A preparation device for thermal polymer microtubes

Abstract

The present invention discloses a preparation device for thermal polymer microtubes, which is fixed on a frame and is characterized in that it includes a wire storage device, a lower electrode, a polymer storage tank, a heater, an upper electrode and a pushing device; wherein the metal wire is output from the wire storage device and passes through the lower electrode, the polymer storage tank, the heater and the upper electrode from bottom to top in sequence, and the upper electrode can move up and down under the push of the pushing device. Compared with the prior art, the present invention improves the production efficiency of polymer microtubes and stably controls their outer diameters through a detachable polymer storage tank with multiple curing channels that can control the temperature of the internal polymer, a sealing system that allows the metal wire to pass continuously, a wire storage device that can provide constant tension, and an upper electrode device that is easy to clamp fine metal wires and move independently.

Description

Technical field:

[0001] The invention relates to the technical field of high molecular polymer molding, in particular to a preparation device for a micron-level inner diameter flexible thermal polymer microtube capable of accurately controlling the outer diameter. Background technology:

[0002] Existing flexible polymer microtubes are usually produced by extrusion molding. Since thermosetting high-elastic polymers have a slow curing speed, for polymer microtubes with micrometer-level inner diameters, this method must use thermoplastics for extrusion, which limits its application in biocompatible thermosetting high-elastic polymer materials such as PDMS (polydimethylsiloxane).

[0003] Patent CN109071942 A proposes a method for making polymer microtubes with a micron inner diameter. However, this method only controls the outer diameter of the polymer microtube, and does not control the temperature of the polymer storage tank, resulting in failure to control the outer diameter of the polymer microtube, which leads to differences in outer diameters during production of different batches; the pulling speed of the metal wire is slow, and the production speed using a single channel is extremely slow. A typical 30cm long microtube takes 150 minutes to pull out from the unpolymerized polymer; the polymer after heating is a viscous liquid, which is difficult to remove, resulting in a long time for the device to be reset to a production state; if a disposable polymer storage tank is used, each time a new polymer storage tank is replaced, the micron-level metal wire is very fragile, and it takes a long time to re-erect the line and seal the polymer storage tank; at the same time, since the fragility of the metal wire will be significantly enhanced under the high temperature state of power supply, the use of an external electrode is likely to cause the metal wire to break; during the pulling process, failure to control the tension of the metal wire may lead to uneven pulling speed and metal wire breakage. Summary of the invention:

[0004] In order to overcome the technical problems existing in the prior art, the present invention proposes a device for preparing a precursor of a flexible polymer tube with a micron-level inner diameter, which can process thermosetting high-elastic polymer materials. The metal wire steering and fixing system is combined with electrodes to simplify the steps of electrifying the metal wire; multiple grooves are used for molding, which greatly improves the efficiency of flexible polymer microtube production, and controls the temperature of thermosetting polymer materials in real time to keep the outer diameter of each microtube produced equal; the residual polymer is taken out after solidification to avoid the removal of uncured thermosetting materials that are difficult to clean; at the same time, a detachable metal wire fixing method is used, so that the metal wire can be continuously operated without repeating the difficult process of passing through the sealed micropores; and a magnetic tension retainer is used to keep the tension of the metal wire stable during pulling. In addition to being further used for the production of polymer flexible microtubes, it can also be used for the production of micron-level inner diameter flexible tubes of biocompatible thermosetting hydrogels and other materials. The purpose of the present invention is to provide

[0005] To achieve the above-mentioned purpose, the technical solution provided by the present invention is as follows: a preparation device for thermal polymer microtubes, the preparation device is fixed on a frame, and includes a wire storage device, a lower electrode, a polymer storage tank, a heater, an upper electrode and a pushing device; wherein, after the metal wire is output from the wire storage device, it passes through the lower electrode, the polymer storage tank, the heater and the upper electrode from bottom to top in sequence, and the upper electrode can move up and down under the push of the pushing device.

[0006] In one embodiment, the wire storage device comprises a spool on which the metal wire can be wound and a magnetic tension retainer which can maintain the tension of the metal wire, and the wire storage device is arranged on both sides of the lower end of the frame.

[0007] In one embodiment, the lower electrode is arranged between the two wire storage devices, and an electrode wheel and a guide wheel are arranged on the lower electrode, and the electrode wheel and the guide wheel are arranged at intervals along the length direction of the lower electrode.

[0008] In one embodiment, the polymer storage tank is arranged above the lower electrode; wherein, the polymer storage tank includes a front plate, a rear plate and a lower sealing plate, and a semicircular groove is provided at the relative position of the front and rear plates, and a circular groove is formed after the front and rear plates are combined; the front plate is installed on a first slider perpendicular to the frame, the first slider can move along a first guide rail, the rear plate is fixed on the frame, the lower sealing plate is installed at the bottom of the front and rear plates, and can slide along a second guide rail installed on the frame, and a through hole matching the circular groove is provided on the lower sealing plate.

[0009] In one embodiment, a temperature sensor for measuring the temperature of the front and rear plates is provided in the polymer storage tank.

[0010] In one embodiment, an outer side of the front plate is further provided with an outer sub-plate, on which a water channel and inlet and outlet water holes are provided. Water is supplied by an external cooling device and enters and exits the water channel of the outer sub-plate through the inlet and outlet water holes.

[0011] In one embodiment, the heater comprises two metal heating plates mounted together, an electric heating film is mounted on the metal heating plates, and a heat insulation sheet for slowing down air convection is also provided on the heater, the heat insulation sheet is mounted on the upper and lower end surfaces of the metal heating plates.

[0012] In one embodiment, a plurality of clamping blocks capable of fixing metal wires are provided on the upper electrode, and each clamping block can be connected to each other; the electrode wheel and the clamping blocks can be adjusted to be connected in series or in parallel through different connection relationships of the metal wires.

[0013] In one embodiment, the pushing device includes a lead screw and a lead screw slider, and the upper electrode is arranged on the lead screw slider. The upper electrode is driven by the pushing device to move along the length direction of the lead screw, thereby driving the metal wire to be pulled.

[0014] In one embodiment, a guide nozzle is provided in the through hole of the lower sealing plate, and the aperture of the guide nozzle matches the diameter of the metal wire.

[0015] The present invention solves the current problems of low production efficiency and difficulty in controlling the outer diameter of polymer microtubes. Compared with the prior art, the present invention improves the production efficiency of polymer microtubes and stably controls their outer diameters through a detachable polymer storage tank with multiple curing channels that can control the temperature of the internal polymer, a sealing system that allows metal wires to pass continuously, a wire storage device that can provide constant tension, and an upper electrode device that is convenient for clamping fine metal wires and independently moving. Description of the drawings:

[0016] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always represent the same features, wherein:

[0017] Figure 1 A schematic diagram of the three-dimensional structure of a device for preparing thermal polymer microtubes in one embodiment of the present invention is disclosed.

[0018] Figure 2 A front view structural schematic diagram of a thermal polymer microtube preparation device in one embodiment of the present invention is disclosed.

[0019] Figure 3 A left-side structural schematic diagram of a thermal polymer microtube preparation device in one embodiment of the present invention is disclosed.

[0020] Figure 4 A rear structural schematic diagram of a thermal polymer microtube preparation device in one embodiment of the present invention is disclosed.

[0021] Figure 5 A schematic top view of a thermal polymer microtube preparation device according to an embodiment of the present invention is disclosed.

[0022] Figure 6 A cross-sectional view of a device for preparing a thermal polymer microtube according to an embodiment of the present invention is disclosed.

[0023] In the figure: 1 wire storage device, 11 wire shaft, 12 magnetic tension holder, 2 lower electrode, 21 electrode wheel, 22 guide wheel, 3 polymer storage tank, 31 rear plate, 32 front plate, 33 rear plate sub-plate, 34 front plate sub-plate, 35 guide rail, 36 lower sealing plate, 37 guide rail, 38 water inlet and outlet, 39 polymer channel, 4 heater, 41 metal heating plate, 42 heat insulation sheet, 43 guide rail, 5 upper electrode, 51 metal wire block, 52 guide rail, 53 screw guide rail, 6 pushing device, 61 upper electrode block, 62 guide rail, 63 screw, 64 screw slider, 65 slider, 66 guide rail, 7 frame. Specific implementation method:

[0024] refer to Figure 1 Combined with Figures 2 to 6 In an embodiment of the present invention, a thermal polymer microtube preparation device includes: a wire storage device 1, a lower electrode 2, a polymer storage tank 3, a heater 4, an upper electrode 5 and a pusher 6. The wire storage device 1, the lower electrode 2, the PDMS storage tank 3, the heater 4, the upper electrode 5 and the pusher 6 are fixedly arranged by a frame 7.

[0025] The wire storage device 1 is located at the bottom of the device, and can be located directly below the device or on both sides. The wire storage device 1 includes a wire reel 11 wound with metal wire and a magnetic tension controller 12. The reel is connected to the magnetic tension controller to keep the metal wire tension stable during the pulling process.

[0026] Preferably, the wire storage device 1 may be provided with a cover to protect the metal wire and isolate external dust. The lower electrode 2 may be level with the wire storage device 1, located at the lowest end of the device, and is equipped with a guide wheel 22 and an electrode wheel 21, which are used for turning the metal wire and can also serve as a part of the electrode when power is turned on. The electrode wheel 21 and the electrode wheel shaft are both made of copper, and the wheel shafts can be connected to each other and connected to an electrode of an external power source.

[0027] Preferably, the polymer storage tank 3 is located above the wire storage device 1, and includes three parts: a front plate, a rear plate and a lower sealing plate. The front plate and the rear plate of the polymer storage tank have several semicircular grooves, which can be assembled into several complete circular polymer grooves. The number of grooves can be increased or decreased according to demand. Both the front plate and the rear plate have outer sub-plates, and the outer sub-plates are provided with water channels and water inlets and outlets, which are connected to the external cooling water device. At the same time, there is a temperature sensor in the polymer storage tank for measuring the temperature of the front and rear plates. The front plate 32 and the rear plate 31 can be temperature controlled by the cooling water device. The front plate 32 is a movable plate, which is installed on the guide rail and can be moved back and forth through the track to facilitate the removal of the cured polymer. The rear plate 31 is fixed on the frame.

[0028] Preferably, the lower sealing plate 36 is mounted on a slide rail and can be moved up and down to facilitate the removal of the solidified polymer. The lower sealing plate has a hole at a position corresponding to the polymer channel, and a guide nozzle with an inner hole diameter close to that of the metal wire is provided in the hole to prevent polymer leakage while ensuring that the metal wire can pass through. The guide nozzle can be selected with different inner hole diameters according to the diameter of different metal wires.

[0029] Preferably, the heater 4 is located above the polymer storage tank 3. The heater 4 is composed of two metal heating plates, on which an electric heating film is installed, which can heat the polymer precursor that has been pulled out to further solidify it. At the same time, there is a heat insulation sheet 42 on the heater 4 to slow down air convection to prevent the influence of external air flow on the uncured PDMS. At the same time, the heater is installed on the guide rail and can be quickly disassembled or moved to facilitate the removal of the cured PDMS.

[0030] Preferably, the upper electrode 5 is used to clamp the metal wire and serve as one end of the electrode. A clamping block 51 is provided on the upper electrode 5 to fix the metal wire and serve as another part of the electrode. The clamping block 51 can be made of copper and can be connected to each other and to another electrode of the external power supply.

[0031] Preferably, the connection between the electrode wheels 21 of the upper electrode and the lower electrode and the clamping blocks can be adjusted so that the metal wires are connected in series or in parallel.

[0032] Preferably, the upper electrode 5 can be mounted on the upper electrode block 61, can be connected to the pushing part of the screw rod, and can be removed and replaced separately.

[0033] Preferably, the pushing device 6 is divided into an upper electrode block 61 and a pushing part, which can be connected to the upper electrode 5 and push the upper electrode 5 to move, thereby driving the metal wire to be pulled up and down. The pushing part can be a screw guide rail 53 or a pulley guide rail system. The screw guide rail 53 is used in this example.

[0034] Example 1

[0035] The operation method of the device for preparing a micron-sized inner diameter flexible polymer tube in this embodiment is as follows:

[0036] Step 1) Wind the metal wire on the bobbin 11 and install it on the magnetic tension retainer 12. The upper electrode 5 is located at the lower position of the guide rail and is connected to the pushing device 6.

[0037] Step 2) The metal wire is passed through the lower electrode 2, the lower sealing plate 36, the heater 4 to the upper electrode 5 in sequence, and is fixed on the metal wire pressing block 51.

[0038] Step 3) Fix the components of the polymer storage tank 3 and the heating plate properly: the front plate 32 and the rear plate 31 are pressed tightly together, the lower sealing plate 36 and the front and rear plates 31 and 32 are pressed tightly together, and the two pieces of the heating plate are pressed tightly together.

[0039] Step 4) Prepare the polymer, remove air bubbles by vacuuming, and add it into the polymer storage tank 3.

[0040] Step 5) Add cooling water of a specific temperature into the clamping plate of the polymer storage tank 3 until the polymer temperature stabilizes at a predetermined value.

[0041] Step 6) Applying current to the metal wire for a certain period of time through the electrodes.

[0042] Step 7) Add 0°C cooling water into the clamping plate of the polymer storage tank 3 to cool the polymer to 0°C.

[0043] Step 8) Turn on the heater to heat to a predetermined temperature.

[0044] Step 9) Open the pushing device 6 and pull the metal wire until the polymer microtubes formed on the metal wire are completely separated from the polymer storage tank 3.

[0045] Step 10) Add 100°C water to the clamping plate of the polymer storage tank for 40 minutes until the polymer inside is completely solidified. Then cool it by passing room temperature cooling water.

[0046] Step 11) Cut the wire above the polymer storage tank, remove the upper electrode 5 together with the microtube precursor, insert a new upper electrode 5 below the guide rail 43, and lower the pusher 6 to connect with the newly inserted upper electrode 5.

[0047] Step 12) Pull open the front plate of the polymer storage tank 3 , the lower sealing plate 36 and the heating plate 41 , move the metal wire to separate the solidified polymer from the polymer storage tank 3 , and pull the processed solidified polymer upward to separate it from the polymer storage tank 3 .

[0048] Step 13) Fix the metal wire at the bottom of the solidified polymer onto the newly placed upper electrode 5, cut the metal wire above the upper electrode 5, and remove the solidified polymer.

[0049] Step 14) Check whether there is any polymer residue in the polymer pool and remove the residue.

[0050] Enter the state before step 3, the system is reset, and the process 3-14 can be repeated.

[0051] The metal wire can be 80um tungsten wire, the polymer can be PDMS (polydimethylsiloxane), the ratio can be 10:1, the PDMS temperature is 20°C, the current is 0.968A, the power-on time is 4 minutes, and the temperature of the heating plate is 90°C, then a PDMS microtube precursor with an outer diameter of 550um can be obtained.

[0052] Compared with the prior art, the device uses a polymer storage tank with multiple channels that can control the internal temperature and is easy to open, and a heating plate that can be opened and closed and has an air flow restriction function. By controlling the temperature of the polymer precursor, the outer diameter of the metal wire is stably controlled and the production efficiency is greatly improved;

[0053] The magnetic tension retainer 12 is used to maintain the tension of the metal wire, ensuring the uniformity of speed and structural stability during the pulling of the metal wire; the upper and lower electrodes are used as the fixed ends and guide ends of the metal wire, which greatly simplifies the operation of electrifying the metal wire;

[0054] The use of an openable and closable polymer storage tank and heating plate, an independently replaceable and movable upper electrode, and a sealing system that can seal the polymer while allowing the metal wire to pass freely simplifies the cleaning of polymer residues and the repeated wiring of the metal wire, making the continuous production of microtube precursors possible.

[0055] In general, the present invention stably controls the outer diameter of the microtube precursor and greatly improves the production efficiency of the microtube.

[0056] It should be noted that the prior art in the protection scope of the present invention is not limited to the embodiments given in the present application documents. All prior art that does not contradict the scheme of the present invention, including but not limited to prior patent documents, prior public publications, prior public use, etc., can be included in the protection scope of the present invention. In addition, the combination of various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them. It should also be noted that the embodiments listed above are only specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or deformations made therewith can be directly derived or easily associated by those skilled in the art from the content disclosed in the present invention, and should all belong to the protection scope of the present invention.

Claims

1. A preparation device for thermal polymer microtubes, the preparation device being fixed on a frame, characterized in that: It includes a wire storage device, a lower electrode, a polymer storage tank, a heater, an upper electrode and a pushing device; wherein the metal wire is output from the wire storage device and passes through the lower electrode, the polymer storage tank, the heater and the upper electrode from bottom to top in sequence, and the upper electrode can move up and down under the push of the pushing device; The polymer storage tank is arranged above the lower electrode; wherein the polymer storage tank comprises a front plate, a rear plate and a lower sealing plate, a semicircular groove is arranged at the relative position of the front and rear plates, and a circular groove is formed after the front and rear plates are combined; the front plate is mounted on a first slider perpendicular to the frame, the first slider can move along a first guide rail, the rear plate is fixed on the frame, the lower sealing plate is mounted on the bottom of the front and rear plates, and can slide along a second guide rail mounted on the frame, and a through hole matching the circular groove is arranged on the lower sealing plate; An outer sub-plate is also provided on the outer side of the front plate. A water channel and inlet and outlet water holes are provided on the outer sub-plate. Water is supplied by an external cooling device and enters and exits the water channel of the outer sub-plate through the inlet and outlet water holes.

2. The preparation device according to claim 1, characterized in that: The wire storage device comprises a wire spool on which the metal wire can be wound and a magnetic tension retainer which can maintain the tension of the metal wire. The wire storage device is arranged on both sides of the lower end of the frame.

3. The preparation device according to claim 1, characterized in that: The lower electrode is arranged between the two wire storage devices, and an electrode wheel and a guide wheel are arranged on the lower electrode, and the electrode wheel and the guide wheel are arranged at intervals along the length direction of the lower electrode.

4. The preparation device according to claim 1, characterized in that: A temperature sensor for measuring the temperature of the front and rear plates is provided in the polymer storage tank.

5. The preparation device according to claim 1, characterized in that: The heater comprises two metal heating plates installed together, an electric heating film is installed on the metal heating plates, and a heat insulation sheet for slowing down air convection is also provided on the heater, and the heat insulation sheet is installed on the upper and lower end surfaces of the metal heating plates.

6. The preparation device according to claim 5, characterized in that: A plurality of clamping blocks for fixing metal wires are arranged on the upper electrode, and each clamping block can be connected to each other; the electrode wheel of the lower electrode and the clamping blocks can be adjusted to be connected in series or in parallel through different connection relationships of the metal wires.

7. The preparation device according to claim 6, characterized in that: The pushing device comprises a lead screw and a lead screw slider, the upper electrode is arranged on the lead screw slider, and the upper electrode is moved along the length direction of the lead screw by the driving of the pushing device, thereby driving the metal wire to be pulled.

8. The preparation device according to claim 1, characterized in that: A guide nozzle is arranged in the through hole of the lower sealing plate, and the aperture of the guide nozzle matches the diameter of the metal wire.

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