Medical catheter material and production process thereof

Abstract

The invention belongs to the technical field of high-molecular compounds, and particularly relates to a medical catheter material and a production process thereof. The process comprises the following steps: preparing nano-silver / medical thermoplastic polyurethane (TPU) master batch, preparing barium sulfate / TPU developing master batch, co-extruding three layers of catheters, coating a hydrophilic lubricating coating, and coating for the second time. According to the production process, continuous production can be achieved, the production efficiency is improved, and the product performance is remarkably improved. The process is not only a technical innovation, but also a systematic solution, and the balance of performance, cost and efficiency is realized through ingenious process integration and material design from clinical requirements.

Description

Technical Field

[0001] This invention belongs to the field of polymer compound technology, specifically relating to a medical catheter material and its manufacturing process. Background Technology

[0002] Initially, natural silicone was used as the material for medical catheters, and the process has been continuously optimized. However, natural rubber suffers from severe scaling, leading to the increasing use of new materials such as silicone rubber, polytetrafluoroethylene (PTFE), and polyethylene. Different catheter materials have different advantages and disadvantages. Silicone rubber has become one of the commonly used medical catheter materials due to its excellent high and low temperature resistance, radiation resistance, low allergenicity, and good biocompatibility. However, silicone rubber is prone to causing thrombosis, posing certain clinical risks. PTFE has an extremely low coefficient of friction and is hydrophobic, ensuring it is not easily wetted by body fluids and reducing the possibility of water absorption within the body.

[0003] Polyvinyl chloride (PVC) contains plasticizers and additives, posing certain safety risks and raising public concerns. Polyurethane, on the other hand, possesses good mechanical flexibility, high tear strength, and good biocompatibility, allowing for structural customization to meet various mechanical requirements. However, existing materials still suffer from drawbacks: poor catheter strength and dimensional stability, insufficient biocompatibility and functional integration, difficulty in meeting comprehensive requirements for delivery, bending resistance, and blood compatibility, and multi-lumen catheters are prone to fluid interference. Summary of the Invention

[0004] To address the deficiencies in the prior art, this invention provides a manufacturing process for medical catheter materials that exhibit strong bending resistance and a certain degree of antibacterial properties.

[0005] A manufacturing process for a medical catheter material includes the following steps:

[0006] Step (a) Preparation of nano-silver / medical-grade thermoplastic polyurethane (TPU) masterbatch: Vacuum dry medical-grade thermoplastic polyurethane at 80°C for 4-5 hours, mix nano-silver and medical-grade thermoplastic polyurethane powder in a high-speed mixer for 5-8 minutes to prepare a 20% nano-silver concentrated masterbatch, and then mix the concentrated masterbatch with pure medical-grade thermoplastic polyurethane to prepare a 3% nano-silver functional masterbatch;

[0007] Step (b) Preparation of barium sulfate / TPU developing masterbatch: Barium sulfate is treated with 2wt% silane coupling agent KH-550 to increase its affinity with TPU. Then, a 10~20nm silica thin layer is coated on the surface of barium sulfate. The treated barium sulfate and TPU are blended in a twin-screw extruder and finally pelletized underwater to prevent thermal oxidation degradation.

[0008] Step (c) Three-layer co-extrusion: Preheat the three-layer co-extrusion extruder for 1.5 hours. After reaching the set temperature, keep it warm for 30 minutes. Inner extruder (Φ30mm): Load nano silver / TPU masterbatch and chlorhexidine. Middle extruder (Φ45mm): Load barium sulfate / TPU developing masterbatch + pure TPU (1:1 mixture). Outer extruder (Φ25mm): Load TPU + PEG (1:1 mixture). Continuous extrusion.

[0009] Step (d) Hydrophilic lubricating coating: Weigh PVP and PEG in a 1:1 ratio, mix them evenly, add ethanol, stir and dissolve in a 40°C water bath. After it is completely dissolved, slowly add deionized water and continue stirring for 1 hour to obtain a transparent solution. Filter the solution through a 0.45μm filter membrane to remove impurities and obtain a coating liquid. Then spray the coating liquid onto the surface of the conduit obtained in step (c), and dry it at 55°C, 60°C, and 65°C for 20, 30, and 40 seconds, respectively.

[0010] Step (e) Secondary coating: The catheter obtained in step (d) is coated with an anticoagulant and dried at 40°C for 30 seconds to obtain medical catheter material;

[0011] By weight, it includes the following materials: 88-92 parts of medical-grade thermoplastic polyurethane, 0.12 parts of nano silver (particle size 20-40nm), 0.40-1 part of chlorhexidine, 1-3 parts of anticoagulant, 3-4 parts of barium sulfate nanoparticles, 1 part of PEG, and 1 part of PVP.

[0012] Preferably, the process parameters of the twin-screw extruder in step (b) are: temperature range of 175~185℃, screw speed of 150~200rpm, and vacuum degassing maintained at -0.08MPa.

[0013] Preferably, in step (c), the temperature of each extruder in the three-layer co-extrusion extruder is set as follows: inner layer: 180 / 185 / 190 / 190 / 185℃ (from the feed port to the die), middle layer: 185 / 190 / 195 / 195 / 190℃, outer layer: 190 / 195 / 200 / 200 / 195℃, and die: 195℃ (each section is independently temperature controlled).

[0014] Preferably, in step (c), the thickness of each layer is inner layer: middle layer: outer layer = 20%: 50%: 30%.

[0015] Preferably, the spraying conditions in step (e) are: a spraying distance of 150 nm and a coating amount of 0.5~1.0 mg / cm2.

[0016] Preferably, the anticoagulant in step (e) is a heparin-mimicking polymer.

[0017] More preferably, the preparation method of the heparin-mimicking polymer is as follows: polyurethane is dissolved in dichloromethane, concentrated sulfuric acid is slowly added dropwise under an ice bath, and the temperature is controlled at <10℃. After the addition is complete, the temperature is raised to 25℃ and the reaction is carried out for 24 hours. After the reaction is complete, the reaction solution is slowly poured into ice water to precipitate and filter. The solid is washed with cold water until neutral, then neutralized with sodium carbonate solution, washed, and vacuum dried to obtain sulfonated polyurethane. 8g of sulfonated polyurethane is taken, 92g of deionized water is added, and 1g of Irgacure 2959 (first dissolved in a small amount of ethanol) is added. The mixture is processed by a high-pressure homogenizer to obtain a dispersion with an 8% solid content and a pH of about 6.5~7.5.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0019] This invention proposes a multi-layered antibacterial and antithrombotic catheter with a synergistic antibacterial mechanism: combining rapid antibacterial action of nano-silver with long-term inhibition of chlorhexidine to reduce the risk of bacterial resistance. Furthermore, compared to imported high-end antibacterial catheters, the cost is reduced; compared to ordinary domestic catheters, the infection rate and thrombosis rate are significantly reduced.

[0020] The production process described in this invention is flexible and allows for continuous production, improving efficiency and ensuring consistency. It significantly enhances product performance while ensuring technical feasibility and economic viability. This process is not only a technological innovation but also a systematic solution. Starting from clinical needs, it achieves a balance between performance, cost, and efficiency through ingenious process integration and material design. Detailed Implementation

[0021] The embodiments of the technical solution of the present invention will be described in detail below with reference to the examples. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and are therefore only examples, and should not be used to limit the scope of protection of the present invention.

[0022] It should be noted that, unless otherwise specified, the experimental methods used in the implementation examples are all conventional methods; and the materials and reagents used are all commercially available unless otherwise specified.

[0023] In this invention, unless otherwise stated, all “parts” and percentages (%) refer to weight percentages.

[0024] In this invention, unless otherwise stated, the sum of all percentages in all compositions is 100%.

[0025] In this invention, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0~5" means that all real numbers between "0~5" have been listed in this document, and "0~5" is simply a shortened representation of these numerical combinations.

[0026] In this invention, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0027] In this invention, unless otherwise specified, all steps mentioned herein may be performed sequentially or randomly, but are preferably performed sequentially; for example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially; for example, the method may also include step (c), indicating that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0028] In this invention, unless otherwise specified, the specific values ​​and substances in the embodiments of this invention can be combined with other features in the description of this invention; for example, if the specification mentions that the reaction temperature is 10~100℃, while the embodiment mentions that the reaction temperature is 20℃, then it can be considered that this invention has specifically disclosed the range of 10~20℃ or the range of 20~100℃, and this range can be combined with other features in the description to form a new technical solution.

[0029] Example 1

[0030] Step (a) Preparation of nano-silver / medical-grade thermoplastic polyurethane (TPU) masterbatch: 2 kg of medical-grade thermoplastic polyurethane was vacuum dried at 80°C for 4 hours. 40 g of nano-silver and medical-grade thermoplastic polyurethane powder were mixed in a high-speed mixer for 8 minutes to prepare a 20% nano-silver concentrated masterbatch. Then, the concentrated masterbatch was mixed with pure medical-grade thermoplastic polyurethane to prepare a 3% nano-silver functional masterbatch.

[0031] Step (b) Preparation of barium sulfate / TPU developing masterbatch: 150g of barium sulfate was treated with 200mL of 2wt% silane coupling agent KH-550 to increase its affinity with TPU. Then, a 10~20nm silica thin layer was coated on the surface of the barium sulfate. 100g of the treated barium sulfate and 566g of TPU were blended in a twin-screw extruder at a temperature range of 175~185℃, a screw speed of 150~200rpm, and vacuum degassing maintained at -0.08Mpa. Finally, the mixture was pelletized underwater to prevent thermal oxidation degradation.

[0032] Step (c) Three-layer co-extrusion: Preheat the three-layer co-extrusion extruder for 1.5 hours. Set the temperatures of each extruder as follows: Inner layer: 180 / 185 / 190 / 190 / 185℃ (from feed port to die), Middle layer: 185 / 190 / 195 / 195 / 190℃, Outer layer: 190 / 195 / 200 / 200 / 195℃, Die: 195℃ (independent temperature control for each section). After reaching the set temperature, maintain the temperature for 30 minutes. Inner layer extruder (Φ30mm): Load nano silver / TPU masterbatch, Middle layer extruder (Φ45mm): Load barium sulfate / TPU developing masterbatch + pure TPU (1:1 mixture), Outer layer extruder (Φ25mm): Load TPU + PEG (1:1 mixture), and extrude continuously.

[0033] Step (d) Hydrophilic lubricating coating: Weigh PVP and PEG in a 1:1 ratio, mix them evenly, add ethanol, stir and dissolve in a 40°C water bath. After it is completely dissolved, slowly add deionized water and continue stirring for 1 hour to obtain a transparent solution. Filter the solution through a 0.45μm filter membrane to remove impurities and obtain a coating liquid. Then spray the coating liquid onto the surface of the conduit obtained in step (c), and dry it at 55°C, 60°C, and 65°C for 20, 30, and 40 seconds, respectively.

[0034] Step (e) Secondary Coating: Dissolve polyurethane in dichloromethane, and slowly add concentrated sulfuric acid dropwise under an ice bath, controlling the temperature <10℃. After the addition is complete, raise the temperature to 25℃ and react for 24 hours. After the reaction is complete, slowly pour the reaction solution into ice water to precipitate and filter. Wash the solid with cold water until neutral, then neutralize with sodium carbonate solution, wash, and vacuum dry to obtain sulfonated polyurethane. Take 8g of sulfonated polyurethane, add 92g of deionized water, add 1g of Irgacure 2959 (first dissolved in a small amount of ethanol), and process with a high-pressure homogenizer to obtain an 8% solid content dispersion with a pH of approximately 6.5~7.5. Spray the catheter obtained in step (d) with 3 parts of heparin-simulated polymer at a distance of 150nm, with a coating amount of 0.5~1.0mg / cm. 2 The coating is applied and dried at 40°C for 30 seconds to obtain medical catheter material 1.

[0035] Example 2

[0036] Step (a) Preparation of nano-silver / medical-grade thermoplastic polyurethane (TPU) masterbatch: 2 kg of medical-grade thermoplastic polyurethane was vacuum dried at 80°C for 4 hours. 40 g of nano-silver and medical-grade thermoplastic polyurethane powder were mixed in a high-speed mixer for 7 minutes to prepare a 20% nano-silver concentrated masterbatch. Then, the concentrated masterbatch was mixed with pure medical-grade thermoplastic polyurethane to prepare a 3% nano-silver functional masterbatch.

[0037] Step (b) Preparation of barium sulfate / TPU developing masterbatch: 150g of barium sulfate was treated with 200mL of 2wt% silane coupling agent KH-550 to increase its affinity with TPU. Then, a 10~20nm silica thin layer was coated on the surface of the barium sulfate. 100g of the treated barium sulfate and 566g of TPU were blended in a twin-screw extruder at a temperature range of 175~185℃, a screw speed of 150~200rpm, and vacuum degassing maintained at -0.08Mpa. Finally, the mixture was pelletized underwater to prevent thermal oxidation degradation.

[0038] Step (c) Three-layer co-extrusion: Preheat the three-layer co-extrusion extruder for 1.5 hours. Set the temperatures of each extruder as follows: Inner layer: 180 / 185 / 190 / 190 / 185℃ (from feed port to die), Middle layer: 185 / 190 / 195 / 195 / 190℃, Outer layer: 190 / 195 / 200 / 200 / 195℃, Die: 195℃ (independent temperature control for each section). After reaching the set temperature, maintain the temperature for 30 minutes. Inner layer extruder (Φ30mm): Load nano silver / TPU masterbatch, Middle layer extruder (Φ45mm): Load barium sulfate / TPU developing masterbatch + pure TPU (1:1 mixture), Outer layer extruder (Φ25mm): Load TPU + PEG (1:1 mixture), and extrude continuously.

[0039] Step (d) Hydrophilic lubricating coating: Weigh PVP and PEG in a 1:1 ratio, mix them evenly, add ethanol, stir and dissolve in a 40°C water bath. After it is completely dissolved, slowly add deionized water and continue stirring for 1 hour to obtain a transparent solution. Filter the solution through a 0.45μm filter membrane to remove impurities and obtain a coating liquid. Then spray the coating liquid onto the surface of the conduit obtained in step (c), and dry it at 55°C, 60°C, and 65°C for 20, 30, and 40 seconds, respectively.

[0040] Step (e) Secondary Coating: Dissolve polyurethane in dichloromethane, and slowly add concentrated sulfuric acid dropwise under an ice bath, controlling the temperature <10℃. After the addition is complete, raise the temperature to 25℃ and react for 24 hours. After the reaction is complete, slowly pour the reaction solution into ice water to precipitate and filter. Wash the solid with cold water until neutral, then neutralize with sodium carbonate solution, wash, and vacuum dry to obtain sulfonated polyurethane. Take 8g of sulfonated polyurethane, add 92g of deionized water, add 1g of Irgacure 2959 (first dissolved in a small amount of ethanol), and process with a high-pressure homogenizer to obtain an 8% solid content dispersion with a pH of approximately 6.5~7.5. Spray the catheter obtained in step (d) with 1 part heparin-simulated polymer at a distance of 150nm, with a coating amount of 0.5~1.0mg / cm. 2 The coating is applied and dried at 40°C for 30 seconds to obtain medical catheter material 2.

[0041] Example 3

[0042] Step (a) Preparation of nano-silver / medical-grade thermoplastic polyurethane (TPU) masterbatch: 2 kg of medical-grade thermoplastic polyurethane was vacuum dried at 80°C for 5 hours. 40 g of nano-silver and medical-grade thermoplastic polyurethane powder were mixed in a high-speed mixer for 5 minutes to prepare a 20% nano-silver concentrated masterbatch. Then, the concentrated masterbatch was mixed with pure medical-grade thermoplastic polyurethane to prepare a 3% nano-silver functional masterbatch.

[0043] Step (b) Preparation of barium sulfate / TPU developing masterbatch: 150g of barium sulfate was treated with 200mL of 2wt% silane coupling agent KH-550 to increase its affinity with TPU. Then, a 10~20nm silica thin layer was coated on the surface of the barium sulfate. 100g of the treated barium sulfate and 566g of TPU were blended in a twin-screw extruder at a temperature range of 175~185℃, a screw speed of 150~200rpm, and vacuum degassing maintained at -0.08Mpa. Finally, the mixture was pelletized underwater to prevent thermal oxidation degradation.

[0044] Step (c) Three-layer co-extrusion: Preheat the three-layer co-extrusion extruder for 1.5 hours. Set the temperatures of each extruder as follows: Inner layer: 180 / 185 / 190 / 190 / 185℃ (from feed port to die), Middle layer: 185 / 190 / 195 / 195 / 190℃, Outer layer: 190 / 195 / 200 / 200 / 195℃, Die: 195℃ (independent temperature control for each section). After reaching the set temperature, maintain the temperature for 30 minutes. Inner layer extruder (Φ30mm): Load nano silver / TPU masterbatch, Middle layer extruder (Φ45mm): Load barium sulfate / TPU developing masterbatch + pure TPU (1:1 mixture), Outer layer extruder (Φ25mm): Load TPU + PEG (1:1 mixture), and extrude continuously.

[0045] Step (d) Hydrophilic lubricating coating: Weigh PVP and PEG in a 1:1 ratio, mix them evenly, add ethanol, stir and dissolve in a 40°C water bath. After it is completely dissolved, slowly add deionized water and continue stirring for 1 hour to obtain a transparent solution. Filter the solution through a 0.45μm filter membrane to remove impurities and obtain a coating liquid. Then spray the coating liquid onto the surface of the conduit obtained in step (c), and dry it at 55°C, 60°C, and 65°C for 20, 30, and 40 seconds, respectively.

[0046] Step (e) Secondary Coating: Dissolve polyurethane in dichloromethane, and slowly add concentrated sulfuric acid dropwise under an ice bath, controlling the temperature <10℃. After the addition is complete, raise the temperature to 25℃ and react for 24 hours. After the reaction is complete, slowly pour the reaction solution into ice water to precipitate and filter. Wash the solid with cold water until neutral, then neutralize with sodium carbonate solution, wash, and vacuum dry to obtain sulfonated polyurethane. Take 8g of sulfonated polyurethane, add 92g of deionized water, add 1g of Irgacure 2959 (first dissolved in a small amount of ethanol), and process with a high-pressure homogenizer to obtain an 8% solid content dispersion with a pH of approximately 6.5~7.5. Spray the conduit obtained in step (d) with 1~3 parts of heparin-simulated polymer at a distance of 150nm, with a coating amount of 0.5~1.0mg / cm. 2 The coating is then dried at 40°C for 30 seconds to obtain medical catheter material 3.

[0047] Performance testing

[0048] The medical catheter materials prepared in Examples 1-3 were subjected to impact resistance and tensile properties tests. The experimental results are shown in Table 1.

[0049] Table 1

[0050]

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A manufacturing process for a medical catheter material, characterized in that, Includes the following steps: Step (a) Preparation of nano-silver / medical-grade thermoplastic polyurethane (TPU) masterbatch: Vacuum dry medical-grade thermoplastic polyurethane at 80°C for 4-5 hours, mix nano-silver and medical-grade thermoplastic polyurethane powder in a high-speed mixer for 5-8 minutes to prepare a 20% nano-silver concentrated masterbatch, and then mix the concentrated masterbatch with pure medical-grade thermoplastic polyurethane to prepare a 3% nano-silver functional masterbatch; Step (b) Preparation of barium sulfate / TPU developing masterbatch: Barium sulfate is treated with 2wt% silane coupling agent KH-550 to increase its affinity with TPU. Then, a 10~20nm silica thin layer is coated on the surface of barium sulfate. The treated barium sulfate and TPU are blended in a twin-screw extruder and finally pelletized underwater to prevent thermal oxidation degradation. Step (c) Three-layer co-extrusion: Preheat the three-layer co-extrusion extruder for 1.5 hours. After reaching the set temperature, keep it warm for 30 minutes. Inner extruder (Φ30mm): Load nano silver / TPU masterbatch and chlorhexidine. Middle extruder (Φ45mm): Load barium sulfate / TPU developing masterbatch + pure TPU (1:1 mixture). Outer extruder (Φ25mm): Load TPU + PEG (1:1 mixture). Continuous extrusion. Step (d) Hydrophilic lubricating coating: Weigh PVP and PEG in a 1:1 ratio, mix them evenly, add ethanol, stir and dissolve in a 40°C water bath. After it is completely dissolved, slowly add deionized water and continue stirring for 1 hour to obtain a transparent solution. Filter the solution through a 0.45μm filter membrane to remove impurities and obtain a coating liquid. Then spray the coating liquid onto the surface of the conduit obtained in step (c), and dry it at 55°C, 60°C, and 65°C for 20, 30, and 40 seconds, respectively. Step (e) Secondary coating: The catheter obtained in step (d) is coated with an anticoagulant and dried at 40°C for 30 seconds to obtain medical catheter material; By weight, it includes the following materials: 88-92 parts of medical-grade thermoplastic polyurethane, 0.12 parts of nano silver (particle size 20-40nm), 0.40-1 part of chlorhexidine, 1-3 parts of anticoagulant, 3-4 parts of barium sulfate nanoparticles, 1 part of PEG, and 1 part of PVP.

2. The manufacturing process of a medical catheter material according to claim 1, characterized in that, The process parameters of the twin screw extruder in step (b) are: temperature range of 175~185℃, screw speed of 150~200rpm, and vacuum degassing maintained at -0.08MPa.

3. The manufacturing process of a medical catheter material according to claim 1, characterized in that, In step (c), the temperature of each extruder in the three-layer co-extrusion extruder is set as follows: inner layer: 180 / 185 / 190 / 190 / 185℃ (from the feed port to the die head), middle layer: 185 / 190 / 195 / 195 / 190℃, outer layer: 190 / 195 / 200 / 200 / 195℃, and die head: 195℃ (each section is independently temperature controlled).

4. The manufacturing process of a medical catheter material according to claim 1, characterized in that, In step (c), the thickness of each layer is inner layer: middle layer: outer layer = 20%: 50%: 30%.

5. The manufacturing process of a medical catheter material according to claim 1, characterized in that, The spraying conditions in step (e) are: spraying distance of 150 nm and coating amount of 0.5~1.0 mg / cm³. 2 .

6. The manufacturing process of a medical catheter material according to claim 1, characterized in that, In step (e), the anticoagulant is a heparin-mimicking polymer.

7. The manufacturing process of a medical catheter material according to claim 6, characterized in that, The preparation method of the heparin-mimicking polymer is as follows: Polyurethane is dissolved in dichloromethane, concentrated sulfuric acid is slowly added dropwise under ice bath, and the temperature is controlled at <10℃. After the addition is complete, the temperature is raised to 25℃ and the reaction is carried out for 24 hours. After the reaction is complete, the reaction solution is slowly poured into ice water to precipitate and filter. The solid is washed with cold water until neutral, then neutralized with sodium carbonate solution, washed, and vacuum dried to obtain sulfonated polyurethane. Take 8g of sulfonated polyurethane, add 92g of deionized water, add 1g of Irgacure 2959 (first dissolved in a small amount of ethanol), and process with a high-pressure homogenizer to obtain a dispersion with an 8% solid content and a pH of about 6.5~7.5.

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