Two-dimensional honeycomb-shaped and three-dimensional spinous process-shaped double-coupled microstructure nanofiber membrane as well as preparation method and application thereof

Abstract

The invention relates to the technical field of nanofiber membranes, in particular to a two-dimensional honeycomb-shaped and three-dimensional spinous process-shaped double-coupling microstructure nanofiber membrane and a preparation method and application thereof.The preparation method comprises the steps that 1, thermoplastic polyurethane (TPU) is dissolved in an organic solvent, and a homogeneous spinning solution is obtained after heating and stirring; 2, performing oxygen plasma treatment on the foam template to enable the surface of the foam template to present negative potential; and 3, injecting the homogeneous spinning solution into an injector, carrying out electrostatic spinning in a high-voltage electrostatic field by taking foam as a collector, controlling the flow rate of the spinning solution through a boost pump, stripping the nanofiber membrane from the surface of the foam after spinning is finished, and drying to obtain the two-dimensional honeycomb and three-dimensional spinous process double-coupled microstructure nanofiber membrane. By introducing the double-coupling microstructure, the maximum tensile strain of the nanofiber membrane is improved by 77%, the maximum tensile stress is improved by 88%, and the residual strain and the residual stress are respectively reduced by 27% and 34% after 100 times of cyclic stretching.

Description

Technical Field

[0001] The present invention relates to the technical field of nanofiber membranes, and in particular to a two-dimensional honeycomb-shaped and three-dimensional spinous process-shaped dual-coupled microstructure nanofiber membrane and a preparation method and application thereof. Background Art

[0002] At present, with the rapid development of wearable bioelectronics technology, flexible nanofiber membranes with high tensile mechanical properties have become a research hotspot. In the prior art, patent CN202411484317.7 proposed a nanofiber membrane based on an electrospinning-electrostatic spraying composite method to prepare a new type of heterogeneous material stack, but it is limited by the stress concentration effect of its two-dimensional random nanofiber network, and there are problems of dynamic response hysteresis and insufficient mechanical durability. Patent CN202411079484.3 uses a polyvinylidene fluoride-based mixed solution phase separation method to prepare a two-dimensional coupled microstructure nanofiber membrane, but its maximum tensile strain is less than 30%.

[0003] The root cause of the above technical bottleneck lies in the random and disordered distribution characteristics of traditional electrospun nanofiber membranes, which leads to the performance game between mechanical tensile performance and cyclic tensile performance of existing nanofiber membranes. Therefore, developing nanofiber membranes with cross-scale ordered microstructures to achieve synergistic optimization of mechanical tensile and cyclic mechanical properties is a key direction to break through the existing technical barriers. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings existing in the prior art, and to propose a two-dimensional honeycomb and three-dimensional spiny dual-coupled microstructure nanofiber membrane and its preparation method and application. The prepared nanofiber membrane has a cross-scale ordered microstructure and can achieve synergistic optimization of mechanical tensile and cyclic mechanical properties.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane comprises the following steps:

[0007] Step 1: dissolving thermoplastic polyurethane (TPU) in an organic solvent, heating and stirring to obtain a homogeneous spinning solution;

[0008] Step 2: treating the foam template with oxygen plasma to make its surface present a negative potential;

[0009] Step 3: Inject the homogenous spinning solution into a syringe, use the foam as a collector, and perform electrospinning under a high-voltage electrostatic field. Control the flow rate of the spinning solution by a propulsion pump. After spinning, peel off the nanofiber membrane from the foam surface and dry it to obtain a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure nanofiber membrane.

[0010] Preferably, in step 1, the organic solvent is selected from any one or more of dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF), dimethylacetamide (DMAc), and N-methylpyrrolidone (NMP); the mass ratio of thermoplastic polyurethane to organic solvent is 1:5-20, the heating temperature is 70-100° C., and the stirring time is 12-24 hours.

[0011] Preferably, in step 2, the foam template is selected from any one of polyurethane foam, polystyrene foam, polyethylene foam, polypropylene foam, silicone foam, melamine foam, polyethersulfone foam, and polyimide foam; the power of oxygen plasma treatment is 1000 to 1500 W, the treatment time is 40 to 90 seconds, and the foam surface potential is -1 kV to -2.5 kV.

[0012] Preferably, in step 3, the voltage of the high-voltage electrostatic field is 15 to 30 kV, the distance between the foam and the syringe needle tip is 15 to 25 cm, the spinning solution flow rate is 0.1 to 2.5 mL / h, and the drying time is 12 to 24 hours. In the electrospinning process, the spinning solution forms nanofibers under the action of the high-voltage electrostatic field and is deposited on the surface of the foam template to form a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure.

[0013] The present invention also provides a two-dimensional honeycomb and three-dimensional spinous process dual-coupled microstructure nanofiber membrane prepared by the above-mentioned preparation method, wherein the nanofiber membrane has a cross-scale ordered microstructure, including a two-dimensional honeycomb network and three-dimensional spinous process protrusions.

[0014] Preferably, the maximum tensile strain of the nanofiber membrane is 200%, the maximum tensile stress is 28.7 MPa, and the residual strain after 100 cycles of stretching is 5.14%.

[0015] An application of a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane prepared by the above preparation method in flexible electronic devices, sensors, filter materials or biomedical materials.

[0016] A flexible electronic device comprises a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane.

[0017] A sensor comprises a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane.

[0018] A filter material comprises a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane.

[0019] A biomedical material comprises a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane.

[0020] By adopting the above technical scheme: using thermoplastic polyurethane (TPU) as the electrospinning base material, using negatively charged foam as a collecting plate, under the action of a high-voltage electrostatic field, the positively charged TPU nanofibers are preferentially adsorbed and deposited on the surface of the foam skeleton to form a two-dimensional honeycomb structure nanofiber membrane. As the deposition amount increases, a three-dimensional spinous microstructure is further formed on the surface of the two-dimensional honeycomb structure, thereby constructing a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure system. Compared with the traditional two-dimensional electrospinning nanofiber membrane, the dual-coupled microstructure introduced in the present invention increases the maximum tensile strain of the nanofiber membrane by 77%, the maximum tensile stress by 88%, and the residual strain and residual stress after 100 cycles of stretching are reduced by 27% and 34%, respectively.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The two-dimensional honeycomb and three-dimensional spinous process dual-coupled microstructure nanofiber membrane prepared by the present invention has excellent mechanical properties, with the maximum tensile strain increased by 77%, the maximum tensile stress increased by 88%, and the residual strain and residual stress reduced by 27% and 34% respectively after 100 cycles of stretching.

[0023] 2. The preparation method of the present invention is simple, easy to operate and low in cost, and is suitable for large-scale production.

[0024] 3. The present invention solves the performance bottleneck of traditional electrospinning nanofiber membranes through dual-coupling microstructure design, provides a new technical path for the development of nanofiber membranes with excellent mechanical properties, and has broad application prospects in medical health monitoring, human-computer interaction and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The figure is a flow chart of the preparation of the dual-coupled microstructure nanofiber membrane of the present invention;

[0026] Figure 2 The scanning electron microscope (SEM) images of the conventional randomly distributed nanofiber membrane and the dual-coupled microstructure nanofiber membrane of the present invention and the optical image and three-dimensional contour diagram of the three-dimensional spinous process microstructure;

[0027] Figure 3 This is a comparison chart of the maximum tensile mechanical properties of the dual-coupled microstructure nanofiber membrane of the present invention and the traditional randomly distributed nanofiber membrane, as well as the residual strain and residual stress after 100 cycles of stretching. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings, so that those skilled in the art can better understand the advantages and features of the present invention, thereby making a clearer definition of the protection scope of the present invention. The embodiments described in the present invention are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] Thermoplastic polyurethane and dimethylformamide were mixed in a mass ratio of 1:10, heated and stirred at 80°C for 18 hours to obtain a homogeneous spinning solution. Polyurethane foam was selected as a template and treated with an oxygen plasma treatment instrument at a power of 1200W for 60 seconds to make the foam surface present a negative potential of -1.8kV. The prepared spinning solution was injected into a syringe and spun using a high-voltage electrostatic field with a voltage set to 20kV. The foam template was used as a collector, 20cm away from the needle tip of the syringe, and the spinning solution flow rate was controlled to 0.5mL / h. After spinning, the nanofiber membrane was peeled off from the foam surface and placed in a fume hood to dry for 18 hours to obtain a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure nanofiber membrane.

[0031] Figure 1 It is a flow chart of the preparation of dual-coupled microstructured nanofiber membrane; Figure 2 The figure shows the appearance comparison of a dual-coupled microstructure nanofiber membrane and a dual-coupled microstructure nanofiber membrane, wherein (a) is a traditional randomly distributed nanofiber membrane; (b) is a two-dimensional honeycomb structure nanofiber membrane; (c) is a three-dimensional spiny microstructure on the surface of a two-dimensional honeycomb structure nanofiber membrane; (d) is a three-dimensional contour diagram of the dual-coupled microstructure nanofiber membrane, from which it can be seen that the height of the three-dimensional spiny microstructure is 5-15 microns; this illustrates that the two-dimensional honeycomb structure and the three-dimensional spiny microstructure are successfully prepared on the surface of the dual-coupled microstructure nanofiber membrane of the present invention.

[0032] Example 2

[0033] Thermoplastic polyurethane and N-methylpyrrolidone were mixed in a mass ratio of 1:15, heated and stirred at 90°C for 24 hours to obtain a homogeneous spinning solution. Polystyrene foam was selected as a template and treated with an oxygen plasma treatment instrument at a power of 1500W for 90 seconds to make the foam surface present a negative potential of -2.5kV. The prepared spinning solution was injected into a syringe and spun using a high-voltage electrostatic field with a voltage set to 25kV. The foam template was used as a collector, 25cm away from the needle tip of the syringe, and the spinning solution flow rate was controlled to 1.0mL / h. After spinning, the nanofiber membrane was peeled off from the foam surface and placed in a fume hood to dry for 24 hours to obtain a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure nanofiber membrane.

[0034] like Figure 3 As shown, Figure 3 It is a mechanical test diagram of the dual-coupled microstructure nanofiber membrane obtained in Example 2, wherein (a) is the stress-strain diagram of maximum stretching; (b) is the comparison diagram of residual strain and residual stress after 100 cycles of stretching; it shows that the maximum tensile strain and stress as well as the residual strain and residual stress performance after 100 cycles of stretching are not as good as those in Example 1, but better than the randomly distributed nanofiber membrane obtained by traditional electrospinning.

[0035] Example 3

[0036] Thermoplastic polyurethane and tetrahydrofuran were mixed in a mass ratio of 1:5, heated and stirred at 70°C for 12 hours to obtain a homogeneous spinning solution. Polyethylene foam was selected as a template and treated with an oxygen plasma treatment instrument at a power of 1000W for 40 seconds to make the foam surface present a negative potential of -1.0kV. The prepared spinning solution was injected into a syringe and spun using a high-voltage electrostatic field with a voltage set to 15kV. The foam template was used as a collector, 15cm away from the syringe needle tip, and the spinning solution flow rate was controlled to 0.1mL / h. After spinning, the nanofiber membrane was peeled off from the foam surface and placed in a fume hood to dry for 12 hours to obtain a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure nanofiber membrane.

[0037] like Figure 3 As shown, Figure 3 It is a mechanical test diagram of the dual-coupled microstructure nanofiber membrane obtained in Example 3, showing that the maximum tensile strain and stress as well as the residual strain and residual stress after 100 cycles of stretching are not as good as those in Example 1, but better than the randomly distributed nanofiber membrane obtained by traditional electrospinning.

[0038] In summary, the two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure nanofiber membrane prepared by the present invention has excellent mechanical properties, with the maximum tensile strain increased by 77%, the maximum tensile stress increased by 88%, and the residual strain and residual stress after 100 cycles of stretching reduced by 27% and 34%, respectively.

[0039] The description and practice disclosed in the present invention are easy to think and understand for ordinary technicians in the technical field, and several improvements and modifications can be made without departing from the principles of the present invention. Therefore, modifications or improvements made without departing from the spirit of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane, characterized in that: The steps include: Step 1: dissolving thermoplastic polyurethane TPU in an organic solvent, heating and stirring to obtain a homogeneous spinning solution; Step 2: treating the foam template with oxygen plasma to make its surface present a negative potential; Step 3: Inject the homogenous spinning solution into a syringe, use the foam as a collector, and perform electrospinning under a high-voltage electrostatic field. Control the flow rate of the spinning solution by a propulsion pump. After spinning, peel off the nanofiber membrane from the foam surface and dry it to obtain a two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructure nanofiber membrane.

2. The method for preparing a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane according to claim 1, characterized in that: In the step 1, the organic solvent is selected from any one or more of dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF), dimethylacetamide (DMAc), and N-methylpyrrolidone (NMP); the mass ratio of thermoplastic polyurethane to organic solvent is 1:5-20, the heating temperature is 70-100° C., and the stirring time is 12-24 hours.

3. The method for preparing a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane according to claim 1, characterized in that: In the step 2, the foam template is selected from any one of polyurethane foam, polystyrene foam, polyethylene foam, polypropylene foam, silicone foam, melamine foam, polyethersulfone foam, and polyimide foam; the power of the oxygen plasma treatment is 1000 to 1500 W, the treatment time is 40 to 90 seconds, and the foam surface potential is -1 kV to -2.5 kV.

4. The method for preparing a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane according to claim 1, characterized in that: In the step 3, the voltage of the high-voltage electrostatic field is 15 to 30 kV, the distance between the foam and the syringe needle tip is 15 to 25 cm, the spinning solution flow rate is 0.1 to 2.5 mL / h, and the drying time is 12 to 24 hours.

5. A two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane prepared by the preparation method according to any one of claims 1 to 4, characterized in that: The nanofiber membrane has a cross-scale ordered microstructure, including a two-dimensional honeycomb network and three-dimensional spinous protrusions; the maximum tensile strain of the nanofiber membrane is 200%, the maximum tensile stress is 28.7 MPa, and the residual strain after 100 cycles of stretching is 5.14%.

6. An application of a two-dimensional honeycomb-shaped and three-dimensional spinous-shaped dual-coupled microstructure nanofiber membrane prepared by the preparation method described in any one of claims 1 to 4 in flexible electronic devices, sensors, filter materials or biomedical materials.

7. A flexible electronic device, characterized in that: It comprises the two-dimensional honeycomb and three-dimensional spinous process dual-coupled microstructure nanofiber membrane as described in claim 5.

8. A sensor, characterized in that: It comprises the two-dimensional honeycomb and three-dimensional spinous process dual-coupled microstructure nanofiber membrane as described in claim 5.

9. A filter material, characterized in that: It comprises the two-dimensional honeycomb and three-dimensional spinous process dual-coupled microstructure nanofiber membrane as described in claim 5.

10. A biomedical material, characterized in that: It comprises the two-dimensional honeycomb and three-dimensional spinous process dual-coupled microstructure nanofiber membrane as described in claim 5.

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