Antibacterial agent, antibacterial PSU composite and method for preparing the same

Abstract

The application discloses an antibacterial agent, an antibacterial PSU composite material and a preparation method of the antibacterial agent, and the preparation method of the antibacterial agent comprises the following steps: placing acrylamide, gallic acid, an initiator, a crosslinking agent, an organic solvent, magnesium chloride and deionized water in a flask, stirring and reacting at 40-60 DEG C for 8-12 hours to prepare product A; filtering, washing and drying the product A to obtain the antibacterial agent. The application synthesizes a new antibacterial agent of the gallic acid / polyacrylamide / Mg 2+ type, the Mg 2+ and the active protease in the bacterial body are combined to lose activity, so that the bacteria are killed, and the antibacterial effect is achieved. The gallic acid can affect the permeability of microbial cells, nucleic acid synthesis and enzyme activity, and finally causes the death of the bacteria.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to an antibacterial agent, an antibacterial PSU composite material, and a method for preparing the same. Background Technology

[0002] Polysulfone (PSU), as a high-performance engineering plastic, has attracted much attention due to its excellent comprehensive properties. Specifically, PSU not only possesses excellent heat resistance, maintaining stable physical and chemical properties at high temperatures, but also exhibits excellent chemical corrosion resistance, resisting the erosion of various corrosive substances. Furthermore, PSU's mechanical properties are equally commendable; its high strength, high toughness, and excellent fatigue resistance allow it to maintain structural integrity and stability even under complex stress environments. Coupled with its good insulation properties, PSU also shows broad application prospects in the electrical field.

[0003] Based on these numerous advantages, PSU has been widely used in the automotive interior and home appliance industries. However, despite its excellent performance in these fields, the insufficient antimicrobial properties of PSU have become a key factor restricting its further expansion. In fields with higher requirements for antimicrobial properties, such as medical, food packaging, and public health facilities, the antimicrobial properties of PSU are clearly insufficient to meet practical needs. Therefore, how to improve the antimicrobial properties of PSU to better adapt to the needs of these special application scenarios has become an important issue that urgently needs to be addressed in the field of materials science.

[0004] It is worth noting that with increasing awareness of health, safety, and environmental protection, the requirements for the antibacterial properties of materials are also becoming more stringent. Therefore, developing PSU materials with excellent antibacterial properties will not only help broaden their application areas but also meet people's pursuit of a high-quality life. (Invention Content)

[0005] In view of this, the present invention provides an antibacterial agent, an antibacterial PSU composite material and a method for preparing the same, to solve the problems mentioned in the background art. The obtained PSU composite material has excellent antibacterial properties, expanding the application fields of PSU composite materials, such as water dispensers, water purifiers, outdoor communication base station equipment, etc. Summary of the Invention

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] The first aspect of this invention discloses a method for preparing an antibacterial agent, comprising the following steps:

[0008] (1) Place acrylamide, gallic acid, initiator, crosslinking agent, organic solvent, magnesium chloride, and deionized water in a flask and stir at 40-60℃ for 8-12 hours to prepare product A.

[0009] (2) Filter, wash and dry product A to obtain the antibacterial agent.

[0010] As a further embodiment of the present invention: the mass ratio of acrylamide, gallic acid, initiator, crosslinking agent, organic solvent, magnesium chloride and deionized water in step (1) is (31.5-40): (28-30): (0.1-0.3): (0.2-0.4): (50-70): (16-20): (80-90).

[0011] As a further aspect of the present invention: the initiator is sodium sulfate, and the crosslinking agent is N,N-methylenebisacrylamide.

[0012] Secondly, the present invention discloses an antibacterial agent prepared by the above-described preparation method.

[0013] Thirdly, this invention discloses an antibacterial PSU composite material, which is composed of the following components in parts by weight:

[0014] 95.5-105.5 parts of PSU resin

[0015] 3-5 parts antibacterial agent

[0016] Antioxidant 0.1-0.5 parts;

[0017] The antibacterial agent used is the antibacterial agent as described in claim 4.

[0018] As a further aspect of the present invention, the antioxidant is at least one of 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester and 4,6-bis(octylthiomethyl)o-cresol.

[0019] Fourthly, this invention discloses a method for preparing the antibacterial PSU composite material as described above, comprising the following steps:

[0020] Weigh out PSU, antibacterial agent, and antioxidant according to the weight proportions, mix and stir evenly to obtain the mixture;

[0021] The mixture is extruded and granulated from a twin-screw extruder to obtain the antibacterial PSU composite material.

[0022] As a further aspect of the present invention: the twin-screw extruder includes six temperature zones arranged in sequence, namely: zone 1 temperature 290~330℃, zone 2 temperature 310~350℃, zone 3 temperature 310~350℃, zone 4 temperature 310~350℃, zone 5 temperature 310~350℃, zone 6 temperature 310~350℃, die head temperature 310~350℃, and screw speed 200~280r / min.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] (1) The reaction mechanism of this antibacterial agent is as follows: Acrylamide polymerizes to form polyacrylamide under the action of sodium persulfate initiator. Gallic acid has a catechol group, which has a considerable ability to coordinate with Mg through metal. 2+ Gallic acid / polyacrylamide / Mg forms a cross-linked network structure with polyacrylamide under the action of the cross-linking agent N,N-methylenebisacrylamide. 2+ This type of hydrogel is an antibacterial agent.

[0025] (2) This invention synthesizes a gallic acid / polyacrylamide / Mg 2+ This type of antibacterial agent has the following antibacterial mechanism: ①Mg 2+ Gallic acid binds to active proteases within bacteria, rendering them inactive and thus killing the bacteria, achieving an antibacterial effect. ② Gallic acid affects the permeability of microbial cells, nucleic acid synthesis, and enzyme activity, ultimately leading to bacterial death. Detailed Implementation

[0026] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0028] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0029] PSU (model P-1710), Solvay, USA; Acrylamide, Jiangxi Changjiu Agricultural Science and Chemical Co., Ltd.

[0030] Gallic acid, Shandong Pingju Biotechnology Co., Ltd.;

[0031] The organic solvent used is acetone, from Shandong Changyuan Chemical Co., Ltd.

[0032] Deionized water, Xiamen Aoquan Environmental Protection Technology Co., Ltd.

[0033] Chitosan, Shandong Pingju Biotechnology Co., Ltd.;

[0034] Sodium persulfate, Shandong Jinli Chemical Co., Ltd.;

[0035] N,N-Methylenebisacrylamide, Shenzhen Boshun Chemical Co., Ltd.;

[0036] Antioxidants (2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl ester, 4,6-bis(octylthiomethyl)o-cresol), BASF.

[0037] All materials are commercially available, commonly used products.

[0038] It is understood that the above-mentioned raw materials and reagents are merely examples of some specific embodiments of the present invention, making the technical solution of the present invention clearer, and do not mean that the present invention can only use the above-mentioned reagents. The specific scope shall be determined by the claims. In addition, unless otherwise specified, "parts" in the examples and comparative examples refer to parts by weight.

[0039] Any range described in this invention includes the endpoint, any value between the endpoints, and any subrange consisting of the endpoint or any value between the endpoints.

[0040] Preparation Example 1

[0041] (1) Weigh 320g acrylamide, 280g gallic acid, 1g sodium persulfate initiator, 2g N,N-methylenebisacrylamide crosslinking agent, 500g acetone, 160g magnesium chloride, and 800g deionized water, place them in a flask, and stir at 40°C for 8 hours to prepare product A.

[0042] (2) Product A was filtered, washed, and dried to obtain gallic acid / polyacrylamide / Mg 2+ The type of hydrogel is the antibacterial agent M1.

[0043] Example 1

[0044] (1) Weigh 95.5 parts of PSU, 3 parts of antibacterial agent M1, and 0.1 parts of β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, mix and stir evenly to obtain a mixture;

[0045] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material P1.

[0046] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 temperature 295℃, zone 2 temperature 325℃, zone 3 temperature 325℃, zone 4 temperature 325℃, zone 5 temperature 325℃, zone 6 temperature 325℃, die head temperature 325℃, and screw speed 200r / min.

[0047] Comparative Example 1

[0048] (1) Weigh 95.5 parts of PSU, 3 parts of commercially available antibacterial agent chitosan, and 0.1 parts of β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionic acid n-octadecyl alcohol ester, mix and stir evenly to obtain a mixture;

[0049] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D1.

[0050] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 temperature 295℃, zone 2 temperature 325℃, zone 3 temperature 325℃, zone 4 temperature 325℃, zone 5 temperature 325℃, zone 6 temperature 325℃, die head temperature 325℃, and screw speed 200r / min.

[0051] Preparation Example 2

[0052] (1) Weigh 400g acrylamide, 300g gallic acid, 3g sodium persulfate initiator, 4g N,N-methylenebisacrylamide crosslinking agent, 700g acetone, 200g magnesium chloride, and 900g deionized water, place them in a flask, and stir at 60°C for 2 hours to prepare product A.

[0053] (2) Product A was filtered, washed, and dried to obtain gallic acid / polyacrylamide / Mg 2+ The type of hydrogel is the antibacterial agent M2.

[0054] Example 2

[0055] (1) Weigh 105.5 parts of PSU, 5 parts of antibacterial agent M2, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, 0.2 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], and 0.2 parts of antioxidant 4,6-bis(octylthiomethyl)o-cresol, mix and stir evenly to obtain a mixture;

[0056] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material P2.

[0057] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (310℃), zone 2 (330℃), zone 3 (330℃), zone 4 (330℃), zone 5 (330℃), zone 6 (330℃), and the die head temperature (330℃). The screw speed is 240 r / min.

[0058] Comparative Example 2

[0059] (1) Weigh 105.5 parts of PSU, 5 parts of commercially available antibacterial agent chitosan, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, 0.2 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], and 0.2 parts of antioxidant 4,6-bis(octylthiomethyl)o-cresol, mix and stir evenly to obtain a mixture;

[0060] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D2.

[0061] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (310℃), zone 2 (330℃), zone 3 (330℃), zone 4 (330℃), zone 5 (330℃), zone 6 (330℃), and the die head temperature (330℃). The screw speed is 240 r / min.

[0062] Preparation Example 3

[0063] (1) Weigh 360g acrylamide, 290g gallic acid, 2g sodium persulfate initiator, 3g N,N-methylenebisacrylamide crosslinking agent, 600g acetone, 180g magnesium chloride, and 850g deionized water, place them in a flask, and stir the reaction at 50°C for 10h to prepare product A.

[0064] (2) Product A was filtered, washed, and dried to obtain gallic acid / polyacrylamide / Mg 2+ This type of hydrogel is the antibacterial agent M3.

[0065] Example 3

[0066] (1) Weigh 100.5 parts of PSU, 4 parts of antibacterial agent M3, 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], and 0.2 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, mix and stir evenly to obtain a mixture;

[0067] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material P3.

[0068] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (310℃), zone 2 (330℃), zone 3 (330℃), zone 4 (330℃), zone 5 (330℃), zone 6 (330℃), and the die head temperature (330℃). The screw speed is 280 r / min.

[0069] Comparative Example 3

[0070] (1) Weigh 100.5 parts of PSU, 4 parts of commercially available antibacterial agent chitosan, 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], and 0.35 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, mix and stir evenly to obtain a mixture;

[0071] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D3.

[0072] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (310℃), zone 2 (330℃), zone 3 (330℃), zone 4 (330℃), zone 5 (330℃), zone 6 (330℃), and the die head temperature (330℃). The screw speed is 280 r / min.

[0073] Preparation Example 4

[0074] (1) Weigh 315g acrylamide, 298g gallic acid, 1.5g sodium persulfate initiator, 2.5g N,N-methylenebisacrylamide crosslinking agent, 635g acetone, 185g magnesium chloride, and 868g deionized water, place them in a flask, and stir at 48°C for 11.5h to prepare product A.

[0075] (2) Filter, wash and dry product A to obtain gallic acid / polyacrylamide / Mg2+ type hydrogel, which is antibacterial agent M4.

[0076] Example 4

[0077] (1) Weigh 102.5 parts of PSU, 3.5 parts of antibacterial agent M4, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.3 parts of antioxidant 4,6-bis(octylthiomethyl)o-cresol, mix and stir evenly to obtain a mixture;

[0078] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material P4.

[0079] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 temperature 295℃, zone 2 temperature 325℃, zone 3 temperature 325℃, zone 4 temperature 325℃, zone 5 temperature 325℃, zone 6 temperature 325℃, die head temperature 325℃, and screw speed 245r / min.

[0080] Comparative Example 4

[0081] (1) Weigh 102.5 parts of PSU, 3.5 parts of commercially available antibacterial agent chitosan, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.3 parts of antioxidant 4,6-bis(octylthiomethyl)o-cresol, mix and stir evenly to obtain a mixture;

[0082] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D4.

[0083] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 temperature 295℃, zone 2 temperature 325℃, zone 3 temperature 325℃, zone 4 temperature 325℃, zone 5 temperature 325℃, zone 6 temperature 325℃, die head temperature 325℃, and screw speed 245r / min.

[0084] Preparation Example 5

[0085] (1) Weigh 335g acrylamide, 295g gallic acid, 1g sodium persulfate initiator, 2.5g N,N-methylenebisacrylamide crosslinking agent, 555g acetone, 185g magnesium chloride, and 868g deionized water, place them in a flask, and stir at 47°C for 11h to prepare product A.

[0086] (2) Filter, wash and dry product A to obtain a hydrogel of gallic acid / polyacrylamide / Mg2+ type, which is antibacterial agent M5.

[0087] Example 5

[0088] (1) Weigh 97.5 parts of PSU, 3.8 parts of antibacterial agent M5, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], mix and stir evenly to obtain a mixture;

[0089] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material P5.

[0090] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (315℃), zone 2 (335℃), zone 3 (335℃), zone 4 (335℃), zone 5 (335℃), zone 6 (335℃), and the die head temperature (335℃). The screw speed is 265 r / min.

[0091] Comparative Example 5

[0092] (1) Weigh 97.5 parts of PSU, 3.8 parts of commercially available antibacterial agent chitosan, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], mix and stir evenly to obtain a mixture;

[0093] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D5.

[0094] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (315℃), zone 2 (335℃), zone 3 (335℃), zone 4 (335℃), zone 5 (335℃), zone 6 (335℃), and the die head temperature (335℃). The screw speed is 265 r / min.

[0095] Comparative Example 6

[0096] (1) Weigh 97.5 parts of PSU, 3.8 parts of gallic acid, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], mix and stir evenly to obtain a mixture;

[0097] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D6.

[0098] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (315℃), zone 2 (335℃), zone 3 (335℃), zone 4 (335℃), zone 5 (335℃), zone 6 (335℃), and the die head temperature (335℃). The screw speed is 265 r / min.

[0099] Comparative Example 7

[0100] (1) Weigh 97.5 parts of PSU, 3.8 parts of magnesium chloride, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], mix and stir evenly to obtain a mixture;

[0101] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D7.

[0102] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (315℃), zone 2 (335℃), zone 3 (335℃), zone 4 (335℃), zone 5 (335℃), zone 6 (335℃), and the die head temperature (335℃). The screw speed is 265 r / min.

[0103] Comparative Example 8

[0104] (1) Weigh 97.5 parts of PSU, 2.3 parts of gallic acid, 1.5 parts of magnesium chloride, 0.1 parts of antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester, and 0.1 parts of antioxidant 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate ethyl ester], mix and stir evenly to obtain a mixture;

[0105] (2) The mixture obtained in step (1) is extruded from the extruder and granulated to obtain PSU composite material D8.

[0106] The twin-screw extruder includes six temperature zones arranged in sequence: zone 1 (315℃), zone 2 (335℃), zone 3 (335℃), zone 4 (335℃), zone 5 (335℃), zone 6 (335℃), and the die head temperature (335℃). The screw speed is 265 r / min.

[0107] The PSU composite materials prepared in Examples 1-5 and Comparative Examples 1-8 were injection molded into specimens for testing. The test data are shown in Table 1 below.

[0108] Table 1

[0109]

[0110] As can be seen from the table above, the antibacterial properties of Examples 1-5 are better than those of Comparative Examples 1-8.

[0111] This demonstrates that the PSU composite material prepared by the method provided by this invention has good antibacterial properties, which can expand the application fields of PSU composite materials.

[0112] Although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0113] Therefore, the above description is only a preferred embodiment of this application and is not intended to limit the scope of this application; that is, all equivalent modifications made in accordance with the scope of the claims of this application shall be within the protection scope of the claims of this application.

Claims

1. A method for preparing an antibacterial agent, characterized in that, Includes the following steps: (1) Place acrylamide, gallic acid, initiator, crosslinking agent, organic solvent, magnesium chloride, and deionized water in a flask and stir at 40-60℃ for 8-12 hours to prepare product A. (2) Filter, wash and dry product A to obtain the antibacterial agent.

2. The preparation method according to claim 1, characterized in that, The mass ratio of acrylamide, gallic acid, initiator, crosslinking agent, organic solvent, magnesium chloride, and deionized water in step (1) is (31.5-40): (28-30): (0.1-0.3): (0.2-0.4): (50-70): (16-20): (80-90).

3. The preparation method according to claim 1, characterized in that, The initiator is sodium sulfate, and the crosslinking agent is N,N-methylenebisacrylamide.

4. An antibacterial agent prepared by the preparation method according to any one of claims 1-3.

5. An antibacterial PSU composite material, characterized in that, Composed of the following components in parts by weight: 95.5-105.5 parts of PSU resin 3-5 parts antibacterial agent Antioxidant 0.1-0.5 parts; The antibacterial agent used is the antibacterial agent as described in claim 4.

6. The antibacterial PSU composite material according to claim 5, characterized in that, The antioxidant is at least one of 2,2'-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], β-(4-hydroxyphenyl-3,5-di-tert-butyl)propionate n-octadecyl alcohol ester and 4,6-bis(octylthiomethyl)o-cresol.

7. The method for preparing the antibacterial PSU composite material according to any one of claims 5-6, characterized in that, Includes the following steps: Weigh out PSU, antibacterial agent, and antioxidant according to the weight proportions, mix and stir evenly to obtain the mixture; The mixture is extruded and granulated from a twin-screw extruder to obtain the antibacterial PSU composite material.

8. The preparation method according to claim 7, characterized in that, The twin-screw extruder includes six temperature zones arranged in sequence, namely: Zone 1 temperature 290~330℃, Zone 2 temperature 310~350℃, Zone 3 temperature 310~350℃, Zone 4 temperature 310~350℃, Zone 5 temperature 310~350℃, Zone 6 temperature 310~350℃, Die head temperature 310~350℃, and screw speed 200~280r / min.

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