阅读说明：本技术 一种生物相容性和柔性好的弹性压电膜及其制备方法与应用 (Elastic piezoelectric film with good biocompatibility and flexibility and preparation method and application thereof ) 是由 苟雪 朱子馨 万正军 周俊余 范端 罗胜年 于 2021-09-15 设计创作，主要内容包括：本发明提供了一种生物相容性和柔性好的弹性压电膜及制备方法与应用。本发明的生物相容性和柔性好的弹性压电膜是将钛酸钡纳米颗粒嵌入聚二甲基硅氧烷弹性基底膜表面,得到复合弹性压电膜,然后将聚多巴胺沉积在复合弹性压电膜表面,得到所述弹性压电膜。本发明发现,经过多巴胺改性的压电膜能为细胞提供更好的黏附界面,促进了细胞肌动蛋白束的形成和粘着斑的形成,且细胞与弹性膜上压电纳米颗粒相互作用时,会产生一定的压电电势,进一步刺激细胞的黏附行为；另一方面,本发明压电材料表现出很好的柔韧性,是一种柔性传感器件。本发明为压电材料在组织修复、再生医学、生物电子、柔性传感器件和压电纳米发电机等方面的应用提供了理论基础。(The invention provides an elastic piezoelectric film with good biocompatibility and flexibility, a preparation method and application thereof. The elastic piezoelectric film with good biocompatibility and flexibility is obtained by embedding barium titanate nano-particles into the surface of a polydimethylsiloxane elastic basement membrane to obtain a composite elastic piezoelectric film, and then depositing polydopamine on the surface of the composite elastic piezoelectric film. The invention discovers that the dopamine-modified piezoelectric membrane can provide a better adhesion interface for cells, promotes the formation of actin bundles and adhesion spots of the cells, and generates a certain piezoelectric potential to further stimulate the adhesion behavior of the cells when the cells interact with the piezoelectric nanoparticles on the elastic membrane; on the other hand, the piezoelectric material of the invention shows good flexibility and is a flexible sensing device. The invention provides a theoretical basis for the application of the piezoelectric material in the aspects of tissue repair, regenerative medicine, bioelectronics, flexible sensing devices, piezoelectric nano-generators and the like.)

1. A preparation method of an elastic piezoelectric film with good biocompatibility and flexibility is characterized in that barium titanate nano-particles are embedded into the surface of a polydimethylsiloxane elastic basement membrane to obtain a composite elastic piezoelectric film, and then polydopamine is deposited on the surface of the composite elastic piezoelectric film to obtain the elastic piezoelectric film.

2. A method for preparing an elastic piezoelectric film with good biocompatibility and flexibility is characterized by comprising the following steps:

(1) mixing the polydimethylsiloxane prepolymer with a curing agent, uniformly stirring, and then paving in a mold to obtain a layer of film;

(2) vacuumizing the mould with the film formed in the step (1), then putting the mould into an air-blast drying oven, and drying the mould at 70 ℃ for 25min to a semi-solidified state;

(3) ultrasonically dispersing barium titanate in absolute ethyl alcohol, adding the obtained mixture to the surface of the film of the mould treated in the step (2), and then putting the mould into a forced air drying oven to be cured for 2 hours at 70 ℃; obtaining a composite elastic piezoelectric film of barium titanate and polydimethylsiloxane after solidification;

(4) dissolving dopamine in a Tris buffer solution with the pH value of 8.5 to prepare a dopamine solution with the concentration of 1 mg/ml; fully stirring the prepared dopamine solution, then immersing the composite elastic piezoelectric film obtained in the step (3) in the dopamine solution, and carrying out immersion treatment at 30 ℃ for 12-24 hours to obtain the elastic piezoelectric film.

3. The production method according to claim 2, wherein the mass ratio of the polydimethylsiloxane prepolymer to the curing agent in the step (1) is 10: 1; the stirring time is 10 min.

4. The preparation method according to claim 2, wherein the vacuum-pumping treatment in the step (2) is to place the mold into a pressure tank and perform vacuum-pumping treatment by using a vacuum pump; standing for 50min after vacuum-pumping treatment.

5. The preparation method according to claim 2, wherein the mass-to-volume ratio of the barium titanate to the absolute ethyl alcohol in the step (3) is 2:1 to 6:1 mg/ml.

6. The production method according to claim 2, wherein the time for the ultrasonic dispersion in the step (3) is 20 min.

7. The method according to claim 2, wherein the sufficient stirring in step (4) is performed by stirring the prepared dopamine solution at 30 ℃ for 30 min.

8. The preparation method according to claim 2, wherein in the step (4), the composite elastic piezoelectric film is cut into square small pieces, cleaned with deionized water, and then immersed in the dopamine solution.

9. An elastic piezoelectric film with good biocompatibility and flexibility, prepared by the method of any one of claims 1 to 8.

10. Use of a biocompatible and flexible elastic piezoelectric film according to claim 9, wherein said use comprises use of the elastic piezoelectric film in tissue repair materials, flexible sensing devices or piezoelectric nano-generators.

Technical Field

The invention belongs to the technical field of piezoelectric materials, and particularly relates to an elastic piezoelectric film with good biocompatibility and flexibility, a preparation method and application thereof.

Background

The bone is considered as a biological piezoelectric material, has a remarkable piezoelectric effect, the piezoelectric effect is derived from the collagen component of the bone, and the normal physiological activity and metabolism of the bone can be maintained by completing the interconversion of mechanical energy and electric energy, and the bone shaping, reconstruction and function maintenance are facilitated. Therefore, the development of materials with piezoelectric properties as bone repair materials can help to simulate in vivo microenvironments.

The traditional piezoelectric material mainly regulates and controls piezoelectric signals by means of additional mechanical loading, magnetic fields or ultrasound and the like. In recent years, the piezoelectric self-stimulation mediated by cell adhesion provides a new opportunity for future medical treatment based on bioelectric stimulation. In particular, the local electric field is mainly determined by the piezoelectric properties inherent in the biomaterial and the dynamic adhesion of the cells. The electricity generation mode does not need to apply an external physical field, and can perform noninvasive regulation and control on cell and tissue behaviors. Therefore, the development of an efficient and optimized piezoelectric material interface has important significance for cell regulation.

On the other hand, most of the conventional sensing materials are based on metal and semiconductor materials, the application of the conventional sensing materials is greatly limited by the rigidity and low sensitivity of the conventional sensing materials, and a sensing device with good flexibility also becomes a research direction for which a breakthrough is needed. Compared with the traditional silicon-based electronic device, the flexible electronic device has strong conformality to different interfaces, and has good fitting performance to soft or hard interfaces, planes or curved surfaces. This unique advantage has led to extensive research and application of flexible electronic devices in a variety of fields.

Along with the improvement of the living standard and the living quality of people, the intelligent wearable equipment starts to rush into the public life and is rapidly developed, and the demand on the flexible durable power supply is continuously increased. Pressure sensors that convert pressure input into electrical signals are important members of the flexible electronics family. As one of the most important flexible electronic devices, the flexible pressure sensor can be attached to any curved surface, and can efficiently detect various human activities including physical, chemical, biological and environmental status signals of human bodies. Flexible sensors, particularly flexible pressure sensors, will find increasingly widespread application in the fields of health monitoring, wearable electronics, and electronic skin, among others. Among them, improving the sensitivity of the sensor and widening the operating range by using the microstructure are still challenging tasks.

Since the first bright phase of the piezoelectric nano generator in 2006, various piezoelectric materials are applied to the field, and the preparation process and the device structure of the piezoelectric nano generator are continuously optimized. Meanwhile, researchers are continuously developing new piezoelectric materials by using new methods to improve the performance of the piezoelectric nano-generator. The piezoelectric material plays a decisive role in performance of the piezoelectric nano generator, the piezoelectric nano generator developed by utilizing different piezoelectric materials has completely different performances, and the piezoelectric effect of the material deeply influences the final performance of the prepared piezoelectric nano generator. Research conditions in recent years show that most researchers put the entry point for improving the performance of the piezoelectric nano-generator into the piezoelectric material, and integrate a plurality of materials in the same nano-generator through various processes so as to endow the same with multi-source acquisition capability and excellent output performance.

In conclusion, new piezoelectric materials are continuously developed, and how to develop new piezoelectric materials, so that the materials have good biocompatibility and higher flexibility, can be well used for tissue repair materials, can also be well used in the fields of flexible sensing devices, piezoelectric nano-generators and the like, and becomes a technical problem to be solved urgently.

Disclosure of Invention

The present invention is directed to solving the above-mentioned problems, and therefore, a novel elastic piezoelectric film material is provided, which is an elastic piezoelectric film with good biocompatibility and high flexibility, and can be well used in the fields of tissue repair materials, flexible sensing devices, piezoelectric nano-generators, and the like. The invention also provides a preparation method and application of the elastic piezoelectric film.

The invention aims to provide a preparation method of an elastic piezoelectric film with good biocompatibility and flexibility.

The preparation method of the elastic piezoelectric film with good biocompatibility and flexibility, provided by the invention, is characterized in that barium titanate nanoparticles are embedded into the surface of a Polydimethylsiloxane (PDMS) elastic basement membrane, and dopamine is polymerized into Polydopamine (PDA) through self-polymerization and deposited on the surface of the material to improve the surface hydrophilicity, so that the elastic piezoelectric film with good biocompatibility is formed.

Although barium titanate HAs been studied for its piezoelectric effect and HAs been used by researchers for preparing composite piezoelectric materials, HA (hydroxyapatite), which is an inorganic component of bone, and BaTiO (barium titanate) having piezoelectric effect have been used in Master papers of Wucmo and Marinin, both of Western medicine university₃Compounding to prepare BaTiO₃the/HA composite biological piezoelectric ceramic simulates inorganic components of human bonesAnd the piezoelectric effect of human bones, but the composite biological piezoelectric ceramic material has insufficient flexibility and cannot be used in the fields of flexible sensing devices and piezoelectric nano generators.

The work of the super-hydrophobic surface of a PDMS film is researched in doctor paper of Longmengying shadow of south China university, zinc hydroxystannate particles with flame retardant property are introduced for the first time, and the flame retardant property is endowed to the super-hydrophobic coating. The Master papers of the application of Hubei university of industry have studied that PDMS with good biocompatibility and stretchability is used as a polymer matrix, and several flexible strain-sensitive conductive polymer composite materials with different layered structures are constructed by adopting the strategies of swelling and penetration, natural sedimentation, magnetic field assistance and the like, so as to realize the high conductivity, high sensitivity and high working strain of the composite materials, and the composite materials are better applied to human motion monitoring. However, the material does not have cell adhesion, cannot be well used for an adhesive tissue engineering material due to the super-hydrophobic property of the surface of the material, cannot generate piezoelectric potential in the tissue repair process, and cannot effectively exert the characteristics of the piezoelectric material.

In order to endow the flexible PDMS composite material with a good piezoelectric effect and certain cell adhesion, the inventor compounds the flexible PDMS composite material with the piezoelectric material and selects a class of adhesive with adhesion characteristics for testing, however, disappointing that other classes of adhesives cannot form the interaction of piezoelectric signals to an adhesion interface and cannot generate piezoelectric potential on the cell surface when combined with PDMS and the piezoelectric material, and the flexible PDMS composite material has no promotion effect on the growth and adhesion of cells.

When the method is adopted, barium titanate nanoparticles are embedded into the surface of a PDMS elastic basement membrane, and the dopamine is self-polymerized into polydopamine PDA which is deposited on the surface of a material, the applicant finds that a piezoelectric membrane modified by dopamine can provide a better adhesion interface for cells, promotes the formation of actin bundles of the cells and the formation of adhesion spots, and generates a certain piezoelectric potential when the cells interact with the piezoelectric nanoparticles on the elastic membrane, so that the adhesion behavior of the cells is further stimulated, the growth and adhesion of the cells are facilitated, and the finding provides a new idea for the development of the piezoelectric material.

The above findings indicate that the elastic piezoelectric film of the present invention can be well used in the fields of tissue repair materials, flexible sensing devices, piezoelectric nanogenerators, and the like. The existing piezoelectric materials are difficult to be simultaneously applied to the fields, and the superiority of the elastic piezoelectric film material is shown.

Specifically, the preparation method provided by the invention comprises the following steps:

(1) preparation of polydimethylsiloxane elastic base film: mixing the polydimethylsiloxane prepolymer with a curing agent, uniformly stirring, and then paving in a mold to obtain a layer of film;

(2) vacuumizing the mould with the film formed in the step (1), standing, then putting into an air-blast drying oven, and drying at 70 ℃ for 25min to a semi-solidified state;

(3) ultrasonically dispersing barium titanate in absolute ethyl alcohol, adding the obtained mixture to the surface of the film of the mould treated in the step (2), and then putting the mould into a forced air drying oven to be cured for 2 hours at 70 ℃; obtaining a composite elastic piezoelectric film of barium titanate and polydimethylsiloxane after solidification;

(4) dissolving dopamine in a Tris buffer solution with the pH value of 8.5 to prepare a dopamine solution with the concentration of 1 mg/ml; fully stirring the prepared dopamine solution, then immersing the composite elastic piezoelectric film obtained in the step (3) in the dopamine solution, and carrying out immersion treatment at 30 ℃ for 12-24 hours to obtain the elastic piezoelectric film.

According to the elastic piezoelectric film and the preparation method thereof provided by the invention, high-elasticity PDMS is used as a flexible matrix, nano barium titanate is used as a piezoelectric material, a volatile solvent is adopted to disperse nano barium titanate particles, then the barium titanate particles are deposited on the surface of uncured PDMS through a natural sedimentation method, and the solvent is volatilized in the process of heating and curing PDMS, so that the barium titanate particles are fixed on the surface of PDMS to form the elastic piezoelectric film.

The present inventors found that nano barium titanate can enter the surface and the interior of PDMS by natural sedimentation, a small amount of barium titanate is diffused into the interior region of PDMS, and most of barium titanate remains in the surface layer. The barium titanate is enriched in the surface layer, so that the piezoelectric property of the material is ensured, and the surface layer with high barium titanate content is sensitive to strain, thereby being beneficial to realizing the piezoelectric effect. The lower content of barium titanate in the PDMS is beneficial to keeping the good stretchability and flexibility of the PDMS.

Further, the mass ratio of the polydimethylsiloxane prepolymer to the curing agent in the step (1) is 10: 1; the stirring time is 10 min.

Further, the step (2) of vacuumizing is to place the mold into a pressure tank and perform vacuumizing treatment by using a vacuum pump; the standing time is 50 min.

Further, in the step (3), the mass-to-volume ratio of the barium titanate to the absolute ethyl alcohol is 2: 1-6: 1 mg/ml.

Further, the time of the ultrasonic dispersion in the step (3) is 20 min.

Further, the fully stirring in the step (4) is to stir the prepared dopamine solution at 30 ℃ for 30 min.

Further, in the step (4), the composite elastic piezoelectric film is cut into square small blocks, washed by deionized water and then immersed in a dopamine solution.

The invention also aims to provide the elastic piezoelectric film which is prepared by the method and has good biocompatibility and flexibility.

The invention also aims to provide application of the elastic piezoelectric film with good biocompatibility, which is application of the elastic piezoelectric film in the fields of tissue repair materials, flexible sensing devices, piezoelectric nano-generators and the like.

The invention has the following beneficial effects:

(1) the barium titanate nano particles are dispersed by absolute ethyl alcohol, then the barium titanate particles are deposited on the surface of uncured polydimethylsiloxane by a natural sedimentation method, and the barium titanate particles are fixed on the surface of the polydimethylsiloxane to form an elastic piezoelectric film along with solvent volatilization in the process of heating and curing the polydimethylsiloxane, and the absolute ethyl alcohol does not influence the subsequent experiment;

(2) the invention soaks the material in dopamine-Tris solution and utilizes dopamine autopolymerization to form polydopamine to deposit on the surface of the material, carry on the hydrophilic modification to the material and have achieved the better modified effect, can reach the best modified effect after soaking for 24h at the same time;

(3) the invention is beneficial to optimizing the design of the piezoelectric material, analyzing the feasibility of the application of the piezoelectric nano material as a biological stent and a flexible sensor and providing a theoretical basis for the application of the piezoelectric material in the aspects of tissue repair, flexible sensing devices, piezoelectric nano generators and the like.

Drawings

FIG. 1 is a schematic view of a process for preparing an elastic piezoelectric film material according to the present invention;

FIG. 2 is a surface SEM image of a piezoelectric elastic membrane with different mass barium titanate particles added on the surface of a PDMS membrane with the same area; a) a pure PDMS membrane; b) and c) and d) are elastic piezoelectric films containing 20mg, 40mg, and 60mg of barium titanate, respectively.

Fig. 3 shows the surface contact angles of a pure PDMS film and an elastic piezoelectric film with 20mg, 40mg, 60mg barium titanate particles added, which are not modified (a, b, c, d) and soaked for 24h (e, f, g, h).

FIG. 4 shows the death and viability of MSCs cells after 24h of surface culture on pure PDMS membranes (a modified, b unmodified) and elastic piezoelectric membranes (c modified, d unmodified) with 40mg barium titanate content.

FIG. 5 is a staining pattern of cytoskeleton and nucleus of MSCs after culturing on the surface of pure PDMS membrane (a unmodified, b modified) and elastic piezoelectric membrane (c unmodified, d modified) added with barium titanate content of 40mg for 24 h.

FIG. 6 shows the spread area of MSCs cells cultured on the surface of unmodified and modified PDMS membrane and elastic piezoelectric membrane with barium titanate content of 40mg for 24 h.

FIG. 7 shows the electrical output performance of different PDMS membrane materials, PDMS @ BTO_s、[email protected]_d、[email protected]_d+sRespectively indicating pure PDMS, embedding barium titanate, PDMS mixed barium titanate and PDMS mixed barium titanate on the surface of PDMS, and then embedding barium titanate on the surface of PDMS; a: the electrical output of the different materials under 10N force, 2Hz frequency loading, [email protected]_d+sThe output performance of the material is good; b: PDMS @ BTO_d+sOutput at 10N force, different loading frequencies, indicated PDMS @ BTO_d+sThe piezoelectric nano generator or the piezoelectric sensor made of the material can collect low-frequency signals; c: the cycle experiment under the loading of 1Hz shows that PDMS @ BTO_d+sThe device made of the material has stable output.

FIG. 8 is PDMS @ BTO_d+sTesting the flexibility of the material; wherein a is a raw material, and b, c and d are respectively bending, stretching and twisting tests of the raw material.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is described in detail below with reference to the following embodiments, and it should be noted that the following embodiments are only for explaining and illustrating the present invention and are not intended to limit the present invention. The invention is not limited to the embodiments described above, but rather, may be modified within the scope of the invention.

Example 1

A method for preparing an elastic piezoelectric film with good biocompatibility and flexibility comprises the following steps:

(1) preparation of elastic substrates

The beaker and the culture dish (60mm × 15mm) required by the experiment are cleaned by deionized water and dried for standby. Weighing proper amount of Polydimethylsiloxane (PDMS) prepolymer by an electronic balance, placing into a beaker, recording the mass of PDMS, zeroing the electronic balance, and adding curing agent (matching product of PDMS, product name: SYLGARD) into the beaker by a rubber head dropper^TM184Silicone Elastomer Base) to finally make the mass ratio of PDMS to curing agent 10: 1; stirring with a glass rod at a uniform speed for 10min to fully mix the PDMS prepolymer in the beaker with the curing agent; pouring PDMS uniformly mixed with a curing agent into a culture dish, and enabling the PDMS to flow and spread over the bottom of the whole culture dish under the action of gravity, wherein the pouring amount is suitable for enabling the PDMS to just spread a thin layer on the bottom of the culture dish (2 g in the embodiment); opening a vacuum pump head, putting the culture dish into a pressure tank, vacuumizing, and standing for 50min under a vacuum condition; however, the device is not suitable for use in a kitchenThen taking out the culture dish from the pressure tank, putting the culture dish into a forced air drying oven, and drying and curing for 2 hours at 70 ℃; after curing was complete, the PDMS was removed from the petri dish.

(2) BaTiO on surface of elastic substrate₃Adhesion of piezoelectric particles

Respectively weighing 20mg, 40mg and 60mg of barium titanate powder by using an electronic balance, putting the barium titanate powder into three clean beakers, respectively taking 10ml of absolute ethyl alcohol by using a dosing cylinder, adding the absolute ethyl alcohol into the beakers, ultrasonically dispersing for 20min, repeating the step of preparing the PDMS elastic substrate in the step (1), and after vacuumizing, putting the culture dish into an electrothermal blowing drying oven heated to 70 ℃ to be cured for 10 min; at the moment, the PDMS film in the culture dish has certain strength but the surface still has viscosity, then the culture dish is taken out from the electrothermal blowing dry box, a mixture of barium titanate and absolute ethyl alcohol is poured into the culture dish, and the beaker containing the mixture is shaken vigorously before pouring; then placing the culture dish into a forced air drying oven to be cured for 2 hours at 70 ℃; the drying temperature is lower than the boiling point of the absolute ethyl alcohol to prevent the boiling of the absolute ethyl alcohol from forming air holes in the curing process of the PDMS film; and obtaining the barium titanate PDMS composite elastic piezoelectric film after the solidification is finished.

(3) Exploration of hydrophilic modification of surface of elastic piezoelectric film by poly-dopamine

Pure PDMS film and elastic piezoelectric film added with 20mg, 40mg and 60mg are cut into square samples with the size of 1cm multiplied by 1cm, washed by deionized water, and then one of the four samples is taken and placed in a clean beaker. Weighing a proper amount of dopamine powder, placing the dopamine powder in another beaker, and adding a certain proportion of Tris buffer solution with the pH value of 8.5 for dissolution to ensure that the concentration of dopamine is 1 mg/ml. And (2) placing the prepared dopamine solution on a magnetic stirrer, stirring for 30min at 30 ℃, placing the beaker containing the dopamine solution in an electrothermal blowing drying box at the temperature of 30 ℃ after stirring is finished, immersing the square sample of the elastic piezoelectric film in the dopamine solution, sealing the opening of the beaker by using a preservative film, and taking out the sample after soaking for 12h and 24h respectively.

Experimental example 1

The pure PDMS films obtained in example 1, the elastic piezoelectric films to which the barium titanate particles of 20mg, 40mg, and 60mg were added, and the elastic piezoelectric films after the non-modification (non-dopamine-soaking) and the modification (dopamine-soaking) were subjected to performance tests, and the test results are shown in fig. 1 to 6. The stress strain testing method comprises the following steps: the dumbbell standards were drawn at a rate of 0.1mm/s on a constant moving MTS and the tension and elongation used was recorded as required during the constant draw. Other test methods were performed according to the general methods.

The experimental result shows that: the method for soaking the dopamine-Tris solution can be used for depositing the polydopamine on the surface of the material, the improvement effect on the hydrophilicity of the material is remarkable, and the contact angle of water on the surface of the material can be reduced by about 40 degrees after the material is soaked for 24 hours; meanwhile, the influence of the nano barium titanate particles adhered to the surface on the water contact angle of the surface of the material is found to be small.

The present example also unexpectedly found that hydrophilic modification of the elastic piezoelectric film of barium titanate is beneficial to the growth and adhesion of cells, the spreading area of MSCs cells (mesenchymal stem cells) on the surface of the modified material is significantly larger than that on the surface of the unmodified material, and the MSCs cells on the modified surface have better spreading state. Through experimental data analysis, the spreading area of the MSCs cells on the surface of the elastic piezoelectric film is larger than that of the MSCs cells on the surface of pure PDMS corresponding to the elastic piezoelectric film before and after modification, and it is thought that the elastic piezoelectric film can promote the adhesion and spreading of the MSCs cells, and this is probably because the barium titanate piezoelectric particles adhered on the surface of the elastic piezoelectric film are slightly deformed by the slight traction of the cells in the cell adhesion process, and because the piezoelectric effect generates a slight potential on the surface of the material, the adhesion and spreading of the cells are stimulated, so the MSCs cells on the surface of the elastic piezoelectric film have a better spreading state.

As shown in fig. 7, the electrical output performance test was performed with a sample size of 0.1cm by 1cm by 1.5cm, and the results showed: the electrical output of different materials under the loading of 10N force and 2Hz frequency shows PDMS @ BTO_d+sThe output performance of the material was good (fig. 7 a); PDMS @ BTO_d+sOutput at 10N force, different loading frequencies, indicated PDMS @ BTOd_+sThe material can be made into a piezoelectric nano generator or a piezoelectric sensor, and can collect low-frequency signals (figure 7 b); the cycle experiment under the 1Hz loading shows that PDMS @ BTO_d+sThe output of the device made of material was stable (fig. 7 c).

Taking the above dimensionsPDMS @ BTO_d+sThe sample was tested for flexibility and the results are shown in FIG. 8, where it can be seen that PDMS @ BTO_d+sThe material can be bent (fig. 8b), stretched (fig. 8c) and twisted (fig. 8d), showing good flexibility.

In conclusion, the elastic piezoelectric film material provided by the invention can be well applied to the fields of tissue repair materials, flexible sensing devices, piezoelectric nano-generators and the like.