阅读说明：本技术 一种具有仿生电活性涂层钛植入体及其制备方法 (Titanium implant with bionic electroactive coating and preparation method thereof ) 是由 张学慧 邓旭亮 白云洋 孙晓雯 王博 于 2020-12-29 设计创作，主要内容包括：本发明涉及一种具有仿生电活性涂层钛植入体及制备方法,其解决了现有钛植入体涂层的生物活性不足或对人体有害的技术问题,本发明提供的具有仿生电活性涂层的钛植入体,其设有涂层,涂层含有填料和高分子基体,填料为压电陶瓷纳米颗粒,基体为铁电高分子聚合物,压电陶瓷颗粒均匀分散在铁电聚合物中,本发明同时提供了其制备方法,使得仿生电活性涂层可与钛表面牢固结合。本发明可用于钛植入体材料表面功能化设计与制备领域。(The invention relates to a titanium implant with a bionic electroactive coating and a preparation method thereof, which solve the technical problems of insufficient bioactivity of the coating of the conventional titanium implant or harm to human bodies. The method can be used in the field of surface functional design and preparation of titanium implant materials.)

1. A titanium implant with a bionic electroactive coating is provided with a coating, wherein the coating contains a filler and a matrix, and the titanium implant is characterized in that the filler is piezoelectric ceramic particles, the matrix is a ferroelectric high polymer, and the piezoelectric ceramic particles are uniformly dispersed in the ferroelectric high polymer; the volume fraction of the piezoelectric ceramic particles in the matrix is 5-15%; the diameter of the piezoelectric ceramic particles is 50 nm-500 nm.

2. The titanium implant with biomimetic electroactive coating according to claim 1, wherein the ferroelectric polymer is one or more of PVDF, P (VDF-TrFE), and PVDF derivative.

3. The titanium implant with biomimetic electroactive coating of claim 1, wherein the piezoelectric ceramic particles comprise one or more of barium titanate, barium strontium titanate, bismuth ferrite, potassium sodium niobate, lithium niobate.

4. A method for preparing a titanium implant with a bionic electroactive coating is characterized by comprising the following steps:

(1) the medical titanium implant material is subjected to one or more of laser, micro-arc oxidation, machining, sand blasting and acid etching treatment, and a rough porous structure is generated on the surface of the medical titanium material;

(2) taking piezoelectric ceramic particles, dispersing the piezoelectric ceramic particles in an organic solvent by ultrasonic oscillation, and stirring by adopting ultrasonic oscillation to obtain a ceramic particle dispersion liquid;

(3) weighing a ferroelectric high molecular polymer, and adding the ferroelectric high molecular polymer into an organic solvent to obtain a polymer solution;

(4) adding the suspension obtained in the step (2) into the polymer solution obtained in the step (3), and stirring to uniformly disperse the ceramic particle filler in the polymer matrix to obtain a mixed solution;

(5) uniformly coating the mixed solution obtained in the step (4) on the surface of the medical titanium material obtained in the step (1), firmly combining the mixed solution with the rough porous structure of the surface layer of the titanium material, and drying to obtain the titanium material with the ferroelectric compound coating;

(6) and (4) carrying out corona polarization treatment on the dried titanium material with the coating obtained in the step (5) to obtain the titanium implant with the bionic electroactive coating.

5. The method for preparing a titanium implant with a biomimetic electroactive coating according to claim 5, wherein in the step (6), the polarization field strength is 0.1kV/mm to 10kV/mm, the polarization time is 1min to 60min, the polarization medium is one of air and methyl silicone oil, and the polarization temperature is 25 ℃ to 100 ℃.

Technical Field

The invention relates to a biomedical implant material, in particular to a titanium implant with a bionic electroactive coating and a preparation method thereof.

Background

Medical metal titanium (Ti) and its alloys are widely used in the field of medical implants due to their good chemical stability and excellent biocompatibility. However, the titanium implant surface lacks biological activity, and is only simply mechanically embedded with bone tissue, which is easy to cause the unsatisfactory bone combination effect and further cause the implant to loosen, infect and fall off.

Researches show that the improvement of the surface activity of titanium and alloys thereof can promote osseointegration, and scholars at home and abroad try a plurality of physical and chemical methods to improve the surface activity of metallic titanium and alloys thereof, including surface modification and activated coating. Surface modification methods such as sand blasting, acid etching, micro-arc oxidation, plasma spraying and the like lack biological activity similar to natural bone tissues, and the bone union effect is not ideal enough. The ideal medical implant material surface provides a good osteoinduction microenvironment for new bone formation, improves the new bone formation and bone combination effect, and has good bone combination stability. Nowadays, electroactive materials are widely concerned by researchers, and the materials can realize bionic electroactive through design and processing and provide a proper electrical microenvironment for cell function differentiation and new osteogenesis. Therefore, the research on the bionic electroactive coating which can simulate the piezoelectric property of natural bone tissues, has strong binding force with a titanium substrate and high stability becomes a problem to be solved and explored urgently in the field of medical implant materials.

The Chinese patent application with publication number CN109179356A discloses a method for preparing a hydroxyapatite coating on the surface of titanium or titanium alloy, which comprises the steps of firstly immersing an implant into an aqueous solution containing calcium ions, providing phosphorus element steam by using a phosphorus cracker, providing the phosphorus element steam and ozone to collide with the surface of a matrix under the vacuum condition, and controlling the deposition rate of phosphorus element and oxygen element components to ensure that the reaction of the component elements only occurs on the matrix, thereby promoting the surface of the implant to generate a low-crystalline bioactive hydroxyapatite coating. The coating mainly improves the bioactivity of the titanium or titanium alloy surface by inducing new bone formation by hydroxyapatite, but the hydroxyapatite can be gradually degraded after being implanted into a human body for a long time, the coating falls off, and the bioactivity is reduced.

The Chinese patent application with publication number CN1785439A discloses an active biological piezoelectric ceramic coating and a method for preparing the coating on the surface of a titanium substrate, which mainly form a porous oxide film layer by a micro-arc oxidation technology, and then prepare a composite coating of fluorhydroxyapatite and barium titanate (FHABT) on the surface of a sample by an electrophoretic deposition technology to improve the biocompatibility and the biological activity of the composite coating. However, with the degradation of the hydroxyapatite in the coating, the barium titanate particles can be released into the human body, and potential harm can be caused to the human body because the barium titanate particles cannot be degraded in the human body.

The Chinese patent application with publication number CN108079381A discloses a preparation method of a medical titanium alloy surface bio-piezoelectric composite coating, which comprises the steps of firstly generating a titanium dioxide coating with a compact inner layer and a porous surface layer on the surface of a titanium alloy substrate in situ by adopting a micro-arc oxidation technology, then generating a barium titanate coating by adopting a hydrothermal chemical method to perform in-situ reaction on the titanium dioxide coating, and finally filling holes on the surface of the polarized coating, namely forming the composite coating with the bio-piezoelectric property on the surface of the medical titanium alloy. The coating prepared by the invention has a compact inner layer, is well combined with a matrix, has high stability, and can effectively prevent harmful metal ions from dissolving out to body fluid; the barium titanate coating with the porous surface layer can generate a piezoelectric effect, promote local blood circulation and further accelerate bone repair; the holes are filled with substances or antibacterial drugs which are beneficial to the growth of early bone tissues, and meanwhile, the rough surface is beneficial to the adhesion and proliferation of cells, so that the metal material has good biocompatibility and bioactivity. Although the coating prepared by the method has the advantages of compact inner layer, good combination with a matrix and high stability, the preparation method of the coating is complex, the process is complicated, and the coating is not easy to popularize.

Disclosure of Invention

The invention provides a titanium implant with a firmly combined bionic electroactive coating and a coating harmless to a human body and a preparation method thereof, aiming at the technical problems of insufficient bioactivity or harm to the human body of the existing titanium implant coating.

Therefore, the invention provides a titanium implant with a bionic electroactive coating, which is provided with a coating, wherein the coating contains a filler and a matrix, the filler is piezoelectric ceramic particles, the matrix is a ferroelectric high polymer, and the piezoelectric ceramic particles are uniformly dispersed in the ferroelectric high polymer; the volume fraction of the piezoelectric ceramic particles in the matrix is 5-15%; the diameter of the piezoelectric ceramic particles is 50 nm-500 nm.

Preferably, the ferroelectric polymer is one or more of PVDF, P (VDF-TrFE), and PVDF derivative.

Preferably, the piezoelectric ceramic particles comprise one or more of barium titanate, barium strontium titanate, bismuth ferrite, potassium sodium niobate and lithium niobate.

The invention also provides a preparation method of the titanium implant with the bionic electroactive coating, which comprises the following steps: (1) the medical titanium implant material is subjected to one or more of laser, micro-arc oxidation, machining, sand blasting and acid etching treatment, and a rough porous structure is generated on the surface of the medical titanium material; (2) taking piezoelectric ceramic particles, dispersing the piezoelectric ceramic particles in an organic solvent by ultrasonic oscillation, and stirring by adopting ultrasonic oscillation to obtain a ceramic particle dispersion liquid; (3) weighing a ferroelectric high molecular polymer, and adding the ferroelectric high molecular polymer into an organic solvent to obtain a polymer solution; (4) adding the suspension obtained in the step (2) into the polymer solution obtained in the step (3), and stirring to uniformly disperse the ceramic particle filler in the polymer matrix to obtain a mixed solution; (5) uniformly coating the mixed solution obtained in the step (4) on the surface of the medical titanium material obtained in the step (1), firmly combining the mixed solution with the rough porous structure of the surface layer of the titanium material, and drying to obtain the titanium material with the ferroelectric compound coating; (6) and (4) carrying out corona polarization treatment on the dried titanium material with the coating obtained in the step (5) to obtain the titanium implant with the bionic electroactive coating.

Preferably, in the step (6), the polarization field strength is 0.1 kV/mm-10 kV/mm, the polarization time is 1 min-60 min, the polarization medium is one of air and methyl silicone oil, and the polarization temperature is 25-100 ℃.

The invention has the following beneficial effects:

the inventor researches and shows that the rough porous structure of the titanium surface is a key factor determining the bonding effect of the coating, and the invention performs roughening treatment on the titanium surface in order to realize firm bonding of the electroactive coating and the titanium surface, avoid insufficient bonding of the coating and enhance the long-term stability of the bionic electroactive coating titanium implant.

The inventor researches and shows that the low piezoelectric phase barium titanate content in the titanium surface coating can cause the poor piezoelectric performance of the composite material, and further cause the insufficient bioactivity of the composite material. In order to make the medical titanium implant material of the composite coating obtain better biological activity and achieve the electrical activity of bionic magnitude, the inventor adopts polyvinylidene fluoride (PVDF) and copolymer thereof, such as polyvinylidene fluoride trifluoroethylene P (VDF-TrFE), to dope barium titanate (BaTiO)₃BTO) nanoparticles to prepare a mixed solution and to achieve biomimetic-magnitude electrical activity by optimizing the volume fraction of the nano barium titanate particles.

Finally, the mixed solution of the nano barium titanate particles with the optimal volume fraction is used for modifying the surface coating of the titanium implant material. The difference of the coating combination stability and the rabbit bone combination promoting effect after the bionic electroactive coating and the polylactic acid PLLA coating are implanted into a body is compared to verify the bionic electroactive BaTiO₃Feasibility and effectiveness of/P (VDF-TrFE) nanocomposites as implant coating materials.

(1) The invention firstly adopts one or more technologies of laser, mechanical processing, micro-arc oxidation, sand blasting, acid etching and the like to form a rough porous structure on the surface of the medical titanium implant material, on the basis, a casting method is adopted to compound the bionic electroactive nano coating, and then polarization treatment is carried out, so that the coating has the electrical property of bionic magnitude, and the bionic electroactive coating structure which has excellent combination stability and promotes osseointegration is formed on the surface of the medical titanium implant material.

(2) The bionic electroactive coating compounded by the invention belongs to a non-degradable material, and the material has excellent coating stability after being implanted into a body, can keep long-term stable electrical characteristics, and can avoid the problems of ion precipitation and absorption by a human body caused by material degradation.

(3) The bionic electroactive coating can reach the bionic magnitude due to the inherent ferroelectric property and polarization treatment, and the controllable osseointegration effect can be realized by the established bionic electric microenvironment.

(4) The medical titanium implant material of the bionic electroactive coating prepared by the invention has excellent osseointegration effect.

(5) The preparation process is simple, and can be industrially produced in batch and popularized and applied.

In conclusion, the medical titanium implant material with the bionic electroactive coating provided by the invention has excellent performance and strong operability in basic experimental effect and clinical application and popularization, is firmly fixed with a titanium matrix in an osseointegration process, has excellent stability, forms good biocompatibility with a host, provides a suitable bionic-magnitude electrical microenvironment for new bone generation, presents a good osseointegration effect, can keep long-term stable electrical characteristics, realizes accurate and controllable osseointegration effect, and improves the aspects of induced bone formation suitability, clinical operation, prognosis and the like.

Drawings

FIG. 1 is a photograph of a medical titanium implant material with a biomimetic electroactive coating according to embodiment 1 of the present invention;

fig. 2A, fig. 2B, fig. 2C, fig. 2D, fig. 2E, fig. 2F, fig. 2G, fig. 2H, fig. 2I, fig. 2J, fig. 2K, and fig. 2L respectively show the results of EDS spectroscopy analysis of pure titanium surface morphology (45 times), pure titanium surface (200 times), pure titanium surface (5000 times), pure titanium surface EDS spectroscopy analysis, PLLA coating surface morphology (45 times), PLLA coating surface (200 times), PLLA coating surface (5000 times), PLLA coating surface EDS spectroscopy analysis, electroactive coating surface morphology (45 times), electroactive coating surface (200 times), electroactive coating surface (5000 times), and electroactive coating surface EDS spectroscopy analysis, according to example 1 of the present invention.

Fig. 3A, fig. 3B, and fig. 3C are respectively the results of testing the surface roughness (a), hydrophilicity and hydrophobicity (B), piezoelectric constant, and electrical stability (C) of the bionic electroactive coating on the surface of the titanium implant according to embodiment 1 of the present invention;

fig. 4A, fig. 4B, fig. 4C, fig. 4D and fig. 4E are respectively a hypoploid, a magnified partial view, a hypoploid, a magnified partial view and a bone union ratio detection result of a hard tissue section 4 weeks after the implantation of the PLLA coated titanium implant material into the rabbit tibial defect, and a hard tissue section 4 weeks after the implantation of the biomimetic electroactive coated titanium implant material into the rabbit tibial defect according to example 1 of the present invention.

Fig. 5A and 5B are a hard tissue slice test result 12 weeks after the PLLA coated titanium implant material is implanted into rabbit tibial bone defect surgery and a hard tissue slice test result 12 weeks after the bionic electroactive coated titanium implant material is implanted into rabbit tibial bone defect surgery according to example 1 of the present invention, respectively.

Detailed Description

The present invention will be further described with reference to the following examples.

Example 1

(1) Firstly, using SiO to make conventional medical pure titanium cylinder₂The granules were grit blasted at a pressure of 0.4MPa and then treated with 10% H₂SO₄Acid etching with 10% HCl mixed solution at 60 deg.C for 30 min;

(2) putting the nano barium titanate particles into dopamine aqueous solution, heating and stirring in a water bath at 60 ℃ for 12 hours, and centrifugally drying to obtain barium titanate nano particle filler;

(3) taking a proper amount of the barium titanate nano particle filler (BaTiO) prepared in the step (2)₃) Dispersing in 3ml of organic solvent (such as DMF), and stirring for 3 hours by adopting stirring and ultrasonic oscillation to obtain barium titanate particle filler dispersion liquid;

(4) dispersing 1g polymer (such as P (VDF-TrFE)) powder in 7ml organic solvent (such as DMF), stirring for 3 hr to completely dissolve to obtain polymer (such as P (VDF-TrFE)) solution;

(5) mixing the barium titanate particle filler dispersion liquid formed in the step (3) and the polymer (such as P (VDF-TrFE)) solution formed in the step (4), and stirring for 24h to obtain particle filler (BaTiO)₃) Uniformly dispersing the mixed solution;

(6) adding a proper amount of polylactic acid and a copolymer (PLLA) thereof into 10ml of trifluoroethanol, and stirring for 24h to obtain a mixed solution in which polylactic acid and a copolymer filler (PLLA) thereof are uniformly dispersed;

(7) respectively uniformly coating the mixed liquid obtained in the step (5) and the step (6) on the surface of the titanium column subjected to sand blasting-acid etching treatment, and drying at the temperature of 80 ℃ for 2 hours to completely volatilize the solvent and obtain a uniform coating compounded on the surface of the titanium column;

(8) placing the titanium column with the composite uniform coating prepared in the step (7) on a sample table of a corona polarization device, wherein a polarization medium is air, applying a voltage of 15kV, setting the distance between a polarization head and a sample to be 15mm, polarizing the temperature to be 25 ℃, and polarizing for 30min to obtain the BaTiO with the bionic electric activity₃a/P (VDF-TrFE) coated medical titanium implant material.

The composite bionic electroactive BaTiO prepared by the steps₃The main components of the coating in the medical titanium implant material of the/P (VDF-TrFE) coating are barium titanate nano particles and ferroelectric high polymer, the film thickness is 50 mu m, and the volume content of barium titanate nano particle filler in the ferroelectric high polymer matrix is 5 vol%. The electrical performance parameters of the material are as follows: the piezoelectric constant d33 was 6.58 pC/N.

(9) The obtained composite bionic electroactive BaTiO is mixed with a solvent to prepare a mixture₃The medical titanium material coated with the/P (VDF-TrFE) is implanted into the tibia of a rabbit, the PLLA coating is used as a control group, materials are respectively taken at 4 weeks and 12 weeks after operation, hard tissue section staining is carried out, the binding stability of the coating and the binding condition of new bones are intensively observed, and the binding rate of the new bones is analyzed. As shown in the drawings, the test results of this example show that, after 4 weeks of operation, the surface of the biomimetic electroactive coating material is tightly bonded to new bone, the coating material is stable and does not degrade (fig. 4B and 4D), while the surface of the PLLA coating material has poor bonding to new bone due to partial degradation of the material (fig. 4A and 4C), and the bone bonding rate of the electroactive coating is significantly higher than that of the PLLA coating (fig. 4E). After the operation of the operation for 12 weeks,the new bone maturation was increased in both groups, bone cratering was evident, the biomimetic electroactive coating remained stable (fig. 5B), while the PLLA coating further degraded and the new bone was less strongly associated than the electroactive coating group (fig. 5A).

Example 2

(1) Firstly, using SiO to make conventional medical pure titanium cylinder₂The granules were grit blasted at a pressure of 0.4MPa and then treated with 10% H₂SO₄Acid etching with 10% HCl mixed solution at 60 deg.C for 60 min;

(2) mixing nanometer strontium titanate (SrTiO)₃) Putting the particles into a dopamine aqueous solution, heating and stirring in a water bath at 60 ℃ for 12 hours, and centrifugally drying to obtain a barium titanate nanoparticle filler;

(3) dispersing a proper amount of the strontium titanate nano-particle filler prepared in the step (2) in 3ml of organic solvent (such as DMF), and stirring for 6 hours by adopting stirring and ultrasonic oscillation to obtain barium titanate particle filler dispersion liquid;

(4) dispersing 1g polymer (such as P (VDF-TrFE)) powder in 7ml organic solvent (such as DMF), stirring for 6 hr to completely dissolve to obtain polymer (such as P (VDF-TrFE)) solution;

(5) mixing the strontium titanate particle filler dispersion liquid formed in the step (3) and the polymer (such as P (VDF-TrFE)) solution formed in the step (4), and stirring for 48h to obtain particle filler (BaTiO)₃) Uniformly dispersing the mixed solution;

(6) adding a proper amount of polylactic acid and a copolymer thereof (PLLA) into 10ml of trifluoroethanol, and stirring for 48 hours to obtain a mixed solution in which polylactic acid and a copolymer filler (PLLA) thereof are uniformly dispersed;

(7) respectively uniformly coating the mixed liquid obtained in the step (5) and the step (6) on the surface of the titanium column subjected to sand blasting-acid etching treatment, and drying at the temperature of 60 ℃ for 4 hours to completely volatilize the solvent and obtain a uniform coating compounded on the surface of the titanium column;

(8) placing the titanium column with the composite uniform coating prepared in the step (7) on a sample table of a corona polarization device, wherein a polarization medium is air, applying a voltage of 15kV, setting the distance between a polarization head and a sample to be 20mm, polarizing the temperature to be 25 ℃, and polarizing for 20min to obtain SrTiO with bionic electric activity₃of/P (VDF-TrFE) coatingsMedical titanium implant materials.

The composite bionic electroactive SrTiO prepared by the steps₃The main components of the coating in the medical titanium implant material of the/P (VDF-TrFE) coating are strontium titanate nano-particles and ferroelectric high polymer, the film thickness is 30 mu m, and the volume content of the strontium titanate nano-particle filler in the ferroelectric high polymer matrix is 7 vol%. The electrical performance parameters of the material are as follows: the piezoelectric constant d33 was 6.47 pC/N.

(9) The obtained composite bionic electroactive SrTiO is₃The medical titanium material coated with the/P (VDF-TrFE) is implanted into the tibia of a rabbit, the PLLA coating is used as a control group, materials are respectively taken at 4 weeks and 12 weeks after operation, hard tissue section staining is carried out, the binding stability of the coating and the binding condition of new bones are intensively observed, and the binding rate of the new bones is analyzed.

Example 3

(1) Firstly, using SiO to make conventional medical pure titanium cylinder₂The granules were grit blasted at a pressure of 0.4MPa and then treated with 10% H₂SO₄Acid etching with 10% HCl mixed solution at 60 deg.C for 10 min;

(2) putting the nano potassium-sodium niobate (KNN) particles into dopamine aqueous solution, heating and stirring in a 60-DEG water bath for 12 hours, and centrifugally drying to obtain barium titanate nano particle filler;

(3) dispersing a proper amount of the potassium-sodium niobate nano-particle filler (KNN) prepared in the step (2) in 3ml of an organic solvent (such as DMF), and stirring for 3 hours by adopting stirring and ultrasonic oscillation to obtain barium titanate particle filler dispersion liquid;

(4) dispersing 1g polymer (such as P (VDF-TrFE)) powder in 7ml organic solvent (such as DMF), stirring for 3 hr to completely dissolve to obtain polymer (such as P (VDF-TrFE)) solution;

(5) mixing the barium titanate particle filler dispersion liquid formed in the step (3) and the polymer (such as P (VDF-TrFE)) solution formed in the step (4), and stirring for 12h to obtain particle filler (BaTiO)₃) Uniformly dispersing the mixed solution;

(6) adding a proper amount of polylactic acid and a copolymer thereof (PLLA) into 10ml of trifluoroethanol, and stirring for 12h to obtain a mixed solution in which polylactic acid and a copolymer filler (PLLA) thereof are uniformly dispersed;

(7) respectively uniformly coating the mixed liquid obtained in the step (5) and the step (6) on the surface of the titanium column subjected to sand blasting-acid etching treatment, and drying at the temperature of 100 ℃ for 1h to completely volatilize the solvent and obtain a uniform coating compounded on the surface of the titanium column;

(8) and (3) placing the titanium column with the composite uniform coating prepared in the step (7) on a sample table of a corona polarization device, applying a voltage of 10kV to the polarization medium, setting the distance between a polarization head and the sample to be 15mm, polarizing the polarization temperature to be 25 ℃, and polarizing for 40min to obtain the medical titanium implant material with the bionic electroactive KNN/P (VDF-TrFE) coating.

The main components of the coating in the medical titanium implant material of the composite bionic electroactive KNN/P (VDF-TrFE) coating obtained by the steps are potassium-sodium niobate nano-particles and ferroelectric high polymer, the film thickness is 80 mu m, and the volume content of potassium-sodium niobate nano-particle filler in a ferroelectric high polymer matrix is 10 vol%. The electrical performance parameters of the material are as follows: the piezoelectric constant d33 is 5.76 pC/N.

(9) Implanting the medical titanium material with the composite bionic electroactive KNN/P (VDF-TrFE) coating into a tibia of a rabbit, taking a PLLA coating as a control group, respectively taking materials at 4 weeks and 12 weeks after operation, staining hard tissue sections, observing the binding stability of the coating and the binding condition of new bones in a focused manner, and analyzing the binding rate of the new bones.

Example 4

(1) Firstly, using SiO to make conventional medical pure titanium cylinder₂The granules were grit blasted at a pressure of 0.4MPa and then treated with 10% H₂SO₄Acid etching with 10% HCl mixed solution at 60 deg.C for 5 min;

(2) putting the nano Lithium Niobate (LN) particles into a dopamine aqueous solution, heating and stirring in a 60-DEG water bath for 12 hours, and centrifugally drying to obtain a barium titanate nano particle filler;

(3) dispersing a proper amount of the lithium niobate nano-particle filler prepared in the step (2) in 3ml of organic solvent (such as DMF), and stirring for 6 hours by adopting stirring and ultrasonic oscillation to obtain barium titanate particle filler dispersion liquid;

(4) dispersing 1g polymer (such as P (VDF-TrFE)) powder in 7ml organic solvent (such as DMF), stirring for 6 hr to completely dissolve to obtain polymer (such as P (VDF-TrFE)) solution;

(5) mixing the lithium niobate particle filler dispersion liquid formed in the step (3) and the polymer (such as P (VDF-TrFE)) solution formed in the step (4), and stirring for 48h to obtain particle filler (BaTiO)₃) Uniformly dispersing the mixed solution;

(6) adding a proper amount of polylactic acid and a copolymer thereof (PLLA) into 10ml of trifluoroethanol, and stirring for 48 hours to obtain a mixed solution in which polylactic acid and a copolymer filler (PLLA) thereof are uniformly dispersed;

(7) respectively uniformly coating the mixed liquid obtained in the step (5) and the step (6) on the surface of the titanium column subjected to sand blasting-acid etching treatment, and drying at the temperature of 80 ℃ for 2 hours to completely volatilize the solvent and obtain a uniform coating compounded on the surface of the titanium column;

(8) and (3) placing the titanium column with the composite uniform coating prepared in the step (7) on a sample table of a corona polarization device, applying a voltage of 30kV to the polarization medium, setting the distance between a polarization head and the sample to be 20mm, polarizing the polarization temperature to be 25 ℃, and polarizing for 20min to obtain the medical titanium implant material with the bionic electroactive LN/P (VDF-TrFE) coating.

The main components of the coating in the medical titanium implant material of the composite bionic electroactive LN/P (VDF-TrFE) coating obtained by the steps are lithium niobate nano-particles and ferroelectric high polymer, the film thickness is 100 mu m, and the volume content of the lithium niobate nano-particle filler in the ferroelectric high polymer matrix is 15 vol%. The electrical performance parameters of the material are as follows: the piezoelectric constant d33 was 5.2 pC/N.

(9) Implanting the medical titanium material with the composite bionic electroactive LN/P (VDF-TrFE) coating into a tibia of a rabbit, taking a PLLA coating as a control group, respectively taking materials at 4 weeks and 12 weeks after operation, staining hard tissue sections, observing the binding stability of the coating and the binding condition of new bones in a focused manner, and analyzing the binding rate of the new bones.

Comparative example

(1) Firstly, performing sand blasting treatment on a conventional medical pure titanium cylinder by using SiO2 particles under the pressure condition of 0.4MPa, and then performing acid etching for 30min by using a mixed solution of 10% H2SO4 and 10% HCl under the constant temperature condition of 60 ℃;

(2) dispersing 1g polymer (such as P (VDF-TrFE)) powder in 10ml organic solvent (such as DMF), stirring for 3 hr to completely dissolve to obtain polymer (such as P (VDF-TrFE)) solution;

(3) uniformly coating the polymer solution obtained in the step (2) on the surface of the titanium column subjected to sand blasting-acid etching treatment, and drying at the temperature of 80 ℃ for 2h to completely volatilize the solvent and obtain a uniform coating compounded on the surface of the titanium column;

(4) and (4) placing the titanium column with the composite uniform coating prepared in the step (3) on a sample table of a corona polarization device, applying a voltage of 15kV to the titanium column with the air as a polarization medium, setting the distance between a polarization pole head and a sample to be 15mm, polarizing the titanium column at the temperature of 25 ℃, and polarizing the titanium column for 30min to obtain the medical titanium implant material with the coating.

The main component of the coating in the medical titanium implant material with the coating obtained by the steps is ferroelectric high polymer, and the thickness of the coating is 50 mu m.

The electrical performance parameters of the material are as follows: the piezoelectric constant d33 is 3.68 pC/N.

However, the above description is only exemplary of the present invention, and the scope of the present invention should not be limited thereby, and the replacement of the equivalent components or the equivalent changes and modifications made according to the protection scope of the present invention should be covered by the claims of the present invention.