Medical tube and preparation method thereof

Abstract

The invention discloses a medical tube and a preparation method thereof. The medical tube comprises a polyolefin elastomer which is a copolymer elastomer formed by olefin and high-carbon alpha-olefin, and the mass percentage of the high-carbon alpha-olefin is larger than or equal to 20%. The preparation method of the medical tube comprises the following steps: adding the polyolefin elastomer into an extruder (adding an auxiliary agent at the same time), and preparing the medical tube through an extrusion molding process. The medical tube has the advantages of solvent resistance, acid and alkali resistance, high elasticity, long service life and the like, and balances the plastic advantages of solvent resistance, acid and alkali resistance and the like and the rubber advantages of high elasticity, long service life and the like.

Description

Technical Field

[0001] This invention belongs to the technical field of medical devices, specifically relating to medical tubes and their preparation methods. Background Technology

[0002] The polyolefin elastomer (POE) market is large, with rapid demand growth and a significant market gap, making it a promising candidate for high-end materials. The presence of α-olefins disrupts the regular arrangement of polyethylene segments in the POE molecular structure, resulting in a soft, coiled structure. However, because the comonomer content of α-olefins is 20-30%, some crystallizable polyethylene segments are also retained. This results in a POE molecular structure containing both amorphous regions formed by the polymerization of ethylene and α-olefins, and crystalline polyethylene segments. This unique structure gives POE both the excellent thermoplasticity of plastics and the high elasticity of rubber. Furthermore, the absence of unsaturated double bonds in the POE molecular structure gives it excellent weather resistance and chemical corrosion resistance; its narrow molecular weight distribution provides high impact resistance and good flowability; and its non-polar molecular structure makes it difficult to form hydrogen bonds with water molecules, thus providing excellent water vapor barrier properties. Therefore, POE exhibits excellent physical and mechanical properties (high elasticity, high elongation, high strength), good low-temperature performance, excellent aging resistance, and UV resistance. PoE, possessing the dual advantages of both plastics and rubber, is widely used in photovoltaic films, automotive parts, footwear materials, packaging, and home appliances, among other fields. High-end PoE is also used in premium pipe materials, high-grade packaging films, lithium battery separators, wire and cable materials, and medical materials.

[0003] Despite strong market demand for POE, the production barriers for POE products are relatively high.

[0004] Research on the application of high-end POE in high-grade tubing materials, especially medical tubing materials (such as medical tubing), is still limited. Currently, medical tubing on the market is mainly made of silicone. The requirements for medical tubing products are to maintain the longest possible lifespan while meeting the specific operating conditions of customers. Specifically, this requires balancing the advantages of POE, such as solvent resistance and acid / alkali resistance, with the advantages of rubber, such as high elasticity and long lifespan. Summary of the Invention

[0005] The present invention aims to solve the technical problems existing in the prior art. To this end, the present invention proposes a medical tube that has both solvent resistance and acid and alkali resistance, as well as the advantages of silicone rubber such as high elasticity and long service life.

[0006] The present invention also proposes a method for preparing the above-mentioned medical tube.

[0007] According to one aspect of the invention, a medical tube is provided, the medical tube comprising a polyolefin elastomer (POE), said polyolefin elastomer being a copolymer elastomer formed from an olefin and a high carbon α-olefin, said high carbon α-olefin having a mass percentage ≥20%.

[0008] Specifically, polyolefin elastomers have high melting points, low Tg, and high crystallization temperatures (50~60℃), and possess excellent processing performance and flexibility.

[0009] In some embodiments of the present invention, the olefin is selected from at least one of ethylene, propylene, and ethylene-propylene copolymer.

[0010] In some embodiments of the present invention, the high-carbon α-olefin is an α-olefin containing ≥4 carbon atoms.

[0011] In some embodiments of the present invention, the high-carbon α-olefin is an α-olefin with ≥4 carbon atoms and ≤10 carbon atoms.

[0012] In some embodiments of the present invention, the high carbon α-olefin is selected from at least one of 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene.

[0013] In some embodiments of the present invention, the mass percentage of the high carbon α-olefin is ≥20%; preferably, the mass percentage of the high carbon α-olefin is 20%~30%; more preferably, the mass percentage of the high carbon α-olefin is 22.5%~27.5%.

[0014] In some preferred embodiments of the present invention, the high-carbon α-olefin is selected from 1-octene, and the mass percentage of 1-octene is ≥20%. Preferably, the mass percentage of 1-octene is 20%~30%; more preferably, the mass percentage of 1-octene is 22.5%~27.5%.

[0015] In some embodiments of the present invention, the medical tube further includes an adjuvant selected from at least one of anti-aging agents and anti-radiation agents.

[0016] Specifically, the selection of the adjuvants should meet the specific processing and subsequent medical tube usage conditions, and is not limited to the selections mentioned above.

[0017] According to another aspect of the present invention, a method for preparing the medical tube is provided, comprising the following steps: The medical tube is prepared by adding polyolefin elastomer to an extruder and then extruding it.

[0018] In some embodiments of the present invention, the polyolefin elastomer and additives are mixed and added to the extruder, and the medical tube is prepared by the extrusion molding process.

[0019] In some embodiments of the present invention, the extruder includes a feeding section, an extrusion section, and a plasticizing section connected in sequence.

[0020] Specifically, the feeding section is used to transport the added raw materials to the extrusion section.

[0021] The extrusion section includes a screw, the volume of which gradually decreases to adapt to changes in the material's physical state. The extrusion section is used to compact and melt the material, establishing pressure.

[0022] Specifically, the melting temperature of the extrusion section is 100~195℃.

[0023] The plasticizing section includes a screw with a shallow screw groove. The function of the plasticizing section is to extrude the molten material from the extrusion section at a fixed quantity and temperature to the very front end of the screw.

[0024] In some embodiments of the present invention, the extrusion molding process also uses an extruder head, a fixing device, and a cooling device.

[0025] Specifically, the extruder head is connected to the end of the plasticizing section away from the extrusion section; the extruder head includes a die, a mandrel, and a flow divider, the mandrel and the flow divider are disposed inside the die, and the flow divider is disposed at the port of the die connected to the end of the plasticizing section away from the extrusion section.

[0026] Specifically, the die is provided with a fixing device at the end away from the plasticizing section, which can meet different size requirements. The fixing device is set by a special device (for easy fixing and replacement).

[0027] Specifically, the function of the extruder head is to change the molten material from spiral motion to linear motion; to generate the necessary molding pressure to ensure the product is dense; and to further plasticize the material through the extruder head.

[0028] The die is used to shape the outer surface of the plastic part, and the mandrel is used to shape the inner surface of the plastic part; the diverter shuttle is used to divert the molten material from the extruder to form a tubular product preform, and further heat and plasticize it.

[0029] Specifically, the fixing device is used to stabilize the cross-sectional shape of the high-temperature plastic part extruded from the die of the extruder head and to make necessary corrections; the cooling device is used to cool and shape the part, thereby forming a medical tube.

[0030] Specifically, this invention involves adding materials such as polyolefin elastomers into the feed barrel of an extruder. Under the action of the rotating extruder screw, the material is conveyed forward along the screw groove. During this process, it continuously receives external heating and frictional heat, gradually melting into a viscous flow state. Then, under the action of the extrusion section, the molten material passes through an extruder head die with a specific shape and other auxiliary devices, thereby obtaining a medical tube with a uniform cross-section that meets the dimensional and precision requirements.

[0031] The medical tubing described in this invention refers to a series of tubing products in the medical field that play a crucial role in diagnosis, treatment, and surgery. Through specific designs, they facilitate the delivery of drugs, liquids, and gases, and support the normal operation of medical equipment. The design and production of medical tubing must strictly adhere to relevant standards to ensure its safety and effectiveness during use. Medical tubing, according to its application, can include, but is not limited to, diagnostic tubing, therapeutic tubing, and surgical tubing: diagnostic tubing, such as catheters and endoscopes, plays a vital role in disease diagnosis, helping doctors to visually understand the patient's internal condition; therapeutic tubing, such as infusion tubing and drainage tubing, is used to deliver drugs, nutritional solutions, etc., into the patient's body, or to drain accumulated fluids or pus; surgical tubing, such as endotracheal tubes and vascular catheters, assists breathing and blood circulation during surgery.

[0032] In this invention, unless otherwise specified, all numerical ranges include endpoint values. For example, a numerical range of 20% to 30% means that the point values ​​of 20% and 30% are included.

[0033] According to a preferred embodiment of the present invention, at least the following beneficial effects are achieved: This invention uses polyolefin elastomers as the main raw material to prepare high-performance medical tubing. This tubing possesses advantages such as solvent resistance and acid / alkali resistance, while also exhibiting high elasticity and long lifespan, balancing the advantages of plastics (solvent and acid / alkali resistance) with the advantages of rubber (high elasticity and long lifespan). Furthermore, this invention primarily uses polyolefin elastomers, with other components added in small amounts, yet the aforementioned high-performance medical tubing can be prepared by combining it with an extrusion molding process. This method also allows for the rational design of formulations to produce medical tubing products with different performance indicators tailored to various application conditions. The process of this invention is simple, low-cost, and suitable for large-scale production, representing a significant advancement in the preparation of high-end medical tubing materials in China. Attached Figure Description

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1This is a schematic diagram of the extrusion molding equipment in Embodiment 1 of the present invention; wherein, 1-feeding section, 2-extrusion section, 3-plasticizing section, 11-feeding cylinder, 12-screw, 13-die, 14-diverter shuttle, 15-core bar, 16-fixing device, 17-molding pipe, 18-cold water tank. Detailed Implementation

[0035] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0036] In the description of this invention, unless otherwise explicitly defined, terms such as extrusion molding process should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0037] In the description of this invention, references to terms such as "one embodiment," "some embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0038] Unless otherwise specified, the experimental methods used in the examples are conventional methods; unless otherwise specified, the materials and reagents used are commercially available. Example

[0039] In this embodiment, medical tube 1 was prepared, and the specific process is as follows: (1) Preparation / selection of polyolefin elastomer: Mix olefin (at least one of ethylene, propylene, ethylene-propylene copolymer) and 1-octene uniformly to form a copolymer elastomer, and obtain polyolefin elastomer; wherein, the mass percentage of 1-octene is 25%.

[0040] (2) Provide extrusion molding equipment, the structure of which is as follows: Figure 1 As shown. Figure 1 The extrusion molding equipment includes an extruder, an extruder head, a fixing device 16, and a cold water tank 18.

[0041] The extruder includes a feeding section 1, an extrusion section 2, and a plasticizing section 3 connected in sequence. The raw material is fed into the feeding section 1 through the feeding cylinder 11. The feeding section 1 is used to transport the raw material to the extrusion section 2. The extrusion section 2 and the plasticizing section 3 include a screw 12. The extrusion section 2 is used to compact and melt the material. The melting temperature is 100~195℃, and pressure is established. The function of the plasticizing section 3 is to extrude the melted material in the extrusion section 2 to the front end of the screw 12 in a quantitative and temperature-controlled manner.

[0042] The extruder head is connected to the end of the plasticizing section 3 furthest from the extrusion section 2. Its function is to change the molten material's spiral motion into a linear motion; to generate the necessary molding pressure to ensure the product is dense; and to further plasticize the material as it passes through the extruder head. The extruder head includes a die 13, a mandrel 15, and a flow divider 14. The mandrel 15 and the flow divider 14 are located inside the die 13, and the flow divider 14 is located at the port of the die 13 connected to the end of the plasticizing section 3 furthest from the extrusion section 2. The die 13 is used to mold the outer surface of the plastic part, and the mandrel 15 is used to mold the inner surface of the plastic part. The flow divider 14 is used to ensure the overall uniformity of pressure and temperature of the molten material in the extruder and to further enhance the plasticizing effect.

[0043] The fixing device 16 is located at the end of the die 13 away from the plasticizing section 3. The fixing device 16 is used to stabilize and correct the cross-sectional shape of the high-temperature plastic part extruded from the die 13 to form the molded tube 17. The cold water tank 18 is used to cool and shape the molded tube 17 to form the final product.

[0044] The polyolefin elastomer prepared in step (1) is added into the feed cylinder 11 of the extruder, and the extrusion molding process is carried out using the above-mentioned extrusion molding equipment (specifically, the above material is added into the feed cylinder 11, and under the action of the rotating extruder screw 12, the material is conveyed forward along the screw groove of the screw 12. During this process, it is continuously subjected to external heating and frictional heat, and gradually melts into a viscous flow state. Then, under the action of the extrusion section 2, the material melt passes through the extruder head die 13 with a certain shape and other auxiliary devices to obtain a tube with a uniform cross-section), thereby producing the medical tube 1. Example

[0045] In this embodiment, medical tube 2 was prepared, and the specific process is as follows: (1) Preparation of polyolefin elastomer: Ethylene and 1-octene are mixed evenly to form a copolymer elastomer, and polyolefin elastomer is obtained; wherein, the mass percentage of 1-octene is 30%.

[0046] (2) Provide extrusion molding equipment, the same as in Example 1. Add the polyolefin elastomer prepared in step (1) into the feed barrel of the extruder, and use the above-mentioned extrusion molding equipment to perform the extrusion molding process to prepare the medical tube 2. Example

[0047] In this embodiment, medical tube 3 was prepared, and the specific process is as follows: (1) Preparation of polyolefin elastomer: Ethylene and 1-butene are mixed evenly to form a copolymer elastomer, and polyolefin elastomer is obtained; wherein, the mass percentage of 1-butene is 30%.

[0048] (2) Provide extrusion molding equipment, the same as in Example 1. Add the polyolefin elastomer and anti-radiation agent prepared in step (1) into the feed cylinder of the extruder, and use the above-mentioned extrusion molding equipment to perform the extrusion molding process to prepare the medical tube 3, which has anti-radiation properties. Example

[0049] In this embodiment, medical tube 4 was prepared, and the specific process is as follows: (1) Preparation of polyolefin elastomer: Ethylene and 1-hexene are mixed evenly to form a copolymer elastomer to obtain polyolefin elastomer; wherein, the mass percentage of 1-hexene is 20%.

[0050] (2) Provide extrusion molding equipment, the same as in Example 1. By mass percentage, add the polyolefin elastomer and anti-aging agent prepared in step (1) into the feed cylinder of the extruder, and use the above-mentioned extrusion molding equipment to carry out the extrusion molding process to prepare medical tube 4, which has anti-aging function.

[0051] The compression set parameters of the medical tubing in Examples 1-4 were tested using the method in ASTM D395B standard at 70°C for 22 hours to characterize its elastic properties. The service life test conditions were a BT600S peristaltic pump at 600 RPM, room temperature, and no back pressure. Commercially available silicone tubing (medical-grade silicone tubing) was purchased from Shenzhen Jiajie Rubber & Plastics Co., Ltd. All other tests were conducted using conventional methods in the field to examine the mechanical properties and service life of the examples and commercially available medical tubing. The results are as follows:

[0052] To test the solvent resistance and acid / alkali resistance of the medical tube of this invention, the medical tube of Example 1 of this invention and a commercially available silicone tube were immersed in corresponding solutions at room temperature for 72 hours, and the percentage changes in mass and volume were measured. Mass change (%) = (m2-m1) / m1*100%, where m1 is the mass of the sample in air before immersion and m2 is the weight of the sample in air after immersion.

[0053] Volume change (%) = (m4-m3) / m3*100%, where m3 is the mass of the sample suspended in water before immersion, and m4 is the mass of the sample suspended in water after immersion.

[0054] The results are as follows:

[0055] The above experiments show that the medical tubes prepared in the above embodiments have excellent mechanical properties (including tensile strength, elongation, hardness, tear strength, etc.) and are resistant to various solvents and acids and alkalis.

[0056] The medical tubing of this invention is resistant to various solvents (including but not limited to toluene, xylene, alcohol, detergents, drying agents, etc.); resistant to various acids and alkalis (including but not limited to hydrochloric acid, sulfuric acid, nitric acid, caustic soda, soda water, etc.); and has excellent mechanical properties (including but not limited to density, tensile strength, elongation, tear strength, compression set, Shore hardness, glass transition temperature, dielectric constant, UL flame retardancy rating, etc.).

[0057] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A medical tube, characterized in that, The medical tube includes a polyolefin elastomer, which is a copolymer elastomer formed from olefins and high carbon α-olefins, wherein the high carbon α-olefins have a mass percentage of ≥20%.

2. The medical tube according to claim 1, characterized in that, The olefin is selected from at least one of ethylene, propylene, and ethylene-propylene copolymer, and / or the high carbon α-olefin is selected from at least one of 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene.

3. The medical tube according to claim 1, characterized in that, The high-carbon α-olefin is an α-olefin with ≥4 carbon atoms; preferably, the high-carbon α-olefin is an α-olefin with ≥4 carbon atoms and ≤10 carbon atoms.

4. The medical tube according to claim 1, characterized in that, The mass percentage of the high-carbon α-olefin is 20% to 30%.

5. The medical tube according to claim 1, characterized in that, The medical tube also includes an adjuvant, which is selected from at least one of anti-aging agents and anti-radiation agents.

6. The method for preparing the medical tube according to any one of claims 1 to 5, characterized in that, Includes the following steps: The polyolefin elastomer is added to an extruder, and the medical tube is prepared by extrusion molding.

7. The preparation method according to claim 6, characterized in that, The polyolefin elastomer and additives are mixed and added to the extruder, and the medical tube is prepared by the extrusion molding process.

8. The preparation method according to any one of claims 6 to 7, characterized in that, The extruder includes a feeding section, an extrusion section, and a plasticizing section connected in sequence; the melting temperature of the extrusion section is 100~195℃.

9. The preparation method according to claim 8, characterized in that, The extrusion molding process also uses an extruder head, a fixing device, and a cooling device; The extruder head includes a die, a mandrel, and a flow divider. The mandrel and the flow divider are disposed inside the die. The end of the die away from the plasticizing section is provided with a fixing device that can meet different size requirements.

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