Near-infrared mechanical light-emitting film based on stress excitation as well as preparation method and application of near-infrared mechanical light-emitting film

Abstract

The invention discloses a near-infrared mechanical light-emitting film based on stress excitation and a preparation method and application thereof, and solves the problems that an existing photoelectric material depends on external light source excitation, energy consumption is high, penetrability in biomedical imaging is limited, or the existing photoelectric material has an efficient light-emitting characteristic, and the cost is low. However, the external quantum efficiency of the organic light-emitting diode is still lower than that of a visible light organic light-emitting diode, and the biological compatibility needs to be improved. The polymer capable of generating deformation is obtained by blending the near-infrared stress luminescent powder and the polymer with high elasticity. The elastic film capable of generating near-infrared luminescence is prepared through a layer-by-layer preparation method, and luminescence is caused by the performance of a near-infrared mechanoluminescence material in a near-infrared luminescence layer; the preparation method is simple.

Description

Technical Field

[0001] The present invention relates to the field of preparation of functional materials, and particularly to a near-infrared mechanoluminescent thin film based on stress excitation, a preparation method thereof, and an application thereof. Background Art

[0002] Traditional optoelectronic materials such as photoluminescent materials (such as fluorescent materials) and electroluminescent materials (such as OLEDs) have some limitations in applications. Photoluminescent materials rely on external light sources for excitation, consume high energy and have limited penetration in biomedical imaging; while electroluminescent materials (such as NIR OLEDs), although having high-efficiency luminescence characteristics, their external quantum efficiency is still lower than that of visible-light organic light-emitting diodes, and there is room for improvement in terms of biocompatibility. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems existing in the existing optoelectronic materials, that is, they rely on external light sources for excitation, consume high energy and have limited penetration in biomedical imaging, or have high-efficiency luminescence characteristics, but their external quantum efficiency is still lower than that of visible-light organic light-emitting diodes, and there is room for improvement in terms of biocompatibility. Therefore, a near-infrared mechanoluminescent thin film based on stress excitation, a preparation method thereof, and an application thereof are provided.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] A near-infrared mechanoluminescent thin film based on stress excitation, which is characterized in that: it includes a first flexible base layer, a near-infrared light-emitting layer and a second flexible base layer that are sequentially covered on the first flexible base layer from bottom to top;

[0006] The raw materials of the first flexible base layer and the second flexible base layer are a dielectric elastomer A, the thickness of the first flexible base layer is 100 - 1000 μm, and the thickness of the second flexible base layer is 100 - 500 μm;

[0007] The raw materials of the near-infrared light-emitting layer are a dielectric elastomer B and a near-infrared force-induced luminescence powder, and the mass ratio of the dielectric elastomer B to the near-infrared force-induced luminescence powder is 1:0.2 - 4; the thickness of the near-infrared light-emitting layer is 0.98 mm - 1.1 mm;

[0008] The mass ratio of the dielectric elastomer A of the first flexible base layer and the second flexible base layer to the dielectric elastomer B is 1 - 2:1.

[0009] Further, the dielectric elastomer A and the dielectric elastomer B are each one or several of polyurethane elastomer, acrylate elastomer, silicone elastomer, and transparent epoxy resin elastomer.

[0010] Further, both the dielectric elastomer polymer A and the dielectric elastomer polymer B include a dielectric elastomer polymer and a solvent, and the mass ratio of the dielectric elastomer polymer to the solvent is 1:0.1 to 5;

[0011] The dielectric elastomer polymers are each one or a mixture of several of polyethylene, polyvinyl alcohol, polyvinyl butyral, polydimethylsiloxane, styrene-isoprene-styrene block copolymer, ethylene-vinyl acetate copolymer, and styrene-butadiene-styrene block copolymer;

[0012] The solvent is one or several of deionized water, toluene, ethanol, acetone, isopropanol, ether, dichloromethane, tetrahydrofuran, and benzoyl peroxide.

[0013] Further, the near-infrared mechanoluminescent powder includes CaZnOS:Nd 3+ , CaZnOS:Pr 3+ , CaZnOS:Er 3+ , LiGa5O8:Pr 3+ , LiNbO3:Nd 3+ , Sr3Sn2O7:Nd 3+ , SrZnSO:Nd 3+ , SrAl2O4:Er 3+ , SrZn2S2O:Yb 3+ , SrAl2O4:Nd 3+ , Mg3Ga2GeO8:Cr 3+ , MgGa2O4:Cr 3+ , Ca 0.8 , Sr 0.2 , MgSi2O6:Cr 3+ , LaAlO3:Cr 3+ , YAlO3:Cr 3+ or several of them.

[0014] A method for preparing a near-infrared mechanoluminescent film based on stress excitation, which is characterized by including the following steps:

[0015] Step 1: After separately weighing the dielectric elastomer polymer A, the dielectric elastomer polymer B, and the near-infrared mechanoluminescent powder, place the near-infrared mechanoluminescent powder in an oven for drying, and pour it into an agate mortar and grind it with absolute ethanol as the medium;

[0016] Step 2: Place the well-ground near-infrared mechanoluminescent powder in an oven for drying;

[0017] Step 3: Perform defoaming treatment on the dielectric elastomer A and the dielectric elastomer B respectively to obtain the polymer solution A and the polymer solution B; mix the polymer solution B and the near-infrared mechanoluminescent powder, stir, perform ultrasonic dispersion and defoaming to obtain the polymer solution C;

[0018] Step 4: Pour an appropriate amount of the polymer solution A into a mold and perform heat treatment to obtain a semi-cured flexible base layer; pour the polymer solution C onto the upper surface of the semi-cured flexible base layer in the mold, and perform heat treatment to obtain a semi-cured near-infrared elastic layer; pour the remaining polymer solution A onto the semi-cured near-infrared elastic layer, place it in an oven for drying and curing, and demold to obtain a near-infrared mechanoluminescent film.

[0019] Further, the specific process of Step 1 is as follows:

[0020] Step 1.1: Weigh the dielectric elastomer A, the dielectric elastomer B, and the near-infrared mechanoluminescent powder respectively, and the mass ratio of the three is 1-2:1:0.2-4;

[0021] Step 1.2: Place the near-infrared mechanoluminescent powder in an oven for drying, the drying temperature is 50°C - 180°C, and the drying time is 40 min - 60 min;

[0022] Step 1.3: Place the near-infrared mechanoluminescent powder in an oven for drying, and pour it into an agate mortar, and grind it with absolute ethanol as the medium. Among them, the mass ratio of the near-infrared mechanoluminescent powder to absolute ethanol is 1:0.5-3; the grinding time is 30 min - 45 min.

[0023] Further, in Step 2, the drying temperature for drying the thoroughly ground near-infrared mechanoluminescent powder in an oven is 50°C - 180°C, and the drying time is 5 min - 8 min.

[0024] Further, Step 3 is specifically as follows:

[0025] Step 3.1: When the dielectric elastomer A or the dielectric elastomer B is one or several of polyurethane elastomer, acrylate elastomer, silicone elastomer, and transparent epoxy resin elastomer, perform defoaming treatment on the dielectric elastomer A or the dielectric elastomer B to obtain the polymer solution A or the polymer solution B;

[0026] When both the dielectric elastomer polymer A and the dielectric elastomer polymer B comprise a dielectric elastomer and a solvent, and the mass ratio of the dielectric elastomer to the solvent is 1:0.1 - 5, and at the same time, the dielectric elastomers are each one or a mixture of several of polyethylene, polyvinyl alcohol, polyvinyl butyral, polydimethylsiloxane, styrene-isoprene-styrene block copolymer, ethylene-vinyl acetate copolymer, styrene-butadiene-styrene block copolymer, and the solvent is one or a mixture of several of deionized water, toluene, ethanol, acetone, isopropanol, ether, dichloromethane, tetrahydrofuran, benzoyl peroxide; adding the dielectric elastomer to the solvent and stirring at 800 rpm - 900 rpm for 10 h - 24 h, and performing defoaming treatment to obtain the polymer solution A or the polymer solution B;

[0027] Step 3.2: Mix the polymer solution B and the near-infrared mechanoluminescent powder and stir at 550 rpm - 600 rpm for 1 h - 1.2 h. After ultrasonic dispersion and defoaming, obtain the polymer solution C.

[0028] Further, in step 4, the heat treatment process is as follows: Place the mold in an oven, set the temperature to 50°C - 80°C, and the heat treatment time to 1.5 h - 2 h;

[0029] Casting the polymer solution A on the semi-cured near-infrared elastic layer and placing it in an oven for drying and curing at a temperature of 50°C - 180°C for a drying time of 8 h - 12 h.

[0030] An application of a near-infrared mechanoluminescent film based on stress excitation in the fields of biomedical imaging, industry and engineering, security and anti-counterfeiting, or intelligent wearables and electronic devices.

[0031] The beneficial effects of the present invention are as follows:

[0032] The near-infrared mechanoluminescent film based on stress excitation provided by the present invention directly excites luminescence through mechanical stress, without the need for an external light source or current input, reducing energy consumption and system complexity, and also having high energy conversion efficiency and good self-excitation characteristics.

[0033] The near-infrared mechanoluminescent film based on stress excitation provided by the present invention has excellent flexibility and mechanical properties, and can adapt to complex mechanical environments and dynamic stress changes.

[0034] The preparation method of the near-infrared mechanoluminescent film based on stress excitation provided by the present invention uses a near-infrared stress luminescent powder and a highly elastic polymer in combination to obtain a deformable polymer. Then, through a layer-by-layer preparation method, an elastic film capable of generating near-infrared luminescence is prepared, wherein the luminescence is caused by the properties of the near-infrared mechanoluminescent material in the near-infrared luminescent layer; the preparation method is simple.

[0035] A near-infrared mechanoluminescent film based on stress excitation provided by the present invention has near-infrared luminescence characteristics, enabling it to have broad application prospects in the fields of biomedical imaging, structural health monitoring, stress sensing, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic structural diagram of Embodiment 1 of a near-infrared mechanoluminescent film based on stress excitation of the present invention;

[0037] Figure 2 is the luminescence spectrum obtained from the photoluminescence test and mechanoluminescence test when the doping concentration of Cr in a near-infrared mechanoluminescent film prepared in Embodiment 1 of the present invention is 0.6%; 3+

[0038] Figure 3 is a comparative force-induced luminescence spectrogram of a near-infrared mechanoluminescent film prepared in Embodiment 2 of the present invention under 10 N pressure with and without ultraviolet irradiation;

[0039] Figure 4 is a graph showing the change in luminescence intensity of a near-infrared mechanoluminescent film prepared in Embodiment 3 of the present invention at different wavelengths under 20 N pressure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] To make the objectives, advantages, and features of the present invention clearer, the following further elaborates on a near-infrared mechanoluminescent film based on stress excitation of the present invention, its preparation method, and applications in conjunction with the accompanying drawings and specific embodiments. According to the following detailed description, the advantages and features of the present invention will be clearer.

[0041] Embodiment 1

[0042] In this embodiment, a near-infrared mechanoluminescent film based on stress excitation is provided, and the structure is as Figure 1 shown.

[0043] The preparation method of the near-infrared mechanoluminescent film based on stress excitation in this Embodiment 1 is as follows:

[0044] Weigh 0.5 g of near-infrared force-induced luminescence powder LaAlO3:Cr 3+ , place it in an oven for drying, the drying temperature is 120 °C, the drying time is 56 min, and pour it into an agate mortar, add 1 g of absolute ethanol as a medium for grinding, and grind for 35 min. Place the well-ground near-infrared force-induced luminescence powder in the oven for drying at a drying temperature of 103 °C and a drying time of 5 min.

[0045] Pour 0.5 g of styrene-isoprene-styrene block copolymer and 0.5 g of ethylene-vinyl acetate copolymer into 3.2 g of toluene, mix and stir for 24 h, with the stirring speed of the stir bar being 900 rpm, and conduct defoaming treatment to obtain polymer solution A with self-healing property and stretchability.

[0046] Mix and stir 0.5 g of polydimethylsiloxane (PDMS) and 2 g of benzoyl peroxide for 10 h, with the stirring speed being 800 rpm, and conduct defoaming treatment to obtain polymer solution B.

[0047] Add 0.5 g of dried near-infrared mechanoluminescent powder LaAlO3:Cr into the obtained polymer solution B 3+ , stir at a speed of 600 rpm for 1 h, and after ultrasonic dispersion and defoaming, polymer solution C with mechanoluminescent property can be obtained.

[0048] Pour polymer solution A into a suitable mold, place it in an oven, set the temperature to 60 °C and the time to 2 h to obtain a semi-cured flexible base layer; pour polymer solution C onto the upper surface of the semi-cured flexible base layer in the mold, and after setting the temperature to 75 °C and the time to 2 h, a semi-cured near-infrared elastic layer is obtained; pour the remaining polymer solution A onto the semi-cured near-infrared elastic layer, put it into the oven, with the drying and curing temperature being 105 °C and the drying time being 10 h, then a near-infrared mechanoluminescent film is obtained.

[0049] The mold used in this example is a mold with a rectangular groove, and its size is selected according to the actual size of the film required.

[0050] Take two near-infrared mechanoluminescent films obtained in this example and conduct photoluminescence test and mechanoluminescence test. When the doping concentration of Cr 3+ is 0.6%, the irradiation wavelength of the photoluminescence test group is 254 nm, and a force of 25 N is applied to the mechanoluminescence test group. The obtained luminescence spectrogram is as Figure 2 shown, where ML is the luminescence spectrum transformation curve obtained by the mechanoluminescence test group, PL is the luminescence spectrum transformation curve obtained by the photoluminescence test group, the abscissa is the luminescence wavelength of the film, and the ordinate is the luminescence intensity.

[0051] According to Figure 2 it can be known that the mechanoluminescence intensity of the near-infrared mechanoluminescent film based on stress excitation of the present invention can also reach the level of photoluminescence.

[0052] Example 2

[0053] In this example, a near-infrared mechanoluminescent film based on stress excitation is provided, and the preparation method is as follows:

[0054] Weigh 2 g of the near-infrared stress-induced luminescence powder MgGa2O4:Cr 3+ , place it in an oven for drying. The drying temperature is 90 °C and the drying time is 50 min. Then pour it into an agate mortar, add 0.5 g of absolute ethanol as a medium for grinding, and grind for 35 min. Place the well-ground near-infrared stress-induced luminescence powder in the oven for drying at a temperature of 103 °C and a drying time of 5 min.

[0055] Pour 0.4 g of styrene-isoprene-styrene block copolymer and 0.6 g of ethylene-vinyl acetate copolymer into 2 g of toluene, mix and stir for 24 h. The rotation speed of the stir bar is 800 rpm, and defoaming treatment is carried out to obtain a polymer solution A with self-healing and stretchability.

[0056] Carry out defoaming treatment on 0.5 g of polyurethane elastomer to obtain a polymer solution B.

[0057] Add the ground and dried near-infrared stress-induced luminescence powder MgGa2O4:Cr 3+ to the obtained polymer solution B, stir at a speed of 600 rpm for 1 h, and after ultrasonic dispersion and defoaming, a polymer solution C with stress-induced luminescence performance can be obtained.

[0058] Pour the polymer solution A into a suitable mold, place it in an oven, set the temperature to 75 °C and the time to 2 h to obtain a semi-cured flexible base layer; pour the polymer solution C into the mold, and after setting the temperature to 72 °C and the time to 2 h, obtain a semi-cured near-infrared elastic layer; pour the remaining polymer solution A onto the semi-cured near-infrared elastic layer, place it in an oven, and the drying and curing temperature is 110 °C and the drying time is 10.5 h to obtain a near-infrared mechanoluminescent film.

[0059] Take two near-infrared mechanoluminescent films prepared in this example based on stress excitation. One film is irradiated with ultraviolet light with a wavelength of 254 nm for 3 min under a pressure of 10 N, and the other film is not irradiated with ultraviolet light under a pressure of 10 N. The obtained stress-induced luminescence spectra are as Figure 3 shown, where UV 3 min is the curve obtained by ultraviolet irradiation, No UVirradiation is the curve obtained without ultraviolet irradiation. The abscissa is the emission wavelength and the ordinate is the emission intensity.

[0060] According to Figure 3 the changing trends of the two curves, it can be seen that after ultraviolet light irradiation, the traps in the stress-induced luminescence powder can be replenished, and the luminescence intensity can be enhanced.

[0061] Example 3

[0062] In this embodiment, a near-infrared mechanoluminescent film based on stress excitation is provided, and the preparation method is as follows:

[0063] Weigh 2 g of near-infrared force-induced luminescence powder Mg3Ga2GeO8:Cr 3+ , place it in an oven for drying, the drying temperature is 157 °C, the drying time is 60 min, and pour it into an agate mortar. Add 0.6 g of absolute ethanol as a medium for grinding, and grind for 45 min. The near-infrared force-induced luminescence powder after sufficient grinding is placed in an oven for drying at a drying temperature of 115 °C and a drying time of 6 min.

[0064] Perform defoaming treatment on 2.74 g of transparent epoxy resin elastomer to obtain polymer solution A with self-healing and stretchability.

[0065] Mix 0.2 g of polydimethylsiloxane (PDMS) and 0.8 g of benzoyl peroxide in proportion and stir for 10 h, the stirring speed is 900 rpm, to obtain polymer solution B.

[0066] In the obtained polymer solution B, add the ground and dried near-infrared force-induced luminescence powder Mg3Ga2GeO8:Cr 3+ , stir at a speed of 600 rpm for 1 h, after ultrasonic dispersion and defoaming, a polymer solution C with force-induced luminescence performance can be obtained.

[0067] Pour polymer solution A into a suitable mold, place it in an oven, and set the temperature to 60 °C and the time to 2 h to obtain a semi-cured flexible base layer; pour polymer solution C into the mold, and set the temperature to 70 °C and the time to 2 h to obtain a semi-cured near-infrared elastic layer; pour the remaining polymer solution A on the semi-cured near-infrared elastic layer and place it in an oven, the drying and curing temperature is 120 °C and the drying time is 8 h, then the near-infrared mechanoluminescent film is obtained.

[0068] Apply a pressure of 20 N to the near-infrared mechanoluminescent film based on stress excitation prepared in this embodiment, and the curve of the change in luminescence intensity at different luminescence wavelengths is as Figure 4 shown. According to Figure 4 , it can be known that when the wavelength is 720 nm to 800 nm, the luminescence intensity of the near-infrared mechanoluminescent film based on stress excitation is the most obvious.

[0069] In the above manner, a near-infrared mechanoluminescent film based on stress excitation according to the present invention is obtained by blending a near-infrared stress luminescent powder and a polymer with high elasticity to obtain a deformable polymer. An elastic film capable of emitting near-infrared light is prepared by a layer-by-layer preparation method. Among them, the luminescence is caused by the performance of the near-infrared force-induced luminescent material in the near-infrared luminescent layer. The elastic film obtained by the present invention emits light directly through mechanical stress, without an external power supply or light source, reducing energy consumption and system complexity. It has excellent flexibility and mechanical properties and can adapt to complex mechanical environments and dynamic stress changes. In addition, the near-infrared luminescence characteristics of the film make it have broad application prospects in the fields of biomedical imaging, structural health monitoring, stress sensing, etc.

[0070] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting the present application; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A near-infrared mechanoluminescent film based on stress excitation, characterized in that: It includes a first flexible base layer, a near-infrared light-emitting layer, and a second flexible base layer that are sequentially covered on the first flexible base layer from bottom to top; The raw materials of the first flexible base layer and the second flexible base layer are dielectric elastomer A. The thickness of the first flexible base layer is 100 - 1000 μm, and the thickness of the second flexible base layer is 100 - 500 μm; The raw materials of the near-infrared light-emitting layer are dielectric elastomer B and near-infrared mechanoluminescent powder. The mass ratio of dielectric elastomer B to near-infrared mechanoluminescent powder is 1:0.2 - 4; the thickness of the near-infrared light-emitting layer is 0.98 mm - 1.1 mm; The mass ratio of dielectric elastomer A to dielectric elastomer B in the first flexible base layer and the second flexible base layer is 1 - 2:

1.

2. The near-infrared mechanoluminescent film based on stress excitation according to claim 1, wherein: Both dielectric elastomer A and dielectric elastomer B are one or several of polyurethane elastomer, acrylate elastomer, silicone elastomer, and transparent epoxy resin elastomer.

3. The near-infrared mechanoluminescent thin film based on stress excitation according to claim 1, wherein: Both dielectric elastomer A and dielectric elastomer B include a dielectric elastomer and a solvent, and the mass ratio of the dielectric elastomer to the solvent is 1:0.1 - 5; The dielectric elastomers are all one or several mixtures of polyethylene, polyvinyl alcohol, polyvinyl butyral ester, polydimethylsiloxane, styrene-isoprene-styrene block copolymer, ethylene-vinyl acetate copolymer, and styrene-butadiene-styrene block copolymer; The solvent is one or several of deionized water, toluene, ethanol, acetone, isopropanol, ether, dichloromethane, tetrahydrofuran, and benzoyl peroxide.

4. The near-infrared mechanoluminescent film based on stress excitation according to claim 1, wherein: The near-infrared force-induced luminescence powder includes CaZnOS:Nd 3+ , CaZnOS:Pr 3+ , CaZnOS:Er 3+ , LiGa5O8:Pr 3+ , LiNbO3:Nd 3+ , Sr3Sn2O7:Nd 3+ , SrZnSO:Nd 3+ , SrAl2O4:Er 3+ , SrZn2S2O:Yb 3+ , SrAl2O4:Nd 3+ , Mg3Ga2GeO8:Cr 3+ , MgGa2O4:Cr 3+ , Ca 0.8 Sr 0.2 , MgSi2O6:Cr 3+ , LaAlO3:Cr 3+ , YAlO3:Cr 3+ One or more of the above.

5. A method for preparing a stress-excited near-infrared mechanoluminescent film according to any one of claims 1-4, characterized in that, It includes the following steps: Step 1: After separately weighing dielectric elastomer A, dielectric elastomer B, and near-infrared mechanoluminescent powder, place the near-infrared mechanoluminescent powder in an oven for drying, and pour it into an agate mortar for grinding with absolute ethanol as the medium; Step 2: Place the well-ground near-infrared mechanoluminescent powder in an oven for drying; Step 3: Perform defoaming treatment on dielectric elastomer A and dielectric elastomer B respectively to obtain polymer solution A and polymer solution B; mix polymer solution B and near-infrared mechanoluminescent powder, stir, perform ultrasonic dispersion and defoaming to obtain polymer solution C; Step 4: Pour an appropriate amount of polymer solution A into a mold for heat treatment to obtain a semi-cured flexible base layer; pour polymer solution C onto the upper surface of the semi-cured flexible base layer in the mold, and perform heat treatment to obtain a semi-cured near-infrared elastic layer; pour the remaining polymer solution A onto the semi-cured near-infrared elastic layer, place it in an oven for drying and curing, demold to obtain a near-infrared mechanoluminescent film.

6. The preparation method of a near-infrared mechanoluminescent film based on stress excitation according to claim 5, characterized in that, The specific process of Step 1 is as follows: Step 1.1: Separately weigh dielectric elastomer A, dielectric elastomer B, and near-infrared mechanoluminescent powder, and their mass ratio is 1 - 2:1:0.2 - 4; Step 1.2: Place the near-infrared mechanoluminescent powder in an oven for drying, the drying temperature is 50°C - 180°C, and the drying time is 40 min - 60 min; Step 1.3: Place the near-infrared mechanoluminescent powder in an oven for drying, then pour it into an agate mortar and grind it with absolute ethanol as the medium. Here, the mass ratio of the near-infrared mechanoluminescent powder to absolute ethanol is 1:0.5 - 3; the grinding time is 30 min - 45 min.

7. The preparation method of a near-infrared mechanoluminescent film based on stress excitation according to claim 5, characterized in that: In Step 2, the drying temperature for drying the well-ground near-infrared mechanoluminescent powder in an oven is 50°C - 180°C, and the drying time is 5 min - 8 min.

8. The preparation method of a near-infrared mechanoluminescent thin film based on stress excitation according to claim 5, wherein, Step 3 is specifically as follows: Step 3.1: When dielectric elastomer A or dielectric elastomer B is one or several of polyurethane elastomer, acrylate elastomer, silicone elastomer, and transparent epoxy resin elastomer, perform defoaming treatment on dielectric elastomer A or dielectric elastomer B to obtain polymer solution A or polymer solution B; When both dielectric elastomer A and dielectric elastomer B include a dielectric elastomer and a solvent, and the mass ratio of the dielectric elastomer to the solvent is 1:0.1 - 5. At the same time, the dielectric elastomers are one or several mixtures of polyethylene, polyvinyl alcohol, polyvinyl butyral, polydimethylsiloxane, styrene-isoprene-styrene block copolymer, ethylene-vinyl acetate copolymer, and styrene-butadiene-styrene block copolymer, and the solvent is one or several mixtures of deionized water, toluene, ethanol, acetone, isopropanol, ether, dichloromethane, tetrahydrofuran, and benzoyl peroxide; add the dielectric elastomer to the solvent and stir at 800 rpm - 900 rpm for 10 h - 24 h, and then perform defoaming treatment to obtain polymer solution A or polymer solution B; Step 3.2: Mix polymer solution B and the near-infrared mechanoluminescent powder and stir at 550 rpm - 600 rpm for 1 h - 1.2 h. After ultrasonic dispersion and defoaming, obtain polymer solution C.

9. The preparation method of a near-infrared mechanoluminescent film based on stress excitation according to claim 5, characterized in that: In Step 4, the heat treatment process is as follows: Place the mold in an oven, set the temperature to 50°C - 80°C, and the heat treatment time is 1.5 h - 2 h; The drying and curing temperature for casting polymer solution A on the semi-cured near-infrared elastic layer in an oven is 50°C - 180°C, and the drying time is 8 h - 12 h.

10. Use of the stress-excited near-infrared mechanoluminescent film according to claim 1 in the fields of biomedical imaging, industry and engineering, security and anti-counterfeiting, or smart wearable and electronic devices.

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