Device for preparing liquid metal microwires

Abstract

The utility model relates to a device for preparing liquid metal microwires, which comprises a water tank, fixed tweezers and movable tweezers are arranged in the water tank, the movable tweezers are driven by an electric mechanism to translate back and forth along the stretching direction of the liquid metal microwires, and a temperature control component is arranged on the water tank. The device is simple in structure and good in manufacturability, and liquid metal microwires with the diameter smaller than 100 micrometers and good stability and high repetition rate can be effectively prepared.

Description

Technical Field

[0001] The utility model relates to a device for preparing liquid metal microwires, belonging to the field of micro-nano manufacturing. Background Art

[0002] Liquid metal has great application potential in the field of neural electrodes and flexible electronics due to its excellent conductivity, fluidity and good biocompatibility. Common neural electrodes are in planar form and microwire form. The microwire form has a small diameter, which is beneficial to reduce tissue damage during implantation. Electrodes made of liquid metal have the advantages of flexibility and stretchability, which is beneficial to reduce mechanical damage to neural tissue during long-term implantation and improve the reliability of electrodes during use.

[0003] At present, the main methods for preparing liquid metal microwire electrodes include microfluidic control method, spinning method, 3D printing method, etc. The alignment error between the upper mold and the lower mold in the microfluidic control method is difficult to control, and the microtunnel is easily blocked by residual powder or bubbles in the liquid metal. In the spinning method, the polymer shell is often formed slowly and the mechanical strength of the shell is insufficient. In addition, the diameter of the microwire is affected by multiple factors such as the spinning speed, polymer concentration, and electrolyte pH value, and cannot be adjusted simply by adjusting the nozzle diameter. The quality of the pattern produced by the 3D printing method is extremely dependent on the printing parameters, and the maintenance cost of the printing equipment is very high. In summary, although the above methods can all produce microwires, there are deficiencies such as instability and high equipment requirements during the preparation process.

[0004] Fine liquid metal microwires with a diameter of less than 100 μm can be prepared by dip-coating an insulating layer and stretching it, which has the advantage of a simple process, and liquid metal microwires of different diameters can be obtained by controlling the stretching multiple. At the same time, the dip-coated polyurethane shell can be stretched at room temperature before it is fully cured, and this process does not require high-temperature heating of the polyurethane shell. Despite this, there is currently a lack of equipment that can be used to batch and stably prepare liquid metal microwires.

[0005] Aiming at this problem, the utility model proposes a device for preparing liquid metal microwires by using dipping and stretching methods. Utility Model Content

[0006] In view of the deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a device for preparing liquid metal microwires.

[0007] In order to solve the above technical problems, the technical solution of the utility model is: a device for preparing liquid metal microwires, comprising a water tank, wherein fixed tweezers and movable tweezers are arranged inside the water tank, and the movable tweezers are driven by an electric mechanism to reciprocate along the stretching direction of the liquid metal microwires, and a temperature control component is arranged on the water tank.

[0008] Preferably, the water tank is an elongated tank body, and the notch is located at the top of the tank body.

[0009] Preferably, the temperature control component comprises a water inlet and a drain outlet, the water inlet is provided with a water inlet ball valve, and the drain outlet is provided with a drain ball valve.

[0010] Preferably, the temperature control component includes a cooling plate and a heating plate, and the cooling plate and the heating plate are arranged on the inner bottom of the water tank.

[0011] Preferably, the electric mechanism adopts a ball screw pair driven by a stepper motor.

[0012] Preferably, the ball screw pair includes a base, a ball screw is installed on the base via a bearing and a bearing seat, one end of the ball screw is connected to the output shaft of the stepper motor via a coupling, a ball nut is threaded on the ball screw, a movable tweezers mounting seat is fixedly connected to the ball nut, and a slider and slide rail moving pair is connected between the movable tweezers mounting seat and the base.

[0013] Preferably, the slider and slide rail moving pair comprises a slide rail fixedly connected to the base, the slide rail is provided with a slider, and the slider is fixedly connected to the movable tweezers mounting seat.

[0014] Preferably, the movable tweezers are fixedly connected to a movable tweezers mounting seat, the fixed tweezers are fixedly connected to a fixed tweezers mounting seat, and the fixed tweezers mounting seat is fixedly connected to a bearing seat.

[0015] Preferably, the clamping openings of the fixed tweezers and the movable tweezers both extend from top to bottom into the water tank.

[0016] Compared with the prior art, the utility model has the following beneficial effects: the device for preparing liquid metal microwires can efficiently prepare liquid metal microwires with good stability and high repetition rate and a diameter of less than 100 μm. It has a simple structure and good processability. The experimental conditions only require warm water to melt the liquid metal, and no high-temperature heating is required.

[0017] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of Example 1 of the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of Example 2 of the present invention.

[0020] Figure 3 Schematic diagram of the structure of fixed / movable tweezers.

[0021] Figure 4 Schematic diagram of the process flow of the “dip-coating-stretching” method. DETAILED DESCRIPTION

[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0023] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0024] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0025] like Figure 1 , 4 As shown, this embodiment 1 provides a device for preparing liquid metal microwires, including a water tank 1, wherein fixed tweezers 2 and movable tweezers 3 are arranged inside the water tank, and the movable tweezers are driven by an electric mechanism 4 to reciprocate along the stretching direction of the liquid metal microwires, and a temperature control component is arranged on the water tank.

[0026] In Example 1 of the utility model, the water tank is a long strip-shaped tank body, and its notch is located at the top of the tank body.

[0027] In the first embodiment of the present invention, the electric mechanism adopts a ball screw pair driven by a stepper motor 5. The controller 21 is electrically connected to the stepper motor and is used to control the start and stop and speed change of the stepper motor.

[0028] In Embodiment 1 of the present invention, the fixed tweezers and the movable tweezers need to be kept at the same level.

[0029] In Example 1 of the utility model, the ball screw pair includes a base 6, on which a ball screw 8 is installed via a bearing and a bearing seat 7, one end of the ball screw is connected to the output shaft of the stepper motor via a coupling 9, a ball nut 10 is threaded on the ball screw, a movable tweezers mounting seat 11 is fixedly connected to the ball nut, and a slider and rail moving pair is connected between the movable tweezers mounting seat and the base.

[0030] In Example 1 of the utility model, two infrared limiters 20 are installed at both ends of one side of the base to limit the movement of the movable tweezers mounting seat and prevent the movable tweezers mounting seat from moving too far and colliding.

[0031] In the first embodiment of the utility model, the slider and rail moving pair comprises a rail 12 fixedly connected to the base, a slider 13 is arranged on the rail, and the slider is fixedly connected to the movable forceps mounting seat.

[0032] In Example 1 of the utility model, the movable tweezers are fixedly connected to the movable tweezers mounting seat, the fixed tweezers are fixedly connected to the fixed tweezers mounting seat 14, and the fixed tweezers mounting seat is fixedly connected to the bearing seat.

[0033] In Example 1 of the utility model, the temperature control component includes a water inlet and a water outlet. The water inlet is provided with a water inlet ball valve 15, and the water outlet is provided with a water outlet ball valve 16.

[0034] In Example 1 of the utility model, the clamping openings of the fixed tweezers and the movable tweezers both extend from top to bottom into the water tank.

[0035] like Figure 2 , 4 As shown, in the embodiment 2 of the present utility model, different from the embodiment 1, the temperature control assembly includes a cooling plate 17 and a heating plate 18, and the cooling plate and the heating plate are arranged at the inner bottom of the water tank. A temperature sensor 19 is installed on the side of the water tank.

[0036] A method for preparing a device for preparing liquid metal microwires is carried out according to the following steps:

[0037] S1, pure gallium with a melting point of 29.8°C is injected into a silicone tube with an inner diameter of D1 and a length of L1 and frozen and solidified, and the silicone tube is cut open with a surgical blade to obtain a liquid metal bare wire with a diameter of D1 and a length of L1;

[0038] S2, for a liquid metal bare wire with a diameter of D1, a polyurethane shell is dip-coated in a PU-DMF solution with a concentration of C at a speed of V1;

[0039] S3, clamping the two ends of the liquid metal wire with a diameter of D1 after dipping onto the fixed tweezers and the movable tweezers respectively;

[0040] S4, pour T1 warm water into the water tank until it covers the liquid metal wire with a diameter of D1;

[0041] S5, after the liquid metal wire with diameter D1 melts, the electric mechanism is started, and the movable tweezers mounting seat starts to move at a speed of V2. According to the formula The volume of the microfilaments remains unchanged before and after stretching. By stretching to N times the original length, a liquid metal microfilament with a diameter of D2 can be obtained;

[0042] S6, adjusting the water temperature by a temperature control component to solidify the drawn liquid metal microfilaments;

[0043] S7. After the thinned liquid metal microwire solidifies, remove the microwire and use tetrahydrofuran to dissolve the polyurethane shell on the surface to obtain the thinned liquid metal bare wire with a diameter of D2.

[0044] The inner diameter D1 of the silicone tube in S1 can be 200-500 μm, and the length L1 can be 1-6 cm. The concentration C of the polyurethane (PU)-N, N-dimethylformamide (DMF) solution can be 10%-30%, and the dipping speed V1 can be 10-100 mm / min. The temperature T1 of the warm water in S4 can be 33-40°C. The moving speed V2 of the movable tweezers mounting seat in S5 can be 5-20 mm / min, the diameter D2 of the microfilament is the required diameter, and the stretching multiple is The cool water temperature T2 in S6 can be 0-20°C.

[0045] Specific implementation process:

[0046] Embodiment 1:

[0047] S1. Pure gallium with a melting point of 29.8°C was injected into a silicone tube with an inner diameter of 300 μm and frozen solidified. The silicone tube was cut open with a surgical blade to obtain a liquid metal bare wire with a diameter of 300 μm.

[0048] S2, a liquid metal bare wire with a diameter of 300 μm is dip-coated with a polyurethane shell in a 20% PU-DMF solution at a speed of 50 mm / min;

[0049] S3, clamping the two ends of the dip-coated liquid metal wire with a diameter of 300 μm onto a fixed tweezer and a movable tweezer respectively;

[0050] S4, inject 33-40℃ warm water into the water tank until the liquid metal wire with a diameter of 300μm is submerged;

[0051] S5. After the liquid metal wire with a diameter of 300 μm is melted, the electric mechanism is started, and the movable tweezers mounting seat starts to move at a speed of 10 mm / min. According to the formula The volume of the microfilaments remains unchanged before and after stretching. By stretching it to nine times its original length, a liquid metal microfilament with a diameter of 100 μm can be obtained;

[0052] S6, opening the water injection ball valve and the drainage ball valve, draining the warm water and injecting cold water, and solidifying the drawn liquid metal microwires by adjusting the water temperature;

[0053] S7. After the drawn liquid metal microwires are solidified, the microwires are removed and the polyurethane shell on the surface is dissolved with tetrahydrofuran to obtain the drawn liquid metal bare wires with a diameter of 100 μm.

[0054] Embodiment 2:

[0055] S1. Pure gallium with a melting point of 29.8°C was injected into a silicone tube with an inner diameter of 300 μm and frozen solidified. The silicone tube was cut open with a surgical blade to obtain a liquid metal bare wire with a diameter of 300 μm.

[0056] S2, a liquid metal bare wire with a diameter of 300 μm is dip-coated with a polyurethane shell in a 20% PU-DMF solution at a speed of 50 mm / min;

[0057] S3, clamping the two ends of the dip-coated liquid metal wire with a diameter of 300 μm onto a fixed tweezer and a movable tweezer respectively;

[0058] S4, turn on the heating plate to raise the water temperature to 33-40°C, at which point the liquid metal wire with a diameter of 300 μm begins to melt;

[0059] S5. After the liquid metal wire with a diameter of 300 μm melts, turn off the heating plate, start the electric mechanism, and the movable tweezers mounting seat starts to move at a speed of 10 mm / min. According to the formula The volume of the microfilaments remains unchanged before and after stretching. By stretching it to nine times its original length, a liquid metal microfilament with a diameter of 100 μm can be obtained;

[0060] S6, turning on the refrigeration plate to lower the water temperature to below 20° C. until the drawn liquid metal microfilaments solidify;

[0061] S7. After the drawn liquid metal microwires are solidified, the microwires are removed and the polyurethane shell on the surface is dissolved with tetrahydrofuran to obtain the drawn liquid metal bare wires with a diameter of 100 μm.

[0062] The utility model has a simple structure and good processability. The experimental conditions only require warm water to melt the liquid metal, and high temperature heating is not required. Microwires of different diameters can be obtained by changing the stretching length, which has the potential to be developed into industrial continuous production.

[0063] The above is only the preferred embodiment of the utility model, and does not limit the utility model in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the utility model without departing from the technical solution of the utility model still belongs to the protection scope of the technical solution of the utility model.

Claims

1. A device for preparing liquid metal microwires, characterized in that: The invention comprises a water tank, wherein fixed tweezers and movable tweezers are arranged inside the water tank, and the movable tweezers are driven by an electric mechanism to reciprocate along the stretching direction of the liquid metal microwire, and a temperature control component is arranged on the water tank.

2. The device for preparing liquid metal microwires according to claim 1, characterized in that: The water tank is a long strip tank body, and the notch is located at the top of the tank body.

3. The device for preparing liquid metal microwires according to claim 1, characterized in that: The temperature control component comprises a water inlet and a water outlet. The water inlet is provided with a water inlet ball valve, and the water outlet is provided with a water outlet ball valve.

4. The device for preparing liquid metal microwires according to claim 1, characterized in that: The temperature control component comprises a cooling plate and a heating plate, and the cooling plate and the heating plate are arranged on the inner bottom of the water tank.

5. The device for preparing liquid metal microwires according to claim 1, characterized in that: The electric mechanism adopts a ball screw pair driven by a stepping motor.

6. The device for preparing liquid metal microwires according to claim 5, characterized in that: The ball screw pair includes a base, a ball screw is installed on the base via a bearing and a bearing seat, one end of the ball screw is connected to the output shaft of the stepper motor via a coupling, a ball nut is threaded on the ball screw, a movable tweezers mounting seat is fixedly connected to the ball nut, and a slider and rail moving pair is connected between the movable tweezers mounting seat and the base.

7. The device for preparing liquid metal microwires according to claim 6, characterized in that: The slider and slide rail moving pair comprises a slide rail fixedly connected to a base, a slider is arranged on the slide rail, and the slider is fixedly connected to a movable tweezers mounting seat.

8. The device for preparing liquid metal microwires according to claim 6, characterized in that: The movable tweezers are fixedly connected to the movable tweezers mounting seat, the fixed tweezers are fixedly connected to the fixed tweezers mounting seat, and the fixed tweezers mounting seat is fixedly connected to the bearing seat.

9. The device for preparing liquid metal microwires according to claim 1, characterized in that: The clamping openings of the fixed tweezers and the movable tweezers both extend from top to bottom into the water tank.

Images