CN116479557A - Method for preparing large-size tow carbon fibers by spinning - Google Patents
Method for preparing large-size tow carbon fibers by spinning Download PDFInfo
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- CN116479557A CN116479557A CN202310330274.6A CN202310330274A CN116479557A CN 116479557 A CN116479557 A CN 116479557A CN 202310330274 A CN202310330274 A CN 202310330274A CN 116479557 A CN116479557 A CN 116479557A
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- carbon fiber
- tow
- desizing
- tow carbon
- spinning
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- 229920000049 Carbon (fiber) Polymers 0.000 title claims abstract description 76
- 239000004917 carbon fiber Substances 0.000 title claims abstract description 76
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000009987 spinning Methods 0.000 title claims abstract description 24
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 52
- 238000009990 desizing Methods 0.000 claims abstract description 28
- 238000011282 treatment Methods 0.000 claims abstract description 26
- 238000001035 drying Methods 0.000 claims abstract description 19
- 238000004513 sizing Methods 0.000 claims abstract description 19
- 238000005406 washing Methods 0.000 claims abstract description 14
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 13
- 229920002239 polyacrylonitrile Polymers 0.000 claims abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 11
- 238000004804 winding Methods 0.000 claims abstract description 7
- 239000011261 inert gas Substances 0.000 claims abstract description 3
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical group C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 claims description 14
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 238000003825 pressing Methods 0.000 claims description 4
- 238000005979 thermal decomposition reaction Methods 0.000 claims description 4
- 229920006395 saturated elastomer Polymers 0.000 claims description 3
- 239000003822 epoxy resin Substances 0.000 claims description 2
- 229920000647 polyepoxide Polymers 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 description 11
- 239000000835 fiber Substances 0.000 description 8
- 238000003763 carbonization Methods 0.000 description 6
- 239000002243 precursor Substances 0.000 description 6
- 239000002002 slurry Substances 0.000 description 5
- 239000002131 composite material Substances 0.000 description 3
- 238000002166 wet spinning Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 1
- 239000007900 aqueous suspension Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000009998 heat setting Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000011550 stock solution Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 238000010557 suspension polymerization reaction Methods 0.000 description 1
- 238000003856 thermoforming Methods 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
- D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
- D02G3/00—Yarns or threads, e.g. fancy yarns; Processes or apparatus for the production thereof, not otherwise provided for
- D02G3/02—Yarns or threads characterised by the material or by the materials from which they are made
- D02G3/16—Yarns or threads made from mineral substances
-
- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
- D06B13/00—Treatment of textile materials with liquids, gases or vapours with aid of vibration
-
- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
- D06B15/00—Removing liquids, gases or vapours from textile materials in association with treatment of the materials by liquids, gases or vapours
-
- D—TEXTILES; PAPER
- D10—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
- D10B—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
- D10B2101/00—Inorganic fibres
- D10B2101/10—Inorganic fibres based on non-oxides other than metals
- D10B2101/12—Carbon; Pitch
Abstract
The invention discloses a method for preparing large-size tow carbon fibers by spinning, which comprises the following steps: step S1: and (3) placing a plurality of small-tow polyacrylonitrile-based carbon fibers containing sizing agents in a desizing furnace for desizing treatment under the inert gas atmosphere, and controlling the desizing temperature and the desizing time to obtain the small-tow carbon fiber desized yarn. Step S2: and superposing and combining the prepared multiple bundles of small tow desized filaments to obtain the required large-specification tow carbon fibers. Step S3: and (3) sequentially carrying out water washing, water washing and drying, sizing and drying treatment on the large-specification tow carbon fibers after spinning, and winding to prepare the required large-specification tow carbon fiber product. The invention can freely combine small-tow carbon fibers and mix silk to prepare different types of large-specification carbon fiber products, meets the different market demands of different application fields, and reflects the flexibility and adaptability of preparing large-specification tow products.
Description
Technical Field
The invention relates to the technical field of carbon fiber material preparation, in particular to a method for preparing large-specification tow carbon fibers by using synthetic yarns.
Background
Carbon fiber is the main material of carbon fiber composite material, has characteristics such as high strength, high modulus, corrosion resistance, is widely used in fields such as gas cylinder, wind power, photovoltaic, sports and leisure. With the continuous development and innovation of the carbon fiber industry, advanced carbon fiber enterprises abroad develop carbon fibers with different types and different performances, and from the K number, the carbon fibers have the types of 6K, 12K, 24K, 36K, 48K, other K and the like. Compared with the development of the carbon fiber industry in China, the development of the carbon fiber industry in China is late, the product types with high carbon fiber performance and stable production at present are mainly concentrated on small tows (3K, 6K, 12K and 24K), and the preparation of the high-performance large-specification tow carbon fiber has important significance for the differential requirements of composite materials in various application fields.
Chinese patent 20201102570. X discloses a spinning pack for large tow carbon fiber precursors and a method for preparing polyacrylonitrile-based large tow carbon fiber precursors, the method comprising: 1) The method comprises the steps of (1) obtaining a polyacrylonitrile polymer by adopting an acrylonitrile aqueous suspension polymerization process, dissolving the polymer in a solvent, removing bubbles and filtering impurities to obtain a polyacrylonitrile spinning solution; 2) A spinning component for large-tow carbon fiber precursors is used, and the spinning component consists of a combined filter screen, a pre-distributing plate, a distributing plate and a spinneret plate. The stock solution is extruded uniformly in the radial direction on the spinneret plate surface, and the primary fiber is obtained after solidification molding; 3) The primary fiber is subjected to drawing, washing, hot drawing, pre-oiling, drying densification, post-oiling, heat setting and filament collection to obtain the large-tow carbon fiber precursor. The related spinning component solves the problem that after the diameter of a large-tow spinneret plate above 24K is enlarged, the radial extrusion pressure on the spinneret plate surface is uneven, so that the influence on the fiber performance is caused, the large-tow spinneret plate surface is free from broken filaments and floating filaments, the deviation of the fineness of the raw filaments is 0-3.0%, and various performance indexes of the raw filaments and the industrialized stable production are improved.
Chinese patent 202111646223.1 discloses a 35k large tow carbon fiber and a preparation method thereof, wherein the preparation method comprises the following steps: under the air atmosphere, placing the 35K big-tow polyacrylonitrile copolymer fiber in an oxidation furnace for pre-oxidation treatment to obtain 35K big-tow carbon fiber pre-oxidized fiber, performing low-temperature carbonization treatment on the 35K big-tow carbon fiber pre-oxidized fiber, performing high-temperature carbonization treatment on the 35K big-tow carbon fiber pre-oxidized fiber subjected to the low-temperature carbonization treatment, performing surface treatment, sizing, drying and other treatments on the 35K big-tow carbon fiber pre-oxidized fiber subjected to the high-temperature carbonization treatment to obtain 35K big-tow polyacrylonitrile carbon fiber, and placing the prepared 35K big-tow polyacrylonitrile carbon fiber sample in a detection reagent for gum dipping and curing to perform mechanical property test. The 35k large-tow carbon fiber and the preparation method thereof can effectively solve the problems of the preoxidation and the preoxidation of the large-tow sheath-core structure, improve the production efficiency of carbon fiber composite material application and reduce the production cost.
Disclosure of Invention
The invention adopts the high-performance small-tow carbon fiber (3K, 6K, 12K or 24K) with stable domestic commodity supply on the selection of raw materials, and solves the problems that the preparation of large-gram-weight large-tow polyacrylonitrile precursor is difficult and the corresponding carbonization is complex in the production and preparation process of large-specification tows. From the perspective of preparing different large-specification (30K, 36K, 48K and the like) tow carbon fiber products, small tows can be freely combined and combined to prepare different types of products, so that the method is suitable for application requirements of different markets, has flexibility and adaptability of preparing products, and meets market and creation values.
The technical scheme adopted by the invention is a method for preparing large-specification tow carbon fibers by spinning, and the preparation method comprises the following steps:
step S1: and (3) placing a plurality of small-tow polyacrylonitrile-based carbon fibers containing sizing agents in a desizing furnace for desizing treatment under the inert gas atmosphere, and controlling the desizing temperature and the desizing time to obtain the small-tow carbon fiber desized yarn.
Step S2: and superposing and combining the prepared multiple bundles of small tow desized filaments to obtain the required large-specification tow carbon fibers.
Step S3: and (3) sequentially carrying out water washing, water washing and drying, sizing and drying treatment on the large-specification tow carbon fibers after spinning, and winding to prepare the required large-specification tow carbon fiber product.
The sizing agent in the step S1 is epoxy resin, and the thermal decomposition temperature is less than 600 ℃. The draft ratio of the desizing treatment in the step S1 is 0.98-1.02, the draft ratio of the stacked adduct yarn in the step S2 is 1.0-1.02, the draft ratio of the washing treatment in the step S3 is 0.96-1.0, and the draft ratio of the drying treatment in the step S3 is 1.0-1.02.
The sizing agent is preferably bisphenol A type, and the thermal decomposition temperature is less than 380 ℃.
In the step S1, 4 temperature gradient desizing furnaces are adopted, wherein the temperature interval in the desizing furnaces is 400-700 ℃, and the gradient temperature difference of each temperature area is 50-100 ℃.
The production speed of the desizing furnace in the step S1 is 8-10 m/min, and the desizing time is 0.5-1.0 min.
The washing treatment in the step S3 is in a mode of combining ultrasonic wave and compressed air.
The ultrasonic wave adopts a frequency adjustable mode, and the preferable adjusting frequency is 25-30 KHz.
The compressed air is introduced from the bottom up to the vertical carbon fiber tows, and the preferred pressure is 0.2-0.3 MPa.
In the step S3, 2 series contact type drying rollers are adopted for drying treatment, the heat source is saturated steam with the pressure of 0.3-0.5 MPa, and the water content of the carbon fiber is controlled to be below 0.1%.
And a heat conducting oil press roller is arranged right above the 2 nd contact type drying roller connected in series, the temperature is adjustable at normal temperature to 150 ℃, the pneumatic pressing pressure of the press roller is adjustable at 0.1 to 0.3MPa, and the combined large-size tows are extruded and thermoformed.
The beneficial effects of the invention are that
1. The invention adopts the high-performance small-tow carbon fiber with stable domestic supply as the raw material, and does not need to prepare large gram weight and large-tow polyacrylonitrile precursor and the corresponding carbonization process.
2. According to the invention, 4 temperature gradient desizing furnaces are adopted, and sizing agents carried in small-tow carbon fiber products can be effectively removed through the matching of the desizing temperature and the technological parameters of the desizing time.
3. The invention combines desized silk stacking and silk adding, ultrasonic wave and compressed air combined water washing treatment and drying extrusion thermoforming, can effectively combine a plurality of small silk bundle carbon fibers together, meets the different market demands of different application fields, and reflects the flexibility and adaptability of preparing large-specification silk bundle products.
Detailed Description
Comparative example 1: the 48K carbon fiber is wet spun, the tensile strength is 4300MPa, the tensile modulus is 250GPa, the elongation at break is 1.7%, and the linear density is 3200g/km.
Comparative example 2: the 48K carbon fiber is wet spun, the tensile strength is 4480MPa, the tensile modulus is 234GPa, the elongation at break is 1.9%, and the linear density is 3200g/km.
Example 1: 4 dry-jet wet-spinning 12K carbon fibers (the product performance is that the tensile strength is 4990MPa, the tensile modulus is 244GPa, the elongation at break is 2.0%, the linear density is 806g/km, the sizing agent type is bisphenol A, the slurry content is 1.09%), the temperature zone of a desizing furnace 4 is set at 400 ℃/450 ℃/500 ℃/550 ℃, the production speed is 10m/min, the desizing time is 0.6min, the ultrasonic frequency of water washing is 26KHz, the compressed air pressure is 0.25MPa, the saturated steam pressure of a contact drying roller is 0.3MPa, the temperature of a heat conduction oil pressure roller is 135 ℃, the pneumatic pressing pressure of a pressing roller is 0.18MPa, the draft ratio of the desizing treatment is 1.0, the draft ratio of the stacked sizing yarn is 1.0, the draft ratio of the water washing treatment is 0.96, the draft ratio of the sizing drying treatment is 1.01, the tensile strength of the 48K carbon fibers prepared by winding is 4450MPa, the tensile modulus is 248MPa, the elongation at break is 1.8%, and the linear density is 3212g/km.
Example 2: 2 dry-jet wet-spinning 24K carbon fibers (the product performance is that the tensile strength is 4970MPa, the tensile modulus is 238GPa, the elongation at break is 2.0%, the linear density is 1607g/km, the sizing agent type is bisphenol A, the slurry content is 1.08%), the same spinning preparation process is adopted, the tensile strength of the 48K carbon fibers prepared by winding is 4440MPa, the tensile modulus is 247MPa, the elongation at break is 1.8%, and the linear density is 3204g/km.
Example 3: 3 dry-jet wet-spinning 12K carbon fibers (the product performance is that the tensile strength is 4990MPa, the tensile modulus is 244GPa, the elongation at break is 2.0%, the linear density is 806g/km, the sizing agent type is bisphenol A, the slurry content is 1.09%), the same spinning preparation process is adopted, and the 36K carbon fibers prepared by winding have the tensile strength of 4678MPa, the tensile modulus of 248MPa, the elongation at break is 1.9%, and the linear density is 2420g/km.
Example 4: 1 dry-jet wet-spun 12K carbon fiber (the product performance is that the tensile strength is 4990MPa, the tensile modulus is 244GPa, the elongation at break is 2.0 percent, the linear density is 806g/km, the sizing agent type is bisphenol A, the slurry content is 1.09 percent) and 1 dry-jet wet-spun 24K carbon fiber (the product performance is that the tensile strength is 4970MPa, the tensile modulus is 238GPa, the elongation at break is 2.0 percent, the linear density is 1607g/km, the sizing agent type is bisphenol A, the slurry content is 1.08 percent), and the 36K carbon fiber prepared by winding is 4740MPa, the tensile modulus is 249MPa, the elongation at break is 1.9 percent and the linear density is 2407g/km by adopting the same synthetic yarn preparation technology.
Claims (10)
1. The method for preparing the large-size tow carbon fiber by the spinning is characterized by comprising the following steps of:
step S1: placing a plurality of small-tow polyacrylonitrile-based carbon fibers containing sizing agent in a desizing furnace for desizing treatment under the inert gas atmosphere, and controlling the desizing temperature and the desizing time to prepare small-tow carbon fiber desized filaments;
step S2: overlapping and combining the prepared multiple bundles of small tow desized filaments to obtain the required large-specification tow carbon fibers;
step S3: and (3) sequentially carrying out water washing, water washing and drying, sizing and drying treatment on the large-specification tow carbon fibers after spinning, and winding to prepare the required large-specification tow carbon fiber product.
2. The method for preparing large-size tow carbon fiber by spinning according to claim 1, wherein the method comprises the following steps: the sizing agent contained in the step S1 is epoxy resin, and the thermal decomposition temperature is less than 600 ℃; the draft ratio of the desizing treatment in the step S1 is 0.98-1.02, the draft ratio of the stacked adduct yarn in the step S2 is 1.0-1.02, the draft ratio of the washing treatment in the step S3 is 0.96-1.0, and the draft ratio of the drying treatment in the step S3 is 1.0-1.02.
3. The method for preparing large-size tow carbon fiber by spinning according to claim 2, wherein the method comprises the following steps: the sizing agent is bisphenol A type, and the thermal decomposition temperature is less than 380 ℃.
4. The method for preparing large-size tow carbon fiber by spinning according to claim 1, wherein the method comprises the following steps: in the step S1, 4 temperature gradient desizing furnaces are adopted, wherein the temperature interval in the desizing furnaces is 400-700 ℃, and the gradient temperature difference of each temperature area is 50-100 ℃.
5. The method for preparing large-size tow carbon fiber by spinning according to claim 1, wherein the method comprises the following steps: the production speed of the desizing furnace in the step S1 is 8-10 m/min, and the desizing time is 0.5-1.0 min.
6. The method for preparing large-size tow carbon fiber by spinning according to claim 1, wherein the method comprises the following steps: the washing treatment in the step S3 is in a mode of combining ultrasonic wave and compressed air.
7. The method for preparing large-size tow carbon fiber by spinning according to claim 6, wherein the method comprises the following steps: the ultrasonic wave adopts a frequency adjustable mode, and the adjusting frequency is 25-30 KHz.
8. The method for preparing large-size tow carbon fiber by spinning according to claim 6, wherein the method comprises the following steps: the compressed air is introduced from the bottom to the top and vertical to the carbon fiber tows, and the introducing pressure is 0.2-0.3 MPa.
9. The method for preparing large-size tow carbon fiber by spinning according to claim 1, wherein the method comprises the following steps: in the step S3, 2 series contact type drying rollers are adopted for drying treatment, the heat source is saturated steam with the pressure of 0.3-0.5 MPa, and the water content of the carbon fiber is controlled to be below 0.1%.
10. The method for preparing large-size tow carbon fiber by spinning according to claim 9, wherein the method comprises the following steps: and a heat conducting oil press roller is arranged right above the 2 nd contact type drying roller connected in series, the temperature is adjustable at normal temperature to 150 ℃, the pneumatic pressing pressure of the press roller is adjustable at 0.1 to 0.3MPa, and the combined large-size tows are extruded and thermoformed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310330274.6A CN116479557A (en) | 2023-03-30 | 2023-03-30 | Method for preparing large-size tow carbon fibers by spinning |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310330274.6A CN116479557A (en) | 2023-03-30 | 2023-03-30 | Method for preparing large-size tow carbon fibers by spinning |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116479557A true CN116479557A (en) | 2023-07-25 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202310330274.6A Pending CN116479557A (en) | 2023-03-30 | 2023-03-30 | Method for preparing large-size tow carbon fibers by spinning |
Country Status (1)
| Country | Link |
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| CN (1) | CN116479557A (en) |
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2023
- 2023-03-30 CN CN202310330274.6A patent/CN116479557A/en active Pending
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