U.S. patent application number 13/043478 was filed with the patent office on 2012-02-23 for marco-scale carbon nanotube tube structure.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to SHOU-SHAN FAN, YANG WEI.
Application Number | 20120045645 13/043478 |
Document ID | / |
Family ID | 45593126 |
Filed Date | 2012-02-23 |
United States Patent
Application |
20120045645 |
Kind Code |
A1 |
WEI; YANG ; et al. |
February 23, 2012 |
MARCO-SCALE CARBON NANOTUBE TUBE STRUCTURE
Abstract
A macro-scale carbon nanotube tube structure is provided. The
carbon nanotube tube structure is a tube-shaped structure. The
tube-shaped structure includes a plurality of carbon nanotubes
combined with each other by van der Waals force. The carbon
nanotubes are substantially parallel to the outer surface of the
tube-shaped structure, and substantially spirally arranged around a
linear axis of the tube-shaped structure by van der Waals force
therebetween.
Inventors: |
WEI; YANG; (Beijing, CN)
; FAN; SHOU-SHAN; (Beijing, CN) |
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
Tu-Cheng
TW
Tsinghua University
Beijing
CN
|
Family ID: |
45593126 |
Appl. No.: |
13/043478 |
Filed: |
March 9, 2011 |
Current U.S.
Class: |
428/368 ;
428/367; 977/742 |
Current CPC
Class: |
C01B 32/16 20170801;
Y10T 428/292 20150115; Y10T 428/2918 20150115; D01F 9/12 20130101;
D01D 5/24 20130101 |
Class at
Publication: |
428/368 ;
428/367; 977/742 |
International
Class: |
B32B 1/08 20060101
B32B001/08; C01B 31/00 20060101 C01B031/00; B32B 9/00 20060101
B32B009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 23, 2010 |
CN |
201010259929.8 |
Claims
1. A macro-scale carbon nanotube tube structure having a
tube-shaped structure, and comprising a plurality of carbon
nanotubes combined with each other by van der Waals force
therebetween.
2. The macro-scale carbon nanotube tube structure of claim 1,
wherein the carbon nanotubes are substantially parallel to an outer
surface of the tube-shaped structure.
3. The macro-scale carbon nanotube tube structure of claim 1,
wherein a cross-section of an inner wall of the tube-shaped
structure is rectangular, trapezoid shaped, circle shaped, or
ellipse shaped.
4. The macro-scale carbon nanotube tube structure of claim 1,
wherein the carbon nanotubes are substantially spirally arranged
around a linear axis of the tube-shaped structure by van der Waals
force therebetween.
5. The macro-scale carbon nanotube tube structure of claim 4,
wherein the carbon nanotubes are entangled with each other or
oriented along one or more directions.
6. The macro-scale carbon nanotube tube structure of claim 4,
wherein the carbon nanotubes substantially spirally extend along an
extending direction of the tube-shaped structure.
7. The macro-scale carbon nanotube tube structure of claim 6,
wherein adjacent carbon nanotubes extending along a same direction
are substantially joined end-to-end by van der Waals force
between.
8. The macro-scale carbon nanotube tube structure of claim 7,
wherein angles defined between the adjacent carbon nanotubes
extending along the same direction and the linear axis of the
tube-shaped structure are substantially equal to each other.
9. The macro-scale carbon nanotube tube structure of claim 4,
further comprising at least one carbon nanotube film spirally
surrounding the linear axis of the tube-shaped structure by van der
Waals force therebetween.
10. The macro-scale carbon nanotube tube structure of claim 4,
further comprising at least one carbon nanotube wire spirally
surrounding the linear axis of the tube-shaped structure by van der
Waals force therebetween.
11. A macro-scale carbon nanotube tube structure having a tube
shaped structure, and comprising a tube wall and having a through
hole defined by the tube wall, wherein the tube wall comprises a
plurality of carbon nanotubes.
12. The macro-scale carbon nanotube tube structure of claim 11,
wherein the tube wall comprises at least one carbon nanotube film
or at least one carbon nanotube wire spirally overlapped by van der
Waals force along an extending direction of the tube shaped
structure.
13. The macro-scale carbon nanotube tube structure of claim 11,
wherein the tube wall comprises a drawn carbon nanotube film or an
untwisted carbon nanotube wire; the carbon nanotube film or the
untwisted carbon nanotube wire comprises a plurality of carbon
nanotubes substantially arranged along a same direction; the
plurality of carbon nanotubes are substantially spirally arranged
along an extending direction of the tube shaped structure.
14. The macro-scale carbon nanotube tube structure of claim 11,
wherein the tube wall comprises a flocculated carbon nanotube film,
the flocculated carbon nanotube film comprises a plurality of
carbon nanotubes entangled with each other and substantially
parallel to an outline of the tube shaped structure.
15. The macro-scale carbon nanotube tube structure of claim 11,
wherein the tube wall comprises a pressed carbon nanotube film; the
pressed carbon nanotube film comprises a plurality carbon nanotubes
resting upon each other and substantially arranged along an
extending direction of the tube-shaped structure; adjacent carbon
nanotubes are substantially attracted to each other and combined by
van der Waals force; an angle between a primary alignment direction
of the carbon nanotubes and a surface of the conductive thread
structure is about 0 degrees to about 15 degrees.
16. The macro-scale carbon nanotube tube structure of claim 11,
wherein an outline of a cross section of the tube wall along a
direction substantially perpendicular to the extending direction of
the tube-shaped structure is rectangular, trapezoid shaped, circle
shaped, or ellipse shaped.
17. A macro-scale carbon nanotube tube structure being a tube
shaped structure, the tube shaped structure comprising at least one
carbon nanotube film or at least one carbon nanotube wire spiraling
upwards along an extending direction of the tube shaped structure
by van der Waals force.
Description
RELATED APPLICATIONS
[0001] This application claims all benefits accruing under 36
U.S.C. .sctn.119 from China Patent Application No. 201010259929.8,
filed on Aug. 23, 2010 in the China Intellectual Property Office,
the disclosure of which is incorporated herein by reference. This
application is related to applications entitled "CARBON NANOTUBE
WIRE STRUCTURE AND METHOD FOR MAKING THE SAME," with application
Ser. No. 12/978,548, filed on Dec. 25, 2010; "APPARATUS FOR MAKING
CARBON NANOTUBE COMPOSITE WIRE STRUCTURE," with application Ser.
No. 12/979,519, filed on Dec. 28, 2010; "CARBON NANOTUBE COMPOSITE
WIRE STRUCTURE AND METHOD FOR MAKING THE SAME," with application
Ser. No. 12/979,454, filed on Dec. 28, 2010, and "CARBON NANOTUBE
COMPOSITE TUBE STRUCTURE AND METHOD FOR MAKING THE SAME," filed
______ (Atty. Docket No. US34823).
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates to a macro-scale carbon
nanotube tube structure and a method for making the macro-scale
carbon nanotube tube structure.
[0004] 2. Discussion of Related Art
[0005] Carbon nanotubes can be composed of a plurality of coaxial
cylinders of graphite sheets. Carbon nanotubes have received a
great deal of interest since the early 1990s. Carbon nanotubes have
interesting and potentially useful electrical and mechanical
properties. Due to these and other properties, carbon nanotubes
have become a significant focus of research and development for use
in electron emitting devices, sensors, transistors, and other
devices.
[0006] Generally, the carbon nanotubes prepared by conventional
methods are in particle or powder forms. The particle or
powder-shaped carbon nanotubes limit the number of carbon nanotube
applications. Thus, preparation of macro-scale carbon nanotube
structures, such as carbon nanotube films, has attracted lots of
attention. The carbon nanotubes wires are solid linear structures,
the carbon nanotube films are sheet-shaped structures. However,
macro-scale carbon nanotube tube structures and methods for making
the same are not provided.
[0007] Therefore, a macro-scale carbon nanotube tube structure and
a method for making the same are provided, to overcome the
above-described shortcomings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Many aspects of the embodiments can be better understood
with references to the following drawings. The components in the
drawings are not necessarily drawn to scale, the emphasis instead
being placed upon clearly illustrating the principles of the
embodiments. Moreover, in the drawings, like reference numerals
designate corresponding parts throughout the several views.
[0009] FIG. 1 shows a scanning electron microscope (SEM) image of
one embodiment of a macro-scale carbon nanotube tube structure.
[0010] FIG. 2 is a cross sectional view of the macro-scale carbon
nanotube tube structure shown in FIG. 1.
[0011] FIG. 3 shows an SEM image of a pressed carbon nanotube film
with the carbon nanotubes therein arranged along a preferred
orientation.
[0012] FIG. 4 shows an SEM image of a flocculated carbon nanotube
film with carbon nanotubes entangled with each other therein.
[0013] FIG. 5 shows an SEM image of a drawn carbon nanotube
film.
[0014] FIG. 6 shows an SEM image of an untwisted carbon nanotube
wire.
[0015] FIG. 7 shows an SEM image of a twisted carbon nanotube
wire.
[0016] FIG. 8 shows a flow chart of one embodiment of a method for
making a macro-scale carbon nanotube tube structure.
[0017] FIG. 9 is a top, partially cut-away view of an apparatus for
making the macro-scale carbon nanotube tube structure shown in FIG.
1.
[0018] FIG. 10 is a front, partially cut-away view of the apparatus
shown in FIG. 9.
DETAILED DESCRIPTION
[0019] The disclosure is illustrated by way of example and not by
way of limitation in the figures of the accompanying drawings. It
should be noted that references to "an" or "one" embodiment in this
disclosure are not necessarily to the same embodiment, and such
references mean at least one.
[0020] Referring to FIG. 1 and FIG. 2, one embodiment of a
macro-scale carbon nanotube tube structure 10 is provided. The
carbon nanotube tube structure 10 is a free-standing tube-shaped
structure. The cross-section of the outline of the carbon nanotube
tube structure 10 along a direction substantially perpendicular to
the carbon nanotube tube structure 10 can be rectangular, trapezoid
shaped, circle shaped, or ellipse shaped. The carbon nanotube tube
structure 10 can include a carbon nanotube layer 12, and a through
hole 14 defined by the carbon nanotube layer 12. An inner wall of
the carbon nanotube layer 12 surrounds the through hole 14. The
carbon nanotube layer 12 can include a plurality of carbon
nanotubes 122. The carbon nanotube layer 12 and the through hole 14
has a common linear axis 142. The carbon nanotubes 122 uniformly
surround the axis 142 and are tightly combined by van der Waals
force therebetween. The carbon nanotubes 122 are substantially
parallel to the outer surface of the carbon nanotube tube structure
10.
[0021] The cross section of the outline of the through hole 14
along a direction substantially perpendicular to the carbon
nanotube tube structure 10, can be rectangular, trapezoid shaped,
circle shaped, or ellipse shaped. The cross-section of the inner
wall of the carbon nanotube tube structure 10 can be rectangular,
trapezoid shaped, circle shaped, or ellipse shaped. It can be noted
that the shape of the through hole 14 can be selected as desired.
The through hole 14 can be substantially defined in the center of
the carbon nanotube layer 12. The thickness of the carbon nanotube
layer 12 can be substantially the same. The carbon nanotube tube
structure 10 is formed by at least one carbon nanotube film or at
least one carbon nanotube wire closely surrounding the through hole
14. The carbon nanotube layer 12 is the wall of the carbon nanotube
tube structure 10, such that at least one carbon nanotube film or
at least one carbon nanotube wire forms the wall. Therefore, the
thickness of the carbon nanotube layer 12 can be controlled by the
layers that surround the through hole 14 of the at least one carbon
nanotube film or at least one carbon nanotube wire. In one
embodiment, the effective diameter of an inner wall of the carbon
nanotube tube structure 10 is larger than 10 micrometers (.mu.m).
In another embodiment, the effective diameter of the inner wall of
the carbon nanotube tube structure 10 is larger than 18 .mu.m.
[0022] The carbon nanotube structure comprises a plurality of
carbon nanotubes and can be orderly or disorderly aligned. The
disorderly aligned carbon nanotubes are carbon nanotubes arranged
along many different directions, such that the number of carbon
nanotubes arranged along each different direction can be almost the
same (e.g. uniformly disordered), and/or entangled with each other.
The orderly aligned carbon nanotubes are carbon nanotubes arranged
in a consistently systematic manner, e.g., most of the carbon
nanotubes are arranged approximately along a same direction or have
two or more sections within each of which the most of the carbon
nanotubes are arranged approximately along a same direction
(different sections can have different directions). The carbon
nanotubes can be single-walled, double-walled, and/or multi-walled
carbon nanotubes. The diameters of the single-walled carbon
nanotubes range from about 0.5 nanometers (nm) to about 50 nm. The
diameters of the double-walled carbon nanotubes range from about 1
nm to about 50 nm. The diameters of the multi-walled carbon
nanotubes range from about 1.5 nm to about 50 nm.
[0023] The free-standing carbon nanotube structure may have a
planar shape or a linear shape. The carbon nanotube structure can
include at least one carbon nanotube film, at least one carbon
nanotube wire structure, or the combination of the carbon nanotube
film and the carbon nanotube wire structure.
[0024] Referring to FIG. 3, the carbon nanotube film can also be a
pressed carbon nanotube film formed by pressing a carbon nanotube
array down on the substrate. The carbon nanotubes in the pressed
carbon nanotube array are arranged along a same direction or along
different directions. The carbon nanotubes in the pressed carbon
nanotube array can rest upon each other. Adjacent carbon nanotubes
are attracted to each other and are combined by van der Waals
force. An angle between a primary alignment direction of the carbon
nanotubes and a surface of the pressed carbon nanotube array is
about 0 degrees to approximately 15 degrees. The greater the
pressure applied, the smaller the angle obtained. If the carbon
nanotubes in the pressed carbon nanotube array are arranged along
different directions, the carbon nanotube structure can be
isotropic. The thickness of the pressed carbon nanotube array can
range from about 0.5 nm to about 1 mm. The length of the carbon
nanotubes can be larger than 50 .mu.m. Clearances can exist in the
carbon nanotube array. Therefore, micropores can exist in the
pressed carbon nanotube array and be defined by the adjacent carbon
nanotubes. Examples of the pressed carbon nanotube film are taught
by US PGPub. 20080299031A1 to Liu et al.
[0025] Referring to FIG. 4, the carbon nanotube film can be a
flocculated carbon nanotube film formed by a flocculating method.
The flocculated carbon nanotube film can include a plurality of
long, curved, disordered carbon nanotubes entangled with each
other. A length of the carbon nanotubes can be greater than 10
centimeters. In one embodiment, the length of the carbon nanotubes
is in a range from about 200 .mu.m to about 900 .mu.m. Further, the
flocculated carbon nanotube film can be isotropic. Here,
"isotropic" means the carbon nanotube film has properties identical
in all directions substantially parallel to a surface of the carbon
nanotube film. The carbon nanotubes can be substantially uniformly
distributed in the carbon nanotube film. The adjacent carbon
nanotubes are acted upon by the van der Waals force therebetween,
thereby forming an entangled structure with micropores defined
therein. The thickness of the flocculated carbon nanotube film can
range from about 1 .mu.m to about 1 mm. In one embodiment, the
thickness of the flocculated carbon nanotube film is about 100
.mu.m.
[0026] Referring to FIG. 5, the carbon nanotube film can also be a
drawn carbon nanotube film formed by drawing a film from a carbon
nanotube array. Examples of the drawn carbon nanotube film are
taught by U.S. Pat. No. 7,045,108 to Jiang et al. The thickness of
the drawn carbon nanotube film can be in a range from about 0.5 nm
to about 100 .mu.m.
[0027] The drawn carbon nanotube film includes a plurality of
carbon nanotubes that are arranged substantially parallel to a
surface of the drawn carbon nanotube film. A large number of the
carbon nanotubes in the drawn carbon nanotube film can be oriented
along a preferred orientation, meaning that a large number of the
carbon nanotubes in the drawn carbon nanotube film are arranged
substantially along the same direction. An end of one carbon
nanotube is joined to another end of an adjacent carbon nanotube
arranged substantially along the same direction by van der Waals
force. A small number of the carbon nanotubes are randomly arranged
in the drawn carbon nanotube film, and has a small if not
negligible effect on the larger number of the carbon nanotubes in
the drawn carbon nanotube film arranged substantially along the
same direction. It can be appreciated that some variation can occur
in the orientation of the carbon nanotubes in the drawn carbon
nanotube film. Microscopically, the carbon nanotubes oriented
substantially along the same direction may not be perfectly aligned
in a straight line, and some curve portions may exist. It can be
understood that contact between some carbon nanotubes located
substantially side by side and oriented along the same direction
cannot be totally excluded.
[0028] More specifically, the drawn carbon nanotube film can
include a plurality of successively oriented carbon nanotube
segments joined end-to-end by van der Waals force therebetween.
Each carbon nanotube segment includes a plurality of carbon
nanotubes substantially parallel to each other, and joined by van
der Waals force therebetween. The carbon nanotube segments can vary
in width, thickness, uniformity and shape. The carbon nanotubes in
the drawn carbon nanotube film are also substantially oriented
along a preferred orientation. The width of the drawn carbon
nanotube film relates to the carbon nanotube array from which the
drawn carbon nanotube film is drawn.
[0029] The carbon nanotube structure can include more than one
drawn carbon nanotube film. An angle can exist between the
orientation of carbon nanotubes in adjacent films, stacked and/or
coplanar. Adjacent carbon nanotube films can be combined by only
the van der Waals force therebetween without the need of an
additional adhesive. An angle between the aligned directions of the
carbon nanotubes in two adjacent drawn carbon nanotube films can
range from about 0 degrees to about 90 degrees. Spaces are defined
between two adjacent carbon nanotubes in the drawn carbon nanotube
film. If the angle between the aligned directions of the carbon
nanotubes in adjacent drawn carbon nanotube films is larger than 0
degrees, the micropores can be defined by the crossed carbon
nanotubes in adjacent drawn carbon nanotube films.
[0030] The carbon nanotube wire structure can also include at least
one carbon nanotube wire. If the carbon nanotube wire structure
includes a plurality of carbon nanotube wires, the carbon nanotube
wires can be substantially parallel to each other to form a
bundle-like structure or twisted with each other to form a twisted
structure. The bundle-like structure and the twisted structure are
two kinds of linear shaped carbon nanotube structures.
[0031] The carbon nanotube wire itself can be untwisted or twisted.
Referring to FIG. 6, treating the drawn carbon nanotube film with a
volatile organic solvent can obtain the untwisted carbon nanotube
wire. In one embodiment, the organic solvent is applied to soak the
entire surface of the drawn carbon nanotube film. During the
soaking, adjacent substantially parallel carbon nanotubes in the
drawn carbon nanotube film will bundle together, due to the surface
tension of the organic solvent as it volatilizes, and thus, the
drawn carbon nanotube film will be shrunk into an untwisted carbon
nanotube wire. The untwisted carbon nanotube wire includes a
plurality of carbon nanotubes substantially oriented along a same
direction (i.e., a direction along the length direction of the
untwisted carbon nanotube wire). The carbon nanotubes are
substantially parallel to the axis of the untwisted carbon nanotube
wire. In one embodiment, the untwisted carbon nanotube wire
includes a plurality of successive carbon nanotubes joined end to
end by van der Waals force therebetween. A length of the untwisted
carbon nanotube wire can be arbitrarily set as desired. A diameter
of the untwisted carbon nanotube wire ranges from about 0.5 nm to
about 100 .mu.m. Examples of the untwisted carbon nanotube wire are
taught by US Patent Application Publication US 2007/0166223 to
Jiang et al.
[0032] Referring to FIG. 7, the twisted carbon nanotube wire can be
obtained by twisting a drawn carbon nanotube film using a
mechanical force to turn the two ends of the drawn carbon nanotube
film in opposite directions. The twisted carbon nanotube wire
includes a plurality of carbon nanotubes helically oriented around
an axial direction of the twisted carbon nanotube wire. In one
embodiment, the twisted carbon nanotube wire includes a plurality
of successive carbon nanotubes joined end to end by van der Waals
force therebetween. The length of the carbon nanotube wire can be
set as desired. A diameter of the twisted carbon nanotube wire can
be from about 0.5 nm to about 100 .mu.m.
[0033] The twisted carbon nanotube wire can be treated with a
volatile organic solvent, before or after being twisted. After
being soaked by the organic solvent, the adjacent substantially
parallel carbon nanotubes in the twisted carbon nanotube wire will
bundle together due to the surface tension of the organic solvent
when the organic solvent volatilizes. The specific surface area of
the twisted carbon nanotube wire will decrease. The density and
strength of the twisted carbon nanotube wire will be increased.
[0034] If the carbon nanotube tube structure 10 includes at least
one flocculated carbon nanotube film, the at least one flocculated
carbon nanotube film can be closely and uniformly combined by van
der Waals force therebetween to form the carbon nanotube layer 12
and define the through hole 14 including the linear axis 142. The
at least one flocculated carbon nanotube film can be spirally
arranged along the linear axis 142. The carbon nanotubes 122 can be
substantially tightly and uniformly arranged around the linear axis
142 by van der Waals force therebetween. The carbon nanotubes 122
are substantially entangled with each other and substantially
parallel to the outline of the carbon nanotube tube structure
10.
[0035] If the carbon nanotube tube structure 10 includes at least
one drawn carbon nanotube film, or at least one untwisted carbon
nanotube wire. The at least one drawn carbon nanotube film or at
least one untwisted carbon nanotube wire can be closely and
uniformly combined by van der Waals force therebetween to form the
carbon nanotube layer 12 and define the through hole 14 having the
linear axis 142, thereby forming the carbon nanotube tube structure
10. Most of the carbon nanotubes 122 can be arranged around the
linear axis 142. Most adjacent carbon nanotubes 122 substantially
extending along the same direction are joined end-to-end by van der
Waals force. Furthermore, most of the carbon nanotubes 122 can
substantially spirally extend along the linear axis 142. Namely,
the most of the carbon nanotubes 122 can substantially spirally
extend along the inner wall of the carbon nanotube tube structure
10. An angle is defined between most of the carbon nanotubes and
the linear axis 142. The angle can be larger than 0 degrees and
less than or equal to 90 degrees. Carbon nanotubes 122 in each
drawn carbon nanotube film or untwisted carbon nanotube wire can
extend along a same direction, such that angles defined between
most of the carbon nanotubes 122 and the linear axis 142 can be
substantially equal to each other.
[0036] If the carbon nanotube tube structure 10 includes at least
one pressed carbon nanotube film, the at least one pressed carbon
nanotube film can be tightly and uniformly combined by van der
Waals force therebetween to form the carbon nanotube layer 12 and
define the through hole 14. The at least one pressed carbon
nanotube film can be substantially spirally coiled around the
through hole 14. If the at least one pressed carbon nanotube film
includes a plurality of disordered carbon nanotubes 122, the carbon
nanotubes 122 can be disorderly, uniformly, and tightly arranged
along the linear axis 142. The at least one pressed carbon nanotube
film includes carbon nanotubes 122 substantially resting upon each
other. The carbon nanotubes 122 can be uniformly and tightly
arranged along the linear axis 142, and adjacent carbon nanotubes
are attracted to each other and combined by van der Waals force. An
angle between a primary alignment direction of the carbon nanotubes
and the linear axis 142 can be about 0 degrees to about 15
degrees.
[0037] If the carbon nanotube tube structure 10 includes at least
one twisted carbon nanotube wire, the at least one twisted carbon
nanotube wire can be tightly and uniformly combined by van der
Waals force therebetween to form the carbon nanotube layer 12 and
define the through hole 14 in the center of the carbon nanotube
layer 12. The at least one twisted carbon nanotube wire can be
spirally arranged around the through hole 14. Most of the carbon
nanotubes 122 are joined end-to-end and uniformly located around
the linear axis 142 by van der Waals force therebetween. That is,
most of the carbon nanotubes 122 are joined end-to-end and
uniformly located around the inner wall of the carbon nanotube tube
structure 10.
[0038] In one embodiment, the carbon nanotube tube structure 10 is
a hollow tube-shaped structure with an inner diameter of about 25
.mu.m and an outer diameter of about 50 .mu.m. The cross-section of
the carbon nanotube tube structure 10 is circle shaped. The carbon
nanotube tube structure 10 includes a plurality of carbon nanotubes
122. The carbon nanotube tubes 122 are tightly combined by van der
Waals force to form the carbon nanotube layer 12 and define the
through hole 14 with the diameter of about 25 .mu.m. The
cross-section of the through hole 14 of the carbon nanotube tube
structure 10 is circle shaped.
[0039] Specifically, six drawn carbon nanotube films spiral upwards
to define the through hole 14, thereby forming the carbon nanotube
tube structure 10. Most of the carbon nanotubes 122 oriented along
a same direction are joined end-to-end by van der Waals force.
[0040] Furthermore, most of the carbon nanotubes 122 spirally
extend along the linear axis 142. An angle (not shown) defined
between most of the carbon nanotubes 122 and the linear axis 142 is
about 45 degrees. In addition, most of the carbon nanotubes 122 in
each drawn carbon nanotube film substantially extend along a same
direction, such that angles defined between most of the carbon
nanotubes 122 and the linear axis 142 are substantially the
same.
[0041] Referring to FIG. 8, one embodiment of a method for making
the carbon nanotube tube structure 10 is provided. The method can
include:
[0042] (a), providing a linear structure and a carbon nanotube
structure including at least one carbon nanotube film, or at least
one carbon nanotube wire;
[0043] (b), winding the carbon nanotube structure around the linear
structure to form a carbon nanotube composite wire structure;
and
[0044] (c), removing the linear structure from the carbon nanotube
composite wire structure.
[0045] In step (a), the linear structure is configured to support
the carbon nanotube structure, therefore the conductive thread
structure should have a certain strength and toughness. In
addition, the linear structure should be easily removed by a
chemical method or a physical method. The material of the
conductive thread structure can be metal, alloy, or plastics. The
cross sectional view of the linear structure along a direction
substantially perpendicular to the linear structure, can be
rectangular, trapezoid shaped, circle shaped, or ellipse
shaped.
[0046] The step (b) can include the following steps: (b1), adhering
one end of the carbon nanotube structure to the linear structure;
and (b2), rotating the linear structure with the carbon nanotube
structure, and simultaneously moving the linear structure or the
carbon nanotube structure along a fixed direction, thereby forming
the carbon nanotube composite wire structure.
[0047] In one embodiment, if the carbon nanotube structure is made
from a carbon nanotube array, the step (a) can be providing a
linear structure and a carbon nanotube array. The step (b) can
include steps: (b1), drawing a drawn carbon nanotube film or
untwisted carbon nanotube wire from the carbon nanotube array;
(b2), adhering the drawn carbon nanotube film or untwisted carbon
nanotube wire to the linear structure; and (b3), rotating the
linear structure with the carbon nanotube array, and simultaneously
moving the linear structure or the carbon nanotube structure along
a fixed direction. The drawn carbon nanotube film or untwisted
carbon nanotube wire can be continuously drawn from the carbon
nanotube array. The carbon nanotube composite wire structure can be
continuously produced.
[0048] The step (b) can further include a step of treating the
carbon nanotube composite wire structure using an organic solvent.
Specifically, the carbon nanotube structure is treated by spreading
the organic solvent on the entire surface of the structure wound
around the linear structure, or immersing the linear structure with
the carbon nanotube structure into the organic solvent. The organic
solvent is volatilizable and can be ethanol, methanol, acetone,
dichloroethane, chloroform, or combinations thereof. After being
soaked by the organic solvent, the carbon nanotube structure can be
compacted and decrease the adhesiveness of the carbon nanotube
structure due to the decrease of the surface tension of the carbon
nanotube structure.
[0049] The step (c) can be performed by a chemical method, or a
physical method, such as a mechanical method. In one embodiment, if
the linear structure is made of an active metal or an alloy
composed of active metals, such as iron, aluminum, or an alloy
thereof, the step (c) can include a step of applying the carbon
nanotube composite wire structure into an acidic liquid to react
the linear structure with the acidic liquid. The acidic liquid can
be nitric acid, sulfuric acid, hydrochloric acid, or other suitable
acidic liquid. If the material of the linear structure is an
inactive metal or an alloy consisting of inactive metals, such as
gold, silver, or an alloy thereof, the step (c) can include a step
of heating the carbon nanotube composite wire structure to
evaporate the linear structure. If the material of the linear
structure is a polymer material, metal, or an alloy, the step (c)
can include a step of pulling the linear structure out from the
carbon nanotube composite wire structure using a stretching device
along the axial direction of the linear structure. Therefore, the
figure and the effective diameter of the linear structure can
dictate the figure and effective diameter of the through hole 14 of
the carbon nanotube tube structure 10. The outline of the carbon
nanotube tube structure 10 can also be decided by the linear
structure.
[0050] In one embodiment, the carbon nanotube structure is made of
at least one drawn carbon nanotube film, at least one untwisted
carbon nanotube wire, or a combination thereof. The carbon nanotube
tube structure can be executed by an apparatus 100 shown in FIG. 9
and FIG. 10. The apparatus 100 can include a supply unit 20, a
wrapping unit 30, and a collecting unit 40. The supply unit 20
supplies a linear structure. The wrapping unit 30 can load at least
one carbon nanotube array (not shown) thereon. A carbon nanotube
structure (not shown) can be drawn from the at least one carbon
nanotube array. The carbon nanotube structure can be at least one
drawn carbon nanotube film, at least one untwisted carbon nanotube
wire, or a combination thereof. The wrapping unit 30 wraps the
carbon nanotube structure around the linear structure, thereby
forming the carbon nanotube composite wire structure. The
collecting unit 40 can drive the linear structure to move along a
fixed direction and collect the carbon nanotube composite wire
structure.
[0051] The supply unit 20 can include a pedestal 22, a guiding
shaft 28, and a bobbin 24. The pedestal 22 is substantially
perpendicular to the supporter 60 by fixing one end of the pedestal
22 with respect to the supporter 60. One end of the guiding shaft
28 is fixed on the pedestal 22, and the other end is suspended. The
guiding shaft 28 is substantially perpendicular to the pedestal 22.
The bobbin 24 is hung on the guiding shaft 28, and can be freely
moved around the guiding shaft 28. The bobbin 24 winds a linear
structure thereon. The linear structure can be a conductive thread
structure or a non-conductive thread structure. The non-conductive
thread structure can be a carbon fiber an artificial fiber such as
Kevlar or a natural fiber. The natural fiber can be spider silk or
silkworm silk. The conductive thread structure can be a metal
thread, an alloy thread, a conductive polymer thread, or a
combination thereof.
[0052] The wrapping unit 30 can be configured to load a carbon
nanotube array with a growing substrate for growing the carbon
nanotube array. The wrapping unit 30 can include a drive mechanism
32, a hollow rotating shaft 34, two bearings 342, two braces 36,
and a face plate 38. The drive mechanism 32 is positioned at one
end of the hollow rotating shaft 34 close to the supply unit 20.
The face plate 38 is located at the other end of the hollow
rotating shaft 34. The two bearings 36 are separately harnessed to
the hollow rotating shaft 34. Each brace 36 couples with a bearing
342 to support the hollow rotating shaft 34.
[0053] The drive mechanism 32 drives the hollow rotating shaft 34
to rotate. The hollow rotating shaft 34 is rotated to allow the
face plate 38 to rotate. The drive mechanism 32 can include a first
motor 322, a first belt pulley 324, a second belt pulley 328, and a
belt 326. The first belt pulley 324 is mounted on the first motor
322. The second belt pulley 328 is separated from the first belt
pulley 324, and mounted on the hollow rotating shaft 34. The belt
326 is harnessed to the first belt pulley 324 and the second belt
pulley 328. The first belt pulley 324 can be rotated under the
first motor 322. The first belt pulley 324 can drive the second
belt pulley 328 to rotate by the belt 328. The second belt pulley
328 drives the hollow rotating shaft 34 to rotate. Therefore, a
speed of the first motor 322 can control a rotating speed of the
hollow rotating shaft 34. The structure of the drive mechanism 32
is not restricted by the above description, provided the drive
mechanism 32 can drive the hollow rotating shaft 34 to rotate.
[0054] The hollow rotating shaft 34 is a tube-shaped structure. The
hollow rotating shaft 34 defines a first axis 344 substantially
overlapping with the linear structure, if the linear structure
passes through the hollow rotating shaft 34. The hollow rotating
shaft 34 can be rotatable clockwise or anti-clockwise around the
first axis 344 by the driving mechanism 32.
[0055] The face plate 38 is harnessed on the hollow rotating shaft
34, such that the face plate 38 can accompany the hollow rotating
shaft 34 to rotate around the first axis 344. The hollow rotating
shaft 34 is driven by the first motor 322 such that the rotating
speed of the face plate 38 is controlled by the speed of the first
motor 322. The shape of the face plate 38 is similar to a frustum
pyramid, such as a triangular frustum pyramid, a quadrangular
frustum pyramid, a pentangular frustum pyramid, a hexangular
frustum pyramid, or a heptangular frustum pyramid. The face plate
38 has a plurality of side faces. A support stage protrudes from
each side face. A plurality of support stages locates the carbon
nanotube array. Each support stage can define an angle with the
first axis of the hollow rotating shaft 34, and faces the
collecting unit 40. A plurality of support stages (not labeled)
uniformly surrounds the hollow rotating shaft 34. In one
embodiment, the shape of the face plate 38 is similar to a
hexangular frustum pyramid. Six support stages protrude from the
side faces of the hexangular frustum pyramid. Each support stage
can define the angle of about 45 degrees with the first axis 344 of
the hollow rotating shaft 34.
[0056] The collecting unit 40 can include a second motor 42, and a
collecting shaft 44 fixed on the second motor 42. The collecting
shaft 44 can be substantially perpendicular to the hollow rotating
shaft 34. The collecting shaft 44 can rotate around a second axis
442 of the collecting shaft 44 under the second motor 42, the
second axis 442 is substantially perpendicular to the first axis
344, such that the linear structure can be driven along a fixed
direction, and the carbon nanotube composite wire structure can be
collected on the collecting shaft 44. Therefore, the second motor
42 can control the rotating speed of the collecting shaft 44. The
second motor 42 can also control the collecting speed of the carbon
nanotube composite wire structure.
[0057] The apparatus 100 can further include two locating elements
50. Each locating element 50 defines a locating hole (not labeled).
The center of the locating hole and the first axis 344 of the
hollow rotation shaft 34 are substantially collinear. The two
locating elements 50 ensure the linear structure is substantially
maintained at a same plane and does not contact the inner wall of
the hollow rotation shaft 34. One locating element 50 is fixed
between the supply unit 20 and the wrapping unit 30, thus the
linear structure is suspended in the hollow rotation shaft 34. The
other locating element 50 is positioned between the wrapping unit
30 and the collecting unit 40, so that the carbon nanotube
composite wire structure made by the apparatus 100 and the linear
structure can substantially stay on the same plane. The number of
the locating elements 50 can be selected as desired.
[0058] Specifically, the method for making the carbon nanotube tube
structure using the apparatus 100 can include the steps:
[0059] S10, providing a linear structure by the supply unit 20;
[0060] S20, passing the linear structure through the wrapping unit
30, and fixing the linear structure on the collecting unit 40;
[0061] S30, providing a carbon nanotube structure by the wrapping
unit 30, and adhering one end of the carbon nanotube structure to
the linear structure;
[0062] S40, rotating the face plate 36 and moving the linear
structure along a fixed direction to wind the carbon nanotube
structure around the linear structure such that a carbon nanotube
composite wire structure is formed; and
[0063] S50, removing the linear structure from the carbon nanotube
composite wire structure.
[0064] The step S10 can include the steps: providing the linear
structure coiled around the bobbin 24; and supporting the bobbin 24
with the linear structure on the guiding shaft 28. The bobbin 24
with the linear structure coiled thereon can be moved around the
guiding shaft 28.
[0065] The step S20 can include the steps: passing a free end of
the linear structure through the hollow rotation shaft 34, and
fixing the free end of the linear structure on the surface of the
collecting shaft 44. In one embodiment, the linear structure will
pass through the two locating holes of the two locating elements 50
in sequence before the linear structure is fixed on the collecting
shaft 44, wherein the linear structure substantially overlaps with
the first axis of the hollow rotating shaft 34.
[0066] The step S30 can include the following sub-steps:
[0067] S31, providing at least one carbon nanotube array, wherein
each carbon nanotube array is grown on a growing substrate;
[0068] S32, fixing each growing substrate on the face plate 36;
and
[0069] S33, drawing a drawn carbon nanotube film or an untwisted
carbon nanotube wire from each carbon nanotube array using a
stretching tool, and adhering one end of the carbon nanotube film
or untwisted carbon nanotube wire to the linear structure.
[0070] In step S31, the carbon nanotube array is composed of a
plurality of carbon nanotubes. The plurality of carbon nanotubes
can be single-walled carbon nanotubes, double-walled nanotubes,
multi-walled carbon nanotubes, or any combination thereof. In one
embodiment, the plurality of carbon nanotubes comprises
substantially parallel multi-walled carbon nanotubes. The carbon
nanotube array is essentially free of impurities, such as
carbonaceous or residual catalyst particles. The carbon nanotube
array can be a super aligned carbon nanotube array. A method for
making the carbon nanotube array is unrestricted, and can be by
chemical vapor deposition methods or other methods.
[0071] In step S32, each growing substrate with the carbon nanotube
array grown thereon is fixed on the support stage 362 by adhesive,
mechanical tools, or vacuum absorption.
[0072] In step S33, each carbon nanotube film or untwisted carbon
nanotube wire can be formed by selecting one or more carbon
nanotubes having a predetermined width from each carbon nanotube
array, and pulling the carbon nanotubes at a uniform speed to form
carbon nanotube segments that are joined end to end to achieve the
uniform drawn carbon nanotube film or untwisted carbon nanotube
wire. During the pulling process, as the initial carbon nanotube
segments are drawn out, other carbon nanotube segments are also
drawn out end to end due to van der Waals force between ends of
adjacent segments. The stretching tool can be a ruler, tweezers, or
an adhesive tape.
[0073] It is noted that because the carbon nanotubes in the carbon
nanotube array have a high purity and a high specific surface area,
the drawn carbon nanotube film or untwisted carbon nanotube wire is
adhesive. As such, the carbon nanotube film or untwisted carbon
nanotube wire can be adhered to the surface of the linear structure
directly and a plurality of drawn carbon nanotube films or
untwisted carbon nanotube wires can be adhered to a surface one
after another.
[0074] The step S40 can include the steps of operating the first
motor 322 to rotate the face plate 38 and controlling the
collecting unit 40 to move the linear structure along the fixed
direction, such that the carbon nanotube structure is wound around
the linear structure. Specifically, when the collecting unit 40 and
wrapping unit 30 are operated, the linear structure can be
continuously supplied by the supply unit 20 and move towards the
collecting unit 40. The drawn carbon nanotube film or untwisted
carbon nanotube wire can be continuously drawn from each carbon
nanotube array. Simultaneously, the first motor 322 drives the
hollow rotating shaft 34 to rotate around the first axis 344 of the
hollow rotating shaft 34 along a first direction. If the hollow
rotating shaft 34 rotates, the face plate 38 and the at least one
carbon nanotube array located on the face plate 38 can be rotated
around the first axis 344 of the hollow rotating shaft 34 along the
first direction. The drawn carbon nanotube film or untwisted carbon
nanotube wire stretched from each carbon nanotube array can be
wrapped around the surface of the linear structure along the first
direction. Therefore, the carbon nanotube composite wire is formed.
If the second motor 42 drives the collecting shaft 44 to rotate,
the carbon nanotube composite wire can be automatically wound
around the collecting shaft 44. Thus, the carbon nanotube composite
wire can be continuously manufactured and collected on the
collecting shaft 44. Therefore, the rotating speeds of the
collecting shaft 44 and the face plate 38 cooperatively affect the
thickness of the carbon nanotube layer.
[0075] In one embodiment, the step S40 can further include a step
of repeating the above mentioned step S40, wherein the face plate
38 can be driven to rotate along a second direction opposite to the
first direction by the first motor 322. Thus, the drawn carbon
nanotube film or untwisted carbon nanotube wire is wound around the
linear structure along the second direction.
[0076] In one embodiment, the carbon nanotube tube structure 10 can
be made by the following steps:
[0077] S100, providing an aluminum thread with a diameter of about
25 .mu.m by the supply unit 20;
[0078] S200, passing the aluminum thread through the hollow
rotation shaft 34, and fixing the aluminum thread on the collecting
unit 40;
[0079] S300, providing six drawn carbon nanotube films by the
wrapping unit 30, and adhering the six drawn carbon nanotube films
to the aluminum thread;
[0080] S400, rotating the face plate 38 and pulling the aluminum
thread along a fixed direction to wind the six drawn carbon
nanotube films around the aluminum thread, thereby forming a carbon
nanotube aluminum composite wire structure with a diameter of about
50 .mu.m; and
[0081] S500, etching the aluminum thread in the carbon nanotube
aluminum composite wire structure with hydrochloric acid with a
concentration of about 0.5 molars per liter (mol/L), to remove the
aluminum thread.
[0082] According to the above description, the carbon nanotube tube
structure is a macro-scale tube-shaped structure and includes a
plurality of carbon nanotubes. Carbon nanotubes are lightweight and
flexible, so the carbon nanotube tube structure will also be
light-weight and flexible. The carbon nanotubes have small thermal
capacity. The carbon nanotube tube structure has a smaller capacity
compared with other thermal conductive materials. The carbon
nanotubes also have high strength. If the carbon nanotube tube
structure is a tube shaped structure, the carbon nanotube tube
structure has a relative high strength compared with other tube
shaped structures. Therefore, the carbon nanotube tube structure
can be conveniently applied in various fields.
[0083] In addition, the macro-scale carbon nanotube tube structure
can be made by winding the carbon nanotube structure around the
linear structure and removing the linear structure, the method is
simple, and easy to quickly produce. The carbon nanotube structure
is a free-standing structure, and includes at least one carbon
nanotube film or at least one carbon nanotube wire. The at least
one carbon nanotube film or at least one carbon nanotube wire also
has an adhesive property. After being wrapped around the linear
structure, the overlapped carbon nanotube films or carbon nanotube
wires can be adhered to each other by van der Waals force. Thus,
the carbon nanotube tube structure can have a stable structure.
[0084] It is to be understood that the above-described embodiment
is intended to illustrate rather than limit the disclosure.
Variations may be made to the embodiment without departing from the
spirit of the disclosure as claimed. The above-described
embodiments are intended to illustrate the scope of the disclosure
and not restricted to the scope of the disclosure.
[0085] It is also to be understood that the above description and
the claims drawn to a method may include some indication in
reference to certain steps. However, the indication used is only to
be viewed for identification purposes and not as a suggestion as to
an order for the steps.
* * * * *