Liquid crystal elastomer actuator and preparation method thereof, and robot

Abstract

The present invention provides a liquid crystal elastomer actuator and a preparation method and a robot thereof, wherein the preparation method comprises: dissolving a liquid crystal monomer, a first conductive material, a cross-linking agent, a chain extender, a photoinitiator and a catalyst in an organic solvent to obtain a reaction mixture solution, transferring the reaction mixture solution to a mold, reacting at room temperature under light-proof conditions, and after the reaction is completed, heating and drying to obtain a prepolymerized liquid crystal elastomer film; dissolving a second conductive material in an organic solvent to obtain a conductive solution, soaking the prepolymerized liquid crystal elastomer film in the conductive solution for a preset time, and then drying to obtain a liquid crystal elastomer film; and ultraviolet curing the liquid crystal elastomer film to obtain a liquid crystal elastomer actuator. The liquid crystal elastomer actuator prepared by the method provided by the present invention has relatively stable and superior electrical response and self-sensing deformation performance.

Description

Technical Field

[0001] The present invention relates to the field of liquid crystal technology, and in particular to a liquid crystal elastomer actuator, a preparation method thereof, and a robot. Background Art

[0002] Mimicking biological intelligent responses in artificial systems is a long-standing challenge that requires integrating stimulus-responsive motion and sensory feedback in robotic bodies. Currently, rigid robots have made progress in programmable control, but these rigid bodies rely on separate computational modeling and electrical actuation to achieve prescribed robotic actions, while complex computing systems, power supplies, and motors limit the miniaturization of the robot body and high levels of motion adaptability. Achieving intelligent responses in soft robots requires new design strategies that can provide tightly coupled actuation and sensing mechanisms.

[0003] As one of the most representative soft actuators, liquid crystal elastomers can achieve large and reversible deformations in a variety of environments and stimulation modes, and have important applications in artificial muscles and robots. So far, many properties of liquid crystal elastomers, such as shape deformation amplitude and driving speed, have been greatly improved. However, liquid crystal elastomers themselves cannot feedback detection signals in real time, which limits their accuracy in performing tasks. Therefore, it is necessary to add a sensing function to the actuator to accurately obtain its deformation degree, and even automatically control the actuator according to the real-time feedback signal. Liquid crystal elastomers, as a stimulus-responsive material, will produce very large and reversible deformations when subjected to external stimuli such as heat, light, and electricity. Compared with heat, light and other stimulation methods, power sources are easy to use, low cost, and suitable for insufficient lighting. In addition, electrically responsive liquid crystal elastomers can deform in response to electrical stimulation and provide real-time feedback of the deformation. Combining liquid crystal elastomers with conductive materials can cause them to deform by Joule heating. However, in the prior art, after adding conductive materials to liquid crystal elastomers, the conductivity is low, resulting in poor electrical response and self-sensing deformation performance of the prepared liquid crystal elastomer actuator; or rapid conductivity loss occurs during cyclic use, resulting in unstable electrical response and self-sensing deformation performance of the prepared liquid crystal elastomer actuator. Summary of the invention

[0004] The technical problem solved by the present invention is that in the prior art, after adding conductive materials to liquid crystal elastomers, the conductivity is low, resulting in poor electrical response and self-sensing deformation performance of the prepared liquid crystal elastomer actuator; or rapid conductivity loss occurs during cyclic use, resulting in unstable electrical response and self-sensing deformation performance of the prepared liquid crystal elastomer actuator.

[0005] To solve at least one of the above problems, the technical solution adopted by the present invention is:

[0006] A method for preparing a liquid crystal elastomer actuator, comprising:

[0007] Step S1, dissolving a liquid crystal monomer, a first conductive material, a cross-linking agent, a chain extender, a photoinitiator and a catalyst in an organic solvent to obtain a reaction mixture solution, transferring the reaction mixture solution to a mold, reacting it at room temperature in a light-proof condition, and heating and drying it after the reaction to obtain a pre-polymerized liquid crystal elastomer film;

[0008] Step S2, dissolving the second conductive material in an organic solvent to obtain a conductive solution, soaking the prepolymerized liquid crystal elastomer film in the conductive solution for a preset time, and then drying to obtain a liquid crystal elastomer film;

[0009] Step S3, performing ultraviolet light curing treatment on the liquid crystal elastomer film to obtain a liquid crystal elastomer actuator.

[0010] Preferably, the first conductive material includes at least one of carbon nanotubes, carbon black, graphite and Mxene, and the second conductive material includes at least one of carbon nanotubes, carbon black, graphite and Mxene.

[0011] Preferably, the first conductive material and the second conductive material both include carbon black and graphite.

[0012] Preferably, the mass ratio of the graphite to the carbon black in the first conductive material and the second conductive material is 4-6:4-6.

[0013] Preferably, the liquid crystal monomer includes one of 2-methyl-1,4-phenylenebis(4-(3-(acryloyloxy)propoxy)benzoate) and 2-methyl-1,4-phenylenebis(4-((6-(acryloyloxy)hexyl)oxy)benzoate), the cross-linking agent includes one of pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol triacrylate and polyethylene glycol diacrylate, the chain extender includes one of 3,6-dioxa-1,8-octanedithiol and 2,2-oxybis(ethane-1-thiol), the photoinitiator includes one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and benzoin dimethyl ether, and the catalyst includes dipropylamine.

[0014] Preferably, the mass ratio of the liquid crystal monomer, the cross-linking agent and the chain extender is 25-50:1:5-8.

[0015] Preferably, the mass fraction of the cross-linking agent in the liquid crystal monomer, the cross-linking agent, the first conductive material, the chain extender, the photoinitiator and the catalyst is 1.5%.

[0016] Preferably, the ratio of the total mass of the liquid crystal monomer, the cross-linking agent and the chain extender to the mass of the first conductive material is 34-56:1.

[0017] Compared with the prior art, in the process of preparing the liquid crystal elastomer actuator, the present invention uniformly mixes the first conductive material in the reaction mixed solution before the prepolymerization reaction, so that the first conductive material is uniformly distributed in the liquid crystal elastomer film, ensuring that the prepared liquid crystal elastomer actuator has a small conductivity loss during the recycling process; after the prepolymerization reaction, the second conductive material is uniformly introduced on the surface of the prepolymerized liquid crystal elastomer film, thereby ensuring that the prepared liquid crystal elastomer actuator has a high conductivity. Therefore, compared with the prior art, the liquid crystal elastomer actuator prepared by the method provided by the present invention has a more stable and superior electrical response and self-sensing deformation performance.

[0018] The present invention also provides a liquid crystal elastomer actuator, which is manufactured using the above-mentioned method for preparing the liquid crystal elastomer actuator.

[0019] The present invention also provides a robot, comprising the liquid crystal elastomer actuator as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A process flow chart for preparing a liquid crystal elastomer actuator according to an embodiment of the present invention;

[0021] Figure 2 The resistance change of the conductive film prepared with different ratios of carbon black and graphite when the temperature rises from 40℃ to 100℃;

[0022] Figure 3 A schematic diagram of a process for preparing a liquid crystal elastomer actuator according to an embodiment of the present invention;

[0023] Figure 4 is a curve showing the change of resistance over time during the cycle test of the liquid crystal elastomer actuator prepared in the comparative example;

[0024] Figure 5 is a curve showing the change of resistance over time during the cycle test of the liquid crystal elastomer actuator prepared in Example 1;

[0025] Figure 6 Graph showing the stress-strain curve of the liquid crystal elastomer actuator prepared in Example 2-9. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0027] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention can be combined with each other. The meanings of the terms "comprising", "including", "containing", and "having" are non-restrictive, that is, other steps and other ingredients that do not affect the results can be added. The above terms cover the terms "consisting of" and "essentially consisting of". Unless otherwise specified, materials, equipment, and reagents are commercially available.

[0028] like Figure 1 As shown, an embodiment of the present invention provides a method for preparing a liquid crystal elastomer actuator, comprising:

[0029] Step S1, dissolving a liquid crystal monomer, a first conductive material, a cross-linking agent, a chain extender, a photoinitiator and a catalyst in an organic solvent to obtain a reaction mixture solution, transferring the reaction mixture solution to a mold, reacting it at room temperature in a light-proof condition, and heating and drying it after the reaction to obtain a pre-polymerized liquid crystal elastomer film;

[0030] Step S2, dissolving the second conductive material in an organic solvent to obtain a conductive solution, soaking the prepolymerized liquid crystal elastomer film in the conductive solution for a preset time, and then drying to obtain a liquid crystal elastomer film;

[0031] Step S3, performing ultraviolet light curing treatment on the liquid crystal elastomer film to obtain a liquid crystal elastomer actuator.

[0032] If conductive materials are added to the liquid crystal elastomer only before the prepolymerization reaction, then only 15% by mass of conductive materials are needed to detect very low conductivity, and the flexibility and elasticity of the liquid crystal elastomer will be greatly reduced. Introducing conductive materials into the liquid crystal elastomer only after prepolymerization, the prepared liquid crystal elastomer actuator will show rapid conductivity loss during cyclic use.

[0033] In the embodiment of the present invention, during the preparation of the liquid crystal elastomer actuator, before the prepolymerization reaction, the first conductive material is uniformly mixed in the reaction mixed solution, so that the first conductive material is uniformly distributed in the liquid crystal elastomer film, ensuring that the prepared liquid crystal elastomer actuator has a small conductivity loss during the recycling process; after the prepolymerization reaction, the second conductive material is uniformly introduced on the surface of the prepolymerized liquid crystal elastomer film, thereby ensuring that the prepared liquid crystal elastomer actuator has a high conductivity. Therefore, compared with the prior art, the liquid crystal elastomer actuator prepared by the method provided by the present invention has a more stable and superior electrical response and self-sensing deformation performance.

[0034] The liquid crystal elastomer actuator provided by the present invention has the following principles of electrical response and self-sensing deformation: by designing a circuit, a voltage is applied to the liquid crystal elastomer, and the liquid crystal elastomer generates Joule heat under the action of the voltage, causing the liquid crystal elastomer to deform. When the liquid crystal elastomer is deformed, the network of the liquid crystal elastomer polymer will become tight or loose, and the distance of the conductive material inside the liquid crystal elastomer will change, resulting in a change in the resistance of the liquid crystal elastomer. In the process of the liquid crystal elastomer deforming in response to electrical stimulation, changes in electrical signals can be observed, and the changes in electrical signals reflect the deformation of the liquid crystal elastomer.

[0035] Specifically, the first conductive material includes at least one of carbon nanotubes, carbon black, graphite and Mxene, and the second conductive material includes at least one of carbon nanotubes, carbon black, graphite and Mxene. These conductive materials have high conductivity and high electric-to-heat conversion efficiency.

[0036] In an embodiment of the present invention, both the first conductive material and the second conductive material include carbon black and graphite. The resistance of the conductive material will inevitably change with the change of temperature, so that the resistance of the prepared liquid crystal elastomer actuator will also change with the change of temperature, affecting the liquid crystal elastomer actuator's ability to sense deformation under electric drive. Therefore, it is necessary to reduce the influence of the change of the resistance of the conductive material in the liquid crystal elastomer with temperature on the ability of the liquid crystal elastomer actuator to sense deformation. In an embodiment of the present invention, both the first conductive material and the second conductive material include carbon black and graphite. Since the temperature coefficient of resistance (TCR) of graphite is positive and the temperature coefficient of resistance (TCR) of carbon black is negative, the amplitude of the change of their resistance with temperature can offset each other to a certain extent, thereby reducing the influence of temperature change on the ability of the liquid crystal elastomer actuator to sense deformation.

[0037] In an embodiment of the present invention, preferably, the mass ratio of the carbon black to the graphite in the first conductive material and the second conductive material is 4-6:4-6. A conductive film is prepared by mixing graphite and carbon black in mass ratios of 1:0 (100% graphite), 8:2 (mixed film 1), 6:4 (mixed film 2), 4:6 (mixed film 3), 2:8 (mixed film 4), and 0:1 (100% carbon black), and heating the conductive film from 40°C to 100°C. The resistance change of the conductive film during this process is detected, and the following is obtained: Figure 2 The curve diagram shown by Figure 2It can be seen that when the temperature changes from 40°C to 100°C, the resistance changes of pure graphite conductive film, mixed film 1, mixed film 2, mixed film 3, mixed film 4, and pure carbon black conductive film are 12.2%, 7.3%, 4.2%, 1.7%, -3.4%, and -6.3%, respectively. When the mass ratio of graphite to carbon black is 4:6, the amplitude of the resistance change of the conductive film with temperature is the smallest, which is 1.7%. This shows that when the mass ratio of graphite to carbon black is 4:6, adding it as a conductive material to the liquid crystal elastomer can better reduce the influence of temperature change on the ability of the liquid crystal elastomer actuator to sense deformation, thereby further improving the ability of the liquid crystal elastomer actuator to sense deformation.

[0038] In an embodiment of the present invention, in the step S1, the liquid crystal monomer includes one of 2-methyl-1,4-phenylene bis(4-(3-(acryloxy)propoxy)benzoate) (RM257) and 2-methyl-1,4-phenylene bis(4-((6-(acryloxy)hexyl)oxy)benzoate) (RM82), and the cross-linking agent includes one of pentaerythritol tetrakis(3-mercaptopropionate) (PETMP), pentaerythritol triacrylate (PETA) and polyethylene glycol diacrylate (PEGDA). The chain extender includes one of 3,6-dioxa-1,8-octanedithiol (EDDET) and 2,2-oxybis(ethane-1-thiol) (DMDE), the photoinitiator includes one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (HHMP) and benzoin dimethyl ether (I-651), the catalyst includes dipropylamine (DPA), and the organic solvent used to prepare the reaction mixed solution includes one of toluene, chloroform, dichloromethane and N,N-dimethylformamide (DMF).

[0039] In an embodiment of the present invention, in order to further optimize the flexibility and elasticity of the liquid crystal elastomer actuator, in the step S1, the mass ratio of the liquid crystal monomer, the cross-linking agent and the chain extender is 25-50:1:5-8.

[0040] In an embodiment of the present invention, in step S1, when the mass fraction of the crosslinking agent in the liquid crystal monomer, the crosslinking agent, the first conductive material, the chain extender, the photoinitiator and the catalyst is 1.5%, the liquid crystal elastomer actuator exhibits better flexibility and elasticity.

[0041] In an embodiment of the present invention, in order to further improve the electrical response and self-sensing deformation performance of the liquid crystal elastomer actuator, in step S1, the ratio of the total mass of the liquid crystal monomer, the cross-linking agent and the chain extender to the mass of the first conductive material is 34-56:1.

[0042] In an embodiment of the present invention, in step S1, in order to further optimize the efficiency of synthesizing the liquid crystal elastomer film, the ratio of the total mass of the liquid crystal monomer, the cross-linking agent and the chain extender, the mass of the photoinitiator and the mass of the catalyst is 1000:120:1.

[0043] In the embodiment of the present invention, in the step S1, the reaction time is 12 hours. Setting the reaction time to 12 hours is conducive to the full progress of the reaction.

[0044] In the embodiment of the present invention, in the step S1, the drying temperature is 85°C and the drying time is 24 hours, which is conducive to fully removing the solvent in the pre-polymerized liquid crystal elastomer film.

[0045] In an embodiment of the present invention, in step S2, the organic solvent includes one of toluene, chloroform, dichloromethane and N,N-dimethylformamide (DMF).

[0046] In an embodiment of the present invention, in the step S2, the concentration of the conductive solution is 5 mg / mL, the preset time is 6 hours, and the drying is performed at room temperature in air for 6 hours.

[0047] In the embodiment of the present invention, in step S2, the wavelength of ultraviolet light used in the ultraviolet curing process is 365nm, and the processing power of ultraviolet light is 50mW / cm 2 , the treatment time is 30min. This is conducive to better curing of the liquid crystal elastomer film.

[0048] An embodiment of the present invention further provides a robot, comprising the liquid crystal elastomer actuator as described above.

[0049] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually based on the conditions recommended by the manufacturer. Figure 3 Schematic diagram of the process of preparing a liquid crystal elastomer actuator in an embodiment of the present invention.

[0050] Example 1

[0051] 1.1. Take 2 g of liquid crystal monomer RM257 and add it into a brown sample bottle, and add 0.523 g of toluene to dissolve it. Put the brown sample bottle into an oven at 85° C. for 30 min to completely dissolve the liquid crystal monomer RM257 to obtain a liquid crystal monomer solution.

[0052] 1.2. Add 0.028 g of graphite, 0.042 g of carbon black, 0.08 g of crosslinking agent PETMP, 0.64 g of chain extender EDDET, 0.022 g of photoinitiator HHMP, 0.0027 g of catalyst DPA and 0.135 g of toluene to the liquid crystal monomer solution to obtain a reaction mixed solution.

[0053] 1.3. Place the reaction mixture in a vacuum drying oven for 1 min to remove bubbles caused by mixing, transfer the solution to a square polytetrafluoroethylene (PFTE) mold with a thickness of 1 mm, and react at room temperature for 12 h. After the reaction is completed, dry it in an oven at 85°C for 24 h to obtain a pre-polymerized liquid crystal elastomer film.

[0054] 1.4. Dissolve 0.02 g of graphite and 0.03 g of carbon black in 10 mL of toluene to obtain a conductive solution. Perform ultrasonic dispersion treatment on the conductive solution for 20 minutes. Soak the prepared pre-polymerized liquid crystal elastomer film in the conductive solution for 6 hours. After soaking, take out the solution with a pipette and dry it in the air for 6 hours. After drying, use tape or cotton swab to gently clean excess conductive particles on the surface to obtain a liquid crystal elastomer film.

[0055] 1.5. Use a 50g weight to hang on the liquid crystal elastomer film for 2 hours to orient the liquid crystal elastomer film. At the same time, use ultraviolet light with a wavelength of 365nm to cure the liquid crystal elastomer film to obtain a liquid crystal elastomer actuator. The curing power of the ultraviolet light is 50mW / cm 2 , curing time 30min.

[0056] Example 2

[0057] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.011 g.

[0058] Example 3

[0059] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.015 g.

[0060] Example 4

[0061] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.019 g.

[0062] Example 5

[0063] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.023 g.

[0064] Example 6

[0065] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.027 g.

[0066] Example 7

[0067] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.031 g.

[0068] Example 8

[0069] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.035 g.

[0070] Example 9

[0071] The difference from Example 1 is that the mass of the cross-linking agent PETMP added to the liquid crystal monomer solution is 0.039 g.

[0072] Comparative Example

[0073] A1. Take 2 g of liquid crystal monomer RM257 and add it into a brown sample bottle, and add 0.523 g of toluene to dissolve it. Put the brown sample bottle into an oven at 85° C. for 30 min to completely dissolve the liquid crystal monomer RM257 to obtain a liquid crystal monomer solution.

[0074] A2. Add 0.028 g of graphite, 0.042 g of carbon black, 0.08 g of crosslinking agent PETMP, 0.64 g of chain extender EDDET, 0.022 g of photoinitiator HHMP, 0.0027 g of catalyst DPA and 0.135 g of toluene to the liquid crystal monomer solution to obtain a reaction mixed solution.

[0075] A3. Place the reaction mixture in a vacuum drying oven for 1 min to remove bubbles caused by mixing, transfer the solution to a square polytetrafluoroethylene (PFTE) mold with a thickness of 1 mm, and react at room temperature for 12 h. After the reaction is completed, dry it in an oven at 85°C for 24 h to obtain a pre-polymerized liquid crystal elastomer film.

[0076] A4. Use a 50g weight to hang on the pre-polymerized liquid crystal elastomer film for 2 hours to orient the pre-polymerized liquid crystal elastomer film. At the same time, use ultraviolet light with a wavelength of 365nm to cure the pre-polymerized liquid crystal elastomer film to obtain a liquid crystal elastomer actuator. The curing power of the ultraviolet light is 50mW / cm 2 , curing time 30min.

[0077] Experimental example

[0078] The liquid crystal elastomer actuators prepared in Example 1 and the comparative example were subjected to a cycle stability test. The test results are as follows: Figure 4 (Comparative Example) and Figure 5 As shown in (Example 1), from Figure 4 and Figure 5 It can be seen that the liquid crystal elastomer actuator prepared in the comparative example has a significantly longer cycle period after 10 cycles, and the cycle stability of the liquid crystal elastomer actuator is poor; the liquid crystal elastomer actuator prepared in Example 1 has no significant change in cycle period after more than 100 cycles, and can still work stably, and the cycle stability of the liquid crystal elastomer actuator is good. It can be seen that in the comparative example, the conductive material is added to the liquid crystal elastomer only before the prepolymerization reaction, and the cycle stability of the prepared liquid crystal elastomer actuator is better than that in Example 1, the conductive material is added to the liquid crystal elastomer before and after the prepolymerization reaction.

[0079] The liquid crystal elastomer actuator prepared in Example 2-9 was subjected to a tensile test, and the stress-strain curve was obtained as shown in FIG. Figure 3 As shown by Figure 6 It can be seen that when the mass fraction of the crosslinker in the liquid crystal monomer, the crosslinker, the first conductive material, the chain extender, the photoinitiator and the catalyst is 1.5% (Example 2), the elongation at break of the liquid crystal elastomer is 327%, and when the mass fraction of the crosslinker in the liquid crystal monomer, the crosslinker, the first conductive material, the chain extender, the photoinitiator and the catalyst increases to 5.0% (Example 9), the elongation at break decreases to 104%. It can be seen that when the mass fraction of the crosslinker in the liquid crystal monomer, the crosslinker, the first conductive material, the chain extender, the photoinitiator and the catalyst is 1.5%, the liquid crystal elastomer actuator exhibits better flexibility and elasticity. It should be noted that in Examples 2-9, the mass fractions of the crosslinker in the liquid crystal monomer, the crosslinker, the first conductive material, the chain extender, the photoinitiator and the catalyst are 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% and 5.0%, respectively.

[0080] In addition, it should be noted that although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A method for preparing a liquid crystal elastomer actuator, characterized in that: include: Step S1, dissolving a liquid crystal monomer, a first conductive material, a cross-linking agent, a chain extender, a photoinitiator and a catalyst in an organic solvent to obtain a reaction mixture solution, transferring the reaction mixture solution to a mold, reacting it at room temperature in a light-proof condition, and heating and drying it after the reaction to obtain a pre-polymerized liquid crystal elastomer film; Step S2, dissolving the second conductive material in an organic solvent to obtain a conductive solution, soaking the prepolymerized liquid crystal elastomer film in the conductive solution for a preset time, and then drying to obtain a liquid crystal elastomer film; Step S3, performing ultraviolet light curing treatment on the liquid crystal elastomer film to obtain a liquid crystal elastomer actuator; Among them, the first conductive material and the second conductive material are both carbon black and graphite; the mass ratio of the graphite and the carbon black in the first conductive material and the second conductive material is 4-6:4-6; the liquid crystal monomer includes one of 2-methyl-1,4-phenylene bis(4-(3-(acryloyloxy)propoxy)benzoate) and 2-methyl-1,4-phenylene bis(4-((6-(acryloyloxy)hexyl)oxy)benzoate).

2. The method for preparing a liquid crystal elastomer actuator according to claim 1, characterized in that: The cross-linking agent includes one of pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol triacrylate and polyethylene glycol diacrylate, the chain extender includes one of 3,6-dioxa-1,8-octanedithiol and 2,2-oxybis (ethane-1-thiol), the photoinitiator includes one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and benzoin dimethyl ether, and the catalyst includes dipropylamine.

3. The method for preparing a liquid crystal elastomer actuator according to claim 1, characterized in that: The mass ratio of the liquid crystal monomer, the cross-linking agent and the chain extender is 25-50:1:5-8.

4. The method for preparing a liquid crystal elastomer actuator according to claim 3, characterized in that: In the step S1, the mass fraction of the cross-linking agent in the total mass of the liquid crystal monomer, the cross-linking agent, the first conductive material, the chain extender, the photoinitiator and the catalyst is 1.5%.

5. The method for preparing a liquid crystal elastomer actuator according to claim 3, characterized in that: The ratio of the total mass of the liquid crystal monomer, the cross-linking agent and the chain extender to the mass of the first conductive material is 34-56:

1.

6. A liquid crystal elastomer actuator, characterized in that: The liquid crystal elastomer actuator is prepared by the preparation method of any one of claims 1 to 5.

7. A robot, characterized in that: Comprising the liquid crystal elastomer actuator as claimed in claim 6.

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