A kind of photonic glass electrically driven elastomer based on high refractive particles and its preparation method

Abstract

The application discloses a kind of photonic glass electrically-driven elastomers based on high-fold particles and preparation method thereof, the photonic glass electrically-driven elastomers includes elastomer film and electrode arranged in elastomer film two sides;The elastomer film uses nanoscale ZnS@SiO2 core-shell particles as optical filler, and the volume ratio of ZnS@SiO2 core-shell particles in elastomer film is 20%~30%.The application introduces ZnS@SiO2 core-shell particles as optical filler, uses the strong light scattering and structural interference enhancement effect brought by ZnS@SiO2 core-shell particles to improve the structural color saturation and color brightness of elastomer material, and optimizes the color performance of elastomer.In addition, the photonic glass electrically-driven elastomers of the application can realize the synergistic regulation of deformation and color change of elastomer material under dielectric effect, and have great application prospect in the fields of optical camouflage, flexible display and intelligent response device.

Description

Technical Field

[0001] This application belongs to the field of structural color materials technology, and specifically relates to a photonic glass electro-driven elastomer based on high-refractive-index particles and its preparation method. Background Technology

[0002] With the rapid development of flexible electronics, smart displays, and biomimetic devices, electrically driven flexible materials capable of reversible deformation under external stimuli have attracted widespread attention. Among them, dielectric elastomers are considered a class of smart actuation materials with significant application prospects due to their advantages such as fast response speed, large actuation strain, simple structure, and light weight. Existing dielectric elastomers typically achieve deformation actuation by applying flexible electrodes to both sides of the elastomer and generating Maxwell stress under the action of an electric field. This has been extensively studied in fields such as soft robotics, flexible actuators, and artificial muscles.

[0003] Meanwhile, structural color elastomers with color-changing capabilities are gradually becoming a research hotspot. Compared with traditional dye or pigment coloring methods, structural color originates from the scattering, interference, and diffraction of light by the micro-nano structures within the material, exhibiting characteristics such as vibrant colors, resistance to fading, and environmental friendliness. Currently, structural color elastomers mostly utilize low-refractive-index colloidal particles such as SiO2 (silicon dioxide), PS (polystyrene), and PMMA (polymethyl methacrylate) to construct photonic structures, achieving color modulation through stretching or compression.

[0004] However, structural color elastomers currently face two major challenges. Firstly, photonic crystals possess long-range ordered periodic structures, resulting in significant color variations with the viewing angle. This strong angle dependence limits their application in wide-viewing-angle displays. Secondly, while long-range disordered and short-range ordered photonic glass materials help reduce angle dependence, their low color saturation and insignificant color-changing effects are problematic. Furthermore, traditional systems composed of low-refractive-index particles, due to their low refractive index contrast, are susceptible to incoherent scattered light, leading to insufficient color saturation, resulting in a whitish color and poor vibrancy, thus affecting the color-changing effect. Simultaneously, these low-dielectric-constant particles struggle to effectively improve the dielectric properties of the elastomer, thereby limiting the material's driving efficiency and response capability under an electric field. Summary of the Invention

[0005] To solve or partially solve the technical problems mentioned in the background art, this application provides a photonic glass electro-driven elastomer based on high-refractive-index particles and its preparation method.

[0006] The first aspect of this application provides a photonic glass electro-driven elastomer based on high-refractive-index particles, which includes an elastomer film and electrodes disposed on both sides of the elastomer film; the elastomer film uses nanoscale ZnS@SiO2 core-shell particles as optical fillers, and the volume percentage of ZnS@SiO2 core-shell particles in the elastomer film is 20%~30%.

[0007] In some embodiments, the core-shell diameter of the ZnS@SiO2 core-shell particles is 120 nm to 290 nm, and more specifically 130 nm to 250 nm.

[0008] In some embodiments, the core radius of the ZnS@SiO2 core-shell particles is 48~80nm, and the shell thickness is 20~58nm.

[0009] In some embodiments, the matrix material of the elastomer film is polyacrylate.

[0010] In some embodiments, the electrode is a carbon ester electrode, a carbon nanotube electrode, or a silver nanowire electrode.

[0011] The method for preparing the above-mentioned photonic glass electro-driven elastomer provided in the second aspect of this application includes: Nanoscale ZnS@SiO2 core-shell particles and photofunctional additives are dispersed in acrylate monomers and then cured to prepare an elastomer film; the photofunctional additives include at least a photoinitiator. Electrodes are imprinted on both sides of the elastomer film.

[0012] In the preparation method of this application, in order to disperse the nano-sized ZnS@SiO2 core-shell particles and photofunctional additives in the acrylate monomer, the acrylate monomer that is liquid at room temperature should be selected.

[0013] In some embodiments, the amount of photoinitiator used is 0.1% to 3% of the mass of the acrylate monomer.

[0014] In some embodiments, the photofunctional additive further includes a light absorber, wherein the amount of the light absorber is 0.1% to 3% of the mass of the acrylate monomer.

[0015] In some embodiments, the acrylate monomer is one or more of ethylene glycol phenyl acrylate, diethylene glycol ethyl ether acrylate, hexanediol diacrylate, 2-hydroxy-3-phenoxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, and polyethylene glycol dimethacrylate.

[0016] In some embodiments, the photoinitiator is 2-hydroxy-2-methylphenylacetone.

[0017] In some embodiments, the light absorber is one or more of natural melanin, carbon black, carbon nanotubes, graphene, and polydopamine.

[0018] Natural melanin can be prepared using the following methods: Fresh ink was extracted from the ink sac of the golden cuttlefish and dispersed in deionized water to obtain an initial dispersion. The initial dispersion was centrifuged at low speed to precipitate the tissue residues and large aggregates in the ink, and the supernatant was collected. The supernatant was centrifuged at high speed to precipitate melanin particles, and the precipitate was collected. The precipitate was redispersed in deionized water and washed by centrifugation to remove residual water-soluble impurities; The precipitate after centrifugation and washing was dispersed in anhydrous ethanol, and further lipid-soluble impurities were removed by solvent replacement. Repeat steps (4) to (5) at least three times, and the final precipitate is dried to obtain nano-sized natural melanin.

[0019] The above-mentioned method involves dispersing nano-sized ZnS@SiO2 core-shell particles and photofunctional additives in acrylate monomers, followed by curing to prepare an elastomer film. Specifically: First, nano-sized ZnS@SiO2 core-shell particles, photofunctional additives, and acrylate monomers are mixed and dispersed in an organic solvent using an organic solvent dispersion method. Then, the organic solvent is removed by evaporation to obtain a dispersion. The dispersion is injected into a cavity formed between two glass slides, and the resulting film, i.e., an elastomer film, is cured.

[0020] The organic solvent selected in this application should have an evaporation temperature not higher than the boiling point of the acrylate monomer; and the organic solvent should also be miscible with the acrylate monomer. Therefore, the organic solvent may include methanol, ethanol, isopropanol, ethyl acetate, etc.

[0021] Compared with the prior art, this application has the following advantages and beneficial effects: This application introduces high-refractive-index particles (ZnS@SiO2 core-shell particles) as optical fillers. By utilizing the strong light scattering and structural interference enhancement effects brought by high-refractive-index particles, the structural color saturation and color brightness of the elastomer material are improved, thereby optimizing the color performance of the elastomer. Compared to spherical optical fillers such as SiO2, PS, and PMMA commonly used in traditional photonic materials, ZnS, with its higher dielectric constant, can improve the deformation efficiency of elastomers under an electric field.

[0022] The photonic glass electro-driven elastomer of this application can achieve coordinated control of deformation and color change of elastomer materials under dielectric action, and has great application prospects in the fields of optical camouflage, flexible display and intelligent response device.

[0023] The preparation process of this application is simple and easy to control.

[0024] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0025] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.

[0026] Figure 1 A schematic diagram of the structure of the photonic glass electro-driven elastomer in this application is shown. Figure (a) is a schematic diagram of the explosion decomposition, and Figure (b) is a schematic diagram of the usage state, wherein 1-CNT electrode, 2-elastomer film.

[0027] Figure 2 The theoretical model of the core-shell structure dimensions and the fitting curve are shown.

[0028] Figure 3 The refractive index of the thin film sample in Example 2 is shown.

[0029] Figure 4 The reflectance spectrum of the thin film sample in Example 3 is shown.

[0030] Figure 5 The reflectance spectrum of the thin film sample in Example 4 is shown.

[0031] Figure 6 The reflectance spectra of the thin film samples in Example 5 are shown. Figure (a) shows the reflectance spectra of the elastomer thin film sample with a ZnS@SiO2 core-shell particle volume fraction of 25%. Figure 6 (b) is the reflectance spectrum of an elastomer film sample with a ZnS@SiO2 core-shell particle volume fraction of 20%; Figure 6 (c) Color blocks are shown for different elastomer film samples.

[0032] Figure 7 The reflectance spectrum curves of the thin film sample in Example 6 under different elongation strains are shown.

[0033] Figure 8 The colors of the electrically driven elastomer in Example 7 at different voltages are shown. Detailed Implementation

[0034] To further illustrate this application, a detailed description is provided below with reference to embodiments. However, it should be understood that these descriptions are merely for further illustrating the features and advantages of this application, and not for limiting the scope of the claims of this application. Example

[0035] In this embodiment, ZnS@SiO2 core-shell particles were prepared using the sol-gel method. The preparation steps are as follows: In a 250 mL flask, 0.8 g of ZnS nanoparticles were dispersed in 160 mL of ethanol; The dispersion of ZnS nanoparticles was mixed with 6 mL of ammonia water (analytical grade, mass concentration 25%~28%, manufacturer: Chengdu Kelong Chemical) and 12 mL of deionized water, and stirred in an oil bath at 25℃ for 1 hour. Add tetraethyl orthosilicate (TEOS, analytical grade, manufacturer: Chengdu Kelong Chemical), and stir the reaction in a constant temperature water bath at 25℃ for 5 hours; The reaction solution was centrifuged at 7000 rpm for 10 minutes, washed with deionized water and anhydrous ethanol, and the resulting product was dried in a forced-air drying oven at 60°C for 12 hours to obtain nano-sized ZnS@SiO2 core-shell particles.

[0036] In this embodiment, by varying the particle size of ZnS nanoparticles and the amount of TEOS, ZnS@SiO2 core-shell particles with different core-shell structure sizes were obtained, and the average particle size and core layer thickness of the ZnS@SiO2 core-shell particles were measured. The amount of TEOS used ranged from 1.5 to 14 mL.

[0037] Please see Figure 2 The figure shows the theoretical model and fitting curves for the core-shell structure dimensions. The blue curve represents the theoretical model, corresponding to the formula y = 0.1345x; the red curve represents the fitting curve, corresponding to the fitting formula y = 0.1407x - 0.8939, with a goodness of fit R0.1345. 2 =0.931.

[0038] from Figure 2 It can be seen that the volume ratio of the shell to the core is... and Proportional. Using the vertical axis as the ordinate, with Plotting the measured values ​​in this embodiment on the x-axis, it was found that the relative error between the theoretical value predicted by the theoretical model and the measured value is small. Therefore, the theoretical model can be used to predict the average particle size of ZnS@SiO2 core-shell particles.

[0039] Based on the theoretical model, the following prediction formula is obtained: (1) in, Indicates the particle size of the core-shell particles; The value represents the core layer diameter, taken as the average particle size of ZnS nanoparticles. Indicates the volumetric amount of TEOS used; This indicates the volumetric amount of ZnS nanoparticles used, which is based on the mass and theoretical density of the ZnS nanoparticles (4.09 g / cm³). 3 ) was calculated.

[0040] Therefore, given the average particle size of ZnS nanoparticles and the amounts of TEOS and ZnS nanoparticles, the predicted particle size of ZnS@SiO2 core-shell particles can be obtained.

[0041] Example 2 In this embodiment, ZnS@SiO2 core-shell particles were used as high-refractive-index particles to prepare elastomer film samples, and the refractive indices of different core-shell particles were obtained by measurement and calculation. The specific steps are as follows: (1) Preparation of ZnS@SiO2 core-shell particle samples C d80 S d20 C d78 S d45 C d48 S d40 : Sample C d80 S d20 The preparation method is as follows: First, in a 250 mL flask, 0.8 g of ZnS nanoparticles with an average particle size of 160 nm were dispersed in 160 mL of ethanol. Then, the dispersion of ZnS nanoparticles was mixed with 6 mL of ammonia water (analytical grade, mass concentration 25%~28%, manufacturer: Chengdu Kelong Chemical) and 12 mL of deionized water, and stirred in an oil bath at 25℃ for 1 hour. Next, add 1.6 mL of tetraethyl orthosilicate (TEOS, analytical grade, manufacturer: Chengdu Kelong Chemical), and stir the mixture in a constant temperature water bath at 25°C for 5 hours. Finally, the reaction solution was centrifuged at 7000 rpm for 10 minutes, washed with deionized water and anhydrous ethanol, and the resulting product was dried in a forced-air drying oven at 60°C for 12 hours to obtain nanoscale ZnS@SiO2 core-shell particle sample C. d80 S d20 .

[0042] Compared to sample C d80 S d20 Preparation method of sample C d78 S d45 The only difference in the preparation methods is that the average particle size of the ZnS nanoparticles used is 156 nm, and the amount of TEOS used is 4 mL.

[0043] Compared to sample C d80 S d20 Preparation method of sample C d48 S d40The only difference in the preparation methods is that the average particle size of the ZnS nanoparticles used is 96 nm, and the amount of TEOS used is 8 mL.

[0044] In this application, the prepared ZnS@SiO2 core-shell particle sample is expressed as C. dx S dy , where dx represents the radius of the ZnS core layer and dy represents the thickness of the SiO2 shell layer.

[0045] Sample C was used respectively d80 S d20 C d78 S d45 C d48 S d40 Preparation of elastomer film samples: Prepare samples C separately in advance d80 S d20 C d78 S d45 C d48 S d40 An ethanol solution (10%, w / w) with a mass concentration of 10% is prepared for use.

[0046] Using sample C d80 S d20 The method for preparing the elastomer film sample is as follows: 14.56g of sample C d80 S d20 An ethanol solution was mixed with 0.015 g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical), 0.711 g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical), and 0.789 g of PEGPEA (analytical grade, Sigma-Aldrich) and sonicated for 10 minutes. The mixture was then placed in an oven at 70°C for 4 hours to evaporate the ethanol, yielding a dispersion. The dispersion was used to prepare an elastomer film sample.

[0047] Using sample C d78 S d45 The only difference between the methods for preparing elastomer film samples is that: Sample C d78 S d45 The amount of ethanol solution used was 12.23 g.

[0048] Using sample C d48 S d40 The only difference between the methods for preparing elastomer film samples is that: Sample C d48 S d40 The amount of ethanol solution used was 11.29 g.

[0049] The specific method for preparing the dispersion into an elastomer film sample is as follows: Place two clean glass slides in deionized water, ultrasonically wash for 5 minutes, dry, and then treat with an 80 W plasma cleaner for 2 minutes. Place the glass slides on a spin coater with the treated side facing up, and add a polyvinyl alcohol aqueous solution (concentration: 4%, w / w; type 1788 PVA, degree of alcoholysis 87%~89% mol / mol). Spin coat at 3000 rpm for 40 seconds to form a PVA film on the glass slide as a sacrificial layer to facilitate the subsequent peeling and curing of the elastomer.

[0050] 120 μL of the dispersion was injected between two glass slides with a 100 μm thick polytetrafluoroethylene (PTFE) liner. The slides were then placed in a 60°C oven for 1 minute to allow for uniform dispersion. Afterwards, the dispersion was exposed to ultraviolet light (power: 85 W, wavelength: 365 nm, power density: 24 mW / cm²). 2 Curing is performed on both sides for 40 seconds each, followed by peeling off the elastomer.

[0051] Meanwhile, acrylate-based thin film samples were also prepared. The preparation method was as follows: 0.015g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical), 0.711g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical), and 0.789g of PEGPEA (analytical grade, Sigma-Aldrich) were mixed and sonicated for 10 minutes; the resulting mixture was then used to prepare an elastomer thin film sample.

[0052] The refractive index data of the acrylate matrix film sample and the elastomer film sample prepared in this embodiment were measured using a prism refractometer, and the Cauchy dispersion model was used for fitting to obtain... Figure 3 The curve showing the refractive index as a function of incident wavelength is presented. Figure 3 It can be seen that the fitting curve based on the Cauchy dispersion model passes well through the measurement point, and the refractive indices of each thin film sample at an incident wavelength of 589 nm are 1.555, 1.532, 1.510, and 1.500, respectively.

[0053] By substituting the refractive index of the acrylate matrix film and each elastomer film sample, as well as the volume fraction of ZnS@SiO2 core-shell particles in the matrix, into the Bruggeman formula, the refractive index data of different ZnS@SiO2 core-shell particle samples were obtained, as shown in Table 1. In this embodiment, four elastomer film samples were prepared, all with a ZnS@SiO2 core-shell particle volume fraction of 25%.

[0054] Table 1 Physical parameters of ZnS@SiO2 core-shell particles

[0055] Table 1 Physical parameters of ZnS@SiO2 core-shell particles As shown in Table 1, the refractive index of the core-shell particles increases with the increase of ZnS volume fraction from 16.2% to 51.2%; at an incident wavelength of 589 nm, the refractive index of the core-shell particles increases from 1.54 to 1.72. The data in Table 1 indicate that high-refractive-index particles were synthesized, and the refractive index can be controlled by adjusting the ZnS volume fraction in the ZnS@SiO2 core-shell particles.

[0056] Example 3 In this embodiment, ZnS@SiO2 core-shell particles were used as high-refractive-index particles to prepare elastomer thin film samples, and the effect of the volume fraction of ZnS@SiO2 core-shell particles on the optical properties of the elastomer was analyzed. The specific steps are as follows: (1) Preparation of ZnS@SiO2 core-shell particle samples C d48 S d58 : First, in a 250 mL flask, 0.8 g of ZnS nanoparticles with an average particle size of 96 nm were dispersed in 160 mL of ethanol. Then, the dispersion of ZnS nanoparticles was mixed with 6 mL of ammonia water (analytical grade, mass concentration 25%~28%, manufacturer: Chengdu Kelong Chemical) and 12 mL of deionized water, and stirred in an oil bath at 25℃ for 1 hour. Next, add 14 mL of tetraethyl orthosilicate (TEOS, analytical grade, manufacturer: Chengdu Kelong Chemical), and stir the mixture in a constant temperature water bath at 25°C for 5 hours. Finally, the reaction solution was centrifuged at 7000 rpm for 10 minutes, washed with deionized water and anhydrous ethanol, and the resulting product was dried in a forced-air drying oven at 60°C for 12 hours to obtain nanoscale ZnS@SiO2 core-shell particle sample C. d48 S d58 .

[0057] (2) Using sample C d48 S d58 Preparation of elastomer film samples: Pre-prepared sample C d48 S d58 Prepare an ethanol solution (10%, w / w) for later use.

[0058] Samples C were taken in the amounts of 13.93g, 10.83g, and 8.12g respectively. d48 S d58 An ethanol solution was used to prepare sample C. d48 S d58The ethanol solution and 0.0045g of melanin particles were mixed and sonicated for 1 hour; 0.015g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical) and 1.5g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical) were added, and sonication was continued for 10 minutes; the mixture was placed in an oven at 70℃ for 4 hours to evaporate the ethanol and obtain a dispersion.

[0059] The dispersion was prepared into an elastomer film sample with a thickness of 50 μm using the method described in Example 2. Three groups of elastomer film samples were obtained, in which the volume fractions of ZnS@SiO2 core-shell particles were 30%, 25%, and 20%, respectively.

[0060] The reflectance data of each elastomer film sample were measured at incident wavelengths from 400 nm to 800 nm, as shown in the figure. Figure 4 As shown. From Figure 4 It can be seen that the higher the volume fraction of ZnS@SiO2 core-shell particles, the more ZnS@SiO2 core-shell particles there are per unit volume of the elastomer film, and the stronger the multiple scattering effect. Therefore, the reflectivity of the elastomer film sample in the high-reflection band of 500nm~650nm shows an increasing trend.

[0061] Furthermore, as the volume fraction of ZnS@SiO2 core-shell particles increases, the particles become more densely packed, and the spacing decreases, corresponding to a shortening of the structural period in the Bragg equation, resulting in a blue shift in the photonic bandgap of the elastomeric film sample. The denser particle packing also increases the degree of order in the particle accumulation, leading to increased coherence of the scattered light and making the structural peaks more pronounced. Therefore, the reflectivity and reflection peak position of the elastomeric film sample can be adjusted by controlling the volume fraction of ZnS@SiO2 core-shell particles.

[0062] Example 4 In this embodiment, ZnS@SiO2 core-shell particles were used as high-refractive-index particles to prepare elastomer thin film samples, and the effect of the shell thickness of ZnS@SiO2 core-shell particles on the optical properties of the elastomer was analyzed. The specific steps are as follows: (1) Preparation of ZnS@SiO2 core-shell particle samples C d48 S d20 C d48 S d24 C d48 S d34 : Sample C d48 S d20 The preparation method is as follows: First, in a 250 mL flask, 0.8 g of ZnS nanoparticles with an average particle size of 96 nm were dispersed in 160 mL of ethanol. Then, the dispersion of ZnS nanoparticles was mixed with 6 mL of ammonia water (analytical grade, mass concentration 25%~28%, manufacturer: Chengdu Kelong Chemical) and 12 mL of deionized water, and stirred in an oil bath at 25℃ for 1 hour. Next, add 4 mL of tetraethyl orthosilicate (TEOS, analytical grade, manufacturer: Chengdu Kelong Chemical), and stir the mixture in a constant temperature water bath at 25°C for 5 hours. Finally, the reaction solution was centrifuged at 7000 rpm for 10 minutes, washed with deionized water and anhydrous ethanol, and the resulting product was dried in a forced-air drying oven at 60°C for 12 hours to obtain nanoscale ZnS@SiO2 core-shell particle sample C. d48 S d20 .

[0063] Compared to sample C d48 S d20 Preparation method of sample C d48 S d24 The only difference in the preparation method is that the amount of TEOS used is 6 mL.

[0064] Compared to sample C d48 S d20 Preparation method of sample C d48 S d34 The only difference in the preparation method is that the amount of TEOS used is 8 mL.

[0065] (2) Sample C was used respectively d48 S d20 C d48 S d24 C d48 S d34 Preparation of elastomer film samples: Prepare samples C separately in advance d48 S d20 C d48 S d24 C d48 S d34 Prepare an ethanol solution (10%, w / w) for later use.

[0066] Using sample C d48 S d20 The method for preparing the elastomer film sample is as follows: 13.48g of sample C d48 S d20An ethanol solution and 0.0045 g of melanin particles were mixed and sonicated for 1 hour. Then, 0.015 g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical) and 1.5 g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical) were added, and sonication continued for 10 minutes. The mixture was then placed in an oven at 70°C for 4 hours to evaporate the ethanol, yielding a dispersion. The dispersion was used to prepare an elastomer film sample.

[0067] Using sample C d48 S d24 The only difference between the methods for preparing elastomer film samples is that: Sample C d48 S d24 The amount of ethanol solution used was 12.89 g.

[0068] Using sample C d48 S d34 The only difference between the methods for preparing elastomer film samples is that: Sample C d48 S d34 The amount of ethanol solution used was 11.96 g.

[0069] The three sets of elastomer film samples prepared all had a thickness of 50 μm, and the volume fraction of ZnS@SiO2 core-shell particles was 25% in each sample.

[0070] The reflectance of each elastomer film sample was tested at different incident wavelengths, see below. Figure 5 As shown. Figure 5 The color patches corresponding to each elastomer film sample were obtained by photographing the samples with a Sony Alpha 7Ⅲ camera. The samples were placed in a photography box with a black light-absorbing velvet cloth as the background, and a ring light source was used to illuminate from above. The shooting parameters were set as follows: ISO 1200, aperture f / 16, and shutter speed 1 / 80s.

[0071] from Figure 5 It is known that when the thickness of the elastomer film sample and the volume fraction of high-refractive-index particles remain constant, increasing the shell thickness of the high-refractive-index particles causes a redshift in the high-reflectance band of the elastomer film sample, and the color gradually changes from blue to green. This is because when the particle size increases while the volume fraction remains constant, the interparticle spacing increases accordingly, leading to a redshift in the central reflection band. Therefore, the color of the elastomer can be adjusted by controlling the particle shell thickness.

[0072] Example 5 This embodiment uses sample C from Example 4. d48 S d34 The following steps were taken to prepare elastomer thin film samples as high-refractive-index particles and to analyze the effect of the elastomer thin film sample thickness on the optical properties of the elastomer: First, prepare sample C in advance. d48 S d34 Prepare an ethanol solution (10%, w / w) for later use.

[0073] Then, sample C was used. d48 S d34 Preparation of elastomer film samples: 11.96 g and 8.97 g of sample C were taken respectively. d48 S d34 An ethanol solution was used to prepare sample C. d48 S d34 An ethanol solution and 0.0045 g of melanin particles were mixed and sonicated for 1 hour. Then, 0.015 g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical) and 1.5 g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical) were added, and sonication continued for 10 minutes. The mixture was then placed in an oven at 70°C for 4 hours to evaporate the ethanol, yielding a dispersion. Elastomer film samples with thicknesses of 50 μm and 100 μm were prepared from both dispersions using the method described in Example 2.

[0074] Using 11.96g sample C d48 S d34 In the elastomer film sample prepared with ethanol solution, the volume fraction of ZnS@SiO2 core-shell particles was 25%; when using 8.97g sample C d48 S d34 In the elastomer film sample prepared by the ethanol solution, the volume fraction of ZnS@SiO2 core-shell particles was 20%.

[0075] The prepared elastomer film samples were characterized by reflectance spectroscopy. The reflectance spectral data are shown in [reference needed]. Figure 6 ,in, Figure 6 (a) is the reflectance spectrum of an elastomer film sample with a ZnS@SiO2 core-shell particle volume fraction of 25%. Figure 6 (b) is the reflectance spectrum of an elastomer film sample with a ZnS@SiO2 core-shell particle volume fraction of 20%; Figure 6 (c) Color blocks are shown for different elastomer film samples.

[0076] Figure 6 (c) The color patches corresponding to each elastomer film sample are obtained from the samples taken with a Sony Alpha 7Ⅲ camera. The samples were placed in a photography box with a black light-absorbing velvet cloth as the background, and a ring light source was used to illuminate from the top. The shooting parameters were set as follows: ISO 1200, aperture f / 16, and shutter speed 1 / 80s.

[0077] from Figure 6It is known that, at the same volume fraction, the 50 μm thick elastomer exhibits a distinct reflection peak, with a higher peak reflectance than the 100 μm thick elastomer. Optical photographs also show that the thinner sample generally displays a more pronounced structural color. Although theoretically, thicker samples should reflect light more strongly, in the elastomers of this application, increased thickness is often accompanied by more interface defects and internal scattering. Furthermore, during photocuring, thicker samples experience more significant shrinkage, accumulating more shrinkage stress, leading to more incoherent scattering or absorption of light during propagation, thereby reducing the reflectance at the center wavelength.

[0078] Example 6 This embodiment uses sample C from Example 4. d48 S d34 The following steps were taken to prepare elastomer film samples as high-refractive-index particles and to analyze the optical properties of the elastomer film samples under tension: First, prepare sample C in advance. d48 S d34 Prepare an ethanol solution (10%, w / w) for later use.

[0079] Then, sample C was used. d48 S d34 Preparation of elastomer film samples: Take 8.97g of sample C d48 S d34 An ethanol solution was used to prepare sample C. d48 S d34 An ethanol solution and 0.0045 g of melanin particles were mixed and sonicated for 1 hour. 0.015 g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical) and 1.5 g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical) were added, and sonication continued for 10 minutes. The mixture was then placed in an oven at 70°C for 4 hours to evaporate the ethanol, yielding a dispersion. The dispersion was used to prepare an elastomer film sample with a thickness of 50 μm and a length of 2 cm using the method described in Example 2. The volume fraction of ZnS@SiO2 core-shell particles in this elastomer film sample was 20%.

[0080] The elastomer film sample was fixed on a stretching die and stretched. The reflectance spectra of the stretched elastomer film sample were then characterized. The reflectance spectra data are shown below. Figure 7 .from Figure 7It can be seen that, in the unstretched state, the elastomer film sample exhibits a broad reflection peak at an incident wavelength of approximately 430 nm, and the sample appears blue. As the tensile strain increases from 0% to 105%, the reflectivity significantly increases, reaching its maximum at a tensile strain of 60%, and the peak width gradually narrows, resulting in a significant increase in the brightness and saturation of the sample color. Furthermore, due to the decrease in interparticle spacing along the thickness direction, the reflection peak undergoes a blue shift, and the color gradually transitions from blue to purple, achieving controllable color adjustment. However, after the tensile strain exceeds 60%, the center wavelength of the reflection peak transitions to the ultraviolet region, and the sample color gradually lightens. Upon release of the tension, the sample quickly returns to its initial length and color.

[0081] The reflectance spectra of the elastomer film samples in Examples 3-6 were tested using the following method: Reflectance spectroscopy measurements were performed using a three-port integrating sphere (Fuxiang Optics IS-20-5-R) paired with a deuterium halogen lamp light source (Fuxiang Optics iDH2000-BSC) and a spectrometer (Fuxiang Optics PG2000-PRO-EX). The spectrometer's test wavelength range was 175 nm to 1112 nm, and the slit width was 25 μm. The elastomer film sample was placed between the three-port integrating sphere and the deuterium halogen lamp light source, with the incident light incident at an angle of 8° to the vertical direction. The reflected light entered the three-port integrating sphere and was collected by the spectrometer. The spectrometer collected wavelengths ranging from 400 nm to 800 nm, and a standard PTFE diffuse reflection white plate with 100% reflectivity was used as the reference.

[0082] Example 7 In this embodiment, ZnS@SiO2 core-shell particles were used as high-refractive-index particles to prepare elastomer film samples, and an electro-driven experiment was conducted on the elastomer film samples. The specific steps are as follows: (1) Preparation of ZnS@SiO2 core-shell particle samples C d48 S d42 : Sample C d48 S d42 The preparation method is as follows: First, in a 250 mL flask, 0.8 g of ZnS nanoparticles with an average particle size of 96 nm were dispersed in 160 mL of ethanol. Then, the dispersion of ZnS nanoparticles was mixed with 6 mL of ammonia water (analytical grade, mass concentration 25%~28%, manufacturer: Chengdu Kelong Chemical) and 12 mL of deionized water, and stirred in an oil bath at 25℃ for 1 hour. Next, add 8 mL of tetraethyl orthosilicate (TEOS, analytical grade, manufacturer: Chengdu Kelong Chemical), and stir the mixture in a constant temperature water bath at 25°C for 5 hours. Finally, the reaction solution was centrifuged at 7000 rpm for 10 minutes, washed with deionized water and anhydrous ethanol, and the resulting product was dried in a forced-air drying oven at 60°C for 12 hours to obtain nanoscale ZnS@SiO2 core-shell particle sample C. d48 S d42 .

[0083] Although the preparation process of the ZnS@SiO2 core-shell particle sample in this embodiment is different from that of sample C in Example 2 d48 S d40 The preparation processes are the same, but due to different batches, the size of the resulting samples varies.

[0084] (2) Using sample C d48 S d42 Preparation of elastomer film samples: Pre-prepared sample C d48 S d42 Prepare an ethanol solution (10%, w / w) for later use.

[0085] 8.97g of sample C d48 S d42 An ethanol solution and 0.0045 g of melanin particles were mixed and sonicated for 1 hour. Then, 0.015 g of 2-hydroxy-2-methylphenylacetone (model: Darocur 1173, analytical grade, manufacturer: Shanghai Aladdin Biochemical) and 1.5 g of DEGEEA (chromatographic grade, manufacturer: Shanghai Aladdin Biochemical) were added, and sonication continued for 10 minutes. The mixture was then placed in an oven at 70°C for 4 hours to evaporate the ethanol, yielding a dispersion. The dispersion was used to prepare an elastomer film sample.

[0086] An elastomer film sample is fixed on an acrylic plate, and a carbon nanotube film is transferred to both sides of the elastomer film sample to obtain an electrically driven elastomer. In this embodiment, the electrically driven elastomer consists of an elastomer film 2 and CNT electrodes 1 disposed on both sides of the elastomer film 2, see [link to documentation]. Figure 1 As shown, the resulting electrically driven elastomer can deform and change color under dielectric action.

[0087] Specifically, 50 mg of carboxyl-purified carbon nanotubes (CNTs) with an inner diameter of 0.8–1.6 nm, an outer diameter of 1–2 nm, and a length of 5–30 μm were dispersed in 200 g of deionized water containing 0.5% w / w sodium dodecyl sulfate. The mixture was ultrasonically dispersed, and aggregates were removed by centrifugation to obtain a CNT dispersion with a concentration of 0.0145% w / w. 2 ml of the CNT dispersion was diluted to 4 ml with isopropanol and filtered through a PVDF membrane with a pore size of 0.22 μm and a diameter of 90 mm to form a thin CNT membrane. Subsequently, the elastomer film sample was fixed on an acrylic plate, and the transparent CNT membrane was transferred to both sides of the elastomer film sample.

[0088] An electro-drive experiment was conducted on the electro-driven elastomer using a TCM6000i high-voltage power supply. As the applied voltage increased, the electro-driven elastomer gradually underwent indentation deformation, accompanied by a color change. See... Figure 8 As shown, as the voltage increases from 0V to 770V, the electrically driven elastomer gradually changes from blue to purple. When the voltage is further increased to 950V, the color begins to appear grayish, because the elastomer's color change range extends beyond visible light, and the color of the carbon nanotube electrode begins to show.

[0089] Furthermore, in Examples 3-7, the melanin particles were prepared using the following method: Take 30g of fresh ink from the ink sac of the golden cuttlefish (Sepia esculenta), add it to 200mL of deionized water, and disperse the ink by magnetic stirring to obtain a preliminary dispersion. The initial dispersion was centrifuged at 3000 rpm for 10 minutes, and the precipitate was discarded to remove tissue residues and large aggregates in the ink. The supernatant containing melanin particles was collected. Centrifuge the supernatant at 11,000 rpm for 20 minutes to allow melanin particles to precipitate fully, and discard the supernatant. The precipitate was redispersed in deionized water and washed again by centrifugation to remove residual water-soluble impurities. The precipitate was dispersed in anhydrous ethanol, and the lipid-soluble impurities were further removed by solvent displacement.

[0090] Repeat steps (4) to (5) at least three times to ensure the purity of the melanin particles. The final precipitate is dried to obtain nano-sized melanin particles.

[0091] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A photonic glass electro-driven elastomer based on high-refractive-index particles, characterized in that: It includes an elastomer film and electrodes disposed on both sides of the elastomer film; The elastomeric film uses nanoscale ZnS@SiO2 core-shell particles as optical fillers, and the volume percentage of ZnS@SiO2 core-shell particles in the elastomeric film is 20%~30%.

2. The photonic glass electro-driven elastomer as described in claim 1, characterized in that: The core-shell diameter of the ZnS@SiO2 core-shell particles is 120nm~290nm.

3. The photonic glass electro-driven elastomer as described in claim 1, characterized in that: The core-shell particles of the ZnS@SiO2 have a core radius of 48-80 nm and a shell thickness of 20-58 nm.

4. The photonic glass electro-driven elastomer as described in claim 1, characterized in that: The matrix material of the elastomer film is a polyacrylate material.

5. The photonic glass electro-driven elastomer as described in claim 1, characterized in that: The electrode is a carbon ester electrode, a carbon nanotube electrode, or a silver nanowire electrode.

6. The method for preparing the photonic glass electro-driven elastomer according to claim 1, characterized in that, include: Nanoscale ZnS@SiO2 core-shell particles and photofunctional additives are dispersed in acrylate monomers and then cured to prepare an elastomer film; the photofunctional additives include at least a photoinitiator. Electrodes are imprinted on both sides of the elastomer film.

7. The preparation method according to claim 6, characterized in that: The acrylate monomer is one or more of the following: ethylene glycol phenyl acrylate, diethylene glycol ethyl ether acrylate, hexanediol diacrylate, 2-hydroxy-3-phenoxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, and polyethylene glycol dimethacrylate.

8. The preparation method according to claim 6, characterized in that: The photoinitiator is 2-hydroxy-2-methylphenylacetone.

9. The preparation method according to claim 6, characterized in that: The light absorber is one or more of the following: natural melanin, carbon black, carbon nanotubes, graphene, and polydopamine.

10. The preparation method according to claim 6, characterized in that: The process of dispersing nano-sized ZnS@SiO2 core-shell particles and photofunctional additives in acrylate monomers and then curing them to prepare an elastomer film is as follows: First, nano-sized ZnS@SiO2 core-shell particles, photofunctional additives, and acrylate monomers are mixed and dispersed in an organic solvent using an organic solvent dispersion method. Then, the organic solvent is removed by evaporation to obtain a dispersion. The dispersion is injected into a cavity formed between two glass slides, and the resulting film, i.e., an elastomer film, is cured.

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