JP4565384B2 - Method for producing carbon nanofibers with excellent dispersibility in resin - Google Patents

Method for producing carbon nanofibers with excellent dispersibility in resin Download PDF

Info

Publication number
JP4565384B2
JP4565384B2 JP2004345423A JP2004345423A JP4565384B2 JP 4565384 B2 JP4565384 B2 JP 4565384B2 JP 2004345423 A JP2004345423 A JP 2004345423A JP 2004345423 A JP2004345423 A JP 2004345423A JP 4565384 B2 JP4565384 B2 JP 4565384B2
Authority
JP
Japan
Prior art keywords
carbon
carbon nanofibers
resin
method
gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2004345423A
Other languages
Japanese (ja)
Other versions
JP2006152490A (en
Inventor
浩之 今井
修 坂谷
Original Assignee
三菱マテリアル株式会社
三菱マテリアル電子化成株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 三菱マテリアル株式会社, 三菱マテリアル電子化成株式会社 filed Critical 三菱マテリアル株式会社
Priority to JP2004345423A priority Critical patent/JP4565384B2/en
Publication of JP2006152490A publication Critical patent/JP2006152490A/en
Application granted granted Critical
Publication of JP4565384B2 publication Critical patent/JP4565384B2/en
Application status is Active legal-status Critical
Anticipated expiration legal-status Critical

Links

Images

Description

The present invention relates to a method for producing carbon nanofibers excellent in dispersibility for a resin. More specifically, the surface has a lipophilic amorphous carbon layer, and therefore has a high dibutyl phthalate oil absorption amount (DBP oil supply amount: hereinafter sometimes referred to simply as oil absorption amount), and has excellent dispersibility for resins. The present invention relates to a fiber manufacturing method . The carbon nanofibers of the present invention are suitable as fillers for plastics, ceramics, paints, etc., and can be widely used for various molding materials, parts, conductivity imparting materials and reinforcing materials in various fields such as batteries and capacitors.

Conventionally, this type of carbon nanofiber has been synthesized by an electrode discharge method, a vapor phase growth method, a laser method, or the like. Among these, the vapor phase growth method using a catalyst is a method in which a raw material gas is supplied into a heated apparatus and thermally decomposed, and carbon is grown in the length direction using metal catalyst particles such as iron and nickel as nuclei. . Since this method is excellent in mass productivity, various improvement methods have been attempted, and various studies have been made on catalyst particles. Generally, metal fine particles such as iron, nickel and cobalt or oxides carrying metal fine particles (alumina, silica, zeolite, etc.) are known (Patent Document 1).

However, the carbon nanofibers produced by the conventional method have inferior chemical stability, a high production temperature, and a problem of high cost because graphitization is performed to improve crystallinity. In order to solve this problem, chemical stability is achieved by using specific metal fine particles as a catalyst and using carbon monoxide gas or a mixed gas of carbon dioxide gas and hydrogen gas instead of conventional hydrocarbon as the raw material gas. A method for producing carbon nanofibers having a high temperature at a lower temperature than conventional ones has been developed (Patent Document 2).
JP 2003-206117 A JP 2004-299986 A

Conventional carbon nanofibers have been studied for shape, structure, etc., but dispersibility in the resin is not considered. However, the dispersibility of the carbon nanofiber has a great influence on the physical properties of the composition containing the carbon nanofiber. For example, the conventional carbon nanofiber is about 10 to 50 ml / 100 g with respect to the DBP oil supply amount serving as an index of dispersibility for the resin. In a resin composition containing carbon nanofibers having such a low DBP oil absorption amount and thus low dispersibility, the physical properties of the resin are gradually impaired as the carbon nanofiber content increases, and the extensibility of the resin composition is reduced. This greatly reduces the spinning ability, makes the conductivity non-uniform, causes a large change in specific resistance with respect to temperature and humidity, and causes problems such as a decrease in kneadability and moldability.

This invention solves the said conventional subject, Comprising: The manufacturing method of the carbon nanofiber excellent in the dispersibility which uses DBP oil absorption amount as a parameter | index with respect to resin is provided. In the present invention, the carbon nanofiber is, for example, a nano-sized ultrafine carbon fiber having a diameter of several tens of nanometers or less and a length of several hundreds of micrometers or less, and is not limited to a carbon nanotube having a hollow structure. Including the structure filled inside, including the case where the carbon layer is either a single layer structure or a multilayer structure, the carbon layer is not limited to a spiral structure, and the carbon layer extends in the axial direction of the fiber. Not only the thing of the structure where the carbon layer extended in the diameter direction is included.

The present invention relates to the following method for producing carbon nanofibers.
[1] As catalyst particles, one or more selected from oxides of Fe, Ni, Co, Mn, and Cu, and one or more selected from oxides of Mg, Ca, Al, and Si In the vapor phase growth method for producing carbon nanofibers, the mixed oxide powder is used, and the catalyst particles are brought into contact with carbon monoxide and / or a mixed gas of carbon dioxide and hydrogen at a temperature of 400 ° C. to 800 ° C. A method for producing a carbon nanofiber having an amorphous carbon layer having a lipophilic surface by adjusting a catalyst and a mixed gas composition.
[2] In the production method of the above [1], a mixed powder of Co 3 O 4 and MgO or a powder whose surface of MgO is coated with Co 3 O 4 is used as a catalyst, and the CO / H 2 ratio of the raw material mixed gas Is adjusted to 50/50 to 99/1, and after the reaction, carbon nanofibers having a DBP oil absorption of 150 ml / 100 g or more are produced by continuously treating with hydrogen gas at the same temperature as the reaction temperature for 10 minutes or more. Method.

Since the carbon nanofiber of the present invention has a DBP oil absorption of 150 ml / 100 g or more, it has excellent dispersibility in the resin and maintains the original tensile strength and extensibility of the resin even when blended in a larger amount than before. can do. In addition, since the carbon nanofibers of the present invention have good dispersibility, a high electrical conductivity and strength reinforcing effect can be obtained even if a relatively small amount is added to the resin.

The carbon nanofiber according to the present invention has, for example, a DBP oil absorption of 150 ml / 100 g or more, a volume resistance value of the compacted body of 1.0 Ωcm or less, a diameter of 5 to 100 nm, an aspect ratio of 10 or more, and a BET specific surface area of 400 m 2 / The inside which is g or less is a carbon nanofiber (carbon nanotube) having a hollow structure. This is suitable as a conductive filler, and what is blended in a resin is widely used as a conductive material such as a conductive sheet, conductive yarn, conductive coating material, conductive coating film, and conductive molded article. Can do. Moreover, the said carbon nanofiber is suitable as a reinforcing material, and can be utilized as a high-strength resin material which raised the mechanical strength by mix | blending with resin.

The carbon nanofiber of the present invention is selected from, for example, one or more selected from oxides of Fe, Ni, Co, Mn, and Cu as catalyst particles, and oxides of Mg, Ca, Al, and Si. In addition, one or two or more mixed oxide powders are used, and carbon monoxide or a mixed gas of carbon dioxide and hydrogen is brought into contact with the catalyst particles at a temperature of 400 ° C. to 800 ° C. to produce carbon nanofibers. In the vapor phase growth method, it can be produced by adjusting the catalyst and mixed gas composition. Since the carbon nanofibers produced by the above method have a lipophilic amorphous carbon layer, carbon nanofibers having a DBP oil absorption of 150 ml / 100 g or more can be obtained.

Hereinafter, the present invention will be described based on specific embodiments.
In the present invention, the catalyst particles are one or more selected from oxides of Fe, Ni, Co, Mn, and Cu, and one or two selected from oxides of Mg, Ca, Al, and Si. Vapor phase growth method for producing carbon nanofibers by using the above mixed oxide powder and bringing carbon monoxide and / or a mixed gas of carbon dioxide and hydrogen into contact with the catalyst particles at a temperature of 400 ° C. to 800 ° C. In the method, carbon nanofibers having an amorphous carbon layer having a lipophilic surface are produced by adjusting the composition of the catalyst and the mixed gas.
The carbon nanofiber of the present invention has a DBP oil absorption of 150 ml / 100 g or more , preferably a DBP oil absorption of 200 ml / 100 g, more preferably 300 ml / 100 g or more. Therefore, the carbon nanofibers of the present invention are excellent in resin dispersibility, and even if blended in a larger amount than conventional ones, the original physical properties of the resin are not impaired, and the tensile strength and extensibility are within the practical range. Can be maintained.




Specifically, as shown in the Examples, a resin composition in which 5 wt% of carbon nanofibers having a DBP oil absorption of the present invention of 250 ml / 100 g are blended with PET resin is spun to obtain a single yarn thickness of 8 ( dT / f) conductive yarn can be produced. The conductive yarn has a tensile strength of 3.0 g / dT and an elongation of 15%. As a yarn that is slightly below the original tensile strength and elongation of PET resin. Has sufficient mechanical properties. On the other hand, a resin composition in which 5 wt% of a conventional carbon nanofiber having a DBP oil absorption of 80 ml / 100 g is blended in a PET resin cannot be spun because the original physical properties of the resin are greatly impaired.

Since the carbon nanofibers of the present invention are easily adapted to the resin, for example, the DBP oil absorption is 150 ml / 100 g or more, the volume resistance value of the compact is 1.0 Ωcm or less, the diameter is 5 to 100 nm, and the aspect ratio is 10 or more. In a resin composition in which carbon nanofibers (carbon nanotubes) having a BET specific surface area of 250 m 2 / g or less and having a hollow inside are blended with a resin, the dispersibility is improved even if the amount of carbon nanofibers is less than that of the conventional one. Since it is good, a high conductivity and strength reinforcing effect can be obtained.

Specifically, carbon according to the present invention having a DBP oil absorption of 300 ml / 100 g, a volume resistance value of a compacted body of 5.0 × 10 −2 Ωcm, a diameter of 20 nm, an average spect ratio of about 100, and a BET specific surface area of 400 m 2 / g. A resin composition obtained by blending 4% by weight of nanofibers with PC resin and molded into a PC film with a thickness of 100 μm has a surface resistance of 1 × 10 5 Ω · cm (under 100 V voltage) and a tensile strength of 60 (MPa ), The tensile elongation is 100%. On the other hand, a resin composition in which 5 wt% of conventional carbon nanofibers with a DBP oil absorption of 10 ml / 100 g and a compact body having a volume resistance and a BET specific surface area of the same degree as described above are blended with PC resin has sufficient strength. The sheet could not be formed because no elongation was obtained. The thing using the carbon nanofiber of this invention can have the electroconductivity equivalent to or equivalent to the past even if there are few compounding quantities of a carbon nanofiber.

The carbon nanofiber according to the present invention can be produced at a lower temperature than conventional carbon nanofibers without the need for graphite treatment, and the main body has a crystalline graphite structure and the surface has an amorphous carbon layer. Based on the method, the manufacturing conditions can be adjusted and manufactured.

The above production method is, for example, one or more kinds selected from oxides of Fe, Ni, Co, Mn, and Cu as catalyst particles and one kind selected from oxides of Mg, Ca, Al, and Si. Alternatively, vapor phase growth in which carbon nanofibers are produced by using two or more mixed oxide powders and contacting carbon monoxide or a mixed gas of carbon dioxide and hydrogen with the catalyst particles at a temperature of 400 ° C. to 800 ° C. Is the law.

In the above production method, specifically, the catalyst was selected from Group VIIa, Group VII I, Group Ib (transition metal) element oxides, particularly oxides of Fe, Ni, Co, Mn, and Cu. A mixed oxide powder composed of one or more kinds and one or more kinds of oxides of Mg, Ca, Al, and Si is used. These metal oxide powders may be mixed powders, composite powders, or solid solution powders.

Among the above metal oxide powders, a mixed powder of Co oxide and Mg oxide or a powder in which the Mg oxide surface is coated with Co oxide, more preferably a mixed powder of Co 3 O 4 and MgO or an MgO surface Is preferably a powder coated with Co 3 O 4 . The weight ratio (Co oxide / Mg oxide) of the mixed powder composed of Co oxide and Mg oxide is suitably 90/10 to 10/90, and preferably 80/20 to 50/50.

The size of the catalyst particles is such that the average primary particle diameter is in the range of 1 nm to 1 μm, preferably 5 nm to 100 nm. Usually, the fine powder having such a particle size may be aggregated to form aggregated particles of about 100 μm. However, even the aggregated particles have no significant influence on the reaction because the gas penetrates the particle surface. In order to improve the handling property of the catalyst particles, the particle size is preferably in the range of 100 nm to 50 μm. The catalyst particles are arranged on a substrate such as quartz as a fiber growth nucleus. The catalyst particles may be arranged on the substrate as long as the catalyst particles are uniformly shaken on the boat. Alternatively, the catalyst particles may be suspended in a solvent such as alcohol to prepare a suspension, and the suspension may be sprayed on a substrate and dried to be uniformly disposed on the boat.

Polycrystalline graphite nanofibers are grown by bringing the raw material gas into contact with the catalyst particles and reacting them at a temperature of 450 to 800 ° C. under a pressure of 0.08 to 10 MPa in a reaction chamber. In the gas phase synthesis of carbon nanofibers, it is necessary to sufficiently stabilize the synthesis atmosphere in advance. Therefore, it is desirable to start heating after introducing an inert gas containing about 10% of hydrogen into the reaction chamber to replace the synthesis atmosphere, and to maintain the synthesis temperature for about 1 to 2 hours.

After bringing the temperature and atmosphere in the reaction chamber to a steady state, the raw material gas is introduced, brought into contact with the catalyst particles, and the raw material gas is thermally decomposed to grow graphite. As the source gas, carbon monoxide and / or a mixed gas of carbon dioxide and hydrogen can be used. The mixing volume ratio (CO / H 2 ) of H 2 to CO and / or CO 2 in the mixed gas is suitably 20/80 to 99/1, preferably 50/50 to 99/1. This raw material gas is supplied, for example, for 0.01 to 24 hours to grow carbon nanofibers from the catalyst particles.

In the above production method, in order to obtain carbon nanofibers having a high DBP oil absorption, the combination of catalyst particles and the raw material gas composition are adjusted, and the reaction is preferably performed with hydrogen gas after the reaction. Specifically, as a catalyst, a mixed powder of Co oxide and Mg oxide or a powder in which the surface of Mg oxide is coated with Co oxide, more preferably a mixed powder of Co 3 O 4 and MgO or the surface of MgO is used. Using a powder coated with Co 3 O 4 , using a carbon source that does not contain hydrocarbons, specifically using carbon monoxide and / or carbon dioxide, setting the synthesis temperature to 550 ° C. to 650 ° C. By adjusting the CO / H2 ratio of the mixed gas to 50/50 to 99/1 and continuously treating with hydrogen gas for 10 minutes or more under the same temperature as the reaction temperature after the reaction, the DBP oil absorption is 150 ml / 100 g or more. The carbon nanofiber can be produced.

As an apparatus for performing the above manufacturing method, a heat treatment furnace 20 shown in FIG. 1 can be used. The heat treatment furnace 20 has an apparatus main body 21 made of a heat insulating material, and a gas flow path 27 penetrating the center of the apparatus is formed inside the main body 21 by partitioning with two partition plates 26. A heating element 22 is installed so as to surround the path 27. As the heating element 22, an incandescent lamp, a halogen lamp, an arc lamp, a graphite heater, or the like can be used. One opening of the gas flow path 27 is a gas supply port 24, and the other opening is a gas discharge port 29. A substrate 28 is placed on the extraction table 31 in the gas flow path 27.

After the catalyst powder 32 is placed on the substrate 28, the substrate 28 is taken out and placed on the stand 31 and stored in the gas flow path of the heat treatment furnace 20. Subsequently, the pressure of the heat treatment furnace 20 is controlled within a range of 0.08 to 10 MPa, a raw material mixed gas is introduced from the supply port 24, and the inside of the furnace is heated to 450 ° C. to 800 ° C., preferably 550 ° C. by the heating element 22. It is heated to ˜650 ° C., the raw material gas is brought into contact with the catalyst particles and reacted, and graphite is grown to form carbon nanofibers 33.

Since the catalyst remains in the produced carbon nanofibers, the catalyst particles are removed by dipping in an acidic solution such as nitric acid, hydrochloric acid, or hydrofluoric acid. In addition, you may use it in the state made to carry | support the catalyst particle as it is in carbon fiber.

Examples of the present invention are shown below together with comparative examples.
[Examples 1-5, Comparative Examples 1-3]
Carbon nanofibers were synthesized under the conditions shown in Table 1 using the heat treatment furnace shown in FIG. About this carbon nanofiber, DBP oil absorption and resistivity were measured. The resistivity was determined by pressing carbon nanofibers at a pressure of 100 kg / cm 2 and measuring the resistance value by the four probe method. Further, the produced carbon nanofiber was blended with a resin to form a resin composition, and this resin composition was spun by a melt spinning method to obtain a multifilament having a thickness of 380 dT / 48f. Table 2 shows the volume resistance, surface state, strength, and elongation of the obtained yarn.

As shown in the results of Table 1, the DBP oil absorption amount of the carbon nanofibers is different by adjusting the catalyst and the raw material gas composition. Specifically, a mixed powder of Co 3 O 4 and MgO was used as a catalyst, a mixed gas of carbon monoxide and hydrogen was used as a raw material gas, and the mixing ratio was changed. On the other hand, as a comparative example, an iron nickel metal powder-supported alumina catalyst is used and a mixed gas of ethylene gas and carbon monoxide is used as a raw material gas. As shown in the results of Table 2, the physical properties of the resin composition containing carbon nanofibers vary greatly depending on the DBP oil absorption of the carbon nanofibers.

Schematic cross-sectional view showing the carbon nanofiber production apparatus of the present invention

Explanation of symbols

20-heat treatment furnace, 21-device main body, 22-heating element, 24-supply port, 26-partition plate, 27-gas flow path, 28-substrate, 29-discharge port, 31-extraction stand, 32-catalyst powder, 33-carbon nanofiber.

Claims (2)

  1. One or more selected from oxides of Fe, Ni, Co, Mn and Cu as catalyst particles and one or more mixed oxidations selected from oxides of Mg, Ca, Al and Si In the vapor phase growth method for producing carbon nanofibers by using carbon powder and contacting carbon monoxide and / or a mixed gas of carbon dioxide and hydrogen with the catalyst particles at a temperature of 400 ° C. to 800 ° C. A method of producing a carbon nanofiber having an amorphous carbon layer having a lipophilic surface by adjusting a mixed gas composition.
  2. 2. The manufacturing method according to claim 1, wherein a mixed powder of Co 3 O 4 and MgO or a powder whose surface of MgO is coated with Co 3 O 4 is used as a catalyst, and the CO / H 2 ratio of the raw material mixed gas is 50/50. A method for producing carbon nanofibers having a DBP oil absorption of 150 ml / 100 g or more by adjusting to ~ 99/1 and treating with hydrogen gas for 10 minutes or more continuously at the same temperature as the reaction temperature after the reaction.
JP2004345423A 2004-11-30 2004-11-30 Method for producing carbon nanofibers with excellent dispersibility in resin Active JP4565384B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004345423A JP4565384B2 (en) 2004-11-30 2004-11-30 Method for producing carbon nanofibers with excellent dispersibility in resin

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004345423A JP4565384B2 (en) 2004-11-30 2004-11-30 Method for producing carbon nanofibers with excellent dispersibility in resin

Publications (2)

Publication Number Publication Date
JP2006152490A JP2006152490A (en) 2006-06-15
JP4565384B2 true JP4565384B2 (en) 2010-10-20

Family

ID=36631111

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004345423A Active JP4565384B2 (en) 2004-11-30 2004-11-30 Method for producing carbon nanofibers with excellent dispersibility in resin

Country Status (1)

Country Link
JP (1) JP4565384B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2838837A4 (en) * 2012-04-16 2015-12-23 Seerstone Llc Methods and structures for reducing carbon oxides with non-ferrous catalysts
US9505622B2 (en) 2011-09-30 2016-11-29 Mitsubishi Materials Corporation Carbon nanofibers encapsulating metal cobalt, and production method therefor

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5051571B2 (en) * 2006-11-30 2012-10-17 三菱マテリアル株式会社 Conductive fiber and its use
JP5131426B2 (en) * 2006-11-30 2013-01-30 三菱マテリアル株式会社 Carbon nanofiber dispersed polyimide varnish and coating film thereof
JP5194455B2 (en) * 2007-01-22 2013-05-08 三菱化学株式会社 Catalyst for producing vapor grown carbon fiber and vapor grown carbon fiber
FR2933237B1 (en) * 2008-06-25 2010-10-29 Commissariat Energie Atomique Architecture of horizontal interconnections based on carbon nanotubes.
JP5621230B2 (en) * 2009-09-07 2014-11-12 宇部興産株式会社 Fine carbon fiber and method for producing the same
JP5552834B2 (en) * 2010-02-23 2014-07-16 学校法人 東洋大学 Method for producing carbon nanotube
CN104284861A (en) 2012-04-16 2015-01-14 赛尔斯通股份有限公司 Methods for treating offgas containing carbon oxides
NO2749379T3 (en) 2012-04-16 2018-07-28
JP5978824B2 (en) * 2012-07-20 2016-08-24 宇部興産株式会社 Fine carbon dispersion, method for producing the same, electrode paste using the same, and electrode for lithium ion battery
JP5708738B2 (en) * 2013-09-04 2015-04-30 三菱化学株式会社 Aggregate of fine hollow carbon fibers and method for producing aggregate of fine hollow carbon fibers
CN105980301B (en) 2014-02-05 2018-03-06 电化株式会社 The manufacture method and carbon nano-fiber of carbon nano-fiber
JPWO2017022553A1 (en) 2015-07-31 2018-05-17 デンカ株式会社 Method for producing carbon nanofiber
EP3512012A4 (en) 2016-09-07 2019-09-04 Denka Company Ltd Conductive composition for electrodes, and electrode and battery using same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004075848A (en) * 2002-08-19 2004-03-11 Asahi Glass Co Ltd Conductive fluoro-copolymer composition and laminate using the same
JP2004300631A (en) * 2003-03-31 2004-10-28 Mitsubishi Materials Corp Carbon nanofiber and method for producing the same
JP2004299986A (en) * 2003-03-31 2004-10-28 Mitsubishi Materials Corp Carbon nanotube, and its production method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004075848A (en) * 2002-08-19 2004-03-11 Asahi Glass Co Ltd Conductive fluoro-copolymer composition and laminate using the same
JP2004300631A (en) * 2003-03-31 2004-10-28 Mitsubishi Materials Corp Carbon nanofiber and method for producing the same
JP2004299986A (en) * 2003-03-31 2004-10-28 Mitsubishi Materials Corp Carbon nanotube, and its production method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9505622B2 (en) 2011-09-30 2016-11-29 Mitsubishi Materials Corporation Carbon nanofibers encapsulating metal cobalt, and production method therefor
EP2838837A4 (en) * 2012-04-16 2015-12-23 Seerstone Llc Methods and structures for reducing carbon oxides with non-ferrous catalysts
US9796591B2 (en) 2012-04-16 2017-10-24 Seerstone Llc Methods for reducing carbon oxides with non ferrous catalysts and forming solid carbon products

Also Published As

Publication number Publication date
JP2006152490A (en) 2006-06-15

Similar Documents

Publication Publication Date Title
Singh et al. Production of controlled architectures of aligned carbon nanotubes by an injection chemical vapour deposition method
De Jong et al. Carbon nanofibers: catalytic synthesis and applications
Pan et al. Oriented silicon carbide nanowires: synthesis and field emission properties
Liu et al. A study of the electrical properties of carbon nanotube-NiFe2O4 composites: Effect of the surface treatment of the carbon nanotubes
Kumar et al. Chemical vapor deposition of carbon nanotubes: a review on growth mechanism and mass production
US7871591B2 (en) Methods for growing long carbon single-walled nanotubes
JP5937653B2 (en) Carbon material and manufacturing method thereof
Peigney et al. Carbon nanotubes grown in situ by a novel catalytic method
US6986877B2 (en) Method for preparing nano-carbon fiber and nano-carbon fiber
US6911260B2 (en) Reinforced carbon nanotubes
Ajayan et al. Nanometre-size tubes of carbon
US6514897B1 (en) Carbide and oxycarbide based compositions, rigid porous structures including the same, methods of making and using the same
JP5436528B2 (en) Carbon nanotubes on carbon nanofiber substrate
US8562937B2 (en) Production of carbon nanotubes
US7157068B2 (en) Varied morphology carbon nanotubes and method for their manufacture
Inagaki New carbons-control of structure and functions
Awasthi et al. Synthesis of carbon nanotubes
JP2009120836A (en) Conductive polyolefin with good mechanical characteristics
CA2471603C (en) Iron/carbon composite, carbonaceous material comprising the iron/carbon composite, and process for producing the same
CA2600311C (en) Composite material
Merchan-Merchan et al. Combustion synthesis of carbon nanotubes and related nanostructures
US20030147802A1 (en) Process for making single-wall carbon nanotubes utilizing refractory particles
Zhang et al. Pressureless sintering of carbon nanotube–Al2O3 composites
Qian et al. Non-catalytic CVD preparation of carbon spheres with a specific size
US20060025515A1 (en) Nanotube composites and methods for producing

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20071031

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20100524

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100526

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100630

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20100721

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20100722

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130813

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250