Antibacterial master batch based on polyvinyl chloride and preparation method thereof

Abstract

The invention relates to the technical field of high polymer materials, and discloses an antibacterial master batch based on polyvinyl chloride and a preparation method thereof.The antibacterial master batch comprises the following raw materials: polyvinyl chloride, a stabilizer, a lubricant, a compatibilizer, a composite antibacterial component and a toughening additive, polyvinyl chloride serves as a plastic base material, the composite antibacterial component is added, and the toughening additive is added; the prepared antibacterial master batch is excellent in antibacterial performance, has broad-spectrum antibacterial and stable long-acting antibacterial effects, and can effectively reduce health risks caused by microorganisms such as bacteria and molds and inhibit adverse effects of metabolic activities of the microorganisms on polyvinyl chloride, so that the service life of the antibacterial master batch is prolonged; by adding the toughening additive, the prepared antibacterial master batch is excellent in mechanical property and impact toughness, can absorb and disperse energy under the action of external force, can meet the market demand, and has a wide application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to an antibacterial masterbatch based on polyvinyl chloride and a preparation method thereof. Background Art

[0002] With the development of society, the continuous improvement of people's living standards and the enhancement of health and hygiene awareness, plastic products with antibacterial effects have attracted attention and favor from the consumer market. Antibacterial masterbatch is a kind of plastic particle with antibacterial effect, which is usually a mixture of antibacterial substances and plastic substrates. Antibacterial masterbatch has a strong antibacterial effect and a broad-spectrum antibacterial effect. It can quickly kill bacteria, molds and other microorganisms, reduce their harm to the human body, and still has stable antibacterial properties after long-term use. The antibacterial effect is long-lasting. It is used in packaging materials, medical equipment, building materials, industrial products and other fields, which significantly improves the safety and hygiene level of products, meets people's pursuit of health, and can extend the service life of products to a certain extent.

[0003] Polyvinyl chloride is a widely used polymer material at present. It is a polymer formed by polymerization of vinyl chloride monomer under the conditions of initiator or light and heat according to the mechanism of free radical polymerization reaction. It has multiple physical and chemical properties. Polyvinyl chloride is corrosion-resistant and can resist the erosion of chemical substances such as acid, alkali and salt; it has good heat resistance and can maintain stable performance at high temperature; it has good insulation, good plasticity and is easy to process, low price, excellent flame retardant performance, is not easy to burn and will self-extinguish during combustion; therefore, polyvinyl chloride can be used as a plastic substrate for antibacterial masterbatch, but polyvinyl chloride itself does not have antibacterial properties, so polyvinyl chloride products are easily contaminated by various microorganisms such as bacteria and molds during use, and polyvinyl chloride has poor mechanical properties and impact toughness. It is easy to be damaged or broken when subjected to external forces, and its application in some fields is limited. Therefore, for polyvinyl chloride as a plastic substrate, the present invention modifies it by adding a composite antibacterial component and a toughening additive to prepare an antibacterial masterbatch with excellent antibacterial performance, excellent mechanical properties and excellent impact toughness, effectively reducing the health risks brought by microorganisms such as bacteria and molds, meeting market demand, and having broad application prospects. Summary of the invention

[0004] In order to solve the problems mentioned in the background technology, the object of the present invention is to provide an antibacterial masterbatch based on polyvinyl chloride and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A polyvinyl chloride-based antibacterial masterbatch comprises the following raw materials in parts by weight: 70-85 parts of polyvinyl chloride, 2-6 parts of a stabilizer, 3-5 parts of a lubricant, 0.5-2 parts of a compatibilizer, 3-6 parts of a composite antibacterial component, and 4-8 parts of a toughening additive.

[0007] Furthermore, the stabilizer is a calcium zinc stabilizer or a barium zinc stabilizer; and the lubricant is polyethylene wax or microcrystalline wax.

[0008] Furthermore, the preparation method of the compatibilizer is as follows:

[0009] After polyvinyl chloride, maleic anhydride and dipentadienyl vulcanizing agent are uniformly mixed, stirred at a stirring rate of 500-600 r / min for 5-10 minutes, added into a twin-screw extruder, extruded at 200-220° C., granulated and dried to obtain a compatibilizer.

[0010] Furthermore, the preparation method of the composite antibacterial component comprises the following steps:

[0011] Step A: adding branched polyethyleneimine and o-vanillin to ethanol, stirring evenly, adding ammonia water to adjust the pH, placing the system in a water bath at 50-70° C., stirring for 2-4 hours, separating the product, and obtaining an antibacterial intermediate;

[0012] Step B: adding the antibacterial intermediate product and CuCl2·2H2O into anhydrous ethanol, mixing evenly, heating under reflux for 3-5h, separating the product, washing, and drying to obtain a composite antibacterial component.

[0013] By adopting the above technical scheme, the primary amino group in the branched polyethyleneimine structure can react with the aldehyde group in the o-vanillin structure under alkaline conditions to produce a Schiff base reaction to obtain an antibacterial intermediate, and the antibacterial intermediate can be complexed and coordinated with copper ions to form a copper complex to obtain a composite antibacterial component. The composite antibacterial component contains natural antibacterial substances o-vanillin and copper ions to form an organic-inorganic composite antibacterial substance, which has a broad-spectrum antibacterial effect, can inhibit the activity of essential enzymes in microorganisms such as bacteria and molds, and bind to receptors on the cell membranes of microorganisms such as bacteria and molds to destroy the microbial cell membranes, so that the intracellular substances leak out to achieve a bactericidal effect. In addition, the composite antibacterial component can be cross-linked with the polyvinyl chloride matrix, so that the composite antibacterial component is stably present in the polyvinyl chloride matrix, preventing the precipitation and migration of o-vanillin and copper ions during long-term use, resulting in a decrease in antibacterial performance, and achieving a stable and long-lasting antibacterial effect, thereby effectively reducing the health risks brought by microorganisms such as bacteria and molds and inhibiting the adverse effects of microbial metabolic activities on the polyvinyl chloride matrix, thereby extending the service life of the antibacterial masterbatch.

[0014] Furthermore, in step A, the weight average molecular weight of the branched polyethyleneimine is 1800.

[0015] Furthermore, in step A, the pH is 8-9.

[0016] Furthermore, the preparation method of the toughening additive comprises the following steps:

[0017] S1: adding bamboo fiber into a potassium hydroxide solution with a mass fraction of 8-10%, heating to 40-50°C, stirring for 1-2h, filtering, washing, and drying to obtain alkali-treated bamboo fiber;

[0018] S2: dispersing the alkali-treated bamboo fiber in acetone, adding 3-mercaptopropionic acid and a catalyst, stirring evenly, heating under reflux for 2-4 hours, filtering, washing, and drying to obtain thiolated bamboo fiber;

[0019] S3: Disperse the thiolated bamboo fiber in N,N-dimethylformamide, add eucommia gum and photoinitiator, stir evenly, irradiate under ultraviolet light at room temperature for 6-8 hours, filter, wash and dry to obtain a toughening additive.

[0020] By adopting the above technical scheme, bamboo fiber can expose more hydroxyl groups after alkali treatment, and under the action of a catalyst, the hydroxyl groups on the surface of the bamboo fiber can undergo an esterification reaction with the carboxyl groups in the structure of 3-mercaptopropionic acid, thereby introducing a sulfhydryl group on the surface of the alkalized bamboo fiber to obtain a sulfhydryl bamboo fiber, and under the irradiation of a photoinitiator and ultraviolet light, the sulfhydryl groups in the sulfhydryl bamboo fiber can undergo a click reaction with the olefin groups in the structure of eucommia gum to obtain a toughening additive. The toughening additive contains bamboo fiber with an antibacterial effect, and the bamboo fiber has good compatibility with the polyvinyl chloride matrix, can be evenly dispersed in the polyvinyl chloride matrix, and enhances the mechanical properties and impact toughness of the polyvinyl chloride matrix. In addition, eucommia gum has a good toughening effect, and the two can play a synergistic toughening effect. At the same time, the toughening additive can produce a hydrogen bond with the polyvinyl chloride matrix under the action of a compatibilizer, thereby forming a polymer network structure, and the molecular chain is more dense. The toughening additive can become a stress concentration point, and when subjected to an external force, it absorbs and disperses energy, and further enhances the impact toughness.

[0021] Furthermore, in S2, the catalyst is dicyclohexylcarbodiimide and 4-dimethylaminopyridine in a mass ratio of 6-7:2-3.

[0022] Furthermore, in S3, the photoinitiator is benzoin dimethyl ether or benzoin isopropyl ether.

[0023] A method for preparing an antibacterial masterbatch based on polyvinyl chloride comprises the following steps:

[0024] Step 1: Add polyvinyl chloride, stabilizer, lubricant, compatibilizer, composite antibacterial component and toughening additive into a high-speed mixer, set the speed to 500-800 r / min, stir and mix for 20-60 minutes to obtain a mixture;

[0025] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 110-130°C, set the head temperature to 120-140°C, extrude and granulate, and cool the mixture to obtain an antibacterial masterbatch.

[0026] Beneficial effects of the present invention:

[0027] The present invention adds a composite antibacterial component and a toughening additive to the polyvinyl chloride base material to prepare an antibacterial masterbatch with excellent antibacterial performance, mechanical properties and impact toughness. The antibacterial rate can reach 99.9%, the tensile strength can reach 50.6MPa, and the impact strength can reach 34.3KJ / m 2 It can effectively reduce health risks, inhibit the metabolic activities of microorganisms such as bacteria and mold from affecting polyvinyl chloride substrates, meet market demand, and has broad application prospects.

[0028] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0030] Figure 1 is the infrared spectrum of the antibacterial intermediate product of the present invention;

[0031] Figure 2 This is the infrared spectrum of the toughening additive in the present invention. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The preparation methods of the composite antibacterial components, toughening additives and compatibilizers in the following examples and comparative examples of the present invention are as follows:

[0034] 1. Preparation of composite antibacterial components

[0035] Step A: 3.6 g of branched polyethyleneimine with a weight average molecular weight of 1800 and 3 g of o-vanillin were added to ethanol, stirred evenly, and then ammonia water was added to adjust the pH to 8. The system was placed in a water bath at 60° C., stirred for 3 h, and the product was separated to obtain an antibacterial intermediate;

[0036] Step B: Add 5.2 g of the antibacterial intermediate product and 3.4 g of CuCl2·2H2O into anhydrous ethanol, mix well, heat under reflux for 4 h, separate the product, wash, and dry to obtain a composite antibacterial component.

[0037] Use FTIR-800S Fourier transform infrared spectrometer to conduct infrared testing on antibacterial intermediates, such as Figure 1 As shown in the figure, analysis shows that in the infrared spectrum of the antibacterial intermediate, 3200cm -1 The absorption peak of -OH appeared at 3100-3000cm -1 The absorption peak of CH in the benzene ring appeared at 1625 cm -1 The absorption peaks of Schiff base C=N appeared at 1310 and 1008 cm -1 The absorption peak of CN appears at .

[0038] 2. Preparation of toughening additives

[0039] S1: adding 4 g of bamboo fiber into a potassium hydroxide solution with a mass fraction of 8%, heating to 45°C, stirring for 1.5 hours, filtering, washing, and drying to obtain alkali-treated bamboo fiber;

[0040] S2: 3.2 g of alkali-treated bamboo fiber was dispersed in acetone, 4 g of 3-mercaptopropionic acid, 0.6 g of dicyclohexylcarbodiimide and 0.2 g of 4-dimethylaminopyridine were added, and the mixture was stirred evenly, and then heated under reflux for 3 h, filtered, washed and dried to obtain thiolated bamboo fiber;

[0041] S3: Disperse 3 g of thiolated bamboo fiber in N,N-dimethylformamide, add 2.4 g of eucommia gum and 0.4 g of benzoin dimethyl ether, stir evenly, irradiate under ultraviolet light at room temperature for 6 h, filter, wash and dry to obtain a toughening additive.

[0042] Use FTIR-800S Fourier transform infrared spectrometer to conduct infrared test on toughening additives, such as Figure 2 As shown in the figure, analysis shows that in the infrared spectrum of the toughening additive, 3300cm -1 The absorption peak of -OH in bamboo fiber appeared at 2900-2800cm -1The absorption peaks of CH in methyl and methylene appeared at 1732 cm -1 The absorption peak of ester group C=O appeared at 1174 cm -1 The absorption peak of CSC appears at .

[0043] 3. Preparation of Compatibilizer

[0044] 8g of polyvinyl chloride, 2g of maleic anhydride and 0.1g of dipentadienyl vulcanizer were mixed evenly, stirred at a stirring rate of 550r / min for 10min, added into a twin-screw extruder, extruded at 210°C, granulated and dried to obtain a compatibilizer.

[0045] Example 1

[0046] Preparation of antibacterial masterbatch

[0047] Step 1: Add 70g of polyvinyl chloride, 2g of calcium zinc stabilizer, 3g of polyethylene wax, 0.5g of compatibilizer, 3g of composite antibacterial component, and 4g of toughening additive into a high-speed mixer, set the speed to 500r / min, stir and mix for 20min to obtain a mixture;

[0048] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 110° C., set the head temperature to 120° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0049] Example 2

[0050] Preparation of antibacterial masterbatch

[0051] Step 1: Add 75g of polyvinyl chloride, 4g of calcium zinc stabilizer, 4g of polyethylene wax, 1g of compatibilizer, 4g of composite antibacterial component, and 6g of toughening additive into a high-speed mixer, set the speed to 600r / min, stir and mix for 30min to obtain a mixture;

[0052] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 120° C., set the head temperature to 130° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0053] Example 3

[0054] Preparation of antibacterial masterbatch

[0055] Step 1: Add 80g of polyvinyl chloride, 5g of calcium zinc stabilizer, 5g of polyethylene wax, 1.5g of compatibilizer, 5g of composite antibacterial component, and 7g of toughening additive into a high-speed mixer, set the speed to 700r / min, stir and mix for 40min to obtain a mixture;

[0056] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 125° C., set the head temperature to 135° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0057] Example 4

[0058] Preparation of antibacterial masterbatch

[0059] Step 1: Add 85g of polyvinyl chloride, 6g of calcium zinc stabilizer, 5g of polyethylene wax, 2g of compatibilizer, 6g of composite antibacterial component, and 8g of toughening additive into a high-speed mixer, set the speed to 800r / min, stir and mix for 60min to obtain a mixture;

[0060] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 130° C., set the head temperature to 140° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0061] Comparative Example 1

[0062] Preparation of antibacterial masterbatch

[0063] Step 1: Add 75g of polyvinyl chloride, 4g of calcium zinc stabilizer, 4g of polyethylene wax, 1g of compatibilizer, and 6g of toughening additive into a high-speed mixer, set the speed to 600r / min, stir and mix for 30min to obtain a mixture;

[0064] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 120° C., set the head temperature to 130° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0065] Comparative Example 2

[0066] Preparation of antibacterial masterbatch

[0067] Step 1: Add 75g of polyvinyl chloride, 4g of calcium zinc stabilizer, 4g of polyethylene wax, 1g of compatibilizer, and 4g of composite antibacterial component into a high-speed mixer, set the speed to 600r / min, stir and mix for 30min to obtain a mixture;

[0068] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 120° C., set the head temperature to 130° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0069] Comparative Example 3

[0070] Preparation of antibacterial masterbatch

[0071] Step 1: Add 75g of polyvinyl chloride, 4g of calcium zinc stabilizer, 4g of polyethylene wax, 1g of compatibilizer, 4g of o-vanillin, and 6g of toughening additive into a high-speed mixer, set the speed to 600r / min, stir and mix for 30min to obtain a mixture;

[0072] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 120° C., set the head temperature to 130° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0073] Comparative Example 4

[0074] Preparation of antibacterial masterbatch

[0075] Step 1: Add 75g of polyvinyl chloride, 4g of calcium zinc stabilizer, 4g of polyethylene wax, 1g of compatibilizer, 4g of composite antibacterial component, and 6g of bamboo fiber into a high-speed mixer, set the speed to 600r / min, stir and mix for 30min to obtain a mixture;

[0076] Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 120° C., set the head temperature to 130° C., extrude and granulate, and after standing and cooling, obtain the antibacterial masterbatch.

[0077] The antibacterial masterbatches prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were prepared into test samples by injection molding, and the following performance tests were performed:

[0078] After the samples were placed at room temperature for 60 days, the antibacterial rate of the samples was tested according to GB / T 31402-2023 standard; the tensile strength of the samples was tested according to GB / T 1040.1-2018 standard; the impact strength of the samples was tested according to GB / T 1843-2008 standard. The test results are shown in the following table:

[0079]

[0080]

[0081] As can be seen from the above table, by adding the composite antibacterial component and the toughening additive to the polyvinyl chloride matrix, the antibacterial masterbatch prepared in Examples 1 to 4 has excellent antibacterial properties, mechanical properties and impact toughness. In Comparative Example 1, no composite antibacterial component was added, and the organic natural antibacterial substance o-vanillin and inorganic copper ions could not be used for antibacterial purposes, so the antibacterial properties were poor, but the toughening additive was added, and the mechanical properties and impact toughness were excellent; Comparative Example 2 did not add the toughening additive, and the toughening additive could not be used to form a polymer network with the polyvinyl chloride matrix, so the impact toughness and mechanical properties were poor, but the composite antibacterial component was added, so the antibacterial properties were excellent; Comparative Example 3 added o-vanillin, which was easy to precipitate and migrate, resulting in a decrease in antibacterial properties, but the toughening additive was added, and the mechanical properties and impact toughness were excellent; Comparative Example 4 added bamboo fiber, and the toughening effect and mechanical properties were poor, but the composite antibacterial component was added, and the antibacterial properties were excellent.

[0082] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. An antibacterial masterbatch based on polyvinyl chloride, characterized in that: The invention comprises the following raw materials in parts by weight: 70-85 parts of polyvinyl chloride, 2-6 parts of stabilizer, 3-5 parts of lubricant, 0.5-2 parts of extender, 3-6 parts of composite antibacterial component and 4-8 parts of toughening additive.

2. The polyvinyl chloride-based antibacterial masterbatch according to claim 1, characterized in that: The stabilizer is a calcium zinc stabilizer or a barium zinc stabilizer; the lubricant is polyethylene wax or microcrystalline wax.

3. The polyvinyl chloride-based antibacterial masterbatch according to claim 1, characterized in that: The preparation method of the compatibilizer is as follows: After polyvinyl chloride, maleic anhydride and dipentadienyl vulcanizing agent are uniformly mixed, stirred at a stirring rate of 500-600 r / min for 5-10 minutes, added into a twin-screw extruder, extruded at 200-220° C., granulated and dried to obtain a compatibilizer.

4. The polyvinyl chloride-based antibacterial masterbatch according to claim 1, characterized in that: The preparation method of the composite antibacterial component comprises the following steps: Step A: adding branched polyethyleneimine and o-vanillin to ethanol, stirring evenly, adding ammonia water to adjust the pH, placing the system in a water bath at 50-70° C., stirring for 2-4 hours, separating the product, and obtaining an antibacterial intermediate; Step B: Add the antibacterial intermediate product and CuCl2·2H2O into anhydrous ethanol, mix well, heat under reflux for 3-5 hours, separate the product, wash, and dry to obtain a composite antibacterial component.

5. The polyvinyl chloride-based antibacterial masterbatch according to claim 4, characterized in that: In step A, the weight average molecular weight of the branched polyethyleneimine is 1800.

6. The polyvinyl chloride-based antibacterial masterbatch according to claim 4, characterized in that: In step A, the pH is 8-9.

7. The polyvinyl chloride-based antibacterial masterbatch according to claim 1, characterized in that: The preparation method of the toughening additive comprises the following steps: S1: adding bamboo fiber into a potassium hydroxide solution with a mass fraction of 8-10%, heating to 40-50°C, stirring for 1-2h, filtering, washing, and drying to obtain alkali-treated bamboo fiber; S2: dispersing the alkali-treated bamboo fiber in acetone, adding 3-mercaptopropionic acid and a catalyst, stirring evenly, heating under reflux for 2-4 hours, filtering, washing, and drying to obtain thiolated bamboo fiber; S3: Disperse the thiolated bamboo fiber in N,N-dimethylformamide, add eucommia gum and photoinitiator, stir evenly, irradiate under ultraviolet light at room temperature for 6-8 hours, filter, wash and dry to obtain a toughening additive.

8. The polyvinyl chloride-based antibacterial masterbatch according to claim 7, characterized in that: In S2, the catalyst is dicyclohexylcarbodiimide and 4-dimethylaminopyridine in a mass ratio of 6-7:2-3.

9. The polyvinyl chloride-based antibacterial masterbatch according to claim 7, characterized in that: In S3, the photoinitiator is benzoin dimethyl ether or benzoin isopropyl ether.

10. A method for preparing an antibacterial masterbatch based on polyvinyl chloride as claimed in claim 1, characterized in that: The following steps are involved: Step 1: Add polyvinyl chloride, stabilizer, lubricant, compatibilizer, composite antibacterial component and toughening additive into a high-speed mixer, set the speed to 500-800 r / min, stir and mix for 20-60 minutes to obtain a mixture; Step 2: Add the mixed material into a twin-screw extruder, set the barrel temperature of the twin-screw extruder to 110-130°C, set the head temperature to 120-140°C, extrude and granulate, and cool the mixture to obtain an antibacterial masterbatch.

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