Silicone rubber plate for bone cement mixing and preparation process therefor

Abstract

The present invention discloses a silicone rubber plate for bone cement mixing and a preparation process therefor, relating to the technical field of silicone rubber plates. The preparation process comprises the following steps: adding silicone rubber, fluorosilicone rubber, and a bis-sulfur vulcanizing agent into a kneader, adjusting the roll gap, forming sheets, and vulcanizing to obtain a silicone rubber raw sheet; cutting and molding the silicone rubber raw sheet, performing ultrasonic cleaning in ethanol, and setting aside for later use; sequentially treating the surface of the cleaned silicone rubber raw sheet with a nanosecond laser and performing laser drilling treatment with a picosecond laser, then preparing nano-silica by means of hydrolysis and condensation of ethyl silicate and filling the holes with same, cleaning the surface other than the drilled regions with a picosecond laser, and finally performing hydrophobic modification with hexamethyldisilazane to obtain a superhydrophobic silicone rubber plate; performing mercapto modification on the surface of the superhydrophobic silicone rubber plate, grafting ammonium bromide on the surface thereof by means of a UV light-induced thiol-ene reaction, then grafting by means of an L-proline reaction, and finally absorbing nitric oxide to saturation to obtain the silicone rubber plate for bone cement mixing.

Description

A silicone rubber sheet for bone cement mixing and its preparation process Technical Field

[0001] This invention relates to the field of silicone rubber sheet technology, specifically a silicone rubber sheet for bone cement mixing and its preparation process. Background Technology

[0002] In existing technologies, the materials used in traditional bone cement mixing often lack sufficient high-temperature abrasion resistance, which can cause severe wear and tear on the materials due to the heat generated during mixing. This wear not only affects the physical properties of the materials but may also lead to reduced mixing efficiency and increased surgical risks. Furthermore, the limited hydrophobicity of existing materials makes it easy for bone cement to adhere during mixing, increasing the complexity of cleaning and maintenance.

[0003] Meanwhile, the insufficient antibacterial properties of traditional materials increase the risk of postoperative infection, posing a threat to patient safety. These shortcomings urgently need to be addressed through the development and improvement of new materials to enhance the overall efficiency and safety of the bone cement mixing process.

[0004] Therefore, inventing a silicone rubber sheet for bone cement mixing and its preparation process is of great significance. Summary of the Invention

[0005] The purpose of this invention is to provide a silicone rubber sheet for bone cement mixing and its preparation process, so as to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A process for preparing silicone rubber sheets for bone cement mixing includes the following steps: S1: After preheating the kneader, adjust the roller gap, add silicone rubber, mix for 5-6 minutes, reduce the roller gap, add polytetrafluoroethylene, mix for 10-15 minutes, add fluorosilicone rubber and double vulcanizing agent in sequence, mix for 10-15 minutes, increase the roller gap, make tablets, let stand at room temperature, place the tablets on a flat vulcanizing machine for vulcanization, and obtain silicone rubber sheets;

[0008] In the preparation of silicone rubber sheet, the proportions of each component by mass are as follows: 90-100 parts silicone rubber, 5-10 parts polytetrafluoroethylene, 5-10 parts fluorosilicone rubber, and 1.6-2 parts divulcanizing agent.

[0009] The adjustable roller gap is 4-6mm, the narrowing roller gap is 2-3mm, and the widening roller gap is 3-4mm;

[0010] The preheating temperature is 30-35℃, the vulcanization temperature is 175-180℃, and the time is 10-12 minutes;

[0011] S2: Cut the silicone rubber sheet into shape, ultrasonically clean it in ethanol, and set aside;

[0012] The cutting specifications include: length 155-160mm, width 100-105mm, and thickness 3-4mm;

[0013] S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. After ultrasonic cleaning with ethanol, a rough silicone rubber sheet is obtained. The rough silicone rubber sheet is immersed in an 8-10 wt% polydiallyldimethylammonium chloride solution and ultrasonically treated. It is then removed and dried at 50-55℃ for 2-2.5 h. It is then immersed in an ethyl silicate solution and ultrasonically treated. It is left to stand in the solution at room temperature for 48-60 h and then vacuum dried. The surface of the rough silicone rubber sheet is cleaned except for the drilled area using a picosecond laser. Finally, it is immersed in a 20-25 wt% hexamethyldisilazane solution, heated to 35-45℃ for 2-3 h, and then vacuum dried to obtain a superhydrophobic silicone rubber sheet.

[0014] The nanosecond laser processing parameters include: wavelength 1064 nm, repetition rate 100 kHz, spot overlap 70%, scanning rate 1475 mm / s, spot diameter 50 μm, and laser energy density 12.5 J / cm². 2 The pulse width is 340 ns.

[0015] The picosecond laser drilling parameters include: wavelength 542nm, repetition rate 100kHz, spot overlap 75%, scanning rate 500mm / s, spot diameter 20μm, and laser energy density 14.3J / cm². 2 Pulse width 12ps;

[0016] The laser drilling process is a periodic array structure surface treatment, with parameters including: hole radius 100μm, hole spacing 100-258μm, and hole depth 400μm.

[0017] The ethyl silicate solution is composed of deionized water, anhydrous ethanol, ammonium hydroxide and ethyl silicate in a molar ratio of 0.5:1:1:3.5;

[0018] The surface cleaning parameters of the picosecond laser include: wavelength 542nm, repetition rate 100kHz, spot overlap 70%, scanning rate 590mm / s, spot diameter 20μm, and laser energy density 6.0J / cm². 2 Pulse width 12ps;

[0019] S4: Add 2-(dimethylamino)ethyl acrylate and 1-bromooctane to acetonitrile, stir well, and heat to 45-50℃ for 3 days to obtain ammonium bromide;

[0020] In the preparation of ammonium bromide, the molar ratio of 2-(dimethylamino)ethyl acrylate to 1-bromooctane is 1:1;

[0021] S5: Immerse the superhydrophobic silicone rubber sheet in a methanol solution containing 10-15 wt% 3-mercaptopropyltrimethoxysilane and 1% W / V potassium hydroxide, heat to 50-55℃ and react for 6-6.5 h, then immerse in methanol and sonicate, finally immerse in dichloromethane and stir for 3-3.5 h to obtain a mercapto-modified silicone rubber sheet; under a nitrogen atmosphere, ammonium bromide, 2-methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester, 2,2-dimethoxy-2- Phenylacetone was added to methanol and stirred until homogeneous. The mixture was then dropped onto the surface of a mercapto-modified silicone rubber plate and irradiated with ultraviolet light for 1-1.5 hours. The plate was then washed with methanol and deionized water and dried under vacuum to obtain an ammonium bromide-modified silicone rubber plate. The ammonium bromide-modified silicone rubber plate was then immersed in an 8-12 wt% L-proline solution and stirred at room temperature for 12-14 hours. Nitrogen gas was then introduced for 30-45 minutes, followed by nitric oxide until saturation. The plate was kept at this temperature for 1-1.5 hours to obtain a silicone rubber plate for bone cement mixing.

[0022] In the preparation of ammonium bromide modified silicone rubber sheet, the molar ratio of ammonium bromide to 2-methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester is 1:1;

[0023] The L-proline solution was adjusted to alkalinity using 0.01M sodium hydroxide.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] 1. This invention aims to improve the high-temperature friction resistance of silicone rubber sheets during bone cement mixing. Fluorosilicone rubber is used as a compatibilizer to improve the compatibility between silicone rubber and polytetrafluoroethylene (PTFE), significantly enhancing the high-temperature friction stability of the silicone rubber sheet while maintaining its original mechanical properties. The introduction of PTFE improves the high-temperature friction stability of the rubber and reduces its high-temperature coefficient of friction. During high-temperature friction and wear, a molten layer adheres to the rubber surface, reducing frictional resistance. It exhibits excellent wear resistance at high temperatures. The molten layer formed by friction prevents direct contact between air and the surface rubber, inhibiting high-temperature oxidation reactions on the rubber surface. This reduces frictional losses of the silicone rubber sheet caused by high temperatures during bone cement mixing, minimizing the impact on the performance of the bone cement during application.

[0026] 2. This invention aims to further enhance the abrasion resistance and antibacterial properties of the original silicone rubber sheet. After irradiating the silicone rubber surface with a nanosecond laser, a periodic circular hole array with a depth of 400 μm is created using a picosecond laser. Optimal hydrophobicity is achieved by adjusting the pore size and spacing of the periodic circular hole array, preventing bone cement from adhering to the silicone rubber sheet surface during mixing. Then, silica particles filled with ethyl silicate are directly hydrolyzed. After laser cleaning and silanization modification, a surface composed of soft silicone rubber and hard silica regions is formed, resulting in a superhydrophobic silicone rubber sheet with excellent abrasion resistance.

[0027] 3. Finally, this invention prepares a silicone rubber sheet with a quaternary ammonium ion liquid coating that exhibits antibacterial and antifouling properties due to the synergistic effect of interleukin and released nitric oxide by grafting ammonium bromide and 2-methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester onto the surface of a superhydrophobic silicone rubber sheet, and then introducing proline- through anion exchange between Br and proline to adsorb nitric oxide. Detailed Implementation

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] In the following examples, the silicone rubber specification was NE-5150, purchased from Dongjue Organosilicon (Nanjing) Co., Ltd.; the fluorosilicone rubber specification was FSR8460-U, purchased from Dongguan Ningdao Rubber Industry Co., Ltd.; the dichlorocuring agent specification was TC-14 divinyl chloride, purchased from Dongguan Tengqi Rubber & Plastic Technology Co., Ltd.; the polytetrafluoroethylene specification was MP1000, purchased from DuPont, USA; and the remaining raw materials were commercially available.

[0030] In the following examples, the preparation process of ammonium bromide includes the following steps: 10 mmol of 2-(dimethylamino)ethyl acrylate and 10 mmol of 1-bromooctane are added to 20 mL of acetonitrile, stirred evenly, and heated to 45 °C for 3 days to obtain ammonium bromide.

[0031] Example 1: A preparation process of silicone rubber sheet for bone cement mixing: including the following steps: S1: After preheating the kneader to 30°C for 5 minutes, adjust the roller gap to 4 mm, add 100 parts of silicone rubber, mix for 5 minutes, reduce the roller gap to 2 mm, add 5 parts of polytetrafluoroethylene, mix for 10 minutes, add 5 parts of fluorosilicone rubber and 1.6 parts of double vulcanizing agent in sequence, mix for 10 minutes, expand the roller gap to 3 mm, make tablets, let stand at room temperature, place the tablets on a flat vulcanizing machine at 175°C for 10 minutes to obtain silicone rubber sheet;

[0032] S2: Cut the silicone rubber sheet into shape, 157mm long, 102mm wide, and 3mm thick, and clean it ultrasonically in ethanol for later use.

[0033] S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. The sheet is then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet. The rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution and ultrasonically treated. It is then removed and dried at 50°C for 2 hours. Next, it is immersed in an ethyl silicate solution and ultrasonically treated. It is then left to stand at room temperature for 48 hours and vacuum dried. The surface of the rough silicone rubber sheet, except for the drilled areas, is cleaned using a picosecond laser. Finally, it is immersed in a 20wt% hexamethyldisilazane solution, heated to 35°C for 2 hours, and vacuum dried to obtain a superhydrophobic silicone rubber sheet. The laser drilling treatment is a periodic array structure surface treatment with parameters including: hole radius 100μm, hole spacing 258μm, and hole depth 400μm.

[0034] S4: A superhydrophobic silicone rubber sheet was immersed in a methanol solution containing 10 wt% 3-mercaptopropyltrimethoxysilane and 1% W / V potassium hydroxide, heated to 50°C for 6 h, then immersed in methanol and sonicated, and finally immersed in dichloromethane and stirred for 3 h to obtain a mercapto-modified silicone rubber sheet; under a nitrogen atmosphere, 0.3 mmol ammonium bromide and 0.3 mmol 2-Methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester and 24 mg of 2,2-dimethoxy-2-phenylacetophenone were added to methanol and stirred until homogeneous. The mixture was then dropped onto the surface of a mercapto-modified silicone rubber plate and irradiated with ultraviolet light for 1 hour. The plate was then washed with methanol and deionized water and dried under vacuum to obtain an ammonium bromide-modified silicone rubber plate. The ammonium bromide-modified silicone rubber plate was then immersed in an 8 wt% L-proline solution and stirred at room temperature for 12 hours. Nitrogen gas was then introduced for 30 minutes, followed by nitric oxide purging until saturation. The plate was then kept warm for 1 hour to obtain a silicone rubber plate for bone cement mixing.

[0035] Example 2: A process for preparing a silicone rubber sheet for bone cement mixing: including the following steps: S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. The sheet is then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet. The rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution, ultrasonically treated, removed and dried at 50°C for 2 hours, then immersed in an ethyl silicate solution, ultrasonically treated, left to stand at room temperature for 48 hours, vacuum dried, and the surface of the rough silicone rubber sheet except for the drilled area is cleaned using a picosecond laser. Finally, it is immersed in a 20wt% hexamethyldisilazane solution, heated to 35°C for 2 hours, and vacuum dried to obtain a superhydrophobic silicone rubber sheet. The laser drilling treatment is a periodic array structure surface treatment with parameters including: hole radius 100μm, hole spacing 154μm, and hole depth 400μm.

[0036] The remaining steps are the same as in Example 1.

[0037] Example 3: A process for preparing a silicone rubber sheet for bone cement mixing: including the following steps: S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. The sheet is then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet. The rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution, ultrasonically treated, removed and dried at 50°C for 2 hours, then immersed in an ethyl silicate solution, ultrasonically treated, left to stand at room temperature for 48 hours, vacuum dried, and the surface of the rough silicone rubber sheet except for the drilled area is cleaned using a picosecond laser. Finally, it is immersed in a 20wt% hexamethyldisilazane solution, heated to 35°C for 2 hours, and vacuum dried to obtain a superhydrophobic silicone rubber sheet. The laser drilling treatment is a periodic array structure surface treatment with parameters including: hole radius 100 μm, hole spacing 100 μm, and hole depth 400 μm.

[0038] The remaining steps are the same as in Example 1.

[0039] Comparative Example 1: A preparation process of a silicone rubber sheet for bone cement mixing: including the following steps: S1: After preheating the kneader to 30°C for 5 minutes, adjust the roller gap to 4 mm, add 100 parts of silicone rubber, mix for 5 minutes, reduce the roller gap to 2 mm, add 5 parts of fluorosilicone rubber and 1.6 parts of double vulcanizing agent in sequence, mix for 10 minutes, expand the roller gap to 3 mm, make tablets, let stand at room temperature, place the tablets on a flat vulcanizing machine at 175°C for 10 minutes to obtain silicone rubber sheet;

[0040] The remaining steps are the same as in Example 1.

[0041] Comparative Example 2: A preparation process of a silicone rubber sheet for bone cement mixing: including the following steps: S1: After preheating the kneader to 30°C for 5 minutes, adjust the roller gap to 4 mm, add 100 parts of silicone rubber, mix for 5 minutes, reduce the roller gap by 2 mm, add 5 parts of polytetrafluoroethylene, mix for 10 minutes, add 1.6 parts of double vulcanizing agent, mix for 10 minutes, increase the roller gap by 3 mm, make tablets, let stand at room temperature, place the tablets on a flat vulcanizing machine at 175°C for 10 minutes to obtain silicone rubber sheet;

[0042] The remaining steps are the same as in Example 1.

[0043] Comparative Example 3: A preparation process for a silicone rubber sheet for bone cement mixing: including the following steps: S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. The sheet is then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet. The rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution, ultrasonically treated, removed and dried at 50℃ for 2 hours, then immersed in an ethyl silicate solution, ultrasonically treated, left to stand at room temperature for 48 hours, vacuum dried, and the surface of the rough silicone rubber sheet except for the drilled area is cleaned using a picosecond laser. Finally, it is immersed in a 20wt% hexamethyldisilazane solution, heated to 35℃ for 2 hours, and vacuum dried to obtain a superhydrophobic silicone rubber sheet. The laser drilling treatment is a periodic array structure surface treatment with parameters including: hole radius 200μm, hole spacing 200μm, and hole depth 400μm.

[0044] The remaining steps are the same as in Example 1.

[0045] Comparative Example 4: A preparation process for a silicone rubber sheet for bone cement mixing: including the following steps: S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. The sheet is then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet. The rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution, ultrasonically treated, removed and dried at 50℃ for 2 hours, then immersed in an ethyl silicate solution, ultrasonically treated, left to stand at room temperature for 48 hours, vacuum dried, and the surface of the rough silicone rubber sheet except for the drilled area is cleaned using a picosecond laser. Finally, it is immersed in a 20wt% hexamethyldisilazane solution, heated to 35℃ for 2 hours, and vacuum dried to obtain a superhydrophobic silicone rubber sheet. The laser drilling treatment is a periodic array structure surface treatment with parameters including: hole radius 200μm, hole spacing 5150μm, and hole depth 400μm.

[0046] The remaining steps are the same as in Example 1.

[0047] Comparative Example 5: A preparation process for a silicone rubber sheet for bone cement mixing: including the following steps: S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser and then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet; the rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution, ultrasonically treated, removed and dried at 50℃ for 2h, then immersed in an ethyl silicate solution, ultrasonically treated, left to stand at room temperature for 48h, vacuum dried, the surface of the rough silicone rubber sheet except for the drilled area is cleaned with a picosecond laser, and finally immersed in a 20wt% hexamethyldisilazane solution, heated to 35℃ for 2h, and vacuum dried to obtain a superhydrophobic silicone rubber sheet;

[0048] The remaining steps are the same as in Example 1.

[0049] Comparative Example 6: A preparation process for a silicone rubber sheet for bone cement mixing: including the following steps: S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. The sheet is then ultrasonically cleaned with ethanol to obtain a rough silicone rubber sheet. The rough silicone rubber sheet is immersed in an 8wt% polydiallyldimethylammonium chloride solution, ultrasonically treated, removed and dried at 50℃ for 2 hours, then immersed in an ethyl silicate solution, ultrasonically treated, left to stand at room temperature for 48 hours, vacuum dried, and finally immersed in a 20wt% hexamethyldisilazane solution, heated to 35℃ for 2 hours, and vacuum dried to obtain a superhydrophobic silicone rubber sheet. The laser drilling treatment is a periodic array structure surface treatment with parameters including: hole radius 100μm, hole spacing 258μm, and hole depth 400μm.

[0050] The remaining steps are the same as in Example 1.

[0051] Experiment: High-Temperature Friction Resistance Test: A multifunctional material surface performance comprehensive tester was used to conduct a friction test at 100℃. The friction method was reciprocating friction, and the friction pair consisted of GCr15 steel balls with a diameter of 6mm. The friction test load was 5N, the motor speed was 300r / min, and relative motion occurred between the sample and the ball. The coefficient of friction measured after 60 minutes was the kinetic coefficient of friction. The contact angle of the silicone rubber sheet before and after friction was measured.

[0052] Antibacterial performance test: 25 μL of Escherichia coli and Staphylococcus aureus bacterial suspensions (2 × 10⁻⁶ μL, 2 × 10⁻⁶ μL) were tested. 4 CFUmL -1 The bacteria were dropped onto a commercially available silicone rubber plate and incubated at 37°C for 4 hours. Then, 2 mL of LB medium was added to dilute the bacteria, and 10 μL of the bacterial suspension was spread onto an LB agar plate. After incubation at 37°C for 18 hours, bacterial colonies were counted. The antibacterial performance after high-temperature friction was tested using the same method. A commercially available silicone rubber plate served as a negative control.

[0053] Antibacterial activity (%) = N阴性对照组 -N 硅橡胶板 / N 阴性对照组 ×100%.

[0054] The experimental data are shown in Table 1 below.

[0055] Table 1 Performance Test Data of Silicone Rubber Sheets

[0056] Conclusion: The silicone rubber sheet prepared by this invention has excellent high-temperature friction resistance and antibacterial properties.

[0057] The absence of polytetrafluoroethylene (PTFE) in Comparative Example 1 and the absence of fluorosilicone rubber in Comparative Example 2 resulted in reduced high-temperature friction resistance. This is because the rubber matrix softens and becomes more fluid under high-temperature conditions. The lack of PTFE dispersed in the rubber matrix reduces friction, resulting in a stable friction coefficient curve. Furthermore, the absence of fluorosilicone rubber ensures good compatibility and stable friction between the silicone rubber and PTFE at high temperatures.

[0058] In Comparative Example 3, increasing the hole radius led to a decrease in high-temperature friction resistance. This is because the surface area of ​​silica within the hole decreases, making it unable to provide crucial support during wear, reducing the direct force on the silicone rubber area, and decreasing the loss and deformation of silica within the hole.

[0059] In Comparative Example 4, increasing the pore spacing led to a decrease in high-temperature friction resistance. This is because the contact between the droplet and the surface exhibits a coexistence of Wenzel and Cassie properties. Liquids tend to spontaneously move from areas of high hydrophobicity to areas of low hydrophobicity. On surfaces with larger pore spacing, water droplets are more likely to contact the dehydrophobic silicone rubber regions, thus weakening the micro / nano hydrophobic structure.

[0060] In Comparative Example 5, only the surface underwent nanosecond laser treatment, resulting in a decrease in high-temperature friction resistance. This is because, before friction, the laser-processed surface initially exhibits a hierarchical micro / nano structure with dense, papillary nanoparticles, which primarily contribute to the surface's superhydrophobic properties. Under pressure and friction, the fragile nanoparticles on the surface are quickly worn away, and the sample surface roughness decreases slightly. As the surface continues to rub against the sandpaper, the papillary nanoparticles almost disappear, and some grooves plowed out by the sand grains can even be observed, leading to a rapid increase in the sample's surface roughness. Simultaneously, droplets on the sample surface will penetrate into these microscale grooves, and the contact state with the surface will change from the Cassie state to the Wenzel state, resulting in the loss of superhydrophobic properties.

[0061] In Comparative Example 6, the surface coating on the silicone rubber surface, excluding the pores, was not cleaned, resulting in reduced high-temperature friction resistance. Although the silica coating exhibited satisfactory superhydrophobicity, its excessive thickness and hardness made it prone to cracking and peeling on the soft silicone rubber substrate. Chemical changes in the silicone rubber areas or silica residues reduced its wear resistance.

[0062] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A process for preparing a silicone rubber sheet for bone cement mixing, characterized in that: Includes the following steps: S1: Add silicone rubber, fluorosilicone rubber, and double vulcanizing agent to a kneader, adjust the roller gap, form tablets, vulcanize, and obtain silicone rubber sheets; S2: Cut the silicone rubber sheet into shape, ultrasonically clean it in ethanol, and set aside; S3: The surface of the cleaned silicone rubber sheet is treated with a nanosecond laser and then with a picosecond laser for laser drilling. Then, nano-silica is prepared by hydrolysis and condensation of ethyl silicate to fill the holes. The surface except the drilled area is cleaned with a picosecond laser. Finally, the sheet is modified with hexamethyldisilazane for hydrophobicity to obtain a superhydrophobic silicone rubber sheet. S4: The surface of the superhydrophobic silicone rubber sheet is modified with mercapto groups. Ammonium bromide is grafted onto the surface through ultraviolet light mercaptoolefin reaction, followed by grafting through L-proline reaction. Finally, nitric oxide is absorbed to saturation to obtain a silicone rubber sheet for bone cement mixing.

2. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 1, characterized in that: Includes the following steps: S1: After preheating the kneader, adjust the roller gap, add silicone rubber, mix for 5-6 minutes, reduce the roller gap, add polytetrafluoroethylene, mix for 10-15 minutes, add fluorosilicone rubber and double vulcanizing agent in sequence, mix for 10-15 minutes, expand the roller gap, make tablets, let stand at room temperature, place the tablets on a flat vulcanizing machine for vulcanization, and obtain silicone rubber raw sheets. S2: Cut the silicone rubber sheet into shape, ultrasonically clean it in ethanol, and set aside; S3: After cleaning, the surface of the silicone rubber sheet is treated with a nanosecond laser, and then laser drilling is performed on the surface using a picosecond laser. After ultrasonic cleaning with ethanol, a rough silicone rubber sheet is obtained. The rough silicone rubber sheet is immersed in an 8-10 wt% polydiallyldimethylammonium chloride solution and ultrasonically treated. It is then removed and dried at 50-55℃ for 2-2.5 h. It is then immersed in an ethyl silicate solution and ultrasonically treated. It is left to stand in the solution at room temperature for 48-60 h and then vacuum dried. The surface of the rough silicone rubber sheet is cleaned except for the drilled area using a picosecond laser. Finally, it is immersed in a 20-25 wt% hexamethyldisilazane solution, heated to 35-45℃ for 2-3 h, and then vacuum dried to obtain a superhydrophobic silicone rubber sheet. S4: Immerse a superhydrophobic silicone rubber sheet in a methanol solution containing 10-15 wt% 3-mercaptopropyltrimethoxysilane and 1% W / V potassium hydroxide, heat to 50-55℃ and react for 6-6.5 h, then immerse in methanol and sonicate, finally immerse in dichloromethane and stir for 3-3.5 h to obtain a mercapto-modified silicone rubber sheet; under a nitrogen atmosphere, ammonium bromide, 2-methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester, 2,2-dimethoxy-2- Phenylacetone was added to methanol and stirred until homogeneous. The mixture was then dropped onto the surface of a mercapto-modified silicone rubber plate and irradiated with ultraviolet light for 1-1.5 hours. The plate was then washed with methanol and deionized water and dried under vacuum to obtain an ammonium bromide-modified silicone rubber plate. The ammonium bromide-modified silicone rubber plate was then immersed in an 8-12 wt% L-proline solution and stirred at room temperature for 12-14 hours. Nitrogen gas was then introduced for 30-45 minutes, followed by nitric oxide until saturation. The plate was kept at this temperature for 1-1.5 hours to obtain a silicone rubber plate for bone cement mixing.

3. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 2, characterized in that: In the preparation of silicone rubber sheet, the proportions of each component by mass are as follows: 90-100 parts silicone rubber, 5-10 parts polytetrafluoroethylene, 5-10 parts fluorosilicone rubber, and 1.6-2 parts dicurvature agent.

4. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 2, characterized in that: The adjustable roller gap is 4-6mm, the narrowing roller gap is 2-3mm, and the widening roller gap is 3-4mm.

5. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 2, characterized in that: The laser drilling process is a periodic array structure surface treatment, with parameters including: hole radius of 100μm, hole spacing of 100-258μm, and hole depth of 400μm.

6. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 2, characterized in that: The ethyl silicate solution is composed of deionized water, anhydrous ethanol, ammonium hydroxide and ethyl silicate in a molar ratio of 0.5:1:1:3.

5.

7. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 2, characterized in that: The preparation method of ammonium bromide includes the following steps: adding 2-(dimethylamino)ethyl acrylate and 1-bromooctane to acetonitrile, stirring evenly, and heating to 45-50℃ for 3 days to obtain ammonium bromide.

8. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 7, characterized in that: In the preparation of ammonium bromide, the molar ratio of 2-(dimethylamino)ethyl acrylate to 1-bromooctane is 1:

1.

9. The preparation process of a silicone rubber sheet for bone cement mixing according to claim 2, characterized in that: In the preparation of ammonium bromide modified silicone rubber sheet, the molar ratio of ammonium bromide to 2-methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester is 1:

1.

10. A silicone rubber sheet for bone cement mixing prepared by a process according to any one of claims 1-9.

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