CN217536315U

CN217536315U - Melt-blown spinning device without spinneret orifice

Info

Publication number: CN217536315U
Application number: CN202221731687.2U
Authority: CN
Inventors: 伍晖; 李子威
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2022-07-05
Filing date: 2022-07-05
Publication date: 2022-10-04
Anticipated expiration: 2032-07-05

Abstract

A spinneret orifice-free melt-blown spinning device is provided. The spinneret orifice-free melt-blown spinning device comprises a melt tank, a heat source, a carrier and a nozzle. The melt tank defines a receiving space for receiving the melt. The heat source is used to heat the raw material of the melt. At least a portion of the carrier is capable of moving into and out of the receiving space to carry the melt away. The nozzle is used for jetting airflow to the carrier carrying the melt, and the airflow stretches the melt to enable the melt to be formed into filaments.

Description

Melt-blown spinning device without spinneret orifice

Technical Field

The application relates to the field of fiber spinning, in particular to a spinneret orifice-free melt-blown spinning device.

Background

The micro-nano fiber is a linear material with the diameter of micron or nanometer scale and larger length-diameter ratio. Due to the unique physical and chemical properties, the micro-nanofiber is widely applied to various novel functional materials.

At present, common methods for preparing micro-nanofibers include drawing methods, template synthesis methods, self-assembly methods, melt-blown spinning, wet spinning, centrifugal spinning and the like. Melt-blown spinning is the most widely used method in the current industrial production, and has the advantages of high production efficiency, no need of using solvents and the like. However, melt-blown spinning extrudes melt through the spinneret orifices to form filaments, so that the condition that the spinneret orifices of the melt-blown spinning device are blocked easily occurs, and the long-term operation of the melt-blown spinning device is limited. Therefore, the development of a melt-blown spinning device without the problem of needle blockage is of great significance.

SUMMERY OF THE UTILITY MODEL

The present application has been made in view of the state of the art described above. It is an object of the present application to provide a spinneret-orifice-free melt-blown spinning apparatus which overcomes at least one of the disadvantages described in the background above.

In order to achieve the above object, the present application adopts the following technical solutions.

The application provides a no orifice melt blown spinning device as follows, this no orifice melt blown spinning device includes: a melt tank defining a receiving space for receiving melt; a heat source for heating the feedstock of the melt; a carrier, at least a portion of which is capable of entering and exiting the containment space to carry the melt away; and a nozzle for jetting a gas flow to the carrier carrying the melt, the gas flow drawing the melt to form the melt into a filament shape.

In an alternative, the carrier is a flexible body and is supported in a U-shaped configuration, the bottom of the U-shaped configuration being located in the receiving space, the orifice-free melt-blown spinning device comprises two oppositely directed nozzles, which are located in the U-shaped configuration, the carrier being reciprocally movable in its extension direction such that the gas streams ejected from the two nozzles alternately draw the melt.

In another alternative, the support is a wire, and the support has a diameter of 0.1mm to 0.5mm.

In another alternative, the carrier is a mesh cloth, and the mesh number of the carrier is 10-2000 meshes.

In another alternative, the number of the carriers is plural, and the plural carriers are arranged side by side and spaced apart from each other.

In another alternative, the nozzle comprises a plurality of hollow tubes arranged side by side.

In another alternative, the nozzle is an air knife.

In another alternative, the distance between the output end of the nozzle and the carrier is from 2mm to 10mm.

In another optional solution, the apparatus further comprises a collecting body spaced apart from the nozzle, the nozzle is aligned with the collecting body, and the at least one portion can be located between the collecting body and the nozzle, so that the micro-nanofibers formed from the melt can adhere to the collecting body.

In another optional scheme, the device further comprises a compressed air source, wherein an output end of the compressed air source is communicated with the nozzle and is used for providing the air flow to the nozzle.

By adopting the technical scheme, the carrier is utilized to convey the melt, and the melt-blown spinning device without the spinneret orifice can carry out melt-blown spinning under the condition of not using a melt-blown die head, so that the problem that the spinneret orifice is blocked by the melt is avoided, and the stability of the melt-blown spinning device is effectively improved.

Drawings

FIG. 1 shows a perspective view of a spinneret-orifice-free melt-blown spinning apparatus according to a first embodiment of the present application.

Fig. 2 shows a schematic view of the orifice-free melt-blown spinning apparatus of fig. 1, wherein the arrows indicate the direction of movement of the moving body.

Fig. 3 shows a scanning electron microscope image of the micro-nanofibers produced by the orifice-free melt-blown spinning device in fig. 1.

Fig. 4 shows a scanning electron microscope image of the micro-nanofibers produced by the orifice-free melt-blown spinning apparatus according to the second embodiment of the present application.

FIG. 5 shows a perspective view of a spinneret-orifice-free melt blown spinning apparatus according to a third embodiment of the present application.

Fig. 6 shows a scanning electron microscope image of the micro-nanofibers produced by the orifice-free melt-blown spinning device in fig. 5.

Description of the reference numerals

1a melt supply unit; 11a melt tank; 11a receiving space; 12 a carrier; 13 a support body; 14a moving body; 14a support arm; 1a melting body;

2, an air supply unit; 21, compressing a gas source; 22 a pressure reducing valve; 23, a nozzle;

3 a collecting unit; 31 collector

Detailed Description

Exemplary embodiments of the present application are described below with reference to the accompanying drawings. It should be understood that the detailed description is only intended to teach one skilled in the art how to practice the present application, and is not intended to be exhaustive or to limit the scope of the application.

(first embodiment)

Fig. 1 and 2 show a spinneret-hole-free melt-blown spinning apparatus according to a first embodiment of the present application, which may include a melt supply unit 1, a gas supply unit 2, and a collection unit 3.

The melt supply unit 1 may include a melt tank 11, a heat source (not shown in the drawings), a carrier 12, a support 13, and a moving body 14. Specifically, the melt tank 11 may be made of stainless steel, which may define a receiving space 11a for receiving the melt 1a. The heat source may be an electric heating element, which may be mounted to the melt tank 11. For example, the heat source may be a tubular electric heater element. The carrier 12 may be a flexible body, such as stainless steel wire. A plurality of (three as illustrated) carriers 12 may be arranged side by side and spaced apart from each other in the axial direction of the support body 13. The support 13 may be a roller, and a plurality of (four as illustrated) supports 13 may be arranged parallel to each other. Two of the four support bodies 13 may be located in the accommodating space 11a, and the other two support bodies 13 of the four support bodies 13 may be located above the melt tank 11. The moving body 14 may include two arms 14a fixed to each other, and the two arms 14a may be spaced apart. One end of the carrier 12 may be fixed to one arm 14a and the other end of the carrier 12 may be fixed to the other arm 14 a. The carrier 12 may abut against four supports 13 such that the carrier 12 can be supported in a U-shaped configuration under the guidance of the supports 13. The bottom of the U-shaped structure may be located in the receiving space 11a.

Further, the carrier 12 may have a particular diameter. For example, the diameter of the support 12 may be 0.1mm to 0.5mm. Thus, the carrier 12 does not carry too much melt 1a due to its excessively large diameter to form droplets of the melt 1a, or does not carry too little melt 1a due to its excessively small diameter to affect the spinning efficiency. Preferably, the diameter of the support 12 may be 0.1mm, 0.2mm, 0.3mm, 0.4mm or 0.5mm. In this embodiment, the diameter of the carrier 12 may be 0.4mm.

The gas supply unit 2 may include a compressed gas source 21, a pressure reducing valve 22, and a nozzle 23. Specifically, the compressed air source 21 may be an air compressor, and an output end of the air compressor may be connected to the nozzle 23 through a pressure reducing valve 22. The nozzle 23 may include a hollow tube, and a plurality of hollow tubes may be arranged side by side in the axial direction of the support body 13. The internal diameter of each hollow tube may be 4mm to 10mm. In this embodiment, the inner diameter of the hollow tube may be 4mm, and the outer diameter of the hollow tube may be 6mm. The nozzle 23 may be disposed above the melt tank 11. The output end of the nozzle 23 may face the carrier 12 and be spaced apart from the carrier 12, and the air flow emitted from the nozzle 23 may pass vertically through the carrier 12. Two nozzles 23 may be provided in the U-shaped structure, and the output ends of the two nozzles 23 may be arranged opposite to each other.

Further, the nozzle 23 may be spaced a particular distance from the carrier 12. For example, the distance between the output end of the nozzle 23 and the carrier 12 may be 2mm to 10mm. In this way, the nozzle 23 is neither contaminated by the melt 1a by too small a spacing distance nor is there a large dissipation of the gas flow by too large a spacing distance. Preferably, the distance between the output of the nozzle 23 and the carrier 12 may be 2mm, 4mm, 6mm, 8mm or 10mm. In this embodiment, the distance between the output end of the nozzle 23 and the carrier 12 may be 4mm.

The collecting unit 3 may comprise a collecting body 31, and the collecting body 31 may be a hollow cage. In particular, the collection body 31 may be spaced apart from the nozzle 23, and the output end of the nozzle 23 may be directed at the collection body 31. A portion of the support 12 may be located between the collection body 31 and the nozzle 23.

The following describes a melt-blown spinning method using the orifice-free melt-blown spinning apparatus, which may generally include:

at least a part of the carrier 12 is located in the accommodation space 11a, and the melt 1a adheres to at least a part of the carrier 12;

moving at least a part of the carrier 12 from the accommodating space 11a to a flow path of the air flow; and

the melt 1a is drawn off by the gas stream.

The state shown in fig. 2 may be an initial state of the orifice-less melt-blown spinning apparatus. Specifically, the user may place the raw material of the melt 1a in the accommodation space 11a. The raw material may be polypropylene, and the mass of the raw material may be 20g. The heat source may heat the raw material and transform the raw material into melt 1a, and the heating temperature may be 220 ℃. After the raw material is converted into the melt 1a, the melt 1a may adhere to the bottom of the U-shaped structure. The moving body 14 can be moved to one side (right side in fig. 2) so that the melt 1a can be conveyed by the carrier 12 to the flow path of the gas flow of one nozzle 23 (right nozzle in fig. 2). The gas flow may draw the melt 1a adhering to the carrier 12 into a jet. Micro-nanofibers can be formed after the jet flow is solidified, and the micro-nanofibers can be attached to the collector 31 along with the air flow.

Thereafter, the moving body 14 can be moved to the other side (left side in fig. 2) so that the melt 1a can be conveyed by the carrier 12 to the flow path of the gas flow of the other nozzle 23 (left nozzle in fig. 2). The moving body 14 can reciprocate between one side and the other side so that the carrier 12 can reciprocate in the extending direction thereof, and the melt 1a can be alternately drawn by the air streams ejected from the two nozzles 23.

Compared with the traditional melt-blown spinning device, the melt 1a is conveyed by the carrier 12, and the melt-blown spinning device without the spinneret orifices can carry out melt-blown spinning without using a melt-blown die head, so that the problem that the melt 1a blocks the spinneret orifices is avoided, and the stability of the melt-blown spinning device is effectively improved.

Further, the carrier 12 may transport the melt 1a at a specific speed. For example, the moving speed of the carrier 12 may be 0.5cm/s to 20cm/s. Therefore, the melt 1a is not solidified due to the too slow moving speed of the carrier 12, and large liquid drops are not formed due to the too fast moving speed of the carrier 12, so that the quality of the micro-nano fibers is not influenced. Preferably, the carrier 12 may be fed at a speed of 0.5cm/s, 1cm/s, 2cm/s, 5cm/s, 10cm/s or 20cm/s. In the present embodiment, the feeding speed of the carrier 12 may be 5cm/s.

By adjusting the pressure reducing valve 22, the air flow can be ejected from the nozzle 23 at a specific pressure. For example, the gauge pressure of the gas stream may be from 0.01MPa to 1MPa. When the gauge pressure of the gas flow is within the above range, the drawn melt 1a is continuous and uniform. Thus, the melt 1a is not sufficiently drawn due to an excessively low gauge pressure of the gas flow, nor is it crushed due to an excessively high gauge pressure of the gas flow. Preferably, the gauge pressure of the gas stream may be 0.01MPa, 0.05MPa, 0.1MPa, 0.2MPa, 0.5MPa or 1MPa. In this embodiment, the gauge pressure of the gas stream may be 0.08MPa.

Referring to fig. 3, a Scanning Electron Microscope (SEM) image of the micro-nanofibers is shown. As can be seen from fig. 3, the micro-nanofibers are continuous and smooth.

(second embodiment)

The orifice-less melt-blown spinning apparatus according to the second embodiment of the present application is a modification of the first embodiment, and a detailed description is omitted for the same or similar features as the first embodiment.

In this embodiment, still referring to fig. 1 and 2, the melt tank 11 may be made of an aluminum alloy. The nozzle 23 may be an air knife, and the width of the nozzle 23 may be 1cm to 10cm. For example, the width of the nozzle 23 may be 3cm and the distance between the output end of the nozzle 23 and the carrier 12 may be 6mm. The compressed gas source 21 may be a high pressure gas cylinder. The moving speed of the carrier 12 may be 4cm/s. The raw material of the melt 1a may be pitch, and the mass of the raw material may be 30g. The heating temperature of the heat source may be 310 ℃.

Referring to fig. 4, a scanning electron microscope image of the micro-nanofiber produced in the present embodiment is shown. As can be seen from fig. 4, the micro-nanofibers are continuous and smooth.

(third embodiment)

The orifice-less melt-blown spinning apparatus according to the third embodiment of the present application is a modification of the first embodiment, and the same reference numerals are used in this embodiment for the same or similar features as those of the first embodiment, and detailed description of these features is omitted.

Referring to fig. 5, in the present embodiment, the carrier 12 may be a belt-shaped mesh, and the width of the carrier 12 may be 2cm. The melt 1a may cover the mesh on the carrier 12, and the gas stream ejected from the nozzle 23 may penetrate the mesh and draw the melt 1a covering the mesh. The nozzle 23 may be an air knife, and the width of the nozzle 23 may be 1cm to 10cm. For example, the width of the nozzle 23 may be 3cm and the distance between the output end of the nozzle 23 and the carrier 12 may be 2mm. The moving speed of the carrier 12 may be 3cm/s. The raw material of the melt 1a may be polycarbosilane, and the mass of the raw material may be 25g. The heating temperature of the heat source may be 230 ℃. The gauge pressure of the gas stream may be 0.1MPa.

Further, the carrier 12 may have a specific mesh size. For example, the mesh size of the carrier 12 may be 10 mesh to 2000 mesh. Thus, the spinneret-hole-free melt-blowing spinning device does not have low spinning efficiency due to the small mesh number of the carrier 12, and the jet flows formed by the melt 1a do not interfere with each other due to the large mesh number of the carrier 12. Preferably, the mesh size of the carrier 12 may be 20 mesh, 50 mesh, 80 mesh, 100 mesh, 200 mesh, 500 mesh, 800 mesh, 1000 mesh, 1500 mesh or 2000 mesh. In this embodiment, the mesh number of the carrier 12 may be 50 mesh.

Referring to fig. 6, it shows a scanning electron microscope image of the micro-nanofiber produced in this embodiment. As can be seen from fig. 6, the micro-nanofibers are continuous and smooth.

It should be understood that the above-described embodiments are exemplary only, and are not intended to limit the present application. Various modifications and alterations of the above-described embodiments may be made by those skilled in the art in light of the teachings of this application without departing from the scope thereof.

It is to be understood that the heat source may be in direct contact with the raw material or melt 1a of the melt 1a, or the raw material or melt 1a of the melt 1a may be heated by a heat medium. For example, the heat medium may be the wall of the melt tank 11 and the heat transfer oil.

It should be understood that the raw materials of melt 1a are not limited to polypropylene, pitch, and polycarbosilane, and may include any possible material known to those skilled in the art. For example, the raw material of the melt 1a may include a high molecular material and an inorganic non-metallic material. Preferably, the high molecular material may include one or more of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl alcohol, polyethylene glycol, polylactic acid-glycolic acid copolymer, polycaprolactone, polyurethane, polyvinylidene fluoride, polymethyl methacrylate, nylon, ethylene/vinyl alcohol copolymer, polyimide, polyamide, polyether sulfone, lignin, polyvinyl butyral, polycarbonate, asphalt, polycarbosilane, and polyazetasilane. The inorganic non-metallic material comprises one or more of silicon dioxide, aluminum oxide, boron oxide and aluminum silicate.

It should be understood that the carrier 12 is not limited to being a flexible body, and may be, for example, a rigid body. In the first and second embodiments, the carrier 12 is not limited to being made of stainless steel. For example, the carrier 12 may also be made of copper or nichrome. The number of the carriers 12 is not limited to three, and it may be single or plural. The carrier 12 is not limited to being continuously extended, but may be discontinuous.

It should be understood that the melt tank 11 is not limited to being made of stainless steel or aluminum alloy. For example, the melt tank 11 may be made of enamel.

It should be understood that the support body 13 is not limited to being a roller. For example, the support body 13 may be a shaft body fixed to the melt tank 11.

It should be understood that the nozzle 23 is not limited to being a hollow tube or an air knife. For example, the nozzle 23 may be a duckbill nozzle.

It should be understood that the collector 31 is not limited to being a hollow cage. For example, the collector 31 may be a web or a roll.

Claims

1. A spinneret orifice-free melt-blown spinning device, comprising:

a melt tank defining a receiving space for receiving melt;

a heat source for heating the feedstock of the melt;

a carrier, at least a portion of which is capable of entering and exiting the containment space to carry the melt away; and

and the nozzle is used for jetting airflow to the carrier carrying the melt, and the airflow stretches the melt to form the melt into filaments.

2. The orifice-free meltblown spinning apparatus of claim 1 wherein said carrier is a flexible body and is supported in a U-shaped configuration with the bottom of said U-shaped configuration being located in said receiving space, said orifice-free meltblown spinning apparatus including two said nozzles facing in opposite directions, said two nozzles being located within said U-shaped configuration, said carrier being reciprocally movable in the direction of extension thereof so that the air jets from said two nozzles alternately draw said melt.

3. The orifice-free melt blown spinning apparatus of claim 2, wherein the carrier is a wire and the diameter of the carrier is 0.1mm to 0.5mm.

4. The orifice-free meltblown spinning apparatus of claim 2 wherein the carrier is a scrim and the carrier has a mesh size of 10 to 2000 mesh.

5. The orifice-free meltblowing spinning apparatus of any one of claims 1 to 4, wherein the number of carriers is plural, and a plurality of the carriers are arranged side by side and spaced apart from each other.

6. The orifice-free meltblown spinning apparatus of any of claims 1-4 wherein the nozzle comprises a plurality of hollow tubes arranged side by side.

7. The orifice-free meltblowing spinning apparatus of any one of claims 1 to 4, wherein the nozzle is an air knife.

8. The orifice-free meltblown spinning apparatus of any of claims 1-4 wherein the distance between the output of the nozzle and the carrier is from 2mm to 10mm.

9. The orifice-free meltblown spinning apparatus of any of claims 1-4, further comprising a collector spaced from the nozzle, the nozzle being aligned with the collector, the at least a portion of the carrier being positionable between the collector and the nozzle such that the micro-nanofibers formed from the melt are attachable to the collector.

10. The orifice-free meltblown spinning apparatus of any of claims 1-4 further comprising a source of compressed gas, the output of said source of compressed gas being in communication with said nozzle for providing said gas stream to said nozzle.