Synthesis method of halamine quaternary ammonium salt antibacterial cellulose membrane

Abstract

The invention relates to the technical field of antibacterial fiber membranes, and discloses a synthesis method of a halamine quaternary ammonium salt antibacterial cellulose membrane, which comprises the following steps: introducing a halamine quaternary ammonium salt antibacterial agent with double antibacterial functions on the surface of cellulose through surface grafting, and preparing the halamine quaternary ammonium salt antibacterial cellulose membrane by using hexamethylene diisocyanate as a cross-linking agent. Hydroxyl of the antibacterial agent is bonded with hydroxyl on the surface of cellulose, so that the halamine quaternary ammonium salt antibacterial agent is fixed on the surface of the fiber, the antibacterial property and the stability of the antibacterial agent are greatly improved, and the problem that the antibacterial agent is easy to lose in the use process is avoided; after multiple times of water washing, active chlorine of quaternary ammonium salt and halamine can still exert the efficient antibacterial effect, and cellulose fiber molecules are tightly combined and are not prone to being damaged due to the crosslinking effect; meanwhile, carboxyl in the molecular structure has a hydrophilic effect and is relatively good in compatibility with cellulose fibers, so that the hydrophilicity and the lasting antibacterial ability of the fiber membrane are further improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of antibacterial fiber membranes, in particular to a synthesis method of a halamine quaternary ammonium salt antibacterial cellulose membrane. BACKGROUND

[0002] Cellulose is a natural polymer resource with the largest reserves in nature, has the characteristics of high polymerization degree, good molecular orientation and strong chemical stability, and cellulose fiber is a natural polymer material with a large output in nature, has the advantages of large specific surface area and biodegradability, and is widely applied to clothing, bedding, bathing supplies and many industrial fields; meanwhile, due to the good hydrophilicity of cellulose fiber, the cellulose fabric is more likely to become a breeding and growing bed for bacteria, and as people's health consciousness improves, the demand for antibacterial and antiviral textiles is increasing; due to the wide application of cellulose products in daily life, the antibacterial durability of cellulose fiber has become a research hotspot.

[0003] At present, the antibacterial method of the fiber is to coat an inorganic antibacterial layer on the outer surface, and the common inorganic antibacterial agent is generally an inorganic compound or metal nanoparticle of metal cations such as silver ions, has the advantages of good heat resistance, long action period and difficulty in producing drug resistance, but faces problems such as environment and human health; meanwhile, the antibacterial layer is easily damaged under the friction condition outside the fiber, the interaction between the fiber and the antibacterial agent is mainly van der Waals force, the interaction is weak, and the antibacterial agent is easy to flow out; in the prior art, the antibacterial agent is arranged on the fiber by methods such as dipping, padding, coating or spraying to obtain antibacterial fiber; the cellulose fiber is treated by dipping with a nano-silver solution to obtain nano-silver antibacterial cellulose fiber; although the antibacterial fiber prepared by this method has certain antibacterial function, the fastness of the antibacterial component in the antibacterial fiber is low, and the antibacterial function is basically lost after several water washes.

[0004] The surface of the cellulose fiber has more hydroxyl groups and is more easily modified than other carrier materials, and the application has the advantages of being more advantageous, the halamine type quaternary ammonium salt antibacterial agent is prepared, the hydroxyl groups on the surface of the cellulose are reacted by chemical grafting, the small-molecule antibacterial agent is fixed on the fiber surface, the dual antibacterial effect of halamine and quaternary ammonium salt is fully exerted, the phenomenon that the antibacterial agent is easy to flow out in the use process is avoided, and the antibacterial durability of the fiber membrane is greatly improved. SUMMARY

[0005] The application aims at overcoming the defects in the prior art, and provides a synthesis method of a halamine quaternary ammonium salt antibacterial cellulose membrane, which avoids the phenomenon that the antibacterial agent is easy to flow out in the use process, and greatly improves the antibacterial property and stability.

[0006] The above object of the application is achieved by the following technical scheme. A method for synthesizing a halamine quaternary ammonium salt antibacterial cellulose membrane, the method being performed according to the following steps: (1) adding cellulose fibers and N, N-dimethylacetamide into a reaction flask, stirring uniformly at a rotation speed of 4000-6000 r / min, adding a halamine carboxylic acid pyridine quaternary ammonium salt intermediate with a structural formula of and hexamethylene diisocyanate, stirring and reacting, after the reaction is completed, casting the solution into a film, defoaming, drying, washing with water and ethanol, and drying to obtain a cellulose membrane containing a halamine pyridine quaternary ammonium salt.

[0007] (2) configuring a sodium hypochlorite aqueous solution, adjusting the pH to neutral with concentrated sulfuric acid, then putting the cellulose membrane containing the halamine pyridine quaternary ammonium salt into the sodium hypochlorite aqueous solution, immersing at 20-35 ℃ for 2-5 h, washing with deionized water, and drying to obtain a halamine quaternary ammonium salt antibacterial cellulose membrane.

[0008] Further, in the step (1), the mass of the halamine carboxylic acid pyridine quaternary ammonium salt intermediate and the hexamethylene diisocyanate is 0.5-5% and 1.2-15% of the mass of the cellulose fibers, respectively.

[0009] Further, in the step (1), the reaction temperature is 60-75 ℃, and the reaction time is 2-4 h.

[0010] Further, in the step (2), the mass fraction of the sodium hypochlorite aqueous solution is 5-10%.

[0011] Further, the method for synthesizing the halamine carboxylic acid pyridine quaternary ammonium salt intermediate in the step (1) is performed according to the following steps: S1, adding isonicotinic acid and acetonitrile into a reaction flask, stirring uniformly, adding epichlorohydrin, stirring and reacting, after the reaction is completed, concentrating under reduced pressure, recrystallizing with ethanol, and obtaining an epoxy carboxylic acid pyridine quaternary ammonium salt intermediate. The preparation process is as follows:

[0012] S2, adding the epoxy carboxylic acid pyridine quaternary ammonium salt intermediate, hydroxyethyl hydantoin, and tetrahydrofuran into a reaction flask, stirring uniformly, then adding potassium hydroxide, reacting at 25-40 ℃ for 5-10 h, adjusting the pH with concentrated hydrochloric acid, concentrating under reduced pressure, recrystallizing with ethanol, and obtaining the halamine carboxylic acid pyridine quaternary ammonium salt intermediate. The preparation process is as follows:

[0013] Further, in the step S1, the mass of the epichlorohydrin is 160-210% of the mass of the isonicotinic acid.

[0014] Further, in the step S1, the reaction temperature is 20-35 ℃, and the reaction time is 18-36 h.

[0015] Further, the mass of the hydroxyethyl hydantoin and the potassium hydroxide in the step S2 is 105-130% and 70-120% of the mass of the pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid respectively.

[0016] Further, the pH is adjusted to 3-5 by using concentrated hydrochloric acid in the step S2.

[0017] By adopting the technical solution, the application has the following beneficial effects: The application first generates a pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid by quaternary ammonization reaction of isonicotinic acid and epichlorohydrin, then reacts the epoxy of the pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid with the hydroxyl of hydroxyethyl hydantoin under the action of potassium hydroxide to obtain a halamine carboxylic acid pyridine quaternary ammonium salt intermediate, then bonds the hydroxyl of the halamine carboxylic acid pyridine quaternary ammonium salt intermediate with the hydroxyl on the surface of cellulose fiber by using hexamethylene diisocyanate as a crosslinking agent, and after casting into a film, obtains a cellulose film containing halamine pyridine quaternary ammonium salt, and finally immerses the cellulose film containing halamine pyridine quaternary ammonium salt in an aqueous sodium hypochlorite solution to obtain a halamine quaternary ammonium salt antibacterial cellulose film with double antibacterial properties.

[0018] The halamine quaternary ammonium salt antibacterial cellulose film contains a pyridine quaternary ammonium salt structure, and the cellulose fiber surface has anions, so the halamine quaternary ammonium salt antibacterial agent can be adsorbed on the surface of the cellulose film by electrostatic adsorption, absorbs bacteria into the internal gap, causes the bacterial biofilm to wrinkle, destroys the cell membrane and causes the death of the bacteria; the halamine quaternary ammonium salt antibacterial cellulose film also contains N-Cl bonds, which can release free strong oxidizing chlorine ions to combine with the amino groups of the proteins on the bacterial cell wall, thereby destroying the structure of the proteins and causing the cell wall of the bacteria to rupture and die, and after the sterilization, the N-Cl bonds are converted into N-H bonds, but after rehalogenation, they become N-Cl bonds again, and have broad-spectrum antibacterial and sterilization regenerability.

[0019] By the method of surface grafting, the quaternary ammonium salt polymer with antibacterial function is introduced on the surface of the cellulose fiber film, the hexamethylene diisocyanate is used as a crosslinking agent to bond the hydroxyl of the small-molecule antibacterial agent with the hydroxyl on the surface of the cellulose, the halamine quaternary ammonium salt antibacterial agent is grafted to the surface of the cellulose, and then the small-molecule antibacterial agent is fixed, the double antibacterial effect of the halamine and the quaternary ammonium salt is fully exerted, the antibacterial property and stability are greatly improved, the loss of the antibacterial agent and the pollution to the surrounding environment are reduced, and the problem that the conventional antibacterial agent is only adsorbed on the surface of the cellulose and is prone to loss during use is avoided.

[0020] The halamine quaternary ammonium salt antibacterial cellulose membrane prepared by the method has strong water washing stability and antibacterial regeneration, and the active chlorine of the quaternary ammonium salt and the halamine can still play the high-efficiency antibacterial effect after multiple water washing, because the crosslinking agent hexamethylene diisocyanate links the hydroxyl groups of the halamine carboxylic acid pyridine quaternary ammonium salt intermediate and the hydroxyl groups of the cellulose fibers, so that the cellulose fiber molecules are combined closely and are not easy to be damaged, meanwhile, the carboxyl groups in the molecular structure have hydrophilic effect and good compatibility with the cellulose fibers, the small-molecule antibacterial agent can be fixed on the fiber surface, and the hydrophilicity and the long-lasting antibacterial capacity of the cellulose membrane are further improved. DETAILED DESCRIPTION

[0021] In order to make the technical means, purposes and effects realized by the present application easy to understand, the present application is further illustrated below in combination with specific examples, but the following examples are only preferred examples of the present application, not all. Based on the examples in the embodiments, other examples obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0022] Example 1 (1) 50 g of isonicotinic acid and acetonitrile were added into a reaction flask, stirred uniformly, 100 g of epichlorohydrin was added, after reaction at 25℃ for 25 h, concentrated under reduced pressure, recrystallized with ethanol to obtain an epoxy carboxylic acid pyridine quaternary ammonium salt intermediate.

[0023] (2) 35 g of the epoxy carboxylic acid pyridine quaternary ammonium salt intermediate, 42 g of hydroxyethyl hydantoin and tetrahydrofuran were added into a reaction flask, stirred uniformly, 38 g of potassium hydroxide was added, reacted at 35℃ for 8 h, the pH was adjusted to 4 with concentrated hydrochloric acid, concentrated under reduced pressure, recrystallized with ethanol to obtain a halamine carboxylic acid pyridine quaternary ammonium salt intermediate.

[0024] (3) 100 g of cellulose fiber and N,N-dimethylacetamide were added into a reaction flask, stirred uniformly at a rotation speed of 5500 r / min, 0.5 g of the halamine carboxylic acid pyridine quaternary ammonium salt intermediate with the structural formula and 1.2 g of hexamethylene diisocyanate were added, reacted at 65℃ for 3 h, then the solution was cast into a film, degassed, dried, washed with water and ethanol, and dried to obtain a cellulose membrane containing halamine pyridine quaternary ammonium salt.

[0025] (4) An 8% sodium hypochlorite aqueous solution was prepared, the pH was adjusted to neutral with concentrated sulfuric acid, then the cellulose membrane containing halamine pyridine quaternary ammonium salt was put into the sodium hypochlorite aqueous solution, immersed at 25℃ for 4 h, washed with deionized water, and dried to obtain a halamine quaternary ammonium salt antibacterial cellulose membrane.

[0026] Example 2 (1) To a reaction flask was added 15 g of isonicotinic acid and acetonitrile, stirred uniformly, 31 g of epichlorohydrin was added, after reaction at 20°C for 18 h, concentrated under reduced pressure, recrystallized with ethanol to obtain the pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid.

[0027] (2) To a reaction flask was added 10 g of the pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid, 13 g of hydroxyethyl hydantoin and tetrahydrofuran, stirred uniformly, 12 g of potassium hydroxide was added, reacted at 25°C for 5 h, adjusted pH to 3 with concentrated hydrochloric acid, concentrated under reduced pressure, recrystallized with ethanol to obtain the pyridine quaternary ammonium salt intermediate of halamine carboxylic acid.

[0028] (3) To a reaction flask was added 100 g of cellulose fiber and N,N-dimethylacetamide, stirred at a rotation speed of 4000 r / min for 5 min, 1.6 g of the pyridine quaternary ammonium salt intermediate of halamine carboxylic acid with the structural formula and 5 g of hexamethylene diisocyanate were added, reacted at 60°C for 2 h, the solution was cast into a film, degassed, dried, washed with water and ethanol, and dried to obtain a halamine pyridine quaternary ammonium salt-containing cellulose film.

[0029] (4) A 5% sodium hypochlorite aqueous solution was prepared, neutralized with concentrated sulfuric acid, and then the halamine pyridine quaternary ammonium salt-containing cellulose film was immersed in the sodium hypochlorite aqueous solution at 20°C for 2 h, washed with deionized water, and dried to obtain a halamine quaternary ammonium salt antibacterial cellulose film.

[0030] Example 3 (1) To a reaction flask was added 40 g of isonicotinic acid and acetonitrile, stirred uniformly, 64 g of epichlorohydrin was added, after reaction at 35°C for 36 h, concentrated under reduced pressure, recrystallized with ethanol to obtain the pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid.

[0031] (2) To a reaction flask was added 25 g of the pyridine quaternary ammonium salt intermediate of epoxy carboxylic acid, 26 g of hydroxyethyl hydantoin and tetrahydrofuran, stirred uniformly, 17 g of potassium hydroxide was added, reacted at 40°C for 10 h, adjusted pH to 5 with concentrated hydrochloric acid, concentrated under reduced pressure, recrystallized with ethanol to obtain the pyridine quaternary ammonium salt intermediate of halamine carboxylic acid.

[0032] (3) To a reaction flask was added 100 g of cellulose fiber and N,N-dimethylacetamide, stirred at a rotation speed of 6000 r / min for 10 min, 2.6 g of the pyridine quaternary ammonium salt intermediate of halamine carboxylic acid with the structural formula and 8 g of hexamethylene diisocyanate were added, reacted at 75°C for 4 h, the solution was cast into a film, degassed, dried, washed with water and ethanol, and dried to obtain a halamine pyridine quaternary ammonium salt-containing cellulose film.

[0033] (4) A 10% sodium hypochlorite aqueous solution is prepared, and the pH is adjusted to neutral with concentrated sulfuric acid. Then, the cellulose membrane containing the halamine pyridine quaternary ammonium salt is put into the sodium hypochlorite aqueous solution, and immersed at 35°C for 5h. After being washed with deionized water and dried, a halamine quaternary ammonium salt antibacterial cellulose membrane is obtained.

[0034] Example 4 (1) A reaction flask is added with 5g isonicotinic acid and acetonitrile, stirred uniformly, and added with 8g epichlorohydrin. After reaction at 30°C for 30h, it is concentrated under reduced pressure, recrystallized with ethanol, and an epoxy carboxylic acid pyridine quaternary ammonium salt intermediate is obtained.

[0035] (2) A reaction flask is added with 3g epoxy carboxylic acid pyridine quaternary ammonium salt intermediate, 3.7g hydroxyethyl hydantoin and tetrahydrofuran, stirred uniformly, and added with 2.7g potassium hydroxide. After reaction at 30°C for 7h, the pH is adjusted to 4 with concentrated hydrochloric acid, concentrated under reduced pressure, recrystallized with ethanol, and a halamine carboxylic acid pyridine quaternary ammonium salt intermediate is obtained.

[0036] (3) A reaction flask is added with 100g cellulose fiber and N,N-dimethylacetamide, stirred at a rotation speed of 4500r / min for 10min, added with 3.8g halamine carboxylic acid pyridine quaternary ammonium salt intermediate with a structural formula of and 11g hexamethylene diisocyanate. After reaction at 65°C for 3h, the solution is cast into a film, degassed, dried, washed with water and ethanol, and dried to obtain a cellulose membrane containing halamine pyridine quaternary ammonium salt.

[0037] (4) A 8% sodium hypochlorite aqueous solution is prepared, and the pH is adjusted to neutral with concentrated sulfuric acid. Then, the cellulose membrane containing the halamine pyridine quaternary ammonium salt is put into the sodium hypochlorite aqueous solution, and immersed at 35°C for 2h. After being washed with deionized water and dried, a halamine quaternary ammonium salt antibacterial cellulose membrane is obtained.

[0038] Example 5 (1) A reaction flask is added with 25g isonicotinic acid and acetonitrile, stirred uniformly, and added with 45g epichlorohydrin. After reaction at 20°C for 36h, it is concentrated under reduced pressure, recrystallized with ethanol, and an epoxy carboxylic acid pyridine quaternary ammonium salt intermediate is obtained.

[0039] (2) A reaction flask is added with 20g epoxy carboxylic acid pyridine quaternary ammonium salt intermediate, 23g hydroxyethyl hydantoin and tetrahydrofuran, stirred uniformly, and added with 16g potassium hydroxide. After reaction at 40°C for 9h, the pH is adjusted to 3 with concentrated hydrochloric acid, concentrated under reduced pressure, recrystallized with ethanol, and a halamine carboxylic acid pyridine quaternary ammonium salt intermediate is obtained.

[0040] (3) A reaction flask is added with 100g cellulose fiber and N,N-dimethylacetamide, stirred at a rotation speed of 6000r / min for 5min, added with 5g halamine carboxylic acid pyridine quaternary ammonium salt intermediate with a structural formula of halamine pyridine quaternary ammonium salt and 15 g of hexamethylene diisocyanate, after reaction at 60°C for 4 h, the solution was cast into a film, deaerated, dried, washed with water and ethanol, and dried to obtain a halamine pyridine quaternary ammonium salt-containing cellulose film.

[0041] (4) An aqueous solution of sodium hypochlorite having a mass fraction of 10% was prepared, and the pH was adjusted to neutral with concentrated sulfuric acid. Then, the halamine pyridine quaternary ammonium salt-containing cellulose film was immersed in the aqueous solution of sodium hypochlorite at 25°C for 45 h, washed with deionized water, and dried to obtain a halamine quaternary ammonium salt antibacterial cellulose film.

[0042] Comparative Example 1 (1) 100 g of cellulose fibers and N,N-dimethylacetamide were added to a reaction flask, and stirred uniformly at a rotation speed of 5500 r / min. Then, 0.5 g of a hydroxyethyl hydantoin intermediate having a structural formula of was added, and 1.2 g of hexamethylene diisocyanate was added, and reacted at 65°C for 3 h. After that, the solution was cast into a film, deaerated, dried, washed with water and ethanol, and dried to obtain a halamine-containing cellulose film.

[0043] (2) An aqueous solution of sodium hypochlorite having a mass fraction of 8% was prepared, and the pH was adjusted to neutral with concentrated sulfuric acid. Then, the halamine-containing cellulose film was immersed in the aqueous solution of sodium hypochlorite at 25°C for 4 h, washed with deionized water, and dried to obtain an antibacterial cellulose film.

[0044] Comparative Example 2 100 g of cellulose fibers and N,N-dimethylacetamide were added to a reaction flask, and stirred uniformly at a rotation speed of 5500 r / min. Then, 0.5 g of an epoxy carboxylic acid pyridine quaternary ammonium salt intermediate having a structural formula of was added, and reacted at 65°C for 5 h. After that, the solution was cast into a film, deaerated, dried, washed with water and ethanol, and dried to obtain a quaternary ammonium salt cellulose film.

[0045] Comparative Example 3 Cellulose fibers and N,N-dimethylacetamide were added to a reaction flask, and stirred uniformly at a rotation speed of 5500 r / min. Then, the solution was cast into a film, deaerated, dried, washed with water and ethanol, and dried to obtain a cellulose film.

[0046] Antibacterial rate test: The test was performed by using a shaking method. The cultured Escherichia coli and Staphylococcus aureus were diluted in a PBS buffer to a bacterial concentration of 2×10 7 -4×10 7The bacteria were diluted to 1.0 x 108cfu / mL, and 0.5 mL of the bacterial solution was added to 4.5 mL of PBS buffer, and 1 mg of the cellulose membrane to be tested (Examples 1-5, Comparative Examples 1-2) was added as the experimental group, and the cellulose membrane of Comparative Example 3 was used as the blank group. The mixture was incubated for 24 h, and then 0.5 mL of the bacterial solution was taken from the mixture and added to a test tube containing 4.5 mL of PBS buffer. After shaking, 0.5 mL of the bacterial solution was taken from the test tube and added to a test tube containing 4.5 mL of PBS buffer. This process was repeated 10 times. Then, 0.5 mL of the bacterial solution was taken from each test tube and added to a 15 mL agar culture dish. The bacterial solution was evenly distributed in the culture dish using a glass spreader. The culture dish was inverted and incubated in a constant temperature incubator at 37°C for 24 h. The culture dish was removed and the number of colonies was counted. The antibacterial rate of the cellulose membrane was calculated.

[0047] The antibacterial rate (%) = (A-B) / A, where A is the number of colonies in the blank group, and B is the number of colonies in the experimental group.

[0048]

[0049] As shown in the above table, with the increase of the content of the halamine carboxylic acid pyridine quaternary ammonium salt intermediate in the cellulose membrane, the content of the quaternary ammonium salt and the amount of active chlorine released after chlorination also increased, and the antibacterial rates against E. coli and S. aureus gradually increased, indicating that the cellulose membrane after graft modification had good antibacterial performance. In Example 4, the antibacterial rates against E. coli and S. aureus were 99.99% and 100%, respectively. This is because, on the one hand, the antibacterial cellulose membrane contains quaternary ammonium salt structures with positive ions, and the cellulose surface has negative ions. Through electrostatic adsorption, the bacteria are adsorbed into the internal voids, causing the bacterial biofilm to wrinkle, damaging the cell membrane and leading to the death of the bacteria. On the other hand, the Cl atom in the N-Cl bond has oxidizing properties after chlorination of the halamine by sodium hypochlorite. During the contact between the halamine and the bacteria, the oxidized chlorine is transferred to the acceptor site of the bacteria, oxidizing the thiol group or chlorinating the amino group in the protein, thereby inactivating the microorganisms. The grafted fiber with a dual antibacterial mechanism can quickly adsorb bacteria to the fiber surface through strong adsorption, and the halamine on the fiber surface can release high-concentration active chlorine to quickly kill the adsorbed live bacteria, thereby greatly improving the antibacterial performance. Grafting the halamine quaternary ammonium salt to the cellulose surface and fixing it greatly improves the antibacterial performance and stability, reduces the loss of the antibacterial agent, and reduces the pollution to the surrounding environment.

[0050] Comparative Example 1 does not contain a pyridine quaternary ammonium salt cationic structure, and the antibacterial rates against E. coli and S. aureus are 82.52% and 85.43% respectively, having a certain antibacterial effect, but not as good as the examples; Comparative Example 2 is an epoxy quaternary ammonium salt cellulose membrane, and the epoxy group can react with the hydroxyl group on the surface of cellulose to form a linkage, and the antibacterial rates against E. coli and S. aureus are 62.40% and 57.13% respectively, and the antibacterial performance is poor.

[0051] Water washing stability test: the prepared cellulose membrane was immersed in deionized water for 3h, taken out and dried, and the antibacterial rates against E. coli and S. aureus were tested by the shaking method after 20 and 50 times of repetition respectively.

[0052]

[0053] From the above test results, it can be seen that with the increase of the number of water washing, the antibacterial rates of the antibacterial cellulose membrane against E. coli and S. aureus are all decreased compared with the antibacterial rates without water washing, but the decrease is not large. After 20 times of water washing, the antibacterial rate of the antibacterial cellulose membrane against E. coli can still be maintained above 90%, and after 50 times of water washing, the antibacterial rate against S. aureus can be maintained at a high antibacterial rate level of above 90%, and the highest antibacterial rate can reach 99.99%, indicating that even after multiple water washing, the active chlorine of quaternary ammonium salt and halamine can still play its high efficient antibacterial effect, so that the prepared halamine quaternary ammonium salt antibacterial cellulose membrane has strong water washing stability and antibacterial regeneration, which is because the crosslinking agent hexamethylene diisocyanate links the hydroxyl group of the halamine carboxylic acid pyridine quaternary ammonium salt intermediate with the hydroxyl group of the cellulose fiber, so that the cellulose molecules are combined closely and are not easy to be damaged, and the carboxyl group in the molecular structure has hydrophilic effect and good compatibility with cellulose fiber, so that the small molecule antibacterial agent can be fixed on the fiber surface, greatly improving the antibacterial durability and stability.

[0054] Hydrophilic performance test: the water contact angle of the tested cellulose membrane was measured by a water contact angle instrument, and each membrane sample was tested 3 times to take the average value.

[0055]

[0056] The water contact angle can reflect the hydrophilic property of the membrane surface. From the above test results, it can be seen that the water contact angle of the pure cellulose membrane in Comparative Example 3 is 61.2°, and the water contact angle of Example 5 is 48.3°, indicating that the hydrophilic property of the cellulose membrane of Example 5 is better than that of Comparative Example 3, which is because the halamine quaternary ammonium salt antibacterial cellulose membrane in the example contains carboxyl groups with strong hydrophilic property, and has good compatibility with cellulose, which helps to improve the hydrophilic property of the cellulose membrane; the antibacterial cellulose membrane in Comparative Example 1 does not contain carboxylic acid groups, and its water contact angle is 66.1°, and the hydrophilic property is poor.

[0057] The above description is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacements or changes according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method for synthesizing a haloamine quaternary ammonium salt antibacterial cellulose membrane, characterized in that, The synthesis method is carried out according to the following steps: (1) Add cellulose fibers and N,N-dimethylacetamide to the reaction flask, stir evenly at a speed of 4000-6000 r / min, and add the following: The intermediate of haloamine carboxylic acid pyridine quaternary ammonium salt and hexamethylene diisocyanate were stirred and reacted. After the reaction was completed, the solution was cast into a film, degassed, dried, washed with water and ethanol, and dried to obtain a cellulose film containing haloamine pyridine quaternary ammonium salt. (2) Prepare an aqueous solution of sodium hypochlorite, adjust the pH to neutral with concentrated sulfuric acid, then put the cellulose membrane containing haloamine pyridine quaternary ammonium salt into the aqueous solution of sodium hypochlorite, immerse it at 20-35℃ for 2-5 hours, wash with deionized water, and dry to obtain the antibacterial cellulose membrane of haloamine quaternary ammonium salt.

2. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 1, characterized in that, In step (1), the mass of the haloamine carboxylic acid pyridine quaternary ammonium salt intermediate and the hexamethylene diisocyanate are 0.5-5% and 1.2-15% of the mass of cellulose fiber, respectively.

3. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 1, characterized in that, The reaction temperature in step (1) is 60-75℃ and the reaction time is 2-4h.

4. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 1, characterized in that, The sodium hypochlorite aqueous solution in step (2) has a mass fraction of 5-10%.

5. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 1, characterized in that, The synthesis method of the haloamine carboxylic acid pyridine quaternary ammonium salt intermediate in step (1) is carried out according to the following steps: S1. Add isonicotinic acid and acetonitrile to the reaction flask, stir well, add epichlorohydrin, stir to react, after the reaction is completed, concentrate under reduced pressure, recrystallize from ethanol to obtain the epoxy carboxylic acid pyridine quaternary ammonium salt intermediate. S2. Add the epoxy carboxylic acid pyridine quaternary ammonium salt intermediate, hydroxyethyl hydantoin and tetrahydrofuran to the reaction flask, stir well, add potassium hydroxide, react at 25-40℃ for 5-10 h, adjust the pH with concentrated hydrochloric acid, concentrate under reduced pressure, recrystallize with ethanol to obtain the haloamine carboxylic acid pyridine quaternary ammonium salt intermediate.

6. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 5, characterized in that, In step S1, the mass of epichlorohydrin is 160-210% of the mass of isonicotinic acid.

7. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 5, characterized in that, In step S1, the reaction temperature is 20-35℃ and the reaction time is 18-36h.

8. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 5, characterized in that, In step S2, the mass of hydroxyethyl hydantoin and potassium hydroxide are 105-130% and 70-120% of the mass of the epoxy carboxylic acid pyridine quaternary ammonium salt intermediate, respectively.

9. The method for synthesizing the haloamine quaternary ammonium salt antibacterial cellulose membrane according to claim 5, characterized in that, In step S2, the pH is adjusted to 3-5 using concentrated hydrochloric acid.

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