Bacteriostatic and mildewproof polylactic acid 3D printing wire rod and preparation method thereof

Abstract

The invention relates to the field of 3D printing materials, in particular to an antibacterial and mildew-resistant polylactic acid 3D printing wire rod and a preparation method thereof, and aims to solve the problems that an existing polylactic acid material 3D printing product is easily polluted by microorganisms such as bacteria and molds, the appearance of the product is influenced, germs are possibly transmitted, and threats are caused to human health. The 3D printing wire rod is prepared by combining the polylactic acid material with the first bacteriostatic and mildew-inhibiting agent and the second bacteriostatic and mildew-inhibiting agent which have bacteriostatic and mildew-inhibiting functions, so that the antibacterial performance of the 3D printing wire rod is remarkably enhanced, and the 3D printing wire rod has efficient and broad-spectrum bacteriostatic and mildew-inhibiting performance, shows a good inhibiting effect on various bacteria and mildew, and is suitable for being used in the field of 3D printing. The environment-friendly degradable 3D printing material effectively prevents the 3D printing material from being easily corroded and polluted by microorganisms, prolongs the service life of the 3D printing material, has the characteristics of environmental protection and degradability, is more suitable for the fields needing sanitation and environmental protection, such as medical instruments, food packaging and household appliances, and has a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the field of 3D printing materials, and in particular to an antibacterial and antifungal polylactic acid 3D printing wire and a preparation method thereof. Background Art

[0002] With the rapid development of 3D printing technology, its application areas are constantly expanding. Polylactic acid, as a biodegradable thermoplastic polyester, has become one of the most popular basic materials in the field of 3D printing due to its good mechanical properties, processing performance and environmental protection characteristics. However, in actual applications, 3D printed products made of polylactic acid materials are easily contaminated by microorganisms such as bacteria and mold. Especially in humid and warm environments, microorganisms breed and multiply rapidly, which will not only affect the appearance of the product, causing discoloration, mold, odor and other problems, but may also spread pathogens and pose a threat to human health.

[0003] Therefore, it is of great practical significance to develop an antibacterial and antifungal polylactic acid 3D printing filament and a preparation method thereof. Summary of the invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of the present invention is to provide an antibacterial and antifungal polylactic acid 3D printing wire and a preparation method thereof, which solves the problem that existing polylactic acid material 3D printed products are easily contaminated by microorganisms such as bacteria and mold, which not only affects the appearance of the products, but also may spread pathogens and pose a threat to human health.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A bacteriostatic and mildew-resistant polylactic acid 3D printing filament comprises the following components in parts by weight: 100 parts of polylactic acid resin, 1.5-3.3 parts of a first antibacterial and antifungal agent, 0.5-1.1 parts of a second antibacterial and antifungal agent, 0.5-1.5 parts of zinc stearate, 0.8-1.6 parts of ethylene bisstearamide, 0.2-0.6 parts of triglycidyl isocyanurate and 0.1-0.5 parts of 2,6-di-tert-butyl-p-cresol; Wherein, the first antibacterial and antifungal agent is prepared by the following steps: Step a1: Phenylphosphonium dichloride, imidazole, anhydrous potassium carbonate and dimethyl sulfoxide are added to a three-necked flask equipped with a stirrer, a thermometer and an air guide tube, and nitrogen is introduced for protection. The mixture is stirred for reaction at a temperature of 25-30° C. and a stirring rate of 300-400 r / min for 2-3 hours, and then the mixture is heated to 80-85° C. and stirred for reaction for 8-10 hours. After the reaction is completed, the reaction product is cooled to room temperature, and then added to distilled water, and then extracted with anhydrous ether for 2-3 times. The extracts are combined and dried over anhydrous magnesium sulfate, and then vacuum filtered, and the filtrate is rotary evaporated to remove the solvent to obtain intermediate 1; Step a2: Add intermediate 1, 3-bromo-1-propene, hydroquinone and anhydrous acetonitrile to a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube and a reflux condenser, introduce nitrogen protection, stir and react for 20-30 minutes at a temperature of 25-30° C. and a stirring rate of 300-400 r / min, then heat to reflux and continue stirring and reacting for 8-10 hours. After the reaction is completed, the reaction product is cooled to room temperature, and then the solvent is removed by rotary evaporation, and then column chromatography is performed with a mixed solvent to obtain intermediate 2; Step a3: Add intermediate 2, azobisisobutyronitrile and anhydrous tetrahydrofuran to a three-necked flask equipped with a stirrer, a thermometer and an air duct, introduce nitrogen protection, stir the reaction for 10-15 minutes at a temperature of 25-30°C and a stirring rate of 300-400r / min, then raise the temperature to 65-70°C and continue stirring the reaction for 10-15 hours. After the reaction is completed, the reaction product is cooled to room temperature, then added to ice ether and allowed to stand for precipitation, then vacuum filtered, and the filter cake is placed in a vacuum drying oven and dried at a temperature of 30-35°C for 15-20 hours to obtain a first antibacterial and antifungal agent.

[0006] As a further solution of the present invention: the usage ratio of the phenylphosphonium dichloride, imidazole, anhydrous potassium carbonate and dimethyl sulfoxide in step a1 is 10 mmol: 22-25 mmol: 30-35 mmol: 50-60 mL.

[0007] As a further scheme of the present invention: the usage ratio of the intermediate 1, 3-bromo-1-propene, hydroquinone and anhydrous acetonitrile in step a2 is 10 mmol: 33-36 mmol: 0.12-0.16 g: 50-60 mmol.

[0008] As a further solution of the present invention: the mixed solvent in step a2 is a mixture of petroleum ether and ethyl acetate in a volume ratio of 1-2:10.

[0009] As a further solution of the present invention: the usage ratio of the intermediate 2, azobisisobutyronitrile and anhydrous tetrahydrofuran in step a3 is 10 g: 0.15-0.2 g: 80-100 mL.

[0010] As a further solution of the present invention: the second antibacterial and antifungal agent is prepared by the following steps: Step b1: adding copper acetate and deionized water to a three-necked flask equipped with a stirrer and a thermometer, stirring the mixture for 10-15 minutes at a temperature of 25-30° C. and a stirring rate of 300-400 r / min, then adding glucose and continuing to stir the mixture for 10-15 minutes, then adding sodium hydroxide and continuing to stir the mixture for 10-15 minutes, then heating the mixture to 70-75° C. and continuing to stir the mixture for 2-3 hours, after which the reaction product is cooled to room temperature, centrifuged, and the precipitate is washed with anhydrous ethanol and distilled water for 3-5 times in sequence, then placed in a vacuum drying oven, and dried at a temperature of 50-55° C. for 3-5 hours to obtain cuprous oxide particles; Step b2: Add cuprous oxide particles, KH-560 silane coupling agent and ethanol solution to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, stir the reaction for 40-60 minutes at a temperature of 25-30°C and a stirring rate of 300-400r / min, then heat the temperature to reflux and continue stirring the reaction for 12-15 hours. After the reaction is completed, the reaction product is cooled to room temperature and then centrifuged. The precipitate is washed with anhydrous toluene, anhydrous ethanol and distilled water for 2-3 times in turn, and then placed in a vacuum drying oven and dried at a temperature of 50-55°C for 4-5 hours to obtain a second antibacterial and antifungal agent.

[0011] As a further solution of the present invention: the usage ratio of the copper acetate, deionized water, glucose and sodium hydroxide in step b1 is 1g:180-200mL:1.1-1.5g:1.05-1.35g.

[0012] As a further solution of the present invention: the usage ratio of the cuprous oxide particles, KH-560 silane coupling agent and ethanol solution in step b2 is 2g:2-5mL:50-60mL.

[0013] As a further solution of the present invention: the volume fraction of the ethanol solution in step b2 is 85-90%.

[0014] As a further solution of the present invention: a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire comprises the following steps: Step 1: Weigh 100 parts of polylactic acid resin, 1.5-3.3 parts of a first antibacterial and antifungal agent, 0.5-1.1 parts of a second antibacterial and antifungal agent, 0.5-1.5 parts of zinc stearate, 0.8-1.6 parts of ethylene bisstearamide, 0.2-0.6 parts of triglycidyl isocyanurate and 0.1-0.5 parts of 2,6-di-tert-butyl-p-cresol according to weight parts, and set aside; Step 2: Mix the polylactic acid resin, the first antibacterial and antifungal agent, the second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butyl-p-cresol evenly, then add them into a twin-screw extruder, melt-extrude at a temperature of 220-240°C, and then stretch and shape to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0015] As a further solution of the present invention: the polylactic acid resin is dextrorotatory PLA with model number 6201D.

[0016] Beneficial effects of the present invention: The invention discloses an antibacterial and antifungal polylactic acid 3D printing wire and a preparation method thereof. The antibacterial and antifungal polylactic acid 3D printing wire is obtained by uniformly mixing polylactic acid resin, a first antibacterial and antifungal agent, a second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butyl-p-cresol, and then melt-extruding and drawing and shaping. The antibacterial and antifungal polylactic acid 3D printing wire is obtained. The 3D printing wire is made by combining a polylactic acid material with a first antibacterial and antifungal agent and a second antibacterial and antifungal agent having antibacterial and antifungal functions, significantly enhancing the antibacterial properties of the 3D printing wire, making it have high efficiency and broad-spectrum antibacterial and antifungal properties, showing good inhibitory effects on a variety of bacteria and molds, effectively preventing the 3D printed object from being easily corroded and contaminated by microorganisms, and extending its service life. At the same time, it has the characteristics of being environmentally friendly and degradable, making it more suitable for fields requiring hygiene and environmental protection, such as medical equipment, food packaging, household appliances, etc., and has broad application prospects.

[0017] In the process of preparing antibacterial and antifungal polylactic acid 3D printing wire, a first antibacterial and antifungal agent is firstly prepared. Firstly, phenylphosphonium dichloride and imidazole are reacted, and the chlorine atom on phenylphosphonium dichloride reacts with the NH bond on imidazole to obtain intermediate 1. Then, intermediate 1 and 3-bromo-1-propylene are reacted, and the tertiary amine group and trivalent phosphorus group on intermediate 1 react with the bromine atom on bromo-1-propylene to form a quaternary ammonium group and a quaternary phosphonium group, and an olefin group is introduced to obtain intermediate 2. Then, intermediate 2 is polymerized using the olefin group thereon to form a polymer to obtain the first antibacterial and antifungal agent. The molecular structure of the first antibacterial and antifungal agent contains a large number of quaternary ammonium groups and quaternary phosphonium groups with positive charges, which can interact with the negative charges on the bacterial and fungal cell walls, destroy the integrity of the cell membrane, cause the cell substances to leak, and finally inactivate, and show good inhibitory effects on a variety of bacteria and molds. In the process of preparing the antibacterial and antifungal polylactic acid 3D printing wire, a second antibacterial and antifungal agent was also prepared. Cuprous oxide particles were prepared using copper acetate as a copper source and glucose as a reducing agent. Then, the cuprous oxide particles were treated with a KH-560 silane coupling agent. The siloxane on the KH-560 silane coupling agent was hydrolyzed to form silanols grafted to the surface of the cuprous oxide particles, and a large number of epoxy groups were introduced to obtain a second antibacterial and antifungal agent. Cuprous oxide can release copper ions, which react with the sulfhydryl and amino groups of proteins in the cell membrane to change the permeability inside and outside the cell membrane, resulting in the inactivation of bacteria and fungi. After being modified with the KH-560 silane coupling agent, its compatibility with the polylactic acid matrix was improved, ensuring the uniform distribution of the antibacterial components in the material. At the same time, the introduced epoxy groups can be connected in the form of chemical bonds, reducing the negative impact on the mechanical properties of the material and ensuring the mechanical properties of the 3D printing wire. Therefore, under the synergistic effect of the first antibacterial and antifungal agent and the second antibacterial and antifungal agent, a more effective antibacterial and antifungal effect is exerted. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Embodiment 1: This embodiment is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: 10 mmol phenylphosphine dichloride, 22 mmol imidazole, 30 mmol anhydrous potassium carbonate and 50 mL dimethyl sulfoxide are added to a three-necked flask equipped with a stirrer, a thermometer and an air guide tube, and nitrogen is introduced for protection. The mixture is stirred at 25° C. and a stirring rate of 300 r / min for 2 h, and then the mixture is heated to 80° C. and stirred for 8 h. After the reaction is completed, the reaction product is cooled to room temperature, and then added to distilled water, and then extracted twice with anhydrous ether. The extracts are combined and dried over anhydrous magnesium sulfate, and then vacuum filtered. The filtrate is rotary evaporated to remove the solvent to obtain intermediate 1; Step S2: 10 mmol of intermediate 1, 33 mmol of 3-bromo-1-propylene, 0.12 g of hydroquinone and 50 mmol of anhydrous acetonitrile were added to a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube and a reflux condenser, and nitrogen was introduced for protection. The mixture was stirred for reaction at a temperature of 25° C. and a stirring rate of 300 r / min for 20 min, and then the temperature was raised to reflux and the stirring reaction was continued for 8 h. After the reaction was completed, the reaction product was cooled to room temperature, and then the solvent was removed by rotary evaporation, and then column chromatography was performed with a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 1:10 to obtain intermediate 2; Step S3: 10 g of intermediate 2, 0.15 g of azobisisobutyronitrile and 80 mL of anhydrous tetrahydrofuran were added to a three-necked flask equipped with a stirrer, a thermometer and an air duct, and nitrogen was introduced for protection. The mixture was stirred at 25° C. and a stirring rate of 300 r / min for 10 min, and then the mixture was heated to 65° C. and the stirring reaction was continued for 10 h. After the reaction was completed, the reaction product was cooled to room temperature, and then added to ice ether and allowed to stand for precipitation, and then vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 30° C. for 15 h to obtain a first antibacterial and antifungal agent; Step S4: 1 g of copper acetate and 180 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, and the mixture was stirred for reaction at a temperature of 25° C. and a stirring rate of 300 r / min for 10 min, and then 1.1 g of glucose was added and the mixture was stirred for reaction for 10 min, and then 1.05 g of sodium hydroxide was added and the mixture was stirred for reaction for 10 min, and then the mixture was heated to 70° C. and stirred for reaction for 2 h. After the reaction, the reaction product was cooled to room temperature, and then centrifuged. The precipitate was washed three times with anhydrous ethanol and distilled water in sequence, and then placed in a vacuum drying oven and dried at a temperature of 50° C. for 3 h to obtain cuprous oxide particles; Step S5: 2 g of cuprous oxide particles, 2 mL of KH-560 silane coupling agent and 50 mL of 85% ethanol solution were added to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stirred for reaction for 40 min at a temperature of 25 ° C and a stirring rate of 300 r / min, and then the temperature was raised to reflux and the stirring reaction was continued for 12 h. After the reaction was completed, the reaction product was cooled to room temperature and then centrifuged. The precipitate was washed twice with anhydrous toluene, anhydrous ethanol and distilled water in sequence, and then placed in a vacuum drying oven and dried at a temperature of 50 ° C for 4 h to obtain a second antibacterial and antifungal agent; Step S6: 100 parts of polylactic acid resin, 1.5 parts of the first antibacterial and antifungal agent, 0.5 parts of the second antibacterial and antifungal agent, 0.5 parts of zinc stearate, 0.8 parts of ethylene bisstearamide, 0.2 parts of triglycidyl isocyanurate and 0.1 parts of 2,6-di-tert-butyl-p-cresol are weighed according to weight parts for later use; the polylactic acid resin is dextrorotatory PLA with a model of 6201D; Step S7: The polylactic acid resin, the first antibacterial and antifungal agent, the second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butylparacresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 220°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0020] Embodiment 2: This embodiment is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: 10 mmol phenylphosphine dichloride, 24 mmol imidazole, 32 mmol anhydrous potassium carbonate and 55 mL dimethyl sulfoxide were added to a three-necked flask equipped with a stirrer, a thermometer and an air guide tube, and nitrogen was introduced for protection. The mixture was stirred at 28° C. and a stirring rate of 350 r / min for 2.5 h, and then the mixture was heated to 82° C. and the stirring reaction was continued for 9 h. After the reaction was completed, the reaction product was cooled to room temperature, and then added to distilled water, and then extracted twice with anhydrous ether. The extracts were combined and dried over anhydrous magnesium sulfate, and then vacuum filtered. The filtrate was rotary evaporated to remove the solvent to obtain intermediate 1; Step S2: 10 mmol of intermediate 1, 35 mmol of 3-bromo-1-propylene, 0.14 g of hydroquinone and 55 mmol of anhydrous acetonitrile were added to a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube and a reflux condenser, and nitrogen was introduced for protection. The mixture was stirred for reaction at a temperature of 28° C. and a stirring rate of 350 r / min for 25 min, and then the temperature was raised to reflux and the stirring reaction was continued for 9 h. After the reaction was completed, the reaction product was cooled to room temperature, and then the solvent was removed by rotary evaporation. Then, column chromatography was performed with a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 1.5:10 to obtain intermediate 2; Step S3: 10 g of intermediate 2, 0.18 g of azobisisobutyronitrile and 90 mL of anhydrous tetrahydrofuran were added to a three-necked flask equipped with a stirrer, a thermometer and an air duct, and nitrogen was introduced for protection. The mixture was stirred at 28° C. and a stirring rate of 350 r / min for 12 min, and then the mixture was heated to 68° C. and the stirring reaction was continued for 12 h. After the reaction was completed, the reaction product was cooled to room temperature, and then added to ice ether and allowed to stand for precipitation, and then vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 32° C. for 18 h to obtain a first antibacterial and antifungal agent; Step S4: 1 g of copper acetate and 190 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, and the mixture was stirred for reaction at a temperature of 28° C. and a stirring rate of 350 r / min for 12 min, and then 1.3 g of glucose was added and the stirring reaction was continued for 12 min, and then 1.2 g of sodium hydroxide was added and the stirring reaction was continued for 12 min, and then the temperature was raised to 72° C. and the stirring reaction was continued for 2.5 h. After the reaction was completed, the reaction product was cooled to room temperature, and then centrifuged. The precipitate was washed with anhydrous ethanol and distilled water for 4 times in sequence, and then placed in a vacuum drying oven and dried at a temperature of 52° C. for 4 h to obtain cuprous oxide particles; Step S5: 2 g of cuprous oxide particles, 3.5 mL of KH-560 silane coupling agent and 55 mL of 88% ethanol solution were added to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stirred for reaction at a temperature of 28° C. and a stirring rate of 350 r / min for 50 min, then heated to reflux and continued to stir for 14 h. After the reaction, the reaction product was cooled to room temperature and then centrifuged. The precipitate was washed twice with anhydrous toluene, anhydrous ethanol and distilled water in sequence, and then placed in a vacuum drying oven and dried at a temperature of 52° C. for 4.5 h to obtain a second antibacterial and antifungal agent; Step S6: 100 parts of polylactic acid resin, 2.4 parts of the first antibacterial and antifungal agent, 0.8 parts of the second antibacterial and antifungal agent, 1 part of zinc stearate, 1.2 parts of ethylene bisstearamide, 0.4 parts of triglycidyl isocyanurate and 0.3 parts of 2,6-di-tert-butyl-p-cresol are weighed according to weight parts for later use; the polylactic acid resin is dextrorotatory PLA with a model of 6201D; Step S7: The polylactic acid resin, the first antibacterial and antifungal agent, the second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butylparacresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 220-240°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0021] Embodiment 3: This embodiment is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: 10 mmol phenylphosphine dichloride, 25 mmol imidazole, 35 mmol anhydrous potassium carbonate and 60 mL dimethyl sulfoxide are added to a three-necked flask equipped with a stirrer, a thermometer and an air guide tube, and nitrogen is introduced for protection. The reaction is stirred at a temperature of 30° C. and a stirring rate of 400 r / min for 3 hours, and then the temperature is raised to 85° C. and the stirring reaction is continued for 10 hours. After the reaction is completed, the reaction product is cooled to room temperature, and then added to distilled water, and then extracted with anhydrous ether for 3 times. The extracts are combined and dried over anhydrous magnesium sulfate, and then vacuum filtered, and the filtrate is rotary evaporated to remove the solvent to obtain intermediate 1; Step S2: 10 mmol of intermediate 1, 36 mmol of 3-bromo-1-propylene, 0.16 g of hydroquinone and 60 mmol of anhydrous acetonitrile were added to a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube and a reflux condenser, and nitrogen was introduced for protection. The mixture was stirred for reaction at a temperature of 30° C. and a stirring rate of 400 r / min for 30 min, and then the temperature was raised to reflux and the stirring reaction was continued for 10 h. After the reaction was completed, the reaction product was cooled to room temperature, and then the solvent was removed by rotary evaporation, and then column chromatography was performed with a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 2:10 to obtain intermediate 2; Step S3: 10 g of intermediate 2, 0.2 g of azobisisobutyronitrile and 100 mL of anhydrous tetrahydrofuran were added to a three-necked flask equipped with a stirrer, a thermometer and an air duct, and nitrogen was introduced for protection. The mixture was stirred at 30° C. and a stirring rate of 400 r / min for 15 min, and then the mixture was heated to 70° C. and the stirring reaction was continued for 15 h. After the reaction was completed, the reaction product was cooled to room temperature, and then added to ice ether and allowed to stand for precipitation, and then vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 35° C. for 20 h to obtain a first antibacterial and antifungal agent; Step S4: 1 g of copper acetate and 200 mL of deionized water were added to a three-necked flask equipped with a stirrer and a thermometer, and stirred for reaction at a temperature of 30° C. and a stirring rate of 400 r / min for 15 min, then 1.5 g of glucose was added and the stirring reaction was continued for 15 min, then 1.35 g of sodium hydroxide was added and the stirring reaction was continued for 15 min, then the temperature was raised to 75° C. and the stirring reaction was continued for 3 h, after the reaction was completed, the reaction product was cooled to room temperature, and then centrifuged, and the precipitate was washed with anhydrous ethanol and distilled water for 5 times in sequence, and then placed in a vacuum drying oven and dried at a temperature of 55° C. for 5 h to obtain cuprous oxide particles; Step S5: 2 g of cuprous oxide particles, 5 mL of KH-560 silane coupling agent and 60 mL of 90% ethanol solution by volume were added to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stirred for 60 min at a temperature of 30 ° C and a stirring rate of 400 r / min, and then heated to reflux and continued to stir for 15 h. After the reaction was completed, the reaction product was cooled to room temperature and then centrifuged. The precipitate was washed three times with anhydrous toluene, anhydrous ethanol and distilled water in sequence, and then placed in a vacuum drying oven and dried at a temperature of 55 ° C for 5 h to obtain a second antibacterial and antifungal agent; Step S6: 100 parts of polylactic acid resin, 3.3 parts of the first antibacterial and antifungal agent, 1.1 parts of the second antibacterial and antifungal agent, 1.5 parts of zinc stearate, 1.6 parts of ethylene bisstearamide, 0.6 parts of triglycidyl isocyanurate and 0.5 parts of 2,6-di-tert-butyl-p-cresol are weighed according to weight parts for later use; the polylactic acid resin is dextrorotatory PLA with a model of 6201D; Step S7: The polylactic acid resin, the first antibacterial and antifungal agent, the second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butylparacresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 240°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0022] Comparative Example 1: This comparative example is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: weigh 100 parts of polylactic acid resin, 1.5 parts of zinc stearate, 1.6 parts of ethylene bisstearamide, 0.6 parts of triglycidyl isocyanurate and 0.5 parts of 2,6-di-tert-butyl-p-cresol according to weight parts for later use; the polylactic acid resin is dextrorotatory PLA of model 6201D; Step S2: The polylactic acid resin, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butyl-p-cresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 240°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0023] Comparative Example 2: This comparative example is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: 10 mmol phenylphosphine dichloride, 25 mmol imidazole, 35 mmol anhydrous potassium carbonate and 60 mL dimethyl sulfoxide are added to a three-necked flask equipped with a stirrer, a thermometer and an air guide tube, and nitrogen is introduced for protection. The reaction is stirred at a temperature of 30° C. and a stirring rate of 400 r / min for 3 hours, and then the temperature is raised to 85° C. and the stirring reaction is continued for 10 hours. After the reaction is completed, the reaction product is cooled to room temperature, and then added to distilled water, and then extracted with anhydrous ether for 3 times. The extracts are combined and dried over anhydrous magnesium sulfate, and then vacuum filtered, and the filtrate is rotary evaporated to remove the solvent to obtain intermediate 1; Step S2: 10 mmol of intermediate 1, 36 mmol of 3-bromo-1-propylene, 0.16 g of hydroquinone and 60 mmol of anhydrous acetonitrile were added to a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube and a reflux condenser, and nitrogen was introduced for protection. The mixture was stirred for reaction at a temperature of 30° C. and a stirring rate of 400 r / min for 30 min, and then the temperature was raised to reflux and the stirring reaction was continued for 10 h. After the reaction was completed, the reaction product was cooled to room temperature, and then the solvent was removed by rotary evaporation, and then column chromatography was performed with a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 2:10 to obtain intermediate 2; Step S3: 10 g of intermediate 2, 0.2 g of azobisisobutyronitrile and 100 mL of anhydrous tetrahydrofuran were added to a three-necked flask equipped with a stirrer, a thermometer and an air duct, and nitrogen was introduced for protection. The mixture was stirred at 30° C. and a stirring rate of 400 r / min for 15 min, and then the mixture was heated to 70° C. and the stirring reaction was continued for 15 h. After the reaction was completed, the reaction product was cooled to room temperature, and then added to ice ether and allowed to stand for precipitation, and then vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 35° C. for 20 h to obtain a first antibacterial and antifungal agent; Step S4: 100 parts of polylactic acid resin, 3.3 parts of the first antibacterial and antifungal agent, 1.5 parts of zinc stearate, 1.6 parts of ethylene bisstearamide, 0.6 parts of triglycidyl isocyanurate and 0.5 parts of 2,6-di-tert-butyl-p-cresol are weighed in parts by weight for later use; the polylactic acid resin is dextrorotatory PLA of model 6201D; Step S5: The polylactic acid resin, the first antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butylparacresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 240°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0024] Comparative Example 3: This comparative example is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: 1 g of copper acetate and 200 mL of deionized water are added to a three-necked flask equipped with a stirrer and a thermometer, and stirred for reaction at a temperature of 30° C. and a stirring rate of 400 r / min for 15 min, then 1.5 g of glucose is added and the stirring reaction is continued for 15 min, then 1.35 g of sodium hydroxide is added and the stirring reaction is continued for 15 min, then the temperature is raised to 75° C. and the stirring reaction is continued for 3 h, after the reaction is completed, the reaction product is cooled to room temperature, and then centrifuged, and the precipitate is washed with anhydrous ethanol and distilled water for 5 times in sequence, and then placed in a vacuum drying oven and dried at a temperature of 55° C. for 5 h to obtain cuprous oxide particles; Step S2: 2 g of cuprous oxide particles, 5 mL of KH-560 silane coupling agent and 60 mL of 90% ethanol solution by volume were added to a three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, and stirred for 60 min at a temperature of 30 ° C and a stirring rate of 400 r / min, and then the temperature was raised to reflux and the stirring reaction was continued for 15 h. After the reaction was completed, the reaction product was cooled to room temperature and then centrifuged. The precipitate was washed three times with anhydrous toluene, anhydrous ethanol and distilled water in sequence, and then placed in a vacuum drying oven and dried at a temperature of 55 ° C for 5 h to obtain a second antibacterial and antifungal agent; Step S3: 100 parts of polylactic acid resin, 1.1 parts of the second antibacterial and antifungal agent, 1.5 parts of zinc stearate, 1.6 parts of ethylene bisstearamide, 0.6 parts of triglycidyl isocyanurate and 0.5 parts of 2,6-di-tert-butyl-p-cresol are weighed in parts by weight for later use; the polylactic acid resin is dextrorotatory PLA of model 6201D; Step S4: The polylactic acid resin, the second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butylparacresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 240°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0025] Comparative Example 4: This comparative example is a method for preparing a bacteriostatic and antifungal polylactic acid 3D printing wire, comprising the following steps: Step S1: 1 g of copper acetate and 200 mL of deionized water are added to a three-necked flask equipped with a stirrer and a thermometer, and stirred for reaction at a temperature of 30° C. and a stirring rate of 400 r / min for 15 min, then 1.5 g of glucose is added and the stirring reaction is continued for 15 min, then 1.35 g of sodium hydroxide is added and the stirring reaction is continued for 15 min, then the temperature is raised to 75° C. and the stirring reaction is continued for 3 h, after the reaction is completed, the reaction product is cooled to room temperature, and then centrifuged, and the precipitate is washed with anhydrous ethanol and distilled water for 5 times in sequence, and then placed in a vacuum drying oven and dried at a temperature of 55° C. for 5 h to obtain cuprous oxide particles; Step S2: 100 parts of polylactic acid resin, 3.3 parts of dodecyltrimethylammonium chloride, 1.1 parts of cuprous oxide particles, 1.5 parts of zinc stearate, 1.6 parts of ethylenebisstearamide, 0.6 parts of triglycidyl isocyanurate and 0.5 parts of 2,6-di-tert-butyl-p-cresol are weighed according to weight parts for later use; the polylactic acid resin is dextrorotatory PLA with a model of 6201D; Step S3: The polylactic acid resin, dodecyltrimethylammonium chloride, cuprous oxide particles, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butylparacresol are mixed evenly, then added into a twin-screw extruder, melt-extruded at a temperature of 240°C, and then stretched and shaped to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

[0026] The antibacterial and antifungal polylactic acid 3D printing filaments of Examples 1-3 and Comparative Examples 1-4 were tested for their antibacterial and antifungal properties. The test strains were Escherichia coli, Staphylococcus aureus and Aspergillus niger. The test time was 24 hours. The test results are shown in the following table:

[0027] Referring to the data in the above table, based on the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that the antibacterial and antifungal polylactic acid 3D printing filament of the present application has excellent antibacterial and antifungal properties.

[0028] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0029] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined in this application, they shall all fall within the protection scope of the present invention.

Claims

1. A bacteriostatic and antifungal polylactic acid 3D printing wire, characterized in that: It includes the following components by weight: 100 parts of polylactic acid resin, 1.5-3.3 parts of a first antibacterial and antifungal agent, 0.5-1.1 parts of a second antibacterial and antifungal agent, 0.5-1.5 parts of zinc stearate, 0.8-1.6 parts of ethylene bisstearamide, 0.2-0.6 parts of triglycidyl isocyanurate and 0.1-0.5 parts of 2,6-di-tert-butyl-p-cresol; Wherein, the first antibacterial and antifungal agent is prepared by the following steps: Step a1: stirring phenylphosphonium dichloride, imidazole, anhydrous potassium carbonate and dimethyl sulfoxide to react, cooling the reaction product after the reaction, then adding it to distilled water, then extracting, combining the extracts and drying them, then vacuum filtering, and rotary evaporating the filtrate to obtain intermediate 1; Step a2: stirring the intermediate 1, 3-bromo-1-propylene, hydroquinone and anhydrous acetonitrile to react, cooling the reaction product after the reaction is completed, then rotary evaporating, and then column chromatography with a mixed solvent to obtain the intermediate 2; Step a3: Stir the intermediate 2, azobisisobutyronitrile and anhydrous tetrahydrofuran for reaction. After the reaction is completed, cool the reaction product, add it to icy ether and let it stand to precipitate, then vacuum filter it, dry the filter cake, and obtain the first antibacterial and antifungal agent.

2. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 1, characterized in that: The usage ratio of the phenylphosphonium dichloride, imidazole, anhydrous potassium carbonate and dimethyl sulfoxide in step a1 is 10 mmol: 22-25 mmol: 30-35 mmol: 50-60 mL.

3. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 1, characterized in that: The usage ratio of the intermediate 1, 3-bromo-1-propene, hydroquinone and anhydrous acetonitrile in step a2 is 10 mmol: 33-36 mmol: 0.12-0.16 g: 50-60 mmol.

4. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 1, characterized in that: The mixed solvent in step a2 is a mixture of petroleum ether and ethyl acetate in a volume ratio of 1-2:

10.

5. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 1, characterized in that: The usage ratio of the intermediate 2, azobisisobutyronitrile and anhydrous tetrahydrofuran in step a3 is 10 g: 0.15-0.2 g: 80-100 mL.

6. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 1, characterized in that: The second antibacterial and antifungal agent is prepared by the following steps: Step b1: stirring copper acetate and deionized water for reaction, then adding glucose and sodium hydroxide and continuing stirring for reaction, cooling the reaction product after the reaction is completed, then centrifuging, washing and drying the precipitate to obtain cuprous oxide particles; Step b2: stirring the cuprous oxide particles, KH-560 silane coupling agent and ethanol solution to react, cooling the reaction product after the reaction is completed, then centrifuging, washing and drying the precipitate to obtain a second antibacterial and antifungal agent.

7. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 6, characterized in that: The usage ratio of the copper acetate, deionized water, glucose and sodium hydroxide in step b1 is 1g:180-200mL:1.1-1.5g:1.05-1.35g.

8. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 6, characterized in that: The usage ratio of the cuprous oxide particles, KH-560 silane coupling agent and ethanol solution in step b2 is 2g:2-5mL:50-60mL.

9. The antibacterial and antifungal polylactic acid 3D printing wire according to claim 6, characterized in that: The volume fraction of the ethanol solution in step b2 is 85-90%.

10. A method for preparing antibacterial and antifungal polylactic acid 3D printing wire, characterized in that: The following steps are involved: Step 1: Weigh 100 parts of polylactic acid resin, 1.5-3.3 parts of a first antibacterial and antifungal agent, 0.5-1.1 parts of a second antibacterial and antifungal agent, 0.5-1.5 parts of zinc stearate, 0.8-1.6 parts of ethylene bisstearamide, 0.2-0.6 parts of triglycidyl isocyanurate and 0.1-0.5 parts of 2,6-di-tert-butyl-p-cresol according to weight parts, and set aside; the polylactic acid resin is dextrorotatory PLA with model number 6201D; Step 2: Mix the polylactic acid resin, the first antibacterial and antifungal agent, the second antibacterial and antifungal agent, zinc stearate, ethylene bisstearamide, triglycidyl isocyanurate and 2,6-di-tert-butyl-p-cresol evenly, then add them into a twin-screw extruder, melt-extrude at a temperature of 220-240°C, and then stretch and shape to obtain an antibacterial and antifungal polylactic acid 3D printing wire with a diameter of 1.75 mm.

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