A self-repairing method and application of carbon fiber hydrogel

Abstract

The present invention relates to the field of material self-repair technology, and in particular to a self-repair method and application of carbon fiber hydrogel, comprising the following steps: S1, placing a broken hydrogel composite material into a mold for fixation; S2, placing the mold containing the hydrogel composite material into a microwave generator, and adjusting the microwave power of the microwave generator; S3, when an electric spark phenomenon is observed in the observation window of the microwave generator, taking out the mold with the hydrogel composite material; S4, physically crosslinking the hydrogel composite material treated by microwaves in S3 to obtain a repaired hydrogel. The present invention adopts the above-mentioned self-repair method and application of carbon fiber hydrogel, which solves the problem in the prior art that damaged hydrogels are difficult to repair after multiple crosslinking to form a stable network.

Description

Technical Field

[0001] The invention relates to the technical field of material self-repairing, and in particular to a self-repairing method of carbon fiber-containing hydrogel and application thereof. Background Art

[0002] Gel refers to a dispersed system in which swollen polymers are interconnected to form a three-dimensional network structure, and the gaps in the network structure are filled with liquid media. Polymer water-based gel (also known as hydrogel) is an important material in the field of basic research. Polyvinyl alcohol (PVA) is a widely used water-soluble polymer material. The hydrogel prepared by repeated freezing has good mechanical properties and biocompatibility. Adding some reinforcing phases (such as carbon fibers, carbon nanotubes or graphene) can significantly improve its mechanical properties.

[0003] At present, there are many studies on the mechanical properties of hydrogel composites, but there are fewer studies on the repair of polyvinyl alcohol composite hydrogel materials after damage under certain conditions. The existing hydrogel self-repair is mostly carried out after damage with a small number of cross-linking times, and the damaged hydrogel is difficult to repair after it has been cross-linked multiple times to form a stable network. Summary of the invention

[0004] The purpose of the present invention is to provide a self-repairing method of carbon fiber-containing hydrogel and its application, which solves the problem in the prior art that damaged hydrogels are difficult to repair after forming a stable network through multiple cross-linking.

[0005] To achieve the above object, the present invention provides a self-repairing method of carbon fiber hydrogel, comprising the following steps:

[0006] S1, placing the broken hydrogel composite into a mold for fixation;

[0007] S2, placing the mold containing the hydrogel composite material into a microwave generator, and adjusting the microwave power of the microwave generator;

[0008] S3, when electric spark phenomenon is observed in the observation window of the microwave generating device, the mold with the hydrogel composite material is taken out to obtain the hydrogel composite material after microwave treatment;

[0009] S4. Physically cross-linking the hydrogel composite material treated by microwaves in S3 to obtain a repaired hydrogel.

[0010] Preferably, in S1, the material of the mold is polytetrafluoroethylene.

[0011] Preferably, in S2, the microwave frequency of the microwave generating device is 2.45 GHz, and the microwave power is 3 kW.

[0012] Preferably, in S2, the microwave generating device is a microwave oven.

[0013] Preferably, in S4, the physical crosslinking is to store the hydrogel composite material after microwave treatment in a refrigerator, and then take it out of the refrigerator and store it in an oven.

[0014] Preferably, the storage temperature in the refrigerator is -25°C, the storage time in the refrigerator is 22 hours, and the storage temperature in the oven is 25°C, and the storage time in the oven is 2 hours.

[0015] An application of a self-repairing method for a carbon fiber-containing hydrogel. The self-repairing method for a carbon fiber-containing hydrogel as described above is applied to the repair of a polyvinyl alcohol hydrogel containing carbon fibers.

[0016] Mechanism of the Invention

[0017] Microwave energy interacts with the hydrogel, breaking up the stable hydrogen bonds formed. The good coupling properties between carbon fiber and microwaves will aggravate this phenomenon and ultimately achieve repair.

[0018] Beneficial effects of the present invention:

[0019] The present invention provides a self-repair method for carbon fiber hydrogel, which can be used to self-repair carbon fiber hydrogel composite materials that have undergone multiple freeze-crosslinking. After repair, the composite material still has the same properties as the raw material, and can be repaired multiple times using this method.

[0020] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of a microwave generating device used in an embodiment of the present invention;

[0022] Figure 2 is a comparison diagram of the carbon fiber-containing hydrogel composite material before and after repair according to an embodiment of the present invention;

[0023] in, Figure 2 a in the figure is a schematic diagram of the carbon fiber hydrogel composite material before it is damaged. Figure 2 b is a schematic diagram of the damaged carbon fiber hydrogel composite material. Figure 2 c is a schematic diagram of the self-repaired carbon fiber hydrogel composite material;

[0024] Figure 3 It is a schematic diagram of the tensile strength of the polyvinyl alcohol hydrogel containing carbon fibers before damage and after repair according to an embodiment of the present invention;

[0025] Figure 4This is a schematic diagram of a repaired carbon fiber-containing hydrogel composite material according to a comparative example of the present invention;

[0026] in, Figure 4 a in the figure is a schematic diagram of the carbon fiber hydrogel composite material repaired 1 minute later. Figure 4 b is a schematic diagram of the carbon fiber hydrogel composite material repaired 10 minutes later. Figure 4 Figure c is a schematic diagram of the carbon fiber hydrogel composite material after repair for 30 minutes.

[0027] Reference numerals:

[0028] 1. Microwave generating device; 2. Mould. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments. Unless otherwise defined, the technical terms or scientific terms used in the present invention should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs. The above-mentioned features or features mentioned in the specific examples mentioned in the present invention can be combined arbitrarily, and these specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0030] The carbon fiber-containing polyvinyl alcohol hydrogel used in the present invention is prepared by the following method:

[0031] (1) Place carbon fiber in a beaker containing deionized water, and place the beaker on an oil bath heating device containing silicone oil for heating and stirring;

[0032] (2) When the temperature in the beaker reaches 90°C and stabilizes, add weighed polyvinyl alcohol; the mass ratio of carbon fiber: polyvinyl alcohol is 1:2, and the mass ratio of polyvinyl alcohol: deionized water is 15:85, then stir thoroughly for 3 hours in an oil bath at 90°C, take it out and pour it into the mold for preparing the hydrogel;

[0033] (3) Performing physical crosslinking, the mold of step (2) is placed in a refrigerator at a temperature of -25°C for 22 hours, and then the mold is taken out of the refrigerator and placed in an oven at 25°C for 2 hours;

[0034] (4) After taking out, polyvinyl alcohol hydrogel containing carbon fibers was obtained, and its mechanical properties were measured, and the tensile strength was 1111.85 kPa.

[0035] Example

[0036] See also Figure 1 to Figure 2 As shown in the figure, the present invention provides a self-repairing method of carbon fiber hydrogel, comprising the following steps:

[0037] S1, preparing a damaged carbon fiber-containing polyvinyl alcohol hydrogel that has been cross-linked multiple times to form a stable network, and placing it into mold 2 for fixation;

[0038] S2, placing the mold 2 of step S1 in a microwave generator 1, adjusting the microwave frequency of the microwave generator 1 to 2.45 GHz and the microwave power to 3 kW;

[0039] S3, when electric spark phenomenon is observed in the observation window of the microwave generating device 1, the mold 2 is taken out to obtain the hydrogel composite material after microwave treatment;

[0040] S4. The hydrogel composite material treated by microwaves in S3 was placed in a refrigerator at -25°C for 22 hours, then taken out of the refrigerator and placed in an oven at 25°C for 2 hours to obtain the repaired hydrogel. The mechanical properties were measured again, and the tensile strength was 1112.9 kPa.

[0041] Comparative Example

[0042] The damaged carbon fiber-containing polyvinyl alcohol hydrogel after multiple cross-linking to form a stable network is repaired by the natural static method in the prior art, that is, the ports of the hydrogel are overlapped and placed, and the repaired hydrogel is obtained after a period of time.

[0043] Figure 3 Schematic diagram of the tensile strength of the polyvinyl alcohol hydrogel containing carbon fiber before damage and after repair. Figure 3 As shown, by comparing the mechanical properties measured in the example with the mechanical properties of the prepared polyvinyl alcohol hydrogel containing carbon fibers, it can be seen that the self-repairing method of the present invention can be used to repair the damaged carbon fiber hydrogel composite material after multiple cross-linking to form a stable network, and the hydrogel composite material still has the same properties as the raw material after repair.

[0044] Figure 4 Schematic diagram of the repaired carbon fiber hydrogel composite material of the comparative example of the present invention, as shown in Figure 4 As shown, the natural standing method of the existing technology cannot repair the damaged carbon fiber-containing polyvinyl alcohol hydrogel after multiple cross-linking to form a stable network. This is because this repair method has certain limitations on the concentration of the PVA solution and the freezing and thawing during the physical cross-linking process, and the strength of the repaired sample will decrease to a certain extent compared to before. As the number of cross-linking times increases, this repair property will disappear.

[0045] By comparing the comparative examples with the embodiments, it can be seen that the repair method proposed by the present invention still has a repair effect on gels with a large number of cross-linking times, the repair efficiency is close to 100%, and theoretically it can be repaired an unlimited number of times.

[0046] Therefore, the present invention adopts the above-mentioned self-repair method of carbon fiber hydrogel, which can be used for self-repair of carbon fiber hydrogel composite materials damaged after multiple cross-linking, and after repair, it still has the same properties as the raw materials.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A self-repairing method containing carbon fiber hydrogel, characterized in that: The following steps are included: S1, placing the broken hydrogel composite into a mold for fixation; Wherein, the hydrogel composite material is formed by hydrogen bond cross-linking, and the hydrogel composite material is a polyvinyl alcohol hydrogel containing carbon fibers; S2, placing the mold containing the hydrogel composite material into a microwave generator, and adjusting the microwave power of the microwave generator; S3, when electric spark phenomenon is observed in the observation window of the microwave generating device, the mold with the hydrogel composite material is taken out to obtain the hydrogel composite material after microwave treatment; S4, physically cross-linking the hydrogel composite material after microwave treatment in S3 to obtain a repaired hydrogel; In S4, the physical crosslinking is to store the hydrogel composite material after microwave treatment in a refrigerator, and then take it out of the refrigerator and store it in an oven.

2. The self-repairing method of carbon fiber hydrogel according to claim 1, characterized in that: In S1, the material of the mold is polytetrafluoroethylene.

3. The self-repairing method of carbon fiber hydrogel according to claim 1, characterized in that: In S2, the microwave frequency of the microwave generating device is 2.45 GHz, and the microwave power is 3 kW.

4. The self-repairing method of carbon fiber hydrogel according to claim 1, characterized in that: In S2, the microwave generating device is a microwave oven.

5. The self-repairing method of carbon fiber-containing hydrogel according to claim 1, characterized in that: The storage temperature in the refrigerator is -25℃, the storage time in the refrigerator is 22h, the storage temperature in the oven is 25℃, and the storage time in the oven is 2h.

6. Application of a self-repairing method containing carbon fiber hydrogel, characterized in that: A self-repairing method for a carbon fiber-containing hydrogel as described in any one of claims 1 to 5 is applied to the repair of a polyvinyl alcohol hydrogel containing carbon fibers.

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