PVC composite material with antibacterial function and preparation method thereof

Abstract

The invention relates to the technical field of composite materials, and discloses a PVC composite material with an antibacterial function and a preparation method thereof.The composite material is prepared by taking polyvinyl chloride as a base material and a bamboo fiber modified material and the like as auxiliary materials through mixing and extrusion granulation processes. Wherein the bamboo fiber modified material is prepared by simultaneously modifying a quaternary ammonium salt cationic antibacterial agent and macromolecular polybutadiene on the surface of bamboo fiber, and the bamboo fiber exists in the composite material in a physical core manner, so that the polyvinyl chloride can be reinforced and toughened; the existence of the quaternary ammonium salt cationic antibacterial agent can endow the composite material with good antibacterial performance, and the bamboo fibers are limited in a cross-linked network, so that a confinement effect can be generated on the antibacterial agent, the problems of migration, precipitation and the like of the antibacterial agent can be avoided, and the long-acting antibacterial performance of the composite material is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and in particular to a PVC composite material with antibacterial functionality and a preparation method thereof. Background Art

[0002] Polyvinyl chloride (PVC) is widely used in a variety of fields, including medicine, construction, packaging, and home appliances, due to its low cost, excellent processing properties, and chemical resistance. PVC's application in the medical field is particularly prominent. According to statistics, the use of medical PVC products, such as blood storage bags, blood catheters, and cardiac catheters, accounts for over 25% of all medical plastics. These products come into direct contact with human blood or body fluids, and if bacteria grow on the surface of the material, it will seriously threaten patient safety. However, the PVC molecular chain contains highly polar chlorine atoms, which have strong intermolecular forces and easily form microporous structures on the surface of its products, creating conditions for bacterial attachment. Furthermore, during the processing of PVC, additives such as plasticizers and stabilizers are often added. These additives may migrate to the material surface, further promoting bacterial growth. Therefore, antimicrobial modification of PVC to impart sustained and stable antimicrobial properties has become an important research direction in materials science.

[0003] Prior art generally involves adding antimicrobial agents to polyvinyl chloride (PVC) for blending and modification, such as quaternary ammonium salt-based organic antimicrobial agents and nanosilver-based inorganic antimicrobial agents. However, quaternary ammonium salt-based organic antimicrobial agents have drawbacks such as poor heat resistance and easy precipitation and migration, while nanosilver-based inorganic antimicrobial agents themselves contain heavy metals and are prone to heavy metal contamination upon abandonment. Based on these issues, the present invention provides a PVC composite material with excellent long-term antimicrobial properties, which can address the problems existing in the prior art. Summary of the Invention

[0004] In order to solve the problems mentioned in the background technology, the purpose of the present invention is to provide a PVC composite material with antibacterial functionality and a preparation method thereof.

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

[0006] A PVC composite material with antibacterial functionality, comprising the following raw materials measured in parts by weight:

[0007]

[0008] The bamboo fiber modified material is prepared by modifying the surface of bamboo fiber with a macromolecular polymer.

[0009] As a further solution of the present invention, the preparation method of the modified bamboo fiber material is as follows:

[0010] Step 1: adding the alkali-treated bamboo fiber to a methanol aqueous solution, and after uniform dispersion, continuing to add a glycidyl silane coupling agent, after the addition is complete, using acetic acid to adjust the pH value of the solution to 4-5, then raising the temperature to 60-70°C, keeping the temperature and stirring for 4-8 hours, cooling and discharging the material to obtain epoxy-modified bamboo fiber;

[0011] Step 2: Disperse the epoxy-modified bamboo fiber in an anhydrous ethanol medium to form a uniform dispersion, then add the quaternary ammonium salt derivative and the phase transfer catalyst to the dispersion, stir evenly, heat to 60-70°C, keep stirring for 6-9 hours, and then continue to add the terminated epoxy polybutadiene. After the addition is completed, continue stirring for 8-12 hours, stop heating, cool and discharge the material to obtain the bamboo fiber modified material.

[0012] As a further solution of the present invention, the volume fraction of the methanol is 60-70%.

[0013] As a further embodiment of the present invention, the glycidyl silane coupling agent is 3-glycidyloxypropyltrimethoxysilane or 3-glycidyloxypropyltriethoxysilane.

[0014] As a further embodiment of the present invention, the alkali treatment method is:

[0015] The bamboo fiber is added to a sodium hydroxide aqueous solution with a mass fraction of 10-30%, soaked at 70-80° C. for 3-6 hours, cooled and discharged, washed with pure water until neutral, and then vacuum dried.

[0016] As a further embodiment of the present invention, the preparation method of the quaternary ammonium salt derivative is as follows:

[0017] Allyltrimethylammonium chloride and mercaptosuccinic acid are added to anhydrous ethanol, stirred and mixed, and then a photoinitiator is added. After the addition is completed, nitrogen is passed through to expel oxygen. After the reaction is carried out under ultraviolet light irradiation for 2-4 hours, the solvent is evaporated and purified to obtain a quaternary ammonium salt derivative.

[0018] As a further embodiment of the present invention, the phase transfer catalyst is any one of tetramethylammonium chloride, tetrabutylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide or tetrabutylammonium hydrogen sulfate.

[0019] As a further embodiment of the present invention, the epoxy value of the epoxy-terminated polybutadiene is 0.4-0.65 mmol / g.

[0020] In the above technical solution, the bamboo fiber is first treated with alkali to fully expose the hydroxyl groups on its surface, and then its surface is modified with a glycidyl silane coupling agent to obtain epoxy-modified bamboo fiber. Then, a quaternary ammonium salt derivative is used as a connector, and in the presence of a phase transfer catalyst, the epoxy-modified bamboo fiber is grafted with terminal epoxy polybutadiene to obtain a bamboo fiber whose surface is simultaneously modified with a quaternary ammonium salt cationic antibacterial agent and a high molecular weight polybutadiene, namely, a bamboo fiber modified material.

[0021] The quaternary ammonium salt derivative is prepared with allyltrimethylammonium chloride and mercaptosuccinic acid as reactants. Under the conditions of photoinitiator and ultraviolet light irradiation, the unsaturated alkenyl substituent and the mercapto substituent in each other's structure can undergo a click reaction to prepare the quaternary ammonium salt derivative.

[0022] As a further embodiment of the present invention, the lubricant is polyethylene wax or montan wax; the heat stabilizer is a calcium zinc stabilizer or a barium zinc stabilizer; the antioxidant is at least one of antioxidant 1010, antioxidant 168 or antioxidant 1076; and the plasticizer is at least one of dioctyl phthalate, epoxy octyl soybean oil or di(2-propylheptyl) phthalate.

[0023] A method for preparing a PVC composite material with antibacterial functionality comprises the following steps:

[0024] The first step is to add all the raw materials weighed in parts by weight into a high-speed mixer, control the temperature to 100-110 ° C, the speed to 500-1000 r / min, and mechanically stir and mix for 20-30 minutes to form a premix;

[0025] The second step is to feed the premixed material into the twin-screw extruder through the feeding port, and then undergo the melt extrusion granulation process to obtain the PVC composite material.

[0026] Beneficial effects of the present invention:

[0027] The present invention prepares a bamboo fiber modified material by simultaneously modifying a quaternary ammonium salt cationic antimicrobial agent and a high molecular weight polybutadiene on the surface of bamboo fiber. The presence of the high molecular weight polybutadiene can serve as a transition structure, effectively improving the compatibility between the bamboo fiber and the polyvinyl chloride substrate. Moreover, during the melt extrusion process, the polybutadiene molecular chain can extend to various regions of the polyvinyl chloride substrate, thereby forming a physical cross-linked network with the bamboo fiber as the core. Not only can the reinforcing effect of the bamboo fiber be efficiently utilized, but the toughening effect of the polybutadiene can also be utilized to achieve the strengthening and toughening of polyvinyl chloride. In addition, the presence of the quaternary ammonium salt cationic antimicrobial agent can impart good antimicrobial properties to the composite material. Moreover, since the bamboo fiber is confined in the cross-linked network, a confined effect can be generated on the antimicrobial agent, thereby preventing the antimicrobial agent from migrating and separating out, thereby ensuring the long-lasting antimicrobial properties of the composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 This is the infrared analysis test diagram of quaternary ammonium salt derivatives. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0031] Example 1

[0032] A PVC composite material with antibacterial functionality, comprising the following raw materials measured in parts by weight:

[0033]

[0034] The preparation method of the composite material comprises the following steps:

[0035] The first step is to add all the raw materials weighed according to their weight into a high-speed mixer, control the temperature to 100 ° C, the speed to 500 r / min, and mechanically stir and mix for 30 minutes to form a premix;

[0036] In the second step, the premixed material is fed into the twin-screw extruder through the feeding port, and the temperature of each zone is controlled in sequence: 170℃ for zone 1, 180℃ for zone 2, 200℃ for zone 3, 210℃ for zone 4, and 220℃ for zone 5. After the melt extrusion granulation process, the PVC composite material can be obtained.

[0037] Example 2

[0038] A PVC composite material with antibacterial functionality, comprising the following raw materials measured in parts by weight:

[0039]

[0040]

[0041] The preparation method of the composite material comprises the following steps:

[0042] The first step is to add all the raw materials weighed according to their weight into a high-speed mixer, control the temperature to 100 ° C, the speed to 800 r / min, and mechanically stir and mix for 30 minutes to form a premix;

[0043] In the second step, the premixed material is fed into the twin-screw extruder through the feeding port, and the temperature of each zone is controlled in sequence: 170℃ for zone 1, 180℃ for zone 2, 200℃ for zone 3, 210℃ for zone 4, and 220℃ for zone 5. After the melt extrusion granulation process, the PVC composite material can be obtained.

[0044] Example 3

[0045] A PVC composite material with antibacterial functionality, comprising the following raw materials measured in parts by weight:

[0046]

[0047] The preparation method of the composite material comprises the following steps:

[0048] The first step is to add all the raw materials weighed according to their weight into a high-speed mixer, control the temperature to 110°C, the speed to 1000r / min, and mechanically stir and mix for 20 minutes to form a premix;

[0049] In the second step, the premixed material is fed into the twin-screw extruder through the feeding port, and the temperature of each zone is controlled in sequence: 170℃ for zone 1, 180℃ for zone 2, 200℃ for zone 3, 210℃ for zone 4, and 220℃ for zone 5. After the melt extrusion granulation process, the PVC composite material can be obtained.

[0050] The modified bamboo fiber material of the above embodiment is prepared by the following method:

[0051] Step S1: add 10g of bamboo fiber to a 20% by mass sodium hydroxide aqueous solution, soak at 75°C for 4h, cool and discharge, wash with pure water until neutral, and then vacuum dry.

[0052] Step S2, adding 6 g of alkali-treated bamboo fiber to a 70% by volume methanol aqueous solution, and after uniform dispersion, adding 2.5 g of 3-glycidyloxypropyltriethoxysilane. After the addition is complete, the pH value of the solution is adjusted to 5 with acetic acid, and then the temperature is raised to 65° C., stirred at this temperature for 6 hours, and then cooled and discharged to obtain epoxy-modified bamboo fiber;

[0053] Step S3, dispersing 3.4g of epoxy-modified bamboo fiber in an anhydrous ethanol medium to form a uniform dispersion, then adding 0.9h of quaternary ammonium salt derivative and tetrabutylammonium bromide to the dispersion, stirring evenly, heating to 65°C, keeping warm and stirring for 8h, and then adding 2.5g of terminal epoxy polybutadiene with an epoxy value of 0.4mmol / g. After the addition is completed, stirring is continued for 92h, heating is stopped, and the temperature is lowered and the material is discharged to obtain a modified bamboo fiber material.

[0054] The preparation method of the quaternary ammonium salt derivative is as follows:

[0055] 0.5 g of allyltrimethylammonium chloride and mercaptosuccinic acid were added to anhydrous ethanol, stirred and mixed, and then a photoinitiator was added. After the addition was completed, nitrogen was passed through to expel oxygen. After the reaction was carried out under ultraviolet light for 3 hours, the solvent was evaporated and purified to obtain a quaternary ammonium salt derivative.

[0056] Figure 1 This is the infrared analysis test chart of the quaternary ammonium salt derivative, where 2800-3000cm -1 The characteristic absorption peaks appearing at 1721 cm are the CH characteristic absorption peaks of methyl and methylene. -1 The characteristic absorption peak at 1189 cm is the C=O characteristic absorption peak of the carboxyl group. -1 The characteristic absorption peak appearing at is the CS characteristic absorption peak.

[0057] Comparative Example 1

[0058] A PVC composite material with antibacterial functionality, comprising the following raw materials measured in parts by weight:

[0059]

[0060] The preparation method of the composite material comprises the following steps:

[0061] The first step is to add all the raw materials weighed according to their weight into a high-speed mixer, control the temperature to 100 ° C, the speed to 800 r / min, and mechanically stir and mix for 30 minutes to form a premix;

[0062] In the second step, the premixed material is fed into the twin-screw extruder through the feeding port, and the temperature of each zone is controlled in sequence: 170℃ for zone 1, 180℃ for zone 2, 200℃ for zone 3, 210℃ for zone 4, and 220℃ for zone 5. After the melt extrusion granulation process, the PVC composite material can be obtained.

[0063] Comparative Example 2

[0064] A PVC composite material with antibacterial functionality, comprising the following raw materials measured in parts by weight:

[0065]

[0066] The preparation method of the composite material comprises the following steps:

[0067] The first step is to add all the raw materials weighed according to their weight into a high-speed mixer, control the temperature to 100 ° C, the speed to 800 r / min, and mechanically stir and mix for 30 minutes to form a premix;

[0068] In the second step, the premixed material is fed into the twin-screw extruder through the feeding port, and the temperature of each zone is controlled in sequence: 170℃ for zone 1, 180℃ for zone 2, 200℃ for zone 3, 210℃ for zone 4, and 220℃ for zone 5. After the melt extrusion granulation process, the PVC composite material can be obtained.

[0069] Performance Testing

[0070] The composite materials in the examples and comparative examples were made into test specimens and subjected to corresponding tests:

[0071] According to the standard GB / T 1040.1-2018, the tensile performance test was carried out and the tensile rate was set to 100 mm / min;

[0072] According to the standard GB / T 31402-2015, the antibacterial performance test was carried out, and Staphylococcus aureus was selected as the test strain;

[0073] The test results are shown in the table below:

[0074] Tensile strength / MPa Elongation at break / % Antibacterial rate / % Example 1 54.8 312 99.9 Example 2 55.3 315 99.9 Example 3 55.0 313 99.9 Comparative Example 1 50.1 267 61.6 Comparative Example 2 40.9 239 61.2

[0075] According to the analysis of the test results, it can be seen that the performance of the materials produced by directly using bamboo fiber as an additive will decrease. This is because the unmodified bamboo fiber cannot produce good compatibility with polyvinyl chloride, is difficult to exist in the core form, and cannot utilize the toughening effect of polybutadiene and the antibacterial effect of allyltrimethylammonium chloride.

[0076] Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas, including the best mode, and also enable any technician in the field to practice the present invention, including making and using any device or system, and implementing any combined method. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements similar to the literal description of the claims, or if they include equivalent structural elements that are not substantially different from the literal description of the claims, then these other embodiments should also be included in the scope of the claims.

[0077] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A PVC composite material with antibacterial functionality, characterized in that: The following raw materials are included in parts by weight: The bamboo fiber modified material is prepared by using a quaternary ammonium salt derivative as a connector to graft terminal epoxy polybutadiene onto the surface of the bamboo fiber for modification.

2. The PVC composite material with antibacterial functionality according to claim 1, characterized in that: The preparation method of the modified bamboo fiber material is as follows: Step 1: Modifying the alkali-treated bamboo fiber using a glycidyl silane coupling agent in a methanol solution medium to obtain epoxy-modified bamboo fiber; Step 2: In an anhydrous ethanol medium, using a quaternary ammonium salt derivative as a linker and catalyzing with a phase transfer catalyst, the epoxy-modified bamboo fiber and the epoxy-terminated polybutadiene are chemically connected to obtain a bamboo fiber modified material.

3. The PVC composite material with antibacterial functionality according to claim 2, characterized in that: The volume fraction of the methanol is 60-70%.

4. The PVC composite material with antibacterial functionality according to claim 2, characterized in that: The glycidyl silane coupling agent is 3-glycidyloxypropyltrimethoxysilane or 3-glycidyloxypropyltriethoxysilane.

5. The PVC composite material with antibacterial functionality according to claim 2, characterized in that: The method of the alkali treatment is: The bamboo fiber is added to a sodium hydroxide aqueous solution with a mass fraction of 10-30%, soaked at 70-80° C. for 3-6 hours, cooled and discharged, washed with pure water until neutral, and then vacuum dried.

6. The PVC composite material with antibacterial functionality according to claim 2, characterized in that: The quaternary ammonium salt derivative is prepared by using allyltrimethylammonium chloride and mercaptosuccinic acid as raw materials and undergoing a click reaction under the action of a photoinitiator.

7. The PVC composite material with antibacterial functionality according to claim 2, characterized in that: The phase transfer catalyst is any one of tetramethylammonium chloride, tetrabutylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide or tetrabutylammonium hydrogen sulfate.

8. The PVC composite material with antibacterial functionality according to claim 2, characterized in that: The epoxy value of the epoxy-terminated polybutadiene is 0.4-0.65 mmol / g.

9. The PVC composite material with antibacterial functionality according to claim 1, characterized in that: The lubricant is polyethylene wax or montan wax; the heat stabilizer is calcium zinc stabilizer or barium zinc stabilizer; the antioxidant is at least one of antioxidant 1010, antioxidant 168 or antioxidant 1076; and the plasticizer is at least one of dioctyl phthalate, epoxy octyl soybean oil or di(2-propylheptyl) phthalate.

10. A method for preparing a PVC composite material with antibacterial functionality according to claim 1, characterized in that: The following steps are involved: The first step is to add all the raw materials weighed in parts by weight into a high-speed mixer, control the temperature to 100-110 ° C, the speed to 500-1000 r / min, and mechanically stir and mix for 20-30 minutes to form a premix; The second step is to feed the premixed material into the twin-screw extruder through the feeding port, and then undergo the melt extrusion granulation process to obtain the PVC composite material.

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