CN106943895B - A kind of the flexible bionic bilayer polymer film and preparation method and application of acetone stimuli responsive - Google Patents

Abstract

The invention discloses a kind of flexible bionic bilayer polymer film of acetone stimuli responsive and preparation method and application, which has double-layer structure flexible, wherein one layer is active layer, it is extremely strong to acetone stimulating responsive, with a thickness of 20~60 μm；Another layer be inert layer to the stimulation of acetone without response, with a thickness of 0.1~10 μm；Preparation method: with Kynoar (PVDF) and polyvinyl alcohol (PVA) for raw material, micro channel array is designed on silicon wafer by micro-processing technology, PVDF solution is uniformly laid in silicon template, it is dry under the conditions of 50~100 DEG C, oxygen plasma surface chemical modification 10 minutes, then PVA solution is uniformly laid on to PVDF monolayer surface, dry in 25~30 DEG C of environment and volatilized completely until solvent, bilayer film is removed from template；Obtained bilayer film is cut into thin-film device of different shapes, by the invertibity curling of absorption acetone steam initiation, bending, distortion, winds, circle round and rolls, realize the controllable deformation of flexible device.

Description

A flexible biomimetic double-layer polymer film responsive to acetone stimulation and preparation method thereof application

technical field

The invention relates to the technical field of biomimetic materials, in particular to a flexible biomimetic double-layer polymer film responsive to acetone stimulation, and a preparation method and application thereof.

Background technique

With the deepening of understanding and understanding of natural biological structures, the technology of simulating biological structures using physical and chemical synthesis techniques has gradually matured, which has greatly promoted the development of biomimetic materials. Devices developed through biomimetic materials have also been well used in industry, electronics, military and other fields. In particular, bionic soft materials will have even greater application value in the future, such as in the flexible electronics industry. A new type of intelligent flexible biomimetic material is prepared by simulating the derivation law of biological structure, which not only realizes the biomimetic performance from the structure, but also realizes the manipulation of the biomimetic behavior of the material through external stimuli, thus greatly expanding the application field of the material.

At present, most of the acetone-sensitive thin film materials are prepared from inorganic materials, such as: ZnFe ₂ O ₄ and LaFeO ₃ based thin films (Tianjin University, 2004); ZrO ₂ ZnO semiconductor materials based thin films (Journal of Sensing Technology, 1990 (3): 59-62); ZnO thin film (Electronic Components and Materials, 2007, 26(5): 46-48); SnO ₂ thin film (Sensor & ActuatorsB Chemical, 2006, 115(1): 460-464), etc. . Acetone-sensitive films prepared from inorganic materials tend to have poor flexibility and are not suitable for reuse, resulting in a narrow application range and shortened application life.

Recently, Yuan J et al. (Qiang Zhao, John W.C. Dunlop, XunlinQiu, Feihe Huang, Zibin Zhang, Jan Heyda, JoachimDzubiella, Markus Antonietti1 &JiayinYuan.Nature Communications, 5:4293,1-8) reported an organic polymer polymer The film has a uniform microporous structure and flexibility, and is highly sensitive to acetone. However, in addition to being sensitive to acetone, this film has strong sensitivity to other solvents such as tetrahydrofuran, piperidine, pyridine, etc., so the sensitivity and selectivity to acetone are not good. At the same time, the deformation process driven by acetone is not controllable. The technology needs to be further improved.

Theoretical analysis shows that in order to realize the high-efficiency and controllable biomimetic deformation performance of acetone-driven films, in addition to the precise design of the biomimetic structure of the film, the film must have very good tensile wear resistance, which can still be maintained after prolonged stimulation by acetone vapor. Ideal mechanical properties must have reversible stimuli-response behaviors, which are the basic elements for biomimetic materials to achieve biomimetic properties and the basic conditions for expanding their applications. Therefore, only by designing a reasonable bionic structure, in-depth understanding of the bionic mechanism, and optimizing the mechanical properties of materials, can the dynamic bionic process be controlled and the pace of application of materials be promoted.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an acetone stimulus-responsive flexible biomimetic double-layer polymer film that can be prepared in batches and realize industrialization, and a preparation method and application thereof.

The concrete technical scheme that realizes the object of the present invention is:

A flexible biomimetic double-layer polymer film responsive to acetone stimulation, characterized in that the film has a flexible double-layer structure, one of which is an active layer of a microchannel array structure, which is extremely responsive to acetone stimulation, and can be used at a temperature of 9KPa. Obvious deformation occurs in the acetone vapor pressure atmosphere, and the thickness is 20-60 μm; the other layer is an inert layer that has no response to the stimulation of acetone, and the thickness is 0.1-10 μm; wherein, the active layer is a PVDF layer; the inert layer is PVA Floor.

A preparation method of a flexible biomimetic double-layer polymer film responsive to acetone stimulation, the method comprises the following steps:

Step 1: Prepare a microchannel array on a silicon wafer by a micromachining method to obtain a silicon wafer template with microchannels; wherein, the microchannel array is a U-shaped microchannel array, and the channels of the microchannel array are parallel to each other, and the channels are parallel to each other. The width of the channel is 0.1 to 1.2 mm, the depth of the channel is 10 to 80 μm, the length of the channel is 30 to 70 mm, the spacing between adjacent channels is 0.1 to 1.6 mm, and the effective area of the overall channel on the silicon wafer is not less than 3600 mm ² ;

Step 2: Preparation of PVDF Solution for Active Layer

Put the solvent in the reaction vessel, under the condition of magnetic stirring, disperse the PVDF powder in the solvent, heat at 70～100℃ and keep stirring until a transparent solution is obtained; stop the heating and continue stirring for 1 after the temperature is cooled to room temperature. ~2 hours to remove air bubbles in the solution; finally, the obtained PVDF solution was sealed for use; wherein, the solvent was DMF, N-methylpyrrolidone (NMP) dimethylacetamide (DMAc), triethyl phosphate Ester (TEP) or dimethyl sulfoxide (DMSO); PVDF solution concentration is 0.1-0.5 g/mL;

Step 3: Preparation of the PVA solution for the inert layer

In the reaction vessel containing distilled water, add PVA solid, under magnetic stirring condition, heat at 50～90℃ for 10～15 hours, after cooling, let the cooling liquid stand still for 24 hours, take the saturated supernatant liquid in the reaction vessel and wait for use;

Step 4: Preparation of PVDF Monolayer

The silicon wafer template with microchannels obtained in step 1 was washed with acetone solvent, and dried under nitrogen atmosphere; the prepared PVDF solution was evenly spin-coated on the silicon wafer template by a glue dispenser, and the rotation speed of the glue dispenser was controlled At 50-100 rpm; move the silicon wafer template into a natural convection oven, and dry at 50-90 °C until the solvent volatilizes completely; the solvent volatilization triggers the self-assembly of PVDF polymer chain molecules, forming a spherical aggregated surface structure, and the obtained PVDF monolayer The film has a microchannel array, a uniform spherical structure, the diameter of the spherical particles is 5-15 μm, and the thickness of the PVDF single-layer film is 20-60 μm;

Step 5: Surface chemical modification of PVDF monolayer film

Oxygen plasma cleaner (Plasma Cleaner PDC-32G-2) was used to introduce a large number of hydroxyl groups on the surface of PVDF monolayer. Specific operation steps: open the chamber door of the oxygen plasma cleaning instrument, and place the silicon wafer template with PVDF film horizontally in the middle of the chamber; close the chamber door and the intake valve, and then vacuumize for 3 to 5 minutes; open the intake valve, Put in air, turn on the RF power switch, so that the oxygen shines on the surface of the PVDF film. After 10-20 minutes of irradiation, close the air inlet valve, RF power supply and vacuum pump in turn; then open the air inlet valve and let the air enter slowly until After the pressure in the chamber returned to atmospheric pressure, the chamber door was opened, and the treated PVDF monolayer film was taken out; at this time, the surface of the film changed from hydrophobicity to hydrophilicity, indicating that a large number of hydroxyl groups were introduced into the surface of the film. The role of the introduction of hydroxyl groups is to form strong hydrogen bonds with the hydroxyl groups in the inert layer structure to enhance the affinity between the bilayer membranes. The oxygen plasma cleaning surface of the PVDF monolayer is chemically modified, the gas used is air, and the relative humidity is 40-70%;

Step 6: Introduce an inert layer on the surface of the active layer PVDF film

The prepared PVA solution was evenly spin-coated on the surface of the chemically modified PVDF film by a spin coater, and the spin-coating speed was controlled at 50-100 rpm; after spin-coating for 5 min, the PVDF film silicon The sheet template was placed on a horizontal non-vibration table, dried at 25-30 °C for 24-48 hours, and the thickness after drying was 0.1-10 μm to obtain a PVDF/PVA bilayer film, that is, a flexible biomimetic bilayer film responsive to acetone stimulation. Molecular Films.

The inert layer PVA layer can be replaced by polyethylene glycol (PEG) layer, agarose (Agarose, water) layer, inulin layer, pectin layer or cellulose layer.

The application of the double-layer film obtained by the above method is to cut the obtained double-layer film into film devices of different shapes, and realize the flexible device by absorbing the reversible curling, bending, twisting, winding, turning and rolling caused by acetone vapor. Controllable deformation.

Compared with the prior art, the present invention has the following outstanding advantages:

The present invention is characterized in that it is different from the reported environment-sensitive materials, is based on low-cost polymers, designs a double-layer thin film through MEMS technology and chemical reaction, and introduces a micro-channel structure on the surface of the active layer to prepare superior mechanical properties and bionics. Deformation-controllable smart double-layer polymer film. The PVDF and PVA composite layers are closely combined, and the film has very good flexibility and maneuverability, and has a very high response performance to acetone vapor. Therefore, acetone-sensitive devices can be further designed and prepared.

The technical innovation of the present invention is mainly reflected in the complete use of macromolecular organic materials, and the preparation of a double-layer biomimetic film with a spherical particle structure of a micro-channel array through micromachining technology. The prepared film has super flexibility and mechanical strength, and is controllable to the sensitive deformation of acetone. Combining the methods of precision machining, micro-molding, surface chemical modification and the like, the invention can prepare practical acetone-sensitive biomimetic controllable deformation double-layer films in batches, and is suitable for industrialization.

Description of drawings

Fig. 1 is the scanning electron microscope (SEM) picture of the acetone-sensitive PVDF/PVA double-layer polymer film prepared in the embodiment of the present invention, showing the spherical granular structure on the PVDF surface;

2 is a picture of a PVDF/PVA double-layer film prepared by using a microchannel silicon wafer template according to the present invention, showing a fine channel array structure;

Fig. 3 is the deformation of the double-layer film driven by the acetone of the embodiment of the invention test, and the deformation law of the film can be adjusted by the cutting mode of the film; When cutting angle θ ₁ =90 °, the film absorbs acetone vapor and shows curling deformation; Cutting angle θ When ₁ = 60°, the film absorbs acetone vapor and shows a regular spiral tightening deformation; when the cutting angle θ ₁ = 30°, the film absorbs acetone vapor and shows a spiral tightening deformation, but the distance between two adjacent circles is larger. .

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

Example 1

Step 1: A silicon wafer template of a U-shaped microchannel array is prepared on a silicon wafer by micromachining techniques including oxidation, photolithography, and anisotropic wet etching; the channels of the microchannel array are parallel to each other, and the width of the channel is 0.4 mm, the depth of the channel is 20 μm, the length of the channel is 50 mm, the spacing between adjacent channels is 0.8 mm, and the effective area of the overall channel on the silicon wafer is not less than 3600 mm ² ;

Step 2: Preparation of PVDF Solution for Active Layer

Measure 100 mL of DMF (N,N-dimethylformamide) solvent into a 200 mL beaker, then under magnetic stirring, disperse 10 g PVDF powder in 100 mL DMF solvent; Stir continuously until a transparent solution is obtained; stop heating, and continue stirring for 1.5 hours after the temperature is cooled to room temperature to remove air bubbles in the solution; finally, the obtained PVDF solution is sealed for use; the concentration of PVDF solution is 0.1g/mL;

Step 3: Preparation of the PVA solution for the inert layer

10g of PVA solid was added to a 100 mL beaker filled with 50 mL of distilled water, and heated at 70°C for 12 hours under magnetic stirring. After cooling, the cooling liquid was kept at rest for 24 hours, and the supernatant saturated clear liquid in the beaker was taken for use;

Step 4: Preparation of PVDF Monolayer

The silicon wafer template with U-shaped microchannel array obtained in step 1 was washed with acetone solvent, and dried under nitrogen atmosphere; the prepared PVDF solution was evenly spin-coated on the silicon wafer template by a glue dispenser, and the glue dispenser The rotation speed was controlled at 90rpm; the silicon wafer template was moved into a natural convection oven, and dried at 50°C until the solvent evaporated completely; the solvent volatilization triggered the self-assembly of PVDF polymer chain molecules to form a spherical aggregated surface structure, and the obtained PVDF monolayer film It has a uniform spherical structure (shown in Figure 1), the diameter of spherical particles is 5 μm, and the thickness of PVDF single-layer film is 40 μm;

Step 5: Surface chemical modification of PVDF monolayer film

Oxygen plasma cleaner (Plasma Cleaner PDC-32G-2) was used to introduce a large number of hydroxyl groups on the surface of PVDF monolayer. Specific operation steps: open the chamber door of the oxygen plasma cleaning instrument, and place the silicon wafer template with PVDF film in the middle of the chamber horizontally; close the chamber door and the intake valve, and then vacuum for 3 minutes; open the intake valve, Put in air, turn on the RF power switch, so that the oxygen shines on the surface of the PVDF film. After 10 minutes of irradiation, close the air inlet valve, RF power supply and vacuum pump in turn; then open the air inlet valve and let the air slowly enter until the cavity. After the pressure returned to atmospheric pressure, the chamber door was opened, and the silicon wafer template of the PVDF monolayer film after treatment was taken out; at this time, the surface of the film changed from hydrophobicity to hydrophilicity, indicating that a large number of hydroxyl groups were introduced into the surface of the film. The role of the introduction of hydroxyl groups is to form strong hydrogen bonds with the hydroxyl groups in the inert layer structure to enhance the affinity between the bilayer membranes. The gas used for chemical modification is air with a relative humidity of 50%.

Step 6: Introduce an inert layer on the surface of the active layer PVDF film

The prepared PVA solution was evenly spin-coated on the surface of the chemically modified PVDF film by a spin coater, and the spin-coating speed was controlled at 80 rpm; after spin-coating for 5 min, the silicon wafer of the PVDF film was evenly covered by the PVA solution. The template was placed on a horizontal non-vibration table, and dried at 30 °C for 48 hours. After drying, the thickness of the PVA film was 5 μm, and the PVDF/PVA bilayer film, that is, a flexible biomimetic bilayer polymer film responsive to acetone stimulation, was prepared (Fig. 2). shown).

Application of the film prepared by the invention: extracting the PVDF/PVA double-layer film from the template, and cutting it into a flexible biomimetic double-layer film device of a specific shape for application testing. The bilayer film prepared in this example can exhibit reversible mechanical deformation properties of curling, bending, twisting, winding, convolution and rolling under the driving of acetone vapor (shown in Figure 3).

Example 2

Step 1: A silicon wafer template of a U-shaped microchannel array is prepared on a silicon wafer by micromachining techniques including oxidation, photolithography, and anisotropic wet etching; the channels of the microchannel array are parallel to each other, and the width of the channel is 0.6 mm, the depth of the channel is 30 μm, the length of the channel is 50 mm, the spacing between adjacent channels is 0.8 mm, and the effective area of the overall channel on the silicon wafer is not less than 3600 mm ² ;

Step 2: Preparation of PVDF Solution for Active Layer

Measure 100 mL of NMP (N-methylpyrrolidone) solvent into a 200 mL beaker, and then under magnetic stirring, disperse 20 g PVDF powder in 100 mL of NMP solvent; heat at 70 °C and keep stirring until the obtained Transparent solution; stop heating, and continue stirring for 1.5 hours after the temperature is cooled to room temperature to remove air bubbles in the solution; finally, the obtained PVDF solution is sealed for use; the concentration of PVDF solution is 0.2g/mL;

Step 3: Prepare the solution for the inert layer

In a reaction vessel filled with 100 mL of distilled water, add 5 g of solid agarose, and under magnetic stirring, heat at 90 °C until the agarose is completely dissolved to prepare an aqueous solution of agarose; The prepared agarose solution was sealed for use; the concentration of the agarose solution was 0.05g/mL;

Step 4: Preparation of PVDF Monolayer

The silicon wafer template with U-shaped microchannel array obtained in step 1 was washed with acetone solvent, and dried under nitrogen atmosphere; the prepared PVDF solution was evenly spin-coated on the silicon wafer template by a glue dispenser, and the glue dispenser The rotation speed was controlled at 90rpm; the silicon wafer template was moved into a natural convection oven, and dried at 70°C until the solvent evaporated completely; the solvent volatilization triggered the self-assembly of PVDF polymer chain molecules to form a spherical aggregated surface structure, and the obtained PVDF monolayer film It has a uniform spherical structure, the diameter of spherical particles is 8 μm, and the thickness of PVDF single-layer film is 50 μm;

Step 5: Surface chemical modification of PVDF monolayer film

Oxygen plasma cleaner (Plasma Cleaner PDC-32G-2) was used to introduce a large number of hydroxyl groups on the surface of PVDF monolayer. Specific operation steps: open the chamber door of the oxygen plasma cleaning instrument, and place the silicon wafer template with PVDF film in the middle of the chamber horizontally; close the chamber door and the intake valve, and then vacuum for 3 minutes; open the intake valve, Put in air, turn on the RF power switch, so that the oxygen shines on the surface of the PVDF film. After 10 minutes of irradiation, close the air inlet valve, RF power supply and vacuum pump in turn; then open the air inlet valve and let the air slowly enter until the cavity. After the pressure returned to atmospheric pressure, the chamber door was opened, and the silicon wafer template of the PVDF monolayer film after treatment was taken out; at this time, the surface of the film changed from hydrophobicity to hydrophilicity, indicating that a large number of hydroxyl groups were introduced into the surface of the film. The role of the introduction of hydroxyl groups is to form strong hydrogen bonds with the hydroxyl groups in the inert layer structure to enhance the affinity between the bilayer membranes. The gas used for chemical modification is air with a relative humidity of 50%.

Step 6: Introduce an inert layer on the surface of the active layer PVDF film

The prepared agarose solution was evenly spin-coated on the surface of the chemically modified PVDF film by a spinner, and the spin-coating speed was controlled at 80 rpm; The silicon wafer template was placed on a horizontal non-vibration table, and dried at 30 °C for 48 hours. After drying, the thickness of the agarose film was 10 μm, and the PVDF/agarose bilayer film, that is, a flexible biomimetic bilayer polymer responsive to acetone stimulation, was prepared. film.

Application of the film prepared by the invention: extracting the PVDF/agarose bilayer film from the template, and cutting it into a flexible biomimetic bilayer film device of a specific shape for application testing. The bilayer film prepared in this example can exhibit reversible mechanical deformation properties of curling, bending, twisting, winding, convolution and rolling under the driving of acetone vapor.

Example 3

Step 1: A silicon wafer template of a U-shaped microchannel array is prepared on a silicon wafer by micromachining techniques including oxidation, photolithography, and anisotropic wet etching; the channels of the microchannel array are parallel to each other, and the width of the channel is 0.8 mm, the depth of the channel is 40 μm, the length of the channel is 50 mm, the spacing between adjacent channels is 0.8 mm, and the effective area of the overall channel on the silicon wafer is not less than 3600 mm ² ;

Step 2: Preparation of PVDF Solution for Active Layer

Measure 100 mL of DMSO (dimethyl sulfoxide) solvent into a 200 mL beaker, then under magnetic stirring, disperse 20 g PVDF powder in 100 mL of DMSO solvent; heat at 70 °C and keep stirring until transparent solution; stop heating, and continue stirring for 1.5 hours after the temperature is cooled to room temperature to remove air bubbles in the solution; finally, the obtained PVDF solution is sealed for use; the concentration of PVDF solution is 0.2g/mL;

Step 3: Prepare the solution for the inert layer

In a reaction vessel filled with 100 mL of distilled water, add 20 g of polyethylene glycol solid, and under magnetic stirring, heat at 50 °C until the polyethylene glycol is completely dissolved to prepare an aqueous polyethylene glycol solution; after cooling, the cooling The solution was kept at rest for 24 hours, and finally the obtained polyethylene glycol solution was closed for use; the concentration of the polyethylene glycol solution was 0.2 g/mL;

Step 4: Preparation of PVDF Monolayer

The silicon wafer template with U-shaped microchannel array obtained in step 1 was washed with acetone solvent, and dried under nitrogen atmosphere; the prepared PVDF solution was evenly spin-coated on the silicon wafer template by a glue dispenser, and the glue dispenser The rotation speed was controlled at 90rpm; the silicon wafer template was moved into a natural convection oven, and dried at 90°C until the solvent evaporated completely; the solvent volatilization triggered the self-assembly of PVDF polymer chain molecules to form a spherical aggregated surface structure, and the obtained PVDF monolayer film It has a uniform spherical structure, the diameter of spherical particles is 15 μm, and the thickness of PVDF single-layer film is 60 μm;

Step 5: Surface chemical modification of PVDF monolayer film

Oxygen plasma cleaner (Plasma Cleaner PDC-32G-2) was used to introduce a large number of hydroxyl groups on the surface of PVDF monolayer. Specific operation steps: open the chamber door of the oxygen plasma cleaner, and place the silicon wafer template with PVDF film in the middle of the chamber horizontally; close the chamber door and the intake valve, and then vacuum for 3 minutes; open the intake valve, Put in air, turn on the RF power switch, so that the oxygen shines on the surface of the PVDF film. After 10 minutes of irradiation, close the air inlet valve, RF power supply and vacuum pump in turn; then open the air inlet valve and let the air slowly enter until the cavity. After the pressure returned to atmospheric pressure, the chamber door was opened, and the silicon wafer template of the PVDF monolayer film after treatment was taken out; at this time, the surface of the film changed from hydrophobicity to hydrophilicity, indicating that a large number of hydroxyl groups were introduced into the surface of the film. The role of the introduction of hydroxyl groups is to form strong hydrogen bonds with the hydroxyl groups in the inert layer structure to enhance the affinity between the bilayer membranes. The gas used for chemical modification is air with a relative humidity of 50%.

Step 6: Introduce an inert layer on the surface of the active layer PVDF film

The prepared polyethylene glycol solution was evenly spin-coated on the surface of the chemically modified PVDF film by a spin coater, and the spin coating speed was controlled at 80 rpm; after spin coating for 5 min, the polyethylene glycol solution was evenly covered The silicon wafer template of the PVDF film was placed on a horizontal non-vibration table, and dried at 30 °C for 48 hours. After drying, the thickness of the polyethylene glycol film was 12 μm, and the PVDF/polyethylene glycol bilayer film was prepared. Responsive flexible biomimetic bilayer polymeric films.

Application of the film prepared by the invention: extracting the PVDF/polyethylene glycol double-layer film from the template, and cutting it into a flexible biomimetic double-layer film device of a specific shape for application testing. The bilayer film prepared in this example can exhibit reversible mechanical deformation properties of curling, bending, twisting, winding, convolution and rolling under the driving of acetone vapor.

Claims (4)

1. a kind of flexible bionic bilayer polymer film of acetone stimuli responsive, which is characterized in that the film has flexible double Layer structure can steam wherein one layer of active layer for micro channel array structure, strong to acetone stimulating responsive in the acetone of 9KPa Apparent deformation is generated in vapour pressure atmosphere, with a thickness of 20~60 μm；Another layer is for inert layer to the stimulation of acetone without response, thickness Degree is 0.1~10 μm；Wherein, the active layer is PVDF layers；Inert layer is PVA layers.

2. a kind of preparation method of the flexible bionic bilayer polymer film of acetone stimuli responsive, which is characterized in that this method packet Include following steps:

Step 1: micro channel array being prepared on silicon wafer by micro-processing method, obtains the silicon wafer template with microchannel；Its In, the micro channel array is U-shaped micro channel array, and each channel of micro channel array is parallel to each other, and the width in channel is 0.1 ~1.2 mm, the depth in channel are 10~80 μm, 30~70 mm of passage length, and adjacency channel spacing is 0.1~1.6 mm, silicon The effective area of on piece integral passage is not less than 3600 mm²；

Step 2: preparing the PVDF solution of active layer

Solvent is placed in reaction vessel, under the conditions of magnetic agitation, is dispersed PVDF powder in solvent, at 70~100 DEG C Lower heating is simultaneously stirred continuously until obtaining clear solution；Stop heating, after temperature is cooled to room temperature, it is small to continue stirring 1~2 When, to remove the bubble in solution；Finally PVDF solution obtained is closed stand-by；Wherein, the solvent is DMF, N- methyl Pyrrolidones (NMP) dimethyl acetamide (DMAc), triethyl phosphate (TEP) or dimethyl sulfoxide (DMSO)；PVDF solution Concentration is 0.1~0.5 g/mL；

Step 3: preparing the PVA solution of inert layer

In the reaction vessel equipped with distilled water, PVA solid is added, under the conditions of magnetic agitation, 50~90 DEG C of heating 10~15 Hour, after cooling, by coolant liquid static 24 hours, take the upper layer in reaction vessel to be saturated clear liquid stand-by；

Step 4: preparation PVDF monofilm

The silicon wafer template with microchannel obtained with acetone solvent cleaning step 1, and dry in a nitrogen atmosphere；Utilize spin coating PVDF solution obtained is uniformly spun in silicon wafer template by machine, and sol evenning machine rotation speed is controlled in 50~100 rpm；It will Silicon wafer template moves into free convection baking oven, is dried at 50~90 DEG C until solvent volatilization is complete；It is poly- that solvent volatilization causes PVDF Close the self assembly of object chain molecule, form the surface texture of conglobulation, obtained PVDF single thin film have micro channel array, Even chondritic, spherical particle diameter are 5~15 μm, and PVDF monolayer film thickness is 20~60 μm；

Step 5:PVDF single thin film surface chemical modification

Oxygen plasma cleaning device chamber door is opened, the silicon wafer template level for being formed with PVDF single thin film is put into the interposition of cavity It sets；Chamber door and intake valve are closed, is then vacuumized 3~5 minutes；Intake valve is opened, air is put into, opens radio-frequency power supply switch, Oxygen radiance is set to be irradiated to PVDF thin film surface, irradiation 10~after twenty minutes, successively close intake valve, radio-frequency power supply and vacuum Pump；Then intake valve is opened again, air is allowed slowly to enter, and after pressure is restored to atmospheric pressure in cavity, is opened chamber door, is taken out PVDF single thin film silicon wafer template that treated；Gases used PVDF single thin film surface chemical modification is air, relative humidity 40~70%；

Step 6: introducing inert layer on active layer PVDF thin film surface

The PVA solution prepared is uniformly spun on the PVDF thin film surface after surface chemical modification, spin coating using sol evenning machine Speed control is in 50~100 rpm；After 5 min of spin coating, the PVDF thin film silicon wafer template of PVA solution uniform fold is placed in water It puts down on vibrationless table top, it is 24~48 hours dry in 25~30 DEG C of environment, with a thickness of 0.1~10 μm after drying, it is made PVDF/PVA bilayer film, that is, acetone stimuli responsive flexible bionic bilayer polymer film.

3. preparation method according to claim 2, which is characterized in that described inert layer PVA layers can use polyethylene glycol Layer, agarose layer, inulin layer, pectin layer or cellulose layer substitution.

4. a kind of application of bilayer film made from claim 2, which is characterized in that bilayer film obtained is cut into difference The thin-film device of shape by the invertibity curling of absorption acetone steam initiation, bending, distortion, winds, circles round and rolls, real The controllable deformation of existing flexible device.