Antibacterial nylon material and preparation method thereof

Abstract

The invention belongs to the technical field of material modification, and particularly relates to an antibacterial nylon material and a preparation method thereof. The invention relates to an antibacterial nylon material. The antibacterial nylon material is prepared from the following raw materials in parts by weight: 1 to 20 parts of organic coated zirconium phosphate silver-loaded powder and 80 to 99 parts of polyamide resin, wherein the organically coated zirconium phosphate silver-loaded powder comprises a zirconium phosphate silver-loaded material and a polymer protection layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protection layer is formed by polymerizing an LCST polymer monomer and an acrylic monomer on the particle surface of the zirconium phosphate silver-loaded material; the polymer protection layer is used for regulating and controlling the release rate of silver ions when the environment humidity changes.

Description

Technical Field

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

[0002] Nylon (also known as polyamide) is a material with advantages such as high strength, wear resistance, chemical stability, and easy processing and molding. It is widely used in many fields such as textiles, electronics, automobiles, aviation, and medical devices, becoming a major material in modern industrial production and daily consumer goods. From a mechanical performance perspective, nylon not only has excellent tensile strength and impact toughness, but also has good self-lubricating properties and fatigue resistance, and can withstand wear and impact in various environments. In addition, the diverse modification methods of nylon provide ample room for improvement in flame retardancy, toughening, and weather resistance, thus maintaining its important position in the ranks of engineering plastics.

[0003] Although nylon has outstanding mechanical and chemical properties, it lacks antibacterial properties and is particularly prone to the growth of bacteria and fungi in environments with high relative humidity. The attachment and reproduction of microorganisms on and inside the material can not only cause discoloration, mold, odor, and performance degradation, but can also endanger its safety, especially in fields such as medical care and food packaging that have strict requirements on cleanliness and hygiene. Therefore, to meet the application needs of these special environments, researchers have tried to introduce a variety of antibacterial components into the nylon matrix, such as metal ions and inorganic carriers, to extend the service life of the material and ensure hygiene and safety by reducing microbial attachment.

[0004] In existing research and industrial practice, antimicrobial modification often faces a series of challenges: First, it is difficult to balance the uniformity of dispersion and adhesion of antimicrobial agents in the material matrix. If not properly formulated, they will agglomerate or become rapidly inactivated due to excessive contact with active substances in the environment. Second, during the high-temperature extrusion process, antimicrobial components may undergo thermal decomposition or denaturation, failing to fully retain their active ingredients. Third, different antimicrobial agents have different bactericidal spectra and bactericidal efficiencies against microorganisms such as bacteria and fungi, making it difficult to balance durability and broad-spectrum properties. Based on this, how to fully utilize the excellent comprehensive properties of nylon and, based on this, effectively improve antimicrobial durability and inhibit microbial reproduction has always been a key research direction of materials science and industry. Summary of the Invention

[0005] The purpose of the present invention is to solve the above-mentioned shortcomings and provide an antibacterial nylon material and a preparation method thereof.

[0006] In the first aspect, an antibacterial nylon material adopts the following technical solution:

[0007] An antibacterial nylon material, the raw materials of which include components by weight: 1 to 20 parts by weight of organically coated zirconium phosphate silver-loaded powder and 80 to 99 parts by weight of polyamide resin;

[0008] The organically coated zirconium phosphate silver-loaded powder comprises a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material. The polymer protective layer is formed by polymerizing LCST polymer monomers and acrylic acid monomers on the particle surface of the zirconium phosphate silver-loaded material. The polymer protective layer is used to regulate the release rate of silver ions when the ambient humidity changes.

[0009] Furthermore, the molar ratio of the LCST polymer monomer to the acrylic acid monomer is (1-5):1.

[0010] Furthermore, the LCST polymer monomer is selected from one or more of N-isopropylacrylamide, N-vinylcaprolactam, N,N′-diethylacrylamide, N-acryloylpyrrolidine, N-acryloylpiperidine, and N-acryloylmorpholine.

[0011] Furthermore, the average particle size of the zirconium phosphate silver-loaded powder is ≤15 μm.

[0012] Furthermore, the silver content of the zirconium phosphate silver-supported powder is 0.4 wt% to 4.0 wt%.

[0013] In the second aspect, a method for preparing an antibacterial nylon material adopts the following technical solution:

[0014] A method for preparing an antibacterial nylon material comprises the following steps: mixing and granulating organically coated zirconium phosphate silver-loaded powder and polyamide resin to obtain the antibacterial nylon material.

[0015] Furthermore, the preparation method of the organically coated zirconium phosphate silver-loaded powder comprises the following steps:

[0016] The zirconium phosphate-supported silver material is added to a mixed solution including an LCST polymer monomer, an acrylic monomer, an initiator, and a solvent, and an inert gas is introduced to remove oxygen while maintaining an inert atmosphere. The temperature is raised to 70° C. to 80° C. and the reaction is carried out for 2 h to 4 h. A cross-linking agent is added dropwise, and the reaction is continued for 1 h to 3 h. The solid-liquid separation is performed and the mixture is dried to obtain the organic-coated zirconium phosphate-supported silver powder.

[0017] Furthermore, the initiator is selected from one of ammonium persulfate, benzoyl peroxide, azobisisobutyronitrile, azobisisoheptanenitrile, and 4,4'-azobis(4-cyanovaleric acid);

[0018] The crosslinking agent is selected from one of N,N′-methylenebisacrylamide, ethylene glycol dimethacrylate, divinylbenzene, 1,6-hexanediol diacrylate, and pentaerythritol triacrylate;

[0019] The solvent is selected from one of ethanol, N,N-dimethylformamide, tetrahydrofuran, tetrafluoroethanol and dimethyl sulfoxide.

[0020] Furthermore, the method also includes a pretreatment process of the zirconium phosphate silver-loaded material: mixing the zirconium phosphate silver-loaded material with a buffer solution, performing ultrasonic treatment, filtering, washing, and drying; wherein the mass ratio of the zirconium phosphate silver-loaded material to the buffer solution is 1:(80-120).

[0021] Furthermore, the buffer is selected from one of HEPES buffer, MOPS buffer, Tricine buffer and Tris buffer.

[0022] Beneficial effects of the present invention:

[0023] The antibacterial nylon material provided by the present invention significantly improves the antibacterial performance, antibacterial durability and humidity responsiveness of the material by compounding organically coated zirconium phosphate silver-loaded powder with polyamide resin. Zirconium phosphate, as a stable inorganic carrier, can effectively load silver ions and improve their thermal stability, inhibiting the decomposition or agglomeration of silver ions during high-temperature melt processing, ensuring the stable presence of the antibacterial agent in the material system. The polymer protective layer introduced on the surface of the silver-loaded powder is formed by in-situ polymerization of LCST polymer monomers and acrylic monomers. This protective layer can undergo a hydrophilic and hydrophobic transition under changes in humidity or temperature, giving the antibacterial agent a certain "smart release" property: it maintains slow release in normal temperature and humidity or relatively dry environments, thereby extending the antibacterial effectiveness period; in high humidity environments, the polymer chain segments stretch and the hydrophilicity is enhanced, accelerating the release of silver ions, improving the antibacterial efficiency, and effectively addressing high-risk scenarios for microbial breeding. Compared with the traditional method of directly doping silver salts or silver powder, the coating structure adopted by the present invention effectively reduces the direct contact of silver ions with oxygen or moisture in the air, inhibits the oxidative deactivation process, and improves the service life and sanitary reliability of the material. In addition, the good compatibility and dispersibility of the coated antibacterial powder with polyamide resin significantly improves the processing uniformity and physical properties of the material, avoids the migration or sedimentation of the antibacterial agent in the matrix, and ensures that the antibacterial properties of the material are stable during its service life. DETAILED DESCRIPTION

[0024] The following examples further describe the antibacterial nylon material and its preparation method described in the present invention. For the sake of simplicity, this document cannot list all the alternative technical features and implementation plans contained in the present invention. Therefore, those skilled in the art should know that any technical features and implementation plans in this embodiment do not limit the scope of protection of the present invention. The scope of protection includes any alternative technical features and implementation plans adopted by all those skilled in the art without creative work. Specifically, the implementation plans obtained by replacing any technical feature in the present invention or combining any two or more technical features provided by the present invention should be within the scope of protection of the present invention.

[0025] If the specific techniques and conditions are not specified in the examples, the procedures were carried out according to the techniques and conditions described in the literature in the field or according to the product instructions. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0026] Example

[0027] Example 1

[0028] Example 1 provides an antibacterial nylon material, the raw materials of which include 1 kg of organic-coated zirconium phosphate silver-loaded powder and 99 kg of polyamide PA6 resin; the organic-coated zirconium phosphate silver-loaded powder includes a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protective layer is formed by polymerizing N-isopropylacrylamide monomer and acrylic acid monomer on the surface of particles of the zirconium phosphate silver-loaded material.

[0029] The particle size of the silver-loaded zirconium phosphate material is 7.8 μm, and the silver-loaded content is 2.5 wt %.

[0030] Example 1 also provides a method for preparing an antibacterial nylon material, comprising the following steps:

[0031] Organically coated zirconium phosphate silver-loaded powder and polyamide PA6 resin are mixed and granulated by a screw, and the heating temperatures of the six zones of the main machine are set to 180°C, 195°C, 200°C, 215°C, 225°C, and 225°C to obtain antibacterial nylon material.

[0032] Example 1 also provides a method for preparing organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0033] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution. The ultrasonic treatment time is 1.0 h, the weight ratio of the powder to the buffer solution is 1:105, and the buffer solution is HEPES (pH = 7.4). After the vibration is completed, the powder is filtered, washed, and dried.

[0034] Step (2), the mixed solution is prepared and shaken evenly, then poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 128 mL of N-isopropylacrylamide monomer, 37 mL of acrylic acid, 0.82 mL of azobisisobutyronitrile and 450 mL of ethanol solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-supported powder is added to a three-necked flask, and the oil bath temperature is raised to 75°C. After the reaction for 2.5 hours, 80 μL of N,N′-methylenebisacrylamide is added dropwise to the solution by hanging drop, and the entire solution system is kept in a turbid state. After the addition is completed, the reaction is continued for 3 hours while stirring under the protection of inert gas, and the precipitate is collected by centrifugation, washed several times with ethanol, and dried at 80°C to obtain an organically coated zirconium phosphate silver-supported powder.

[0035] Example 2

[0036] Example 2 provides an antibacterial nylon material, the raw materials of which include 10 kg of organic-coated zirconium phosphate silver-loaded powder and 90 kg of polyamide PA9 resin; the organic-coated zirconium phosphate silver-loaded powder includes a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protective layer is formed by polymerizing N,N′-diethylacrylamide and acrylic acid monomers on the surface of particles of the zirconium phosphate silver-loaded material.

[0037] The particle size of the silver-loaded zirconium phosphate material is 5.2 μm, and the silver-loaded content is 3.0 wt %.

[0038] Example 2 also provides a preparation method of an antibacterial nylon material, which is the same as that of Example 1.

[0039] Example 2 also provides a method for preparing organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0040] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution, wherein the ultrasonic treatment time is 1.0 h, the weight ratio of the powder to the buffer solution is 1:100, and the buffer solution is Tris buffer solution (pH = 8.0). After the vibration is completed, the powder is filtered, washed, and dried.

[0041] Step (2), the prepared mixed solution is shaken evenly and poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 180 mL N, N′-diethyl-2-acrylamide, 60 mL acrylic acid, 1.10 mL azobisisobutyronitrile and 500 mL ethanol solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-loaded powder is added to the three-necked flask, and the oil bath temperature is raised to 75° C. After the reaction for 3 hours, 116 μL N, N′-methylenebisacrylamide is added dropwise to the solution by hanging drop, and the entire solution system is kept in a turbid state. After the addition is completed, the reaction is continued for 2 hours while stirring under the protection of inert gas, and the precipitate is collected by centrifugation, washed with ethanol several times, and then dried at 80° C. to obtain an organically coated zirconium phosphate silver-loaded powder.

[0042] Example 3

[0043] Example 3 provides an antibacterial nylon material, the raw materials of which include 5 kg of organic-coated zirconium phosphate silver-loaded powder and 95 kg of polyamide PA66 resin; the organic-coated zirconium phosphate silver-loaded powder includes a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protective layer is formed by polymerization of N-vinylcaprolactam and acrylic acid monomers on the particle surface of the zirconium phosphate silver-loaded material.

[0044] The particle size of the silver-loaded zirconium phosphate material is 3.6 μm, and the silver-loaded content is 1.8 wt %.

[0045] Example 3 also provides a preparation method of an antibacterial nylon material, which is the same as that of Example 1.

[0046] Example 3 also provides a method for preparing organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0047] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution. The ultrasonic treatment time is 0.5 h, the weight ratio of the powder to the buffer solution is 1:85, and the buffer solution is MOPS buffer solution (pH = 7.2). After the vibration is completed, the powder is filtered, washed, and dried.

[0048] Step (2), the prepared mixed solution is shaken evenly and poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 90 mL of N-vinylcaprolactam, 45 mL of acrylic acid, 0.75 mL of azobisisobutyronitrile and 400 mL of tetrahydrofuran solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-loaded powder is added to a three-necked flask, and the oil bath temperature is raised to 70°C. After the reaction for 2 hours, 80 μL of ethylene glycol dimethacrylate is added dropwise to the solution by hanging drop, and the entire solution system is kept in a turbid state. After the addition is completed, the reaction is continued for 1 hour while stirring under the protection of an inert gas, and the precipitate is collected by centrifugation, washed several times with ethanol, and dried at 80°C to obtain an organically coated zirconium phosphate silver-loaded powder.

[0049] Example 4

[0050] Example 4 provides an antibacterial nylon material, the raw materials of which include 20 kg of organic-coated zirconium phosphate silver-loaded powder and 80 kg of polyamide PA6 resin; the organic-coated zirconium phosphate silver-loaded powder includes a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protective layer is formed by polymerization of N-acryloylmorpholine and acrylic acid monomers on the particle surface of the zirconium phosphate silver-loaded material.

[0051] The particle size of the silver-loaded zirconium phosphate material is 12.1 μm, and the silver-loaded content is 0.60 wt %.

[0052] Example 4 also provides a preparation method of an antibacterial nylon material, which is the same as that of Example 1.

[0053] Example 4 also provides a method for preparing organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0054] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution for 1 h, with a weight ratio of powder to buffer solution of 1:90, and the buffer solution being Tricine (pH = 8.1). After the vibration is completed, the powder is filtered, washed, and dried.

[0055] Step (2), the prepared mixed solution is shaken evenly and poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 110mL N-acryloylmorpholine, 35mL acrylic acid, 0.9mL azobisisoheptanenitrile and 420mL ethanol solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-loaded powder is added to the three-necked flask, and the oil bath temperature is raised to 70°C. After the reaction for 3 hours, 80μL divinylbenzene is added dropwise to the solution by hanging drop, and the entire solution system is kept in a turbid state. After the addition is completed, the reaction is continued for 1.5 hours while stirring under the protection of inert gas, and the precipitate is collected by centrifugation, washed several times with ethanol, and dried at 80°C to obtain an organically coated zirconium phosphate silver-loaded powder.

[0056] Example 5

[0057] Example 5 provides an antibacterial nylon material, the raw materials of which include 15 kg of organic-coated zirconium phosphate silver-loaded powder and 85 kg of polyamide PA6 resin; the organic-coated zirconium phosphate silver-loaded powder includes a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protective layer is formed by polymerization of N-acryloylpyrrolidine and acrylic acid monomers on the particle surface of the zirconium phosphate silver-loaded material.

[0058] The particle size of the silver-loaded zirconium phosphate material is 8 μm, and the silver-loaded content is 4.0 wt %.

[0059] Example 5 also provides a preparation method of an antibacterial nylon material, which is the same as that of Example 1.

[0060] Example 5 also provides a method for preparing organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0061] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution. The ultrasonic treatment time is 0.5 h, the weight ratio of the powder to the buffer solution is 1:120, and the buffer solution is HEPES buffer solution (pH = 7.6). After the vibration is completed, the powder is filtered, washed, and dried.

[0062] Step (2), the prepared mixed solution is shaken evenly and then poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 100 mL of N-acryloylpyrrolidine, 20 mL of acrylic acid, 0.6 mL of azobisisobutyronitrile and 300 mL of tetrafluoroethanol solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-loaded powder is added to a three-necked flask, and the oil bath temperature is raised to 75°C. After the reaction for 2 hours, 80 μL of N, N′-methylenebisacrylamide is added dropwise to the solution by hanging drop, and the entire solution system is kept turbid. After the addition is completed, the reaction is continued for 1.5 hours while stirring under the protection of inert gas, and the precipitate is collected by centrifugation, washed several times with ethanol, and dried at 80°C to obtain an organically coated zirconium phosphate silver-loaded powder.

[0063] Example 6

[0064] Example 6 provides an antibacterial nylon material, the raw materials of which include 2 kg of organic-coated zirconium phosphate silver-loaded powder and 98 kg of polyamide PA6 resin; the organic-coated zirconium phosphate silver-loaded powder includes a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material, and the polymer protective layer is formed by polymerization of N-acryloylpiperidine and acrylic acid monomer on the particle surface of the zirconium phosphate silver-loaded material.

[0065] The particle size of the silver-loaded zirconium phosphate material is 14.5 μm, and the silver-loaded content is 0.4 wt %.

[0066] Example 6 also provides a preparation method of an antibacterial nylon material, which is the same as that of Example 1.

[0067] Example 6 also provides a method for preparing organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0068] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution. The ultrasonic treatment time is 1 hour, the weight ratio of the powder to the buffer solution is 1:110, and the buffer solution is Tris-acetate buffer (pH = 7.8). After the vibration is completed, the powder is filtered, washed, and dried.

[0069] Step (2), the prepared mixed solution is shaken evenly and poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 60 mL of N-acryloylpiperidine, 30 mL of acrylic acid, 0.7 mL of azobisisobutyronitrile and 350 mL of tetrahydrofuran solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-loaded powder is added to the three-necked flask, and the oil bath temperature is raised to 75°C. After the reaction for 2.5 hours, 80 μL of N, N′-methylenebisacrylamide is added dropwise to the solution by hanging drop, and the entire solution system is kept in a turbid state. After the addition is completed, the reaction is continued for 2 hours while stirring under the protection of inert gas, and the precipitate is collected by centrifugation, washed several times with ethanol, and dried at 80°C to obtain an organically coated zirconium phosphate silver-loaded powder.

[0070] Comparative Example

[0071] Comparative Example 1

[0072] The difference between the antibacterial nylon material provided in Comparative Example 1 and Example 5 is that the organic-coated zirconium phosphate silver-loaded powder is replaced by an equal amount of zirconium phosphate silver-loaded material.

[0073] Comparative Example 2

[0074] The antibacterial nylon material provided in Comparative Example 2 differs from that in Example 5 in that the polymer protective layer is formed solely by polymerization of acrylic acid. Specifically, Comparative Example 2 provides an antibacterial nylon material whose raw materials include 15 kg of organically coated zirconium phosphate silver-loaded powder and 85 kg of polyamide PA6 resin. The organically coated zirconium phosphate silver-loaded powder includes the zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material. The polymer protective layer is formed by polymerization of acrylic acid monomers on the surface of the zirconium phosphate silver-loaded particles.

[0075] The particle size of the silver-loaded zirconium phosphate material is 0.8 μm, and the silver-loaded content is 4.0 wt %.

[0076] Comparative Example 2 also provides a preparation method of an antibacterial nylon material that is the same as that of Example 5.

[0077] Comparative Example 2 also provides a method for preparing an organically coated zirconium phosphate silver-loaded powder, comprising the following steps:

[0078] Step (1): ultrasonically vibrate the zirconium phosphate silver-loaded material powder using a buffer solution. The ultrasonic treatment time is 0.5 h, the weight ratio of the powder to the buffer solution is 1:120, and the buffer solution is HEPES buffer solution (pH = 7.6). After the vibration is completed, the powder is filtered, washed, and dried.

[0079] Step (2), the prepared mixed solution is shaken evenly and poured into a flask, and nitrogen is introduced for 45 minutes while stirring to remove oxygen in the solution; the mixed solution includes 20 mL of acrylic acid, 0.6 mL of azobisisobutyronitrile and 400 mL of tetrafluoroethanol solvent, and nitrogen is introduced. The pre-treated zirconium phosphate silver-loaded powder is added to a three-necked flask, and the oil bath temperature is raised to 75°C. After the reaction for 2 hours, 80 μL of N, N′-methylenebisacrylamide is added dropwise to the solution by hanging drop, and the entire solution system is kept in a turbid state. After the addition is completed, the reaction is continued for 1.5 hours while stirring under the protection of inert gas, and the precipitate is collected by centrifugation, washed several times with ethanol, and dried at 80°C to obtain an organically coated zirconium phosphate silver-loaded powder.

[0080] Comparative Example 3

[0081] Comparative Example 3 provides an antibacterial nylon material, which differs from Example 5 in that the average particle size of the organically coated zirconium phosphate silver-loaded powder is 15.8 μm.

[0082] The preparation method of an antibacterial nylon material and the preparation method of an organic-coated zirconium phosphate silver-loaded powder provided in Comparative Example 3 are the same as those in Example 5.

[0083] Comparative Example 4

[0084] Comparative Example 4 provides an antibacterial nylon material, which differs from Example 5 in that the average particle size of the organically coated zirconium phosphate silver-loaded powder is 17.2 μm.

[0085] The preparation method of an antibacterial nylon material and the preparation method of an organic-coated zirconium phosphate silver-loaded powder provided in Comparative Example 4 are the same as those in Example 5.

[0086] Comparative Example 5

[0087] Comparative Example 5 provides an antibacterial nylon material and its preparation method is the same as that of Example 5.

[0088] The preparation method of the organic-coated zirconium phosphate silver-supported powder provided in Comparative Example 5 is different from that in Example 5 in that 40 mL of N-acryloylpyrrolidine and 20 mL of acrylic acid are added for polymerization.

[0089] Comparative Example 6

[0090] Comparative Example 6 provides an antibacterial nylon material and its preparation method is the same as that of Example 5.

[0091] The method for preparing the organically coated zirconium phosphate silver-supported powder provided in Comparative Example 6 differs from that in Example 5 in that the cross-linking agent N,N′-methylenebisacrylamide is not added dropwise to continue the reaction.

[0092] Performance Testing

[0093] The antibacterial nylon materials obtained in Examples 1 to 6 and Comparative Examples 1 to 6 were made into 20*200 mm injection molded strips. The strips were treated in an environment of temperature 85°C / humidity RH=85% for 5000 hours and then transferred to a natural environment of 25°C / RH=65% for 72 hours. The antibacterial properties were evaluated using the plate count method with reference to the standard GB / T 31402-2015. Detailed parameters are shown in Table 1.

[0094] Table 1 Antibacterial performance test results

[0095]

[0096] The above experimental results indicate that the finer the particle size of the zirconium phosphate powder, the more likely it is to reduce the effectiveness of the surface treatment due to agglomeration during the organic synthesis reaction. During the high-temperature, high-humidity treatment, the release rate of silver ions is not effectively regulated, and the antibacterial effect is not fully controlled. Consequently, the antibacterial rates of the materials treated with high-temperature, high-humidity treatment against all three bacterial species are generally low. During the organic coating of the zirconium phosphate-loaded silver powder, no acrylamide-containing crosslinker was added to the solution system, resulting in a relatively low antibacterial rate after high-temperature, high-humidity treatment. On the other hand, the introduction of a crosslinker not only increases the heat resistance of the overall organic layer but also improves the compatibility of the powder with the plastic matrix, reducing agglomeration and enhancing dispersibility. The better the dispersibility, the more pronounced and uniform the antibacterial effect after high-temperature, high-humidity treatment. In summary, the introduction of an organic coating prevents direct silver ion exposure to air when the antibacterial agent is mixed with the plastic, improving the dispersion of the powder within the resin and enabling a slow release of the antibacterial agent, thus prolonging the antibacterial effect. Even in a high temperature and high humidity environment, the release rate of silver ions can be adjusted accordingly according to the changes in environmental temperature and humidity, avoiding the effective antibacterial ingredients from overflowing too quickly, resulting in performance waste and failure.

[0097] It is obvious to those skilled in the art that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here, and obvious variations or modifications derived therefrom are still within the scope of protection of the claims of the present invention.

Claims

1. An antibacterial nylon material, characterized in that: The raw materials of the antibacterial nylon material include components by weight: 1 to 20 parts by weight of organically coated zirconium phosphate silver-loaded powder and 80 to 99 parts by weight of polyamide resin; The organically coated zirconium phosphate silver-loaded powder comprises a zirconium phosphate silver-loaded material and a polymer protective layer coated on the surface of the zirconium phosphate silver-loaded material. The polymer protective layer is formed by polymerizing LCST polymer monomers and acrylic acid monomers on the particle surface of the zirconium phosphate silver-loaded material. The polymer protective layer is used to regulate the release rate of silver ions when the ambient humidity changes.

2. The antibacterial nylon material according to claim 1, characterized in that: The molar ratio of the LCST polymer monomer to the acrylic acid monomer is (1-5):

1.

3. The antibacterial nylon material according to claim 1, characterized in that: The LCST polymer monomer is selected from one or more of N-isopropylacrylamide, N-vinylcaprolactam, N,N′-diethylacrylamide, N-acryloylpyrrolidine, N-acryloylpiperidine, and N-acryloylmorpholine.

4. The antibacterial nylon material according to claim 1, characterized in that: The average particle size of the zirconium phosphate silver-supported powder is ≤15 μm.

5. The antibacterial nylon material according to claim 1, characterized in that: The silver content of the zirconium phosphate silver-supported powder is 0.4 wt % to 4.0 wt %.

6. A method for preparing an antibacterial nylon material, characterized in that: The antibacterial nylon material is obtained by mixing and granulating organically coated zirconium phosphate silver-loaded powder and polyamide resin.

7. The method for preparing an antibacterial nylon material according to claim 6, characterized in that: The preparation method of the organic-coated zirconium phosphate silver-loaded powder comprises the following steps: The zirconium phosphate-supported silver material is added to a mixed solution including an LCST polymer monomer, an acrylic monomer, an initiator, and a solvent, and an inert gas is introduced to remove oxygen while maintaining an inert atmosphere. The temperature is raised to 70° C. to 80° C. and the reaction is carried out for 2 h to 4 h. A cross-linking agent is added dropwise, and the reaction is continued for 1 h to 3 h. The solid-liquid separation is performed and the mixture is dried to obtain the organic-coated zirconium phosphate-supported silver powder.

8. The method for preparing an antibacterial nylon material according to claim 7, characterized in that: The initiator is selected from one of ammonium persulfate, benzoyl peroxide, azobisisobutyronitrile, azobisisoheptanenitrile, and 4,4'-azobis(4-cyanovaleric acid); The crosslinking agent is selected from one of N,N′-methylenebisacrylamide, ethylene glycol dimethacrylate, divinylbenzene, 1,6-hexanediol diacrylate, and pentaerythritol triacrylate; The solvent is selected from one of ethanol, N,N-dimethylformamide, tetrahydrofuran, tetrafluoroethanol and dimethyl sulfoxide.

9. The method for preparing an antibacterial nylon material according to claim 7, characterized in that: The method also includes a pretreatment process of the zirconium phosphate silver-loaded material: mixing the zirconium phosphate silver-loaded material with a buffer solution, performing ultrasonic treatment, filtering, washing, and drying; wherein the mass ratio of the zirconium phosphate silver-loaded material to the buffer solution is 1:(80-120).

10. The method for preparing an antibacterial nylon material according to claim 9, characterized in that: The buffer is selected from one of HEPES buffer, MOPS buffer, Tricine buffer and Tris buffer.

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