A device and method for stabilizing high-solids-content, low-viscosity spinning solution

Abstract

This invention relates to a device and method for stabilizing high-solids-content, low-viscosity spinning solutions. The device includes a spinning solution compounding unit and a shear stabilization unit. The spinning solution compounding unit includes a spinning solution compounding tank and, on the tank, a main inlet, a hollow stirring rod, a secondary inlet, an outlet, a stirring paddle on the stirring rod, and a main motor for driving the stirring paddle. The stirring paddle has a branched hollow flow channel. The main inlet is located at the end of the hollow stirring rod, and the branched hollow flow channel communicates with the hollow stirring rod. The shear stabilization unit includes a spinning flow channel connected to the outlet, a shear screw in the spinning flow channel, a secondary motor for driving the shear screw, and a nozzle at the bottom of the spinning flow channel. Compared with the prior art, this invention can achieve uniform and stable production of organic and inorganic spinning solutions, ensuring the smooth progress of subsequent spinning processes.

Description

Technical Field

[0001] This invention relates to the field of spinning technology, and in particular to a device and method for stabilizing high-solids-content, low-viscosity spinning solutions. Background Technology

[0002] As a strategic basic material, fiber plays a vital role in aerospace, petrochemicals, equipment manufacturing, and new energy fields. Spinning solutions, as raw materials for fiber preparation, are generally divided into two main categories: organic solutions and inorganic solutions. Their stability, spinnability, and fiber performance are closely related. Currently, organic solutions are generally polymer spinning solutions with a unimodal molecular weight distribution. Fiber membranes prepared from low-molecular-weight polymer spinning solutions have poor mechanical properties, making them difficult to meet practical application requirements. High-molecular-weight polymer solutions, on the other hand, have high viscosity, low solid content, and low fiber formation rate. Inorganic spinning solutions have unstable rheological properties; their viscosity changes continuously with time and temperature, making it difficult to precisely control the diameter and size of the resulting fibers. This places higher demands on the precision of spinning solution preparation equipment to accurately control the spinning process. Furthermore, spinning solutions are prone to gelation over time during processing, clogging spinning channels and nozzles, severely affecting production continuity.

[0003] To overcome the defects in the preparation of spinning solutions mentioned above, researchers have conducted in-depth studies on organic and inorganic spinning solutions. Patent ZL202110359248.7 discloses a high-solids-content, low-viscosity polyacrylonitrile suspension, its preparation method and application, and a method for preparing polyacrylonitrile-based carbon fibers. This method involves mixing a first auxiliary monomer, a second auxiliary monomer, a polymerization medium, an initiator, and a chain transfer agent to obtain a high-solids-content, low-viscosity polyacrylonitrile suspension. However, the solution obtained by this method is a suspension with poor uniformity and stability, and it is not applicable to other organic solutions, lacking universality. Patent CN202211337139.6 discloses a polyacrylonitrile sodium thiocyanate spinning solution, its preparation method and application, as well as a spinning method and polyacrylonitrile precursor fiber. This method involves dispersing polyacrylonitrile in a first sodium thiocyanate aqueous solution and placing it in a carbon dioxide atmosphere, then adding a second sodium thiocyanate aqueous solution, and mixing by introducing carbon dioxide and pressurizing and heating to a supercritical state to obtain the polyacrylonitrile sodium thiocyanate spinning solution. This method is complex to operate, has a long process cycle, and is not suitable for large-scale preparation of spinning solutions. Patent ZL202111269140.5 discloses a flexible, high-strength silica nanofiber membrane and its preparation method. It modulates the hydrolysis process of the silicon source by introducing an alcohol solvent and increases the solubility of polyvinylpyrrolidone in the solvent system, obtaining a spinning solution with high solids content. However, the polymer introduced into this inorganic spinning solution significantly reduces the content of inorganic components. Patent ZL202311577801.X discloses alumina ceramic nanofiber aerogel with high solids content inorganic alumina sol and its preparation method. It prepares alumina ceramic fibers by adding spinning aids and additives to the inorganic sol, with an alumina content of 15-30 wt% in the inorganic sol. However, the use of spinning aids and additives in this method significantly reduces fiber quality.

[0004] Therefore, there is a need to invent a device and method for stabilizing spinning solutions with high solids content and low viscosity, which is suitable for the uniform and stable mass production of organic and inorganic spinning solutions, thereby improving spinning efficiency and fiber yield. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art by providing a device and method for stabilizing high solids content and low viscosity spinning solutions, which can achieve uniform and stable production of organic and inorganic spinning solutions to ensure the smooth progress of subsequent spinning processes.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] The first aspect of this invention provides an apparatus for preparing a high-solids-content, low-viscosity spinning solution, comprising a spinning solution compounding device and a shear stabilization device, wherein specifically:

[0008] A spinning solution compounding device includes a spinning solution compounding tank and the following components disposed on the spinning solution compounding tank: a main inlet, a hollow stirring rod, a secondary inlet, an outlet, a stirring paddle disposed on the stirring rod, and a main motor for driving the stirring paddle. The stirring paddle is provided with a branch-shaped hollow flow channel. The main inlet is located at the end of the hollow stirring rod, and the branch-shaped hollow flow channel is connected to the hollow stirring rod.

[0009] The shear stabilization device includes a spinning channel connected to the liquid outlet, a shearing screw disposed in the spinning channel, an auxiliary motor for driving the shearing screw, and a nozzle disposed at the bottom of the spinning channel.

[0010] Furthermore, the inner wall of the spinning solution compounding tank is provided with a diamond-shaped baffle, and the plane of the diamond-shaped baffle is parallel to the axis of the hollow stirring rod;

[0011] The rhomboid baffles and the stirring paddle are spaced apart along the axial direction of the hollow stirring rod.

[0012] Furthermore, the stirring rod is provided with multiple stirring blades along the axial direction, wherein the lower surface of the lowest stirring blade is a downwardly convex arc-shaped structure.

[0013] Furthermore, the branch-shaped hollow flow channel includes a main flow channel communicating with the interior of the hollow stirring rod and multiple branch flow channels respectively connected to the main flow channel, and the branch flow channels are connected to the spinning solution compounding tank.

[0014] Furthermore, the spinning solution compounding device also includes a filter disposed on the spinning solution compounding tank, and the filter is connected to the spinning channel through a liquid supply pipe.

[0015] Furthermore, the shear stabilization device also includes a speed increaser, the auxiliary motor is connected to the speed increaser via a coupling, and the speed increaser is connected to the shear screw via a drive screw;

[0016] The speed increaser is a variable gear speed increaser;

[0017] The shearing action of the screw controls the uniformity and flowability of the spinning solution, and ensures the internal pressure rotation of the screw, thereby smoothly supplying the spinning solution to the nozzle.

[0018] A second aspect of the present invention provides a method for preparing a high-solids-content, low-viscosity spinning solution using the spinning solution preparation apparatus described above, comprising the following steps:

[0019] By blending polymer solutions with different molecular weights at equal viscosities, a high-low molecular weight bimodal spinning solution formulation was designed to obtain a high-solids-content, low-viscosity organic spinning solution. The high molecular weight polymer was introduced into the stirring paddle and the branched hollow flow channel through the main inlet, and finally into the spinning solution blending device. The low molecular weight polymer and solvent were introduced into the spinning solution blending device through the auxiliary inlet to carry out physicochemical reactions. After passing through the spinning solution blending device and the shear stabilization device, a high-solids-content, low-viscosity organic spinning solution was obtained. The solid content of the organic spinning solution was 20-60 wt%, and the viscosity was 300-1000 mPa·s.

[0020] By adjusting the amount and rate of water-alcohol mixture addition, the hydrolysis and condensation reaction rates of inorganic alkoxides can be precisely controlled to obtain inorganic spinning solutions with high inorganic component content. The water-alcohol mixture and acids are introduced into the stirring paddle and branched hollow flow channel through the main inlet, while the metal alkoxides are introduced into the spinning solution compounding device through the auxiliary inlet for physicochemical reactions. After passing through the spinning solution compounding device and shear stabilization device, a solution with high inorganic component content is obtained. The solid content in the inorganic spinning solution is 40-70 wt%, and the viscosity is 20-600 mPa·s.

[0021] Furthermore, the conditions for the physicochemical reaction are as follows: stirring is carried out under constant temperature conditions, namely 20–100°C, stirring conditions are 100–1000 rpm, and reaction time is 2–14 h.

[0022] Furthermore, for the preparation of high-solids-content, low-viscosity organic polymer spinning solutions, the high molecular weight polymer introduced into the main inlet is selected from one or more combinations of polyethylene, polystyrene, polypropylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, polyurethane, polybutylene butyrate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyethersulfone, ethylene-vinyl acetate copolymer, and polysulfone, with a molecular weight of 350,000 to 1,000,000.

[0023] For the preparation of spinning solutions with high inorganic component content, the solvents such as water-alcohol mixtures introduced into the main inlet are selected from one or more combinations of water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, chloroplatinic acid hexahydrate, acetone, benzene, toluene, xylene, diethyl ether, acetylacetone, acetone, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, benzene, toluene, xylene, and styrene; the acids are selected from one or more combinations of oxalic acid, acetic acid, and citric acid.

[0024] Furthermore, for the preparation of high-solids-content, low-viscosity organic polymer spinning solutions, the low molecular weight polymer in the secondary inlet is selected from one or more combinations of polyethylene, polystyrene, polypropylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, polyurethane, polybutylene butyrate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyethersulfone, ethylene-vinyl acetate copolymer, and polysulfone; the solvent is selected from water, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethylformamide. One or more of the following: N-methylpyrrolidone, acetone, acetylacetone, benzene, toluene, xylene, styrene, pentane, methane, octane, cyclohexane, cyclohexanone, methyl ethyl ketone, chlorobenzene, dichlorobenzene, dichloromethane, trichloroethylene, carbon tetrachloride, tetrachloroethane, carbon tetrachloride, chloroform, formic acid, phosphoric acid, glacial acetic acid, hydrochloric acid, ethyl acetate, amyl acetate, tetrahydrofuran, methanol, ethanol, isopropanol, ethylene glycol, diethyl ether, and propylene oxide, with a molecular weight of 50,000 to 300,000;

[0025] For spinning solutions with high inorganic component content, the inorganic alkoxide at the secondary inlet is selected from one or more combinations of tetraethyl orthosilicate, methyl silicate, hexachlorosilane, methyltriethoxysilane, tetramethoxysilane, 3-aminopropyltriethoxysilane, methyltrimethoxysilane, dimethoxydimethylsilane, trimethylchlorosilane, dimethoxymethane, aluminum isopropoxide, aluminum sec-butoxide, aluminum tert-butoxide, aluminum chloride hexahydrate, aluminum nitrate, aluminum chloride, zirconium acetylacetonate, zirconium acetate, zirconium n-propoxide, zirconium n-butoxide, zirconium nitrate pentahydrate, zirconium oxynitrate hydrate, titanium tetramethanol, zirconium oxychloride, basic zirconium carbonate, tetrabutyl titanate, titanium trichloride, tetraethyl titanate, and titanium tetraethanol.

[0026] The technical principle of this invention is as follows:

[0027] The present invention relates to a device and method for stabilizing high solids content and low viscosity spinning solution, which involves the preparation and stabilization of high solids content and low viscosity organic solution and high inorganic component content solution. It is achieved by using high and low molecular weight polymer compounding, differential coordination modification of inorganic alkoxides, and shear stirring process.

[0028] The principle of preparing and stabilizing high-solids-content, low-viscosity organic solutions of the present invention is as follows:

[0029] High-solids-content, low-viscosity organic solutions are formulated by blending low-molecular-weight polymers as the main component and high-molecular-weight homologous polymers as auxiliary components. This is because low-molecular-weight polymer spinning solutions have high solids content and high fiber conversion rates, which is beneficial for spinning, but their mechanical properties are poor; while high-molecular-weight polymer spinning solutions have low solids content but poor mechanical properties. By blending high-molecular-weight and low-molecular-weight polymers, the solids content of the solution can be significantly increased while ensuring the mechanical strength of the fiber membrane. Furthermore, during the blending process, the slow addition of high-molecular-weight polymers is controlled by a branched hollow flow channel, and the impact dispersion of the high-molecular-weight polymers is promoted by the staggered shear reinforcement effect between the agitator and the rhomboid baffles. The process achieves thorough and uniform mixing between high-molecular-weight polymers and low-molecular-weight polymers to obtain a transparent solution. Subsequently, a filter is used to remove air bubbles generated inside the solution during the compounding process to ensure that the solution entering the flow channel is bubble-free, reducing the discontinuity of the subsequent spinning process. After the solution enters the shear stabilization device, the screw in the spinning flow channel continuously rotates under internal pressure, so that the solution is in a state of continuous shearing and stirring before spinning, to ensure the uniformity and stability of the spinning solution and avoid the gelation phenomenon of the spinning solution, thereby obtaining an organic solution with high solid content, low viscosity, uniform stability and strong spinnability.

[0030] The principle of preparing and stabilizing solutions with high inorganic component content in this invention is as follows:

[0031] Solutions with high inorganic component content are primarily based on hydrolyzable metal alkoxides, which undergo spontaneous coordination, hydrolysis, and condensation reactions through water-alcohol mixtures and chelating agents. This is because metal alkoxides are readily soluble in alcohol solvents. By adding a non-polar solvent, the adsorption of the hydroxyl groups of the alcohol solvent onto the central atom of the alkoxide can be effectively reduced, ensuring the smooth progress of coordination and other reactions. Furthermore, the rapid addition and uneven dispersion of non-solvents can cause localized, excessively rapid hydrolysis and condensation in the solution, forming a gel-like substance. Therefore, during the compounding process of the spinning solution, the slow addition of the water-alcohol mixture is controlled by the branch-shaped hollow flow channel inside the agitator. Combined with the shear enhancement effect of the agitator and the rhombic baffle, the impact dispersion of the water-alcohol mixture is promoted, achieving a thorough and uniform mixing between the metal alkoxide and the water-alcohol mixture to obtain a transparent solution. Subsequently, a filter is used to remove the air bubbles generated inside the solution during the compounding process to ensure that the solution entering the flow channel is bubble-free, reducing the discontinuity of the subsequent spinning process. After the solution enters the shear stabilization device, the screw in the spinning flow channel continuously rotates under internal pressure, so that the solution is in a state of continuous shearing and stirring before spinning, to ensure the uniformity and stability of the spinning solution and avoid gelation of the spinning solution, thereby obtaining an inorganic solution with high inorganic component content, uniform stability, and strong spinnability.

[0032] Compared with the prior art, the present invention has the following technical advantages:

[0033] (1) The present invention provides a device and method for stabilizing a high solid content and low viscosity spinning solution. By using a blend of high and low molecular weight polymers, the solution can be made to have the advantages of low molecular weight polymers having low viscosity and being easy to spin, and high molecular weight polymers having high solid content and strong mechanical properties, thereby obtaining an organic spinning solution with both high solid content and low viscosity characteristics.

[0034] (2) The present invention provides a high solids content and low viscosity spinning solution stabilization device and method, which stabilizes the coordination, hydrolysis and condensation reactions of the spinning solution by finely controlling the reaction rate of the water-alcohol mixture, thereby reducing the risk of local gelation and unstable performance of the spinning solution and obtaining an inorganic spinning solution with high inorganic component content.

[0035] (3) The present invention provides a high solids content and low viscosity spinning solution stabilization device and method, which utilizes a solution compounding device, a filtration device and a shear stabilization device to achieve uniform and stable dispersion throughout the solution, thereby obtaining a long-term stable solution that can be applied on a large scale and has good universality. Attached Figure Description

[0036] Figure 1 This is an overall schematic diagram of a high-solids-content, low-viscosity spinning solution stabilization device according to the present invention.

[0037] In the diagram: 1. Main inlet; 2. Secondary inlet; 3. Motor; 4. Drive rod; 5. Speed ​​increaser; 6. Agitator; 7. Branch-shaped hollow flow channel; 8. Arc-shaped flow channel; 9. Diamond-shaped baffle; 10. Housing; 11. Filter; 12. Liquid supply pipe; 13. Spinning flow channel; 14. Screw; 15. Drive screw; 16. Speed ​​increaser; 17. Coupling; 18. Auxiliary motor; 19. Nozzle. Detailed Implementation

[0038] The present invention discloses a high-solids-content, low-viscosity spinning solution stabilization device, comprising a method for preparing a high-solids-content organic polymer spinning solution and a high-inorganic-component-content spinning solution, a spinning solution compounding device, a filter, and a shear stabilization device.

[0039] A method for preparing a high-solids-content organic spinning solution: Low molecular weight polymers and solvents are added to a spinning solution compounding device through a secondary inlet. High molecular weight polymers are continuously and slowly released into the solution through a main inlet, a stirring paddle, and a branch-shaped hollow flow channel, undergoing a series of complex physicochemical reactions such as swelling, unlimited swelling and dissolution, substitution, addition, and esterification to obtain a high-solids-content, low-viscosity polymer solution. The solids content of the organic spinning solution is 20–60 wt%, and the viscosity is 300–1000 mPa·s.

[0040] Method for preparing spinning solution with high inorganic component content: Metal alkoxides are added to the spinning solution compounding device through the auxiliary inlet. Water-alcohol mixture, acid, etc. are slowly released into the solution through the main inlet, stirring paddle, and branch-shaped hollow flow channel to carry out a series of complex physicochemical reactions such as hydrolysis and condensation to obtain a solution with high inorganic component content. The solid content of the inorganic spinning solution is 40-70 wt%, and the viscosity is 20-600 mPa·s.

[0041] In practice, the above-mentioned spinning solution compounding process takes place in the spinning solution compounding device. The shearing enhancement effect between the diamond baffle and the stirring paddle in the spinning solution compounding device is used to make the spinning raw materials collide fully and achieve uniform dispersion.

[0042] In practice, the spinning solution prepared above is filtered to remove the bubbles generated during the stirring process, ensuring that the solution entering the flow channel is uniform, stable and bubble-free; then the spinning solution enters the shear stabilization device, where the shearing action of the screw in the spinning flow channel is used to keep the spinning solution in a uniform and stable state.

[0043] In specific implementation, the physicochemical reaction conditions in the above-mentioned methods for preparing high solid content organic polymer spinning solutions and high inorganic component content spinning solutions are as follows: stirring is carried out under constant temperature conditions, wherein the constant temperature conditions are 20-100℃, the stirring conditions are 100-1000rpm, and the reaction time is 2-14h.

[0044] In specific implementation, the spinning solution compounding device mainly consists of a main inlet 1, a secondary inlet 2, a main motor 3, a transmission rod 4, a speed increaser 5, a stirring paddle 6, a rhomboid baffle 9, and a housing 10; the stirring paddle 6 is provided with a branch-shaped hollow flow channel 7; the main inlet 1, the stirring paddle 6, and the branch-shaped hollow flow channel 7 are interconnected to provide spinning solution; the main motor 3, the transmission rod 4, and the speed increaser 5 are interconnected to provide stirring power, and the stirring paddle 6 and the rhomboid baffle 9 are placed at intervals.

[0045] In practice, the outlet of the spinning solution compounding device is connected to the filter 11 and the supply pipe 12 to supply the spinning solution to the shear stabilization device.

[0046] In practice, the shear stabilization device mainly consists of a spinning channel 13, a screw 14, a drive screw 15, a speed increaser 16, a coupling 17, an auxiliary motor 18, and a nozzle 19.

[0047] For the preparation of high-solids-content, low-viscosity organic polymer spinning solutions, the high molecular weight polymers selected from the following combinations are used in the main inlet 1, the stirring paddle 6, and the branch-shaped hollow flow channel 7: polyethylene, polystyrene, polypropylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, polyurethane, polybutylene butyrate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyethersulfone, ethylene-vinyl acetate copolymer, and polysulfone.

[0048] In specific implementation, for the preparation of high solids content and low viscosity organic polymer spinning solution, the spinning raw material in the main inlet 1, stirring paddle 6, and branch-shaped hollow flow channel 7 is a high molecular weight polymer with a molecular weight of 350,000 to 1,000,000.

[0049] In specific implementation, for spinning solutions with high inorganic component content, the solvents such as water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, chloroplatinic acid hexahydrate, acetone, benzene, toluene, xylene, diethyl ether, acetylacetone, acetone, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, benzene, toluene, xylene, and styrene are selected from one or more combinations thereof; the acid is selected from one or more combinations thereof, oxalic acid, acetic acid, and citric acid.

[0050] In specific implementation, for the preparation of high-solids-content, low-viscosity organic polymer spinning solutions, the low molecular weight polymer in the secondary inlet 2 is selected from one or more combinations of polyethylene, polystyrene, polypropylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, polyurethane, polybutylene butyrate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyethersulfone, ethylene-vinyl acetate copolymer, and polysulfone; the solvent is selected from water, N,N-dimethylformamide, N,N-dimethylformamide, etc. Acetamide, dimethyl sulfoxide, N-methylpyrrolidone, acetone, acetylacetone, benzene, toluene, xylene, styrene, pentane, methane, octane, cyclohexane, cyclohexanone, toluenecyclohexanone, methyl ethyl ketone, chlorobenzene, dichlorobenzene, dichloromethane, trichloroethylene, carbon tetrachloride, tetrachloroethane, carbon tetrachloride, chloroform, formic acid, phosphoric acid, glacial acetic acid, hydrochloric acid, ethyl acetate, amyl acetate, tetrahydrofuran, methanol, ethanol, isopropanol, ethylene glycol, diethyl ether, and propylene oxide are one or more combinations thereof.

[0051] In specific implementation, for the preparation of high solids content and low viscosity organic polymer spinning solution, the spinning raw material in the auxiliary inlet 2 includes low molecular weight polymers with a molecular weight range of 50,000 to 300,000.

[0052] In specific implementation, for spinning solutions with high inorganic component content, the inorganic alkoxide at the secondary inlet 2 is selected from one or more combinations of tetraethyl orthosilicate, methyl silicate, hexachlorosilane, methyltriethoxysilane, tetramethoxysilane, 3-aminopropyltriethoxysilane, methyltrimethoxysilane, dimethoxydimethylsilane, trimethylchlorosilane, dimethoxymethane, aluminum isopropoxide, aluminum sec-butoxide, aluminum tert-butoxide, aluminum chloride hexahydrate, aluminum nitrate, aluminum chloride, zirconium acetylacetonate, zirconium acetate, zirconium n-propoxide, zirconium n-butoxide, zirconium nitrate pentahydrate, zirconium oxynitrate hydrate, titanium tetramethanol, zirconium oxychloride, basic zirconium carbonate, tetrabutyl titanate, titanium trichloride, tetraethyl titanate, and titanium tetraethanol.

[0053] In practice, the main inlet 1, the stirring paddle 6, and the branch-shaped hollow flow channel 7 in the spinning solution compounding device are connected, and the material is one of steel, copper, carbon, or their alloys.

[0054] In practical implementation, the branch-shaped hollow flow channel 7 facilitates the slow release of spinning solution from the flow channel, avoiding the aggregation and coagulation phenomenon formed by rapid reaction. Moreover, its flow channel end is narrow and its inlet is wide, ensuring smooth liquid outflow without backflow. The number of branch-shaped structures in its spinning solution compounding device is 7 to 15.

[0055] In specific implementation, the diamond-shaped baffle 9 is made of steel, copper, carbon, or their alloys.

[0056] In practice, the stirring paddle 6 and the rhomboid baffle 9 are placed opposite each other to synergistically enhance the shearing effect on the spinning solution.

[0057] In specific implementation, the filter 11 is made of one of the following materials: steel, copper, aluminum, iron, copper alloy, or aluminum alloy. Its core filter membrane material is one of the following: polytetrafluoroethylene filter membrane, nylon filter membrane, polyvinylidene fluoride filter membrane, regenerated cellulose filter membrane, polyethersulfone filter membrane, or mixed cellulose ester filter membrane.

[0058] In practice, a screw shearing device is installed in the spinning channel 13. The shearing action of the screw 14 is used to regulate the dispersion uniformity and flowability of the spinning solution.

[0059] In practice, the screw 14, drive screw 15, speed increaser 16, coupling 17, and auxiliary motor 18 in the spinning channel 13 are connected to ensure the internal pressure rotation of the screw, thereby smoothly supplying the spinning solution to the spinning nozzle.

[0060] In specific implementation, the screw 14 is made of at least one of the following materials: 40Cr, 38CrMoAl, 34CrAlNi, 31CrMo12, EFZD, DC53, SKH-9, SKH-51, SKH-55, SKH-59, or W18Cr4V.

[0061] In practice, the speed of the auxiliary motor 18 is 200 to 700 rpm.

[0062] In practice, the number of spinning nozzles 19 is 30 to 120.

[0063] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Any preparation methods, materials, structures, or compositional ratios not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0064] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0065] Example 1

[0066] This embodiment describes a method for stabilizing a high-solids-content, low-viscosity spinning solution, with the following specific steps:

[0067] Step 1: Take 10.5 kg of polyvinylidene fluoride (PVDF-30) with a molecular weight of 300,000, 4.5 kg of polyvinylidene fluoride (PVDF-70) with a molecular weight of 700,000, and 35 kg of N,N-dimethylformamide. PVDF-70 is slowly introduced into the spinning solution compounding device through the main inlet, the agitator, and the branch-shaped hollow flow channel. PVDF-30 and N,N-dimethylformamide are added into the spinning solution compounding device through the auxiliary inlet for compounding and mixing to obtain a transparent and spinnable organic solution.

[0068] Step 2: During the preparation of the above organic solution, the conditions for compounding in the spinning solution compounding device are as follows: stirring is carried out under constant temperature conditions, namely: 35℃, stirring conditions are 700rpm, and reaction time is 12h.

[0069] Step 3: Use a filter to remove the air bubbles generated by vigorous stirring from the solution obtained above;

[0070] Step 4: The spinning solution enters the shear stabilization device. Utilizing the internal pressure rotation of the screw in the spinning channel, with a screw speed of 300 rpm, a uniform and stable high-solids-content, low-viscosity organic polymer spinning solution with a solid content of 30 wt% and a viscosity of 1000 mPa·s is finally obtained.

[0071] Example 2

[0072] This embodiment describes a method for stabilizing a high-solids-content, low-viscosity spinning solution, with the following specific steps:

[0073] Step 1: Take 7.2 kg of polyacrylonitrile (PAN-15) with a molecular weight of 150,000, 4.8 kg of polyvinylidene fluoride (PAN-100) with a molecular weight of 1 million, and 48 kg of N,N-dimethylacetamide. PAN-100 is slowly introduced into the spinning solution compounding device through the main inlet, the agitator, and the branch-shaped hollow flow channel. PAN-15 and N,N-dimethylacetamide are added into the spinning solution compounding device through the auxiliary inlet for compounding and mixing to obtain a transparent and spinnable organic solution.

[0074] Step 2: During the preparation of the above organic solution, the conditions for compounding in the spinning solution compounding device are as follows: stirring is carried out under constant temperature conditions, namely: 20℃, stirring conditions are 900rpm, and reaction time is 8h.

[0075] Step 3: Use a filter to remove the air bubbles generated by vigorous stirring from the solution obtained above;

[0076] Step 4: The spinning solution enters the shear stabilization device. Utilizing the internal pressure rotation of the screw in the spinning channel, with a screw speed of 600 rpm, a uniform and stable high-solids-content, low-viscosity organic polymer spinning solution with a solid content of 20 wt% and a viscosity of 300 mPa·s is finally obtained.

[0077] Example 3

[0078] This embodiment describes a method for stabilizing a high-solids-content, low-viscosity spinning solution, with the following specific steps:

[0079] Step 1: Take 27 kg of polystyrene (PS-5) with a molecular weight of 50,000, 15 kg of polyurethane (PS-35) with a molecular weight of 350,000, and 28 kg of dimethyl sulfoxide. PS-35 is slowly introduced into the spinning solution compounding device through the main inlet, the agitator, and the branch-shaped hollow flow channel. PS-5 and dimethyl sulfoxide are added into the spinning solution compounding device through the auxiliary inlet and mixed to obtain a transparent and spinnable organic solution.

[0080] Step 2: During the preparation of the above organic solution, the conditions for compounding in the spinning solution compounding device are as follows: stirring is carried out under constant temperature conditions, namely: 25℃, stirring conditions are 500rpm, and reaction time is 10h.

[0081] Step 3: Use a filter to remove the air bubbles generated by vigorous stirring from the solution obtained above;

[0082] Step 4: The spinning solution enters the shear stabilization device. Utilizing the internal pressure rotation of the screw in the spinning channel, with a screw speed of 400 rpm, a uniform and stable high-solids-content, low-viscosity organic polymer spinning solution with a solid content of 60 wt% and a viscosity of 500 mPa·s is finally obtained.

[0083] Example 4

[0084] This embodiment describes a method for stabilizing a high-solids-content, low-viscosity spinning solution, with the following specific steps:

[0085] Step 1: Take 15 kg of aluminum sec-butoxide, 35.6 kg of sec-butanol, and 2.4 kg of acetylacetone respectively. The sec-butanol is slowly introduced into the spinning solution compounding device through the main inlet, the agitator, and the branch-shaped hollow flow channel. The aluminum sec-butoxide and acetylacetone are added into the spinning solution compounding device through the auxiliary inlet to undergo a coordination reaction. Then, a mixture of 0.5 kg of water, 0.1 kg of hydrochloric acid, and 0.1 kg of chloroplatinic acid hexahydrate is slowly added dropwise through the main inlet and the branch-shaped hollow flow channel to prevent local over-hydrolysis, thus obtaining a transparent and spinnable inorganic solution.

[0086] Step 2: In the above inorganic solution compounding process, the conditions for the coordination reaction in the spinning solution compounding device are: stirring under constant temperature conditions, namely: 25℃, stirring condition: 500rpm, and reaction time: 2h; the conditions for the hydrolysis and polycondensation reaction in the spinning solution compounding device are: stirring under constant temperature conditions, namely: 60℃, stirring condition: 1000rpm, and reaction time: 2h.

[0087] Step 3: Use a filter to remove the air bubbles generated by vigorous stirring from the solution obtained above;

[0088] Step 4: The spinning solution enters the shear stabilization device. Utilizing the internal pressure rotation of the screw in the spinning channel, with a screw speed of 700 rpm, a uniform and stable spinning solution with a high inorganic component content of 30 wt% and a viscosity of 20 mPa·s is finally obtained.

[0089] Example 5

[0090] This embodiment describes a method for stabilizing a high-solids-content, low-viscosity spinning solution, with the following specific steps:

[0091] Step 1: Take 35.2 kg of zirconium propoxide, 13.7 kg of acetic acid and 1.4 kg of water respectively. Acetic acid and water are introduced into the spinning solution compounding device through the main inlet, the agitator and the branch-shaped hollow flow channel. They are added drop by drop to prevent local over-hydrolysis. Zirconium propoxide is added into the spinning solution compounding device through the auxiliary inlet to undergo hydrolysis and condensation reaction to obtain a transparent and spinnable inorganic solution.

[0092] Step 2: During the inorganic solution compounding process described above, the reaction conditions in the spinning solution compounding device are as follows: stirring is carried out under constant temperature conditions, namely: 100℃, stirring conditions are 100rpm, and reaction time is 6h.

[0093] Step 3: Use a filter to remove the air bubbles generated by vigorous stirring from the solution obtained above;

[0094] Step 4: The spinning solution enters the shear stabilization device. Utilizing the internal pressure rotation of the screw in the spinning channel, with a screw speed of 200 rpm, a uniform and stable spinning solution with a high inorganic component content of 70 wt% solids and a viscosity of 600 mPa·s is finally obtained.

[0095] Example 6

[0096] This embodiment describes a device and method for stabilizing a high-solids-content, low-viscosity spinning solution. The specific steps are as follows:

[0097] Step 1: Take 7.2 kg of aluminum chloride, 40 kg of water, and 7.3 kg of tetraethyl silicate and add them to the spinning solution compounding device through the auxiliary inlet. Then, take 15.3 kg of aluminum isopropoxide and 0.1 kg of oxalic acid and slowly add them drop by drop through the main inlet, the agitator, and the branch-shaped hollow channel to obtain a transparent precursor solution. Then, add 3 kg of polyvinyl alcohol to the above solution through the main inlet and the branch-shaped hollow channel for slow compounding to obtain a spinnable inorganic solution.

[0098] Step 2: In the above inorganic solution compounding process, the conditions for hydrolysis and polycondensation reactions in the spinning solution compounding device are as follows: stirring is carried out under constant temperature conditions, namely: 25℃, stirring conditions are 200rpm, and the reaction time is 10h; the conditions for compounding reactions carried out in the spinning solution compounding device are as follows: stirring is carried out under constant temperature conditions, namely: 25℃, stirring conditions are 300rpm, and the reaction time is 4h.

[0099] Step 3: Use a filter to remove the air bubbles generated by vigorous stirring from the solution obtained above;

[0100] Step 4: The spinning solution enters the shear stabilization device. Utilizing the reverse internal pressure rotation of the screw in the spinning channel, with a screw speed of 200 rpm, a uniform and stable spinning solution with a high inorganic component content of 40 wt% solids and a viscosity of 400 mPa·s is finally obtained.

[0101] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a high-solids-content, low-viscosity spinning solution, characterized in that, This is achieved using a high-solids-content, low-viscosity spinning solution preparation device, which includes: A spinning solution compounding device includes a spinning solution compounding tank and the following components disposed on the spinning solution compounding tank: a main inlet (1), a hollow stirring rod, a secondary inlet (2), an outlet, a stirring paddle (6) disposed on the hollow stirring rod, and a main motor (3) for driving the stirring paddle (6). The stirring paddle (6) is provided with a branch-shaped hollow flow channel (7). The main inlet (1) is located at the end of the hollow stirring rod. The branch-shaped hollow flow channel (7) is connected to the hollow stirring rod. A rhomboid baffle (9) is provided on the inner wall of the spinning solution compounding tank. The plane of the rhomboid baffle (9) is parallel to the axial direction of the hollow stirring rod. The rhomboid baffle (9) and the stirring paddle (6) are distributed at intervals in the axial direction of the hollow stirring rod. The shear stabilization device includes a spinning channel (13) connected to the liquid outlet, a shear screw (14) disposed in the spinning channel (13), an auxiliary motor (18) for driving the shear screw (14), and a nozzle (19) disposed at the bottom of the spinning channel (13). The hollow stirring rod is provided with multiple stirring blades (6) along the axial direction, wherein the lower surface of the lowest stirring blade (6) is a downwardly convex arc-shaped structure (8). The branch-shaped hollow flow channel (7) includes a main flow channel that is connected to the interior of the hollow stirring rod and multiple branch flow channels that are connected to the main flow channel respectively. The branch flow channels are connected to the spinning solution compounding tank. The spinning solution compounding device also includes a filter (11) disposed on the spinning solution compounding tank, and the filter (11) is connected to the spinning channel (13) through a liquid supply pipe (12); The shear stabilization device also includes a speed increaser (16), the auxiliary motor (18) is connected to the speed increaser (16) via a coupling (17), and the speed increaser (16) is connected to the shear screw (14) via a drive screw (15). The preparation method of the high solids content, low viscosity spinning solution includes the following steps: By compounding polymer solutions with different molecular weights at equal viscosities, a high-low molecular weight bimodal distribution spinning solution formulation is designed to obtain a high solid content and low viscosity organic spinning solution. Specifically, the high molecular weight polymer is introduced into the stirring paddle (6) and the branch-shaped hollow flow channel (7) through the main inlet (1), and finally into the spinning solution compounding device. The low molecular weight polymer and solvent are introduced into the spinning solution compounding device through the auxiliary inlet (2) to carry out physicochemical reactions. After passing through the spinning solution compounding device and the shear stabilization device, a high solid content and low viscosity organic spinning solution is obtained. The solid content in the organic spinning solution is 20~60wt%, and the viscosity is 300~1000mPa·s. The high molecular weight polymer has a molecular weight of 350,000 to 1,000,000, and the low molecular weight polymer has a molecular weight of 500,000 to 300,000. By adjusting the amount and rate of water-alcohol mixture addition, the hydrolysis and polycondensation reaction rate of metal alkoxides can be precisely controlled to obtain inorganic spinning solution with high inorganic component content. Specifically, the water-alcohol mixture and acid are introduced into the stirring paddle (6) and the branch-shaped hollow channel (7) through the main inlet (1), and the metal alkoxide is introduced into the spinning solution compounding device through the auxiliary inlet (2) for physicochemical reaction. After passing through the spinning solution compounding device and the shear stabilization device, a solution with high inorganic component content is obtained. The solid content in the inorganic spinning solution is 40~70wt%, and the viscosity is 20~600mPa·s. The conditions for the physicochemical reaction are as follows: stirring is carried out under constant temperature conditions, namely 20~100℃, stirring conditions are 100~1000rpm, and reaction time is 2~14h.

2. The method for preparing a high-solids-content, low-viscosity spinning solution according to claim 1, characterized in that, The speed increaser (16) is a variable speed gear speed increaser; The shearing action of the screw (14) controls the dispersion uniformity and fluidity of the spinning solution, and ensures the internal pressure rotation of the screw (14), thereby smoothly supplying the spinning solution to the nozzle (19).

3. The method for preparing a high-solids-content, low-viscosity spinning solution according to claim 1, characterized in that, For the preparation of high-solids-content, low-viscosity organic polymer spinning solutions, the high molecular weight polymer added to the main inlet (1) is selected from one or more combinations of polyethylene, polystyrene, polypropylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, polyurethane, polybutylene butyrate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyethersulfone, ethylene-vinyl acetate copolymer, and polysulfone. For the preparation of spinning solution with high inorganic component content, the solvent in the water-alcohol mixture added to the main inlet (1) is selected from one or more combinations of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butanol, 1-pentanol, 2-pentanol, and 3-pentanol; the acid is selected from one or more combinations of oxalic acid, acetic acid, and citric acid.

4. The method for preparing a high-solids-content, low-viscosity spinning solution according to claim 1, characterized in that, For the preparation of high solids content and low viscosity organic polymer spinning solution, the low molecular weight polymer in the secondary inlet (2) is selected from one or more combinations of polyethylene, polystyrene, polypropylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, polyurethane, polybutylene butyrate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyethersulfone, ethylene-vinyl acetate copolymer, and polysulfone; the solvent is selected from one or more combinations of water, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, acetone, acetylacetone, benzene, toluene, xylene, styrene, pentane, methane, octane, cyclohexane, cyclohexanone, methyl ethyl ketone, chlorobenzene, dichlorobenzene, dichloromethane, trichloroethylene, carbon tetrachloride, tetrachloroethane, carbon tetrachloride, chloroform, formic acid, phosphoric acid, glacial acetic acid, hydrochloric acid, ethyl acetate, amyl acetate, tetrahydrofuran, methanol, ethanol, isopropanol, ethylene glycol, diethyl ether, and propylene oxide. For spinning solutions with high inorganic component content, the metal alkoxide is selected from one or more combinations of aluminum isopropoxide, aluminum sec-butoxide, aluminum tert-butoxide, zirconium n-propoxide, zirconium n-butoxide, titanium tetramethanol, tetrabutyl titanate, and titanium tetraethanol.

5. The method for preparing a high-solids-content, low-viscosity spinning solution according to claim 1, characterized in that, The speed of the speed increaser (16) is 200~700 rpm.

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