A PE material with antibacterial and scale-inhibiting properties and its preparation method

Abstract

This invention provides an antibacterial and scale-inhibiting PE material and its preparation method, belonging to the field of polymer materials technology. The preparation steps include: dissolving polyethylene in xylene, adding perfluorohexylethylene and dicumyl peroxide for reaction, precipitating, washing, and drying to obtain perfluorinated modified PE; dissolving tetra-armed polyethylene glycolamine in PBS buffer, adding 4-carboxyphenylboronic acid, EDC·HCl, and NHS, stirring in the dark, ultrafiltration, and freeze-drying to obtain PBA-PEG, dissolving it in Tris-HCl buffer, adding dopamine hydrochloride for mixing, oxidizing, dialysis purification, and drying to obtain a PBA-DA-PEG complex; premixing the perfluorinated modified PE, then mixing it with antioxidants and compatibilizers, injecting the PBA-DA-PEG complex, continuing mixing, extruding, and water-cooled pelletizing to obtain the antibacterial and scale-inhibiting PE material. The PE material obtained by this invention can simultaneously improve the antibacterial and scale-inhibiting properties of the material.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to an antibacterial and scale-inhibiting PE material and its preparation method. Background Technology

[0002] Polyethylene (PE) is non-toxic and odorless, and possesses excellent properties such as corrosion resistance, low-temperature resistance, wear resistance, impact resistance, low coefficient of friction, and food-grade hygiene. It has wide applications in various fields, being used in injection molding or extrusion molding to form pipes or as a coating on the inner walls of existing pipes. However, currently, in applications such as drainage pipes and water pipes, PE materials do not provide ideal anti-fouling performance, requiring frequent cleaning of the pipe inner walls, which is time-consuming and labor-intensive. If cleaning is not timely, excessive scale buildup can adhere tightly to the pipe walls, making cleaning extremely difficult and even causing blockages. Furthermore, while current PE materials have good chemical stability, their antibacterial properties are generally limited. In areas with high hygiene requirements, frequent sterilization and disinfection are necessary, causing inconvenience and affecting usability.

[0003] Currently, some metal antibacterial agents are added to PE materials to achieve antibacterial effects. While this can improve antibacterial performance, their dispersibility is poor, and the extrusion conditions during blending with PE cannot be well controlled, which can easily affect the overall performance of the PE material. Furthermore, it is difficult to improve the antibacterial performance of PE materials while simultaneously maintaining their scale inhibition performance, and maintaining long-term stable scale inhibition performance in PE materials is even more challenging.

[0004] For example, patent CN111609223A discloses a PE high-pressure water supply pipe and its preparation method. This PE high-pressure water supply pipe includes an antibacterial inner pipe made of antibacterial modified PE material and a protective outer pipe made of reinforced modified PE material. The antibacterial modified PE material uses zeolite as a carrier and zinc ions as a bactericide, which on the one hand strengthens the PE material, and on the other hand gives the PE material antibacterial and sterilizing effects, effectively preventing the PE pipe from accumulating a large number of bacteria during long-term operation. While the zinc metal added in this solution improves the antibacterial performance, zinc ions, as a bactericide, are prone to side reactions during melt mixing and processing. Furthermore, zinc ions on the material surface are easily detached and hydrolyzed when exposed to water, making it difficult to achieve long-lasting antibacterial performance. Moreover, this pipe material does not have a scale-inhibiting effect, and simply adding a scale inhibitor will cause more side reactions and side effects, affecting the mechanical strength of the pipe material.

[0005] Therefore, there is a need to provide a PE material with antibacterial and scale-inhibiting properties and its preparation method to solve the problems existing in the prior art. Summary of the Invention

[0006] In view of this, the present invention provides a PE material with antibacterial and scale-inhibiting properties and a method for preparing the same, which can simultaneously improve the antibacterial and scale-inhibiting properties of the material.

[0007] To achieve the above objectives, the specific solution adopted by the present invention is as follows: a method for preparing an antibacterial and scale-inhibiting PE material, comprising the following preparation steps:

[0008] S1. Dissolve polyethylene in xylene, heat and stir to dissolve, add perfluorohexylethylene and dicumyl peroxide to react, cool, pour into anhydrous methanol to precipitate, vacuum filter, wash, vacuum dry to obtain perfluoromodified PE.

[0009] S2. Dissolve the four-armed polyethylene glycolamine in PBS buffer, add 4-carboxyphenylboronic acid, EDC·HCl and NHS, stir the reaction in the dark, ultrafilter, freeze dry to obtain PBA-PEG;

[0010] S3. Dissolve the obtained PBA-PEG in Tris-HCl buffer, add dopamine hydrochloride and mix, carry out oxidation reaction, dialysis purification, freeze drying to obtain PBA-DA-PEG complex;

[0011] S4. Premix the perfluorinated modified PE, then mix the resulting premix with antioxidants and compatibilizers, inject the PBA-DA-PEG complex, continue mixing, extrude, and then granulate after water cooling to obtain antibacterial and scale-inhibiting PE material.

[0012] By modifying polyethylene with perfluorohexylethylene, the mechanical strength of the material is improved, while a fluorine atom-rich layer is formed on the PE surface, reducing the surface energy and giving the material superhydrophobic properties. This also improves the surface smoothness. When scale crystals approach, the high interfacial tension prevents the crystals from making close contact with the material, effectively reducing the deposition of scale such as calcium carbonate.

[0013] The carboxyl group of 4-carboxyphenylboronic acid (PBA-COOH) was activated by EDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride) and the catalyst NHS (N-hydroxysuccinimide), followed by reaction with tetra-arm polyethylene glycolamine (tetra-PEG-NH2) to form an amide bond, yielding PBA-PEG. Then, under alkaline conditions, dopamine (DA) was oxidized to dopaquinone, which then combined with the remaining amino group of PEG via Michael addition to form PBA-DA-PEG. Unreacted dopamine self-polymerized to form polydopamine (PDA), resulting in a PBA-DA-PEG complex containing both PBA-DA-PEG and PDA. The catechol / quinone groups in the PDA of this complex interfere with microbial membrane structure, disrupt cell membrane integrity, and enhance the antibacterial properties of the material. Furthermore, PDA adsorbs Ca2+. 2+ / Mg 2+The ions, PBA, combine with the hydroxyl groups on the scale surface, inhibiting crystal growth, reducing deposition, and giving the material scale inhibition properties, thus achieving effective antibacterial properties while also having scale inhibition properties.

[0014] Furthermore, Ca chelation via PDA in the PBA-DA-PEG complex 2+ / Mg 2+ While ions inhibit scale formation, PBA provides dynamic covalent bonds that reversibly bind with ortho-dihydroxyl groups, enabling the material surface to self-repair, thereby extending the material's service life and maintaining its scale inhibition performance. Furthermore, the adhesiveness of PDA can enhance the interfacial bonding between PEG and PE, preventing functional components from detaching, thus achieving long-lasting and stable antibacterial and scale inhibition performance.

[0015] Preferably, in step S4, POSS-MoS2 hybrid powder is premixed with perfluorinated modified PE; the POSS-MoS2 hybrid powder is prepared by the following method: adding MoS2 powder to anhydrous N-methylpyrrolidone, ultrasonicating, adding octaisobutyl-POSS, continuing ultrasonication, vacuum rotary evaporation, and then vacuum drying to obtain the product.

[0016] By adding POSS-MoS2 hybrid powder, MoS2 can improve smoothness and reduce the crystallization and adhesion of scale ions on its surface, thus improving the scaling problem. However, MoS2 has poor compatibility and dispersibility in PE, and adding too much can negatively affect the overall performance of the material. This invention hybridizes MoS2 with octaisobutyl-POSS, using the POSS cage structure embedded in the MoS2 interlayer to inhibit MoS2 stacking, improve the dispersion effect in the material, and enhance compatibility with the organic matrix. Furthermore, the siloxane cage of POSS forms physical cross-linking points with the fluorocarbon chains in perfluorinated modified PE through hydrophobic interactions, improving the bonding performance of the material. At the same time, MoS2 nanosheets can also provide rigid support, improving the strength of the material. Thus, the POSS-MoS2 hybrid powder can improve both scale inhibition performance and material strength.

[0017] Preferably, in the preparation process of the POSS-MoS2 hybrid powder, MoS2 powder with a particle size of 1-2 μm is added to anhydrous N-methylpyrrolidone and subjected to ultrasonic treatment at 600W for 2 hours. Octaisobutyl-POSS is then added, and ultrasonic treatment is continued for 1 hour. The temperature is raised to 80°C for vacuum rotary evaporation, and then vacuum dried at 60°C for 12 hours to obtain the final product.

[0018] Preferably, in step S4, after premixing the POSS-MoS2 hybrid powder with perfluorinated modified PE, the resulting premix is ​​fed into a twin-screw extruder along with antioxidant 1010 and compatibilizer PE-g-MAH. The extruder is then mixed at a temperature of 170-180°C and a screw speed of 250 rpm for 2-3 minutes. Next, the PBA-DA-PEG composite is injected through the side feed port, and the temperature is adjusted to 155-160°C and the screw speed is adjusted to 180 rpm. The mixture is then mixed for 1-2 minutes, extruded, and water-cooled and pelletized to obtain an antibacterial and scale-inhibiting PE material.

[0019] By adding each functional component one by one and mixing them, the dispersion effect is improved. Furthermore, the entire mixing process is kept at a relatively low mixing temperature, which helps to maintain the performance of each component and achieve better antibacterial and scale inhibition effects.

[0020] Preferably, in step S1, the temperature is raised to 120°C for stirring and dissolution, perfluorohexylethylene and dicumyl peroxide are added, and the reaction is carried out at 140°C for 3 hours under nitrogen protection. After cooling to room temperature, the reaction system is slowly poured into anhydrous methanol for precipitation under magnetic stirring at 300-400 rpm. The mixture is then vacuum filtered, the precipitate is washed three times with methanol, and dried under vacuum at 60°C for 12 hours to obtain perfluoromodified PE.

[0021] The above method is safer and more economical. Using methanol as a poor solvent for PE ensures complete precipitation of modified PE, reduces product loss, and has a strong ability to dissolve impurities, unreacted monomers, and initiators, thus efficiently removing impurities, while being volatile and leaving no residue.

[0022] Preferably, in step S2, the four-armed polyethylene glycolamine is dissolved in PBS buffer at pH 7.4, and 4-carboxyphenylboronic acid, EDC·HCl and NHS are added. The mixture is stirred and reacted under nitrogen protection in the dark for 24 hours, followed by ultrafiltration and freeze-drying to obtain PBA-PEG.

[0023] Preferably, in step S3, PBA-PEG is dissolved in a 10 mM Tris-HCl buffer solution with a pH of 8.5, dopamine hydrochloride is added and mixed, and air is introduced for oxidation reaction for 12 h. After dialysis purification, the molecular weight cutoff is 3.5 kDa, and the mixture is freeze-dried to obtain the PBA-DA-PEG complex.

[0024] Preferably, the antioxidant is antioxidant 1010; the compatibilizer is PE-g-MAH.

[0025] The present invention also provides a PE material for inhibiting bacteria and scale, comprising the following components in parts by weight: 80-90 parts of perfluorinated modified PE, 0.3-0.5 parts of antioxidant, 3-5 parts of compatibilizer, and 5-8 parts of PBA-DA-PEG composite.

[0026] Preferably, the PBA-DA-PEG composite comprises the following raw materials in parts by weight: 10-15 parts tetra-armed polyethylene glycolamine, 1-1.5 parts 4-carboxyphenylboronic acid, 1.5-2 parts EDC·HCl, 0.8-1 parts NHS and 3-5 parts dopamine hydrochloride.

[0027] By adopting the above proportions, the final PE material can better improve the scale inhibition and antibacterial properties of the material while maintaining the good mechanical properties of PE material. It can be used for water pipes and heat exchanger fins in high hard water environments, as well as for other material scenarios that require certain antibacterial and scale inhibition properties. It can also be used as an inner wall coating for pipes, which has great market potential.

[0028] The above-described technical solution of the present invention has at least the following beneficial effects:

[0029] 1. By modifying polyethylene with perfluorohexylethylene, the mechanical strength of the material is improved, while a fluorine atom enrichment layer is formed on the PE surface, giving the material superhydrophobic properties, improving surface smoothness, and effectively reducing the deposition of scale such as calcium carbonate.

[0030] 2. The catechol / quinone groups contained in the PDA in the PBA-DA-PEG complex interfere with the microbial membrane structure, disrupt cell membrane integrity, and enhance the antibacterial properties of the material. Furthermore, PDA adsorbs Ca... 2+ / Mg 2+ The ions, PBA, combine with the hydroxyl groups on the scale surface, inhibiting crystal growth, reducing deposition, and giving the material scale inhibition properties, thus achieving effective antibacterial properties while also having scale inhibition properties.

[0031] 3. PBA in the PBA-DA-PEG complex provides dynamic covalent bonds, which reversibly bind to the ortho-dihydroxyl group to achieve the self-healing function of the material surface, thereby extending the service life of the material and maintaining its scale inhibition performance. In addition, the adhesion of PDA can also enhance the interfacial bonding force between PEG and PE, preventing the functional components from falling off, thus achieving long-lasting and stable antibacterial and scale inhibition performance. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. The described embodiments are some embodiments of the present invention, and all other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0033] Example 1

[0034] 100g of polyethylene (PE) was dissolved in 300mL of xylene solvent, heated to 120℃ and stirred to dissolve. 15g of perfluorohexylethylene and 0.15g of dicumyl peroxide (DCP) were added, and the reaction was carried out at 140℃ for 3h under nitrogen protection. After cooling to room temperature, the reaction system was slowly poured into 800mL of anhydrous methanol under magnetic stirring at 300rpm, and a precipitate was formed. The precipitate was filtered under vacuum, washed three times with methanol to remove adsorbed impurities, and dried under vacuum at 60℃ for 12h to obtain perfluorinated modified PE particles.

[0035] 10 g of tetra-PEG-NH2 was dissolved in 500 mL of PBS buffer (pH 7.4). Then, 1 g of 4-carboxyphenylboronic acid (PBA-COOH), 1.5 g of EDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride), and 0.8 g of catalyst NHS (N-hydroxysuccinimide) were added sequentially. The mixture was stirred under nitrogen protection in the dark for 24 h. After the reaction, unreacted substances were removed by ultrafiltration, and the mixture was freeze-dried to obtain PBA-PEG. PBA-PEG was then dissolved in 500 mL of 10 mM Tris-HCl buffer (pH 8.5), and 3 g of dopamine hydrochloride (DA) was added. The mixture was then oxidized by purging with air for 12 h. When the reaction solution gradually changed from colorless to brownish-red, it was purified by dialysis, with a molecular weight cutoff of 3.5 kDa. The mixture was then freeze-dried to obtain the PBA-DA-PEG complex.

[0036] 10g of MoS2 powder with a particle size of 1-2μm was added to 500mL of anhydrous N-methylpyrrolidone (NMP) and sonicated at 600W for 2h to exfoliate into few-layer MoS2 nanosheets. 5g of octaisobutyl-POSS was added and sonicated for another 1h to make the octaisobutyl-POSS dispersed evenly and inserted into the MoS2 interlayer. The temperature was raised to 80℃ and NMP was removed by vacuum rotary evaporation. Then, the powder was vacuum dried at 60℃ for 12h to obtain POSS-MoS2 hybrid powder.

[0037] 80g of perfluorinated modified PE granules and 3g of POSS-MoS2 hybrid powder were premixed. The resulting premix was then fed into a twin-screw extruder with 0.3g of antioxidant 1010 and 3g of PE-g-MAH (maleic anhydride-grafted PE). The mixture was kneaded for 3 minutes at 170℃ and 250 rpm. Then, 5g of PBA-DA-PEG composite was injected from the side feed port. The temperature was adjusted to 155℃ and the screw speed to 180 rpm. The mixture was kneaded for 2 minutes, extruded, and then water-cooled and pelletized to obtain antibacterial and scale-inhibiting PE material granules.

[0038] Example 2

[0039] 100g of polyethylene (PE) was dissolved in 300mL of xylene solvent, heated to 120℃ and stirred to dissolve. 15g of perfluorohexylethylene and 0.15g of dicumyl peroxide (DCP) were added, and the reaction was carried out at 140℃ for 3h under nitrogen protection. After cooling to room temperature, the reaction system was slowly poured into 800mL of anhydrous methanol under magnetic stirring at 400rpm, and a precipitate was formed. The precipitate was filtered under vacuum, washed three times with methanol to remove adsorbed impurities, and dried under vacuum at 60℃ for 12h to obtain perfluorinated modified PE particles.

[0040] 15g of tetra-PEG-NH2 was dissolved in 800mL of PBS buffer (pH 7.4). 1.5g of 4-carboxyphenylboronic acid (PBA-COOH), 2g of EDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride), and 1g of catalyst NHS (N-hydroxysuccinimide) were added sequentially. The mixture was stirred under nitrogen protection in the dark for 24h. After the reaction, unreacted substances were removed by ultrafiltration, and the mixture was freeze-dried to obtain PBA-PEG. PBA-PEG was then dissolved in 600mL of 10mM Tris-HCl buffer (pH 8.5), and 5g of dopamine hydrochloride (DA) was added. An oxidation reaction was carried out by purging with air for 12h. When the reaction solution gradually changed from colorless to brownish-red, it was purified by dialysis, with a molecular weight cutoff of 3.5kDa. The mixture was then freeze-dried to obtain the PBA-DA-PEG complex.

[0041] 10g of MoS2 powder with a particle size of 1-2μm was added to 500mL of anhydrous N-methylpyrrolidone (NMP) and sonicated at 600W for 2h to exfoliate into few-layer MoS2 nanosheets. 5g of octaisobutyl-POSS was added and sonicated for another 1h to make the octaisobutyl-POSS dispersed evenly and inserted into the MoS2 interlayer. The temperature was raised to 80℃ and NMP was removed by vacuum rotary evaporation. Then, the powder was vacuum dried at 60℃ for 12h to obtain POSS-MoS2 hybrid powder.

[0042] 90g of perfluorinated modified PE granules and 5g of POSS-MoS2 hybrid powder were premixed. The resulting premix was then fed into a twin-screw extruder with 0.5g of antioxidant 1010 and 5g of PE-g-MAH (maleic anhydride-grafted PE). The mixture was kneaded for 2 minutes at 180℃ and 250 rpm. Then, 8g of PBA-DA-PEG composite was injected from the side feed port. The temperature was adjusted to 160℃ and the screw speed was adjusted to 180 rpm. The mixture was kneaded for 1 minute, extruded, and then water-cooled and pelletized to obtain antibacterial and scale-inhibiting PE material granules.

[0043] Example 3

[0044] 100g of polyethylene (PE) was dissolved in 300mL of xylene solvent, heated to 120℃ and stirred to dissolve. 15g of perfluorohexylethylene and 0.15g of dicumyl peroxide (DCP) were added, and the reaction was carried out at 140℃ for 3h under nitrogen protection. After cooling to room temperature, the reaction system was slowly poured into 800mL of anhydrous methanol under magnetic stirring at 350rpm, and a precipitate was formed. The precipitate was filtered under vacuum, washed three times with methanol to remove adsorbed impurities, and dried under vacuum at 60℃ for 12h to obtain perfluorinated modified PE particles.

[0045] 12 g of tetra-PEG-NH2 was dissolved in 600 mL of PBS buffer (pH 7.4). Then, 1.2 g of 4-carboxyphenylboronic acid (PBA-COOH), 1.6 g of EDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride), and 1 g of catalyst NHS (N-hydroxysuccinimide) were added sequentially. The mixture was stirred under nitrogen protection in the dark for 24 h. After the reaction, unreacted substances were removed by ultrafiltration, and the mixture was freeze-dried to obtain PBA-PEG. PBA-PEG was then dissolved in 550 mL of 10 mM Tris-HCl buffer (pH 8.5), and 4 g of dopamine hydrochloride (DA) was added. The mixture was then oxidized by purging with air for 12 h. When the reaction solution gradually changed from colorless to brownish-red, it was purified by dialysis, with a molecular weight cutoff of 3.5 kDa. The mixture was then freeze-dried to obtain the PBA-DA-PEG complex.

[0046] 10g of MoS2 powder with a particle size of 1-2μm was added to 500mL of anhydrous N-methylpyrrolidone (NMP) and sonicated at 600W for 2h to exfoliate into few-layer MoS2 nanosheets. 5g of octaisobutyl-POSS was added and sonicated for another 1h to make the octaisobutyl-POSS dispersed evenly and inserted into the MoS2 interlayer. The temperature was raised to 80℃ and NMP was removed by vacuum rotary evaporation. Then, the powder was vacuum dried at 60℃ for 12h to obtain POSS-MoS2 hybrid powder.

[0047] 85g of perfluorinated modified PE granules and 4g of POSS-MoS2 hybrid powder were premixed. The resulting premix was then fed into a twin-screw extruder with 0.4g of antioxidant 1010 and 4g of PE-g-MAH (maleic anhydride-grafted PE). The mixture was kneaded for 2.5 minutes at a temperature of 175℃ and a screw speed of 250 rpm. Then, 6g of PBA-DA-PEG composite was injected through the side feed port. The temperature was adjusted to 160℃ and the screw speed was adjusted to 180 rpm. The mixture was kneaded for 1.5 minutes, extruded, and then water-cooled and pelletized to obtain antibacterial and scale-inhibiting PE material granules.

[0048] Example 4

[0049] 100g of polyethylene (PE) was dissolved in 300mL of xylene solvent, heated to 120℃ and stirred to dissolve. 15g of perfluorohexylethylene and 0.15g of dicumyl peroxide (DCP) were added, and the reaction was carried out at 140℃ for 3h under nitrogen protection. After cooling to room temperature, the reaction system was slowly poured into 800mL of anhydrous methanol under magnetic stirring at 350rpm, and a precipitate was formed. The precipitate was filtered under vacuum, washed three times with methanol to remove adsorbed impurities, and dried under vacuum at 60℃ for 12h to obtain perfluorinated modified PE particles.

[0050] 10 g of tetra-PEG-NH2 was dissolved in 600 mL of PBS buffer (pH 7.4). Then, 1.0 g of 4-carboxyphenylboronic acid (PBA-COOH), 1.5 g of EDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride), and 0.8 g of catalyst NHS (N-hydroxysuccinimide) were added sequentially. The mixture was stirred under nitrogen protection in the dark for 24 h. After the reaction, unreacted substances were removed by ultrafiltration, and the mixture was freeze-dried to obtain PBA-PEG. PBA-PEG was then dissolved in 550 mL of 10 mM Tris-HCl buffer (pH 8.5), and 3 g of dopamine hydrochloride (DA) was added. The mixture was then oxidized by purging with air for 12 h. When the reaction solution gradually changed from colorless to brownish-red, it was purified by dialysis, with a molecular weight cutoff of 3.5 kDa. The mixture was then freeze-dried to obtain the PBA-DA-PEG complex.

[0051] 10g of MoS2 powder with a particle size of 1-2μm was added to 500mL of anhydrous N-methylpyrrolidone (NMP) and sonicated at 600W for 2h to exfoliate into few-layer MoS2 nanosheets. 5g of octaisobutyl-POSS was added and sonicated for another 1h to make the octaisobutyl-POSS dispersed evenly and inserted into the MoS2 interlayer. The temperature was raised to 80℃ and NMP was removed by vacuum rotary evaporation. Then, the powder was vacuum dried at 60℃ for 12h to obtain POSS-MoS2 hybrid powder.

[0052] 80g of perfluorinated modified PE granules and 3g of POSS-MoS2 hybrid powder were premixed. The resulting premix was then fed into a twin-screw extruder with 0.5g of antioxidant 1010 and 4g of PE-g-MAH (maleic anhydride-grafted PE). The mixture was kneaded for 2.5 minutes at a temperature of 175℃ and a screw speed of 250 rpm. Then, 6g of PBA-DA-PEG composite was injected through the side feed port. The temperature was adjusted to 160℃ and the screw speed was adjusted to 180 rpm. The mixture was kneaded for 1.5 minutes, extruded, and then water-cooled and pelletized to obtain antibacterial and scale-inhibiting PE material granules.

[0053] Example 5

[0054] 100g of polyethylene (PE) was dissolved in 300mL of xylene solvent, heated to 120℃ and stirred to dissolve. 15g of perfluorohexylethylene and 0.15g of dicumyl peroxide (DCP) were added, and the reaction was carried out at 140℃ for 3h under nitrogen protection. After cooling to room temperature, the reaction system was slowly poured into 800mL of anhydrous methanol under magnetic stirring at 350rpm, and a precipitate was formed. The precipitate was filtered under vacuum, washed three times with methanol to remove adsorbed impurities, and dried under vacuum at 60℃ for 12h to obtain perfluorinated modified PE particles.

[0055] 12 g of tetra-PEG-NH2 was dissolved in 600 mL of PBS buffer (pH 7.4). Then, 1.2 g of 4-carboxyphenylboronic acid (PBA-COOH), 1.6 g of EDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride), and 1 g of catalyst NHS (N-hydroxysuccinimide) were added sequentially. The mixture was stirred under nitrogen protection in the dark for 24 h. After the reaction, unreacted substances were removed by ultrafiltration, and the mixture was freeze-dried to obtain PBA-PEG. PBA-PEG was then dissolved in 550 mL of 10 mM Tris-HCl buffer (pH 8.5), and 4 g of dopamine hydrochloride (DA) was added. The mixture was then oxidized by purging with air for 12 h. When the reaction solution gradually changed from colorless to brownish-red, it was purified by dialysis, with a molecular weight cutoff of 3.5 kDa. The mixture was then freeze-dried to obtain the PBA-DA-PEG complex.

[0056] 10g of MoS2 powder with a particle size of 1-2μm was added to 500mL of anhydrous N-methylpyrrolidone (NMP) and sonicated at 600W for 2h to exfoliate into few-layer MoS2 nanosheets. 5g of octaisobutyl-POSS was added and sonicated for another 1h to make the octaisobutyl-POSS dispersed evenly and inserted into the MoS2 interlayer. The temperature was raised to 80℃ and NMP was removed by vacuum rotary evaporation. Then, the powder was vacuum dried at 60℃ for 12h to obtain POSS-MoS2 hybrid powder.

[0057] 85g of perfluorinated modified PE granules and 4g of POSS-MoS2 hybrid powder were premixed. The resulting premix was then fed into a twin-screw extruder with 0.5g of antioxidant 1010 and 4g of PE-g-MAH (maleic anhydride-grafted PE). The mixture was kneaded for 2 minutes at 175℃ and 250 rpm. Then, 6g of PBA-DA-PEG composite was injected through the side feed port. The temperature was adjusted to 160℃ and the screw speed to 180 rpm. The mixture was kneaded for 1.5 minutes, extruded, and then water-cooled and pelletized to obtain antibacterial and scale-inhibiting PE material granules.

[0058] The present invention also includes the following comparative examples and related comparative experiments.

[0059] Comparative Example 1

[0060] Compared with Example 5, the only difference is that perfluorinated modified PE was not prepared, but conventional polyethylene was used instead. All other preparation steps and materials used were the same, and antibacterial and scale-inhibiting PE material particles were finally prepared.

[0061] Comparative Example 2

[0062] Compared with Example 5, the only difference is that the PBA-DA-PEG composite was not prepared. All other preparation steps and substances used were the same, and antibacterial and scale-inhibiting PE material particles were finally prepared.

[0063] Comparative Example 3

[0064] Compared with Example 5, the only difference is that MoS2 hybrid powder was not prepared, but MoS2 powder was used instead of MoS2 hybrid powder. All other preparation steps and materials used are the same, and finally antibacterial and scale-inhibiting PE material particles are prepared.

[0065] Performance testing

[0066] (i) The PE material granules obtained in Examples 1-5 and Comparative Examples 1-3 were injection molded to form 10cm×10cm×0.2cm plates, and the following tests were performed: According to standard GB / T 31402-2023, after disinfection with ethanol and rinsing with sterile water, Escherichia coli (ATCC 8739) and Staphylococcus aureus (ATCC 6538) were inoculated respectively to perform antibacterial performance tests. The test results are summarized in Table 1 below. A JC2000D2G contact angle tester was used to perform water contact angle tests. The test results are summarized in Table 1 below. Tensile strength tests were performed according to standard GB / T 1040.2-2022. The test results are summarized in Table 1 below.

[0067] Table 1

[0068]

[0069] As can be seen from the test results in Table 1 above, the PE material particles obtained in Examples 1-5 of this invention have good antibacterial properties and ultra-high hydrophobicity, and can maintain good tensile strength. Compared with Example 5, Comparative Example 1 did not use perfluorohexylethylene to modify PE, resulting in a significant decrease in water contact angle, reduced hydrophobicity, and a significant decrease in tensile strength; Comparative Example 2 did not prepare the PBA-DA-PEG composite, resulting in poor antibacterial properties, and the material could not meet the antibacterial requirements; and Comparative Example 3 did not hybridize MoS2, resulting in a slight decrease in antibacterial effect, as well as a decrease in contact angle and tensile strength. This is mainly because the hybridized MoS2 not only improves the dispersion effect but also enhances the antibacterial effect through POSS adsorption, while also improving the strength and hydrophobicity of the material.

[0070] (II) The PE material granules obtained in Examples 1-5 and Comparative Examples 1-3 were injection molded into pipes, and the following tests were performed: Referring to standard ASTM D7463, in Ca... 2+ The calcium carbonate deposition inhibition rate was tested at a concentration of 150 mg / L (calculated as CaCO3), and the test results are summarized in Table 2 below. An accelerated scaling experiment was also conducted, under conditions of heating to 60℃ and CaCO3 concentration... 2+ Under a concentration of 150 mg / L (calculated as CaCO3), the scale inhibition performance was tested for long-term stability after 30 days of circulation. The calcium carbonate deposition inhibition rate after 30 days was tested, and the test results are summarized in Table 2 below.

[0071] Table 2

[0072]

[0073] As can be seen from the test results in Table 2 above, the PE material particles obtained in Examples 1-5 of the present invention can achieve good calcium carbonate deposition inhibition rate, all of which are greater than 84.5%, and have good scale inhibition performance. Moreover, after 30 days of heating and cycling, the deposition inhibition rate does not decrease much and can still remain above 78.2%, indicating that the antibacterial and scale-inhibiting PE material obtained by the present invention can maintain long-term stable scale inhibition performance. Compared to Example 5, Comparative Example 1 showed a slight decrease in scale inhibition rate, mainly because the PE was not modified with perfluorohexylene, resulting in reduced hydrophobicity, lower surface smoothness, and some precipitation and adsorption. However, after 30 days of heating cycling, the decrease in deposition inhibition rate was not significant. Comparative Example 2, which did not prepare the PBA-DA-PEG composite, had the worst scale inhibition performance and could not meet the scale inhibition requirements. After 30 days of heating cycling, the deposition inhibition rate decreased significantly, indicating that the PBA-DA-PEG composite played a crucial role in self-repair and maintaining stable scale inhibition performance. Comparative Example 3 also showed a slight decrease in scale inhibition performance, indicating that the POSS-MoS2 hybrid powder could better improve surface smoothness and more effectively reduce scale deposition.

[0074] The above are preferred embodiments of the present invention. For those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a PE material with antibacterial and scale-inhibiting properties, characterized in that: The preparation steps include the following: S1. Dissolve polyethylene in xylene, heat and stir to dissolve, add perfluorohexylethylene and dicumyl peroxide to react, cool, pour into anhydrous methanol to precipitate, vacuum filter, wash, vacuum dry to obtain perfluoromodified PE. S2. Dissolve the four-armed polyethylene glycolamine in PBS buffer, add 4-carboxyphenylboronic acid, EDC·HCl and NHS, stir the reaction in the dark, ultrafilter, freeze dry to obtain PBA-PEG; S3. Dissolve the obtained PBA-PEG in Tris-HCl buffer, add dopamine hydrochloride and mix, carry out oxidation reaction, dialysis purification, freeze drying to obtain PBA-DA-PEG complex; S4. POSS-MoS2 hybrid powder is premixed with perfluorinated modified PE. The resulting premix is ​​then mixed with antioxidants and compatibilizers, injected with PBA-DA-PEG composite, and mixed and extruded. After water cooling and pelletizing, antibacterial and scale-inhibiting PE material is obtained. The POSS-MoS2 hybrid powder is prepared by the following method: MoS2 powder is added to anhydrous N-methylpyrrolidone, subjected to ultrasonic treatment, octaisobutyl-POSS is added, ultrasonic treatment is continued, vacuum rotary evaporation is performed, and then vacuum drying is carried out to obtain the powder.

2. The method for preparing an antibacterial and scale-inhibiting PE material according to claim 1, characterized in that: In the preparation of the POSS-MoS2 hybrid powder, MoS2 powder with a particle size of 1-2 μm is added to anhydrous N-methylpyrrolidone and subjected to ultrasonic treatment at 600W for 2 hours. Octaisobutyl-POSS is then added, and ultrasonic treatment is continued for 1 hour. The temperature is raised to 80℃ for vacuum rotary evaporation, and then vacuum dried at 60℃ for 12 hours to obtain the final product.

3. The method for preparing an antibacterial and scale-inhibiting PE material according to claim 1, characterized in that: In step S4, the POSS-MoS2 hybrid powder is premixed with perfluorinated modified PE. The resulting premix, along with antioxidants and compatibilizers, is fed into a twin-screw extruder at a temperature of 170-180°C and a screw speed of 250 rpm for 2-3 minutes. Then, the PBA-DA-PEG composite is injected through the side feed port, the temperature is adjusted to 155-160°C, the screw speed is adjusted to 180 rpm, and the mixture is kneaded for 1-2 minutes. After extrusion and water cooling pelletizing, the antibacterial and scale-inhibiting PE material is obtained.

4. The method for preparing an antibacterial and scale-inhibiting PE material according to claim 1, characterized in that: In step S1, the temperature is raised to 120°C and stirred to dissolve the ethylene. Perfluorohexylethylene and dicumyl peroxide are added, and the reaction is carried out at 140°C for 3 hours under nitrogen protection. The mixture is then cooled to room temperature, and the reaction system is slowly poured into anhydrous methanol for precipitation under magnetic stirring at 300-400 rpm. The mixture is then vacuum filtered, and the precipitate is washed three times with methanol and dried under vacuum at 60°C for 12 hours to obtain perfluoromodified PE.

5. The method for preparing an antibacterial and scale-inhibiting PE material according to claim 1, characterized in that: In step S2, four-armed polyethylene glycolamine is dissolved in PBS buffer at pH 7.4, and 4-carboxyphenylboronic acid, EDC·HCl and NHS are added. The mixture is stirred and reacted for 24 hours under nitrogen protection in the dark, followed by ultrafiltration and freeze-drying to obtain PBA-PEG.

6. The method for preparing an antibacterial and scale-inhibiting PE material according to claim 1, characterized in that: In step S3, PBA-PEG is dissolved in a 10 mM Tris-HCl buffer solution at pH 8.5, dopamine hydrochloride is added and mixed, and air is introduced for oxidation reaction for 12 h. After dialysis purification, the molecular weight cutoff is 3.5 kDa, and the mixture is freeze-dried to obtain the PBA-DA-PEG complex.

7. The method for preparing an antibacterial and scale-inhibiting PE material according to claim 1, characterized in that: The antioxidant is antioxidant 1010; the compatibilizer is PE-g-MAH.

8. A PE material with antibacterial and scale-inhibiting properties, characterized in that: The antibacterial and scale-inhibiting PE material is prepared by the preparation method of any one of claims 1-7, comprising the following components in parts by weight: 80-90 parts of perfluorinated modified PE, 0.3-0.5 parts of antioxidant, 3-5 parts of compatibilizer, and 5-8 parts of PBA-DA-PEG composite.

9. The antibacterial and scale-inhibiting PE material according to claim 8, characterized in that: The PBA-DA-PEG composite comprises the following raw materials in parts by weight: 10-15 parts tetra-armed polyethylene glycolamine, 1-1.5 parts 4-carboxyphenylboronic acid, 1.5-2 parts EDC·HCl, 0.8-1 parts NHS and 3-5 parts dopamine hydrochloride.

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