TWM564598U - Oxidized fiber structure - Google Patents

Abstract

The present invention relates to an oxidized fiber structure comprising at least one oxidized fiber, the oxidized fiber further comprising an oxide layer and a core, the oxide layer being coated on the outer side of the core. The creation uses the microwave focusing of the microwave processing unit to apply ultra-high-speed pre-oxidation treatment to the passed fiber yarn bundle, and processes the fiber yarn bundle into oxidized fiber, which can effectively reduce the oxidation time of the oxidized fiber, and the fiber among the oxidized fibers passes through the microwave. The oxidation-treated oxide layer accounts for at least 50% of the cross-sectional area of the oxidized fiber, effectively reducing the sheath-core structure of the oxidized fiber, and even allowing the oxidized fiber to have no obvious sheath-core structure, thereby being relatively more active and reliable. Improve carbon fiber performance.

Description

Oxidized fiber structure

This creation is related to the pre-oxidation technology of carbon fiber, mainly revealing an oxidized fiber structure that contributes to the improvement of carbon fiber properties.

Carbon fiber is a new carbon material with a carbon content of more than 90% after a series of heat treatment of organic fibers. It has high specific strength, high specific modulus, high electrical and thermal conductivity, low thermal expansion coefficient, low density, A series of excellent performances such as high temperature resistance, fatigue resistance, creep resistance and self-lubrication are ideal functional materials and structural materials. They are widely used in aerospace, civil aviation and transportation fields, and have broad application prospects.

Polyacrylonitrile (PAN) as a raw material for carbon fiber preparation includes polymerization, spinning, pre-oxidation and carbonization. The pre-oxidation process is a key stage in the structural transformation of carbon fiber preparation process and the most time-consuming process in the heat treatment process. In the stage, the purpose is to convert the linear macromolecular chain of polyacrylonitrile into an oxidized fiber having a heat-resistant structure, so that it does not melt and burn in the subsequent carbonization, and can maintain the fiber morphology.

The structural transformation of the raw silk in the pre-oxidation process largely determines the structure and properties of the carbon fiber. In industrial production, the pre-oxidation method using gradient heating is adopted in many stages, and a suitable temperature gradient range is necessary in this process. If the initial temperature is too low, it does not contribute to the pre-oxidation process, which takes time to increase the cost, but the initial temperature is too high, and the intense reaction exotherm will melt the PAN macromolecular chain without heat resistance; in addition, if the termination temperature is too high, concentrate The exotherm destroys the structure of the pre-oxidized filament and causes excessive pre-oxidation, which is not conducive to the preparation of high-strength carbon fibers, but the termination temperature is too low, and the original filament may not be sufficiently pre-oxidized.

Further, when the pre-oxidation reaction is carried out by heating, as the pre-oxidation reaction proceeds, since the heat is transferred from the outer layer of the raw yarn to the inner layer, an oxide layer having a dense trapezoidal structure is first formed on the outer layer of the original filament ( The skin portion, which in turn hinders the diffusion of oxygen into the core of the inner layer of the original filament, causing one of the oxidized fibers 10, as shown in Fig. 1, to oxidize an oxide layer 111 (skin) and not yet oxidized. A core-sheath structure in which a core portion 112 is significantly different, and a core-core interface 113 exists between the oxide layer 111 and the core portion 112. The inspection of the sheath-core structure is performed by scanning a solid image image using a scanning electron microscope (SEM) to observe the cross section of the oxide layer and calculating the cross-sectional area of the oxide layer and the cross-sectional area of the core. The cross-sectional area of the oxidized fiber, the degree of the core structure is determined by the core ratio (%) equal to the cross-sectional area of the core divided by the sum of the cross-sectional area of the oxide layer and the cross-sectional area of the core That is, the core ratio (%) is equal to the cross-sectional area of the core divided by the cross-sectional area of the oxidized fiber. In addition, the physical properties of the oxidized fiber 10 and the carbon fiber produced therefrom, such as tensile strength and tensile modulus, are also dependent on the degree of oxidation and degree of cyclization of the oxidized fiber 10 or the oxide layer 111; The higher the degree of oxidation and the degree of cyclization of the oxide layer 111, the higher the tensile strength and tensile modulus of the carbon fiber produced by the oxidized fiber 10. The oxide layer 111 is in an oxidized state, so that the structure is dense and results in high tensile strength and high tensile modulus of the produced carbon fiber. The core portion 112 is incompletely oxidized or unoxidized, so that the structure is loose and causes the resulting structure. Since the carbon fiber has low tensile strength and low tensile modulus, the sheath-core structure caused by the oxidation degree of the oxide layer 111 and the core portion 112 is one of the main causes of the decrease in the tensile strength of the carbon fiber. Therefore, how to shorten the pre-oxidation time during the pre-oxidation reaction, and how to increase the degree of pre-oxidation while reducing or even eliminating the sheath-core structure, the reduction of carbon fiber production cost and the improvement of properties (tensile strength and tensile modulus) are very Significance.

In view of this, the present invention provides a oxidized fiber which can effectively shorten the oxidation time of the oxidized fiber and effectively reduce the wicking structure of the oxidized fiber, and even the oxidized fiber structure to have no obvious sheath core structure.

The oxidized fiber structure of the present invention utilizes a method for producing a oxidized fiber, which is suitable for pre-oxidizing a bundle of fiber yarns into a bundle of oxidized fiber fibers, the bundle of fibers being assembled from a fiber or a plurality of fibers. The oxidized fiber yarn bundle is composed of a oxidized fiber or a plurality of oxidized fibers, and the oxidized fiber manufacturing method comprises the following steps: a yarn supplying step: preparing the fiber yarn bundle; and microwave processing Step: The fiber bundle is exposed to a microwave condition and becomes the oxidized fiber bundle.

In an embodiment, the method for producing an oxidized fiber is suitable for pre-oxidizing the fiber bundle into the oxidized fiber bundle, and the fiber bundle is composed of a bundle of the fiber or a plurality of the bundles. The oxidized fiber yarn bundle is composed of a oxidized fiber or a plurality of the oxidized fibers, and the oxidized fiber manufacturing method comprises the following steps: a. providing a conveying unit and a microwave processing unit; b. providing the fiber yarn bundle And locating the fiber bundle to the transfer unit, and enabling the transfer unit to drive the fiber bundle through the microwave processing unit; c. activating the microwave processing unit, the microwave processing unit generating the microwave condition; d. The transfer unit is activated, and the fiber bundle is driven by the transfer unit under the microwave condition for a processing time to make the fiber bundle into the oxidized fiber bundle.

According to the above method for producing an oxidized fiber, the fiber of the fiber bundle is pre-oxidized into the oxidized fiber by the oxidized fiber production method.

According to the above method for manufacturing an oxidized fiber, the microwave condition comprises: a microwave frequency, the microwave frequency is between 300 and 300,000 MHz; and a microwave power, the microwave power is between 1 and 1000 kW/m ² ; The operating temperature is between 100 and 600 ° C; and, in a gas atmosphere, the gas atmosphere is one of oxygen, air, ozone or a mixture thereof.

According to the above method for producing an oxidized fiber, the treatment time is from 1 to 40 minutes.

According to the above method for producing an oxidized fiber, the microwave power is between 10 and 24 kW/m ² .

According to the above method for producing an oxidized fiber, the microwave frequency system is between 2000 and 3000 MHz, the operating temperature is between 150 and 350 ° C, and the processing time is between 5 and 20 minutes.

According to the above method for producing an oxidized fiber, the fiber bundle is one of polyacrylonitrile (PAN) fibers, pitch fibers or other organic fibers.

According to the above method for producing an oxidized fiber, the conveying unit is provided with a feeding unit for supplying the fiber yarn bundle, a winding unit for continuously conveying the fiber yarn bundle, and a furnace body for passing the fiber yarn bundle; the microwave The processing unit is provided with a magnetron for generating the microwave frequency and the microwave power, and a gas supply unit for introducing the gas atmosphere into the furnace body.

According to the above method for manufacturing an oxidized fiber, the winding unit, the magnetron and the gas supply unit are electrically connected to a control unit.

According to the above method for producing an oxidized fiber, a heat insulating unit is provided inside the furnace body.

According to the above method for producing an oxidized fiber, the heat insulating unit is one of a metal oxide, a carbide, a microwave high induction material, or a combination thereof.

According to the above method for producing an oxidized fiber, the fiber bundle is continuously received by the microwave processing unit in a winding manner in the furnace body.

The present invention discloses an oxidized fiber structure comprising at least one oxidized fiber, wherein the oxidized fiber further comprises an oxide layer and a core, the oxide layer is coated on the outer side of the core, the oxide layer The cross-sectional area of the oxidized fiber is at least 50%. Wherein the oxidized fiber is made by exposing the fiber to the microwave condition. Preferably, the oxidized fiber is made by exposing an organic fiber to the microwave condition.

According to the above structural feature, the cross-sectional area of the oxide layer accounts for at least 60% of the cross-sectional area of the oxidized fiber.

According to the above structural feature, the cross-sectional area of the oxide layer accounts for at least 80% of the cross-sectional area of the oxidized fiber.

According to the above structural feature, the cross-sectional area of the oxide layer accounts for at least 90% of the cross-sectional area of the oxidized fiber.

According to the above structural feature, the cross-sectional area of the oxide layer accounts for at least 99% of the cross-sectional area of the oxidized fiber.

The oxidized fiber structure disclosed in the present invention mainly uses the microwave focusing of the microwave processing unit to apply ultra-high-speed pre-oxidation treatment to the fiber bundle, and processes the fiber bundle into oxidized fiber, which can effectively reduce the oxidation time of the oxidized fiber and oxidize. The oxide layer in the fiber accounts for at least 50% of the cross-sectional area of the oxidized fiber, and effectively reduces the sheath-core structure of the oxidized fiber; when the oxide layer in the oxidized fiber accounts for at least 80% of the cross-sectional area of the oxidized fiber, It can even make the oxidized fiber reach a clear core-free structure. Therefore, this creation enhances carbon fiber performance with a relatively more active and reliable means.

The present invention mainly provides an oxidized fiber structure comprising at least one oxidized fiber, which is produced by an oxidized fiber manufacturing method, which can effectively shorten the oxidation time of the oxidized fiber and is effective Reducing the core structure of the oxidized fiber, and even allowing the oxidized fiber structure to have no obvious sheath core structure. As shown in Figures 2 and 3, the method for producing an oxidized fiber basically comprises the following steps:

a transport unit 30 and a microwave processing unit 40 are provided; in practice, the transport unit 30 is provided with a feeding unit 31 for providing a fiber bundle 20, and a winding for continuously transporting the fiber bundle 20 a unit 32, a furnace body 33 through which the fiber bundle 20 passes, wherein the fiber bundle 20 may be composed of a fiber (not shown) or a plurality of fibers bundled; the microwave processing unit 40 is attached to The furnace body 33 is provided with at least one magnetron 41 for generating microwaves, and a gas supply unit 42 for introducing oxygen-containing gas into the furnace body 33. The air supply unit 42 is connected to an air inlet 331 of the furnace body 33. The oxygen-containing system enters the furnace body 33 from the air inlet 331 and is discharged from an air outlet 332 of the furnace body 33. The transfer unit 30 is further provided with a heat retention unit 34 inside the furnace body 33. Preferably, the microwave processing unit 40 is provided with a plurality of the magnetrons 41 at the furnace body 33; a plurality of the magnetrons 41 are disposed on opposite sides of the furnace body 33 in a relative or misaligned manner, or A plurality of the magnetrons 41 are disposed on one side (upper side or lower side) of the furnace body 33. A plurality of the magnetrons 41 are disposed on the upper and lower sides of the furnace body 33 as shown in FIG. Arrangement. Preferably, the plurality of magnetrons 41 as shown in FIG. 3 are arranged in an up-and-down manner so that the upper and lower halves of the fiber bundle 20 passing through the furnace body 33 are simultaneously and uniformly The treatment by microwave irradiation makes it possible to shorten the length of the furnace body 33 and thereby shorten the process time and speed up the production.

b. The fiber bundle 20 is provided and the fiber bundle 20 is placed in the transfer unit 30 and the transfer unit 30 is enabled to pass the fiber bundle 20 through the microwave processing unit 40. For example, the bundle of the fiber bundles 20 to be wound up is mounted to the transfer unit 30 in a form that can be continuously driven by the transfer unit 30 through the working area of the microwave processing unit 40; in an embodiment, the fibers are wound into a roll. The yarn bundle 20 is placed on the feeding unit 31, and the trailing end of the fiber bundle 20 is guided through the furnace body 33 and fixed to the winding unit 32; the fiber yarn bundle 20 may be polyacrylonitrile ( PAN), one of asphalt or other organic fibers.

The microwave processing unit 40 is activated, and the microwave processing unit 40 generates a microwave condition, the microwave condition includes: a microwave frequency, the microwave frequency is between 300 and 300,000 MHz; and a microwave power, the microwave power is between 1~1000 kW/m ² ; at an operating temperature, the operating temperature is between 100 and 600 ° C; and, in a gas atmosphere, the gas atmosphere is one of oxygen, air, ozone or a mixture thereof, and the gas atmosphere is the aforementioned Oxygen-containing gas. In the present embodiment, the oxygen-containing gas is simultaneously introduced into the interior of the furnace body 33 by the gas supply unit 42.

d. The transfer unit 30 is activated, and the fiber bundle 20 is driven by the transfer unit 30 under the microwave condition for a processing time to make the fiber bundle 20 into the oxidized fiber bundle 20A. For example, the fiber bundle 20 is driven by the transport unit 30 to continuously receive the microwave focusing process for 1 to 40 minutes. The working area of the microwave processing unit 40 becomes the oxidized fiber bundle 20A. The processing time is between 1 and 40 minutes. In the present embodiment, the fiber bundle 20 is driven by the transport unit 30 to continue the microwave focusing process of the microwave processing unit 40 for a period of 1 to 40 minutes to pass through the furnace body 33 to become the oxidized fiber yarn bundle 20A. In addition, the fiber bundle 20 can be continuously received in the furnace body 33 in a winding manner to receive the microwave focusing treatment of the microwave processing unit 40 for 1 to 40 minutes, and the oxidized fiber yarn bundle 20A is passed through the furnace body 33. For example, the fiber bundle 20 enters the furnace body 33 at the front end of the furnace body 33 and is conveyed to the rear end of the furnace body 33, and is transferred from the rear end of the furnace body 33 to the front end of the furnace body 33. Then, it is again transferred from the front end of the furnace body 33 to the rear end of the furnace body 33, and the winding is repeated in this manner until it is conveyed from the rear end of the furnace body 33 as needed to become the oxidized fiber yarn bundle 20A. . The use of the winding method can effectively shorten the required length of the furnace body 33.

According to the oxidized fiber manufacturing method, the fiber bundle 20 can be driven by the operation unit 30 to pass through the working area of the microwave processing unit 40 according to a preset speed, and the fiber bundle 20 passes through the microwave processing. During the operation of the unit 40, the fiber bundle 20 continuously passing through the furnace body 33 is subjected to ultra-high speed pre-oxidation treatment by microwave focusing, and the fiber bundle 20 is processed into the oxidized fiber yarn bundle 20A. Referring to FIG. 4 at the same time, the fiber bundle 20 is composed of the fiber or a plurality of fibers bundled, and the oxidized fiber bundle 20A is composed of the oxidized fiber 21 or a plurality of the oxidized fibers 21 The oxidized fiber is produced by pre-oxidizing the fiber of the fiber bundle 20 into the oxidized fiber 21 by the oxidized fiber production method.

Please also refer to Figure 4, the oxidized fiber manufacturing method is implemented without microwave, microwave power 12kW/m ² , microwave power 16 kW/m ² , microwave power 20 kW/m ² , microwave power 24 kW/m. The microwave focusing treatment of ² is performed on the fiber bundle 20, and it can be surely obtained by microwave focusing treatment with a microwave power of 24 kW/m ² after the fiber bundle 20 is passed for 10 minutes, so that the oxidized fiber bundle 20A can be obtained. The oxidation degree of the oxidized fiber 21 is 100%, and the oxidized fiber yarn bundle 20A is composed of a single oxidized fiber 21 or a plurality of the oxidized fibers 21 bundled in bundles. Similarly, after the fiber bundle 20 is subjected to microwave focusing treatment with a microwave power of 20 kW/m ² for 15 minutes, the oxidation degree of the oxidized fiber 21 in the oxidized fiber bundle 20A is 100%; The microwave focusing treatment of the power of 16 kW/m ² is carried out for 25 minutes after the fiber bundle 20 is passed, so that the oxidation degree of the oxidized fiber 21 in the oxidized fiber bundle 20A is 100%. On the other hand, even after only 40 minutes of the fiber bundle 20 having been subjected to microwave focusing treatment with a microwave power of 12 kW/m ² , even if the oxidation degree of the oxidized fiber 21 in the oxidized fiber bundle 20A cannot be 100%, The degree of oxidation of the oxidized fiber 21 can be made 89%. On the other hand, if the fiber bundle 20 is heated at 270 ° C for only 40 minutes in a microwave-free process by a conventional heating process, the oxidation degree of the oxidized fiber 21 is at most 70%. Therefore, the microwave processing process proposed by the oxidized fiber manufacturing method can effectively increase the oxidation degree of the oxidized fiber 21 and shorten the processing time, especially the microwave power of 24 kW/m ² , compared with the conventional heating process. The oxidized fiber 21 treated to the fiber bundle 20 for 10 minutes to achieve a degree of oxidation of 100% is an optimum process condition for performing the oxidation stage.

At the same time, as shown in Fig. 5, the fiber bundle 20 is treated by microwave focusing with a microwave power of 24 kW/m ² , and treated for 2 minutes, 4 minutes, 5 minutes, 10 minutes, and 15 minutes, respectively, and the test is formed. The degree of cyclization of the oxidized fiber 21, that is, the degree of cyclization of the oxidized fiber 21 after 5 minutes reached 100%, so the time required for the degree of cyclization to reach 100% was 5 minutes less than the time required for the degree of oxidation for 10 minutes. Please also refer to FIG. 6 , FIG. 7 and FIG. 8 to separately process the oxidized fiber by microwave focusing treatment of 24 kW/m ² on the fiber bundle 20 for 5 minutes, 10 minutes and 15 minutes, respectively. The cross section of the oxidized fiber 21 in the oxidized fiber yarn bundle 20A manufactured in minutes was taken as a solid image by a scanning electron microscope (SEM), and it was found that the oxide layer 211 accounted for 99.0 of the oxidized fiber 21. The cross-sectional area of % or more of the oxide layer 211 is 99.0% or more of the cross-sectional area of the oxidized fiber 21, and there is no obvious sheath-core structure.

Please also refer to Tables 1 and 2, Table 1 for the conventional process of heating the electric heating tube and the microwave process using the oxidized fiber manufacturing method, and measuring the fiber bundle 20, the oxidized fiber bundle 20A and A comparison table of tensile strengths of carbon fiber yarn bundles produced by subsequent carbonization; Table 2 shows a conventional process for heating an electric heating tube and a microwave process using the method for producing the oxidized fiber, and the fiber bundle 20 and the oxidized fiber yarn bundle are measured. Comparison table of tensile modulus of carbon fiber bundles made of 20A and its subsequent carbonization. In the conventional process of heating the electric heating tube, the process conditions are the temperature of the furnace body of 270 ° C, the treatment time is 40 minutes, and the obtained physical property results are listed as "Comparative Example 1"; the microwave process of the oxidized fiber manufacturing method described above, The process conditions are as follows: the temperature of the furnace body is 220 ° C, the microwave frequency is 2450 MHz, the microwave power is 24 kW/m ² , and the treatment time is 10 minutes. The obtained physical property results are listed as "Example 1". The fiber bundle 20 of Comparative Example 1 and Example 1 was made of polyacrylonitrile.

Table I:  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Tensile strength (MPa) </td><td> Fiber yarn bundle</td>< Td> oxidized fiber yarn bundle </td><td> carbon fiber yarn bundle </td></tr><tr><td> Comparative Example 1 </td><td> 865 </td><td> 221 < /td><td> 2824 </td></tr><tr><td> Example 1 </td><td> 865 </td><td> 164 </td><td> 3675 </ Td></tr></TBODY></TABLE> From Table 1, the oxidized fiber yarn bundle prepared in the microwave process using the oxidized fiber manufacturing method of Example 1 is shown, and the carbon fiber yarn bundle after the final carbonization is pulled. The tensile strength was 1.3 times that of Comparative Example 1 (3675 divided by 2824), that is, the tensile strength was increased by 30%. The microwave process can make the oxidation of the PAN more complete, so the strength of the oxidized fiber bundle of the microwave process is slightly lower than the strength of the oxidized fiber bundle of the conventional electrothermal control process, which is more suitable for the microwave process of the oxidized fiber manufacturing method. Another evidence that the fiber bundle increases the degree of oxidation.  

Table II:  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Tensile Modulus (GPa) </td><td> Fiber Yarn bundle</td> <td> oxidized fiber yarn bundle</td><td> carbon fiber yarn bundle</td></tr><tr><td> Comparative Example 1 </td><td> 8.82 </td><td> 6.03 </td><td> 194.4 </td></tr><tr><td> Example 1 </td><td> 8.82 </td><td> 6.92 </td><td> 227.1 < /td></tr></TBODY></TABLE> From Table 2, the oxidized fiber yarn bundle produced in the microwave process of the first embodiment using the oxidized fiber manufacturing method is shown, and the carbon fiber yarn bundle finally carbonized The tensile modulus was 1.17 times that of Comparative Example 1 (227.1 divided by 194.4), that is, the tensile modulus was increased by 17%.  

So far, compared with the oxidized fiber yarn bundle which the conventional heating process acts on the fiber bundle, the creation shortens the 40 minutes required for the conventional heating process to 10 minutes, so that the process efficiency is increased by 3 times, and the process time is saved; Compared with the traditional heating process, the creation also increases the tensile strength of the carbon fiber yarn bundle by 30% and the tensile modulus by 17%; compared with the conventional heating process, the creation also applies the oxidized fiber yarn bundle 20A. The cross-sectional area of the oxide layer 211 of the oxidized fiber 21 is 99.0% or more of the cross-sectional area of the oxidized fiber 21, so that the core-core structure is not formed, so that the cross-section of the oxidized fiber bundle 20A tends to be uniform. Therefore, the tensile strength and tensile modulus of the carbon fiber yarn bundle can be improved. Therefore, this creation can enhance the performance of carbon fiber with a relatively more active and reliable means.

In the method for producing the oxidized fiber, in the implementation, the method for producing the oxidized fiber is preferably carried out by using a microwave focusing treatment of 24 kW/m ² for 5 to 10 minutes. Of course, the method for producing the oxidized fiber can also be subjected to the oxidized fiber manufacturing method by microwave focusing treatment of 24 kW/m ² for 5 to 10 minutes; and, as shown in FIG. 3 The conveying unit 30 is provided with the feeding unit 31 for supplying the fiber bundle 20, the winding unit 32 for continuously transporting the fiber yarn bundle 20, and the furnace body 33 for passing the fiber yarn bundle 20; The microwave processing unit 40 is provided with the magnetron 41 for generating microwaves at the furnace body 33, and the embodiment of the air supply unit 42 for introducing oxygen-containing gas into the furnace body 33. . The method for producing the oxidized fiber is applicable to the production of the carbon fiber yarn bundle by the fiber bundle 20 after passing through the furnace body 33 without being wound by the winding unit 32, but continuing the carbonization process, or for forming a roll. The fiber bundle 20 is unwound by the feeding unit 31 and is produced by the winding unit 32.

Of course, the oxidized fiber manufacturing method can also be applied to a batch production method. In the embodiment of the batch production mode, the following steps may be sequentially performed. As shown in Fig. 9, the oxidized fiber manufacturing method is suitable for pre-oxidizing the fiber bundle 20 into the oxidized fiber bundle 20A:

a yarn supplying step S01: preparing the fiber yarn bundle 20, the fiber yarn bundle 20 may be composed of a single fiber or a plurality of the fiber bundles; the fiber yarn bundle 20 may be polyacrylonitrile (PAN) One of fiber, asphalt fiber or other organic fiber;

a microwave processing step S02: exposing the fiber bundle 20 to the microwave condition, the microwave condition comprising: the microwave frequency, the microwave frequency is between 300 and 300,000 MHz; the microwave power, the microwave power is between 1 ~1000 kW/m ² ; the working temperature, the working temperature is between 100 and 600 ° C; the processing time, the processing time is between 1 and 40 minutes; and the gas atmosphere, the gas atmosphere is oxygen, air One of or one of ozone.

Furthermore, in the oxidized fiber manufacturing method, the microwave processing unit 40 is provided with the gas supply unit 42 for introducing an oxygen-containing gas into the furnace body 33, and the gas supply unit 42 is introduced into the furnace body. The oxygen-containing gas of 33 may be one of oxygen, air, ozone or a mixture thereof.

And the oxidized fiber manufacturing method, in the conveying unit 30, the feeding unit 31 for supplying the fiber bundle 20, the winding unit 32 for continuously transporting the fiber bundles 20, and the fiber bundle The furnace body 33 is passed through; the microwave processing unit 40 is provided with the magnetron 41 for generating microwaves at the furnace body 33, and the supply for supplying oxygen-containing gas into the furnace body 33. In the embodiment of the gas unit 42, the winding unit 32, the magnetron 41 and the gas supply unit 42 can be electrically connected to a control unit 50. The control unit 50 can control whether the winding unit 32, the magnetron 41 and the air supply unit 42 operate, and can set the rotation speed of the winding unit 32 according to the characteristics of the fiber bundle 20 or the product specifications processed. The operating parameters of the power of the magnetron 41 and the flow rate of the gas supply unit 42.

The oxidized fiber manufacturing method is provided in the conveying unit 30 with the feeding unit 31 for supplying the fiber bundle 20, the winding unit 32 for towing the fiber bundle 20, and the fiber bundle 20 for passing. In the embodiment of the furnace body 33, the heat transfer unit 34 can be further disposed inside the furnace body 33. As shown in FIG. 10, the heat storage effect of the heat retention unit 34 can be utilized to make the furnace The interior of the body 33 is maintained at a predetermined operating temperature and achieves energy savings. In Fig. 10, the supply unit 31 provides a plurality of the fiber bundles 20 arranged in parallel with each other into the furnace body 33.

In the method of manufacturing the oxidized fiber, the transfer unit 30 can be respectively disposed at the upper and lower positions of the transport path of the fiber bundle 20 in the interior of the furnace body 33 as shown in FIG. The unit 34; or as shown in Fig. 10, is provided inside the furnace body 33 with the heat retention unit 34 surrounding the conveying path of the fiber bundle 20, whereby the fiber bundle 20 is uniformly heated.

The oxidized fiber manufacturing method can be selected as one of metal oxide, carbide, microwave high-sensing material or a combination thereof in various possible implementations.

In the method of manufacturing the oxidized fiber, the microwave processing unit 40 can be respectively provided with the magnetron 41 at a position above and below the transport path with respect to the fiber bundle 20 as shown in FIG. Or the microwave processing unit 40 is provided with a plurality of the magnetrons 41 surrounding the transport path of the fiber bundle 20, so that the fiber bundle 20 is uniformly subjected to the microwave focusing process.

Please refer to FIG. 4 again, the oxidation degree of the oxidized fiber 21 is 89% after the fiber bundle 20 is irradiated at 220 ° C for 40 minutes by microwave focusing treatment with microwave power of 12 kW/m ² as described above; The oxidized fiber 21 is oxidized to 70% by a conventional heating process and the fiber bundle 20 is heated at 270 ° C for 40 minutes without a microwave process. Therefore, the oxidized fiber manufacturing method can achieve a higher degree of oxidation at a lower temperature than the conventional heating process, so that waste of heat energy can be avoided.

Please also refer to Table 3, which shows the fiber bundle 20, the oxidized fiber bundle 20A and its subsequent carbonization by the conventional process of heating the electric heating tube and the microwave process using the oxidized fiber manufacturing method. A comparison table of tensile strength of carbon fiber yarn bundles. In the conventional process of heating the electric heating tube, the process conditions are the temperature of the furnace body of 270 ° C, the treatment time is 40 minutes, and the obtained physical property results are listed as "Comparative Example 1"; the microwave process of the oxidized fiber manufacturing method described above, The process conditions are as follows: the furnace temperature is 220 ° C, the microwave frequency is 2450 MHz, the processing time is 40 minutes, and the physical property results obtained when the microwave power is 22 kW/m ² are listed as "Example 2", when the microwave power is 20 kW / property results m the results of the ^two as "third embodiment", when as the microwave power is property results 16kW / m ² the results of the "fourth embodiment", when the microwave power is 15 kW / m property results are ^two stars of Listed as "Embodiment 5". The fiber bundle 20 of Comparative Example 1 and all of the examples was made of polyacrylonitrile. Further, the cross section of the oxidized fiber 21 in the oxidized fiber bundle 20A of Comparative Example 1 and the respective examples was taken as a solid image by a scanning electron microscope (SEM), and the oxide layer was calculated. The cross-sectional area of 211 is divided by the cross-sectional area of the oxidized fiber 21, that is, the ratio of the oxidized layer 211 to the oxidized fiber 21, and is shown in Table 3.

Table 3:  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> number</td><td> Tensile strength (MPa) of the fiber bundle </td ><td> Microwave power kW/m²</td><td> Tensile strength (MPa) of carbon fiber yarn bundle </td><td> Ratio of tensile strength</td> <td> The cross-sectional area of the oxide layer divided by the cross-sectional area of the oxidized fiber</td></tr><tr><td> Comparative Example 1 </td><td> 865 </td><td> 0 </td><td> 2824 </td><td> 1 </td><td> 40% </td></tr><tr><td> Example 1 </td><td> 865 </td><td> 24 </td><td> 3675 </td><td> 1.30 </td><td> 99.0% </td></tr><tr><td> Example </td><td> 865 </td><td> 22 </td><td> 3580 </td><td> 1.27 </td><td> 91.3% </td></tr> <tr><td> Example 3</td><td> 865 </td><td> 20 </td><td> 3486 </td><td> 1.23 </td><td> 82.7% </td></tr><tr><td> Example 4</td><td> 865 </td><td> 16 </td><td> 3298 </td><td> 1.17 < /td><td> 61.5% </td></tr><tr><td> Example 5</td><td> 865 </td><td> 15 </td><td> 3204 < /td><td> 1.13 </td><td> 51.2% </td></tr></TBODY></TABLE> From Table 3, the fifth embodiment is used to apply the oxygen. The oxidized fiber yarn bundle produced by the microwave manufacturing method of the fiber manufacturing method has a tensile strength of the carbon fiber bundle after the final carbonization is 1.13 times that of the first comparative example, that is, the tensile strength is increased by 13%, and the oxide layer 211 is broken. The area of the area divided by the oxidized fiber 21 is 51.2%, that is, the oxide layer 211 accounts for 51.2% of the oxidized fiber 21; and the oxidized fiber produced by the microwave process using the oxidized fiber manufacturing method is used in the fourth embodiment. The yarn bundle, the tensile strength of the carbonized yarn bundle after the final carbonization is 1.17 times that of Comparative Example 1, that is, the tensile strength is increased by 17%, and the sectional area of the oxide layer 211 is divided by the sectional area of the oxidized fiber 21. The ratio is 61.5%, that is, the oxide layer 211 accounts for 61.5% of the oxidized fiber 21; the third embodiment uses the oxidized fiber yarn bundle made by the microwave process of the oxidized fiber manufacturing method, and the carbonized yarn bundle of the finally carbonized The tensile strength is 1.23 times that of the first comparative example, that is, the tensile strength is increased by 23%, and the cross-sectional area of the oxide layer 211 divided by the cross-sectional area of the oxidized fiber 21 is 82.7%, that is, the oxide layer 211 accounts for 82.7% of the oxidized fiber 21; use of the second embodiment The oxidized fiber yarn bundle produced by the microwave process of the oxidized fiber manufacturing method has a tensile strength of the carbon fiber bundle after the final carbonization is 1.27 times that of the first comparative example, that is, the tensile strength is increased by 27%, and the oxide layer 211 The cross-sectional area divided by the cross-sectional area of the oxidized fiber 21 is 91.3%, that is, the oxide layer 211 accounts for 91.3% of the oxidized fiber 21; and the oxidation of the oxidized fiber manufacturing method by the microwave process of the first embodiment is used. The fiber yarn bundle, the tensile strength of the carbonized yarn bundle after the final carbonization is 1.3 times that of the first comparative example, that is, the tensile strength is increased by 30%, and the sectional area of the oxide layer 211 is divided by the cross section of the oxidized fiber 21. The area is 99.0%, that is, the oxide layer 211 accounts for 99.0% of the oxidized fiber 21.  

Therefore, the oxidized fiber structure disclosed in the present invention comprises at least one oxidized fiber 21, wherein the oxidized fiber 21 comprises an oxide layer 211 and a core 212, and the oxide layer 211 is coated on the core The outer side of 212, wherein the oxide layer 211 accounts for at least 50% of the oxidized fiber 21, or the cross-sectional area of the oxide layer 211 accounts for at least 50% of the cross-sectional area of the oxidized fiber 21. As shown in Fig. 11, the oxide layer 211 accounts for at least 80% of the oxidized fiber 21, or the cross-sectional area of the oxide layer 211 accounts for at least 80% of the cross-sectional area of the oxidized fiber 21.

Of course, the oxidized fiber 21 disclosed in the present invention can be manufactured by using the fiber bundle 20 by any of the above-mentioned oxidized fiber manufacturing methods that may be implemented. Since the oxide layer 211 is formed under the microwave condition, The oxide layer 211 is a microwave oxide layer, and the oxide layer 211 of the oxidized fiber 21 among the oxidized fiber bundles 20A accounts for at least 50% of the oxidized fibers 21.

In practice, the fiber bundle 20 can be one of polyacrylonitrile (PAN), asphalt or other organic fibers. Of course, after the oxidized fiber is subjected to microwave focusing treatment of the fiber bundle 20 through a microwave of 24 kW/m ² for 10 minutes, the oxide layer 211 of the oxidized fiber 21 among the oxidized fiber bundle 20A occupies the oxidized fiber. 99.0% of 21, or the cross-sectional area of the oxide layer 211 accounts for 99.0% of the cross-sectional area of the oxidized fiber 21.

Compared with the conventional technology, the oxidized fiber disclosed in the present invention mainly uses the microwave focusing of the microwave processing unit to apply ultra-high-speed pre-oxidation treatment to the fiber yarn bundle, and the fiber yarn bundle is processed into an oxidized fiber yarn bundle, which can effectively reduce the fiber bundle. The oxidation time of the oxidized fiber yarn bundle, and the oxidized fiber in the oxidized fiber yarn bundle is subjected to microwave focusing oxidation treatment, at least 50% of the cross-sectional area of the oxidized fiber, thereby effectively reducing the core structure of the oxidized fiber, and even allowing The oxidized fiber has no obvious sheath core structure, and the carbon fiber performance is improved by a relatively more active and reliable means.

The embodiments described above are only for explaining the technical idea and characteristics of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement them according to the scope of the patent. That is, the equivalent changes or modifications made by the people in accordance with the spirit revealed by this creation should still be covered by the scope of the patent of this creation.

[Prior technology]
10‧‧‧Oxidized fiber
11‧‧‧Fiber
111‧‧‧Oxide layer
112‧‧‧ core
113‧‧‧ skin core interface
[This creation]
20‧‧‧Fiber yarn bundle
20A‧‧‧Oxidized fiber yarn bundle
21‧‧‧Oxidized fiber
211‧‧‧Oxide layer
212‧‧‧ core
30‧‧‧Transfer unit
31‧‧‧Feeding unit
32‧‧‧Winding unit
33‧‧‧ furnace body
331‧‧‧air inlet
332‧‧‧ air outlet
34‧‧‧Insulation unit
40‧‧‧Microwave processing unit
41‧‧‧Magnetron
42‧‧‧ gas supply unit
50‧‧‧Control unit
S01‧‧‧ provides yarn bundle steps
S02‧‧‧ microwave processing steps

Figure 1 is a schematic view of the sheath core structure of a conventional oxidized fiber. Figure 2 is a basic flow chart of the oxidized fiber manufacturing method of the present invention. Fig. 3 is a schematic view showing the structure of a transfer unit and a microwave processing unit of the oxidized fiber manufacturing method of the present invention. The fourth picture shows that the oxidized fiber manufacturing method of the present invention is treated with a microwave focusing treatment of 12 kW/m2, 16 kW/m2, 20 kW/m2, and 24 kW/m2, respectively, on the fiber bundle and the conventional heating process to the fiber bundle. The oxidation degree curve of the oxidized fiber. Fig. 5 is a graph showing the degree of cyclization of oxidized fibers of the fiber bundle after 2 minutes, 4 minutes, 5 minutes, 10 minutes, and 15 minutes of the fiber bundle treatment by the microwave focusing treatment of 24 kW/m2. Fig. 6 is a cross-sectional view of the oxidized fiber cross-section of the oxidized fiber yarn bundle produced by the oxidized fiber yarn bundle produced by the microwave concentrating treatment of the fiber bundle for 5 minutes by the microwave oxidizing method of 24 kW/m2. Fig. 7 is a cross-sectional view of the oxidized fiber cross-section of the oxidized fiber yarn bundle produced by the oxidized fiber yarn bundle produced by the microwave concentrating treatment of the fiber bundle for 10 minutes by the microwave oxidizing method of 24 kW/m2. Fig. 8 is a cross-sectional view of the oxidized fiber cross-section of the oxidized fiber yarn bundle produced by the oxidized fiber yarn bundle produced by the method of oxidizing fiber production of the present invention with a microwave focusing treatment of 24 kW/m2 for 15 minutes. Figure 9 is another flow chart of the oxidized fiber manufacturing method of the present invention. Fig. 10 is a schematic view showing the structure of the furnace body of the oxidized fiber manufacturing method of the present invention. Figure 11 is a schematic view of the structure of the present oxidized fiber.

Claims (7)

An oxidized fiber structure comprising at least one oxidized fiber (21), wherein the oxidized fiber (21) further comprises an oxide layer (211) and a core portion (212), the oxide layer (211) is wrapped Covering the outer side of the core portion (212), the cross-sectional area of the oxide layer (211) is at least 50% or more of the cross-sectional area of the oxidized fiber (21). The oxidized fiber structure according to claim 1, wherein the oxide layer (211) has a cross-sectional area of at least 60% or more of the cross-sectional area of the oxidized fiber (21). The oxidized fiber structure according to claim 1, wherein the cross-sectional area of the oxide layer (211) accounts for at least 80% or more of the cross-sectional area of the oxidized fiber (21). The oxidized fiber structure according to claim 1, wherein the oxide layer (211) has a cross-sectional area of at least 90% or more of the cross-sectional area of the oxidized fiber (21). The oxidized fiber structure according to claim 1, wherein the oxide layer (211) has a cross-sectional area of at least 99% or more of the cross-sectional area of the oxidized fiber (21). The oxidized fiber structure of claim 1, wherein the oxidized fiber (21) is made by exposing a fiber to the microwave condition. The oxidized fiber structure according to claim 6, wherein the oxidized fiber (21) is an organic fiber.