An electrostatic spinning nozzle

Abstract

This invention provides an electrospinning nozzle, belonging to the field of nanofiber preparation technology. It includes a multi-channel distribution structure, a vertical holding structure, and peripheral flow-guiding holding blades. The vertical holding structure and peripheral flow-guiding holding blades are located on the output side of the multi-channel distribution structure, with several peripheral flow-guiding holding blades arranged around the vertical holding structure. The multi-channel distribution structure includes a straight tube body with several inclined flow-guiding channels inside. The vertical holding structure includes a mounting post and holding plates, with the holding plates arranged around the mounting post. The peripheral flow-guiding holding blades have outwardly convex arc-shaped sides, and the bottom of the front surface of each blade is an inverted triangle with a flow-guiding slit at its axial position. This invention has the advantages of avoiding clogging, guiding flow, holding spinning solution droplets for a longer period, increasing spinning output, and reducing energy waste.

Description

Technical Field

[0001] This invention belongs to the field of nanofiber preparation technology, and in particular relates to an electrospinning nozzle. Background Technology

[0002] Electrospinning is a process that uses a polymer solution or melt to form a jet stretching effect under the action of an external high-voltage electrostatic field for continuous spinning. It is one of the most effective technologies for preparing nanofibers.

[0003] Currently, the common methods for increasing production and forming multiple jets in electrospinning technology can be broadly divided into two categories: multi-needle electrospinning and free surface electrospinning. Multi-needle electrospinning technology is generally achieved through the linear arrangement of traditional metal capillary needles, such as the technologies disclosed in patents CN104862788B and WO2007035011. Because of its closed liquid supply method and the fact that the solution is not easily volatile, it can quickly increase production. However, the problems that follow are that the needle inner diameter is small, making it easy to clog, and the electrostatic repulsion (edge ​​effect) between the needles is very serious, resulting in uneven thickness of the fiber web from the middle to both sides. Free-surface electrospinning technology generally utilizes mechanical external force, electromagnetic force, air pressure expansion, and other forces to introduce the entire or partial spinning liquid surface into an electric field. Through the recombination of the free-surface liquid, multiple jets are formed, which is also commonly referred to as needleless electrospinning. For example, patent WO2005024101 discloses the first generation of "nano-spider"; patent CN103484953B discloses a needleless electrospinning device that can continuously produce nanofiber membranes on a large scale, avoiding the disadvantages of traditional needle-based equipment such as uneven electric field, easy clogging of needles, and difficulty in cleaning; CN206680625U discloses a needleless electrospinning device with continuous liquid supply, which improves spinning efficiency. It is evident that, compared to multi-needle electrospinning technology, free-surface electrospinning technology has higher yield and is less prone to clogging. However, its disadvantages include a larger area for applying the spinning emitter voltage, requiring a higher voltage to excite the Taylor cone, resulting in higher energy consumption. Furthermore, since the jet is formed by the recombination of liquid on a free surface, the position and state of the Taylor cone are uncontrollable. The open area on the solution surface is large, and the solvent is easily volatile, making it difficult to control the quality of the final fiber and affecting the consistency of fiber orientation. Summary of the Invention

[0004] The problem to be solved by the present invention is to provide an electrospinning nozzle.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: an electrostatic spinning nozzle, comprising a multi-channel distribution structure, a vertical gripping structure, and peripheral flow-guiding gripping blades. The vertical gripping structure and the peripheral flow-guiding gripping blades are located on the output side of the multi-channel distribution structure, and a plurality of peripheral flow-guiding gripping blades are arranged around the vertical gripping structure. The multi-channel distribution structure includes a straight tube body, with a connecting hole at the center of the inside of the straight tube body. A plurality of inclined flow-guiding channels are evenly arranged around the connecting hole, and a flow-guiding channel is provided between the inclined flow-guiding channels. The vertical gripping structure includes a mounting post and gripping plates. The gripping plates are arranged around the mounting post and are evenly distributed. The peripheral flow-guiding gripping blades are evenly distributed in the middle of the gaps in the gripping plates and are arranged intersecting with the gripping plates. The side of the peripheral flow-guiding gripping blade is an outwardly convex arc shape, and the bottom of the front of the peripheral flow-guiding gripping blade is an inverted triangle. The peripheral flow-guiding gripping blade includes a blade body, and a flow-guiding center slit is provided at the central axial position of the blade body.

[0006] Furthermore, the bottom edge of the straight pipe body is uniformly provided with several sets of inverted trapezoidal slots, the top of the blade body is provided with an inverted trapezoidal connecting block, and the peripheral flow-guiding blade is installed together with the inverted trapezoidal slots of the multi-channel distribution structure through the inverted trapezoidal connecting block.

[0007] Furthermore, each set of inverted trapezoidal slots includes two inverted trapezoidal slots, and a connecting seam is provided between the two inverted trapezoidal slots, the connecting seam being connected to the drainage channel.

[0008] Furthermore, the drainage seam and the connecting seam are correspondingly provided and connected.

[0009] Furthermore, the vertical gripping structure is connected to the connection hole of the multi-channel distribution structure through the central threaded hole on the mounting post.

[0010] Furthermore, the number of the inclined flow channel, the gripping plate, and the peripheral flow gripping blades are the same.

[0011] Furthermore, the inclined flow channel and the gripping piece are respectively provided.

[0012] Furthermore, the upper end of the drainage suture is open and the lower end is closed.

[0013] Furthermore, the flow channel expansion curve formed by the peripheral flow-guiding blades is a curve. ab ,curve ab The straight-line distance between the two ends is the length of the flow channel. Point e is the intersection of the tangent line at point a and the tangent line at point b on curve ab. Construct the line... ae and eb The distances are equal ,point c for Midpoint of the curve ab Arc height With curve ab straight-line distance The ratio is Construction lines ae The angle between the curve and the perpendicular line at point a is the curve. ab outward angle 30°≤ ≤50°.

[0014] By adopting the above technical solution, the present invention has the following beneficial effects:

[0015] (1) The curve arc and curve outward angle of the present invention can make the flow channel formed by the outer flow guiding and holding blade and the vertical holding structure not only able to hold the droplets of spinning solution for a long time and have the effect of stabilizing the droplets; but also, in conjunction with the tip of the outer flow guiding and holding blade, play the role of accumulating charge, which can reduce energy consumption, facilitate the induction and excitation of multiple spinning jets, greatly increase the spinning output, and reduce the waste of electrical energy.

[0016] (2) The multi-channel distribution structure at the input end of the present invention includes a straight tube body. The large inner diameter of the input port can solve the problem of easy clogging of the needle in the traditional capillary needle electrospinning device. It is suitable for electrospinning high-concentration spinning solution systems. The uniformly arranged inclined flow channels in the multi-channel distribution structure enable the spinning solution to be evenly distributed through the channels, while preventing the spinning solution from flowing too fast and thus affecting the final spinning effect.

[0017] (3) The output end of the multi-channel distribution structure of the present invention is provided with a vertical gripping structure. The vertical gripping structure increases the contact area of ​​the entire nozzle interior space with the spinning solution through the gripping plate, thereby increasing the gripping ability of the spinning solution surface.

[0018] (4) In this invention, the peripheral flow-guiding and holding blades are arranged in a cross pattern. The peripheral flow-guiding and holding blades expand outward, while the vertical holding structure is located inside, which increases the interfacial tension between the spinning solution and the nozzle structure. This allows the droplets to be held for a long time, thus stabilizing the droplets and further increasing the holding capacity of the spinning solution surface. In addition to guiding the flow through the capillary effect and directing the spinning solution to the bottom tip position to facilitate the formation of the spinning jet, the flow-guiding slit of the peripheral flow-guiding and holding blades also increases the holding surface. The bottom tip of the peripheral flow-guiding and holding blades can concentrate charges and stimulate multiple spinning jets, thus solving the problems of edge effect caused by the current multi-needle arrangement, high energy consumption of needleless electrospinning technology, and difficulty in controlling fiber quality caused by open liquid supply.

[0019] (5) The present invention is an assembly structure, and each component can be disassembled for easy cleaning. Attached Figure Description

[0020] The present invention will be described in detail below with reference to the accompanying drawings and examples. The advantages and implementation methods of the present invention will become more apparent from this description. The accompanying drawings are for illustrative purposes only and do not constitute any limitation on the present invention. In the accompanying drawings:

[0021] Figure 1 This is a schematic diagram of the structure of the present invention.

[0022] Figure 2 This is an exploded view of the present invention.

[0023] Figure 3 This is a schematic diagram of the multi-channel distribution structure of the present invention.

[0024] Figure 4 This is a top view of the multi-channel distribution structure of the present invention.

[0025] Figure 5 This is a schematic diagram of the structure of the peripheral drainage and holding blade of the present invention.

[0026] Figure 6 For the present invention Figure 5 AA section diagram.

[0027] Figure 7 This is a schematic diagram of the flow channel expansion curve of the peripheral flow-guiding blade of the present invention.

[0028] Figure 8 This is a schematic diagram illustrating the holding effect of the present invention on the spinning solution.

[0029] Figure 9 This is a schematic diagram illustrating the holding effect of a nozzle on the spinning solution in the prior art.

[0030] Figure 10 This is a diagram illustrating the electrospinning effect of the present invention.

[0031] In the picture:

[0032] 1. Multi-channel distribution structure; 2. Vertical gripping structure; 3. Peripheral flow-guiding gripping blades; 11. Straight pipe body; 12. Angled flow-guiding channel; 13. Inverted trapezoidal slot; 14. Connecting hole; 15. Connecting seam; 16. Flow-guiding channel; 21. Central threaded hole; 22. Grip plate; 23. Mounting post; 31. Inverted trapezoidal connecting block; 32. Blade body; 33. Flow-guiding center seam. Detailed Implementation

[0033] like Figures 1 to 6As shown, the present invention provides an electrospinning nozzle, comprising a multi-channel distribution structure 1, a vertical gripping structure 2, and peripheral flow-guiding gripping blades 3. The vertical gripping structure 2 and the peripheral flow-guiding gripping blades 3 are located on the output side of the multi-channel distribution structure 1, and four peripheral flow-guiding gripping blades 3 are arranged around the vertical gripping structure 2.

[0034] The multi-channel distribution structure 1 includes a straight pipe body 11, with a connecting hole 14 at the center of the inside of the straight pipe body 11, and four inclined flow channels 12 evenly arranged around the connecting hole 14, with a flow channel 16 arranged between the inclined flow channels 12; and four sets of inverted trapezoidal slots 13 evenly arranged at the bottom edge of the straight pipe body 11.

[0035] Each set of inverted trapezoidal slots 13 includes two inverted trapezoidal slots 13, and a connecting seam 15 is provided between the two inverted trapezoidal slots 13, which is connected to the drainage channel 16.

[0036] The vertical grip structure 2 includes a mounting post 23 and a gripping piece 22. The vertical grip structure 2 is connected to the connection hole 14 of the multi-channel distribution structure 1 through the central threaded hole 21 on the mounting post 23. The gripping piece 22 is arranged around the mounting post 23. There are four gripping pieces 22, which are evenly distributed and are arranged corresponding to the inclined flow channel 12.

[0037] The peripheral flow-guiding gripping blade 3 includes a blade body 32. An inverted trapezoidal connecting block 31 is provided on the top of the blade body 32. A flow-guiding central slit 33 is provided at the central axial position of the blade body 32. The peripheral flow-guiding gripping blade 3 is installed together with the inverted trapezoidal slot 13 of the multi-channel distribution structure 1 through the inverted trapezoidal connecting block 31. The flow-guiding central slit 33 is correspondingly provided and connected to the connecting slit 15. The peripheral flow-guiding gripping blade 3 is evenly distributed in the middle position of the gap of the gripping piece 22 and is arranged intersecting with the gripping piece 22.

[0038] The outer drainage gripping blade 3 has an outward convex arc shape on its side, and the bottom of the front of the outer drainage gripping blade 3 is an inverted triangle (the side of the outer drainage gripping blade 3 facing outward is the front).

[0039] Among them, the straight pipe body 11 of the multi-channel distribution structure 1 is a wide-diameter straight pipe body with an outer diameter of 12mm, an inner diameter of 8mm, and a length of 5mm at its input end; the gripping plate 22 of the vertical gripping structure 2 has a width of 1mm and a height of 6mm; the width of the drainage center slit 33 of the peripheral drainage gripping blade 3 is 0.2mm.

[0040] like Figure 7 As shown, the cross-sectional curve of the peripheral flow-guiding blade 3 is designed using Bezier curves.

[0041] The flow channel expansion curve formed by the peripheral flow-guiding blade 3 is a curve. ab For ease of calculation, we take the curve. ab The straight-line distance between the two ends is the length of the flow channel. Point e is the intersection of the tangent lines at point a and point b on curve ab, and the geometric relationship includes the construction line. ae and eb The distances are equal, that is .

[0042] Curve curvature design: point c for Midpoint of the curve ab Arc height With curve ab straight-line distance The ratio is .

[0043] Curve outward angle design: According to the theory of quadratic Bézier curves, the construction line... ae Tangent to the curve ab Take the construction line ae The angle between the curve and the perpendicular line at point a is the curve. ab outward angle In this embodiment Set it to 35°.

[0044] like Figure 8 As shown, the nozzle formed by the multi-channel distribution structure 1, the vertical gripping structure 2, and the peripheral flow-guiding gripping blades 3 of this invention reaches its maximum liquid spread in the spinning solution at 36 seconds of operation. As can be seen from the figure, the liquid spreads laterally into the flow-guiding center slit 33 of the peripheral flow-guiding gripping blades 3 (the white block in the figure is the cross-section of the nozzle of this invention, and the areas without cross-sections on both sides are the flow-guiding center slits 33), and longitudinally to the bottom of the peripheral flow-guiding gripping blades 3. The spinning solution only drips or sprays out at 52 seconds of operation, and the liquid shape is symmetrical. It can be seen that the liquid spreads and fills the entire nozzle for 16 seconds before dripping or spraying out, that is, it is held for 16 seconds. This shows that under the combined action of the multi-channel distribution structure 1, the vertical gripping structure 2, and the peripheral flow-guiding gripping blades 3, the contact area between the nozzle and the spinning solution is increased, thereby increasing the holding effect of the liquid.

[0045] like Figure 9 As shown, in the prior art, when the existing nozzle operates for 36 seconds, the liquid on both sides of the spinning solution has already detached from the inner wall of the nozzle and has not spread out, and the bottom of the liquid has already extended out of the nozzle; when operating for 44 seconds, the liquid of the spinning solution drips or sprays out, and the liquid shape is asymmetrical, indicating that the existing nozzle has a poor liquid holding effect, only 8 seconds, and the dripping or spraying liquid shape is poor.

[0046] like Figure 10As shown, by adopting the above-mentioned curve arc and curve outward angle, the flow channel formed by the outer flow guiding and holding blade 3 and the vertical holding structure 2 can not only hold the droplets of spinning solution for a long time and stabilize the droplets, but also, in conjunction with the tip of the outer flow guiding and holding blade 3, play a role in accumulating charge, which can reduce energy consumption, facilitate the induction and excitation of multiple spinning jets, greatly increase the spinning output, and reduce the waste of electrical energy.

[0047] Working principle:

[0048] The multi-channel distribution structure 1 at the input end of this invention includes a straight tube body 11. The large inner diameter of the input port solves the problem of needle clogging in traditional capillary needle-type electrospinning devices, making it suitable for electrospinning high-concentration spinning solution systems. The uniformly arranged inclined flow channels 12 in the multi-channel distribution structure 1 ensure even distribution of the spinning solution through the channels, while preventing excessively high flow rates that could affect the final spinning effect. The output end of the multi-channel distribution structure 1 is equipped with a vertical holding structure 2. The vertical holding structure 2, through holding plates 22, increases the contact area between the entire nozzle interior space and the spinning solution, thereby increasing the holding capacity of the spinning solution surface. In this invention, the peripheral flow-guiding and holding blades 3 and the holding plates 22 are arranged in a cross pattern, which further increases the holding capacity of the spinning solution surface. The flow-guiding slits 33 of the peripheral flow-guiding and holding blades 3 not only guide the spinning solution to the bottom tip position, but also increase the holding liquid surface. The bottom tip of the peripheral flow-guiding and holding blades 3 can play the role of accumulating charges, which can stimulate multiple spinning jets. This solves the problems of easy clogging and low output of needle-type electrospinning, as well as the high energy consumption and difficulty in controlling fiber quality caused by open liquid supply in needleless electrospinning technology.

[0049] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. An electrostatic spinning nozzle, characterized in that: The system includes a multi-channel distribution structure, a vertical gripping structure, and peripheral flow-guiding gripping blades. The vertical gripping structure and peripheral flow-guiding gripping blades are located on the output side of the multi-channel distribution structure, and several peripheral flow-guiding gripping blades are arranged around the vertical gripping structure. The multi-channel distribution structure includes a straight pipe body with a connecting hole at its center. Several inclined flow-guiding channels are evenly arranged around the connecting hole, and flow-guiding channels are provided between the inclined flow-guiding channels. The vertical gripping structure includes a mounting post and gripping plates, which are evenly distributed around the mounting post. The peripheral flow-guiding gripping blades are evenly distributed in the middle of the gaps in the gripping plates and are arranged intersecting with the gripping plates. The sides of the peripheral flow-guiding gripping blades are convex arc-shaped, and the bottom of the front of the peripheral flow-guiding gripping blades is inverted triangular. Each peripheral flow-guiding gripping blade includes a blade body with a flow-guiding center slit at its central axial position. The flow expansion curve formed by the peripheral flow-guiding gripping blades is a curve. ab ,curve ab The straight-line distance between the two ends is the length of the flow channel. Point e is the intersection of the tangent line at point a and the tangent line at point b on curve ab. Construct the line... ae and eb The distances are equal ,point c for Midpoint of the curve ab Arc height With curve ab straight-line distance The ratio is Construction lines ae The angle between the curve and the perpendicular line at point a is the curve. ab outward angle 30°≤ ≤50°.

2. The electrospinning nozzle according to claim 1, characterized in that: The bottom edge of the straight pipe body is evenly provided with several sets of inverted trapezoidal slots, and the top of the blade body is provided with an inverted trapezoidal connecting block. The peripheral flow-guiding and holding blades are installed together with the inverted trapezoidal slots of the multi-channel distribution structure through the inverted trapezoidal connecting block.

3. The electrospinning nozzle according to claim 2, characterized in that: Each set of inverted trapezoidal slots includes two inverted trapezoidal slots, and a connecting seam is provided between the two inverted trapezoidal slots, which is connected to the drainage channel.

4. The electrospinning nozzle according to claim 3, characterized in that: The drainage seam and the connecting seam are correspondingly set and connected.

5. The electrospinning nozzle according to claim 1, characterized in that: The vertical gripping structure is connected to the connection hole of the multi-channel distribution structure through the central threaded hole on the mounting post.

6. The electrospinning nozzle according to claim 1, characterized in that: The number of inclined flow channels, gripping plates, and peripheral flow gripping blades are the same.

7. The electrospinning nozzle according to claim 6, characterized in that: The inclined flow channel and the gripping piece are respectively set.

8. The electrospinning nozzle according to claim 1, characterized in that: The drainage suture is open at the top and closed at the bottom.

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