Electrospinning apparatus and method for batch production of multi-stranded nanofiber yarns

Abstract

The application discloses a static spinning device and method for batch preparation of multi-strand nanofiber yarns, and the spinning device comprises an injection unit, a power supply unit, a collection unit and a twisting unit. According to the application, a plurality of interval distributed needle heads are connected to each injection pipeline, so that a plurality of mutually separated nanofiber filaments can be formed in the same electric field, and subsequent processing is facilitated. On the other hand, the jet of spinning solution emitted by the needle heads can simultaneously implement the processes of stretching into filaments and twisting into yarns by distributing the vortex emitted by the gas guide pipe around the plurality of needle heads of each group, and the multi-strand nanofiber yarns can be automatically folded and collected in combination with a buncher, so that the operation is greatly simplified, the spinning time is shortened, the yield is effectively improved, and batch production is realized.

Description

Technical Field

[0001] This invention belongs to the field of spinning technology, specifically relating to an electrospinning device for batch preparation of multi-strand nanofiber yarns, and also to a method for batch preparation of multi-strand nanofiber yarns. Background Technology

[0002] Nanofibers have wide applications in filtration, personal protective equipment, sensors, catalysts, military, and aerospace. Among nanofiber preparation methods, electrospinning is currently the most commonly used method for preparing nanofibers due to its simplicity and the advantages of producing fibers that are lightweight, highly permeable, and have a large specific surface area.

[0003] Traditional nanofiber electrospinning devices mainly include a syringe, a high-voltage power supply, and a collector. The syringe, which contains spinning solution, ejects a jet of water. The jet is stretched and refined into nanofibers in a high-voltage electric field, and finally, the collector winds up the nanofibers.

[0004] However, in actual preparation, traditional nanofiber electrospinning devices struggle to produce separate nanofiber filaments or short fibers, hindering further processing. Moreover, the directly spun nanofiber filaments exhibit poor mechanical properties, failing to meet application requirements. To obtain nanofiber yarn products that meet mechanical performance requirements, traditional spinning devices need to be combined with twisting equipment. The twisting equipment twists the nanofibers to form yarn, improving mechanical properties. The entire process involves winding, transporting, unwinding, and twisting of the nanofiber filaments, which is cumbersome. Furthermore, there is a high probability of filament breakage during winding and unwinding, requiring time-consuming re-splicing, impacting spinning efficiency, and reducing production output. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an improved electrospinning device for mass production of multi-strand nanofiber yarns.

[0006] In addition, the present invention also provides a method for batch preparation of multi-strand nanofiber yarns.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0008] An electrospinning apparatus for mass production of multi-strand nanofiber yarns includes: an injection unit comprising a syringe containing spinning solution and having injection channels; a power supply unit comprising a high-voltage power supply; a collection unit comprising a guide roller and a winding cylinder, wherein multiple injection channels are spaced apart; the injection unit further comprises multiple needle assemblies that are connected one-to-one with the ends of the multiple injection channels, wherein each needle assembly comprises multiple needles connected to a corresponding injection channel; the electrospinning apparatus further comprises a twisting unit comprising an air pump and a syringe connected to the ends of the multiple needle assemblies. The system includes multiple air guide tubes, where an air pump creates a vortex extending along the injection direction between the corresponding multiple needles through each air guide tube; a high-voltage power supply is connected to each needle and generates an electric field to drive the jet ejected from each needle to form a single nanofiber filament, and multiple nanofiber filaments are synchronously twisted through the same vortex to form a single strand of yarn; the collection unit includes a bundler disposed between the yarn guide roller and the injection unit, and a bundler channel that gradually narrows along the injection direction is formed on the bundler. After the multiple strands of yarn are gathered through the bundler channel, they are wound onto the winding drum by the yarn guide roller.

[0009] Preferably, the syringe includes a body having a spinning solution reservoir, a piston inserted into the reservoir, and a power pump for driving the piston to reciprocate within the reservoir. Multiple injection channels are connected to the reservoir and inject spinning solution synchronously as the piston advances. This achieves simultaneous jet ejection from multiple needle assemblies.

[0010] Specifically, each injection tube extends horizontally outward from one end of the device body; the power pump is located below the device body and drives the piston to reciprocate horizontally within the liquid storage chamber.

[0011] Preferably, the multiple needles in each needle assembly are arranged in a circumferential array, and in the orthographic projection of the injection direction, the centers of the ring, vortex, and injection channel formed by the lines connecting the multiple needles coincide. This ensures that the multiple nanofiber filaments in the same group are twisted uniformly, which is beneficial for improving the mechanical properties of the nanofiber yarn.

[0012] Specifically, each needle is cylindrical and has a diameter of 0.3 to 2 mm.

[0013] Preferably, each air tube is inserted into the corresponding injection tubing and extends along the length of the injection tubing.

[0014] Specifically, each air guide tube forms an air outlet on the end face of the corresponding injection tube, and multiple needles are distributed around the outer periphery of the air outlet. Here, by occupying the internal space of the injection tube, the spinning solution can be ensured to be dispersed within the injection tube and the area corresponding to each needle, thus ensuring the hydraulic pressure of the spinning solution and improving the supply speed and stability of the spinning solution.

[0015] Preferably, in the orthographic projection of the injection direction, the inlet of the bundled channel covers multiple injection channels; and / or, the bundled channel is trumpet-shaped, and the cone angle of the bundled channel is set to 60° to 150°. This facilitates the maximum bundling and drying of multi-strand nanofiber yarns by the bundled channel, improving spinning efficiency.

[0016] Furthermore, the collection unit also includes a transfer roller disposed between the bundler and the winding drum and capable of rotating around its own centerline. The extension direction of the transfer roller is perpendicular to the injection direction, and under the rotation of the transfer roller, the multi-strand yarn is tightened by the transfer roller and transferred to the guide roller. Here, the tension of the multi-strand yarn is increased, which facilitates the transfer and collection.

[0017] Another technical solution of the present invention is an electrospinning method for batch preparation of multi-strand nanofiber yarns, which uses the above-mentioned electrospinning apparatus and includes the following steps:

[0018] S1. The syringe supplies spinning solution to the corresponding needle assembly through each injection tube, and each needle ejects a jet. Under the action of the electric field, the jet ejected by each needle forms a single nanofiber filament, and under the action of the same eddy current, multiple nanofiber filaments are simultaneously twisted to form a single strand of yarn.

[0019] S2. After the multi-strand yarns are passed through the bundling channel and gathered together, they are guided by the yarn guide rollers and wound onto the winding drum to complete the continuous batch preparation of multi-strand nanofiber yarns.

[0020] Due to the implementation of the above technical solutions, the present invention has the following advantages compared with the prior art:

[0021] Existing nanofiber electrospinning devices cannot spin nanofibers that meet mechanical performance requirements, and require multiple processes to obtain qualified nanofiber yarn products, resulting in cumbersome operation, long time consumption, and low output. The electrospinning device of this invention cleverly solves the various shortcomings of existing structures through its overall design. This device, under the action of the same electric field, ejects jets from multiple needles in each group to form multiple nanofiber filaments. Under the action of the same vortex, the multiple nanofiber filaments are simultaneously twisted to form a single nanofiber yarn. Combined with the coordination of a bundler, yarn guide roller, and winding cylinder, the multiple nanofiber yarns are gathered, transported, and collected. Therefore, compared with the existing structure, this invention, on the one hand, achieves the formation of multiple separate nanofiber filaments in the same electric field by connecting multiple spaced needles to each injection channel, which facilitates subsequent processing; on the other hand, by distributing the multiple needles in each group around the vortex ejected from the air guide tube, the spinning liquid jets ejected by the needles can simultaneously carry out the processes of stretching into filaments and twisting into yarn. At the same time, combined with the bundler, the multiple nanofiber yarns can be automatically gathered and collected, which greatly simplifies the operation, shortens the spinning time, effectively increases the output, and thus realizes mass production. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the electrospinning device for mass production of multi-strand nanofiber yarns according to the present invention.

[0023] Figure 2 for Figure 1 A magnified schematic diagram of the structure of a single injection tubing and needle assembly;

[0024] Figure 3 for Figure 1 A magnified schematic diagram of a portion of the structure of a single-strand nanofiber yarn;

[0025] Wherein: 1, injection unit; 10, syringe; g, injection tubing; 100, device body; q, reservoir; 101, piston; 102, power pump; 11, needle assembly; 110, needle;

[0026] 2. Power supply unit; 20. High-voltage power supply;

[0027] 3. Twisting unit; 30. Air pump; 31. Air guide tube; w. Vortex;

[0028] 4. Collection unit; 40. Bundler; t. Bundling channel; 41. Transfer roller; 42. Guide roller; 43. Winding cylinder. Detailed Implementation

[0029] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0030] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0033] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0034] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0035] like Figures 1 to 3 As shown, the electrospinning device for mass production of multi-strand nanofiber yarns in this embodiment includes an injection unit 1, a power supply unit 2, a twisting unit 3, and a collection unit 4.

[0036] Specifically, the injection unit 1 includes a syringe 10 and a needle assembly 11, wherein the syringe 10 is used to hold the spinning solution and has multiple injection tubes g, and the needle assembly 11 has multiple needles and is connected to the ends of the multiple injection tubes g.

[0037] In some specific embodiments, the number of injection channels g can be set to 2 to 20; the syringe 10 has a device body 100 with a spinning solution reservoir q, a piston 101 inserted in the reservoir q, and a power pump 102 that drives the piston 101 to reciprocate within the reservoir q, wherein multiple injection channels g are connected to the reservoir q and inject spinning solution synchronously as the piston 101 advances. Specifically, each injection channel g extends horizontally outward from one end of the device body 100, and the power pump 102 is located below the device body 100 and drives the piston 101 to reciprocate horizontally within the reservoir q.

[0038] Each needle assembly 11 includes multiple needles 110 connected to the corresponding injection conduit g. The number of needles 110 can be 2 to 10. In this example, there are six needles 110, and the six needles 110 are connected to the end face of the injection conduit g in a circumferential array. Each needle 110 is cylindrical and has a diameter of 0.3 to 2 mm.

[0039] In this example, the power supply unit 2 includes a high-voltage power supply 20, which is connected to each needle 110 via wires and generates an electric field to stretch and refine the jet ejected from each needle 110 into a single nanofiber filament. The output voltage range of the high-voltage power supply 20 is 0–30 kV.

[0040] In this example, the twisting unit 3 includes an air pump 30 and multiple air guide tubes 31 corresponding to multiple needle assemblies 11. The air pump 30 is a standard component. The air pump 30 forms a vortex w extending along the injection direction between the corresponding multiple needles 110 through each air guide tube 31. Multiple nanofibers formed in the same group are synchronously twisted through the same vortex w to form a single strand of yarn. S twist or Z twist can be selected according to actual production needs.

[0041] In some specific embodiments, each air guide tube 31 is inserted into the corresponding injection tube g and extends along the length of the injection tube g; each air guide tube 31 forms an air outlet on the end face of the corresponding injection tube g, and the corresponding six needles 110 are arranged in a circumferential array around the outer periphery of the air outlet. At the same time, in the orthographic projection in the injection direction, the centers of the ring formed by the lines connecting the multiple needles 110, the vortex w, and the injection tube g are aligned.

[0042] In this example, the collecting unit 4 includes a bundler 40, a transfer roller 41, a yarn guide roller 42, and a winding drum 43 arranged in sequence. The bundler 40 has a bundle channel t that gradually narrows along the injection direction. After multiple strands of yarn are gathered together through the bundle channel t, they pass through the transfer roller 41 and the yarn guide roller 42 in sequence, and are finally wound onto the winding drum 43.

[0043] Specifically, the cluster channel t is trumpet-shaped, and the cone angle of the cluster channel t is set to 60° to 150°. According to the specific implementation effect, the effect formed by the cone angle is 80° to 130°. In the orthographic projection of the injection direction, the inlet of the cluster channel t can cover multiple injection channels g.

[0044] In addition, the extension direction of the transfer roller 41 is perpendicular to the injection direction, and under the rotation of the transfer roller 41, multiple strands of yarn are tightened by the transfer roller 41 and transferred to the guide roller 42; there are two guide rollers 42 arranged side by side at intervals; the winding cylinder 43 is a standard part.

[0045] Therefore, the spinning method of this embodiment includes the following steps:

[0046] S1. The syringe 10 supplies spinning solution to the corresponding needle assembly 11 through each injection tube g. Each needle 110 then ejects a jet. Under the action of the electric field, the jet ejected by each needle 110 forms a single nanofiber filament. Under the action of the same eddy current, multiple nanofiber filaments are simultaneously twisted to form a single strand of yarn.

[0047] S2. After the multi-strand yarn is passed through the bundling channel t and gathered together, it is stretched and guided by the transfer roller 41 and the guide roller 42 and wound onto the winding drum 43 to complete the continuous batch preparation of multi-strand nanofiber yarn.

[0048] In summary, this implementation has the following advantages:

[0049] 1. On the one hand, by connecting multiple spaced needles to each injection channel, multiple separate nanofiber filaments are formed in the same electric field, which facilitates subsequent processing. On the other hand, by distributing multiple needles in each group around the vortex ejected from the air guide tube, the spinning liquid jet ejected by the needles can simultaneously carry out the processes of stretching into filaments and twisting into yarn. At the same time, combined with the bundler, multiple strands of nanofiber yarns can be automatically gathered and collected, which greatly simplifies the operation, shortens the spinning time, effectively increases the output, and thus realizes mass production.

[0050] 2. By strategically positioning the needles, vortex, and injection channels, the uniform twisting of multiple nanofiber filaments within the same group is ensured, which helps improve the mechanical properties of the nanofiber yarn.

[0051] 3. By using the air guide tube to occupy the internal space of the injection pipe, it is possible to ensure that the spinning solution is dispersed in the injection pipe and the area corresponding to each needle, thus ensuring the hydraulic pressure of the spinning solution and improving the supply speed and stability of the spinning solution.

[0052] 4. The rotation of the conveyor rollers can achieve the stretching effect of multi-strand yarns, increase the tension of multi-strand yarns, and facilitate transmission and collection.

[0053] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. An electrospinning device for batch production of multi-strand nanofiber yarns, comprising: an injection unit comprising a syringe containing a spinning solution and having injection conduits; a power supply unit comprising a high-voltage power supply; a collection unit comprising a godet, a bobbin, characterized in that: the injection conduits are multiple and are spaced apart; the injection unit further comprises multiple needle assemblies in one-to-one correspondence with the ends of the multiple injection conduits, wherein each of the needle assemblies comprises multiple needles in communication with the corresponding injection conduit; the electrospinning device further comprises a twisting unit, the twisting unit comprising an air pump and multiple air guides in one-to-one correspondence with the multiple needle assemblies, wherein the air pump forms a vortex extending along the injection direction between the corresponding multiple needles through each of the air guides; the high-voltage power supply is in communication with each of the needles and generates an electric field to drive the jet sprayed by each of the needles to form a single nanofiber filament synchronously, and multiple nanofiber filaments are twisted synchronously by the same vortex to form a single yarn; the collection unit comprises a buncher arranged between the godet and the injection unit, the buncher having a bunching channel formed thereon and gradually narrowing along the injection direction, and the multiple yarns are gathered through the bunching channel and then wound on the bobbin by the godet.

2. The electrospinning apparatus for batch production of multi-stranded nanofiber yarns according to claim 1, characterized in that: the syringe comprises a syringe body having a spinning solution storage cavity, a piston inserted in the storage cavity, and a power pump for driving the piston to reciprocate in the storage cavity, wherein the multiple injection conduits are in communication with the storage cavity, and the spinning solution is injected synchronously with the advancement of the piston.

3. The electrospinning apparatus for batch production of multi-stranded nanofiber yarns according to claim 2, characterized in that: Each of the injection conduits extends horizontally outward from one end of the syringe body; the power pump is arranged below the syringe body and drives the piston to reciprocate horizontally in the storage cavity.

4. The electrospinning apparatus for batch production of multi-filament nanofiber yarn according to claim 1, characterized in that: The multiple needles in each of the needle assemblies are arranged in a circumferential array, and in the orthogonal projection of the injection direction, the centers of the multiple needles, the vortex, and the injection conduit are arranged coincidentally.

5. The electrospinning apparatus for batch production of multi-stranded nanofiber yarn according to claim 1 or 4, characterized in that: Each of the needles is cylindrical, and the diameter of each of the needles is 0.3-2 mm.

6. The electrospinning apparatus for batch production of multi-filament nanofiber yarn according to claim 1, characterized in that: Each of the air guides is inserted in the corresponding injection conduit and extends along the length direction of the injection conduit.

7. The electrospinning apparatus for batch production of multi-stranded nanofiber yarns according to claim 6, characterized in that: Each of the air guides forms an air outlet on the end face of the corresponding injection conduit, and the corresponding multiple needles are arranged around the outer periphery of the air outlet.

8. The electrospinning apparatus for batch production of multi-filament nanofiber yarn according to claim 1, characterized in that: In the orthogonal projection of the injection direction, the inlet of the bunching channel covers multiple injection conduits; and / or, the bunching channel is trumpet-shaped, and the taper angle of the bunching channel is arranged to be 60-150°.

9. The electrospinning apparatus for batch production of multi-filament nanofiber yarn according to claim 1, characterized in that: The collection unit further comprises a transfer roller arranged between the buncher and the bobbin and capable of rotating around its center line, wherein the extension direction of the transfer roller is perpendicular to the injection direction, and under the rotation of the transfer roller, the multiple yarns are tightened and transferred to the godet.

10. An electrospinning process for batch production of multi-stranded nanofiber yarns, characterized by: It adopts the electrospinning device according to any one of claims 1-9, and comprises the following steps: S1, supplying the spinning solution to the corresponding needle assembly through each of the injection pipes by the injector, each of the needles spouting a jet flow, wherein under the action of the same electric field, the jet flow spouted by each of the needles forms a single nanofiber yarn, and under the action of the same vortex, a plurality of nanofiber yarns are twisted synchronously to form a single yarn; S2, after the formed plurality of yarns pass through the bundling channel and are gathered, the yarns are guided by the guide roller and are wound on the bobbin, completing the continuous batch preparation of the plurality of nanofiber yarns.

Images