Antibacterial medical PVC material and preparation method thereof

Abstract

The invention relates to the technical field of PVC materials, in particular to an antibacterial medical PVC material and a preparation method thereof. The antibacterial medical PVC material is prepared from the following raw materials in parts by weight: 70 to 100 parts by weight of PVC resin, 10 to 30 parts by weight of plasticizer, 8 to 16 parts by weight of filler, 2 to 4 parts by weight of stabilizer, 1 to 3 parts by weight of coupling agent, 0.5 to 2 parts by weight of lubricant, 1 to 3 parts by weight of epoxy linseed oil, 0.2 to 0.8 part by weight of antioxidant 1010 and 5 to 12 parts by weight of antibacterial composite additive. The adopted antibacterial composite additive is formed by compounding an antibacterial agent and modified graphene, the prepared medical PVC material has good antibacterial performance and mechanical performance, meanwhile, the technological operation is simple, the production cost is low, meanwhile, the medical PVC material has good processing performance, the application prospect is wide, and the medical PVC material is suitable for popularization and application. The method is widely applied to the field of medical application.

Description

Technical Field

[0001] The invention relates to the technical field of PVC materials, and in particular to an antibacterial medical PVC material and a preparation method thereof. Background Art

[0002] In recent years, the medical plastics industry has attracted much attention for its high added value, high growth rate and broad market potential. Polyvinyl chloride (PVC) can be made into disposable medical supplies such as blood storage bags, infusion equipment, respiratory masks, enteral and parenteral nutrition tubes, extracorporeal circulation circuits, membrane oxygenators and hemodialysis circuits due to its good mechanical properties, cold resistance, softness, inertness, high transparency, easy sterilization and high strength, and is widely used in clinical practice.

[0003] Medical PVC materials are plastics with special uses. When made into different medical devices, they may come into contact with biological blood, body and body fluids for a long time. Some devices with special functions may be implanted in the body. The quality of medical PVC materials is directly related to human life and health. Therefore, medical PVC materials have very strict requirements.

[0004] Antibacterial medical PVC materials are made by adding antibacterial agents to the PVC matrix. These antibacterial agents can form an antibacterial layer on the surface of the material, effectively inhibiting or killing bacteria, fungi and viruses that come into contact with it. The selection of antibacterial agents is crucial. They need to have good biocompatibility, high efficiency and long-lasting antibacterial effects, and will not cause drug resistance problems during long-term use.

[0005] Researchers have explored a variety of antimicrobial agents, including metal ions (such as silver and copper), organic antimicrobial agents (such as quaternary ammonium salts), natural antimicrobial substances (such as chitosan) and nanocomposites, etc. These antimicrobial agents achieve antimicrobial effects by destroying the cell membrane of microorganisms, inhibiting enzyme activity or interfering with DNA replication through different mechanisms.

[0006] The preparation method of antibacterial medical PVC materials, the selection of antibacterial agents, the testing and evaluation of antibacterial properties, and the evaluation of biocompatibility of materials are all important research contents. In addition, how to ensure the uniform distribution of antibacterial agents in PVC materials, improve the durability of antibacterial effects, reduce material costs, and improve the mechanical properties of materials are also technical challenges in patent development. The research and development of antibacterial medical PVC materials is of great significance to improving the safety of medical equipment, reducing hospital infections, and improving public health levels. With the continuous emergence of new materials and new technologies, the innovation and application prospects of antibacterial medical PVC materials are broad. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides an antibacterial medical PVC material and a preparation method thereof.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: An antibacterial medical PVC material is composed of the following raw materials in parts by weight: 70-100 parts by weight of PVC resin, 10-30 parts by weight of plasticizer, 8-16 parts by weight of filler, 2-4 parts by weight of stabilizer, 1-3 parts by weight of coupling agent, 0.5-2 parts by weight of lubricant, 1-3 parts by weight of epoxy linseed oil, 0.2-0.8 parts by weight of antioxidant 1010, and 5-12 parts by weight of antibacterial composite additive.

[0009] The plasticizer is one or any combination of trioctyl citrate, di(2-ethylhexyl) phthalate, butyl epoxy furoate, and methyl epoxy acetylinoleate; preferably, the plasticizer is a mixture of trioctyl citrate and methyl epoxy acetylinoleate in a mass ratio of (0.8-1.4):1.

[0010] The filler is one or any combination of silicon dioxide, titanium dioxide, montmorillonite and talc.

[0011] The stabilizer is one or any combination of calcium stearate, zinc laurate, and stearylbenzoylmethane; preferably, the stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of (1-3):1.

[0012] The coupling agent is one or any combination of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent.

[0013] The lubricant is one or any combination of stearic acid, glyceryl monostearate, polypropylene wax, and polyethylene wax.

[0014] As a two-dimensional material with excellent physical and chemical properties, graphene has broad application prospects in medical PVC (polyvinyl chloride). However, due to the poor biocompatibility of graphene in PVC materials, poor dispersion, easy aggregation, and uneven distribution, which affects the overall performance of PVC materials, using it directly as an additive may reduce its mechanical properties, so it needs to be modified.

[0015] Eugenol is a natural ingredient with excellent antibacterial and sedative effects. Compared with other antibacterial ingredients, it is greener, more environmentally friendly and safer. Chlorhexidine can effectively inhibit the growth of various bacteria, fungi and certain viruses, including Gram-positive bacteria and Gram-negative bacteria, and can form an antibacterial layer on the surface of the material, providing lasting antibacterial protection, reducing the risk of medical device-related infection, and making it an ideal antibacterial ingredient in medical equipment and materials. The present invention connects eugenol with p-bromobenzaldehyde and chlorhexidine, so that the final product has a higher antibacterial effect at the same time, and is prepared by a "one-pot" method, which is simple to operate and has a high yield.

[0016] The invention uses an alkenyl-containing silane coupling agent to modify graphene, which can improve the dispersion performance of graphene in PVC materials and the compatibility, thereby improving the overall mechanical properties of the PVC materials. On the other hand, the carbon-carbon double bonds in the alkenyl silane coupling agent are introduced into the graphene, which can effectively react with the carbon-carbon double bonds in the eugenol antibacterial agent to obtain an antibacterial composite additive, which is added to the PVC material as a whole to more effectively improve the mechanical properties and antibacterial properties of the material, avoid the problem of uneven dispersion in the PVC material due to the graphene suspension phenomenon, and avoid the problem of poor compatibility of the graphene and the antibacterial agent added alone, and at the same time, the performance of the PVC material is better than that of the graphene or the antibacterial agent added alone.

[0017] The obtained antibacterial composite additive has the following advantages: (1) The modification of the silane coupling agent improves the interfacial bonding force between graphene and the PVC matrix, which helps to evenly disperse the graphene in the PVC matrix and avoid agglomeration, thereby improving the uniformity and performance of the composite material. The addition of the eugenol antibacterial agent may further improve this bonding by promoting further dispersion of the graphene sheets and avoiding agglomeration, thereby further improving the mechanical strength of the composite material; (2) The combination of the eugenol antibacterial agent and chlorhexidine provides a broad-spectrum antibacterial effect, which can effectively inhibit the growth of a variety of microorganisms. When combined with the modified graphene, it can synergistically The effect is to increase the antibacterial performance, improve the antibacterial efficiency and make the antibacterial effect more lasting. At the same time, the two can also complement each other in the antibacterial mechanism. The eugenol antibacterial agent may work by destroying the bacterial cell membrane, while the modified graphene may work by physical adsorption and restricting bacterial activity. (3) The addition of modified graphene can improve the stress distribution in PVC materials, and the eugenol antibacterial agent may enhance this effect by increasing the intermolecular force, which can increase the dispersion and stability of graphene in PVC materials, thereby increasing the filling amount of inorganic materials in the resin and improving the toughness and impact resistance of the material.

[0018] The preparation method of the antibacterial composite additive is as follows: S1: mixing p-bromobenzaldehyde, chlorhexidine, eugenol and N,N-dimethylformamide, adding ferric chloride, heating and stirring to obtain eugenol antibacterial agent; S2, mixing graphene and ethanol aqueous solution and ultrasonically dispersing them, adding silane and heating them to obtain modified graphene; S3, in a nitrogen environment, the modified graphene, sodium dodecyl sulfate, eugenol antibacterial agent and N,N-dimethylformamide, and stirred evenly, and then azobisisobutyl cyanide was added, and heated to react to obtain an antibacterial composite additive.

[0019] Specific reaction mechanism: S1 uses p-bromobenzaldehyde, chlorhexidine and eugenol as the main raw materials for the reaction, N,N-dimethylformamide as the reaction solvent, and ferric chloride as the catalyst. Under heating, the amino group in chlorhexidine, the aldehyde group in p-bromobenzaldehyde and the hydrogen in eugenol undergo addition substitution reaction to obtain an antibacterial agent containing eugenol; S2 uses graphene and silane as the reaction raw materials. Under heating and stirring conditions, the silane coupling agent can react with the oxygen groups on the surface of graphene to form a stable silicon-oxygen bond, thereby modifying the graphene; S3 uses silane-modified graphene and eugenol antibacterial agent as reaction raw materials, and azobisisobutylcyanide as the initiator. The double bonds in the silane-modified graphene and the double bonds in the eugenol antibacterial agent undergo addition reaction to finally obtain an antibacterial composite additive.

[0020] Preferably, the preparation method of the antibacterial composite additive is as follows: S1: 3-6 parts by weight of p-bromobenzaldehyde, 4-8 parts by weight of chlorhexidine, 4-8 parts by weight of eugenol and 70-120 parts by weight of N,N-dimethylformamide are mixed and stirred evenly, 0.1-0.6 parts by weight of ferric chloride are added, and the mixture is stirred at 75-85° C. and 300-500 rpm for 8-16 hours; after the reaction is completed, the solvent is removed by distillation to obtain a eugenol antibacterial agent; S2, 4-8 parts by weight of graphene and 60-100 parts by weight of 50-70wt% ethanol aqueous solution are mixed and placed Ultrasonic dispersion is performed at an ultrasonic power of 200-600 W and an ultrasonic frequency of 40-80 kHz for 20-50 min, 0.5-2 parts by weight of silane is added, and the mixture is stirred at 50-70° C. and 300-500 rpm for 1-3 h, and filtered, washed, and dried to obtain modified graphene; S3, under nitrogen environment, 3-5 parts by weight of the modified graphene, 0.5-2 parts by weight of dodecyl Sodium sulfate, 3-6 parts by weight of eugenol antibacterial agent and 80-140 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.5-1 parts by weight of azobisisobutylcyanide are added, and the mixture is reacted at 70-80° C. and 400-800 rpm for 3-6 hours. After the reaction is completed, the mixture is filtered, washed and dried to obtain an antibacterial composite additive.

[0021] Preferably, the silane in S2 is a silane coupling agent containing an alkenyl group.

[0022] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 300-600rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 120-160°C, discharging the material after the material temperature reaches 45-55°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 220-260°C, the die head temperature is 250-270°C, and the screw rotation speed is 300-600rpm to obtain the antibacterial medical PVC material.

[0023] Beneficial effects of the present invention: The present invention provides an antibacterial medical PVC material and a preparation method thereof, wherein an antibacterial composite additive is added to the raw material formula of the antibacterial medical PVC material. The antibacterial composite additive prepared by the present invention can not only improve the dispersion performance of graphene in PVC materials, but also improve the interfacial bonding force between graphene and the PVC matrix. The eugenol antibacterial agent may enhance this effect by increasing the intermolecular force, thereby increasing the dispersion and stability of graphene in PVC materials, thereby improving the toughness and impact resistance of the material. Conversely, the addition of graphene can further synergistically increase the antibacterial performance, improve the antibacterial efficiency and more lasting antibacterial effect. Therefore, the medical PVC material prepared by the present invention has good antibacterial performance and mechanical properties. At the same time, the process of the present invention is simple to operate, and the production cost is low. At the same time, it has good processing performance, broad application prospects, and has a wide range of applications in the field of medical applications. DETAILED DESCRIPTION

[0024] The above content of the present invention is further described in detail below in conjunction with specific implementation modes, but this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments.

[0025] Introduction of some raw materials in this application: PVC resin was purchased from Qingdao Longshengxiang Chemical Co., Ltd., item number: 001.

[0026] Graphene was purchased from Jianshi Mineral Powder Factory in Lingshou County, with a particle size / mesh size of 2000 mesh.

[0027] Example 1 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 80 parts by weight of PVC resin, 20 parts by weight of plasticizer, 10 parts by weight of filler, 3 parts by weight of stabilizer, 2 parts by weight of coupling agent, 1 part by weight of lubricant, 2 parts by weight of epoxy linseed oil, 0.5 parts by weight of antioxidant 1010, and 8 parts by weight of antibacterial composite additives.

[0028] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 1:1.

[0029] The filler is silicon dioxide.

[0030] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 2:1.

[0031] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0032] The lubricant is stearic acid.

[0033] The preparation method of the antibacterial composite additive is as follows: S1 4 parts by weight of p-bromobenzaldehyde, 6 parts by weight of chlorhexidine and 6 parts by weight of eugenol and 80 parts by weight of N, N-dimethylformamide was mixed and stirred evenly, 0.5 parts by weight of ferric chloride was added, and stirred at 78°C and 400 rpm for 10 hours; after the reaction was completed, the solvent was removed by distillation to obtain a eugenol antibacterial agent; S2, 6 parts by weight of graphene and 80 parts by weight of 60wt% ethanol aqueous solution were mixed and placed under ultrasonic power. Ultrasonic dispersion was performed at a power of 400 W and an ultrasonic frequency of 70 kHz for 30 min, 1 part by weight of (acryloyloxymethyl)phenylethyltrimethoxysilane was added, and the mixture was stirred at 60° C. and 400 rpm for 1.5 h, filtered, washed, and dried to obtain modified graphene; S3, under nitrogen environment, 4 parts by weight of the modified graphene and 1 part by weight of sodium dodecyl sulfate , 5 parts by weight of eugenol antibacterial agent and 100 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.8 parts by weight of azobisisobutyl cyanide are added, and the mixture is reacted at 75°C and 600rpm for 4 hours. After the reaction is completed, the mixture is filtered, washed, and dried to obtain an antibacterial composite additive.

[0034] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 500 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 140°C, discharging the material after the material temperature reaches 50°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 240°C, the die head temperature is 260°C, and the screw rotation speed is 400 rpm to obtain the antibacterial medical PVC material.

[0035] Example 2 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 70 parts by weight of PVC resin, 10 parts by weight of plasticizer, 8 parts by weight of filler, 2 parts by weight of stabilizer, 1 part by weight of coupling agent, 0.5 parts by weight of lubricant, 1 part by weight of epoxy linseed oil, 0.2 parts by weight of antioxidant 1010, and 5 parts by weight of antibacterial composite additives.

[0036] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 0.8:1.

[0037] The filler is silicon dioxide.

[0038] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 1:1.

[0039] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0040] The lubricant is stearic acid.

[0041] The preparation method of the antibacterial composite additive is as follows: S1: 3 parts by weight of p-bromobenzaldehyde, 4 parts by weight of chlorhexidine, 4 parts by weight of eugenol and 70 parts by weight of N, N-dimethylformamide was mixed and stirred evenly, 0.1 parts by weight of ferric chloride was added, and the mixture was stirred at 75°C and 300 rpm for 8 hours; after the reaction was completed, the solvent was removed by distillation to obtain a eugenol antibacterial agent; S2, 4 parts by weight of graphene and 60 parts by weight of 50wt% ethanol aqueous solution were mixed and placed under ultrasonic power. Ultrasonic dispersion was performed at a power of 200 W and an ultrasonic frequency of 40 kHz for 20 min, 0.5 parts by weight of (acryloyloxymethyl)phenylethyltrimethoxysilane was added, and the mixture was stirred at 50° C. and 300 rpm for 1 h, and then filtered, washed, and dried to obtain modified graphene; S3, under nitrogen environment, 3 parts by weight of the modified graphene and 0.5 parts by weight of dodecyl sulfuric acid Sodium, 3 parts by weight of eugenol antibacterial agent and 80 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.5 parts by weight of azobisisobutyl cyanide is added, and the mixture is reacted at 70°C and 400rpm for 3 hours. After the reaction is completed, the mixture is filtered, washed and dried to obtain an antibacterial composite additive.

[0042] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 300 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 120°C, discharging the material after the material temperature reaches 45°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 220°C, the die head temperature is 250°C, and the screw rotation speed is 300 rpm to obtain the antibacterial medical PVC material.

[0043] Example 3 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 100 parts by weight of PVC resin, 30 parts by weight of plasticizer, 16 parts by weight of filler, 4 parts by weight of stabilizer, 3 parts by weight of coupling agent, 2 parts by weight of lubricant, 3 parts by weight of epoxy linseed oil, 0.8 parts by weight of antioxidant 1010, and 12 parts by weight of antibacterial composite additives.

[0044] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 1.4:1.

[0045] The filler is silicon dioxide.

[0046] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 3:1.

[0047] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0048] The lubricant is stearic acid.

[0049] The preparation method of the antibacterial composite additive is as follows: S1 6 parts by weight of p-bromobenzaldehyde, 8 parts by weight of chlorhexidine and 8 parts by weight of eugenol and 120 parts by weight of 1. The mixture is mixed with 0.6 parts by weight of N,N-dimethylformamide, stirred evenly, and 0.6 parts by weight of ferric chloride is added, and stirred at 85° C. and 500 rpm for 16 hours; after the reaction is completed, the solvent is removed by distillation to obtain a eugenol antibacterial agent; S2, 8 parts by weight of graphene and 100 parts by weight of 70wt% ethanol aqueous solution were mixed and placed under ultrasonic power. Ultrasonic dispersion was performed at a power of 600 W and an ultrasonic frequency of 80 kHz for 50 min, 2 parts by weight of (acryloyloxymethyl)phenylethyltrimethoxysilane was added, and the mixture was stirred at 70° C. and 500 rpm for 3 h, and then filtered, washed, and dried to obtain modified graphene; S3, under nitrogen environment, 5 parts by weight of the modified graphene and 2 parts by weight of sodium dodecyl sulfate , 6 parts by weight of eugenol antibacterial agent and 140 parts by weight of N,N-dimethylformamide are stirred evenly, and then 1 part by weight of azobisisobutyl cyanide is added, and the mixture is reacted at 80°C and 800rpm for 6 hours. After the reaction is completed, the mixture is filtered, washed, and dried to obtain an antibacterial composite additive.

[0050] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 600 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting the material into a cooling mixer after the temperature reaches 160°C, discharging the material after the material temperature reaches 55°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 260°C, the die head temperature is 270°C, and the screw rotation speed is 600 rpm to obtain the antibacterial medical PVC material.

[0051] Comparative Example 1 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 80 parts by weight of PVC resin, 20 parts by weight of plasticizer, 10 parts by weight of filler, 3 parts by weight of stabilizer, 2 parts by weight of coupling agent, 1 part by weight of lubricant, 2 parts by weight of epoxy linseed oil, and 0.5 parts by weight of antioxidant 1010.

[0052] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 1:1.

[0053] The filler is silicon dioxide.

[0054] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 2:1.

[0055] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0056] The lubricant is stearic acid.

[0057] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent and lubricant into a high-speed mixer, adjusting the rotation speed to 500 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 140°C, discharging the material after the material temperature reaches 50°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation, and injection molding, wherein the barrel temperature of the extruder is 240°C, the die head temperature is 260°C, and the screw rotation speed is 400 rpm to obtain the antibacterial medical PVC material.

[0058] Comparative Example 2 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 80 parts by weight of PVC resin, 20 parts by weight of plasticizer, 10 parts by weight of filler, 3 parts by weight of stabilizer, 2 parts by weight of coupling agent, 1 part by weight of lubricant, 2 parts by weight of epoxy linseed oil, 0.5 parts by weight of antioxidant 1010, and 8 parts by weight of antibacterial composite additives.

[0059] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 1:1.

[0060] The filler is silicon dioxide.

[0061] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 2:1.

[0062] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0063] The lubricant is stearic acid.

[0064] The preparation method of the antibacterial composite additive is as follows: S1 4 parts by weight of p-bromobenzaldehyde, 6 parts by weight of chlorhexidine and 6 parts by weight of eugenol and 80 parts by weight of N, N-dimethylformamide was mixed and stirred evenly, 0.5 parts by weight of ferric chloride was added, and stirred at 78°C and 400 rpm for 10 hours; after the reaction was completed, the solvent was removed by distillation to obtain a eugenol antibacterial agent; S2, in a nitrogen environment, 4 parts by weight of graphene, 1 part by weight of sodium dodecyl sulfate, 5 parts by weight of 100 parts by weight of eugenol antibacterial agent and 100 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.8 parts by weight of azobisisobutyl cyanide is added, and the mixture is reacted at 75° C. and 600 rpm for 4 hours. After the reaction is completed, the mixture is filtered, washed, and dried to obtain an antibacterial composite additive.

[0065] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 500 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 140°C, discharging the material after the material temperature reaches 50°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 240°C, the die head temperature is 260°C, and the screw rotation speed is 400 rpm to obtain the antibacterial medical PVC material.

[0066] Comparative Example 3 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 80 parts by weight of PVC resin, 20 parts by weight of plasticizer, 10 parts by weight of filler, 3 parts by weight of stabilizer, 2 parts by weight of coupling agent, 1 part by weight of lubricant, 2 parts by weight of epoxy linseed oil, 0.5 parts by weight of antioxidant 1010, and 8 parts by weight of antibacterial composite additives.

[0067] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 1:1.

[0068] The filler is silicon dioxide.

[0069] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 2:1.

[0070] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0071] The lubricant is stearic acid.

[0072] The preparation method of the antibacterial composite additive is as follows: S1. Mix 6 parts by weight of graphene and 80 parts by weight of 60 wt% ethanol aqueous solution and place under ultrasonic power. Ultrasonic dispersion was performed at a power of 400 W and an ultrasonic frequency of 70 kHz for 30 min, 1 part by weight of (acryloyloxymethyl)phenylethyltrimethoxysilane was added, and the mixture was stirred at 60° C. and 400 rpm for 1.5 h, filtered, washed, and dried to obtain modified graphene; S2. In a nitrogen environment, 4 parts by weight of the modified graphene and 1 part by weight of sodium dodecyl sulfate were added. , 5 parts by weight of eugenol and 100 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.8 parts by weight of azobisisobutyl cyanide is added, and the mixture is reacted at 75° C. and 600 rpm for 4 hours. After the reaction is completed, the mixture is filtered, washed, and dried to obtain an antibacterial composite additive.

[0073] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 500 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 140°C, discharging the material after the material temperature reaches 50°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 240°C, the die head temperature is 260°C, and the screw rotation speed is 400 rpm to obtain the antibacterial medical PVC material.

[0074] Comparative Example 4 The antibacterial medical PVC material is composed of the following raw materials in parts by weight: 80 parts by weight of PVC resin, 20 parts by weight of plasticizer, 10 parts by weight of filler, 3 parts by weight of stabilizer, 2 parts by weight of coupling agent, 1 part by weight of lubricant, 2 parts by weight of epoxy linseed oil, 0.5 parts by weight of antioxidant 1010, and 8 parts by weight of antibacterial composite additives.

[0075] The plasticizer is a mixture of trioctyl citrate and methyl epoxyacetyl linolenate in a mass ratio of 1:1.

[0076] The filler is silicon dioxide.

[0077] The stabilizer is a mixture of calcium stearate and zinc laurate in a mass ratio of 2:1.

[0078] The coupling agent is diethylenetriaminopropyltrimethoxysilane.

[0079] The lubricant is stearic acid.

[0080] The preparation method of the antibacterial composite additive is as follows: S1 4 parts by weight of p-bromobenzaldehyde, 6 parts by weight of chlorhexidine and 6 parts by weight of eugenol and 80 parts by weight of N, N-dimethylformamide was mixed and stirred evenly, 0.5 parts by weight of ferric chloride was added, and stirred at 78°C and 400 rpm for 10 hours; after the reaction was completed, the solvent was removed by distillation to obtain a eugenol antibacterial agent; S2, 6 parts by weight of graphene and 80 parts by weight of 60wt% ethanol aqueous solution were mixed and placed under ultrasonic power. Ultrasonic dispersion was performed at a power of 400 W and an ultrasonic frequency of 70 kHz for 30 min, 1 part by weight of silane coupling agent KH-550 was added, and the mixture was stirred at 60° C. and 400 rpm for 1.5 h, filtered, washed, and dried to obtain modified graphene; S3, under nitrogen environment, 4 parts by weight of the modified graphene and 1 part by weight of sodium dodecyl sulfate , 5 parts by weight of eugenol antibacterial agent and 100 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.8 parts by weight of azobisisobutyl cyanide are added, and the mixture is reacted at 75°C and 600rpm for 4 hours. After the reaction is completed, the mixture is filtered, washed, and dried to obtain an antibacterial composite additive.

[0081] The preparation method of the antibacterial medical PVC material comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed to 500 rpm, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting into a cooling mixer after the temperature reaches 140°C, discharging the material after the material temperature reaches 50°C, adding the cooled material into a twin-screw extruder granulator, extruding granulation and injection molding, wherein the barrel temperature of the extruder is 240°C, the die head temperature is 260°C, and the screw rotation speed is 400 rpm to obtain the antibacterial medical PVC material.

[0082] Test Example 1 Antibacterial performance test: The national standard GB / T31402-2023 "Test method for antibacterial performance of plastic surface" was used for testing. The test method adopted the film method. Escherichia coli ATYCC 8739 and Staphylococcus aureus ATCC 6538P were used for the test. The test was repeated 5 times in parallel and the average value was taken. The results are shown in Table 1.

[0083] Table 1. Antibacterial test results of antibacterial medical PVC materials Escherichia coli inhibition rate (%) Staphylococcus aureus inhibition rate (%) Example 1 99.9% 98.9% Example 2 95.2% 94.7% Example 3 96.4% 97.3% Comparative Example 2 81.2% 78.3% Comparative Example 3 73.9% 70.4% Comparative Example 4 90.7% 90.1% Test Example 2 Tensile properties test: refer to the national standard GB / T1040.2-2022 "Determination of tensile properties of plastics Part 2: Test conditions for molded and extruded plastics" method for testing; the test specimen is a 1A dumbbell type with a thickness of 4mm and a test speed of 50mm / min. Before the test, the sample is regulated at a constant temperature of 23°C and a relative humidity of 50% for 24 hours. Five parallel groups are tested and the average value is taken. The results are shown in Table 2.

[0084] Table 2 Tensile properties test results Tensile yield stress / MPa Example 1 50.3 Comparative Example 1 37.1 Comparative Example 2 42.7 Comparative Example 3 44.4 Comparative Example 4 47.3 From the above results, it can be seen that the antibacterial medical PVC material prepared by the present invention has good antibacterial properties and mechanical properties. Comparison of Example 1 and Comparative Examples 1-3 shows that the present invention modifies graphene with a silane coupling agent containing alkenyl groups, which can improve the dispersion performance of graphene in PVC materials and improve compatibility, thereby improving the overall mechanical properties of PVC materials; on the other hand, the carbon-carbon double bonds in the alkenyl silane coupling agent introduced into graphene can effectively react with the carbon-carbon double bonds in the eugenol antibacterial agent, and the obtained antibacterial composite additive, as a whole, is added to the PVC material to more effectively improve the mechanical properties and antibacterial properties of the material, avoiding the problem of uneven dispersion in the PVC material due to the graphene suspension phenomenon, and also avoiding the problem of poor compatibility of adding graphene and antibacterial agents alone, and at the same time, it is better than adding graphene or antibacterial agents alone to the performance of PVC materials.

[0085] The reasons why the obtained antibacterial composite additive can improve the performance of PVC materials are as follows: (1) The modification of silane coupling agent improves the interfacial bonding force between graphene and PVC matrix, which helps to evenly disperse graphene in the PVC matrix and avoid agglomeration, thereby improving the uniformity and performance of the composite material. The addition of eugenol antibacterial agent may further improve this bonding by promoting further dispersion of graphene sheets and avoiding agglomeration, thereby further improving the mechanical strength of the composite material; (2) The combination of eugenol antibacterial agent and chlorhexidine provides a broad-spectrum antibacterial effect, which can effectively inhibit the growth of a variety of microorganisms and bind to the modified graphene. After combination, they can work synergistically to increase antibacterial properties, improve antibacterial efficiency and more lasting antibacterial effect. At the same time, the two can also complement each other in antibacterial mechanism. Eugenol antibacterial agent may play a role by destroying bacterial cell membrane, while modified graphene may play a role by physical adsorption and restricting bacterial activity. (3) The addition of modified graphene can improve the stress distribution in PVC materials, and eugenol antibacterial agent may enhance this effect by increasing intermolecular forces, which can increase the dispersion and stability of graphene in PVC materials, thereby increasing the filling amount of inorganic materials in the resin and improving the toughness and impact resistance of the material.

[0086] Further comparison of Example 1 and Comparative Example 4 shows that the effect of using an alkenyl silane coupling agent in the present invention is obviously better than that of not containing an alkenyl silane coupling agent. The reason is that the graphene modified without an alkenyl silane coupling agent cannot be well combined with the eugenol antibacterial agent, and cannot better play their respective complementary advantages. Therefore, the effect of using graphene modified with an alkenyl silane coupling agent will be better.

Claims

1. An antibacterial medical PVC material, characterized in that: The invention is composed of the following raw materials in parts by weight: 70-100 parts by weight of PVC resin, 10-30 parts by weight of plasticizer, 8-16 parts by weight of filler, 2-4 parts by weight of stabilizer, 1-3 parts by weight of coupling agent, 0.5-2 parts by weight of lubricant, 1-3 parts by weight of epoxy linseed oil, 0.2-0.8 parts by weight of antioxidant 1010 and 5-12 parts by weight of antibacterial composite additive.

2. The antibacterial medical PVC material according to claim 1, characterized in that: The plasticizer is one or any combination of trioctyl citrate, di(2-ethylhexyl) phthalate, butyl epoxy furoate, and methyl epoxy acetyl linoleate.

3. The antibacterial medical PVC material according to claim 1, characterized in that: The filler is one or any combination of silicon dioxide, titanium dioxide, montmorillonite and talc.

4. The antibacterial medical PVC material according to claim 1, characterized in that: The stabilizer is one or any combination of calcium stearate, zinc laurate and stearylbenzoylmethane.

5. The antibacterial medical PVC material according to claim 1, characterized in that: The coupling agent is one or any combination of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent.

6. The antibacterial medical PVC material according to claim 1, characterized in that: The lubricant is one or any combination of stearic acid, glyceryl monostearate, polypropylene wax, and polyethylene wax.

7. The antibacterial medical PVC material according to claim 1, characterized in that: The preparation method of the antibacterial composite additive is as follows: S1: mixing p-bromobenzaldehyde, chlorhexidine, eugenol and N,N-dimethylformamide, adding ferric chloride, heating and stirring to obtain eugenol antibacterial agent; S2, mixing graphene and ethanol aqueous solution and ultrasonically dispersing them, adding silane and heating them to obtain modified graphene; S3, in a nitrogen environment, the modified graphene, sodium dodecyl sulfate, cloves The phenol antibacterial agent and N,N-dimethylformamide are stirred evenly, and then azobisisobutyl cyanide is added and heated for reaction to obtain an antibacterial composite additive.

8. The antibacterial medical PVC material according to claim 7, characterized in that: The preparation method of the antibacterial composite additive is as follows: S1: 3-6 parts by weight of p-bromobenzaldehyde, 4-8 parts by weight of chlorhexidine, 4-8 parts by weight of eugenol and 70-120 parts by weight of N,N-dimethylformamide are mixed and stirred evenly, 0.1-0.6 parts by weight of ferric chloride are added, and the mixture is stirred at 75-85° C. and 300-500 rpm for 8-16 hours; after the reaction is completed, the solvent is removed by distillation to obtain a eugenol antibacterial agent; S2, 4-8 parts by weight of graphene and 60-100 parts by weight of 50-70wt% ethanol aqueous solution Mix, place under ultrasonic power of 200-600 W and ultrasonic frequency of 40-80 kHz for ultrasonic dispersion for 20-50 min, add 0.5-2 parts by weight of silane, stir at 50-70° C. and 300-500 rpm for 1-3 h, filter, wash and dry to obtain modified graphene; S3, under nitrogen environment, 3-5 weight parts of the modified graphene, 0.5-2 weight parts of 3-6 parts by weight of sodium dodecyl sulfate, 3-6 parts by weight of eugenol antibacterial agent and 80-140 parts by weight of N,N-dimethylformamide are stirred evenly, and then 0.5-1 parts by weight of azobisisobutyl cyanide are added, and the mixture is reacted at 70-80° C. and 400-800 rpm for 3-6 hours. After the reaction is completed, the mixture is filtered, washed and dried to obtain an antibacterial composite additive.

9. The antibacterial medical PVC material according to claim 7 or 8, characterized in that: The silane in S2 is a silane coupling agent containing an alkenyl group.

10. Preparation of the antibacterial medical PVC material according to any one of claims 1 to 9 The method is characterized in that The method comprises the following steps: weighing various raw materials by weight, putting PVC resin, plasticizer, filler, coupling agent, lubricant and antibacterial composite additive into a high-speed mixer, adjusting the rotation speed, adding stabilizer, epoxy linseed oil and antioxidant 1010, putting the materials into a cooling mixer after the temperature reaches 120-160°C, discharging the materials, adding the cooled materials into a twin-screw extruder granulator, extruding and granulating, and injection molding to obtain the antibacterial medical PVC material.