AU2020103353A4

AU2020103353A4 - Composite Material, Raw Material Composition, Bone Prosthesis, Preparation Method, and Use thereof

Info

Publication number: AU2020103353A4
Application number: AU2020103353A
Authority: AU
Inventors: Yongkang Pan; Jun Qian; Xuening Shen; Songchao TANG; Jie Wei; Lili Yang; Zhao YUAN; Jun Zhao
Original assignee: East China University of Science and Technology
Current assignee: East China University of Science and Technology
Priority date: 2020-11-10
Filing date: 2020-11-10
Publication date: 2021-01-21
Anticipated expiration: 2028-11-10

Abstract

Our Ref.: P20455525AU Abstract Disclosed are a composite material, a raw material composition, a bone prosthesis, a preparation method and use thereof. The composition comprises the following components: an LAP powder and a PI powder in a mass ratio of (1 to 2):(3 to 4), with the LAP powder having a particle size of 1to 10 pm. The composite material prepared from this composition has good bioactivity and biocompatibility, has a relatively high mechanical compatibility matching the bone tissue, and can stimulate bone growth, accelerate bone healing, and reduce healing time; the process is simple, and can prepare bone prostheses with different shapes, specifications and mechanical properties as required; the prepared bone prosthesis has good biocompatibility, bioactivity, and mechanical compatibility with bone, can reduce the bone healing time, and has high strength, good fatigue resistance and corrosion resistance, as well as a long service life; the bone prosthesis will not cause inflammation after being implanted, and has the modulus of elasticity, the toughness and the breaking strength matching human bone, which will not cause loosening of the material due to stress shielding and the negative effect of bone resorption, and can meet the clinical needs for bone repair. 1/5 Drawings Fig.1I Fig. 2 [ab Fig. 3

Description

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Drawings

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Our Ref.: P20455525AU

Composite Material, Raw Material Composition, Bone Prosthesis, Preparation Method, and Use thereof

Technical Field

[0001] The present disclosure relates to the field of biomedical materials, in particular to a composite material, a raw material composition, a bone prosthesis, a preparation method, and use thereof.

Background

[0002] With the increasing population of aging in China, the incidence of diseases such as severe bone trauma and bone degeneration has gradually increased, and new requirements have been put forward for the development of orthopedic medical devices, that is, they need to have good bioactivity and form osseointegration after being implanted in the body. However, the orthopedic fixation materials and bone defect repair materials which are widely used in clinical practice at present all have the problem of poor bioactivity.

[0003] Moreover, the titanium-based and ceramic-based bone implant materials which are widely used in clinical practice at present all have some disadvantages that are difficult to overcome by themselves; for example, metal materials have structural properties greatly different from those of bone, and thus lack bioactivity, are difficult to form osseointegration with autologous bone, and are likely to cause bone resorption. Furthermore, the dissolution of metal ions is likely to cause effusion, inflammation, necrosis, etc., and ceramic bone implant materials have disadvantages such as difficult molding and poor toughness. In addition, the mechanical strength of the metal and ceramic bone implant materials is much higher than that of bone tissue, and implanting them into the body is prone to stress shielding, which will cause bone resorption and bone atrophy, and further cause a series of complications due to loosening of the implant.

[0004] Polyimide (PI) not only has excellent biocompatibility and biostability, but also has good fatigue resistance and strong corrosion resistance. The artificial bone made of PI has a modulus of elasticity matching the bone tissue, has high strength, is hard and wear-resistant, and has a mechanical strength that is not degraded after repeated sterilization. Therefore, PI materials have more obvious advantages than metals and ceramics, and are suitable for long-term bone implantation in the body. However, PI lacks bioactivity, and cannot form a firm bond-binding with human bone.

[0005] Laponite (LAP) is an inorganic material. A large number of biocompatibility experiments have proved that the laponite is non-toxic, non-irritating, non-allergenic and non-mutagenic and will not damage biological tissues, so the laponite has good biocompatibility. However, it has certain brittleness and low strength, which limits its mechanical properties.

Our Ref.: P20455525AU

Content of the present invention

[0006] The technical problem to be solved in the present disclosure is for overcoming the defect that the existing bone repair materials have poor mechanical compatibility with bone tissues, which likely results in loosening of the bone repair materials and bone resorption due to stress shielding such that the speed of bone healing is too slow, and lack bioactivity, and are unable to form a firm bond with bone, and for providing a composite material, a raw material composition, a bone prosthesis, a preparation method and use thereof. The LAP/PI composite material has good bioactivity and biocompatibility, has a relatively high mechanical compatibility matching the bone tissue, and can stimulate the bone growth, accelerate the bone healing, and reduce the healing time after bone implantation. The process of the LAP/PI composite material is simple and feasible, and the process for preparing the LAP/PI composite material can be adjusted according to clinical needs to prepare bone prosthesis of different shapes, specifications and mechanical properties. The bone prosthesis has good biocompatibility, bioactivity, and mechanical compatibility with bone, can reduce the bone healing time, and has high strength, good fatigue resistance and corrosion resistance, and a long service life. The bone prosthesis will not cause inflammation after being implanted, and has the modulus of elasticity, the toughness, the breaking strength and other mechanical properties matching human bone, which will not cause loosening of the bone repair material due to stress shielding and the negative effect such as bone resorption, and can meet the clinical needs for bone repair.

[0007] The present disclosure achieves the above technical effects through the following technical solution.

[0008] The present disclosure provides a raw material composition of a composite material, the raw material composition comprising the following components: a laponite powder and a polyimide powder, wherein the laponite powder and the polyimide powder are in a mass ratio of (1 to 2):(3 to 4), and the laponite powder has a particle size of 1 m to 10 im.

[0009] In the present disclosure, preferably, the laponite powder has a mass fraction of 15% to 40%, the polyimide powder has a mass fraction of 60% to 85%, and more preferably, the laponite powder has a mass fraction of 20% to 30%, and the polyimide powder has a mass fraction of 70% to 80%, the above percentages being mass percentages of the components relative to the raw material composition of the composite material.

[0010] In the present disclosure, the laponite powder can be prepared and obtained by a conventional method in the art, preferably prepared by sintering and then ball-milling the raw material laponite. The raw material laponite may be a conventional laponite in the art, preferably Model LAPONITE-RDS purchased from Altana AG in Germany.

[0011] In such a case, the operation and conditions of the sintering may be conventional operation and conditions in the art, and the sintering is generally performed in a muffle furnace. The temperature of the sintering is preferably 900 °C

Our Ref.: P20455525AU

to 1100 °C, more preferably 1000 °C. The time of the sintering is preferably 3 to 4 hours. In order to reach the temperature of the sintering, the heating rate may be conventional in the art, and is preferably 2 °C/min to 5 °C/min, for example, 3.5 °C/min.

[0012] In such a case, the operation and conditions of the ball-milling may be conventional operation and conditions in the art, and the ball-milling is generally performed by means of a ball mill. The rotation speed of the ball mill may be a conventional rotation speed in the art, is preferably 450 to 550 r/min, and is more preferably 500 r/min. In such a case, the time of the ball-milling is preferably 20 to hours, more preferably 24 hours.

[0013] In the present disclosure, the laponite powder has a particle size of preferably 2 pm to 5 im, for example, 2 to 3 m.

[0014] In the present disclosure, the polyimide may be conventional thermoplastic aromatic polyimide in the art, preferably one or more of pyromellitic dianhydride type polyimide, ether-anhydride type polyimide and ketone-anhydride type polyimide, more preferably Model M1 purchased from Changzhou Junhua Special Engineering Plastic Products Co., Ltd.

[0015] In the present disclosure, the particle size of the polyimide powder may be a conventional particle size in the art, preferably 10 pm to 20 im, more preferably 12 pm to 18 im, and most preferably 15 m.

[0016] In the present disclosure, for the preparation method for the raw material composition of the composite material, the raw material composition may be prepared and obtained by a conventional method in the art, and is generally prepared by uniformly mixing the components. The mixing operation is generally performed in a mixer.

[0017] In such a case, the mixer maybe a conventional mixer in the art, and a mixer of Model SYH-2 of Changzhou Saiwei Machinery Manufacturing Co., Ltd. is used in the present disclosure. The rotation speed of the mixer may be a conventional rotation speed in the art, is preferably 500 to 700 r/min, and is more preferably 600 r/min. The mixing time may be a conventional mixing time in the art, preferably 10 to 14 hours, and more preferably 12 hours.

[0018] The present disclosure further provides a preparation method for a laponite/polyimide (LAP/PI) composite material, the method comprising the following step: molding the above raw material composition.

[0019] In the present disclosure, the method and conditions of the molding are conventional method and conditions in the art. The molding is preferably injection molding, high-temperature melt-blending molding or compression-sintering molding.

[0020] In such a case, the method and conditions of the injection molding may be conventional method and conditions in the art. The injection molding is preferably performed in an injection-molding machine. The temperature of the injection molding our Ref.: P20455525AU is preferably 260°C to 280°C. The pressure of the injection molding is preferably 100 MPa to 120 MPa.

[0021] In such a case, the method and conditions of the high-temperature melt blending molding may be conventional method and conditions in the art. The high temperature melt-blending molding is preferably performed in a twin-screw extruder. The temperature of the high-temperature melt-blending molding is preferably 260 °C to 280°C. The pressure of the high-temperature melt-blending molding is preferably 80 MPa to 100 MPa.

[0022] In such a case, the method and conditions of the compression-sintering molding may be conventional method and conditions in the art. The compression sintering molding is preferably performed as the following operation method: subjecting the mixed powder to compression molding, then heating, and sintering molding. the heating rate is preferably 1 C/min to 2°C/min. the temperature of the sintering is preferably 260°C to 280°C. the temperature-holding time of the sintering is preferably 3 h to 4 h, more preferably 3 h.

[0023] In the present disclosure, the shape of the LAP/PI composite material obtained by the molding is not limited. If the mold used in the molding is a bone prosthesis product mold, the LAP/PI composite material can be directly used as a bone prosthesis. If the mold used in the molding is not a bone prosthesis product mold, a bone prosthesis of a desired shape can be prepared by subsequent treatment operations, for example, grinding, machining, and other procedures.

[0024] The present disclosure further provides a laponite/polyimide composite material prepared and obtained by the above preparation method.

[0025] In the present disclosure, the laponite/polyimide composite material is a laponite-reinforced polyimide composite material.

[0026] The present disclosure further provides use of the laponite/polyimide composite material in a bone prosthesis.

[0027] In such a case, the bone prosthesis is a spinal bone prosthesis or a dental implant. The spinal bone prosthesis is also referred to as an intervertebral fusion cage, including a cervical intervertebral fusion cage and a thoracic/lumbar intervertebral fusion cage.

[0028] The present disclosure further provides a preparation method for a bone prosthesis, the method comprising the following step: molding the above raw material composition in a bone prosthesis product mold.

[0029] In the present disclosure, the mold for the bone prosthesis product is a conventional mold used in the preparation of a bone prosthesis product, preferably a spinal bone prosthesis mold or a dental implant mold. The spinal bone prosthesis is also referred to as an intervertebral fusion cage, including a cervical intervertebral fusion cage and a thoracic/lumbar intervertebral fusion cage.

Our Ref.: P20455525AU

[0030] In the present disclosure, the method and conditions of the molding are conventional method and conditions in the art. The molding is preferably injection molding, high-temperature melt-blending molding or compression-sintering molding.

[0031] The method and conditions of the injection molding may be conventional method and conditions in the art. The injection molding is preferably performed in an injection-molding machine. The temperature of the injection molding is preferably 260°C to 280°C. The pressure of the injection molding is preferably 100 MPa to 120 MPa.

[0032] In such a case, the method and conditions of the high-temperature melt blending molding may be conventional method and conditions in the art. The high temperature melt-blending molding is preferably performed in a twin-screw extruder. The temperature of the high-temperature melt-blending molding is preferably 260 °C to 280°C. The pressure of the high-temperature melt-blending molding is preferably 80 MPa to 100 MPa.

[0033] In such a case, the method and conditions of the compression-sintering molding may be conventional method and conditions in the art. The compression sintering molding is preferably performed as the following operation method: subjecting the mixed powder to compression molding, then heating, and sintering molding. The heating rate is preferably 1 C/min to 2 °C/min. The temperature of the sintering is preferably 260 °C to 280 °C. The temperature-holding time of the sintering is preferably 3 h to 4 h, preferably 3 h.

[0034] In the present disclosure, in the preparation method for a bone prosthesis, after the molding, a surface treatment by sandblasting is preferably performed. The operation of the surface treatment by sandblasting may be a conventional operation in the art, and is preferably performed as the following step: surface sandblasting the molded block with sand with a particle size of 20 m to 50 m using a surface sandblasting machine until the surface of the block forms a porous surface with a pore size of 50 m to 100 [m. The molded block refers to a block obtained by means of injection molding, high-temperature melt-blending molding or compression-sintering molding.

[0035] In the present disclosure, in the preparation method for a bone prosthesis, after the molding, a surface treatment by sulfonation is preferably performed. The operation of the surface treatment by sulfonation may be a conventional operation in the art, and is preferably performed as the following step: subjecting the molded block to a soaking treatment with 90% to 98% concentrated sulfuric acid, and then to a hydrothermal treatment at 110C to 130C until the surface of the block forms a porous surface with a pore size of 1 m to 10 m, the above percentage being a volume percentage. In such a case, with the temperature of the hydrothermal treatment being preferably 120 C.

[0036] The present disclosure further provides a bone prosthesis prepared and obtained by the above preparation method.

Our Ref.: P20455525AU

[0037] In such a case, the bone prosthesis is a spinal bone prosthesis or a dental implant. The spinal bone prosthesis is also referred to as an intervertebral fusion cage, including a cervical intervertebral fusion cage and a thoracic/lumbar intervertebral fusion cage.

[0038] In the present disclosure, the shape and the specification of the bone prosthesis may be changed by means of selecting different molds according to actual needs.

[0039] In the present disclosure, the criteria of mechanical properties of the composite material or the bone prosthesis are generally as follows: the modulus of elasticity is 4.1 GPa to 6.2 GPa, the compressive strength is 121 MPa to 162 GPa, the tensile strength is 80 MPa to 93 MPa, and the bending strength is 65 MPa to 82 MPa.

[0040] On the basis of meeting common knowledge in the art, the above-mentioned various preferred conditions can be combined in any form, such that various preferred examples of the present disclosure are obtained.

[0041] The reagents and raw materials used in the present disclosure are commercially available.

[0042] The present disclosure has the positive improvement effects as follows:

(1) the process of the LAP/PI composite material of the present disclosure is simple and feasible, and the process for preparing the LAP/PI composite material can be adjusted according to clinical needs to prepare bone prostheses of different shapes, specifications and mechanical properties.

(2) The surface sandblasting technique is used for treating the surface of the composite material molded body to form a rough porous structure in the surface of the composite material, such that osteocytes/bone tissues and blood vessels easily grow into pores of the multiple pores so as to enable the bone tissue to form a firm binding with the implant.

(3) The surface sulfonation technique is used for treating the surface of the composite material molded body to form a rough porous structure in the surface of the composite material, such that osteocytes/bone tissue and blood vessels easily grow into the pores of the multiple pores so as to enable the bone tissue to form a firm binding with the implant; in addition, the surface-grafted sulfonic acid groups endows the surface of the implant with certain antibacterial properties.

(4) The LAP/PI composite material of the present disclosure has good bioactivity and biocompatibility with bone, has good mechanical compatibility with the bone tissue, and can stimulate the bone growth, accelerate the bone healing, and reduce the healing time after the implementation of a material into the bone tissue.

(5) The bone prosthesis of the present disclosure has good biocompatibility, bioactivity, and mechanical compatibility of bone, and can shorten the bone healing time. The bone prosthesis will not cause inflammation after being implanted, and has the modulus of elasticity, the toughness, the breaking strength and other mechanical properties matching human bone, which will not cause loosening of the bone repair material due

Our Ref.: P20455525AU

to stress shielding and the negative effect such as bone resorption, and can promote the regeneration of surrounding bone tissue and the fusion with natural bone tissue after being implanted, which can meet the postoperative requirements of immediate fixation and long-term stability of orthopedic instruments.

Brief description of the drawings

[0043] Fig. 1 shows the shape images (D12 x 2 mm) of a PI material, and LAP/P composite materials of Examples 1 to 2, in which a shows the PI material, b shows the LAP/PI composite material of Example 1, and c shows the LAP/PI composite material of Example 2.

[0044] Fig. 2 shows the scanning electron microscope (SEM) images of the PI material, and the LAP/PI composite materials of Examples 1to 2, in which a and b show the PI material, c and d show the LAP/PI composite material of Example 1, and e and f show the LAP/PI composite material of Example 2.

[0045] Fig. 3 shows the scanning electron microscope (SEM) images of the sandblasting-treated PI material and the LAP/PI composite material of Example 2, in which a shows an SEM image of the sandblasted PI material; and b shows an SEM image of the LAP/PI composite material of Example 2.

[0046] Fig. 4 shows the scanning electron microscope (SEM) images of an LAP/P composite material of Example 10, in which a shows an SEM image with a scale of 4 im, and b shows an SEM image with a scale of 20 m.

[0047] Fig. 5 shows a chart of data of water contact angle of the PI material and the LAP/PI composite materials of Examples 1 to 2.

[0048] Fig. 6 shows the scanning electron microscope (SEM) images of the PI material and the LAP/PI composite materials of Examples 1 to 2, with apatite deposited on the surface, after an in vitro bioactivity experiment, in which Fig. 6a shows a surface effect image of the PI material, Fig. 6b shows a surface effect image of the LAP/P composite material of Example 1, and Fig. 6c shows a surface effect image of the LAP/PI composite material of Example 2.

[0049] Fig. 7 shows an EDS analysis spectrogram of the surface deposit of the LAP/P composite material of Example 2 after the in vitro bioactivity experiment.

[0050] Fig. 8 is a chart of optical density data of the LAP/PI composite materials of Examples 1 and 4 and a TCP control group obtained from the cytotoxicity test.

[0051] Fig. 9 is a chart of optical density data, measured at different culture time points, of the LAP/PI composite materials of Examples 1 to 2 and the PI material during a cell adhesion and proliferation test.

[0052] Fig. 10 shows the scanning electron microscope (SEM) images of cell adhesion of the LAP/PI composite materials of Examples 1 to 2 and the PI material in the cell adhesion and proliferation test after the cells are fixed with a fixative solution

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at different time points, in which Fig. 10a shows the cell adhesion of 12 h of the PI material, Fig. 10b shows the cell adhesion of 12 h of the LAP/PI composite material of Example 1, Fig. 10c shows the cell adhesion of 12 h of the LAP/PI composite material of Example 2, Fig. 10d shows the cell adhesion of 24 h of the PI material, Fig. 10e shows the cell adhesion of 24 h of the LAP/PI composite material of Example 1, and Fig. 10f shows the cell adhesion of 24 h of the LAP/PI composite material of Example 2.

[0053] Fig. 11 shows a diagram of comparison in ALP activity of the LAP/PI composite materials of Examples 1 to 2 and the PI material in a cell differentiation test.

Detailed description of the preferred embodiment

[0054] The present disclosure is further illustrated by the following example, but the present disclosure is not limited thereto. Experimental methods with specific conditions are not indicated in the following examples, but can be chosen according to conventional methods and conditions or commodity instructions.

[0055] In the following examples and comparative examples, the methods for preparing a laponite powder are all as follows:

(1) placing laponite (Model LAPONITE-RDS purchased fromAltana AG in Germany) in a muffle furnace for sintering, with the sintering temperature of 1000 °C, the sintering time of 3 h, and the heating rate of 3.5 °C/min for reaching the sintering temperature; and

(2) ball-milling the laponite, after high-temperature sintering, with a ball mill (at a rotation speed of 500 r/min) for 24 h to obtain a laponite powder with a particle size of 2 to 3 pm.

[0056] In the following examples and comparative examples, the polyimide is Model M1 purchased from Changzhou Junhua Special Engineering Plastic Products Co., Ltd. The mixer is a commercially available product, Model SYH-2, of Changzhou Saiwei Machinery Manufacturing Co., Ltd.

[0057] Example 1

[0058] A preparation method for a laponite/polyimide composite material, the method comprising the following steps:

[0059] uniformly mixing 2 kg (20 wt.%) of a laponite powder (with a particle size of 2 to 3 m) after a high-temperature treatment and 8 kg (80 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer (at a rotation speed of 600 r/min for a mixing time of 12 h) to obtain a mixed powder; and injection molding the mixed powder with an injection-molding machine (with a mold not for bone prosthesis products) so as to obtain a laponite/polyimide composite material (an LAP/PI composite material), wherein the temperature during the injection molding is 280 °C; and the pressure during the injection molding is 100 MPa.

our Ref.: P20455525AU

[0060] Example 2

[0061] A preparation method for a laponite/polyimide composite material, the method comprising the following steps:

[0062] uniformly mixing the raw materials, including 4 kg (40 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 6 kg (60 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer (at a rotation speed of 600 r/min for a mixing time of 12 h) to obtain a mixed powder; and injection molding the mixed powder with an injection-molding machine (with a mold not for bone prosthesis products) so as to obtain a laponite/polyimide composite material (an LAP/PI composite material), wherein the temperature during the injection molding is 280°C; and the pressure during the injection molding is 120 MPa.

[0063] The laponite/polyimide composite material of Example 2 is subjected to an operation of a surface treatment by sandblasting, specifically as follows: surface sandblasting the molded block with sand using a surface sandblasting machine until the surface of the block forms a porous surface with a pore size of 50 m to 100 m so as to obtain a bone prosthesis, wherein the sand has a particle size of 20 m to 50 m.

[0064] Example 3

[0065] A preparation method for a laponite/polyimide composite material, the method comprising the following steps:

[0066] uniformly mixing the raw materials, including 2 kg (20 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 8 kg (80 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer (at a rotation speed of 600 r/min for a mixing time of 12 h) to obtain a mixed powder; and then extrusion molding the mixed powder with a twin-screw extruder (with a mold not for bone prosthesis products) so as to obtain a laponite/polyimide composite material (an LAP/PI composite material), wherein the temperature during the extrusion molding is 280°C; and the pressure during the extrusion molding is 80 MPa.

[0067] Example 4

[0068] A preparation method for a laponite/polyimide composite material, the method comprising the following steps:

[0069] uniformly mixing the raw materials, including 4 kg (40 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 6 kg (60 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer (at a rotation speed of 600 r/min for a mixing time of 12 h) to obtain a mixed powder; and then compression molding the mixed powder with a mold (with a mold not for bone prosthesis products), and then heating in a muffle furnace for sintering molding so as to obtain a laponite/polyimide composite material (an LAP/PI composite material), wherein the sintering temperature is 280°C; the heating rate in the muffle furnace is 2°C/min; and the temperature-holding time is 180 minutes.

our Ref.: P20455525AU

[0070] Example 5

[0071] A preparation method for a laponite/polyimide composite material, the method comprising the following steps:

[0072] uniformly mixing the raw materials, including 1.5 kg (15 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 8.5 kg (85 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer to obtain a mixed powder; and then compression molding the mixed powder with a mold (with a mold not for bone prosthesis products), and then heating in a muffle furnace for sintering molding so as to obtain a laponite/polyimide composite material (an LAP/PI composite material), wherein the sintering temperature is 280°C; the heating rate in the muffle furnace is 2 °C/min; and the temperature-holding time is 180 minutes.

[0073] Example 6

[0074] A preparation method for a laponite/polyimide composite material, the method comprising the following steps:

[0075] uniformly mixing the raw materials, including 3 kg (30 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 7 kg (70 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer to obtain a mixed powder; and then compression molding the mixed powder with a mold (with a mold not for bone prosthesis products), and then heating in a muffle furnace for sintering molding so as to obtain a laponite/polyimide composite material (an LAP/PI composite material), wherein the sintering temperature is 280°C; the heating rate in the muffle furnace is 2 °C/min; and the temperature-holding time is 180 minutes.

[0076] Example 7

[0077] A preparation method for a bone prosthesis, the method comprising the following steps:

[0078] uniformly mixing the raw materials, including 2 kg (20 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 8 kg (80 wt.%) of a polyimide powder (with a particle size of 12 to 18 m) in a mixer (at a rotation speed of 600 r/min for a mixing time of 12 h) to obtain a mixed powder; and then injection molding the mixed powder by means of an injection-molding machine in a mold for rabbit femoral prostheses so as to obtain a laponite/polyimide bone prosthesis (an LAP/PI bone prosthesis), wherein the temperature during the injection molding is 280 °C; and the pressure during the injection molding is 100 MPa.

[0079] Example 8

[0080] A preparation method for a bone prosthesis, the method comprising the following steps:

[0081] uniformly mixing the raw materials, including 4 kg (40 wt.%) of a laponite powder (with a particle size of 2 to 3 m) and 6 kg (40 wt.%) of a polyimide powder

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(with a particle size of 12 to 18 m) in a mixer (at a rotation speed of 600 r/min for a mixing time of 12 h) to obtain a mixed powder; and then compression molding the mixed powder with a mold (with a mold not for bone prosthesis products), and then heating in a muffle furnace for sintering molding so as to obtain a laponite/polyimide bone prosthesis (an LAP/PI bone prosthesis), wherein the sintering temperature is 280 °C; the heating rate in the muffle furnace is 2°C/min; and the temperature-holding time is 180 minutes.

[0082] Example 9

[0083] A preparation method for a bone prosthesis, the method comprising the following steps:

[0084] performing operation according to the raw material formulation and the preparation method of Example 1, and after the injection molding in a mold for rabbit femoral prostheses, performing operation of a surface treatment by sandblasting, specifically as follows: surface sandblasting the molded block with sand using a surface sandblasting machine until the surface of the block forms a porous surface with a pore size of 50 m to 100 m so as to obtain a bone prosthesis, wherein the sand has a particle size of 20 m to 50 m.

[0085] Example 10

[0086] A preparation method for a bone prosthesis, the method comprising the following steps:

[0087] performing operation according to the raw material formulation and the preparation method of Example 2, and after the injection molding in a mold for rabbit femoral prostheses, performing operation of a surface treatment by sulfonation, specifically as follows: subjecting the molded block to a soaking treatment with 98% concentrated sulfuric acid, and then to a hydrothermal treatment at 120 °C. The soaking time is 20 min, and the hydrothermal treatment time is 4 h.

[0088] Comparative example 1

[0089] providing 1 kg of a laponite powder (with a particle size of 2 to 3 m) and 9 kg of a polyimide powder (with a particle size of 12 to 18 m), and preparing a composite material according to the preparation method of Example 1.

[0090] Comparative example 2

[0091] providing 5 kg of a laponite powder (with a particle size of 2 to 3 m) and 5 kg of a polyimide powder (with a particle size of 12 to 18 m), and preparing a composite material according to the preparation method of Example 1.

[0092] Comparative example 3

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[0093] providing 6 kg of a laponite powder (with a particle size of 2 to 3 m) and 4 kg of a polyimide powder (with a particle size of 12 to 18 m), and preparing a composite material according to the preparation method of Example 1.

[0094] Comparative example 4

[0095] providing 4 kg of a laponite powder (with a particle size 20 m) and 6 kg of a polyimide powder (with a particle size of 12 to 18 m), and preparing a composite material according to the preparation method of Example 1.

[0096] Effect example 1

[0097] Fig. 1 shows the shape images (CD12 x 2 mm) of a PI material, and LAP/PI composite materials of Examples 1 to 2, in which a shows the PI material, b shows the LAP/PI composite material of Example 1, and c shows the LAP/PI composite material of Example 2. In such a case, the samples to be tested of the LAP/PI composite materials of Examples 1 to 2 (the wafer being obtained by cutting the composite materials of Examples 1 to 2) and the control group (the PI material) are wafers of the same specification with a diameter of 12 mm and a thickness of 2 mm. The preparation method for the control group (PI material) is as follows: compression molding the PI powder (the type of the PI powder is the same as that in Example 1), and then heating same for sintering molding, with the heating rate being preferably 1 °C/min, the temperature during the sintering being 270°C, and the temperature-holding time during the sintering being 3 h.

[0098] Fig. 2 shows the scanning electron microscope (SEM) images of the PI material, and the LAP/PI composite materials of Examples 1to 2, in which a and b show the PI material, c and d show the LAP/PI composite material of Example 1, and e and f show the LAP/PI composite material of Example 2. In such a case, the samples to be tested of the LAP/PI composite materials of Examples 1 to 2 and the control group (the PI material) are wafers of the same specification, with a diameter of 12 mm and a thickness of 2 mm; the preparation method for the PI material of the control group is the same as described above, and the wafers of Examples 1 to 2 are obtained by cutting the composite materials of Examples 1 to 2.

[0099] Fig. 3 shows the scanning electron microscope (SEM) images of the sandblasting-treated PI material and the LAP/PI composite material of Example 2, in which a shows an SEM image of the sandblasted PI material; and b shows an SEM image of the LAP/PI composite material of Example 2. In such a case, the samples to be tested of the LAP/PI composite material of Example 2 and the control group (the PI material) are wafers of the same specification, with a diameter of 12 mm and a thickness of 2 mm; the preparation method for the PI material of the control group is the same as described above, the wafers of Example 2 are obtained by cutting the composite material of Example 2, and the sandblasting treatment process of the PI material is the same as that of Example 2.

Our Ref.: P20455525AU

[0100] Fig. 4 shows the scanning electron microscope (SEM) images of an LAP/PI composite material of Example 10, in which a shows an SEM image with a scale of 4

[tm, and b shows an SEM image with a scale of 20 m.

[0101] The PI material and the LAP/PI composite materials of Examples 1 to 2 are tested for hydrophilicity, and the specific test method is as follows: dropping a drop of water (estimated as 0.5 mL) on a wafer, measuring the contact angle thereof (the manufacturer of the instrument for measuring a contact angle: Shanghai Zhongchen Digital Technic Apparatus Co., Ltd., the model: 0 to 180 degrees, 0.1 or 0.5/JC2000D2). The preparation method for the PI material of the control group is the same as described above, and the wafers of Examples 1 to 2 are obtained by cutting the composite materials of Examples 1 to 2. Fig. 5 shows a chart of data of water contact angle of the PI material and the LAP/PI composite materials of Examples 1 to 2; it can be seen from Fig. 5 that the water contact angle of the PI material is 78 ±2.5 °, the water contact angle of the LAP/PI composite material of Example 1 is 65.5 ±0.8° and the water contact angle of the LAP/PI composite material of Example 2 is 50.5 1.5 °. It can be seen therefrom that the composite material prepared by the examples of the present application has significantly improved hydrophilicity, the composite material has better hydrophilicity, and accordingly, will have better cell adhesion.

[0102] Effectexample2

[0103] Mechanical property experiment:

[0104] The LAP/PI composite materials of Examples 1 to 6 and Compressive examples 1 to 4, and the bone prostheses of Examples 7 to 8 are subjected to a mechanical property test, and the test results are shown in Table 1 and Table 2. The test standard of modulus of elasticity is IS0527, the test standard of compressive strength is IS0527, the test standard of tensile strength is GB/T228.1-2010, and the test standard of bending strength is GB/T 6569-86.

[0105] In Table 1 and Table 2, for the modulus of elasticity, the LAP/PI composite materials of Examples 1 to 6 and the Comparative examples 1 to 4, and the bone prostheses of Examples 7 to 8 are prepared as cylindrical samples with a diameter of 12 mm and a height of 25 mm, the test is performed with a universal tensile testing machine, and calculation is performed according to a stress-strain curve. For the compressive strength, the LAP/PI composite materials of Examples 1 to 6 and the Comparative examples 1to 4, and the bone prostheses of Examples 7 to 8 are prepared as cylindrical samples with a diameter of 12 mm and a height of 10 mm, and the test is performed with a universal tensile testing machine. For the tensile strength, the LAP/PI composite materials of Examples 1 to 6 and Comparative examples 1 to 4, and the bone prostheses of Examples 7 to 8 are prepared as dumbbell-shaped samples (with a length of 150 mm, a width of 10 mm, and a thickness of 3 mm), and the test is performed with a universal tensile testing machine. For the bending strength, the LAP/PI composite materials of Examples 1 to 6 and Comparative examples 1 to 4, and the bone prostheses of Examples 7 to 8 are prepared as dumbbell- samples (with a

Our Ref.: P20455525AU

length of 80 mm, a width of 10 mm, and a thickness of 4 mm), and the test is performed with a universal tensile testing machine. The above universal tensile testing machines are all purchased from Shenzhen SANS testing machine Co., Ltd, Model 2T/CMT 4204.

Table 1 Results of mechanical property test of the LAP/PI composite materials of Examples 1 to 6 and the bone prostheses of Examples 7 to 8

No. Examp Examp Examp Examp Examp Examp Examp Examp Criteria le 1 le 2 le 3 le 4 le 5 le 6 le 7 le 8

Modulus of elasticity 4.2 6.2 4.3 5.0 4.1 4.6 4.3 5.2 (GPa) Compressive strength 122.2 162.2 126.8 136.1 121.2 130.8 123.1 138.2 (MPa) Tensile strength 81.3 92.3 82.8 86.1 80.2 84.2 81.9 86.7 (MPa) Bending strength 70.5 81.4 67.9 79.2 65.4 76.9 70.6 79.9 (MPa)

[0106] Table 2 The results of mechanical property test for the LAP/PI composite material of Comparative examples 1 to 4 and human bone

No. Comparative Comparative Comparative Comparative Human Criteria example 1 example 2 example 3 example 4 bone

Modulus of 2.3 2.9 6.2 2.4 3 to 8 elasticity (GPa) Compressive 81.6 126.7 129.9 115.4 130 to strength (MPa) 180 Tensile strength 68.4 72.6 69.1 76.3 87 (MPa) Bending 62.3 73.7 75.3 60.2 78 strength (MPa)

[0107] It can be seen from Table 1 and Table 2 that compared with the composite materials prepared in Comparative examples 1 to 4, the LAP/PI composite materials or the bone prostheses of the present disclosure have the modulus of elasticity closer to that of human bone, and have better criteria of parameters in mechanical properties, and are very suitable as substitute materials for human hard tissues (bone and teeth).

[0108] Effectexample3

[0109] The LAP/PI composite materials of Examples 1 to 2 are subjected to in vitro bioactivity experiment. In the in vitro bioactivity experiment, the samples to be tested

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of the LAP/PI composite materials of Examples 1 to 2 and the control group (PI material) are wafers (the wafers of Examples 1 to 2 are obtained by cutting) of the same specification with a diameter of 12 mm and a thickness of2 mm; the preparation method for the PI material of the control group is the same as the preparation method in Effect example 1.

[0110] The specific method of the in vitro bioactivity experiment is as follows:

[0111] the LAP/PI composite material is soaked in a centrifuge tube containing 10 mL of an SBF solution. Then it is placed in a constant-temperature oscillation incubator at 37°C, and sampled after soaking for 7 days. The surface is gently rinsed with deionized water and then oven-dried. The formation and microscopic morphology of apatite on the surface of the sample to be tested are observed by an SEM electron microscope. The composition of the substance formed on the surface of the LAP/PI composite material of Example 2 is measured by EDS. The PI material without laponite added is used as the control group.

[0112] Fig. 6 shows the scanning electron microscope (SEM) images of the PI material and the LAP/PI composite materials of Examples 1 to 2, with apatite deposited on the surface, after an in vitro bioactivity experiment, in which Fig. 6a shows a surface effect image of the PI material, Fig. 6b shows a surface effect image of the LAP/PI composite material of Example 1, and Fig. 6c shows a surface effect image of the LAP/PI composite material of Example 2. It can be seen from Fig. 6 that, in Fig. 6a, no apatite deposit is observed on the surface of the PI material after soaking; in Fig. 6b, there are more apatite deposits on the surface of the LAP/PI composite material of Example 1; and in Fig. 6c, there are the largest amount of apatite deposits on the surface of the LAP/PI composite material of Example 2.

[0113] Fig. 7 shows anEDS analysis spectrogram of the surface deposit of the LAP/PI composite material of Example 2 after the in vitro bioactivity experiment. It can be seen from Fig. 7 that the surface thereof contains calcium and phosphorus ions, so the composition of the deposit is determined to be apatite.

[0114] This Effect example 1 shows that the composite material prepared and obtained in the present disclosure has good bioactivity.

[0115] Effectexample4

[0116] The LAP/PI composite materials of Example 1 and Example 4 is subjected to a cytotoxicity test. In the cytotoxicity test, the samples to be tested of the LAP/PI composite materials of Example 1 and Example 4 and the blank control (a tissue culture plate, TCP) are all wafers (the wafers from Examples 1 and 4 are obtained by cutting) of the same specification with a diameter of 12 mm and a thickness of 2 mm.

[0117] The specific method of the cytotoxicity testis as follows:

[0118] the biological safety of the composite material is tested according to ISO:10993-5 Cytotoxicity. At 37 °C, two samples are each soaked in a serum-free cell

Our Ref.: P20455525AU

culture medium (200 mg/mL) for 24 hours, and filtered to obtain an extract. A 96 well tissue culture plate is inoculated with fibroblasts at a concentration of 3 x 10 2/well and further incubated for 1 day, then the culture medium is discarded, and the culture plate is washed with PBS 3 times; the culture plate is added with an extract containing % FBS, and further cultured for 1 day; and the medium without addition of the material extract containing 10% FBS is used as the blank control group. At the test time point, the following steps are performed: adding 30 microliters of an MTT solution to each well and further inoculating for 4 hours, discarding the culture solution, washing with PBS 3 times, adding 100 microliters of DMSO to each well, standing at room temperature for 10 minutes, and then measuring the optical density of the solution with a microplate reader at a wavelength of 490 nm, as shown in Fig. 8.

[0119] Fig. 8 is a chart of optical density data of the LAP/PI composite materials of Examples 1 and 4 and a TCP control group obtained from the cytotoxicity test. It can be seen from Fig. 8 that, compared with the blank control (the tissue culture plate, TCP), the optical density of the test groups (the LAP/PI composite materials of Example 1 and Example 4) has no significant difference, which indicates that the two composite materials have no negative effect on the growth of fibroblasts. It can be known by calculation that, the percents of the survival rate of the cells in the extracts of the LAP/PI composite materials of Example 1 and Example 4 to the survival rate of the cells in the blank control group are both no less than 95%, which proves that the two samples have no toxicity on fibroblasts.

[0120] As shown in Fig. 8, the values of the optical density of the LAP/PI composite materials of Example 1 and Example 4 and the TCP control group in the cytotoxicity test are respectively 0.48 ±0.008, 0.52 ±0.01 and 0.5 ±0.019.

[0121] Effectexample5

[0122] A cell adhesion and proliferation test is performed for the LAP/PI composite materials of Examples 1 to 2. In the cell adhesion and proliferation test, the samples to be tested of the LAP/PI composite materials of Examples 1 to 2 and the control group (PI material) are wafers (the wafers of Examples 1 to 2 are obtained by cutting) of the same specification with a diameter of 12 mm and a thickness of 2 mm; the preparation method for the PI material of the control group is the same as the preparation method in Effect example 1.

[0123] The specific method of the cell adhesion and proliferation testis as follows:

(1) A cell proliferation testis performed by means of a CCK8 method. Beforethe cell inoculation, the sample to be tested is sterilized with ethylene oxide and placed in a 24-well plate, and then the material is inoculated with BMSCs cells as 1 x 104 cells/mL. During the culture, the cell culture solution is replaced every two days, and at the corresponding time points of day 1, day 3 and day 7 of the cell culture, the material is taken out, placed in a new 24-well plate, added with 500 L of a CCK8 reagent, placed back to the culture incubator, and cultured for 4 hours, and then 100 L of the culture solution is added to a 96-well plate, and the corresponding optical density our Ref.: P20455525AU is measured with a microplate reader at 490 nm. The PI material without laponite added is used as the control group.

[0124] Fig. 9 is a chart of optical density data, measured at different culture time points, of the LAP/PI composite materials of Examples 1 to 2 and the PI material during a cell adhesion and proliferation test. It can be seen from Fig. 9 that, the LAP/PI composite material of Example 2 has the largest optical density and accordingly has the highest cell adhesion and proliferation capability, followed by the LAP/PI composite material of Example 1, and the PI material has the smallest optical density and accordingly has the lowest cell adhesion and proliferation capability.

[0125] In Fig. 9, the values of optical density of the LAP/PI composite materials of Examples 1 to 2 and the PI material at different culture time points are as shown in Table 3.

Table 3

Data Optical density

Classification Day 1 Day 3 Day 7

Polyimide 0.13 ±0.04 0.29 0.02 0.71 ±0.08

Example 1 0.25 ±0.03 0.5 0.01 1.13 ±0.05

Example 2 0.39 ±0.02 0.8 0.03 1.41 ±0.03

(2) The surface of the composite sample is inoculated with BMSCs cells at a density of 1 X 104 cells per well, and at 12 h and 24 h, the cells are fixed with a fixative solution, and then the cell adhesion is observed under a scanning electron microscope.

[0126] Fig. 10 shows the scanning electron microscope (SEM) images of cell adhesion of the LAP/PI composite materials of Examples 1 to 2 and the PI material in the cell adhesion and proliferation test after the cells are fixed with a fixative solution at different time points, in which Fig. 10a shows the cell adhesion of 12 h of the PI material, Fig. 10b shows the cell adhesion of 12 h of the LAP/PI composite material of Example 1, Fig. 10c shows the cell adhesion of 12 h of the LAP/PI composite material of Example 2, Fig. 10d shows the cell adhesion of 24 h of the PI material, Fig. l0e shows the cell adhesion of 24 h of the LAP/PI composite material of Example 1, and Fig. 10f shows the cell adhesion of 24 h of the LAP/PI composite material of Example 2. It can be seen from Fig. 10 that the surfaces of the LAP/PI composite materials of Examples 1 to 2 both have cell adhesion and proliferation, and the LAP/PI composite material group of Example 2 has a larger number of adhered cells and a better adhesion morphology, which indicates that it has better cell compatibility.

[0127] Effect example 6

[0128] The LAP/PI composite materials of Examples 1to 2 is subjected to a cell differentiation experiment. In the cell differentiation experiment, the samples to be our Ref.: P20455525AU tested of the LAP/PI composite materials of Examples 1 to 2 and the control group (PI material) are wafers (the wafers of Examples 1 to 2 are obtained by cutting) of the same specification with a diameter of 12 mm and a thickness of2 mm; the preparation method for the PI material of the control group is the same as the preparation method in Effect example 1.

[0129] The specific method of the cell differentiation experiment is as follows:

[0130] an alkaline phosphatase (ALP) test kit is used to study the differentiation of cells on the material. The samples are sterilized with ethylene oxide and then placed in a 24-well plate, and the surface of the material is inoculated with BMSCs cells as 2.5 x 104 cells/mL. The differentiation of cells on the surface of the material is observed by ALP staining at day 7, day 10 and day 14 of the culture, with the cell culture solution being replaced every two days during the cell culture. At the corresponding time points, the culture medium in the well plate is removed, and then the well plate is washed with a PBS buffer three times.

[0131] 500 pL of a 1% ethyl phenyl polyethylene glycol solution is added to the wells where the material is placed so as to obtain a cell lysate. After the lysis is complete, pL of a 1 mg/mL P-nitrophenyl phosphate solution is added to each well, and after minutes at room temperature, 100 L of 0.1 M NaOH solution is added to terminate the reaction. Finally, the OD values in the wells are measured with a microplate reader at a wavelength of 405 nm, and the ALP activity of the cells is calculated according to the OD values. The PI material without laponite added is used as the control group.

[0132] Fig. 11 shows a diagram of comparison in ALP activity of the LAP/PI composite materials of Examples 1 to 2 and the PI material in a cell differentiation test. It can be seen from Fig. 11 that, as the cell culture time increases, the ALP activity of the cells on the three samples to be tested gradually increases. In general, the LAP/PI composite material of Example 2 has the highest cell differentiation activity, followed by the LAP/PI composite material of Example 1, and the PI material has the lowest cell differentiation activity. Therefore, with the addition of laponite, the composite material has a good promoting effect on cell differentiation.

[0133] In Fig. 11, the data of ALP activity of the LAP/PI composite materials of Examples 1 to 2 and the PI material at different culture times in the cell differentiation experiment are as shown in Table 4.

Table 4

Data ALP activity

Classification Day 7 Day 10 Day 14

Polyimide 2.5 ±0.12 4.9 ±0.24 5.3 ±0.15

Example 1 3.7 ±0.25 5.2 ±0.27 9.1 ±0.21

Example 2 6.1 ± 0.23 9.2 ± 0.21 13.4 ± 0.26

Claims

OurRef.: P20455525AU CLAIMS:

1. A raw material composition of a composite material, wherein the raw material composition comprises the following components: a laponite powder and a polyimide powder, wherein the laponite powder and the polyimide powder are in a mass ratio of (1 to 2):(3 to 4), and the laponite powder has a particle size of 1 m to 10 im.

2. The raw material composition as defined in claim 1, wherein the laponite powder has a mass fraction of 15% to 40%, the polyimide powder has a mass fraction of60% to 85%, and preferably, the laponite powder has a mass fraction of 20% to 30%, and the polyimide powder has a mass fraction of 70% to 80%, the above percentages being mass percentages of the components relative to the raw material composition of the composite material;

and/or the laponite powder is prepared and obtained by the following steps: sintering and then ball-milling the raw material laponite;

and/or the laponite powder has a particle size of 2 pm to 5 im, preferably 2 to 3

and/or the polyimide is thermoplastic aromatic polyimide, preferably one or more of pyromellitic dianhydride type polyimide, ether-anhydride type polyimide and ketone-anhydride type polyimide, more preferably Model M1 purchased from Changzhou Junhua Special Engineering Plastic Products Co., Ltd.;

and/or the polyimide powder has a particle size of 10 pm to 20 im, preferably 12 pm to 18 im, more preferably 15 pm.

3. The raw material composition as defined in claim 2, wherein the raw material laponite is Model LAPONITE-RDS purchased from Altana AG in Germany;

and/or the sintering is performed in a muffle furnace; the temperature of the sintering is preferably 900 °C to 1100 °C, more preferably 1000 °C; the time of the sintering is preferably 3 to 4 hours; in order to reach the temperature of the sintering, a heating rate is preferably 2 °C/min to 5 °C/min, more preferably 3.5 °C/min;

and/or the ball-milling is performed by means of a ball mill; the rotation speed of the ball mill is preferably 450 to 550 r/min, and is more preferably 500 r/min; and the time of the ball-milling is preferably 20 to 30 hours, more preferably 24 hours.

4. A preparation method for a laponite/polyimide composite material, wherein the method comprises the following step: molding the raw material composition as defined in any one of claims I to 3.

5. The preparation method as defined in claim 4, wherein the molding includes injection molding, high-temperature melt-blending molding, or compression-sintering molding;

the injection molding is preferably performed in an injection-molding machine; the

OurRef.: P20455525AU

temperature of the injection molding is preferably 260 C to 280 °C; the pressure of the injection molding is preferably 100 MPa to 120 MPa;

the high-temperature melt-blending molding is preferably performed in a twin screw extruder; the temperature of the high-temperature melt-blending molding is preferably 260 C to 280 °C; the pressure of the high-temperature melt-blending molding is preferably 80 MPa to 100 MPa;

the compression-sintering molding is preferably performed as the following operation method: subjecting the mixed powder to compression molding, then heating, and sintering molding; the heating rate is preferably 1C/min to 2 °C/min; the temperature of the sintering is preferably 260 °C to 280 °C; and the temperature-holding time of the sintering is preferably 3 h to 4 h, more preferably 3 h.

6. A laponite/polyimide composite material prepared and obtained by the preparation method as defined in claim 4 or 5.

7. Use of the laponite/polyimide composite material as defined in claim 6 in a bone prosthesis, wherein the bone prosthesis is preferably a spinal bone prosthesis or a dental implant; and the spinal bone prosthesis preferably comprises a cervical intervertebral fusion cage and a thoracic/lumbar intervertebral fusion cage.

8. A preparation method for a bone prosthesis, the method comprising the following step: molding the raw material composition as defined in any one of claims 1 to 3 in a bone prosthesis product mold.

9. The preparation method as defined in claim 8, wherein the bone prosthesis product mold is a spinal bone prosthesis mold or a dental implant mold; the spinal bone prosthesis preferably comprises a cervical intervertebral fusion cage and a thoracic/lumbar intervertebral fusion cage;

and/or the operations and conditions of the molding are the molding conditions for the raw material composition as defined in claim 5;

and/or in the preparation method for a bone prosthesis, the molded block is further subjected to a surface treatment by sandblasting; the surface treatment by sandblasting is preferably operated as the following step: surface sandblasting the molded block with sand having a particle size of 20 pm to 50 pm using a surface sandblasting machine until the surface of the block forms a porous surface with a pore size of 50 pm to 100 pIm;

and/or in the preparation method for a bone prosthesis, the molded block is further subjected to a surface treatment by sulfonation; the surface treatment by sulfonation is preferably operated as the following step: subjecting the molded block to a soaking treatment with 90% to 98% concentrated sulfuric acid, then to a hydrothermal treatment at 110 °C to 130 °C until the surface of the block forms a porous surface with a pore size of 1 m to 10 m, the above percentage being a volume percentage, with the temperature of the hydrothermal treatment being preferably 120 °C.

OurRef.: P20455525AU

10. A bone prosthesis prepared and obtained by the preparation method as defined in claim 8 or 9.