Biological ceramic prepared based on flexible CF / HA wire and method

Abstract

The invention provides biological ceramic prepared based on a flexible CF / HA wire and a method, and the method comprises the following steps: uniformly dividing target carbon fibers by adopting a dichotomy method to obtain a plurality of carbon fiber bundles, and preparing target slurry; wrapping a carbon fiber bundle with the target slurry to obtain a flexible CF / HA wire; the flexible CF / HA wires are woven in a first preset mold in a parallel and / or spiral arrangement mode, the woven flexible CF / HA wires and the first preset mold are baked and dried together, and first biological ceramics are formed; a separation membrane is arranged in a second preset mold, the flexible CF / HA wires are arranged and stacked on the separation membrane in parallel, and the stacked CF / HA wires and the second preset mold are baked and dried together to prepare a second kind of biological ceramic; after the first biological ceramic and / or the second biological ceramic are / is subjected to densification sintering degreasing treatment, carbon fibers are removed, and the microtubular first biological ceramic and / or the microtubular second biological ceramic are / is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical bioceramics, and in particular to a bioceramic prepared based on flexible CF / HA wires and a method thereof. Background Art

[0002] In order to solve the defects of allogeneic or autologous transplants, such as lack of bone source, carrying pathogens and inducing immune rejection, bone tissue engineering scaffolds have been widely studied. As a platform for cell adhesion, differentiation and proliferation to achieve bone regeneration, bone tissue engineering scaffolds must have many properties, such as mechanical properties close to adjacent bones, biocompatibility and degradation ability.

[0003] Many studies have explored various biomaterials for the fabrication of bone tissue engineering scaffolds, including medical-grade metals, ceramics, polymers, and their composites. Among the different bioceramics, hydroxyapatite (HA) is the main mineral component of human bones and the skeletal system of vertebrates, and is well known for its bioactivity, biocompatibility, and osteoconductivity. After implantation into the human body, HA actively interacts with the surrounding tissues, releases ions to induce osteogenic gene expression, and promotes the growth of new bone tissue. Its reasonable price and basic properties make it a suitable material for the fabrication of bone tissue engineering scaffolds.

[0004] However, due to the inherent properties of ceramic materials, it is difficult to produce scaffolds with complex structures and controllable pore sizes using traditional processing techniques such as separation, freeze drying, solvent casting, gas foaming, and electrospinning. The rise of 3D printing technology provides a method for the rapid, precise, and personalized design and production of bone scaffolds. Belonging to the family of bone tissue engineering scaffolds, bone cage implants and bone screw implants have been used for spinal fusion, repair of long bone segment defects, first metatarsophalangeal joint fusion, primary metacarpal V-shaped repair, and reconstruction of large areas of bone loss in the midfoot. Cage and screw implants are used to stabilize and maintain the space between the two ends of the defect as new bone grows around and / or through the device, ultimately repairing severe bone defects.

[0005] However, in the existing related technologies, when 3D printing is used to manufacture HA bone cages and HA screws in bioceramics, there are technical problems such as low printing accuracy and unstable structure. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention provides a bioceramic and method prepared based on flexible CF / HA filaments, which are used to solve the technical problems of low printing accuracy and unstable structure when 3D printing bioceramics is manufactured in the prior art.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for preparing a bioceramic based on a flexible CF / HA filament comprises the following steps:

[0009] The target carbon fiber is evenly divided into a plurality of carbon fiber bundles by using a binary method, and the carbon fiber bundles are separated to obtain a preset number of carbon fiber bundles;

[0010] Prepare glycerol and ammonium polyacrylate solution, select spherical hydroxyapatite, whisker hydroxyapatite and cellulose powder in a preset ratio and mix them with the glycerol and ammonium polyacrylate solution to obtain a target slurry;

[0011] The target slurry is wrapped around the carbon fiber bundle to obtain a flexible CF / HA filament;

[0012] Weaving the flexible CF / HA filaments in a first preset mold in a parallel and / or spiral arrangement, and baking and drying the woven flexible CF / HA filaments and the first preset mold together to form a first bioceramic;

[0013] A separation membrane is arranged inside the second preset mold, and the flexible CF / HA filaments are stacked in parallel on the separation membrane, and the stacked CF / HA filaments are baked and dried together with the second preset mold to form a second bioceramic;

[0014] After the first bioceramic and / or the second bioceramic are subjected to densification, sintering and degreasing treatment, the carbon fibers are removed to obtain the microtubular first bioceramic and / or the second bioceramic.

[0015] Further, the process of preparing glycerol and ammonium polyacrylate solution is as follows:

[0016] Deionized water and glycerol are mixed in a mass ratio of 8:2 to 9:1 to prepare an initial solution;

[0017] Add ammonium polyacrylate to the initial solution, the mass of the ammonium polyacrylate being 0.9% to 1% of the mass of the initial solution, and stir evenly to obtain a glycerol and ammonium polyacrylate solution.

[0018] Furthermore, the length of the whisker hydroxyapatite ranges from 60 μm to 100 μm, and the aspect ratio is 40 to 50;

[0019] The diameter of the spherical hydroxyapatite is less than 100 nm;

[0020] The mass ratio of the spherical hydroxyapatite to the whisker hydroxyapatite is 95:5 to 99:1;

[0021] The cellulose powder accounts for 5% to 8% of the total mass of the spherical hydroxyapatite.

[0022] Furthermore, the solid-to-liquid ratio of the spherical hydroxyapatite, whisker hydroxyapatite, cellulose powder, glycerol and ammonium polyacrylate solution is 15% to 20%.

[0023] Furthermore, after the spherical hydroxyapatite, the whisker hydroxyapatite and the cellulose powder are mixed with the glycerol and the ammonium polyacrylate solution, a uniform mixed slurry is obtained by ultrasonic stirring for 3-10 minutes;

[0024] After the uniformly mixed slurry is centrifuged at a speed of 2000-3000 rpm for 5-10 minutes in a centrifuge, the uniformly mixed slurry is placed in a vacuum environment for 30-60 minutes to remove bubbles; the centrifugal treatment and vacuum degassing treatment steps are repeated at least three times.

[0025] Furthermore, the process of wrapping the target slurry with the carbon fiber bundle to obtain the flexible CF / HA filament is as follows:

[0026] The carbon fiber bundle is drawn from the inlet through a fine needle and then enters the nozzle;

[0027] Use an air pump or a syringe pump to push the barrel so that the target slurry enters the nozzle;

[0028] The target slurry and the carbon fiber bundle are fully infiltrated in the nozzle, and the target slurry covers the carbon fiber bundle and is printed out from the nozzle to form a flexible CF / HA filament.

[0029] Furthermore, the first preset mold is a cylindrical graphite structure with an inner diameter of 10 to 30 mm;

[0030] The braided flexible CF / HA filaments and the first preset mold are baked and dried together, wherein the baking and drying is carried out in a drying oven, the temperature of the drying oven is 60 to 80° C., and the drying time is 10 to 30 minutes;

[0031] The first bioceramic is a green body of a HA ceramic cage.

[0032] Furthermore, the second preset mold includes an upper mold and a lower mold, and the second bioceramic is a HA bone screw;

[0033] Based on the size of the HA bone screw and the shrinkage rate during drying, degreasing and sintering, the size of the flexible CF / HA wire is cut;

[0034] A separation membrane is coated in the lower mold, the sheared flexible CF / HA filaments are arranged in parallel and stacked in the lower mold coated with the separation membrane, and the lower mold and the upper mold are molded together;

[0035] The mold is placed in a drying oven and dried at 60-80° C. for 10-30 minutes, the HA ceramic bone nail is taken out, and the separation membrane is removed to obtain a green body of the HA ceramic bone nail.

[0036] Furthermore, the process of the densification sintering and degreasing treatment is as follows:

[0037] The first bioceramic and / or the second bioceramic are placed in a muffle furnace, heated to 300-400° C. at 1° C. / min and kept at this temperature for 2-3 hours to perform degreasing to remove glycerol, cellulose and ammonium polyacrylate in the slurry;

[0038] The first bioceramic and / or the second bioceramic after degreasing are placed in a vacuum environment for sintering at a sintering temperature of 1200 to 1400° C., a sintering time of 0.5 to 1 h, and a heating rate of 10° C. / min;

[0039] The process of removing carbon fiber is as follows:

[0040] The densified and sintered first bioceramic and / or second bioceramic are placed in a muffle furnace, heated to 500-700° C. at 1° C. / min and kept warm for 2-4 hours to obtain microtubular first bioceramic and / or second bioceramic.

[0041] A bioceramic prepared based on flexible CF / HA filaments is prepared based on the method for preparing a bioceramic based on flexible CF / HA filaments, and the bioceramic includes a microtubular first bioceramic and / or a second bioceramic.

[0042] Compared with the prior art, the present invention has the following beneficial technical effects:

[0043] The present invention provides a method for preparing a bioceramic based on a flexible CF / HA filament, comprising the following steps: using a dichotomy method to equally divide a target carbon fiber to obtain a plurality of carbon fiber bundles, separating the carbon fiber bundles to obtain a preset number of carbon fiber bundles; preparing a glycerol and ammonium polyacrylate solution, selecting a preset ratio of spherical hydroxyapatite, whisker hydroxyapatite and cellulose powder to mix with the glycerol and ammonium polyacrylate solution to obtain a target slurry; wrapping the carbon fiber bundle with the target slurry to obtain a flexible CF / HA filament; weaving the flexible CF / HA filament in a first preset mold in a parallel and / or spiral arrangement, baking and drying the woven flexible CF / HA filament and the first preset mold together to form a first bioceramic; setting a second preset mold inside the second preset mold. A separation membrane is provided, and the flexible CF / HA filaments are stacked in parallel on the separation membrane, and the stacked CF / HA filaments are baked and dried together with a second preset mold to form a second bioceramic; after the first bioceramic and / or the second bioceramic are subjected to densification, sintering and degreasing treatment, the carbon fiber is removed to obtain the microtubular first bioceramic and / or the second bioceramic; the present application can improve the braiding and deformation ability of the flexible CF / HA filaments through the carbon fiber bundle, and improve the structural accuracy of the bioceramic. At the same time, the carbon fiber bundle can be used for adjusting the pore size of the bioceramic, so as to obtain the bioceramic with the required mechanical properties and porosity, which solves the technical problems of low printing accuracy and unstable structure in the existing related technology when 3D printing is used to manufacture bioceramics.

[0044] The present invention provides a bioceramic prepared based on flexible CF / HA filaments, which is prepared by the method for preparing bioceramics based on flexible CF / HA filaments. The bioceramic includes a microtubular first bioceramic and / or a second bioceramic. The microtubular first bioceramic and / or the second bioceramic described in the present application have higher structural accuracy, better mechanical properties and controllable porosity. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is the XRD pattern of HA microtubes of the embodiment of the present disclosure;

[0046] FIG2 is a SEM image of the microstructure of HA microtubes formed after heat treatment of 30 CF flexible CF / HA blanks according to an embodiment of the present disclosure;

[0047] Figure 3 Appearance diagram of HA ceramic bone cages with two different structures prepared in Example 1 and Example 2 of the embodiments of the present disclosure;

[0048] FIG4 is a surface micrograph of HA ceramic cages with two different structures prepared in Example 1 and Example 2 of the present disclosure;

[0049] Figure 5 A microscopic image of a cross section of a HA ceramic bone cage having a parallel structure prepared in Example 1 of the disclosed embodiment;

[0050] Figure 6 This is an appearance diagram of the HA ceramic bone screw prepared in Example 3 of the disclosed embodiment;

[0051] Figure 7 The compressive stress-strain curve of the HA ceramic bone nail prepared in Example 3 of the embodiment of the present disclosure;

[0052] Figure 8 This is the pull-out force-displacement curve of the HA ceramic bone screw prepared in Example 3 of the embodiments of the present disclosure. DETAILED DESCRIPTION

[0053] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0054] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0055] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0056] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0057] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0058] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0059] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0060] The present disclosure provides a method for preparing a bioceramic based on a flexible CF / HA filament, comprising the following steps:

[0061] Step S1: using a binary method to equally divide the target carbon fiber into multiple carbon fiber bundles, and separating the carbon fiber bundles to obtain a preset number of carbon fiber bundles;

[0062] Specifically, before the target carbon fiber is divided into multiple carbon fiber bundles by the dichotomy method, the carbon fiber bundle needs to be cleaned to remove the sizing agent on the surface, and the 1K cleaned carbon fiber bundle (CF) is divided into 10 parts by the dichotomy method, and then one end of the divided CF bundle is soaked in an acetone solution to separate and take out the CF bundle with the required number of carbon fiber roots.

[0063] Step S2: preparing a glycerol and ammonium polyacrylate solution, selecting a preset ratio of spherical hydroxyapatite, whisker hydroxyapatite and cellulose powder, and mixing them with the glycerol and ammonium polyacrylate solution to obtain a target slurry;

[0064] Preferably, in the embodiment of the present disclosure, the process of preparing the glycerol and ammonium polyacrylate solution is:

[0065] Deionized water and glycerol are mixed in a mass ratio of 8:2 to 9:1 to prepare an initial solution;

[0066] Add ammonium polyacrylate to the initial solution, the mass of the ammonium polyacrylate being 0.9% to 1% of the mass of the initial solution, and stir evenly to obtain a glycerol and ammonium polyacrylate solution.

[0067] Furthermore, a hydrothermal method is used to prepare whisker hydroxyapatite, wherein the whisker hydroxyapatite has a length ranging from 60 μm to 100 μm and an aspect ratio of 40 to 50;

[0068] The diameter of the spherical hydroxyapatite is less than 100 nm;

[0069] The mass ratio of the spherical hydroxyapatite to the whisker hydroxyapatite is 95:5 to 99:1;

[0070] The cellulose powder accounts for 5% to 8% of the total mass of the spherical hydroxyapatite.

[0071] It should be noted that the size and proportion range of the above-mentioned spherical hydroxyapatite and whisker hydroxyapatite are determined by experimental research in this application, and the addition of the whisker hydroxyapatite can improve the filament printing performance, deformation ability, and flexibility, which is more conducive to weaving bone cages and facilitating the printing of complete structure bone cages and bone screws and other bone implants.

[0072] Furthermore, the solid-to-liquid ratio of the spherical hydroxyapatite, whisker hydroxyapatite, cellulose powder, glycerol and ammonium polyacrylate solution is 15% to 20%.

[0073] In some embodiments, after the spherical hydroxyapatite, whisker hydroxyapatite and cellulose powder are mixed with glycerol and ammonium polyacrylate solution, ultrasonic stirring is performed for 3-10 minutes to obtain a uniform mixed slurry;

[0074] After the uniformly mixed slurry is centrifuged at a speed of 2000-3000 rpm for 5-10 minutes in a centrifuge, the uniformly mixed slurry is placed in a vacuum environment for 30-60 minutes to remove bubbles; the centrifugal treatment and vacuum degassing treatment steps are repeated at least three times.

[0075] Step S3: wrap the target slurry with a carbon fiber bundle to obtain a flexible CF / HA filament; it should be noted that, in some embodiments, the number of wrapped carbon fiber bundles can be selected. On the one hand, the carbon fiber bundles can improve the plasticity during printing, that is, improve the accuracy of the structural size. On the other hand, the carbon fiber bundles can be used for pore-forming agents to make holes. The process is simple, and a microtube structure with controllable porosity can be obtained by changing the number and distribution structure of the carbon fiber bundles.

[0076] Preferably, in the disclosed embodiment, the process of wrapping the target slurry with the carbon fiber bundle to obtain the flexible CF / HA filament is:

[0077] The carbon fiber bundle is drawn from the inlet through a fine needle and then enters the nozzle;

[0078] Use an air pump or a syringe pump to push the barrel so that the target slurry enters the nozzle;

[0079] The target slurry and the carbon fiber bundle are fully infiltrated in the nozzle, and the target slurry covers the carbon fiber bundle and is printed out from the nozzle to form a flexible CF / HA filament.

[0080] Specifically, in some embodiments, the driving air pressure of the air pump is 0.2-0.4 MPa, and the flow rate of the syringe pump is 0.4-0.6 ml / sec;

[0081] The formed flexible CF / HA wire has a diameter of 1000-1500 μm.

[0082] It should be noted that the carbon fiber bundle plays a skeleton role in the flexible CF / HA blank, which can improve the braidability and deformation ability of the flexible CF / HA blank so as to form bone cages, bone screws and other bone implants. In addition, by using different numbers of carbon fiber bundles to control the pore size, bone cages, bone screws and other bone implants with the required mechanical properties and porosity can be obtained.

[0083] Step S4: weaving the flexible CF / HA filaments in a first preset mold in a parallel and / or spiral arrangement, and baking and drying the woven flexible CF / HA filaments and the first preset mold together to form a first bioceramic;

[0084] Specifically, the first preset mold is a cylindrical graphite structure with an inner diameter of 10 to 30 mm;

[0085] The braided flexible CF / HA filaments and the first preset mold are baked and dried together, wherein the baking and drying is carried out in a drying oven, the temperature of the drying oven is 60 to 80° C., and the drying time is 10 to 30 minutes;

[0086] The first bioceramic is a green body of a HA ceramic cage.

[0087] It should be noted that the flexible CF / HA filaments may be multiple, for example, 1 to 10, and when the flexible CF / HA filaments are arranged in a spiral, the spiral pitch is 4 to 12 mm.

[0088] Step S5: a separation membrane is arranged inside the second preset mold, the flexible CF / HA filaments are stacked in parallel on the separation membrane, and the stacked CF / HA filaments are baked and dried together with the second preset mold to form a second bioceramic;

[0089] Specifically, the second preset mold includes an upper mold and a lower mold, and the second bioceramic is a HA bone nail;

[0090] Based on the size of the HA bone screw and the shrinkage rate during drying, degreasing and sintering, the size of the flexible CF / HA wire is cut;

[0091] A separation membrane is coated in the lower mold, the sheared flexible CF / HA filaments are arranged in parallel and stacked in the lower mold coated with the separation membrane, and the lower mold and the upper mold are molded together;

[0092] The mold is placed in a drying oven and dried at 60-80° C. for 10-30 minutes, the HA ceramic bone nail is taken out, and the separation membrane is removed to obtain a green body of the HA ceramic bone nail.

[0093] Step S6: After densification, sintering and degreasing treatment of the first bioceramic and / or the second bioceramic, the carbon fibers are removed to obtain the micro-tubular first bioceramic and / or the second bioceramic.

[0094] In some embodiments, the densification sintering and debinding process is as follows:

[0095] The first bioceramic and / or the second bioceramic are placed in a muffle furnace, heated to 300-400° C. at 1° C. / min and kept at this temperature for 2-3 hours to perform degreasing to remove glycerol, cellulose and ammonium polyacrylate in the slurry;

[0096] The first bioceramic and / or the second bioceramic after degreasing are placed in a vacuum environment for sintering at a sintering temperature of 1200 to 1400° C., a sintering time of 0.5 to 1 h, and a heating rate of 10° C. / min;

[0097] The process of removing carbon fiber is as follows:

[0098] The densified and sintered first bioceramic and / or second bioceramic are placed in a muffle furnace, heated to 500-700° C. at 1° C. / min and kept warm for 2-4 hours to obtain microtubular first bioceramic and / or second bioceramic.

[0099] The disclosed embodiments also provide a bioceramic prepared based on flexible CF / HA filaments, which is prepared based on the method for preparing bioceramics based on flexible CF / HA filaments, and the bioceramic includes a first microtubular bioceramic and / or a second bioceramic; it should be noted that the microtubular shape has a connected microtubular structure, which helps to effectively provide nutrients to promote cell response.

[0100] Specifically, those skilled in the art can customize the shape of the HA ceramic bone cage and the thread parameters of the HA ceramic bone screw according to actual needs to meet the needs of different medical occasions such as spinal fusion and repair of long bone segment defects.

[0101] It should be noted that the compression strength and pull-out force of the HA ceramic bone screw disclosed in this embodiment can meet the requirements of cancellous bone implants, providing a new choice in the field of biomedical materials for bone defect repair; at the same time, the HA ceramic bone cage and HA ceramic bone screw have good degradation properties, which can avoid the trauma caused by secondary surgery.

[0102] The present application discloses the following embodiments. It should be noted that, in the following embodiments, the carbon fiber is CF, the hydroxyapatite is HA, and the ammonium polyacrylate is PAA.

[0103] Embodiment 1:

[0104] Step 1, the carbon fiber (CF) is cleaned in an ultrasonic cleaner with pure water, anhydrous ethanol, acetone and distilled water to remove the sizing agent, and the cleaning setting parameters of the ultrasonic cleaner are: frequency (60.0KHz), power (100.0W), cleaning time (30.0min); 1K carbon fiber is divided into 10 parts by dichotomy, and then one end of the divided carbon fiber (CF) bundle is soaked in acetone, and 30 carbon fiber (CF) bundles are separated and taken out;

[0105] Step 2: Measure 5.10 g of glycerol (C3H8O3) and 45.95 ml of water, mix and stir for 3 minutes to make them evenly mixed to prepare solution A.

[0106] Step 3: Add ammonium polyacrylate to solution A, the mass of ammonium polyacrylate is 0.48 g, and stir evenly to obtain solution B.

[0107] Step 4: Weigh 5.87 g of spherical HA, 0.442 g of whisker-shaped HA and 0.378 g of cellulose powder. Figure 1 As shown, XRD test shows that the main component of microtubules is HA, and there is a trace amount of β-TCP produced by high-temperature decomposition of HA.

[0108] Step 5: Mix the powder weighed in step 4 with 9.76 ml of solution B, and stir ultrasonically for 10 minutes to mix them evenly to form the target slurry. Centrifuge the slurry at 2300 rpm for 5 minutes in a centrifuge, then place the slurry in a vacuum environment for 30 minutes to remove bubbles. Repeat the centrifugation and vacuum degassing steps three times until most of the bubbles are removed.

[0109] Step 6: Feed the continuous CF bundle into the fiber tube of the nozzle, and then feed the prepared HA slurry into the barrel, and use an air pump to feed the slurry from the barrel into the nozzle and extrude it at a pressure of 0.3 MPa. Wrap the fiber bundle in the HA slurry and deposit it on a Teflon plate to obtain a flexible CF / HA blank. As shown in Figure 2, Figure 2 (a) is a cross-sectional SEM image of the HA microtube obtained after heat treatment of the flexible CF / HA blank, and Figure 2 (b) is an enlarged SEM image of the hole part in Figure 2 (a).

[0110] Step 7. Arrange the two printed flexible CF / HA blanks in parallel and then tightly wrap and weave them on a cylindrical graphite mold with an inner diameter of 12 mm. Place the ceramic cage and the cylindrical graphite mold in a drying oven and slowly dry them at 60°C for 10 minutes. Then take the HA ceramic cage out of the mold to obtain the HA ceramic cage blank.

[0111] Step 8. Place the HA ceramic cage body in a muffle furnace, heat it to 400°C at 1°C / min and keep it warm for 180 minutes, cool it with the furnace, and degrease to remove glycerol, cellulose and PAA in the slurry. Sinter the degreased body directly in a vacuum environment at a sintering temperature of 1350°C. Keep it warm for 30 minutes when the temperature reaches the highest. Both the heating and cooling rates are set to 10°C / min. Finally, perform low-temperature pore making. Place the densified sintered body in a muffle furnace, heat it to 600°C at 10°C / min and keep it warm for 180 minutes, cool it with the furnace, and obtain the finished HA ceramic cage. Figure 3 and Figure 4(a) show the macroscopic image and surface micromorphology of the HA ceramic cage, respectively. Figure 5 This is a cross-sectional ultra-depth image of the HA ceramic cage, which proves that the ceramic cage is composed of microtubes.

[0112] Embodiment 2:

[0113] Step 1. Clean the CF in an ultrasonic cleaner with pure water, anhydrous ethanol, acetone and distilled water in turn to remove the sizing agent. The cleaning setting parameters of the ultrasonic cleaner are: frequency (60.0KHz), power (100.0W), and cleaning time (30.0min); use the binary method to divide 1K carbon fiber into 10 parts, and then soak one end of the divided CF bundle in acetone, separate and take out the CF bundle with 30 carbon fibers.

[0114] Step 2: Measure 5.10 g of glycerol (C3H8O3) and 45.95 ml of water, mix and stir for 3 minutes to make them evenly mixed to prepare solution A.

[0115] Step 3: Add ammonium polyacrylate to solution A, the mass of ammonium polyacrylate is 0.48 g, and stir evenly to obtain solution B.

[0116] Step 4: Weigh 5.87 g of spherical HA, 0.442 g of whisker-like HA and 0.378 g of cellulose powder.

[0117] Step 5: Mix the powder weighed in step 4 with 9.76 ml of solution B, and stir ultrasonically for 10 minutes to mix them evenly to form a slurry. Centrifuge the slurry at 2300 rpm for 5 minutes in a centrifuge, then place the slurry in a vacuum environment for 30 minutes to remove bubbles. Repeat the centrifugation and vacuum degassing steps three times until most of the bubbles are removed.

[0118] Step 6: Feed the continuous CF bundle into the fiber tube of the nozzle. Then feed the prepared HA slurry into the barrel, and use an air pump to feed the slurry from the barrel into the nozzle and extrude it at a pressure of 0.3 MPa. Wrap the fiber bundle in the HA slurry and deposit it on the Teflon plate. Get a flexible CF / HA blank.

[0119] Step 8. Fix one end of the two printed flexible CF / HA blanks and twist the other end to obtain a spiral structure blank with a pitch of 6 mm. Then tightly wind and weave the flexible CF / HA blank with a spiral structure on a cylindrical graphite mold with an inner diameter of 12 mm. Place the ceramic cage and the cylindrical graphite mold in a drying oven and slowly dry them at 60°C for 10 minutes. Then take the HA ceramic cage out of the mold to obtain a blank with a spiral structure HA ceramic cage.

[0120] Step 9. Place the HA ceramic cage body with a spiral structure in a muffle furnace, heat it to 400°C at 1°C / min and keep it warm for 180 minutes, cool it with the furnace, and degrease to remove glycerol, cellulose and PAA in the slurry. The degreased body is directly sintered in a vacuum environment at a sintering temperature of 1350°C. When the temperature reaches the highest, keep it warm for 30 minutes. The heating and cooling rates are both set to 10°C / min. Finally, low-temperature pore making is performed. The densified sintered body is placed in a muffle furnace, heated to 600°C at 10°C / min and kept warm for 180 minutes. Cool it with the furnace to obtain a HA ceramic cage with a spiral structure. Figure 3 and Figure 4(b), respectively, are the macroscopic image of the HA ceramic cage with a helical structure and its surface micromorphology.

[0121] Embodiment 3:

[0122] Step 1. Clean the CF in an ultrasonic cleaner with pure water, anhydrous ethanol, acetone and distilled water in turn to remove the sizing agent. The cleaning setting parameters of the ultrasonic cleaner are: frequency (60.0KHz), power (100.0W), and cleaning time (30.0min); use the binary method to divide 1K carbon fiber into 10 parts, and then soak one end of the divided CF bundle in acetone, separate and take out the CF bundle with 30 carbon fibers.

[0123] Step 2: Measure 5.10 g of glycerol (C3H8O3) and 45.95 ml of water, mix and stir for 3 minutes to make them evenly mixed to prepare solution A.

[0124] Step 3: Add ammonium polyacrylate to solution A, the mass of ammonium polyacrylate is 0.48 g, and stir evenly to obtain solution B.

[0125] Step 4: Weigh 5.87 g of spherical HA, 0.442 g of whisker-like HA and 0.378 g of cellulose powder.

[0126] Step 5: Mix the powder weighed in step 4 with 9.76 ml of solution B, and stir ultrasonically for 10 minutes to mix them evenly to form a slurry. Centrifuge the slurry at 2300 rpm for 5 minutes in a centrifuge, then place the slurry in a vacuum environment for 30 minutes to remove bubbles. Repeat the centrifugation and vacuum degassing steps three times until most of the bubbles are removed.

[0127] Step 6: Feed the continuous CF bundle into the fiber tube of the nozzle. Then feed the prepared HA slurry into the barrel, and use an air pump to feed the slurry from the barrel into the nozzle and extrude it at a pressure of 0.3 MPa. Wrap the fiber bundle in the HA slurry and deposit it on the Teflon plate. Get a flexible CF / HA blank.

[0128] Step 7: Draw a 3D model of the thread die with specific dimensions and thread parameters, and divide it into an upper die and a lower die. Import the 3D model data into a 3D printer to print out the upper and lower dies with the highest precision.

[0129] Step 8: Cut the prepared flexible CF / HA blank into 3 cm pieces for later use, then arrange 70 3 cm filaments in parallel and stack them together tightly, and completely wrap the arranged flexible CF / HA blank with a layer of separation film to avoid damaging the surface threads of the HA bone screw during demoulding.

[0130] Step 9: Place the flexible CF / HA blank wrapped with the separation membrane in the lower concave mold, and then close the upper and lower molds. Place it in a drying oven and slowly dry it at 60°C for 10 minutes. Then take the HA ceramic bone nail out of the mold and remove the separation membrane to obtain the HA ceramic bone nail blank.

[0131] Step 10. Place the HA ceramic bone nail blank in a muffle furnace, heat it to 400°C at 1°C / min and keep it warm for 180 minutes, and perform degreasing to remove glycerol, cellulose and PAA in the slurry. Sinter the degreased blank directly in a vacuum environment at a sintering temperature of 1350°C. Keep it warm for 30 minutes when the temperature reaches the highest point. Both the heating and cooling rates are set to 10°C / min. Finally, perform low-temperature pore making. Place the densified sintered blank in a muffle furnace, heat it to 600°C at 1°C / min and keep it warm for 180 minutes to obtain a finished HA ceramic bone nail. Figure 6 The figure shows the macroscopic image of the HA bone screw and the mechanical properties of the bone screw were tested. The compressive stress-strain and pull-out force-displacement curves are shown in Figure 7 and Figure 8 shown.

[0132] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0133] In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution according to the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing bioceramics based on flexible CF / HA filaments, characterized in that: The following steps are involved: The target carbon fiber is evenly divided into a plurality of carbon fiber bundles by using a binary method, and the carbon fiber bundles are separated to obtain a preset number of carbon fiber bundles; Prepare glycerol and ammonium polyacrylate solution, select spherical hydroxyapatite, whisker hydroxyapatite and cellulose powder in a preset ratio and mix them with the glycerol and ammonium polyacrylate solution to obtain a target slurry; The target slurry is wrapped around the carbon fiber bundle to obtain a flexible CF / HA filament; Weaving the flexible CF / HA filaments in a first preset mold in a parallel and / or spiral arrangement, and baking and drying the woven flexible CF / HA filaments and the first preset mold together to form a first bioceramic; A separation membrane is arranged inside the second preset mold, and the flexible CF / HA filaments are stacked in parallel on the separation membrane, and the stacked CF / HA filaments are baked and dried together with the second preset mold to form a second bioceramic; After the first bioceramic and / or the second bioceramic are subjected to densification, sintering and degreasing treatment, the carbon fibers are removed to obtain the microtubular first bioceramic and / or the second bioceramic.

2. The method for preparing bioceramics based on flexible CF / HA filaments according to claim 1, characterized in that: The process of preparing glycerol and ammonium polyacrylate solution is as follows: Deionized water and glycerol are mixed in a mass ratio of 8:2 to 9:1 to prepare an initial solution; Add ammonium polyacrylate to the initial solution, the mass of the ammonium polyacrylate being 0.9% to 1% of the mass of the initial solution, and stir evenly to obtain a glycerol and ammonium polyacrylate solution.

3. The method for preparing bioceramics based on flexible CF / HA filaments according to claim 1, characterized in that: The length of the whisker hydroxyapatite is in the range of 60 μm to 100 μm, and the aspect ratio is 40 to 50; The diameter of the spherical hydroxyapatite is less than 100 nm; The mass ratio of the spherical hydroxyapatite to the whisker hydroxyapatite is 95:5 to 99:1; The cellulose powder accounts for 5% to 8% of the total mass of the spherical hydroxyapatite.

4. The method for preparing bioceramics based on flexible CF / HA filaments according to claim 1, characterized in that: The solid-to-liquid ratio of the spherical hydroxyapatite, the whisker hydroxyapatite, the cellulose powder, the glycerol and the ammonium polyacrylate solution is 15% to 20%.

5. The method for preparing bioceramics based on flexible CF / HA filaments according to claim 1, characterized in that: After the spherical hydroxyapatite, whisker hydroxyapatite and cellulose powder are mixed with glycerol and ammonium polyacrylate solution, a uniform mixed slurry is obtained by ultrasonic stirring for 3-10 minutes; After the uniformly mixed slurry is centrifuged at a speed of 2000-3000 rpm for 5-10 minutes in a centrifuge, the uniformly mixed slurry is placed in a vacuum environment for 30-60 minutes to remove bubbles; the centrifugal treatment and vacuum degassing treatment steps are repeated at least three times.

6. The method for preparing bioceramics based on flexible CF / HA silk according to claim 1, characterized in that: The process of wrapping the target slurry with the carbon fiber bundle to obtain the flexible CF / HA filament is as follows: The carbon fiber bundle is drawn from the inlet through a fine needle and then enters the nozzle; Use an air pump or a syringe pump to push the barrel so that the target slurry enters the nozzle; The target slurry and the carbon fiber bundle are fully infiltrated in the nozzle, and the target slurry covers the carbon fiber bundle and is printed out from the nozzle to form a flexible CF / HA filament.

7. The method for preparing bioceramics based on flexible CF / HA silk according to claim 1, characterized in that: The first preset mold is a cylindrical graphite structure with an inner diameter of 10 to 30 mm; The braided flexible CF / HA filaments and the first preset mold are baked and dried together, wherein the baking and drying is carried out in a drying oven, the temperature of the drying oven is 60 to 80° C., and the drying time is 10 to 30 minutes; The first bioceramic is a green body of a HA ceramic cage.

8. The method for preparing bioceramics based on flexible CF / HA filaments according to claim 1, characterized in that: The second preset mold includes an upper mold and a lower mold, and the second bioceramic is an HA bone screw; Based on the size of the HA bone screw and the shrinkage rate during drying, degreasing and sintering, the size of the flexible CF / HA wire is cut; A separation membrane is coated in the lower mold, the sheared flexible CF / HA filaments are arranged in parallel and stacked in the lower mold coated with the separation membrane, and the lower mold and the upper mold are molded together; The mold is placed in a drying oven and dried at 60-80° C. for 10-30 minutes, the HA ceramic bone screw is taken out, and the separation membrane is removed to obtain a green body of the HA ceramic bone screw.

9. The method for preparing bioceramics based on flexible CF / HA silk according to claim 1, characterized in that: The process of densification sintering and degreasing treatment is as follows: The first bioceramic and / or the second bioceramic are placed in a muffle furnace, heated to 300-400° C. at 1° C. / min and kept at that temperature for 2-3 hours to perform degreasing to remove glycerol, cellulose and ammonium polyacrylate in the slurry; The first bioceramic and / or the second bioceramic after degreasing are placed in a vacuum environment for sintering at a sintering temperature of 1200 to 1400° C., a sintering time of 0.5 to 1 h, and a heating rate of 10° C. / min; The process of removing carbon fiber is as follows: The densified and sintered first bioceramic and / or second bioceramic are placed in a muffle furnace, heated to 500-700° C. at 1° C. / min and kept warm for 2-4 hours to obtain microtubular first bioceramic and / or second bioceramic.

10. A bioceramic prepared based on flexible CF / HA silk, characterized in that: The bioceramic is prepared by the method for preparing a bioceramic based on flexible CF / HA filaments according to any one of claims 1 to 9, wherein the bioceramic includes a first microtubular bioceramic and / or a second bioceramic.

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