JP5552904B2 - Method for producing nanocarbon-containing fiber and nanocarbon structure fiber, and nanocarbon-containing fiber and nanocarbon structure fiber obtained by these methods - Google Patents

Description

  The present invention relates to a method for producing nanocarbon-containing fibers and nanocarbon structure fibers, and nanocarbon-containing fibers and nanocarbon structure fibers obtained by these methods.

  A composition comprising a carbon nanotube which is a nanocarbon material, a water-soluble conductive polymer and a solvent, and a composite (conductor) produced from the composition are known (Patent Document 1). In the composition and composite, by coexisting a water-soluble conductive polymer, the carbon nanotubes are dispersed or solubilized in a solvent such as water, an organic solvent, or a water-containing organic solvent without impairing the characteristics of the carbon nanotubes themselves. It is excellent in long-term storage stability.

  It has been reported that a carbon nanotube-containing fiber can be obtained by wet spinning by extruding a carbon nanotube-containing composition in which these water-soluble conductive polymers coexist in a coagulation bath and drawing (Patent Document 2). Since this fiber is a conventional wet spinning method, the diameter of the single fiber is several tens of microns or more, and when used as an electrode material for battery materials, there is a problem that the specific surface area is small and sufficient characteristics cannot be exhibited. In addition to the carbon nanotubes, a water-soluble conductive polymer that is a dispersant and a polymer compound that is a binder polymer coexist, so that there is a problem that the properties such as the conductivity of the carbon nanotubes cannot be fully exhibited.

  Also reported is a carbon fiber obtained by discharging and solidifying a spinning yarn composed of carbon nanofibers, a dispersant, an acrylonitrile-based polymer and a solvent from a spinneret and then firing the acrylic fiber. (Patent Document 3). Since this carbon fiber is also a conventional spinning method, the single fiber diameter is several microns or more, and in addition to the carbon nanotube, a water-soluble conductive polymer as a dispersant and an acrylonitrile polymer as a binder polymer coexist. There is a problem that the above characteristics cannot be fully exhibited.

  On the other hand, a method for producing nanofibers containing carbon nanotubes by dispersing a single-walled carbon nanotube in dimethylformamide, adding polyacrylonitrile to prepare a spinning solution, and electrospinning the solution is reported. . Furthermore, it has been reported that nano-sized carbon fibers are produced by heat-treating the nano-fibers (Non-patent Document 1). However, it is difficult to say that single-walled carbon nanotubes are sufficiently dispersed because they are simply stirred in dimethylformamide. Moreover, since the polyacrylonitrile is graphitized in the heat treatment, there is a problem that the graphitized crystal remains and the characteristics of the single-walled carbon nanotube itself are not exhibited.

International Publication No. 2004/039893 Pamphlet JP 2005-105510 A JP 2006-200114 A

Hoa Lam, Polymer Preprints 2003, 44 (2), 156

  When manufacturing the fiber containing a carbon nanotube, it is necessary to contain a binder polymer in the solution for spinning. However, in that case, the carbon nanotubes are covered with a binder polymer that is an insulator, and the carbon nanotubes cannot exhibit their original properties such as conductivity. In addition, since the fiber diameter is several microns or more due to the wet spinning method, there is a problem that the specific surface area is small and the method cannot be applied to battery electrode materials.

  The present invention has been made in view of the above circumstances, and without damaging the properties of the nanocarbon material itself such as carbon nanotubes, the nanocarbon material is oriented in the longitudinal direction of the fiber and has excellent conductivity. It aims at providing the manufacturing method of the nano carbon containing fiber provided with property, and the nano carbon structure fiber obtained from it.

  As a result of diligent research to solve these problems, the inventor conducted electrospinning using a nanocarbon-containing composition in which a conductive polymer, nanocarbon, a solvent, and a polymer compound coexisted, thereby obtaining a fiber diameter. It has been found that nano-level nanocarbon-containing fibers are obtained, and further, by firing the nanocarbon-containing fibers, nanocarbon structure fibers substantially composed of the nanocarbon material itself are obtained.

That is, the first of the present invention is a nanocarbon-containing material containing a conductive polymer (A), a nanocarbon material (B), a solvent (C), and a polymer compound (D) different from the conductive polymer (A). A method for producing nanocarbon-containing fibers by electrospinning a composition.
In addition, spinnability can be improved by adding a basic compound to the nanocarbon-containing composition.

  The second of the present invention is a method for producing a nanocarbon structure fiber in which the conductive polymer (A) and the polymer compound (D) are burned out by heating the nanocarbon-containing fiber.

  A third aspect of the present invention is a sheet-like or twisted structure made of nanocarbon-containing fibers produced by the first method of the present invention.

  A fourth aspect of the present invention is a sheet-like or twisted-like structure composed of nanocarbon structure fibers produced by the second method of the present invention.

  The nanocarbon-containing fiber produced by the method of the present invention and the nanocarbon structure fiber obtained therefrom can be arbitrarily adjusted by controlling the spinning conditions from the nanometer level to the micron level. In particular, when the fiber diameter is at the nano level, the specific surface area is large, and it has excellent conductivity without impairing the properties of the nano carbon material itself.

2 is a SEM photograph of a sheet-like structure composed of nanocarbon-containing fibers obtained in Example 1. 2 is a SEM photograph of an array fiber composed of nanocarbon-containing fibers obtained in Example 1. 2 is a SEM photograph of a twisted-like structure composed of nanocarbon-containing fibers obtained in Example 1. 3 is a TEM photograph of nanocarbon-containing fibers obtained in Example 1. FIG. 3 is a SEM photograph of a sheet-like structure made of fibers obtained in Comparative Example 1. 4 is a SEM photograph of a sheet-like structure made of nanocarbon-containing fibers obtained in Example 3. 4 is a SEM photograph of a twisted-like structure composed of nanocarbon-containing fibers obtained in Example 4.

  Details of the present invention will be described below.

<Nanocarbon-containing composition>
[Conductive polymer (A)]
The conductive polymer (A) is a conductive polymer having an acidic group such as a sulfonic acid group and / or a carboxy group. The conductive polymer (A) improves the solubility and dispersibility of the nanocarbon material (B), and makes it a stable nanomaterial-containing composition, resulting in the transparency and conductivity of the resulting fiber and nonwoven fabric. It plays a role to further improve.

  As the conductive polymer (A), a π-conjugated polymer containing phenylene vinylene, vinylene, thienylene, pyrrolylene, phenylene, iminophenylene, isothianaphthene, furylene, carbazolylene, or the like as a repeating unit can be used. Among these, a conductive polymer having a skeleton containing thienylene, pyrrolylene, iminophenylene, phenylene vinylene, carbazolylene, and isothianaphthene is particularly preferable.

  The conductive polymer (A) can be used as a π-conjugated conductive polymer having an acidic group or a salt thereof from the viewpoints of solubility, conductivity, film formability, etc., and is preferably used as the former. Here, the conductive polymer (A) having an acidic group may be an acidic group, an alkyl group substituted with an acidic group, or an acidic group on the skeleton of a π-conjugated polymer or a nitrogen atom in the polymer. Examples thereof include a substituted conductive polymer having an alkyl group containing an ether bond.

In addition, as a salt of the conductive polymer (A), by reacting the conductive polymer (A) with ammonium salts and / or amines, an acidic group is converted to an ammonium salt of a sulfonic acid group (—SO ₃ ⁻ M ⁺ ). And / or an ammonium salt of a carboxy group (—COO ^— M ⁺ ) can be used. Here, the ammonium ion (M ⁺ ) of the ammonium salt is represented by the following general formula (1).

(In the formula (1), R ^{1 to} R ⁴ are each independently hydrogen, alkyl having 1 to 24 carbon atoms, aryl or aralkyl group, phenyl group, benzyl group, R ⁵ OH, CONH ₂ or NH ₂ ; ^At least one of ^{1 to} R ⁴ is a group having 5 or more carbon atoms, wherein R ⁵ is an alkylene, arylene or aralkylene group having 1 to 24 carbon atoms.

  Examples of the conductive polymer (A) include JP-A 61-197633, JP-A 63-39916, JP-A 01-301714, JP-A 05-504153, and JP-A 05-503953. JP, 04-32848, JP 04-328181, JP 06-145386, JP 06-56987, JP 05-226238, JP 05-17889, JP 06-293828, JP 07-118524, JP 06-32845, JP 06-87949, JP 06-256516, JP 07-41756, JP 07-48436, JP-A 04-268331, JP-A 09-59376, JP 20 0-172384, JP-A No. 06-49183, JP-was disclosed in JP-A-10-60108 water-soluble electroconductive polymer is preferably used.

  Moreover, as preferable electroconductive polymer (A), the electroconductivity which contains 20-100% of at least 1 or more types of repeating unit chosen from following General formula (2)-(10) in the total number of the repeating units of the whole polymer. A functional polymer.

(In the formula ^{(2), R 6, R} 7 each _{^{independently, H, -SO 3 -, -SO}} 3 - M +, -SO 3 H, -R 8 SO 3 -, -R 8 SO 3 - M _{^{+, -R 8 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 8) 2, -NHCOR 8, -OH, ^{-O -, -SR 8, -OR 8} , -OCOR 8, -NO 2, -COO - M +, -COOH, -R 8 COOH, -R 8 COO - M +, -COOR 8, -COR 8, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the above formula (1), R ⁸ is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, arylene or aralkylene group, and less of ^R 6, ^{R 7} Kutomo one is _{^{-SO 3 -, -SO 3 H,}} -R 8 SO 3 -, -R 8 SO 3 H, -COOH, -R 8 COOH, and _{^{-SO 3 M +, -R 8 SO}} 3 - M ^{+, -COO - M +, -R} 8 COO - is a group selected from the group consisting of ^{M +).}

(In the formula ^{(3), R 9, R} 10 are each _{^{independently, H, -SO 3 -, -SO}} 3 - M +, -SO 3 H, -R 11 SO 3 -, -R 11 SO 3 - M _{^{+, -R 11 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 11) 2, -NHCOR 11, -OH, ^{-O -, -SR 11, -OR 11} , -OCOR 11, -NO 2, -COO - M +, -COOH, -R 11 COOH, -R 11 COO - M +, -COOR 11, -COR 11, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the formula (1), and R ¹¹ is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, An arylene or aralkylene group And ^{R 9,} at least one of ^{R 10} is _{^{-SO 3 -, -SO 3 H,}} -R 11 SO 3 -, -R 11 SO 3 H, -COOH, -R 11 COOH, and _-SO ³ - ^{M + _{, -R 11 SO 3 - M +}} , -COO - M +, -R 11 COO - is a group selected from the group consisting of ^{M +).}

(In the formula ^{(4), R} 12 ~R ¹⁵ are each independently _{^{H, -SO 3 -, -SO 3}} - M +, -SO 3 H, -R 16 SO 3 -, -R 16 SO 3 - M + _{^{, -R 16 SO 3 H, -OCH}} 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 16) 2, -NHCOR 16, -OH, - ^{O -, -SR 16, -OR 16} , -OCOR 16, -NO 2, -COO - M +, -COOH, -R 16 COOH, -R 16 COO - M +, -COOR 16, -COR 16, - Selected from the group consisting of CHO and —CN, wherein M ⁺ is an ammonium ion represented by the formula (1), and R ¹⁶ is an alkyl, aryl or aralkyl group or alkylene or arylene having 1 to 24 carbon atoms. Or an aralkylene group And at least one of _-SO ³ of _{^{R 12 ~R 15 -, -SO 3}} H, -R 16 SO 3 -, -R 16 SO 3 H, -COOH, -R 16 COOH, and _-SO ³ - ^{M + _{, -R 16 SO 3 - + M}} , -COO - M +, -R 16 COO - as ^{M +} group selected from the group consisting of).

(In the formula ^{(5), R} 17 ~R ²¹ are each _{^{independently, H, -SO 3 -, -SO}} 3 - M +, -SO 3 H, -R 22 SO 3 -, -R 22 SO 3 - M _{^{+, -R 22 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 22) 2, -NHCOR 22, -OH, ^{-O -, -SR 22, -OR 22} , -OCOR 22, -NO 2, -COO - M +, -COOH, -R 22 COOH, -R 22 COO - M +, -COOR 22, -COR 22, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the above formula (1), R ²² is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, An arylene or aralkylene group And at least one of _-SO ³ of _{^{R 17 ~R 21 -, -SO 3}} H, -R 22 SO 3 -, -R 22 SO 3 H, -COOH, -R 22 COOH, and -SO ₃ ^- M _{^{+, -R 22 SO 3 - M}} +, -COO - M +, -R 22 COO - is a group selected from the group consisting of ^{M +).}

(In the formula ^{(6), R} 23 _{^{is, -SO 3 -, -SO 3 H}} , -R 24 SO 3 -, -R 24 SO 3 H, -COOH, -R 24 COOH, and _-SO ³ - ^{M + _{, -R 25 SO 3 - + M}} , -COO - M + and ^-R 25 ^COO - selected from the group consisting of ^{M +,} wherein, ^{M +} is an ammonium ion represented by the formula (1), R ²⁴ is an alkyl, aryl or aralkyl group having 1 to ²⁴ carbon atoms or an alkylene, arylene or aralkylene group, and R ²⁵ is an alkylene, arylene or aralkylene group having 1 to 24 carbon atoms.

(In the formula (7), R ^{26 to} R ³¹ are each independently H, —SO ₃ ^— , —SO ₃ ^— M ⁺ , —SO ₃ H, —R ³² SO ₃ ^— , —R ³² SO ₃ ^— M. _{^{+, -R 32 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 32) 2, -NHCOR 32, -OH, ^{-O -, -SR 32, -OR 32} , -OCOR 32, -NO 2, -COO - M +, -COOH, -R 32 COOH, -R 32 COO - M +, -COOR 32, -COR 32, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the formula (1), and R ³² is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, An arylene or aralkylene group And at least one of _-SO of _{^{R 26 ~R 31 3 -, -SO}} 3 H, -R 5 SO 3 -, -R 32 SO 3 H, -COOH, -R 32 COOH, and -SO ₃ ^- M _{^{+, -R 32 SO 3 - +}} M, -COO - M +, -R 32 COO - a ^{M +} group selected from the group consisting of, Ht ^consists NR 33, S, O, Se and Te A heteroatom group selected from the group, wherein R ³³ represents hydrogen and a linear or branched alkyl group having 1 to 24 carbon atoms or a substituted or unsubstituted aryl group, and a hydrocarbon chain of R ^{26 to} R ³¹ Are bonded to each other at any position to form a divalent chain that forms a cyclic structure of at least one or more 3- to 7-membered saturated or unsaturated hydrocarbons with carbon atoms substituted by such groups. May be formed like this Carbonyl annularly connecting chain, ether, ester, amide, sulfide, sulfinyl, sulfonyl, may include imino at an arbitrary position, n _a is sandwiched benzene ring having a substituent group R ²⁷ to R ³⁰ and heterocycle Represents the number of condensed rings formed, and is an integer of 0 or 1 to 3.)

(In the formula ^(8), the R 34 ^{to R 42} are each _{^{independently, H, -SO 3 -, -SO}} 3 - M +, -SO 3 H, -R 43 SO 3 -, -R 43 SO 3 - M _{^{+, -R 43 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 43) 2, -NHCOR 43, -OH, ^{-O -, -SR 43, -OR 43} , -OCOR 43, -NO 2, -COO - M +, -COOH, -R 43 COOH, -R 43 COO - M +, -COOR 43, -COR 43, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the formula (1), and R ⁴³ is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, An arylene or aralkylene group And at least one of _-SO of _{^{R 34 ~R 42 3 -, -SO}} 3 H, -R 43 SO 3 -, -R 43 SO 3 H, -COOH, -R 43 COOH, and -SO ₃ ^- M _{^{+, -R 43 SO 3 - M}} +, -COO - M +, -R 43 COO - a group selected from the group consisting of ^{M +,} _{n b} is a benzene ring having a substituent ^{R 34} and ^{R 35} This represents the number of condensed rings sandwiched between benzene rings having substituents R ^{37 to} R ⁴⁰ , and is an integer of 0 or 1-3.

(In the formula (9), R ^{44 to} R ⁵³ are each independently H, —SO ₃ ^— , —SO ₃ ^— M ⁺ , —SO ₃ H, —R ⁵⁴ SO ₃ ^— , —R ⁵⁴ SO ₃ ^— M. _{^{+, -R 54 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 54) 2, -NHCOR 54, -OH, ^{-O -, -SR 54, -OR 54} , -OCOR 54, -NO 2, -COO - M +, -COOH, -R 54 COOH, -R 54 COO - M +, -COOR 54, -COR 54, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the formula (1), R ⁵⁴ is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, An arylene or aralkylene group And at least one of _-SO of _{^{R 44 ~R 53 3 -, -SO}} 3 H, -R 54 SO 3 -, -R 54 SO 3 H, -COOH, -R 54 COOH, and -SO ₃ ^- M _{^{+, -R 54 SO 3 - M}} +, -COO - M +, -R 54 COO - a group selected from the group consisting of ^{M +,} _{n c} is a benzene ring having a substituent ^R 44 ^{to R 46} This represents the number of condensed rings sandwiched between benzoquinone rings and is an integer of 0 or 1-3.)

(In the formula ^(10), each independently R 55 ^{to R 59 _{is, H, -SO 3 -, -SO}} 3 - M +, -SO 3 H, -R 60 SO 3 -, -R 60 SO 3 - M _{^{+, -R 60 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 60) 2, -NHCOR 60, -OH, ^{-O -, -SR 60, -OR 60} , -OCOR 60, -NO 2, -COO - M +, -COOH, -R 60 COOH, -R 60 COO - M +, -COOR 60, -COR 60, Selected from the group consisting of —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the above formula (1), R ⁶⁰ is an alkyl, aryl or aralkyl group or alkylene having 1 to 24 carbon atoms, An arylene or aralkylene group Ri, and at least one of _-SO ³ of _{^{R 55 ~R 59 -, -SO 3}} H, -R 60 SO 3 -, -R 60 SO 3 H, -COOH, -R 60 COOH, and -SO ₃ ^{- _{M +, -R 60 SO 3 -}} M +, -COO - M +, -R 60 COO - is a group selected from the group consisting of ^{M +, X a-} is chloride, bromide, iodide, Fluorine ion, nitrate ion, sulfate ion, hydrogen sulfate ion, phosphate ion, borofluoride ion, perchlorate ion, thiocyanate ion, acetate ion, propionate ion, methanesulfonate ion, p-toluenesulfonate ion, A is an at least one anion selected from the group of 1 to 3 anions composed of trifluoroacetate ions and trifluoromethanesulfonate ions, Of represents an ion valence, an integer of 1 to 3, p is doping ratio, its value is 0.001.)

Moreover, polyethylene dioxythiophene polystyrene sulfate is mentioned as another preferable electroconductive polymer (A). This conductive polymer has a structure in which polystyrene sulfonic acid is added as a dopant, although no sulfonic acid group is introduced into the skeleton of the conductive polymer. In addition, as the conductive polymer (A) having an acidic ammonium salt, polyethylene dioxythiophene polystyrene sulfonate ammonium or substituted ammonium salt may be used. This conductive polymer has a structure in which ammonium sulfonate group is not introduced into the skeleton of the conductive polymer, but polystyrene sulfonate ammonium salt is added as a dopant.
As specific examples of these conductive polymers (A), 3,4-ethylenedioxythiophene (Baytron M manufactured by Bayer) is polymerized with an oxidizing agent such as iron toluenesulfonate (Baytron C manufactured by Bayer). Examples include adducts of polyethylenedioxythiophene and polystyrene sulfonic acid to be produced, or those obtained by reacting this adduct with amines or ammonia. Moreover, what was obtained by reacting Baytron P (manufactured by Bayer) or Baytron P with amines and / or ammoniums can be used.

  Among these other preferable conductive polymers (A), those containing 20 to 100% of the repeating unit represented by the following general formula (11) in the total number of repeating units of the whole polymer are more preferable.

(In formula (11), y represents an arbitrary number of 0 <y <1, and R ^{61 to} R ⁷⁸ are each independently H, —SO ₃ ⁻ , —SO ₃ ⁻ M ⁺ , —SO ₃ H, _{^{-R 79 SO 3 -, -R 79}} SO 3 - M +, -R 79 SO 3 H, -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, - _{^{N (R 79) 2, -NHCOR}} 79, -OH, -O -, -SR 79, -OR 79, -OCOR 79, -NO 2, -COO - M +, -COOH, -R 79 COOH, -R ⁷⁹ COO ⁻ M ⁺ , —COOR ⁷⁹ , —COR ⁷⁹ , —CHO and —CN, wherein M ⁺ is an ammonium ion represented by the formula (1), and R ⁷⁹ is carbon. An alkyl, aryl or aralkyl group of 1 to 24 or alkylene Arylene or aralkylene ^group, at least one of _-SO of _{^{R 61 ~R 78 3 -, -SO}} 3 H, -R 79 SO 3 -, -R 79 SO 3 H, -COOH, -R 79 COOH, and _{^{-SO 3 - M +, -R 79}} SO 3 - M +, -COO - M +, -R 79 COO - is a group selected from the group consisting of ^{M +).}

  Among the conductive polymers (A), the content of the repeating unit having an acidic group with respect to the total number of repeating units of the polymer is from the point that the solubility in a solvent such as an organic solvent or a water-containing organic solvent is very good. A thing of 50% or more is preferable. The content of the repeating unit having an acidic group is more preferably 70% or more, further preferably 90% or more, and particularly preferably 100%.

  The substituent added to the aromatic ring is preferably an alkyl group, an alkoxy group, or a halogen group from the viewpoint of conductivity and solubility, and particularly preferably an alkoxy group having an electron donating property. Among these combinations, the most preferable conductive polymer (A) is represented by the following general formula (12).

(In the formula ^{(12), R} 80 ~R ⁸³ is a sulfonic acid group, a carboxy group, and alkali metal salts thereof, is one group selected from the group consisting of ammonium salts and substituted ammonium ^{salts, R 80} ~ At least one of R ⁸³ is a group selected from the group consisting of a sulfonic acid group, a carboxy group, and ammonium salts thereof, and R ⁸⁴ is a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, n-butyl, iso-butyl, sec-butyl, tert-butyl, dodecyl, tetracosyl, methoxy, ethoxy, n-propoxy, iso-butoxy, sec-butoxy, tert-butoxy Group, heptoxy group, hexoxy group, octoxy group, dodecoxy group, tetracosoxy group, fluoro group, chloro group and bromo group 1 represents a group selected from the group consisting of: x represents an arbitrary number of 0 <x <1, and m represents a degree of polymerization and is 3 or more.)
Among them, R ^{80 to} R ⁸³ are preferably sulfonic acid groups and alkali metal salts, ammonium salts and substituted ammonium salts of sulfonic acid groups in terms of high conductivity.

  The conductive polymer (A) in the present invention can be obtained by various synthetic methods such as chemical polymerization or electrolytic polymerization. For example, the synthesis methods described in JP-A-7-196791 and JP-A-7-324132 proposed by the present inventors can be applied. That is, one compound selected from the group consisting of an acidic group-substituted aniline represented by the following general formula (13), an alkali metal salt thereof, an ammonium salt, and a substituted ammonium salt is oxidized with an oxidizing agent in a solution containing a basic compound. A conductive polymer (A) can be obtained by polymerization.

(In the formula ^{(13), R} 85 ~R ⁹⁰ are each _{^{independently, H, -SO 3 -, -SO}} 3 - M +, -SO 3 H, -R 91 SO 3 -, -R 91 SO 3 - M _{^{+, -R 91 SO 3 H,}} -OCH 3, -CH 3, -C 2 H 5, -F, -Cl, -Br, -I, -N (R 91) 2, -NHCOR 91, -OH, ^{-O -, -SR 91, -OR 91} , -OCOR 91, -COO - M +, -COOH, -R 91 COOH, -R 91 COO - M +, -COOR 91, -COR 91, -CHO and - Selected from the group consisting of CN, wherein M ⁺ is an ammonium ion represented by the formula (1), and R ⁹¹ is an alkyl, aryl or aralkyl group or alkylene, arylene or aralkylene group having 1 to 24 carbon atoms. And R ⁸⁵ At least one of _-SO ³ of _{^{~R 90 -, -SO 3 H,}} -R 91 SO 3 -, -R 91 SO 3 H, -COOH, -R 91 COOH, and _-SO ³ - ^M +, -R ⁹¹ SO ₃ ⁻ M ⁺ , —COO ⁻ M ⁺ , and —R ⁹¹ COO ⁻ M ⁺ .

  A particularly preferable conductive polymer (A) is a conductive polymer obtained by polymerizing an alkoxy group-substituted aminobenzenesulfonic acid, its alkali metal salt, ammonium salt, or substituted ammonium salt with an oxidizing agent in a solution containing a basic compound. It is a polymer.

  As a simple method for synthesizing a conductive polymer having an ammonium salt of a sulfonic acid group and / or an ammonium salt of a carboxy group from the conductive polymer (A), ammonium salts represented by the following general formula (14) and A method of reacting an amine represented by the following general formula (15) and the conductive polymer (A) in a solution is mentioned.

(In the formula (14), R ^{101 to} R ¹⁰⁴ are each independently hydrogen, R ¹⁰⁵ OH, alkyl having 1 to 24 carbon atoms, aryl or aralkyl group, phenyl group, benzyl group, CONH ₂ or NH ₂ , and At least one of R ^{101 to} R ¹⁰⁴ is a group having 5 or more carbon atoms, R ¹⁰⁵ is an alkylene, arylene or aralkylene group having 1 to 24 carbon atoms, and Y ^b− is a hydroxide ion, a chlorine ion, or a bromine. Ion, iodine ion, fluorine ion, nitrate ion, sulfate ion, hydrogen sulfate ion, amidosulfuric acid ion, sulfite ion, phosphinate ion, phosphate ion, pyrophosphate ion, tripolyphosphate ion, borofluoride ion, perchlorate ion , Thiocyanate ion, acetate ion, propionate ion, methanesulfonate ion, p-tolu Sulfonate ion, valerate ion, dodecylbenzene sulfonate ion, camphor sulfonate ion, butyrate ion, formate ion, trimethyl acetate ion, bromoacetate ion, lactate ion, citrate ion, succinate ion, oxalate ion, tartaric acid ion , Fumarate ion, maleate ion, malonate ion, ascorbate ion, anisate ion, anthranilate ion, benzoate ion, cinnamic acid ion, phenylacetate ion, phthalate ion, aniline sulfonate ion, thiocarboxylate ion And at least one anion selected from the group of 1 to 3 anions consisting of methylsulfinate ion, trifluoroacetate ion, and trifluoromethanesulfonate ion, and b is the ionic valence of Y. Yes, an integer from 1 to 3 Shown, j is an integer of 1-3.)

(In the formula (15), R ^{106 to} R ¹⁰⁸ are each independently hydrogen, alkyl having 1 to 24 carbon atoms, aryl or aralkyl group, phenyl group, benzyl group, R ¹⁰⁹ OH, CONH ₂ or NH ₂ ; And at least one of R ^{106 to} R ¹⁰⁸ is a group having 5 or more carbon atoms, wherein R ¹⁰⁹ is an alkylene, arylene or aralkylene group having 1 to 24 carbon atoms.

  Examples of ammonium salts include alkyldimethylbenzylammonium halides such as benzalkonium chloride and trimethylbenzylammonium chloride, alkyldiethylbenzylammonium halides such as alkyldiethylbenzylammonium chloride and triethylbenzylammonium bromide, and trioctylmethylammonium chloride. Preferred are tetraalkylammonium halides and trimethylbenzylammonium hydroxide.

  Examples of amines include benzylamine, tri-n-octylamine, di-n-octylamine, 2-ethylhexylamine, 3- (2-ethylhexyloxy) propylamine, aniline, dimethylaniline, diethylaniline, di- Anilines such as n-propylaniline and di-iso-propylaniline are preferred.

  The mass average molecular weight of the conductive polymer (A) is preferably 2,000 to 3,000,000, and 3,000 to 1,000,000 in terms of polyethylene glycol in gel permeation chromatography (GPC). More preferably, it is particularly preferably 5,000 to 500,000. When the mass average molecular weight of the conductive polymer (A) is 2,000 or more, sufficient film strength, film formability, and conductivity are easily obtained. Moreover, if the mass average molecular weight of a conductive polymer (A) is 3,000,000 or less, the outstanding solubility will be easy to be obtained.

The conductive polymer (A) can be used as it is, but a conductive polymer (A) may be used which has been subjected to a known acid doping treatment method to which an external dopant is added. For example, the doping treatment can be performed by a treatment such as immersing a conductor containing the conductive polymer (A) in an acidic solution.
Specifically, the acidic solution used for the doping treatment includes inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid; organic acids such as p-toluenesulfonic acid, camphorsulfonic acid, benzoic acid, and derivatives having these skeletons; polystyrene sulfonic acid , Polyvinyl sulfonic acid, poly (2-acrylamido-2-methylpropane) sulfonic acid, polyvinyl sulfuric acid and aqueous solutions containing polymer acids such as derivatives having these skeletons, or water-organic solvent mixed solutions. These inorganic acids, organic acids, and polymer acids may be used alone, or two or more kinds may be mixed and used in an arbitrary ratio.

[Nanocarbon material (B)]
The nanocarbon material (B) of the present invention is not particularly limited as long as it is a carbon material having a nanosize size. Examples of the nanocarbon material (B) include fullerene, metal-encapsulated fullerene, onion-like fullerene, carbon nanotube, carbon nanohorn, carbon nanofiber, peapod, vapor grown carbon (VGCF), graphite, graphene, carbon nanoparticle, kettle Examples include chain black. Among these, carbon nanotubes are preferred from the viewpoints of conductivity, transparency, and orientation in fibers.

  Carbon nanotubes are not particularly limited, and ordinary carbon nanotubes can be used. For example, single-walled carbon nanotubes, multi-walled carbon nanotubes in which several layers are concentrically overlapped, or those in which these are coiled are used. be able to.

  In addition, as the carbon nanotube, a cylinder with a graphite-like carbon atom surface rounded in a layer of several atoms in thickness is a single layer or a plurality of nested structures, and an extremely minute substance having an outer diameter of nm order can be mentioned. It is done. In addition, a carbon nanohorn having a shape in which one side of the carbon nanotube is closed, a cup-shaped nanocarbon material having a hole in the head thereof, or the like can also be used.

  The method for producing carbon nanotubes in the present invention is not particularly limited. Specifically, catalytic hydrogen reduction of carbon dioxide, arc discharge method, laser evaporation method, CVD method, vapor phase growth method, gas phase flow method, carbon monoxide is reacted with iron catalyst at high temperature and high pressure in the gas phase. Examples include HiPco method for growth.

  The carbon nanotubes are preferably single-walled carbon nanotubes and multi-walled carbon nanotubes obtained by these production methods, and from the point that various functions are more easily expressed, further, washing methods, centrifugal separation methods, filtration methods, oxidation methods, The carbon nanotubes are more preferably purified by various purification methods such as chromatographic methods.

  In addition, as the nanocarbon material (B), the above-mentioned material is pulverized using a ball-type kneading apparatus such as a ball mill, a vibration mill, a sand mill, a roll mill, or the like, or cut short by chemical or physical treatment. What has been used can also be used.

  A nanocarbon material (B) may be used individually by 1 type, and may use 2 or more types together.

[Solvent (C)]
The solvent (C) in the present invention plays a role of further improving the solubility and dispersibility of the conductive polymer (A) and the nanocarbon material (B), and improving the spinnability, operability and the like. The solvent (C) is not particularly limited as long as it dissolves or disperses the nanocarbon material (B), but a solvent (C) that dissolves or disperses the conductive polymer (A) is preferable.

Examples of the solvent (C) include alcohols such as water, methanol, ethanol, isopropyl alcohol, propyl alcohol and butanol; ketones such as acetone, methyl ethyl ketone, ethyl isobutyl ketone, methyl isobutyl ketone and diacetone alcohol; ethyl acetate and n acetate -Esters such as butyl, isobutyl acetate, n-amyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate; ethylene glycols such as ethylene glycol, ethylene glycol methyl ether, ethylene glycol mono-n-propyl ether; propylene glycol, propylene Glycol methyl ether, propylene glycol ethyl ether, propylene glycol butyl ether, propylene glycol propyl ether Propylene glycols such as propylene glycol monomethyl ether acetate; amides such as dimethylformamide and dimethylacetamide; pyrrolidones such as N-methylpyrrolidone and N-ethylpyrrolidone; dimethylsulfoxide, γ-butyrolactone, methyl lactate, ethyl lactate, Hydroxyesters such as methyl β-methoxyisobutyrate and methyl α-hydroxyisobutyrate; anilines such as aniline and N-methylaniline, aromatic hydrocarbons such as benzene, toluene and xylene, m-cresol, acetonitrile, tetrahydro Furan, 1,4-dioxane, ethyl cellosolve, butyl cellosolve, and methoxypropanol are preferred.
Among these, water or a water-containing organic solvent is more preferable from the viewpoint of the solubility of the conductive polymer (A) and the dispersibility of the nanocarbon material (B), and examples of the organic solvent in the water-containing organic solvent include alcohols and ketones. Preferably used.

[Polymer Compound (D)]
In addition, the nanocarbon-containing composition in the present invention is obtained by adding a polymer compound (D) different from the conductive polymer (A) to improve spinnability and to obtain nanocarbon obtained by firing by heat treatment. The strength of the nanocarbon-containing fiber before forming the structure fiber can be improved.
The polymer compound (D) is not particularly limited as long as it can be dissolved or dispersed in the nanocarbon-containing composition in the present invention. For example, polyvinyl alcohols such as polyvinyl alcohol, polyvinyl formal, and polyvinyl butyral; polyacrylamide Polyacrylamides such as poly (Nt-butyl acrylamide) and polyacrylamide methylpropane sulfonic acid; polyvinyl pyrrolidone, polystyrene sulfonic acid and its soda salts, polyoxyethylene resin, cellulose, alkyd resin, melamine resin , Urea resin, phenol resin, epoxy resin, polybutadiene resin, acrylic resin, urethane resin, vinyl ester resin, urea resin, polyimide resin, maleic acid resin, polycarbonate resin, vinyl acetate resin, chlorine Polyethylene resins, chlorinated polypropylene resins, styrene resins, acryl / styrene copolymer resin, a vinyl acetate / acrylic copolymer resin, polyester resin, styrene / maleic acid copolymer resins, fluorine resins and copolymers thereof and the like can be used.
These high molecular compounds (D) may be used individually by 1 type, and may use 2 or more types together.

  Among these polymer compounds (D), when a conductive polymer having an ammonium salt of a sulfonic acid group and / or an ammonium salt of a carboxy group is used as the conductive polymer (A), solubility in a solvent, In terms of stability and conductivity, alkyd resin, melamine resin, urea resin, phenol resin, epoxy resin, polybutadiene resin, acrylic resin, acrylonitrile resin, urethane resin, vinyl ester resin, urea resin, polyimide resin, maleic acid resin, Polycarbonate resin, vinyl acetate resin, styrene resin, acrylic / styrene copolymer resin, vinyl acetate / acrylic copolymer resin, polyester resin, styrene / maleic acid copolymer resin are preferable, phenol resin, epoxy resin, polybutadiene resin, acrylic resin, Urethane resin, Acrylic / styrene copolymer resin, it is particularly preferred to use a mixture of one or more of the vinyl acetate / acrylic copolymer resin. The molecular weight of the polymer compound (D) is preferably 10,000 or more.

  In addition, when the conductive polymer (A) having an acidic group that does not form an ammonium salt is used, the solubility of the water-soluble polymer compound or the polymer compound that forms an emulsion in an aqueous system in a solvent and the stability of the composition From the viewpoints of conductivity and conductivity, a polymer compound having an anion group is preferable. Polyvinyl alcohol resin, polyoxyethylene resin, aqueous acrylic resin, aqueous polyester resin, aqueous urethane resin, aqueous chlorinated polyolefin resin, and tetrafluoroethylene resin It is more preferable to use a mixture of one or more water-based fluororesins.

  Furthermore, the polymer compound (D) is a high-temperature compound that burns off under the same heat treatment conditions as the conductive polymer (A) in the baking step of heating and burning the conductive polymer (A) after the coating film forming step. Molecular compounds are preferred.

[Basic compound (E)]
The nanocarbon-containing composition in the present invention further contains a basic compound (E) in addition to the conductive polymer (A), nanocarbon material (B), solvent (C), and polymer compound (D) described above. It is preferable. By adding the basic compound (E) to the nanocarbon-containing composition, the conductive polymer (A), which is a constituent component, is dedoped, and plays a role of further improving the solubility in the composition. Further, by forming a salt with a free acidic group, the dissolution of the conductive polymer (A) in the composition is particularly improved, and the solubilization or dispersion of the nanocarbon material (B) in the composition is promoted. Let Furthermore, the electrospinning property of the spinning solution containing an electrolyte such as the conductive polymer (A) is improved.

The basic compound (E) is not particularly limited, but ammonia, aliphatic amines, cyclic saturated amines, cyclic unsaturated amines, ammonium salts, and inorganic bases are preferable.
The structural formula of ammonia and aliphatic amines is shown in the following general formula (16). The structural formula of ammonium salts is shown in the following general formula (17).

(In the formula ^{(16), R} 201 ~R ²⁰³ is each independently of the other represents hydrogen, an alkyl group having 1 to 4 carbon _{atoms, CH 2 OH, CH 2 CH} 2 OH, a CONH ₂ or NH _2.)

(In the formula ^(17), the R 204 ^{to R 207} are each independently of one another, represent hydrogen, an alkyl group having 1 to 4 carbon _{atoms, CH 2 OH, CH 2 CH} 2 OH, a CONH ₂ or NH _2, Z ^- is OH ⁻ , 1/2 · SO ₄ ²⁻ , NO ₃ ⁻ , 1 / 2CO ₃ ²⁻ , HCO ₃ ⁻ , 1/2 · (COO) ₂ ²⁻ , or R ²⁰⁸ COO ⁻ , R ²⁰⁸ represents carbon (It is a C 1-3 alkyl group.)

As the cyclic saturated amines, piperidine, pyrrolidine, morpholine, piperazine, derivatives having these skeletons, and ammonium hydroxide compounds thereof are preferable.
As the cyclic unsaturated amines, pyridine, α-picoline, β-picoline, γ-picoline, quinoline, isoquinoline, pyrroline, derivatives having these skeletons, and ammonium hydroxide compounds thereof are preferable.
As the inorganic base, hydroxide salts such as sodium hydroxide, potassium hydroxide and lithium hydroxide are preferable.

As for the basic compound (E), only one type may be used alone, or two or more types may be used in combination. For example, the conductivity of the resulting fiber or nonwoven fabric can be further improved by using a mixture of amines and ammonium salts. Specifically, NH ₃ / (NH ₄ ) ₂ CO ₃ , NH ₃ / (NH ₄ ) HCO ₃ , NH ₃ / CH ₃ COONH ₄ , NH ₃ / (NH ₄ ) ₂ SO ₄ , N (CH ₃ ) ₃ / CH ₃ COONH ₄ , N (CH ₃ ) ₃ / (NH ₄ ) ₂ SO _4, or the like may be used. Further, the mixing ratio (mass ratio) of these can be any ratio, but is preferably amines / ammonium salts = 1/10 to 10/1.

[Surfactant (F)]
Further, the nanocarbon-containing composition in the present invention may further contain a surfactant (F). By containing the surfactant (F), the solubilization or dispersion of the nanocarbon material (B) is further promoted, and the spinnability and conductivity are improved.

Examples of the surfactant (F) include alkylsulfonic acid, alkylbenzenesulfonic acid, alkylcarboxylic acid, alkylnaphthalenesulfonic acid, α-olefinsulfonic acid, dialkylsulfosuccinic acid, α-sulfonated fatty acid, N-methyl-N- Oleyl taurine, petroleum sulfonic acid, alkyl sulfuric acid, sulfated oil, polyoxyethylene alkyl ether sulfuric acid, polyoxyethylene styrenated phenyl ether sulfuric acid, alkyl phosphoric acid, polyoxyethylene alkyl ether phosphoric acid, polyoxyethylene alkyl phenyl ether phosphoric acid , Anionic surfactants such as naphthalenesulfonic acid formaldehyde condensates and their salts; primary to tertiary fatty amines, quaternary ammoniums, tetraalkylammoniums, trialkylbenzylammonium alkyls Rupyridinium, 2-alkyl-1-alkyl-1-hydroxyethylimidazolinium, N, N-dialkylmorpholinium, polyethylene polyamine fatty acid amide, urea condensate of polyethylene polyamine fatty acid amide, urea condensate of polyethylene polyamine fatty acid amide Cationic surfactants such as quaternary ammonium and salts thereof; N, N-dimethyl-N-alkyl-N-carboxymethylammonium betaine, N, N, N-trialkyl-N-sulfoalkylene ammonium betaine, Betaines such as N, N-dialkyl-N, N-bispolyoxyethylene ammonium sulfate betaine, 2-alkyl-1-carboxymethyl-1-hydroxyethylimidazolinium betaine, N, N-dialkylaminoalkylene Amphoteric surfactants such as aminocarboxylic acids such as phosphates; polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene polystyryl phenyl ether, polyoxyethylene-polyoxypropylene glycol, polyoxyethylene-poly Oxypropylene alkyl ether, polyhydric alcohol fatty acid partial ester, polyoxyethylene polyhydric alcohol fatty acid partial ester, polyoxyethylene fatty acid ester, polyglycerin fatty acid ester, polyoxyethylenated castor oil, fatty acid diethanolamide, polyoxyethylene alkylamine, Non-ionic surfactants such as triethanolamine fatty acid partial esters and trialkylamine oxides; and fluoroalkylcarboxylic acids, perfluoro Rukirukarubon acid, perfluoro benzene sulfonic acid, fluorine-based surfactants such as perfluoroalkyl polyoxyethylene ethanol. Here, the alkyl group preferably has 1 to 24 carbon atoms, and more preferably 3 to 18 carbon atoms.
These surfactants (F) may be used alone or in combination of two or more.

The nanocarbon-containing composition of the present invention may further include a plasticizer, a dispersant, a coating surface modifier, a fluidity modifier, an ultraviolet absorber, a storage stabilizer, an adhesion aid, and a thickener as necessary. , Various known polymers such as thermoplastic polymers other than the conductive polymer (A), slip agents, leveling agents, ultraviolet absorbers, polymerization inhibitors, antistatic agents, inorganic fillers, organic fillers, and surface-organized inorganic fillers. A substance may be included.
Moreover, in order to further improve the electroconductivity of a nanocarbon containing fiber and a nanocarbon structure fiber, a conductive substance can also be contained in a nanocarbon containing composition. Examples of the conductive material include carbon-based materials such as carbon fiber, conductive carbon black, and graphite, and metal fine particles and metal oxide fine particles.

The nanocarbon-containing composition in the present invention is a composition containing a conductive polymer (A), a nanocarbon material (B), a solvent (C) and a polymer compound (D) as described above. Accordingly, the basic compound (E) and the surfactant (F) can be further contained.
Hereinafter, these composition ratios will be described.

  The use ratio of the conductive polymer (A) and the solvent (C) is such that the conductive polymer (A) is 0.001 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the solvent (C). It is preferably 0.01 parts by mass or more and 30 parts by mass or less. If a conductive polymer (A) is 0.001 mass part or more, sufficient electroconductivity will be easy to be obtained and the efficiency of solubilization or dispersion | distribution of a nanocarbon material (B) will improve more. Moreover, if a conductive polymer (A) is 50 mass parts or less, it will be easy to suppress the fall of the efficiency of solubilization or dispersion | distribution of the nanocarbon material (B) by high viscosity. Moreover, even if a conductive polymer (A) exceeds 50 mass parts, electroconductivity does not increase greatly further.

  The use ratio of the nanocarbon material (B) and the solvent (C) is preferably such that the nanocarbon material (B) is 0.0001 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the solvent (C). Preferably they are 0.001 mass part or more and 10 mass parts or less. By setting the nanocarbon material (B) to 0.0001 part by mass or more, the conductivity can be improved, and the strength at the time of forming the structure is also improved. On the other hand, by setting it as 20 mass parts or less, the efficiency of solubilization or dispersion | distribution of nanocarbon material (B) can be made more favorable, and spinnability is also improved.

  The use ratio of the polymer compound (D) and the solvent (C) is preferably such that the polymer compound (D) is 0.1 parts by mass or more and 400 parts by mass or less with respect to 100 parts by mass of the solvent (C). More preferably, it is 0.5 to 300 parts by mass. When the polymer compound (D) is 0.1 part by mass or more, the moldability and strength of the nanocarbon-containing fiber obtained from the nanomaterial-containing composition are further improved, and as a result, the characteristics of the nanocarbon structure fiber itself Will also improve. Further, when the polymer compound (D) is 400 parts by mass or less, the solubility of the conductive polymer (A) and the nanocarbon material (B) is hardly decreased, and excellent spinnability and conductivity can be easily maintained.

  The use ratio of the basic compound (E) and the solvent (C) is preferably such that the basic compound (E) is 0.00001 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the solvent (C). More preferably, it is 0.00005 parts by mass or more and 5 parts by mass or less. When the basic compound (E) is 0.00001 part by mass or more, the solubility of the water-soluble conductive polymer (A) is increased, and the nanocarbon material (B) is solubilized or dispersed in the solvent (C). Is promoted, and the conductivity of the nanocarbon-containing fiber or nanocarbon structure fiber is further improved. Moreover, when a basic compound (E) exceeds 10 mass parts, there exists a possibility that the electroconductivity of a conductive polymer may fall.

  The use ratio of the surfactant (F) and the solvent (C) is preferably such that the surfactant (F) is 0.0001 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the solvent (C). More preferably, the content is 0.01 part by mass or more and 5 parts by mass or less. If surfactant (F) is 0.0001 mass part or more, spinnability, electroconductivity, and solubilization or dispersion | distribution of nanocarbon material (B) will improve more. Moreover, when surfactant (F) exceeds 10 mass parts, while the phenomenon of inferior electroconductivity etc. will arise, there exists a possibility that the solubilization or dispersion | distribution efficiency of nanocarbon material (B) may fall.

[Method for producing nanocarbon-containing composition]
In the present invention, by using the solvent (C), a nanocarbon-containing composition excellent in dispersibility and spinnability can be obtained, so that a high-performance fiber can be produced.
The conductive polymer (A), the nanocarbon material (B), the solvent (C), the polymer compound (D), and the basic compound (E as necessary) which are essential components of the nanocarbon-containing composition in the present invention. ), When mixing the surfactant (F) or the like, a stirring or kneading apparatus such as an ultrasonic wave, a homogenizer, a spiral mixer, a planetary mixer, a disperser, or a hybrid mixer is used. Among them, it is preferable to mix the conductive polymer (A), the nanocarbon material (B), the solvent (C), or other components, and irradiate this with ultrasonic waves. In this case, the ultrasonic irradiation and the homogenizer It is particularly preferable to carry out the treatment in combination (ultrasonic homogenizer).

The conditions of the ultrasonic irradiation treatment are not particularly limited, and may be any ultrasonic intensity and treatment time sufficient to uniformly disperse or dissolve the nanocarbon material (B) in the solvent (C). . For example, the rated output of the ultrasonic oscillator is preferably 0.1 to 500 watts / cm ² per unit bottom area of the ultrasonic oscillator. The oscillation frequency is preferably 10 to 200 kHz, and more preferably 20 to 100 kHz. In addition, the time for the ultrasonic irradiation treatment is preferably 1 minute to 48 hours, and more preferably 5 minutes to 48 hours. In addition, the temperature of the nanocarbon-containing composition when performing the ultrasonic irradiation treatment is preferably 60 ° C. or less, and more preferably 40 ° C. or less, from the viewpoint of improving dispersibility.
Further, after the ultrasonic irradiation treatment, it is preferable to thoroughly disperse or dissolve using a ball type kneader such as a ball mill, a bead mill, a vibration mill, a sand mill, or a roll mill.

  When mixing predetermined constituents, all the components may be added at once, or after preparing a concentrated nanocarbon-containing composition using a small amount of the solvent (C), the remaining components It may be diluted to a predetermined concentration with other components (polymer compound (D), basic compound (E), surfactant (F), other additives) such as solvent (C). When two or more types of solvents (C) are used in combination, a concentrated nanocarbon-containing composition is prepared using one or more components of the solvent (C) to be used, and then other solvents (C It may be diluted with component C).

<Nanocarbon-containing fiber and method for producing sheet-like or twisted-like structure comprising the same>
The nanocarbon-containing fiber of the present invention is produced by electrospinning a nanocarbon-containing composition that is a dope (spinning stock solution). For example, a high voltage of several kV to 200 kV is applied between the nozzle tip of a spinning syringe containing a nanocarbon-containing composition and a counter electrode substrate that is a collector portion, and the nanocarbon-containing composition is discharged from the nozzle by electrostatic repulsion. By drawing out, nanocarbon-containing fibers, which are nanofibers (fine fibers), are produced on the collector substrate and can be laminated as a nonwoven fabric (sheet-like structure).
Moreover, it is possible to manufacture a twisted-like structure by twisting a nanocarbon-containing fiber or a sheet-like structure made of nanocarbon-containing fibers.

The applied voltage in electrospinning is preferably 1 kV to 160 kV, more preferably 5 kV to 50 kV. If it is lower than 1 kV, the nanocarbon-containing composition does not become nanofiber, and if it is higher than 160 kV, discharge occurs between the nozzle and the collector and the nanocarbon-containing composition does not become nanofiber.

  The spinning humidity is preferably in the range of 0 to 70 relative%. When the spinning humidity is higher than 70 relative%, there is a possibility that induction of electric charge necessary for electrospinning does not occur at the nozzle tip, which is not preferable.

  The spinning temperature is preferably in the range of 5 to 50 ° C. A spinning temperature higher than 50 ° C. is not preferable because the solvent of the spinning solution may evaporate. If the spinning temperature is lower than 5 ° C., the solvent of the spinning solution may be solidified, which is not preferable.

  The distance between the nozzle and the collector is preferably 1 cm to 50 cm, more preferably 5 cm to 15 cm. When the interval is shorter than 1 cm, discharge occurs and the nanocarbon-containing composition does not become nanofiber. If the interval is longer than 50 cm, the nanocarbon-containing composition formed into nanofibers is not preferable because it does not adhere to the collector.

The supply flow rate of the nanocarbon-containing composition to the nozzle is preferably 1 to 500 μL / min, more preferably 1 to 300 μL / min. If the flow rate is slower than 1 μL / min, supply of the solution may be insufficient at the nozzle tip, and if the flow rate is faster than 500 μL / min, dripping may occur at the nozzle tip.

  The diameter of the nozzle is preferably 10 μm to 2 mm, more preferably 0.1 to 1 mm. When the nozzle diameter is smaller than 10 μm, the high viscosity spinning solution is clogged, which is not preferable. When the nozzle diameter is larger than 2 mm, it is not preferable because a low-viscosity spinning solution cannot be retained.

  The collector used in the present invention is preferably a plate-like material having the same electrical conductivity as a conductor or semiconductor. For example, copper plate, iron plate, stainless steel plate, gold plate, silver plate, brass plate, aluminum plate, laminated plate of these conductive plates and aluminum foil, glass substrate or polymer film coated with indium tin oxide, silicon substrate, etc. There is. Moreover, in order to obtain a fiber continuously, you may make it make the said board | plate which has the said electroconductivity into a belt, and rotate with a roll.

  In general, when a solution containing a polymer electrolyte is electrospun, fibers may not be deposited on the substrate, and a phenomenon may occur in which the solution grows vertically between the nozzle and the collector. Since the same phenomenon may occur in the case of the conductive polymer used in the present invention, a conductor or a semiconductor having an opening such as a ring shape is installed on the collector part installed at the lower part of the nozzle, and electrospinning is performed. It is preferable. When such a collector is used, a sheet-like structure made of nanocarbon-containing fibers can be produced in one step.

  The obtained nanocarbon-containing fiber is an ultrafine fiber having an average fiber diameter of 5 nm to 50 μm, the surface is coated with the conductive polymer (A) and the polymer compound (D), and the inside is a nanocarbon material (B). And has a structure oriented in the spinning direction (longitudinal direction). Moreover, since the nanocarbon material (B) has a high density and an agglomeration / orientation structure, properties such as conductivity are greatly improved.

[Nanocarbon structure fiber and method for producing sheet-like or twisted-like structure comprising the same]
[Baking process]
The nanocarbon structure fiber of the present invention can be obtained by burning the conductive polymer (A) or the polymer compound (D) by heating the nanocarbon-containing fiber of the present invention.
Moreover, the sheet-like or twisted yarn made of nanocarbon structure fibers is obtained by burning out the conductive polymer (A) or the polymer compound (D) by heating the sheet-like or twisted-like structure made of nanocarbon-containing fibers. A shaped structure can be obtained.
Moreover, although heat processing can be implemented also in air and inert gas atmosphere formation, in order to make a nanocarbon material (B) hard to burn down, it is preferable to implement by inert gas atmosphere. The inert gas is not particularly limited, but nitrogen gas or argon gas is often used.

  In the present specification, “firing” means that the conductive polymer (A) or the polymer compound (D) in the nanocarbon-containing fiber is burned out by heating. Accordingly, the heat treatment conditions (temperature, time, method, etc.) are not particularly limited as long as the conductive polymer (A) and the polymer compound (D) are burned off. However, it is not preferable that the nanocarbon material (B) in the nanocarbon-containing fiber is burned out because the conductive performance of the nanocarbon structure fiber after firing is lowered.

For example, any of the following heat treatment conditions (1) to (4) can be adopted as the heat treatment conditions for the nanocarbon-containing fiber.
Heat treatment condition 1: Heat in a temperature range of 350 ° C. or higher and lower than 400 ° C. for 30 minutes or longer.
Heat treatment condition 2: Heat in a temperature range of 400 ° C. or higher and lower than 450 ° C. for 15 minutes or longer.
Heat treatment condition 3: Heat in a temperature range of 450 ° C. or higher and lower than 500 ° C. for 3 minutes or longer.
Heat treatment condition 4: Heat in a temperature range of 500 ° C. or higher and lower than 600 ° C. for 1 minute or longer.

  When the heating temperature is less than 350 ° C., the water-soluble conductive polymer (A) is hardly burned down, and sufficient transparency cannot be imparted to the structure. On the other hand, when the heating temperature exceeds 600 ° C., the nanocarbon material (B) itself is burned out, and the structure itself that maintains the strength tends to be not formed because the fiber itself disappears.

  Moreover, although heating time changes with heating temperatures, it is 30 minutes or more in the temperature range of 350 degreeC or more and less than 400 degreeC, and it is preferable that it is 35 minutes or more and 180 minutes or less. In a temperature range of 400 ° C. or higher and lower than 450 ° C., it is 15 minutes or longer, and preferably 20 minutes or longer and 180 minutes or shorter. It is 3 minutes or more in a temperature range of 450 ° C. or more and less than 500 ° C., and preferably 5 minutes or more and 180 minutes or less. It is 1 minute or more in a temperature range of 500 ° C. or more and less than 550 ° C., and preferably 3 minutes or more and 180 minutes or less. When the heating time is less than the predetermined time under each condition, the conductive polymer (A) is not sufficiently burned out, and sufficient electrical conductivity cannot be imparted to the structure.

The heat treatment method is not particularly limited, but a method of heat-treating the nanocarbon-containing fiber by hot air drying, a hot plate, a heating furnace, an oven, vacuum drying, infrared drying, or the like is preferable.
In addition, the preferable heating time and heating temperature in the said baking process differ also with heating apparatuses. For example, when the heated part is in direct contact like a hot plate, the heating time tends to be short, and when not directly touching like an oven (heating furnace), the heating time tends to be long.

  The obtained nanocarbon structure fiber is an ultrafine fiber having an average fiber diameter of 10 nm to 10 μm, preferably 10 nm to less than 1 μm, and the conductive polymer (A) and the polymer compound (D) covering the surface. Is burned down by the heat treatment, and substantially maintains the structure composed of the nanocarbon material (B) that exists in a high-density orientation inside. Since the conductive polymer (A) and the insulating polymer compound (D) having lower conductivity than the nanocarbon material on the surface were burned down by the heat treatment, the conductivity of the nanocarbon material (B) itself can be expressed. “Substantially composed of the nanocarbon material (B)” means that the conductive polymer (A) and / or the high-carbon fiber as long as the nanocarbon structure fiber exhibits the desired properties of the nanocarbon material (B) itself. It means that a baking residue of the molecular compound (D) may be contained.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited by the following description.
(Production Example 1) Conductive polymer (A)
Synthesis of poly (2-sulfo-5-methoxy-1,4-iminophenylene):
100 mmol of 2-aminoanisole-4-sulfonic acid was dissolved in 40 mL of a 4 mol / L triethylamine aqueous solution at 25 ° C. with stirring, and a solution of 100 mmol of ammonium peroxodisulfate in 100 mL of water was added dropwise thereto. After completion of the dropwise addition, the mixture was further stirred at 25 ° C. for 12 hours, and then the reaction product was washed by filtration and dried to obtain 15 g of a polymer powder (conductive polymer (A)). The volume resistance value of this conductive polymer (A) was 9.0 Ω · cm.

The nanocarbon material (B) used was as follows.
Carbon nanotube (B): Multi-walled carbon nanotube “trade name: NC7000” manufactured by Nanosil Corporation by CVD (chemical vapor deposition method).
Hereinafter, the carbon nanotube may be abbreviated as “CNT”.

The solvent (C) used was as follows.
Ultrapure water produced using an ultrapure water production system (Milli-Q) commercially available from Nihon Millipore.

As the polymer compound (D), the following was used.
Polyethylene oxide having a molecular weight of 4 million (Cat. # 04030-500) commercially available from Polysignence. Hereinafter, it may be abbreviated as “PEO”.

<Nanocarbon-containing composition>
(Production Example 2: corresponding to Example 1)
The conductive polymer (A) and nanocarbon material (B) of Production Example 1 were mixed with the solvent (C) at a mass ratio of (A) / (B) / (C) = 1/1/99 at room temperature. And homogenizer treatment (Vibra cell 20 kHz, manufactured by SONIC) was carried out for 1 hour to prepare a uniformly dispersed solution of the conductive polymer (A) and the nanocarbon material (B).
A solvent (C) and a polymer compound (D) were mixed at room temperature so as to have the composition shown in Table 1 in this uniform dispersion solution, and after stirring for 20 hours or more, a nanocarbon-containing composition 1 was prepared.

(Production Example 3: corresponding to Example 2)
The conductive polymer (A) and nanocarbon material (B) of Production Example 1 were mixed with the solvent (C) at a mass ratio of (A) / (B) / (C) = 1/1/99 at room temperature. And homogenizer treatment (Vibra cell 20 kHz, manufactured by SONIC) was carried out for 1 hour to prepare a uniformly dispersed solution of the conductive polymer (A) and the nanocarbon material (B).
A solvent (C), a polymer compound (D) and a basic compound (E) are mixed at room temperature so as to have the composition shown in Table 1 in this uniformly dispersed solution, and after stirring for 20 hours or more, a nanocarbon-containing composition 2 was prepared.
(Production Example 4: corresponding to Comparative Example 1)
The composition 1 shown in Table 1 was prepared by mixing the conductive polymer (A) and polymer compound (D) of Production Example 1 with the solvent (C) at room temperature and stirring for 20 hours or more. A composition containing no nanocarbon material (B)).

<Nanocarbon-containing fiber>
(Examples 1 and 2 and Comparative Example 1)
The composition shown in Table 1 was put into a syringe and spun under the electrospinning conditions shown in Table 2. An aluminum ring-shaped structure was placed on an aluminum plate collector as a collector, and electrospinning was performed to produce a sheet-shaped structure at the ring portion. Moreover, the twisted-like structure was produced by twisting the nanocarbon containing fiber arranged on the aluminum collector rotating at a rotational speed of 2000 rpm.

<Evaluation method>
In the examples and comparative examples, the structure observation of the nanocarbon-containing fibers produced by the electrospinning method and the electrical conductivity measurement of the nanocarbon-containing fiber aggregates were performed.

(Resistance value)
The resistance values of the twisted and sheet-like structures were measured using a multi-channel AC four-terminal conductivity meter (HECS 994C type manufactured by Fuso Seisakusho). The electrical conductivity (σ) was calculated from the obtained resistance value (R), the measured length (L) of the sample, and the cross-sectional area (A) of the sample using the relational expression of σ = 1 / ρ = L / RA.
(Structure observation)
The fiber morphology was observed using a scanning electron microscope (SEM, SM-200 manufactured by TOPCON). Observation was performed under the condition of an acceleration voltage of 10 kV. In addition, as an observation sample, the surface of the fiber coated with gold having a thickness of about 5 nm using a fine coater (JFC-1200 manufactured by JEOL Ltd.) was used. From the obtained secondary electron image, the fiber diameters at 50 arbitrary points on the fiber were measured, and the average fiber diameter was determined. Moreover, the fiber internal structure was observed using the transmission electron microscope (TEM, JEOL JEM-2000CX).

(Observation and measurement results)
A scanning electron microscope (SEM) photograph of the sheet-like nanocarbon-containing fiber structure produced under the spinning conditions of Example 1 is shown in FIG. The average fiber diameter is 100 nm. FIG. 2 and FIG. 3 show SEM photographs of the aligned fiber produced on the rotating collector under the same spinning conditions as in Example 1 and the twisted nanocarbon-containing fiber structure obtained by twisting the aligned fiber, respectively. A transmission electron microscope (TEM) photograph of the nanocarbon-containing fibers produced in Example 1 is shown in FIG. In the nanocarbon-containing fiber, CNTs are dispersed with high density and uniformity. The electrical conductivity was 5 × 10 ⁻² S / cm for the sheet-like nanocarbon-containing fiber, and 2.6 S / cm for the twisted nanocarbon-containing fiber.
Further, the electrical conductivity of the twisted fiber prepared under the spinning conditions of Comparative Example 1 is 0.005 S / cm, and Example 1 containing CNT expresses 520 times higher electrical conductivity than Comparative Example 1. did.
Note that the array fiber shown in FIG. 2 is a fiber arrayed by winding a thread around the side surface of a disk-type collector that rotates at a speed higher than the spinning speed.

  In Example 2, a sheet-like structure composed of fibers having an average fiber diameter of 280 nm having the same structure as that in FIG. 1 was obtained.

  In Comparative Example 1, a sheet-like structure composed of fibers having an average fiber diameter of 200 nm shown in FIG. 5 was obtained.

<Nanocarbon structure fiber>
A nanocarbon structure obtained by heat-treating the nanocarbon-containing fiber assembly produced by the electrospinning method and the fiber of Comparative Example 1 in a nitrogen-substituted electric furnace (FUA112DB manufactured by Advantech Toyo Co., Ltd.) under the heating conditions shown in Table 3 Fiber was created.

<Evaluation method>
In Examples and Comparative Examples, appearance observation, structure observation, and electrical conductivity measurement of the nanocarbon structure fiber after the heat treatment were performed.

(Formation and appearance of structure)
The ability to maintain the shape was visually evaluated.
○: The structure was formed and maintained even after the heat treatment.
X: The structure was not formed and maintained due to the heat treatment.

(Resistance value)
The resistance values of the twisted and sheet-like structures were measured using a multi-channel AC four-terminal conductivity meter (HECS 994C type manufactured by Fuso Seisakusho) in the same manner as in Example 1. The electrical conductivity (σ) was calculated from the obtained resistance value (R), the measured length (L) of the sample, and the cross-sectional area (A) of the sample using the relational expression of σ = 1 / ρ = L / RA.
(Structure observation)
The fiber form was observed using a scanning electron microscope (SEM, SM-200 manufactured by TOPCON) in the same manner as in Example 1. Observation was performed under the condition of an acceleration voltage of 10 kV. In addition, as an observation sample, the surface of the fiber coated with gold having a thickness of about 5 nm using a fine coater (JFC-1200 manufactured by JEOL Ltd.) was used. From the obtained secondary electron image, the fiber diameters at 50 arbitrary points on the fiber were measured, and the average fiber diameter was determined.

  As shown in Table 3, the nanocarbon-containing fibers of Examples 1 and 2 of the present invention are nanofibers having an average fiber diameter of nano-order. The structure which maintained the sheet-like or twisted-like shape of Examples 3 and 4 was able to be produced by heat-treating the sheet-like or twisted-like nanocarbon-containing fiber structure.

  The SEM photograph of the sheet-like nanocarbon structure fiber processed on the heating conditions of Example 3 is shown in FIG. The average fiber diameter is 100 nm. Moreover, the SEM photograph of the twisted nanocarbon structure fiber processed on the heating conditions of Example 4 is shown in FIG. The electrical conductivity was 4.5 S / cm for the sheet-like nanocarbon-containing fiber, and 11.6 S / cm for the twisted nanocarbon-containing fiber.

  On the other hand, in Comparative Example 2, the heat treatment conditions are the same, but since the nanocarbon material does not exist inside, the conductive polymer (A) and the polymer compound (D) forming the fibers are burned out, The structure could not be formed and maintained.

  The nanocarbon-containing fiber and nanocarbon structure fiber of the present invention include a capacitor and a functional capacitor, a battery, a secondary battery, a capacitor, a fuel cell, a solar cell (such as an organic solar cell and a dye-sensitized solar cell), and a polymer thereof. Electrolyte membranes, electrode layers, catalyst layers, gas diffusion layers, gas diffusion electrode layers, separators, buffer materials between each layer, members such as low ESR (equivalent series resistance) materials, EMI shields (electromagnetic interference shields), chemical sensors, Display elements, nonlinear materials, anticorrosives, adhesives, fibers, spinning materials, conductive materials, conductive paints, antistatic paints, anticorrosive paints, electrodeposition paints, plating primers, conductive primers for electrostatic coating, and anticorrosion , Improvement of battery storage capacity, industrial packaging materials such as semiconductors, electrical and electronic parts, overhead projector films, electrophotographic recording materials such as slide films, etc. Antistatic film, audio tape, video tape, computer tape, magnetic recording tape such as floppy disk, antistatic, LSI wiring of electronic devices, electron gun (source) and electrode of field emission display (FED), hydrogen Storage agent, further transparent touch panel, electroluminescence display, liquid crystal display, etc. Input and display device surface antistatic and transparent electrode, light emitting material forming organic electroluminescence element, buffer material, electron transport material, hole transport material and fluorescence It is useful because it can be used as a material, a thermal transfer sheet, a transfer sheet, a thermal transfer image receiving sheet, an image receiving sheet, a metal substitute material, and an electric wire.

Claims (6)

Nanocarbon-containing composition containing conductive polymer (A), nanocarbon material (B), solvent (C ), polymer compound (D) different from conductive polymer (A) , and basic compound (E) A method for producing a nanocarbon-containing fiber by electrospinning a product. The method of manufacturing the nano carbon structure fiber which burns down the said conductive polymer (A) and high molecular compound (D) by heating the nano carbon containing fiber manufactured by the method of Claim 1 . A sheet-like or twisted-like structure comprising nanocarbon-containing fibers produced by the method according to claim 1 . A sheet-like or twisted-like structure made of nanocarbon structure fibers produced by the method according to claim 2 .   A nanocarbon-containing fiber comprising a conductive polymer (A), a nanocarbon material (B), and a polymer compound (D) different from the conductive polymer (A), the surface of which is the conductive material It is coated with the polymer (A) and the polymer compound (D), the nanocarbon material (B) is oriented in the longitudinal direction of the fiber, and the average fiber diameter is in the range of 5 nm to 50 μm. Nanocarbon-containing fiber.   Nanocarbon structure fiber which consists of nanocarbon material (B) substantially, and has an average fiber diameter in the range of 10 nm-less than 1 micrometer.