Polygonal spinning equipment

Abstract

The invention discloses polygonal spinning equipment, and relates to the technical field of fiber textile, the polygonal spinning equipment comprises a plurality of spinning units, the adjacent spinning units are independently arranged, each spinning unit is provided with a liquid storage cavity and an inlet which is communicated with the liquid storage cavity and used for feeding a spinning solution, the liquid storage cavity extends outwards to form a spinning part communicated with the liquid storage cavity, and the spinning part is provided with a plurality of spinning holes. The curvature of the spinning part is larger than that of the liquid storage cavity, and the spinning part is provided with an outlet used for spraying out spinning jet flow. The polygonal spinning equipment adopts open spinning, and compared with needle type electrostatic spinning, the polygonal spinning equipment has a larger spinning jet injection liquid level and is less influenced by environment temperature, humidity and wind speed; the liquid storage cavities of the spinning units communicate with the power supply assemblies, so that independent power supply of the spinning solution in each liquid storage cavity can be achieved, the problems of uneven electric field intensity distribution and low electric field intensity caused by the fringe effect are reduced, and the quality and yield of electrostatic spinning are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of nanofiber preparation, and particularly to a polygonal spinning device. Background Art

[0002] Electrospinning is a special fiber manufacturing process in which a polymer solution or melt is ejected and spun in a strong electric field. Under the action of the electric field, the liquid droplet changes from a spherical shape to a conical shape, i.e., a "Taylor cone", and a fiber filament is extended from the tip of the cone. In this way, polymer filaments with a nanoscale diameter can be produced.

[0003] Currently, electrospun nanofibers have been widely studied in the field of intelligent and functional textiles. However, existing electrospinning technologies, including needle electrospinning and needleless electrospinning, both have their own defects. For example, during the process of needle electrospinning, the feeding channel, especially the tip of the needle, is prone to blockage, the output is low, and the edge effect is serious during large-scale implementation; in needleless electrospinning, the solvent volatilizes quickly, the open feeding volume is uncontrollable, and the quality of the nanofiber products is unstable. In addition, the nanofibers obtained by existing electrospinning technologies exist in the form of non-woven electrospun membranes. The fibers are extremely short, arranged randomly and disorderly, there is a lack of effective bonding between the fibers, the mechanical strength of the electrospun membrane is extremely low, it is difficult to support and use alone, and it is difficult to peel off from the surface of the fiber receiving device material.

[0004] Therefore, how to improve the output of electrospinning and improve the quality of electrospinning has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a polygonal spinning device to improve the output of electrospinning and improve the quality of electrospinning.

[0006] To achieve the above purpose, the present invention provides the following solutions:

[0007] The present invention provides a polygonal spinning device, which includes:

[0008] A plurality of spinning units, adjacent spinning units are independently arranged. Each spinning unit has a liquid storage cavity, and an inlet for placing a spinning solution, which is communicated with the liquid storage cavity. The liquid storage cavity extends outward to form a spinning part communicated with the liquid storage cavity. The curvature of the spinning part is greater than the curvature of the liquid storage cavity. An outlet for ejecting a spinning jet is provided on the spinning part;

[0009] A power supply assembly, each liquid storage cavity of each spinning unit is respectively communicated with the power supply assembly. The power supply assembly is used to supply power to the spinning solution in the liquid storage cavity, so that the spinning solution in the liquid storage cavity ejects a spinning jet from the outlet.

[0010] Preferably, the cross-section of the spinning unit is an N-sided polygon, where N≥3.

[0011] Preferably, the spinning part has a limiting area for reducing the overflow of the spinning solution.

[0012] Preferably, the polygonal spinning device includes a first spinning unit and a second spinning unit arranged in sequence from the inside to the outside. Both the first spinning unit and the second spinning unit have the liquid storage cavity and the spinning part, and the liquid storage cavity of the first spinning unit and the liquid storage cavity of the second spinning unit are respectively connected to the power supply assembly.

[0013] Preferably, the polygonal spinning device includes a plurality of rows of the spinning unit groups, and each spinning unit group includes a plurality of the spinning units;

[0014] Among them, the adjacent rows of the spinning unit groups are symmetrically arranged, or the adjacent rows of the spinning unit groups are arranged in the same direction;

[0015] And / or, the spinning units of the adjacent rows of the spinning unit groups are arranged in a staggered manner or in an aligned manner.

[0016] Preferably, the polygonal spinning device further includes a fiber receiving device arranged towards the outlet. The fiber receiving device and / or the spinning unit are connected with a driving assembly, and the driving assembly is used to drive the fiber receiving device and / or the spinning unit to move reciprocally.

[0017] Preferably, the polygonal spinning device includes a liquid supply assembly. The liquid supply assembly includes a primary liquid supply pipeline, the primary liquid supply pipeline is connected to a spinning solution supply source, the primary liquid supply pipeline is connected to a plurality of second-level liquid supply pipelines dispersed in strips, and each second-level liquid supply pipeline is connected to a plurality of third-level liquid supply pipelines dispersed in strips. The second-level liquid supply pipelines and the third-level liquid supply pipelines are all connected to the liquid storage cavity.

[0018] Preferably, the polygonal spinning device further includes an anti-coagulator. The anti-coagulator can apply a first force to the spinning solution in the liquid storage cavity, and the first force is used to prevent the spinning solution in the liquid storage cavity from solidifying.

[0019] Preferably, the power supply assembly includes a power source and a plurality of conductive parts, and the conductive parts are connected to the liquid storage cavity.

[0020] Preferably, the polygonal spinning device includes a spinning platform connected to the spinning unit and used to support the spinning unit. One end of the conductive part for connecting to the power source is located inside the spinning platform; an insulating layer is coated on the spinning platform.

[0021] The present invention has achieved the following technical effects compared with the prior art:

[0022] In the present invention, the polygonal spinning device includes a plurality of spinning units which are independently arranged adjacent to each other. Each spinning unit has a liquid storage cavity, and an inlet communicating with the liquid storage cavity for placing a spinning solution. The liquid storage cavity extends outward to form a spinning part communicating with the liquid storage cavity. The curvature of the spinning part is greater than that of the liquid storage cavity. An outlet for ejecting a spinning jet is provided on the spinning part; a power supply component is respectively connected to the liquid storage cavity of each spinning unit. The power supply component is used to supply power to the spinning solution in the liquid storage cavity so that the spinning solution in the liquid storage cavity ejects a spinning jet from the outlet.

[0023] Based on the above structure, compared with the prior art, the polygonal spinning device in the present invention has the following beneficial effects: ① The polygonal spinning device in the present invention is an open spinning device. The spinning part has an open spinning liquid surface. Compared with needle-type electrospinning, the present invention has a larger spinning jet ejection liquid surface, is less affected by temperature, humidity and wind speed, and avoids the problem of reduced fiber output caused by needle blockage.

[0024] ② It can be known from Gauss's theorem and tip effect, etc. that in the region where the surface curvature of a conductor is larger, that is, the region with a smaller curvature radius (curvature is the reciprocal of the curvature radius), the charge density is higher and the electric field strength is greater. Therefore, compared with other regions of the liquid storage cavity, because the spinning part has a larger curvature, that is, a smaller bending radius and a higher electric field strength, the spinning solution located in the spinning part of the present invention is excited by charges and converges at the sharp corners and their peripheries with a larger bending curvature, and multiple dense spinning jets are excited here, thereby further increasing the fiber gram weight and output of the spinning device in the present invention; at the same time, based on the above effects of the spinning part, compared with single-needle spinning, multi-needle spinning and needleless spinning in the prior art, the present invention reduces the external voltage required for spinning, reduces the production cost, and improves the safety during the spinning process.

[0025] ③ In the prior art, when a single power supply component is used to distribute power to multiple spinning heads, due to factors such as the length of the transmission path and contact resistance, the charge received by different spinning heads is different. Some spinning heads, especially those in the edge region, are likely to not be able to excite spinning jets due to insufficient charge, or the number of excited spinning jets is small, reducing the spinning output and quality of the spinning heads (the situation of reducing quality includes that when multiple spinning heads are regarded as a whole, if some spinning heads eject fewer spinning jets, it will lead to uneven fiber structure). However, since the liquid storage cavity of each spinning unit in the present invention is connected to a power supply component, the spinning solution in each liquid storage cavity can be independently powered, reducing the problems of uneven distribution of electric field strength and low electric field strength caused by edge effect, and then further improving the quality and output of electrospinning.

[0026] Based on the above factors, under the same width scale, compared with the single-needle spinning, multi-needle spinning and needleless spinning methods in the prior art, the polygonal spinning device in the present invention significantly improves the output and quality of electrospinning (the quality includes the structural uniformity of fibers), the safety during the spinning process, as well as the orientation and mechanical properties of the fibers. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0028] Figure 1 Cross-sectional schematic diagram of the spinning unit of some shapes in the present invention;

[0029] Figure 2 Cross-sectional schematic diagram of the first spinning unit and the second spinning unit;

[0030] Figure 3 Structural schematic diagram of the reverse alignment arrangement of two rows of spinning unit groups when the cross-section of the spinning unit is triangular;

[0031] Figure 4 Structural schematic diagram of the reverse dislocation arrangement of two rows of spinning unit groups when the cross-section of the spinning unit is triangular;

[0032] Figure 5 Structural schematic diagram of the same-direction alignment arrangement of two rows of spinning unit groups when the cross-section of the spinning unit is triangular;

[0033] Figure 6 Structural schematic diagram of the same-direction dislocation arrangement of two rows of spinning unit groups when the cross-section of the spinning unit is triangular;

[0034] Figure 7 Structural schematic diagram of the dislocation distribution of two rows of spinning unit groups when the cross-section of the spinning unit is square and the spinning unit rotates 45° clockwise;

[0035] Figure 8 Structural schematic diagram of a single row of spinning unit groups when the cross-section of the spinning unit is square and the spinning unit rotates 26° 33′ 54″ clockwise;

[0036] Figure 9 Structural schematic diagram of the same-direction dislocation distribution of two rows of spinning unit groups when the cross-section of the spinning unit is square and the spinning unit rotates 26° 33′ 54″ clockwise;

[0037] Among them, 1. First emission site; 2. Second emission site; 3. Third emission site; 4. Fourth emission site; 5. Fifth emission site; 6. Sixth emission site; 7. Seventh emission site; 8. Eighth emission site; 9. Ninth emission site; 10. Tenth emission site; 11. Eleventh emission site; 12. Twelfth emission site; 13. Spinning section; 20. Conductive part; 30. Inlet; 40. Bottom plate; 50. Side plate; 60. Fiber receiving device; 70. Conducting wire; 80. Spinning solution. Detailed implementation manners

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0040] It should be understood that in the single-needle spinning in the prior art, since the electric field intensity of the single needle is concentrated at the needle tip (the electric field intensity of the single needle refers to the electric field intensity generated by the charge applied to the spinning solution in the single needle), and since the spinning jet is only ejected through a single needle, the single-needle spinning is more affected by factors such as environmental temperature, humidity, and the viscosity of the spinning solution. The single needle is more likely to be blocked, resulting in a reduction in the output of the single-needle spinning.

[0041] In the large-scale needle spinning, that is, the multi-needle spinning (the gap between the needle arrangements is 30 - 50 mm), the electric field intensity is concentrated at multiple needle tips (the electric field intensity refers to the electric field intensity generated by the charge acting on the spinning solution in the needle). The distance between each needle is relatively close, which leads to a strong Coulomb repulsion between the spinning jets ejected from each spinning needle. The spinning jets ejected from the edge spinning needles will deviate from the center line, resulting in the situation of End effect, that is, the edge effect, so that the fibers generated by the edge spinning needles cannot be received by the receiving device, reducing the spinning output and spinning quality; and the mutual interference between the multiple spinning jets on both sides makes the electric field intensity received by the spinning needles in the middle position weaker, not enough to provide the ability required to form the spinning jet, which makes it difficult for the spinning needles in the middle position to form the spinning jet, easily resulting in uneven distribution of the fiber membrane along the width direction of the equipment, that is, the CD direction of the equipment; and, the multi-needle spinning is prone to problems such as dripping, splashing, and uneven electric field distribution and uneven fiber membrane thickness caused by the edge effect, further reducing the spinning efficiency and quality of the multi-needle spinning.

[0042] The use of the polygonal spinning device in the present invention can effectively increase the output of electrospinning, improve the quality of electrospinning, and enhance the safety during the spinning process. Details are as follows:

[0043] As Figures 1 to 9 shown, the present invention discloses a polygonal spinning device. The polygonal spinning device includes a plurality of spinning units, and adjacent spinning units are independently arranged. Each spinning unit has a liquid storage cavity, and an inlet 30 that communicates with the liquid storage cavity and is used for placing the spinning solution 80. A spinning part 13 that communicates with the liquid storage cavity extends outward from the liquid storage cavity. The curvature of the spinning part 13 is greater than that of the liquid storage cavity. An outlet for ejecting a spinning jet is provided on the spinning part 13. The liquid storage cavity of each spinning unit is respectively connected to a power supply component, and the power supply component is used to supply power to the spinning solution 80 in the liquid storage cavity, so that the spinning solution 80 in the liquid storage cavity ejects a spinning jet from the outlet.

[0044] Based on the above structure, compared with the prior art, the polygonal spinning device in the present invention has the following beneficial effects: ① The polygonal spinning device in the present invention is an open spinning device, and the spinning part 13 has an open spinning liquid surface. Compared with needle-type electrospinning, the present invention has a larger spinning jet ejection liquid surface, is less affected by temperature, humidity, and wind speed, and avoids the problem of reduced fiber output caused by needle blockage.

[0045] ② It can be known from Gauss's theorem and tip effect, etc., that in the region where the surface curvature of a conductor is larger, that is, the region with a smaller radius of curvature (curvature is the reciprocal of the radius of curvature), the charge density is higher and the electric field strength is greater. Therefore, compared with other regions of the liquid storage cavity, because the spinning part 13 has a larger curvature, that is, a smaller bending radius and a higher electric field strength, the spinning solution 80 located in the spinning part 13 of the present invention is excited by charges and converges at the sharp corners with a larger bending curvature and its surrounding areas, and multiple dense spinning jets are excited here, thereby further increasing the fiber gram weight and output of the spinning device in the present invention; at the same time, based on the above effects of the spinning part 13, compared with single-needle spinning, multi-needle spinning, and needleless spinning in the prior art, the present invention reduces the applied voltage required for spinning, reduces production costs, and improves the safety during the spinning process.

[0046] ③In the prior art, a single power supply component is used to distribute power to multiple spinning heads. Due to factors such as the length of the transmission path and contact resistance, the charge received by different spinning heads is different. Some spinning heads, especially those in the edge area, are likely to fail to generate spinning jets due to insufficient charge, or generate a small number of spinning jets, which reduces the spinning output and quality of the spinning heads (the situation of reducing quality includes that, as a whole, if some spinning heads eject fewer spinning jets, the fiber structure will be uneven). However, in the present invention, each liquid storage cavity of each spinning unit is connected to a power supply component, which enables independent power supply for the spinning solution 80 in each liquid storage cavity, reduces the problem of uneven distribution of electric field strength and low electric field strength caused by the edge effect, and further improves the quality and output of electrospinning;

[0047] ④Since the number of spinning jets generated by the polygonal spinning device in the present invention is extremely large, there is not enough space for each spinning jet to undergo lateral whipping, and the Coulomb repulsion force between the spinning jets is weak. Therefore, under the action of the relatively high electric field force of the spinning solution 80 in the spinning section 13, each Taylor cone directly ejects filaments in the vertical direction. After reaching the fiber receiving device 60, such as a receiving electrode, a receiving base cloth, or a dynamic fiber receiving device, the spinning jets are likely to form a highly oriented nanofiber material, improving the mechanical properties of the (nano) fiber material in the MD direction, that is, the direction in which the fiber is stretched; moreover, since the dense spinning jets are not conducive to the rapid volatilization of the spinning solution 80, the spinning jets have not completely solidified when reaching the fiber receiving device 60 during the electrospinning process. Therefore, the nanofibers are self-bonded online by means of a semi-solid binder (the semi-solid binder can be understood as a solvent) (online self-bonding means that during the electrospinning process, the ejected fibers have not completely solidified and still contain some solvent. Therefore, when these fibers come into contact with each other, they can directly bond together without additional binder, that is, the solvent bonding method, and the solvent bonding method is a type of chemical bonding method). The online self-bonding enables the formation of a firm connection at the fiber intersection points, enhancing the integrity of the electrospun product, that is, the fiber membrane, so that the fiber membrane can still maintain a stable shape after the solvent has completely volatilized. Due to the stacking method of the fibers and the action of online self-bonding, the fiber membrane has a certain porosity and three-dimensional grid structure, which helps to disperse the external force received by the fiber membrane, enabling the fiber membrane to have relatively high mechanical strength, being able to support and be applied independently, and after the solvent has completely volatilized, the internal structure of the fiber tends to be stable and no longer has adhesiveness, so it will not adhere to the surface of the fiber receiving device 60 and can exist independently. Furthermore, appropriate surface treatment can be carried out on the surface of the fiber receiving device 60, such as coating an anti-adhesion layer, so that the fiber membrane can be more easily peeled off from the fiber receiving device 60 and maintain a complete structure;

[0048] Based on the above factors, under the same width scale, compared with the single-needle spinning, multi-needle spinning and needleless spinning methods in the prior art, the polygonal spinning device in the present invention significantly improves the output and quality of electrospinning (the quality includes the structural uniformity of the fibers), the safety during the spinning process, as well as the orientation and mechanical properties of the fibers.

[0049] Among them, several spinning units can be sequentially arranged along the width direction of the device, that is, the width direction of the spinning die formed by the polygonal spinning device. The spinning unit can be understood as a housing with a liquid storage cavity for storing the spinning solution 80, so that the spinning solution 80 will not leak from the liquid storage cavity by itself, as Figure 3 shown, the spinning unit includes a bottom plate 40, and a plurality of side plates 50 provided on and connected to the bottom plate 40 and surrounding to form the liquid storage cavity. The spinning solution 80 in the liquid storage cavity has an appropriate viscosity so as not to reduce the fiber output and quality. For example, the viscosity of the spinning solution 80 needs to enable the fibers to reach the strength and elongation required by the working conditions. As Figure 3 shown, the spinning part 13 can specifically be a sharp corner; when the spinning device starts spinning, the power supply component continuously infuses charges into the spinning solution 80 in the liquid storage cavity. A large number of charges quickly migrate to the liquid surface junction of the spinning solution 80 and the spinning unit, and converge at the sharp corner with a larger bending curvature and its periphery, where multiple dense spinning jets are excited.

[0050] Moreover, a limiting area is provided at the sharp corner of the spinning part 13 of the spinning unit. The limiting area can specifically be a chamfer structure, such as a 45° inclined plane or an arc transition area, thereby increasing the flow resistance of the spinning solution 80 at the sharp corner, and using surface tension to constrain the solution so that it concentrates at the sharp corner to form a stable Taylor cone instead of overflowing along the edge.

[0051] The spinning unit can be used alone for the small-scale preparation of laboratory-grade fiber materials, or, as Figures 3 to 9 shown, the polygonal spinning device can include multiple rows or columns of spinning unit groups. The shapes of adjacent spinning units can be the same or different. Adjacent rows or columns of spinning unit groups can be aligned (alignment means that the spinning units in adjacent rows / columns correspond one by one) or misaligned. By using multiple spinning units, the spinning area can be effectively expanded, the fiber deposition can be made more uniform, and the problem of density unevenness caused by excessive or too little local spinning amount can be avoided. And this is equivalent to increasing the number of spinning units, and more nanofibers can be produced at the same time, thus significantly improving the output per unit time; therefore, under the same width scale, the structural uniformity and output of the fiber materials obtained by using the spinning device in the present invention are better than those of traditional multi-needle electrospinning and existing needleless electrospinning.

[0052] Figures 1 to 9 The specific structures of the liquid supply component communicated with the inlet 30 and the power supply component are omitted in the figure. In the figure It represents a sharp corner, which is also the spinning jet emission site and the spinning site where the spinning jets are most concentrated.

[0053] As Figure 1 shown, the cross-section of the spinning unit is an N-sided polygon, where N≥3, that is, the number of sharp corners ≥3; alternatively, the spinning unit can also be a special-shaped combined structure with a circular cross-section and a sharp-corner structure. Several sharp-corner structures are arranged on the circular structure, and the sharp-corner structure and the circular structure are connected. Regardless of the shape and structure of the spinning unit, and whether the spinning unit is symmetric or not, as long as the setting of the spinning unit can achieve the effect of "increasing the spinning jet and improving the spinning output" mentioned above, it can be used as the spinning part 13 in the present invention. The materials of the spinning unit include but are not limited to metals, plastics, glasses, ceramics, woods, and carbons, as long as they can meet the requirements of electrospinning in the present invention.

[0054] As Figure 2 shown, the polygonal spinning device includes a first spinning unit and a second spinning unit arranged in sequence from the inside to the outside. Both the first spinning unit and the second spinning unit have a liquid storage cavity and a spinning part 13, and the liquid storage cavity of the first spinning unit and the liquid storage cavity of the second spinning unit are respectively connected to a power supply component. Different types of spinning fluids can be fed into the first spinning unit and the second spinning unit respectively. The first spinning unit can be a core layer spinning unit, and the second spinning unit can be a skin layer spinning unit. After electrospinning, a nanofiber material with a core-shell structure can be obtained.

[0055] As Figure 3 shown, the polygonal spinning device includes two rows of spinning unit groups arranged in reverse alignment and having a triangular cross-section. The distance D between adjacent spinning units in the spinning unit group is 0. When the distance D between adjacent two rows of spinning unit groups is relatively small, specifically when D<10mm, the two rows of spinning unit groups geometrically nucleate to form a field distribution similar to a "parallel plate". Charges are likely to form a reverse electric field in space, weakening the spinning only on the outer side of the spinning unit, that is, in the direction away from the other row of spinning unit groups. Spinning occurs at the sharp corners of the spinning unit and at two adjacent side edges, but the jet density around the sharp corners is relatively high. The overlapping of the spinning jet densities of the front and rear rows of spinning units is enhanced, and the spinning unit and / or the fiber receiving device 60 is connected to a driving component. The driving component can specifically be a linear driving device such as a cylinder or a hydraulic cylinder. By driving the spinning unit and / or the fiber receiving device 60 to reciprocate, such as reciprocating transversely in the width direction of the device, the problem of uneven structure of the nanofiber material can be solved by driving the spinning unit or the fiber receiving device 60 to transversely move. When the distance between adjacent two rows of spinning unit groups is large enough, spinning can occur on both the inner and outer sides of the spinning unit (the inner side refers to the direction where the spinning unit is close to the other row of spinning unit groups, for example Figure 3The direction in which the upper row of spinning unit groups faces the lower row of spinning unit groups is the inner side, and the direction in which the upper row of spinning unit groups faces away from the lower row of spinning unit groups is the outer side), with a larger output of nanofibers and a more uniform structure of the nanofiber material.

[0056] As Figure 4 shown, the polygonal spinning device includes two rows of spinning unit groups arranged in reverse dislocation and having a triangular cross-section. The distance D between adjacent spinning units in the spinning unit group is 0. At this time, the spinning is performed on the outer side of the spinning unit, that is, the side away from the other row of spinning unit groups, and at the sharp corners and two adjacent side edges, but the jet density around the sharp corners is relatively high. The spinning jet densities of the two rows of spinning unit groups compensate for each other, and the obtained nanofibers have a uniform structure. When the distance between the two rows of spinning unit groups is increased, and / or the spinning unit and / or the fiber receiving device 60 are driven by the driving assembly to traverse, the output of nanofibers and the structural uniformity can be further improved.

[0057] As Figure 5 shown, the polygonal spinning device includes two rows of spinning unit groups arranged in the same direction and having a triangular cross-section. The distance between adjacent spinning units in the spinning unit group is D. The spinning is performed on the outer side of the spinning units in each row of spinning unit groups, that is, the side away from the other row of spinning unit groups. Figure 5 Spinning is performed at the bottom edges and two adjacent sharp corners of the spinning units in the upper row of spinning unit groups, but the jet density in the middle of the bottom edge is relatively low. Spinning is performed at the sharp corners and two adjacent side edges of the spinning units in the lower row of spinning unit groups, but the jet density around the sharp corners is relatively high. Just the spinning jet densities of the two rows compensate for each other, and the obtained nanofibers have a uniform structure.

[0058] As Figure 6 shown, the polygonal spinning device includes two rows of spinning unit groups arranged in reverse dislocation and having a triangular cross-section. The distance between adjacent spinning units in the spinning unit group is D. When the row spacing T between adjacent rows of spinning unit groups is very small, specifically T < 10 mm, each spinning unit spins only on the outer side, that is, the side away from the other row of spinning unit groups; spinning is performed at the triangular bottom edges and two adjacent sharp corners of each row of spinning units, but the jet density in the middle of the bottom edge is relatively low. The front and rear rows are offset by one triangular side length. Just the spinning jet densities of the front and rear rows compensate for each other, and the obtained nanofibers have a uniform structure; driving the spinning unit or the fiber receiving device 60 to traverse by the driving assembly results in a more uniform structure of the obtained nanofiber material; where ① - ⑧ respectively represent the first - eighth (spinning jet) emission sites.

[0059] As Figure 7As shown in the figure, the polygonal spinning device includes a spinning unit group with two rows arranged in a staggered manner, a square cross-section, and the spinning units rotated clockwise by 45°. The distance between adjacent spinning units in the spinning unit group is D. When the row spacing T between adjacent rows of the spinning unit group is very small, specifically T < 10 mm, only the outer side of the double-row triangular spinning units, that is, the side facing away from the other spinning unit group, sprays filaments; each spinning unit sprays filaments at the square outer sharp corners and two adjacent side edges, but the jet density around the sharp corners is relatively high and the jet density at the side edges is relatively low. The front and rear rows are arranged in a staggered manner, and just the spinning jet densities of the front and rear rows complement each other, resulting in a uniform structure of the nanofiber material; the spinning unit and / or the fiber receiving device 60 is connected to a driving component. The driving component can specifically be a linear driving device such as a cylinder or a hydraulic cylinder. By driving the spinning unit and / or the fiber receiving device 60 to reciprocate, for example, reciprocating transversely in the opposite direction along the width of the device, a nanofiber material with a more uniform structure can be obtained; among them respectively represent the first (spinning jet) emission site 1, the second (spinning jet) emission site 2, the third (spinning jet) emission site 3, the fourth (spinning jet) emission site 4, the fifth (spinning jet) emission site 5, the sixth (spinning jet) emission site 6, the seventh (spinning jet) emission site 7, the eighth (spinning jet) emission site 8, the ninth (spinning jet) emission site 9, the tenth (spinning jet) emission site 10, the eleventh (spinning jet) emission site 11, and the twelfth (spinning jet) emission site 12.

[0060] As Figure 8 shown in the figure, the polygonal spinning device includes a row of spinning unit groups arranged side by side, a square cross-section, and the spinning units rotated clockwise by 26° 33′ 54″. The distance between adjacent spinning units in the spinning unit group is D, and D = 0.44721 times the side length of the square of the spinning unit: This arrangement can make the spinning jets at each square sharp corner form an equidistant and uniform distribution along the width direction of the fiber receiving device 60 surface after being projected, resulting in a uniform structure of the nanofiber material; the spinning unit and / or the fiber receiving device 60 is connected to a driving component. The driving component can specifically be a linear driving device such as a cylinder or a hydraulic cylinder. By driving the spinning unit and / or the fiber receiving device 60 to reciprocate, for example, reciprocating transversely in the opposite direction along the width of the device, a nanofiber material with a more uniform structure can be obtained; among them respectively represent the first to twelfth (spinning jet) emission sites.

[0061] As Figure 9As shown, the polygonal spinning device includes a spinning unit group formed by arranging two rows of spinning units in a same-direction staggered manner and rotating the spinning units with a square cross-section clockwise by 26°33′54″. The distance between adjacent spinning units in the spinning unit group is D, and D = 0.44721 times the side length of the square. When the distance T between adjacent rows of spinning unit groups is large enough. Specifically, when T > 30 mm, the Coulomb repulsion force between the spinning jets of the spinning unit groups in the two rows can be overcome. This arrangement can make the spinning jets at the square sharp corners of each spinning unit project onto the surface of the fiber receiving device 60 and form an equidistant and uniform distribution along the width direction of the device, and then a nanofiber material with a uniform structure can be obtained; the structure of the nanofiber material obtained by driving the spinning unit or the fiber receiving device 60 to traverse by the driving assembly is more uniform; among them respectively represent the first to twelfth (spinning jet) emission sites, and the jet density is Figure 8 about twice that of

[0062] When the distance D between adjacent polygonal spinning units and the row distance T are large enough, specifically, when D > 30 mm and T > 30 mm, the Coulomb repulsion force between adjacent jets can be completely overcome, and each spinning unit can spin independently, thus further greatly improving the spinning efficiency and the output of nanofibers

[0063] In the present invention, the power supply assembly includes a power source and a plurality of conductive members 20 communicated with the liquid storage cavity. The conductive members 20 are connected to the power source. A power supply interface can be opened at the bottom or side wall of the spinning unit, so that the conductive members 20 are connected to the power source through a wire 70 of a type such as metal through the power supply interface; and after adjacent conductive members 20 are connected in series, they can be led out from the middle bottom position of the spinning unit or the power supply interfaces on both sides of the spinning unit; and a sealing member such as a sealing ring needs to be provided between the power supply interface and the wire 70 to prevent the spinning solution 80 from leaking. Since the power source is communicated with the spinning solution 80 in the liquid storage cavity and the spinning part 13 through the conductive members 20, when the spinning device needs to spin, the power source is started, and the power source continuously infuses charges into the spinning solution 80 in the liquid storage cavity and the spinning part 13, continuously charges the spinning solution 80. A large number of charges quickly migrate to the liquid surface junction of the spinning solution 80 and the spinning unit, and converge at the sharp corners and their peripheries with a larger bending curvature. Multiple dense spinning jets are excited here and ejected from the outlet or the spinning channel to form a single row or double row or multiple rows of spinning jets. Moreover, when the power supply assembly in the present invention supplies power to the spinning solution 80, it is directly communicated with the spinning solution 80, which reduces the electric field strength required for the spinning solution 80 to emit spinning jets and improves safety

[0064] Among them, the conductive member 20 can also be called a charge transporter. The conductive member 20 can have a symmetric or asymmetric geometric structure. Alternatively, multiple conductive members 20 can be dispersed and arranged in the liquid storage cavity, such as arranging multiple rows or a single row, and are connected to a (high-voltage) power supply through a wire 70 located at the geometric center of the conductive member 20 or at both ends of the spinning unit. When at least two rows of conductive members 20 are provided, the conductive members 20 can be symmetrically arranged along the geometric center line of the cross-section of the spinning unit and are connected to a (high-voltage) power supply through a wire 70 located at the geometric center, middle, or both ends of the spinning unit; or, if the size of the conductive member 20 is large enough, only one conductive member 20 can be provided in the liquid storage cavity. At this time, the conductive member 20 is a continuous integral structure. The cross-section of the liquid storage cavity inside the spinning unit can be a symmetric structure. The conductive member 20 can be arranged perpendicular or inclined to the bottom plate 40; the top of the conductive member 20 can have a tip or no tip.

[0065] When the conductive member 20 is a metal rod, such as a solid needle (or a row of needles), arranged perpendicular to the bottom plate 40, if a single row of conductive members 20 is provided, the single row of conductive members 20 can be arranged on the geometric center line at the bottom of the spinning unit. If at least two rows of conductive members 20 are provided, the conductive members 20 can be arranged at symmetric positions on both sides of the center line at the bottom of the spinning unit, that is, symmetrically arranged along the geometric center line of the cross-section of the spinning unit, so as to make the electric field intensity and the nanofibers evenly distributed along the length direction of the spinning unit, further improving the uniformity of the nanofibers and the electrospun membrane structure, or arranged at the geometric center point or other corresponding positions inside each spinning unit. The top of the conductive member 20 can be any symmetric or asymmetric geometric shape with a tip. At this time, the conductive member 20 can be arranged at the bottom of the spinning unit, that is, the liquid storage cavity, and can be arranged at the geometric center of the spinning unit or deviate from the geometric center, close to the outer side of the spinning unit. The geometric shape, material type, height relative to the spinning liquid surface, number, and arrangement density of the conductive member 20 can all be adjusted as needed to optimize the electric field intensity and ensure that the electric field intensity distribution of the spinning liquid surfaces in different spinning units within the same row is uniform; the conductive member 20 includes but is not limited to components made of any metal material, and its top can be above, below, or flush with the spinning liquid surface.

[0066] Alternatively, the conductive member 20 can also be omitted, and the wire 70 connected to the power supply is directly connected to the spinning solution 80 in the liquid storage cavity. At this time, a power supply with a higher voltage needs to be selected, or the receiving distance between the fiber receiving device 60 and the spinning unit needs to be shortened to provide sufficient electrostatic force to the spinning solution 80 to promote the spinning solution 80 to generate a Taylor cone and a spinning jet, and then form fibers. The power supply can specifically be a DC power supply, an AC power supply, a combined DC and AC power supply, or a pulsed power supply.

[0067] One end of the conductive member 20 extending into the liquid storage cavity is located above the liquid level of the spinning solution 80, or below the liquid level of the spinning solution 80, or flush with the liquid level of the spinning solution 80 (when one end of the conductive member 20 extending into the liquid storage cavity is flush with the liquid level of the spinning solution 80, it means that one end of the conductive member 20 extending into the liquid storage cavity is flush with the initial liquid level of the spinning solution 80, that is, the liquid level before spinning starts). The setting method of the other end of the conductive member 20 depends on the working conditions, as long as the setting method of the other end of the conductive member 20 can supply power to the spinning solution 80 to meet the requirements of electrospinning in the present invention. The number of spinning jets emitted can be regulated by the voltage applied to the spinning solution 80 by the power supply assembly. By using conductive members 20 with different materials, different shapes, different array structures and arrangement methods, the magnitude and distribution of the electric field strength can be precisely regulated, so as to minimize or even completely eliminate the edge effect caused by multiple jets during the electrospinning process. When the conductive member 20 is located below the spinning liquid level or the wire 70 is directly connected to the spinning solution 80 and an insulating material spinning unit is used, the charges are all used for spinning during the electrospinning process, and air breakdown will not occur, and continuous, stable, safe and efficient production of nanofiber materials can be realized.

[0068] The distance A between the liquid level of the spinning solution 80 and the bottom plate 40 is within a preset range, such as 0-20 mm, specifically within 0-10 mm, to prevent the spinning solution 80 in the spinning part 1320 from spreading upward and affecting the normal electrospinning process. If A is too large, it is easy to cause the voltage applied to the spinning solution 80 to be insufficient to form a spinning jet of the spinning solution 80, resulting in problems such as wire breakage or uneven spinning; if A is too small, it is easy to cause the spinning solution 80 content to be too small, resulting in discontinuous spinning.

[0069] The spinning device further includes a liquid supply assembly. The liquid supply assembly includes a primary liquid supply pipeline, the primary liquid supply pipeline is connected to a spinning solution 80 supply source, the primary liquid supply pipeline is connected to a number of secondary liquid supply pipelines dispersed in strips, and each secondary liquid supply pipeline is connected to a number of tertiary liquid supply pipelines dispersed in strips. The primary liquid supply pipeline, the secondary liquid supply pipeline, and the tertiary liquid supply pipeline are all connected to the liquid storage cavity. When the spinning device starts spinning, the spinning solution 80 supply source transports the spinning solution 80 to the main liquid supply path, and the spinning solution 80 flows through the primary liquid supply pipeline, the secondary liquid supply pipeline, and the tertiary liquid supply pipeline in sequence to reach the corresponding liquid storage cavity and the spinning part 13, so that the spinning solution 80 is evenly distributed in the liquid storage cavity and the spinning part 13. Among them, the spinning solution 80 supply source includes a storage tank storing the spinning solution 80, and a conveying member, such as a pump, that provides power for the spinning solution 80 in the storage tank so that the spinning solution 80 can reach the liquid storage cavity and the spinning part 13 through the primary liquid supply pipeline, the secondary liquid supply pipeline, and the tertiary liquid supply pipeline. And if the working conditions require, the spinning solution 80 supply source further includes heating elements, such as heating wires, for adjusting the temperature and humidity of the spinning solution 80, and humidity adjusting members, such as humidifiers, etc. Among them, the number of strips ≥ 2, and the specific number depends on the working conditions.

[0070] Furthermore, in the present invention, the distribution of the spinning solution 80 adopts a multi-stage fluid distribution method of "dividing into two" with three or more levels to ensure that the spinning solution 80 can be evenly distributed in the liquid storage cavity and the spinning part 13. Specifically, for the convenience of understanding the "dividing into two" fluid distribution method, the "dividing into two" fluid distribution method at the third level is taken as an example for illustration: the input end of the first-level liquid supply pipeline is connected to the spinning solution 80 supply source, the first-level liquid supply pipeline is respectively connected to the input ends of two second-level liquid supply pipelines, and the second-level liquid supply pipelines are respectively connected to the input ends of two third-level liquid supply pipelines. Among them, the first-level liquid supply pipeline can be arranged along the first direction, the two second-level liquid supply pipelines can extend from the side of the first-level pipeline towards the liquid storage cavity and the spinning part 13, and the third-level liquid supply pipeline can extend towards other areas of the liquid storage cavity and the spinning part 13. Since the distribution of the first-level liquid supply pipeline, the second-level liquid supply pipeline, and the third-level industrial pipeline is in a "tree shape" at this time, the "dividing into two" fluid distribution method with three or more levels adopted in the present invention can also be called "tree-shaped fluid distribution", which enables the spinning solution 80 to diffuse in multiple directions and gradually diffuse into all the liquid storage cavities and the spinning part 13, reducing the "dead angle" of liquid supply and improving the uniformity of the distribution of the spinning solution 80 in the liquid storage cavity and the spinning part 13, and improving the spinning quality. Through the above liquid supply assembly, closed-loop uniform and controllable liquid feeding is realized, and the problems of uncontrollable liquid feeding amount and solvent volatilization in the existing needleless electrospinning process are solved.

[0071] The multi-sided spinning device in the present invention further includes a spinning platform (which can be understood as a bracket) disposed below the spinning unit, connected to the spinning unit, and supporting the spinning unit. The length and width of the spinning are matched with the size of the spinning unit and can be assembled with the spinning unit (in the vertical direction) by means of slots, screws, etc. The spinning platform can be made of insulating materials and has a certain accommodation space inside; the insulating materials include but are not limited to polymer materials, resins, ceramics, glass, wood, or their composite materials and coatings, as long as they can meet the insulation requirements. The present invention does not specifically limit the shape of the bracket, as long as it can shield the wire 70 and the conductive part 20 in its accommodation space, it belongs to the protection scope of the present invention.

[0072] Inside the spinning platform, there are sites connected to the power supply and channels for the wire 70 to pass through; one or both ends of the conductive member 20 for electrically connecting to the power supply and the wire 70 are located in the accommodation space to prevent the conductive member 20 and the wire 70 from interfering with the electric field intensity of the spinning liquid surface and affecting the uniformity of the electric field intensity distribution. The primary liquid supply pipe, secondary liquid supply pipe, and tertiary liquid supply pipe mentioned above can also be arranged in the accommodation space, thereby realizing the closed, controllable, and precise liquid feeding of the spinning equipment; the closure includes the closure of the liquid supply pipe, and the controllable and precise liquid feeding can be achieved by the pumps and flow valves arranged on the primary liquid supply pipe and / or secondary liquid supply pipe and / or tertiary liquid supply pipe. The above-mentioned liquid supply pipe and the arrangement of the conductive member 20 are required to ensure that the power supply voltage and the spinning solution 80 are evenly distributed along the width direction of the equipment, that is, the length direction of the spinning unit, to ensure the uniformity of the fiber structure.

[0073] Moreover, the spinning equipment in the present invention further includes driving equipment. There are several driving equipment, which are connected to the conductive member 20 and can drive the conductive member 20 to rotate and / or move. When the driving equipment drives the conductive member 20 to rotate, the driving equipment can specifically be a rotary driving equipment such as a rotary motor; when the driving equipment drives the conductive member 20 to move, the driving equipment can specifically be a linear driving equipment such as a first cylinder or a first hydraulic cylinder; when the driving equipment can both drive the conductive member 20 to rotate and drive the conductive member 20 to move, the driving equipment includes a second rotary motor. The output end of the second rotary motor is connected to the conductive member 20, and the conductive member 20 is driven to rotate by the second rotary motor. The second rotary motor is fixed on the support plate, and the support plate is connected to the output end of the second cylinder or the second hydraulic cylinder, and the support plate, the second rotary motor, and the conductive member 20 are driven to move by the second cylinder or the second hydraulic cylinder. The driving equipment enables the conductive member 20 to move within a certain range under the spinning liquid surface, such as translation and / or rotation. Ultrasonic vibrators can also be added under the spinning liquid surface to stimulate the spinning liquid surface to generate multiple spinning jets, stimulate the macromolecules in the spinning solution 80 to move violently, generate heat by friction, and prevent the liquid surface from solidifying.

[0074] In addition, the spinning device of the present invention further includes an anti-coagulation device, which is used to apply a first force to the spinning solution 80 in the liquid storage cavity when the spinning device is operating. The first force is used to prevent the spinning solution 80 from solidifying, at least preventing the surface of the spinning solution 80 from solidifying, so as to ensure the continuity and stability of the spinning process. The anti-coagulation device can specifically be a structure such as an ultrasonic oscillator that can apply a first force to the spinning solution 80 in the liquid storage cavity. The ultrasonic vibrator (vibrator) in the ultrasonic oscillator can directly apply high-frequency and low-amplitude vibrations to the spinning solution 80, stimulating the high polymers in the spinning solution 80 to move violently and generate heat by friction, effectively preventing the liquid surface of the spinning solution 80 from solidifying, and assisting in exciting more spinning jets, improving the electrospinning efficiency and the output of nanofibers. The power supply of the ultrasonic oscillator can use a commercial AC power supply or other power supplies that can supply the required electrical energy to the ultrasonic oscillator. The anti-coagulation device can be arranged inside the spinning unit or under the spinning platform. When the anti-coagulation device is an ultrasonic oscillator, the anti-coagulation device needs to be connected to the spinning unit or the spinning platform. The ultrasonic vibrator and the ultrasonic oscillator mentioned above are prior arts, and their specific structures will not be elaborated here.

[0075] The multi-sided spinning device of the present invention not only improves the structural uniformity of nanofibers and electrospun membranes and the product quality, but also the dense and multi-row spinning jets obtained on the fiber receiving device by using a single-row or multi-row array arrangement greatly improve the output and quality of nanofibers. Since the actual distance between adjacent spinning jets is relatively large, the Coulomb repulsion and the Endeffect (edge effect) caused are very small, so the output of nanofibers is high and the structure is uniform. Therefore, the structural uniformity and output of the nanofiber material obtained by the present invention are superior to those of traditional multi-needle electrospinning and existing needleless electrospinning under the same width scale. The anti-coagulation device can effectively prevent the surface of the spinning solution from solidifying, providing the continuity and stability of the spinning process. The adoption of the multi-sided spinning unit and the power supply component endow the electrospinning process with the characteristics of high electric field strength and low voltage, which are not likely to cause safety accidents of air breakdown, and save energy and reduce costs. While increasing the output of nanofibers, a nanofiber material with high orientation, high mechanical strength, non-sticking to the surface of the fiber receiving device, and capable of independent support and application can be obtained. The present invention has the characteristics of closed-loop controllable liquid feeding, continuous safe production, as well as high output, high uniformity, and high stability, and can be used for large-scale preparation of nanofiber yarns, flocs, and conventional electrospun membranes.

[0076] The continuous controllable closed liquid feeding method adopted by the present invention improves the product quality stability. In addition, the spinning unit adopted by the present invention has a very high electric field strength, and high-quality and high-yield nanofibers can be achieved without a very high spinning voltage. Moreover, the electrospinning process is continuous, controllable, stable and safe. The formed highly oriented continuous nanofibers improve the mechanical properties of the product, do not stick to the surface of the fiber receiving device, are easy to peel and form, and can be independently supported for use; the obtained highly oriented continuous nanofibers, in addition to directly forming an electrospun membrane, are very easy to be bundled and twisted into nanofiber yarns after being received. It can also be prepared into nanofiber nonwovens through web curtain receiving, web laying and network fixing.

[0077] Matters not covered by the present invention are applicable to the prior art.

[0078] Specific examples are used in the present invention to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention. For example, any improvement or large-scale and industrialized implementation of electrospinning technology based on the basic principle of the present invention, including but not limited to material replacement, structural change, fluid distribution, improvement of electric field strength and distribution of all structural components involved in the present invention, etc., are within the protection scope of the present invention.

Claims

1. A multi-sided spinning device, characterized in that, The polygonal spinning device includes: A plurality of spinning units, adjacent spinning units are independently arranged. Each spinning unit has a liquid storage cavity, and an inlet for placing a spinning solution, which is communicated with the liquid storage cavity. The liquid storage cavity extends outward to form a spinning part communicated with the liquid storage cavity. The curvature of the spinning part is greater than that of the liquid storage cavity. An outlet for ejecting a spinning jet is provided on the spinning part. A power supply assembly. The liquid storage cavity of each spinning unit is respectively communicated with the power supply assembly. The power supply assembly is used to supply power to the spinning solution in the liquid storage cavity, so that the spinning solution in the liquid storage cavity ejects a spinning jet from the outlet.

2. The polygonal spinning device according to claim 1, characterized in that, The cross-section of the spinning unit is an N-sided polygon, where N≥3.

3. The polygonal spinning device according to claim 1, characterized in that, The spinning part has a limiting area for reducing the overflow of the spinning solution.

4. The polygonal spinning device according to claim 1, characterized in that, The polygonal spinning device includes a first spinning unit and a second spinning unit arranged in sequence from inside to outside. Both the first spinning unit and the second spinning unit have the liquid storage cavity and the spinning part. The liquid storage cavity of the first spinning unit and the liquid storage cavity of the second spinning unit are respectively communicated with the power supply assembly.

5. The polygonal spinning device according to claim 1, characterized in that, The polygonal spinning device includes a plurality of rows of the spinning unit groups. Each spinning unit group includes a plurality of the spinning units. Among them, adjacent rows of the spinning unit groups are symmetrically arranged, or adjacent rows of the spinning unit groups are arranged in the same direction. And / or, the spinning units of adjacent rows of the spinning unit groups are arranged in a staggered manner or in an aligned manner.

6. The polygonal spinning device according to claim 1, wherein, The polygonal spinning device further includes a fiber receiving device arranged towards the outlet. The fiber receiving device and / or the spinning unit are connected with a driving assembly. The driving assembly is used to drive the fiber receiving device and / or the spinning unit to move reciprocally.

7. The polygonal spinning device according to claim 1, characterized in that, The polygonal spinning device includes a liquid supply assembly. The liquid supply assembly includes a primary liquid supply pipeline, which is communicated with a spinning solution supply source. The primary liquid supply pipeline is communicated with a plurality of second-level liquid supply pipelines dispersed in strips. Each second-level liquid supply pipeline is communicated with a plurality of third-level liquid supply pipelines dispersed in strips. The second-level liquid supply pipelines and the third-level liquid supply pipelines are both communicated with the liquid storage cavity.

8. The polygonal spinning device according to claim 1, wherein, The polygonal spinning device further includes an anti-coagulator. The anti-coagulator can apply a first force to the spinning solution in the liquid storage cavity. The first force is used to prevent the spinning solution in the liquid storage cavity from solidifying.

9. The polygonal spinning device according to claim 1, characterized in that, The power supply assembly includes a power source and a plurality of conductive members, and the conductive members are communicated with the liquid storage cavity.

10. The polygonal spinning device according to claim 9, characterized in that, The polygonal spinning device includes a spinning platform connected to the spinning unit and used to support the spinning unit. One end of the conductive member for connecting to the power source is located inside the spinning platform; an insulating layer is coated on the spinning platform.

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