Zr-MOF-PVA double-network crystal composite aerogel as well as preparation method and application thereof

Abstract

The invention provides Zr-MOF-PVA dual-network crystal composite aerogel as well as a preparation method and application thereof, and belongs to the technical field of tissue repair materials. The preparation method comprises the following steps: firstly, preparing a Zr-MOF gel matrix, inducing PVA structure reconstruction by adopting a high-energy electron beam, and realizing two-phase network crosslinking by virtue of hydrogen bond interaction between electron beam modified PVA and the Zr-MOF gel matrix, so as to obtain Zr-MOF-PVA double-network crystal composite gel; and the Zr-MOF-PVA aerogel is prepared by adopting a supercritical CO2 critical point drying technology. The Zr-MOF-PVA double-network crystal composite aerogel prepared by the invention not only has excellent mechanical properties, but also has the advantages of inflammation resistance, bacteria resistance, osteogenesis promotion, biocompatibility and the like, can be used for repairing bone related diseases, and has positive significance for the development of biocompatible bone repair materials.

Description

Technical Field

[0001] The present invention relates to the technical field of tissue repair materials, and particularly to a Zr-MOF-PVA double-network crystal composite aerogel and a preparation method and application thereof. Background Art

[0002] Zr-based MOF materials have good stability and biocompatibility and are widely used in drug loading and delivery. They can effectively remove pro-inflammatory mediators, such as nitric oxide (NO), cytokines, and reactive oxygen species (ROS). They have a porous structure and surface affinity both in vitro and in vivo, can promote cell activation, proliferation, and inhibit chronic inflammation, thereby improving the quality of wound healing. However, powdered Zr-MOF is prone to loss from the wound site and it is difficult to achieve a long-term stable therapeutic effect, which greatly limits its practical application in the field of tissue repair. Therefore, the research on the preparation of Zr-MOF gels has received extensive attention, and among them, Zr-MOF gels derived from the sol-gel method have become the current research hotspot. In most current Zr-MOF gels, the Zr-MOF crystals are mainly connected by relatively weak coordination interactions. When the solvent in the gel system is removed by freeze-drying technology, due to the lack of sufficient mechanical support, the hierarchical pore structure of the material is prone to collapse, and finally the product presents a micron-sized crystal powder morphology, which cannot meet the actual requirements of tissue repair. Summary of the Invention

[0003] The purpose of the present invention is to provide a Zr-MOF-PVA double-network crystal composite aerogel and a preparation method and application thereof, which overcome the problem that the structure of the Zr-MOF aerogel is prone to collapse.

[0004] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a preparation method of a Zr-MOF-PVA double-network crystal composite aerogel, comprising the following steps:

[0006] Mix a Zr source, an organic ligand, a regulating acid and a first dispersion solvent, and carry out a hydrolysis-coordination reaction to obtain a Zr-MOF gel matrix;

[0007] Mix polyvinyl alcohol with a second dispersion solvent, and subject the obtained precursor solution before irradiation to electron beam irradiation crosslinking to obtain a modified polyvinyl alcohol solution;

[0008] Mix the modified polyvinyl alcohol solution with the Zr-MOF gel matrix, and carry out gelation to obtain a Zr-MOF-PVA composite gel;

[0009] The Zr-MOF-PVA composite gel is dried by the supercritical CO2 critical point drying method to obtain a Zr-MOF-PVA double network crystal composite aerogel.

[0010] Preferably, the organic ligand includes terephthalic acid, 1,3,5-benzenetricarboxylic acid or phthalic acid; the regulating acid includes trifluoroacetic acid, formic acid or acetic acid; the Zr source includes ZrOCl2·8H2O, ZrCl4 or ZrSO4.

[0011] Preferably, the molar ratio of the Zr source to the organic ligand is (0.3 - 0.9):(0.1 - 0.9), and the volume ratio of the regulating acid to the first dispersion solvent is (1 - 9):(1 - 9).

[0012] Preferably, the temperature of the hydrolysis-coordination reaction is 20 - 85 °C, and the time is 5 - 50 min.

[0013] Preferably, the concentration of polyvinyl alcohol in the irradiated precursor solution is 5 - 20 wt%.

[0014] Preferably, the electron beam irradiation dose for electron beam irradiation crosslinking is 20 - 60 kGy, and the irradiation time is 5 - 30 min.

[0015] Preferably, the volume ratio of the modified polyvinyl alcohol solution to the Zr-MOF gel matrix is (0.1 - 0.9):(0.1 - 0.9); the temperature of the gelation is 15 - 45 °C, and the time is 2 - 25 min.

[0016] Preferably, the conditions of the supercritical CO2 critical point drying method include: temperature of 35 - 65 °C, pressure of 10 - 25 MPa, CO2 flow rate of 1 - 10 L / min, and replacement time of 15 - 300 min.

[0017] The present invention provides a Zr-MOF-PVA double network crystal composite aerogel prepared by the preparation method described in the above technical solution.

[0018] The present invention provides the application of the Zr-MOF-PVA double network crystal composite aerogel described in the above technical solution in the preparation of bone repair materials.

[0019] The present invention provides a preparation method of a Zr-MOF-PVA double-network crystal composite aerogel, including the preparation of a Zr-MOF gel matrix; the restructuring of the PVA structure induced by high-energy electron beams; the two-phase network crosslinking of the electron beam-modified PVA and the Zr-MOF gel matrix through hydrogen bond interaction to obtain a Zr-MOF-PVA double-network crystal composite gel; and the preparation of the Zr-MOF-PVA aerogel by using the supercritical CO2 critical point drying technology. In the preparation method of the present invention, the formation of Zr-MOF can effectively improve the mechanical strength of the gel. By means of the high-energy electron beam technology to modify PVA, the structure of PVA is accurately regulated. The modified PVA is combined with the Zr-MOF gel substrate, and the polyvinyl alcohol modified by high-energy electron beams is used to assist in enhancing the stability of Zr-MOF. The double-network composite gel is constructed by the modified PVA and the Zr-MOF gel matrix, which increases the rigidity and stretchability of the material, improves the mechanical strength of the material, overcomes the deficiency that the structure of the Zr-MOF aerogel is prone to collapse, and forms a Zr-MOF-PVA double-network crystal composite aerogel through the mild supercritical CO2 drying technology, which improves the porosity, cell adhesion and biocompatibility of the material, optimizes the service life and stability of the material, and is more helpful for the repair of bone-related diseases. In addition, using the Zr-MOF gel matrix as the substrate, Zr 4+ can achieve slow release, and thus play an anti-inflammatory, antibacterial and osteogenic effect. Therefore, the Zr-MOF-PVA double-network crystal composite aerogel prepared by the present invention not only has excellent mechanical properties, but also has the advantages of anti-inflammation, antibacterial, osteogenesis and biocompatibility, and can be used for the repair of bone-related diseases, which has positive significance for the development of biocompatible bone repair materials.

[0020] Polyvinyl alcohol (PVA) is a medical material with high biological safety and has ideal tensile and adhesion properties. It can provide support for Zr-MOF to prevent the collapse of its crystal network. However, the interaction between PVA and Zr 4+ will cause crosslinking, which in turn affects the formation of MOF crystals. In the present invention, the structure of PVA is accurately regulated by high-energy electron beam irradiation technology. After being modified by electron beam irradiation, it is more conducive to the formation of MOF crystals, and at the same time, the mechanical strength and tensile properties of PVA are significantly improved. Description of the Drawings

[0021] Figure 1 FTIR diagrams of the electron beam-irradiated modified PVA in Examples 1 to 3 and the non-electron beam-irradiated modified PVA in Comparative Example 1;

[0022] Figure 2 Macrographs of the tensile properties of the electron beam-irradiated modified PVA in Example 1 and the non-electron beam-irradiated modified PVA in Comparative Example 1;

[0023] Figure 3 XRD patterns of the double-network crystal composite aerogel prepared in Example 1 and the Zr-MOF gel matrix;

[0024] Figure 4 SEM images and Zr element distribution maps of the double-network crystal composite aerogel prepared in Example 1, where (a) is a 50-μm SEM image, (b) is a 10-μm SEM image, and (c) is the Zr element distribution map. Detailed implementation manners

[0025] In the present invention, unless otherwise specified, the raw materials or reagents required for preparation are all commercially available products well-known to those skilled in the art.

[0026] The present invention provides a method for preparing a Zr-MOF-PVA double-network crystal composite aerogel, comprising the following steps:

[0027] Mix a Zr source, an organic ligand, a regulating acid and a first dispersion solvent, and carry out a hydrolysis-coordination reaction to obtain a Zr-MOF gel matrix;

[0028] Mix polyvinyl alcohol and a second dispersion solvent, and subject the obtained precursor solution before irradiation to electron beam irradiation crosslinking to obtain a modified polyvinyl alcohol solution;

[0029] Mix the modified polyvinyl alcohol solution and the Zr-MOF gel matrix, and carry out gelation to obtain a Zr-MOF-PVA composite gel;

[0030] Adopt the supercritical CO2 critical point drying method to dry the Zr-MOF-PVA composite gel to obtain a Zr-MOF-PVA double-network crystal composite aerogel.

[0031] In the present invention, the Zr source, the organic ligand, the regulating acid and the first dispersion solvent are mixed to carry out a hydrolysis-coordination reaction to obtain a Zr-MOF gel matrix.

[0032] In the present invention, the organic ligand preferably includes terephthalic acid, 1,3,5-benzenetricarboxylic acid (H3BTC) or biphenyldicarboxylic acid; the regulating acid preferably includes trifluoroacetic acid, formic acid or acetic acid; the Zr source preferably includes ZrOCl2·8H2O, ZrCl4 or ZrSO4; the first dispersion solvent is preferably an ethanol-water mixed solvent, and the volume ratio of ethanol to water in the ethanol-water mixed solvent is preferably 1-9:1, more preferably 1:1.

[0033] In the present invention, the molar ratio of the Zr source to the organic ligand is preferably (0.3 - 0.9):(0.1 - 0.9), more preferably (0.4 - 0.8):(0.3 - 0.8), and further preferably 0.5:0.5. The volume ratio of the adjusting acid to the first dispersion solvent is preferably (1 - 9):(1 - 9), more preferably (2 - 6):(2 - 6), and further preferably 1:1.

[0034] The present invention preferably dissolves the Zr source, the organic ligand, and the adjusting acid in the first dispersion solvent and stirs them for reaction.

[0035] In the present invention, the temperature of the hydrolysis - coordination reaction is preferably 20 - 85 °C, more preferably 30 - 85 °C, and further preferably 85 °C. The time is preferably 5 - 50 min, more preferably 20 - 30 min. During the hydrolysis - coordination reaction, based on the Zr generated by the hydrolysis of the Zr source 4+ A three - dimensional porous MOF material is synthesized through the coordination between and the organic ligand, and the controllable growth of crystal morphology and size is achieved by the adjusting acid.

[0036] In the present invention, when the organic ligand is terephthalic acid, the product is UIO - 66; when the organic ligand is 1,3,5 - benzenetricarboxylic acid, the product is MOF - 808; when the organic ligand is biphenyldicarboxylic acid, the product is UIO - 67.

[0037] The present invention mixes polyvinyl alcohol with the second dispersion solvent, and subject the obtained precursor solution before irradiation to electron beam irradiation cross - linking to obtain a modified polyvinyl alcohol solution.

[0038] In the present invention, the second dispersion solvent is preferably water; the concentration of polyvinyl alcohol (PVA) in the precursor solution before irradiation is preferably 5 - 20 wt%, more preferably 8 - 15 wt%, and further preferably 10 wt%.

[0039] The present invention preferably disperses PVA in the second dispersion solvent, places it in an oil bath at 90 °C and stirs magnetically for 1 h to dissolve and mix it evenly, cools it to room temperature to obtain a precursor PVA solution before irradiation, fills it into an irradiation sample bag, and conducts electron beam irradiation treatment to obtain a modified polyvinyl alcohol solution.

[0040] In the present invention, the electron beam irradiation dose for the electron beam irradiation cross - linking is preferably 20 - 60 kGy, more preferably 30 - 50 kGy, and further preferably 40 kGy. The irradiation time is preferably 5 - 30 min, more preferably 5 - 20 min, and further preferably 5 min. During the irradiation process, molecular chain cross - linking is induced by regulating the electron beam irradiation dose, and the high - energy electron beam induces the structural reconstruction of PVA.

[0041] After obtaining the modified polyvinyl alcohol and the Zr-MOF gel matrix, the present invention mixes the modified polyvinyl alcohol and the Zr-MOF gel matrix and gels them to obtain a Zr-MOF-PVA composite gel.

[0042] In the present invention, the volume ratio of the modified polyvinyl alcohol solution to the Zr-MOF gel matrix is preferably (0.1-0.9):(0.1-0.9), more preferably (0.2-0.8):(0.2-0.8), and further preferably 0.5:0.5.

[0043] The present invention has no special limitation on the mixing of the modified polyvinyl alcohol solution and the Zr-MOF gel matrix, and it can be mixed evenly according to the processes well-known in the art.

[0044] In the present invention, the temperature of the gelation is preferably 15-45°C, more preferably 20-30°C, and further preferably 25°C; the time is preferably 2-25 min, more preferably 10-20 min, and further preferably 15 min. During the gelation process, the two-phase network crosslinking is achieved through the hydrogen bond interaction between the modified polyvinyl alcohol and the Zr-MOF gel matrix.

[0045] After obtaining the Zr-MOF-PVA composite gel, the present invention uses the supercritical CO2 critical point drying method to dry the Zr-MOF-PVA composite gel to obtain a Zr-MOF-PVA double-network crystal composite aerogel.

[0046] In the present invention, the conditions of the supercritical CO2 critical point drying method preferably include: the temperature is 35-65°C, more preferably 40-60°C, and further preferably 45°C; the pressure is 10-25 MPa, more preferably 15-20 MPa; the CO2 flow rate is 1-10 L / min, more preferably 1.5-8 L / min, and further preferably 2-5 L / min; the replacement time is 15-300 min, more preferably 50-200 min, and further preferably 150 min.

[0047] The present invention preferably places the Zr-MOF-PVA composite gel in supercritical CO2. After the temperature in the drying kettle reaches the set temperature, CO2 is filled into the kettle until the set pressure is reached, that is, the supercritical state is reached. After replacing for a specific time in the supercritical state, the CO2 in the kettle is released to make the pressure in the kettle reach the atmospheric pressure state. After cooling to room temperature, a Zr-MOF-PVA double-network crystal composite aerogel is obtained.

[0048] The present invention provides a Zr-MOF-PVA double-network crystal composite aerogel prepared by the preparation method described in the above technical solution.

[0049] The present invention provides the application of the Zr-MOF-PVA double-network crystal composite aerogel described in the above technical solution in the preparation of bone repair materials. The present invention has no special limitation on the method of the application, and it can be applied according to the methods well-known in the art.

[0050] The specific embodiments of the present invention will be described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. The experimental methods described in the embodiments of the present invention are all conventional methods unless otherwise specified.

[0051] The following experimental methods and detection methods are all conventional methods unless otherwise specified; the following reagents and raw materials are all commercially available unless otherwise specified.

[0052] Example 1

[0053] ① Dissolve 0.16 g of ZrOCl2·8H2O (0.5 mmol), 0.1 g of H3BTC (0.5 mmol) and 20 mL of formic acid in 20 mL of ethanol / water mixed solvent (the volume ratio of ethanol to water is 1:1), and stir and react at 85 °C for 30 min to obtain a Zr-MOF gel matrix;

[0054] ② Disperse 2 g of PVA into 20 mL of deionized water, place it in an oil bath at 90 °C and stir magnetically for 1 h to dissolve and mix it evenly, cool to room temperature to obtain a pre-irradiation precursor PVA solution, put it into an irradiation sample bag, and perform electron beam irradiation treatment at an irradiation dose of 20 kGy for 5 min to obtain a modified PVA solution, denoted as PVA-EB20;

[0055] ③ Mix the Zr-MOF gel matrix prepared in steps ① and ② with the modified PVA solution according to a volume ratio of 0.5:0.5, and gel at 25 °C for 15 min to obtain a Zr-MOF-PVA double-network crystal composite wet gel;

[0056] ④ Place the Zr-MOF-PVA double-network crystal composite wet gel in step ③ for supercritical CO2 drying. When the temperature in the drying kettle reaches 45 °C, charge CO2 into the kettle, the CO2 flow rate is 2 L / min, and when the pressure in the drying kettle is 15 MPa, it reaches the supercritical state, and displace for 150 min in the supercritical state; after the end, release the CO2 in the kettle to make the pressure in the kettle reach the atmospheric state, and cool to room temperature to obtain a Zr-MOF-PVA double-network crystal composite aerogel, denoted as Zr-MOF-PVA-20.

[0057] Example 2

[0058] ① Dissolve 0.16 g of ZrOCl₂·8H₂O, 0.1 g of H₃BTC and 20 mL of formic acid in 20 mL of an ethanol / water mixed solvent (volume ratio of ethanol to water is 1:1), and stir and react at 85 °C for 30 min to obtain a Zr-MOF gel matrix;

[0059] ② Disperse 2 g of PVA in 20 mL of deionized water, place it in an oil bath at 90 °C and stir magnetically for 1 h to dissolve and mix it evenly. Cool to room temperature to obtain a pre-irradiation PVA solution. Load it into an irradiation sample bag and perform electron beam irradiation treatment at an irradiation dose of 40 kGy for 5 min to obtain a modified PVA solution, denoted as PVA-EB40;

[0060] ③ Mix the Zr-MOF gel matrix prepared in steps ① and ② with the modified PVA solution according to a volume ratio of 0.5:0.5, and gel at 25 °C for 15 min to obtain a Zr-MOF-PVA double-network crystal composite wet gel;

[0061] ④ Place the Zr-MOF-PVA double-network crystal composite wet gel in step ③ for supercritical CO₂ drying. After the temperature in the drying kettle reaches 45 °C, fill CO₂ into the kettle. When the CO₂ flow rate is 2 L / min and the pressure in the drying kettle is 15 MPa, it reaches the supercritical state. Replace for 150 min in the supercritical state. After that, release the CO₂ in the kettle to make the pressure in the kettle reach the atmospheric pressure state. After cooling to room temperature, obtain a Zr-MOF-PVA double-network crystal composite aerogel, denoted as Zr-MOF-PVA-40.

[0062] Example 3

[0063] ① Dissolve 0.16 g of ZrOCl₂·8H₂O, 0.1 g of H₃BTC and 20 mL of formic acid in 20 mL of an ethanol / water mixed solvent (volume ratio of ethanol to water is 1:1), and stir and react at 85 °C for 30 min to obtain a Zr-MOF gel substrate;

[0064] ② Disperse 2 g of PVA in 20 mL of deionized water, place it in an oil bath at 90 °C and stir magnetically for 1 h to dissolve and mix it evenly. Cool to room temperature to obtain a pre-irradiation PVA solution. Load it into an irradiation sample bag and perform electron beam irradiation treatment at an irradiation dose of 60 kGy for 5 min to obtain a modified PVA solution, denoted as PVA-EB60;

[0065] ③ Mix the Zr-MOF gel matrix prepared in steps ① and ② with the modified PVA solution according to a volume ratio of 0.5:0.5, and gel at 25 °C for 15 min to obtain a Zr-MOF-PVA double-network crystal composite wet gel;

[0066] ④ Place the Zr-MOF-PVA double-network crystal composite wet gel in step ③ under supercritical CO2 drying. After the temperature in the drying kettle reaches 45 °C, charge CO2 into the kettle. When the CO2 flow rate is 2 L / min and the pressure in the drying kettle is 15 MPa, it reaches the supercritical state. Replace for 150 min under the supercritical state. After completion, release the CO2 in the kettle to make the pressure in the kettle reach the atmospheric pressure state. After cooling to room temperature, a Zr-MOF-PVA double-network crystal composite aerogel is obtained, denoted as Zr-MOF-PVA-60.

[0067] Comparative Example 1

[0068] ① Prepare a Zr-MOF gel substrate according to Example 1;

[0069] ② Disperse 2 g of PVA into 20 mL of deionized water, place it in an oil bath at 90 °C and stir magnetically for 1 h to dissolve and mix it evenly, and cool to room temperature to obtain a PVA solution without electron beam irradiation modification;

[0070] ③ Mix the Zr-MOF gel matrix in step ① with the PVA solution in step ② at a volume ratio of 0.5:0.5, and gel at 25 °C for 15 min to obtain a Zr-MOF-PVA double-network crystal composite wet gel;

[0071] ④ Place the Zr-MOF-PVA double-network crystal composite wet gel in step ③ under supercritical CO2 drying. After the temperature in the drying kettle reaches 45 °C, charge CO2 into the kettle. When the CO2 flow rate is 2 L / min and the pressure in the drying kettle is 15 MPa, it reaches the supercritical state; replace for 150 min under the supercritical state. After completion, release the CO2 in the kettle to make the pressure in the kettle reach the atmospheric pressure state. After cooling to room temperature, a Zr-MOF-PVA double-network crystal composite aerogel is obtained, denoted as Zr-MOF-PVA.

[0072] Figure 1 FTIR diagrams of PVA modified by electron beam irradiation in Examples 1 to 3 and PVA without electron beam irradiation modification in Comparative Example 1. As Figure 1 shown, obvious changes occurred in the characteristic peaks of PVA after electron beam treatment: the bending vibration intensity of the -CH2 group at 1413 cm -1 and 1327 cm -1 increased significantly; the stretching vibration absorption peak of the C-O bond at 1130 cm -1 increased significantly; at the same time, the increase in the characteristic peak intensities at 992 cm -1 and 941 cm -1 can be attributed to the strengthening of the out-of-plane bending vibration of the C-H bond. The evolution law of these characteristic peaks indicates that electron beam irradiation induced the modification of the PVA molecular chain.

[0073] Figure 2 Macrographs of the electron beam irradiated modified PVA in Example 1 and the unmodified PVA in Comparative Example 1. Obviously, the tensile properties of the PVA after electron beam irradiation modification are significantly better than those of the unmodified PVA.

[0074] Figure 3 XRD patterns of the double-network crystal composite aerogel prepared in Example 1 and the Zr-MOF gel matrix. As Figure 3 shown, obvious characteristic peaks of Zr-MOF crystals appear at 2θ = 4.4°, 8.3° and 8.7°, indicating good crystallinity in the aerogel.

[0075] Figure 4 SEM images and Zr element distribution maps of the double-network crystal composite aerogel prepared in Example 1, where (a) is a 50 μm SEM image, (b) is a 10 μm SEM image, and (c) is a Zr element distribution map; from Figure 4 which, micron-sized pore sizes and the uniform distribution of Zr elements can be clearly observed.

[0076] Existing studies have shown that the presence of micron-sized pores contributes to the proliferation and attachment of cells during bone repair and the adsorption of surrounding tissue fluid. The presence and uniform distribution of Zr elements will contribute to subsequent slow release and tissue applications (anti-inflammatory, antibacterial, and osteogenic), indicating that the double-network crystal composite aerogel of the present invention has the potential for tissue applications.

[0077] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A preparation method of a Zr-MOF-PVA double-network crystal composite aerogel, characterized in that, It includes the following steps: Mix a Zr source, an organic ligand, a regulating acid and a first dispersion solvent, and carry out a hydrolysis-coordination reaction to obtain a Zr-MOF gel matrix; Mix polyvinyl alcohol with a second dispersion solvent, and subject the obtained precursor solution before irradiation to electron beam irradiation crosslinking to obtain a modified polyvinyl alcohol solution; Mix the modified polyvinyl alcohol solution with the Zr-MOF gel matrix and carry out gelation to obtain a Zr-MOF-PVA composite gel; Adopt the supercritical CO2 critical point drying method to dry the Zr-MOF-PVA composite gel to obtain a Zr-MOF-PVA double-network crystal composite aerogel.

2. The preparation method according to claim 1, wherein The organic ligand includes terephthalic acid, 1,3,5-benzenetricarboxylic acid or phthalic acid; the regulating acid includes trifluoroacetic acid, formic acid or acetic acid; the Zr source includes ZrOCl2·8H2O, ZrCl4 or ZrSO4.

3. The preparation method according to claim 1, wherein, The molar ratio of the Zr source to the organic ligand is (0.3-0.9):(0.1-0.9), and the volume ratio of the regulating acid to the first dispersion solvent is (1-9):(1-9).

4. The preparation method according to claim 1 or 2 or 3, characterized in that, The temperature of the hydrolysis-coordination reaction is 20-85 °C, and the time is 5-50 min.

5. The preparation method according to claim 1, characterized in that, The concentration of polyvinyl alcohol in the precursor solution before irradiation is 5-20 wt%.

6. The preparation method according to claim 1 or 5, characterized in that, The electron beam irradiation dose for the electron beam irradiation crosslinking is 20-60 kGy, and the irradiation time is 5-30 min.

7. The preparation method according to claim 1, wherein The volume ratio of the modified polyvinyl alcohol solution to the Zr-MOF gel matrix is (0.1-0.9):(0.1-0.9); the temperature of the gelation is 15-45 °C, and the time is 2-25 min.

8. The preparation method according to claim 1, characterized in that, The conditions of the supercritical CO2 critical point drying method include: temperature 35-65 °C, pressure 10-25 MPa, CO2 flow rate 1-10 L / min, replacement time 15-300 min.

9. The Zr-MOF-PVA double-network crystal composite aerogel prepared by the preparation method according to any one of claims 1-8.

10. Use of the Zr-MOF-PVA double-network crystal composite aerogel according to claim 9 in the preparation of a bone repair material.

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