A method for producing an electrically conductive polyurethane rubber and an electrically conductive polyurethane rubber

Abstract

This invention relates to the field of conductive materials technology, specifically to a method for preparing conductive polyurethane rubber and the conductive polyurethane rubber itself. The preparation method includes: S1. Adding ionic liquid 3F-Li to β-cyclodextrin, then adding alcohol, and stirring until homogeneous, so that the 3F-Li ionic liquid powder and β-cyclodextrin are miscible, obtaining a first mixture; S2. Placing the first mixture in a constant temperature drying oven and drying it at 100-130℃, so that the first mixture forms a white powder; S3. Adding the white powder to polyurethane, then adding ethyl acetate dropwise, so that the white powder dissolves in the polyurethane, obtaining a second mixture; S4. Vacuuming the second mixture and heating it at 50-80℃ until the second mixture solidifies, obtaining a PU-3F-Li conductive polyurethane composite material. This preparation method can produce conductive polyurethane rubber with good mechanical properties, good conductivity, good antistatic properties, and strong water resistance, temperature resistance, and conductivity recovery. It also has the advantages of simple operation, high efficiency, non-toxicity, and low cost.

Description

Technical Field

[0001] This invention relates to the field of conductive materials technology, specifically to a method for preparing conductive polyurethane rubber and the conductive polyurethane rubber itself. Background Technology

[0002] With the continuous development of technology, the hazards of static electricity in daily life and industry are becoming increasingly prominent. Preventing accidents such as cable discharge, hazardous chemical combustion, and instrument malfunction caused by static electricity is one of the key focuses of research on conductive materials.

[0003] Currently, conductive polyurethane materials exhibit antistatic properties. The conductivity of conductive polyurethane is influenced by the addition of conductive fillers. Commonly used conductive fillers include graphite, carbon fiber, metal powder fragments, fibers, metal-plated glass fibers, nickel-chromium coated and stainless steel mica, and metal oxides.

[0004] However, current conductive polyurethanes have poor overall performance. For example, they may have good conductivity, but poor durability, water resistance, temperature resistance, and mechanical properties, or high toxicity. Current conductive polyurethanes cannot be compatible in all aspects of performance. Summary of the Invention

[0005] One of the objectives of this invention is to overcome the shortcomings of the prior art by providing a method for preparing conductive polyurethane rubber. This method can produce conductive polyurethane rubber with good mechanical properties, good electrical conductivity, good antistatic properties, water resistance, temperature resistance, and strong electrical conductivity recovery. It also has the advantages of simple operation, high efficiency, non-toxicity, and low cost.

[0006] The second objective of this invention is to provide a conductive polyurethane rubber.

[0007] To achieve one of the above objectives, the present invention provides the following technical solution:

[0008] A method for preparing conductive polyurethane rubber is provided, comprising the following steps:

[0009] S1. Add lithium trifluoromethanesulfonate to β-cyclodextrin, then add alcohol, stir well to make lithium trifluoromethanesulfonate and β-cyclodextrin miscible, and obtain the first mixture;

[0010] S2. Place the first mixture in a constant temperature drying oven and dry it at 100~130℃ to form a white powder;

[0011] S3. Add the white powder to the polyurethane, then add ethyl acetate dropwise to dissolve the white powder in the polyurethane, thus obtaining a second mixture;

[0012] S4. Vacuum the second mixture and heat it at 50~80°C until it solidifies to obtain PU-3F-Li conductive polyurethane composite material.

[0013] In some embodiments, the polyurethane is a two-component polyurethane;

[0014] The two-component polyurethane includes polyurethane A, which is used as a polyurethane main agent; and polyurethane B, which is used as a polyurethane curing agent.

[0015] The weight ratio of polyurethane A to polyurethane B is 1:1.

[0016] In some embodiments, the weight ratio of polyurethane component A, polyurethane component B, β-cyclodextrin, and 3F-Li is 19:19:1:1.

[0017] In some embodiments, in step S3, the white powder is first added to the polyurethane A material, then the ethyl acetate is added dropwise. After the white powder dissolves in the polyurethane A material, the polyurethane B material is added and stirred until homogeneous.

[0018] In some embodiments, the alcohol is 75% alcohol.

[0019] In some embodiments, the second mixture is injected into a polyethylene mold, which is placed on a heated iron plate;

[0020] The heating plate heats the second mixture within the polyethylene mold, causing it to solidify into a PU-3F-Li conductive polyurethane composite material.

[0021] In some embodiments, the heating plate includes a first iron plate and a second iron plate, with a heating block disposed between the first iron plate and the second iron plate;

[0022] The surface of the first iron plate is covered with aluminum foil, and the bottom of the polyethylene mold is coated with petroleum jelly and placed on the first iron plate.

[0023] In some embodiments, the preparation method of the 3F-Li includes the following steps:

[0024] Lithium carbonate was added to a reaction vessel, methanol was added and stirred until homogeneous. Trifluoromethanesulfonic acid was slowly added dropwise during the stirring process. The reaction temperature was room temperature. Once the trifluoromethanesulfonic acid was completely added and the material in the reaction vessel became solid, stirring was stopped. The reactants were filtered to obtain a white solid. The white solid was then placed in a vacuum drying oven to dry, yielding 3F-Li.

[0025] In some embodiments, the molar ratio of lithium carbonate to trifluoromethanesulfonic acid is 0.5~1:2~3;

[0026] The amount of methanol added is 3-4 ml per gram of lithium carbonate.

[0027] The beneficial effects of the method for preparing conductive polyurethane rubber of the present invention are as follows:

[0028] (1) The method for preparing conductive polyurethane rubber of the present invention uses 3F-Li (lithium trifluoromethanesulfonate) as the filler material of polyurethane. Lithium ions form an association with the functional groups on the urethane segments of polyurethane. With the help of polyurethane segments, some Li ions cross the energy barrier, causing the active sites to move or be replaced. Then, lithium ions move directionally under the electric field, thus ensuring the conductivity of the conductive polyurethane rubber, i.e., the PU-3F-Li conductive polyurethane composite material.

[0029] (2) The method for preparing conductive polyurethane rubber of the present invention uses β-cyclodextrin as a carrier, adds lithium trifluoromethanesulfonate to β-cyclodextrin, and then adds 75% medical alcohol as a solvent to make lithium trifluoromethanesulfonate and β-cyclodextrin completely miscible, which overcomes the problem of 3F-Li settling to the bottom due to its high density, improves the conductivity of conductive materials and improves the utilization rate of 3F-Li; the raw materials used in this method are low in cost and environmentally friendly, and the operation method is simple and easy to operate, making it suitable for large-scale production applications.

[0030] (3) The method for preparing conductive polyurethane rubber of the present invention has the advantages of good mechanical properties, good conductivity, good antistatic properties, water resistance, temperature resistance and strong conductivity recovery of the PU-3F-Li conductive polyurethane composite material, which is suitable for various environments and effectively improves the application range of conductive polyurethane. In particular, the conductive polyurethane rubber of the present invention has good recovery performance after damage. That is, after the PU-3F-Li conductive polyurethane composite material is immersed in water and treated at high temperature, the conductive polyurethane rubber can restore its conductivity after the temperature drops, which has the advantage of good applicability.

[0031] To achieve the second objective mentioned above, the present invention provides the following technical solution:

[0032] A conductive polyurethane rubber is provided, which is prepared by the above-described method for preparing conductive polyurethane rubber. Attached Figure Description

[0033] Figure 1 This is the synthetic route for 3F-Li (lithium trifluoromethanesulfonate) of the present invention.

[0034] Figure 2 This is a diagram showing the working state of measuring the surface resistance of the PU-3F-Li conductive polyurethane composite material according to the present invention.

[0035] Figure 3 This is a diagram showing the working state of measuring the volume resistivity of PU-3F-Li conductive polyurethane composite material according to the present invention. Detailed Implementation

[0036] Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0037] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” as used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0038] Example 1

[0039] This embodiment discloses a method for preparing conductive polyurethane rubber, including the following steps:

[0040] S1. Add lithium trifluoromethanesulfonate to β-cyclodextrin, then add alcohol, stir well to make lithium trifluoromethanesulfonate and β-cyclodextrin miscible, and obtain the first mixture;

[0041] Specifically, first weigh the lithium trifluoromethanesulfonate salt and β-cyclodextrin in the formula, then add alcohol to mix them evenly, and the resulting material is the first mixture.

[0042] S2. Place the first mixture in a constant temperature drying oven and dry it at 100~130℃, preferably 120℃, so that the first mixture forms a white powder;

[0043] Specifically, the first mixture is first poured into a container, for example, a glass dish, and an asbestos mesh is placed in a constant temperature drying oven. The glass dish containing the first mixture is then placed in the constant temperature drying oven and dried at a certain temperature to obtain a white powder.

[0044] S3. Add the white powder to the polyurethane, then add ethyl acetate dropwise to dissolve the white powder in the polyurethane, thus obtaining a second mixture;

[0045] Specifically, the white powder is mixed evenly with polyurethane, and then ethyl acetate is added dropwise to make the white powder and polyurethane miscible, thus obtaining a second mixture.

[0046] S4. Vacuum the second mixture and heat it at 50~80°C, preferably 60°C, until the second mixture is cured to obtain PU-3F-Li conductive polyurethane composite material.

[0047] Specifically, the second mixture is evacuated to remove air bubbles, and the purpose of heating the second mixture is to increase the curing speed of the second mixture, so that the second mixture can be cured quickly to obtain PU-3F-Li conductive polyurethane composite material.

[0048] After obtaining the PU-3F-Li conductive polyurethane composite material, its performance was tested after standing for 12 hours. This is because the internal structure of the PU-3F-Li conductive polyurethane composite material is most stable at this time, avoiding inaccurate testing due to excessively long placement time.

[0049] In this embodiment, the polyurethane is a two-component polyurethane;

[0050] The two-component polyurethane includes polyurethane A, which is used as a polyurethane main agent; and polyurethane B, which is used as a polyurethane curing agent.

[0051] The weight ratio of polyurethane A to polyurethane B is 1:1.

[0052] Specifically, the source of polyurethane component A is as follows: Figure 1 Material A and polyurethane material B are shown as follows: Figure 2 As shown in the figure, material B should be mixed with material A and used immediately.

[0053] In this embodiment, the weight ratio of polyurethane A, polyurethane B, β-cyclodextrin, and 3F-Li is 19:19:1:1.

[0054] The above weight ratio yields the best-performing PU-3F-Li conductive polyurethane composite material.

[0055] In this embodiment, in step S3, the white powder is first added to the polyurethane A material, then the ethyl acetate is added dropwise. After the white powder dissolves in the polyurethane A material, the polyurethane B material is added and stirred evenly.

[0056] Since polyurethane component A is the main agent, the white powder is first added to the polyurethane component A, and then cured.

[0057] In this embodiment, the alcohol is 75% alcohol.

[0058] In this embodiment, the second mixture is injected into a polyethylene mold, and the polyethylene mold is placed on a heated iron plate;

[0059] A polyethylene mold is used to shape the second mixture, so that the second mixture obtains a corresponding shape. The heating plate heats the second mixture in the polyethylene mold to solidify it into a PU-3F-Li conductive polyurethane composite material.

[0060] The purpose of placing the polyethylene mold on the heating plate is to facilitate the direct heating and molding of the second mixture after it is placed in the polyethylene mold.

[0061] In this embodiment, the heating plate includes a first iron plate and a second iron plate, and a heating block is provided between the first iron plate and the second iron plate; the heating block in the middle can directly provide heat to the first iron plate and the second iron plate.

[0062] The surface of the first iron plate is covered with aluminum foil, and the bottom of the polyethylene mold is coated with petroleum jelly and placed on the first iron plate.

[0063] Aluminum foil improves heat transfer, while petroleum jelly increases lubrication and prevents the polyethylene mold from sticking to the first iron plate.

[0064] Example 2

[0065] Please see Figure 1 Although 3F-Li is commercially available, this increases production costs. To further reduce production costs and improve environmental friendliness, based on Example 1, this example discloses a method for preparing 3F-Li including the following steps:

[0066] Lithium carbonate was added to a reaction vessel, methanol was added and stirred until homogeneous. Trifluoromethanesulfonic acid was slowly added dropwise during the stirring process. The reaction temperature was room temperature. Once the trifluoromethanesulfonic acid was completely added and the material in the reaction vessel became solid, stirring was stopped. The reactants were filtered to obtain a white solid. The white solid was then placed in a vacuum drying oven to dry, yielding 3F-Li.

[0067] The method is that by mixing lithium carbonate and trifluoromethanesulfonic acid at room temperature, stirring, and filtering, the corresponding white solid can be obtained. Furthermore, lithium carbonate and trifluoromethanesulfonic acid are widely available, low in cost, and non-toxic and pollution-free, making them suitable for large-scale production and application.

[0068] In this embodiment, the molar ratio of lithium carbonate to trifluoromethanesulfonic acid is 0.5~1:2~3, preferably 1:2.

[0069] The amount of methanol added is 3-4 ml per gram of lithium carbonate, preferably 3 ml per gram of lithium carbonate.

[0070] Effect verification:

[0071] To further illustrate the properties of the conductive polyurethane rubber obtained by this invention, the following verification experiments were conducted:

[0072] The experimental instruments are shown in Table 1, and the experimental reagents are shown in Table 2.

[0073] Table 1 Main Instruments for the Experiment

[0074]

[0075] Table 2 Main reagents for the experiment

[0076]

[0077] Preparation of lithium trifluoromethanesulfonate (3F-Li)

[0078] As shown in Figure 2, 29.56 g (0.4 mol) of lithium carbonate was added to the reaction vessel, followed by 100 ml of methanol and stirring. During stirring, 120.06 g (0.8 mol) of trifluoromethanesulfonic acid was slowly added dropwise while maintaining the temperature at room temperature. The mixture was stirred for 100 minutes. After the trifluoromethanesulfonic acid was completely added, the liquid in the reaction vessel turned into a solid. Stirring was stopped, and the solid was filtered to obtain a white solid. The solid was then dried in a vacuum drying oven, weighed, and bottled for later use.

[0079] Preparation of PU-D-Li conductive polyurethane composite materials

[0080] The specific steps are as follows:

[0081] Using β-cyclodextrin as a carrier, lithium trifluoromethanesulfonate was added to the β-cyclodextrin, and then 75% medical alcohol was added as a solvent. After stirring, the lithium trifluoromethanesulfonate and β-cyclodextrin were completely miscible. The solution was then poured into a glass dish and placed in a constant temperature drying oven lined with asbestos mesh. The temperature was heated to 120°C and dried to form a white powder. This powder was then added to a certain amount of polyurethane A material, and a certain amount of ethyl acetate was added dropwise to aid dissolution. After the white powder was completely dissolved in material A, a certain amount of polyurethane B material was added and stirred evenly. After vacuuming, the prepared solution was poured into different high-density polyethylene molds and heated to 60°C to obtain PU-3F-Li conductive polyurethane composite material.

[0082] The corresponding PU-D-Li conductive polyurethane composite materials were prepared according to the following addition amounts (1-15).

[0083] The specific amounts to be added are shown in Table 3:

[0084] Table 3

[0085]

[0086] Measuring the resistance of PU-D-Li conductive polyurethane composite material

[0087] ①. Measuring surface resistance

[0088] According to the standard GB / T 31838.3, Figure 2 The copper electrodes are installed in the following manner: the instrument input terminal (red line) is connected to the ring electrode, and the instrument current output terminal (black line) is connected to the cylindrical electrode. Each solid conductive material is placed between the disk electrode and the cylindrical and ring electrodes. The surface resistance of the material is measured at 100 V with a period of 20 seconds, and the data is recorded after 6 measurements.

[0089] ②. Measuring volume resistivity

[0090] According to the standard GB / T 31838.3, Figure 3 Install the copper electrodes in the following manner. Connect the instrument input terminal (black wire) to the disk electrode and the instrument current output terminal (red wire) to the cylindrical electrode. Place each solid conductive material between the disk electrode, the cylindrical electrode, and the ring electrode. Measure the volume resistivity of the material at 100 V with a period of 20 seconds, and record the data after 6 measurements.

[0091] Data processing

[0092] ①. Calculation methods for surface resistivity and volume resistivity

[0093] GB / T 31838.3, the surface resistivity of the material is

[0094] ;

[0095] in Surface resistivity, in units of ; d 1 、d 2 These represent the diameter of the cylindrical electrode and the inner diameter of the annular electrode, in meters (m). The measured surface resistance value is expressed in Ω.

[0096] The volume resistivity of the material is

[0097] ;

[0098] in, Volume resistivity; unit: A represents the effective area of ​​the electrode, in m². 2 h is the average thickness of the sample, in meters; R x The measured volume resistivity is expressed in Ω.

[0099] ②. Thickness, surface resistivity, and volume resistivity of PU-D-Li conductive polyurethane composite materials.

[0100] The relevant data is as follows:

[0101] The thickness of the PU-D-Li conductive polyurethane composite material is shown in Table 4:

[0102] Table 4 Thickness of PU-D-Li Conductive Polyurethane Composite Material

[0103]

[0104] The surface resistivity (24h) of the PU-D-Li conductive polyurethane composite material is shown in Table 5:

[0105] Table 5 Surface resistivity of PU-3F-Li material (24h)

[0106]

[0107] The surface resistivity (72h) of the PU-D-Li conductive polyurethane composite material is shown in Table 6:

[0108] Table 6 Surface resistivity of PU-3F-Li material (72h)

[0109]

[0110] The product resistivity (24h) of PU-D-Li conductive polyurethane composite material is shown in Table 7:

[0111] Table 7. Volume resistivity of PU-3F-Li material (24h)

[0112]

[0113] The volume resistivity (72h) of the PU-D-Li conductive polyurethane composite material is shown in Table 8:

[0114] Table 8. Volume resistivity of PU-3F-Li material (72h)

[0115]

[0116] Analysis: (1) Analysis of the influence of different ionic liquids on the surface resistivity and volume resistivity of PU-D-Li conductive polyurethane composites

[0117] Table 9. Effect of 3F-Li on the surface resistivity of PU

[0118] Unit: m

[0119]

[0120] Table 10 Effect of 3F-Li on the volume resistivity of PU

[0121] Unit: m

[0122]

[0123] The measured surface resistivity and volume resistivity data of different ionic liquids on different materials were compared, and the processed results are shown in the table above.

[0124] The table above shows that:

[0125] 3F-Li exhibits a significant modifying effect on the electrical conductivity of polyurethane materials, with the best effect observed in experiment number 15, where 3F-Li increased the electrical conductivity of polyurethane materials by nearly one million times. Therefore, 3F-Li is a suitable ionic liquid for modifying the conductivity of polyurethane.

[0126] β-Cyclodextrin, as a carrier, significantly promotes the stability of ionic liquids in polyurethane materials. After long-term storage, experimental schemes with β-cyclodextrin as a carrier show more stable changes in surface resistivity and volume resistivity, with a smaller range of variation.

[0127] Based on numerical comparisons, we tentatively determined that experiment number 15 is the optimal experimental scheme.

[0128] Destructive testing

[0129] Based on the above experiments, the amount added in experiment number 15 was selected to prepare 8 PU-3F-Li conductive polyurethane composite material samples. The samples were then subjected to the following tests:

[0130] A1: Initial surface resistivity, surface resistivity after A1 failure, initial volume resistivity, and volume resistivity after A1 failure. A1 failure is achieved by immersion in water for 2 hours, and the relevant tests are performed immediately after A1 failure.

[0131] A2: Initial surface resistivity, surface resistivity after A2 damage, initial volume resistivity, and volume resistivity after A2 damage. A2 damage was achieved by treating the sample in a constant temperature drying oven for 2 hours at a temperature of 150℃. After A2 damage, the sample was removed and allowed to stand for 30 minutes before the relevant tests were performed.

[0132] Table 11 Effect of destructive testing on the surface resistivity and volume resistivity of PU-3F-Li

[0133]

[0134] As shown in Table 11, after 2 hours of immersion, the surface resistivity and volume resistivity of A1 remained essentially unchanged, indicating that the PU-3F-Li material of this invention has strong water resistance and that ionic liquids can be adsorbed into the polyurethane through β-cyclodextrin, exhibiting strong hydrophilicity.

[0135] After 2 hours of high-temperature baking, the surface resistivity and volume resistivity of A2 increased by 5-6 times, indicating that the PU-3F-Li material is not resistant to high temperatures. After placing A2 in the air for 30 minutes, its resistance value was measured and returned to the initial resistance value, indicating that the PU-3F-Li material has a strong self-healing function, which effectively overcomes the problem of poor repair performance of existing conductive polyurethane materials.

[0136] Tensile test of PU-3F-Li material

[0137] Based on the above experiments, two PU-3F-Li conductive polyurethane composite material samples were prepared using the addition amount selected in experiment number 15, labeled A3 and A4 respectively; two blank conductive polyurethane materials were prepared using experiment sequence 1, labeled Blank 1 and Blank 2 respectively. Tensile tests were performed on each sample, and the results are shown in Table 12 below:

[0138] Table 12 Maximum force and elongation in tensile tests

[0139]

[0140] As can be seen from Table 12, the elongation and maximum force N of PU-3F-Li are much better than those of the blank control, and the elongation even reaches 464.6335%, indicating that the mechanical properties of the PU-3F-Li material of the present invention are very good, which is beneficial to the processing and improvement of factory production line processes.

[0141] In summary, the ion transport mechanism in ionic liquids is complex, related to factors such as self-diffusion coefficient, viscosity coefficient, and conductivity, and involves elements such as the structure of cations and anions, hydrogen bonding, van der Waals forces, and ion transport numbers. Simultaneously, the interaction between cations and anions is a crucial factor in ion transport in ionic liquids, resulting from the combined effects of van der Waals forces and electrostatic interactions. Different cation structures lead to different interaction forces between cations and anions. With increasing alkyl chain length or molecular relative mass, van der Waals forces increase, hindering the movement of cations and anions to a greater extent, thus increasing their interaction forces, enhancing association in the ionic liquid, and relatively decreasing conductivity. Data shows that ionic liquids, as dopants, have a significant effect on reducing the resistivity of polymer materials.

[0142] 3F-Li significantly affects the electrical conductivity of polyurethane materials, and the amount of 3F-Li in the ionic liquid within the material also significantly alters the electrical conductivity. Based on subsequent destructive and tensile test results, experimental scheme 15 for PU-3F-Li was determined to be the optimal modified conductive polyurethane formulation. Specifically, the optimal mixing ratio is polyurethane component A: polyurethane component B: β-cyclodextrin: 3F-Li = 19:19:1:1.

[0143] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0144] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0145] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0146] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0147] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing conductive polyurethane rubber, characterized in that, Includes the following steps: S1. Add lithium trifluoromethanesulfonate to β-cyclodextrin, then add alcohol, stir well to make lithium trifluoromethanesulfonate and β-cyclodextrin miscible, and obtain the first mixture; S2. Place the first mixture in a constant temperature drying oven and dry it at 100~130℃ to form a white powder; S3. Add the white powder to the polyurethane, then add ethyl acetate dropwise to dissolve the white powder in the polyurethane, thus obtaining a second mixture; S4. Vacuum the second mixture and heat it at 50~80°C until it solidifies to obtain PU-3F-Li conductive polyurethane composite material.

2. The method for preparing conductive polyurethane rubber according to claim 1, characterized in that, The polyurethane is a two-component polyurethane; The two-component polyurethane includes polyurethane A, which is used as a polyurethane main agent; and polyurethane B, which is used as a polyurethane curing agent. The weight ratio of polyurethane A to polyurethane B is 1:

1.

3. The method for preparing conductive polyurethane rubber according to claim 2, characterized in that, The weight ratio of polyurethane component A, polyurethane component B, β-cyclodextrin and lithium trifluoromethanesulfonate is 19:19:1:

1.

4. The method for preparing conductive polyurethane rubber according to claim 3, characterized in that, In step S3, the white powder is first added to polyurethane A, then ethyl acetate is added dropwise. After the white powder dissolves in polyurethane A, polyurethane B is added and stirred until homogeneous.

5. The method for preparing conductive polyurethane rubber according to claim 1, characterized in that, The alcohol in question is 75% alcohol.

6. The method for preparing conductive polyurethane rubber according to claim 1, characterized in that, The second mixture is injected into a polyethylene mold, which is placed on a heated iron plate. The heating plate heats the second mixture within the polyethylene mold, causing it to solidify into a PU-3F-Li conductive polyurethane composite material.

7. The method for preparing conductive polyurethane rubber according to claim 6, characterized in that, The heating plate includes a first iron plate and a second iron plate, and a heating block is provided between the first iron plate and the second iron plate. The surface of the first iron plate is covered with aluminum foil, and the bottom of the polyethylene mold is coated with petroleum jelly and placed on the first iron plate.

8. The method for preparing conductive polyurethane rubber according to claim 1, characterized in that, The preparation method of the lithium trifluoromethanesulfonate salt includes the following steps: Lithium carbonate was added to a reaction vessel, followed by methanol and stirring until homogeneous. Trifluoromethanesulfonic acid was slowly added dropwise during the stirring process. The reaction temperature was room temperature. Once the trifluoromethanesulfonic acid was completely added and the material in the reaction vessel became solid, stirring was stopped. The reactants were filtered to obtain a white solid. The white solid was then placed in a vacuum drying oven and dried to obtain lithium trifluoromethanesulfonate.

9. The method for preparing conductive polyurethane rubber according to claim 8, characterized in that, The molar ratio of lithium carbonate to trifluoromethanesulfonic acid is 0.5~1:2~3; The amount of methanol added is 3-4 ml per gram of lithium carbonate.

10. A conductive polyurethane rubber, characterized in that, The conductive polyurethane rubber is prepared by the method for preparing conductive polyurethane rubber according to any one of claims 1 to 9.

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