A janus nanofiber electrospinning device

Abstract

The utility model belongs to electrospinning technical field relates to a kind of Janus nanofiber electrospinning device, liquid storage module, including N liquid storage tank, for storing spinning solution;Wherein, N≥2;Spinning module, its top is provided with recess, recess is separately provided with multiple sharp copper bars in, for the recess is divided into N area, each area bottom is provided with the liquid supply passage through recess bottom and spinning module side wall;Liquid supply module, including N liquid supply pump, each liquid supply pump is connected one liquid storage tank and one liquid supply passage by conduit, for the spinning solution in N liquid storage tank is transmitted to the N area in recess by liquid supply passage;High voltage power supply, anode is connected with each sharp copper bar, cathode is connected with receiving module, for forming high voltage electric field between sharp copper bar and receiving module, so that the spinning solution in each area in recess generates jet at the top of sharp copper bar and forms nanofiber.

Description

Technical Field

[0001] This utility model relates to the field of electrospinning technology, and in particular to a Janus nanofiber electrospinning device. Background Technology

[0002] Nanofibers, with their diverse functions and complex structures, are a research hotspot in the field of nanomaterials. Among various techniques for preparing nanofibers, electrospinning technology stands out for its unique advantages, such as its ability to produce nanofibers with extremely fine diameters, huge specific surface areas, and extremely high porosity. It has broad application prospects in multiple fields and has attracted widespread attention.

[0003] Traditional single-needle electrospinning devices consist of a high-voltage power supply, a spinning needle, a solution storage and delivery system, a collection device, and a control system. Under the influence of the high-voltage electric field provided by the power supply, the solution at the tip of the spinning needle overcomes surface tension due to electrostatic force, forming a cone shape. When the electric field exceeds a critical value, a charged solution jet is ejected from the tip of the spinning needle. During its flight, the jet forms nanoscale fibers due to solvent evaporation or solidification and deposits on the collection device, thus completing the spinning process. However, this single-needle device can only produce one jet, yielding only milligram-level fibers per hour. Furthermore, the needle is easily clogged by high-concentration solutions, resulting in low production efficiency. In addition, single-needle devices cannot achieve in-situ composite of multi-component, multi-scale fibers, and can only produce nanofibers of single materials.

[0004] The existing free-surface electrospinning device fundamentally solves the problems of needle clogging and low spinning efficiency in single-needle electrospinning devices. It includes a high-voltage power supply, a free-surface generation system comprising a rotating disk and a vibrating nozzle, a collection device, and a drive system. The rotating disk holds the spinning solution and rotates under the control of the drive system, causing the solution to form a continuous liquid surface at the disk's edge. The vibrating nozzle, under the control of the drive system, mechanically vibrates to create ripples on the liquid surface, thus forming multiple jet initiation points. Each jet independently deposits on the collection device to form fibers, achieving a fiber yield dozens of times higher than that of single-needle electrospinning devices, while also avoiding needle clogging. However, this device is essentially still a single-component continuous spinning process and cannot achieve in-situ composite of multi-component, multi-scale fibers; that is, it cannot prepare Janus nanofibers that require precise spatial differentiation between two or more materials.

[0005] In summary, existing electrospinning equipment cannot efficiently and in large quantities produce Janus nanofibers. Summary of the Invention

[0006] Therefore, the technical problem to be solved by this invention is to overcome the problem that the existing electrospinning devices cannot efficiently and in large quantities prepare Janus nanofibers.

[0007] To solve the above-mentioned technical problems, this utility model provides a Janus nanofiber electrospinning device, characterized in that it includes:

[0008] The liquid storage module includes N liquid storage tanks for storing spinning solution; where N≥2;

[0009] The spinning module has a groove on its top, and multiple pointed copper busbars are set separately in the groove to divide the groove into N regions. Each region has a liquid supply channel at the bottom that connects the bottom of the groove and the side wall of the spinning module.

[0010] The liquid supply module includes N liquid supply pumps. Each liquid supply pump is connected to a liquid storage tank and a liquid supply channel through a conduit. It is used to transfer the spinning solution in the N liquid storage tanks to the N areas in the groove through the liquid supply channel.

[0011] The high-voltage power supply has its positive terminal connected to each of the pointed copper busbars and its negative terminal connected to the receiving module. It is used to create a high-voltage electric field between the pointed copper busbars and the receiving module, so that the spinning solution in each area of ​​the groove can generate a jet at the top of the pointed copper busbar and form nanofibers.

[0012] Preferably, the top of the tip copper busbar is higher than the upper surface of the spinning module.

[0013] Preferably, the height and width of the tip of the copper busbar are both less than or equal to 2 mm.

[0014] Preferably, the receiving module is positioned 12cm to 20cm from the top of the tip copper busbar to receive nanofibers.

[0015] Preferably, each storage tank is equipped with a bladed spiral stirring rotor for stirring the spinning solution.

[0016] Preferably, it further includes: a liquid level detector, which is disposed in each area of ​​the groove to detect the real-time liquid level in each area.

[0017] Preferably, it also includes: a flow sensor, which is installed at the connection between each liquid supply channel and the bottom of the groove, for detecting the real-time liquid supply flow of each liquid supply channel.

[0018] Preferably, the liquid supply channel is provided with an expansion hole at one end near the bottom of the groove.

[0019] Preferably, it further includes a control module connected to the telescopic hole in the spinning module for adjusting the area of ​​the telescopic hole.

[0020] Preferably, when the telescopic hole is a piezoelectric ceramic sheet, the control module adjusts the area of ​​the telescopic hole by changing the voltage of the telescopic hole;

[0021] When the telescopic orifice is a miniature electromagnetic valve, the control module adjusts the area of ​​the telescopic orifice by changing the current in the orifice.

[0022] The above-mentioned technical solution of this utility model has the following advantages compared with the prior art:

[0023] This application divides the grooves in the spinning module into multiple regions. The bottom of each region is connected to multiple liquid storage tanks via liquid supply channels. Multiple liquid supply pumps transfer the spinning solution from each storage tank to the spinning module, achieving spatial partitioned parallel spinning. Different storage tanks can store spinning solutions with different compositions, thus enabling multi-material parallel spinning to prepare Janus nanofibers. Simultaneously, a pointed copper busbar is used to divide the grooves into independent regions, replacing the needles in existing spinning devices. Based on the principle of tip discharge, the spinning solution in each region is adsorbed onto the tip of the copper busbar under the action of a high-voltage electric field, forming a Taylor cone and generating a jet, which is then formed into nanofibers in the receiving module, avoiding the needle clogging problem in existing spinning devices. In addition, since a single pointed copper busbar has multiple tips, jets can be generated simultaneously for spinning, effectively improving spinning efficiency. The Janus nanofiber electrospinning device provided in this application can achieve efficient preparation of Janus nanofibers through spatial partitioned spinning combined with the principle of tip discharge. Attached Figure Description

[0024] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0025] Figure 1 This is a structural diagram of the Janus nanofiber electrospinning device provided in this application;

[0026] Figure 2 A structural diagram of the spinning module of the Janus nanofiber electrospinning apparatus provided in this application;

[0027] Figure 3 A schematic diagram of the pointed copper busbar provided in this application;

[0028] Explanation of reference numerals in the accompanying drawings: 1. Liquid storage module; 11. Liquid storage tank; 2. Spinning module; 21. Groove; 22. Tip copper busbar; 23. Liquid supply channel; 3. Liquid supply module; 31. Liquid supply pump; 32. Conduit; 4. High voltage power supply; 5. Receiving module; 6. Control module. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0030] Please see Figure 1 , Figure 1 The diagram shown is a structural diagram of a Janus nanofiber electrospinning device provided in this application. The device specifically includes: a liquid storage module 1, a spinning module 2, a liquid supply module 3, a high-voltage power supply 4, and a receiving module 5.

[0031] The liquid storage module 1 includes N liquid storage tanks 11 for storing spinning solution; wherein, N≥2.

[0032] It should be noted that when preparing Janus nanofibers, each reservoir 11 is used to store spinning solutions with different properties or materials, thereby enabling the preparation of Janus nanomaterials by partitioning multiple spinning solutions. When preparing nanofibers of a single material, each reservoir 11 can store spinning solutions of the same material. In this case, this partitioned spinning design can also increase the spinning efficiency by N times, while making the thickness and material distribution of the prepared nanofibers more uniform and improving the spinning quality.

[0033] Furthermore, a bladed spiral stirring rotor is installed inside the liquid storage tank 11, which can continuously stir the spinning solution in the liquid storage tank 11 to ensure that the filler is fully mixed and effectively prevent the spinning solution from solidifying.

[0034] The top of the spinning module 2 is provided with a groove 21, and multiple pointed copper busbars 22 are separately provided in the groove 21 to divide the groove 21 into N regions. Each region is provided with a liquid supply channel 23 that runs through the bottom of the groove 21 and the side wall of the spinning module 2.

[0035] Furthermore, in some embodiments of this application, the top of the tip copper busbar 22 is higher than the upper surface of the spinning module 2, thereby ensuring that the spinning liquid in different areas of the groove 21 does not communicate with each other.

[0036] Furthermore, the height and width of the needle tip of the copper busbar 22 are both less than or equal to 2 mm.

[0037] For example, such as Figure 2 The figure shows a structural diagram of the spinning module of a Janus nanofiber electrospinning device with N=2 provided in this application. As can be seen from the figure, the spinning module 2 is a hollow cylindrical insulating material with a groove 21 on the top. The copper busbar 22 at the tip divides the groove 21 into N regions, and each region has a liquid supply channel 23 at the bottom.

[0038] like Figure 3The diagram shows a tip copper busbar. The tip copper busbar 22 can be used to separate the spinning solution in different areas. At the same time, since multiple tips are distributed on the tip copper busbar 22, based on the tip discharge principle, these tips can operate synchronously, that is, jets can be formed at the edges of each tip of the tip copper busbar 22, thereby preparing Janus nanofibers more quickly and efficiently.

[0039] The liquid supply module 3 includes N liquid supply pumps 31. Each liquid supply pump 31 is connected to a liquid storage tank 11 and a liquid supply channel 23 through a conduit 32, and is used to transfer the spinning liquid in the N liquid storage tanks 11 to the N areas in the groove 21 through the liquid supply channel 23.

[0040] The positive terminal of the high-voltage power supply 4 is connected to each of the pointed copper busbars 22, and the negative terminal is connected to the receiving module 5. This is used to form a high-voltage electric field between the pointed copper busbars 22 and the receiving module 5, so that the spinning liquid in each region of the groove 21 generates a jet at the top of the pointed copper busbars 22 and forms nanofibers.

[0041] Existing electrospinning devices use needles as the jet generator. The fine aperture of the needles can easily lead to the deposition of high-viscosity spinning solution or the jamming of solid particles, thus affecting spinning efficiency. This application uses a pointed copper busbar instead of a traditional needle. Since the copper busbar is not a closed channel but an open structure, the spinning solution is adsorbed on the tip of the copper busbar by liquid surface tension to form a jet, thereby avoiding the channel blockage problem during the spinning process.

[0042] Specifically, based on the principle of tip discharge, this application uses a copper busbar with a tip to replace the metal column or air bubble in the traditional free liquid surface electrospinning device. At the same time, the tip copper busbar divides the groove in the spinning module into multiple regions. By adding different fillers or polymers to the spinning solution in different regions, Janus nanofibers are endowed with differentiated functions or achieve significant differences in their properties. In addition, thanks to the multiple tips on the tip copper busbar, multiple tips can operate synchronously during the preparation of nanofibers to form jet streams at the same time, thereby efficiently preparing nanofibers.

[0043] Furthermore, the receiving module 5 is positioned 12cm to 20cm away from the top of the tip copper busbar 22 to receive nanofibers.

[0044] Furthermore, in some embodiments of this application, liquid level detectors are provided in various regions within the groove 21 of the spinning module 2 to detect the real-time liquid level in each region.

[0045] Furthermore, in some embodiments of this application, a flow sensor can be provided at the connection between each liquid supply channel 23 and the bottom of the groove 21 to detect the real-time liquid supply flow of each liquid supply channel 23.

[0046] Optionally, in order to better control the liquid supply flow rate of each liquid supply channel 23, in some embodiments of this application, a telescopic hole is provided at one end of the liquid supply channel 23 near the bottom of the groove. The telescopic hole can be a piezoelectric ceramic sheet or a micro electromagnetic valve. By changing the area of ​​the telescopic hole, the liquid supply flow rate of the liquid supply channel 23 can be changed, thereby indirectly changing the spinning liquid level height in different areas of the groove 21, so as to achieve real-time matching of liquid supply and spinning. This can not only adjust the spinning efficiency, but also control the volume ratio of spinning liquid of different materials in the composite fiber, thereby improving the spinning quality.

[0047] Furthermore, the device also includes a control module 6, which is connected to the telescopic hole in the spinning module 2, for adjusting the area of ​​the telescopic hole.

[0048] Specifically, when the telescopic hole is a piezoelectric ceramic sheet, the control module 6 adjusts the area of ​​the telescopic hole by changing the voltage of the telescopic hole; when the telescopic hole is a miniature electromagnetic valve, the control module 6 adjusts the area of ​​the telescopic hole by changing the current of the telescopic hole.

[0049] Optionally, in some embodiments, the liquid level in each area can be detected in real time by a liquid level detector, and the real-time liquid supply flow rate of each liquid supply channel 23 can be detected by a flow sensor. Based on the liquid level and the liquid supply flow rate, it can be determined whether the area of ​​each expansion hole needs to be increased or decreased, thereby changing the liquid level of the spinning solution in different areas.

[0050] In some embodiments, a relationship function between the liquid supply flow rate of the liquid supply channel 23 and the area of ​​the expansion orifice can be constructed, along with an equation for the change in spinning liquid volume corresponding to the change in liquid level in each region of the groove 21. Then, the real-time liquid level and target liquid level in each region of the groove 21 are substituted into the equation for the change in spinning liquid volume to obtain the target liquid supply flow rate of the liquid supply channel 23 in each region. The target liquid supply flow rate of the liquid supply channel 23 in each region is substituted into the relationship function to obtain the target area of ​​the expansion orifice on the liquid supply channel 23 in each region. Thus, the control module 6 outputs control commands to the expansion orifices on each liquid supply channel 23 in the spinning module 2, thereby adjusting the area of ​​each expansion orifice to be equal to the target area.

[0051] Furthermore, the real-time liquid supply flow rate of each liquid supply channel 23 after adjustment can be compared with its target liquid supply flow rate. If the real-time liquid supply flow rate is less than the target liquid supply flow rate, the area of ​​the expansion hole on each liquid supply channel 23 can be increased by the control module 6; if the real-time liquid supply flow rate is greater than the target liquid supply flow rate, the area of ​​the expansion hole on each liquid supply channel 23 can be decreased by the control module 6.

[0052] Specifically, the relationship between the size of the expansion orifice and the liquid supply flow rate of the liquid supply channel 23 is as follows: ,in, Indicates the liquid supply flow rate of the liquid supply channel; , All are constants; This indicates the area of ​​the expansion joint.

[0053] Secondly, for each region within the groove 21 with a sphere radius of R, the cross-sectional area at a liquid level height of h (the vertical distance from the bottom of the groove 21 upwards) is expressed as: .

[0054] Within the time interval dt, the input spinning solution volume is Qdt, which will cause a change in the liquid level height dh within this region. Based on the relationship of the spinning solution volume change within this region: Then Substituting, we can obtain .

[0055] Furthermore, integrating both sides of the above equation, we get:

[0056] ,

[0057] in, Indicates the initial liquid level height;

[0058] Based on the above derivation, we can obtain: .

[0059] In practical applications, the change in spinning solution volume when the current liquid level reaches the target liquid level can be calculated based on the real-time liquid level height in each area and the preset target liquid level height.

[0060] ,

[0061] in, This indicates the change in the volume of the spinning solution; This represents the radius of the sphere from which the groove is cut; Indicates the change in altitude; Indicates the target liquid level height; This indicates the real-time liquid level.

[0062] The flow rate of each supply channel 23 can be calculated based on the change in spinning solution volume and the time it takes for the current liquid level to reach the target liquid level. Thus, the area of ​​the expansion orifice can be obtained based on the relationship between the size of the expansion orifice and the flow rate of the supply channel 23.

[0063] By setting an expansion hole at the connection between the liquid supply channel 23 and the groove 21, the area of ​​the expansion hole can be adjusted in real time based on the liquid level height and target liquid level height in each area of ​​the groove 21 to change the liquid supply flow rate of the liquid supply channel 23, thereby indirectly controlling the liquid level height in each area. When preparing Janus nanofibers by in-situ composite of multi-component and multi-scale fibers, the concentration control of different materials and components during the preparation process can be achieved by individually controlling the size of the expansion hole on the liquid supply channel 23 of each area.

[0064] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A Janus nanofiber electrospinning device, characterized in that, include: The liquid storage module includes N liquid storage tanks for storing spinning solution; where N≥2; The spinning module has a groove on its top, and multiple pointed copper busbars are set separately in the groove to divide the groove into N regions. Each region has a liquid supply channel at the bottom that connects the bottom of the groove and the side wall of the spinning module. The liquid supply module includes N liquid supply pumps. Each liquid supply pump is connected to a liquid storage tank and a liquid supply channel through a conduit. It is used to transfer the spinning solution in the N liquid storage tanks to the N areas in the groove through the liquid supply channel. The high-voltage power supply has its positive terminal connected to each of the pointed copper busbars and its negative terminal connected to the receiving module. It is used to create a high-voltage electric field between the pointed copper busbars and the receiving module, so that the spinning solution in each area of ​​the groove can generate a jet at the top of the pointed copper busbar and form nanofibers.

2. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, The top of the tipped copper busbar is higher than the upper surface of the spinning module.

3. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, The height and width of the needle tip of the copper busbar are both less than or equal to 2 mm.

4. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, The receiving module is positioned 12cm to 20cm from the top of the tip copper busbar and is used to receive nanofibers.

5. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, Each storage tank is equipped with a bladed spiral stirring rotor for stirring the spinning solution.

6. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, Also includes: Liquid level detectors are installed in various areas within the groove to detect the real-time liquid level in each area.

7. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, Also includes: A flow sensor is installed at the connection between each liquid supply channel and the bottom of the groove to detect the real-time liquid supply flow rate of each liquid supply channel.

8. The Janus nanofiber electrospinning apparatus according to claim 1, characterized in that, An expansion joint is provided at one end of the liquid supply channel near the bottom of the groove.

9. The Janus nanofiber electrospinning apparatus according to claim 8, characterized in that, Also includes: The control module is connected to the telescopic hole in the spinning module and is used to adjust the area of ​​the telescopic hole.

10. The Janus nanofiber electrospinning apparatus according to claim 9, characterized in that, When the telescopic hole is a piezoelectric ceramic sheet, the control module adjusts the area of ​​the telescopic hole by changing the voltage of the telescopic hole; When the telescopic orifice is a miniature electromagnetic valve, the control module adjusts the area of ​​the telescopic orifice by changing the current in the orifice.

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