CN107988783B - Modified flexible material for silk non-woven fabric and preparation method thereof - Google Patents

Abstract

The invention discloses a modified flexible material for silk non-woven fabric and a preparation method thereof, and belongs to the technical field of non-woven fabric materials. In the invention, pure natural mulberry silk is used, water bath treatment is carried out through calcium chloride and acetic acid solutions of different concentrations, washed, and then quickly dried to rapidly change the internal stress of the silk to prepare modified silk with a certain degree of curvature. Compared with the original silk fiber, the modified silk material obtained after this treatment has greatly improved its own bending degree, and the strength is not significantly reduced, which can solve other problems through coating, blending, sericin bonding and other methods. Improve the strength of the fabric, resulting in the shortcomings of breathability and moisture permeability and poor softness of the fabric. This modified silk material has excellent performance, is mild and non-irritating, and does not introduce other substances, which can give full play to the good performance of silk fibroin. Improve the friction force per unit area, thereby improving the shortcomings of insufficient strength of pure silk non-woven products.

Description

A kind of modified flexible material for silk non-woven fabric and preparation method thereof

technical field

The invention relates to a modified flexible material of silk non-woven fabric and a preparation method thereof, belonging to the technical field of non-woven fabric materials.

Background technique

Silk is a natural protein fiber. It contains 18 amino acids that are beneficial to the human body. The protein content is more than 97%. Silk fibroin is the main body. Silk fibroin is non-toxic and harmless, safe and reliable, has excellent biocompatibility, and is suitable for development and modification into new materials. Among them, serine and threonine can delay aging, and leucine can accelerate cell metabolism. These advantages of silk have led researchers to deepen the study of its modified materials, such as: impregnation, coating, grafting, blending, etc., to endow silk with different properties.

At present, when silk is used as a raw material for processing spunlace pure silk non-woven fabrics, it is easy to cause shortcomings such as insufficient fabric strength and easy tearing of fabrics. Therefore, researchers have modified the fabric. The current methods are: (1) Improve the strength of the fabric by coating and dipping the strength agent, but this easily leads to a decrease in the breathability and moisture permeability of the fabric; (2) By melting The method of dissolving sericin on the surface of undegummed silk, and then drying it, uses sericin to bond the silk to each other to improve the strength of the fabric, but the hardness of the fabric obtained by this method is too high and the softness is very poor; (3) Through saturation The method of preparing curved silk with calcium salt increases the degree of curvature of the silk and increases the friction between the silks, but the silk after this treatment has insufficient degree of curvature, and the strength drops a lot, which limits the strength of the fabric. (4) Non-woven fabrics are prepared by blending fibers such as polyester and tencel with silk. Although the strength of the fabric is improved, its practical value will be greatly reduced.

Before the present invention was made, in the Chinese invention patent (CN100379915) "Silk Modified Nonwoven Fabric Containing Sericin and Its Use", glutaraldehyde solution was used to fix sericin on silk fibers, and at the same time, surfactant was added to make it soft , Although it can improve the strength of silk non-woven fabrics, during the drying and cooling process, the melting and coagulation of sericin will lead to poor hand feel of the fabric, the added surfactant may dissolve out and stimulate the skin, and the added glutaraldehyde Toxic, irritating, and causing a decrease in biocompatibility. The Chinese invention patent with publication number CN105671790A provides a silk hot air non-woven fabric, which uses the fusion bonding effect of ES fibers with a melting point of 130 ° C to bond the silk non-woven fabric with each other to increase the strength. , but high temperature will destroy the silk fiber, and the addition of chemical fiber ES fiber may reduce the skin-friendly and biocompatibility of pure silk.

SUMMARY OF THE INVENTION

Aiming at the deficiencies of the existing silk non-woven fabrics, the present invention provides a modified flexible silk non-woven fabric that can fully maintain the biocompatibility and strength of the silk fibroin material and has high flexibility. Materials and methods for their preparation.

The technical scheme for realizing the object of the present invention is to provide a method for preparing a modified flexural material for silk non-woven fabrics, which takes Bombyx mori silk as a raw material, undergoes degumming, washing and drying successively, and then carries out the processing of the following steps:

(1) Soak the degummed and dried Bombyx mori silk in a mixed solution of calcium chloride and acetic acid containing a silk protective agent, and treat it for 10 min to 60 min at a temperature of 60°C to 90°C. After the silk absorbs the solution, swollen silk is obtained. The silk protecting agent is a compound comprising sodium sulfate, glycerin, saccharin and sucrose, and the dosage of the silk protecting agent is 1% to 3% of the silk quality; the calcium chloride solution is 6 to 8 mol/L, and the acetic acid The solution is 0.04～0.7 mol/L;

(2) Roll the swollen silk through a pressure roller to remove excess swelling liquid, and the pressure of the pressure roller is 0.1 MPa to 0.4 MPa;

(3) Wash the silk treated in step (2) immediately with water until the pH value of the eluate is greater than 6;

(4) drying the washed silk in an oven at a temperature of 100° C. to 110° C. to a constant weight to obtain a modified flexible material for silk non-woven fabrics.

The silk protecting agent of the present invention comprises, by mass, 30%-60% sodium sulfate, 20%-50% sucrose, 5%-10% glycerin, and 0.1%-5% saccharin.

The technical scheme of the present invention also includes a modified flexible material for silk non-woven fabric obtained by the above preparation method.

The bending degree of the silk fiber of the modified flexible material for silk nonwoven fabric is 10-30%, and the single-filament strength is 5-6 cN.

The principle of the present invention is as follows: the silk has a certain characteristic of absorbing acid, so that it is immersed in dilute acetic acid. After absorbing the dilute acetic acid, partial swelling occurs. In order to improve the degree of swelling, calcium chloride is also added to promote acetic acid molecules. Entering the inside of the silk, the silk is further swelled, and under the protection of the silk protective agent, only the swelling of the silk is controlled and the degradation of the fibroin is minimized. The swollen silk is washed with water to remove acetic acid, calcium chloride and silk protectant, and then quickly dried. Due to the uneven expansion stress of swelling and the stress of drying shrinkage, the silk is bent and wound, forming a silk material with a certain twist. The invention adopts the method of improving the curvature of silk to prepare the modified silk modified material, starts from the product raw material for modification, improves the bending degree of the silk, and then increases the entanglement performance between the silks in the product, and is suitable for producing pure silk without The raw material of spinning cloth can be used in biological dressings, silk facial masks, silk sanitary napkins and other products.

Compared with the existing pure silk non-woven raw materials, the advantages of the present invention are:

(1) The present invention can greatly improve the bending degree of the silk through the calcium chloride/acetic acid solution treatment on the silk, and the bending degree can be increased to 10-30%, and the strength of the silk itself will not be damaged.

(2) Starting from the modification of the raw material of the silk non-woven fabric itself, it can solve other methods such as coating, blending, sericin bonding, etc., only considering the improvement of the strength to cause the air and moisture permeability, softness, and affinity of the silk non-woven fabric. The disadvantage of skin loss.

(3) The modified material of silk non-woven fabric prepared by the present invention is non-toxic and harmless, without the introduction of any substance, while solving the lack of strength of pure silk non-woven fabric and improving the tearing performance of the non-woven fabric, it can Fully maintain the biocompatibility of silk fibroin materials.

Description of drawings

Fig. 1 is the silk morphology photograph of untreated sample;

Fig. 2 is the silk morphological photograph of embodiment one sample;

Fig. 3 is the silk morphological photograph of embodiment two samples;

Fig. 4 is the silk morphological photograph of embodiment three samples;

Fig. 5 is the silk morphological photograph of embodiment four samples;

6 is a comparison diagram of the bending degree detection results of samples provided by various embodiments of the present invention and untreated silk;

FIG. 7 is a comparison diagram of the strength detection results of the samples provided by various embodiments of the present invention and untreated silk.

Detailed ways

The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

Example 1:

1. Get 1 kilogram of degummed and dried Bombyx mori silk, soak it in 5000 milliliters of 0.04 mol/L dilute acetic acid, 6.7 mol/L calcium chloride solution containing 20 grams of silk protective agent for 50 min, at a temperature of 60 ° C, absorb the acid solution to obtain Swelled silk; wherein the silk protecting agent is sodium sulfate containing 58% by mass, sucrose by mass 35%, glycerin by mass 6%, and saccharin by mass 1%.

2. Pass the swollen silk through a pressing roller to remove excess acid, and the pressure of the pressing roller is 0.2 MPa;

3. Take out the dried silk and wash thoroughly with water until the pH value in the washing liquid rises to 6.5;

4. Put the cleaned silk in an oven at 100°C and quickly dry to constant weight to obtain silk with a certain degree of curvature, which can be used for the manufacture of silk non-woven fabrics.

See Figure 1 and Figure 2 for the silk morphology before and after treatment.

Detection of bending degree: Put the treated silk on the black velvet plate, fix one end, hang the silk, and measure the length after treatment. Then apply a certain stress to the other end of the silk to straighten it to measure its original length, and calculate the curvature = (original length - treated length) / original length * 100%. Through detection, the bending degree of the silk material obtained in this example is 14%, see FIG. 6 . See Figure 7 for the strength test results of the monofilament.

Embodiment 2:

1. Get 2 kilograms of degummed and dried Bombyx mori silk, soak in 10 liters of 0.21 mol/L dilute acetic acid, 7.0 mol/L calcium chloride solution containing 40 grams of silk protective agent for 30 min, temperature 70 ℃, absorb acid solution to obtain Swelled silk; wherein the silk protective agent is sodium sulfate containing 45% by mass, sucrose containing 45% by mass, glycerol containing 8% by mass, and saccharin containing 2% by mass.

2. Pass the swollen silk through a pressing roller to remove excess acid, and the pressure of the pressing roller is 0.25 MPa;

3. Take out the dried silk and wash thoroughly with water until the pH value in the washing liquid rises to 6.2;

4. Put the cleaned silk into a 101°C oven to dry quickly to constant weight to obtain silk with a certain degree of curvature, which can be used for the manufacture of silk non-woven fabrics.

See Figure 1 and Figure 3 for the silk morphology before and after treatment.

Detection of bending degree: Put the treated silk on the black velvet plate, fix one end, hang the silk, and measure the length after treatment. Then apply a certain stress to the other end of the silk to straighten it to measure its original length, and calculate the curvature = (original length - treated length) / original length * 100%. Through detection, the bending degree of the silk material obtained in this example is 18%, see FIG. 6 . See Figure 7 for the strength test results of the monofilament.

Embodiment three:

1. Get 2 kilograms of degummed and dried Bombyx mori silk, soak in 10 liters of 0.42 mol/L dilute acetic acid, 7.2 mol/L calcium chloride solution containing 40 grams of silk protective agent for 40 min, temperature 65 ℃, absorb acid solution to obtain Swelled silk; wherein the silk protecting agent is sodium sulfate containing 42% by mass, sucrose by mass 50%, glycerin by mass 7%, and saccharin by mass 1%.

2. Pass the swollen silk through a pressing roller to remove excess acid, and the pressure of the pressing roller is 0.25 MPa;

3. Take out the dried silk and wash thoroughly with water until the pH value in the eluate rises to 6.1;

4. Put the cleaned silk into a 101°C oven to dry quickly to constant weight to obtain silk with a certain degree of curvature, which can be used for the manufacture of silk non-woven fabrics.

See Figure 1 and Figure 4 for the silk morphology before and after treatment.

Detection of bending degree: Put the treated silk on the black velvet plate, fix one end, hang the silk, and measure the length after treatment. Then apply a certain stress to the other end of the silk to straighten it to measure its original length, and calculate the curvature = (original length - treated length) / original length * 100%. Through detection, the bending degree of the silk material obtained in this example is 20%, see FIG. 6 . See Figure 7 for the strength test results of the monofilament.

Embodiment 4:

1. Get 2 kilograms of degummed and dried Bombyx mori silk, soak in 10 liters of 0.62 mol/L dilute acetic acid, 7.4 mol/L calcium chloride solution containing 40 grams of silk protective agent for 35 min, temperature 76 ℃, absorb acid solution to obtain Swelled silk; wherein the silk protecting agent is sodium sulfate containing 40% by mass, sucrose by mass 51%, glycerin by mass 8.1%, and saccharin by mass 0.9%.

2. Pass the swollen silk through a pressing roller to remove excess acid, and the pressure of the pressing roller is 0.25 MPa;

3. Take out the dried silk and wash thoroughly with water until the pH value in the eluate rises to 6.4;

4. Put the cleaned silk into a 101°C oven to dry quickly to constant weight to obtain silk with a certain degree of curvature, which can be used for the manufacture of silk non-woven fabrics.

See Figure 1 and Figure 5 for the silk morphology before and after treatment.

Detection of bending degree: Put the treated silk on the black velvet plate, fix one end, hang the silk, and measure the length after treatment. Then apply a certain stress to the other end of the silk to straighten it to measure its original length, and calculate the curvature = (original length - treated length) / original length * 100%. Through testing, the bending degree of the silk material obtained in this example is 26%, see FIG. 6 . See Figure 7 for the strength test results of the monofilament.

Referring to Figures 1 to 5, it is a comparison photo of the silk morphology before and after treatment in each embodiment of the present invention; wherein, A is an untreated sample, B is a sample of the first embodiment, C is the sample of the second embodiment, and D is an embodiment The three samples, E is the fourth sample of the embodiment, it can be seen from the figure that the bending degree of the silk is greatly improved after the treatment.

Referring to FIG. 6 , it is a comparison diagram of the bending degree detection results of the samples provided by the various embodiments of the present invention and the untreated silk. It can be seen from Figure 6 that the curvature of the untreated silk is only about 5%, and the curvature of the treated silk is greatly improved.

Referring to FIG. 7 , it is a comparison diagram of the strength detection results of the samples provided by the various embodiments of the present invention and untreated silk. It can be seen from Figure 7 that the strength of the silk does not decrease significantly after the treatment.

Claims (4)

1. a kind of preparation method of silk non-woven fabric with modified flexure material, with silkworm silk as raw material, after degumming, washing, drying process successively, it is characterized in that carrying out the processing of following steps again: (1) Soak the degummed and dried Bombyx mori silk in a mixed solution of calcium chloride and acetic acid containing a silk protective agent, and treat it for 10 min to 60 min at a temperature of 60°C to 90°C. After the silk absorbs the solution, swollen silk is obtained. The silk protecting agent is a compound comprising sodium sulfate, glycerin, saccharin and sucrose, and the dosage of the silk protecting agent is 1% to 3% of the silk quality; the calcium chloride solution is 6 to 8 mol/L, and the acetic acid The solution is 0.04～0.7 mol/L; (2) Roll the swollen silk through a pressure roller to remove excess swelling liquid, and the pressure of the pressure roller is 0.1 MPa to 0.4 MPa; (3) Wash the silk treated in step (2) immediately with water until the pH value of the eluate is greater than 6; (4) drying the washed silk in an oven at a temperature of 100° C. to 110° C. to a constant weight to obtain a modified flexible material for silk non-woven fabrics. 2. The preparation method of a modified flexible material for silk nonwoven fabric according to claim 1, wherein: in the silk protective agent, by mass, it comprises 30%～60% of sodium sulfate, 20% to 50% sucrose, 5% to 10% glycerol, 0.1% to 5% saccharin. 3. a kind of modified flex material for silk non-woven fabric obtained by the preparation method of claim 1. 4 . The modified flexible material for silk non-woven fabric according to claim 3 , wherein the bending degree of the silk fibers is 10-30%, and the monofilament strength is 5-6 cN. 5 .

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