Preparation method of antibacterial high-temperature-resistant PE plastic product
By reacting end-hydroxybutadiene with maleic anhydride and triazine diamine, then complexing with azole, the method enhances the thermal stability and antibacterial properties of superhigh molecular weight PE, resulting in a high-temperature resistant and antibacterial PE product with improved mechanical strength and uniform additive distribution.
Patent Information
- Application Number
- CN202510586555.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-08
- Publication Date
- 2025-07-15
AI Technical Summary
In the prior art, when improving the heat resistance and antibacterial properties of ultra-high molecular weight polyethylene, conventional methods will cause their strength or elongation to break to deteriorate.
The metathesis reaction is carried out by end-hydroxyl polybutadiene, maleic anhydride, sulfoxide chloride, triazine diamine compounds and propylene metronidazole and other materials to prepare heat-resistant and antibacterial additives, blended with ultra-high molecular weight polyethylene and granulated by melt extrusion to form antibacterial and high-temperature PE plastic products.
The prepared antibacterial and high-temperature PE plastic products have good mechanical properties, heat-resistant flame retardant properties and antibacterial properties. The oxygen index can reach up to 32.6 and the antibacterial rate can reach up to 99.9%, avoiding the problem of uneven dispersion of additives in plastics.
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Figure CN120310105A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a preparation method of an antibacterial and high-temperature resistant PE plastic product, belonging to the technical field of polymer materials. Background Art
[0002] Ultra-high molecular weight polyethylene refers to polyethylene with a molecular weight of more than 1 million, and its molecular structure is exactly the same as that of ordinary polyethylene. The ultra-high molecular weight endows it with excellent mechanical and mechanical properties. Therefore, ultra-high molecular weight polyethylene can be used as a thermoplastic engineering plastic. Ultra-high molecular weight polyethylene has good wear resistance, impact resistance, low temperature resistance, stress cracking resistance, corrosion resistance, light resistance, anti-adhesion, as well as electrical insulation, self-lubrication, etc., and can replace materials such as carbon steel, stainless steel, and bronze. Therefore, it is widely used in textile, mining, chemical industry, packaging, machinery, medical, sports and other fields.
[0003] Although ultra-high molecular weight polyethylene has many advantages, its processing is difficult, and its heat resistance and antibacterial properties are poor. The use temperature is lower than 85 °C, and it is easy to breed bacteria, which greatly limits its use effect and application range. In order to improve its heat resistance and antibacterial properties, the current conventional method is to add solid fillers or organic small molecule additives. However, while improving the heat resistance and antibacterial properties of ultra-high molecular weight polyethylene, this method often causes the strength or elongation at break of ultra-high molecular weight polyethylene to deteriorate. Summary of the Invention
[0004] The purpose of the present invention is to provide a preparation method of an antibacterial and high-temperature resistant PE plastic product to solve the problem that when using solid fillers or organic small molecule additives to improve the heat resistance and antibacterial properties of ultra-high molecular weight polyethylene, the strength or elongation at break of ultra-high molecular weight polyethylene will deteriorate.
[0005] The present invention provides a preparation method of an antibacterial and high-temperature resistant PE plastic product, including the following steps: (1) Reacting hydroxyl-terminated polybutadiene with maleic anhydride to obtain carboxyl-terminated polybutadiene, and the molar ratio of the hydroxyl group in the hydroxyl-terminated polybutadiene to the maleic anhydride is 1:1; the hydroxyl value of the hydroxyl-terminated polybutadiene is 0.47 - 0.73 mmol / g, and the number average molecular weight is 2800 - 4500; (2) Reacting the carboxyl-terminated polybutadiene with thionyl chloride to obtain acyl chloride-terminated polybutadiene; (3) Reacting the acyl chloride-terminated polybutadiene with a triazine diamine compound to obtain triazine-blocked polybutadiene, and the molar ratio of the acyl chloride group in the acyl chloride-terminated polybutadiene to the amino group in the triazine diamine compound is 1:1; the structure of the triazine diamine compound is shown in Formula I or Formula II: ; (4) Perform olefin metathesis reaction on triazine-block polybutadiene and propylene metronidazole to obtain a heat-resistant antibacterial additive, and the mass ratio of triazine-block polybutadiene to propylene metronidazole is 1:5 to 8; the structure of propylene metronidazole is as follows: ; (5) Perform melt extrusion granulation on the heat-resistant antibacterial additive and ultra-high molecular weight polyethylene with a mass ratio of 6 to 8:100 to obtain polyethylene particles; then perform compression molding on the polyethylene particles to obtain an antibacterial and high-temperature resistant PE plastic product.
[0006] Preferably, the preparation method of the triazine diamine compound is as follows: React cyanuric chloride with a heterocyclic amine compound and pyrazine-2,3-diyldimethylamine in sequence to obtain a triazine diamine compound; the heterocyclic amine compound is 1-methyl-2-imidazolemethanamine or 2-pyrimidine methanamine; the molar ratio of cyanuric chloride, the heterocyclic amine compound, and pyrazine-2,3-diyldimethylamine is 1:1:2.1 to 2.3.
[0007] Preferably, the temperature for the reaction of cyanuric chloride and the heterocyclic amine compound is 0 to 5 °C, and the time is 3 to 4 h; the temperature for the reaction of cyanuric chloride and pyrazine-2,3-diyldimethylamine is 105 to 115 °C, and the time is 8 to 10 h.
[0008] Preferably, the temperature for the reaction of hydroxyl-terminated polybutadiene and maleic anhydride is 70 to 80 °C, and the time is 5 to 7 h.
[0009] Preferably, the mass ratio of carboxyl-terminated polybutadiene to thionyl chloride is 1:7 to 9.
[0010] Preferably, the temperature for the reaction of acyl chloride-terminated polybutadiene and the triazine diamine compound is 0 to 5 °C, and the time is 5 to 8 h.
[0011] Preferably, the temperature for the olefin metathesis reaction is 50 to 60 °C, the time is 1 to 1.5 h, and the catalyst during the reaction is (1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxybenzylidene)ruthenium, and the mass is 0.5 to 0.8% of the mass of triazine-block polybutadiene.
[0012] Preferably, the hydroxyl value of the hydroxyl-terminated polybutadiene is 0.55 to 0.68 mmol / g, and the number average molecular weight is 3000 to 3700.
[0013] Preferably, the temperature for the melt extrusion granulation is 205 to 215 °C.
[0014] Preferably, the heating temperature for the compression molding is 220 to 230 °C, the time is 0.8 to 1.2 h, and the pressure is 8 to 10 MPa.
[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The antibacterial and high-temperature resistant PE plastic product of the present invention is prepared by blending and melt-extruding a heat-resistant antibacterial additive and ultra-high molecular weight polyethylene, and has good mechanical and mechanical properties, heat-resistant flame-retardant properties and antibacterial properties. The oxygen index can reach up to 32.6 at most, and the antibacterial rate can reach up to 99.9% at most. Among them, the heat-resistant antibacterial additive contains a triazine chain segment, a pyrazine chain segment, a heterocyclic amine side chain and a metronidazole side chain, and each group chain segment has a synergistic cooperation effect to ensure that the PE plastic product has good heat-resistant flame-retardant properties and antibacterial properties. After the polybutadiene chain segment in the heat-resistant antibacterial additive undergoes an olefin metathesis reaction with propylene metronidazole, the double bond in the polybutadiene chain segment becomes a carbon-carbon single bond, forming a carbon-carbon single bond structure identical to that of polypropylene, improving the affinity between the heat-resistant antibacterial additive and ultra-high molecular weight polyethylene, and avoiding uneven dispersion of the heat-resistant antibacterial additive in the PE plastic product, which affects the improvement of heat-resistant flame-retardant properties and antibacterial properties. Description of the Drawings
[0016] Figure 1 1H NMR spectrum of the triazine diamine compound prepared in Example 1. Detailed Embodiments
[0017] The following examples are intended to further illustrate the content of the present invention rather than limit the protection scope of the present invention.
[0018] Specific examples of the preparation method of the antibacterial and high-temperature resistant PE plastic product of the present invention are as follows: Example 1
[0019] The preparation method of the antibacterial and high-temperature resistant PE plastic product of this example includes the following steps: (1) Add cyanuric chloride and ether to the first reaction kettle, stir until cyanuric chloride is fully dissolved to obtain a 15% cyanuric chloride solution by mass fraction; add 1-methyl-2-imidazolemethanamine, triethylamine and ether to the second reaction kettle, stir evenly to obtain a first mixed solution, and the mass fraction of 1-methyl-2-imidazolemethanamine in the first mixed solution is 20%; adjust the temperature of the material in the first reaction kettle to 0 °C, and then dropwise add the first mixed solution to the first reaction kettle under stirring conditions. After the dropping is completed, continue to stir the material in the first reaction kettle for 3 h; among them, the molar ratio of cyanuric chloride, 1-methyl-2-imidazolemethanamine and triethylamine is 1:1:1.1; Pyrazine-2,3-diyldimethanamine, triethylamine, and diethyl ether were added to the third reaction kettle and stirred evenly to obtain a second mixed solution. The mass fraction of pyrazine-2,3-diyldimethanamine in the second mixed solution was 15%. The temperature of the material in the first reaction kettle was adjusted to room temperature, and then the second mixed solution was added dropwise to the first reaction kettle under stirring conditions. After the addition was completed, the material in the first reaction kettle was heated to 105 °C, and stirring reaction was continued for 8 h. Then it was cooled to room temperature, and diethyl ether was removed by vacuum distillation to obtain a concentrate. Then the concentrate was purified by column chromatography. The eluent used for purification was composed of methanol, ethyl acetate, and petroleum ether with a volume ratio of 1:2:3. After the purification was completed, the eluent collected by purification was subjected to vacuum distillation to remove the solvent, and a triazine diamine compound was obtained (the nuclear magnetic resonance hydrogen spectrum of the triazine diamine compound is as shown in Figure 1 ). Among them, the molar ratio of pyrazine-2,3-diyldimethanamine to cyanuric chloride was 2.1:1, the molar ratio of pyrazine-2,3-diyldimethanamine to triethylamine was 1:2.2, and the structure of the triazine diamine compound was as follows: .
[0020] (2) Hydroxyl-terminated polybutadiene was heated under vacuum to remove water, and then added to the reaction kettle. Then maleic anhydride and anhydrous dichloromethane were added to the reaction kettle, and it was heated to 70 °C and stirred and refluxed for 5 h. Dichloromethane was removed by vacuum distillation to obtain carboxyl-terminated polybutadiene. Among them, the hydroxyl value of the hydroxyl-terminated polybutadiene was 0.55 mmol / g, the number-average molecular weight was 3700, the molar ratio of the hydroxyl group in the hydroxyl-terminated polybutadiene to the molar amount of maleic anhydride was 1:1, and the mass ratio of the hydroxyl-terminated polybutadiene to anhydrous dichloromethane was 1:1.
[0021] (3) Carboxyl-terminated polybutadiene and thionyl chloride with a mass ratio of 1:7 were added to the reaction kettle, stirred and heated to reflux, and reacted for 24 h. Thionyl chloride was removed by vacuum distillation to obtain acyl chloride-terminated polybutadiene.
[0022] (4) Acyl chloride-terminated polybutadiene and anhydrous tetrahydrofuran were added to the reaction kettle and stirred evenly to obtain an acyl chloride-terminated polybutadiene solution with a mass fraction of 7%. Triazine diamine compound and anhydrous tetrahydrofuran were added to the reaction kettle and stirred until the triazine diamine compound was completely dissolved to obtain a triazine diamine compound solution with a mass fraction of 10%. Then, under stirring and at 0 °C, the acyl chloride-terminated polybutadiene solution was added dropwise to the triazine diamine compound solution. After the addition was completed, triethylamine was continuously added, and then stirred and reacted at room temperature for 5 h. It was filtered, and the filtrate was subjected to vacuum distillation to remove the solvent, and a triazine-block polybutadiene was obtained. Among them, the molar ratio of the triazine diamine compound to triethylamine was 1:2.1, and the molar ratio of the acyl chloride group in the acyl chloride-terminated polybutadiene to the amino group in the triazine diamine compound was 1:1.
[0023] (5) Under stirring and at 0 °C, a chloroform solution of acryloyl chloride with a mass fraction of 20% was added dropwise to a chloroform solution of metronidazole with a mass fraction of 20%. After the addition was completed, triethylamine was added, and the mixture was continuously stirred and reacted at 0 °C for 5 h. Then, it was filtered, and the filtrate was distilled under reduced pressure to remove chloroform, obtaining acryloyl metronidazole. Among them, the molar ratio of acryloyl chloride, metronidazole, and triethylamine was 1:1:1.1. The structure of acryloyl metronidazole is as follows: 。
[0024] (6) Triazine-block polybutadiene was added to chloroform and fully dissolved to obtain a triazine-block polybutadiene solution with a mass fraction of 5%. Then, the catalyst and acryloyl metronidazole were added to the triazine-block polybutadiene solution, stirred evenly, then heated to 50 °C, and stirred and refluxed for 1 h. After cooling to room temperature, chloroform was removed by distillation under reduced pressure, obtaining a heat-resistant antibacterial additive. Among them, the mass ratio of triazine-block polybutadiene to acryloyl metronidazole was 1:5, and the catalyst was (1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxybenzylidene)ruthenium, with a mass of 0.5% of the mass of triazine-block polybutadiene.
[0025] (7) A heat-resistant antibacterial additive and ultra-high molecular weight polyethylene (with a molecular weight of 2 million) with a mass ratio of 6:100 were added to a twin-screw extruder, and melt extrusion granulation was carried out at 205 °C to obtain polyethylene pellets. Then, the polyethylene pellets were added to a compression molding mold, heated to 220 °C, a pressure of 8 MPa was applied, and after heat preservation for 0.8 h, it was cooled to room temperature with the mold, and the mold was demolded after pressure relief, obtaining an antibacterial and high-temperature resistant PE plastic product. Example 2
[0026] The preparation method of the antibacterial and high-temperature resistant PE plastic product in this example includes the following steps: (1) Cyanuric chloride and ether were added to the first reaction kettle and stirred until cyanuric chloride was fully dissolved to obtain a cyanuric chloride solution with a mass fraction of 18%. 1-Methyl-2-imidazolemethanamine, triethylamine, and ether were added to the second reaction kettle and stirred evenly to obtain a first mixed solution, and the mass fraction of 1-methyl-2-imidazolemethanamine in the first mixed solution was 23%. The temperature of the material in the first reaction kettle was adjusted to 2 °C, and then the first mixed solution was added dropwise to the first reaction kettle under stirring conditions. After the addition was completed, the material in the first reaction kettle was continuously stirred and reacted for 3.5 h. Among them, the molar ratio of cyanuric chloride, 1-methyl-2-imidazolemethanamine, and triethylamine was 1:1:1.1; Pyrazine-2,3-diyldimethanamine, triethylamine and diethyl ether were added to the third reaction kettle and stirred evenly to obtain a second mixed solution. The mass fraction of pyrazine-2,3-diyldimethanamine in the second mixed solution was 18%. The temperature of the material in the first reaction kettle was adjusted to room temperature, and then the second mixed solution was added dropwise to the first reaction kettle under stirring conditions. After the addition was completed, the material in the first reaction kettle was heated to 110 °C and stirred and reacted for 9 h, then cooled to room temperature, and diethyl ether was removed by vacuum distillation to obtain a concentrate. Then the concentrate was purified by column chromatography. The eluent used for purification was composed of methanol, ethyl acetate and petroleum ether with a volume ratio of 1:2:3. After the purification was completed, the eluent collected by purification was subjected to vacuum distillation to remove the solvent, and a triazine diamine compound was obtained. Among them, the molar ratio of pyrazine-2,3-diyldimethanamine to cyanuric chloride was 2.2:1, the molar ratio of pyrazine-2,3-diyldimethanamine to triethylamine was 1:2.3, and the structure of the triazine diamine compound was as follows: 。
[0027] (2) Hydroxyl-terminated polybutadiene was heated under vacuum to remove water, and then added to a reaction kettle. Then maleic anhydride and anhydrous dichloromethane were added to the reaction kettle, heated to 75 °C, and stirred and refluxed for 6 h. Dichloromethane was removed by vacuum distillation to obtain carboxyl-terminated polybutadiene. Among them, the hydroxyl value of the hydroxyl-terminated polybutadiene was 0.55 mmol / g, the number-average molecular weight was 3700, the molar ratio of the hydroxyl groups in the hydroxyl-terminated polybutadiene to the molar amount of maleic anhydride was 1:1, and the mass ratio of the hydroxyl-terminated polybutadiene to anhydrous dichloromethane was 1:1.1.
[0028] (3) Carboxyl-terminated polybutadiene and thionyl chloride with a mass ratio of 1:8 were added to a reaction kettle, stirred and heated to reflux, and reacted for 26 h. Thionyl chloride was removed by vacuum distillation to obtain acyl chloride-terminated polybutadiene.
[0029] (4) Acyl chloride-terminated polybutadiene and anhydrous tetrahydrofuran were added to a reaction kettle and stirred evenly to obtain an acyl chloride-terminated polybutadiene solution with a mass fraction of 8%. Triazine diamine compound and anhydrous tetrahydrofuran were added to a reaction kettle and stirred until the triazine diamine compound was completely dissolved to obtain a triazine diamine compound solution with a mass fraction of 12%. Then, under stirring and at 2 °C, the acyl chloride-terminated polybutadiene solution was added dropwise to the triazine diamine compound solution. After the addition was completed, triethylamine was added continuously, and then stirred and reacted at room temperature for 6 h. After filtration, the filtrate was subjected to vacuum distillation to remove the solvent, and a triazine-blocked polybutadiene was obtained. Among them, the molar ratio of the triazine diamine compound to triethylamine was 1:2.2, and the molar ratio of the acyl chloride groups in the acyl chloride-terminated polybutadiene to the amino groups in the triazine diamine compound was 1:1.
[0030] (5) Under stirring and at 2 °C, a chloroform solution of acryloyl chloride with a mass fraction of 25% was added dropwise to a chloroform solution of metronidazole with a mass fraction of 25%. After the addition was completed, triethylamine was added, and the mixture was continuously stirred and reacted at 3 °C for 7 h. Then, it was filtered, and the filtrate was distilled under reduced pressure to remove chloroform, obtaining acryloyl metronidazole. Among them, the molar ratio of acryloyl chloride, metronidazole, and triethylamine was 1:1:1.2. The structure of acryloyl metronidazole is as follows: 。
[0031] (6) Triazine-block polybutadiene was added to chloroform and fully dissolved to obtain a triazine-block polybutadiene solution with a mass fraction of 6%. Then, a catalyst and acryloyl metronidazole were added to the triazine-block polybutadiene solution, stirred evenly, then heated to 54 °C, and stirred and refluxed for 1.2 h. After cooling to room temperature, chloroform was removed by distillation under reduced pressure, obtaining a heat-resistant antibacterial additive. Among them, the mass ratio of triazine-block polybutadiene to acryloyl metronidazole was 1:6, and the catalyst was (1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxybenzylidene)ruthenium, with a mass of 0.6% of the mass of triazine-block polybutadiene.
[0032] (7) A heat-resistant antibacterial additive and ultra-high molecular weight polyethylene (with a molecular weight of 2 million) with a mass ratio of 7:100 were added to a twin-screw extruder and melt-extruded and pelletized at 210 °C to obtain polyethylene pellets. Then, the polyethylene pellets were added to a molding die, heated to 225 °C, a pressure of 9 MPa was applied, and after heat preservation for 1 h, it was cooled to room temperature with the die, and the pressure was released and demolded to obtain an antibacterial and high-temperature resistant PE plastic product. Example 3
[0033] The preparation method of the antibacterial and high-temperature resistant PE plastic product in this example includes the following steps: (1) Cyanuric chloride and ether were added to the first reaction kettle and stirred until cyanuric chloride was fully dissolved to obtain a cyanuric chloride solution with a mass fraction of 20%. 1-Methyl-2-imidazole methylamine, triethylamine, and ether were added to the second reaction kettle and stirred evenly to obtain a first mixed solution, and the mass fraction of 1-methyl-2-imidazole methylamine in the first mixed solution was 25%. The temperature of the material in the first reaction kettle was adjusted to 5 °C, and then the first mixed solution was added dropwise to the first reaction kettle under stirring conditions. After the addition was completed, the material in the first reaction kettle was continuously stirred and reacted for 4 h. Among them, the molar ratio of cyanuric chloride, 1-methyl-2-imidazole methylamine, and triethylamine was 1:1:1.2; Pyrazine-2,3-diyldimethanamine, triethylamine, and diethyl ether were added to the third reaction kettle and stirred evenly to obtain a second mixed solution. The mass fraction of pyrazine-2,3-diyldimethanamine in the second mixed solution was 20%. The temperature of the material in the first reaction kettle was adjusted to room temperature, and then the second mixed solution was added dropwise to the first reaction kettle under stirring conditions. After the addition was completed, the material in the first reaction kettle was heated to 115 °C and stirred for reaction for 10 h, cooled to room temperature, and diethyl ether was removed by vacuum distillation to obtain a concentrate. Then, the concentrate was purified by column chromatography. The eluent used for purification was composed of methanol, ethyl acetate, and petroleum ether with a volume ratio of 1:2:3. After the purification was completed, the eluent collected by purification was subjected to vacuum distillation to remove the solvent, and a triazine diamine compound was obtained. Among them, the molar ratio of pyrazine-2,3-diyldimethanamine to cyanuric chloride was 2.3:1, the molar ratio of pyrazine-2,3-diyldimethanamine to triethylamine was 1:2.4, and the structure of the triazine diamine compound was as follows: 。
[0034] (2) Hydroxyl-terminated polybutadiene was heated under vacuum to remove water and then added to the reaction kettle. Then, maleic anhydride and anhydrous dichloromethane were added to the reaction kettle, heated to 80 °C, and stirred and refluxed for 7 h. Dichloromethane was removed by vacuum distillation to obtain carboxyl-terminated polybutadiene. Among them, the hydroxyl value of the hydroxyl-terminated polybutadiene was 0.55 mmol / g, the number-average molecular weight was 3700, the molar ratio of the hydroxyl group in the hydroxyl-terminated polybutadiene to the molar amount of maleic anhydride was 1:1, and the mass ratio of the hydroxyl-terminated polybutadiene to anhydrous dichloromethane was 1:1.2.
[0035] (3) Carboxyl-terminated polybutadiene and thionyl chloride with a mass ratio of 1:9 were added to the reaction kettle, stirred and heated to reflux, and reacted for 28 h. Thionyl chloride was removed by vacuum distillation to obtain acyl chloride-terminated polybutadiene.
[0036] (4) Acyl chloride-terminated polybutadiene and anhydrous tetrahydrofuran were added to the reaction kettle and stirred evenly to obtain an acyl chloride-terminated polybutadiene solution with a mass fraction of 7-9%. Triazine diamine compound and anhydrous tetrahydrofuran were added to the reaction kettle and stirred until the triazine diamine compound was completely dissolved to obtain a triazine diamine compound solution with a mass fraction of 15%. Then, under stirring and at 5 °C, the acyl chloride-terminated polybutadiene solution was added dropwise to the triazine diamine compound solution. After the addition was completed, triethylamine was continuously added, and then stirred at room temperature for 8 h. After filtration, the filtrate was subjected to vacuum distillation to remove the solvent, and triazine-blocked polybutadiene was obtained. Among them, the molar ratio of the triazine diamine compound to triethylamine was 1:2.3, and the molar ratio of the acyl chloride group in the acyl chloride-terminated polybutadiene to the amino group in the triazine diamine compound was 1:1.
[0037] (5) Under stirring and at 5 °C, a chloroform solution of acryloyl chloride with a mass fraction of 30% was added dropwise to a chloroform solution of metronidazole with a mass fraction of 30%. After the addition was completed, triethylamine was added, and the mixture was continuously stirred at 5 °C for 8 h. Then, it was filtered, and the filtrate was distilled under reduced pressure to remove chloroform, obtaining acryloyl metronidazole. Among them, the molar ratio of acryloyl chloride, metronidazole, and triethylamine was 1:1:1.2. The structure of acryloyl metronidazole is as follows: .
[0038] (6) Triazine-block polybutadiene was added to chloroform and fully dissolved to obtain a triazine-block polybutadiene solution with a mass fraction of 7%. Then, the catalyst and acryloyl metronidazole were added to the triazine-block polybutadiene solution, stirred evenly, then heated to 60 °C, and stirred and refluxed for 1.5 h. After cooling to room temperature, chloroform was removed by distillation under reduced pressure to obtain a heat-resistant antibacterial additive. Among them, the mass ratio of triazine-block polybutadiene to acryloyl metronidazole was 1:8, and the catalyst was (1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxybenzylidene)ruthenium, with a mass of 0.8% of the mass of triazine-block polybutadiene.
[0039] (7) A heat-resistant antibacterial additive and ultra-high molecular weight polyethylene (with a molecular weight of 2 million) with a mass ratio of 8:100 were added to a twin-screw extruder and melt-extruded and granulated at 215 °C to obtain polyethylene pellets. Then, the polyethylene pellets were added to a compression molding die, heated to 230 °C, a pressure of 10 MPa was applied, and after heat preservation for 1.2 h, it was cooled to room temperature with the die, the pressure was released, and the mold was demolded to obtain an antibacterial and high-temperature resistant PE plastic product. Example 4
[0040] The difference between the preparation method of the antibacterial and high-temperature resistant PE plastic product in this example and the preparation method of the antibacterial and high-temperature resistant PE plastic product in Example 1 is only that the hydroxyl value of the hydroxyl-terminated polybutadiene in step (2) of the preparation method of the antibacterial and high-temperature resistant PE plastic product in this example is 0.68 mmol / g, and the number-average molecular weight is 3000. Example 5
[0041] The difference between the preparation method of the antibacterial and high-temperature resistant PE plastic product in this example and the preparation method of the antibacterial and high-temperature resistant PE plastic product in Example 1 is only that the hydroxyl value of the hydroxyl-terminated polybutadiene in step (2) of the preparation method of the antibacterial and high-temperature resistant PE plastic product in this example is 0.47 mmol / g, and the number-average molecular weight is 4500. Example 6
[0042] The preparation method of the antibacterial and high-temperature resistant PE plastic product of this embodiment is only different from that of the antibacterial and high-temperature resistant PE plastic product of Embodiment 1 in that the hydroxyl value of the hydroxyl-terminated polybutadiene in step (2) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this embodiment is 0.73 mmol / g, and the number-average molecular weight is 2800. Example 7
[0043] The preparation method of the antibacterial and high-temperature resistant PE plastic product of this embodiment is only different from that of the antibacterial and high-temperature resistant PE plastic product of Embodiment 1 in that 1-methyl-2-imidazolemethanamine is replaced by 2-pyrimidine methanamine in step (1) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this embodiment.
[0044] Comparative Example 1 The preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is only different from that of the antibacterial and high-temperature resistant PE plastic product of Embodiment 1 in that the heat-resistant antibacterial additive in step (7) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is composed of cyanuric chloride, 1-methyl-2-imidazolemethanamine, pyrazine-2,3-diyldimethylamine, hydroxyl-terminated polybutadiene and metronidazole. The molar ratio of cyanuric chloride, 1-methyl-2-imidazolemethanamine and pyrazine-2,3-diyldimethylamine is 1:1:2, the molar ratio of the amount of hydroxyl groups in hydroxyl-terminated polybutadiene to the amount of amino groups in pyrazine-2,3-diyldimethylamine is 1:1, and the mass ratio of metronidazole to the sum of the masses of cyanuric chloride, 1-methyl-2-imidazolemethanamine, pyrazine-2,3-diyldimethylamine and hydroxyl-terminated polybutadiene is 1:5.
[0045] Comparative Example 2 The preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is only different from that of the antibacterial and high-temperature resistant PE plastic product of Embodiment 1 in that the triazine diamine compound is replaced by pyrazine-2,3-diyldimethylamine in step (4) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example.
[0046] Comparative Example 3 The preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is only different from that of the antibacterial and high-temperature resistant PE plastic product of Embodiment 1 in that the triazine diamine compound is replaced by melamine in step (4) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example.
[0047] Comparative Example 4 The preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example is different from that of the antibacterial and high-temperature resistant PE plastic products in Example 1 only in that in step (6) of the preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example, propylene metronidazole is replaced by propylene erythromycin. The preparation method of propylene erythromycin is as follows: Under stirring and at 0 °C, a chloroform solution of acryloyl chloride with a mass fraction of 20% is added dropwise to a chloroform solution of erythromycin with a mass fraction of 20 - 30%. After the addition is completed, triethylamine is added, and the mixture is continuously stirred and reacted at 0 °C for 5 h. Then, it is filtered, and the filtrate is distilled under reduced pressure to remove chloroform to obtain propylene erythromycin. Among them, the molar ratio of acryloyl chloride to triethylamine is 1:1.1, and the molar ratio of acryloyl chloride to the hydroxyl group in erythromycin is 1:1.
[0048] Comparative Example 5 The preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example is different from that of the antibacterial and high-temperature resistant PE plastic products in Example 1 only in that in step (6) of the preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example, propylene metronidazole is replaced by propylene chloramphenicol. The preparation method of propylene chloramphenicol is as follows: Under stirring and at 0 °C, a chloroform solution of acryloyl chloride with a mass fraction of 20% is added dropwise to a chloroform solution of chloramphenicol with a mass fraction of 20%. After the addition is completed, triethylamine is added, and the mixture is continuously stirred and reacted at 0 °C for 5 h. Then, it is filtered, and the filtrate is distilled under reduced pressure to remove chloroform to obtain propylene chloramphenicol. Among them, the molar ratio of acryloyl chloride to triethylamine is 1:1.1, and the molar ratio of acryloyl chloride to the hydroxyl group in chloramphenicol is 1:1.
[0049] Comparative Example 6 The preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example is different from that of the antibacterial and high-temperature resistant PE plastic products in Example 1 only in that in step (6) of the preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example, propylene metronidazole is replaced by propylene piperacillin. The preparation method of propylene piperacillin is as follows: Under stirring and at 0 °C, a chloroform solution of acryloyl chloride with a mass fraction of 20% is added dropwise to a chloroform solution of piperacillin with a mass fraction of 20%. After the addition is completed, triethylamine is added, and the mixture is continuously stirred and reacted at 0 °C for 5 h. Then, it is filtered, and the filtrate is distilled under reduced pressure to remove chloroform to obtain propylene piperacillin. Among them, the molar ratio of acryloyl chloride to triethylamine is 1:1.1, and the molar ratio of acryloyl chloride to the hydroxyl group in piperacillin is 1:1.
[0050] Comparative Example 7 The preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example is different from that of the antibacterial and high-temperature resistant PE plastic products in Example 1 only in that in step (7) of the preparation method of the antibacterial and high-temperature resistant PE plastic products in this comparative example, the addition amount of the heat-resistant antibacterial additive is 0.
[0051] Comparative Example 8 The preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is only different from that of the antibacterial and high-temperature resistant PE plastic product of Example 1 in that 1-methyl-2-imidazolemethanamine is replaced by 3-pyridazine methanamine in step (1) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example.
[0052] Comparative Example 9 The preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is only different from that of the antibacterial and high-temperature resistant PE plastic product of Example 1 in that 1-methyl-2-imidazolemethanamine is replaced by 5-pyrimidine methanamine in step (1) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example.
[0053] Comparative Example 10 The preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example is only different from that of the antibacterial and high-temperature resistant PE plastic product of Example 1 in that 1-methyl-2-imidazolemethanamine is replaced by 2-methylaminopyrazine in step (1) of the preparation method of the antibacterial and high-temperature resistant PE plastic product of this comparative example.
[0054] Test Example In order to evaluate the comprehensive performance of the antibacterial and high-temperature resistant PE plastic products prepared in each example and comparative example, the Vicat heat distortion temperature, tensile strength, notched impact strength, heat resistance, flame retardancy and antibacterial property of the antibacterial and high-temperature resistant PE plastic products prepared in each example and comparative example were respectively tested. Among them, the Vicat heat distortion temperature was tested according to the method specified in Standard GB / T1633 - 2000, with a load of 4 kg during the test and a heating rate of 120 °C / 60 min; the tensile strength was tested according to the method specified in Standard GB / T1040 - 2006, and the notched impact strength was tested according to the method specified in Standard GB / T1843 - 2008; the heat resistance was measured using a thermogravimetric analyzer, and the initial decomposition temperature T0 and the decomposition temperature T5% when the weight loss rate reached 5% of the antibacterial and high-temperature resistant PE plastic product were recorded during the test; the flame retardancy was tested according to the method specified in Standard GB / T2406 - 93, and the test result was expressed as the oxygen index. The antibacterial property was tested according to the method specified in Standard QB / T2591 - 2003. Staphylococcus aureus and Escherichia coli were selected as the experimental bacterial populations during the test, and the test result was expressed as the antibacterial rate. The comprehensive performance of the antibacterial and high-temperature resistant PE plastic products prepared in each example and comparative example is shown in Table 1.
[0055] Table 1 Comprehensive Performance of Antibacterial and High-Temperature Resistant PE Plastic Products
[0056] As can be seen from Table 1, the antibacterial and high-temperature resistant PE plastic products of the present invention are prepared by blending and melt-extruding a heat-resistant antibacterial additive and ultra-high molecular weight polyethylene, and have good mechanical properties, heat-resistant flame-retardant properties and antibacterial properties. The elongation at break can reach up to 118% at most, the oxygen index can reach up to 32.6 at most, and the antibacterial rate can reach up to 99.9% at most, which is significantly higher than that of pure ultra-high molecular weight polyethylene. Among them, the heat-resistant antibacterial additive contains a triazine chain segment, a pyrazine chain segment, a heterocyclic amine side chain and a metronidazole side chain, and each group chain segment has a synergistic cooperation effect to ensure that the PE plastic product has good heat-resistant flame-retardant properties and antibacterial properties. After the polybutadiene chain segment in the heat-resistant antibacterial additive undergoes an olefin metathesis reaction with propylene metronidazole, the double bond in the polybutadiene chain segment becomes a carbon-carbon single bond, forming a carbon-carbon single bond structure identical to that of polypropylene, improving the affinity between the heat-resistant antibacterial additive and ultra-high molecular weight polyethylene, and avoiding uneven dispersion of the heat-resistant antibacterial additive in the PE plastic product, which affects the improvement of heat-resistant flame-retardant properties and antibacterial properties.
[0057] As can be seen from Example 1 and Examples 5-6, the hydroxyl value and number-average molecular weight of the hydroxyl-terminated polybutadiene will affect the heat-resistant flame-retardant properties and antibacterial properties of the final PE plastic product. If the hydroxyl value and number-average molecular weight of the hydroxyl-terminated polybutadiene are too large or too small, the heat-resistant flame-retardant properties and antibacterial properties of the PE plastic product will show a downward trend. The above results indicate that in order to obtain the PE plastic product with the best performance, it is necessary to ensure that the ratio of the polybutadiene chain segment and other functional chain segments (triazine chain segment, pyrazine chain segment, heterocyclic amine side chain, metronidazole side chain) is within a suitable range.
[0058] As can be seen from Example 1 and Example 7, the heat-resistant flame-retardant properties and antibacterial properties of the PE plastic product prepared when the heterocyclic amine side chain is a 2-pyrimidine methylamine chain segment are better than those of the PE plastic product prepared when the heterocyclic amine side chain is a 1-methyl-2-imidazole methylamine chain segment, indicating that in the molecular chain of the heat-resistant antibacterial additive of the present invention, the 2-pyrimidine methylamine chain segment has the best compounding effect with other functional chain segments (triazine chain segment, pyrazine chain segment, heterocyclic amine side chain, metronidazole side chain). In addition, as can be seen from Example 1 and Comparative Examples 8-10, the heat-resistant flame-retardant properties and antibacterial properties of the PE plastic product prepared when the heterocyclic amine side chain is 3-pyridazine methylamine, 5-pyrimidine methylamine or 2-methylaminopyrazine cannot meet the requirements, indicating that the 3-pyridazine methylamine, 5-pyrimidine methylamine or 2-methylaminopyrazine chain segment cannot be well compounded with other functional chain segments (triazine chain segment, pyrazine chain segment, heterocyclic amine side chain, metronidazole side chain) and cannot play a synergistic cooperation role.
[0059] As can be seen from Example 1 and Comparative Examples 4-6, when the metronidazole side chain in the molecular chain of the heat-resistant antibacterial additive in Example 1 is replaced with an erythromycin, chloramphenicol, or piperacillin segment, the heat-resistant flame-retardant performance and antibacterial performance of the prepared PE plastic products cannot meet the usage requirements. This is because the erythromycin, chloramphenicol, or piperacillin segment lacks heat-resistant groups, and at the same time, these three side chains cannot cooperate well with other functional segments (triazine segment, pyrazine segment, heterocyclic amine side chain) and the polybutadiene segment.
[0060] As can be seen from Example 1 and Comparative Examples 1-3, when the molecular chain of the heat-resistant antibacterial additive is disassembled into separate small molecular segments, or lacks the triazine segment or the heterocyclic amine side chain, the heat-resistant flame-retardant performance and antibacterial performance of the prepared PE plastic products are significantly reduced, proving that the triazine segment, pyrazine segment, heterocyclic amine side chain, and metronidazole side chain can cooperate with each other to jointly improve the heat-resistant flame-retardant performance and antibacterial performance of PE plastic products.
Claims
1. A preparation method of an antibacterial and high-temperature resistant PE plastic product, characterized in that It includes the following steps: (1) React hydroxyl-terminated polybutadiene with maleic anhydride to obtain carboxyl-terminated polybutadiene. The molar ratio of the hydroxyl groups in the hydroxyl-terminated polybutadiene to the maleic anhydride is 1:1; the hydroxyl value of the hydroxyl-terminated polybutadiene is 0.47 - 0.73 mmol / g, and the number-average molecular weight is 2800 - 4500; (2) React the carboxyl-terminated polybutadiene with thionyl chloride to obtain acyl chloride-terminated polybutadiene; (3) React the acyl chloride-terminated polybutadiene with a triazine diamine compound to obtain triazine-block polybutadiene. The molar ratio of the acyl chloride groups in the acyl chloride-terminated polybutadiene to the amino groups in the triazine diamine compound is 1:1; the structure of the triazine diamine compound is shown in Formula I or Formula II: ； (4) Perform an olefin metathesis reaction on the triazine-block polybutadiene and propargyl metronidazole to obtain a heat-resistant antibacterial additive. The mass ratio of the triazine-block polybutadiene to propargyl metronidazole is 1:5 - 8; the structure of propargyl metronidazole is as follows: ； (5) Melt-extrude and pelletize a heat-resistant antibacterial additive and ultra-high molecular weight polyethylene with a mass ratio of 6 - 8:100 to obtain polyethylene pellets; then perform compression molding on the polyethylene pellets to obtain an antibacterial and high-temperature resistant PE plastic product.
2. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to claim 1, wherein, The preparation method of the triazine diamine compound is as follows: React cyanuric chloride with a heterocyclic amine compound and pyrazine-2,3-diyldimethanamine in sequence to obtain the triazine diamine compound; the heterocyclic amine compound is 1-methyl-2-imidazolemethanamine or 2-pyrimidine methanamine; the molar ratio of cyanuric chloride, the heterocyclic amine compound, and pyrazine-2,3-diyldimethanamine is 1:1:2.1 - 2.
3.
3. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to claim 2, characterized in that, When reacting cyanuric chloride with the heterocyclic amine compound, the temperature is 0 - 5 °C and the time is 3 - 4 h; when reacting cyanuric chloride with pyrazine-2,3-diyldimethanamine, the temperature is 105 - 115 °C and the time is 8 - 10 h.
4. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The reaction temperature of the hydroxyl-terminated polybutadiene and maleic anhydride is 70 - 80 °C, and the time is 5 - 7 h.
5. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The mass ratio of the carboxyl-terminated polybutadiene to thionyl chloride is 1:7 - 9.
6. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The reaction temperature of the acyl chloride-terminated polybutadiene and the triazine diamine compound is 0 - 5 °C, and the time is 5 - 8 h.
7. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The temperature of the olefin metathesis reaction is 50 - 60 °C, the time is 1 - 1.5 h, and the catalyst during the reaction is (1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro(o-isopropoxybenzylidene)ruthenium, and the mass is 0.5 - 0.8% of the mass of the triazine-block polybutadiene.
8. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The hydroxyl value of the hydroxyl-terminated polybutadiene is 0.55 - 0.68 mmol / g, and the number-average molecular weight is 3000 - 3700.
9. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The temperature of the melt-extrusion granulation is 205 - 215 °C.
10. The preparation method of the antibacterial and high-temperature resistant PE plastic product according to any one of claims 1-3, characterized in that, The heating temperature for the compression molding is 220 - 230 °C, the time is 0.8 - 1.2 h, and the pressure is 8 - 10 MPa.