PVC soft material and pump pipe joint made of PVC soft material

Abstract

The application belongs to the technical field of PVC material, and discloses a PVC soft material and a pump pipe joint made of the PVC soft material. The PVC soft material comprises PVC powder, a three-arm structure telechelic nano-structure polymer, vinyl chloride-vinyl acetate copolymer resin, acrylate-terminated urethane-based PCL polymer, a cross-linking agent, a plasticizer, a sensitizer, an antioxidant, a heat stabilizer and a dispersant. The three-arm structure telechelic nano-structure polymer, the vinyl chloride-vinyl acetate copolymer resin and the acrylate-terminated urethane-based PCL polymer are added to the material, and the materials are cross-linked under the action of the cross-linking agent, the plasticizer and other additives, so that the composite material system is more uniform, the mechanical properties of the material are better, the insoluble particle test meets the standard, the material is suitable for medical catheters, can meet the requirements of blood purification, and will not affect the material properties due to the softening solvent and heat sterilization as a medical pump pipe.

Description

Technical Field

[0001] This invention relates to the field of PVC material technology, specifically to a flexible PVC material and a pump pipe fitting made of the flexible PVC material. Background Technology

[0002] Polyvinyl chloride (PVC) is a polymer formed by the polymerization of vinyl chloride monomer (VCM) through a free radical polymerization mechanism under the action of initiators such as peroxides and azo compounds, or under the influence of light and heat. PVC resin is widely used due to its unparalleled advantages over other materials, such as good chemical stability, simple processing, and excellent biocompatibility. However, in the mid-1970s, it was recognized that residual vinyl chloride monomer (VCM) in PVC resin and products was a serious carcinogen, which would affect the development of PVC to some extent. Later, researchers successfully reduced residual VCM by adding spiral plate heat exchangers, achieving a VCM content of less than 10 ppm in PVC resin, meeting the requirements for sanitary grade resin and expanding the application range of PVC.

[0003] Medical catheters are a general term for tubular products that connect the inside and outside of the human body, made of various materials such as metal, plastic, and rubber. Pump catheters, especially those with integrated vibration pumps, are frequently used in extracorporeal blood circulation to deliver blood, such as during hemodialysis, to provide appropriate short-term treatment to patients by delivering blood at a suitable flow rate. The primary raw material for medical catheters is PVC. Although current PVC materials meet sanitary resin requirements, medical catheters, especially medical pump catheters used in extracorporeal blood circulation, have higher performance requirements for PVC materials. For example, they must possess high flexibility to prevent twisting and the formation of narrow bending radii that would prevent fluid delivery. Ordinary PVC tubing cannot be used as medical pump tubing due to its poor flexibility, poor resilience, and solvent intolerance. It also cannot be used as pump tubing because it deforms during heat sterilization, and its mechanical properties are adversely affected. Therefore, to prevent PVC from being phased out of the medical catheter field, it is necessary to develop a safe and harmless flexible PVC material suitable for use as pump tubing. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a flexible PVC material and a pump tube connector made of the flexible PVC material. The flexible PVC material of this invention incorporates a three-armed telescopic nanostructure polymer, vinyl chloride-vinyl acetate copolymer resin, and acrylate-terminated urethane-based PCL polymer, which crosslink with PVC under the action of crosslinking agents, plasticizers, and other additives. This makes the composite material system more uniform, improves the material's mechanical properties, and meets the standards for insoluble particulate matter testing. It is suitable as a medical catheter, meets the requirements of blood purification, and as a medical pump tube, its material properties are not affected by softening solvents or heat sterilization.

[0005] To achieve the objectives of this invention, the PVC flexible material of this invention comprises PVC powder, a three-armed telescopic nanostructure polymer, vinyl chloride-vinyl acetate copolymer resin, acrylate-terminated urethane-based PCL polymer, a crosslinking agent, a plasticizer, a sensitizer, an antioxidant, a heat stabilizer, and a dispersant.

[0006] Furthermore, in some embodiments of the invention, the PVC flexible material comprises, by weight, 50-60 parts of PVC powder, 15-25 parts of a three-armed telescopic nanostructure polymer, 10-20 parts of vinyl chloride-vinyl acetate copolymer resin, 10-20 parts of acrylate-terminated urethane PCL polymer, 0.6-4 parts of crosslinking agent, 15-35 parts of plasticizer, 1.5-3.5 parts of sensitizer, 0.5-3 parts of antioxidant, 2-5 parts of heat stabilizer, and 0.5-3 parts of dispersant.

[0007] Furthermore, in some embodiments of the present invention, the three-armed teleclaw-type nanostructure polymer is selected from one or more of teleclaw polyurea TP3, TP4, and TP5.

[0008] Furthermore, in some embodiments of the invention, the vinyl chloride-vinyl acetate copolymer resin contains 7-14% vinyl acetate.

[0009] Furthermore, in some embodiments of the present invention, the acrylate-terminated urethane-based PCL polymer is UPCL-2, an acrylate-terminated urethane-based PCL polymer.

[0010] Furthermore, in some embodiments of the present invention, the crosslinking agent is selected from one or more of dicumyl peroxide, benzoyl peroxide, and dodecyl peroxide, and one or more of azobisisobutyronitrile, azobisisoheptanenitrile, and dimethyl azobisisobutyrate; preferably benzoyl peroxide and azobisisoheptanenitrile; more preferably, the mass ratio of benzoyl peroxide to azobisisoheptanenitrile is 1:1-2.

[0011] Furthermore, in some embodiments of the invention, the plasticizer is one or more of dioctyl phthalate, trioctyl trimellitate, dioctyl terephthalate, and epoxidized soybean oil; preferably dioctyl terephthalate and epoxidized soybean oil; more preferably, the mass ratio of dioctyl terephthalate to epoxidized soybean oil is 3-5:1.

[0012] Furthermore, in some embodiments of the invention, the sensitizer is one or more of trimethylolpropane triacrylate (TMPTA), melamine trienolide (TAIC), melamine propargyl acrylate (TAC), and trimethylolpropane trimethacrylate (TMPTM).

[0013] Furthermore, in some embodiments of the invention, the antioxidant is one or more of antioxidant 1010, antioxidant 245, antioxidant 1076, antioxidant 168, antioxidant 1098, antioxidant B225, antioxidant B215, and antioxidant B900.

[0014] Furthermore, in some embodiments of the invention, the heat stabilizer is one or more of calcium-zinc composite stabilizer, lead stearate, and zinc stearate; preferably, in some embodiments of the invention, the heat stabilizer is a calcium-zinc composite stabilizer, and more preferably, the weight ratio of calcium to zinc in the calcium-zinc composite stabilizer is 1.5-2:1.

[0015] Furthermore, in some embodiments of the present invention, the dispersant is selected from one or more of polyethylene wax, oxidized polyethylene wax, oleamide, stearamide, palmitamide, and ethylene bis-stearamide; preferably, in some embodiments of the present invention, the dispersant is polyethylene wax.

[0016] On the other hand, the present invention also provides a method for preparing the aforementioned PVC flexible material. The method is as follows: the crosslinking agent and plasticizer are premixed and then mixed with PVC powder, a three-armed telescopic nanostructure polymer, vinyl chloride-vinyl acetate copolymer resin, acrylate-terminated urethane PCL polymer, heat stabilizer and antioxidant, and added to an extruder for melt kneading. Then, a dispersant and a sensitizer are added from the feed port in the middle section of the extruder, and the mixture is extruded and granulated to obtain the final product.

[0017] In another aspect, the present invention also provides a pump pipe connector made of the aforementioned PVC flexible material. The preparation method of the pump pipe connector is as follows: the PVC flexible material is molded by injection molding to form a pump pipe connector, the pump pipe connector is cross-linked under an electron beam irradiation dose of 20-60 kGy, and the part of the pump pipe connector used for bonding the pump pipe is treated with a softener.

[0018] Furthermore, in some embodiments of the invention, the PVC softener comprises a primary softener, a co-softening agent, and a penetrant; preferably, the PVC softener comprises, by weight fraction, 15-55 parts of the primary softener, 0-35 parts of the co-softening agent, and 30-60 parts of the penetrant; preferably, the primary softener is selected from one or more of toluene, THF, cyclohexanone, and dichloromethane, the co-softening agent is selected from one or more of methanol, ethanol, and ethyl acetate, and the penetrant is selected from one or more of formic acid, acetic acid, and citric acid.

[0019] Compared with the prior art, the advantages of the present invention are as follows:

[0020] (1) In this invention, dioctyl terephthalate and epoxidized soybean oil are used as composite plasticizers. Epoxidized soybean oil can not only increase the mobility of PVC molecular chains and reduce the crystallinity of molecular chains, thus enhancing its plasticity and flexibility, but also improve the stability of the material so that its performance will not be affected by softening solvents or heat sterilization.

[0021] (2) In addition to PVC, this invention also includes materials such as a three-armed telescopic nanostructure polymer, vinyl chloride-vinyl acetate copolymer resin, and acrylate-terminated urethane-based PCL polymer. Under the action of the composite crosslinking agent, plasticizer and other additives of this invention, these materials have excellent compatibility, meet the insoluble particulate test standards, and will not produce or precipitate substances harmful to the human body. They also form dendritic and network structures, which to a certain extent restrict the slippage between molecular chains, maximize the mechanical properties and resilience of the materials, and can quickly recover their shape after being compressed.

[0022] (3) When the PVC soft material obtained by the present invention is used to make pump pipe joints, the chemical bonds are broken under the irradiation of high-energy rays, and free radicals are generated. The free radicals on PVC combine with the active groups of the sensitizer to form new chemical bonds, so that the PVC material forms a certain degree of three-dimensional cross-linked structure. The existence of the cross-linked structure makes the pump pipe joint only swell and not dissolve when treated with a softener, and has excellent stability. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. It should be understood that the following description is merely illustrative and not intended to limit the invention.

[0024] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1 to 5” is disclosed, the described range should be interpreted as including the ranges “1 to 4”, “1 to 3”, “1 to 2”, “1 to 2 and 4 to 5”, “1 to 3 and 5”, etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range.

[0025] The singular form includes the plural objects of discussion unless the context clearly indicates otherwise. "Optional" or "any one" means that the matter or event described thereafter may or may not occur, and the description includes both the possibility that the event occurs and the possibility that the event does not occur.

[0026] The indefinite articles “a” and “an” preceding an element or component of this invention do not impose any limitation on the quantity (i.e., number of times) of the element or component. Therefore, “an” or “a” should be interpreted as including one or at least one, and the singular form of an element or component also includes the plural form, unless the quantity clearly refers only to the singular form.

[0027] Furthermore, the terms "one embodiment," "some implementations," "example," "specific example," or "some examples," etc., described below refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms are not necessarily directed at the same embodiment or example. Moreover, the technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

[0028] The VCM content in the polyvinyl chloride resin of this invention is less than 10 ppm. Unless otherwise specified, the three-armed telechelic nanostructure polymer in the specific embodiments of this invention is telechelic polyurea TP5; the acrylate-terminated urethane-based PCL polymer is acrylate-terminated urethane-based PCL polymer UPCL-2; the vinyl chloride-vinyl acetate copolymer resin has a vinyl acetate content of 7-14%; the sensitizer is trimethylolpropane trimethacrylate (TMPTM); the dispersant is polyethylene wax; the antioxidant is antioxidant 1010; the preparation method of the PVC soft material is as follows: the crosslinking agent and plasticizer are premixed, and then mixed with PVC powder, the three-armed telechelic nanostructure polymer, the vinyl chloride-vinyl acetate copolymer resin, the acrylate-terminated urethane-based PCL polymer, the heat stabilizer and the antioxidant, and added to an extruder for melt kneading. Then, the dispersant and sensitizer are added from the feed port in the middle section of the extruder, and the mixture is extruded and granulated to obtain the final product.

[0029] Example 1

[0030] A flexible PVC material, comprising, by weight, 60 parts of PVC powder, 25 parts of a three-armed telescopic nanostructure polymer, 20 parts of vinyl chloride-vinyl acetate copolymer resin, 20 parts of acrylate-terminated urethane-based PCL polymer, 4 parts of crosslinking agent, 35 parts of plasticizer, 3 parts of sensitizer, 3 parts of antioxidant, 5 parts of heat stabilizer, and 3 parts of dispersant.

[0031] The crosslinking agent is benzoyl peroxide and azobisisobutyronitrile, with a mass ratio of benzoyl peroxide to azobisisobutyronitrile of 1:2; the plasticizer is dioctyl terephthalate and epoxidized soybean oil, with a mass ratio of dioctyl terephthalate to epoxidized soybean oil of 5:1; the heat stabilizer is a calcium-zinc composite stabilizer, with a weight ratio of calcium to zinc of 1.5:1.

[0032] The aforementioned PVC flexible material is prepared as follows: the crosslinking agent and plasticizer are premixed and then mixed with PVC powder, a three-armed telescopic claw-type nanostructure polymer, vinyl chloride-vinyl acetate copolymer resin, acrylate-terminated urethane-based PCL polymer, heat stabilizer and antioxidant, and added to an extruder for melt kneading. Then, the dispersant and sensitizer are added from the feed port in the middle section of the extruder, and the material is extruded and granulated to obtain the final product.

[0033] Example 2

[0034] A flexible PVC material, differing from Example 1, comprises, by weight, 55 parts of PVC powder, 20 parts of a three-armed telescopic nanostructure polymer, 15 parts of vinyl chloride-vinyl acetate copolymer resin, 15 parts of acrylate-terminated urethane-based PCL polymer, 3 parts of crosslinking agent, 25 parts of plasticizer, 2.5 parts of sensitizer, 2 parts of antioxidant, 3.5 parts of heat stabilizer, and 2 parts of dispersant.

[0035] The crosslinking agent is benzoyl peroxide and azobisisobutyronitrile, with a mass ratio of benzoyl peroxide to azobisisobutyronitrile of 1:2; the plasticizer is dioctyl terephthalate and epoxidized soybean oil, with a mass ratio of dioctyl terephthalate to epoxidized soybean oil of 4:1; and the heat stabilizer is a calcium-zinc composite stabilizer, with a weight ratio of calcium to zinc of 2:1.

[0036] Example 3

[0037] A flexible PVC material, differing from Example 1, comprises, by weight, 50 parts of PVC powder, 15 parts of a three-armed telescopic nanostructure polymer, 10 parts of vinyl chloride-vinyl acetate copolymer resin, 10 parts of acrylate-terminated urethane-based PCL polymer, 1 part of a crosslinking agent, 20 parts of a plasticizer, 1.5 parts of a sensitizer, 0.5 parts of an antioxidant, 2 parts of a heat stabilizer, and 1 part of a dispersant.

[0038] The crosslinking agent is benzoyl peroxide and azobisisobutyronitrile, with a mass ratio of benzoyl peroxide to azobisisobutyronitrile of 1:1; the plasticizer is dioctyl terephthalate and epoxidized soybean oil, with a mass ratio of dioctyl terephthalate to epoxidized soybean oil of 3:1; the heat stabilizer is a calcium-zinc composite stabilizer, with a weight ratio of calcium to zinc of 1.5:1.

[0039] Example 4

[0040] A flexible PVC material, differing from Example 2, comprises, by weight, 55 parts of PVC powder, 15 parts of vinyl chloride-vinyl acetate copolymer resin, 15 parts of acrylate-terminated urethane-based PCL polymer, 3 parts of crosslinking agent, 25 parts of plasticizer, 2.5 parts of sensitizer, 2 parts of antioxidant, 3.5 parts of heat stabilizer, and 2 parts of dispersant.

[0041] Example 5

[0042] A flexible PVC material, differing from Example 2, comprises, by weight, 55 parts of PVC powder, 20 parts of a three-armed telescopic nanostructure polymer, 15 parts of an acrylate-terminated urethane-based PCL polymer, 3 parts of a crosslinking agent, 25 parts of a plasticizer, 2.5 parts of a sensitizer, 2 parts of an antioxidant, 3.5 parts of a heat stabilizer, and 2 parts of a dispersant.

[0043] Example 6

[0044] A flexible PVC material, differing from Example 2, comprises, by weight, 55 parts of PVC powder, 20 parts of a three-armed telescopic nanostructure polymer, 15 parts of vinyl chloride-vinyl acetate copolymer resin, 3 parts of crosslinking agent, 25 parts of plasticizer, 2.5 parts of sensitizer, 2 parts of antioxidant, 3.5 parts of heat stabilizer, and 2 parts of dispersant.

[0045] Example 7

[0046] A flexible PVC material, which differs from Example 2 in that the crosslinking agent is azobisisobutyronitrile.

[0047] Example 8

[0048] A flexible PVC material, which differs from Example 2 in that the plasticizer is dioctyl terephthalate.

[0049] Example 9

[0050] Pump pipe fittings were prepared using the PVC flexible material obtained in Example 2. The preparation method was as follows: the PVC flexible material was molded into a pump pipe fitting through injection molding. The pump pipe fitting was then cross-linked under an electron beam irradiation dose of 20-60 kGy. The parts of the pump pipe fitting used for bonding the pump pipe were treated with a softener. The PVC softener contained, by weight fraction, 35 parts of the main softener cyclohexanone, 15 parts of the auxiliary softener ethanol, and 40 parts of the penetrant citric acid. The pump pipe fittings obtained after treatment with this softener did not show significant changes in mechanical properties and resilience compared to the PVC flexible material used, indicating that the PVC flexible material used was not affected by softening solvents or heat, and was suitable for preparing pump pipe fittings.

[0051] Effect test

[0052] The tensile strength, elongation at break, elastic deformation recovery rate, and particle exudation properties of the PVC flexible materials obtained in Examples 1-8 were tested, and the test results are shown in Table 1.

[0053] Among them: (1) Tensile strength and elongation at break are prepared and tested in accordance with ISO 527 requirements; (2) Elastic deformation recovery rate is tested using DMA (test method: after the sample is heated to 60°C, an external force is applied to make the sample deform by 120%, and under the mechanical load, it is cooled to 0°C at a temperature gradient of 15K / min and held for 10min. Then the external force is removed, and the temporary shape of the sample is fixed. Then the temperature is raised to 60°C at a rate of 15K / min and held for 10min. The sample returns to its original shape); (3) Insoluble particle test is performed in accordance with the method specified in the standard "Test Method for Insoluble Particles of Packaging Materials" to determine the number of insoluble particles larger than 10μm.

[0054] Table 1 Material properties obtained from each embodiment

[0055]

[0056] As can be seen from the above embodiments, the PVC flexible material of the present invention, with the addition of PVC, a three-armed telescopic nanostructure polymer, vinyl chloride-vinyl acetate copolymer resin, acrylate-terminated urethane-based PCL polymer, and other materials, exhibits excellent compatibility under the action of composite crosslinking agents, plasticizers, and other additives. The insoluble particulate matter test meets the standards, and the mechanical properties and resilience of the material are maximized. It is suitable as a medical catheter, can meet the requirements of blood purification, and as a medical pump tube, its material properties will not be affected by softening solvents or heat sterilization.

[0057] Those skilled in the art will readily understand that the above description is merely an embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A flexible PVC material, characterized in that, The PVC flexible material comprises, by weight, 50-60 parts PVC powder, 15-25 parts a three-armed telescopic nanostructured polymer, 10-20 parts vinyl chloride-vinyl acetate copolymer resin, 10-20 parts acrylate-terminated urethane PCL polymer, 0.6-4 parts crosslinking agent, 15-35 parts plasticizer, 1.5-3.5 parts sensitizer, 0.5-3 parts antioxidant, 2-5 parts heat stabilizer, and 0.5-3 parts dispersant; the crosslinking agent is benzoyl peroxide and... The polymer is composed of azobisisobutyronitrile (DIRT-H), wherein the mass ratio of benzoyl peroxide to DIRT-H is 1:1-2; the plasticizer is dioctyl terephthalate and epoxidized soybean oil, wherein the mass ratio of dioctyl terephthalate to epoxidized soybean oil is 3-5:1; the three-armed telechelic nanostructure polymer is selected from one or more of telechelic polyurea TP3, TP4, and TP5; and the acrylate-terminated urethane-based PCL polymer is acrylate-terminated urethane-based PCL polymer UPCL-2.

2. The PVC flexible material according to claim 1, characterized in that, The vinyl chloride-vinyl acetate copolymer resin contains 7-14% vinyl acetate.

3. The PVC flexible material according to claim 1, characterized in that, The sensitizer is one or more of trimethylolpropane triacrylate, triallyl cyanurate, and trimethylolpropane trimethacrylate.

4. The PVC flexible material according to claim 1, characterized in that, The antioxidant is one or more of antioxidant 1010, antioxidant 245, antioxidant 1076, antioxidant 168, antioxidant 1098, antioxidant B225, antioxidant B215, and antioxidant B900.

5. The PVC flexible material according to claim 1, characterized in that, The heat stabilizer is one or more of calcium-zinc composite stabilizer, lead stearate, and zinc stearate.

6. The PVC flexible material according to claim 1, characterized in that, The heat stabilizer is a calcium-zinc composite stabilizer.

7. The PVC flexible material according to claim 6, characterized in that, The calcium-zinc composite stabilizer has a calcium-to-zinc element weight ratio of 1.5-2:

1.

8. The PVC flexible material according to claim 1, characterized in that, The dispersant is selected from one or more of polyethylene wax, oxidized polyethylene wax, oleamide, stearamide, palmitamide, and ethylene bis-stearamide.

9. The PVC flexible material according to claim 1, characterized in that, The dispersant is polyethylene wax.

10. The pump pipe fitting made of the PVC flexible material according to any one of claims 1-9, characterized in that, The preparation method of the pump pipe joint is as follows: the PVC soft material is molded by injection molding to form a pump pipe joint, the pump pipe joint is cross-linked under an electron beam irradiation dose of 20-60kGy, and the part of the pump pipe joint used for bonding the pump pipe is treated with a softener.

11. The pump pipe joint according to claim 10, characterized in that, The softener contains a primary softener, a co-softening agent, and a penetrant.

12. The pump pipe joint according to claim 11, characterized in that, The softener comprises, by weight fraction, 15-55 parts of main softener, 0-35 parts of auxiliary softener, and 30-60 parts of penetrant.

13. The pump pipe joint according to claim 11, characterized in that, The primary softening agent is selected from one or more of toluene, THF, cyclohexanone, and dichloromethane; the auxiliary softening agent is selected from one or more of methanol, ethanol, and ethyl acetate; and the penetrant is selected from one or more of formic acid, acetic acid, and citric acid.

Images