阅读说明：本技术 一种抗菌性阴离子交换膜的制备方法 (Preparation method of antibacterial anion exchange membrane ) 是由 姚宇洋 沈江南 阮慧敏 廖俊斌 陈权 于 2021-06-01 设计创作，主要内容包括：本发明公开了一种抗菌性阴离子交换膜的制备方法,按照以下步骤进行：步骤1：取BPPO溶解于NMP得到均相溶液；步骤2：将硫酸庆大霉素进行纯化得纯净庆大霉素；向步骤1所得的均相溶液中加入纯净庆大霉素进行共混,得到均相铸膜液；步骤3：将步骤2的均相铸膜液进行抽滤,在室温条件下加入三甲胺,充分季铵化反应后,放入真空干燥箱进行脱泡；步骤4：步骤3所得的均相铸膜液倾倒在玻璃模具上,得到流延膜,然后立即放入真空干燥箱常温真空脱气,再真空干燥,再使膜在去离子水中与玻璃模具自然脱离；步骤5：将步骤4得到的膜洗涤得到抗菌性阴离子交换膜。本发明所制得的阴离子交换膜具有较高的离子容量、抗菌性并且有良好的持久性。(The invention discloses a preparation method of an antibacterial anion exchange membrane, which comprises the following steps: step 1: dissolving BPPO in NMP to obtain a homogeneous solution; step 2: purifying gentamicin sulfate to obtain pure gentamicin; adding pure gentamicin into the homogeneous phase solution obtained in the step 1 for blending to obtain a homogeneous phase membrane casting solution; and step 3: carrying out suction filtration on the homogeneous casting solution obtained in the step (2), adding trimethylamine at room temperature, carrying out full quaternization reaction, and then placing the mixture into a vacuum drying oven for defoaming; and 4, step 4: pouring the homogeneous casting solution obtained in the step 3 onto a glass mold to obtain a casting film, immediately placing the casting film into a vacuum drying oven for vacuum degassing at normal temperature, then performing vacuum drying, and naturally separating the film from the glass mold in deionized water; and 5: and (4) washing the membrane obtained in the step (4) to obtain the antibacterial anion exchange membrane. The anion exchange membrane prepared by the invention has higher ion capacity, antibacterial property and favorable durability.)

1. A preparation method of an antibacterial anion exchange membrane comprises the following steps:

step 1: dissolving BPPO in NMP, stirring for 0.5-3 hours at 40-100 ℃ in a nitrogen atmosphere, and filtering to obtain a homogeneous solution; wherein the charge ratio of BPPO and NMP is (0.45-1.50) g: 15 mL;

step 2: calcium hydroxide and gentamicin sulfate were mixed at room temperature in a 1: (5-8) dissolving in deionized water by mass ratio, stirring for 24-48 hours, filtering insoluble substances, freezing at-30-50 ℃ for 48-72 hours, and freeze-drying to obtain pure gentamicin; adding pure gentamicin into the homogeneous phase solution obtained in the step 1 at room temperature, heating to 40-100 ℃, blending for 6-12h, and cooling to room temperature to obtain a homogeneous phase membrane casting solution; wherein the feeding mass ratio of the pure gentamicin to the BPPO in the homogeneous phase solution is 1: (3-9);

and step 3: and (3) carrying out suction filtration on the homogeneous phase casting solution obtained in the step (2), and carrying out vacuum filtration on the homogeneous phase casting solution at room temperature according to the ratio of trimethylamine to BPPO of 1: (7-10) adding trimethylamine according to the mass ratio, fully performing quaternization reaction, and then placing the mixture into a vacuum drying oven for defoaming for 1-3 hours;

and 4, step 4: pouring the homogeneous casting solution obtained in the step 3 onto a glass mold to obtain a casting film, immediately placing the casting film into a vacuum drying oven, vacuum degassing at normal temperature for 1-3 hours, vacuum drying at 55-65 ℃ for 24-36 hours, and naturally separating the film from the glass mold in deionized water;

and 5: and (4) washing the membrane obtained in the step (4) to obtain the antibacterial anion exchange membrane.

2. The method of claim 1, wherein: the BPPO material is subjected to impurity removal treatment before being used in the step 1, and the impurity removal treatment comprises the following steps: soaking BPPO in deionized water for 0.5-2 hours, cleaning with ethanol for 3-5 times, vacuum drying, dissolving in NMP at 40-100 deg.C under nitrogen atmosphere, filtering with sand core funnel, and vacuum drying to obtain purified BPPO.

3. The method of claim 1, wherein: in the step 1, the mass fraction of BPPO in the prepared homogeneous solution is 2.83-8.86%.

4. The method of claim 1, wherein: in step 1, the mass fraction of BPPO in the prepared homogeneous solution is 4-7%.

5. The method of claim 1, wherein: in step 1, stirring is carried out at 50-90 ℃ for 1.5-2.5 hours under nitrogen atmosphere.

6. The method of claim 1, wherein: in the step 2, the gentamicin sulfate and the calcium hydroxide are dissolved in the deionized water and stirred for 36 to 48 hours at the temperature of 25 ℃, then filtered by a sand core funnel, the clear liquid is taken out, frozen for 60 to 72 hours at the temperature of minus 45 to 40 ℃, and freeze-dried to the anhydrous condition to obtain the pure flocculent gentamicin.

7. The method of claim 1, wherein: in step 2, a proper amount of gentamicin is added into the homogeneous solution in step 1 at room temperature, and the temperature is raised to 50-90 ℃ for blending for 8-10 hours.

8. The method of claim 1, wherein: in the step 3, the quaternization reaction conditions are as follows: reacting at room temperature for 8-12 h.

9. The method of claim 1, wherein: in step 4, vacuum drying is carried out for 30-36 hours at the temperature of 60-65 ℃.

10. The method of claim 1, wherein: in step 5, the washing reagent is deionized water.

The technical field is as follows:

the invention relates to the technical field of membrane material preparation and separation, in particular to a preparation method of an antibacterial anion exchange membrane.

Technical background:

water is taken as a life source, the shortage of fresh water resources in the world is a problem which is increasingly concerned by people, while seawater accounts for 96.5 percent of the total water storage in the world, and the importance of the daily production and life of human beings can not leave water resources. Nowadays, with the increasing exhaustion of global resources, the problem of water shortage becomes more serious, and the pollution of water resources is also intensified, and a new method for purifying sewage and desalinating seawater is sought as a primary objective.

Ion exchange membranes, one of the most advanced separation membranes in the twenty-first century, have been widely used in various fields such as electrodialysis, diffusion dialysis, electrolysis, various batteries, sensor materials, medical applications, and chemical analyses. Electrodialysis technology is receiving attention because of its high water recovery, long equipment life and low operating cost, and has irreplaceable great advantages for separation of non-isotropic ions, even isotropic ions. Electrodialysis is a technology that utilizes the permselectivity of ion exchange membranes to ions to make the ions directionally migrate under the push of an external direct current electric field force, thereby achieving the separation, purification and concentration of electrolyte solution.

However, conventional ion exchange membranes are highly susceptible to bio-contamination during use and placement due to the inherent physicochemical surface properties of the polymer. Bacteria adhere to the membrane surface by secreting extracellular polymers, resulting in an increase in membrane resistance, which in turn affects the ion transfer efficiency, energy consumption and service life of the ion exchange membrane. In practical application, an ion exchange membrane with antibacterial property is sought.

A common treatment is to periodically rinse the ion exchange membrane contaminated with bacteria with chemical reagents. But various costs are increased and certain harm is caused to the environment, and in order to radically solve the biological pollution problem of the ion exchange membrane, the membrane material needs to be subjected to antibacterial modification so as to be endowed with antibacterial performance. The antibacterial agent, such as nano silver, nano copper, nano titanium and the like, is embedded into the polymer matrix, so that the doped ion exchange membrane has certain antibacterial performance. However, such a method has a certain limitation, and the nanoparticles are periodically precipitated and converted into metal ions, which causes loss of the reagent, and thus the durability of the antibacterial performance cannot be ensured.

The invention content is as follows:

the invention aims to provide a method for preparing an antibacterial anion exchange membrane by a chemical assembly method, the method is simple and effective and is more beneficial to commercialization, and the prepared anion exchange membrane has higher ionic capacity, antibacterial property and good durability.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a preparation method of an antibacterial anion exchange membrane comprises the following steps:

step 1: dissolving BPPO in NMP, stirring for 0.5-3 hours at 40-100 ℃ in a nitrogen atmosphere, and filtering to obtain a homogeneous solution; wherein the charge ratio of BPPO and NMP is (0.45-1.50) g: 15 mL;

step 2: calcium hydroxide and gentamicin sulfate were mixed at room temperature in a 1: (5-8) dissolving in deionized water by mass ratio, stirring for 24-48 hours, filtering insoluble substances, freezing at-30-50 ℃ for 48-72 hours, and freeze-drying to obtain pure gentamicin; adding pure gentamicin into the homogeneous phase solution obtained in the step 1 at room temperature, heating to 40-100 ℃, blending for 6-12h, and cooling to room temperature to obtain a homogeneous phase membrane casting solution; wherein the feeding mass ratio of the pure gentamicin to the BPPO in the homogeneous phase solution is 1: (3-9);

and step 3: and (3) carrying out suction filtration on the homogeneous phase casting solution obtained in the step (2), and carrying out vacuum filtration on the homogeneous phase casting solution at room temperature according to the ratio of trimethylamine to BPPO of 1: (7-10) adding trimethylamine according to the mass ratio, fully performing quaternization reaction, and then placing the mixture into a vacuum drying oven for defoaming for 1-3 hours;

and 4, step 4: pouring the homogeneous casting solution obtained in the step 3 onto a glass mold to obtain a casting film, immediately placing the casting film into a vacuum drying oven, vacuum degassing at normal temperature for 1-3 hours, vacuum drying at 55-65 ℃ for 24-36 hours, and naturally separating the film from the glass mold in deionized water;

and 5: and (4) washing the membrane obtained in the step (4) to obtain the antibacterial anion exchange membrane.

In the invention, BPPO and gentamicin solid are co-dissolved in NMP, then are blended at 40-100 ℃, the antibacterial performance is realized by a blending method, and a part of bromine is left in the BPPO to have quaternization reaction with trimethylamine, so that an ion channel is realized.

In the invention, the BPPO material is preferably subjected to impurity removal treatment before being used in the step 1, and the impurity removal treatment is carried out according to the following operation: soaking BPPO in deionized water for 0.5-2 hours, cleaning with ethanol for 3-5 times, vacuum drying, dissolving in NMP at 40-100 deg.C under nitrogen atmosphere, filtering with sand core funnel, and vacuum drying to obtain high-purity BPPO raw material.

In step 1 of the present invention, the mass fraction of BPPO in the prepared homogeneous solution is preferably 2.83% to 8.86%, and more preferably 4% to 7%.

In step 1 of the present invention, it is preferable to stir at 50 to 90 ℃ for 1.5 to 2.5 hours under a nitrogen atmosphere.

In the step 2 of the invention, preferably, the gentamicin sulfate and the calcium hydroxide are dissolved in the deionized water and stirred for 36-48 hours at 25 ℃, then filtered by a sand core funnel, the clear liquid is taken out, frozen for 60-72 hours at minus 45-40 ℃, and freeze-dried to anhydrous condition to obtain the pure flocculent gentamicin.

In step 2 of the invention, preferably, a proper amount of gentamicin is added into the homogeneous solution in step 1 at room temperature, the temperature is raised to 50-90 ℃, and blending reaction is carried out for 8-10 hours at the optimal condition of 80 ℃.

In step 3 of the invention, the quaternization reaction conditions are as follows: reacting for 8-12h at room temperature, and optimally reacting for 12 h.

In step 4 of the present invention, it is preferable to dry the mixture at 60 to 65 ℃ for 30 to 36 hours under vacuum, and the most preferable condition is vacuum drying at 60 ℃ for 36 hours.

In step 5 of the present invention, the washing reagent is deionized water.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a simple and effective method for preparing an anion exchange membrane with antibacterial performance by blending, wherein a high-temperature resistant antibiotic gentamicin is selected, can stably exist in the reaction, is different from the variability of other antibiotics at high temperature, and is firstly blended at high temperature and then quaternary ammonium reaction is carried out by using excessive halogen groups of BPPO to generate an ion channel, so that the anion exchange membrane with antibacterial performance is prepared. The antibacterial anion exchange membrane prepared by the invention has higher ion exchange capacity, antibacterial property and good durability.

Drawings

FIG. 1 is a pictorial representation of a membrane prepared in example 2 without trimethylammonium functionalization;

FIG. 2 is a pictorial representation of a trimethylammonium functionalized membrane prepared in example 4;

FIG. 3 is a bacteriostatic ring diagram of four gentamicin blend films prepared in examples 1-4 against Staphylococcus aureus, where 1: BPPO-0.14-T; 2: BPPO-0.14; 3: BPPO; 4: BPPO-0.4-T;

FIG. 4 is a plot of the inhibition rings of the four gentamicin blend membranes prepared in examples 1-4 against Bacillus, where 1: BPPO-0.4-T; 2: BPPO; 3: BPPO-0.14; 4: BPPO-0.14-T;

FIG. 5 shows the bacteriostatic effect of BPPO, BPPO-0.14, BPPO-0.40 membranes on Staphylococcus aureus after soaking in deionized water for 7 days, wherein 1: BPPO; 2: BPPO-0.4; BPPO-0.14;

FIG. 6 is an IR spectrum of four gentamicin blend membranes prepared in examples 1-4, from top to bottom, BPPO-0.4-T, BPPO-0.14-T, BPPO-0.14, BPPO, respectively;

FIG. 7 is an IEC plot of four gentamicin blend membranes (BPPO-0.14-T BPPO-0.22-T; BPPO-0.32-T; BPPO-0.40-T) of examples 1-4.

Detailed Description

The technical solution of the present invention is further illustrated by the following specific examples, but the scope of the present invention is not limited thereto:

gentamicin sulfate, NMP, calcium hydroxide and trimethylamine used in the embodiment of the invention are purchased from Allantin technologies, Inc.; BPPO was purchased from Shandong Tianwei Membrane technology Co., Ltd, and the strain of the present invention was provided by cell culture and metabolic engineering team laboratories of bioengineering institute of Industrial university, Zhejiang.

Example 1

And (2) soaking BPPO in deionized water for 2 hours, cleaning, then cleaning with ethanol for 5 times, vacuum drying, dissolving in NMP at 40 ℃ in a nitrogen atmosphere, filtering with a sand core funnel, and vacuum drying to obtain the BPPO raw material with high purity. BPPO1.200g which has been purified is accurately weighed and dissolved in a three-necked flask containing 15mL of NMP, and the solution is stirred at 40 ℃ for 3 hours under a nitrogen atmosphere. And after complete dissolution, filtering the solution through a sand core funnel to obtain pure BPPO casting solution, cooling the obtained solution to room temperature, pouring the obtained homogeneous casting solution on a glass grinding tool by using a casting method, defoaming the homogeneous casting solution for 3 hours in vacuum, and drying the homogeneous casting solution in vacuum at the temperature of 60 ℃ for 36 hours. And taking out, cooling to room temperature, and naturally separating the film from the glass plate under the deionized water condition. Then washing with deionized water for 3 times, and soaking for 24 hours to obtain the un-blended BPPO membrane.

Example 2

And (2) soaking BPPO in deionized water for 2 hours, cleaning, then cleaning with ethanol for 5 times, vacuum drying, dissolving in NMP at 40 ℃ in a nitrogen atmosphere, filtering with a sand core funnel, and vacuum drying to obtain the BPPO raw material with high purity. 1.200g of BPPO which had been purified was accurately weighed out and dissolved in a three-necked flask containing 15mL of NMP, and the solution was stirred at 40 ℃ for 3 hours under a nitrogen atmosphere. And after the BPPO membrane is completely dissolved, filtering the solution by a sand core funnel to obtain pure BPPO membrane casting solution. 0.296g of calcium hydroxide and 2.302g of gentamicin sulfate are dissolved in deionized water and stirred for 48 hours, insoluble substances are filtered, and the mixture is frozen for 72 hours at minus 40 ℃, and then pure gentamicin is obtained by freeze drying. And cooling the obtained pure BPPO casting solution to room temperature, adding 0.140g of purified gentamicin, blending for 12 hours at 80 ℃, cooling to room temperature, filtering by using a sand core funnel, pouring the obtained homogeneous casting solution on a glass grinding tool by using a tape casting method, defoaming for 3 hours in vacuum, and drying for 36 hours in vacuum at 60 ℃. And taking out, cooling to room temperature, and naturally separating the film from the glass plate under the deionized water condition. Then washing with deionized water for 3 times, and soaking for 24h to obtain the BPPO-0.14 membrane.

Example 3

And (2) soaking BPPO in deionized water for 2 hours, cleaning, then cleaning with ethanol for 5 times, vacuum drying, dissolving in NMP at 40 ℃ in a nitrogen atmosphere, filtering with a sand core funnel, and vacuum drying to obtain the BPPO raw material with high purity. 1.200g of BPPO which had been purified was accurately weighed out and dissolved in a three-necked flask containing 15mL of NMP, and the solution was stirred at 40 ℃ for 3 hours under a nitrogen atmosphere. And after the BPPO membrane is completely dissolved, filtering the solution by a sand core funnel to obtain pure BPPO membrane casting solution. 0.296g of calcium hydroxide and 2.302g of gentamicin sulfate are dissolved in deionized water and stirred for 48 hours, insoluble substances are filtered, and the mixture is frozen for 72 hours at minus 40 ℃, and then pure gentamicin is obtained by freeze drying. Cooling the obtained pure BPPO casting solution to room temperature, adding 0.400g of purified gentamicin, blending for 12 hours at 80 ℃, cooling to room temperature, filtering by using a sand core funnel again, adding 0.168g of trimethylamine, reacting for 12 hours at room temperature, placing the mixture into a vacuum drying oven for defoaming for 3 hours, pouring the obtained homogeneous casting solution onto a glass grinding tool by using a tape casting method, immediately placing the homogeneous casting solution into the vacuum drying oven for vacuum degassing for 0.5 hour at normal temperature, and then performing vacuum drying for 36 hours at 60 ℃. And taking out, cooling to room temperature, and naturally separating the film from the glass plate under the deionized water condition. Then washing with deionized water for 3 times, and soaking for 24 hours to obtain the BPPO-0.4-T membrane blended with gentamicin.

Example 4

And (2) soaking BPPO in deionized water for 2 hours, cleaning, then cleaning with ethanol for 5 times, vacuum drying, dissolving in NMP at 40 ℃ in a nitrogen atmosphere, filtering with a sand core funnel, and vacuum drying to obtain the BPPO raw material with high purity. The purified BPPO1.200g was weighed out accurately and dissolved in a three-necked flask containing 15mL of NMP, and the solution was stirred at 40 ℃ for 3 hours under a nitrogen atmosphere. And after the BPPO membrane is completely dissolved, filtering the solution by a sand core funnel to obtain pure BPPO membrane casting solution. 0.296g of calcium hydroxide and 2.302g of gentamicin sulfate are dissolved in deionized water and stirred for 48 hours, insoluble substances are filtered, and the mixture is frozen for 72 hours at minus 40 ℃, and then pure gentamicin is obtained by freeze drying. Cooling the obtained solution to room temperature, adding 0.140g of purified gentamicin, blending for 12 hours at 80 ℃, cooling to room temperature, filtering by using a sand core funnel again, adding 0.168g of trimethylamine, reacting for 12 hours at room temperature, placing into a vacuum drying oven for defoaming for 3 hours, pouring the obtained homogeneous casting solution on a glass grinding tool by using a tape casting method, immediately placing into the vacuum drying oven for vacuum degassing for 0.5 hour at normal temperature, and then vacuum drying for 36 hours at 60 ℃. And taking out, cooling to room temperature, and naturally separating the film from the glass plate under the deionized water condition. Then washing with deionized water for 3 times, and soaking for 24h to obtain the BPPO-0.14-T membrane.

Example 5

With reference to example 4, except that the feed mass of purified gentamicin was 0.220g, BPPO-0.22-T membranes were prepared as in example 4.

Example 6

With reference to example 4, except that the feed mass of purified gentamicin was 0.320g, BPPO-0.32-T membranes were prepared as in example 4.

Example 7

With reference to example 4, except that the feed mass of purified gentamicin was 0.400g, BPPO-0.40-T membranes were prepared as in example 4.

Example 8

The antibacterial performance of the film samples prepared in examples 1-4 was judged by the bacteriostatic circle method, and the bacterial test used staphylococcus aureus test species. Taking 50 mu l of staphylococcus aureus bacterial liquid (provided by laboratories of cell culture and metabolic engineering teams of bioengineering college of Zhejiang industrial university), coating on an LB agar plate, disinfecting a membrane sample by using 75% ethanol, disinfecting the surface of the membrane sample for 30min by using ultraviolet light, uniformly coating the treated membrane sample on the LB agar plate coated with the bacterial liquid, and culturing at the constant temperature of 37 ℃ for 12-16 h. After the culture is finished, the size of the inhibition zone around the membrane is observed as shown in figure 3: the unmodified BPPO has almost no antibacterial effect, the blended BPPO-0.14 has the effect of inhibiting the growth of staphylococcus aureus on an LB agar plate (the radius of an antibacterial ring is 0.8cm), and the blended functionalized BPPO-0.14-T and the blended BPPO-0.4-T have better effects of inhibiting the growth of staphylococcus aureus on the LB agar plate (the radius of the antibacterial ring is 1.4cm and 1.7cm respectively).

Example 9

The antibacterial performance of the film samples prepared in examples 1 to 4 was judged by the bacteriostatic circle method, and the bacterial test employed bacillus test species. And (2) coating 50 mu l of bacillus liquid (provided by laboratories of cell culture and metabolic engineering teams of bioengineering college of Zhejiang industrial university) on an LB agar plate, disinfecting the membrane sample by using 75% ethanol, disinfecting the surface of the membrane sample for 30min by using ultraviolet light, uniformly pasting the treated membrane sample on the LB agar plate coated with the bacillus liquid, and culturing at the constant temperature of 37 ℃ for 12-16 h. After the culture is finished, the size of the inhibition zone around the membrane is observed as shown in figure 4: the unmodified BPPO has almost no antibacterial effect, the blended BPPO-0.14 has the effect of inhibiting the growth of the bacillus (the radius of a bacteriostatic zone is 0.7cm) on an LB agar plate, and the blended functionalized BPPO-0.14-T and the blended BPPO-0.4-T have better effects of inhibiting the growth of the bacillus (the radius of the bacteriostatic zone is 1.0cm and 1.1cm) on the LB agar plate.