Method for preparing nanofiber membrane using waste eggshell inner membrane as raw material

Abstract

The present application is about a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, and relates to the field of fiber membranes. The method comprises: pre-treating waste eggshell membranes to obtain eggshell membrane powder; dissolving the eggshell membrane powder in an aqueous solution and stirring until fully dissolved to obtain an eggshell membrane aqueous solution; adding a PEO polymer to the eggshell membrane aqueous solution and stirring fully to obtain a spinning solution; electrospinning the spinning solution in an electrostatic spinning machine to obtain a nanofiber membrane using waste eggshell inner membrane as raw material. The preparation method provided in the present application enhances the viscosity of the spinning solution and improves the toughness of the fiber membrane by blending PEO polymer with eggshell membrane. The obtained fiber membrane is not easy to be brittle, and the fiber diameter and distribution are uniform. It has good biocompatibility and degradability, and contains many bioactive substances, which play an important role in moisturizing, anti-wrinkle, and improving metabolism of the skin. The larger fiber specific surface area also enhances the adsorption capacity of the nanofiber membrane.

Description

Technical Field

[0001] The present application relates to the field of fiber membrane technology, and in particular to a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material. Background Art

[0002] my country is the country with the largest number of poultry farmers in the world, and its egg production ranks first in the world. With the increasing production and consumption of poultry eggs, the number of discarded eggshells is also increasing, which not only causes serious pollution to the environment, but also is an extreme waste of resources. These discarded eggshells contain hard egg shells and eggshell inner membranes with many effective ingredients, which are valuable raw materials for feed, medicine, food and other industries. Although some relatively mature research on eggshells has been carried out at home and abroad, such as the application of eggshell powder in food and medical fields, there is little research on the recovery and utilization of protein in the eggshell inner membrane.

[0003] The inner membrane of the eggshell (commonly known as "phoenix coat") is a fibrous biological film with a double-layer membrane structure located between the eggshell and the egg white. It has good air permeability, adsorption, moisture retention, stability and other characteristics. The eggshell membrane contains about 90% protein, 2% carbohydrates and 3% liposomes, of which the proteins are collagen, keratin, ovalbumin, lysozyme, etc. At present, eggshell membranes are widely used in the fields of medicine, light industry and daily cosmetics, such as promoting wound recovery and promoting smooth and delicate skin. At present, medical and health care textiles are generally in close contact with human skin, the fabric surface is relatively rough, and the skin affinity is poor, which is not conducive to the healing of wounds.

[0004] The eggshell membrane itself presents a relatively tight three-dimensional network structure, with good biocompatibility, biodegradability and the characteristics of promoting skin metabolism. The large fiber specific surface area gives it good adsorption. However, directly using the eggshell membrane on the human body surface will reduce its fit with the skin and reduce comfort. The eggshell membrane is brittle after drying, and its strength and durability are poor. In addition, the protein contained in the eggshell membrane will only show good functional properties in a dissolved state. The requirements for biomass activity, biocompatibility and biodegradability in the textile medical field are increasing, so there is a certain research value in the application of eggshell membrane in the textile field.

[0005] Electrospinning is a simple and efficient process for preparing polymer micro-nano fibers. It has the common advantages of low equipment and experimental costs, high fiber yield, and wide applicability. The prepared fibers have a three-dimensional spatial structure, large specific surface area, small pore size, high porosity and good continuity, and have attracted much attention in recent years.

[0006] Patent CN110592686B discloses a micro-nano composite membrane loaded with growth factors, which is composed of an eggshell membrane loaded with growth factors, a protein membrane, a hydrophilic micro-nano fiber layer and a hydrophobic micro-nano fiber layer. The eggshell membrane is used as a direct carrier of the growth factor, and the protein is deposited as a coating layer on the surface of the eggshell membrane loaded with growth factors by salting out to form a protein membrane, and then the hydrophilic micro-nano fiber membrane and the hydrophobic micro-nano fiber membrane are sequentially wrapped on the surface of the protein membrane by electrospinning technology; the protein membrane is obtained by salting out and depositing poultry egg white.

[0007] However, the above-mentioned prior art directly uses eggshell membrane as a carrier. The disadvantage of eggshell membrane being brittle after drying is not conducive to its reuse. In addition, the fiber membrane on the surface of eggshell membrane has uneven diameter and disorderly distribution, and small particles cannot be uniformly loaded, which affects the formation state of the composite membrane. Summary of the invention

[0008] The purpose of the present application is to provide a method for preparing nanofiber membranes using waste eggshell inner membranes as raw materials, so as to solve the problems of brittle fiber membranes and uneven fiber diameter and distribution in the above-mentioned prior art.

[0009] To achieve the above purpose, the technical solution adopted in this application is:

[0010] A method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, comprising:

[0011] S1, pretreating waste eggshell membranes to obtain eggshell membrane powder;

[0012] S2, dissolving the eggshell membrane powder obtained in step S1 in an aqueous solution and stirring until the eggshell membrane powder is fully dissolved to obtain an eggshell membrane aqueous solution;

[0013] S3, adding PEO polymer to the eggshell membrane aqueous solution obtained in step S2 and stirring them sufficiently to obtain a spinning solution;

[0014] S4. Electrospinning the spinning solution obtained in step S3 in an electrospinning machine to obtain a nanofiber membrane using the waste eggshell inner membrane as a raw material.

[0015] In a possible implementation, in step S1, pre-treating the waste eggshell membranes to obtain eggshell membrane powder comprises:

[0016] S11. Break fresh eggs and clean the white through blunt end;

[0017] S12, washing the eggshells thoroughly several times with ultrapure deionized water, and peeling off the eggshell membrane from the eggshells;

[0018] S13, washing the eggshell membrane with ethanol and deionized water to remove trace albumin;

[0019] S14, drying the eggshell membrane in a drying oven at 60° C. for 30 minutes and then grinding the eggshell membrane into powder to obtain eggshell membrane powder.

[0020] In a possible implementation, the ethanol concentration in step S13 is 40-60%.

[0021] In a possible implementation, the molecular weight of the PEO polymer in step S3 is 400,000-900,000.

[0022] In a possible implementation, the mass ratio of PEO to eggshell membrane powder in the spinning solution obtained in step S3 is 1:3-3:1.

[0023] In a possible implementation, the inner diameter of the steel needle used when the spinning solution is electrospun in an electrospinning machine is 0.5-0.7 mm.

[0024] In a possible implementation, in step S4, the voltage applied when the spinning solution is electrospun in the electrospinning machine is 18-24 kV.

[0025] In a possible implementation, in step S4, the spinning rate applied when the spinning solution is electrospun in the electrospinning machine is 0.1-0.5 mL / h.

[0026] In a possible implementation, in step S4, the rotation speed of the collecting roller applied when the spinning solution is electrospun in the electrospinning machine is 400-800 rpm.

[0027] In a possible implementation, in step S4, when the spinning solution is electrospun in the electrospinning machine, the distance between the steel needle and the collecting roller is 10-15 cm.

[0028] The beneficial effects of the technical solution provided by this application include at least:

[0029] (1) The eggshell membrane used in this application is a waste in the environment. It is non-toxic, cheap and the most abundant biological waste. The various proteins in the eggshell membrane are used as natural biological materials to achieve waste recycling, reflecting the concept of resource recycling and green environmental protection;

[0030] (2) The PEO polymer used in this application has the advantages of good water solubility, low toxicity, easy processing and molding, a wide range of molecular weight variations, and the ability to form complexes with a variety of organic low molecular weight compounds and certain inorganic electrolytes, which can improve the spinning performance of the spinning solution and improve the comprehensive performance of the fiber membrane;

[0031] (3) The present application uses electrospinning technology to prepare a fiber membrane with a nanostructure in one step. By applying a high-voltage electrostatic field, the porous thin layer and highly collagenized fiber membrane structure of the eggshell membrane are reorganized in an orderly manner, so that the fibers in the fiber membrane have good orientation and have certain flexibility and strength, thereby increasing the overall stability of the fiber membrane;

[0032] (4) The preparation method provided in the present application is simple and the raw materials are readily available. By blending PEO polymer with eggshell membrane, the viscosity of the spinning solution is enhanced and the toughness of the fiber membrane is improved. The obtained fiber membrane is not brittle, the fiber diameter and distribution are uniform, it has good biocompatibility and degradability, and contains many bioactive substances, which play an important role in moisturizing, anti-wrinkle and improving metabolism of the skin. The larger fiber specific surface area also enhances the adsorption capacity of the nanofiber membrane. Medical bandages, socks, pillows and other textile products are prepared through textile technology and applied in the textile field, which can achieve good effects of absorbing odor, sterilizing and deodorizing, and promoting skin metabolism. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings:

[0034] Figure 1 A schematic flow chart of a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material provided by an exemplary embodiment of the present application is shown;

[0035] Figure 2 A schematic flow chart of another method for preparing a nanofiber membrane using waste eggshell inner membrane as a raw material provided by an exemplary embodiment of the present application is shown;

[0036] Figure 3 shows the microstructure of eggshell membrane under field emission scanning electron microscope;

[0037] Figure 4 shows a Fourier transform infrared spectrum of eggshell membrane;

[0038] Figure 5 The microstructures of five nanofiber membranes prepared in Examples 3 to 7 under a field emission scanning electron microscope are shown. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0041] First, a brief introduction is given to the terms involved in the embodiments of the present application:

[0042] PEO, also known as polyethylene oxide, is a high molecular polymer with the appearance of small white granular powder. It has good water solubility, high viscosity, and good lubricity. Even a small amount of addition can show good fiber dispersion effect.

[0043] Embodiment 1

[0044] Figure 1 A schematic flow chart of a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material provided by an exemplary embodiment of the present application is shown, the method comprising:

[0045] Step S1, pre-treating waste eggshell membranes to obtain eggshell membrane powder;

[0046] Step S2, dissolving the eggshell membrane powder obtained in step S1 in an aqueous solution and stirring until fully dissolved to obtain an eggshell membrane aqueous solution;

[0047] Step S3, adding PEO polymer to the eggshell membrane aqueous solution obtained in step S2 and stirring the mixture sufficiently to obtain a spinning solution;

[0048] Step S4, electrospinning the spinning solution obtained in step S3 in an electrospinning machine to obtain a nanofiber membrane using the waste eggshell inner membrane as a raw material.

[0049] Optionally, the molecular weight of the PEO polymer in step S3 is 400,000-900,000.

[0050] Furthermore, the mass ratio of PEO to eggshell membrane powder in the spinning solution obtained in step S3 is 1:3-3:1.

[0051] Preferably, in step S4, the inner diameter of the steel needle used when the spinning solution is electrospun in the electrospinning machine is 0.5-0.7 mm.

[0052] Optionally, in step S4, the voltage applied when the spinning solution is electrospun in the electrospinning machine is 18-24 kV.

[0053] In one example, in step S4, the spinning rate applied when the spinning solution is electrospun in the electrospinning machine is 0.1-0.5 mL / h.

[0054] Furthermore, in step S4, the rotation speed of the collecting roller applied when the spinning solution is electrospun in the electrospinning machine is 400-800 rpm.

[0055] As a preferred embodiment, in step S4, when the spinning solution is electrospun in the electrospinning machine, the distance between the steel needle and the collecting roller is 10-15 cm.

[0056] In summary, the above-mentioned method for preparing nanofiber membrane with waste eggshell inner membrane as raw material enhances the viscosity of the spinning solution and improves the toughness of the fiber membrane by blending PEO polymer with eggshell membrane. The fiber membrane is not easy to be brittle, the fiber diameter and distribution are uniform, it has good biocompatibility and degradability, and contains many biologically active substances, which play an important role in moisturizing, anti-wrinkle, and improving metabolism of the skin. The larger fiber specific surface area also enhances the adsorption capacity of the nanofiber membrane. Medical bandages, socks, pillows and other textile products are prepared through textile processing and applied in the textile field, which can achieve good effects of absorbing odor, sterilizing and deodorizing, and promoting skin metabolism.

[0057] Embodiment 2

[0058] Figure 2 A schematic flow chart of another method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material provided by an exemplary embodiment of the present application is shown, which includes three major steps:

[0059] (1) Pretreatment of discarded eggshell membranes: breaking fresh eggs and clearing white albumin; then thoroughly washing the eggshells with ultrapure deionized water for several times, peeling off the eggshell membranes from the eggshells; washing the eggshell membranes with ethanol and deionized water to remove trace albumin, wherein the concentration of ethanol is controlled at about 50%; drying the eggshell membranes in a drying oven for 30 minutes to prepare powder, wherein the temperature of the drying oven is set in the range of 60-80°C.

[0060] (2) Preparation of electrospinning solution: Dried eggshell membrane powder and PEO (polyethylene oxide) are added to an aqueous solution to prepare an eggshell membrane / PEO blend; the spinnability of the spinning solution is improved by controlling the weight ratio of PEO to eggshell membrane and the solution concentration.

[0061] (3) Preparation of nanofiber membrane: The prepared electrospinning stock solution is filled into a syringe equipped with a steel needle and spun using an electrospinning machine; the uniformity of fiber diameter and distribution in the nanofiber membrane is improved by controlling parameters such as spinning flow rate, voltage, collection roller speed, and temperature and humidity; after spinning, the aluminum foil with the formed membrane is removed from the collection roller and left for 24 hours to remove residual organic solvent and moisture, thereby finally obtaining a nanofiber membrane made from discarded eggshell inner membrane.

[0062] It is worth mentioning that Figure 3 The microstructure of the eggshell membrane under a field emission scanning electron microscope is shown. It can be seen from the figure that the surface of the eggshell membrane shows a dense microfiber cross-linked network structure, which provides large gaps and a high specific surface area, thereby forming an effective contact area under pressure.

[0063] It is worth mentioning that Figure 4 The Fourier transform infrared spectrum of the eggshell membrane is shown. In the FT-IR spectrum of the eggshell membrane, various strong absorption and vibration peaks centered at 1630, 1523, and 1233 cm-1 appear due to the presence of amide I band, amide II band, and amide III band, which are respectively produced by C=O stretching or hydrogen bonding and COO-coupling, NH bending, CN stretching, and NH bending vibration coupling. The peak appearing at 1447 cm-1 is C=C stretching, and the peak at 1078 cm-1 is assigned to CO stretching vibration. The absorption peak at 930 cm-1 is attributed to HCH rocking vibration. These all reflect the characteristic peaks of proteins in the eggshell membrane.

[0064] In summary, the above-mentioned method for preparing nanofiber membrane with waste eggshell inner membrane as raw material enhances the viscosity of the spinning solution and improves the toughness of the fiber membrane by blending PEO polymer with eggshell membrane. The fiber membrane is not easy to be brittle, the fiber diameter and distribution are uniform, it has good biocompatibility and degradability, and contains many biologically active substances, which play an important role in moisturizing, anti-wrinkle, and improving metabolism of the skin. The larger fiber specific surface area also enhances the adsorption capacity of the nanofiber membrane. Medical bandages, socks, pillows and other textile products are prepared through textile processing and applied in the textile field, which can achieve good effects of absorbing odor, sterilizing and deodorizing, and promoting skin metabolism.

[0065] Embodiment 3

[0066] This embodiment provides a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, and the specific steps are as follows:

[0067] (1) Pretreatment of discarded eggshell membranes: fresh eggs were broken and the white albumin was removed by blunt end treatment. The eggshells were then thoroughly washed several times with ultrapure deionized water, and the inner eggshell membrane was carefully peeled off from the eggshell. The inner eggshell membrane was washed with ethanol and deionized water to remove trace albumin. The eggshell membrane was dried in a drying oven at 60°C for 30 minutes and then powdered.

[0068] (2) Preparation of electrospinning solution: Dried eggshell membrane powder and PEO

[0069] (400000 g / mol) was directly added to an aqueous solution (30 ml) to prepare an eggshell membrane / poly(ethylene oxide) (PEO) blend, wherein the weight ratio of PEO to eggshell membrane was 1:1, resulting in a 13.3 wt % eggshell membrane / PEO solution.

[0070] (3) Preparation of electrospinning fiber membrane: The electrospinning equipment used in this study was produced by Dalian Tesman Technology Co., Ltd.; During the electrospinning process, the prepared electrospinning solution was filled into a 10 mL syringe equipped with a 19-gauge steel needle (needle inner diameter of 0.5 mm); After removing the bubbles in the syringe, the syringe was fixed on a syringe pump (Pfeder, model: 57BYG250B-8); the steel needle was connected to a TCM6002 high-voltage DC power supply through a tungsten electrode; a 20 kV potential was applied to the tip of the injection needle; the distance between the steel needle and the collection roller (grounded aluminum foil) was about 10 cm; the applied spinning flow rate was 0.06 mL / h. The rotating collection roller rotated at a speed of 400 rpm; the spinning temperature was 22°C-24°C, and the relative humidity was 45%-50%; after electrospinning, the aluminum foil with the forming pad was immediately removed from the collection roller and placed in a hood for 24 hours to remove residual organic solvents and moisture.

[0071] Embodiment 4

[0072] This embodiment provides a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, and the specific steps are as follows:

[0073] (1) Pretreatment of discarded eggshell membranes: fresh eggs were broken and the white albumin was removed by blunt end treatment; the eggshells were then thoroughly washed several times with ultrapure deionized water, and the inner eggshell membrane was carefully peeled off from the eggshell; the inner eggshell membrane was washed with ethanol and deionized water to remove trace albumin; the eggshell membrane was dried in a drying oven at 60°C for 30 minutes and then powdered.

[0074] (2) Preparation of electrospinning solution: Dried eggshell membrane powder and PEO

[0075] (400000 g / mol) was directly added to an aqueous solution (30 ml) to prepare an eggshell membrane / poly(ethylene oxide) (PEO) blend, wherein the weight ratio of PEO to eggshell membrane was 1:2, respectively, resulting in a 13.3 wt % eggshell membrane / PEO solution.

[0076] (3) Preparation of electrospinning fiber membrane: The electrospinning equipment used in this study was produced by Dalian Tesman Technology Co., Ltd.; during the electrospinning process, the prepared electrospinning solution was filled into a 10 mL syringe equipped with a 19-gauge steel needle (needle inner diameter of 0.5 mm); after removing the bubbles in the syringe, the syringe was fixed on a syringe pump (Pfeder, model: 57BYG250B-8); the steel needle was connected to a TCM6002 high-voltage DC power supply through a tungsten electrode; a potential of 22 kV was applied to the tip of the injection needle; the distance between the steel needle and the collecting roller (grounded aluminum foil) was about 10 cm; the applied spinning flow rate was 0.06 mL / h; the rotating collecting roller rotated at a speed of 400 rpm; the spinning temperature was 22°C-24°C, and the relative humidity was 45%-50%; after electrospinning, the aluminum foil with the forming pad was immediately removed from the collecting roller and placed in a hood for 24 hours to remove residual organic solvents and moisture.

[0077] Embodiment 5

[0078] This embodiment provides a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, and the specific steps are as follows:

[0079] (1) Pretreatment of discarded eggshell membranes: Break fresh eggs and remove white albumin with a blunt end; then wash the eggshells thoroughly with ultrapure deionized water several times, and carefully peel off the inner eggshell membrane from the eggshell. Wash the inner eggshell membrane with ethanol and deionized water to remove trace albumin; dry the eggshell membrane in a drying oven at 60°C for 30 minutes and make it into powder.

[0080] (2) Preparation of electrospinning solution: Dried eggshell membrane powder and PEO

[0081] (400000 g / mol) was directly added to an aqueous solution (30 ml) to prepare an eggshell membrane / poly(ethylene oxide) (PEO) blend, wherein the weight ratio of PEO to eggshell membrane was 1:3, respectively, resulting in a 13.3 wt % eggshell membrane / PEO solution.

[0082] (3) Preparation of electrospinning fiber membrane: The electrospinning equipment used in this study was produced by Dalian Tesman Technology Co., Ltd.; During the electrospinning process, the prepared electrospinning solution was filled into a 10 mL syringe equipped with a 19-gauge steel needle (needle inner diameter of 0.5 mm); After removing the bubbles in the syringe, the syringe was fixed on a syringe pump (Pfeder, model: 57BYG250B-8); the steel needle was connected to a TCM6002 high-voltage DC power supply through a tungsten electrode; a 25 kV potential was applied to the tip of the injection needle; the distance between the steel needle and the collection roller (grounded aluminum foil) was about 10 cm. The applied spinning flow rate was 0.06 mL / h; the rotating collection roller rotated at a speed of 400 rpm; the spinning temperature was 22°C-24°C, and the relative humidity was 45%-50%; after electrospinning, the aluminum foil with the forming pad was immediately removed from the collection roller and placed in a hood for 24 hours to remove residual organic solvents and moisture.

[0083] Embodiment 6

[0084] This embodiment provides a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, and the specific steps are as follows:

[0085] (1) Pretreatment of discarded eggshell membranes: fresh eggs were broken and the white albumin was removed by blunt end treatment; the eggshells were then thoroughly washed several times with ultrapure deionized water, and the inner eggshell membrane was carefully peeled off from the eggshell; the inner eggshell membrane was washed with ethanol and deionized water to remove trace albumin; the eggshell membrane was dried in a drying oven at 60°C for 30 minutes and then powdered.

[0086] (2) Preparation of electrospinning solution: Dried eggshell membrane powder and PEO

[0087] Eggshell membrane / poly(ethylene oxide) (PEO) blends were prepared by directly adding PEG (400,000 g / mol) into an aqueous solution (30 ml), wherein the weight ratio of PEO to eggshell membrane was 2:1, respectively, to produce a 13.3 wt % eggshell membrane / PEO solution.

[0088] (3) Preparation of electrospinning fiber membrane: The electrospinning equipment used in this study was produced by Dalian Tesman Technology Co., Ltd.; during the electrospinning process, the prepared electrospinning solution was filled into a 10 mL syringe equipped with a 19-gauge steel needle (needle inner diameter of 0.5 mm); after removing the bubbles in the syringe, the syringe was fixed on a syringe pump (Pfeder, model: 57BYG250B-8); the steel needle was connected to a TCM6002 high-voltage DC power supply through a tungsten electrode; an electric potential of 18 kV was applied to the tip of the injection needle; the distance between the steel needle and the collecting roller (grounded aluminum foil) was about 10 cm; the applied spinning flow rate was 0.06 mL / h; the rotating collecting roller rotated at a speed of 400 rpm; the spinning temperature was 22°C-24°C, and the relative humidity was 45%-50%; after electrospinning, the aluminum foil with the forming pad was immediately removed from the collecting roller and placed in a hood for 24 hours to remove residual organic solvents and moisture.

[0089] Embodiment 7

[0090] This embodiment provides a method for preparing a nanofiber membrane using waste eggshell inner membrane as raw material, and the specific steps are as follows:

[0091] (1) Pretreatment of discarded eggshell membranes: fresh eggs were broken and the white albumin was removed by blunt end treatment; the eggshells were then thoroughly washed several times with ultrapure deionized water, and the inner eggshell membrane was carefully peeled off from the eggshell; the inner eggshell membrane was washed with ethanol and deionized water to remove trace albumin; the eggshell membrane was dried in a drying oven at 60°C for 30 minutes and then powdered.

[0092] (2) Preparation of electrospinning solution: Dried eggshell membrane powder and PEO

[0093] (400000 g / mol) was directly added to an aqueous solution (30 ml) to prepare an eggshell membrane / poly(ethylene oxide) (PEO) blend, wherein the weight ratio of PEO to eggshell membrane was 3:1, respectively, resulting in a 13.3 wt % eggshell membrane / PEO solution.

[0094] (3) Preparation of electrospinning fiber membrane: The electrospinning equipment used in this study was produced by Dalian Tesman Technology Co., Ltd.; During the electrospinning process, the prepared electrospinning solution was filled into a 10 mL syringe equipped with a 19-gauge steel needle (needle inner diameter of 0.5 mm); After removing the bubbles in the syringe, the syringe was fixed on a syringe pump (Pfeder, model: 57BYG250B-8); the steel needle was connected to a TCM6002 high-voltage DC power supply through a tungsten electrode; a 16 kV potential was applied to the tip of the injection needle; the distance between the steel needle and the collection roller (grounded aluminum foil) was about 10 cm; the applied spinning flow rate was 0.06 mL / h; the rotating collection roller rotated at a speed of 400 rpm; the spinning temperature was 22°C-24°C, and the relative humidity was 45%-50%. After electrospinning, the aluminum foil with the forming pad was immediately removed from the collection roller and placed in a hood for 24 hours to remove residual organic solvents and moisture.

[0095] Effect verification

[0096] Figure 5 The microstructure diagrams of the five nanofiber membranes prepared in the above-mentioned Examples 3 to 7 under a field emission scanning electron microscope are shown, wherein (a), (b), (c), (d) and (e) are nanofiber membranes with a mass ratio of PEO to eggshell membrane of 1:1, 1:2, 1:3, 2:1 and 3:1, respectively. It can be seen that when the mass ratio of PEO to eggshell membrane is 2:1, the fiber presents a good morphology, the fiber diameter is relatively uniform, the structure is relatively dense, and the fiber has a large specific surface area. However, if the eggshell membrane or PEO content is too much, the viscosity of the spinning solution will be too low or too high, so that the fibers in the fiber membrane cannot be filamented into single strands, and more adhesion occurs, which reduces the flatness and uniformity of the fibers.

[0097] In summary, the eggshell membrane used in this application belongs to the waste in the environment, which is non-toxic, cheap and the most abundant biological waste. Using various proteins in eggshell membrane as natural biological materials, waste recycling is realized, reflecting the concept of resource recycling and green environmental protection; the PEO polymer used has the advantages of good water solubility, low toxicity, easy processing and molding, wide range of molecular weight variation, and can form complexes with various organic low molecular compounds and certain inorganic electrolytes, which can improve the spinning performance of the spinning solution and improve the comprehensive performance of the fiber membrane; the fiber membrane with nanostructure is prepared in one step by electrospinning technology, and the porous thin layer and highly collagenized fiber membrane structure of the eggshell membrane itself are re-ordered by applying a high-voltage electrostatic field, so that the fibers in the fiber membrane have good orientation, and have certain flexibility and strength, increasing the overall stability of the fiber membrane. The preparation method of the nanofiber membrane is simple and the raw materials are easily available. By blending PEO polymer with eggshell membrane, the viscosity of the spinning solution is enhanced and the toughness of the fiber membrane is improved. The obtained fiber membrane is not easy to be brittle, the fiber diameter and distribution are uniform, it has good biocompatibility and degradability, and contains many bioactive substances, which play an important role in moisturizing, anti-wrinkle and improving metabolism of the skin. The larger fiber specific surface area also enhances the adsorption capacity of the nanofiber membrane. Medical bandages, socks, pillows and other textile products are prepared through textile technology and applied to the textile field, which can achieve good effects of absorbing odor, removing bacteria and deodorizing, and promoting skin metabolism.

[0098] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for preparing nanofiber membranes under high eggshell membrane / PEO content conditions, characterized in that: The method comprises the following steps: S1. Break a fresh egg and remove the albumin by blunt end; then wash the eggshell thoroughly with ultrapure deionized water for several times, and peel off the eggshell membrane from the eggshell; then wash the eggshell membrane with 40-60% ethanol and deionized water to remove trace albumin; dry the eggshell membrane in a drying oven at 60° C. for 30 minutes and then make it into powder to obtain eggshell membrane powder; S2, adding PEO and the eggshell membrane powder obtained in step S1 to 30 ml of aqueous solution to prepare an eggshell membrane / PEO solution, i.e., a spinning solution; The weight ratio of PEO to eggshell membrane powder is 2:1, the concentration of PEO in the spinning solution is 400000 g / mol, and the concentration of eggshell membrane / PEO in the eggshell membrane / PEO solution is 13.3 wt%; S3, the spinning solution obtained in step S2 is filled into a 10mL syringe equipped with a No. 19 steel needle, the inner diameter of the steel needle is 0.5mm; after removing the bubbles in the syringe, the syringe is fixed on the syringe pump; the steel needle is connected to a TCM6002 high-voltage DC power supply through a tungsten electrode; an electric potential of 18kV is applied to the tip of the injection needle; the distance between the steel needle and the collecting roller is about 10cm, and the collecting roller is a grounded aluminum foil; the spinning flow rate applied is 0.06mL / h; the rotating collecting roller rotates at a speed of 400rpm; the spinning temperature is 22℃-24℃, and the relative humidity is 45%-50%; after electrospinning, the aluminum foil with the forming pad is immediately removed from the collecting roller and placed in a cover for 24 hours to remove residual organic solvents and moisture, and finally a nanofiber membrane with increased eggshell membrane / PEO concentration, reduced fiber fineness of the nanofiber membrane and uniform nanofiber membrane structure is obtained.

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