A high oil absorption antibacterial composite fiber membrane and its preparation method

Abstract

The present invention relates to the technical field of functional materials, specifically to a high-oil-absorption antibacterial composite fiber membrane and a preparation method thereof. The high-oil-absorption antibacterial composite fiber membrane in the present invention includes an oil-absorbing expansion membrane layer and an oil-philic barrier membrane layer. The raw material for preparing the oil-philic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer, which has excellent lipophilicity and hydrophobicity. When in contact with the oil-water mixture to be separated, it can allow the oily substance to quickly penetrate through, and at the same time can effectively intercept the water in the oil-water mixture from penetrating into the membrane; when preparing the oil-absorbing resin, a polymer prepared with butyl acrylate and lauryl methacrylate as the main monomer raw materials is obtained by electrostatic spinning, has a large oil absorption capacity, and expands in volume after oil absorption, and has good oil absorption sealing and oil retention; adding modified attapulgite can increase the oil absorption capacity, and adding modified acrylamide monomer can improve the mechanical properties and antibacterial properties of the oil-absorbing expansion membrane layer.

Description

Technical Field

[0001] The present invention relates to the technical field of functional materials, in particular to an antibacterial composite fiber membrane with high oil absorption and a preparation method thereof. Background Art

[0002] Oil-water mixtures are often generated in our daily lives and production. Whether for water purification or oil recovery, separation is essential. Fiber membranes, with their large surface area and high porosity, are an effective method for treating oil-water emulsions due to their high separation efficiency, ease of operation, and environmental friendliness.

[0003] Du Wenjun et al. published "Application of Chitosan-based Nanofiber Membranes in Air Filtration and Oil-Water Separation", which uses alkali-treated chitosan and polyvinyl alcohol as raw materials, and prepares chitosan / polyvinyl alcohol fiber membranes through electrospinning technology, which have good filtration performance, antibacterial performance and oil-water separation performance. The fiber membrane absorbs water in the oil-water mixture through the hydrophilic groups contained in both chitosan and polyvinyl alcohol molecules to achieve oil-water separation, but the fiber membrane is not suitable for oil-water separation in areas with high water content such as marine crude oil pollution, and the separation effect is not good. Chinese patent CN104313796B discloses a method for manufacturing a fiber membrane for oil-water separation, which uses suspension polymerization and electrospinning technology to prepare an extremely hydrophobic organic polymer fiber membrane with oil-water separation function, but the fiber membrane has insufficient antibacterial performance, and oil substances are prone to corruption and deterioration during the process of being adsorbed, transported with the fiber membrane, and then re-extracted. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the present invention provides a high oil absorption antibacterial composite fiber membrane and a preparation method thereof to solve the problems of poor separation effect and poor antibacterial performance of the oil-water separation fiber membrane in the existing technology.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing an antibacterial composite fiber membrane with high oil absorption capacity comprises the following steps:

[0007] Step 1: adding γ-methacryloxypropyltrimethoxysilane to an ethanol aqueous solution, stirring, adding attapulgite, reacting, purifying, and drying after the reaction to obtain modified attapulgite;

[0008] Adding acrylamide to a sulfuric acid aqueous solution, dissolving it, adding dicyandiamide, reacting it, adding alkali solution to adjust the pH value to 7.5-8.5, continuing the reaction, continuing stirring after the reaction, purifying it, and drying it to obtain modified acrylamide;

[0009] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0010] The dispersant is added to deionized water, heated and stirred to dissolve, and after complete dissolution, cooled, cetyltrimethylammonium bromide and azobisisobutylamidine hydrochloride are added, stirred and dissolved, and then the monomer mixture is added to obtain a pre-emulsion;

[0011] Hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride are added to deionized water and dissolved to obtain a mixed solution. The first part of the pre-emulsion is added to the mixed solution, and the mixture is reacted under nitrogen protection. After the reaction is completed, the second part of the pre-emulsion is added dropwise. After the addition is completed, the reaction is continued under nitrogen protection. After the reaction is completed, the mixture is purified and dried to obtain an oil-absorbing resin.

[0012] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide, heat and stir until uniformly dispersed, and electrospin to obtain an oil-absorbing expansion film layer;

[0013] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer with N-methylpyrrolidone, heating and stirring until uniformly dispersed, and electrospinning using the oil-absorbing expansion film layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0014] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, and the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer.

[0015] Furthermore, when the high oil absorption antibacterial composite fiber membrane is used for oil-water separation, the lipophilic barrier membrane layer of the high oil absorption antibacterial composite fiber membrane is brought into contact with the liquid surface of the oil-water mixture to be separated.

[0016] Preferably, in the step one, when preparing the modified attapulgite, the stirring conditions are: stirring at a stirring speed of 300-500 r / min for 30-50 min; the mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and ethanol aqueous solution is 15: (15.5-16.5): (95-105), and the reaction conditions are: stirring at a speed of 300-500 r / min and reacting at a temperature of 45-55 ° C for 4-5 h.

[0017] Preferably, the ethanol aqueous solution is a 95wt% ethanol aqueous solution;

[0018] The attapulgite is dried at a temperature of 100-110° C. for 3.5-4.5 hours.

[0019] Preferably, the purification comprises filtration and washing.

[0020] Preferably, in the step 1, when preparing the modified acrylamide, the mass ratio of acrylamide, sulfuric acid aqueous solution, and dicyandiamide is 3.5:(50-55):4.2, and the reaction conditions are: heating under reflux and stirring at a temperature of 120-130°C for 1.5-2.5h, and the conditions for continuing the reaction are: heating under reflux and stirring at a temperature of 120-130°C for 0.5-1.5h.

[0021] Preferably, the condition for continuing stirring is: stirring at room temperature until a white solid precipitates and the amount of the precipitated white solid no longer increases.

[0022] Preferably, the sulfuric acid aqueous solution is a 10 wt% sulfuric acid aqueous solution; and the alkali solution is a sodium hydroxide aqueous solution.

[0023] Furthermore, the concentration of the sodium hydroxide aqueous solution is 5 mol / L.

[0024] Preferably, the purification includes filtration and washing.

[0025] Preferably, in the step 2, when preparing the pre-emulsion, the mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, dispersant, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is (128-135):(254-260):(20-30):(80-90):(2-4):(3-5):(400-500):(2.5-3):(1.5-2).

[0026] Preferably, in step 2, when preparing the mixed solution, the mass of deionized water is 40%-50% of the mass of the deionized water used to prepare the pre-emulsion, the mass of cetyltrimethylammonium bromide is 5%-15% of the mass of cetyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutyramidine hydrochloride is 50%-70% of the mass of azobisisobutyramidine hydrochloride used to prepare the pre-emulsion.

[0027] Preferably, in step 2, the first part of the pre-emulsion accounts for 5%-10% of the total mass of the pre-emulsion, and the reaction conditions are: stirring the reaction at 75-80°C for 1-2 hours, and the conditions for continuing the reaction are: reacting at 80-90°C for 2-3 hours.

[0028] Preferably, the second portion of the pre-emulsion is added dropwise for 1.5-2.5 hours.

[0029] Preferably, the dispersant comprises polyvinyl alcohol.

[0030] Preferably, the purification comprises filtration and washing.

[0031] Preferably, in the step 3, the mass ratio of the oil absorbing resin to N,N-dimethylformamide is (15-25):(75-85), and the temperature of heating and stirring is 85-95°C;

[0032] The electrospinning parameters were as follows: electrospinning voltage 24 kV, needle flow rate of the syringe pump 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25° C., and relative humidity 50%.

[0033] Preferably, in the step 4, the mass ratio of polyvinylidene fluoride-hexafluoropropylene copolymer to N-methylpyrrolidone is (10-20):(80-90), and the heating and stirring temperature is 85-95° C.;

[0034] The electrospinning parameters were as follows: electrospinning voltage 24 kV, needle flow rate of the syringe pump 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25° C., and relative humidity 50%.

[0035] Preferably, in order to improve the bonding strength between the oleophilic barrier film layer and the oil-absorbing swelling film layer, the oleophilic barrier film layer and the oil-absorbing swelling film layer in the high oil-absorbing antibacterial composite fiber membrane are sewn together by yarn.

[0036] Preferably, the yarn comprises polyester (PET) yarn with a yarn count of 40-60S, preferably 45S.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The high oil absorption antibacterial composite fiber membrane of the present invention includes an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material for preparing the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer, which has excellent oleophilicity and hydrophobicity. When in contact with the oil-water mixture to be separated, it can allow the oily substance to penetrate quickly and effectively block the water of the oil-water mixture from penetrating into the membrane. When preparing the oil-absorbing resin, a polymer prepared with butyl acrylate and lauryl methacrylate as the main monomer raw materials is prepared by electrospinning. Butyl acrylate and lauryl methacrylate are both oleophilic non-polar monomers. Butyl acrylate, as a short-chain branched monomer, has a good interactive structure. Lauryl methacrylate, as a long-chain branched monomer, not only has good oil absorption performance, but also has a large steric hindrance effect at one end of the long branched chain during the polymerization process. In the polymer molecule, the molecular chain and the branched chain are affected by the environmental steric hindrance and bond angle, causing curling and entanglement. The arrangement of the polymer molecules also produces steric hindrance due to the branched chain structure, preventing the molecular chains from being tightly entangled. There are many pores in the internal structure of the resin, which enables the oil-absorbing and expanding film layer to absorb a large amount of oily substance molecules that penetrate from the oleophilic barrier film layer. After oil absorption, the molecular chain undergoes solvation, stretching the molecular chain and gradually expanding in volume, resulting in a high oil absorption rate and good oil absorption, sealing and oil retention.

[0039] In the present invention, when preparing the oil-absorbing resin, acrylamide monomer is added to improve the mechanical properties of the oil-absorbing and expanding film layer, such as toughness and tensile strength. In addition, acrylamide is modified and reacts with dicyandiamide to produce biguanide groups, which have excellent antibacterial properties.

[0040] In the present invention, attapulgite is added when preparing the oil-absorbing resin. The attapulgite has abundant micropores and a large specific surface area, which can increase the oil absorption capacity of the oil-absorbing swelling film layer. Moreover, the attapulgite is modified, which not only enhances the lipophilicity of the attapulgite, but also allows the olefinic groups introduced through the modification to participate in the polymerization reaction, thereby improving the dispersion uniformity and compatibility of the attapulgite in the resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a process flow chart for preparing the antibacterial composite fiber membrane with high oil absorption capacity of the present invention;

[0042] Figure 2 A bar chart showing the oil absorption performance test results of the composite fiber membranes prepared in Examples 1-6 of the present invention and Comparative Examples 1-2;

[0043] Figure 3 This is a bar chart showing the antibacterial performance test results of the composite fiber membranes prepared in Examples 1-6 of the present invention and Comparative Examples 1-2;

[0044] Figure 4A bar chart showing the tensile strength test results of the composite fiber membranes prepared in Examples 1-6 of the present invention and Comparative Examples 1-2;

[0045] Figure 5 This is a bar chart showing the elongation at break test results of the composite fiber membranes prepared in Examples 1-6 of the present invention and Comparative Examples 1-2. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0047] Example 1

[0048] A method for preparing an antibacterial composite fiber membrane with high oil absorption capacity comprises the following steps:

[0049] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 300r / min for 50min, adding attapulgite, and reacting at a stirring speed of 300r / min at a temperature of 45°C for 5h. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12h to obtain modified attapulgite;

[0050] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:15.5:95; the attapulgite is dried at a temperature of 100° C. for 4.5 hours.

[0051] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, and then dicyandiamide was added. The mixture was heated, stirred, and refluxed at 120° C. for 2.5 hours at a stirring speed of 150 r / min. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH value to 7.5. The mixture was heated, refluxed, and stirred at 120° C. for 1.5 hours. After the reaction, the mixture was stirred at room temperature at a stirring speed of 150 r / min until a white solid precipitated and the amount of the precipitated white solid no longer increased. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 hours to obtain modified acrylamide.

[0052] The mass ratio of acrylamide, sulfuric acid aqueous solution and dicyandiamide is 3.5:50:4.2;

[0053] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0054] Add polyvinyl alcohol 1788 (average degree of polymerization 1700, degree of alcoholysis 88%) to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0055] The mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 128:254:20:80:2:3:400:2.5:1.5;

[0056] cetyltrimethylammonium bromide and azobisisobutylammonium hydrochloride are added to deionized water, the mass of the deionized water is 40% of the mass of the deionized water used to prepare the pre-emulsion, the mass of the cetyltrimethylammonium bromide is 5% of the mass of the cetyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of the azobisisobutylammonium hydrochloride is 50% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolution, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, the first part of the pre-emulsion accounts for 5% of the total mass of the pre-emulsion. Under nitrogen protection, the mixture is stirred at 75°C and a stirring speed of 150r / min for 2h. After the reaction is completed, the second part of the pre-emulsion is added dropwise for 1.5h. After the addition is completed, the mixture is stirred at 80°C and a stirring speed of 150r / min for 3h. After the reaction is completed, the mixture is filtered, washed with deionized water, and dried in a vacuum drying oven at 60°C for 10h to obtain an oil-absorbing resin;

[0057] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 15:85, heat and stir at 85°C until the dispersion is uniform, and electrospin to obtain an oil-absorbing expansion film layer;

[0058] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0059] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 10:90, heating and stirring at 85° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0060] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0061] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0062] In the high oil absorption antibacterial composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0063] Example 2

[0064] A method for preparing an antibacterial composite fiber membrane with high oil absorption capacity comprises the following steps:

[0065] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 500r / min for 30min, adding attapulgite, stirring at a stirring speed of 500r / min and a temperature of 55°C for 4h, after the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12h to obtain modified attapulgite;

[0066] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:16.5:105; the attapulgite is dried at a temperature of 110° C. for 3.5 h.

[0067] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, followed by addition of dicyandiamide, and the mixture was heated under reflux with stirring at a speed of 250 r / min and a temperature of 130° C. for 1.5 h. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 8.5, and the mixture was heated under reflux with stirring at a speed of 250 r / min and a temperature of 130° C. for 0.5 h. After the reaction, the mixture was stirred at room temperature at a speed of 250 r / min until a white solid precipitated and the amount of the precipitated white solid did not increase. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 h to obtain modified acrylamide.

[0068] The mass ratio of acrylamide, sulfuric acid aqueous solution and dicyandiamide is 3.5:55:4.2;

[0069] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0070] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0071] The mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 135:260:30:90:4:5:500:3:2;

[0072] Add hexadecyltrimethylammonium bromide and azobisisobutylammonium hydrochloride into deionized water, wherein the mass of the deionized water is 50% of the mass of the deionized water used to prepare the pre-emulsion, the mass of hexadecyltrimethylammonium bromide is 15% of the mass of the hexadecyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutylammonium hydrochloride is 70% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolving, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution. The first part of the pre-emulsion is added to the mixed solution. The mixture accounts for 10% of the total mass of the pre-emulsion, and is stirred at 80°C and a stirring speed of 150 r / min under nitrogen protection for 1 hour. After the reaction is completed, the second part of the pre-emulsion is added dropwise for 2.5 hours. After the addition is completed, the mixture is stirred at 90°C and a stirring speed of 150 r / min for 2 hours under nitrogen protection. After the reaction is completed, it is filtered, washed with deionized water, and placed in a vacuum drying oven at 60°C for 10 hours to obtain an oil-absorbing resin;

[0073] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 25:75, heat and stir at 95° C. until uniformly dispersed, and electrospin to obtain an oil-absorbing expansion film layer;

[0074] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0075] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 20:80, heating and stirring at 95° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0076] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0077] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0078] In the high oil absorption antibacterial composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0079] Example 3

[0080] A method for preparing an antibacterial composite fiber membrane with high oil absorption capacity comprises the following steps:

[0081] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 400 r / min for 40 minutes, adding attapulgite, and reacting at a stirring speed of 400 r / min and a temperature of 50°C for 4.5 hours. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12 hours to obtain modified attapulgite;

[0082] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:16:100; the attapulgite is dried at a temperature of 105° C. for 4 hours;

[0083] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, followed by addition of dicyandiamide, and the mixture was heated under stirring at 200 r / min and 125° C. for 2 h. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 8.5, and the mixture was heated under reflux and stirred at 200 r / min and 125° C. for 1 h. After the reaction, the mixture was stirred at room temperature at 200 r / min until a white solid precipitated and the amount of the precipitated white solid no longer increased. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 h to obtain modified acrylamide.

[0084] Among them, the mass ratio of acrylamide, sulfuric acid aqueous solution, and dicyandiamide is 3.5:51:4.2;

[0085] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0086] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0087] The mass ratios of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride are 129:256:22:82:2.4:3.4:420:2.6:1.6;

[0088] Add hexadecyltrimethylammonium bromide and azobisisobutylammonium hydrochloride into deionized water, wherein the mass of the deionized water is 45% of the mass of the deionized water used to prepare the pre-emulsion, the mass of hexadecyltrimethylammonium bromide is 10% of the mass of the hexadecyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutylammonium hydrochloride is 60% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolving, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, wherein the first part of the pre-emulsion accounts for 60% of the mass of the azobisisobutylammonium hydrochloride. 6% of the total mass of the pre-emulsion, under nitrogen protection, at a temperature of 77 ° C, a stirring speed of 150 r / min, stirring for 1.5 hours, after the reaction is completed, the second part of the pre-emulsion is added dropwise for 2 hours, after the addition is completed, under nitrogen protection, at a temperature of 85 ° C, a stirring speed of 150 r / min, stirring for 2.5 hours, after the reaction is completed, filter, wash with deionized water, and place in a vacuum drying oven at 60 ° C for 10 hours to obtain an oil-absorbing resin;

[0089] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 20:80, heat and stir at 90° C. until uniformly dispersed, and electrospin to obtain an oil-absorbing expansion film layer;

[0090] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0091] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 15:85, heating and stirring at 90° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0092] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0093] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0094] In the high oil absorption antibacterial composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0095] Example 4

[0096] A method for preparing an antibacterial composite fiber membrane with high oil absorption capacity comprises the following steps:

[0097] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 400 r / min for 40 minutes, adding attapulgite, and reacting at a stirring speed of 400 r / min and a temperature of 50°C for 4.5 hours. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12 hours to obtain modified attapulgite;

[0098] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:16:100; the attapulgite is dried at a temperature of 105° C. for 4 hours;

[0099] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, followed by addition of dicyandiamide, and the mixture was heated under stirring at 200 r / min and 125° C. for 2 h. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 8.5, and the mixture was heated under reflux and stirred at 200 r / min and 125° C. for 1 h. After the reaction, the mixture was stirred at room temperature at 200 r / min until a white solid precipitated and the amount of the precipitated white solid no longer increased. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 h to obtain modified acrylamide.

[0100] The mass ratio of acrylamide, sulfuric acid aqueous solution and dicyandiamide is 3.5:52:4.2;

[0101] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0102] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0103] The mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 131:257:24:84:2.8:3.8:440:2.7:1.7;

[0104] Add hexadecyltrimethylammonium bromide and azobisisobutylammonium hydrochloride into deionized water, wherein the mass of the deionized water is 45% of the mass of the deionized water used to prepare the pre-emulsion, the mass of hexadecyltrimethylammonium bromide is 10% of the mass of the hexadecyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutylammonium hydrochloride is 60% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolving, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, wherein the first part of the pre-emulsion accounts for 60% of the mass of the azobisisobutylammonium hydrochloride. 6% of the total mass of the pre-emulsion, under nitrogen protection, at a temperature of 78 ° C, a stirring speed of 150 r / min, stirring for 1.5 hours, after the reaction is completed, the second part of the pre-emulsion is added dropwise for 2 hours, after the addition is completed, under nitrogen protection, at a temperature of 85 ° C, a stirring speed of 150 r / min, stirring for 2.5 hours, after the reaction is completed, filter, wash with deionized water, and place in a vacuum drying oven at 60 ° C for 10 hours to obtain an oil-absorbing resin;

[0105] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 20:80, heat and stir at 90° C. until uniformly dispersed, and electrospin to obtain an oil-absorbing expansion film layer;

[0106] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0107] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 15:85, heating and stirring at 90° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0108] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0109] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0110] In the high oil absorption antibacterial composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0111] Example 5

[0112] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 400 r / min for 40 minutes, adding attapulgite, and reacting at a stirring speed of 400 r / min and a temperature of 50°C for 4.5 hours. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12 hours to obtain modified attapulgite;

[0113] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:16:100; the attapulgite is dried at a temperature of 105° C. for 4 hours;

[0114] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, followed by addition of dicyandiamide, and the mixture was heated under stirring at 200 r / min and 125° C. for 2 h. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 8.5, and the mixture was heated under reflux and stirred at 200 r / min and 125° C. for 1 h. After the reaction, the mixture was stirred at room temperature at 200 r / min until a white solid precipitated and the amount of the precipitated white solid no longer increased. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 h to obtain modified acrylamide.

[0115] The mass ratio of acrylamide, sulfuric acid aqueous solution and dicyandiamide is 3.5:53:4.2;

[0116] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0117] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0118] The mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 133:258:26:86:3.2:4.2:460:2.8:1.8;

[0119] Add hexadecyltrimethylammonium bromide and azobisisobutylammonium hydrochloride into deionized water, wherein the mass of the deionized water is 45% of the mass of the deionized water used to prepare the pre-emulsion, the mass of hexadecyltrimethylammonium bromide is 10% of the mass of the hexadecyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutylammonium hydrochloride is 60% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolving, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, wherein the first part of the pre-emulsion accounts for 60% of the mass of the azobisisobutylammonium hydrochloride. 6% of the total mass of the pre-emulsion, under nitrogen protection, at a temperature of 78 ° C, a stirring speed of 150 r / min, stirring for 1.5 hours, after the reaction is completed, the second part of the pre-emulsion is added dropwise for 2 hours, after the addition is completed, under nitrogen protection, at a temperature of 85 ° C, a stirring speed of 150 r / min, stirring for 2.5 hours, after the reaction is completed, filter, wash with deionized water, and place in a vacuum drying oven at 60 ° C for 10 hours to obtain an oil-absorbing resin;

[0120] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 20:80, heat and stir at 90° C. until uniformly dispersed, and electrospin to obtain an oil-absorbing expansion film layer;

[0121] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0122] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 15:85, heating and stirring at 90° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0123] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0124] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0125] The thickness of the oleophilic barrier membrane layer of the high oil absorption antibacterial composite fiber membrane is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0126] Example 6

[0127] A method for preparing an antibacterial composite fiber membrane with high oil absorption capacity comprises the following steps:

[0128] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 400 r / min for 40 minutes, adding attapulgite, and reacting at a stirring speed of 400 r / min and a temperature of 50°C for 4.5 hours. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12 hours to obtain modified attapulgite;

[0129] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:16:100; the attapulgite is dried at a temperature of 105° C. for 4 hours;

[0130] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, followed by addition of dicyandiamide, and the mixture was heated under stirring at 200 r / min and 125° C. for 2 h. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH to 8.5, and the mixture was heated under reflux and stirred at 200 r / min and 125° C. for 1 h. After the reaction, the mixture was stirred at room temperature at 200 r / min until a white solid precipitated and the amount of the precipitated white solid no longer increased. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 h to obtain modified acrylamide.

[0131] The mass ratio of acrylamide, sulfuric acid aqueous solution and dicyandiamide is 3.5:54:4.2;

[0132] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0133] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0134] The mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 134:259:28:88:3.6:4.6:480:2.9:1.9;

[0135] Add hexadecyltrimethylammonium bromide and azobisisobutylammonium hydrochloride into deionized water, wherein the mass of the deionized water is 45% of the mass of the deionized water used to prepare the pre-emulsion, the mass of hexadecyltrimethylammonium bromide is 10% of the mass of the hexadecyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutylammonium hydrochloride is 60% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolving, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, wherein the first part of the pre-emulsion accounts for 60% of the mass of the azobisisobutylammonium hydrochloride. 6% of the total mass of the pre-emulsion, under nitrogen protection, at a temperature of 78 ° C, a stirring speed of 150 r / min, stirring for 1.5 hours, after the reaction is completed, the second part of the pre-emulsion is added dropwise for 2 hours, after the addition is completed, under nitrogen protection, at a temperature of 85 ° C, a stirring speed of 150 r / min, stirring for 2.5 hours, after the reaction is completed, filter, wash with deionized water, and place in a vacuum drying oven at 60 ° C for 10 hours to obtain an oil-absorbing resin;

[0136] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 20:80, heat and stir at 90° C. until uniformly dispersed, and electrospin to obtain an oil-absorbing expansion film layer;

[0137] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0138] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 15:85, heating and stirring at 90° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain an antibacterial composite fiber membrane with high oil absorption;

[0139] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0140] The high oil absorption antibacterial composite fiber membrane comprises an oil absorption expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0141] In the high oil absorption antibacterial composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0142] Comparative Example 1

[0143] A method for preparing a composite fiber membrane comprises the following steps:

[0144] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 300r / min for 50min, adding attapulgite, and reacting at a stirring speed of 300r / min at a temperature of 45°C for 5h. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12h to obtain modified attapulgite;

[0145] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:15.5:95; the attapulgite is dried at a temperature of 100° C. for 4.5 hours.

[0146] Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0147] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0148] The mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 128:254:20:36.5:2:3:400:2.5:1.5;

[0149] cetyltrimethylammonium bromide and azobisisobutylammonium hydrochloride are added to deionized water, the mass of the deionized water is 40% of the mass of the deionized water used to prepare the pre-emulsion, the mass of the cetyltrimethylammonium bromide is 5% of the mass of the cetyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of the azobisisobutylammonium hydrochloride is 50% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolution, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, the first part of the pre-emulsion accounts for 5% of the total mass of the pre-emulsion. Under nitrogen protection, the mixture is stirred at 75°C and a stirring speed of 150r / min for 2h. After the reaction is completed, the second part of the pre-emulsion is added dropwise for 1.5h. After the addition is completed, the mixture is stirred at 80°C and a stirring speed of 150r / min for 3h. After the reaction is completed, the mixture is filtered, washed with deionized water, and dried in a vacuum drying oven at 60°C for 10h to obtain an oil-absorbing resin;

[0150] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 15:85, heat and stir at 85°C until the dispersion is uniform, and electrospin to obtain an oil-absorbing expansion film layer;

[0151] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0152] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 10:90, heating and stirring at 85° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain a composite fiber membrane;

[0153] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0154] The composite fiber membrane comprises an oil-absorbing expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0155] In the composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0156] Comparative Example 2

[0157] A method for preparing a composite fiber membrane comprises the following steps:

[0158] Step 1, adding γ-methacryloxypropyltrimethoxysilane to a 95wt% ethanol aqueous solution, stirring at a stirring speed of 300r / min for 50min, adding attapulgite, and reacting at a stirring speed of 300r / min at a temperature of 45°C for 5h. After the reaction is completed, filtering, washing with ethanol, and placing in a vacuum drying oven at 60°C for 12h to obtain modified attapulgite;

[0159] The mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and 95 wt% ethanol aqueous solution is 15:15.5:95; the attapulgite is dried at a temperature of 100° C. for 4.5 hours.

[0160] Acrylamide was added to a 10 wt % aqueous sulfuric acid solution and dissolved, and then dicyandiamide was added. The mixture was heated, stirred, and refluxed at 120° C. for 2.5 hours at a stirring speed of 150 r / min. After the reaction, a 5 mol / L aqueous sodium hydroxide solution was added to adjust the pH value to 7.5. The mixture was heated, refluxed, and stirred at 120° C. for 1.5 hours. After the reaction, the mixture was stirred at room temperature at a stirring speed of 150 r / min until a white solid precipitated and the amount of the precipitated white solid no longer increased. The mixture was filtered, washed with deionized water, and dried in a vacuum drying oven at 60° C. for 12 hours to obtain modified acrylamide.

[0161] The mass ratio of acrylamide, sulfuric acid aqueous solution and dicyandiamide is 3.5:50:4.2;

[0162] Step 2: mixing butyl acrylate, methyl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture;

[0163] Add polyvinyl alcohol 1788 to deionized water, heat and stir to dissolve, cool after complete dissolution, add hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride, stir to dissolve, and then add the monomer mixture to obtain a pre-emulsion;

[0164] The mass ratio of butyl acrylate, methyl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, polyvinyl alcohol 1788, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is 128:100:20:80:2:3:400:2.5:1.5;

[0165] cetyltrimethylammonium bromide and azobisisobutylammonium hydrochloride are added to deionized water, the mass of the deionized water is 40% of the mass of the deionized water used to prepare the pre-emulsion, the mass of the cetyltrimethylammonium bromide is 5% of the mass of the cetyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of the azobisisobutylammonium hydrochloride is 50% of the mass of the azobisisobutylammonium hydrochloride used to prepare the pre-emulsion. After dissolution, a mixed solution is obtained, and the first part of the pre-emulsion is added to the mixed solution, the first part of the pre-emulsion accounts for 5% of the total mass of the pre-emulsion. Under nitrogen protection, the mixture is stirred at 75°C and a stirring speed of 150r / min for 2h. After the reaction is completed, the second part of the pre-emulsion is added dropwise for 1.5h. After the addition is completed, the mixture is stirred at 80°C and a stirring speed of 150r / min for 3h. After the reaction is completed, the mixture is filtered, washed with deionized water, and dried in a vacuum drying oven at 60°C for 10h to obtain an oil-absorbing resin;

[0166] Step 3: Disperse the oil-absorbing resin in N,N-dimethylformamide at a mass ratio of 15:85, heat and stir at 85°C until the dispersion is uniform, and electrospin to obtain an oil-absorbing expansion film layer;

[0167] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0168] Step 4: Mixing polyvinylidene fluoride-hexafluoropropylene copolymer and N-methylpyrrolidone at a mass ratio of 10:90, heating and stirring at 85° C. until uniform dispersion, and electrospinning using the oil-absorbing expansion membrane layer as a receiving substrate to obtain a composite fiber membrane;

[0169] The electrospinning parameters were as follows: electrospinning voltage 24 kV, syringe pump needle flow rate 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

[0170] The composite fiber membrane comprises an oil-absorbing expansion membrane layer and an oleophilic barrier membrane layer, wherein the raw material of the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer;

[0171] In the composite fiber membrane: the thickness of the oleophilic barrier membrane layer is 0.05 mm, the average fiber diameter is 300 nm, the thickness of the oil absorption expansion membrane layer is 0.1 mm, and the average fiber diameter is 1.2 μm.

[0172] In the above embodiments and comparative examples, polyvinylidene fluoride-hexafluoropropylene copolymer was purchased from Dongguan Taotao Plastic Materials Co., Ltd., brand: Arkema, model: 2801; attapulgite was obtained by ball-milling commercially available 3000-mesh attapulgite to an average particle size of 12500 mesh.

[0173] Test example

[0174] The performance tests of the composite fiber membranes prepared in Examples 1-6 and Comparative Examples 1-2 were performed:

[0175] (1) Oil absorption performance test: Kerosene was used as the test object, and a 25 mm*25 mm sample of the composite fiber membrane was made. The sample was weighed and recorded, and placed in a mixture of kerosene and water. The oleophilic barrier membrane layer was in contact with the liquid surface of the mixture of kerosene and water. After absorbing oil for 5 hours, the sample was weighed and recorded, and the oil absorption rate of the composite fiber membrane for kerosene was calculated. The composite fiber membrane after oil absorption was centrifuged at a speed of 2000 r / min for 5 minutes, and the sample was weighed and recorded. The oil retention rate of the composite fiber membrane for kerosene was calculated. The results of the oil absorption rate and oil retention rate are shown in Table 1:

[0176] Table 1

[0177] Oil absorption rate (g / g) Oil retention rate (%) Oil absorption rate (g / g) Oil retention rate (%) Example 1 13.0 94.9 Example 5 13.2 94.9 Example 2 13.1 95.1 Example 6 13.1 95.0 Example 3 1.33 95.2 Comparative Example 1 12.9 94.9 Example 4 13.1 94.8 Comparative Example 2 6.5 88.3

[0178] As can be seen from Table 1, the composite fiber membrane prepared by the present invention has excellent oil absorption performance. The composite fiber membrane includes an oil-absorbing expansion membrane layer and an oleophilic barrier membrane layer. The raw material for preparing the oleophilic barrier membrane layer is polyvinylidene fluoride-hexafluoropropylene copolymer, which has excellent oleophilicity and hydrophobicity. When in contact with the oil-water mixture to be separated, it can allow the oily substance to quickly penetrate through, and at the same time can effectively intercept the water of the oil-water mixture from penetrating into the membrane; the raw material for preparing the oil-absorbing expansion membrane layer contains both non-polar short-chain branched monomers and long-chain branched monomers, which not only has good oil absorption performance, but also the curled and entangled molecular chains undergo solvation after oil absorption, the molecular chains stretch, and the volume gradually expands, which can increase the oil absorption rate and oil retention rate. Compared with Example 1, in Comparative Example 1, the acrylamide was not modified, and there was no significant effect on the oil absorption performance of the composite fiber membrane; in Comparative Example 2, no long-chain branched monomer was used, so oil absorption and expansion did not occur, the oil absorption performance decreased, and the oil absorption rate and oil retention rate decreased.

[0179] (2) Antibacterial performance test: The antibacterial effect of the composite fiber membrane on Staphylococcus aureus, Candida albicans and Escherichia coli was tested. The test results are shown in Table 2:

[0180] Table 2

[0181]

[0182]

[0183] Table 2 shows that the composite fiber membrane produced by the present invention exhibits excellent antimicrobial properties. During the preparation of the oil-absorbing resin, the acrylamide monomer undergoes a modification process, whereby the acrylamide reacts with dicyandiamide to produce biguanide groups, which exhibit excellent antimicrobial properties. Compared to Example 1, in Comparative Example 1, where the acrylamide was not modified to introduce biguanide groups, the antimicrobial properties of the composite fiber membrane were significantly reduced. In Comparative Example 2, where no long-chain branched monomers were used, the antimicrobial properties of the composite fiber membrane were not significantly affected.

[0184] (3) Mechanical properties test: The tensile strength and elongation at break of the oil-absorbing and swelling membrane layer of the composite fiber membrane were tested. The test results are shown in Table 3:

[0185] Table 3

[0186]

[0187] As can be seen from Table 3, the composite fiber membrane prepared in the present invention has good mechanical properties. When preparing the oil-absorbing resin, adding acrylamide can improve the toughness and tensile strength of the oil-absorbing and swelling membrane layer.

[0188] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an antibacterial composite fiber membrane with high oil absorption, characterized in that: The following steps are involved: Step 1: adding γ-methacryloxypropyltrimethoxysilane to an ethanol aqueous solution, stirring, adding attapulgite, reacting, purifying, and drying after the reaction to obtain modified attapulgite; Adding acrylamide to a sulfuric acid aqueous solution, dissolving it, adding dicyandiamide, reacting it, adding alkali solution to adjust the pH value to 7.5-8.5, continuing the reaction, continuing stirring after the reaction, purifying it, and drying it to obtain modified acrylamide; The reaction conditions are: heating under reflux and stirring at 120-130°C for 1.5-2.5h, and the conditions for continued reaction are: heating under reflux and stirring at 120-130°C for 0.5-1.5h; Step 2: mixing butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, and divinylbenzene, and stirring to obtain a monomer mixture; The dispersant is added to deionized water, heated and stirred to dissolve, and after complete dissolution, cooled, cetyltrimethylammonium bromide and azobisisobutylamidine hydrochloride are added, stirred and dissolved, and then the monomer mixture is added to obtain a pre-emulsion; Wherein, the dispersant comprises polyvinyl alcohol; Hexadecyltrimethylammonium bromide and azobisisobutylamidine hydrochloride are added to deionized water and dissolved to obtain a mixed solution. The first part of the pre-emulsion is added to the mixed solution, and the mixture is reacted under nitrogen protection. After the reaction is completed, the second part of the pre-emulsion is added dropwise. After the addition is completed, the reaction is continued under nitrogen protection. After the reaction is completed, the mixture is purified and dried to obtain an oil-absorbing resin. The reaction conditions are: stirring at 75-80°C for 1-2 hours, and the conditions for continued reaction are: stirring at 80-90°C for 2-3 hours; Step 3: Dispersing the oil-absorbing resin into N,N-dimethylformamide, heating and stirring, and electrospinning to obtain an oil-absorbing expansion film layer; Step 4: Mix polyvinylidene fluoride-hexafluoropropylene copolymer with N-methylpyrrolidone, heat and stir, and use the oil-absorbing and expanding membrane layer as a receiving substrate for electrostatic spinning to obtain an antibacterial composite fiber membrane with high oil absorption.

2. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step one, when preparing the modified attapulgite, the stirring conditions are: stirring at a stirring speed of 300-500 r / min for 30-50 min; the mass ratio of attapulgite, γ-methacryloxypropyltrimethoxysilane, and ethanol aqueous solution is 15:(15.5-16.5):(95-105), and the reaction conditions are: reacting at a stirring speed of 300-500 r / min and a temperature of 45-55°C for 4-5 h.

3. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step 1, when preparing the modified acrylamide, the mass ratio of acrylamide, sulfuric acid aqueous solution, and dicyandiamide is 3.5:(50-55):4.

2.

4. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step 2, when preparing the pre-emulsion, the mass ratio of butyl acrylate, lauryl methacrylate, modified attapulgite, modified acrylamide, divinylbenzene, dispersant, deionized water, hexadecyltrimethylammonium bromide, and azobisisobutylamidine hydrochloride is (128-135):(254-260):(20-30):(80-90):(1-2):(3-5):(400-500):(2.5-3):(1.5-2).

5. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step 2, when preparing the mixed solution, the mass of deionized water is 40%-50% of the mass of the deionized water used to prepare the pre-emulsion, the mass of cetyltrimethylammonium bromide is 15%-15% of the mass of cetyltrimethylammonium bromide used to prepare the pre-emulsion, and the mass of azobisisobutyramidine hydrochloride is 50%-70% of the mass of azobisisobutyramidine hydrochloride used to prepare the pre-emulsion.

6. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step 2, the first part of the pre-emulsion accounts for 5%-10% of the total mass of the pre-emulsion.

7. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step 3, the mass ratio of the oil absorbing resin to N,N-dimethylformamide is (15-25): (75-85), and the heating and stirring temperature is 85-95°C; The electrospinning parameters were as follows: electrospinning voltage 24 kV, needle flow rate of the syringe pump 0.8 mL / h, needle diameter 1.2 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

8. The method for preparing an antibacterial composite fiber membrane with high oil absorption according to claim 1, characterized in that: In the step 4, the mass ratio of polyvinylidene fluoride-hexafluoropropylene copolymer to N-methylpyrrolidone is (10-20): (80-90), and the heating and stirring temperature is 85-95° C.; The electrospinning parameters were as follows: electrospinning voltage 24 kV, needle flow rate of the syringe pump 0.4 mL / h, needle diameter 0.6 mm, spinning distance 20 cm, spinning temperature 25 °C, and relative humidity 50%.

9. An antibacterial composite fiber membrane with high oil absorption prepared by the method for preparing an antibacterial composite fiber membrane with high oil absorption according to any one of claims 1 to 8.

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