JP2013028664A - Electroconductive thermoset film and method for producing the same - Google Patents

Abstract

Disclosed is a conductive thermosetting film that includes a thermosetting crosslinked cyclic olefin resin obtained by ring-opening metathesis polymerization of a cyclic olefin monomer and has high conductivity and flexibility.
A conductive thermosetting film is obtained by ring-opening metathesis polymerization of a polymerizable composition containing (a) 100 parts by mass of a cyclic olefin monomer and (b) 50 to 200 parts by mass of artificial graphite. The pH of the artificial graphite aqueous dispersion is 7.0 or more, and the average particle size of the artificial graphite (b) is 4.5 to 15 μm.
[Selection figure] None

Description

  The present invention relates to a conductive thermosetting film having high conductivity and flexibility and a method for producing the same.

Conventionally, a metal or a carbon material has been used as a material requiring high conductivity. In recent years, lightweight materials have been required for highly conductive materials, and composite materials including polymer materials and carbon materials have been studied. (A) A conductive curable resin containing an elastomer having a Mooney viscosity (ML _{1 + 4} (100 ° C.)) of 25 or more and a carbon material such as (B) graphite powder, artificial graphite powder, natural graphite powder, expanded graphite powder A method for producing a sheet cured body in which an uncured sheet obtained by molding the composition is cut or punched out and thermally cured has been studied (for example, see Patent Document 1).

  On the other hand, a laminate having a layer formed of a resin molded body obtained by bulk metathesis polymerization of a cyclic olefin monomer using a metathesis polymerization catalyst and a layer formed of amorphous carbon has been studied (for example, see Patent Document 2).

JP 2003-176327 A JP 2004-249493 A

The cyclic olefin monomer is subjected to molding together with a polymerization reaction to give a molded body. Therefore, recently, in order to reduce the production process, a film having high conductivity and flexibility including a thermosetting crosslinked cyclic olefin resin obtained by ring-opening metathesis polymerization of a cyclic olefin monomer has been demanded. No such film has been found.
Problems to be solved by the present invention include a thermosetting crosslinked cyclic olefin resin obtained by ring-opening metathesis polymerization of a cyclic olefin monomer, and a highly conductive and flexible conductive thermosetting film and a method for producing the same. Is an offer.

  As a result of intensive studies, the inventors of the present invention have obtained a conductive thermosetting film obtained by ring-opening metathesis polymerization of a polymerizable composition containing (a) a cyclic olefin monomer and (b) specific artificial graphite. It has been found that it has high conductivity and flexibility, and has completed the conductive thermosetting film of the present invention and its production method.

  The conductive thermosetting film of the present invention is obtained by ring-opening metathesis polymerization of a polymerizable composition containing (a) 100 parts by mass of a cyclic olefin monomer and (b) 50 to 200 parts by mass of artificial graphite. ) The pH of the aqueous dispersion of artificial graphite is 7.0 or more, and the average particle size of (b) artificial graphite is 4.5 to 15 μm. The preferred (a) cyclic olefin monomer is a norbornene monomer.

In the method for producing a conductive thermosetting film of the present invention, a polymerizable composition containing (a) 100 parts by mass of a cyclic olefin monomer and (b) 50 to 200 parts by mass of artificial graphite is present in a composition containing a polymerization catalyst. Including a step of ring-opening metathesis polymerization, wherein the pH of the aqueous dispersion of (b) artificial graphite is 7.0 or more, and the average particle size of (b) artificial graphite is 4.5 to 15 μm.
The preferred (a) cyclic olefin monomer is a norbornene monomer. Preferably, a composition containing the polymerizable composition and the polymerization catalyst is applied onto a support, and ring-opening metathesis polymerization is performed on the support. The preferred polymerization catalyst is a ruthenium carbene complex.

  The conductive thermosetting film of the present invention has high conductivity and flexibility. The method for producing a conductive thermosetting film of the present invention provides a conductive thermosetting film having high conductivity and flexibility with a small number of steps.

(A) The cyclic olefin monomer, which is one of the raw materials for the conductive thermosetting film of the present invention, is a compound having a ring structure formed of carbon atoms and having a carbon-carbon double bond in the ring. . Specific examples thereof include norbornene monomers and monocyclic olefins. The preferred (a) cyclic olefin monomer is a norbornene monomer. The norbornene-based monomer is a monomer containing a norbornene ring. Specific examples of the norbornene monomer include norbornenes, dicyclopentadiene, and tetracyclododecenes. These may contain as substituents hydrocarbon groups such as alkyl groups, alkenyl groups, alkylidene groups, and aryl groups; polar groups such as carboxyl groups and acid anhydride groups.
The norbornene monomer may further have a double bond in addition to the double bond of the norbornene ring. From the viewpoint of improving the releasability of the release film, preferred norbornene monomers are nonpolar monomers, that is, norbornene monomers composed only of carbon atoms and hydrogen atoms.

  Specific examples of the nonpolar norbornene monomer include nonpolar such as dicyclopentadiene, methyldicyclopentadiene, and dihydrodicyclopentadiene (also referred to as tricyclo [5.2.1.02,6] dec-8-ene). Of dicyclopentadiene;

  Tetracyclo [6.2.13,6.02,7] dodec-4-ene, 9-methyltetracyclo [6.2.13,6.02,7] dodec-4-ene, 9- Ethyltetracyclo [6.2.13,6.02,7] dodec-4-ene, 9-cyclohexyltetracyclo [6.2.1.13,6.02,7] dodec-4-ene, 9-cyclopentyltetracyclo [6.2.13,6.02,7] dodec-4-ene, 9-methylenetetracyclo [6.2.13,6.02,7] dodec-4- Ene, 9-ethylidenetetracyclo [6.2.13,6.02,7] dodec-4-ene, 9-vinyltetracyclo [6.2.13,6.02,7] dodeca 4-ene, 9-propenyltetracyclo [6.2.13, 6.02,7] dodec-4-e 9-cyclohexenyltetracyclo [6.2.13, 6.02,7] dodec-4-ene, 9-cyclopentenyltetracyclo [6.2.1.13,6.02,7] dodeca Non-polar tetracyclododecenes such as -4-ene, 9-phenyltetracyclo [6.2.1.13, 6.02,7] dodec-4-ene;

  2-norbornene, 5-methyl-2-norbornene, 5-ethyl-2-norbornene, 5-butyl-2-norbornene, 5-hexyl-2-norbornene, 5-decyl-2-norbornene, 5-cyclohexyl-2- Norbornene, 5-cyclopentyl-2-norbornene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-propenyl-2-norbornene, 5-cyclohexenyl-2-norbornene, 5-cyclopentenyl-2- Norbornene, 5-phenyl-2-norbornene, tetracyclo [9.2.1.02,10.03,8] tetradeca-3,5,7,12-tetraene (1,4-methano-1,4,4a, 9a-tetrahydro-9H-fluorene.), Tetracyclo [10.2.1.02, 11. 4,9] pentadeca -4,6,8,13- tetraene (. 1,4-methano -1,4,4a, 9, 9a, also referred to as 10-hexa hydro anthracene) nonpolar norbornene, such as;

  Pentacyclo [6.5.1.13,6.02,7.09,13] pentadeca-4,10-diene, pentacyclo [9.2.14,7.02, 10.03,8] pentadeca- Non-polar cyclic olefins having five or more pentacycles such as 5,12-diene, hexacyclo [6.6.1.13, 6.110, 13.02, 7.09,14] heptade-4-ene; It is.

  From the viewpoint of easy availability and improved heat resistance of the film, preferred nonpolar norbornene monomers are nonpolar dicyclopentadienes and nonpolar tetracyclododecenes, and more preferred nonpolar norbornene monomers are nonpolar dicyclones. Cyclopentadiene.

  Specific examples of the norbornene-based monomer containing a polar group include tetracyclo [6.2.13, 6.02,7] dodec-9-ene-4-carboxylate, tetracyclo [6.2.1.13, 6.02,7] dodec-9-ene-4-methanol, tetracyclo [6.2.13,6.02,7] dodec-9-ene-4-carboxylic acid, tetracyclo [6.2.1 .13,6.02,7] dodec-9-ene-4,5-dicarboxylic acid, tetracyclo [6.2.13,6.02,7] dodec-9-ene-4,5-dicarboxylic acid Anhydride, methyl 5-norbornene-2-carboxylate, methyl 2-methyl-5-norbornene-2-carboxylate, 5-norbornene-2-yl acetate, 5-norbornene-2-methanol, 5-norbornene-2- All, 5-norbornene 2-carbonitrile, 2-acetyl-5-norbornene, and the like 7-oxa-2-norbornene.

  Specific examples of the monocyclic olefin include cyclobutene, cyclopentene, cyclohexene, cyclooctene, cyclododecene, 1,5-cyclooctadiene, and derivatives thereof having a substituent.

  These (a) cyclic olefin monomers are used singly or in combination of two or more. The addition amount of the monocyclic olefin is preferably 40% by mass or less, more preferably 20% by mass or less, based on the total amount of the (a) cyclic olefin monomer. If the amount of monocyclic olefin added is too large, the heat resistance of the film may be insufficient.

 The polymerizable composition containing (a) a cyclic olefin monomer and (b) specific artificial graphite is subjected to ring-opening metathesis polymerization in the presence of a composition containing a polymerization catalyst. The polymerization catalyst (a) causes ring-opening metathesis polymerization of a cyclic olefin monomer. The polymerization catalyst is not limited to a specific catalyst.

  A complex formed by bonding a plurality of ions, atoms, polyatomic ions and / or compounds around a transition metal atom is used as a polymerization catalyst. Atoms of Group 5, Group 6, and Group 8 (long-period periodic table, the same applies hereinafter) are used as transition metal atoms. The atoms of each group are not particularly limited, but the preferred Group 5 atom is tantalum, the preferred Group 6 atom is molybdenum and tungsten, and the preferred Group 8 atom is ruthenium and osmium.

  A preferred metathesis polymerization catalyst is a complex of Group 8 ruthenium and osmium, and a particularly preferred metathesis polymerization catalyst is a ruthenium carbene complex. Since the ruthenium carbene complex is excellent in catalytic activity during bulk polymerization, a crosslinked cyclic olefin polymer with little residual unreacted monomer can be obtained with high productivity.

  Specific examples of the ruthenium carbene complex are complexes represented by the following formula (1) or (2) from the viewpoint of catalytic activity.

In the formulas (1) and (2), R ¹ and R ² each independently include a hydrogen atom; a halogen atom; or a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom. It represents a good cyclic or chain hydrocarbon group having 1 to 20 carbon atoms. X ¹ and X ² each independently represents an arbitrary anionic ligand. L ¹ and L ² each independently represents a neutral electron donating compound. R ¹ and R ² may be bonded to each other to contain a hetero atom, and may form an aliphatic ring or an aromatic ring. Furthermore, R ¹ , R ² , X ¹ , X ² , L ¹ and L ² may be bonded together in any combination to form a multidentate chelating ligand.

  The heteroatom in the present invention is an atom of Groups 15 and 16 of the periodic table. Specific examples of the hetero atom include a nitrogen atom (N), an oxygen atom (O), a phosphorus atom (P), a sulfur atom (S), an arsenic atom (As), and a selenium atom (Se). From the viewpoint of the stability of the carbene compound, preferred heteroatoms are N, O, P, and S, and particularly preferred heteroatoms are N.

  Neutral electron donating compounds are roughly classified into hetero atom-containing carbene compounds and other neutral electron donating compounds. From the viewpoint of the activity of the polymerization catalyst, preferred neutral electron donating compounds are heteroatom-containing carbene compounds. A heteroatom-containing carbene compound in which heteroatoms are adjacently bonded to both sides of the carbene carbon is preferable, and a heteroatom-containing carbene compound in which a heterocycle is formed including the carbene carbon atom and heteroatoms on both sides thereof is more preferable. preferable. The heteroatom adjacent to the carbene carbon preferably has a bulky substituent.

  Specific examples of preferred heteroatom-containing carbene compounds are compounds represented by the following formula (3) or formula (4).

In Formula (3) and Formula (4), R ^{3 to} R ⁶ may each independently contain a hydrogen atom; a halogen atom; or a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, or silicon atom. Represents a cyclic or chain hydrocarbon group having 1 to 20 carbon atoms. R ^{3 to} R ⁶ may be bonded to each other in any combination to form a ring.

  Specific examples of the compound represented by the formula (3) or the formula (4) include 1,3-dimesitylimidazolidin-2-ylidene and 1,3-di (1-adamantyl) imidazolidin-2-ylidene. 1-cyclohexyl-3-mesitylimidazolidine-2-ylidene, 1,3-dimesityloctahydrobenzimidazol-2-ylidene, 1,3-diisopropyl-4-imidazoline-2-ylidene, 1,3- And di (1-phenylethyl) -4-imidazoline-2-ylidene and 1,3-dimesityl-2,3-dihydrobenzimidazol-2-ylidene.

  In addition to the compound represented by the formula (3) or (4), 1,3,4-triphenyl-2,3,4,5-tetrahydro-1H-1,2,4-triazole-5-ylidene 1,3-dicyclohexylhexahydropyrimidin-2-ylidene, N, N, N ′, N′-tetraisopropylformamidinylidene, 1,3,4-triphenyl-4,5-dihydro-1H-1, Heteroatom-containing carbene compounds such as 2,4-triazole-5-ylidene and 3- (2,6-diisopropylphenyl) -2,3-dihydrothiazol-2-ylidene can be used.

  Neutral electron donating compounds other than heteroatom-containing carbene compounds are ligands that have a neutral charge when pulled away from the central metal. Specific examples of the neutral electron donating compound include carbonyls, amines, pyridines, ethers, nitriles, esters, phosphines, thioethers, aromatic compounds, olefins, isocyanides, thiocyanates, and the like. is there. Preferred neutral electron donating compounds are phosphines, ethers and pyridines, and a more preferred neutral electron donating compound is trialkylphosphine.

In the formulas (1) and (2), the anionic (anionic) ligands X ¹ and X ² are ligands having a negative charge when separated from the central metal atom. Examples are halogen atoms such as fluorine atom (F), chlorine atom (Cl), bromine atom (Br), iodine atom (I), diketonate group, substituted cyclopentadienyl group, alkoxy group, aryloxy group, carboxyl group Etc. A preferred anionic ligand is a halogen atom, and a more preferred ligand is a chlorine atom.

In the above formula (1), an example of a ruthenium carbene complex in which X ² and L ² are bonded to each other to form a multidentate chelating ligand is a Schiff base coordination complex represented by the following formula (5) It is.

In the formula (5), Z represents an oxygen atom, a sulfur atom, a selenium atom, NR ¹² , PR ¹² or AsR ¹² , and R ¹² is the same as those exemplified for R ¹ and R ² .

In Formula (5), R ^{7 to} R ⁹ each independently represent a monovalent organic group that may contain a hydrogen atom, a halogen atom, or a hetero atom. Specific examples of the monovalent organic group that may contain a hetero atom include an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aryl group, and a carbon number. An alkoxyl group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, an alkynyloxy group having 2 to 20 carbon atoms, an aryloxy group, an alkylthio group having 1 to 8 carbon atoms, a carbonyloxy group having 1 to 20 carbon atoms, C1-C20 alkoxycarbonyl group, C1-C20 alkylsulfonyl group, C1-C20 alkylsulfinyl group, C1-C20 alkyl sulfonic acid group, aryl sulfonic acid group, C1-C1 20 phosphonic acid groups, arylphosphonic acid groups, alkylammonium groups having 1 to 20 carbon atoms, arylammonium groups, and the like.
The monovalent organic group which may contain these heteroatoms may have a substituent and may be bonded to each other to form a ring. Examples of the substituent are an alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, and an aryl group. When the monovalent organic group forms a ring, the ring may be an aromatic ring, an alicyclic ring, or a heterocyclic ring.

In formula (5), R ¹⁰ and R ¹¹ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a heteroaryl group, and these groups are May have a substituent and may be bonded to each other to form a ring. Examples of the substituent are an alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, and an aryl group. When R ¹⁰ and R ¹¹ form a ring, the ring may be an aromatic ring, an alicyclic ring, or a heterocyclic ring.

  Specific examples of the complex compound represented by the formula (1) include benzylidene (1,3-dimesityl-4-imidazolidin-2-ylidene) (tricyclohexylphosphine) ruthenium dichloride, benzylidene (1,3-dimesityl-4). , 5-Dibromo-4-imidazoline-2-ylidene) (tricyclohexylphosphine) ruthenium dichloride, (1,3-dimesityl-4-imidazoline-2-ylidene) (3-phenyl-1H-indene-1-ylidene) ( Tricyclohexylphosphine) ruthenium dichloride, (1,3-dimesityl-4-imidazolidin-2-ylidene) (3-methyl-2-buten-1-ylidene) (tricyclopentylphosphine) ruthenium dichloride, benzylidene (1,3- Dimesityl-octahydrobenzimida 2-ylidene) (tricyclohexylphosphine) ruthenium dichloride, benzylidene [1,3-di (1-phenylethyl) -4-imidazoline-2-ylidene] (tricyclohexylphosphine) ruthenium dichloride, benzylidene (1,3 -Dimesityl-2,3-dihydrobenzimidazol-2-ylidene) (tricyclohexylphosphine) ruthenium dichloride, benzylidene (tricyclohexylphosphine) (1,3,4-triphenyl-2,3,4,5-tetrahydro-1H -1,2,4-triazole-5-ylidene) ruthenium dichloride, (1,3-diisopropylhexahydropyrimidin-2-ylidene) (ethoxymethylene) (tricyclohexylphosphine) ruthenium dichloride, benzylidene 1,3-dimesityl-4-imidazolidin-2-ylidene) pyridine ruthenium dichloride, (1,3-dimesityl-4-imidazolidin-2-ylidene) (2-phenylethylidene) (tricyclohexylphosphine) ruthenium dichloride, 1,3-Dimesityl-4-imidazoline-2-ylidene) (2-phenylethylidene) (tricyclohexylphosphine) ruthenium dichloride, (1,3-dimesityl-4,5-dibromo-4-imidazoline-2-ylidene) [ (Phenylthio) methylene] (tricyclohexylphosphine) ruthenium dichloride, (1,3-dimesityl-4,5-dibromo-4-imidazoline-2-ylidene) (2-pyrrolidone-1-ylmethylene) (tricyclohexylphosphine) ruthenium dichloride Lori A ruthenium complex compound in which one hetero atom-containing carbene compound and one neutral electron donating compound are bonded, such as

  A ruthenium complex compound in which two neutral electron-donating compounds are bonded, such as benzylidenebis (tricyclohexylphosphine) ruthenium dichloride, (3-methyl-2-buten-1-ylidene) bis (tricyclopentylphosphine) ruthenium dichloride;

  Two heteroatom-containing carbene compounds such as benzylidenebis (1,3-dicyclohexyl-4-imidazolidin-2-ylidene) ruthenium dichloride and benzylidenebis (1,3-diisopropyl-4-imidazoline-2-ylidene) ruthenium dichloride Ruthenium complex compound in which is bonded;

A ruthenium carbene complex represented by formula (6) in which X ² and L ² are bonded to each other to form a multidentate chelating ligand;

In the formula (6), Mes represents a mesityl group. R ⁷ and R ⁸ are each a hydrogen atom or a methyl group, and at least one of them is a methyl group. R ¹³ and R ¹⁴ each independently represents a monovalent organic group that may contain a hydrogen atom, a halogen atom, or a hetero atom. The “monovalent organic group” is the same as R ^{7 to} R ⁹ described above in the description of the formula (5).

  Specific examples of the complex compound represented by the formula (2) are (1,3-dimesityl-4-imidazolidin-2-ylidene) (phenylvinylidene) (tricyclohexylphosphine) ruthenium dichloride, (t-butylvinylidene). (1,3-diisopropyl-4-imidazoline-2-ylidene) (tricyclopentylphosphine) ruthenium dichloride, bis (1,3-dicyclohexyl-4-imidazoline-2-ylidene) phenylvinylidene ruthenium dichloride, and the like.

  The most preferable complex compound has one compound represented by the formula (1) and represented by the formula (3) or (4) as a ligand.

  These ruthenium carbene complexes are described in (a) Org. Lett. 1999, Vol. 1, p. 953, (b) Tetrahedron. Lett. 1999, 40, 2247, (c) International Publication No. 2003/062253, and the like.

  The amount of the polymerization catalyst used is a molar ratio of (metal atom in the polymerization catalyst: (a) cyclic olefin monomer) and is usually 1: 2,000 to 1: 2,000,000, preferably 1: 5,000 to The range is from 1: 1,000,000, more preferably from 1: 10,000 to 1: 500,000. If the amount of the polymerization catalyst is too small, the polymerization reaction rate may decrease and monomers may remain in the polymer, or the crosslinking degree of the crosslinked polymer may decrease and the heat resistance of the resulting film may decrease. is there. If the amount of the polymerization catalyst is too large, the production cost increases, and the reaction rate becomes too fast, which may make it difficult to form a film during bulk polymerization, which will be described later.

The polymerization catalyst can be used in combination with an activator (cocatalyst) for the purpose of controlling the polymerization activity and improving the polymerization reaction rate. Specific examples of the activator include aluminum, scandium, tin, silicon alkylates, halides, alkoxylates and aryloxylates. Further specific examples of activators include aluminum compounds such as trialkoxyaluminum, triphenoxyaluminum, dialkoxyalkylaluminum, alkoxydialkylaluminum, trialkylaluminum, dialkoxyaluminum chloride, alkoxyalkylaluminum chloride, dialkylaluminum chloride; trialkoxy Scandium compounds such as scandium; titanium compounds such as tetraalkoxy titanium; tin compounds such as tetraalkyls and tetraalkoxytin; zirconium compounds such as tetraalkoxyzirconium; dimethylmonochlorosilane, dimethyldichlorosilane, diphenyldichlorosilane, tetrachlorosilane, bicyclo Heptenylmethyldichlorosilane, phenylmethyldichlorosilane, Hexyl dichlorosilane, phenyl trichlorosilane, silane compounds such as methyltrichlorosilane or the like.
The use amount of the activator is usually 1: 0.05 to 1: 100, preferably 1: 0.2 to 1:20, more preferably, in a molar ratio of (metal atom in the polymerization catalyst: activator). The range is 1: 0.5 to 1:10.

  The polymerization catalyst can be used in combination with a polymerization regulator for the purpose of controlling the polymerization activity and adjusting the polymerization reaction rate. Specific examples of the polymerization regulator include triphenylphosphine, tricyclohexylphosphine, tributylphosphine, 1,1-bis (diphenylphosphino) methane, 1,4-bis (diphenylphosphino) butane, 1,5-bis (diphenyl). Phosphino) phosphorus compounds such as pentane; Lewis bases such as ethers, esters and nitriles. The amount of these used is usually 0.01 to 50 mol, preferably 0.05 to 10 mol, relative to 1 mol of the polymerization catalyst.

  The method for producing a conductive thermosetting film of the present invention may be either a solution polymerization method or a bulk polymerization method, but does not require a solvent removal step, and when a resin composition molded into a film shape at the same time as polymerization can be obtained. In view of the above, the bulk polymerization method is preferable.

In the bulk polymerization method, a polymerizable composition containing (a) a cyclic olefin monomer and (b) specific artificial graphite is subjected to ring-opening metathesis polymerization in the presence of a polymerization catalyst and an additive used as necessary, to form a film shape. The process of shape | molding is included.
(A) The cyclic olefin monomer is subjected to ring-opening metathesis polymerization to obtain a cyclic olefin polymer, and the cyclic olefin polymer is crosslinked after the ring-opening metathesis polymerization or simultaneously with the ring-opening metathesis polymerization. It is believed that a polymer is obtained.

  The three-dimensional crosslinked structure of the cyclic olefin polymer is confirmed by the solubility in 1,2-dichlorobenzene. When the cyclic olefin polymer is immersed in 1,2-dichlorobenzene at 23 ° C. for 24 hours and the resulting solution is filtered through an 80-mesh wire mesh, the degree of crosslinking expressed by insoluble matter is preferably 70% by mass or more. More preferably, it is 80 mass% or more, More preferably, it is 85 mass% or more. If the degree of crosslinking is too low, the desired flexibility will not be exhibited, and the uncrosslinked component may contaminate the member used with the conductive thermosetting film.

  The conductive thermosetting film of the present invention contains (b) artificial graphite. (B) The pH of the artificial graphite aqueous dispersion is 7.0 or more. If the pH of the artificial graphite aqueous dispersion is too low, (a) the ring-opening metathesis polymerization of the cyclic olefin monomer does not proceed, and a conductive thermosetting film may not be formed.

  (B) The average particle diameter of the artificial graphite is 4.5 to 15 μm. If the average particle size of the artificial graphite is too small, (a) the ring-opening metathesis polymerization of the cyclic olefin monomer does not proceed, and there is a possibility that a conductive thermosetting film cannot be formed. When the average particle diameter of artificial graphite is too large, the electroconductivity of a conductive thermosetting film will fall.

  Here, “average particle diameter” means that measured by the method described below. That is, it means that measured by a laser type particle size measuring machine (manufactured by Seishin Enterprise Co., Ltd.) by a micro-sorting control method (a method in which measurement target particles are allowed to pass only in the measurement region and the measurement reliability is improved). . According to this measurement method, by passing 0.01 g to 0.02 g of measurement target particles through the cell, the measurement target particles flowing into the measurement region are irradiated with semiconductor laser light having a wavelength of 670 nm, and the laser at that time By measuring light scattering and diffraction with a measuring instrument, the average particle size and particle size distribution can be calculated from the Franhofer diffraction principle.

The said polymerizable composition contains 50-200 mass parts (b) artificial graphite with respect to 100 mass parts (a) cyclic olefin monomer. (B) When the content rate of artificial graphite is too low, the electroconductivity of a conductive thermosetting film will fall. (B) When the content ratio of the artificial graphite is too high, the flexibility of the conductive thermosetting film is lowered.
The (b) artificial graphite is commercially available, and a specific example thereof is SGO-5 manufactured by SEC Carbon Co., Ltd.

  Various additives can be incorporated into the conductive thermosetting film of the present invention for the purpose of improving the properties of the film according to various uses and purposes, imparting functions, and improving the workability of molding. Specific examples of such additives include antioxidants, (b) fillers other than artificial graphite, antifoaming agents, foaming agents, colorants, ultraviolet absorbers, light stabilizers, flame retardants, wetting agents, Dispersants, release lubricants, plasticizers and the like. Preferably, an antioxidant is contained in order to improve the durability and storage stability of the crosslinked cyclic olefin polymer.

  Specific examples of the antioxidant include quinones such as parabenzoquinone, tolquinone and naphthoquinone; hydroquinones such as hydroquinone, para-t-butylcatechol and 2,5-di-t-butylhydroquinone; di-t-butyl para Phenols such as cresol, hydroquinone monomethyl ether and pyrogallol; copper salts such as copper naphthenate and copper octenoate; quaternary ammonium salts such as trimethylbenzylammonium chloride, trimethylbenzylammonium maleate and phenyltrimethylammonium chloride; quinonedioxime And oximes such as methyl ethyl ketoxime; amine hydrochlorides such as triethylamine hydrochloride and dibutylamine hydrochloride. The kind and amount of these antioxidants are appropriately selected depending on conditions such as mechanical properties at high temperature, film forming workability, and storage stability of the crosslinked cyclic olefin polymer. Phenols are preferred because they have high compatibility with the crosslinked cyclic olefin polymer, are uniformly dispersed, and improve the durability and storage stability of the film. One or more antioxidants are used in combination. The usage-amount of antioxidant is 10 mass parts or less normally with respect to 100 mass parts of (a) cyclic olefin monomer.

(B) Specific examples of fillers other than artificial graphite include inorganic fillers such as carbon black, natural graphite, silica, silica sand, glass powder, calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay; wood powder, polyester beads Organic fillers such as polystyrene beads. The filler improves physical properties such as shrinkage rate, elastic modulus, thermal conductivity, and conductivity of the crosslinked cyclic olefin polymer.
Grades such as the particle size, shape, aspect ratio, and quality of the filler are appropriately determined depending on the physical properties of the crosslinked cyclic olefin polymer. The amount of these fillers to be used is preferably 400 parts by mass or less, more preferably 300 parts by mass or less, relative to 100 parts by mass of (a) the cyclic olefin monomer.

  Specific examples of the release lubricant include silicone oil and zinc stearate. The mold release lubricant improves the moldability, mold release and handling properties of the film and imparts functions such as lubricant properties to the film. The amount of the release lubricant used is preferably 200 parts by mass or less with respect to 100 parts by mass of the (a) cyclic olefin monomer.

  A polymerizable composition containing (a) a cyclic olefin monomer and (b) artificial graphite is subjected to ring-opening metathesis polymerization in the presence of a composition containing a polymerization catalyst and additives used as necessary. The polymerization catalyst is used after being dissolved or suspended in a small amount of an inert solvent, if necessary. Specific examples of the solvent include chain aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane, liquid paraffin, and mineral spirits; cyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, trimethylcyclohexane, ethylcyclohexane, Alicyclic hydrocarbons such as diethylcyclohexane, decahydronaphthalene, dicycloheptane, tricyclodecane, hexahydroindene and cyclooctane; aromatic hydrocarbons such as benzene, toluene and xylene; and alicyclic rings such as indene and tetrahydronaphthalene Hydrocarbons having an aromatic ring; nitrogen-containing hydrocarbons such as nitromethane, nitrobenzene, and acetonitrile; oxygen-containing hydrocarbons such as diethyl ether and tetrahydrofuran. Preferred solvents are aromatic hydrocarbons, aliphatic hydrocarbons, alicyclic hydrocarbons, and hydrocarbons having an alicyclic ring and an aromatic ring. You may use the liquid anti-aging agent or plasticizer which does not reduce the activity as a polymerization catalyst as a solvent.

  The viscosity at room temperature of the composition containing (a) a cyclic olefin monomer, (b) artificial graphite and an additive used as necessary depends on the desired film thickness, but is preferably 3 to 500 Pa · s. It becomes easy to form in a film shape because a viscosity exists in said preferable range. The viscosity of the composition is adjusted by the type and amount of (a) cyclic olefin monomer and (b) artificial graphite.

  Specific examples of the method of bulk polymerization of the above composition into a film shape include a method of bulk polymerization by sandwiching the above composition between two supports, and bulk polymerization by pouring or applying the above composition onto a support. A method of bulk polymerization of the above composition in a mold. The method of bulk polymerization by sandwiching the composition between two supports is more preferable because a thin and uniform film can be produced with high accuracy in thickness. More preferably, the composition is sandwiched between two supports, passed between two rolls having a predetermined gap, and then bulk polymerized.

  General known materials such as resin, glass and metal are selected as the support. Specific examples of the resin include polyesters such as polyethylene terephthalate, polyethylene naphthalate, and polyarylate; polycarbonates; polyolefins such as polypropylene and polyethylene; polyamides such as nylon; fluororesins such as polytetrafluoroethylene; Is preferred. A preferable shape of the support is a drum or a belt if the material is metal or resin. A preferred support is a resin film that is easily available and inexpensive.

  The composition is subjected to bulk polymerization by heating to a temperature at which the polymerization catalyst exhibits activity, if necessary. The polymerization temperature is usually 0 to 250 ° C, preferably 20 to 200 ° C. The method for heating the composition is not particularly limited. Specific examples of the heating method include a method of heating on a heating plate, a method of heating (hot pressing) while applying pressure using a press, a method of pressing with a heated roller, and a method of using a heating furnace. The polymerization reaction time is appropriately determined depending on the amount of the polymerization catalyst and the heating temperature, but is usually 1 minute to 24 hours.

 The cyclic olefin polymer is crosslinked. Crosslinking is performed after polymerization or simultaneously with polymerization. Crosslinking performed simultaneously with the polymerization is more preferable because the conductive thermosetting film of the present invention can be obtained industrially advantageously with fewer steps.

  Specific examples of the crosslinking method include: (A) (a) a method in which a crosslinkable monomer is used as at least a part of the cyclic olefin monomer and polymerized to obtain a polymer having a three-dimensional crosslinked structure; (B) the above composition A bulk polymerization is carried out by adding a crosslinking agent to the polymer, and a crosslinking reaction is carried out by carrying out a crosslinking reaction simultaneously with or after the polymerization; (C) a cyclic olefin polymer is irradiated with light or an electron beam, and a crosslinking reaction is carried out after the polymerization. Cross-linking method; One of these methods may be used, or two or more methods may be used in combination. The method (A) is preferable from the viewpoint of easy control of physical properties of the film and economical efficiency.

  The (a) cyclic olefin monomer having two or more carbon-carbon double bonds is used as the crosslinkable monomer used in the method (A). Specific examples of the cyclic olefin monomer are dicyclopentadiene and tricyclopentadiene. The crosslinking density can be controlled by the amount of the crosslinking monomer used and the heating temperature during polymerization. The amount of the crosslinkable monomer used is not particularly limited because appropriate crosslink density varies depending on the use of the film. A preferable use amount of the crosslinkable monomer is 0.1 to 100 mol% in terms of the crosslinkable monomer in the total amount of the cyclic olefin monomer.

  A known thermal crosslinking agent and photocrosslinking agent are used as the crosslinking agent used in the method (B). Preferred thermal crosslinking agents are radical generators such as organic peroxides, diazo compounds, and nonpolar radical generators. The amount of the crosslinking agent to be used is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass with respect to 100 parts by mass of (a) the cyclic olefin monomer. The temperature at which crosslinking is performed when a thermal crosslinking agent is used is usually 100 to 250 ° C, preferably 150 to 200 ° C. The time for crosslinking is not particularly limited, but is usually from several minutes to several hours.

  The bulk polymerization and crosslinking in the present invention are preferably performed in the absence of oxygen and water. Specific examples of the bulk polymerization and crosslinking method include (1) a method of bulk polymerization and crosslinking in an inert gas atmosphere such as nitrogen gas and argon gas, and (2) a method of bulk polymerization and crosslinking under vacuum, (3 ) Bulk polymerization and crosslinking in a state where the composition coated on the support is covered with a resin film and sealed. Specific examples of the resin film are those exemplified as the support. When bulk polymerization and crosslinking are performed in the presence of oxygen or water, the surface of the resulting film may be oxidized, making it difficult to exhibit desired flexibility.

  The thickness of the conductive thermosetting film of the present invention has various appropriate values depending on the application and is not particularly limited, but is usually 0.5 to 5,000 μm, which is preferable from the viewpoint of handling properties. The thickness is 5 to 500 μm. The surface of the conductive thermosetting film of the present invention may be smooth, but may have an uneven shape formed by embossing.

  The conductive heat of the present invention is applied to a layer made of a different material such as an organic material, an inorganic material, or a metal by using a known surface treatment technology such as gas phase reaction, coating, vacuum deposition, ion plating, sputtering, CVD, electroless plating. You may form in the cured film surface. For example, a thin film made of a material that improves conductivity, such as a conductive inorganic compound or metal, can be provided on the film surface layer.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited to these Examples. Unless otherwise indicated, the part and% in an Example and a comparative example are a mass reference | standard.

Various physical properties were measured as follows.
(1) pH of graphite or carbon black aqueous dispersion
About 0.5 g of various types of graphite or carbon black was dispersed in 50 ml of ion exchange water, and the pH of the obtained dispersion was measured at 23 ° C. with a pH meter (D-51T manufactured by Horiba, Ltd.).

(2) Volume resistivity of film A film having a thickness of about 50 μm is cut into a size of 5 cm × 5 cm, and a surface resistance value (Ω) is measured at 23 ° C. using a resistance meter (Miliohm Hitester 3540 manufactured by Hioki Electric Co., Ltd.). Measured with The volume resistivity value was calculated from the surface resistance value and the film thickness according to the following formula.
Volume resistivity (Ω · cm) = Surface resistance (Ω) x Film thickness (cm)
The smaller the volume resistivity value, the higher the conductivity.

(3) Flexibility of film A film having a thickness of about 50 μm was cut into a size of 10 cm × 2 cm, had both ends in the longitudinal direction, bent 180 degrees at 23 ° C., returned to its original state, and evaluated as follows.
A: The film was not deformed and did not break.
B: The film was deformed or broken.
When evaluation is A, it is excellent in the flexibility of a film.

Examples 1 and 2 and Comparative Examples 1-8
The types and masses of graphite or carbon black shown in Table 1 were dispersed in dicyclopentadiene at 23 ° C. using a mortar to obtain a reaction stock solution. Next, a ruthenium catalyst having a structure represented by the following formula (7) was added to the reaction stock solution and mixed in a mortar to obtain a polymerizable composition. The polymerizable composition was sandwiched between two polyethylene terephthalate carrier films having a thickness of 50 μm and passed between two rolls having a gap of 150 μm. Then, it heated at 150 degreeC for 5 minute (s), and the electroconductive thermosetting film was obtained. However, in Comparative Example 3, Comparative Example 6, and Comparative Example 8, a film could not be obtained. The results are shown in Table 1.

1) VC843 manufactured by RIMTEC Corporation
2) SGO-5 manufactured by SEC Carbon Co., Ltd. (average particle size 5 μm)
3) SGL-4 (average particle diameter: 4 μm) manufactured by SEC Carbon Co., Ltd.
4) SGO-20 manufactured by SEC Carbon Co., Ltd. (average particle size 20 μm)
5) Denka Black (average particle size: 0.03 μm) manufactured by Denki Kagaku Kogyo Co., Ltd.
6) CSP2 manufactured by Fuji Graphite Industry Co., Ltd. (average particle size 74 μm)

The volume specific resistance values of the conductive thermosetting films of Examples 1 and 2 were small, and these films were not brittle.
The volume specific resistance value of the conductive thermosetting film of Comparative Example 1 in which the content of artificial graphite was too small was large. The volume specific resistance value of the conductive thermosetting film of Comparative Example 2 in which the content of artificial graphite was too large was large, and the film was brittle. The ring-opening metathesis polymerization of the polymerizable composition of Comparative Example 3 did not occur when the pH of the artificial graphite aqueous dispersion was lower than 7.0 and the average particle size of the artificial graphite was too small. The volume specific resistance value of the conductive thermosetting film of Comparative Example 4 in which the average particle diameter of the artificial graphite was too large was large. The volume specific resistance value of the conductive thermosetting film of Comparative Example 5 containing no artificial graphite and containing carbon black was large. Furthermore, the polymerizable composition of Comparative Example 6 containing more carbon black was powdery and could not be formed. The volume specific resistance value of the conductive thermosetting film of Comparative Example 7 containing no artificial graphite and containing natural graphite having a large average particle diameter was large. Furthermore, the polymerizable composition of Comparative Example 8 containing a large amount of natural graphite was powdery and could not be formed.

  The conductive thermosetting film of the present invention has a small volume resistivity value. Therefore, the electroconductive thermosetting film of this invention is used for the use as which high electroconductivity is requested | required.

Claims (6)

Obtained by ring-opening metathesis polymerization of a polymerizable composition containing (a) 100 parts by mass of a cyclic olefin monomer and (b) 50 to 200 parts by mass of artificial graphite,
The conductive thermosetting film in which the pH of the (b) artificial graphite aqueous dispersion is 7.0 or more, and the average particle diameter of the (b) artificial graphite is 4.5 to 15 μm.   The conductive thermosetting film according to claim 1, wherein the (a) cyclic olefin monomer is a norbornene-based monomer. Including a step of ring-opening metathesis polymerization of a polymerizable composition containing (a) 100 parts by mass of a cyclic olefin monomer and (b) 50 to 200 parts by mass of artificial graphite in the presence of a composition containing a polymerization catalyst,
The conductive heat according to claim 1, wherein the pH of the aqueous dispersion of (b) artificial graphite is 7.0 or more, and the average particle size of (b) artificial graphite is 4.5 to 15 µm. A method for producing a cured film.   The method for producing a conductive thermosetting film according to claim 3, wherein the (a) cyclic olefin monomer is a norbornene-based monomer.   The conductivity according to claim 3 or 4, wherein the composition comprising the polymerizable composition and the polymerization catalyst is sandwiched between two supports, and ring-opening metathesis polymerization is performed between the two supports. A method for producing a thermosetting film.   The method for producing a conductive thermosetting film according to any one of claims 3 to 5, wherein the polymerization catalyst is a ruthenium carbene complex.