Hot air flow assisted slit type bubble electrostatic spinning device

Abstract

The invention provides a slit type bubble electrostatic spinning device assisted by hot air flow. The slit type bubble electrostatic spinning device comprises a hot air flow channel, a slit type metal solution channel, a bubble pipe and an electrostatic generator. The hot air flow channel and the slit type metal solution channel are circular truncated cone-shaped pipelines formed by gradually narrowing inner and outer pipes; the pipe diameter of an inner pipe of the hot air flow channel is the same as that of an outer pipe of the slit type metal solution channel; the slit type metal solution channel penetrates through the inner pipe of the hot air flow channel and is fixedly attached to the inner pipe of the hot air flow channel, the bubble pipe extends and is fixed to the inner pipe of the slit type metal solution channel, and the electrostatic generator is connected with the slit type metal solution guide pipe through a wire. The arrangement of polymer molecular chains in the solution is improved through the slit type metal solution channel, high-speed hot airflow is provided by the circular-truncated-cone-shaped hot airflow channel to upwards support bubbles from the periphery and assist the polymer molecular chains to be evenly distributed in parallel with the surfaces of the bubbles, and the enhanced nanofibers are prepared by improving the internal structure of the nanofibers.

Description

Technical Field

[0001] The invention relates to the technical field of spinning devices, in particular to a hot air flow-assisted slit-type bubble electrostatic spinning device. Background Art

[0002] The design and preparation of enhanced nanofibers are of great significance for the research and development and application of new materials. Natural spider silk, known as "biological steel", has high specific strength, excellent elasticity, toughness and elongation at break, which is unmatched by other fibers, but its cannibalistic nature makes it impossible to achieve commercial production. Therefore, enhanced nanofibers are one of the research hotspots of artificial new fiber materials.

[0003] At present, the electrospinning nozzles for producing nanofibers are mainly divided into multi-needle type and needleless type according to their morphology. Although multi-needle electrospinning can increase the output of nanofibers to a certain extent, there are problems such as mutual interference of electric fields between needles and easy clogging and difficulty in cleaning of needles. Therefore, needleless electrospinning has gradually become a hot topic in research. Bubble electrospinning is a type of needleless electrospinning. This method forms bubbles by injecting air into a polymer solution. When the bubbles burst, a large number of thin fragments will be formed. These thin fragments will be stretched under the action of external forces such as electrostatic force and gravity, and finally made into nanofibers. This method effectively improves the production efficiency of nanofibers and overcomes the inherent shortcomings of multi-needle electrospinning. At present, research on electrospinning nanofibers at home and abroad focuses on the development of functionality and the influence of process parameters on products. Few studies start from the basic principles of mechanics to explore the influence of the internal structure of nanofibers on the mechanical properties of products.

[0004] In view of the above technical problems, how to make the polymer chain molecular chains of bubbles uniformly oriented in bubble electrospinning is one of the most important issues in the preparation of reinforced nanofibers. Summary of the invention

[0005] 1. Technical issues to be solved

[0006] In view of the deficiencies in the prior art, the present invention provides a hot air flow-assisted slit-type bubble electrospinning device, which solves the problems raised in the above-mentioned background technology.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] According to a first aspect of the present invention, there is provided a hot air flow assisted slit bubble electrospinning device, comprising a hot air flow channel, a slit metal solution channel, a bubble tube and an electrostatic generator;

[0010] The hot air flow channel and the slit metal solution channel are both truncated cone-shaped pipes formed by gradually narrowing inner and outer tubes; the inner tube diameter of the hot air flow channel is the same as the outer tube diameter of the slit metal solution channel; the slit metal solution channel penetrates the inner tube of the hot air flow channel and is fitted and fixed to the inner tube of the hot air flow channel, the bubble tube extends and is fixed to the inner tube of the slit metal solution channel, and the electrostatic generator is connected to the slit metal solution conduit through a wire.

[0011] Preferably, the hot air flow channel is connected to the hot air flow compressor through a hot air flow conduit, the maximum distance between the inner tube and the outer tube of the hot air flow channel is ≤10 cm, and the elevation angle between the hot air flow channel and the horizontal plane is 0 to 90°.

[0012] Preferably, the top of the hot air flow channel is lower than the top of the slit-type metal solution channel, and the distance between the top of the hot air flow channel and the top of the slit-type metal solution channel is ≤10 cm.

[0013] Preferably, the portion of the slit-type metal solution channel that is not attached to the hot air flow channel is a cylindrical hollow channel structure, the cylindrical hollow channel of the slit-type metal solution channel is connected to a push rod, and the pusher of the push rod abuts against the cylindrical hollow channel of the slit-type metal solution channel.

[0014] Preferably, the bottom end of the slit-type metal solution channel is connected to a truncated cone container, and the truncated cone container is connected to a syringe pump.

[0015] Preferably, the maximum channel width of the slit-type metal solution channel is ≤5 cm.

[0016] Preferably, the material of the slit-type metal solution channel is a conductive material;

[0017] The material of the hot air flow channel is insulating material.

[0018] Preferably, the bubble tube is connected to the air compressor via an air duct, the top of the bubble tube is lower than the top of the slit metal solution channel, and the distance difference between the top of the bubble tube and the top of the slit metal solution channel is ≤10 cm.

[0019] Preferably, the positive electrode of the electrostatic generator is connected to the metal solution conduit through a wire, and the negative electrode of the electrostatic generator is connected to a spinning receiving plate through a wire, and the spinning receiving plate is located in the direction of the nanofibers ejected by the jet formed by static electricity in the slit-type metal solution channel.

[0020] Preferably, 4 to 8 air inlets are provided at the lower end of the hot air flow channel.

[0021] (III) Beneficial effects

[0022] The present invention provides a hot air flow-assisted slit-type bubble electrospinning device, which has the following beneficial effects:

[0023] The present invention provides a hot air flow-assisted slit bubble electrospinning device. Starting from the basic principles of mechanics, the slit metal solution channel, the gradually narrowing hot air flow channel and the bubble spinning technology are combined by imitating spider silk threads to improve the spinneret. The slit metal solution channel is used to improve the arrangement of polymer molecular chains in the solution, and the truncated cone-shaped hot air flow channel is used to provide high-speed hot air flow to lift the bubbles upward from all sides and help the polymer molecular chains to be evenly distributed parallel to the bubble surface. The internal structure of the nanofibers is improved to prepare enhanced nanofibers. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A hot air flow assisted slit bubble electrospinning device provided in Example 1 of the present invention;

[0025] Figure 2 A hot air flow assisted slit bubble electrospinning device provided in Example 2 of the present invention;

[0026] Figure 3 A hot air flow assisted slit bubble electrospinning device provided in Example 3 of the present invention;

[0027] Figure 4 This is a distribution diagram of the external airflow channels on the bottom surface of the hot airflow channel in Example 1 of the present invention;

[0028] Figure 5 A distribution diagram of external airflow channels on the bottom surface of a hot airflow channel in a hot airflow-assisted slit-bubble electrospinning device provided in Example 4 of the present invention;

[0029] Among them, 1. hot air flow channel; 2. slit metal solution channel; 3. bubble tube; 4. electrostatic generator; 5. wire; 6. hot air flow duct; 7. hot air flow compressor; 8. push rod; 9. propeller; 10. truncated cone container; 11. injection pump; 12. air duct; 13. air compressor; 14. spinning receiving plate; 15. bubbles. DETAILED DESCRIPTION

[0030] In order to better illustrate the content of the present invention, a detailed description is given below in conjunction with specific embodiments.

[0031] Example 1

[0032] A hot air flow assisted slit bubble electrospinning device, such as Figure 1As shown, it includes a hot air flow channel 1, a slit metal solution channel 2, a bubble tube 3 and an electrostatic generator 4, wherein the hot air flow channel and the slit metal solution channel 2 are both truncated cone-shaped pipes formed by gradually narrowing inner and outer tubes, the inner tube diameter of the hot air flow channel 1 is the same as the outer tube diameter of the slit metal solution channel 2, the inner tube of the slit metal solution channel 2 is a cylinder with equal diameters at the top and bottom, the slit metal solution channel 2 passes through the inner tube of the hot air flow channel 1 and is fixed to the inner tube of the hot air flow channel 1, the bubble tube 3 extends and is fixed to the inner tube of the slit metal solution channel 2, the electrostatic generator 4 is connected to the slit metal solution channel 2 through a wire 5, the hot air flow channel 1 is connected to the hot air flow compressor 7 through a hot air flow conduit 6, the maximum distance between the inner tube and the outer tube of the hot air flow channel 1 is 10 cm, the elevation angle between the hot air flow channel 1 and the horizontal plane is 85°, and the hot The top of the airflow channel 1 is lower than the top of the slit metal solution channel 2, and the distance between the top of the hot airflow channel 1 and the top of the slit metal solution channel 2 is 0 cm. In this embodiment, the part of the slit metal solution channel 2 that is not attached to the hot airflow channel 1 is also a cylindrical hollow structure. The cylindrical hollow channel of the slit metal solution channel 2 is connected to the push rod 8, and the propeller 9 of the push rod 8 abuts against the slit metal solution channel 2, so that the propeller 9 pumps the solution to the nozzle at the top of the slit metal solution channel 2 through the push rod 8. The maximum channel width of the slit metal solution channel 2 is 5 cm, and the material of the slit metal solution channel 2 is a conductive material. The specific conductive material can be selected from at least one of copper, aluminum, platinum, silver, iron, nickel, chromium, and manganese. In this embodiment, copper is selected. The material of the hot airflow channel 1 is an insulating material. In this embodiment, plastic is selected, such as Figure 4 As shown, four air inlets are provided at the bottom end of the hot air flow channel 1, and four hot air flow conduits 6 are respectively connected to the four air inlets of the hot air flow channel 1. The bubble tube 3 is connected to the air compressor 13 through the air conduit 12. The top of the bubble tube 3 is lower than the top of the slit metal solution channel 2, and the distance between the top of the bubble tube 3 and the top of the slit metal solution channel 2 is 0 cm. The positive electrode of the electrostatic generator 4 is connected to the slit metal solution channel 2 through the wire 5, and the negative electrode of the electrostatic generator 4 is connected to the spinning receiving plate 14 through the wire 5. The spinning receiving plate 14 is located in the direction of the nanofiber ejected by the jet formed by static electricity from the slit metal solution channel 2.

[0033] During the flow of the solution, the speed in the middle of the slit is the largest. As the solution flows in the slit, the arrangement of the polymer molecular chains becomes more and more orderly. Then, the solution generates bubbles 15 through the airflow at the outlet of the bubble tube 3. The size of the bubbles 15 is controlled by adjusting the size of the airflow. The electrostatic generator 4 applies high pressure to the slit-type metal solution channel 2. At the same time, the hot air compressor 7 releases hot air to the hot air channel 1 through the hot air conduit 6. The hot air is accelerated through the gradually narrowing hot air channel 1 to lift the bubbles 15 at an elevation angle. With the help of the hot air flow, the polymer molecular chains of the bubbles 15 are parallel to the bubbles 15 to avoid uniform arrangement. After the bubbles 15 are broken, a large number of thin fragments are formed, which form nanofibers under the combined action of electrostatic force and gravity, and reach the spinning receiving plate 14 for collection.

[0034] Example 2

[0035] The structure of this embodiment is the same as that of embodiment 1. The difference is that Figure 2 As shown, the inner tube of the slit metal solution channel 2 is a truncated cone structure that gradually narrows from bottom to top, and the bubble tube 3 is fitted and fixed to the slit metal solution channel 2, so that the bubble tube 3 is also a truncated cone pipe that gradually narrows from bottom to top.

[0036] Example 3

[0037] The structure of this embodiment is the same as that of embodiment 1. The difference is that Figure 3 As shown, the bottom end of the slit-type metal solution channel 2 is connected to the truncated cone container 10, and the truncated cone container 10 is connected to the injection pump 11. The injection pump 11 squeezes the solution in the truncated cone container 10, and then the solution is ejected through the nozzle of the slit-type metal solution channel 2.

[0038] Example 4

[0039] The structure of this embodiment is the same as that of embodiment 1. Figure 5 As shown, eight air inlets are provided at the bottom end of the hot air flow channel 1 , and eight hot air flow conduits 6 are respectively connected to the eight air inlets of the hot air flow channel 1 .

[0040] The use principle of the hot air flow assisted slit bubble electrospinning device provided by the present invention is:

[0041] The propeller 9 or the injection pump 11 pumps the solution through the bottom of the slit metal solution channel 2 to the outlet of the bubble tube 3. During the flow of the solution, the speed in the middle of the slit is the largest, and the speed on the inner and outer walls of the slit metal solution channel 2 is zero. The polymer solution macromolecules are arranged more and more orderly as they flow in the slit, and finally, bubbles are generated at the top nozzle of the slit metal solution channel 2 under the action of the airflow at the outlet. The positive end of the electrostatic generator 4 is connected to the slit metal solution channel 2 and high-voltage static electricity is applied. At the same time, the hot air flow compressor 7 releases hot air flow to the hot air flow channel 1 through the hot air flow duct 6. The hot air flow is accelerated in the gradually narrowing channel due to the narrow tube effect, and finally the bubbles are lifted at an elevation angle and help the polymer molecular chains to be evenly arranged parallel to the bubble surface. After the bubbles break, a large number of thin fragments are formed, which are stretched under the action of electrostatic force and gravity to prepare nanofibers, and reach the spinning collection plate 14 along the hot air flow channel.

[0042] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A hot air flow assisted slit bubble electrospinning device, characterized in that: It comprises a hot air flow channel (1), a slit-type metal solution channel (2), a bubble tube (3) and an electrostatic generator (4); The hot gas flow channel (1) and the slit-type metal solution channel (2) are both truncated cone-shaped pipes formed by gradually narrowing inner and outer pipes; the inner pipe diameter of the hot gas flow channel (1) is the same as the outer pipe diameter of the slit-type metal solution channel (2); the slit-type metal solution channel (2) penetrates the inner pipe of the hot gas flow channel (1) and is fitted and fixed to the inner pipe of the hot gas flow channel (1); the bubble tube (3) extends and is fixed to the inner pipe of the slit-type metal solution channel (2); and the electrostatic generator (4) is connected to the slit-type metal solution conduit (2) via a wire (5).

2. A hot air flow assisted slot-bubble electrospinning device according to claim 1, characterized in that: The hot air flow channel (1) is connected to the hot air flow compressor (7) via a hot air flow conduit (6), the maximum distance between the inner tube and the outer tube of the hot air flow channel (1) is ≤10 cm, and the elevation angle between the hot air flow channel (1) and the horizontal plane is 0 to 90 degrees.

3. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The top of the hot air flow channel (1) is lower than the top of the slit-type metal solution channel (2), and the distance between the top of the hot air flow channel (1) and the top of the slit-type metal solution channel (2) is ≤10 cm.

4. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The portion of the slit-type metal solution channel (2) that is not attached to the hot air flow channel (1) is a columnar hollow channel structure, the columnar hollow channel of the slit-type metal solution channel (2) is connected to a push rod (8), and a thruster (9) of the push rod (8) abuts against the columnar hollow channel of the slit-type metal solution channel (2).

5. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The bottom end of the slit-type metal solution channel (2) is connected to a truncated cone-shaped container (10), and the truncated cone-shaped container (10) is connected to a syringe pump (11).

6. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The maximum channel width of the slit-type metal solution channel (2) is ≤5 cm.

7. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The material of the slit-type metal solution channel (2) is a conductive material; The material of the hot air flow channel (1) is insulating material.

8. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The bubble tube (3) is connected to an air compressor (13) via an air conduit (12); the top of the bubble tube (3) is lower than the top of the slit-type metal solution channel (2); and the distance difference between the top of the bubble tube (3) and the top of the slit-type metal solution channel (2) is ≤10 cm.

9. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The positive electrode of the electrostatic generator (4) is connected to the slit-type metal solution channel (2) via a wire (5), and the negative electrode of the electrostatic generator (4) is connected to a spinning receiving plate (14) via a wire (5), and the spinning receiving plate (14) is located in the direction of the nanofibers ejected by the jet formed by static electricity from the slit-type metal solution channel (2).

10. The hot air flow assisted slot bubble electrospinning device according to claim 1, characterized in that: The bottom end of the hot air flow channel (1) is provided with 4 to 8 air inlets.

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