CN105803676A - Preparation method of keratin/PEO nanofiber membrane with high keratin content - Google Patents

Abstract

The invention provides a preparation method of a keratin/PEO nanofiber membrane with high keratin content. The method comprises the specific steps that a keratin solution extracted from natural keratin fibers by adopting a reduction method and PEO powder are blended according the keratin/PEO mass ratio of 95-90 to 5-10, then ethylene glycol diglycidyl ether is added to the mixed solution to obtain a spinning solution having good spinnability through crosslinking, and then the nanofiber membrane is prepared by adopting an electrostatic spinning technique. The nanofiber membrane is suspended in hot air of 120-140 DEG C for thermal crosslinking, and accordingly the water-insoluble keratin/PEO nanofiber membrane with the high keratin content is obtained. The keratin/PEO nanofiber membrane has wide application prospect on the aspect of biomedical science.

Description

A kind of preparation method of keratin/PEO nanofibrous film with high keratin content

technical field

The invention provides a method for preparing a keratin/PEO nanofiber membrane with a high proportion of keratin content, and belongs to the technical field of biomaterials.

Background technique

Natural keratin fibers widely exist in human and animal skin and skin derivatives, but most of them are directly discarded or burned as garbage, which not only causes a large waste of keratin resources, but also seriously pollutes the environment and causes harm to humans . Therefore, the development and utilization of natural keratin fibers has huge economic and social benefits.

Keratin is a fibrous protein, the basic composition is amino acids, amino acids form polypeptide chains through peptide bonds, and polypeptide chains form the spatial configuration of keratin through disulfide bonds, hydrogen bonds, salt bonds and van der Waals forces. Make keratin a tortuous and cross-linked helical three-dimensional structure, which is complex and dense. Due to the unique molecular structure of keratin, keratin materials have excellent biological properties. High molecular weight keratin has good biodegradability and biocompatibility. Therefore, keratin and its modified products have good application prospects in the field of biomaterials.

In 2004, Japanese scholar Yamauchi Kiyomi used sodium bisulfite as a reducing agent to extract keratin, then mixed keratin with PVA, and used water as a solvent to prepare keratin/PVA blended fiber filaments by wet spinning technology (Preparation and Properties of Keratin-Poly (vinyl alcohol) Blend Fiber, Journal of Applied Polymer Science, Vol. 91, 2004: 756-762). The report uses water as a solvent to achieve the purpose of environmental protection, and at the same time proposes that heat treatment can properly improve the water solubility of blended fiber filaments.

In 2008, Chinese scholar Yuan Jiang et al. used mercaptoethanol as a reducing agent to extract keratin, modified it with iodoacetic acid and dissolved it in hexafluoroisopropanol with PHBV in different proportions, prepared nanofibers by electrospinning technology, and made nanofibers Fibers were used to culture NIH3T3 cells (Fabrication of PHBV/Keratin Composite Nanofibrous Mats for Biomedical Applications, Macromolecular Research, Vol. 17, 2009: 850-855). The results showed that PHBV could improve the spinnability of keratin, and keratin/PHBV nanofibers were beneficial for cell adhesion and reproduction.

In 2008, scholar Alessio Varesano et al. used sulfite as a reducing agent to extract wool keratin, blended with PEO and prepared keratin/PEO nanofibers by electrospinning technology with water as a solvent, and obtained a keratin/PEO mass ratio of 70/30 keratin/PEO nanofibres (Structure and properties of keratin/PEO blendnanofibres, European Polymer Journal, Vol. 44, 2008: 2465-2475). However, when the proportion of keratin content is further increased, a large number of beads appear on the fiber, and the quality of the silk is reduced.

Xing Zhicai et al. used trifluoroethanol as a solvent to prepare keratin/PEO nanofibers, and obtained keratin/PEO blended nanofibers with a keratin/PEO mixing ratio of 90:10, (Keratin Nanofibers as a Biomaterial, International Conference on Nanotechnology and Biosensors, IPCBEE Vol.2, 2011: 120-124). However, the organic solvent used in the preparation of the spinning solution by this method has strong irritation, which causes serious pollution to the human body and the environment, and the price of the organic solvent is also very expensive.

Fan Jie et al. used a two-step cross-linking method to prepare keratin/PEO nanofibers with a high proportion of keratin content using water as a solvent (CN 104264369 A). The human hair keratin extracted with sulfite as a reducing agent was blended with PEO, the spinning solution was prepared with water as a solvent, and the spinning solution was cross-linked by a cross-linking agent and then electrospun to successfully prepare a keratin/PEO blend. Keratin/PEO nanofibers with high keratin content in the ratio of 90/10, and then post-crosslinking the nanofibers under pure oxygen conditions to obtain water-insoluble keratin/PEO nanofibers, the two-step crosslinking method improved Spinnability of keratin/PEO spinning dopes with high proportion of keratin content in water as solvent.

Italian scholar Annalisa Aluigi et al. freeze-dried keratin extracted from sodium metabisulfite to obtain keratin powder, and then used formic acid as a solvent to successfully prepare pure keratin nanofibers through spinning equipment on a self-assembled receiving device. At the same time, it was found that the nanofibers had good water resistance after formaldehyde steam crosslinking and thermal crosslinking (Morphological and structural investigation of wool-derived keratin nanofibres crosslinked by thermal treatment, International Journal of Biologieal Macromolecules, Vol.57, 2013: 30-37 ).

The above patents and literature reports have reported keratin regenerated fibers from different aspects. Generally speaking, when preparing keratin nanofibers under the condition of using water as a solvent, keratin needs to be mixed with other polymers due to poor spinnability of keratin. Therefore, there is a bottleneck in the preparation of nanofibers with a high proportion of keratin content in this method; when using organic solvents to prepare protein nanofibers, the keratin can be improved by modifying keratin. Dispersion in organic solvents, thereby increasing the content of keratin in blended nanofibers, and even realizing purely spun keratin nanofibers, but there are defects such as high cost of organic solvents and serious pollution.

Therefore, from the perspective of environmental protection and low cost, the present invention increases the content of high-proportion keratin by adopting a keratin extraction method with a small degree of damage to keratin macromolecules and combining the method of cross-linking keratin in the spinning solution. The spinnability of the keratin blended spinning solution is high, and the keratin blended nanofibers with a keratin content higher than 90% are spun, and the water resistance of the nanofiber film is improved by thermal cross-linking treatment, and the water-insoluble, high-ratio Keratin/PEO bionanofiber membranes with keratin content. The method has the characteristics of environmental protection, low energy consumption and low cost. The prepared keratin/PEO bionanofibrous membrane with a high proportion of keratin content has wide applications in the field of biomedicine.

Contents of the invention

The object of the present invention is to provide a method for preparing a keratin/PEO nanofiber film with a high proportion of keratin content.

In order to achieve the above object, the technical solution of the present invention is to blend the keratin concentrated solution extracted from the waste natural keratin fiber by reduction method with PEO powder according to the mass percentage of keratin/PEO 95-90:5-10 to obtain keratin /PEO mixed solution, adding ethylene glycol diglycidyl ether to the mixed solution to cross-link to obtain a spinning solution with good spinnability, and then prepare a keratin/PEO nanofiber film by electrospinning technology, and pass the film through Thermal cross-linking to prepare water-insoluble keratin/PEO bionanofiber membranes with a keratin content of 90-95%.

The concrete technical scheme that the keratin solution of the present invention extracts is:

Step 1: Open and remove impurities from natural keratin fibers and cut them into 5-10mm fiber segments, then use petroleum ether to remove impurities such as grease, wash with deionized water, and dry naturally;

The second step: immerse the above-mentioned natural keratin fiber into the solution of PH=9.0 containing reducing agent, protein denaturing agent and surfactant at a solid-to-liquid ratio of 12-16g/250ml, and stir at 60-80°C for 4 -12h, the stirrer speed is 200-400r/min;

Step 3: Filter the stirred mixture with a 80-150 mesh screen to remove undissolved natural keratin fibers, and dialyze the filtered keratin salt solution at room temperature to remove salt and small molecular substances in the solution ;

Step 4: Centrifuge the keratin obtained by dialysis to remove the precipitated part in the dialysate, the centrifugation speed is 5000-7000rpm, the centrifugation time is 0.2-1h, and then take the supernatant;

Step 5: Concentrating the supernatant to obtain a concentrated keratin solution with a concentration of 10-14% by mass.

The discarded natural keratin fibers are discarded cow hair, wool, pig hair, human hair, rabbit hair or poultry feathers and the like.

The reducing agent is 2-mercaptoethanol (also known as β-mercaptoethanol), dithiothreitol, thioglycolic acid, etc., and the mass percent concentration of the reducing agent is 4%-7%.

The keratin denaturant is urea, thiourea or lithium bromide, and the mass percent concentration of the protein denaturant is 18-25%.

The surfactant is sodium lauryl sulfate, and the mass percent concentration of the surfactant is 1-5%.

The cross-linking is to use ethylene glycol diglycidyl ether with a concentration of 1.86-6.21% by mass to cross-link the keratin in the spinning solution. The cross-linking method is as follows: under the condition of 50-65 DEG C, evenly add ethylene glycol diglycidyl ether dropwise to the spinning solution while stirring to cross-link the keratin/PEO mixed spinning solution.

The electrospinning can adopt needle type, bubble type, disc type and other electrospinning methods. The spinning conditions are: under room temperature, an applied voltage of 16-30KV, a spinning receiving distance of 13-18cm, and a perfusion speed of 0.3 -1.0ml/h.

The thermal crosslinking is to place the keratin/PEO biological nanofiber membrane in hot air at 120-140° C. for thermal crosslinking.

Description of drawings

Fig. 1 is the keratin/PEO (90/10) nanofiber membrane of primary crosslinking, the mass ratio concentration of spinning solution is 13%, the concentration of primary crosslinking crosslinking agent is 3%.

Fig. 2 is an uncrosslinked keratin/PEO (95/5) nanofiber membrane, and the mass ratio concentration of the spinning solution is 13%.

Fig. 3 is the keratin/PEO (95/5) nanofiber membrane of primary crosslinking, the mass ratio concentration of spinning solution is 13%, the concentration of primary crosslinking crosslinking agent is 6.21%.

Fig. 4 is the keratin/PEO (95/5) nanofiber film after thermal crosslinking, and the mass ratio concentration of spinning solution is 13%, and initial crosslinking crosslinking agent concentration is 6.21%, and 120 ℃ thermal crosslinking time is 2h.

Fig. 5 is the heat-crosslinked keratin PEO (95/5) nanofiber film after soaking in distilled water, the mass ratio concentration of spinning solution is 13%, the initial crosslinking crosslinking agent concentration is 6.21%, 120 ℃ thermal crosslinking 2h, soak in water for 72h.

detailed description

The present invention is specifically described below through examples.

Example 1

After the human hair fiber is opened, cleaned, cleaned and dried in sequence, it is cut into 5-10mm fiber segments, and then immersed in a PH of 9 at a solid-to-liquid ratio of 13g/250ml, containing reducing agents and protein denaturants. The solution was stirred at 65° C. for 12 hours, and the rotation speed of the stirrer was 200 r/min. Wherein the reducing agent is mercaptoethanol, and the mass specific concentration is 4% of the solution; the protein denaturant is urea, and the mass specific concentration is 24% of the solution. The mixed solution after stirring was filtered with 80 mesh screens to remove unreacted fibers, then dialyzed in distilled water containing 0.1% mercaptoethanol for 36 hours to remove small molecular substances, and centrifuged to remove precipitated substances. The centrifugal speed was 7000rpm and the centrifugation time was 0.25h. Take the supernatant. Concentrate the obtained supernatant to obtain a pure keratin solution with a mass ratio concentration of 10%.

Add PEO powder and an appropriate amount of distilled water to the keratin solution with a mass ratio concentration of 10%, so that the mass ratio of keratin/PEO is 90/10, stir at a temperature of 45°C until the PEO powder is completely dissolved, and mix with keratin The solution is mixed evenly to obtain a mixed spinning solution with a mass ratio concentration of 11%, and then ethylene glycol diglycidyl ether is added dropwise to the spinning solution, and the mass percentage of ethylene glycol diglycidyl ether is 1.68% of that of the spinning solution. %, after stirring evenly for 30 minutes, it was added to needle electrospinning equipment to prepare keratin/PEO nanofiber membranes. Electrospinning for a period of time yielded keratin/PEO nanofibrous membranes. The above-mentioned keratin/PEO nanofiber membrane was suspended in hot air at a temperature of 120° C. for 4 h to be cross-linked.

Example 2

After opening, removing impurities, cleaning and drying the rabbit hair fibers in sequence, cut them into 5-10mm fiber segments, and then immerse them in a PH of 9 with a solid-to-liquid ratio of 12g/250ml, containing reducing agents and protein denaturants. The solution was stirred at 60° C. for 14 h, and the rotation speed of the stirrer was 250 r/min. Wherein the reducing agent is thioglycolic acid, and the mass specific concentration is 5% of the solution; the protein denaturant is thiourea, and the mass specific concentration is 25% of the solution. The stirred mixed solution was filtered with a 100-mesh sieve to remove unreacted fibers, then dialyzed in distilled water containing 0.1% mercaptoethanol for 48 hours to remove small molecular substances, and centrifuged to remove precipitated substances. The centrifugal speed was 6500 rpm and the centrifugal time was 0.3 hours. Take the supernatant. The obtained supernatant was concentrated to obtain a pure keratin solution with a mass ratio concentration of 12%.

Add PEO powder and an appropriate amount of distilled water to the keratin solution with a mass ratio concentration of 12%, so that the mass ratio of keratin/PEO is 92/8, stir at a temperature of 50°C until the PEO powder is completely dissolved, and mix with the keratin solution Mix evenly to obtain a mixed spinning solution with a mass ratio concentration of 12%, then add ethylene glycol diglycidyl ether dropwise to the spinning solution, and the mass percentage of ethylene glycol diglycidyl ether is 2.48% of the spinning solution , after stirring evenly for 30 minutes, put it into the needle electrospinning equipment to prepare keratin/PEO nanofiber membrane. A keratin/PEO nanofibrous membrane is obtained by spinning for a period of time. The above-mentioned keratin/PEO nanofiber membrane was suspended in hot air at a temperature of 130° C. for 3 h to be cross-linked.

Example 3

After the pig hair fiber is opened, cleaned, cleaned and dried in sequence, it is cut into 5-10mm fiber segments, and then immersed in a PH of 9 at a solid-to-liquid ratio of 14g/250ml, containing reducing agents and protein denaturants. In the solution, stir at 68°C for 10 hours, the rotation speed of the stirrer is 300r/min, wherein the reducing agent is dithiothreitol, and the mass ratio concentration is 4.5% of the solution; the protein denaturant is lithium bromide, and the mass ratio concentration is 4.5% of the solution. 25% of. The stirred mixed solution was filtered with a 150-mesh screen to remove unreacted fibers, then dialyzed in distilled water containing 0.1% mercaptoethanol for 72 hours to remove small molecular substances, and centrifuged to remove precipitated substances. The centrifugal speed was 6000rpm and the centrifugation time was 0.5h. Take the supernatant. The obtained supernatant was concentrated to obtain a pure keratin solution with a mass ratio concentration of 12.5%.

Add PEO powder and appropriate amount of distilled water to the keratin solution with a mass ratio concentration of 12.5%, so that the mass ratio of keratin/PEO is 94/6, stir at a temperature of 60°C until the PEO powder is completely dissolved, and mix with the keratin solution Mix evenly to obtain a mixed spinning solution with a mass ratio concentration of 12%. Then add ethylene glycol diglycidyl ether dropwise in the spinning solution, the mass percentage of ethylene glycol diglycidyl ether is 3.73% of the spinning solution, after uniform stirring for 30min, join in the needle type electrostatic spinning equipment, To prepare keratin/PEO nanofiber membrane, the specific operating conditions are: under normal temperature, applied voltage 20KV, receiving distance 15cm, perfusion speed 0.5ml/h, electrospinning for a period of time to obtain keratin/PEO nanofiber membrane. The above-mentioned keratin/PEO nanofiber membrane was suspended in hot air at a temperature of 140° C. for 2 h for crosslinking.

Example 4

After the chicken feather fibers are opened, removed, cleaned and dried in sequence, they are cut into 5-10mm fiber segments, and then immersed in a solution with a solid-to-liquid ratio of 16g/250ml and a pH of 9, containing reducing agents and protein denaturants , stirred at 80°C for 6h, and the rotation speed of the stirrer was 400r/min. Wherein the reducing agent is mercaptoethanol, and the mass specific concentration is 8% of the solution; the protein denaturant is thiourea, and the mass specific concentration is 20% of the solution. The stirred mixed solution was filtered with a 150-mesh screen to remove unreacted fibers, then dialyzed in distilled water containing 0.1% mercaptoethanol for 72 hours to remove small molecular substances, and centrifuged to remove precipitated substances. The centrifugal speed was 6000rpm and the centrifugation time was 0.5h. Take the supernatant. The obtained supernatant was concentrated to obtain a pure keratin solution with a mass ratio concentration of 13%.

Add appropriate amount of distilled water of PEO powder to the keratin solution with a mass ratio concentration of 13%, so that the mass ratio of keratin/PEO is 95/5, stir at a temperature of 50°C until the PEO powder is completely dissolved, and mix with the keratin solution Mix evenly to obtain a mixed spinning solution with a mass ratio concentration of 13%. Then add ethylene glycol diglycidyl ether drop by drop in the spinning solution, the mass percentage of ethylene glycol diglycidyl ether is 6.21% of the spinning solution, after uniform stirring for 30min, join in the needle type electrostatic spinning equipment, Preparation of keratin/PEO nanofiber membranes. The specific operating conditions are: under the condition of normal temperature, the applied voltage is 30KV, the receiving distance is 18cm, the perfusion speed is 0.8ml/h, and the keratin/PEO nanofiber membrane is obtained by electrospinning for a period of time. The above-mentioned keratin/PEO nanofiber membrane was suspended in hot air at a temperature of 140° C. for 2 h for crosslinking.

Example 5

After opening, removing impurities, cleaning and drying the bovine hair fibers in sequence, cut them into 5-10mm fiber segments, and then immerse them in a solution with a solid-to-liquid ratio of 10g/250ml in a solution containing a reducing agent and a protein denaturant at a pH of 9 , stirred at 75°C for 6h, and the rotation speed of the stirrer was 350r/min. Wherein the reducing agent is dithiothreitol, and the mass ratio concentration is 7% of the solution; the protein denaturant is urea, and the mass ratio concentration is 22% of the solution. The stirred mixed solution was filtered with a 100-mesh sieve to remove unreacted fibers, then dialyzed in distilled water containing 0.1% mercaptoethanol for 36 hours to remove small molecular substances, and centrifuged to remove precipitated substances at a centrifugal speed of 5000 rpm for 1 hour. supernatant. The obtained supernatant was concentrated to obtain a pure keratin solution with a mass ratio concentration of 12.5%.

Add PEO powder to the keratin solution with a mass ratio concentration of 12.5%, add an appropriate amount of distilled water to make the mass ratio of keratin/PEO 95/5, stir at a temperature of 50°C until the PEO powder is completely dissolved, and mix with horn The protein solution was evenly mixed to obtain a mixed spinning solution with a mass ratio concentration of 13%. Then add ethylene glycol diglycidyl ether dropwise in the spinning solution, the mass percentage of ethylene glycol diglycidyl ether is 4.97% of the spinning solution, after uniform stirring for 30min, join in the needle type electrostatic spinning equipment, To prepare keratin PEO nanofiber membrane, the specific operating conditions are: under normal temperature, applied voltage 25KV, receiving distance 15cm, perfusion speed 0.5ml/h, electrospinning for a period of time to obtain keratin/PEO nanofiber membrane. The above-mentioned keratin PEO nanofiber membrane was suspended in hot air at a temperature of 120° C. for 5 h to be cross-linked.

Example 6

After the human hair fiber is opened, cleaned, cleaned and dried in sequence, it is cut into 5-10mm fiber segments, and then immersed in a PH of 9 at a solid-to-liquid ratio of 14g/250ml, containing reducing agents and protein denaturants. The solution was stirred at 80° C. for 4 h, and the rotation speed of the stirrer was 200 r/min. Wherein the reducing agent is thioglycolic acid, and the mass specific concentration is 5% of the solution; the protein denaturant is thiourea, and the mass specific concentration is 25% of the solution. The stirred mixed solution was filtered with a 150-mesh screen to remove unreacted fibers, then dialyzed in distilled water containing 0.1% mercaptoethanol for 36 hours to remove small molecular substances, and centrifuged to remove precipitated substances at a centrifugal speed of 5000 rpm for 1 hour. supernatant. The obtained supernatant was concentrated to obtain a pure keratin solution with a mass ratio concentration of 13.5%.

Add PEO powder and an appropriate amount of distilled water to the keratin solution with a mass ratio concentration of 13.5%, so that the mass ratio of keratin/PEO is 93/7, stir at a temperature of 60°C until the PEO powder is completely dissolved, and mix with keratin The solutions were mixed uniformly to obtain a mixed spinning solution with a mass ratio concentration of 14%. Then add ethylene glycol diglycidyl ether drop by drop in the spinning solution, the mass percentage of ethylene glycol diglycidyl ether is 6.21% of the spinning solution, after uniform stirring for 30min, join in the needle type electrostatic spinning equipment, The specific operating conditions for preparing keratin PEO nanofiber membranes are: under normal temperature, applied voltage 28KV, receiving distance 18cm, perfusion speed 0.5ml/h, electrospinning for a period of time to obtain keratin/PEO nanofiber membranes. The above-mentioned keratin/PEO nanofiber membrane was suspended in hot air at a temperature of 120° C. for 2 h to be cross-linked.

Claims (9)

1. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion, it is characterised in that this is prepared Method be by the keratin concentrated solution extracted through reducing process by the natural keratin fiber discarded with PEO powder according to keratin / PEO mass percent 95-90: 5-10 is blended, and obtains keratin/PEO mixed solution, adds second two in this mixed solution The crosslinking of alcohol diglycidyl ether obtains the spinning liquid with good spinnability, then prepares keratin by electrostatic spinning technique / PEO nano fibrous membrane, by this film after heat cross-linking, obtains keratin/PEO that water-fast keratin content is 90-95% Biological nano fibrous membrane.

2. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levying and be, described discarded natural keratin fiber is discarded ox hair, Pilus Caprae seu Ovis, Crinis Carbonisatus, the rabbit hair, Pilus Sus domestica or camel hair etc..

3. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, its Being characterised by, described reducing process agents useful for same is reducing agent, keratinous degeneration agent and the compositions of surfactant, described Reducing agent be 2 mercapto ethanol (being also called beta-mercaptoethanol), dithiothreitol, DTT, TGA etc., the quality hundred of reducing agent Proportion by subtraction concentration is 4%-7%；Described keratinous degeneration agent is carbamide, thiourea or lithium bromide, the quality hundred of protein denaturant Proportion by subtraction concentration is 18-25%；Described surfactant is sodium lauryl sulphate, the mass percent concentration of surfactant For 1-5%.

4. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levying and be, concrete operation step is:

1. by cutting off into the segment of fiber of 5-10mm after natural keratin fiber shredding, remove impurity, then oils and fats is removed with petroleum ether Deng impurity, after deionized water is cleaned, naturally dry；

2. above-mentioned natural keratin fiber is immersed in containing reducing agent, protein denaturant with solid-to-liquid ratio for 12-16g/250ml With in the lysate of the PH=9.0 of surfactant, stirring 8-12h at a temperature of 60-70 DEG C, agitator speed is 200-400r/min；

3. mixture 80-150 eye mesh screen stirring obtained filters removes undissolved natural keratin fiber, at room temperature bar Under part, the keratin saline solution being filtrated to get is dialysed, remove the salt in solution and small-molecule substance；

4. the keratin obtained dialysis is centrifuged removing the sediment fraction in dialysis solution, and centrifugal speed is 5000-7000rpm, Centrifugation time 0.2-1h, then takes supernatant；

5. above-mentioned supernatant is concentrated, obtain the keratin concentrated solution that mass percent concentration is 10-14%.

5. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levying and be, the mass percent concentration of described keratin/PEO mixed solution is 11-14%.

6. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levy and be, described crosslinking be use mass percent concentration be that the Ethylene glycol diglycidyl ether of 1.68-6.21% is to spinning liquid In keratin cross-link.The method of crosslinking is: under conditions of 50-65 DEG C, the most uniform in spinning liquid while stirring Add Ethylene glycol diglycidyl ether keratin/PEO blend spinning liquid to cross-link.

7. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levying and be, described electrostatic spinning can use the electrospinning process such as needle-based, bubble type, disc type, and spinning condition is: Under room temperature condition, applied voltage 20-30KV, spinning receiving range 13-18cm, rate of flooding is 0.3-1.0ml/h.

8. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levying and be, described heat cross-linking is that keratin/PEO biological nano fibrous membrane is suspended in the hot-air of 120-140 DEG C and is carried out Heat cross-linking 2-6h.

9. the preparation method of the keratin/PEO nano fibrous membrane of keratin content at high proportion as claimed in claim 1, it is special Levying and be, the keratin content of the keratin/PEO nano fibrous membrane of the described content of keratin at high proportion is 90-95%.