U.S. patent application number 15/951341 was filed with the patent office on 2019-08-01 for oxidation fiber manufacturing method.
The applicant listed for this patent is UHT UNITECH COMPANY LTD.. Invention is credited to CHIH-YUNG WANG.
Application Number | 20190233977 15/951341 |
Document ID | / |
Family ID | 62116203 |
Filed Date | 2019-08-01 |
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United States Patent
Application |
20190233977 |
Kind Code |
A1 |
WANG; CHIH-YUNG |
August 1, 2019 |
OXIDATION FIBER MANUFACTURING METHOD
Abstract
The present disclosure mainly uses a transmitting unit to drive
the fiber yarn bunch to pass an operation region of the microwave
processing unit, and the microwave is focused to perform an
ultra-fast pre-oxidization process on the passed fiber yarn bunch,
thus processing the fiber yarn bunch to form an oxidation fiber
yarn bunch. Not only an oxidization time of an oxidation fiber can
be reduced, but also the cross section area of the oxidation layer
of the oxidation fiber in the oxidation fiber yarn bunch generated
by the microwave focusing oxidization process occupies more than
50% of the cross section area of the oxidation fiber in the
oxidation fiber yarn bunch. Thus, the shell-core structure of the
oxidation fiber can be reduced efficiently. Even, the oxidation
fiber has no obvious shell-core structure. Accordingly, relatively
positive and reliable means for increasing the performance of
carbon fiber are provided.
Inventors: |
WANG; CHIH-YUNG; (TAOYUAN
CITY, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UHT UNITECH COMPANY LTD. |
TAOYUAN CITY |
|
TW |
|
|
Family ID: |
62116203 |
Appl. No.: |
15/951341 |
Filed: |
April 12, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D01F 9/225 20130101;
D01F 9/14 20130101; D01F 11/16 20130101; D01F 9/32 20130101; D10B
2321/10 20130101; D10B 2401/063 20130101; D10B 2211/04 20130101;
D01D 10/0454 20130101; D10B 2101/12 20130101; D01F 9/18
20130101 |
International
Class: |
D01F 11/16 20060101
D01F011/16; D01D 10/04 20060101 D01D010/04; D01F 9/18 20060101
D01F009/18; D01F 9/32 20060101 D01F009/32 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 29, 2018 |
TW |
107103128 |
Claims
1. An oxidation fiber manufacturing method, used to pre-oxidize a
fiber yarn bunch to form an oxidation fiber yarn bunch; the fiber
yarn bunch is formed by merely one fiber, or alternatively, the
fiber yarn bunch is formed by binding a plurality of fibers; the
oxidation fiber yarn bunch is formed by merely one oxidation fiber,
or alternatively, the oxidation fiber yarn bunch is formed by
binding a plurality of oxidation fibers; the oxidation fiber
manufacturing method comprises following steps: a yarn bunch
providing step: preparing the fiber yarn bunch; and a microwave
processing step: exposing the fiber yarn bunch in a microwaving
condition to form the oxidation fiber yarn bunch.
2. The oxidation fiber manufacturing method according to claim 1,
wherein the microwaving condition comprises: a microwave frequency
being 300 MHz through 300,000 MHz; a microwave power being 1
kW/m.sup.2 through 1000 kW/m.sup.2 ; an operation temperature being
100.degree. C. through 600.degree. C.; a processing time being 1
minute through 40 minutes; and a gas atmosphere being at least one
of oxygen, air and ozone.
3. The oxidation fiber manufacturing method according to claim 2,
wherein the microwave power is 10 kW/m.sup.2 through 24 kW/m.sup.2
.
4. The oxidation fiber manufacturing method according to claim 2,
wherein the microwave frequency is 2000 MHz through 3000 MHz, the
operation temperature being 150.degree. C. through 350.degree. C.,
and the processing time is 5 minutes through 20 minutes.
5. The oxidation fiber manufacturing method according to claim 1,
wherein the fiber yarn bunch is one of a polyacrylonitrile (PAN)
fiber and a pitch fiber.
6. An oxidation fiber manufacturing method, used to pre-oxidize a
fiber yarn bunch to form an oxidation fiber yarn bunch; the fiber
yarn bunch is formed by merely one fiber, or alternatively, the
fiber yarn bunch is formed by binding a plurality of fibers; the
oxidation fiber yarn bunch is formed by merely one oxidation fiber,
or alternatively, the oxidation fiber yarn bunch is formed by
binding a plurality of oxidation fibers; the oxidation fiber
manufacturing method comprises following steps: a. providing a
transmitting unit and a microwave processing unit; b. providing the
fiber yarn bunch, disposing the fiber yarn bunch in the
transmitting unit, and making the transmitting unit drive the fiber
yarn bunch to pass the microwave processing unit; c. activating the
microwave processing unit, and generating a microwaving condition
by microwave processing unit; and d. activating the transmitting
unit, and driving the fiber yarn bunch to be processed for a
processing time under the microwaving condition by the transmitting
unit, so as to make the fiber yarn bunch form the oxidation fiber
yarn bunch.
7. The oxidation fiber manufacturing method according to claim 6,
wherein the microwaving condition comprises: a microwave frequency
being 300 MHz through 300,000 MHz; a microwave power being 1
kW/m.sup.2 through 1000 kW/m.sup.2 ; an operation temperature being
100.degree. C. through 600.degree. C.; and a gas atmosphere being
at least one of oxygen, air and ozone
8. The oxidation fiber manufacturing method according to claim 7,
wherein the processing time is 1 minute through 40 minutes.
9. The oxidation fiber manufacturing method according to claim 7,
wherein the microwave power is 10 kW/m.sup.2 through 24 kW/m.sup.2
.
10. The oxidation fiber manufacturing method according to claim 7,
the microwave frequency is 2000 MHz through 3000 MHz, and the
operation temperature being 150.degree. C. through 350.degree.
C.
11. The oxidation fiber manufacturing method according to claim 6,
the fiber yarn bunch is one of a polyacrylonitrile (PAN) fiber and
a pitch fiber.
12. The oxidation fiber manufacturing method according to claim 6,
wherein the transmitting unit is installed with a feeding unit for
providing the fiber yarn bunch, a winder unit for continuously
pulling and transmitting the fiber yarn bunch, and an oven body
which the fiber yam bunch passes; the microwave processing unit is
installed with a magnetron at the oven body for generating the
microwave frequency and the microwave power, and is further
installed with an gas supplying unit for injecting a gas atmosphere
into the oven body.
13. The oxidation fiber manufacturing method according to claim 12,
wherein the winder unit, the magnetron and the gas supplying unit
are electrically connected to a control unit.
14. The oxidation fiber manufacturing method according to claim 12,
wherein interior of the oven body is installed with a thermos
unit.
15. The oxidation fiber manufacturing method according to claim 14,
wherein the thermos unit is at least one of a metal oxide, a
carbide and a high microwave sensitive material.
16. The oxidation fiber manufacturing method according to claim 12,
wherein the fiber yarn bunch disposed is disposed in the oven body
by a repeating and winding manner, and continuously irradiated by
the microwave processing unit.
Description
BACKGROUND
1. Technical Field
[0001] The present disclosure relates to a carbon fiber
pre-oxidization technology, in particular to disclose an oxidation
fiber manufacturing method of helping to enhance the performance of
the carbon fiber.
2. Description of Related Art
[0002] The carbon fiber is a new carbon material with 90% carbon
concentration, in which the organic fiber is performed with
sequential thermal processes to transform to such carbon fiber. The
carbon fiber has advantages of the high specific strength, the high
specific modulus, the high conductivity and the thermal
conductivity, the low thermal expansion coefficient, the low
density, the high temperature resistance, the fatigue resistance,
the creep resistance and the self-lubrication, and is an ideal
function and structure material being widely used in the aerospace,
civil aviation and transportation and other fields, thus having
wide application prospects.
[0003] The carbon fiber preparing process using polyacrylonitrile
(PAN) as the raw silk comprises polymerization, spinning,
pre-oxidization and carbonization processes, wherein the
pre-oxidization process is the key structure transformation stage
of in the carbon fiber preparing process, and is the most time
consuming stage in the thermal processing processes, which has the
objective of transforming the linear macromolecular chains of
polyacrylonitrile to the oxidation fiber with the thermal
resistance structure, such that the oxidation fiber in the next
carbonization will not burned and melted, and can maintain the
fiber shape.
[0004] The structure transformation of the raw silk in the
pre-oxidization process mainly determines the structure and the
performance of the carbon fiber. During the industrial production,
the pre-oxidization process with gradient temperature increasing
manner is mostly used, and the proper gradient temperature range in
the process is required. If the initial temperature is too low, it
will not contribute to the pre-oxidization process, and the
consuming time will be increased to cause the large cost. By
contrast, if the initial temperature is too high, the heat emission
of the severe reaction will make the macromolecular chains of
polyacrylonitrile be melted, wherein the macromolecular chains of
polyacrylonitrile have no thermal resistance. In addition, if the
termination temperature is too high, the concentrated heat emission
destroys the structure of the pre-oxidization silk, and makes the
pre-oxidization silk over oxidized, and thus it is hard to prepare
the carbon fiber with high strength. However, if the termination
temperature is too low, the raw silk is not pre-oxidized
sufficiently.
[0005] Moreover, when the pre-oxidization process is performed by
heating, accompanying with the progressing of the pre-oxidization,
since the heat is transmitted from the outer layer of the raw silk
to the inner layer of the raw silk, the outer layer of the raw silk
is firstly formed with an oxidization layer (i.e. the shell
portion) having compact trapezoidal structure, and this prevents
the oxygen from diffusing to the core portion of the raw silk. As
such, as shown in FIG. 1, this causes an obviously differential
shell-core structure between the oxidation layer 111 (shell
portion) generated by oxidizing one fiber 11 in the oxidation fiber
10 and the core portion 112 being not oxidized, and a shell-core
interface 113 exists between the oxidation layer 111 and the core
portion 112. To check the shell-core structure, the scanning
electron microscope (SEM) can photograph the substantial image to
observe the cross section of the oxidation fiber and to
respectively calculate the cross section areas of the oxidation
layer, the core portion and the oxidation fiber. The core portion
degree (%) can be used to evaluate the degree of the shell-core
structure, wherein the core portion degree is the value that the
cross section area of the core portion divides the summation of the
cross section areas of the oxidation layer and the core portion,
i.e. the value that the cross section area of the core portion
divides the cross section area of the oxidation fiber. In addition,
the physical properties of the oxidation fiber 10 and its
manufactured carbon fiber, such as the tensile strength and the
tensile modulus, are further determined by the oxidization degree
and the cyclization degree of the oxidation fiber 10 or the
oxidation layer 111. That is, the higher the oxidization degree and
the cyclization degree of the oxidation fiber 10 or the oxidation
layer 111 are, the higher the tensile strength and the tensile
modulus of the carbon fiber manufactured by the oxidation fiber 10
are. The oxidation layer 111 presents the oxidation status and the
structure thereof is compact, such that the manufactured carbon
fiber thereof has the high tensile strength and the high tensile
modulus. The core portion 112 presents the non-complete oxidation
status or the non-oxidation status, and the structure thereof is
loose, such that the manufactured carbon fiber thereof has the low
tensile strength and the low tensile modulus. Since the oxidation
layer 111 and the core portion 112 have the different oxidization
degrees, the resulted shell-core structure is one important factor
of lowering the tensile strength of the carbon fiber. Thus, how to
shorten the pre-oxidization time in the pre-oxidization reaction
process and how to simultaneously increase the pre-oxidization
degree and eliminate the shell-core structure have importance of
decreasing the carbon fiber manufacturing cost and increasing the
performance (such as the tensile strength and the tensile
modulus).
SUMMARY
[0006] Accordingly, the present disclosure provides an oxidation
fiber manufacturing method which has the main objectives of
shortening the oxidization time of the oxidation fiber, efficiently
eliminating the shell-core structure of the oxidation fiber, and
even making the oxidation fiber have no obvious shell-core
structure.
[0007] The present disclosure provides an oxidation fiber
manufacturing method used to pre-oxidize a fiber yarn bunch to form
an oxidation fiber yarn bunch. The fiber yarn bunch is formed by
merely one fiber, or alternatively, the fiber yarn bunch is formed
by binding a plurality of fibers. The oxidation fiber yam bunch is
formed by merely one oxidation fiber, or alternatively, the
oxidation fiber yarn bunch is formed by binding a plurality of
oxidation fibers. The oxidation fiber manufacturing method
comprises following steps: [0008] a yarn bunch providing step:
preparing the fiber yarn bunch; and [0009] a microwave processing
step: exposing the fiber yarn bunch in a microwaving condition to
form the oxidation fiber yarn bunch.
[0010] In one embodiment, an oxidation fiber manufacturing method
of the present disclosure is used to pre-oxidize a fiber yarn bunch
to form an oxidation fiber yarn bunch. The fiber yarn bunch is
formed by merely one fiber, or alternatively, the fiber yarn bunch
is formed by binding a plurality of fibers. The oxidation fiber
yarn bunch is formed by merely one oxidation fiber, or
alternatively, the oxidation fiber yarn bunch is formed by binding
a plurality of oxidation fibers. the oxidation fiber manufacturing
method comprises following steps: [0011] a. providing a
transmitting unit and a microwave processing unit; [0012] b.
providing the fiber yarn bunch, disposing the fiber yarn bunch in
the transmitting unit, and making the transmitting unit drive the
fiber yarn bunch to pass the microwave processing unit; [0013] c.
activating the microwave processing unit, and generating a
microwaving condition by microwave processing unit; and [0014] d.
activating the transmitting unit, and driving the fiber yam bunch
to be processed for a processing time under the microwaving
condition by the transmitting unit, so as to make the fiber yarn
bunch form the oxidation fiber yarn bunch.
[0015] According to the oxidation fiber manufacturing method, the
fiber of the fiber yarn bunch is pre-oxidized to form the oxidation
fiber by using the oxidation fiber manufacturing method.
[0016] According to the oxidation fiber manufacturing method, the
microwaving condition comprises: a microwave frequency being 300
MHz through 300,000 MHz; a microwave power being 1 kW/m.sup.2
through 1000 kW/m.sup.2 ; an operation temperature being
100.degree. C. through 600.degree. C.; and a gas atmosphere being
at least one of oxygen, air and ozone.
[0017] According to the oxidation fiber manufacturing method, a
processing time is 1 minute through 40 minutes.
[0018] According to the oxidation fiber manufacturing method, the
microwave power is 10 kW/m.sup.2 through 24 kW/m.sup.2 .
[0019] According to the oxidation fiber manufacturing method, the
microwave frequency is 2000 MHz through 3000 MHz, the operation
temperature being 150.degree. C. through 350 and the processing
time is 5 minutes through 20 minutes.
[0020] According to the oxidation fiber manufacturing method, he
fiber yarn bunch is one of a polyacrylonitrile (PAN) fiber, a pitch
fiber and other one organic fiber.
[0021] According to the oxidation fiber manufacturing method, the
transmitting unit is installed with a feeding unit for providing
the fiber yarn bunch, a winder unit for continuously pulling and
transmitting the fiber yarn bunch, and an oven body which the fiber
yarn bunch passes. The microwave processing unit is installed with
a magnetron at the oven body for generating the microwave frequency
and the microwave power, and is further installed with a gas
supplying unit for injecting the gas atmosphere into the oven
body.
[0022] According to the oxidation fiber manufacturing method, the
winder unit, the magnetron and the gas supplying unit are
electrically connected to a control unit.
[0023] According to the oxidation fiber manufacturing method,
interior of the oven body is installed with a thermos unit.
[0024] According to the oxidation fiber manufacturing method, the
thermos unit is at least one of a metal oxide, a carbide and a high
microwave sensitive material.
[0025] According to the oxidation fiber manufacturing method, the
fiber yarn bunch disposed is disposed in the oven body by a
repeating and winding manner, and continuously irradiated by the
microwave processing unit.
[0026] The oxidation fiber manufacturing method of the present
disclosure mainly uses the microwave processing unit to focus the
microwave to apply an ultra-fast pre-oxidization process on the
fiber yarn bunch, such that the fiber yarn bunch is processed to
form the oxidation fiber. Not only the oxidization time of the
oxidation fiber can be shortened, but also the cross section area
of the oxidation layer in the oxidation fiber occupies more than
50% of the cross section area of the oxidation fiber, which
efficiently eliminate the shell-core structure. When the cross
section area of the oxidation layer in the oxidation fiber occupies
more than 80% of the cross section area of the oxidation fiber,
even the oxidation fiber has no obvious shell-core structure.
Accordingly, relatively positive and reliable means are provided to
improve the performance of the carbon fiber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings are included to provide a further
understanding of the present disclosure, and are incorporated in
and constitute a part of this specification. The drawings
illustrate exemplary embodiments of the present disclosure and,
together with the description, serve to explain the principles of
the present disclosure.
[0028] FIG. 1 is a schematic diagram showing a shell-core structure
of the conventional oxidation fiber.
[0029] FIG. 2 is basic flow chart showing an oxidation fiber
manufacturing method of the present disclosure.
[0030] FIG. 3 is a schematic diagram showing structures of a
transmitting unit and a microwave processing unit associated with
the oxidation fiber manufacturing method of the present
disclosure.
[0031] FIG. 4 is an oxidization degree curve diagram of oxidation
fibers associated with fiber yarn bunches on which the 12
kW/m.sup.2, 16 kW/m.sup.2, 20 kW/m.sup.2 , and 24 kW/m.sup.2
microwave focusing processes of and the conventional heating
process are respectively performed.
[0032] FIG. 5 is a cyclization degree curve diagram of oxidation
fibers associated with fiber yarn bunches on which the 24
kW/m.sup.2 microwave focusing processes are respectively performed
for 2 minutes, 4 minutes, 5 minutes, 10 minutes and 15 minutes.
[0033] FIG. 6 is a substantial cross section image of the oxidation
fiber of the fiber yarn bunch on which the 24 kW/m.sup.2 microwave
focusing process is performed for 5 minutes.
[0034] FIG. 7 is a substantial cross section image of the oxidation
fiber of the fiber yarn bunch on which the 24 kW/m.sup.2 microwave
focusing process is performed for 10 minutes.
[0035] FIG. 8 is a substantial cross section image of the oxidation
fiber of the fiber yarn bunch on which the 24 kW/m.sup.2 microwave
focusing process is performed for 15 minutes.
[0036] FIG. 9 is a flow chart of another one oxidation fiber
manufacturing method of the present disclosure.
[0037] FIG. 10 is a schematic diagram showing a structure of an
oven body associated with the oxidation fiber manufacturing method
of the present disclosure.
[0038] FIG. 11 is a schematic diagram showing a structure of an
oxidation fiber of the present disclosure.
DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0039] The present disclosure mainly provides an oxidation fiber
manufacturing method which can shorten the oxidization time of the
oxidation fiber, efficiently eliminate the shell-core structure of
the oxidation fiber, and even make the oxidation fiber have no
obvious shell-core structure. As shown in FIG. 2 and FIG. 3, the
oxidation fiber manufacturing method basically comprises the
following steps.
[0040] Step A: providing a transmitting unit 30 and a microwave
processing unit 40. When the present disclosure is implemented, the
transmitting unit 30 is installed with a feeding unit 31 for
providing the fiber yarn bunch 20, a winder unit 32 for
continuously pulling and transmitting the fiber yarn bunch 20, and
an oven body 33 which the fiber yarn bunch 20 passes, wherein the
fiber yarn bunch 20 is formed by merely one fiber (not shown in the
drawings), or alternatively, the fiber yarn bunch 20 is formed by
binding a plurality of fibers. The microwave processing unit 40 is
installed with a magnetron 41 at the oven body 33 for generating
the microwave, and is further installed with an gas supplying unit
42 for injecting a gas atmosphere into the oven body 33. The gas
supplying unit 42 is coupled to a gas inlet 331 of the oven body
33, and the gas with the oxygen is injected into the oven body 33
via the gas inlet 331, and exhausted from the oven body 33 via a
gas outlet 332 of the oven body 33. The transmitting unit 30 is
further installed with a thermos unit 34 in the interior of the
oven body 33. Preferably, the microwave processing unit 40 is
installed with the plurality of the magnetrons 41 at the oven body
33. The magnetrons 41 are disposed at the top and bottom sides of
the oven body 33, and the magnetrons 41 disposed on the top and
bottom sides of the oven body 33 are arranged corresponding to each
other or in an offset manner, or alternatively, the magnetrons 41
are disposed at single one side of the oven body 33 (such as the
top or bottom side). As shown in FIG. 3, the magnetrons 41 are
disposed at the top and bottom sides of the oven body 33, and the
magnetrons 41 disposed on the top and bottom sides of the oven body
33 are arranged corresponding to each other. Optimally, the
magnetrons 41 disposed on the top and bottom sides of the oven body
33 are arranged corresponding to each other as shown in FIG. 3, and
thus by simultaneously and uniformly irradiating the microwave on
the upper and lower portions of the fiber yarn bunch 20 which
passes the oven body 33, the length of the oven body 33 can be
correspondingly reduced, and the process time can be shortened to
increase the production speed.
[0041] Step B: providing the fiber yarn bunch 20, disposing the
fiber yarn bunch 20 in the transmitting unit 30, and making the
transmitting unit 30 drive the fiber yarn bunch 20 to pass the
microwave processing unit 40. For example, the winded fiber yarn
bunch 20 can be disposed at the transmitting unit 30 by the manner
that the winded fiber yarn bunch 20 can be continuously driven by
the transmitting unit 30 to pass the operation region of the
microwave processing unit 40. In the embodiment, the winded fiber
yarn bunch 20 is disposed at the feeding unit 31, and the tail end
of the fiber yarn bunch 20 is guided to pass the oven body 33 and
then fixed on the winder unit 32, wherein the fiber yarn bunch 20
can be one of a polyacrylonitrile (PAN) fiber, a pitch fiber and
other one organic fiber.
[0042] Step C: activating the microwave processing unit 40, and
using the microwave processing unit 40 to generate a microwaving
condition. The microwaving condition comprises: a microwave
frequency being 300 MHz through 300,000 MHz; a microwave power
being 1 kW/m.sup.2 through 1000 kW/m.sup.2 ; an operation
temperature being 100.degree. C. through 600.degree. C.; and a gas
atmosphere being at least one of oxygen, air and ozone. The gas
atmosphere is the above gas with oxygen. In the embodiment, the gas
supplying unit 42 is used to inject the gas with oxygen into the
interior of the oven body 33.
[0043] Step D: activating the transmitting unit 30, using the
transmitting unit 30 to drive the fiber yarn bunch 20 to be exposed
in the microwaving condition for a processing time, so as to
transform the fiber yarn bunch 20 to the oxidation fiber yarn bunch
20A. For example, the fiber yarn bunch 20 is driven by the
transmitting unit 30 to pass the operation region of the microwave
processing unit 40 at the speed which the microwave focusing
process is continuously applied for 1 minute through 40 minutes,
and that is, the processing time is 1 minute through 40 minutes. In
the embodiment, the fiber yarn bunch 20 is driven by the
transmitting unit 30 to pass the oven body 33 to form the oxidation
fiber yarn bunch 20A at the speed which the microwave focusing
process is continuously applied for 1 minute through 40 minutes. In
addition, the fiber yarn bunch 20 in the oven body 33 is winded and
repeated to pass the oven body 33 to the oxidation fiber yarn bunch
20A at the speed which the microwave focusing process is
continuously applied for 1 minute through 40 minutes, so as to form
the oxidation fiber yarn bunch 20A. For example, the fiber yarn
bunch 20 at the front end of the oven body 33 enters the interior
of the oven body 33, and then is transmitted to the back end of the
oven body 33. Next, the fiber yam bunch 20 is transmitted from the
back end of the oven body 33 to the front end of the oven body 33,
and then is transmitted from the front end of the oven body 33 to
the back end of the oven body 33 again. The manner is used to
repeat and wind the fiber yarn bunch 20 until the requirements is
satisfied, and then the fiber yarn bunch 20 is sent out from the
back end of the oven body 33 to form the oxidation fiber yarn bunch
20A. The above used repeating and winding manner can sufficiently
reduce the required length of the oven body 33.
[0044] Accordingly, by using oxidation fiber manufacturing method,
under the operation of the transmitting unit 30, the fiber yarn
bunch 20 is driven to pass the operation region of the microwave
processing unit 40 at the predetermined speed. During the progress
which the fiber yarn bunch 20 passes the operation region of the
microwave processing unit 40, the microwave focusing is
continuously used to apply the ultra-fast pre-oxidization process
on the fiber yarn bunch 20, so as to process the fiber yarn bunch
20 to form the oxidation fiber yam bunch 20A. As shown in FIG. 4,
the fiber yarn bunch 20 is formed by merely one fiber, or
alternatively, the fiber yarn bunch 20 is formed by binding a
plurality of fibers; and the oxidation fiber yarn bunch 20A is
formed by merely one oxidation fiber, or alternatively, the
oxidation fiber yarn bunch 20A is formed by binding a plurality of
oxidation fibers. The oxidation fiber manufacturing method of the
present disclosure can be used to pre-oxidize the fiber of the
fiber yarn bunch 20 to form the oxidation fiber 21.
[0045] Referring to FIG. 4, the fiber yarn bunches 20 are
respectively applied with the non-microwave process and the
microwave focusing processes of 12 kW/m.sup.2, 16 kW/m.sup.2, 20
kW/m.sup.2 and 24 kW/m.sup.2 microwave powers, and it can obtain
the result that the microwave focusing process of 24 kW/m.sup.2 is
applied to the fiber yarn bunch 20 for 10 minutes to make the
oxidization degree of the oxidation fiber 21 in the oxidation fiber
yarn bunch 20A reach 100%. Corresponding to the fiber yarn bunch
20, the oxidation fiber yarn bunch 20A is formed by merely one
oxidation fiber, or alternatively, the oxidation fiber yarn bunch
20A is formed by binding a plurality of oxidation fibers.
Similarly, the microwave focusing process of 20 kW/m.sup.2 is
applied to the fiber yam bunch 20 for 15 minutes to make the
oxidization degree of the oxidation fiber 21 in the oxidation fiber
yarn bunch 20A reach 100%. The microwave focusing process of 16
kW/m.sup.2 is applied to the fiber yarn bunch 20 for 25 minutes to
make the oxidization degree of the oxidation fiber 21 in the
oxidation fiber yarn bunch 20A reach 100%. However, even the
microwave focusing process of 12 kW/m.sup.2 is applied to the fiber
yarn bunch 20 for 40 minutes, the oxidization degree of the
oxidation fiber 21 in the oxidation fiber yarn bunch 20A still
cannot reach 100%, but can reach 89%. If the conventional heating
process at 270.degree. C. ut the microwave is applied to heat the
fiber yarn bunch 20 for 40 minutes, the oxidization degree of the
oxidation fiber 21 can merely reaches 70%. Thus, compared the
microwaving process provided by the present disclosure to the
conventional heating process, the present disclosure can
efficiently increase the oxidization degree of the oxidation fiber
21 and shorten the process time. Especially, when the microwave
focusing process of 24 kW/m.sup.2 is applied to the fiber yarn
bunch 20 for 10 minutes, the oxidization degree of the oxidation
fiber 21 in the oxidation fiber yam bunch 20A can reach 100%, and
thus the 24 kW/m.sup.2 and 40 minutes are the best process
condition of the oxidization stage.
[0046] Referring to FIG. 5, the microwave focusing processes of 24
kW/m.sup.2 are performed on the fiber yarn bunch 20 respectively
for 2 minutes, 4 minutes, 5 minutes, 10 minutes and 15 minutes for
checking the cyclization degrees of the formed oxidation fibers 21.
The cyclization degree of the oxidation fiber 21 reaches 100% after
5 minutes are elapsed. Thus, the required time of 5 minutes that
the cyclization degree reaches 100% is less than the required time
of 10 minutes that the oxidization degree reaches 100%. Referring
to FIG. 6, FIG. 7 and FIG. 8 simultaneously, the cross sections of
oxidation fibers 21 associated with the oxidation fiber yarn
bunches 20A formed by being processed with the microwave focusing
processes of 24 kW/m.sup.2 respectively for 5 minutes, 10 minutes
and 15 minutes are photographed by the scanning electron microscope
to obtain the substantial cross section images. It is found that
the oxidation layer 211 occupies more than 99.0% of the oxidation
fiber 21, or the cross section area of the oxidation layer 211
occupies more than 99.0% of the cross section area of the oxidation
fiber 21, and no obvious shell-core structure exists.
[0047] Refer to Table 1 and Table 2 simultaneously. Table 1 is a
comparison table showing the measured tensile strengths of the
fiber yam bunches 20, the oxidation fiber yarn bunches 20A and the
carbon fiber yarn bunches formed by the next carbonization, wherein
two sets of the fiber yarn bunches 20, the oxidation fiber yarn
bunches 20A and the carbon fiber yarn bunches are respectively
processed by the conventional electro thermal tube heating process
and the microwaving process of the oxidation fiber manufacturing
method of the present disclosure. Table 2 is a comparison table
showing the measured tensile moduli of the fiber yam bunches 20,
the oxidation fiber yarn bunches 20A and the carbon fiber yarn
bunches formed by the next carbonization, wherein two sets of the
fiber yarn bunches 20, the oxidation fiber yarn bunches 20A and the
carbon fiber yarn bunches are respectively processed by the
conventional electro thermal tube heating process and the
microwaving process of the oxidation fiber manufacturing method of
the present disclosure. Regarding the conventional electro thermal
tube heating process, the processing condition is the oven body
temperature of 270.degree. C. and the p g time of 40 minutes,and
the obtained results of the physical properties are called
"comparative example 1". Regarding the microwaving process of the
oxidation fiber manufacturing method of the present disclosure, the
processing condition is the oven body temperature of 220.degree.
C., the microwave frequency of 2450 MHz, the microwave power of 24
kW/m.sup.2 and the processing time of 10 minutes, and the obtained
results of the physical properties are called "embodiment 1". In
both of the comparative example 1 and the embodiment 1, the fiber
yarn bunches 20 are made of polyacrylonitrile.
TABLE-US-00001 TABLE 1 the tensile strength the fiber the oxidation
fiber the carbon fiber (MPa) yarn bunch yarn bunch yarn bunch
comparative 865 221 2824 example 1 embodiment 1 865 164 3675
[0048] In Table 1, the embodiment 1 shows the tensile strength of
the final carbon fiber yarn bunch carbonized by the oxidation fiber
yarn bunch processed with the microwaving process of the oxidation
fiber manufacturing method of the present disclosure is 1.3 times
of that in the comparative example 1 (i.e. 3675 divides 2824), and
that is the tensile strength has the improvement of 30%. The
microwaving process can oxidize polyacrylonitrile more complete,
and the tensile strength of the oxidation fiber yarn bunch
associated with the microwaving process is slightly less than that
of the oxidation fiber yarn bunch associated with the conventional
electro thermal tube heating process, which is another one evidence
that the microwaving process of the oxidation fiber manufacturing
method of the present disclosure can further increase the
oxidization degree of the fiber yam bunch.
TABLE-US-00002 TABLE 2 the tensile modulus the fiber the oxidation
fiber the carbon fiber (GPa) yarn bunch yarn bunch yarn bunch
comparative 8.82 6.03 194.4 example 1 embodiment 1 8.82 6.92
227.1
[0049] In Table 2, embodiment 1 shows the tensile modulus of the
final carbon fiber yarn bunch carbonized by the oxidation fiber
yarn bunch processed with the microwaving process of the oxidation
fiber manufacturing method of the present disclosure is 1.17 times
of that in the comparative example 1 (i.e. 227.1 divides 194.4),
and that is the tensile modulus has the improvement of 17%.
[0050] Accordingly, compared with the oxidation fiber yarn bunches
respectively generated by the fiber yarn bunches on which the
conventional heating process and the microwaving process of the
present disclosure are performed, the microwaving process of the
present disclosure can reduce the required time of the conventional
heating process from 40 minutes to 10 minutes, thus the process
efficiency is increased with three times, and the process time is
reduced. Compared to the conventional heating process, the present
disclosure can enhance the 30% tensile strength and the 17% tensile
modulus of carbon fiber yarn bunch. Compared to the conventional
heating process, the present disclosure can further make the cross
section area of the oxidation layer 2111 of the oxidation fiber 21
in the oxidation fiber yarn bunch 20A occupy more than 99.0% of the
cross section area of the oxidation fiber 21, such that no obvious
shell-core structure exists. The cross section of the oxidation
fiber yarn bunch 20A is more uniform, and thus the tensile strength
and the tensile modulus of the carbon fiber yarn bunch are
increased. The relatively positive and reliable means for enhancing
the carbon fiber performance are therefore provided.
[0051] When the oxidation fiber manufacturing method of the present
disclosure is implemented, the 24 kW/m.sup.2 microwave focusing
process is applied to process the fiber yarn bunch for 5 minutes
through 10 minutes, preferably. Certainly, when the oxidation fiber
manufacturing method of the present disclosure is implemented, the
24 kW/m.sup.2 microwave focusing process is applied to process the
fiber yarn bunch for 5 minutes through 10 minutes. As shown in FIG.
3, the transmitting unit 30 is installed with the feeding unit 31,
the winder unit 32 and the oven body 33, wherein the feeding unit
31 is used to provides the fiber yarn bunch 2, the fiber yarn bunch
20 can pass the oven body 33, and the winder unit 32 is used to
drag the fiber yarn bunch 20 for continuous transmission and to
receive the oxidation fiber yarn bunch 20A. The microwave
processing unit 40 is further installed with the magnetron 41 and
the gas supplying unit 42, wherein the magnetron 41 is disposed at
the oven body 33 for generating the microwave, and the gas
supplying unit 42 is used to inject the gas with oxygen into the
oven body 33. Accordingly, the oxidation fiber manufacturing method
of the present disclosure is adapted to the continuous carbon fiber
yarn bunch generation manner that the fiber yarn bunch 20 passes
the oven body 33 without the reception and winding of the winder
unit 32 and the carbonization is next performed, or alternatively,
the oxidation fiber manufacturing method of the present disclosure
is adapted to the generation manner that the winded fiber yarn
bunch 20 is winded out by the feeding unit 31 and received and
winded by the winder unit 32.
[0052] Certainly, the oxidation fiber manufacturing method of the
present disclosure can also be adapted to the batch generation
manner. The embodiment of the batch generation manner can
sequentially execute the following steps, as shown in FIG. 9. The
oxidation fiber manufacturing method of the present disclosure can
be adapted to pre-oxidize the fiber yarn bunch 20 to form the
oxidation fiber yarn bunch 20A. The steps of FIG. 9 are illustrated
as follows.
[0053] A yarn bunch providing step S01: preparing the fiber yarn
bunch 20. The fiber yarn bunch 20 is formed by merely one fiber, or
alternatively, the fiber yarn bunch 20 is formed by binding a
plurality of fibers. The fiber yarn bunch 20 is one of a
polyacrylonitrile (PAN) fiber, a pitch fiber and other one organic
fiber.
[0054] A microwave processing step S02: exposing the fiber yam
bunch 20 in the microwaving condition to form the oxidation fiber
yarn bunch 20A. The microwaving condition comprises: the microwave
frequency being 300 MHz through 300,000 MHz; the microwave power
being 1 kW/m.sup.2 through 1000 kW/m.sup.2 ; the operation
temperature being 100.degree. C. through 600.degree. C.; the
processing time being 1 minute through 40 minutes; and the gas
atmosphere being at least one of oxygen, air and ozone.
[0055] Furthermore, the oxidation fiber manufacturing method of the
present disclosure is implemented in the embodiment which the
microwave processing unit 40 is installed with the gas supplying
unit 42 for injecting the gas atmosphere into the oven body 33,
wherein the gas atmosphere injected into the oven body 33 by the
gas supplying unit 42 is at least one of oxygen, air and ozone.
[0056] Moreover, the oxidation fiber manufacturing method is
implemented in the embodiment that the transmitting unit 30 is
installed with the feeding unit 31, the winder unit 32 and the oven
body 33, and the microwave processing unit 40 is installed with the
magnetron 41 and the gas supplying unit 42, wherein the feeding
unit 31 is used to provides the fiber yarn bunch 2, the fiber yarn
bunch 20 can pass the oven body 33, the winder unit 32 is used to
drag the fiber yarn bunch 20 for continuous transmission, the
magnetron 41 is disposed at the oven body 33 for generating the
microwave, the gas supplying unit 42 is used to inject the gas with
oxygen into the oven body 33, and the winder unit 32, the magnetron
41 and the gas supplying unit 42 are electrically connected to a
control unit 50. Operations of the winder unit 32, the magnetron 41
and the gas supplying unit 42 are controlled by the control unit
50, and parameters related to the spinning speed of the winder unit
32, the power of the magnetron 41 and flux of the gas supplying
unit 42 are determined according to the property of the processed
fiber yarn bunch 20 or the product specification.
[0057] the oxidation fiber manufacturing method is implemented in
the embodiment that the transmitting unit 30 is installed with the
feeding unit 31, the winder unit 32 and the oven body 33, wherein
the feeding unit 31 is used to provides the fiber yarn bunch 2, the
fiber yarn bunch 20 can pass the oven body 33, the winder unit 32
is used to drag the fiber yarn bunch 20 for continuous
transmission, and the transmitting unit 30 is further installed
with the thermos unit 34 in the interior of the oven body 33, and
as shown in FIG. 10. The thermal storage effect of the thermos unit
34 can be utilized, such that the interior of the oven body 33 can
be keep at the predetermined operation temperature to achieve the
objective of power saving. In FIG. 10, the feeding unit 31 provides
the parallel arranged fiber yarn bunches 20 into the oven body
33.
[0058] When the oxidation fiber manufacturing method of the present
disclosure is implemented, the transmitting unit 30 as shown in
FIG. 3, the thermos units 34 are respectively disposed at top and
bottom sides of the interior of the oven body 33 in respective to a
transmission path of the fiber yam bunch 20; or alternatively, as
shown in FIG. 10, the thermos unit 34 is disposed in the interior
of the oven body 33 for covering the transmission path of the fiber
yarn bunch 20, such that the fiber yarn bunch 20 is heated
uniformly.
[0059] According to the above possible embodiments associated with
the oxidation fiber manufacturing of the present disclosure, the
thermos unit 34 can be selected from at least one of a metal oxide,
a carbide and a high microwave sensitive material.
[0060] When the oxidation fiber manufacturing of the present
disclosure is implemented, as shown in FIG. 3, the magnetrons 41
are respectively disposed at top and bottom sides of the
transmission path of the fiber yarn bunch 20; or alternatively, the
magnetrons 41 are disposed for covering the transmission path of
the fiber yarn bunch 20, such that the microwave focusing process
is uniformly performed on the fiber yarn bunch 20.
[0061] Referring to FIG. 4 again, after the microwave focusing
process of the 12 kW/m.sup.2 microwave power at 220.degree. C. is
applied to the fiber yarn bunch 20 for 40 minutes, the oxidation
degree of the oxidation fiber 21 reaches 89%. However, after the
conventional heating process at 270.degree. C. is applied to the
fiber yarn bunch 20 for 40 minutes without the microwaving process,
the oxidation degree of the oxidation fiber 21 merely reaches 70%.
Therefore, compared to the conventional heating process, the
oxidation fiber manufacturing of the present disclosure can obtain
the higher oxidation degree at the lower temperature, thus
preventing the thermal waste.
[0062] Refer to Table 3, and Table 3 is a comparison table showing
the measured tensile strengths of the fiber yarn bunches 20, the
oxidation fiber yarn bunches 20A and the carbon fiber yarn bunches
formed by the next carbonization, wherein several sets of the fiber
yarn bunches 20, the oxidation fiber yarn bunches 20A and the
carbon fiber yarn bunches are respectively processed by the
conventional electro thermal tube heating process and the
microwaving processes of the oxidation fiber manufacturing method
of the present disclosure. Regarding the conventional electro
thermal tube heating process, the processing condition is the oven
body temperature of 270.degree. C. and the processing time of 40
minutes, and the obtained results of the physical roperties are
called "comparative example 1". Regarding the microwaving processes
of the present disclosure, the processing conditions are the oven
body temperature of 220.degree. C., the microwave frequency of 2450
MHz and the processing time of 10 minutes, and the obtained results
of the physical properties associated with 24 kW/m.sup.2, 22
kW/m.sup.2, 16 kW/m.sup.2 and 15 kW/m.sup.2 microwave powers are
called "embodiment 1", "embodiment 2", "embodiment 3", "embodiment
4" and "embodiment 5". In all of comparative example 1 and
embodiments 1 through 5, the fiber yarn bunches 20 are made of
polyacrylonitrile. In addition, the cross sections of the oxidation
fibers 21 of the oxidation fiber yarn bunches 20A associated with
all of the comparative example 1 and the embodiments 1 through 5
are photographed by the scanning electron microscope to obtain the
substantial cross section images, and the calculated values that
the cross section areas of the oxidation layers 211 respectively
divide the cross section areas of the oxidation fibers 21, i.e. the
ratios which the oxidation layers 211 occupy the oxidation fibers
21, are also listed in Table 3.
TABLE-US-00003 TABLE 3 the tensile strength of the the the fiber
microwave tensile yarn bunch power X* strength number (MPa)
(kW/m.sup.2) (MPa) ratio R* comparative 865 0 2824 1 .sup. 40%
example 1 embodiment 1 865 24 3675 1.30 99.0% embodiment 2 865 22
3580 1.27 91.3% embodiment 3 865 20 3486 1.23 82.7% embodiment 4
865 16 3298 1.17 61.5% embodiment 5 865 15 3204 1.13 51.2% X*: the
tensile strength of the carbon fiber yarn bunch R*: the value that
the cross section area of the oxidation layer divides cross section
area of the oxidation fiber
[0063] In Table 3, embodiment 5 shows the tensile strength of the
final carbon fiber yarn bunch carbonized by the oxidation fiber
yarn bunch processed with the microwaving process of the present
disclosure is 1.13 times of that in the comparative example 1, and
that is the tensile strength has the improvement of 13%. In
embodiment 5, the value that the cross section area of the
oxidation layer 211 divides the cross section area of the oxidation
fiber 21 is 51.2%, i.e. the oxidation layer 211 occupies the 51.2%
oxidation fiber 21. Embodiment 4 shows the tensile strength of the
final carbon fiber yam bunch carbonized by the oxidation fiber yarn
bunch processed with the microwaving process of the present
disclosure is 1.17 times of that in the comparative example 1, and
that is the tensile strength has the improvement of 17%. In
embodiment 4, the value that the cross section area of the
oxidation layer 211 divides the cross section area of the oxidation
fiber 21 is 61.5%, i.e. the oxidation layer 211 occupies the 61.5%
oxidation fiber 21. Embodiment 3 shows the tensile strength of the
final carbon fiber yarn bunch carbonized by the oxidation fiber
yarn bunch processed with the microwaving process of the present
disclosure is 1.23 times of that in the comparative example 1, and
that is the tensile strength has the improvement of 23%. In
embodiment 3, the value that the cross section area of the
oxidation layer 211 divides the cross section area of the oxidation
fiber 21 is 82.7%, i.e. the oxidation layer 211 occupies the 82.7%
oxidation fiber 21. Embodiment 2 shows the tensile strength of the
final carbon fiber yarn bunch carbonized by the oxidation fiber
yarn bunch processed with the microwaving process of the present
disclosure is 1.27 times of that in the comparative example 1, and
that is the tensile strength has the improvement of 27%. In
embodiment 2, the value that the cross section area of the
oxidation layer 211 divides the cross section area of the oxidation
fiber 21 is 91.3%, i.e. the oxidation layer 211 occupies the 91.3%
oxidation fiber 21. Embodiment 1 shows the tensile strength of the
final carbon fiber yam bunch carbonized by the oxidation fiber yarn
bunch processed with the microwaving process of the present
disclosure is 1.3 times of that in the comparative example 1, and
that is the tensile strength has the improvement of 30%. In
embodiment 1, the value that the cross section area of the
oxidation layer 211 divides the cross section area of the oxidation
fiber 21 is 99.0%, i.e. the oxidation layer 211 occupies the 99.0%
oxidation fiber 21.
[0064] Thus, the present disclosure further discloses the oxidation
fiber 21, and the oxidation fiber 21 comprises an oxidation layer
211 and a core portion 212, wherein the oxidation layer 211 covers
the outer side of the core portion 212, and the oxidation layer 211
occupy the more than 50% oxidation fiber 21, or the cross section
area of the oxidation layer 211 occupy the more than 50% cross
section area of the oxidation fiber 21. As shown in FIG. 11, the
oxidation layer 211 occupy the more than 80% oxidation fiber 21, or
the cross section area of the oxidation layer 211 occupy the more
than 80% cross section area of the oxidation fiber 21.
[0065] Certainly, the oxidation fiber 21 of the present disclosure
can be formed by using one of the above oxidation fiber
manufacturing methods to process the fiber yarn bunch 20. Since the
oxidation fiber 21 of the present disclosure is formed under the
microwaving condition, the oxidation layer 211 is a microwaved
oxidation layer, and the oxidation layer 211 of the oxidation fiber
21 in the oxidation fiber yarn bunch 20A occupies the at least 50%
oxidation fiber 21.
[0066] When the present disclosure is implemented, the fiber yarn
bunch 20 can be one of polyacrylonitrile, pitch and other organic
fibers. Certainly, after the microwave focusing process of 24
kW/m.sup.2 microwave power is applied on the fiber yarn bunch 20
for 10 minutes to obtain the oxidation fiber, the oxidation layer
211 occupy the 99.0% oxidation fiber 21, or the cross section area
of the oxidation layer 211 occupy the 99.0% cross section area of
the oxidation fiber 21.
[0067] Compared to the prior art, the oxidization fiber
manufacturing method disclosed by the present disclosure mainly
uses the microwave processing unit to focus the microwave to apply
the ultra-fast pre-oxidization process on the fiber yarn bunch, so
as to process the fiber yam bunch to form the oxidation fiber.
Thus, not only the oxidization time of the oxidation fiber is
reduced, but also the oxidation layer in the oxidation fiber
processed by the microwaving and oxidizing process occupies more
than 50% of the cross section area of the oxidation fiber to
efficiently reduce shell-core structure of the oxidation fiber.
Even, no obvious shell-core structure exists in the oxidation
fiber. Accordingly, relatively positive and reliable means for
increasing the performance of carbon fiber are provided.
[0068] The above-mentioned descriptions represent merely the
exemplary embodiment of the present disclosure, without any
intention to limit the scope of the present disclosure thereto.
Various equivalent changes, alternations or modifications based on
the claims of present disclosure are all consequently viewed as
being embraced by the scope of the present disclosure.
* * * * *