Nano composite hydrogel and preparation method thereof

Abstract

The preparation method comprises the following steps: carrying out surface modification and uniform dispersion treatment on aramid fibers to prepare an aramid nanofiber dispersion liquid; adding the aramid nanofiber dispersion liquid into the polyacrylamide prepolymerization solution, and uniformly stirring to obtain a mixed solution; and carrying out in-situ polymerization treatment on the mixed solution to obtain the nano-composite hydrogel, adding metal salt to endow the hydrogel with ionic conductivity, and enabling the hydrogel to have stable electrical properties by virtue of an ionic conductivity mechanism. Benefited from the strong interface bonding effect between the aramid nanofiber and the polyacrylamide matrix, the hydrogel shows excellent mechanical properties, and has both flexibility and elasticity. In addition, due to the sensitive electric response characteristic and high stability, the material can serve as a substrate material of wearable equipment, the human body movement and rehabilitation state is monitored in real time, and the wide application prospect is achieved in the field of flexible electronics.

Description

Technical Field

[0001] This invention belongs to the field of natural polymer materials technology, and specifically relates to a nanocomposite hydrogel and its preparation method. Background Technology

[0002] Polymer hydrogels are soft, wet materials formed by a three-dimensional cross-linked network of polymers and deionized water. They have strong water absorption and retention capabilities, can recover their original shape, and are similar to biological tissues, making them promising for applications in tissue engineering and regenerative medicine.

[0003] High water content can improve the ion mobility of ion-conductive hydrogels, but it will significantly reduce their mechanical properties. Furthermore, existing gels suffer from insufficient strength, poor toughness, and poor fatigue resistance.

[0004] Existing technologies cannot simultaneously meet the high water content requirements and good mechanical properties of ion-conducting hydrogels. They are unable to meet the requirements for improved ion mobility, and their insufficient strength, toughness, and fatigue resistance severely limit their practical applications and make them unsuitable for use in tissue engineering and regenerative medicine. Summary of the Invention

[0005] The purpose of this invention is to provide a nanocomposite hydrogel and its preparation method to solve the problems of insufficient strength, toughness and poor fatigue resistance of existing gels.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for preparing a nanocomposite hydrogel, comprising: Aramid fibers were surface modified and uniformly dispersed to obtain an aramid nanofiber dispersion. Aramid nanofiber dispersion was added to polyacrylamide prepolymer solution and stirred until homogeneous to obtain a mixed solution; The mixed solution was subjected to in-situ polymerization to obtain a nanocomposite hydrogel.

[0007] Furthermore, the surface modification and uniform dispersion treatment of the aramid fibers to obtain an aramid nanofiber dispersion includes: Aramid fibers and potassium hydroxide were added to dimethyl sulfoxide and stirred at room temperature for one week to obtain an aramid solution; A measured amount of aramid solution was added to allyl chloride, and the mixture was stirred at a constant temperature to obtain a modified aramid solution. Dimethyl sulfoxide was added to the modified aramid solution to dilute it to a mass concentration of 0.01 wt%. Then, while mechanically stirring, a 1:1 mass ratio of dimethyl sulfoxide / water mixture was added dropwise until the solution became clear, thus obtaining a mixed solution. The mixed solution was poured into a vacuum filtration device for filtration. The solid on the filter membrane was removed and deionized water was added. The solution was then ultrasonically vibrated using an ultrasonic cell disruptor to obtain an aramid nanofiber dispersion.

[0008] Furthermore, when the modified aramid solution was obtained, it was stirred at a constant temperature of 30°C for 24 hours; the dimethyl sulfoxide / water mixture with a mass ratio of 1:1 was added dropwise at a rate of 1 mL / h.

[0009] Furthermore, the amount of aramid fiber used is 0.2%-1.2% of the mass of the nanocomposite.

[0010] Furthermore, the mass ratio of aramid fiber, potassium hydroxide, and dimethyl sulfoxide is 1:1.5:99.

[0011] Furthermore, the molar ratio of chloropropylene to aramid fiber is 1:20.

[0012] Furthermore, the aramid nanofiber dispersion is added to the polyacrylamide prepolymer solution and stirred evenly to obtain a mixed solution. The polyacrylamide prepolymer solution includes acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate, and ammonium persulfate, and the mass ratio of acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate, and ammonium persulfate is 2:0.002:(0.1~2):0.1:0.08.

[0013] Furthermore, the in-situ polymerization treatment involved setting the oven temperature to 60°C and letting it stand for 1 hour.

[0014] Secondly, the present invention provides a nanocomposite hydrogel, which is prepared based on the aforementioned method for preparing a nanocomposite hydrogel.

[0015] Thirdly, the present invention provides an application of a nanocomposite hydrogel for flexible electronic devices.

[0016] Compared with the prior art, the present invention has the following technical effects: This invention provides a method for preparing a nanocomposite hydrogel. The method involves adding a surface-modified aramid nanofiber dispersion to a polyacrylamide prepolymer solution and stirring until a homogeneous mixture is obtained. The prepolymer solution includes acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate, and ammonium persulfate. The mixture is then subjected to in-situ polymerization to obtain the nanocomposite hydrogel. The addition of a metal salt imparts ionic conductivity to the hydrogel, and this ionic conductivity mechanism gives the hydrogel stable electrical properties. Thanks to the strong interfacial bonding between the aramid nanofibers and the polyacrylamide matrix, this hydrogel exhibits excellent mechanical properties while maintaining flexibility and elasticity. Furthermore, its sensitive electrical response characteristics and high stability make it suitable as a substrate material for wearable devices, enabling real-time monitoring of human movement and rehabilitation status, and it has broad application prospects in the field of flexible electronics.

[0017] This invention alters the mechanical properties of hydrogels by changing the concentration of aramid nanofibers. Compared to previous methods for improving the response rate of nanocomposite hydrogels, this method eliminates the need for any additional components or post-processing, further simplifying the preparation process and making the reaction simple and controllable. The prepared hydrogels also exhibit rapid response and high, controllable mechanical properties. Furthermore, the mechanical properties of the hydrogel can be adjusted by changing the content of aramid nanofibers to meet the needs of different applications.

[0018] The nanocomposite hydrogel prepared by this invention has good mechanical strength, flexibility and conductivity through the synergistic effect of hydrogen bonding, covalent bonding and electrostatic interaction. Attached Figure Description

[0019] Figure 1 The tensile stress-strain curves of the nanocomposite hydrogels provided in Examples 1-4 of this invention are shown.

[0020] Figure 2 The impedance diagrams of the nanocomposite hydrogels provided in Examples 5-9 of this invention are shown.

[0021] Figure 3 The infrared spectra of the nanocomposite hydrogel and monomers provided in the embodiments of the present invention are shown. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] Example 1: This invention provides a method for preparing a nanocomposite hydrogel, comprising: Aramid fibers were surface modified and uniformly dispersed to obtain an aramid nanofiber dispersion. Aramid nanofiber dispersion was added to polyacrylamide prepolymer solution and stirred until homogeneous to obtain a mixed solution; The mixed solution was subjected to in-situ polymerization to obtain a nanocomposite hydrogel.

[0025] This invention utilizes aramid fibers, which possess high strength, high modulus, and good dimensional stability, as nanofillers. These fibers form a double-crosslinked structure within a polyacrylamide hydrogel network through covalent and hydrogen bonds. This structure enhances the hydrogel's tensile strength, fracture toughness, and fatigue resistance, while also providing excellent structural stability through its three-dimensional network framework. Furthermore, to ensure the prepared composite hydrogel exhibits both flexibility at high water content and ionic conductivity, a high-strength, low-hysteresis nanocomposite hydrogel has been developed.

[0026] Example 2: This invention provides a method for preparing a nanocomposite hydrogel, comprising: S1, aramid fibers are surface modified and uniformly dispersed to obtain an aramid nanofiber dispersion; S2, the dispersion is added to the polyacrylamide prepolymer solution and stirred until homogeneous to obtain a mixed solution; The polyacrylamide prepolymer solution includes acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate, and ammonium persulfate; S3, the mixed solution is subjected to in-situ polymerization treatment to obtain nanocomposite hydrogel.

[0027] Step S1 specifically includes the following steps: 1.1) Add aramid fiber and potassium hydroxide to dimethyl sulfoxide and stir for one week at room temperature to obtain an aramid solution; 1.2) Take a quantitative amount of the aramid solution and add allyl chloride, and stir at 30°C for 24 hours to obtain the modified aramid solution; 1.3) Dimethyl sulfoxide was added to the modified aramid solution to dilute it to a mass concentration of 0.01 wt%. Then, while mechanically stirring, a 1:1 mass ratio of dimethyl sulfoxide / water mixture was added dropwise at a rate of 1 mL / h until the solution became clear and a mixed solution was obtained. 1.4) Pour the mixed solution into a vacuum filtration device for filtration, remove the solid on the filter membrane, add 10g of deionized water, and use an ultrasonic cell disruptor to ultrasonically vibrate to obtain an aramid nanofiber dispersion.

[0028] The amount of aramid fiber used is 0.2%-1.2% of the mass of the nanocomposite.

[0029] The mass ratio of the aramid fiber, potassium hydroxide, and dimethyl sulfoxide is 1:1.5:99.

[0030] The molar ratio of allyl chloride to aramid fiber is 1:20.

[0031] The acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate, and ammonium persulfate are in a mass ratio of 2:0.002:(0.1~2):0.1:0.08.

[0032] The in-situ polymerization treatment involves setting the oven temperature to 60°C and letting it stand for 1 hour.

[0033] The nanocomposite hydrogel prepared according to the above method has a water content of 52%–64% and a resistivity of 0.6–4.8 S / m.

[0034] Example 3: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 2g of the reaction solution and add 0.007ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 6g of dimethyl sulfoxide to the modified aramid solution, and then add 100g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.25g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) Pour the reaction mixture into a dumbbell-shaped polytetrafluoroethylene mold with a length × width × thickness of 50 × 8.5 × 2 mm, and place it in a 60°C oven to cure for 1 h to obtain a nanocomposite hydrogel sample containing 1%.

[0035] Example 4: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 4g of the reaction solution and add 0.014ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 14 g of dimethyl sulfoxide to the modified aramid solution, and then add 200 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.25g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) Pour the reaction mixture into a dumbbell-shaped polytetrafluoroethylene mold with dimensions of 50×8.5×2mm (length×width×thickness), and place it in a 60℃ oven to cure for 1 hour to obtain a nanocomposite hydrogel sample containing 2%.

[0036] Example 5: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 8g of the reaction solution and add 0.028ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 24 g of dimethyl sulfoxide to the modified aramid solution, and then add 400 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.25g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) Pour the reaction mixture into a dumbbell-shaped polytetrafluoroethylene mold with dimensions of 50×8.5×2mm (length×width×thickness), and place it in a 60℃ oven to cure for 1 hour to obtain a nanocomposite hydrogel sample containing 4%.

[0037] Example 6: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 12g of the reaction solution and add 0.042ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 36g of dimethyl sulfoxide to the modified aramid solution, and then add 600g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.25g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) Pour the reaction mixture into a dumbbell-shaped polytetrafluoroethylene mold with dimensions of 50×8.5×2mm (length×width×thickness), and place it in a 60℃ oven to cure for 1 hour to obtain a nanocomposite hydrogel sample containing 6%.

[0038] Comparative example: (a) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.25g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in 10g deionized water, and stir at 25℃ for 24h to obtain a polyacrylamide prepolymer solution. (b) The prepolymer solution was poured into a dumbbell-shaped polytetrafluoroethylene mold with a length × width × thickness of 50 × 8.5 × 2 mm, and then placed in a 60°C oven to cure for 1 h to obtain an acrylamide-based conductive hydrogel sample.

[0039] The gel strips prepared in Examples 3-6 and the comparative example were subjected to tensile property tests in a universal testing machine at a tensile speed of 20 mm / min. After the tests, the corresponding tensile load-displacement data were exported and converted into tensile stress-strain curves using a formula. The formula for converting displacement data into tensile strain data in the tensile test is as follows: Where ε t Represents tensile strain. This represents the displacement during spline stretching. This represents the length of the spline in its initial tensile state. The formula for converting tensile load into tensile stress data is: , Where represents tensile stress. Represents tensile load. This represents the cross-sectional area of ​​the spline (width × thickness). Specific test results are as follows: Figure 1 As shown, the tensile stress of the gel increases to varying degrees with the increase of aramid nanofiber content, indicating that the gel has excellent tensile properties and that the mechanical properties of the hydrogel can be adjusted by changing the content of aramid nanofiber.

[0040] Example 7: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 8g of the reaction solution and add 0.028ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 24 g of dimethyl sulfoxide to the modified aramid solution, and then add 400 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.1g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) The reaction mixture was poured into a rectangular polytetrafluoroethylene mold with a length × width × thickness of 30 × 10 × 2 mm and placed in an oven at 60 °C for 1 h to obtain a nanocomposite hydrogel sample containing 0.1 M NaCl.

[0041] Example 8: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 8g of the reaction solution and add 0.028ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 24 g of dimethyl sulfoxide to the modified aramid solution, and then add 400 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.25g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) The reaction mixture was poured into a rectangular polytetrafluoroethylene mold with dimensions of 30×10×2mm and placed in an oven at 60℃ for 1 hour to obtain a nanocomposite hydrogel sample containing 0.25M NaCl.

[0042] Example 9: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 8g of the reaction solution and add 0.028ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 24 g of dimethyl sulfoxide to the modified aramid solution, and then add 400 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 0.5g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) The reaction mixture was poured into a rectangular polytetrafluoroethylene mold with a length × width × thickness of 30 × 10 × 2 mm and placed in a 60 ° C oven to cure for 1 h to obtain a nanocomposite hydrogel sample containing 0.5 M NaCl.

[0043] Example 10: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 8g of the reaction solution and add 0.028ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 24 g of dimethyl sulfoxide to the modified aramid solution, and then add 400 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 1g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) The reaction mixture was poured into a rectangular polytetrafluoroethylene mold with a length × width × thickness of 30 × 10 × 2 mm and placed in a 60 ° C oven to cure for 1 h to obtain a nanocomposite hydrogel sample containing 1 M NaCl.

[0044] Example 11: (a) Take 1g of aramid fiber and 1.5g of potassium hydroxide and dissolve them in 99g of dimethyl sulfoxide. Stir at room temperature for one week. Take 8g of the reaction solution and add 0.028ml of allyl chloride. Stir at 30℃ for 24h to obtain the modified aramid solution. (b) Add 24 g of dimethyl sulfoxide to the modified aramid solution, and then add 400 g of dimethyl sulfoxide / water mixture with a mass ratio of 1:1 dropwise while mechanically stirring. The dropping rate is set to 1 mL / h to obtain a mixed solution. (c) The mixed solution is poured into a vacuum filtration device for filtration, the solid on the filter membrane is removed and 10g of deionized water is added, and the aramid nanofiber dispersion is obtained by ultrasonic vibration using an ultrasonic cell disruptor. (d) Take 2g acrylamide, 0.002g N,N-methylenebisacrylamide, 2g sodium chloride, 0.1g sodium alginate and 0.08g ammonium persulfate, dissolve them in aramid nanofiber dispersion, and stir at 25℃ for 24h; (e) The reaction mixture was poured into a rectangular polytetrafluoroethylene mold with a length × width × thickness of 30 × 10 × 2 mm and placed in a 60 ° C oven to cure for 1 h to obtain a nanocomposite hydrogel sample containing 2 M NaCl.

[0045] The hydrogel strips prepared in Examples 7-11 were subjected to impedance testing on an electrochemical workstation, and the corresponding data were exported after the tests. The conductivity was then calculated using the L / (R×S) equation, where L is the sample thickness, S represents the sample cross-sectional area (i.e., the product of width and thickness), and R represents the resistance of the sample. Specific test results are as follows: Figure 2 As shown in the figure, the conductivity of the gel increases with the increase of sodium chloride content.

[0046] Example 12: The present invention provides a nanocomposite hydrogel, which is prepared based on the preparation method of the nanocomposite hydrogel described above.

[0047] Example 13: This invention provides an application of a nanocomposite hydrogel for flexible electronic devices.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a nanocomposite hydrogel, characterized in that, include: Aramid fibers were surface modified and uniformly dispersed to obtain an aramid nanofiber dispersion. Aramid nanofiber dispersion was added to polyacrylamide prepolymer solution and stirred until homogeneous to obtain a mixed solution; The mixed solution was subjected to in-situ polymerization to obtain a nanocomposite hydrogel.

2. The method for preparing a nanocomposite hydrogel according to claim 1, characterized in that, The surface modification and uniform dispersion treatment of aramid fibers to obtain an aramid nanofiber dispersion includes: Aramid fibers and potassium hydroxide were added to dimethyl sulfoxide and stirred at room temperature for one week to obtain an aramid solution; A measured amount of aramid solution was added to allyl chloride, and the mixture was stirred at a constant temperature to obtain a modified aramid solution. Dimethyl sulfoxide was added to the modified aramid solution to dilute it to a mass concentration of 0.01 wt%. Then, while mechanically stirring, a 1:1 mass ratio of dimethyl sulfoxide / water mixture was added dropwise until the solution became clear, thus obtaining a mixed solution. The mixed solution was poured into a vacuum filtration device for filtration. The solid on the filter membrane was removed and deionized water was added. The solution was then ultrasonically vibrated using an ultrasonic cell disruptor to obtain an aramid nanofiber dispersion.

3. The method for preparing a nanocomposite hydrogel according to claim 2, characterized in that, When the modified aramid solution was obtained, it was stirred at a constant temperature of 30℃ for 24h; the dimethyl sulfoxide / water mixture with a mass ratio of 1:1 was added dropwise at a rate of 1mL / h.

4. The method for preparing a nanocomposite hydrogel according to claim 2, characterized in that, The amount of aramid fiber used is 0.2%-1.2% of the mass of the nanocomposite.

5. The method for preparing a nanocomposite hydrogel according to claim 2, characterized in that, The mass ratio of aramid fiber, potassium hydroxide, and dimethyl sulfoxide is 1:1.5:

99.

6. The method for preparing a nanocomposite hydrogel according to claim 2, characterized in that, The molar ratio of chloropropylene to aramid fiber is 1:

20.

7. The method for preparing a nanocomposite hydrogel according to claim 1, characterized in that, The aramid nanofiber dispersion is added to the polyacrylamide prepolymer solution and stirred evenly to obtain a mixed solution. The polyacrylamide prepolymer solution includes acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate and ammonium persulfate, and the mass ratio of acrylamide monomer, N,N-methylenebisacrylamide, sodium chloride, sodium alginate and ammonium persulfate is 2:0.002:(0.1~2):0.1:0.

08.

8. The method for preparing a nanocomposite hydrogel according to claim 1, characterized in that, The in-situ polymerization treatment involved setting the oven temperature to 60℃ and letting it stand for 1 hour.

9. A nanocomposite hydrogel, characterized in that, The nanocomposite hydrogel was prepared according to any one of claims 1 to 8.

10. The application of the nanocomposite hydrogel as described in claim 9, characterized in that, Used in flexible electronic devices.

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