Receiving device for electrostatic spinning equipment and electrostatic spinning equipment

Abstract

The utility model relates to a receiving device for electrostatic spinning equipment and the electrostatic spinning equipment, and the receiving device for the electrostatic spinning equipment comprises a receiving part, which is provided with a receiving surface for fiber deposition; the receiving device is characterized in that a plurality of through holes penetrating through the wall thickness of the receiving face are formed in the receiving face, the receiving piece is provided with a containing cavity communicated with fluid of the through holes, and the receiving device further comprises a negative pressure generating device used for generating negative pressure in the containing cavity. Compared with the prior art, the receiving device has the advantages that the receiving device adopts the Coanda effect, negative pressure is generated in the containing cavity, certain negative pressure is also generated in the through holes in the receiving face, the collection amount of nanofibers is remarkably increased, and therefore the productivity is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electrospinning, in particular to a receiving device for an electrospinning device and an electrospinning device. Background Technique

[0002] At present, there are many methods for preparing nanofibers, such as stretching method, template synthesis method, phase separation method, electrospinning method, etc. The first three methods are still at the laboratory level due to poor process controllability; the electrospinning technology has attracted more and more researchers' attention because of its low cost, simple process, and wide range of polymers that can be spun.

[0003] Traditional needle electrospinning mainly consists of a nozzle, a high-voltage generator and a receiving device. Under the condition of an externally applied high-voltage electric field, a polymer solution forms a hanging conical droplet at the end of the nozzle. When the charge repulsion force on the droplet surface exceeds its surface tension, the droplet sprays out at high speed to form a jet. The jet is further stretched to form nanofibers and finally deposited on the receiving device. With the development of technology, due to the limitation of production capacity in needle electrospinning, and at the same time, because the needle diameter is small, the polymer solution is prone to solidification due to solvent volatilization and water absorption during long-term electrospinning, resulting in needle blockage, which is not conducive to long-term stable production; the needleless nozzle has many excitation points, high production capacity, is not easy to be blocked, and is relatively convenient to clean after use, and is very suitable for batch production.

[0004] Industrial electrospinning equipment mainly generates nanofibers by exciting an industrial nozzle. At present, the relatively common one is a wire electrode. A non-woven fabric that can be automatically wound is used as a receiving device to collect nanofibers. The thickness of the nanofibers is controlled by adjusting the winding speed. At the same time, the production of nanofibers in different systems (such as PAN, PVDF, PU, etc.) can be realized to meet different application requirements. However, in the actual production process, the nanofibers are very light and are easily interfered by the surrounding air flow and are not easily collected by the non-woven fabric, resulting in a reduction in the output of nanofibers. Therefore, it is necessary to improve the existing technology. Summary of the Utility Model

[0005] The first technical problem to be solved by the utility model is to provide a receiving device for an electrospinning device that can facilitate collection to improve the output of nanofibers in view of the above-mentioned prior art.

[0006] The second technical problem to be solved by the utility model is to provide an electrospinning device applying the above receiving device.

[0007] The technical solution adopted by the utility model to solve the above first technical problem is: a receiving device for an electrospinning device, comprising:

[0008] A receiving member having a receiving surface for fiber deposition;

[0009] It is characterized in that: a plurality of through holes penetrating through its wall thickness are provided on the receiving surface, the receiving member has a cavity fluidly connected to the through holes, and the receiving device further includes a negative pressure generating device for generating a negative pressure in the cavity.

[0010] Preferably, the interior of the receiving member is hollow to form the above-mentioned cavity, the cavity has an air inlet and an air outlet, and along the fluid flow path, the receiving surface is provided between the air inlet and the air outlet of the cavity. This can cause an air flow to be generated between the air inlet and the air outlet in the cavity, and further enable a certain negative pressure to be generated in the through holes on the receiving surface when the air flow passes through.

[0011] To make the structure simpler, the receiving surface is one of the outer cavity walls of the cavity.

[0012] In order to generate a greater negative pressure in the through holes on the receiving surface to collect more fibers, the receiving member is provided with a plurality of intake pipes arranged side by side at intervals, and the inlets of each intake pipe form the above-mentioned air inlet. Since the smaller aperture of the intake pipe is conducive to the amplification of the air flow velocity, a greater negative pressure can be generated.

[0013] Preferably, the negative pressure generating device is a fan system, the fan system is located downstream of the air outlet of the cavity, and the air inlet of the fan system is fluidly connected to the cavity.

[0014] Preferably, the receiving member has an arc section, the arc section is inclined in a direction away from the receiving surface along the air flow direction, and the outlet of the arc section forms the above-mentioned air outlet. By providing the arc section, the outflow direction of the air flow can be changed.

[0015] Preferably, the receiving member further includes a straight section connected to the arc section, the straight section extends along the air flow direction, one end of the straight section away from the arc section has the above-mentioned air inlet, and the receiving surface is the wall surface of the straight section away from the air outlet.

[0016] Considering that there will be static electricity during the electrospinning process, preferably, the receiving member is made of an insulating material.

[0017] The technical solution adopted by the present utility model to solve the above-mentioned second technical problem is: an electrospinning device, characterized in that: the above-mentioned receiving device is applied.

[0018] Compared with the prior art, the advantages of the present utility model are: this receiving device uses the Coanda effect to generate a negative pressure in the cavity, so that a certain negative pressure is also generated in the through holes on the receiving surface, and then the collection amount of nanofibers is significantly increased, thereby improving the production capacity. Description of the Drawings

[0019] Figure 1 The structural schematic diagram of the electrospinning device in the embodiment of the present utility model;

[0020] Figure 2 is Figure 1 the structural schematic diagram of the receiving device in;

[0021] Figure 3 is Figure 2 the sectional view of the receiving device in. Specific embodiments

[0022] The following further describes the present utility model in detail with reference to the accompanying drawings and embodiments.

[0023] As Figure 1 shown, the electrospinning device in this embodiment includes a frame 3, a nozzle 4 disposed on the frame 3, and a receiving device disposed above the frame 3. The nozzle 4 faces the receiving device, Figure 1 Although the specific installation structure of the receiving device in is not shown, in fact, it can be assembled above the nozzle 4 by means of a bracket, or directly assembled on the top of the frame 3; specifically, the nozzle 4 includes a mounting seat 41, an electrode wire 42, and a coating device 43. There are two mounting seats 41, which are spaced apart on the left and right sides of the frame 3; the electrode wire 42 is fixed on the two mounting seats 41, and the coating device 43 is slidably disposed on the electrode wire 42. The specific structural design of this nozzle 4 can refer to the needleless electrospinning device in the prior art, or can refer to the content disclosed in the patent with the patent number 202220591682.8 and the patent name of an electrospinning device applied by the applicant first. The working process of this nozzle 4 will not be elaborated here.

[0024] As Figures 1 to 3 shown, the receiving device includes a receiving member 1. The receiving member 1 has a receiving surface 11 for fiber deposition. A plurality of through holes 10 penetrating through its wall thickness are formed on the receiving surface 11. The receiving member 1 has a cavity 12 in fluid communication with the through holes 10. The receiving device 4 further includes a negative pressure generating device for generating negative pressure in the cavity 12. In this embodiment, the receiving member 1 is made of an insulating material, and preferably made of polytetrafluoroethylene material. In addition, the diameter of each through hole 10 on the receiving surface 11 is 3 mm, and the distance between the centers of two adjacent through holes is 6 mm. The through holes 10 on the receiving surface 11 are uniformly arranged along the width direction and the length direction of the receiving surface 11. The design of the entire receiving device can well improve the ability of the non-woven fabric to receive nanofibers.

[0025] As Figure 3As shown in the figure, the receiving member 1 in this embodiment is hollow inside to form the above-mentioned cavity 12. The cavity 12 has an air inlet 12a and an air outlet 12b. Along the fluid flow path, the receiving surface 11 is provided between the air inlet 12a and the air outlet 12b of the cavity 12. As Figure 2 shown, the receiving surface 11 is one of the outer cavity walls of the cavity 12.

[0026] The receiving member 1 has a straight segment 1b and an arc segment 1a connected to the straight segment 1b. The straight segment 1b extends along the air flow direction. One end of the straight segment 1b away from the arc segment 1a has the above-mentioned air inlet 12a. The receiving surface 11 is the wall surface on the straight segment 1b away from the air outlet 12b; the arc segment 1a is inclined in the direction away from the receiving surface 11 along the air flow direction, and the outlet of the arc segment 1a forms the above-mentioned air outlet 12b.

[0027] In addition, as Figure 1 shown, the receiving member 1 is provided with a plurality of intake pipes 2 arranged side by side at intervals. The inlets of the respective intake pipes 2 form the above-mentioned air inlet 12a. In this embodiment, the outer diameter of each intake pipe 2 is 10 mm, the wall thickness is 2 mm, the distance between the two cylinders is 50 mm, and the number of intake pipes is determined according to the width of the receiving device. The smaller aperture is beneficial to the amplification of the air flow velocity, thereby causing a greater negative pressure in the through holes of the receiving surface 11 and realizing more collection of nanofibers.

[0028] In this embodiment, the negative pressure generating device is a fan system (not shown in the figure). The fan system is located downstream of the air outlet 12b of the cavity 12, and the air inlet of the fan system is in fluid communication with the cavity 12.

[0029] To verify the effect of the electrospinning device of the present utility model, four electrode wires are used for electrospinning in this embodiment, and a PET non-woven fabric is used as the receiving substrate. Before electrospinning, the gram weight (g / m 2 ) of the non-woven fabric is weighed with a precision balance. After electrospinning, the total gram weight (g / m 2 ) of the non-woven fabric and the nanofibers is weighed. The latter minus the former gives the gram weight (g / m 2 ) of the nanofibers. During the whole process, the electrospinning voltage, the liquid supply speed, the receiving distance, and the non-woven fabric winding speed are all kept consistent, and the nanofiber yield is converted into g / m 2 / h as the unit according to the non-woven fabric winding speed.

[0030] Experiment 1:

[0031] Solution preparation: Dissolve 180 g of polyurethane pellets in 820 g of N,N-dimethylacetamide, and rapidly stir it in a water bath environment at 60 °C for 6 h. After completion, cool it for standby;

[0032] Electrospinning: Electrospinning is carried out using a conventional wire electrode. The receiving substrate is a non-woven fabric. The spinning voltage is 60 KV, the distance between the substrate and the wire electrode is 28 cm. A coating device is used to supply liquid to its surface. The liquid supply speed of each electrode wire is 30 ml / h, and the winding speed of the non-woven fabric is 0.1 m / min. After electrospinning, the output is calculated, and the output is 30 g / m 2 / h;

[0033] Experiment Two:

[0034] Solution preparation: 180 g of polyurethane pellets are dissolved in 820 g of N, N-dimethylacetamide, and it is rapidly stirred in a water bath environment at 60 °C for 6 h. After completion, it is cooled for standby;

[0035] Electrospinning: The electrospinning equipment assembled with the receiving device in the present utility model is used. The non-woven fabric is still used as the receiving substrate. The air inlet wind speed is 20 m / s, the spinning voltage is 60 KV, the distance between the substrate and the wire electrode is 28 cm. A coating device is used to supply liquid to its surface. The liquid supply speed of each electrode wire is 30 ml / h, and the winding speed of the non-woven fabric is 0.1 m / min. After electrospinning, the output is calculated, and the output is 52 g / m 2 / h;

[0036] It can be seen from the results of the above two experiments that compared with the traditional wire electrode electrospinning device, when electrospinning is carried out using the receiving device in the present utility model, the collection amount of nanofibers is significantly increased, resulting in an increase in output. This is because the negative pressure promotes the collection of nanofibers. At the same time, the electrospinning equipment in this embodiment is also suitable for electrospinning of various polymers; in addition, the organic solvent vapor in the spinning chamber can also flow out along with the airflow in the cavity, reducing the corrosion of the electrospinning equipment by the organic solvent vapor.

[0037] As used in this utility model, "fluid communication" refers to the spatial position relationship between two components or parts (hereinafter uniformly referred to as the first part and the second part respectively), that is, a fluid (gas, liquid or a mixture of both) can flow or / and be transported from the first part along a flow path to the second part. It can be that the first part and the second part are directly connected, or the first part and the second part are indirectly connected through at least one third party. The third party can be a fluid channel such as a pipe, a passage, a conduit, a flow guide, a hole, a groove, etc., or a chamber allowing the fluid to flow through or a combination of the above.

Claims

1. A receiving device for an electrospinning device, comprising: A receiving member (1) having a receiving surface (11) for depositing fibers; The invention is characterized in that: the receiving surface (11) is provided with a plurality of through holes (10) penetrating the wall thickness thereof; the receiving member (1) has a cavity (12) fluidically connected to the through holes (10); and the receiving device (4) further comprises a negative pressure generating device for generating negative pressure in the cavity (12).

2. The receiving device according to claim 1, characterized in that: The receiving member (1) is hollow inside to form the above-mentioned cavity (12), and the cavity (12) has an air inlet (12a) and an air outlet (12b). Along the fluid flow path, the receiving surface (11) is arranged between the air inlet (12a) and the air outlet (12b) of the cavity (12).

3. The receiving device according to claim 2, characterized in that: The receiving surface (11) is one of the outer cavity walls of the containing cavity (12).

4. The receiving device according to claim 3, characterized in that: The receiving member (1) is provided with a plurality of air inlet pipes (2) arranged side by side and spaced apart from each other, and the inlet of each air inlet pipe (2) forms the above-mentioned air inlet port (12a).

5. The receiving device according to claim 2, characterized in that: The negative pressure generating device is a fan system, the fan system is located downstream of the air outlet (12b) of the cavity (12), and the air inlet of the fan system is in fluid communication with the cavity (12).

6. The receiving device according to claim 5, characterized in that: The receiving member (1) has an arc segment (1a), and the arc segment (1a) is inclined along the air flow direction in a direction away from the receiving surface (11), and the outlet of the arc segment (1a) forms the above-mentioned air outlet (12b).

7. The receiving device according to claim 6, characterized in that: The receiving member (1) further comprises a straight segment (1b) connected to the arc segment (1a), the straight segment (1b) extending along the airflow direction, the end of the straight segment (1b) away from the arc segment (1a) having the above-mentioned air inlet (12a), and the receiving surface (11) being a wall surface on the straight segment (1b) away from the air outlet (12b).

8. The receiving device according to any one of claims 1 to 7, characterized in that: The receiving element (1) is made of insulating material.

9. An electrospinning device, characterized in that: A receiving device as described in any one of claims 1 to 8 is used.

Images