WO2022266796A1

WO2022266796A1 - Flexible conductive biopolymer material, preparation method therefor and use thereof

Info

Publication number: WO2022266796A1
Application number: PCT/CN2021/101229
Authority: WO
Inventors: 周学昌; 宋华峰; 王海飞; 肖富瑞; 邓晓波; 陆喜
Original assignee: 深圳大学
Priority date: 2021-06-21
Filing date: 2021-06-21
Publication date: 2022-12-29

Abstract

A flexible conductive biopolymer material, a preparation method therefor and the use thereof. The preparation method therefor comprises the steps of dissolving a biopolymer in water to obtain an aqueous biopolymer solution; adding a deep eutectic solvent to the aqueous biopolymer solution, and stirring same to obtain an aqueous solution containing the deep eutectic solvent and the biopolymer; and forming the aqueous solution containing the deep eutectic solvent and the biopolymer by means of a mechanical method, and drying same to obtain the flexible conductive biopolymer material. The deep eutectic solvent and the biopolymer have a good compatibility, and a large number of hydrogen bonds in the deep eutectic solvent interact with hydrogen bonds in the biopolymer chain to form new hydrogen bonds, such that the intermolecular interaction in the biopolymer chain is reduced, the mobility of the biopolymer molecular chain is improved, the tensile strength of the biopolymer material is reduced, and the ductility of the biopolymer material is improved.

Description

A kind of flexible conductive biopolymer material and its preparation method and application

technical field

The invention relates to the field of biomaterials, in particular to a flexible conductive biopolymer material and its preparation method and application.

Background technique

Biopolymers (including silk, gelatin, starch, cellulose, sodium alginate and chitosan, etc.) are green polymer materials with good biocompatibility and degradability, and can be used as food or drug additives and Encapsulating agent can also be used as wound dressing and tissue repair material. However, biopolymers generally form hard and brittle films with poor mechanical properties and poor stability. Adding plasticizers is an effective means to solve the above problems. Commonly used plasticizers include polyols such as glycerin, mannitol, sorbitol, polyethylene glycol, and ethylene glycol, or other solvent-based molecules. However, the biopolymer materials obtained based on the current technology have high tensile strength (MPa level) and poor ductility (elongation rate is less than 50%).

Therefore, the prior art still needs to be improved and developed.

Contents of the invention

In view of the above deficiencies in the prior art, the purpose of the present invention is to provide a flexible conductive biopolymer material and its preparation method and application, aiming at solving the problems of high tensile strength and poor ductility of existing biopolymer materials.

Technical scheme of the present invention is as follows:

A first aspect of the present invention provides a method for preparing a flexible conductive biopolymer material, which includes the steps of:

Dissolving the biopolymer in water to obtain an aqueous biopolymer solution;

adding the deep eutectic solvent into the biopolymer aqueous solution, and stirring to obtain an aqueous solution containing the deep eutectic solvent and the biopolymer;

The aqueous solution containing the deep eutectic solvent and the biopolymer is mechanically shaped, and the flexible conductive biopolymer material is obtained after drying.

Optionally, the biopolymer is selected from one or more of cellulose, gelatin, chitosan, sodium alginate, carrageenan, agar, gum arabic, silk, and starch.

Optionally, the mass content of the biopolymer in the biopolymer aqueous solution is 0.1%-30%.

Optionally, the deep eutectic solvent is prepared by mixing the first component and the second component, and the first component is selected from urea, glycerin, ethylene glycol, thiourea, gluconic acid, citric acid, fructose , one or more of sorbitol, xylitol, and malic acid, and the second component is selected from one or both of amino acids and quaternary ammonium salts.

Optionally, the mass content of the first component in the deep eutectic solvent is 25%-75%.

Optionally, the amino acid is selected from one or more of glycine, alanine, and proline, and/or, the quaternary ammonium salt is selected from one or both of betaine and choline chloride kind.

Optionally, in the step of adding the deep eutectic solvent to the biopolymer aqueous solution, the quality of the deep eutectic solvent is equal to that of the biopolymer in the deep eutectic solvent and the biopolymer aqueous solution. 20%-95% of the quality and .

Optionally, the step of adding the deep eutectic solvent to the aqueous biopolymer solution also includes adding one or more of crosslinking agents, electrolytes, surfactants, and conductive nanoparticles to the biopolymer aqueous solution. in an aqueous solution of the biopolymer.

The second aspect of the present invention provides a flexible conductive biopolymer material, which is prepared by the preparation method of the flexible conductive biopolymer material described in the present invention.

The third aspect of the present invention provides an application of the flexible conductive biopolymer material described in the present invention in the preparation of flexible electronic devices.

Beneficial effects: the invention provides a flexible conductive biopolymer material and its preparation method and application. The invention uses the deep eutectic solvent as the plasticizer of the biopolymer, and the deep eutectic solvent and the biopolymer have good Compatibility, and there are a lot of hydrogen bonds in the deep eutectic solvent, which interact with the hydrogen bonds in the biopolymer chain to form new hydrogen bonds, which breaks the hydrogen bonds in the biopolymer chain and reduces the biological The intermolecular interaction within the polymer chain increases the mobility of the biopolymer molecular chain, improves the mechanical properties of the biopolymer material, reduces the tensile strength of the biopolymer material, and improves the elongation of the biopolymer material In addition, the deep eutectic solvent contains ionic electrolytes, which make the flexible conductive biopolymer material conductive, thereby realizing the preparation of flexible conductive biopolymer material.

Description of drawings

Fig. 1 is a flow chart of the preparation of the flexible conductive biopolymer material in the embodiment of the present invention.

FIG. 2 is a graph showing stress-strain test results of the flexible film material in Example 1 of the present invention.

Fig. 3 is a graph showing stress-strain test results of the flexible film material in Example 2 of the present invention.

Fig. 4 is a graph showing stress-strain test results of flexible film materials in Examples 1, 3, 4, and 5 of the present invention.

Fig. 5 is a schematic diagram of the raw materials, process, effect and application of the flexible conductive biopolymer material in the embodiment of the present invention.

detailed description

The present invention provides a flexible conductive biopolymer material and its preparation method and application. In order to make the purpose, technical solution and effect of the present invention clearer and clearer, the present invention will be further described in detail below. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

An embodiment of the present invention provides a method for preparing a flexible conductive biopolymer material, comprising the steps of:

S1, dissolving the biopolymer in water to obtain a biopolymer aqueous solution;

S2. Adding the deep eutectic solvent into the biopolymer aqueous solution, and stirring to obtain an aqueous solution containing the deep eutectic solvent and the biopolymer;

S3. Mechanically molding the aqueous solution containing the deep eutectic solvent and the biopolymer, and drying to obtain the flexible conductive biopolymer material.

In this embodiment, the biopolymer is dissolved in water to obtain a biopolymer aqueous solution, in which water is used as a co-solvent, and then the deep eutectic solvent is added to the biopolymer aqueous solution as a plasticizer for the biopolymer to form a uniform The solution is mixed, then shaped and dried by a mechanical method to obtain a flexible conductive biopolymer material, and the flexible conductive biopolymer material contains a deep eutectic solvent and a biopolymer. The deep eutectic solvent not only has a low melting point, but also contains a large number of hydrogen bonds that can interact with the hydrogen bonds in the biopolymer chain to form new hydrogen bonds, breaking the hydrogen bonds in the biopolymer chain and reducing biopolymerization. Intermolecular interactions within the chain of matter increase the mobility of the biopolymer molecular chain. In addition, compared with plasticizers in the prior art (such as single-component glycerin, mannitol, etc.), deep eutectic solvents have better compatibility with biopolymers, and the prepared flexible conductive The content of the deep eutectic solvent in the biopolymer material is as high as 95%, that is to say, the content of the plasticizer in the flexible material prepared by using the plasticizer in the prior art is much smaller than that of the flexible conductive biological material in the embodiment of the present invention. The content of the plasticizer (deep eutectic solvent) in the polymer material, on the one hand, more deep eutectic solvents will form hydrogen bonds with more molecules in the biopolymer chain, reducing the Intermolecular interaction, on the other hand, more deep eutectic solvents exist in biopolymers, which improves the softness of polymers, thereby achieving efficient plasticization of biopolymer materials and improving the mechanical properties of biopolymer materials, Reduce the tensile strength of biopolymer materials, improve the ductility of biopolymer materials, and then realize the preparation of flexible biopolymer materials. Compared with the prior art, this embodiment can realize the preparation of ultra-soft polymer materials. The tensile strength at break of the flexible conductive biopolymer material prepared in this embodiment is less than 10MPa, the modulus of elasticity is less than 500kPa, and the elongation rate is greater than 300 %. In addition, the ionic electrolyte contained in the deep eutectic solvent makes the flexible biopolymer material conductive, and finally realizes the preparation of flexible conductive biopolymer material.

In step S1, in one embodiment, the biopolymer is selected from one or more of cellulose, gelatin, chitosan, sodium alginate, carrageenan, agar, gum arabic, silk, and starch, But not limited to this.

In this embodiment, it is not limited to biopolymers, and the inventors found that polymers synthesized based on biopolymers and partially synthetic polymers are also suitable for the present invention. For example, the polymer synthesized based on biopolymers can be a cellulose derivative; the synthetic polymer can be one of polyvinylpyrrolidone, polyvinyl alcohol, and polyurethane, but not limited thereto.

In one embodiment, the mass content of the biopolymer in the biopolymer aqueous solution is 0.1%-30%. This mass content can fully dissolve the biopolymer to form a solution with a certain viscosity, which is beneficial to control the size and thickness of the film prepared in the subsequent molding process, reduces operational complexity, reduces equipment requirements, and is easy to operate.

The aqueous solution containing the deep eutectic solvent and the biopolymer obtained in step S2 is a uniform mixed solution.

In one embodiment, the deep eutectic solvent is prepared by mixing a first component and a second component, and the first component is selected from urea, glycerin, ethylene glycol, thiourea, gluconic acid, lemon acid, fructose, sorbitol, xylitol, and malic acid, and the second component is selected from one or both of amino acids and quaternary ammonium salts. In this embodiment, the first component is used as a hydrogen bond donor, and the second component is used as a hydrogen bond acceptor, and the deep eutectic solvent is prepared after the two are mixed at room temperature or under heating conditions.

In the prior art, single-component plasticizers (such as: single-component polyols, single-component glycerin, mannitol, etc.) are usually used, which have a general plasticizing effect on biopolymers, and the biopolymers obtained The elongation rate of the biopolymer material is less than 50%, and the hardness of the biopolymer material is relatively high. In this embodiment, the deep eutectic solvent is used as the plasticizer, and the deep eutectic solvent includes one or more hydrogen bond donors and one or more hydrogen bond donors. It is found by the inventor that it is different from the prior art Compared with plasticizers, deep eutectic solvents have better compatibility with biopolymers, and deep eutectic solvents have better compatibility with biopolymers, and are more suitable as plasticizers for biopolymers. As a plasticizer, the solvent exhibits a plasticizing effect completely different from that of the single-component plasticizers in the prior art. Using the deep eutectic solvent in this embodiment can make the elongation of the biopolymer material reach more than 300%. The minimum modulus of biopolymer materials can be as low as 10kPa.

In one embodiment, the mass content of the first component in the deep eutectic solvent is 25%-75%. This ratio enables the two components to form a good miscible solution, which in turn facilitates the interaction with the biopolymer.

In this embodiment, the mass content of the first component in the deep eutectic solvent is 25%-75%, that is to say, the mass content of the hydrogen bond donor in the deep eutectic solvent is 25%-75% %.

In one embodiment, the amino acid is selected from one or more of glycine, alanine, and proline.

In one embodiment, the quaternary ammonium salt is selected from one or both of betaine and choline chloride.

In one embodiment, the amino acid is selected from one or more of glycine, alanine, and proline, and the quaternary ammonium salt is selected from one or more of betaine and choline chloride .

In one embodiment, in the step of adding the deep eutectic solvent into the biopolymer aqueous solution, the quality of the deep eutectic solvent is the same as that between the deep eutectic solvent and the biopolymer aqueous solution. 20%-95% of the mass sum of biopolymers.

The proportion of the amount of deep eutectic solvent affects its plasticizing effect on biopolymers. Within a certain proportion, with the increase of the amount of deep eutectic solvent, the ductility of the prepared flexible conductive biopolymer material is improved. , modulus of elasticity reduces, when the quality of deep eutectic solvent is 20%-95% of the mass sum of biopolymer in described deep eutectic solvent and described biopolymer aqueous solution, deep eutectic solvent is to biopolymer The material has a pronounced softening effect.

In one embodiment, the deep eutectic solvent is added into the biopolymer aqueous solution, and the aqueous solution containing the deep eutectic solvent and the biopolymer is obtained after stirring for 0.5-6 hours.

In one embodiment, the step of adding the deep eutectic solvent into the aqueous biopolymer solution also includes adding one or more of electrolytes, surfactants, crosslinking agents, and conductive nanoparticles added to the biopolymer aqueous solution.

In this embodiment, the mechanical properties of the flexible conductive biopolymer material can be further improved by adding a crosslinking agent; the flexible conductive biopolymer material can also be improved by adding auxiliary agents including but not limited to electrolytes, surfactants, and conductive nanoparticles For example, adding electrolytes can improve the ionic conductivity of flexible conductive biopolymer materials; adding surfactants can improve the surface lubricity of flexible conductive biopolymer materials; adding conductive nanoparticles can form flexible electronically conductive composites. According to actual needs, one or more of cross-linking agent, electrolyte, surfactant, and conductive nanoparticles can be selected to improve the performance of the flexible conductive biopolymer material.

In one embodiment, the crosslinking agent is selected from one or more of glutaraldehyde and epoxy-terminated compounds, but is not limited thereto.

In one embodiment, the electrolyte is selected from one or more of sodium chloride, potassium chloride, and lithium chloride, but is not limited thereto.

In one embodiment, the surfactant is selected from one or more of Tween, Span, and phospholipids, but is not limited thereto.

In one embodiment, the conductive nanoparticles are selected from one or more of silver nanowires, silver nanosheets, carbon nanotubes, graphene, carbon black, liquid metal or other metal nanoparticles, but not limited to this.

In step S3, in one embodiment, the mechanical method includes one of molding, injection, extrusion, and calendering, but is not limited thereto.

In this embodiment, the aqueous solution containing a deep eutectic solvent and a biopolymer can be formed by one of mechanical methods including but not limited to molding, injection, extrusion, calendering, etc., and the water can be removed after drying to obtain the Flexible conductive biopolymer materials. The flexible conductive biopolymer material obtained after forming the aqueous solution containing deep eutectic solvent and biopolymer can be in any shape. In other words, the aqueous solution containing deep eutectic solvent and biopolymer can be molded according to actual needs to obtain Flexible conductive biopolymer materials of any shape required. For example, pour an aqueous solution containing a deep eutectic solvent and a biopolymer into a square mold to form and dry to obtain a film-like flexible conductive biopolymer material, and pour an aqueous solution containing a deep eutectic solvent and a biopolymer into a strip mold After molding and drying, a strip-shaped flexible conductive biopolymer material and the like are obtained.

In one embodiment, after the aqueous solution containing the deep eutectic solvent and the biopolymer is mechanically shaped, it is dried at a temperature lower than 100°C until the quality is constant, and the temperature can make the moisture Rapid removal without compromising biopolymer stability. The purpose of drying is to remove water from aqueous solutions containing deep eutectic solvents and biopolymers.

The embodiment of the present invention also provides a flexible conductive biopolymer material, which is prepared by the preparation method of the flexible conductive biopolymer material described in the embodiment of the present invention.

In one embodiment, the flexible conductive biopolymer material comprises a deep eutectic solvent and a biopolymer. Among them, the deep eutectic solvent accounts for 20%-95% of the mass of the flexible conductive biopolymer material.

In one embodiment, the flexible conductive biopolymer material further includes one or more of a cross-linking agent, an electrolyte, a surfactant, and conductive nanoparticles.

The flexible conductive biopolymer material in this embodiment belongs to a kind of ultrasoft polymer material, and its tensile strength at break is less than 10 MPa, elastic modulus is less than 500 kPa, and elongation is greater than 300%.

The flexible conductive biopolymer material in this embodiment has the ability to repair. For example, after the strip-shaped flexible biopolymer material breaks, the fracture can be repaired by heating. Heating methods include direct heating or putting in hot water. For example, lap the fractured samples together, then heat them to 60°C-80°C and keep them for 1-3 minutes to repair the fracture; or, immerse the fractured samples in hot water of 60°C-80°C for 30s to 1min, take them out and lap them together, and let them dry to repair the fracture.

The flexible conductive biopolymer material in this embodiment can be reused. The damaged flexible conductive biopolymer material can still form a mixed solution after being placed in hot water. After the mixed solution is molded and dried, a shape with a certain shape can be obtained again. Flexible conductive biopolymer materials. For example, add the damaged flexible conductive biopolymer material into water (water accounts for 30%-70% of the total mass of water and flexible conductive biopolymer material), heat to 60-90°C, stir for 30min, and then pour it into In the mold, the moisture is removed by drying, and the flexible conductive biopolymer material with a certain shape can be obtained again.

The flexible conductive biopolymer material in this embodiment has conductivity, because the deep eutectic solvent in the flexible conductive biopolymer material contains ionic electrolytes, so the flexible conductive biopolymer material has conductivity and can be used as an electrolyte or an electrical connection unit . The conductivity of the flexible conductive biopolymer material can also be further improved by adding electrolytes or conductive nanoparticles in the flexible conductive biopolymer material.

The embodiment of the present invention also provides an application of the flexible conductive biopolymer material described in the embodiment of the present invention in the preparation of flexible electronic devices.

In one embodiment, the flexible electronic device is a flexible bioelectronic device.

Below in conjunction with Figure 5, the raw materials, process, effect and application of the flexible conductive biopolymer material in the present invention are introduced as a whole. In the present invention, the natural raw material of biopolymer is mixed with solvent water in a certain proportion to obtain biopolymer solution, and then a plasticizer (deep eutectic solvent) containing two components is added to the biopolymer solution to obtain a mixed solution, and a flexible conductive biopolymer material (that is, the flexible material in the figure) is obtained after molding and drying ), and conductive materials can also be added according to actual needs to prepare flexible composite materials. The obtained flexible conductive biopolymer materials and flexible composite materials have flexible and stretchable properties and can be used in the fields of flexible electrodes and bioelectronics.

The present invention will be further described below by specific examples.

Example 1

Configuration gelatin mass fraction is the gelatin aqueous solution of 15%, 2.6g choline chloride and 3.4g glycerin are mixed, stir until completely uniform, then it is joined in the 13.3g gelatin aqueous solution (the quality of gelatin is the same as that of choline chloride and glycerin) The ratio of mass to weight is 1:3), after stirring for 2 hours to mix evenly, pour it into a film mold, and dry it for 24 hours at a temperature of 40°C and a humidity of 20% to obtain a flexible film material, which is designated as P1-1.

Repeat the above steps, the difference is that the quality of the gelatin aqueous solution is 20g, 30g, 40g, 60g, 120g respectively, that is, the ratio of the quality of the gelatin to the mass sum of choline chloride and glycerin is 1:2, 3:4, 1 :1, 3:2, 3:1, and the obtained flexible film materials are recorded as P1-2, P1-3, P1-4, P1-5, P1-6 respectively.

The flexible film material prepared in Example 1 was subjected to a stress-strain test, and the results are shown in FIG. 2 . It can be seen from Figure 2 that the elastic modulus of the flexible film material is less than 500kPa, and the elongation rate is greater than 300%. When the ratio of the mass of gelatin to the mass sum of choline chloride and glycerin is 1:3, that is, the flexible film material P1-1 has the highest ductility and the lowest elastic modulus.

The flexible film material prepared in Example 1 was subjected to a tensile test, and its tensile strength at break was less than 10 MPa.

Example 2

2.6g choline chloride and 3.4g glycerol were mixed, stirred until completely uniform, then it was added to 20g agar aqueous solution (the mass fraction of agar was 2%), after stirring for 2 hours and mixed uniformly, poured in the film mould, It was dried for 24 hours under the conditions of temperature 40° C. and humidity 20%, to obtain a flexible film material.

Repeat above-mentioned steps 4 times, difference is that agar aqueous solution (massfraction of agar is 2%) is replaced with carrageenan aqueous solution (massfraction of carrageenan is 2%), sodium alginate aqueous solution (massfraction of sodium alginate is 2%) respectively. 2%), an aqueous solution of chitosan (the mass fraction of chitosan is 2%), an aqueous solution of gum arabic (the mass fraction of gum arabic is 2%).

The flexible thin film material prepared in embodiment 2 is carried out stress-strain test, and the result is as shown in Figure 3, as can be seen from Figure 3, the elastic modulus of flexible thin film material is less than 500kPa, is made up of choline chloride and glycerin mixture The plasticizer has a good plasticizing effect on agar, carrageenan, sodium alginate, chitosan, and gum arabic.

Example 3

Prepare a gelatin aqueous solution with a gelatin mass fraction of 15%, mix 3.23g choline chloride and 2.77g urea, stir until completely uniform, then add it to 20g gelatin aqueous solution, stir for 2 hours and mix well, then pour it into a film mold , dried for 24 hours at a temperature of 40° C. and a humidity of 20%, to obtain a flexible film material, which is designated as P2.

Example 4

Configure the gelatin aqueous solution with a gelatin mass fraction of 15%, mix 3.19g choline chloride and 2.81g ethylene glycol, stir until completely mixed, then add it to 20g gelatin aqueous solution, stir for 2 hours and mix well, pour Put it into a film mold, and dry it for 24 hours at a temperature of 40° C. and a humidity of 20%, to obtain a flexible film material, which is designated as P3.

Example 5

Configure the gelatin aqueous solution with a gelatin mass fraction of 15%, mix 3g of choline chloride and 3g of sorbitol, stir until uniform, then add it to 20g of gelatin solution, stir for 2 hours and mix evenly, then pour into the film mold, Dry for 24 hours under the conditions of temperature 40° C. and humidity 20%, to obtain a flexible film material, denoted as P4.

The flexible film material P1-2 prepared in Example 1, the flexible film material P2 prepared in Example 3, the flexible film material P3 prepared in Example 4, and the flexible film material P4 prepared in Example 5 were subjected to a stress-strain test , the results are shown in Figure 4. It can be seen from Figure 4 that the elastic modulus of all flexible film materials is less than 500kPa, and the ductility of P2 is better than that of P1-2, and the ductility of P1-2 is better than that of P3. The ductility is better than P4.

Other tests:

Repair ability test: Cut the flexible film material P1-1 prepared in Example 1 into two sections, immerse in 80°C hot water for 30 seconds, take it out, splice the fractures together, and then dry them. The two sections of film materials can be intact spliced together, and has good ductility; the plasticized flexible film material P1-1 prepared in Example 1 was cut into two sections, and then the fractures were spliced together, and then the heating table was heated to 70°C, Keep it for 1 minute, and the two sections of film materials can be completely spliced together and have good ductility.

Recyclability test: Cut the flexible film material P1-1 prepared in Example 1 into pieces, add 3g of the pieces to 3g of water, heat to 80°C, stir for 30 minutes, pour it into a film mold, and heat it at 40°C After drying for 24 hours under the condition of ℃ and humidity of 20%, the flexible film material can still be obtained, which shows that the flexible material prepared in Example 1 is recyclable.

Conductivity test: After connecting the flexible film material P1-1 prepared in Example 1 into a circuit as an electrical connection wire, the LED bulb can work normally and still maintain a normal working state during the stretching process.

In summary, the present invention provides a flexible conductive biopolymer material and its preparation method and application. In the present invention, a deep eutectic solvent is added to the biopolymer solution as a plasticizer for the biopolymer, and the deep eutectic The solvent not only has a low melting point, but also contains a large number of hydrogen bonds that can interact with the hydrogen bonds of the biopolymer to form new hydrogen bonds, which breaks the hydrogen bonds in the biopolymer chain and reduces the molecular weight in the biopolymer chain. The interaction between them increases the mobility of biopolymer molecular chains; in addition, compared with plasticizers in the prior art (such as single-component glycerol, mannitol, etc.), deep eutectic solvents and The compatibility of biopolymers is better, and the content of deep eutectic solvent in the prepared flexible conductive biopolymer materials is as high as 95%, which further reduces the intermolecular interactions in the polymer chain, thereby realizing the biopolymer Efficient plasticization of materials, improving the mechanical properties of biopolymer materials, reducing the tensile strength of biopolymer materials, and improving the ductility of biopolymer materials. In addition, the deep eutectic solvent contains ionic electrolytes, making flexible conductive biopolymers The material has conductivity, and then realizes the preparation of flexible conductive biopolymer material. The flexible conductive biopolymer material prepared by the invention has repair ability, recyclability and conductive performance, and can be used to prepare flexible electronic devices.

It should be understood that the application of the present invention is not limited to the above examples, and those skilled in the art can make improvements or transformations according to the above descriptions, and all these improvements and transformations should belong to the protection scope of the appended claims of the present invention.

Claims

A method for preparing a flexible conductive biopolymer material, comprising the steps of:

Dissolving the biopolymer in water to obtain an aqueous biopolymer solution;

adding the deep eutectic solvent into the biopolymer aqueous solution, and stirring to obtain an aqueous solution containing the deep eutectic solvent and the biopolymer;

The aqueous solution containing the deep eutectic solvent and the biopolymer is mechanically shaped, and the flexible conductive biopolymer material is obtained after drying.
The preparation method of flexible conductive biopolymer material according to claim 1, wherein said biopolymer is selected from the group consisting of cellulose, gelatin, chitosan, sodium alginate, carrageenan, agar, gum arabic, silk , one or more of starch.
The method for preparing a flexible conductive biopolymer material according to claim 1, characterized in that the mass content of the biopolymer in the biopolymer aqueous solution is 0.1%-30%.
The method for preparing a flexible conductive biopolymer material according to claim 1, wherein the deep eutectic solvent is prepared by mixing a first component and a second component, and the first component is selected from urea , glycerol, ethylene glycol, thiourea, gluconic acid, citric acid, fructose, sorbitol, xylitol, malic acid, the second component is selected from amino acids, quaternary ammonium salts one or both.
The method for preparing a flexible conductive biopolymer material according to claim 4, wherein the mass content of the first component in the deep eutectic solvent is 25%-75%.
The preparation method of flexible conductive biopolymer material according to claim 4, is characterized in that, the amino acid is selected from one or more of glycine, alanine, proline, and/or, the quaternary The ammonium salt is selected from one or both of betaine and choline chloride.
The preparation method of flexible conductive biopolymer material according to claim 1, characterized in that, in the step of adding the deep eutectic solvent to the aqueous biopolymer solution, the quality of the deep eutectic solvent is 20%-95% of the mass sum of the biopolymer in the deep eutectic solvent and the biopolymer aqueous solution.
The method for preparing a flexible conductive biopolymer material according to claim 1, wherein the step of adding a deep eutectic solvent to the biopolymer aqueous solution also includes adding a crosslinking agent, an electrolyte, One or more of surfactants and conductive nanoparticles are added to the biopolymer aqueous solution.
A flexible conductive biopolymer material, characterized in that it is prepared by the method for preparing a flexible conductive biopolymer material according to any one of claims 1-8.
An application of the flexible conductive biopolymer material as claimed in claim 9 in the preparation of flexible electronic devices.