U.S. patent application number 12/657507 was filed with the patent office on 2010-05-27 for carbon nanotube yarn and method for making the same.
This patent application is currently assigned to Tsinghua University. Invention is credited to Shou-Shan Fan, Kai-Li Jiang.
Application Number | 20100129654 12/657507 |
Document ID | / |
Family ID | 38165110 |
Filed Date | 2010-05-27 |
United States Patent
Application |
20100129654 |
Kind Code |
A1 |
Jiang; Kai-Li ; et
al. |
May 27, 2010 |
Carbon nanotube yarn and method for making the same
Abstract
A carbon nanotube yarn includes a number of carbon nanotube yarn
strings bound together, and each of the carbon nanotube yarn
strings includes a number of carbon nanotube bundles that are
joined end to end by van der Waals attractive force, and each of
the carbon nanotube bundles includes a number of carbon nanotubes
substantially parallel to each other. A method for making the
carbon nanotube yarn includes soaking the at least one carbon
nanotube yarn string drawn out from a carbon nanotube array in an
organic solvent to shrink it and then collecting it.
Inventors: |
Jiang; Kai-Li; (Beijing,
CN) ; Fan; Shou-Shan; (Beijing, CN) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
Tsinghua University
Beijing City
CN
HON HAI Precision Industry CO., LTD.
Tu-Cheng City
TW
|
Family ID: |
38165110 |
Appl. No.: |
12/657507 |
Filed: |
January 21, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11586976 |
Oct 26, 2006 |
|
|
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12657507 |
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Current U.S.
Class: |
428/367 ;
423/447.1; 423/447.2; 977/742; 977/842 |
Current CPC
Class: |
D02G 3/16 20130101; D01F
9/127 20130101; B82Y 30/00 20130101; D10B 2101/122 20130101; Y10T
428/2918 20150115 |
Class at
Publication: |
428/367 ;
423/447.1; 423/447.2; 977/742; 977/842 |
International
Class: |
B32B 5/00 20060101
B32B005/00; B32B 9/00 20060101 B32B009/00; D01F 9/12 20060101
D01F009/12 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 16, 2005 |
CN |
200510120716.6 |
Claims
1. A method for making a carbon nanotube yarn, the method
comprising the steps of: (1) providing a carbon nanotube array; (2)
drawing out at least one carbon nanotube yarn string from the
carbon nanotube array; (3) treating the at least one carbon
nanotube yarn string using an organic solvent in a manner such that
the at least one carbon nanotube yarn string is formed into a
single strand of carbon nanotube yarn.
2. The method as claimed in claim 1, wherein the carbon nanotube
array is manufactured using a chemical vapor deposition method.
3. The method as claimed in claim 1, wherein the carbon nanotube
array is a super-aligned carbon nanotube array.
4. The method as claimed in claim 1, wherein the at least one
carbon nanotube yarn string is drawn out from the carbon nanotube
array using tweezers.
5. The method as claimed in claim 1, wherein the at least one
carbon nanotube yarn string comprises a plurality of carbon
nanotube bundles which are joined end to end by van der Waals
attractive force, and each of the carbon nanotube bundles comprises
a plurality of carbon nanotubes substantially parallel to each
other.
6. The method as claimed in claim 1, wherein in step (3), the at
least one carbon nanotube yarn string is soaked in the organic
solvent thereby forming the at least one carbon nanotube yarn
string into a single strand of carbon nanotube yarn.
7. The method as claimed in claim 1, wherein the organic solvent is
a volatilizable organic solvent.
8. The method as claimed in claim 7, wherein the volatilizable
organic solvent is selected from the group consisting of ethanol,
methanol, acetone, dichloroethane, chloroform, and any combination
thereof.
9. A carbon nanotube yarn comprising: a plurality of carbon
nanotube yarn strings juxtaposedly attached to each other, the
carbon nanotube yarn strings each comprising a plurality of carbon
nanotube bundles which are joined end to end by van der Waals
attractive force, and each of the carbon nanotube bundles
comprising a plurality of carbon nanotubes substantially parallel
to each other.
10. The carbon nanotube yarn as claimed in claim 9, wherein a
diameter of the carbon nanotube yarn is in a range from 20 to 30
microns.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 11/586976, filed on Oct. 26, 2006, entitled,
"CARBON NANOTUBE YARN AND METHOD FOR MAKING THE SAME".
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates to nanotubes, and more
particularly to a carbon nanotube yarn and method for making the
same.
[0004] 2. Description of Related Art
[0005] Carbon nanotubes are tubules of carbon generally having a
length of 5 to 100 micrometers and a diameter of 5 to 100
nanometers. Carbon nanotubes can be composed of a number of
co-axial cylinders of graphite sheets and have recently attracted a
great deal of attention for use in different fields such as field
emitters, gas storage and separation, chemical sensors and high
strength composites. However, carbon nanotubes are almost never
used in microscopic applications at present as it is very difficult
to manipulate the carbon nanotubes as a microscopic level. So,
assembling carbon nanotubes into macroscopic structures is of great
importance to their applications at the macroscopic level.
[0006] That a long macroscopic carbon nanotube yarn can be drawn
out from a super-aligned carbon nanotube array has been disclosed
in U.S. Pat. No. 7,045,108. The carbon nanotube yarn includes a
plurality of carbon nanotube bundles that are joined end to end by
van der Waals attractive force, and each of the carbon nanotube
bundles includes a plurality of carbon nanotubes substantially
parallel to each other. Referring to FIG. 7, a simple model of a
continued carbon nanotube yarn 14 being drawn out from a
super-aligned carbon nanotube array 10 is shown. A number of carbon
nanotube bundles 12 are joined end to end by van der Waals
attractive force to form the continued carbon nanotube yarn 14.
However, in general, the carbon nanotube yarn 14 is several
centimeters in length and several microns in thickness. A ratio of
surface area to volume of the carbon nanotube yarn 14 is very
great, and the surface of it is very clean, so it is very sticky
and as such macroscopic level application of the carbon nanotube
yarn 14 is restricted to a great extent.
SUMMARY
[0007] A carbon nanotube yarn and method for making the same
according to a preferred embodiment is provided.
[0008] The method includes the steps of: [0009] (1) providing a
carbon nanotube array; [0010] (2) drawing out at least one carbon
nanotube yarn string from the carbon nanotube array; [0011] (3)
treating the at least one carbon nanotube yarn string using an
organic solvent in a manner such that the at least one carbon
nanotube yarn string is formed into a single strand of carbon
nanotube yarn.
[0012] The carbon nanotube yarn includes at least one carbon
nanotube yarn string juxtaposedly attached to each other, the at
least one carbon nanotube yarn string includes a number of carbon
nanotube bundles which are joined end to end by van der Waals
attractive force, and each of the carbon nanotube bundles includes
a number of carbon nanotubes substantially parallel to each
other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Many aspects of the present carbon nanotube yarn and method
for making the same can be better understood by reference to the
following description of embodiments thereof taken in conjunction
with the accompanying drawings.
[0014] FIG. 1 is a schematic view of a device for making a carbon
nanotube yarn in accordance with a preferred embodiment of the
present invention;
[0015] FIG. 2 is a scan electronic microscopy (SEM) photograph of a
carbon nanotube yarn string;
[0016] FIG. 3 is an enlarged sectional view of a tube with a
through hole of the device of FIG. 1;
[0017] FIG. 4 is an enlarged sectional view of a tube connecting
and coupling to a rod;
[0018] FIG. 5 is an enlarged sectional view of a tube connecting
and coupling to two rods;
[0019] FIG. 6 is a SEM photograph of a carbon nanotube yarn of a
preferred embodiment of the present invention; and
[0020] FIG. 7 is schematic view of a conventional carbon nanotube
yarn being drawn out from a carbon nanotube array.
[0021] The exemplifications set out herein illustrate at least one
preferred embodiment of the present carbon nanotube yarn and method
for making the same, in one form, and such exemplifications are not
to be construed as limiting the scope of the invention in any
manner.
DETAILED DESCRIPTION
[0022] Reference will now be made to the drawings to describe in
detail the preferred embodiments of the present carbon nanotube
yarn and method for making the same, in detail.
[0023] Referring to FIG. 1, a method for making carbon nanotube
yarn includes the steps of: [0024] (1) providing a carbon nanotube
array 20; [0025] (2) drawing out a number of carbon nanotube yarn
strings 22 from the carbon nanotube array 20; [0026] (3) treating
the number of carbon nanotube yarn strings 22 using an organic
solvent 50 in a manner such that the number of carbon nanotube yarn
strings 22 are formed into a single strand of carbon nanotube yarn
30.
[0027] In the step (1), the carbon nanotube array 20 is generally a
super-aligned carbon nanotube array. The carbon nanotube array 20
can be manufactured using a chemical vapor deposition method. The
method is disclosed in U.S. Pat No. 7,045,108, which is
incorporated herein by reference. For illustrative purposes, the
method for manufacturing the carbon nanotube array 20 is described
below, and includes the steps of: [0028] (a) providing a
substantially flat and smooth substrate, the substrate can be a
p-type or n-type silicon wafer; [0029] (b) depositing a catalyst on
the substrate, the catalyst being selected from the group
consisting of iron, cobalt, nickel or alloys of the same; [0030]
(c) annealing the substrate with the catalyst in protective gas at
300.about.400.degree. C. for about 10 hours; [0031] (d) heating the
annealed substrate with the catalyst to 500.about.700.degree. C.,
supplying a mixture of carbon containing gas and protective gas,
controlling a difference between the local temperature of the
catalyst and the environmental temperature to be at least
50.degree. C., controlling a partial pressure of the carbon
containing gas to be less than 0.2, and growing a number of carbon
nanotubes on the substrate after 5.about.30 minutes such that the
carbon nanotube array 20 is formed on the substrate. The carbon
containing gas can be a hydrocarbon such as acetylene, ethane etc.
The protective gas can be an inert gas or nitrogen gas.
[0032] The superficial density of the carbon nanotube array 20
manufactured by above-described process with carbon nanotube
bundles being compactly bundled up together is higher. The van der
Waals attractive force between adjacent carbon nanotube bundles is
strong, and diameters of the carbon nanotubes are correspondingly
substantial.
[0033] In the step (2), the carbon nanotube yarn strings 22 may be
drawn out from the carbon nanotube array 20 with a tool with a
sharp tip, such as a tweezers. Specifically, an initial carbon
nanotube bundle with a number of carbon nanotubes of the carbon
nanotube array 20 can be drawn out with tweezers. As a carbon
nanotube bundle is drawn out, other carbon nanotube bundles are
also drawn out due to the van der Waals attractive force between
ends of adjacent bundles and a successive carbon nanotube yarn
string 22 is formed. The carbon nanotube yarn string 22 may have a
length of several centimeters and a thickness of several microns.
Referring to FIG. 2, a SEM photograph of the carbon nanotube yarn
string 22 of the present embodiment is shown. In the present
embodiment, a number of carbon nanotube yarn string 22 are drawn
out from the carbon nanotube array 20.
[0034] In the step (3), referring to FIGS. 1 and 3, a device for
continuously soaking the carbon nanotube yarn strings 22 is shown.
The device includes a container 40 for containing the organic
solvent 50 therein, a tube 42 and a vessel 60 configured for
collecting the organic solvent. The tube 42 is coupled to a bottom
of the container 40 and is in communication with the container 40.
The tube has a through hole 44 defined therein for allowing the
carbon nanotube yarn strings 22 to pass therethrough. The container
40 is configured for supplying the organic solvent 50 to the tube
42. A method for soaking the carbon nanotube yarn strings 22 in the
organic solvent 50 thereby shrinking the carbon nanotube yarn
strings 22 into a single strand of carbon nanotube yarn 30 using
above-described device is described below, which includes the steps
in no particular order of: [0035] (a) placing the container 40
above the carbon nanotube yarn strings 22, the container 40
containing the organic solvent 50 for treating the carbon nanotube
yarn strings 22; [0036] (b) supplying the organic solvent 50 to the
tube 42, wherein the organic solvent 50 may be a volatilizable
organic solvent such as ethanol, methanol, acetone, dichloroethane
or chloroform; [0037] (c) placing the vessel 60 below the through
hole 44 of the tube 42 for collecting leaking organic solvent;
[0038] (d) passing the carbon nanotube yarn strings 22 through the
through hole 44 of the tube 42 continuously to soak the carbon
nanotube yarn strings 22 in the organic solvent 50, thereby
shrinking the carbon nanotube yarn strings 22 into the carbon
nanotube yarn 30 with a diameter of 20.about.30 microns under the
action of surface tension of the organic solvent 50. FIG. 6 shows a
SEM photograph of the carbon nanotube yarn 30 of the present
embodiment.
[0039] Alternatively, the tube 42 can have no through hole 44
defined therein, and it can be connected and coupled to a rod. FIG.
4 shows that the tube 42 is connected and coupled to a rod 92. The
organic solvent 50 can flow along surface of the rod 92 and the
carbon nanotube yarn strings 22 can be attached over or below the
rod 92, thereby the carbon nanotube yarn strings 22 shrink into the
carbon nanotube yarn 30 due to the surface tension of the organic
solvent 50.
[0040] Of course, the tube 42 can also be connected and coupled to
more than one rod, and the more than one rod align together in a
parallel form. Referring to FIG. 5, that the tube 42 being
connected and coupled to two rods 94 is shown. The organic solvent
50 can flow along surface of the rods 94 and the carbon nanotube
yarn strings 22 can be attached over or below the rods 94, thereby
the carbon nanotube yarn strings 22 shrink into the carbon nanotube
yarn 30 due to the surface tension of the organic solvent 50.
[0041] The carbon nanotube yarn 30 includes a number of carbon
nanotube yarn strings packed closely together, and each of the
carbon nanotube yarn strings includes a number of carbon nanotube
bundles which are joined end to end by van der Waals attractive
force, and each of the carbon nanotube bundles includes a number of
carbon nanotubes substantially parallel to each other. The ratio of
surface area to volume of the carbon nanotube yarn 30 is low and
the carbon nanotube yarn 30 therefore has non-stick properties.
[0042] The carbon nanotube yarn 30 can be coiled onto a bobbin 80
with a electromotor 70 or by hand.
[0043] Alternatively, the carbon nanotube yarn strings 22 can be
soaked by directly soaking the entire carbon nanotube yarn strings
22 in an organic solvent 50, a shrunk carbon nanotube yarn 30 can
be obtained after the soaked carbon nanotube yarn strings 22 are
pulled out from the solvent under the action of surface tension of
the organic solvent 50. Of course, just one carbon nanotube yarn
string drawn out from the carbon nanotube array 20 can be shrunk
into a carbon nanotube yarn 30 with above-described steps.
[0044] While the present invention has been described as having
preferred or exemplary embodiments, the embodiments can be further
modified within the spirit and scope of this disclosure. This
application is therefore intended to cover any variations, uses, or
adaptations of the embodiments using the general principles of the
invention as claimed. Furthermore, this application is intended to
cover such departures from the present disclosure as come within
known or customary practice in the art to which the invention
pertains and which fall within the limits of the appended claims or
equivalents thereof.
* * * * *