Silk manufacturing method

Abstract

The invention discloses a silk production method, which comprises: (A) protein solution production: adding silkworm chrysalis powder or waste silk powder into an alkaline solution, heating for 4-5 h at a temperature of 90-95 DEG C, and filtering to obtain a protein solution with a protein content of 7-8%; (B) preparation of a polyacrylonitrile solution: adding polyacrylonitrile into a solvent, heating and dissolving to obtain the polyacrylonitrile solution; (C) preparing regenerated silk: mixing the protein solution obtained in the step (A) and the polyacrylonitrile solution obtained in the step (B) according to the proportion of (1-100): 100, uniformly stirring to form a spinning solution, and performing wet spinning on the spinning solution to obtain the regenerated silk. According to the invention, the low-cost silkworm pupa protein or waste silk powder is adopted, and the silkworm pupa protein and the silk protein in the silkworm pupa protein or the waste silk powder are re-linked to form the novel fiber, so that the regenerated silk fiber suitable for textiles and non-woven products is manufactured, and the price of the finished product of the silk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of textiles, and particularly to a method for making silk. Background Art

[0002] Silk is one of the natural proteins earliest utilized by humans. As a fiber with excellent properties, it is mainly applied in textiles. Recently, it has also been applied in many aspects such as biotechnology, medicine, and fine chemical engineering, attracting wide attention from people. There have been several monographs for summarization. Silk has a series of advantages such as high purity and wide sources, and has high strength and excellent elasticity. It is deeply favored by consumers because of its good hygroscopicity, soft handfeel, gorgeous appearance, and elegant luster, and is known as the "queen of fibers". At present, silk products belong to high-end consumer goods in the market. However, due to factors such as region, climate, labor force, and monomer output, the supply of silk has always been very small, with an annual supply of less than 20,000 tons. Due to limited supply and high recognition, there is a shortage in supply, and the price remains high, beyond the affordability of ordinary people.

[0003] Zhejiang Sci-Tech University and other units have carried out technological innovation to solve the problem of insufficient supply. By extracting proteins from waste silk recovered and recombining the proteins, however, the obtained silk fibers have very low strength and low heat-resistant temperature and cannot be dyed.

[0004] Therefore, a method for making silk is needed, which can recycle waste and the obtained silk also meets the usage requirements. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for making silk, which can achieve the purpose of reducing costs by recycling waste and obtaining silk with excellent properties, effectively alleviating the contradiction between supply and demand.

[0006] To solve the above technical problems, the present invention adopts the following technical solution: A method for making silk, comprising the following steps:

[0007] (A) Preparation of protein solution: Adding silkworm pupa powder or waste silk powder to an alkaline solution, heating at a temperature of 90 - 95 °C for 4 - 5 hours, and filtering to obtain a protein solution, wherein the protein content in the protein solution is in the range of 7 - 8%;

[0008] (B) Preparation of polyacrylonitrile solution: Adding polyacrylonitrile to a solvent and heating to dissolve it to obtain a polyacrylonitrile solution;

[0009] (C) Preparation of regenerated silk: Mixing the protein solution obtained in step (A) and the polyacrylonitrile solution obtained in step (B) according to a ratio of 1 - 100:100, and stirring evenly to form a spinning solution, and the spinning solution is prepared into regenerated silk by wet spinning.

[0010] Further, in step (A), the alkaline solution is an aqueous sodium hydroxide solution, and the pH value in the alkaline solution is 9 to 9.5.

[0011] Further, in step (A), the filtration includes: separating the protein from the impurities by using a 400-mesh filter screen to obtain a protein solution.

[0012] Further, in step (A), the protein content in the protein solution within the range of 7 to 8% includes:

[0013] The protein solution is added to dilute hydrochloric acid. The concentration of the dilute hydrochloric acid is 20%, and the pH value of the protein solution is 4.3 to 4.5 so that the protein in the protein solution is separated and precipitated from the water, thereby facilitating the control of the protein content in the protein solution.

[0014] Further, in step (B), the solvent is an aqueous solution of dimethylformamide or an aqueous solution of sodium thiocyanate, and the heating temperature is 40 to 50 °C.

[0015] Further, the concentration of the aqueous dimethylformamide solution is 10 to 15%, and the concentration of the aqueous sodium thiocyanate solution is 60 to 65%.

[0016] Further, in step (B), the concentration of the polyacrylonitrile solution is 15 to 16%.

[0017] Further, in step (C), the spinning solution includes one or a combination of an antibacterial aid, an anti-ultraviolet agent, a flame retardant, and a far-infrared aid.

[0018] Further, in step (C), the wet spinning includes:

[0019] The spinning solution is sprayed into a coagulation bath made of sodium thiocyanate through a spinneret to obtain raw filaments. After the raw filaments are drawn, heat-set, washed, crimped, and dried, regenerated silk is obtained.

[0020] Furthermore, the temperature of the heat setting is 150 to 180 °C.

[0021] Furthermore, the antibacterial aid includes nano-scale silver, copper, and zinc aids.

[0022] On the other hand, the present invention also provides silk produced by any of the above methods.

[0023] The present invention provides a method for producing silk. By using low-cost silkworm pupa protein or waste silk powder, through the process technology of reconnecting the silkworm pupa protein and silk protein therein into a new type of fiber, regenerated silk fibers suitable for textiles and non-woven products are produced, solving the contradiction between the supply and demand of silk, and reducing the price of silk products, making them consumer goods for ordinary people. Brief Description of the Drawings

[0024] The above content of the present invention and the following specific embodiments will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are only examples of the claimed technical solutions.

[0025] Figure 1 is a microscopic image of the linear structure of silk protein in the first embodiment of the present invention;

[0026] Figure 2 is a microscopic image of the globular structure of silk protein in the first comparative example of the present invention. Specific Embodiments

[0027] The following details the detailed features and advantages of the present invention in the specific embodiments. The content is sufficient for any person skilled in the art to understand the technical content of the present invention and implement it accordingly. And based on the description, claims and drawings disclosed in this specification, those skilled in the art can easily understand the related purposes and advantages of the present invention.

[0028] To make the purpose, technical solutions and advantages of the present invention clearer, the following will further describe the embodiments of the present invention in detail with reference to the accompanying drawings.

[0029] A method for making silk provided by the present invention includes the following steps:

[0030] (A) Preparation of Protein Solution

[0031] Dissolve and purify silkworm pupa powder or waste silk powder: Add dry silkworm pupa powder or waste silk powder to an aqueous solution of caustic soda (NaOH) with a concentration of 5-7%, at a temperature of 90-95°C for 4-5 hours, and always control the pH value between 9-9.5 to promote the dissolution of the protein in the silkworm pupa powder or waste silk powder into the caustic soda aqueous solution. After dissolution, use a separation filter to separate the protein from the impurities with a 400-mesh filter screen, filtering out the impurities and the protein of the silkworm pupa powder or waste silk powder that is not completely dissolved, thereby obtaining a protein solution. It should be noted that when dissolving the protein of the silkworm pupa powder or waste silk powder, the amount of caustic soda added is adjusted according to the pH value of the solution. When the pH value is low, increase the amount of caustic soda used; when the pH value is high, reduce the amount of caustic soda used. When the dissolved pH value > 10, the protein solution becomes clear and the protein precipitates, which is easily separated together with the impurities during filtration, making it difficult to control the protein content in the protein solution; when the pH value < 8, the protein dissolution rate is slow, increasing the production time cost.

[0032] Precipitation: Take 100 g of protein solution, add dilute hydrochloric acid (HCl) with a concentration of 20%, control the pH value at 4.3 - 4.5 to precipitate the protein in the protein solution, dry it, determine the proportion of the protein solution, and control the protein content at 7 - 8%. Since the concentration of the protein solution directly affects the protein content in the finished fiber, when the concentration is low, the protein content in the fiber is low. When the protein content is too high, intermolecular adhesion will affect the preparation of the spinning solution and the spinning. It should be noted that when the pH value is controlled at 4.3 - 4.5, the protein separates from the water and all the protein precipitates and solidifies, which is convenient for detecting the protein content in the protein solution. When the detected protein content is greater than or less than 7 - 8%, the protein is redissolved and the feeding ratio of silkworm chrysalis powder or waste silk powder is adjusted.

[0033] (B) Preparation of polyacrylonitrile solution

[0034] Add polyacrylonitrile material to an aqueous solution of dimethylformamide with a concentration of 12% or an aqueous solution of sodium thiocyanate with a concentration of 60 - 65%, and stir in an environment of 40 - 50 °C to completely dissolve the polyacrylonitrile material, and prepare a polyacrylonitrile mixed solution with a polyacrylonitrile concentration of 15 - 16%.

[0035] (C) Preparation of regenerated silk

[0036] Preparation of spinning solution: Mix the protein solution and the polyacrylonitrile solution in a ratio of 1 - 100:100 as needed, stir evenly to polymerize the protein and the polyacrylonitrile, and prepare a spinning solution. The ratio of the protein solution to the polyacrylonitrile solution is determined according to the protein content requirements in the finished fiber, and the ratio of the protein solution to the polyacrylonitrile solution does not exceed 3:2. When the ratio of the protein solution is too small, the protein content in the fiber decreases. When the ratio of the protein solution to the polyacrylonitrile solution exceeds 3:2, the single-fiber breaking strength of the fiber will decrease significantly. Add functional additives such as antibacterial additives (nano-scale silver, copper, zinc, etc.) and far-infrared additives (SiO2) with large market demand to the spinning solution.

[0037] Spinning: Use a pressure device to spray the spinning solution through a spinneret into a coagulation bath made of sodium thiocyanate to replace the water in the polymer and obtain the regenerated silk raw filament.

[0038] Drawing and setting: Draw the regenerated silk raw filament in the wet state through a drawing machine to reach the required fineness, and then perform heat setting at 150 - 180 °C to obtain regenerated silk.

[0039] Washing, curling, and drying. Use clear water to wash away the remaining auxiliaries on the regenerated silk filament bundle and the proteins that are not firmly bound to the outside of the fiber. When making staple fibers, cut them to the required length, put them into water at 98 - 100 °C, let the fibers freely contract and curl, send them into a dryer for drying, and finally package the finished product; when making filaments, directly dry them, let them fall on the spool, and perform filament splitting and winding.

[0040] Example 1

[0041] A method for making silk provided in this example includes the following steps:

[0042] (1) Dissolving and purifying silkworm pupa powder: Take 100 g of dry silkworm pupa powder and add it to 800 ml of a 5% caustic soda (NaOH) solution for dissolution. Use an electric heating furnace to heat to 90 °C, and use a pH meter to detect the whole process to control the pH value during the dissolution process between 9 and 9.5. After dissolving for four hours, filter and separate the solution with a 400 - mesh filter, dry and measure the filtered impurities, with a weight of 46 g, to obtain a protein solution with the protein content controlled between 7% and 8%. It should be noted that when the heating temperature for dissolving silkworm pupa powder reaches 90 - 95 °C, observe the dissolution process under a microscope, and the silk protein in the silkworm pupa powder becomes a linear structure. As Figure 1 shown, the linear structure makes the raw silkworm pupa powder dissolve more thoroughly, purify more silk protein, and make the connection between silk protein molecules and between silk protein molecules and polyacrylonitrile molecules more firm during the later production of the spinning solution.

[0043] (2) Making a polyacrylonitrile mixed solution: Take 125 g of polyacrylonitrile particles and add them to 800 ml of a 12% dimethylformamide aqueous solution, heat to 60 °C, and stir for 30 minutes to make a polyacrylonitrile solution.

[0044] (3) Making a spinning solution: Take 300 ml each of the protein solution and the polyacrylonitrile solution, add 2 g of nano - silver antibacterial powder, continue to heat to 90 °C, mix and stir for 30 minutes, mix evenly, and let it stand for 30 minutes. The protein and polypropylene are fully fused and grafted to obtain a spinning stock solution of silkworm pupa protein and polyacrylonitrile grafted.

[0045] (4) Spinning: Input the spinning solution into a spinning pump, and through a 0.08 - mm spinneret plate, spin it into a 15% sodium thiocyanate aqueous solution by weight to obtain the raw silk of regenerated silk, and the color of the obtained raw silk is milky white.

[0046] (5) After drawing, washing, and drying, obtain regenerated silk. Use a Kjeldahl apparatus to test the protein content, and measure that the silkworm protein content in the regenerated silk is 27%.

[0047] Comparative Example 1

[0048] The difference between this comparative example and Example 1 is that in step (1) for dissolving and purifying the silkworm pupa powder, the heating temperature during the dissolution of the silkworm pupa powder is below 80°C. Observing the dissolution process under a microscope, the silk protein in the silkworm pupa powder is in a spherical structure, as Figure 2 shown. The spherical structure results in poor dissolution effect of the raw silkworm pupa powder, and the bonding force between silk protein molecules and between silk protein molecules and polyacrylonitrile molecules is insufficient when preparing the spinning solution, resulting in very low strength between the obtained regenerated silk fibers.

[0049] Comparative Example 2

[0050] The difference between this comparative example and Example 1 is that in step (1) for dissolving and purifying the silkworm pupa powder, 150 g of silkworm pupa powder is added to 800 ml of a 5% sodium hydroxide (NaOH) solution for dissolution, and it is heated to 90°C using an electric heating furnace. At this time, the protein content in the silk protein solution in the dissolution solution is greater than 8%, and a pH meter is used to detect the whole process to control the pH value during the dissolution process between 9 and 9.5. After heating and dissolving for 1 hour, the solution becomes viscous and impurities such as silkworm pupa shells cannot be separated.

[0051] When the feeding ratio of the silkworm pupa powder is too high, and the protein content is greater than the range of 7 - 8%, the adhesion between protein molecules in the obtained protein solution is relatively serious, seriously affecting the uniformity of the mixing of the protein solution and the polyacrylonitrile solution in the step of preparing the spinning solution, further affecting the spinning effect, causing the spinneret to be blocked, and the defects of the regenerated silk fibers are serious.

[0052] To further illustrate the advantages of the present invention, the beneficial effects will be demonstrated through the following detection methods.

[0053] I. Detection and comparison of mulberry silk and the silkworm pupa powder raw material used in the present invention by high performance liquid chromatography

[0054] 1. Instruments and reagents

[0055] The high performance liquid chromatograph is of the Agilent1100 model (product of Agilent Technologies, Inc., USA).

[0056] 18 kinds of amino acid standards are purchased from Afa Aesar Company. O-phthalaldehyde, sodium acetate, triethylamine, etc. are domestic analytical pure solutions, purchased from Shanghai Guoyao Reagent Co., Ltd.; methanol, acetonitrile and tetrahydrofuran are chromatographic pure reagents, purchased from Tianjin Siyou Chromatographic Reagent Products.

[0057] 2 Detection methods

[0058] Mobile phase A uses 20 mmol / L sodium acetate buffer solution: the sodium acetate buffer solution contains 0.5% tetrahydrofuran and 0.3% triethylamine, pH = 10.3, and is filtered with a 0.45 filter membrane;

[0059] Mobile phase B uses chromatographically pure methanol reagent; Mobile phase C: chromatographically pure acetonitrile reagent.

[0060] Weigh appropriate amounts of natural mulberry silk and the silkworm pupa powder raw material used in the present invention (both containing approximately 50 mg of protein), place them in ampoules respectively, add 5 ml of 6 mol / L HCl, evacuate and seal, hydrolyze at 110°C for 24 h, remove acid in a vacuum desiccator after opening, make up the volume to 25 ml, store frozen, and detect by injection after derivatization treatment.

[0061] Chromatographic analysis conditions: The chromatographic column is an Agilent Eclipse AAA amino acid analysis column (4.6 mm * 150 mm, 5 μm), a DAD diode array detector, the detection wavelength is 338 nm from 1 to 32 min, and 262 nm after 32 min, the column temperature is 35°C, and gradient elution is carried out according to the conditions in Table 1.

[0062] Table 1 Mobile phase gradient elution program

[0063] Time t / min Mobile phase A(%) Mobile phase B(%) Mobile phase C(%) <![CDATA[Flow rate / ml min ～1 > 0.0 100 0.0 0.0 0.6 4.0 98.0 1.0 1.0 0.6 10.0 92.0 4.0 4.0 0.8 35.0 55.0 25.0 20.0 1.0 40.0 55.0 25.0 20.0 1.0

[0064] The test results of mulberry silk and silkworm pupa powder raw materials are shown in Table 2:

[0065] Table 2: Comparison of the amino acid content of mulberry silk protein and silkworm pupa protein

[0066]

[0067]

[0068] Among them: ☆ represents essential for humans.

[0069] The two main components in natural mulberry silk are silk fibroin and sericin proteins. And silkworm pupa protein, as the remaining protein after the silkworm spins silk, as can be seen from Table 2, the 18 amino acids in silkworm pupa protein are exactly the same as the silk protein in mulberry silk. Moreover, due to the lower price of silkworm pupa protein, the present invention innovatively uses regenerated silk made from silkworm pupa protein, making the price of the regenerated silk fully adaptable to the consumption of the general public. And the regenerated silk obtained by using silkworm pupa protein in Example 1 of the present invention has properties similar to those of natural mulberry silk, with high strength and excellent elasticity, especially in terms of good moisture absorption, soft handfeel, gorgeous appearance and elegant luster.

[0070] II. Comparison of dyeing ability

[0071] The regenerated silk obtained in Example 1, the mulberry silk produced in Tongxiang, Zhejiang, and the Xinjiang cotton of the 229th batch auctioned by the national reserve network are respectively subjected to the following dyeing processes:

[0072] Cationic Dyeing: Take 10 grams each of the regenerated silk obtained in Example 1, mulberry silk produced in Tongxiang, Zhejiang, and Xinjiang cotton, and place them separately into 300-ml dyeing cups. First, add 1.2 grams of hydrogen peroxide (H2O2) to the dyeing cup with Xinjiang cotton. In a constant-temperature dyeing agent, set the temperature at 100 °C and perform oxygen bleaching for 30 minutes. After deoxygenation with a 10% acetic acid solution and washing with clear water, put it back into the dyeing cup. Inject 250 grams of pure water into the three dyeing cups respectively, add 10 ml of cationic dye solution and auxiliary agents, and place them in a constant-temperature dyeing machine. The cationic dye (orange) is configured as follows: cationic light yellow GL 1.1%, cationic red GRL 0.9%, cationic blue BL 0.06%; the auxiliary agents are configured as follows: leveling agent 1%, acetic acid 3%. The initial temperature is room temperature, preferably 25 °C. Let the dye liquor run for 3 passes, then start heating. The first heating stage is preferably at a rate of 1 °C per minute until it reaches 85 °C, then keep it warm for 30 minutes. In the second heating stage, raise the temperature to 100 °C at a rate of 3 °C per minute and keep it warm for 30 minutes. Then lower the temperature below 40 °C, drain the residual liquid, and wash it 3 times with clear water at 25 °C to wash off the floating color; spin-dry and dry the dyed materials to obtain the dyed regenerated silk, mulberry silk, and Xinjiang cotton respectively.

[0073] Reactive Dyeing: Take 10 grams each of the regenerated silk obtained in Example 1, mulberry silk produced in Tongxiang, Zhejiang, and Xinjiang cotton, and place them separately into 300-ml dyeing cups. First, add 1.2 grams of hydrogen peroxide (H2O2) to the dyeing cup with Xinjiang cotton. In a constant-temperature dyeing agent, set the temperature at 100 °C and perform oxygen bleaching for 30 minutes. After deoxygenation with a 10% acetic acid solution and washing with clear water, put it back into the dyeing cup. Inject 200 grams of pure water into the three dyeing cups respectively. Add 10 ml of reactive dye solution and auxiliary agents, and place them in a constant-temperature dyeing machine. The reactive dye solution (China red) is configured as follows: red S-2B 4.4%, red 3BSN 2.9%, orange ED-2R 4%; the auxiliary agent is configured as follows: sodium sulfate 50 g / L. After standing for 20 minutes, raise the temperature to 60 °C at a rate of 1 °C per minute, keep it warm for 30 minutes, then add 20 ml of a 5 g / L solution of soda ash, raise the temperature to 90 °C, keep it warm for 30 minutes, lower the temperature to 40 degrees Celsius, wash it three times with clear water, and then dry it to obtain the dyed regenerated silk, mulberry silk, and Xinjiang cotton respectively.

[0074] Acid Dyeing: Take 10 grams each of the regenerated silk obtained in Example 1, mulberry silk produced in Tongxiang, Zhejiang, and Xinjiang cotton, and place them separately into 300 ml dyeing cups. First, add 1.2 grams of hydrogen peroxide (H2O2) to the Xinjiang cotton dyeing cup. In a constant-temperature dyeing agent, set the temperature at 100 °C and perform oxygen bleaching for 30 minutes. After deoxidizing with a 10% acetic acid solution and washing with clear water, put it back into the dyeing cup. Pour 200 grams of pure water into each of the three dyeing cups. Add 10 ml of weak acid dye solution and auxiliaries, and place them in a constant-temperature dyeing machine. The weak acid dye (orange-red) solution is prepared as follows: 1.8% of weak acid brilliant orange 2R and 0.15% of weak acid pink BR; the auxiliaries are prepared as follows: 0.3 g / L of peregal O and 0.5 g / L of salt. After heating to 50 °C, continue to heat at a rate of 0.7 °C per minute to 95 °C, keep warm for 30 minutes, cool down, and wash with clear water. Put them back into the dyeing cups again, add 200 ml of clear water respectively, add 6 g of environmental protection fixing agent ZS-201 and 0.2 ml of 30% glacial acetic acid, heat to 50 °C, keep warm for 20 minutes to complete color fixation, then wash with water and dry to obtain dyed regenerated silk, mulberry silk, and Xinjiang cotton respectively.

[0075] The evaluation of the dyeing ability test results is carried out by the dye uptake rate and color fixation rate, and the results are shown in Table 3 as follows:

[0076] Table 3: Dyeing ability table of regenerated silk, mulberry silk, and Xinjiang cotton

[0077] Cationic dye Reactive dye Acid dye Regenerated silk Dyeing performance Excellent Excellent Excellent Mulberry silk Dyeing performance Poor Good Excellent Xinjiang cotton Dyeing performance Poor Excellent Good

[0078] As can be seen from Table 3, when using cationic dyes for dyeing, the regenerated silk obtained in Example 1 colors relatively quickly, has a high dye uptake rate, and the color is bright.

[0079] The regenerated silk obtained in Example 1 also overcomes the defects of mulberry silk in dyeing. When using reactive dyes for dyeing, the protein colors relatively quickly and has a high coloring rate. The regenerated silk obtained in Example 1 achieves synchronous coloring with cotton products.

[0080] In the acid dye process, the coloring effect of the regenerated silk obtained in Example 1 is similar to that of mulberry silk. Therefore, as described above, the regenerated silk obtained in Example 1 can adapt to the coloring of various dye processes, meet diversified usage requirements, and meet more production and usage requirements while reducing production costs.

[0081] III. Antibacterial Effect

[0082] In the regenerated silk obtained by adding nano-silver antibacterial agent to the spinning solution prepared in Example 1, the bacteriostatic rates of the raw silk of the regenerated silk and after 20 washes are detected, and the results are shown in Table 4 as follows:

[0083] Table 4: Detection results of antibacterial and bacteriostatic rates of regenerated silk are as follows

[0084]

[0085] In the regenerated silk fibers obtained in Example 1, functional additives can be added as required, including additives such as antibacterial, anti-mite, and far-infrared additives that are relatively recognized in the market, and the additives added to the spinning solution have a durable property and will not disappear after multiple washes.

[0086] IV. Wash resistance

[0087] Wash resistance: The regenerated silk obtained in Example 1 was tested using the AATCC 61-2A standard.

[0088] The regenerated silk obtained in Example 1 overcomes the defects in the washing and care of mulberry silk, can be washed by water, hand, and machine, and is not easy to pill.

[0089] The terms and expressions used herein are for descriptive purposes only, and the present invention should not be limited to these terms and expressions. The use of these terms and expressions does not mean excluding any equivalent features of the illustration and description (or parts thereof), and it should be recognized that various modifications that may exist should also be included within the scope of the claims. Other modifications, variations, and substitutions may also exist. Accordingly, the claims should be regarded as covering all such equivalents.

[0090] Similarly, it should be noted that although the present invention has been described with reference to the current specific embodiments, those of ordinary skill in the art in this technical field should recognize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions can be made without departing from the spirit of the present invention. Therefore, as long as the changes and variations of the above embodiments are within the scope of the spirit of the present invention, they will fall within the scope of the claims of the present invention.

Claims

1. A method for making silk, characterized in that, It includes the following steps: (A) Preparation of protein solution: Add silkworm pupa powder or waste silk powder into an alkaline solution, heat at a temperature of 90 - 95 °C for 4 - 5 hours, and filter to obtain a protein solution. Among them, the protein content in the protein solution is in the range of 7 - 8%; (B) Preparation of polyacrylonitrile solution: Add polyacrylonitrile into a solvent and heat to dissolve it to obtain a polyacrylonitrile solution; (C) Preparation of regenerated silk: Mix the protein solution obtained in step (A) and the polyacrylonitrile solution obtained in step (B) in a ratio of 1 - 100:100, and stir evenly to form a spinning solution. The spinning solution is prepared into regenerated silk by wet spinning.

2. The method for making silk according to claim 1, wherein In step (A), the alkaline solution is an aqueous sodium hydroxide solution, and the pH value of the alkaline solution is 9 - 9.

5.

3. The production method of silk according to claim 2, characterized in that, In step (A), the filtration includes: separating the protein from impurities using a 400 - mesh filter screen to obtain the protein solution.

4. The method for making silk according to claim 2, wherein, In step (A), the protein content in the protein solution being in the range of 7 - 8% includes: Adding the protein solution into dilute hydrochloric acid with a concentration of 20%, and the pH value of the protein solution is 4.3 - 4.5 so that the protein in the protein solution separates and precipitates from water, thereby facilitating the control of the protein content in the protein solution.

5. The method for making silk according to claim 1, characterized in that, In step (B), the solvent is an aqueous dimethylformamide solution or an aqueous sodium thiocyanate solution, and the heating temperature is 40 - 50 °C.

6. The method for making silk according to claim 5, wherein The concentration of the aqueous dimethylformamide solution is 10 - 15%, and the concentration of the aqueous sodium thiocyanate solution is 60 - 65%.

7. The production method of silk according to claim 5, characterized in that, In step (B), the concentration of the polyacrylonitrile solution is 15 - 16%.

8. The method for making silk according to claim 1, characterized in that, In step (C), the spinning solution includes one or a combination of antibacterial agents, ultraviolet - resistant agents, flame retardants, and far - infrared agents.

9. The method for making silk according to claim 1, wherein In step (C), the wet spinning includes: The spinning solution is sprayed into a coagulation bath made of sodium thiocyanate through a spinneret to obtain raw silk, and the raw silk is obtained as regenerated silk after drawing, heat setting, washing, crimping, and drying.

10. Silk produced by the method according to any one of claims 1 - 9.

Images