阅读说明：本技术 一种复合纳米纤维膜及其制备方法和应用 (Composite nanofiber membrane and preparation method and application thereof ) 是由 王琛 颜琨 冯伟忠 高云莉 孙元娜 于 2020-05-27 设计创作，主要内容包括：本发明公开了复合纳米纤维膜的制备方法,包括以下步骤：1)制备氧化石墨烯分散液；2)将纳米二氧化硅粉末和聚丙烯腈加入到氧化石墨烯分散液中,随后加入金属离子,得到静电纺丝溶液；3)将静电纺丝溶液通过静电纺丝,得到复合纳米纤维膜。通过氧化石墨烯纳米颗粒的加入提高粗糙度及吸附性能,进一步提高复合纳米纤维膜的过滤效果,在不影响过滤效率的情况下,过滤阻力降到40.67Pa,降幅较大；通过添加金属离子,使复合纳米纤维膜在过滤的同时具有优良的抗菌性。本发明制备得到的复合纳米纤维膜可以制备成高效低阻抑菌的空气过滤材料,适用于室内空气过滤和PM2.5个体防护,具有很好的实用价值。(The invention discloses a preparation method of a composite nanofiber membrane, which comprises the following steps: 1) preparing a graphene oxide dispersion liquid; 2) adding nano silicon dioxide powder and polyacrylonitrile into graphene oxide dispersion liquid, and then adding metal ions to obtain an electrostatic spinning solution; 3) and (3) carrying out electrostatic spinning on the electrostatic spinning solution to obtain the composite nanofiber membrane. The roughness and the adsorption performance are improved by adding the graphene oxide nanoparticles, the filtering effect of the composite nanofiber membrane is further improved, the filtering resistance is reduced to 40.67Pa under the condition that the filtering efficiency is not influenced, and the reduction amplitude is large; by adding metal ions, the composite nanofiber membrane has excellent antibacterial property while filtering. The composite nanofiber membrane prepared by the method can be prepared into an efficient and low-resistance antibacterial air filtering material, is suitable for indoor air filtration and PM2.5 individual protection, and has good practical value.)

1. A preparation method of a composite nanofiber membrane is characterized by comprising the following steps:

1) preparing a graphene oxide dispersion liquid;

2) preparing an electrostatic spinning solution:

adding nano silicon dioxide powder and polyacrylonitrile into the graphene oxide dispersion liquid obtained in the step 1), heating and stirring, then adding metal ions, and uniformly mixing to obtain an electrostatic spinning solution;

wherein, calculated by mass percent, polyacrylonitrile: metal ions: electrostatic spinning solution (10-15): (0.5-4.5): 100, respectively;

and (3) graphene oxide: nano silicon dioxide powder: polyacrylonitrile (0.3-2): (2-6): 100, respectively;

3) and (3) performing electrostatic spinning on the electrostatic spinning solution obtained in the step 2) to obtain the composite nanofiber membrane.

2. The method for preparing a composite nanofiber membrane as claimed in claim 1, wherein the step 1) is specifically: and placing the graphene oxide in a solvent, and performing ultrasonic treatment to obtain a graphene oxide dispersion liquid.

3. The method for preparing a composite nanofiber membrane as claimed in claim 2, wherein the solvent is N, N dimethylacetamide or dimethylsulfoxide.

4. The preparation method of the composite nanofiber membrane as claimed in claim 2, wherein in the step 1), the ultrasonic treatment time is 30-120 min.

5. The method of claim 1, wherein the metal ions are selected from the group consisting of Ag, Cu, Fe and W.

6. The method for preparing a composite nanofiber membrane as claimed in claim 1, wherein the electrospinning conditions are: the distance between the needle and the receiver is 15 cm-25 cm, and the spinning voltage is 12 KV-18 KV.

7. The composite nanofiber membrane prepared by the method for preparing a composite nanofiber membrane as claimed in any one of claims 1 to 6.

8. The composite nanofiber membrane according to claim 7, wherein the composite nanofiber membrane has an average diameter of 340 to 410 nm.

9. The composite nanofiber membrane as claimed in claim 7, wherein the filtration resistance of the composite nanofiber membrane is 36-48.5 Pa.

10. Use of the composite nanofiber membrane of claim 7 in the preparation of an air filter material.

Technical Field

The invention belongs to the technical field of nanofiber membranes, and particularly relates to a composite nanofiber membrane and a preparation method and application thereof.

Background

In recent years, with the rapid development of industrial production and automobile industry, environmental pollution is increased, and especially inhalable particulate matters such as PM2.5 (commonly called haze and also called fine particulate matters) become one of the most concerned indexes at the present stage. PM2.5 can be suspended in the air for a long time, the higher the content concentration of the PM in the air, the more serious the air pollution is, the health of people is seriously threatened, and the requirements on the improvement of the living quality and the environmental purification are very urgent. Therefore, the development of a high-performance filter material is one of effective measures.

The air filter material mainly comprises a fiber filter material, a membrane filter material, a porous carbon material (such as activated carbon and the like), a porous ceramic material (such as zeolite and the like), a porous metal material and the like. The fiber air filtering material is developed rapidly by the advantages of simple process, low cost, easy structure control, excellent filtering effect and the like. The nanofiber air filter material rapidly draws attention of people due to the characteristics of small fiber diameter, large specific surface area, high porosity and the like. Recently, electrospun nanofibers have been favored by filter material researchers because of their advantages such as extremely large specific surface area, porosity, and extremely high filtration accuracy. The nano-scale fiber with the diameter of dozens or hundreds of nanometers can be obtained by utilizing the electrostatic spinning method, and is very suitable for being used as a filter material. The application of the electrostatic spinning nanofiber product to the air filtering technology provides a new way for manufacturing high-precision air filtering materials.

The filtering material prepared by the electrostatic spinning method at present has large filtering resistance and can not meet the market demand.

Disclosure of Invention

One of the purposes of the invention is to provide a preparation method of a composite nanofiber membrane, which increases graphene oxide for modification and reduces filtration resistance.

The second object of the present invention is to provide a composite nanofiber membrane having a lower filtration resistance and antibacterial properties.

The invention also aims to provide application of the composite nanofiber membrane.

The invention is realized by the following technical scheme:

a preparation method of a composite nanofiber membrane comprises the following steps:

1) preparing a graphene oxide dispersion liquid;

2) preparing an electrostatic spinning solution:

adding nano silicon dioxide powder and polyacrylonitrile into the graphene oxide dispersion liquid obtained in the step 1), heating and stirring, then adding metal ions, and uniformly mixing to obtain an electrostatic spinning solution;

wherein, calculated by mass percent, polyacrylonitrile: metal ions: electrostatic spinning solution (10-15): (0.5-4.5): 100, respectively;

and (3) graphene oxide: nano silicon dioxide powder: polyacrylonitrile (0.3-2): (2-6): 100, respectively;

3) and (3) performing electrostatic spinning on the electrostatic spinning solution obtained in the step 2) to obtain the composite nanofiber membrane.

Further, the step 1) is specifically as follows: placing graphene oxide in a solvent, and performing ultrasonic treatment to obtain a graphene oxide dispersion liquid;

further, in the step 1), the solvent is N, N-dimethylacetamide or dimethyl sulfoxide.

Further, in the step 1), the ultrasonic treatment time is 30-120 min.

Further, the metal ion is specifically any one or two of Ag, Cu, Fe and W elements.

Further, the electrospinning conditions were: the distance between the needle and the receiver is 15 cm-25 cm, and the spinning voltage is 12 KV-18 KV.

The invention also discloses a composite nanofiber membrane prepared by the preparation method of the composite nanofiber membrane.

Furthermore, the average diameter of the composite nanofiber membrane is 340-410 nm.

Furthermore, the filtration resistance of the composite nanofiber membrane is 36-48.5 Pa.

The invention also discloses application of the composite nanofiber membrane in preparation of an air filter material.

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

according to the preparation method of the composite nanofiber membrane, the graphene oxide and the silicon dioxide are loaded on the polyacrylonitrile by means of an electrostatic spinning technology, and the roughness and the adsorption performance of the fiber membrane are improved by adding the graphene oxide nanoparticles and the silicon dioxide; and after GO is added, the fiber diameter tends to decrease. In the diameter distribution table, the fiber diameter mode decreases from 490nm to 340 nm. Obviously, during the spinning process of GO, the lamellar orientation effect of GO can effectively promote the reduction of the fiber diameter so as to reduce the pore diameter of the nanofiber membrane and further improve the adsorption performance. In conclusion, the roughness and the adsorption performance of the fiber membrane are further improved by adding the graphene oxide nanoparticles, the filtering effect of the composite nanofiber membrane is further improved, the filtering resistance can be reduced to 40.67Pa under the condition of not influencing the filtering efficiency, and the reduction amplitude is large; the physical size of the electrospun fiber has high controllability, high specific surface area and developed porosity, which is beneficial to filtering particulate matters; by adding the metal ions, the composite nanofiber membrane has excellent antibacterial property while having filtering performance due to the antibacterial property of the metal ions.

Furthermore, graphene oxide sheet layers with different sizes are obtained under the ultrasonic stripping condition, so that the graphene oxide is better loaded on polyacrylonitrile.

The composite nanofiber membrane disclosed by the invention has lower filtration resistance, antibacterial property and excellent performance.

The composite nanofiber membrane disclosed by the invention can be prepared into an efficient and low-resistance antibacterial air filtering material, is suitable for indoor air filtration and PM2.5 individual protection, and has a very good practical value.

Drawings

FIG. 1 is a topographical view of graphene oxide lamellae obtained after ultrasonic exfoliation in accordance with the present invention;

FIG. 2 is a scanning electron microscope image of the composite nanofiber prepared by the present invention;

FIG. 3 is a graph showing the effect of the addition of graphene oxide on the filtration efficiency and filtration resistance of 500 nm NaCl particles according to the present invention;

FIG. 4 shows the effect of the addition amount of graphene oxide on the quality factor.

Detailed Description

The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.