Synthesis and application of hyperbranched pyrrole-based photothermal agent with ultraviolet and near-infrared dual photothermal effects

Abstract

The invention discloses synthesis and application of a hyperbranched pyrrole-based photothermal agent with ultraviolet and near-infrared dual photothermal effects, and relates to the technical field of functional polymer materials. The method comprises the following steps: forming a 1, 3-dipole from a bifunctional isocyanide monomer under the assistance of inorganic alkali, and carrying out cycloaddition polymerization reaction on the 1, 3-dipole and trifunctional acetylenic ketone in a third organic solvent under the action of a copper catalyst to obtain the hyperbranched pyrrolyl photo-thermal agent with ultraviolet and near-infrared dual photo-thermal effects. The photosensitizer prepared by the invention can realize a photothermal effect under the irradiation of an ultraviolet / near-infrared wide-spectrum light source no matter in an aggregation state or a dispersion state; after the photo-thermal agent is compounded with a liquid crystal elastomer, the liquid crystal elastomer can be endowed with the characteristics of ultraviolet light driving and near-infrared light driving deformation, and the potential of the photo-thermal agent in practical application is further verified through the success of application exploration.

Description

Technical Field

[0001] The present invention relates to the technical field of functional polymer materials, and specifically relates to the synthesis and application of a hyperbranched pyrrole-based photothermal agent with ultraviolet and near-infrared dual photothermal effects. Background Art

[0002] The photothermal effect is an effect that can absorb light energy of a specific wavelength and convert the light energy into heat energy. In the field of functional materials, materials with photothermal effects have high application value in the fields of biology and intelligent materials, such as seawater desalination, photothermal therapy, photothermal drive, photothermal catalysis, etc. However, at present, there are few polymers that can simultaneously have an intrinsic photothermal effect on ultraviolet light and near-infrared light without additional doping of photothermal agents. The current research on such photothermal materials with broad spectral effects mainly focuses on carbon-based materials such as carbon nanotubes, graphene, graphene oxide; metal nanoparticles, transition metal dichalcogenides, rare earth doping, MXene, etc. Although dual photothermal responsiveness can be achieved by compounding with metal nanoparticles, after compounding, the stability of the polymer material and the compatibility of the system face great challenges. Therefore, the design and synthesis of polymers with intrinsic dual photothermal responses have important research value and application potential. Therefore, it has important research value and application potential to synthesize a polymer with broad-spectrum ultraviolet and near-infrared dual photothermal effects by an efficient and simple method in one step.

[0003] Pyrrole is an electron-rich five-membered nitrogen heterocyclic compound, in which the lone pair of electrons on the nitrogen participates in the conjugation of the aromatic heterocycle. Therefore, the conjugation degree of the entire pyrrole plane is the highest among nitrogen heterocyclic compounds such as pyridine and imidazole. The special conjugated structure of pyrrole can form good electron coupling with other molecules, enhance light absorption and photothermal conversion, and thus has better light absorption and light conversion capabilities. Therefore, many dye molecules can greatly improve their photophysical properties by introducing pyrrole units into the molecular system through molecular structure design, such as commercial BODIPY dyes, etc. Hyperbranched is a kind of polymer material with a three-dimensional branched structure. Its special three-dimensional spatial configuration gives it a higher surface area and porosity, and has a higher degree of freedom in molecular design. Therefore, hyperbranched polymers have better light absorption ability and higher photothermal conversion efficiency compared to linear polymers with the same repeating units.

[0004] At present, the preparation of polymers with simultaneous ultraviolet and near-infrared photothermal conversion requires complex structural design of materials, such as introducing light-absorbing units into the polymer backbone, or performing post-modification of functional units, or doping carbon-based materials with high photothermal conversion characteristics, metal sulfides, etc. It is still a great challenge to achieve non-doped and one-step simple synthesis of polymer materials with ultraviolet and near-infrared dual photothermal conversion capabilities. Summary of the Invention

[0005] Aiming at the deficiencies existing in the above-mentioned background technology, the present invention provides a synthesis and application of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects. This synthesis method synthesizes the hyperbranched pyrrolyl photothermal agent through alkynylation, cycloaddition, and one-step copper catalysis. The reaction method has high universality and strong atom economy, without post-modification and doping, and the post-treatment operation is simple. The photosensitizer prepared by the present invention can achieve photothermal effects under the irradiation of ultraviolet / near-infrared broadband light sources regardless of the aggregated state or the dispersed state; after being compounded with liquid crystal elastomers, this photothermal agent can endow the liquid crystal elastomers with the characteristics of ultraviolet light-driven and near-infrared light-driven deformation, and the success of this application exploration further verifies the potential of this photothermal agent in practical applications.

[0006] The first object of the present invention is to provide a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects. The structural general formula of the hyperbranched pyrrolyl photothermal agent is shown in formula (III): (III) In the formula, A is phenyl or triphenylamine, and n = 2 - 8.

[0007] Preferably, the weight-average molecular weight of the hyperbranched pyrrolyl photothermal agent is 30,000 - 70,000 (g / mol), and the molecular weight distribution is 1.78 - 5.48.

[0008] The second object of the present invention is to provide a preparation method of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects, including the following steps: React 1,1,1-benzenetricarbaldehyde with an alkynylation reagent in a first organic solvent at a low temperature of -10 to -5 °C for 1.5 - 3 h, then raise the temperature to room temperature, stir for 5 - 10 h, perform an oxidation reaction with an oxidant, and then separate to obtain a trifunctional alkynone monomer by column chromatography; Hydrolyze isocyanoacetate and then couple it with a dibromo halohydrocarbon in a second organic solvent to obtain a difunctional isocyanide monomer; Form a 1,3-dipole from the difunctional isocyanide monomer with the assistance of an inorganic base, and perform a cycloaddition polymerization reaction with the trifunctional alkynone in a third organic solvent under the action of a copper catalyst to obtain a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects.

[0009] Preferably, the structural general formula of the trifunctional alkynone is shown in formula (I): (I) The structural general formula of the difunctional isocyanide monomer is shown in formula (II): (II) In formulas (I) and (II), A is phenyl or triphenylamine; m = 3 - 10.

[0010] Preferably, the first organic solvent is tetrahydrofuran and / or diethyl ether; the second organic solvent is one or more of N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone; the third organic solvent is one or more of N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone; The oxidant is one or more of 2-iodoxybenzoic acid, manganese dioxide, and chromium trioxide; The copper catalyst is one or more of cuprous iodide, copper oxide, cuprous bromide, copper acetate, and cuprous chloride; The inorganic base is one or more of potassium acetate, sodium acetate, potassium carbonate, and sodium carbonate.

[0011] The third object of the present invention is to provide an application of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects in a light-controlled actuator or photothermal conversion.

[0012] The fourth object of the present invention is to provide a preparation method of a hyperbranched liquid crystal actuator, comprising the following steps: Dissolve a liquid crystal monomer, a chain extender, a crosslinking agent, and a thioester in N,N-dimethylformamide to obtain a liquid crystal system; Blend a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects with the liquid crystal system at room temperature to obtain a mixed solution; Place the mixed solution in a mold and react at 75 - 85 °C for 12 - 48 h to obtain an elastomeric film; Among them, the chain extender is dithiol; the crosslinking agent is tetrathiol; the liquid crystal monomer is RM82.

[0013] Preferably, programming endowment of the elastomeric film includes: Perform secondary crosslinking on the elastomeric film through the solvent ethylenediamine or cystamine, and construct a crosslinking gradient difference on the film surface by using different amounts of chemical crosslinking, and generate driving forces of different magnitudes by using the gradient difference.

[0014] The fifth object of the present invention is to provide a hyperbranched liquid crystal actuator.

[0015] The sixth object of the present invention is to provide an application of a hyperbranched liquid crystal actuator in the field of light driving.

[0016] Compared with the prior art, the beneficial effects of the present invention are: Synthesis and application of a hyperbranched pyrrolyl-based photothermal agent with dual ultraviolet and near-infrared photothermal effects provided by the present invention. The raw materials of the preparation method of the present invention are cheap and easily available, and can be directly purchased or prepared through simple reactions. The reaction is simple, efficient, with simple post-treatment and less waste. Hyperbranched pyrrolyl-based polymers with different chain lengths can be efficiently synthesized in one step. The reaction conditions of the present invention are mild, the substrate range is wide, the structure of the obtained polymer is clear, the yield is high, it conforms to atom economy, and is easy to scale up production.

[0017] The polymer prepared by the present invention can achieve dual ultraviolet and near-infrared photothermal effects in the aggregated state (solid) and dispersed state (liquid), and this broad-spectrum response does not require additional doping of carbon materials, wrapping in metal nanoparticles, or post-modification of the polymer to introduce other photosensitive moieties or dyes to achieve the intrinsic dual ultraviolet and near-infrared photothermal effects of the polymer.

[0018] The photothermal agent prepared by the present invention is blended with a liquid crystal elastomer to realize the application of a light-controlled actuator. And the stability of the photosensitizer is tested. Under multiple irradiations, it can still well achieve photothermal conversion and light-controlled driving performance. Good photothermal effects and applications are achieved.

[0019] The preparation method provided by the present invention mainly involves reacting 1,1',1''-(benzene-1,3,5-triyl)trifunctional alkynone with a binary isocyanatoester at 60-100 °C for 12 hours under the action of a catalyst to complete a polycycloaddition reaction to obtain a pyrrolyl-based photosensitizer with a branched structure. The prepared photosensitizer can achieve photothermal effects under irradiation with a broad-spectrum light source regardless of whether it is in the aggregated state or the dispersed state. For example, it has good photothermal conversion ability under irradiation with ultraviolet light at 365 nm and near-infrared light at 808 nm. When irradiating the photothermal agent solution with a 365 nm ultraviolet light source, when irradiated with a light intensity of 0.5 W / cm 2 the temperature can quickly reach 75 °C in 300 seconds. When irradiating the solid of this photothermal agent with a light intensity of 0.3 W / cm 2 it only takes 20 seconds for the surface temperature to reach 110 °C. Similarly, when irradiating this photosensitizer with an 808 nm near-infrared light source, when irradiated with a light intensity of 2.0 W / cm 2When irradiating the photothermal agent solution with light of a certain light intensity, it can quickly reach 62 degrees in 300 seconds. In the present invention, a series of hyperbranched pyrrolyl polymers are synthesized by using a copper-catalyzed [3+2] polycycloaddition reaction. Due to the special 3D branched structure of the hyperbranched polymer and the molecular cavities generated by the branching, the light absorption ability is greatly improved. In addition, the increased specific surface area due to the branching further enhances the light absorption and refraction abilities. In addition, by designing a molecular structure with both rigidity and flexibility, this photothermal agent can dissipate the absorbed light energy in the form of heat through the molecular motion of the flexible chain segments, thereby realizing the dual photothermal conversion ability for ultraviolet and near-infrared light, especially having a fast and efficient photothermal conversion ability for ultraviolet light. In addition, after this photothermal agent is compounded with a liquid crystal elastomer, by utilizing the intrinsic thermally driven characteristics of the liquid crystal elastomer, 1-2 wt% of this photothermal agent is doped into the liquid crystal elastomer. By using the photothermal conversion ability of this photothermal agent, the absorbed light energy is converted into heat energy, thereby activating the thermally driven performance of the liquid crystal elastomer and endowing the liquid crystal elastomer with the characteristics of ultraviolet light-driven and near-infrared light-driven deformation. The success of this application exploration further verifies the potential of this photothermal agent in practical applications. Description of the Drawings

[0020] Figure 1 1H NMR spectrum of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application in deuterated dimethyl sulfoxide.

[0021] Figure 2 13C NMR spectrum of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application in deuterated dimethyl sulfoxide.

[0022] Figure 3 Fourier transform infrared spectrum of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application compared with the monomer.

[0023] Figure 4 UV 365 nm temperature-time photothermal curve of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application.

[0024] Figure 5 Near-infrared 808 nm temperature-time photothermal curve of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application.

[0025] Figure 6 UV photothermal stability cycle diagram of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application.

[0026] Figure 7 Near-infrared photothermal stability cycle diagram of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 of this application.

[0027] Figure 8 UV-visible near-infrared performance diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 1 of this application.

[0028] Figure 9 UV light photothermal driving diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 1 of this application.

[0029] Figure 10 Near-infrared light photothermal driving diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 1 of this application.

[0030] Figure 11 Nitrogen adsorption specific surface area diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 1 of this application.

[0031] Figure 12 Scanning electron microscope image of the hyperbranched pyrrolyl photothermal agent prepared in Example 1 of this application.

[0032] Figure 13 Polymerization reaction mechanism diagram of this photothermal agent. Detailed implementation manners

[0033] In order to enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention will be further described below in conjunction with specific embodiments and the accompanying drawings. However, the specific embodiments cited do not limit the present invention.

[0034] The purpose of the present invention is to provide a synthesis method of a hyperbranched structural photothermal agent with ultraviolet and near-infrared photothermal effects with broad-spectrum light response. This synthesis method synthesizes a hyperbranched pyrrolyl photothermal agent through alkynylation, cycloaddition, and copper-catalyzed one-step synthesis. The reaction method has high generality, strong atom economy, no need for post-modification and doping, and simple post-treatment operations.

[0035] Another purpose of the present invention is to overcome the defect that existing photothermal polymers only respond to narrow spectra, avoid using dyes and inorganic carbon materials for doping, and simply synthesize a polymer material with ultraviolet and near-infrared dual photothermal effects that can achieve broad-spectrum multi-function integration without additional polymer post-modification. The photothermal agent synthesized by the present invention can be doped with liquid crystal elastomers to endow the liquid crystal monomers with the characteristics of light-controlled driving, and endow the liquid crystal elastomers with better spatio-temporal manipulability.

[0036] In order to achieve the above purpose, the first aspect of the present invention provides a hyperbranched pyrrolyl photothermal agent with ultraviolet and near-infrared dual photothermal effects. The structural general formula of the hyperbranched pyrrolyl photothermal agent is shown in Formula (III): (III) In the formula, A is phenyl or triphenylamine, and n = 2 - 8.

[0037] Among them, the weight-average molecular weight of the hyperbranched pyrrolyl photothermal agent is 30,000 to 70,000 (g / mol), and the molecular weight distribution is 1.78 to 5.48.

[0038] The second aspect of the present invention provides a preparation method of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects, comprising the following steps: React 1,1,1-benzenetricarbaldehyde with an alkynylation reagent at -10°C in a first organic solvent for 2 hours, then raise the temperature to room temperature and stir for 6 hours. After the reaction ends, perform a low-temperature reaction. After the reaction ends, add an oxidant IBX (2-iodoxybenzoic acid) and stir overnight under reflux in ethyl acetate to obtain an oxidized trifunctional alkynone monomer; Hydrolyze commercially available isocyanoacetate and perform a coupling reaction with a dibromo halohydrocarbon in a second organic solvent, DMF (N,N-dimethylformamide), and stir at 60°C for 7 hours to obtain a difunctional isocyanide monomer; Form a 1,3-dipole from the difunctional isocyanide monomer with the assistance of an inorganic base, and perform a cycloaddition polymerization reaction with the trifunctional alkynone in a third organic solvent under the action of a copper catalyst. The polymerization conditions are to use 4 mL of N-methylpyrrolidone, 10% mmol of copper iodide, and 4 mmol of potassium acetate, and stir and react at 60°C for 12 hours. After the reaction ends, use the precipitation method and freeze-dry to remove excess impurities to obtain a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects. The reaction mechanism is as Figure 13 shown.

[0039] Among them, the structural general formula of the trifunctional alkynone is as shown in formula (I): (I) The structural general formula of the difunctional isocyanide monomer is as shown in formula (II): (II) In formula (I) and (II), A is phenyl or triphenylamine; m = 3 to 10.

[0040] The first organic solvent is tetrahydrofuran and / or diethyl ether; the second organic solvent is one or more of N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone; the third organic solvent is one or more of N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0041] The oxidant is one or more of 2-iodoxybenzoic acid, manganese dioxide, and chromium trioxide; The copper catalyst is one or more of cuprous iodide, copper oxide, cuprous bromide, copper acetate, and cuprous chloride; The inorganic base is one or more of potassium acetate, sodium acetate, potassium carbonate, and sodium carbonate.

[0042] The dosage ratio of 1,1,1 - phenyl - 1,3,5 - benzenecarbaldehyde to the alkynylation reagent is 1:10 equiv; The ratio of commercial isocyanoacetate to dibromo - halohydrocarbon is 1:2.5 equiv; The molar ratio of trifunctional alkynone, difunctional isocyanide, inorganic base, and copper catalyst is 1:2:2:0.1.

[0043] Exemplarily, a synthesis method of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet - near - infrared photothermal effects includes: (1) 1,1,1 - phenyl - 1,3,5 - benzenecarbaldehyde and an alkynylation reagent are reacted at low temperature in an organic solvent and then oxidized by an oxidant to obtain a trifunctional alkynone monomer.

[0044] (2) The difunctional isocyanide monomer is obtained by coupling isocyanoacetate after hydrolysis with dibromo - halohydrocarbon in an organic solvent.

[0045] (3) The difunctional isocyanide monomer forms a 1,3 - dipole with the assistance of an inorganic base and undergoes a cycloaddition polymerization reaction with the trifunctional alkynone in a third organic solvent under the action of a copper catalyst to obtain a pyrrolyl polymer with a hyperbranched structure having ultraviolet / near - infrared photothermal effects.

[0046] The organic solvent in step (1) is one of tetrahydrofuran and diethyl ether, preferably tetrahydrofuran; the oxidant is at least one of 2 - iodoxybenzoic acid, manganese dioxide, and chromium trioxide, preferably 2 - iodoxybenzoic acid.

[0047] The organic solvent in step (2) is one or more of N,N - dimethylformamide, dimethyl sulfoxide, N,N - dimethylacetamide, N - methylpyrrolidone, and preferably N,N - dimethylformamide.

[0048] The organic solvent in step (3) is one or more of N,N - dimethylformamide, dimethyl sulfoxide, N,N - dimethylacetamide, N - methylpyrrolidone, and preferably N - methylpyrrolidone; the copper catalyst is at least one of cuprous iodide, copper oxide, cuprous bromide, copper acetate, and cuprous chloride, preferably cuprous iodide.

[0049] The monomers obtained in steps (1) - (2) need to be separated and purified by silica gel column chromatography.

[0050] After the polymerization reaction in step (3), at least one of diethyl ether, acetone, tetrahydrofuran, and n-hexane is used as a precipitant for precipitation purification, preferably diethyl ether; after purification, a freeze dryer is used to freeze-dry and remove the solvent in the polymer at a low temperature.

[0051] The third aspect of the present invention provides an application of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects in a light-controlled actuator or photothermal conversion.

[0052] Exemplarily, the hyperbranched pyrrolyl photothermal agent is dissolved in at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N-methylpyrrolidone, preferably dimethyl sulfoxide, to obtain a photothermal agent solution; Take 100 μL of the photothermal agent solution with a concentration of 20 μg / mL to 50 μg / mL, and use ultraviolet light with different intensities, a wavelength of 365 nm, and a light power intensity of 100 mW / cm 2 ~ 800 mW / cm 2 , and observe the change of the solution temperature with time under the detection of an infrared thermal imager.

[0053] Take 100 μL of the photothermal agent solution with a concentration of 20 μg / mL to 50 μg / mL, and use a near-infrared light source with different intensities, a wavelength of 808 nm, and a light power intensity of 100 mW / cm 2 ~ 1000 mW / cm 2 , and observe the change of the solution temperature with time under the detection of an infrared thermal imager.

[0054] Take 5-20 mg of the solid photothermal agent and spread it on a glass slide, irradiate the photothermal agent with the light source and light intensity of claims 7 and 8, and use an infrared thermal imager to detect the surface temperature of the sample.

[0055] The fourth aspect of the present invention provides a preparation method of a hyperbranched liquid crystal actuator, including the following steps: Dissolve a liquid crystal monomer, a commercial chain extender, a crosslinking agent, and a thioester in N,N-dimethylformamide to obtain a liquid crystal mixture system; Blend a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects with the liquid crystal mixture system at room temperature to obtain a mixed solution; Place the mixed solution in a mold and react at 75-85 °C for 12-48 h to obtain an elastomer film; Among them, the chain extender is dithiol; the crosslinking agent is tetrathiol; the liquid crystal monomer is RM82.

[0056] Exemplarily, a preparation method of a hyperbranched liquid crystal actuator includes: Step (1): Weigh 1-2 wt% of the hyperbranched photothermal agent and dissolve it in 2-3 mL of N,N-dimethylformamide.

[0057] Step (2): Mix the liquid crystal monomer RM82 with the commercial chain extender dithiol, crosslinker tetrathiol, and thiolactone evenly in 5 mL of N,N-dimethylformamide.

[0058] Step (3): Blend the hyperbranched photothermal agent provided by the present invention with the liquid crystal system described in step (2) evenly at room temperature.

[0059] Pour the above mixed solution into a tetrafluoro mold, place it in an 80 °C oven, and react for 24 hours. By the solvent evaporation method, after the solvent has evaporated, use tweezers to demold the obtained elastomer film from the tetrafluoro mold.

[0060] Programming endowment is carried out on the elastomer film, including: Perform secondary crosslinking on the elastomer film through the solvent ethylenediamine / cystamine, and use different amounts of chemical crosslinking to construct a crosslinking gradient difference on the film surface, and use the gradient difference to generate driving forces of different magnitudes.

[0061] Exemplarily, programming endowment is carried out on the obtained elastomer film. Through the chemical method, the elastomer film is secondarily crosslinked with the solvent ethylenediamine, and different amounts of chemical crosslinking are used to construct a crosslinking gradient difference on the film surface, and the gradient difference is used to generate driving forces of different magnitudes, thereby realizing the light-driven characteristics.

[0062] The fifth aspect of the present invention provides a hyperbranched liquid crystal actuator.

[0063] The sixth aspect of the present invention is an application of a hyperbranched liquid crystal actuator in the field of light driving.

[0064] Exemplarily, a liquid crystal actuator with photothermal driving characteristics is used to achieve drivability under a hot stage and different light source irradiations. Three liquid crystal elastomer films are adhered together by an adhesive. Under the light intensity of ultraviolet light at 100 mW / cm 2 it can mimic the opening and closing of natural flowers. Under the near-infrared 808 nm light intensity of 2.0 W / cm 2 it can achieve bending and folding movements.

[0065] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used, unless otherwise specified, can all be purchased on the market.

[0066] Example 1 A preparation method of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects, comprising the following steps: Step 1: 1,1,1-Phenyl-1,3,5-benzenetricarbaldehyde reacts with an alkynylation reagent at low temperature in an organic solvent and is then oxidized by an oxidant to obtain a trifunctional alkynone monomer. Among them, the organic solvent is preferably tetrahydrofuran. The dosage ratio of 1,1,1-phenyl-1,3,5-benzenetricarbaldehyde to ethynylmagnesium bromide is 1:10 equiv. The reaction is carried out at -10 °C. After ethynylmagnesium bromide is added dropwise to the reaction system, the reaction flask is gradually heated to room temperature and stirred at room temperature for 6 hours. After the reaction is completed, it is extracted with ethyl acetate and the organic phase is concentrated.

[0067] Step 2: The organic phase is separated and purified by column chromatography. The obtained alkynol after purification is oxidized with an oxidant IBX (2-iodoxybenzoic acid), and the proportion of the oxidant is 5 equivalents of the obtained alkynol. It is stirred for 12 hours under the condition of refluxing ethyl acetate. After the reaction is completed, 1,3,5-trifunctional alkynone is obtained by flash column chromatography. Its property is a yellow solid with a yield of 76%. Step 3: The commercial isocyanoacetate is hydrolyzed and then undergoes a coupling reaction with a dibromo halohydrocarbon in a second organic solvent, DMF (N,N-dimethylformamide), and stirred at 60 °C for 7 hours to obtain a difunctional isocyanide monomer; the molar ratio of the commercial isocyanoacetate to the dibromo halohydrocarbon is 1:2.5 equiv, and the reaction condition is stirring at 60 °C in N,N-dimethylformamide for 7 hours. After the reaction is completed, it is separated and purified by column chromatography to obtain a white solid, which is the difunctional isocyanide monomer.

[0068] Step 4: The trifunctional alkynone, difunctional isocyanide monomer, potassium acetate, and copper(I) iodide are added to the reaction flask in a molar ratio of 1:2:2:0.1. The addition order is as follows: copper(I) iodide and potassium acetate are added to the reaction flask under nitrogen conditions, and an organic solvent is added. After the catalyst and base are completely dissolved, the reaction substrates trifunctional alkynone and difunctional isocyanide monomer are added. The reaction flask is purged with gas 3 times through a double-tube to ensure that the reaction system is in an inert air condition. The organic solvent is N-methylpyrrolidone.

[0069] Step 5: The reaction is carried out at 60 °C for 12 hours. After the reaction is completed, the obtained polymer is purified by precipitation using a 500 mL precipitant with an ether:n-hexane mixed solution in a ratio of 20:1 (volume ratio).

[0070] Step 6: The purified hyperbranched pyrrolyl polymer is freeze-dried in a freeze dryer for 2 days to remove the solvent, and the target polymer HBP-3C after removing the solvent is obtained.

[0071] Example 2 Preparation of Liquid Crystal Elastomer and Photothermal Agent Film (LCE@HBP) Step 1. The preparation experiment of the liquid crystal elastomer is carried out according to the following process. First, the crosslinking agent tetrathiols and the chain extender dithiols are dissolved in 0.5 g of N,N-dimethylformamide, and a magnetic stirrer can be added to promote stirring and mixing evenly. Then, 40 μL of triethylamine is added to the system as an initiator. The liquid crystal monomer RM82 (1,4-bis-[4-(6-acryloyloxyhexyloxy)benzoyloxy]-2-methylbenzene) is dissolved in 1 g of N,N-dimethylformamide. Then, under an inert gas condition, the hyperbranched polymer HBP-3C and the liquid crystal monomer are stirred at 80 °C under nitrogen for 8 hours.

[0072] Step 2. After 8 hours, the reaction solution in the reaction flask is poured into a tetrafluoro mold, and the mold is placed in an 80 °C oven and reacted for another 12 hours.

[0073] Step 3. After reacting for another 12 hours, the film is demolded from the tetrafluoro mold, and then the film is programmed by stretching. Different degrees of secondary crosslinking are carried out on the upper surface of the film by using cystamine, and different crosslinking gradients are constructed by controlling the dosage of the crosslinking agent.

[0074] Step 4. The film after programming and secondary crosslinking is dried at room temperature overnight.

[0075] Example 3 A synthesis method of a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects, comprising: (1) 1,1,1-benzen-1,3,5-benzenecarbaldehyde reacts with an alkynylation reagent in an organic solvent at -8 °C and is then oxidized by an oxidant to obtain a trifunctional alkynone monomer.

[0076] (2) The difunctional isocyanide monomer is obtained by hydrolysis of isocyanatoacetate and coupling with a dibromo halohydrocarbon in an organic solvent.

[0077] (3) The difunctional isocyanide monomer forms a 1,3-dipole with the assistance of potassium carbonate and undergoes a cycloaddition polymerization reaction with the trifunctional alkynone in an organic solvent under the action of a copper catalyst to obtain a hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects.

[0078] The organic solvent described in step (1) is a mixed solvent of tetrahydrofuran and diethyl ether with a volume ratio of 1:1; the oxidant is manganese dioxide.

[0079] The organic solvent described in step (2) is N-methylpyrrolidone.

[0080] The organic solvent described in step (3) is N,N-dimethylformamide; the copper catalyst is copper acetate.

[0081] The monomers obtained in steps (1) to (2) need to be separated and purified by silica gel column chromatography.

[0082] After the polymerization reaction in step (3), precipitation purification is carried out using the precipitant n-hexane; after purification, the solvent in the polymer is freeze-dried and removed at low temperature using a freeze dryer.

[0083] The dosage ratio of 1,1,1-benzen-1,3,5-benzaldehyde to the alkynylation reagent is 1:10 equiv; The ratio of isocyanoacetate to dibromo halohydrocarbon is 1:2.5 equiv; The molar ratio of trifunctional alkynone, difunctional isocyanide, potassium carbonate and copper catalyst is 1:2:2:0.1.

[0084] Example 4 Same as Example 1, except that in step 2, the proportion of the oxidant is 7 equivalents of the obtained alkynol.

[0085] Example 5 Same as Example 2, except that in step 3, ethylenediamine is used for secondary cross-linking of the upper surface of the film to different degrees.

[0086] Example 6 A preparation method of a hyperbranched liquid crystal actuator, comprising: Step (1) Weigh 1 wt% of the hyperbranched photothermal agent and dissolve it in 2 ml of N,N-dimethylformamide.

[0087] Step (2) Mix the liquid crystal monomer RM82 with the commercial chain extender dithiol, cross-linking agent tetrathiol, and thiolactone evenly with 5 ml of N,N-dimethylformamide.

[0088] Step (3) Blend the hyperbranched photothermal agent provided in Example 1 with the liquid crystal system described in step (2) evenly at room temperature.

[0089] Pour the above mixed solution into a tetrafluoro mold, place it in an oven at 75 °C, and react for 48 hours. By the solvent evaporation method, after the solvent evaporates, the obtained elastomer film is demolded from the tetrafluoro mold using tweezers.

[0090] Programming is imparted to the elastomer film, including: Programming is imparted to the obtained elastomer film. Through a chemical method, ethylenediamine is used to perform secondary cross-linking on the elastomer film, and by using different amounts of chemical cross-linking, a cross-linking gradient difference is constructed on the film surface, and different driving forces are generated using the gradient difference, thereby realizing the light-driven characteristics.

[0091] Example 7 A preparation method of a hyperbranched liquid crystal actuator, comprising: Step (1): Weigh 2 wt% of the hyperbranched photothermal agent and dissolve it in 3 mL of N,N-dimethylformamide.

[0092] Step (2): Mix the liquid crystal monomer RM82 with the commercial chain extender dithiol, crosslinker tetrathiol, and thiolactone evenly in 5 mL of N,N-dimethylformamide.

[0093] Step (3): Blend the hyperbranched photothermal agent provided in Example 1 with the liquid crystal system described in Step (2) evenly at room temperature.

[0094] Pour the above mixed solution into a tetrafluoro mold, place it in an 85-degree oven, and react for 12 hours. By the solvent evaporation method, after the solvent has evaporated, use tweezers to demold the obtained elastomer film from the tetrafluoro mold.

[0095] Programming is imparted to the elastomer film, including: Programming is imparted to the obtained elastomer film. The elastomer film is crosslinked secondarily by the chemical method using ethylenediamine as the solvent, and by using different amounts of chemical crosslinking, a crosslinking gradient difference is constructed on the film surface. Different driving forces of different magnitudes are generated using the gradient difference, thereby realizing the light-driven property.

[0096] To illustrate the relevant properties of the hyperbranched pyrrolyl photothermal agent with dual ultraviolet and near-infrared photothermal effects provided by the present invention, it is described in conjunction with the accompanying drawings.

[0097] Photothermal performance of HBP-3C Step 1: Dissolve the hyperbranched pyrrolyl polymer prepared in Example 1 in dimethyl sulfoxide to prepare a polymer solution with a molar concentration of 10 -3 Take 100 μL of this polymer solution and drop it on a glass slide, and irradiate the polymer solution with ultraviolet and near-infrared light of different light power intensities. The light power is calibrated by a light power density meter.

[0098] Step 2: Use an infrared thermal imaging camera to capture in real time the change in the surface temperature of the sample under the irradiation conditions.

[0099] Figure 1 1H NMR spectrum of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 in deuterated dimethyl sulfoxide; This figure is the NMR hydrogen spectrum data diagram for the structural characterization of the prepared hyperbranched pyrrole-based photothermal agent. As shown in the figure, the peaks at chemical shifts of δ 8.26, 7.69, and 7.23 in the aryl region are attributed to the characteristic hydrogens on pyrrole and benzene rings in the prepared hyperbranched pyrrole-based polymer. Their integral ratios are consistent with the ratio of hydrogens on pyrrole to hydrogens on benzene ring in each repeating unit of the target compound, which is 2:1:1. The peaks at chemical shifts of δ 4.70 and 4.28 are attributed to the methylene peaks on the end-capping group isocyanide. The peaks at chemical shifts of δ 1.69 and 1.23 are attributed to the hydrogens on the alkyl groups in the alkyl chain segment of the isocyanide.

[0100] The successful preparation of the pyrrole structure was confirmed by analyzing the chemical shifts and integral ratios of the hydrogens on the characteristic structures of pyrrole and benzene rings. And the structure was proved to meet the expectations by the peaks of the methylene groups on the end-capping group isocyanide. The structure obtained by NMR hydrogen spectrum characterization is the ideal target polymer structure, which proves the successful preparation of the polymer.

[0101] Figure 2 This is the NMR carbon spectrum diagram of the hyperbranched pyrrole-based polymer HBPs-3C prepared in Example 1 in deuterated dimethyl sulfoxide; this figure is the NMR carbon spectrum data diagram for the structural characterization of the prepared hyperbranched pyrrole-based photothermal agent. As shown in the figure: By analyzing the carbon spectrum, the peaks at chemical shifts of δ187.53, 171.76, and 160.03 are attributed to the peaks of ketone carbonyl, end-capped isocyanide ester carbonyl, and the carbonyl adjacent to pyrrole in the obtained polymer, respectively. The appearance of the three carbonyl signal peaks with different chemical shifts also confirms the three different carbonyls in the obtained polymer. The peaks at chemical shifts of δ134, 132, 129, 124, and 115 are attributed to the chemical signals on the benzene ring and pyrrole carbon, respectively. The chemical shifts of the carbon signals in the pyrrole and benzene ring structures further illustrate that the polymer we prepared is the ideal target polymer. In addition, the peaks at chemical shifts of δ78.9, 64, and 60 are attributed to the chemical signals of the carbon on the isocyanide. The appearance of the chemical signals on the isocyanide carbon confirms the existence of the end-capping group isocyanide. Therefore, the data of the NMR carbon spectrum prove the successful preparation of the hyperbranched pyrrole-based polymer.

[0102] Figure 3 This is the Fourier transform infrared spectrum diagram comparing the hyperbranched pyrrole-based polymer HBPs-3C prepared in Example 1 with the monomer; this figure is the Fourier transform infrared characterization diagram for the structural characterization of the prepared hyperbranched pyrrole-based photothermal agent. As shown in the figure: By comparing the infrared spectra of the monomer, model compound, and hyperbranched pyrrole-based polymer HBPs-3C, it can be obtained that: The stretching vibration peak at 3400 cm -1 appears in both MC (model compound) and HBPs-3C, which is the peak of the obtained pyrrole N-H. The peak at 2100 cm -1The stretching vibration peak of the monomeric triple-bond alkyne disappeared in MC and HBPs-3C, proving that the alkyne group participated fully in the reaction during the process. Therefore, the peak of the monomeric alkyne group could not be seen in the polymer and the model compound. Located at 2250 cm -1 The stretching vibration peak of the monomeric isocyanide C-N disappeared in MC, and its presence in HBPs-3C proved that the obtained polymer was an ideal isocyanide-capped hyperbranched pyrrolyl polymer, demonstrating the successful preparation of the polymer.

[0103] Figure 4 Figure showing the temperature-time photothermal curve of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 at 365 nm ultraviolet; this figure is the temperature-time photothermal curve of the prepared hyperbranched pyrrolyl photothermal agent at ultraviolet UV - 365 nm. As shown in the figure, by adjusting the irradiation intensity of different UV light powers to irradiate HBPs-3C, the temperature change of the sample was observed. When the irradiation power was 0.1 W / cm 2 and irradiating HBPs-3C, the temperature change was gentle. When the irradiation power was increased to 0.5 W / cm 2 , the temperature change of the sample showed an obvious increasing trend. When the irradiation light source was further increased to 0.8 - 1.0 W / cm 2 , the temperature increased significantly. It rose from room temperature to about 110 degrees within 300 seconds of irradiation. This figure proved that the prepared hyperbranched pyrrolyl polymer had good ultraviolet photothermal conversion performance.

[0104] Figure 5 Figure showing the temperature-time photothermal curve of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1 at 808 nm near-infrared; this figure is the temperature-time photothermal curve of the prepared hyperbranched pyrrolyl photothermal agent at near-infrared 808 nm. As shown in the figure, by adjusting the irradiation intensity of different near-infrared light powers to irradiate HBPs-3C, the temperature change of the sample was obvious. When the irradiation power was 0.6 - 1.5 W / cm 2 and irradiating HBPs-3C, the temperature changed gently from room temperature to around 50 degrees. When the irradiation power was increased to 1.8 W / cm 2 , the temperature change of the sample showed an obvious increasing trend. When the irradiation light source was further increased to 2.0 - 2.5 W / cm 2 , the temperature increased significantly. It rose from room temperature to about 70 degrees within 300 seconds of irradiation. This figure proved that the prepared hyperbranched pyrrolyl polymer had good near-infrared photothermal conversion performance.

[0105] Figure 6UV photothermal stability cycle diagram of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1; this diagram shows the UV photothermal stability test results of the prepared hyperbranched pyrrolyl photothermal agent. By irradiating with a UV light of 0.5 W / cm 2 at 365 nm (UV – 365 nm), the light source was irradiated "on-off" 4 times, and the temperature change of the sample was observed. During the four on-off cycles of light, the temperature change of the sample was stable, and the trend was to rise from room temperature to about 80 °C. After four heating and cooling cycles, the sample stability was good without obvious changes. It is proved that the prepared hyperbranched pyrrolyl photothermal agent has good stability under UV irradiation.

[0106] Figure 7 Near-infrared photothermal stability cycle diagram of the hyperbranched pyrrolyl polymer HBPs-3C prepared in Example 1; this diagram shows the photothermal stability test results of the prepared hyperbranched pyrrolyl photothermal agent. By irradiating with a near-infrared light of 1.8 W / cm 2 at 808 nm (NIR – 808 nm), the light source was irradiated "on-off" 4 times, and the temperature change of the sample was observed. During the four on-off cycles of light, the temperature change of the sample was stable, and the trend was to rise from room temperature to 62 °C. After four heating and cooling cycles, the sample stability was good without obvious changes. It is proved that the prepared hyperbranched pyrrolyl photothermal agent has good stability under near-infrared irradiation.

[0107] Figure 8 UV and near-infrared performance diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 1; this diagram shows the UV, near-infrared photothermal performance and the amount of photothermal agent of the prepared hyperbranched pyrrolyl photothermal agent. In the figure, the purple part is the performance data diagram of the photothermal agent under UV irradiation, and the pink legend is the photothermal data diagram under near-infrared light source irradiation. By comparing the purple and pink legends, it can be seen that the photothermal conversion performance under UV light source irradiation is significantly better than that under near-infrared light source irradiation. The specific analysis is as follows: Taking the UV irradiation data as an example, when the amount of the hyperbranched pyrrolyl photothermal agent is 1.6 wt%, irradiated at a power of 0.5 mW / cm 2 for 50 seconds, the temperature change of the sample is that the temperature rises to 110 °C.

[0108] When irradiated with a near-infrared (pink part data) light source, under the same amount of photothermal agent condition, irradiated at a power of 2.0 W / cm 2 for 300 seconds, the temperature rises to 62 °C. By analyzing the photothermal data of the photothermal agent prepared in this application under different UV and near-infrared light source irradiations, it can be found that the prepared hyperbranched pyrrolyl polymer has the characteristics of dual UV and near-infrared photothermal responses, and its photothermal conversion performance is good, with potential application prospects.

[0109] Figure 9 UV photothermal driving diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 2; The prepared LCE@HBP elastomer thin film spline was placed under irradiation with a UV-365 nm light power intensity of 0.1 W / cm 2 When the light source irradiates the surface of the spline, the temperature rises. When the temperature rises above the liquid crystal isotropic temperature, the liquid crystal units undergo a process of phase transition from anisotropy to isotropy. During the transition process, the ordered arrangement of the liquid crystal units is disrupted, resulting in macroscopic shrinkage deformation. When the light source is removed, the surface temperature of the spline gradually decreases. When it drops below the isotropic temperature, the liquid crystal phase reforms and arranges along the orientation direction, thus showing a process of simulating the opening and closing of a flower.

[0110] Figure 10 Near-infrared photothermal driving diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 2; The prepared LCE@HBP elastomer thin film spline was placed under irradiation with a near-infrared NIR-808 nm light power intensity of 2.0 W / cm 2 When the light source moves to the middle of the spline, the spline in the middle receives the photothermal effect generated by the random illumination, causing unbalanced strain on the elastomer surface. Under the action of this strain, the spline produces a bending deformation with a bending angle of 90 degrees. Subsequently, when the light source is removed, the surface temperature of the spline gradually decreases. When the temperature drops below the isotropic transition temperature, the liquid crystal phase reforms and the liquid crystal units rearrange along the orientation direction again, thus restoring to the shape before heating. Therefore, the spline restores to its shape before deformation.

[0111] Figure 11 Adsorption-desorption curve of the hyperbranched pyrrolyl photothermal agent prepared in Example 1 of this application; The pore structure of the obtained hyperbranched pyrrolyl photothermal agent was verified by nitrogen adsorption separation test. By analyzing the adsorption-desorption curve of the hyperbranched pyrrolyl polymer and the pore size and pore volume distribution, it is obtained that the hyperbranched pyrrolyl photothermal agent indeed generates molecular cavities through the hyperbranched structure, and a large specific surface area is generated through these molecular cavities. Its specific surface area is: 26.55 cm 3 g -1 , the pore size is: 10.41 nm, and the average pore volume is: 0.07 cm 3 g -1 .

[0112] Figure 12 Scanning electron microscope image of the hyperbranched pyrrolyl photothermal agent prepared in Example 1; Scanning electron micrograph of the hyperbranched pyrrolyl photothermal agent obtained in this application under the condition of 100,000-fold magnification. The pores seen on the material surface are the molecular cavities formed due to the hyperbranched structure. As can be seen from the figure, during the formation of the branched structure of the hyperbranched polymer, many molecular cavities with uniform structure and size are formed on the material surface.

[0113] Figure 13 It is a preparation mechanism diagram of the hyperbranched pyrrolyl photothermal agent prepared in Example 1; The figure shows the polymerization reaction mechanism diagram of this application. First, under the condition of a base, the proton on the difunctional isocyanomethylidene is removed to form a highly active 1,3-dipole. Then this dipole coordinates with metallic copper, and after coordination, it reacts with alkynone to obtain a [3+2] cycloaddition reaction product. After that, through aromatization and the dissociation of the carbon-copper bond, the target hyperbranched polymer is finally obtained. (Reference ref: Macromol. Rapid Commun .2024, 2300652) Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A hyperbranched pyrrole-based photothermal agent having ultraviolet and near-infrared dual photothermal effects, characterized in that: The general structural formula of the hyperbranched pyrrole-based photothermal agent is shown in formula (III): (III) Wherein, A is phenyl or triphenylamine, and n=2~8.

2. The hyperbranched pyrrole-based photothermal agent with ultraviolet and near-infrared dual photothermal effects according to claim 1, characterized in that: The weight average molecular weight of the hyperbranched pyrrole-based photothermal agent is 30,000-70,000 (g / mol), and the molecular weight distribution is 1.78-5.

48.

3. A method for preparing a hyperbranched pyrrole-based photothermal agent having ultraviolet and near-infrared dual photothermal effects according to claim 1 or 2, characterized in that: The following steps are involved: The 1,1,1-benzene-1,3,5-benzaldehyde and the acetylation agent are reacted in a first organic solvent at -10 to -5 °C for 1.5 to 3 hours, then the temperature is raised to room temperature, and after stirring for 5 to 10 hours, an oxidizing agent is used for oxidation reaction, and then a trifunctional acetylenic ketone monomer is obtained by separation by column chromatography; The isocyanoacetic acid ester is hydrolyzed and then coupled with a dibromohalogenated hydrocarbon in a second organic solvent to obtain a difunctional isonitrile monomer; A difunctional isonitrile monomer is formed into a 1,3-dipole with the assistance of an inorganic base, and undergoes a cycloaddition polymerization reaction with a trifunctional acetylenic ketone in a third organic solvent under the action of a copper catalyst to obtain a hyperbranched pyrrole-based photothermal agent with ultraviolet and near-infrared dual photothermal effects.

4. The method for preparing a hyperbranched pyrrole-based photothermal agent having ultraviolet and near-infrared dual photothermal effects according to claim 3, characterized in that: The general structural formula of the trifunctional alkynone is shown in formula (I): （I） The general structural formula of the difunctional isonitrile monomer is shown in formula (II): (II) In formula (I) and (II), A is phenyl or triphenylamine; m=3~10.

5. The method for preparing a hyperbranched pyrrole-based photothermal agent having ultraviolet and near-infrared dual photothermal effects according to claim 3, characterized in that: The first organic solvent is tetrahydrofuran and / or diethyl ether; the second organic solvent is one or more of N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone; the third organic solvent is one or more of N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methylpyrrolidone; The oxidant is one or more of 2-iodoxybenzoic acid, manganese dioxide, and chromium trioxide; The copper catalyst is one or more of cuprous iodide, cupric oxide, cuprous bromide, cupric acetate, and cuprous chloride; The inorganic base is one or more of potassium acetate, sodium acetate, potassium carbonate and sodium carbonate.

6. Application of a hyperbranched pyrrole-based photothermal agent with ultraviolet and near-infrared dual photothermal effects in photocontrolled actuators or photothermal conversion.

7. A method for preparing a hyperbranched liquid crystal driver, characterized in that: The following steps are involved: Dissolving a liquid crystal monomer, a chain extender, a cross-linking agent, and thiolactone in N,N-dimethylformamide to obtain a liquid crystal system; A hyperbranched pyrrole-based photothermal agent having ultraviolet and near-infrared dual photothermal effects is mixed with a liquid crystal system at room temperature to obtain a mixed solution; The mixed solution is placed in a mold and reacted at 75-85° C. for 12-48 hours to obtain an elastic film; Among them, the chain extender is dithiol; the cross-linking agent is tetrathiol; and the liquid crystal monomer is the commercial RM82.

8. The method for preparing a hyperbranched liquid crystal driver according to claim 7, characterized in that: Programming of elastomeric films, including: The elastomer film is cross-linked for the second time by using solvent ethylenediamine or cystamine, and the cross-linking gradient difference is constructed on the film surface by using different amounts of chemical cross-linking, and driving forces of different sizes are generated by using the gradient difference.

9. A hyperbranched liquid crystal driver prepared by the method according to claim 7 or 8.

10. Use of the hyperbranched liquid crystal driver according to claim 9 in the field of optical driving.

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