An antibacterial polyimide composite material and a preparation method thereof

Abstract

This invention relates to the field of composite material technology, specifically to an antibacterial polyimide composite material and its preparation method. An inorganic antibacterial agent, macromolecular chain sugars, and water-soluble calcium are added to water to form a dispersion. A phosphate solution is added dropwise to the dispersion while controlling the temperature within the range of 30-65°C, and a precipitant solution is added dropwise simultaneously. The mixture is aged under alkaline conditions and subsequently calcined to obtain a hydroxyapatite@inorganic antibacterial agent composite. A coating solution containing this substance is prepared, and a porous polyimide part is immersed in the coating solution under vacuum. After draining and drying, the antibacterial polyimide composite material is obtained. The composite material of this invention exhibits good antibacterial properties and biological activity while ensuring mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of composite material technology, specifically to an antibacterial polyimide composite material and its preparation method. Background Technology

[0002] Polyimide (PI) is widely used in medical implant materials due to its excellent mechanical properties, high-temperature resistance, and biocompatibility. However, the bioinertness of PI limits its direct binding ability to bone tissue. Therefore, improving the bioactivity of PI to induce cellular responses and bone regeneration is one of the challenges facing the biomedical application of PI in orthopedic fields.

[0003] Hydroxyapatite (HAp), as a major inorganic component of bone tissue, can enhance the bioactivity of materials, but its brittleness can easily lead to a decline in the mechanical properties of composite materials. Copper oxide (CuO) nanoparticles have the potential for antibacterial activity and promoting osteogenic differentiation, but their single addition may lead to aggregation problems, affecting the uniformity of the material. In existing technologies, single fillers (such as carbon fiber and HAp) are often used to reinforce PI, but this results in problems such as weak interfacial bonding and limited functionality. Summary of the Invention

[0004] To address the aforementioned technical problems, an antibacterial polyimide composite material and its preparation method are provided. The composite material of this invention exhibits good antibacterial properties and bioactivity while maintaining mechanical properties.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] A method for preparing an antibacterial polyimide composite material includes the following steps:

[0007] S1. Under continuous stirring, an inorganic antibacterial agent, macromolecular chain sugars, and water-soluble calcium are added to water to form a dispersion. The temperature is controlled within the range of 30-65℃ as a phosphate solution is added dropwise to the dispersion. Simultaneously, a precipitant solution is added dropwise, and the pH value of the system is maintained within the range of 9.5-11.5 under pH monitoring. After the phosphate solution is completely added, the pH value of the system is adjusted to maintain within the range of 9.5-11.5. The mixture is then aged, and solid-liquid separation is performed. The solid portion is washed, dried, and calcined to obtain a hydroxyapatite@inorganic antibacterial agent complex. The inorganic antibacterial agent is uniformly dispersed in water and captured and bonded by the hydroxyl groups on the macromolecular chains of the sugars. Free calcium ions and phosphate groups in the dispersion are precipitated on the surface of the inorganic antibacterial agent by the precipitant. Simultaneously, the macromolecular chain sugars act as a dispersant to control the formation of small-particle precipitates.

[0008] The dipping solution comprises the following substances in 100% by mass percentage: 0.1%-10% of the hydroxyapatite@inorganic antibacterial agent complex, 0.5%-5% of polyvinylpyrrolidone, 0.05-0.2% of aminosilane coupling agent, and the balance being an aqueous alcohol solution;

[0009] S2. Immerse the porous polyimide part into the impregnation solution, vacuum impregnate, drain, and dry to obtain the antibacterial polyimide composite material.

[0010] Furthermore, the inorganic antibacterial agent is selected from nano copper oxide and / or nano zinc oxide, and the average particle size of the inorganic antibacterial agent is less than 200 nm; the macromolecular chain sugar is selected from dextran or chitosan oligosaccharide, and its weight average molecular weight is less than 50,000 g / mol.

[0011] Furthermore, the water-soluble calcium is selected from calcium chloride and / or calcium nitrate; the phosphate in the phosphate solution is selected from one or more of diammonium hydrogen phosphate, disodium hydrogen phosphate, ammonium dihydrogen phosphate, and sodium dihydrogen phosphate; the precipitant is a 2-5 mol / L sodium hydroxide solution. If the concentration is less than 2M, the volume of precipitant added will be too large, severely diluting the reaction system and reducing the product concentration. If the concentration is greater than 5M, it will easily lead to local over-alkaliness, generating impurity phases and causing particle agglomeration.

[0012] Furthermore, the water-soluble calcium in the dispersion and the phosphate in the phosphate solution are prepared and added according to a calcium-to-phosphorus molar ratio of 1.67; the amount of the sugar is 0.005%-0.02% of the molar amount of the water-soluble calcium; and the amount of the inorganic antibacterial agent is 2%-15% of the mass of the generated hydroxyapatite.

[0013] Furthermore, after the inorganic antibacterial agent described in S1 is added to water, it is subjected to a combination of mechanical stirring and ultrasonic dispersion. The mechanical stirring speed is 800-2000 rpm, the ultrasonic dispersion frequency is 80-120 kHz, and after dispersion for 20-50 minutes, macromolecular chain sugars and water-soluble calcium are added. After dissolving and dispersing evenly, the ultrasonic dispersion is removed.

[0014] Furthermore, the pH value of the system is maintained in the range of 10-11.5 during the reaction process using a pH meter; the aging temperature is 50-60℃ and the aging time is 12-24h; the calcination temperature is 300-900℃ and the calcination time is 1-5h.

[0015] Furthermore, the K value of the polyvinylpyrrolidone is in the range of 10-70, and typical substances that can be selected include PVPK15, PVP K17, PVP K25, PVP K30, and PVP K60; the aminosilane coupling agent is selected from one or more of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane.

[0016] Furthermore, the vacuum impregnation described in S2 involves placing the solution in a vacuum drying oven, evacuating it to -90 kPa, and maintaining the pressure for 30-120 minutes to allow the negative pressure difference to drive the particles in the solution into the deep pores.

[0017] Furthermore, the porous polyimide part is prepared by using PI fine powder with a particle size of less than 300 mesh to form PI parts by cold pressing and sintering, and then immersing it in concentrated sulfuric acid with a concentration of at least 70wt% for sulfonation reaction for 60-240 minutes.

[0018] In another aspect, the present invention provides an antibacterial polyimide composite material prepared by the above preparation method, the structure of which is a sulfonated porous polyimide supported on hydroxyapatite@inorganic antibacterial agent composite, wherein the loading of the composite is 0.2wt%-2wt%.

[0019] Beneficial technical effects:

[0020] This application synthesizes nano-hydroxyapatite to form a complex on the surface of an inorganic antibacterial agent, and then disperses it in a dispersion and attaches it to the surface and pores of sulfonated porous PI, so that the material has good biocompatibility while having certain antibacterial properties. The sulfonated porous PI structure used in this application has better surface adhesion and diffusion properties, thereby inducing cell reactions. The hydroxyapatite@inorganic antibacterial agent complex on the surface and pores of sulfonated porous PI gives the porous PI a larger specific surface area and higher adsorption activity, preventing bacterial adhesion while adsorbing more proteins that form biofilms. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Unless otherwise specifically stated, the numerical values ​​set forth in these embodiments do not limit the scope of the invention. Techniques and methods known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques and methods should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that values ​​expressed, for example, as "within the range of ab" or "between the range of ab," do not include the endpoint values ​​a and b; values ​​expressed as "for ab," "is ab," or "ab" include the endpoint values ​​a and b.

[0023] Experimental methods not specified in the following examples are generally performed according to national standards; if there is no corresponding national standard, they are performed according to general standard requirements or general methods.

[0024] The polyimide used below is model JHPI-1300, and the manufacturer is Shandong Junhao High Performance Polymer Co., Ltd.

[0025] Preparation Example 1

[0026] This case study describes the preparation of porous polyimide, which includes the following steps:

[0027] (1) 200-300 mesh polyimide fine powder is made into parts by cold pressing sintering method. Cold pressing sintering method parameters: the fine powder is placed in the mold and pressed to 5MPa at room temperature and held for 10min, and then sintered at 330℃ for 10min to obtain PI parts with Φ10×thickness 5mm.

[0028] (2) After sanding the surface of the PI part with sandpaper, it is cleaned with ethanol and water to remove impurities. Then it is immersed in concentrated sulfuric acid with a concentration of 98wt% for sulfonation reaction for 60 minutes. After taking it out, it is washed with water until neutral to obtain porous PI.

[0029] Preparation Example 2

[0030] This case study describes the preparation of porous polyimide, which includes the following steps:

[0031] (1) 200-300 mesh polyimide fine powder is made into parts by cold pressing sintering method. Cold pressing sintering method parameters: the fine powder is placed in the mold and pressed to 8MPa at room temperature and held for 6min, and then sintered at 320℃ for 40min to obtain PI parts with Φ10×thickness 5mm.

[0032] (2) After sanding the surface of the PI part with sandpaper, it is cleaned with ethanol and water to remove impurities. Then it is immersed in concentrated sulfuric acid with a concentration of 98wt% for sulfonation reaction for 80 minutes. After taking it out, it is washed with water until neutral to obtain porous PI.

[0033] Preparation Example 3

[0034] This case study describes the preparation of porous polyimide, which includes the following steps:

[0035] (1) 200-300 mesh polyimide fine powder is made into parts by cold pressing sintering method. Cold pressing sintering method parameters: the fine powder is placed in the mold and pressed to 10MPa at room temperature and held for 10min, and then sintered at 340℃ for 20min to obtain PI parts with Φ10×thickness 5mm.

[0036] (2) After sanding the surface of the PI part with sandpaper, it is cleaned with ethanol and water to remove impurities. Then it is immersed in concentrated sulfuric acid with a concentration of 98wt% for sulfonation reaction for 70 minutes. After taking it out, it is washed with water until neutral to obtain porous PI.

[0037] Example 1

[0038] A method for preparing an antibacterial polyimide composite material includes the following steps:

[0039] S1. Under continuous stirring at 1000 rpm, nano-copper oxide (average particle size less than 100 nm) was added to 100 mL of pure water for mechanical dispersion and ultrasonic dispersion (ultrasonic frequency 100 kHz) for 40 min. Then, dextran (weight average molecular weight 4000 g / mol) and calcium nitrate were added and stirred until a uniform dispersion was formed.

[0040] The dispersion contains 1 g / L of nano-copper oxide, 0.5 g / L of dextran, and 1.0 mol / L of calcium nitrate;

[0041] The system temperature was controlled at 60℃. 100 mL of 0.6 mol / L diammonium hydrogen phosphate aqueous solution was added dropwise to the dispersion. At the same time, 3.0 mol / L sodium hydroxide aqueous solution was added dropwise and the pH of the system was adjusted to 10.5 under the monitoring of a pH meter. After the diammonium hydrogen phosphate aqueous solution was completely added, the pH of the system was adjusted to 10.5. The mixture was aged at 60℃ for 12 h. Solid-liquid separation was performed. The solid part was washed with water and alcohol multiple times until neutral. It was dried at 80℃ for 12 h, ground, and then calcined at 500℃ for 2 h. The mixture was then ground with a nano-sand mill until the average particle size was less than 300 nm to obtain the hydroxyapatite@copper oxide composite.

[0042] Prepare an impregnation solution comprising the following 100% by mass percentages: 1% of the hydroxyapatite@copper oxide complex, 1% of PVP K30, 0.05% of γ-aminopropyltriethoxysilane, and the balance being an aqueous ethanol solution (of which anhydrous ethanol accounts for 30 wt%).

[0043] S2. Immerse 0.56g of porous PI from Preparation Example 1 into 20g of the above-mentioned impregnation solution, place it in a vacuum drying oven, vacuum to -90 kPa and maintain pressure for 60min, remove and drain, and dry at 80℃ to obtain antibacterial polyimide composite material (weight gain 0.11g).

[0044] Example 2

[0045] A method for preparing an antibacterial polyimide composite material includes the following steps:

[0046] S1. Under continuous stirring at 1500 rpm, nano copper oxide (average particle size less than 100 nm) was added to 100 mL of pure water for mechanical stirring and dispersion, while ultrasonic dispersion (ultrasonic frequency 80 kHz) was performed for 30 min. Then, dextran with a weight average molecular weight of 9000 g / mol and calcium nitrate were added and stirred evenly to form a dispersion.

[0047] The dispersion contains 1 g / L of nano-copper oxide, 0.8 g / L of dextran, and 1.0 mol / L of calcium nitrate;

[0048] The system temperature was controlled at 60℃. 100 mL of 0.6 mol / L diammonium hydrogen phosphate aqueous solution was added dropwise to the dispersion. At the same time, 2.5 mol / L sodium hydroxide aqueous solution was added dropwise and the pH of the system was adjusted to 10.8 under pH monitoring. After the diammonium hydrogen phosphate aqueous solution was completely added, the pH of the system was adjusted to 10.8. The mixture was aged at 60℃ for 12 h. Solid-liquid separation was performed. The solid fraction was washed with water and alcohol multiple times until neutral. It was dried at 80℃ for 12 h, ground, and then calcined at 600℃ for 1 h. The mixture was then ground using a nano-grinding mill until the average particle size was less than 300 nm to obtain the hydroxyapatite@copper oxide composite.

[0049] Prepare an impregnation solution comprising the following 100% by mass percentages: 1.3% of the hydroxyapatite@copper oxide complex, 2% of PVP K25, 0.1% of γ-aminopropyltriethoxysilane, and the balance being an aqueous ethanol solution (of which anhydrous ethanol accounts for 20 wt%).

[0050] S2. Immerse 0.56g of porous PI from Preparation Example 2 into 20g of the above-mentioned impregnation solution, place it in a vacuum drying oven, vacuum to -90 kPa and maintain pressure for 40min, remove and drain, and dry at 80℃ to obtain antibacterial polyimide composite material (weight gain 0.21g).

[0051] Example 3

[0052] A method for preparing an antibacterial polyimide composite material includes the following steps:

[0053] S1. Under continuous stirring at 2000 rpm, nano copper oxide (average particle size less than 100 nm) was added to 100 mL of pure water for mechanical stirring and dispersion, while simultaneously being ultrasonically dispersed (ultrasonic frequency 80 kHz). After dispersion for 30 min, dextran with a weight average molecular weight of 10000 g / mol and calcium nitrate were added and stirred evenly to form a dispersion.

[0054] The dispersion contains 1.1 g / L of nano-copper oxide, 1.2 g / L of dextran, and 1.0 mol / L of calcium nitrate.

[0055] The system temperature was controlled at 60℃. 100 mL of 0.6 mol / L diammonium hydrogen phosphate aqueous solution was added dropwise to the dispersion. At the same time, 4.0 mol / L sodium hydroxide aqueous solution was added dropwise and the pH of the system was adjusted to 11 under the monitoring of a pH meter. After the diammonium hydrogen phosphate aqueous solution was completely added, the pH of the system was adjusted to 11. The mixture was aged at 60℃ for 12 h. Solid-liquid separation was performed. The solid part was washed with water and alcohol multiple times until neutral. It was dried at 80℃ for 12 h, ground, and then calcined at 400℃ for 3 h. The mixture was then ground with a nano-sand mill until the average particle size was less than 300 nm to obtain the hydroxyapatite@copper oxide composite.

[0056] Prepare an impregnation solution comprising the following 100% by mass percentages: 1.8% of the hydroxyapatite@copper oxide complex, 1.5% of PVP K15, 0.15% of γ-aminopropyltriethoxysilane, and the balance being an aqueous ethanol solution (of which anhydrous ethanol accounts for 10 wt%).

[0057] S2. Immerse 0.56g of porous PI from Preparation Example 3 into 20g of the above-mentioned impregnation solution, place it in a vacuum drying oven, vacuum to -90 kPa and maintain pressure for 100min, remove and drain, and dry at 80℃ to obtain antibacterial polyimide composite material (weight gain 0.28g).

[0058] Comparative Example 1

[0059] The preparation of the composite material in this case is the same as in Example 1, except that step S1 was not performed, and the hydroxyapatite@copper oxide composite was replaced with nano-copper oxide in the coating solution.

[0060] Comparative Example 2

[0061] The preparation of the composite material in this case is the same as in Example 1, except that nano-copper oxide was not added in step S1, hydroxyapatite was synthesized, and hydroxyapatite replaced the hydroxyapatite@copper oxide composite in the dipping solution.

[0062] Comparative Example 3

[0063] The composite material in this case was prepared as follows: 1g of nano copper oxide (average particle size less than 100nm), 1g of nano hydroxyapatite (average particle size less than 200nm) and 98g of polyamic acid solution were mechanically mixed to form an impregnation solution, which was coated on the surface of the PI part in step (1) of preparation example 1. After thermal imidization (heating from room temperature to 80°C at a rate of 80°C / h and holding for 1h, heating from 80°C to 150°C at a rate of 60°C / h and holding for 2h, heating from 150°C to 260°C at a rate of 60°C / h and holding for 1h, heating from 260°C to 320°C at a rate of 60°C / h and holding for 2h), a film was formed (the porous structure of preparation example 1 was not used).

[0064] Test case

[0065] 1. In vitro antibacterial activity

[0066] In vitro antibacterial activity was tested using Staphylococcus aureus and Escherichia coli via bacterial counting. Samples were sterilized by ultraviolet irradiation for 24 hours, after which a concentration of 10 was obtained. 7 A bacterial solution of CFU / mL was dropped onto the sample surface (100 μL / well). After incubating the bacteria on the sample (at 37°C) for 24 hours, the sample was washed with PBS to remove unattached bacteria. Then, the bacteria adhering to the sample were separated into PBS (3 mL) by ultrasonic vibration (150 W, 50 Hz) for 5 min. The separated bacteria were collected and serially diluted into bacterial suspensions. Then, 10 μL of each suspension was transferred to an agar plate and incubated at 37°C for 24 hours. The bacterial colony count was determined, and the antibacterial rate was calculated. The results are shown in Table 1.

[0067] 2. Cell proliferation

[0068] BMSC proliferation on the specimens was assessed using the MTT assay. Cells were cultured on the specimens (cell density: 2 × 10⁻⁶). 4 In 24-well plates, after culturing for 1 and 7 days, the culture medium was removed and replaced with 400 μL α-MEM and 100 μL MTT solution for 4 hours; additionally, 500 μL dimethyl sulfoxide (DMSO) was used to replace the culture medium for 30 minutes. The optical density (OD) of the cells on the specimens was measured at 490 nm using a microplate reader. The results are shown in Table 1.

[0069] 3. Protein adsorption

[0070] The adsorption capacity of proteins for samples was determined using bovine serum albumin (BSA). Briefly, samples were placed in 24-well plates, and BSA solution (1 mL, 100 μg / mL) was introduced onto the samples, followed by incubation for 3 hours. Afterward, the samples were removed and washed twice with phosphate-buffered saline (PBS) to remove unabsorbed proteins. Sodium dodecyl sulfate (2%, SDS) solution was then used to elute the proteins adsorbed on the sample surface. The solutions were collected, and the protein concentration in the SDS solution was determined by measuring absorbance at 562 nm using a BCA protein assay kit (Beyotime Biotechnology Co., Ltd., Shanghai). The results are shown in Table 1.

[0071] Table 1 Results of each case

[0072]

[0073] As shown in Table 1, the porous PI prepared in Example 1 has virtually no antibacterial properties, despite the formation of a porous surface. However, due to the inertness of the PI surface, the cell proliferation OD value and protein adsorption are both low. Comparative Examples 1 and 2 contain only one substance from the hydroxyapatite@copper oxide complex, and their contribution to the cell proliferation OD value and protein adsorption is poor when combined with porous PI. Comparative Example 3 uses hydroxyapatite and nano-copper oxide mixed in a polyamic acid solution. Due to the larger amount of both compared to Example 1, the antibacterial rate is higher, but there is uneven dispersion, so the cell proliferation OD value and protein adsorption are slightly lower than those of Example 1. In this application, the synthesized hydroxyapatite@copper oxide complex is formed into a dispersion and combined with porous PI. This achieves bacterial inhibition with a low loading of composite antibacterial agent while ensuring the biocompatibility of PI. The material of this invention can provide both antibacterial and osteogenic induction properties, aiming to promote bone integration while being antibacterial, and is suitable for the field of bone integration implants.

[0074] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing an antibacterial polyimide composite material, characterized in that, Includes the following steps: S1. Under continuous stirring, an inorganic antibacterial agent, macromolecular chain sugars, and water-soluble calcium are added to water to form a dispersion. A phosphate solution is added dropwise to the dispersion while maintaining the temperature within the range of 30-65℃. The water-soluble calcium in the dispersion and the phosphate in the phosphate solution are added according to a calcium-to-phosphorus molar ratio of 1.

67. Simultaneously, a precipitant solution is added dropwise, and the pH of the system is maintained within the range of 9.5-11.5 under pH meter monitoring. After the phosphate solution is completely added, the pH of the system is adjusted to maintain within the range of 9.5-11.

5. The mixture is then aged, and solid-liquid separation is performed. The solid portion is washed, dried, and calcined to obtain a hydroxyapatite@inorganic antibacterial agent complex. The inorganic antibacterial agent is selected from nano-copper oxide and / or nano-zinc oxide, and the average particle size of the inorganic antibacterial agent is less than 200 nm; the macromolecular chain sugar is selected from dextran or chitosan oligosaccharide, and its weight-average molecular weight is less than 50,000 g / mol; the amount of the macromolecular chain sugar is 0.005%-0.02% of the molar amount of water-soluble calcium; the amount of the inorganic antibacterial agent is 2%-15% of the mass of the generated hydroxyapatite; The inorganic antibacterial agent is uniformly dispersed in water and captured and bonded by the hydroxyl groups on the macromolecular chains of sugar substances. The free calcium ions and phosphate ions in the dispersion are precipitated on the surface of the inorganic antibacterial agent by the precipitant. At the same time, the macromolecular chain sugar substances act as a dispersant to control the formation of precipitates. The dipping solution comprises the following substances in 100% by mass percentage: 0.1%-10% of the hydroxyapatite@inorganic antibacterial agent complex, 0.5%-5% of polyvinylpyrrolidone, 0.05-0.2% of aminosilane coupling agent, and the balance being an aqueous alcohol solution; S2. Immerse the porous polyimide part into the dip coating solution, vacuum impregnate, drain, and dry to obtain an antibacterial polyimide composite material. The porous polyimide part is prepared by using polyimide fine powder with a particle size of less than 300 mesh to form a polyimide part by cold pressing and sintering, and then immersing it in concentrated sulfuric acid with a concentration of at least 70wt% for sulfonation reaction for 60-240 minutes.

2. The method for preparing an antibacterial polyimide composite material according to claim 1, characterized in that, The water-soluble calcium is selected from calcium chloride and / or calcium nitrate; the phosphate in the phosphate solution is selected from one or more of diammonium hydrogen phosphate, disodium hydrogen phosphate, ammonium dihydrogen phosphate, and sodium dihydrogen phosphate; the precipitant is a 2-5 mol / L sodium hydroxide solution.

3. The method for preparing an antibacterial polyimide composite material according to claim 1, characterized in that, The inorganic antibacterial agent described in S1 is added to water and then mechanically stirred and ultrasonically dispersed. The mechanical stirring speed is 800-2000 rpm, and the ultrasonic dispersion frequency is 80-120 kHz. After dispersing for 20-50 minutes, macromolecular chain sugars and water-soluble calcium are added. After dissolving and dispersing evenly, the ultrasonic dispersion is removed.

4. The method for preparing an antibacterial polyimide composite material according to claim 1, characterized in that, The pH meter was used to monitor the pH value of the system during the reaction process, maintaining it within the range of 10-11.5; the aging temperature was 50-60℃ and the aging time was 12-24h; the calcination temperature was 300-900℃ and the calcination time was 1-5h.

5. The method for preparing an antibacterial polyimide composite material according to claim 1, characterized in that, The K value of the polyvinylpyrrolidone is in the range of 10-70; the aminosilane coupling agent is selected from one or more of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane.

6. The method for preparing an antibacterial polyimide composite material according to claim 1, characterized in that, The vacuum impregnation described in S2 involves placing the sample in a vacuum drying oven, evacuating it to -90 kPa, and maintaining the pressure for 30-120 minutes for penetration.

Images