
In Example 5, the composition was prepared by roll kneading in the same manner as in Example 5 except that (A-2) used in Example 3 was used as the fluorine-containing elastomer (A). Was vulcanized to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 8
In Example 1, the composition was prepared in the same manner as in Example 1 except that 50 parts by mass of the conductive graphite used in Example 1 and 50 parts by mass of the conductive carbon fiber used in Example 5 were used in combination as the conductive filler. It was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

The resulting fluorine-containing elastomer composition had a Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of 15.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 9
In Example 1, except that the blending amount of the conductive filler was changed to 60 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 1, and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Comparative Example 1
In Example 5, the same amount of MT carbon (Thermax N990 manufactured by Cancarb) was used instead of the conductive filler, and the composition was prepared by roll kneading in the same manner as in Example 5, and the above standard vulcanization conditions were used. Vulcanization molding was performed to obtain a fluorine-containing elastomer sheet (thickness 2 mm).

The Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of the obtained fluorine-containing elastomer composition was 18. Furthermore, the vulcanization characteristics of the fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Comparative Example 2
In Example 7, a composition was prepared by roll kneading in the same manner as in Example 7 except that the same amount of MT carbon (Thermax N990 manufactured by Cancarb) was used instead of the conductive filler. Vulcanization molding was performed to obtain a fluorine-containing elastomer sheet (thickness 2 mm).

The Mooney viscosity (ML _{1 + 10 at} 100 ° C.) of the obtained fluorine-containing elastomer composition was 113. Furthermore, the vulcanization characteristics of the fluorine-containing elastomer composition were examined. The results are shown in Table 1.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 1.

Example 10
In Example 5, except that the following were used as the conductive filler, a composition was prepared by roll kneading in the same manner as in Example 5, vulcanized and molded under the above standard vulcanization conditions, and a conductive fluorine-containing elastomer. A sheet (thickness 2 mm) was obtained.

(B) Conductive filler:
Type: Conductive graphite (Earth graphite HOP manufactured by Nippon Graphite Co., Ltd.)
Average particle size: 4 μm

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 11
In Example 10, except that the blending amount of the conductive filler was changed to 60 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 10, vulcanized and molded under the above standard vulcanization conditions, and conductive. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 2.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 12
In Example 5, except that the following were used as the conductive filler, a composition was prepared by roll kneading in the same manner as in Example 5, vulcanized and molded under the above standard vulcanization conditions, and a conductive fluorine-containing elastomer. A sheet (thickness 2 mm) was obtained.

(B) Conductive filler:
Type: Conductive graphite (scale graphite JB-5 manufactured by Nippon Graphite Co., Ltd.)
Average particle size: 10 μm

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 13
In Example 12, the composition was prepared by roll kneading in the same manner as in Example 12 except that the blending amount of the conductive filler was changed to 60 parts by mass, and vulcanized and molded under the standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 2.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 14
In Example 5, the following were used as the conductive filler, and the composition was prepared by roll kneading in the same manner as in Example 5 except that the blending amount was changed to 20 parts by mass. Vulcanization molding was performed to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

(B) Conductive filler:
Type: Ketjen Black (ECP-600JD manufactured by Lion Corporation)
Average particle size: 30 μm
Volume resistivity: 0.1Ω · cm

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 15
In Example 5, the following were used as the conductive filler, and the composition was prepared by roll kneading in the same manner as in Example 5 except that the blending amount was changed to 20 parts by mass. Vulcanization molding was performed to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

(B) Conductive filler:
Type: Acetylene black (Denka Black manufactured by Denki Kagaku Kogyo Co., Ltd.)
Average particle size: 40 μm
Volume resistivity: 0.2Ω · cm

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 2.

  In addition, mechanical properties (100% modulus, tensile strength at break, tensile elongation at break), hardness, and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 16
In Example 15, except that the blending amount of the conductive filler was changed to 60 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 15, and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 17
In Example 5, the following were used as the conductive filler, and the composition was prepared by roll kneading in the same manner as in Example 5 except that the blending amount was changed to 60 parts by mass. Vulcanization molding was performed to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

(B) Conductive filler:
Type: Conductive nanoporous carbon (Nanoporous carbon manufactured by Easy-N)
Average particle size: 35 nm

Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 2.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 2.

Example 18
In Example 5, except that the following were used as the conductive filler, a composition was prepared by roll kneading in the same manner as in Example 5, vulcanized and molded under the above standard vulcanization conditions, and a conductive fluorine-containing elastomer. A sheet (thickness 2 mm) was obtained.

(B) Conductive filler:
Type: Conductive carbon nanofiber (VGCF manufactured by Showa Denko KK)
Average fiber diameter: 150 nm
Average fiber length: 15 μm
Volume resistivity: 0.012 Ω · cm

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 3.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 19
In Example 18, except that the blending amount of the conductive filler was changed to 60 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 18 and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 3.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 20
In Example 18, except that the blending amount of the conductive filler was changed to 20 parts by mass, the composition was prepared by roll kneading in the same manner as in Example 18, and vulcanized and molded under the above standard vulcanization conditions. A fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 3.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 21
In Example 18, 20 parts by mass of conductive carbon nanofibers (VGCF) used in Example 18 and 2 parts by mass of acetylene black used in Example 15 were used in the same manner as Example 18 as the conductive filler. The composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 22
In Example 18, the same procedure as in Example 18 was conducted except that 20 parts by mass of conductive carbon nanofibers (VGCF) used in Example 18 and 20 parts by mass of acetylene black used in Example 15 were used as the conductive filler. The composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 3.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 23
In Example 18, 60 parts by mass of conductive carbon nanofiber (VGCF) used in Example 18 and 20 parts by mass of acetylene black used in Example 15 were used in the same manner as Example 18 as the conductive filler. The composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  The obtained molded article was examined for mechanical properties (100% modulus, tensile breaking strength, tensile breaking elongation), hardness, and volume resistivity. The results are shown in Table 3.

Example 24
In Example 18, 20 parts by mass of conductive carbon nanofiber (VGCF) used in Example 18 and 60 parts by mass of acetylene black used in Example 15 were used in the same manner as Example 18 as the conductive filler. The composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 25
In Example 18, 100 parts by mass of conductive carbon nanofiber (VGCF) used in Example 18 and 10 parts by mass of acetylene black used in Example 15 were used in the same manner as Example 18 as the conductive filler. The composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 26
In Example 5, the following were used as the conductive filler, and the composition was prepared by roll kneading in the same manner as in Example 5 except that the blending amount was changed to 11 parts by mass. Vulcanization molding was performed to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

(B) Conductive filler:
Type: Conductive carbon nanofiber (CNF-T manufactured by Gemco)
Average fiber diameter: 15 nm
Average fiber length: 1μm
Volume resistivity: 0.02 Ω · cm

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 27
In Example 26, the composition was prepared by roll kneading in the same manner as in Example 26 except that the blending amount of the conductive filler was changed to 5.5 parts by mass, and vulcanized and molded under the above standard vulcanization conditions. A conductive fluorine-containing elastomer sheet (thickness 2 mm) was obtained.

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 28
Example 26 is the same as Example 26 except that 11 parts by mass of the conductive carbon nanofibers used in Example 26 and 20 parts by mass of the conductive carbon nanofibers (VGCF) used in Example 18 were used in combination as the conductive filler. Similarly, the composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  Vulcanization characteristics of the obtained fluorine-containing elastomer composition were examined. The results are shown in Table 3.

  In addition, the mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

Example 29
Example 26 is the same as Example 26 except that 11 parts by mass of the conductive carbon nanofibers used in Example 26 and 60 parts by mass of the conductive carbon nanofibers (VGCF) used in Example 18 were used in combination as the conductive filler. Similarly, the composition was prepared by roll kneading and vulcanized and molded under the above standard vulcanization conditions to obtain a conductive fluorine-containing elastomer sheet (thickness 2 mm).

  The mechanical properties and volume resistivity of the obtained molded product were examined. The results are shown in Table 3.

  From Tables 1 to 3, it can be seen that a fluorine-containing elastomer molded product with improved conductivity can be obtained by highly filling the conductive filler. It can be seen that with the fibrous carbon filler, the smaller the average fiber diameter, the better the fluorine-containing elastomer molded product. In particular, it can be seen that a good fluorine-containing elastomer molded product can be obtained even if a small amount of carbon nanofiber is added. Moreover, it turns out that it is possible to improve the electroconductivity of a fluorine-containing elastomer molded article effectively also about combined use of two types of carbon.

  According to the present invention, it is possible to provide a fluorine-containing elastomer composition capable of peroxide vulcanization and controllable conductivity, and a molded product obtained by vulcanizing the composition.

  Moreover, by selecting a fluorine-containing elastomer, it is possible to provide a conductive fluorine-containing elastomer composition capable of precise molding and a molded product thereof.

Claims (3)

(A) a fluorine-containing elastomer comprising a structural unit derived from vinylidene fluoride and / or a structural unit derived from tetrafluoroethylene and a structural unit derived from at least one further monomer, (B) 100 mass of the fluorine-containing elastomer 3 to 300 parts by mass of conductive filler and (C) an organic peroxide vulcanizing agent,
The fluorine-containing elastomer (A) is a fluorine-containing elastomer having a Mooney viscosity (ML _{1 + 10 at} 100 ° C. ) of 2 to 80,
The conductive filler (B) is a combination of a particulate carbon filler and a fibrous carbon filler,
And a fluorine-containing elastomer composition which gives a vulcanized molded product having a volume resistivity of 0.001 to 50 Ω · cm. (A) a fluorine-containing elastomer comprising a structural unit derived from vinylidene fluoride and / or a structural unit derived from tetrafluoroethylene and a structural unit derived from at least one further monomer, (B ′) the fluorine-containing elastomer 100 3 to 300 parts by mass of filler and (C) an organic peroxide vulcanizing agent,
The filler (B ′) is selected from the group consisting of at least one particulate carbon filler selected from the group consisting of ketjen black, acetylene black, nanoporous carbon and graphite, and the group consisting of carbon fibers, carbon nanotubes and carbon nanofibers. a combination of at least 1 Tanedea Ru fibrous carbon filler,
The fluorine-containing elastomer (A) is a fluorine-containing elastomer der Ru fluorinated elastomers composition _{(ML 1 + 10} at 100 ° C.) Mooney viscosity of 2 to 80. A conductive fluorine-containing elastomer molded article having a volume resistivity of 0.001 to 50 Ω · cm obtained by peroxide vulcanization of the fluorine-containing elastomer composition according to claim 1 .