PPR antibacterial pipeline and preparation method thereof

Abstract

The invention relates to a PPR antibacterial pipeline and a preparation method thereof, and belongs to the technical field of pipeline processing. The sea-buckthorn extract is used as an auxiliary medium, green synthesis of the silver nanoparticles can be promoted, use of traditional toxic reducing agents and stabilizing agents is avoided, natural active ingredients contained in the sea-buckthorn extract and the silver nanoparticles generate a synergistic effect, the antibacterial efficiency is remarkably enhanced, and the dosage and biotoxicity of the silver nanoparticles are reduced. Meanwhile, the nano silicon dioxide is added, so that the coating can be kept stable in a high-temperature environment. The carboxymethyl chitosan endows the pipeline with excellent antibacterial performance, and forms a synergistic effect with the silver nanoparticles, so that the antibacterial ability of the pipeline is further enhanced. Through the modification of the silane coupling agent KH560, the interface bonding force between the nano silicon dioxide and carboxymethyl chitosan and the interface bonding force between the nano silicon dioxide and the main component PPR of the pipeline are enhanced, so that the reinforcing agent can be more uniformly and stably dispersed in a PPR matrix, and the overall performance of the pipeline is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of pipeline processing and relates to a PPR antibacterial pipeline and a preparation method thereof. Background Art

[0002] PPR (random copolymer polypropylene) pipes have been widely used in water supply and drainage systems due to their good physical properties, chemical stability and processing performance. However, traditional PPR pipes are prone to deformation in high temperature environments, affecting the use effect. At the same time, as people's requirements for hygiene and health increase, higher requirements are also placed on the antibacterial properties of pipe materials. Therefore, the important direction of industry development is mainly to improve the antibacterial properties of pipes by improving material formulations, optimizing preparation processes, etc., while maintaining their good physical properties and chemical stability to meet the use needs of different fields.

[0003] Silver nanoparticles are widely used in textiles, medical equipment, building materials, and environmental pollution control due to their unique physical, chemical, and biological properties and excellent antibacterial properties. However, conventional chemical methods often use organic solvents and toxic reducing agents to synthesize silver nanoparticles. These chemicals may have a negative impact on the environment and may pose a potential threat to human, animal, and plant health. In addition, the prepared silver nanoparticles tend to agglomerate over time, and additional stabilizers are required to stabilize the silver nanoparticles and prevent them from agglomerating. Finding a suitable method for preparing silver nanoparticles and using them in PPR pipes has good application potential. Summary of the invention

[0004] The object of the present invention is to provide a PPR antibacterial pipe and a preparation method thereof, which has the characteristics of good antibacterial performance.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A PPR antibacterial pipe comprises an outer layer and an inner layer, wherein the inner layer has the following formula, in parts by weight: 100-110 parts of PPR, 5-10 parts of reinforcing agent, 3-5 parts of antibacterial agent, The preparation method of the antibacterial agent is as follows: S1-1: 5-10 parts by weight of seabuckthorn extract was added to 10-20 parts by weight of deionized water, stirred at 70°C for 2 hours, cooled naturally and filtered to obtain solution A; S1-2: 15 to 20 parts by weight of silver nitrate solution is slowly added to solution A under stirring conditions at 750 to 850 r / min. After the addition is completed, the bottle mouth is sealed with a polyethylene film, and the solution is placed in a constant temperature water bath at 60 to 70 °C for heating and stirring for 1.5 h. The solution is washed with deionized water and the precipitate is collected by centrifugation, and then freeze-dried in a freeze dryer for 6 h to obtain the antibacterial agent.

[0006] Furthermore, the concentration of the silver nitrate solution in S1-2 is 0.2 M.

[0007] Furthermore, in S1-2, the centrifugal speed is 4000-5000 r / min, and the centrifugal time is 5 min.

[0008] Furthermore, the outer layer component is PPR.

[0009] Furthermore, the preparation method of the enhancer is as follows: S5-1: Add 2-3 parts by weight of carboxymethyl chitosan to 80-90 parts by weight of 1 mM acetic acid solution, stir at 50 °C for 1.5-2 h, add silane coupling agent KH560, mix and stir for 1 h, and then place in a refrigerator at 4 °C for 12 h to obtain solution B; S5-2: 8 to 15 parts by weight of nano-silicon dioxide are added to solution B, stirred at 60° C. for 2 to 3 h, washed and filtered with deionized water, and then freeze-dried in a freeze dryer to obtain the enhancer.

[0010] Furthermore, the addition amount of the silane coupling agent KH560 in the S5-1 is 0.5~1 wt%.

[0011] Furthermore, the freeze-drying time in S5-2 is 6 to 8 h.

[0012] A method for preparing a PPR antibacterial pipe, the specific steps of the preparation method are as follows: S8-1: PPR, reinforcing agent and antimicrobial agent are mixed and stirred according to the formula, extruded and granulated to obtain inner layer masterbatch; S8-2: The inner layer masterbatch is put into an extruder for extrusion to obtain the inner layer of the pipe. After natural cooling, the PPR is melted and attached to the surface of the inner layer of the pipe. Subsequently, the pipe is heat-insulated at a temperature of 110-120°C and then cooled to room temperature to obtain the PPR antibacterial pipe.

[0013] Furthermore, the temperature of the extrusion granulation in S8-1 is 160-180°C.

[0014] Furthermore, the insulation time in S8-2 is 30 to 40 min.

[0015] Seabuckthorn extract contains abundant natural polysaccharides. Under suitable conditions, functional groups such as hydroxyl groups in polysaccharide molecules show reducing properties, that is, they can give out electrons or hydrogen ions, thereby undergoing redox reactions with other substances. When seabuckthorn extract is used as a reducing agent, its polysaccharide molecules will react with silver ions. The electrons or hydrogen ions given by the polysaccharide molecules will combine with the silver ions to reduce the silver ions to silver atoms. As the reaction proceeds, the silver atoms will gradually aggregate and form silver nanoparticles. Seabuckthorn extract can not only act as a reducing agent to promote the synthesis of silver nanoparticles, but also act as a stabilizer to ensure that the formation process of silver nanoparticles is stable and controllable. This characteristic makes it possible to avoid the use of traditional toxic reducing agents and chemical stabilizers when preparing silver nanoparticles, thereby reducing environmental pollution and biosafety risks at the source. In addition, seabuckthorn extract is rich in flavonoids, phenolic acids, organic acids and other natural active ingredients with antibacterial and antioxidant properties. When seabuckthorn extract is used to prepare silver nanoparticles, the seabuckthorn extract will adhere to the silver nanoparticles and produce a synergistic effect. Silver nanoparticles can quickly release silver ions and combine with negative charges on bacterial cell membranes, destroying the integrity of cell membranes and causing leakage of bacterial intracellular substances; at the same time, the active ingredients in silver ion seabuckthorn extracts can also enter the interior of bacteria, combine with intracellular nucleic acids and enzymes and other biological molecules, and interfere with their normal functions. Flavonoids and phenolic acid compounds in seabuckthorn extracts also have significant antibacterial activity, which can further destroy bacterial cell walls and cell membranes through synergistic silver, interfere with their metabolic processes, or inhibit the synthesis of their genetic material. In addition, compared with traditional antibiotics, seabuckthorn extracts and silver nanoparticles are not easy to cause bacterial resistance and have broad application prospects. This synergistic effect not only significantly enhances the antibacterial efficacy of the system, but also effectively reduces the required dose of silver nanoparticles by optimizing the utilization efficiency of silver nanoparticles; the active ingredients in seabuckthorn extracts adhere to the surface of silver nanoparticles to form a protective layer to prevent the shedding and leakage of silver nanoparticles, thereby greatly reducing the biological toxicity that may be caused by silver nanoparticles. Therefore, using seabuckthorn extract as an auxiliary medium to synthesize silver nanoparticles not only realizes a green and environmentally friendly preparation process, but also promotes the dual improvement of the biosafety and application efficacy of antibacterial materials.

[0016] The addition of nano-silica enables it to maintain stable performance under high temperature environment; and carboxymethyl chitosan, as a natural polymer antibacterial agent, can give the pipeline excellent antibacterial properties. In addition, carboxymethyl chitosan and silver nanoparticle antibacterial agents form a further synergistic effect. Chitosan can preferentially destroy bacterial cell walls and cell membranes, making bacteria more vulnerable to attack by silver ions; silver ions can also inhibit and kill bacteria by interfering with the growth cycle of bacteria and destroying the metabolic process of bacteria. The carboxymethyl chitosan is loaded on nano-silica to prepare a reinforcing agent. The addition of silane coupling agent KH560 can significantly improve the interfacial bonding force between nano-silica and carboxymethyl chitosan and the main component of the pipeline PPR, so that the reinforcing agent can be more evenly and stably dispersed in the PPR matrix, thereby improving the overall performance of the pipeline. Freeze-drying can remove moisture from the reinforcing agent and maintain its loose and porous structure, which is conducive to subsequent mixing and processing with PPR materials, and also helps to improve the performance of the pipeline in terms of antibacterial and mechanical properties.

[0017] Beneficial effects of the present invention: (1) The use of seabuckthorn extract as a reducing agent and stabilizer for silver nanoparticles avoids the use of traditional toxic reducing agents and chemical stabilizers, reducing environmental pollution and biosafety risks; at the same time, the natural active ingredients in seabuckthorn extract produce a synergistic effect with silver nanoparticles, significantly enhancing the antibacterial efficacy of the system and reducing the dosage and biological toxicity of silver nanoparticles; the antibacterial effect of seabuckthorn extract and silver nanoparticles is not likely to cause bacterial resistance and has broad application prospects; this synergistic effect not only improves the antibacterial effect, but also enhances the biosafety and practical application effectiveness of antibacterial materials by optimizing the utilization efficiency of silver nanoparticles.

[0018] (2) The addition of nano-silica enables the pipeline to maintain stable performance in a high temperature environment, while carboxymethyl chitosan, as a natural polymer antibacterial agent, gives the pipeline excellent antibacterial properties. The synergistic effect of the two further enhances the antibacterial properties of the pipeline. The addition of silane coupling agent KH560 improves the interfacial bonding force between nano-silica, carboxymethyl chitosan and the main components of the pipeline, allowing the enhancer to be more evenly and stably dispersed in the pipeline matrix. At the same time, the freeze-drying treatment maintains the loose porous structure of the enhancer, which is conducive to the subsequent mixing and processing with the pipeline material, further improving the overall performance of the pipeline in terms of antibacterial and mechanical properties. DETAILED DESCRIPTION

[0019] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0020] In the following examples and comparative examples: PPR: purchased from Chengdu Dianchun Technology Co., Ltd.; Sea buckthorn extract: purchased from Shaanxi New Horizon Biotechnology Co., Ltd.; Silver nitrate: purchased from Shanghai MacLean Biochemical Technology Co., Ltd., CAS No. 7761-88-8; Carboxymethyl chitosan: purchased from Xi'an Rongbai Biotechnology Co., Ltd., CAS No. 83512-85-0; Acetic acid: purchased from Shanghai Denuo Chemical Co., Ltd., CAS No. 64-19-7; Silane coupling agent KH560: purchased from Nanjing Hengqiao Chemical Technology Materials Co., Ltd., CAS No. 2530-83-8; Nano-silicon dioxide: purchased from Shanghai Haohong Biopharmaceutical Technology Co., Ltd., CAS number is 60676-86-0.

[0021] Example 1

[0022] A PPR antibacterial pipe, wherein the inner layer formula is as follows, by weight, PPR 105 parts, reinforcing agent 7 parts, antibacterial agent 4 parts, The preparation method of the antibacterial agent is as follows: S1-1: 7.5 parts by weight of seabuckthorn extract was added to 15 parts by weight of deionized water, stirred at 70°C for 2 h, cooled naturally and filtered to obtain solution A; S1-2: 17 parts by weight of 0.2 M silver nitrate solution was slowly added to solution A under stirring at 800 r / min. After the addition was completed, the bottle mouth was sealed with a polyethylene film, and the solution was placed in a 65°C constant temperature water bath for heating and stirring for 1.5 h. The solution was washed with deionized water and collected by centrifugation at a centrifugal speed of 4500 r / min and a centrifugal time of 5 min. The solution was placed in a freeze dryer and freeze-dried for 6 h to obtain the antibacterial agent.

[0023] Wherein, the preparation method of the enhancer is as follows: S5-1: 2.5 parts by weight of carboxymethyl chitosan was added to 85 parts by weight of 1 mM acetic acid solution, stirred at 50 °C for 2 h, 0.7 wt% of silane coupling agent KH560 was added, mixed and stirred for 1 h, and then placed in a refrigerator at 4 °C for 12 h to obtain solution B; S5-2: 12 parts by weight of nano-silicon dioxide was added to solution B, stirred at 60° C. for 2.5 h, washed and filtered with deionized water, and then freeze-dried in a freeze dryer for 7 h to obtain the enhancer.

[0024] A method for preparing a PPR antibacterial pipe, the specific steps of the preparation method are as follows: S8-1: PPR, reinforcing agent and antibacterial agent are mixed and stirred according to the formula, the temperature is controlled at 170°C, and extruded and granulated to obtain inner layer masterbatch; S8-2: The inner layer masterbatch is put into an extruder for extrusion to obtain the inner layer of the pipe. After natural cooling, the PPR is melted and attached to the surface of the inner layer of the pipe. Subsequently, the pipe is heat-insulated at 115°C for 35 minutes. After cooling to room temperature, the PPR antibacterial pipe is obtained.

[0025] Example 2

[0026] A PPR antibacterial pipe, wherein the inner layer formula is as follows, by weight, 100 parts of PPR, 5 parts of reinforcing agent, 3 parts of antibacterial agent, The preparation method of the antibacterial agent is as follows: S1-1: 5 parts by weight of seabuckthorn extract was added to 10 parts by weight of deionized water, stirred at 70°C for 2 h, cooled naturally and filtered to obtain solution A; S1-2: 15 parts by weight of 0.2 M silver nitrate solution are slowly added to solution A under stirring at 750 r / min. After the addition is completed, the bottle mouth is sealed with a polyethylene film, and the solution is placed in a 60°C constant temperature water bath for heating and stirring for 1.5 h. The solution is washed with deionized water and collected by centrifugation at a centrifugal speed of 4000 r / min and a centrifugal time of 5 min. The solution is placed in a freeze dryer and freeze-dried for 6 h to obtain the antibacterial agent.

[0027] Wherein, the preparation method of the enhancer is as follows: S5-1: 2 parts by weight of carboxymethyl chitosan was added to 80 parts by weight of 1 mM acetic acid solution, stirred at 50 °C for 1.5 h, 0.5 wt% of silane coupling agent KH560 was added, mixed and stirred for 1 h, and then placed in a refrigerator at 4 °C for 12 h to obtain solution B; S5-2: 8 parts by weight of nano-silicon dioxide was added to solution B, stirred at 60° C. for 2 h, washed and filtered with deionized water, and then freeze-dried in a freeze dryer for 6 h to obtain the enhancer.

[0028] A method for preparing a PPR antibacterial pipe, the specific steps of the preparation method are as follows: S8-1: PPR, reinforcing agent and antibacterial agent are mixed and stirred according to the formula, the temperature is controlled at 160°C, and extruded and granulated to obtain inner layer masterbatch; S8-2: The inner layer masterbatch is put into an extruder for extrusion to obtain the inner layer of the pipe. After natural cooling, the PPR is melted and attached to the surface of the inner layer of the pipe. Subsequently, the pipe is heat-insulated at 110°C for 30 minutes. After cooling to room temperature, the PPR antibacterial pipe is obtained.

[0029] Example 3

[0030] A PPR antibacterial pipe, wherein the inner layer formula is as follows, by weight, PPR 110 parts, reinforcing agent 10 parts, antibacterial agent 5 parts, The preparation method of the antibacterial agent is as follows: S1-1: 10 parts by weight of seabuckthorn extract was added to 20 parts by weight of deionized water, stirred at 70°C for 2 h, cooled naturally and filtered to obtain solution A; S1-2: Slowly add 20 parts by weight of 0.2 M silver nitrate solution to solution A under stirring at 850 r / min. After the addition is completed, seal the bottle mouth with a polyethylene film, place it in a 70°C constant temperature water bath and heat and stir for 1.5 h. Wash it with deionized water and collect the precipitate by centrifugation at a centrifugal speed of 5000 r / min and a centrifugal time of 5 min. Place it in a freeze dryer and freeze-dry it for 6 h to obtain the antibacterial agent.

[0031] Wherein, the preparation method of the enhancer is as follows: S5-1: 3 parts by weight of carboxymethyl chitosan was added to 90 parts by weight of 1 mM acetic acid solution, stirred at 50 °C for 2 h, 1 wt% of silane coupling agent KH560 was added, mixed and stirred for 1 h, and then placed in a refrigerator at 4 °C for 12 h to obtain solution B; S5-2: 15 parts by weight of nano-silicon dioxide was added to solution B, stirred at 60° C. for 3 h, washed and filtered with deionized water, and then freeze-dried in a freeze dryer for 8 h to obtain the enhancer.

[0032] A method for preparing a PPR antibacterial pipe, the specific steps of the preparation method are as follows: S8-1: PPR, reinforcing agent and antibacterial agent are mixed and stirred according to the formula, the temperature is controlled at 180°C, and extruded and granulated to obtain inner layer masterbatch; S8-2: The inner layer masterbatch is put into an extruder for extrusion to obtain the inner layer of the pipe. After natural cooling, the PPR is melted and attached to the surface of the inner layer of the pipe. Subsequently, the pipe is heat-insulated at 120°C for 40 minutes. After cooling to room temperature, the PPR antibacterial pipe is obtained.

[0033] Comparative Example 1 Silver nanoparticles reduced by sodium borohydride were used as antibacterial agents, and the remaining steps were consistent with those in Example 1.

[0034] Comparative Example 2 The seabuckthorn extract was used as the antibacterial agent, and the remaining steps were consistent with those in Example 1.

[0035] Comparative Example 3 No antibacterial agent was added, and the remaining steps were consistent with those in Example 1.

[0036] Comparative Example 4 In the preparation of the enhancer, carboxymethyl chitosan was not added, and the remaining steps were the same as those in Example 1.

[0037] The antibacterial PPR pipes prepared in the examples and comparative examples were tested for antibacterial properties according to the QB / T2591-2003 testing method and standard, and Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus were selected as indicator bacteria, respectively.

[0038] The experimental data are summarized in the following table:

[0039] It can be seen from the experimental data of the embodiments and the comparative examples that the antibacterial rates of the embodiments against Escherichia coli and Staphylococcus aureus are significantly better than those of the comparative examples, indicating that the PPR pipe prepared by using seabuckthorn extract to prepare silver nanoparticles as an antibacterial agent and combining carboxymethyl chitosan loaded nanosilica as a reinforcing agent has excellent broad-spectrum antibacterial properties.

[0040] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A PPR antibacterial pipeline, characterized in that: It includes an outer layer and an inner layer, wherein: The inner layer formula is as follows: by weight, PPR 100-110 parts, reinforcing agent 5-10 parts, antibacterial agent 3-5 parts, The preparation method of the antibacterial agent is as follows: S1-1: 5-10 parts by weight of seabuckthorn extract was added to 10-20 parts by weight of deionized water, stirred at 70°C for 2 h, cooled naturally and filtered to obtain solution A; S1-2: 15 to 20 parts by weight of silver nitrate solution is slowly added to solution A under stirring conditions at 750 to 850 r / min. After the addition is completed, the bottle mouth is sealed with a polyethylene film, and the solution is placed in a constant temperature water bath at 60 to 70 °C for heating and stirring for 1.5 h. The solution is washed with deionized water and the precipitate is collected by centrifugation, and then freeze-dried in a freeze dryer for 6 h to obtain the antibacterial agent.

2. A PPR antibacterial pipe according to claim 1, characterized in that: The concentration of the silver nitrate solution in S1-2 is 0.2 M.

3. The PPR antibacterial pipe according to claim 1, characterized in that: In the S1-2, the centrifugal speed is 4000-5000 r / min, and the centrifugal time is 5 min.

4. The PPR antibacterial pipeline according to claim 1, characterized in that: The outer layer component is PPR.

5. The PPR antibacterial pipeline according to claim 1, characterized in that: The preparation method of the enhancer is as follows: S5-1: Add 2-3 parts by weight of carboxymethyl chitosan to 80-90 parts by weight of 1 mM acetic acid solution, stir at 50 °C for 1.5-2 h, add silane coupling agent KH560, mix and stir for 1 h, and then place in a refrigerator at 4 °C for 12 h to obtain solution B; S5-2: 8 to 15 parts by weight of nano-silicon dioxide are added to solution B, stirred at 60° C. for 2 to 3 h, washed and filtered with deionized water, and then freeze-dried in a freeze dryer to obtain the enhancer.

6. The PPR antibacterial pipeline according to claim 5, characterized in that: The added amount of the silane coupling agent KH560 in the S5-1 is 0.5-1 wt%.

7. The PPR antibacterial pipe according to claim 5, characterized in that: The freeze-drying time in S5-2 is 6 to 8 hours.

8. A method for preparing a PPR antibacterial pipe according to any one of claims 1 to 7, characterized in that: The specific steps of the preparation method are as follows: S8-1: PPR, reinforcing agent and antimicrobial agent are mixed and stirred according to the formula, extruded and granulated to obtain inner layer masterbatch; S8-2: The inner layer masterbatch is put into an extruder for extrusion to obtain the inner layer of the pipe. After natural cooling, the PPR is melted and attached to the surface of the inner layer of the pipe. Subsequently, the pipe is heat-insulated at a temperature of 110-120°C and then cooled to room temperature to obtain the PPR antibacterial pipe.

9. The method for preparing a PPR antibacterial pipe according to claim 8, characterized in that: The temperature of the extrusion granulation in S8-1 is 160-180°C.

10. The method for preparing a PPR antibacterial pipe according to claim 8, characterized in that: The insulation time in S8-2 is 30 to 40 minutes.

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