Antibacterial polypropylene composite material, preparation method thereof and medicine bottle

Abstract

The application belongs to the technical field of high-performance polypropylene, and discloses an antibacterial polypropylene composite material, a preparation method thereof and a medicine bottle. The antibacterial polypropylene composite material is prepared from polypropylene, composite antibacterial particles, a lubricant and the like; wherein the polypropylene is 78-87.3%, the composite antibacterial particles are 10-18%, the lubricant is 1-2%, the antioxidant is 0.5%-2%, the toughening agent is 1%-3%, and the nucleating agent is 0.2%-0.3%. The antibacterial polypropylene composite material has high antibacterial performance and mechanical performance. In addition to having antibacterial effects on common bacteria such as Escherichia coli and Staphylococcus aureus, the antibacterial polypropylene composite material has significant antibacterial activity on drug-resistant bacteria such as vancomycin-resistant Enterococcus (VRE) and methicillin-resistant Staphylococcus aureus (MRSA), which shows the outstanding antibacterial characteristics of the antibacterial polypropylene composite material.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high-performance polypropylene, and more particularly relates to an antibacterial polypropylene composite material, a preparation method thereof and a medicine bottle. BACKGROUND

[0002] Polypropylene (PP) is a kind of general-purpose thermoplastic resin, which has good chemical stability and corrosion resistance, and excellent processing performance. It is widely used in packaging, automobiles, electronics, electrical appliances, medical and health fields, etc. In particular, in the medical and health field, polypropylene is often used to manufacture disposable medical devices, infusion devices, surgical supplies and pharmaceutical packaging products. However, polypropylene itself does not have antibacterial properties, and bacteria can easily grow on its surface in a humid or long-term use environment, thereby causing the risk of cross-infection, limiting its application in occasions with high requirements for health and safety. In order to improve the antibacterial properties of polypropylene materials, the existing technology usually adopts the method of adding antibacterial agents for blending modification. For example, silver ion antibacterial agents, quaternary ammonium salt antibacterial agents, etc. are widely studied and applied. However, most of these antibacterial agents are polar substances, while polypropylene itself is a non-polar polymer, and there is a large polarity difference between the two, which leads to poor dispersibility of the antibacterial agent in the matrix, poor compatibility, weak interfacial bonding force, and further affects the overall mechanical properties of the material.

[0003] At the same time, in the medical environment, drug-resistant bacterial infection has become a major challenge in the field of global public health. In particular, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) are superbugs, which have increased the difficulty of clinical treatment significantly due to their resistance to conventional antibiotics. These drug-resistant bacteria have a high detection rate in high-risk areas of hospital infection (such as intensive care units), and the mortality rate caused by infection is 2-3 times higher than that of ordinary strains.

[0004] On the other hand, in order to improve the environmental performance of polypropylene, some studies attempt to add natural wood fibers (such as wood powder) as fillers to the polypropylene matrix to reduce the cost of raw materials and enhance the biodegradability of the material. However, the addition of wood powder also brings a series of problems. First, the interfacial compatibility between wood powder and polypropylene is poor, which leads to a decrease in the mechanical properties of the composite material; second, wood powder contains a certain amount of organic components such as sugars and hemicellulose, which are prone to thermal degradation or microbial erosion during processing and use, and may become a carrier for microbial reproduction, further exacerbating the health and safety risks of the material. Therefore, how to effectively improve the antibacterial properties and comprehensive mechanical properties of polypropylene without sacrificing its original excellent performance is one of the technical problems that need to be solved in the current modification research of polypropylene materials. SUMMARY

[0005] The present application provides an antibacterial polypropylene composite material to overcome the defects of the prior art.

[0006] The present application provides a preparation method of the antibacterial polypropylene composite material.

[0007] The present application provides an antibacterial polypropylene bottle.

[0008] To solve the above technical problems, the technical scheme of the present application is as follows:

[0009] The antibacterial polypropylene composite material is prepared from polypropylene, composite antibacterial particles, lubricant, antioxidant, toughening agent, and nucleating agent; wherein the mass percentage of polypropylene is 78%-87.3%, the mass percentage of composite antibacterial particles is 10%-18%, the mass percentage of lubricant is 1%-2%, the mass percentage of antioxidant is 0.5%-2%, the mass percentage of toughening agent is 1%-3%, and the mass percentage of nucleating agent is 0.2%-0.3%.

[0010] Preferably, the polypropylene is homopolymer polypropylene.

[0011] Preferably, the melt mass flow rate of the polypropylene is 1.8-2.0 g / min, and the melt mass flow rate is determined according to GB 3682.1-2018.

[0012] Preferably, the lubricant comprises one or more of oleic acid amide, polyethylene wax, and calcium stearate.

[0013] Preferably, the antioxidant comprises one of phenolic or phosphite.

[0014] Further preferably, the antioxidant is one of antioxidant 330 (1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene), antioxidant 168 (tris(2,4-di-tert-butylphenyl) phosphite), and antioxidant 1010 tetra(3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid) pentaerythritol ester.

[0015] Preferably, the toughening agent comprises one of high-density polyethylene or low-density polyethylene.

[0016] Preferably, the nucleating agent is a sorbitol nucleating agent.

[0017] Further preferably, the nucleating agent is one of 1,3:2,4-bis(p-methylbenzylidene) sorbitol or 1,3:2,4-bis(3,4-dimethylbenzylidene)-D-sorbitol.

[0018] Further, the composite antibacterial particles are prepared by the following method:

[0019] S1 wood powder is added into acetoacetic acid modified solvent for pretreatment; then the treated wood powder is washed with ethanol aqueous solution, and dried to obtain pretreated powder.

[0020] S2 the obtained pretreated powder is added into metal ion aqueous solution, soaked, filtered to obtain a mixture.

[0021] S3 the mixture is placed in a ball mill tank for ball milling; after milling, the obtained material is washed, dried, and sieved to obtain a part with particle size of 200-300 mesh to obtain composite antibacterial particles.

[0022] Preferably, in step S1, the wood powder is selected from one or more of Chinese fir powder, pine powder, birch powder, bamboo powder and mixtures thereof.

[0023] Preferably, the wood powder is obtained by directly crushing raw wood, and the 30-60 mesh part is selected by sieving.

[0024] Preferably, the lignin content in the wood powder is not less than 25%.

[0025] Preferably, the acetoacetic acid modified solvent in step S1 is composed of acetoacetic acid ester compound and polar aprotic solvent.

[0026] Preferably, the mass ratio of acetoacetic acid ester compound to polar aprotic solvent in the acetoacetic acid modified solvent is 12-7:1, the pretreatment temperature is 100-130℃, and the pretreatment time is 4-6h.

[0027] Preferably, the mass ratio of acetoacetic acid ester compound to polar aprotic solvent in the acetoacetic acid modified solvent is 12:1.

[0028] Preferably, the acetoacetic acid ester compound comprises one or more of tert-butyl acetoacetate, ethyl acetoacetate and methyl acetoacetate.

[0029] Preferably, the acetoacetic acid ester compound is tert-butyl acetoacetate.

[0030] Preferably, the polar aprotic solvent comprises at least one of N,N-dimethylformamide and dimethyl sulfoxide.

[0031] Preferably, the polar aprotic solvent comprises N,N-dimethylformamide.

[0032] Preferably, the mass ratio of wood powder to acetoacetic acid modified solvent in step S1 is 1:10-15.

[0033] Preferably, the mass percentage of the ethanol aqueous solution in step S1 is not less than 30%.

[0034] In the present application, the wood powder is treated by using a mixed solvent containing acetoacetic acid group to realize its surface modification. This process not only increases the surface area of the wood powder and the number of active adsorption sites while retaining the natural structure of the wood powder, but also creatively improves the interfacial compatibility between the wood powder and polypropylene (PP) and increases the adsorption sites of the antibacterial component.

[0035] In the present application, the high lignin content in the wood powder can effectively enhance the interfacial interaction between the wood powder and the polypropylene matrix while maintaining its structural stability, thereby improving the compatibility of the two.

[0036] Further, the metal ion aqueous solution in step S2 contains gallium nitrate; or the solution contains gallium nitrate and zinc chloride; or the solution contains gallium nitrate and copper chloride.

[0037] Preferably, the mass percentage of gallium nitrate in the metal ion aqueous solution is 1% to 2%, the mass percentage of zinc chloride is 1% to 3%, and the mass percentage of copper chloride is 1% to 3%.

[0038] Preferably, the metal ion aqueous solution contains 2% gallium nitrate and 3% zinc chloride by mass percentage.

[0039] Preferably, the metal ion aqueous solution contains 2% gallium nitrate and 3% copper chloride by mass percentage.

[0040] Preferably, the metal ion aqueous solution contains 1% gallium nitrate and 3% zinc chloride by mass percentage.

[0041] Preferably, the metal ion aqueous solution contains 1% gallium nitrate and 3% copper chloride by mass percentage.

[0042] Preferably, the metal ion aqueous solution in step S2 is a gallium nitrate aqueous solution with a concentration of 1% to 2%.

[0043] Preferably, the soaking time in step S2 is not less than 1 hour.

[0044] Preferably, the grinding process conditions in step S3 are as follows: the grinding speed is controlled between 300 rpm and 600 rpm; and the grinding time is controlled between 30 min and 45 min.

[0045] Preferably, the flushing in step S3 uses an aqueous ethanol solution with a mass percentage of not less than 30%.

[0046] Preferably, the drying temperature in step S3 is controlled between 30 degrees Celsius and 60 degrees Celsius.

[0047] In the application, the antibacterial composite particles are prepared by mechanical chemical method, and multiple modification effects are realized through ball milling process: in the ball milling process, antibacterial active ions (such as Ga 3+ , Ga 3+ / Zn 2+ , Ga 3+ / Cu 2+ ) are mechanically and chemically affected on the acetoacetic acid sites of acetoacetic ester modified wood powder, and further form antibacterial nanoclusters; at the same time, mechanical shear force makes the cellulose microfibers on the surface of the wood powder break, and more acetoacetic acid modified sites are exposed, which significantly improves the interface performance; in addition, by controlling the ball milling parameters, the particle size of the wood powder is further refined to 200-300 meshes, and good matching with the polypropylene matrix is realized. The preparation method of the antibacterial composite particles has the functions of nanodispersion, surface activation and particle size control, and provides an effective way for preparing high-performance antibacterial composite materials.

[0048] In the application, when gallium nitrate is used alone, antibacterial effect can be achieved. When gallium metal is used in combination with zinc metal or copper ions, the antibacterial effect of zinc metal or copper ions can be significantly improved.

[0049] A preparation method of antibacterial polypropylene composite material, comprising the following steps:

[0050] The polypropylene, lubricant, composite antibacterial particles, antioxidant, toughening agent and nucleating agent are weighed according to the formula ratio, and then mixed uniformly and put into a double screw extruder for melting extrusion and granulation at 160-210 DEG C to obtain the antibacterial polypropylene composite material.

[0051] A preparation method of antibacterial polypropylene composite material, comprising the following steps:

[0052] The antibacterial polypropylene composite material is plasticized at 160-190 DEG C, and then injection molded into a blank; finally, the blank is transferred to a blow molding station for blow molding and setting after initial cooling, and the antibacterial polypropylene medicine bottle is obtained after cooling and demolding.

[0053] Preferably, the injection mold temperature is controlled at 65 DEG C.

[0054] Compared with the prior art, the technical scheme of the application has the beneficial effects that:

[0055] The application realizes the synergistic promotion of the antibacterial performance and the mechanical performance of the polypropylene composite material by introducing high-performance composite antibacterial particles into the polypropylene matrix. The antibacterial polypropylene composite material provided by the application shows significant antibacterial effect on drug-resistant strains. The antibacterial rate of the antibacterial polypropylene composite material on common Escherichia coli ATCC25922 and Staphylococcus aureus ATCC6538 is more than 98%, the antibacterial rate of the antibacterial polypropylene composite material on methicillin-resistant Staphylococcus aureus (MRSA, ATCC 43300) and vancomycin-resistant Enterococcus (VRE, ATCC 51299) is more than 97%, and the tensile performance reaches 28.1 Mpa. The excellent antibacterial performance makes the antibacterial polypropylene composite material particularly suitable for high-risk areas of hospital infection, especially medical places such as intensive care units where drug-resistant bacteria infection is prone to occur. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 Figure of antibacterial polypropylene composite material of example 1. DETAILED DESCRIPTION

[0057] The application will be further described below in combination with the drawings and specific examples, but the examples do not limit the application in any form. Unless otherwise specified, the reagents, methods and equipment used in the application are conventional reagents, methods and equipment in the technical field.

[0058] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0059] The raw materials used in the examples and comparative examples are described as follows, but are not limited to these materials:

[0060] Homopolymer polypropylene, PP PPH-T03-GD / Zhenhai Refinery, melt mass flow rate 1.9 g / min, isotacticity 97.1%.

[0061] Antioxidant 330 (1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene), 99%.

[0062] Antioxidant 168, tris(2,4-di-tert-butylphenyl) phosphite, 98%.

[0063] Antioxidant 1010, tetra(3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid) pentaerythritol ester, ≥98%.

[0064] High-density polyethylene, melting index (Melting Index): 12 g / 10 min (190℃ / 2.16 kg).

[0065] Low-density polyethylene, melting index (Melting Index): 70 g / 10 min, particle size: 600 mesh.

[0066] Nucleator 3988, 1,3:2,4-bis(3,4-dimethylbenzylidene)-D-sorbitol, 99%.

[0067] Transparent nucleator 3940, D823192 1,3:2,4-bis-p-methylbenzyl sorbitol, 98%.

[0068] Example 1

[0069] A kind of antibacterial polypropylene composite material, the specific preparation steps are as follows:

[0070] (1) preparation of antibacterial composite particles

[0071] Prepare 100 g of acetyl acetic acid modified solvent with a mass ratio of tert-butyl acetoacetate to N, N-dimethylformamide of 9:1. According to the method, 10 g of pine powder with a particle size of 30-60 mesh and a lignin content of 27% is added to 100 g of modified solvent, and treated at 120°C for 5 hours. After the reaction is completed, the reacted wood powder is washed with 70% ethanol aqueous solution and dried at 60°C to obtain the pretreated powder. The obtained pretreated powder is added to 100 g of 1% gallium nitrate aqueous solution, soaked at room temperature for 3 hours, then filtered to obtain a mixture. The mixture is placed in a ball mill tank and ground in a planetary ball mill at a speed of 500 rpm for 45 minutes. After grinding, the obtained material is washed with 70% ethanol aqueous solution, filtered and dried at 50°C. The fine powder with a particle size of 200-300 mesh is obtained by sieving, and the antibacterial composite particles are obtained.

[0072] (2) preparation of antibacterial polypropylene composite material

[0073] According to the mass ratio of 87.3% homopolymer polypropylene, 1% calcium stearate, 10% composite antibacterial particles, 0.5% antioxidant 330, 1% high-density polyethylene, and 0.2% nucleator 3940, mix uniformly, then put into a twin-screw extruder for melt blending. The temperature of each section of the extruder is adjusted as follows: zone 1 160°C, zone 2 170°C, zone 3 190°C, zone 4 200°C, zone 5 210°C, zone 6 210°C, zone 7 210°C, zone 8 200°C, zone 9 190°C, screw speed 500 r / min, screw length-diameter ratio 45:1. The material after melt blending is extruded through the extruder head and immediately enters the cooling device for cooling and shaping. Then it is stretched by the traction device and cut into granules by the cutting equipment. Finally, the antibacterial polypropylene composite material is obtained.

[0074] (3) preparation of antibacterial polypropylene bottle:

[0075] The antibacterial polypropylene composite material is plasticized at 160-190℃, then injection molded into a parison, the injection mold temperature is controlled at 65℃, and finally the parison is transferred to a blow molding station for blow molding and setting after initial cooling, and the antibacterial polypropylene medicine bottle is obtained after cooling and demolding.

[0076] Example 2

[0077] The antibacterial polypropylene composite material and the antibacterial polypropylene medicine bottle of the present embodiment are different from the preparation method of the antibacterial polypropylene composite material of Example 1 in that the mass ratio of t-butyl acetoacetate to DMF in the acetoacetate modified solvent of step (1) is 12:1.

[0078] Example 3

[0079] The antibacterial polypropylene composite material and the antibacterial polypropylene medicine bottle of the present embodiment are different from the preparation method of the antibacterial polypropylene composite material of Example 1 in that the mass ratio of t-butyl acetoacetate to DMF in the acetoacetate modified solvent of step (1) is 7:1.

[0080] Example 4

[0081] The antibacterial polypropylene composite material and the antibacterial polypropylene medicine bottle of the present embodiment are different from the preparation method of the antibacterial polypropylene composite material of Example 1 in that the preparation of the antibacterial polypropylene composite material contains 83.3% homopolypropylene, 1% polyethylene wax, 14% composite antibacterial particles, 0.5% antioxidant 330, 1% high-density polyethylene, and 0.2% nucleating agent 3940.

[0082] Example 5

[0083] The antibacterial polypropylene composite material and the antibacterial polypropylene medicine bottle of the present embodiment are different from the preparation method of the antibacterial polypropylene composite material of Example 1 in that the preparation of the antibacterial polypropylene composite material contains 78.3% homopolypropylene, 2% polyethylene wax, 18% composite antibacterial particles, 0.5% antioxidant 330, 1% high-density polyethylene, and 0.2% nucleating agent 3940.

[0084] Example 6

[0085] The antibacterial polypropylene composite material and the antibacterial polypropylene medicine bottle of the present embodiment are different from the preparation method of the antibacterial polypropylene composite material of Example 1 in that the preparation of the antibacterial polypropylene composite material contains 87.3% homopolypropylene, 1% polyethylene wax, 10% composite antibacterial particles, 0.5% antioxidant 330, 1% high-density polyethylene, and 0.2% nucleating agent 3940.

[0086] Example 7

[0087] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 is that 85.3% of the antibacterial polypropylene composite material contains 85.3% of homopolymer polypropylene, 3% of oleic acid amide, 10% of composite antibacterial particles, 0.5% of antioxidant 330, 1% of high-density polyethylene, and 0.2% of nucleating agent 3940.

[0088] Embodiment 8

[0089] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 is that in step (1), the obtained pretreated powder is added into 100 g of a mixed solution of 2% of gallium nitrate and 3% of zinc chloride, and then is soaked at room temperature for 3 hours, and then is washed with water and filtered to obtain a mixture.

[0090] Embodiment 9

[0091] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 is that in step (1), the obtained pretreated powder is added into 100 g of a mixed solution of 2% of gallium nitrate and 3% of copper chloride, and then is soaked at room temperature for 3 hours, and then is washed with water and filtered to obtain a mixture.

[0092] Embodiment 10

[0093] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 is that in step (1), the obtained pretreated powder is added into 100 g of a mixed solution of 1% of gallium nitrate and 3% of copper chloride, and then is soaked at room temperature for 3 hours, and then is washed with water and filtered to obtain a mixture.

[0094] Embodiment 11

[0095] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 is that in step (1), the obtained pretreated powder is added into 100 g of a mixed solution of 1% of gallium nitrate and 3% of copper chloride, and then is soaked at room temperature for 3 hours, and then is washed with water and filtered to obtain a mixture.

[0096] Embodiment 12

[0097] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that in step (1), the non-polar protic solvent in the acetoacetic acid modification solvent is dimethyl sulfoxide; and the planetary ball mill is ground at a rotating speed of 500 rpm, and the grinding time is 30 minutes.

[0098] Embodiment 13

[0099] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that in step (2), according to the mass weighing ratio of 83.7% homopolymer polypropylene, 1% calcium stearate, 10% composite antibacterial particles, 2% antioxidant 168, 3% low-density polyethylene and 0.3% nucleating agent 3988, the mixture is uniformly put into a double-screw extruder for melt blending.

[0100] Embodiment 14

[0101] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that in step (2), according to the mass weighing ratio of 83.7% homopolymer polypropylene, 1% calcium stearate, 10% composite antibacterial particles, 2% antioxidant 168, 3% low-density polyethylene and 0.3% nucleating agent 3988, the mixture is uniformly put into a double-screw extruder for melt blending.

[0102] Comparative example 1

[0103] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that in step (2), the preparation of the antibacterial polypropylene composite material does not add wood powder.

[0104] Comparative example 2

[0105] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that in step (2), the preparation of the antibacterial polypropylene composite material adds 10% natural wood powder with a mesh size of 200-300.

[0106] Comparative example 3

[0107] The embodiment provides an antibacterial polypropylene composite material and an antibacterial polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that in step (1), the composite antibacterial particles are not subjected to acetoacetic acid pretreatment.

[0108] Comparative example 4

[0109] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and example 1 is that in step (1), no gallium nitrate is added, the obtained pretreated powder is added into 100 g of a zinc chloride aqueous solution with a mass percentage of 3%, soaked for 3 hours at normal temperature, then washed with water and filtered to obtain a mixture.

[0110] Comparative example 5

[0111] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and example 1 is that in step (1), no gallium nitrate is added, the obtained pretreated powder is added into 100 g of a zinc chloride aqueous solution with a mass percentage of 3%, soaked for 3 hours at normal temperature, then washed with water and filtered to obtain a mixture.

[0112] Comparative example 6

[0113] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and example 1 is that in step (1), the obtained pretreated powder is added into 100 g of a zinc chloride aqueous solution with a mass percentage of 3% and 0.01% gallium nitrate, soaked for 3 hours at normal temperature, then washed with water and filtered to obtain a mixture.

[0114] Comparative example 7

[0115] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and example 1 is that in step (1), the obtained pretreated powder is added into 100 g of a zinc chloride aqueous solution with a mass percentage of 3% and 3% gallium nitrate, soaked for 3 hours at normal temperature, then washed with water and filtered to obtain a mixture.

[0116] Comparative example 8

[0117] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and example 1 is that in step (1), the antibacterial particles less than 200 mesh are screened.

[0118] Comparative example 9

[0119] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and example 1 is that in step (1), the antibacterial particles greater than 300 mesh are screened.

[0120] Comparative example 10

[0121] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that no lubricant is added in step (2).

[0122] Comparative example 11

[0123] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that no lubricant is added in step (2).

[0124] Comparative example 12

[0125] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that no lubricant is added in step (2).

[0126] Comparative example 13

[0127] The embodiment provides an antibacterial polypropylene composite material and a polypropylene medicine bottle, and the difference between the specific preparation method of the antibacterial polypropylene composite material and embodiment 1 lies in that no lubricant is added in step (2).

[0128] Detection method:

[0129] The lignin determination method refers to GB / T 2677.8-1994 Determination of Acid Insoluble Lignin Content in Papermaking Raw Materials. The obtained antibacterial polypropylene material is pressed into a standard required size plastic sheet; the tensile property test refers to GB / T 1040.2-2006; the antibacterial property is evaluated according to the ISO 22196:2011 standard method, and the antibacterial effect on Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 6538), methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300, and vancomycin-resistant Enterococcus VRE, ATCC 51299 is evaluated.

[0130] The results are shown in the following table:

[0131] Table 1 Detection results of antibacterial polypropylene material

[0132]

[0133] Result explanation

[0134] As can be seen from the data in Table 1, the results of Examples 1 to 14 show that the present application, by introducing the composite antibacterial particles into the polypropylene matrix and using a specific type of lubricant, makes the resulting material not only exhibit excellent antibacterial properties against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 6538), but also has good antibacterial effect against drug-resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA, ATCC 43300) and vancomycin-resistant Enterococcus faecalis (VRE, ATCC 51922), with antibacterial percentage exceeding 97%. In addition, the composite antibacterial particles not only impart antibacterial properties to the material, but also have a synergistic effect of enhancing the tensile properties of the polypropylene matrix. The tests show that the mechanical properties such as tensile strength of the material are significantly improved, reaching more than 28 MPa.

[0135] According to the comparative analysis of the test results of Example 1 and Comparative Examples 1-2, it can be seen that the polypropylene material without adding the composite antibacterial particles of the present application in Comparative Example 1 and the polypropylene material with un-antibacterial modified wood powder in Comparative Example 2 have an antibacterial rate of 10.1%-15%; although the wood powder content in Comparative Example 2 is the same as that in Example 1 (10 wt%), its tensile strength is lower than that in Example 1 due to the lack of antibacterial functionalization. In contrast, the antibacterial composite polypropylene material of the present application exhibits excellent comprehensive performance, with an antibacterial rate of more than 97% and excellent mechanical properties, with a tensile strength that is 15.6% higher than that in Comparative Example 1 and 11.1% higher than that in Comparative Example 2. This comparison result fully proves that the present application, by introducing the composite antibacterial particles, not only imparts antibacterial function to the material, but also improves the mechanical properties of the material.

[0136] According to the test results of Examples 1-3, it can be seen that the concentration of tert-butyl acetoacetate in the pretreatment process is positively correlated with the antibacterial properties of the final product. When the mass ratio of tert-butyl acetoacetate to DMF is in the range of 7:1 to 12:1, the antibacterial rate of the product against Escherichia coli and Staphylococcus aureus is 99%, and the antibacterial rate against drug-resistant bacteria is 98%. In the preparation method of the composite antibacterial particles of the present application, the acetoacetate surface modification treatment plays an important role in improving the antibacterial effect. The test data of Comparative Example 3 shows that the corresponding antibacterial performance of the sample without acetoacetate surface modification is significantly reduced, with an antibacterial rate of only 23.3%-40.3%.

[0137] As can be seen from Example 1, Examples 8-11 and Comparative Examples 4-7, the use of specific gallium ions (Ga3+) as the antibacterial component in the aqueous metal salt solution plays an important role in achieving the comprehensive performance of the material. As can be seen from Comparative Examples 4-5, when only conventional zinc ions (Zn2+) or copper ions (Cu2+) are used instead, the antibacterial rate of the product against common Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 decreases to 91.5-94.1%, and the antibacterial effect against drug-resistant strains (MRSA and VRE) is significantly less than 50%. As can be seen from Comparative Examples 6-7, the gallium ion concentration in the range of 1-2% is optimal for the performance of the material: a concentration lower than 1% leads to a decrease in antibacterial performance, with the antibacterial rate of the product against common Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 being 92.8-94.1%, and the antibacterial rate against drug-resistant strains (MRSA and VRE) being less than 50%, and a concentration higher than 2% leads to a decrease in mechanical performance to 23.5 MPa.

[0138] As can be seen from Example 1 and Comparative Examples 8-9, the particle size range of the composite antibacterial particles has an effect on the performance of the polypropylene composite material. When composite antibacterial particles of 200-300 mesh are used, the material exhibits the optimal combination of comprehensive performance: the tensile strength reaches 28.1 MPa, and the antibacterial rate is maintained at more than 97%. Comparative Examples 8-9 show that when the particle size of the particles exceeds the optimal range, the performance of the material decreases significantly: in Comparative Example 8, composite antibacterial particles of less than 200 mesh result in a 27.1% decrease in tensile strength and a decrease in antibacterial performance to 90.6-93.1%; and in Comparative Example 9, composite antibacterial particles of more than 300 mesh result in a 20% decrease in tensile strength and a decrease in antibacterial performance against drug-resistant bacteria to 95.3-96.1%, which is worse than the range of 200-300 mesh. These data fully demonstrate that controlling the particle size of the composite antibacterial particles in the range of 200-300 mesh is an important technical feature for achieving the best balance between antibacterial performance and mechanical performance.

[0139] As can be seen from Example 1, Examples 6-7 and Comparative Example 10, the use of a lubricant in the present application results in a significant decrease in the mechanical performance of the material to only 21.1 MPa, indicating that the lubricant in the present application plays an important role in improving the interfacial compatibility of the composite material.

[0140] According to the test data of Example 1, Examples 4-5 and Comparative Examples 11-12, it is shown that the content of the composite antibacterial particles in the polypropylene matrix has a significant correlation with the material performance: when the content of the composite antibacterial particles is controlled in the range of 10-18wt%, the antibacterial performance of the material is significantly improved with the increase of the content of the antibacterial particles. In Comparative Example 11, when the content of the composite antibacterial particles is less than 10wt%, the antibacterial performance of the material is obviously decreased, and the antibacterial rate is less than 95%; in Comparative Example 12, when the content of the composite antibacterial particles is more than 18wt%, although the antibacterial rate is maintained above 98%, the mechanical performance of the material is decreased compared with Example 1, and the tensile strength is decreased by about 15.7%.

[0141] As can be seen from Example 1 and Comparative Example 13, the content of lignin in the raw material of the present application has an influence on the performance of the product, and the antibacterial performance and the mechanical performance of the product using the wood powder with the content of lignin less than 23% are both decreased, the tensile performance is decreased by about 17.8%, and the antibacterial rate is decreased to 87.1%-92.1%.

[0142] The above examples are only examples for clearly illustrating the present application, and are not intended to limit the embodiments of the present application. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. It is not necessary or possible to exhaust all the embodiments. Any modification, equivalent replacement and improvement within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. An antibacterial polypropylene composite material, characterized by, Prepared from polypropylene, composite antibacterial particles, lubricant, antioxidant, toughening agent, nucleating agent; wherein the mass percentage of polypropylene is 78%-87.3%, the mass percentage of composite antibacterial particles is 10%-18%, the mass percentage of lubricant is 1%-2%, the mass percentage of antioxidant is 0.5%-2%, the mass percentage of toughening agent is 1%-3%, and the mass percentage of nucleating agent is 0.2%-0.3%. The composite antibacterial particles are prepared by the following method: S1: wood powder is added to an acetoacetic acid modified solvent for pretreatment; then the treated wood powder is washed with an ethanol aqueous solution, and then dried to obtain pretreated powder; S2: the pretreated powder is added to a metal ion aqueous solution, soaked, filtered, and a mixture is obtained; S3: the mixture is placed in a ball mill tank for ball milling; after milling, the obtained material is rinsed, dried, and sieved to obtain a portion with a particle size of 200-300 mesh to obtain composite antibacterial particles; The acetoacetic acid modified solvent is composed of acetoacetic acid ester compounds and polar aprotic solvents; The polar aprotic solvent comprises at least one of N,N-dimethylformamide and dimethyl sulfoxide; The lignin content in the wood powder is not less than 25%; The metal ion aqueous solution contains gallium nitrate; or the metal ion aqueous solution contains gallium nitrate and zinc chloride; or the metal ion aqueous solution contains gallium nitrate and copper chloride; The mass percentage of gallium nitrate in the metal ion aqueous solution is 1%-2%. The acetoacetic acid ester compounds comprise one or more of tert-butyl acetoacetate, ethyl acetoacetate, and methyl acetoacetate.

2. The antibacterial polypropylene composite material according to claim 1, characterized in that, The mass ratio of the acetoacetic acid ester compounds to the polar aprotic solvent in step S1 is 12-7:

1.

3. The antibacterial polypropylene composite material according to claim 1, characterized in that, The mass percentage of gallium nitrate in the metal ion aqueous solution is 1%-2%, the mass percentage of zinc chloride is 1%-3%, and the mass percentage of copper chloride is 1%-3%.

4. The antibacterial polypropylene composite of claim 1, wherein The mass ratio of the wood powder to the acetoacetic acid modified solvent in step S1 is 1:10-15.

5. A process for the preparation of the antibacterial polypropylene composite material according to any one of claims 1 to 4, characterized in that, The method comprises the following steps: Polypropylene, lubricant, composite antibacterial particles, antioxidant, toughening agent, and nucleating agent are weighed according to the formula ratio; the weighed polypropylene, lubricant, antioxidant, toughening agent, nucleating agent, and composite antibacterial particles are uniformly mixed and then fed into a double-screw extruder for melt extrusion and granulation at 160-210°C to obtain an antibacterial polypropylene composite material.

6. An antibacterial polypropylene vial, characterized by, The method comprises the following steps: The antibacterial polypropylene composite material of any one of claims 1-4 is plasticated at 160-190°C, and then a parison is injection molded; finally, the parison is transferred to a blow molding station for blow molding and setting after initial cooling, and an antibacterial polypropylene medicine bottle is obtained after cooling and demolding.

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