Multifunctional villus based on modified chitosan grafted cashmere and preparation method of multifunctional villus

Abstract

The invention relates to the field of villus, in particular to multifunctional villus based on modified chitosan grafted cashmere and a preparation method of the multifunctional villus, and aims to solve the problems that existing villus is poor in antibacterial performance, the purpose of long-acting bacteriostasis is difficult to achieve, and high-end application of the villus is limited. According to the preparation method, firstly, cashmere is treated, so that the cashmere is convenient to graft and modify, then, modified chitosan is prepared, finally, the primarily treated cashmere is modified by utilizing the modified chitosan, and grafted chitosan chains can remarkably improve the antibacterial performance of cashmere fibers; meanwhile, quaternary ammonium salt groups can be fixed to cashmere in a chemical bond mode, bacterial cell membranes of bacteria making contact with the quaternary ammonium salt groups are durably destroyed through the quaternary ammonium salt groups, the efficient sterilization effect is provided, loss is not likely to happen, safety is high, and the long-acting antibacterial effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of cashmere, specifically to multifunctional cashmere based on modified chitosan grafted cashmere and its preparation method. Background Technology

[0002] As a natural fiber, cashmere is widely used in textiles due to its softness and warmth. Cashmere, with its excellent warmth, lightness, and breathability, is considered one of the most precious natural fibers. However, cashmere fibers are rich in protein and moisture, making them a breeding ground for bacteria, leading to mold and unpleasant odors, especially in humid environments or after prolonged wear, highlighting the urgent need for antibacterial properties.

[0003] To improve cashmere properties, existing technologies mainly employ padding and impregnation methods to load antibacterial agents (such as silver ions and quaternary ammonium salts) onto the cashmere surface. However, these methods suffer from limited functionality, poor washability, and easy removal of the antibacterial agents after washing, resulting in a significant decrease in antibacterial performance and limiting their high-end applications.

[0004] Therefore, developing a multifunctional cashmere based on modified chitosan grafted cashmere and its preparation method is of great practical significance. Summary of the Invention

[0005] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide a multifunctional cashmere based on modified chitosan grafted cashmere and its preparation method, which solves the problem that the existing cashmere has poor antibacterial performance, is difficult to achieve long-term antibacterial effect, and limits its high-end application.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] In a first aspect, this application provides a method for preparing multifunctional cashmere based on modified chitosan grafted cashmere, comprising the following steps:

[0008] Pre-treated cashmere, modified chitosan, dibutyltin dilaurate, and acetic acid solution were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred for 10-15 minutes at a temperature of 25-30℃ and a stirring rate of 200-300 r / min. The temperature was then raised to 50-60℃ and the stirring was continued for 2-3 hours. The temperature was then raised to 80-90℃ and the stirring was continued for 30-50 minutes. After the reaction was completed, the reaction product was cooled to room temperature and then vacuum filtered. The filter cake was washed 3-5 times with distilled water and then placed in a vacuum drying oven and dried at a temperature of 50-60℃ for 3-5 hours to obtain multifunctional cashmere based on modified chitosan grafted with cashmere.

[0009] In a preferred embodiment of the present invention, the ratio of the amount of the pre-treated cashmere, modified chitosan, dibutyltin dilaurate, and acetic acid solution is 5g:1.6-3.8g:0.1-0.2g:90-100mL; and the mass fraction of the acetic acid solution is 2-3%.

[0010] In a preferred embodiment of the present invention, the pre-treated cashmere is prepared by the following steps:

[0011] Step a1: Add cashmere and cashmere treatment solution to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection. Stir and react for 3-5 minutes at a temperature of 25-30℃ and a stirring rate of 200-300 r / min. Then raise the temperature to 40-45℃ and continue stirring for 40-60 minutes. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake 3-5 times with distilled water and then place it in a vacuum drying oven and dry it for 1-3 hours at a temperature of 50-60℃ to obtain pretreated cashmere.

[0012] Step a2: Add the pretreated cashmere and protease solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir the reaction at 25-30℃ and 200-300 r / min for 10-15 min. Then raise the temperature to 50-55℃ and continue stirring for 1-1.5 h. After the reaction is complete, filter the reaction product while it is still hot. Soak the filter cake in distilled water at 90-95℃ for 15-20 min, then vacuum filter it. Place the filter cake in a vacuum drying oven and dry it at 50-60℃ for 2-4 h to obtain the pretreated cashmere.

[0013] In a preferred embodiment of the present invention, the ratio of cashmere to cashmere treatment solution in step a1 is 2g:20-25mL.

[0014] In a preferred embodiment of the present invention, the cashmere treatment solution in step a1 is a mixture of hydrogen peroxide, sodium silicate and deionized water in a ratio of 1-5 mL: 0.5-0.9 g: 90-100 mL; the mass fraction of the hydrogen peroxide is 30-35%.

[0015] In a preferred embodiment of the present invention, the ratio of the amount of pretreated cashmere to protease solution in step a2 is 2g:20-25mL.

[0016] In a preferred embodiment of the present invention, the mass fraction of the protease solution in step a2 is 2-3%; the protease is SAVINASE 8.0T.

[0017] In a preferred embodiment of the present invention, the modified chitosan is prepared by the following steps:

[0018] Step b1: Add formic acid and deionized water to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir for 10-15 minutes at a temperature of 25-30℃ and a stirring rate of 200-300 r / min. Then add chitosan and continue stirring for 20-25 minutes. Next, add formaldehyde solution and heat to 70-75℃ and continue stirring for 20-40 hours. After the reaction is complete, cool the reaction product to room temperature and adjust the pH to 9-10 with sodium hydroxide solution. Then, vacuum filter the product and wash the filter cake 3-5 times with distilled water. Then, place it in a vacuum drying oven and dry it at a temperature of 40-50℃ for 3-5 hours to obtain dimethylaminochitosan.

[0019] Step b2: Dimethylaminochitosan, epichlorohydrin, and N-methyl-2-pyrrolidone were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred for 10-15 minutes at a temperature of 25-30℃ and a stirring rate of 200-300 r / min. Then, the temperature was raised to 60-65℃ and the mixture was stirred for 3-5 hours. Sodium hydroxide solution was then added and the mixture was stirred for 2-3 hours. After the reaction was completed, the reaction product was cooled to room temperature and then poured into a mixed solution. The mixture was then vacuum filtered, and the filter cake was placed in a vacuum drying oven and dried for 2-3 hours at a temperature of 40-50℃ to obtain epoxy-quaternized chitosan.

[0020] Step b3: Add epoxy-quaternized chitosan, isophorone diisocyanate, dibutyltin dilaurate, 1,4-dioxane, and toluene to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 25-30℃ and 200-300 r / min for 10-15 min. Then raise the temperature to 70-75℃ and continue stirring for 2-3 h. After the reaction is complete, cool the reaction product to room temperature, then remove the solvent by rotary evaporation. Wash with diethyl ether and distilled water 3-5 times in sequence, then place in a vacuum drying oven and dry at 40-50℃ for 3-5 h to obtain modified chitosan.

[0021] In a preferred embodiment of the present invention, the ratio of formic acid, deionized water, chitosan and formaldehyde solution in step b1 is 15-20 mL: 40-50 mL: 3 g: 25-30 mL.

[0022] In a preferred embodiment of the present invention, the degree of deacetylation of the chitosan in step b1 is 90% and the average molecular weight is 10 kDa; the mass fraction of the formaldehyde solution is 35-37%; and the mass fraction of the sodium hydroxide solution is 35-40%.

[0023] In a preferred embodiment of the present invention, the ratio of dimethylaminochitosan, epichlorohydrin, N-methyl-2-pyrrolidone and sodium hydroxide solution in step b2 is 3g:10-15g:20-30mL:20-30mL.

[0024] In a preferred embodiment of the present invention, the sodium hydroxide solution in step b2 has a mass fraction of 20-25%; the mixed solution is prepared by mixing ethanol and diethyl ether in equal volumes.

[0025] In a preferred embodiment of the present invention, the ratio of epoxy quaternized chitosan, isophorone diisocyanate, dibutyltin dilaurate, 1,4-dioxane and toluene in step b3 is 5g:1.2-1.8g:0.02-0.04g:20-25mL:8-10mL.

[0026] Secondly, this application provides a multifunctional cashmere based on modified chitosan grafted cashmere, which is prepared using the preparation method of multifunctional cashmere based on modified chitosan grafted cashmere as described in the first aspect.

[0027] The beneficial effects of this invention are:

[0028] This invention relates to a multifunctional cashmere-based product based on modified chitosan grafted cashmere and its preparation method. The method involves stirring and reacting pre-treated cashmere, modified chitosan, dibutyltin dilaurate, and an acetic acid solution. After the reaction, the product is cooled, then vacuum filtered. The filter cake is washed and dried to obtain the multifunctional cashmere-based product. This preparation method first treats the cashmere to facilitate graft modification, then prepares modified chitosan, and finally uses the modified chitosan to modify the pre-treated cashmere, enhancing the antibacterial properties of the cashmere fiber. Simultaneously, it can fix quaternary ammonium salt groups onto the cashmere through chemical bonds, utilizing these groups to persistently disrupt the bacterial cell membranes of bacteria in contact with the cashmere, providing highly efficient bactericidal effects. Furthermore, the product is not easily lost, has high safety, and achieves a long-lasting antibacterial effect.

[0029] In the preparation of multifunctional fluff, a modified chitosan was first prepared. Formic acid and formaldehyde were used to convert the -NH2 group on the chitosan molecule to -N(CH3)2, yielding dimethylaminochitosan. Then, epichlorohydrin was used to treat the dimethylaminochitosan, converting some hydroxyl groups into ether bonds and introducing epoxy groups, and converting some tertiary amine groups into quaternary ammonium groups and introducing epoxy groups, yielding epoxy-quaternized chitosan. Finally, isophorone diisocyanate was used to treat the epoxy-quaternized chitosan, thereby adding ether bonds to the chitosan molecule. Modified chitosan is obtained by introducing a large number of isocyanate groups into the chitosan structure. The molecular structure of this modified chitosan contains a large number of epoxy groups and isocyanate groups, which have high reactivity. This allows the modified chitosan to be tightly grafted onto cashmere fibers in the form of chemical bonds. Furthermore, the introduction of a large number of quaternary ammonium groups can form a dense positively charged layer on the surface of cashmere fibers. When bacteria approach, they are strongly electrostatically adsorbed, and their cell membranes are destroyed, achieving the purpose of contact sterilization. Moreover, the quaternary ammonium salt is covalently fixed and is not easily lost, thus providing long-lasting and safe effects. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1:

[0032] This embodiment describes a method for preparing multifunctional cashmere based on modified chitosan grafted cashmere, including the following steps:

[0033] Step S1: Add 2g of cashmere, 20mL of 30% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 1mL:0.5g:90mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 25℃ and 200r / min for 3min. Then raise the temperature to 40℃ and continue stirring for 40min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake three times with distilled water and then place it in a vacuum drying oven and dry at 50℃ for 1h to obtain pretreated cashmere.

[0034] Step S2: Add 2g of pretreated cashmere and 20mL of 2% SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 25℃ and 200r / min for 10min. Then raise the temperature to 50℃ and continue stirring for 1h. After the reaction is complete, filter the reaction product while it is still hot. Soak the filter cake in distilled water at 90℃ for 15min, then vacuum filter. Place the filter cake in a vacuum drying oven and dry at 50℃ for 2h to obtain the pretreated cashmere.

[0035] Step S3: Add 15 mL of formic acid and 40 mL of deionized water to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir for 10 min at 25 °C and 200 r / min. Then add 3 g of chitosan with a degree of deacetylation of 90% and an average molecular weight of 10 kDa and continue stirring for 20 min. Then add 25 mL of 35% formaldehyde solution and heat to 70 °C and continue stirring for 20 h. After the reaction is complete, cool the reaction product to room temperature and adjust the pH to 9 with 35% sodium hydroxide solution. Then vacuum filter the product and wash the filter cake three times with distilled water. Then place it in a vacuum drying oven and dry at 40 °C for 3 h to obtain dimethylamino chitosan.

[0036] Step S4: Add 3g of dimethylaminochitosan, 10g of epichlorohydrin and 20mL of N-methyl-2-pyrrolidone to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 25℃ and 200r / min for 10min. Then raise the temperature to 60℃ and continue stirring for 3h. Then add 20mL of 20% sodium hydroxide solution and continue stirring for 2h. After the reaction is complete, cool the reaction product to room temperature and pour it into a mixed solution of ethanol and diethyl ether in equal volumes. Then vacuum filter and place the filter cake in a vacuum drying oven and dry at 40℃ for 2h to obtain epoxy quaternized chitosan.

[0037] Step S5: Add 5g of epoxy-quaternized chitosan, 1.2g of isophorone diisocyanate, 0.02g of dibutyltin dilaurate, 20mL of 1,4-dioxane, and 8mL of toluene to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 25℃ and 200r / min for 10min. Then raise the temperature to 70℃ and continue stirring for 2h. After the reaction is complete, cool the reaction product to room temperature, remove the solvent by rotary evaporation, wash three times with diethyl ether and distilled water, and then place it in a vacuum drying oven and dry at 40℃ for 3h to obtain modified chitosan.

[0038] Step S6: Add 5g of pre-treated cashmere, 1.6g of modified chitosan, 0.1g of dibutyltin dilaurate, and 90mL of 2% acetic acid solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 25℃ and 200r / min for 10min. Then raise the temperature to 50℃ and continue stirring for 2h. After that, raise the temperature to 80℃ and continue stirring for 30min. After the reaction is completed, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake three times with distilled water and then place it in a vacuum drying oven and dry at 50℃ for 3h to obtain multifunctional cashmere based on modified chitosan grafted cashmere.

[0039] Example 2:

[0040] This embodiment describes a method for preparing multifunctional cashmere based on modified chitosan grafted cashmere, including the following steps:

[0041] Step S1: Add 2g of cashmere, 22mL of 32% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 3mL:0.7g:95mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 28℃ and 250r / min for 4min. Then raise the temperature to 42℃ and continue stirring for 50min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake four times with distilled water and then place it in a vacuum drying oven and dry at 55℃ for 2h to obtain pretreated cashmere.

[0042] Step S2: Add 2g of pretreated cashmere and 22mL of 2.5% SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 28℃ and 250r / min for 12min. Then raise the temperature to 52℃ and continue stirring for 1.3h. After the reaction is complete, filter the reaction product while it is hot. Soak the filter cake in distilled water at 92℃ for 18min, then vacuum filter. Place the filter cake in a vacuum drying oven and dry at 55℃ for 3h to obtain the pretreated cashmere.

[0043] Step S3: Add 18 mL of formic acid and 45 mL of deionized water to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir for 12 min at 28 °C and 250 r / min. Then add 3 g of chitosan with a degree of deacetylation of 90% and an average molecular weight of 10 kDa and continue stirring for 22 min. Then add 28 mL of 36% formaldehyde solution and heat to 72 °C and continue stirring for 30 h. After the reaction is complete, cool the reaction product to room temperature and adjust the pH to 9.5 with 38% sodium hydroxide solution. Then vacuum filter and wash the filter cake 4 times with distilled water. Then place it in a vacuum drying oven and dry at 45 °C for 4 h to obtain dimethylamino chitosan.

[0044] Step S4: Add 3g of dimethylaminochitosan, 12g of epichlorohydrin, and 25mL of N-methyl-2-pyrrolidone to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 28℃ and 250r / min for 12min. Then raise the temperature to 62℃ and continue stirring for 4h. Add 25mL of 22% sodium hydroxide solution and continue stirring for 2.5h. After the reaction is complete, cool the reaction product to room temperature and pour it into a mixed solution of ethanol and diethyl ether in equal volumes. Then filter under vacuum and place the filter cake in a vacuum drying oven and dry at 45℃ for 2.5h to obtain epoxy quaternized chitosan.

[0045] Step S5: Add 5g of epoxy-quaternized chitosan, 1.5g of isophorone diisocyanate, 0.03g of dibutyltin dilaurate, 22mL of 1,4-dioxane, and 9mL of toluene to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 28℃ and 250r / min for 12min. Then raise the temperature to 72℃ and continue stirring for 2.5h. After the reaction is complete, cool the reaction product to room temperature, remove the solvent by rotary evaporation, wash with diethyl ether and distilled water four times in sequence, and then place it in a vacuum drying oven and dry at 42℃ for 4h to obtain modified chitosan.

[0046] Step S6: Add 5g of pre-treated cashmere, 2.7g of modified chitosan, 0.15g of dibutyltin dilaurate, and 95mL of 2.5% acetic acid solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 28℃ and 250r / min for 12min. Then raise the temperature to 55℃ and continue stirring for 2.5h. After that, raise the temperature to 85℃ and continue stirring for 40min. After the reaction is completed, cool the reaction product to room temperature, then vacuum filter. Wash the filter cake four times with distilled water and then place it in a vacuum drying oven and dry at 55℃ for 4h to obtain multifunctional cashmere based on modified chitosan grafted cashmere.

[0047] Example 3:

[0048] This embodiment describes a method for preparing multifunctional cashmere based on modified chitosan grafted cashmere, including the following steps:

[0049] Step S1: Add 2g of cashmere, 25mL of 35% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 5mL:0.9g:100mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 5min. Then raise the temperature to 45℃ and continue stirring for 60min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 3h to obtain pretreated cashmere.

[0050] Step S2: Add 2g of pretreated cashmere and 25mL of 3% SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 55℃ and continue stirring for 1.5h. After the reaction is complete, filter the reaction product while it is still hot. Soak the filter cake in distilled water at 95℃ for 20min, then filter under vacuum. Place the filter cake in a vacuum drying oven and dry at 60℃ for 4h to obtain the pretreated cashmere.

[0051] Step S3: Add 20 mL of formic acid and 50 mL of deionized water to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir for 15 min at 30 °C and 300 r / min. Then add 3 g of chitosan with a degree of deacetylation of 90% and an average molecular weight of 10 kDa and continue stirring for 25 min. Then add 30 mL of 37% formaldehyde solution and heat to 75 °C and continue stirring for 40 h. After the reaction is complete, cool the reaction product to room temperature and adjust the pH to 10 with 40% sodium hydroxide solution. Then vacuum filter and wash the filter cake 5 times with distilled water. Then place it in a vacuum drying oven and dry at 50 °C for 5 h to obtain dimethylamino chitosan.

[0052] Step S4: Add 3g of dimethylaminochitosan, 15g of epichlorohydrin and 30mL of N-methyl-2-pyrrolidone to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 65℃ and continue stirring for 5h. Then add 30mL of 25% sodium hydroxide solution and continue stirring for 3h. After the reaction is complete, cool the reaction product to room temperature and pour it into a mixed solution of ethanol and diethyl ether in equal volumes. Then vacuum filter and place the filter cake in a vacuum drying oven and dry at 50℃ for 3h to obtain epoxy quaternized chitosan.

[0053] Step S5: Add 5g of epoxy-quaternized chitosan, 1.8g of isophorone diisocyanate, 0.04g of dibutyltin dilaurate, 25mL of 1,4-dioxane, and 10mL of toluene to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 75℃ and continue stirring for 3h. After the reaction is complete, cool the reaction product to room temperature, remove the solvent by rotary evaporation, wash with diethyl ether and distilled water five times in sequence, and then place it in a vacuum drying oven and dry at 50℃ for 5h to obtain modified chitosan.

[0054] Step S6: Add 5g of pre-treated cashmere, 3.8g of modified chitosan, 0.2g of dibutyltin dilaurate, and 100mL of 3% acetic acid solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 60℃ and continue stirring for 3h. After that, raise the temperature to 90℃ and continue stirring for 50min. After the reaction is completed, cool the reaction product to room temperature, then vacuum filter. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 5h to obtain multifunctional cashmere based on modified chitosan grafted cashmere.

[0055] Comparative Example 1:

[0056] This comparative example illustrates a method for preparing multifunctional plush, comprising the following steps:

[0057] Step S1: Add 2g of cashmere, 25mL of 35% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 5mL:0.9g:100mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 5min. Then raise the temperature to 45℃ and continue stirring for 60min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 3h to obtain pretreated cashmere.

[0058] Step S2: Add 2g of pretreated cashmere and 25mL of 3% (w / w) SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 55℃ and continue stirring for 1.5h. After the reaction is complete, filter the product while it is still hot. Soak the filter cake in distilled water at 95℃ for 20min, then vacuum filter. Place the filter cake in a vacuum drying oven and dry at 60℃ for 4h to obtain multifunctional cashmere.

[0059] Comparative Example 2:

[0060] This comparative example illustrates a method for preparing multifunctional plush, comprising the following steps:

[0061] Step S1: Add 2g of cashmere, 25mL of 35% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 5mL:0.9g:100mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 5min. Then raise the temperature to 45℃ and continue stirring for 60min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 3h to obtain pretreated cashmere.

[0062] Step S2: Add 2g of pretreated cashmere and 25mL of 3% SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 55℃ and continue stirring for 1.5h. After the reaction is complete, filter the reaction product while it is still hot. Soak the filter cake in distilled water at 95℃ for 20min, then filter under vacuum. Place the filter cake in a vacuum drying oven and dry at 60℃ for 4h to obtain the pretreated cashmere.

[0063] Step S3: Add 5g of pre-treated cashmere, 3.8g of chitosan with a degree of deacetylation of 90% and an average molecular weight of 10kDa, 0.2g of dibutyltin dilaurate, and 100mL of acetic acid solution with a mass fraction of 3% to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and a stirring rate of 300r / min for 15min. Then raise the temperature to 60℃ and continue stirring for 3h. After that, raise the temperature to 90℃ and continue stirring for 50min. After the reaction is completed, cool the reaction product to room temperature, then vacuum filter. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 5h to obtain multifunctional cashmere.

[0064] Comparative Example 3:

[0065] This comparative example illustrates a method for preparing multifunctional plush, comprising the following steps:

[0066] Step S1: Add 2g of cashmere, 25mL of 35% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 5mL:0.9g:100mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 5min. Then raise the temperature to 45℃ and continue stirring for 60min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 3h to obtain pretreated cashmere.

[0067] Step S2: Add 2g of pretreated cashmere and 25mL of 3% SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 55℃ and continue stirring for 1.5h. After the reaction is complete, filter the reaction product while it is still hot. Soak the filter cake in distilled water at 95℃ for 20min, then filter under vacuum. Place the filter cake in a vacuum drying oven and dry at 60℃ for 4h to obtain the pretreated cashmere.

[0068] Step S3: Add 5g of chitosan with a degree of deacetylation of 90% and an average molecular weight of 10kDa, 1.8g of isophorone diisocyanate, 0.04g of dibutyltin dilaurate, 25mL of 1,4-dioxane, and 10mL of toluene to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 75℃ and continue stirring for 3h. After the reaction is complete, cool the reaction product to room temperature, then remove the solvent by rotary evaporation. Then wash with diethyl ether and distilled water five times in sequence. Then place it in a vacuum drying oven and dry at 50℃ for 5h to obtain modified chitosan.

[0069] Step S4: Add 5g of pre-treated cashmere, 3.8g of modified chitosan, 0.2g of dibutyltin dilaurate, and 100mL of 3% acetic acid solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 60℃ and continue stirring for 3h. After that, raise the temperature to 90℃ and continue stirring for 50min. After the reaction is complete, cool the reaction product to room temperature, then vacuum filter. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 5h to obtain multifunctional cashmere.

[0070] Comparative Example 4:

[0071] This comparative example illustrates a method for preparing multifunctional plush, comprising the following steps:

[0072] Step S1: Add 2g of cashmere, 25mL of 35% hydrogen peroxide, sodium silicate, and deionized water in a ratio of 5mL:0.9g:100mL to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 5min. Then raise the temperature to 45℃ and continue stirring for 60min. After the reaction is complete, cool the reaction product to room temperature and then filter under vacuum. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 3h to obtain pretreated cashmere.

[0073] Step S2: Add 2g of pretreated cashmere and 25mL of 3% SAVINASE 8.0T proteinase solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 55℃ and continue stirring for 1.5h. After the reaction is complete, filter the reaction product while it is still hot. Soak the filter cake in distilled water at 95℃ for 20min, then filter under vacuum. Place the filter cake in a vacuum drying oven and dry at 60℃ for 4h to obtain the pretreated cashmere.

[0074] Step S3: Add 20 mL of formic acid and 50 mL of deionized water to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir for 15 min at 30 °C and 300 r / min. Then add 3 g of chitosan with a degree of deacetylation of 90% and an average molecular weight of 10 kDa and continue stirring for 25 min. Then add 30 mL of 37% formaldehyde solution and heat to 75 °C and continue stirring for 40 h. After the reaction is complete, cool the reaction product to room temperature and adjust the pH to 10 with 40% sodium hydroxide solution. Then vacuum filter and wash the filter cake 5 times with distilled water. Then place it in a vacuum drying oven and dry at 50 °C for 5 h to obtain dimethylamino chitosan.

[0075] Step S4: Add 3g of dimethylaminochitosan, 15g of epichlorohydrin and 30mL of N-methyl-2-pyrrolidone to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 65℃ and continue stirring for 5h. Then add 30mL of 25% sodium hydroxide solution and continue stirring for 3h. After the reaction is complete, cool the reaction product to room temperature and pour it into a mixed solution of ethanol and diethyl ether in equal volumes. Then vacuum filter and place the filter cake in a vacuum drying oven and dry at 50℃ for 3h to obtain epoxy quaternized chitosan.

[0076] Step S5: Add 5g of pre-treated cashmere, 3.8g of epoxy-quaternized chitosan, 0.2g of dibutyltin dilaurate, and 100mL of 3% acetic acid solution to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir at 30℃ and 300r / min for 15min. Then raise the temperature to 60℃ and continue stirring for 3h. After that, raise the temperature to 90℃ and continue stirring for 50min. After the reaction is complete, cool the reaction product to room temperature, then vacuum filter. Wash the filter cake 5 times with distilled water and then place it in a vacuum drying oven and dry at 60℃ for 5h to obtain multifunctional cashmere.

[0077] The multifunctional fleece products of Examples 1-3 and Comparative Examples 1-4 were subjected to antibacterial rate testing according to GB / T 20944.3-2008, with Staphylococcus aureus as the test strain. They were then washed according to AATCC 135, and the antibacterial rate was tested after 20 washes. The test results are shown in the table below:

[0078]

[0079] Referring to the data in the table above, and based on the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that the multifunctional fluff of this application has excellent antibacterial properties and antibacterial property retention effect.

[0080] Among them, comparing Example 3 and Comparative Example 1, it can be found that the antibacterial performance of the multifunctional fluff without chitosan treatment is poor; comparing Example 3, Comparative Example 1, and Comparative Example 2, it can be found that the multifunctional fluff treated with chitosan has better antibacterial performance than the multifunctional fluff without chitosan treatment, but the performance improvement effect of unmodified chitosan is significant; comparing Example 3, Comparative Example 2, and Comparative Example 3, it can be found that the multifunctional fluff treated with chitosan containing isocyanate groups has better antibacterial performance than the multifunctional fluff treated with chitosan alone, but the performance improvement effect of unmodified chitosan is significant; comparing Example 3, Comparative Example 2, Comparative Example 3, and Comparative Example 4, it can be found that the multifunctional fluff treated with chitosan containing epoxy groups and quaternary ammonium groups has better antibacterial performance than the multifunctional fluff treated with chitosan and the multifunctional fluff treated with chitosan containing isocyanate groups, but the performance improvement effect of unmodified chitosan is significant.

[0081] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0082] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing multifunctional cashmere based on modified chitosan grafted cashmere, characterized in that, Includes the following steps: The pre-treated cashmere, modified chitosan, dibutyltin dilaurate and acetic acid solution were stirred and reacted. After the reaction was completed, the reaction product was cooled and then vacuum filtered. The filter cake was washed and dried to obtain multifunctional cashmere based on modified chitosan grafted cashmere. The pre-treated cashmere is prepared by the following steps: Step a1: Stir the cashmere and cashmere treatment solution to react. After the reaction is complete, cool the reaction product, then filter it under vacuum. Wash and dry the filter cake to obtain pretreated cashmere. Step a2: The pretreated cashmere and protease solution are stirred and reacted. After the reaction is completed, the reaction product is filtered while hot. The filter cake is added to distilled water for soaking, then vacuum filtered and the filter cake is dried to obtain the pretreated cashmere.

2. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 1, characterized in that, The ratio of the initial treatment cashmere, modified chitosan, dibutyltin dilaurate, and acetic acid solution is 5g:1.6-3.8g:0.1-0.2g:90-100mL; the mass fraction of the acetic acid solution is 2-3%.

3. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 1, characterized in that, In step a1, the ratio of cashmere to cashmere treatment solution is 2g: 20-25mL; the cashmere treatment solution is a mixture of hydrogen peroxide, sodium silicate, and deionized water in a ratio of 1-5mL: 0.5-0.9g: 90-100mL; the mass fraction of hydrogen peroxide is 30-35%.

4. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 1, characterized in that, In step a2, the ratio of the pretreated cashmere to the protease solution is 2g:20-25mL; the mass fraction of the protease solution is 2-3%; and the protease is SAVINASE 8.0T.

5. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 1, characterized in that, The modified chitosan was prepared by the following steps: Step b1: Formic acid and deionized water are stirred and reacted, then chitosan and formaldehyde solution are added and the reaction is continued. After the reaction is completed, the reaction product is cooled, then the pH is adjusted with sodium hydroxide solution, and then vacuum filtered. The filter cake is washed and dried to obtain dimethylaminochitosan. Step b2: Adjust the reaction mixture of dimethylaminochitosan, epichlorohydrin and N-methyl-2-pyrrolidone to a stirring state, then add sodium hydroxide solution and continue stirring. After the reaction is complete, cool the reaction product and pour it into a mixed solution. Then filter under vacuum and dry the filter cake to obtain epoxy-quaternized chitosan. Step b3: Epoxy-quaternized chitosan, isophorone diisocyanate, dibutyltin dilaurate, 1,4-dioxane, and toluene are stirred and reacted. After the reaction is completed, the reaction product is cooled, then rotary evaporated, washed, and dried to obtain modified chitosan.

6. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 5, characterized in that, In step b1, the ratio of formic acid, deionized water, chitosan, and formaldehyde solution is 15-20 mL: 40-50 mL: 3 g: 25-30 mL; the degree of deacetylation of the chitosan is 90%, and the average molecular weight is 10 kDa; the mass fraction of the formaldehyde solution is 35-37%; and the mass fraction of the sodium hydroxide solution is 35-40%.

7. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 5, characterized in that, In step b2, the ratio of dimethylaminochitosan, epichlorohydrin, N-methyl-2-pyrrolidone, and sodium hydroxide solution is 3g:10-15g:20-30mL:20-30mL; the mass fraction of the sodium hydroxide solution is 20-25%; and the mixed solution is prepared by mixing ethanol and diethyl ether in equal volumes.

8. The method for preparing multifunctional cashmere based on modified chitosan grafted cashmere according to claim 5, characterized in that, In step b3, the ratio of epoxy quaternized chitosan, isophorone diisocyanate, dibutyltin dilaurate, 1,4-dioxane, and toluene is 5g:1.2-1.8g:0.02-0.04g:20-25mL:8-10mL.

9. A multifunctional fleece based on modified chitosan-grafted cashmere, characterized in that, The multifunctional cashmere based on modified chitosan grafted cashmere was prepared using the preparation method described in any one of claims 1-8.

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