A printed spiral linear electrospinning nozzle and method of use thereof

Abstract

The application discloses a printing type spiral linear electrostatic spinning nozzle and a use method thereof, and belongs to the technical field of electrostatic spinning nozzle. The nozzle comprises a nozzle box, a nozzle cover, a metal block located in the middle of the nozzle box, and scraping liquid plates fixed symmetrically on the two sides of the metal block. A liquid storage groove is formed in the top surface of the metal block, and the bottom surface of the metal block is fixed to the nozzle box. The metal block is provided with a through hole penetrating through the liquid storage groove. A tapered scraping liquid hole is formed in the middle of the scraping liquid plate and communicates with the through hole. A reverse conical scraping liquid hole is formed in the inside of the tapered scraping liquid hole. The nozzle box is symmetrically provided with wire passing holes for the spiral electrode to penetrate, and the wire passing holes communicate with the through hole. The nozzle utilizes spiral vortex to make tangential peeling movement of the spinning solution on the spiral electrode to generate shearing force, so that the spinning solution is peeled off from the thread groove surface of each position of the spiral electrode. The nozzle avoids the residue of the spinning solution at the pre-coating position of the spiral electrode, improves the uniformity and purity of subsequent solution coating, and improves the spinning yield.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrospinning, and particularly relates to a printing type spiral linear electrospinning nozzle and a use method thereof. BACKGROUND

[0002] Electrospinning refers to a process of forming polymer nanofibers by generating and extending a liquid jet of a polymer spinning solution or a polymer melt when the liquid jet is exposed to a strong external electrostatic field. In the presence of an external force, the liquid jet stability of a non-Newtonian fluid changes significantly, resulting in a very long liquid filament of the polymer. When the electric field on the surface of the polymer spinning solution overcomes the surface tension, electrospinning occurs, resulting in further elongation of the charged jet into a filament. Electrospun nanofibers show great application potential in the fields of tissue engineering, drug delivery, catalysis, sensors, energy conversion and storage, reinforcement and environmental protection due to their high air / liquid permeability, large surface area to volume ratio. The fiber diameter is adjustable and easy to functionalize.

[0003] People have spent considerable effort on the manufacture of electrospun nanofibers, but there is still a need for efficient and low-cost technology to produce nanofibers with guaranteed quality. Traditional single-needle electrospinning devices usually use a metal hollow capillary as a nozzle. Due to the fact that only one jet is excited at a time during the spinning process, the metal hollow capillary is blocked during the spinning process, so the production capacity is limited. Multi-needle electrospinning is one of the main methods to increase the production of nanofibers. In the spinning process, multiple single-needles are assembled according to a specific arrangement to increase the number of nozzles. However, the inherent problems related to multi-needle electrospinning include mutual interference of electric fields and blockage of needles by polymer spinning solution, which ultimately makes it impossible to implement on a large scale in industry. Therefore, the spinning solution is now coated onto a spiral wire electrode through a special device, high voltage is passed through the spiral wire electrode, and the spinning solution is stretched into a jet filament on the wire electrode to form a fiber. However, the spinning solution coated on the spiral wire electrode cannot be completely stretched into a jet filament to form a fiber. The residual spinning solution will accumulate on the spiral wire electrode. The solvent in the spinning solution is extremely volatile when the free surface of the spinning solution is in contact with the atmospheric environment, and the spinning solution may be contaminated with impurities, affecting the uniformity of the subsequent coating of the spinning solution onto the spiral wire electrode. Therefore, in order to solve the problem of residual spinning solution on the spiral electrode, a printing type spiral linear electrospinning nozzle and a use method thereof are designed. SUMMARY

[0004] The present application overcomes the deficiencies of the prior art and provides a printing type spiral linear electrospinning nozzle and a use method thereof.

[0005] To achieve the above object, the technical scheme adopted by the present application is as follows: a printing type spiral linear electrostatic spinning nozzle comprises a nozzle box and a nozzle cover, a metal block in the middle of the nozzle box, and liquid scraping plates fixed symmetrically on both sides of the metal block,

[0006] The top surface of the metal block is provided with a liquid storage groove, and the bottom surface is fixed with the nozzle box, the metal block is provided with a through hole penetrating through the liquid storage groove, the middle part of the liquid scraping plate is provided with a tapered liquid scraping hole in communication with the through hole, and the inside of the tapered liquid scraping hole is provided with a reverse tapered liquid scraping hole, and the both sides of the nozzle box are symmetrically provided with wire passing holes for the spiral electrode to penetrate, and the wire passing holes and the through hole are in communication;

[0007] The bottom parts of the metal block and the nozzle box are both provided with liquid inlet channels, and the liquid inlet channels are threadedly connected with liquid inlet pipes.

[0008] In a preferred embodiment of the present application, the angle between the converging wall surface of the reverse tapered liquid scraping hole and the central axis thereof is 10°-20°.

[0009] In a preferred embodiment of the present application, the inside of the reverse tapered liquid scraping hole is provided with a spiral groove, and the spiral groove is a threaded groove.

[0010] In a preferred embodiment of the present application, the hole diameter of the tapered liquid scraping hole presents a gradually decreasing trend from the side away from the liquid storage groove to the direction of the liquid storage groove, and the hole diameter of the reverse tapered liquid scraping hole presents a gradually increasing trend from the side away from the liquid storage groove to the direction of the liquid storage groove.

[0011] In a preferred embodiment of the present application, the spiral electrode is a threaded rod.

[0012] In a preferred embodiment of the present application, the slot cross section of the spiral groove is semicircular, and the spiral direction of the spiral groove is the same as the spiral direction of the spiral electrode.

[0013] In a preferred embodiment of the present application, the top part of the metal block is provided with a metal cover, and the metal cover is fixedly connected with the metal block through bolts, and one side of the metal cover in contact with the liquid storage groove is provided with a rib protruding, and the rib is sealingly attached to the wall surface of the liquid storage groove.

[0014] In a preferred embodiment of the present application, the wire passing hole penetrates through both ends of the metal block and extends to the outside of the nozzle box, and the axes of the wire passing hole, the tapered liquid scraping hole, the reverse tapered liquid scraping hole and the through hole are located at the same position.

[0015] In a preferred embodiment of the present application, the nozzle cover and the nozzle box are both made of insulating polytetrafluoroethylene material; and the metal block, the metal cover and the liquid inlet channel are all made of stainless steel material.

[0016] A method for using a printed spiral linear electrospinning nozzle, comprising the following steps:

[0017] S1, assemble the electrospinning nozzle to pass through the high-pressure spiral electrode with the liquid scraping hole and the wire passing hole, control the spiral electrode and the axis of the liquid scraping hole to be in the same position;

[0018] S2, input the electrospinning solution into the liquid storage tank through the liquid inlet pipe, and drive the electrospinning nozzle to move left and right on the spiral electrode by the driving device, the liquid scraping plate located in the advancing direction of the electrospinning nozzle can generate vortex by using the reverse conical liquid scraping hole, and the shear force generated by the tangential flow velocity in the vortex can strip the spinning solution from the surface of the thread groove of the spiral electrode.

[0019] The present application solves the defects in the background art, and has the following advantages:

[0020] (1) The present application provides a printed spiral linear electrospinning nozzle and its use method, by setting the reverse conical liquid scraping hole and the spiral groove, the electrospinning nozzle generates spiral vortex during movement, and the spiral vortex is used to perform tangential stripping motion on the spinning solution on the spiral electrode to generate shear force, which strips the spinning solution from the surface of the thread groove at each position of the spiral electrode, avoids the residue of the spinning solution at the pre-coated position of the spiral electrode, and improves the uniformity and purity of the subsequent solution coating, thereby improving the spinning yield.

[0021] (2) The present application controls the pitch of the spiral groove by setting the spiral groove inside the reverse conical liquid scraping hole, improves the tangential velocity component of the spiral groove, increases the velocity gradient of the spinning solution in the reverse conical liquid scraping hole, makes the spiral rotation direction change faster, generates greater friction and shear force, and thereby strips the spinning solution from the surface of the spiral electrode faster.

[0022] (3) The present application keeps the thread rotation direction of the spiral groove consistent with the movement direction of the spiral electrode, the cutting force direction generated by the spiral vortex is consistent with the movement direction of the spiral electrode, the rotational motion of the spinning solution in the spiral vortex is guided by the spiral wall surface of the spiral electrode, generates rotation and pushing force consistent with the movement direction of the spiral electrode, and can maximize the use of the kinetic energy of the spiral electrode to clean the surface.

[0023] (4) The present application generates spiral vortex by the spiral groove inside the reverse conical liquid scraping hole, delays the speed of the spinning solution flowing out of the liquid scraping hole, increases the residence time of the spinning solution in the liquid scraping hole, cooperates with the pressure gradient formed by the spinning solution in the spiral vortex, makes the spinning solution in the spiral vortex have greater power, generates greater shear force, and is beneficial to better stripping and removing the spinning solution attached to the surface of the spiral electrode.

[0024] (5) the present application through the setting of helical groove, the curved streamline in the helical groove increases the time and area of the spinning solution in the helical vortex and the surface contact of the helical electrode, and the existence of pressure gradient further prolongs the time of the spinning solution in the helical vortex and the surface contact of the helical electrode, which is beneficial to more fully remove the spinning solution on the surface of the helical electrode. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0026] Figure 1 is a structural exploded schematic view of the electrospinning nozzle of the preferred embodiment of the present application;

[0027] Figure 2 is a front sectional view of the electrospinning nozzle of the preferred embodiment of the present application;

[0028] Figure 3 is a schematic view of the reverse conical liquid scraping hole and helical groove structure of the preferred embodiment of the present application;

[0029] Figure 4 is a schematic view of the running structure of the electrospinning nozzle equipment of the preferred embodiment of the present application.

[0030] In the figure: 1, nozzle box; 2, nozzle cover; 3, metal block; 4, liquid scraping plate; 5, liquid storage tank; 6, tapered liquid scraping hole; 7, reverse conical liquid scraping hole; 8, liquid inlet pipe; 9, helical groove; 10, helical electrode; 11, metal cover. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0032] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0033] As Figure 1 and Figure 2As shown, it comprises: a nozzle box 1 and a nozzle cover 2, a metal block 3 located in the middle of the nozzle box 1, and a liquid scraping plate 4 symmetrically fixed on both sides of the metal block 3,

[0034] Two sides of the nozzle box 1 are symmetrically provided with wire passing holes for the spiral electrode 10 to pass through, and the wire passing holes are communicated with the through holes; the spiral electrode 10 is provided in the form of a threaded rod;

[0035] The top surface of the metal block 3 is provided with a liquid storage groove 5, and the bottom surface is fixed with the nozzle box 1; the metal block 3 is provided with a through hole penetrating through the liquid storage groove 5; the middle part of the liquid scraping plate 4 is provided with a tapered liquid scraping hole 6 communicated with the through hole; the hole diameter of the tapered liquid scraping hole 6 gradually decreases from the side far away from the liquid storage groove 5 to the direction of the liquid storage groove 5, and the inside of the tapered liquid scraping hole 6 is provided with a reverse tapered liquid scraping hole 7; the hole diameter of the reverse tapered liquid scraping hole 7 gradually increases from the side far away from the liquid storage groove 5 to the direction of the liquid storage groove 5;

[0036] During the movement of the electrostatic spinning nozzle, the position with small hole diameter of the reverse tapered liquid scraping hole 7 will limit the flow of the spinning solution in the reverse tapered liquid scraping hole 7, and increase the flow rate; according to Bernoulli's law, when the flow rate of the fluid increases, the pressure will decrease accordingly;

[0037] Therefore, in the area with small hole diameter, the pressure will decrease, forming a relatively negative pressure area, so that a pressure difference is generated between this area and the area with large hole diameter; the pressure difference will drive the spinning solution to flow to the negative pressure area, so as to ensure that the spinning solution scraped in the reverse tapered liquid scraping hole 7 flows to the position with the smallest hole diameter of the reverse tapered liquid scraping hole 7; with the continuous process, the spinning solution in the reverse tapered liquid scraping hole 7 will enter the tapered liquid scraping hole 6, and will be scraped from the spiral electrode 10.

[0038] As shown in the figure, Figure 3 The inside of the reverse tapered liquid scraping hole 7 is provided with a spiral groove 9, and the spiral groove 9 is provided in the form of a threaded groove, so that during the movement of the nozzle, the spiral groove 9 will generate a spiral vortex, and drive the residual spinning solution on the spiral electrode 10 to rotate and peel off;

[0039] The bottom of the metal block 3 and the nozzle box 1 is provided with a liquid inlet channel, and the liquid inlet channel is threadedly connected with a liquid inlet pipe 8.

[0040] During the use of the electrostatic spinning nozzle, the electrostatic spinning nozzle is sleeved on the spiral electrode 10, the spiral electrode 10 rotates, and the electrostatic spinning nozzle is driven to move on the spiral electrode 10; the reverse tapered liquid scraping hole 7 cooperates with the spiral groove 9 in the inside, and generates a spiral vortex to scrape the residual spinning solution on the spiral electrode 10.

[0041] In a preferred embodiment of the present application, the slot cross section of the spiral groove 9 is semicircular, and the spiral direction of the spiral groove 9 is the same as the spiral direction of the spiral electrode 10;

[0042] The thread rotation direction of the helical groove 9 is consistent with the movement direction of the helical electrode 10, the cutting force direction of the helical eddy current is consistent with the movement direction of the helical electrode 10, the spinning solution in the helical eddy current is guided by the helical wall surface of the helical electrode 10, and rotation and pushing forces consistent with the movement direction of the helical electrode 10 are generated, so that the surface can be cleaned by the maximum utilization of the kinetic energy of the helical electrode 10 itself.

[0043] In a preferred embodiment of the present application, the top of the metal block 3 is provided with a metal cover 11, which is fixedly connected to the metal block 3 through bolts, and the metal cover 11 protrudes from the side in contact with the liquid storage tank 5 and is provided with a rib.

[0044] In a preferred embodiment of the present application, the wire passing hole penetrates through both ends of the metal block 3 and extends to the outside of the nozzle box 1, and the wire passing hole, the tapered liquid scraping hole 6, the reverse tapered liquid scraping hole 7, and the perforated hole are coaxial.

[0045] In a preferred embodiment of the present application, the nozzle cover 2 and the nozzle box 1 are made of insulating polytetrafluoroethylene material; the metal block 3, the metal cover 11, and the liquid inlet channel are made of stainless steel material.

[0046] In a preferred embodiment of the present application, the angle between the contraction wall surface of the reverse tapered liquid scraping hole 7 and the central axis thereof is 10°-20°; changing the reverse tapered liquid scraping hole 7 with different angles between the contraction wall surface and the central axis thereof, the efficiency of extruding the spinning solution in the reverse tapered liquid scraping hole 7 into the tapered liquid scraping hole 6 is different, and the following experiments are performed according to the different angles between the contraction wall surface of the reverse tapered liquid scraping hole 7 and the central axis thereof.

[0047] Five metal blocks in the present scheme are prepared, the reverse tapered liquid scraping holes in each metal block have different contraction angles (10°, 12.5°, 15°, 17.5°, 20°), and are sequentially recorded as samples 1-5; a spiral electrode, five 50g spinning solutions, a driving device, and a thread groove with the same pitch and trapezoidal cross section inside the reverse tapered liquid scraping hole are prepared;

[0048] In example one, a 50g spinning solution is evenly coated on a certain area of the spiral electrode to simulate the state of residual spinning solution on the spiral electrode, the metal block with the angle between the contraction wall surface of the reverse tapered liquid scraping hole and the central axis thereof being 10° is sleeved on the spiral electrode, the driving device is used to drive the metal block to move, and the mass of the spinning solution entering the tapered liquid scraping hole is collected.

[0049] Example two, the operation is basically the same as example one, different is, select the angle of the metal block of the reverse tapered liquid scraping hole shrink wall surface and the central axis is 12.5°, to drive the device to drive the metal block to move, the mass of the spinning solution entering into the tapered liquid scraping hole is collected.

[0050] Example three, the operation is basically the same as example one, different is, select the angle of the metal block of the reverse tapered liquid scraping hole shrink wall surface and the central axis is 15°, to drive the device to drive the metal block to move, the mass of the spinning solution entering into the tapered liquid scraping hole is collected.

[0051] Example four, the operation is basically the same as example one, different is, select the angle of the metal block of the reverse tapered liquid scraping hole shrink wall surface and the central axis is 17.5°, to drive the device to drive the metal block to move, the mass of the spinning solution entering into the tapered liquid scraping hole is collected.

[0052] Example five, the operation is basically the same as example one, different is, select the angle of the metal block of the reverse tapered liquid scraping hole shrink wall surface and the central axis is 20°, to drive the device to drive the metal block to move, the mass of the spinning solution entering into the tapered liquid scraping hole is collected.

[0053] Based on the above examples, at the same time, the rheometer is used to detect the shear force of the spinning solution through the reverse tapered liquid scraping hole, and the flow meter is used to detect the flow of the spinning solution through the reverse tapered liquid scraping hole, which is shown in table 1.

[0054] Table 1

[0055] Mass of collected solution (g) Shear stress (Pa) Flow rate (ml / min) Example 1 20 86.2 36.2 Example 2 28.6 91.1 42.1 Example 3 35.1 97.6 46.5 Example 4 42.3 102.1 51.3 Example 5 40.1 102.9 37.2

[0056] In summary, as the angle of the reverse tapered liquid scraping hole shrink wall surface and the central axis gradually increases, the weight of the solution collected from the tapered liquid scraping hole is larger, the shear force of the liquid scraping position of the reverse tapered liquid scraping hole is gradually increased, mainly because the larger angle means a larger slope, thus generating a greater component force to push the liquid to flow outward, also making the shear force gradually increase, also making the flow of the liquid scraping position of the reverse tapered liquid scraping hole continuously increase, when the angle of the reverse tapered liquid scraping hole shrink wall surface and the central axis is 17.5°, the shear force of the liquid scraping position of the reverse tapered liquid scraping hole and the flow reach the maximum value, the weight of the solution collected from the tapered liquid scraping hole also reaches the maximum value, when the angle of the reverse tapered liquid scraping hole shrink wall surface and the central axis continues to increase, the flow of the liquid scraping position of the reverse tapered liquid scraping hole will decrease, the weight of the solution collected from the tapered liquid scraping hole will also decrease, mainly because the cross-sectional area of the liquid scraping hole at both ends is relatively large, resulting in an increase in the flow resistance of the spinning solution at the liquid scraping position of the reverse tapered liquid scraping hole, and the phenomenon of vortex appears, therefore, in the above examples, example four is the optimal solution of the angle of the reverse tapered liquid scraping hole.

[0057] Considering that the cross-sectional shape of the spiral groove is different, its efficiency for scraping the residual spinning solution on the spiral electrode is different, therefore, the following examples are made for this problem;

[0058] I. Examples:

[0059] (I) Experimental preparation

[0060] Prepare three metal blocks, and the angle between the shrinkage wall surface of the reverse conical liquid scraping hole in the three metal blocks and the central axis is 17.5°, the cross-sectional shape of the spiral groove in the reverse conical liquid scraping hole in the three metal blocks is trapezoidal, semicircular and triangular respectively, and the spiral groove depth is the same, prepare the same specification of spiral electrode, three 50g spinning solutions, and a driving device.

[0061] (II) Experimental steps

[0062] In experimental example one, evenly coat one 50g spinning solution on a certain area of the spiral electrode to simulate the state of the residual spinning solution on the spiral electrode, put the metal block with trapezoidal cross-sectional spiral groove on the spiral electrode, and drive the metal block to move by the driving device. The scraping degree can be evaluated by measuring the three-dimensional morphology of the spiral electrode surface by using an optical profiler.

[0063] In experimental example two, it is basically the same as experimental example one, except that the metal block with semicircular cross-sectional spiral groove is selected to be put on the spiral electrode, and the driving device is used to drive the metal block to move. The scraping degree can be evaluated by measuring the three-dimensional morphology of the spiral electrode surface by using an optical profiler.

[0064] In experimental example three, it is basically the same as experimental example one, except that the metal block with triangular cross-sectional spiral groove is selected to be put on the spiral electrode, and the driving device is used to drive the metal block to move. The scraping degree can be evaluated by measuring the three-dimensional morphology of the spiral electrode surface by using an optical profiler.

[0065] Based on the above experimental examples, the scraping degree of the residual solution on the spiral electrode is obtained as shown in Table 2, wherein the optical profiler uses optical interference technology to obtain detailed profile information of the surface, and the change before and after scraping is compared by computer analysis, which is prior art and will not be described in detail;

[0066] Table 2

[0067] Experimental Example 1 Experimental Example 2 Experimental Example 3 Roughness value / Ra value (μm) 0.85 0.55 0.75

[0068] In summary, the anti-cone-shaped liquid scraping hole with a semi-circular cross-section of the spiral groove has a higher efficiency in scraping the residual spinning solution on the spiral electrode, mainly because of the semi-circular curvature effect, the spinning solution is affected by the centripetal force, so that the movement direction is more inclined to the tangent direction, at the same time, the shape of the semi-circular spiral groove can reduce the flow resistance of the spinning solution in the groove, reduce the energy loss, so as to more effectively convert the momentum of the spinning solution into the tangential velocity component; and the semi-circular shape has symmetry, the spinning solution is uniformly affected by the centripetal force in the spiral groove, which makes the movement trajectory of the spinning solution more stable and controllable.

[0069] It is worth mentioning that because the pitch of the spiral groove is different, the tangential velocity component and the radial velocity component of the spiral groove are different, which drives the spiral angle of the spiral vortex in the anti-cone-shaped liquid scraping hole to be different, cooperates with the thread groove on the spiral electrode, generates shear force, and is used for scraping the residual spinning solution on the spiral electrode to different degrees. Based on this, the following experiment is designed.

[0070] II. Examples:

[0071] (I) Experimental preparation

[0072] a. Prepare four 50g spinning solutions to ensure uniform composition and concentration.

[0073] b. Prepare five identical specifications of threaded rods with a length of 100cm and a diameter of 1cm.

[0074] c. Prepare four moving sleeves with a length, width and height of 3cm. The middle part of the moving sleeve is provided with an anti-cone-shaped hole. The hole diameter of the anti-cone-shaped hole shows a gradual increasing trend from the moving direction of the moving sleeve. The angle between the shrinkage wall surface of the anti-cone-shaped hole and the center axis is 17.5°.

[0075] d. The inner wall of the anti-cone-shaped hole is provided with a spiral groove with a semi-circular cross-section. The length of each spiral groove is 3cm and the specifications are the same.

[0076] e. The pitches of the four spiral grooves are 0.2cm, 0.4cm, 0.6cm and 0.8cm respectively, and are marked as samples 1-5.

[0077] (II) Experimental steps

[0078] In example four, a 50g spinning solution is evenly coated on a certain area of the threaded rod to simulate the state of the residual spinning solution on the spiral electrode. The moving sleeve with a spiral pitch of 0.2cm is sleeved on the threaded rod with an anti-cone-shaped hole to drive the moving sleeve to move towards the smallest hole diameter direction. The optical profilometer can evaluate the scraping degree by measuring the three-dimensional topography of the spiral electrode surface.

[0079] Experimental Example Five is basically the same as Experimental Example Four, except that a moving sleeve with a thread groove of 0.4 cm pitch is selected, a reverse tapered hole is sleeved on the threaded rod, and the moving sleeve is driven by the driving device to move in the direction of its smallest aperture. The degree of scraping can be evaluated by measuring the three-dimensional topography of the surface of the spiral electrode using an optical profilometer.

[0080] Experimental Example Six is basically the same as Experimental Example Four, except that a moving sleeve with a thread groove of 0.6 cm pitch is selected, a reverse tapered hole is sleeved on the threaded rod, and the moving sleeve is driven by the driving device to move in the direction of its smallest aperture. The degree of scraping can be evaluated by measuring the three-dimensional topography of the surface of the spiral electrode using an optical profilometer.

[0081] Experimental Example Seven is basically the same as Experimental Example Four, except that a moving sleeve with a thread groove of 0.8 cm pitch is selected, a reverse tapered hole is sleeved on the threaded rod, and the moving sleeve is driven by the driving device to move in the direction of its smallest aperture. The degree of scraping can be evaluated by measuring the three-dimensional topography of the surface of the spiral electrode using an optical profilometer.

[0082] Based on Experimental Examples Four to Seven described above, by changing the different pitches, the following formula is used:

[0083]

[0084]

[0085] wherein, represents the tangential velocity component, is the angular velocity, is the maximum radius of the thread groove, is the linear velocity, is the pitch.

[0086] Based on the above formula, the relationship between the tangential velocity component and the pitch needs to be derived, using the formula

[0087]

[0088] wherein, represents the circumference of the maximum aperture position;

[0089] Thus, it can be concluded that the pitch size of the thread groove is inversely proportional to its tangential velocity component.

[0090] Table 3

[0091] Roughness value / Ra value (μm) Flow rate (ml / min) Experimental Example 4 0.6 39.5 Experimental Example 5 0.36 51.2 Experimental Example 6 0.45 56.3 Experimental Example 7 0.58 63.5

[0092] In summary, comparing experimental examples four to seven, with the decrease of the pitch, the tangential velocity component increases, and the effect of scraping the residual spinning solution on the threaded rod is better, until the pitch is reduced to 0.4 cm, the scraping degree of the residual spinning solution on the threaded rod reaches the best, and with the further decrease of the pitch, the scraping degree of the residual spinning solution on the threaded rod decreases, mainly because the pitch is too small, increasing the frictional resistance of the spinning solution passing through the threaded groove, hindering the flow of the spinning solution, increasing the instability of the spinning solution flowing in the reverse conical hole, thereby affecting the scraping efficiency; thus, all the experiments above show that experimental example five is the optimal solution of the present application.

[0093] As shown in Figure 4 A method for using a printed spiral linear electrospinning nozzle, comprising the following steps:

[0094] S1, assemble the electrospinning nozzle, and pass the liquid scraping hole and the wire passing hole through the high-voltage spiral electrode, control the spiral electrode and the axis of the liquid scraping hole to be in the same position;

[0095] S2, input the electrospinning solution into the liquid storage tank through the liquid inlet pipe, and drive the electrospinning nozzle to move left and right on the spiral electrode by the driving device, the liquid scraping plate located in the forward direction of the electrospinning nozzle will generate vortex flow by using the reverse conical liquid scraping hole, and the shear force generated by the tangential flow velocity in the vortex flow will strip the spinning solution from the surface of the threaded groove of each position of the spiral electrode.

[0096] The above is based on the ideal embodiment of the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application.

Claims

1. A printing-type spiral linear electrostatic spinning nozzle, comprising: The nozzle box and nozzle cover, a metal block located in the middle of the nozzle box, and wiper blades symmetrically fixed on both sides of the metal block are characterized in that... The top surface of the metal block is provided with a liquid storage tank, and the bottom surface is fixed to the nozzle box. The metal block is provided with a through hole that penetrates the liquid storage tank. The middle part of the scraper is provided with a tapered scraping hole that communicates with the through hole, and the inside of the tapered scraping hole is provided with an inverted conical scraping hole. The two sides of the nozzle box are symmetrically provided with wire feeding holes for the spiral electrode to pass through, and the wire feeding holes and the through hole are connected. Both the metal block and the nozzle box have liquid inlet channels at their bottoms, and liquid inlet pipes are threadedly connected to the liquid inlet channels. The angle between the contraction wall of the reverse conical scraping hole and its central axis is 10° to 20°. The interior of the reverse conical scraping hole is provided with a spiral groove, and the spiral groove is provided with a threaded groove; The groove opening has a semi-circular cross-section, and the spiral direction of the spiral groove is the same as the spiral direction of the spiral electrode.

2. The printing type spiral linear electrostatic spinning nozzle according to claim 1, characterized in that: The diameter of the tapered scraping hole gradually decreases from the side away from the liquid storage tank towards the liquid storage tank, while the diameter of the inverted conical scraping hole gradually increases from the side away from the liquid storage tank towards the liquid storage tank.

3. The printing type spiral linear electrostatic spinning nozzle according to claim 1, characterized in that: The spiral electrode is configured as a threaded rod.

4. The printing type spiral linear electrostatic spinning nozzle according to claim 1, characterized in that: A metal cover is installed on the top of the metal block and is fixedly connected to the metal block by bolts. The side of the metal cover that contacts the liquid storage tank has a protruding ridge, and the ridge is sealed and fitted to the wall of the liquid storage tank.

5. A printing-type spiral linear electrostatic spinning nozzle according to claim 1, characterized in that: The wire feed hole passes through both ends of the metal block and extends to the outside of the nozzle box, and the axes of the wire feed hole, the tapered scraper hole, the reverse conical scraper hole and the perforation are in the same position.

6. A printing-type spiral linear electrostatic spinning nozzle according to claim 1, characterized in that: The nozzle cover and nozzle box are both made of insulating polytetrafluoroethylene; the metal block, metal cover and liquid inlet channel are all made of stainless steel.

7. A method of using a printed spiral linear electrospinning nozzle, comprising using a printed spiral linear electrospinning nozzle according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Assemble the electrostatic spinning nozzle, with the scraping hole and the wire feeding hole fitted onto the high-voltage spiral electrode, and control the axis of the spiral electrode and the scraping hole to be in the same position. S2. The electrospinning solution is fed into the storage tank through the inlet pipe, and the electrospinning nozzle is driven by the drive device to move left and right on the spiral electrode. The scraper located in the forward direction of the electrospinning nozzle will generate vortices using its reverse conical scraping holes. The shearing force generated by the tangential flow velocity in the vortex will peel the spinning solution from the surface of the thread groove at various positions of the spiral electrode.

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