Antibacterial viscose fiber and preparation method thereof

Abstract

The invention relates to an antibacterial viscose fiber and a preparation method thereof, the preparation method of the antibacterial viscose fiber comprises the following steps: S1, adding octenyl succinic starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester into water to obtain an emulsion; the emulsion is subjected to spray drying, and microcapsules are obtained; s2, microcapsules and benzoyl peroxide are added into ethyl acetate, and an ethyl acetate solution is obtained; s3, putting viscose fibers in water for swelling, then washing and drying, then putting the viscose fibers in an acetic ether solution in a protective gas atmosphere for grafting reaction, and then washing and drying to obtain the antibacterial viscose fibers. According to the invention, the origanum essential oil with an antibacterial effect is introduced into the viscose fiber in a chemical bonding manner, so that the bonding strength of the origanum essential oil and the viscose fiber is improved, and the durability of the antibacterial effect is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of textiles, and particularly relates to an antibacterial viscose fiber and a preparation method thereof. Background Art

[0002] Viscose fiber, also known as viscose silk, is a type of cellulose fiber. Viscose fiber is made from natural fibers such as wood fiber and cotton staple fiber. It is made into soluble cellulose xanthate through alkalization, aging, sulfonation and other processes. The soluble cellulose xanthate is then dissolved in dilute alkali solution to make viscose, and then made into artificial fiber through wet spinning process. The basic composition of viscose fiber is cellulose (C6H10O5)n, which has strong hygroscopicity (moisture regain is about 13%), and it expands significantly after absorbing moisture, and the diameter increases by up to 50%. It has strong spinnability, and the fabrics made are soft, smooth, comfortable, and warm. It is widely used in the production of clothing, decorative items, household textiles, etc.

[0003] In recent years, with the advancement of science and technology, functional fibers and functional textiles have emerged. Functional fibers and functional textiles refer to fibers and textiles that have some special functions in addition to physical and mechanical properties, such as protective functions (such as flame retardant, antistatic, anti-ultraviolet) fibers and textiles, and antibacterial fibers and textiles.

[0004] In order to give fabrics antibacterial properties, they are usually treated through post-finishing processes. Specifically, the grey fabric is post-finished with a finishing liquid made of antibacterial agents, thereby giving the fabrics antibacterial properties. However, the antibacterial stability of fabrics made in this way is poor, and the antibacterial agents are easily lost during the washing process, resulting in a decrease in the antibacterial effect. Summary of the invention

[0005] In view of this, the object of the present invention is to provide an antibacterial viscose fiber and a preparation method thereof, so as to solve the above-mentioned technical problems such as poor stability of antibacterial efficacy and easy loss of antibacterial agents during washing, resulting in reduced antibacterial effect.

[0006] To achieve the above-mentioned object of the invention, the technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a method for preparing an antibacterial viscose fiber, comprising the following steps:

[0008] S1. Octenyl succinate starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester were added to water to obtain an emulsion;

[0009] spray drying the emulsion to obtain microcapsules;

[0010] S2. adding the microcapsules and benzoyl peroxide to ethyl acetate to obtain an ethyl acetate solution;

[0011] S2. The viscose fiber is placed in water to swell, then washed and dried, and then placed in the ethyl acetate solution under a protective gas atmosphere to carry out a grafting reaction, and then washed and dried to obtain the antibacterial viscose fiber.

[0012] Optionally, in step S1, the mass ratio of octenyl succinate starch ester to oregano essential oil is 2-4:1, preferably 2.5-4:1.

[0013] Optionally, in step S1, the mass ratio of the polyoxyethylene sorbitan fatty acid ester to the oregano essential oil is 0.02-0.05:1, preferably 0.03-0.05:1.

[0014] Optionally, in the emulsion of step S1, the concentration of the oregano essential oil is 4wt%-9wt%, preferably 5wt%-9wt%.

[0015] Optionally, in step S1, during the spray drying process, the inlet air temperature is 120-140°C, preferably 125-140°C; the compressed air flow rate is 5-8L / min, preferably 6-8L / min; and the feed amount is 0.01-0.02L / min, preferably 0.015-0.02L / min.

[0016] Optionally, in step S2, the mass ratio of the microcapsules to benzoyl peroxide is 1:0.002-0.005, preferably 1:0.003-0.005.

[0017] Optionally, in the ethyl acetate solution in step S2, the concentration of the microcapsules is 2wt%-6wt%, preferably 3wt%-6wt%.

[0018] Optionally, 2,2,6,6-tetramethyl-1-piperidinoxide is also added to the ethyl acetate solution in step S2.

[0019] Optionally, in step S2, the mass ratio of the 2,2,6,6-tetramethyl-1-piperidinyl oxide to benzoyl peroxide is 0.001-0.003:0.002-0.005, preferably 0.0015-0.003:0.002-0.005.

[0020] Optionally, water is also added to the ethyl acetate solution in step S2.

[0021] Optionally, in step S2, the mass ratio of water to benzoyl peroxide is 0.002-0.003:0.002-0.005, preferably 0.0025-0.003:0.002-0.005.

[0022] Optionally, in step S3, the swelling time is 20-30 min, preferably 25-30 min.

[0023] Optionally, in step S3, the drying temperature is 50-60°C, preferably 55-60°C; the drying time is 10-20 min, preferably 15-20 min.

[0024] Optionally, in step S3, the temperature of the grafting reaction is 95-105° C., preferably 100-105° C.; the duration of the grafting reaction is 60-90 min, preferably 75-90 min.

[0025] Optionally, in step S3, the mass ratio of the viscose fiber to the ethyl acetate solution is 1:15-20, preferably 1:18-20.

[0026] Optionally, in step S3, the drying temperature is 50-60°C, preferably 55-60°C; the drying time is 10-20 min, preferably 15-20 min.

[0027] In a second aspect, the present invention also provides an antibacterial viscose fiber prepared according to the method as described above.

[0028] As described above, the antibacterial viscose fiber and the preparation method thereof of the present invention have the following beneficial effects:

[0029] In the present invention, oregano essential oil with antibacterial efficacy is used as a core material, octenyl succinate starch ester is used as a wall material, and polyoxyethylene sorbitan fatty acid ester is used as an emulsifier, and microcapsules are prepared by spray drying; then benzoyl peroxide is used as an initiator, and the benzoyl peroxide is decomposed by heat to generate free radicals, which initiate a grafting reaction, and the octenyl succinate starch ester contained in the wall material of the microcapsule is used as a grafting monomer to undergo a grafting reaction with viscose fiber, and the microcapsule is grafted onto the viscose fiber, that is, the oregano essential oil with antibacterial efficacy is introduced into the viscose fiber by chemical bonding, thereby improving the bonding strength between the oregano essential oil and the viscose fiber, and further improving the durability of the antibacterial efficacy.

[0030] In the present invention, 2,2,6,6-tetramethyl-1-piperidinyl oxide can reduce the activation energy of benzoyl peroxide, accelerate the decomposition of benzoyl peroxide, and then generate more free radicals, increase the grafting rate, and further enhance the antibacterial performance.

[0031] In the present invention, water can promote the melting process of benzoyl peroxide, thereby promoting the early decomposition of benzoyl peroxide, increasing the grafting rate, and further improving the antibacterial performance. DETAILED DESCRIPTION

[0032] The present invention is further described below through specific examples, but it should be pointed out that the specific material ratios, process conditions and results described in the embodiments of the present invention are only used to illustrate the present invention and cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention. Unless otherwise specified, "wt%" refers to the mass percentage.

[0033] An embodiment of the present invention provides a method for preparing antibacterial viscose fiber, comprising the following steps:

[0034] S1. Adding octenyl succinate starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester to water to obtain an emulsion having a concentration of 4wt%-9wt% of oregano essential oil; the mass ratio of polyoxyethylene sorbitan fatty acid ester to oregano essential oil is 0.02-0.05:1, and the mass ratio of octenyl succinate starch ester to oregano essential oil is 2-4:1;

[0035] The emulsion is spray-dried under the conditions of an inlet air temperature of 120-140° C., a compressed air flow rate of 5-8 L / min, and a feed amount of 0.01-0.02 L / min to obtain microcapsules;

[0036] S2. Adding microcapsules and benzoyl peroxide to ethyl acetate to obtain a solution of ethyl acetate having a concentration of 2wt%-6wt% of microcapsules, wherein the mass ratio of microcapsules to benzoyl peroxide is 1:0.002-0.005;

[0037] S2. The viscose fiber is placed in water to swell for 20-30 minutes, then washed, dried at 50-60°C for 10-20 minutes, and then placed in ethyl acetate solution under a protective gas atmosphere at 95-105°C for grafting reaction for 60-90 minutes, wherein the mass ratio of the viscose fiber to the ethyl acetate solution is 1:15-20; then washed, and dried at 50-60°C for 10-20 minutes to obtain the antibacterial viscose fiber.

[0038] In another embodiment of the present invention, 2,2,6,6-tetramethyl-1-piperidinyl oxide is further added to the ethyl acetate solution in step S2, and the mass ratio of 2,2,6,6-tetramethyl-1-piperidinyl oxide to benzoyl peroxide is 0.001-0.003:0.002-0.005.

[0039] In another embodiment of the present invention, water is further added to the ethyl acetate solution in step S2, and the mass ratio of water to benzoyl peroxide is 0.002-0.003:0.002-0.005.

[0040] Another embodiment of the present invention also provides an antibacterial viscose fiber prepared according to the method as described above.

[0041] The present invention is described in detail below by specific examples. It should also be understood that the following examples are only used to specifically illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention belong to the scope of protection of the present invention. The specific process parameters and the like in the following examples are also only examples within a suitable range, that is, those skilled in the art can make a selection within a suitable range through the description herein, and are not limited to the specific values ​​​​exemplified below.

[0042] Example 1

[0043] A method for preparing antibacterial viscose fiber, the specific steps are as follows:

[0044] S1. Octenyl succinate starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester were added to pure water to obtain an emulsion having a concentration of 9 wt % of oregano essential oil; the mass ratio of polyoxyethylene sorbitan fatty acid ester to oregano essential oil was 0.02:1; the mass ratio of octenyl succinate starch ester to oregano essential oil was 4:1;

[0045] The emulsion was spray-dried under the conditions of an inlet air temperature of 120°C, a compressed air flow rate of 5 L / min and a feed amount of 0.01 L / min to obtain microcapsules;

[0046] S2. Adding microcapsules and benzoyl peroxide to ethyl acetate to obtain a 6 wt % ethyl acetate solution of microcapsules, the mass ratio of microcapsules to benzoyl peroxide being 1:0.005;

[0047] S2. Place the viscose fiber in pure water 10 times its mass to swell for 30 minutes, wash, and then dry at 60°C for 10 minutes. Then, place the viscose fiber in ethyl acetate solution under a nitrogen atmosphere at 105°C for grafting reaction for 60 minutes. The mass ratio of viscose fiber (here refers to the mass before swelling treatment) to ethyl acetate solution is 1:15; then wash and dry at 60°C for 20 minutes to obtain antibacterial viscose fiber.

[0048] Example 2

[0049] A method for preparing antibacterial viscose fiber, the specific steps are as follows:

[0050] S1. Adding octenyl succinate starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester to pure water to obtain an emulsion having a concentration of 4 wt % of oregano essential oil; the mass ratio of polyoxyethylene sorbitan fatty acid ester to oregano essential oil is 0.05:1; the mass ratio of octenyl succinate starch ester to oregano essential oil is 2:1;

[0051] The emulsion was spray-dried under the conditions of an inlet air temperature of 140°C, a compressed air flow rate of 8 L / min and a feed amount of 0.02 L / min to obtain microcapsules;

[0052] S2. Adding microcapsules and benzoyl peroxide to ethyl acetate to obtain a 2 wt % ethyl acetate solution of microcapsules, the mass ratio of microcapsules to benzoyl peroxide being 1:0.002;

[0053] S2. Place the viscose fiber in pure water 15 times its mass to swell for 20 minutes, wash, and then dry at 50°C for 20 minutes. Then, place the viscose fiber in ethyl acetate solution under a nitrogen atmosphere at 95°C for grafting reaction for 90 minutes. The mass ratio of viscose fiber (here refers to the mass before swelling treatment) to ethyl acetate solution is 1:20; then wash and dry at 50°C for 10 minutes to obtain antibacterial viscose fiber.

[0054] Example 3

[0055] A method for preparing antibacterial viscose fiber, the specific steps are as follows:

[0056] S1. Adding octenyl succinate starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester to pure water to obtain an emulsion having a concentration of 6 wt % of oregano essential oil; the mass ratio of polyoxyethylene sorbitan fatty acid ester to oregano essential oil is 0.04:1; the mass ratio of octenyl succinate starch ester to oregano essential oil is 3:1;

[0057] The emulsion was spray-dried under the conditions of an inlet air temperature of 130°C, a compressed air flow rate of 6 L / min and a feed amount of 0.015 L / min to obtain microcapsules;

[0058] S2. Adding microcapsules and benzoyl peroxide to ethyl acetate to obtain a 4 wt % ethyl acetate solution of microcapsules, the mass ratio of microcapsules to benzoyl peroxide being 1:0.003;

[0059] S2. Place the viscose fiber in pure water 12 times its mass to swell for 25 minutes, wash, and then dry at 55°C for 16 minutes. Then, place the viscose fiber in ethyl acetate solution under a nitrogen atmosphere at 100°C for grafting reaction for 75 minutes. The mass ratio of viscose fiber (here refers to the mass before swelling treatment) to ethyl acetate solution is 1:18; then wash and dry at 55°C for 15 minutes to obtain antibacterial viscose fiber.

[0060] Example 4

[0061] The antibacterial viscose fiber was prepared in the same manner as in Example 3 except for the following conditions:

[0062] S2. Add microcapsules, benzoyl peroxide and 2,2,6,6-tetramethyl-1-piperidinyl oxide to ethyl acetate to obtain an ethyl acetate solution with a microcapsule concentration of 4 wt %, a mass ratio of microcapsules to benzoyl peroxide of 1:0.003, and a mass ratio of 2,2,6,6-tetramethyl-1-piperidinyl oxide to benzoyl peroxide of 0.001:0.003.

[0063] Example 5

[0064] The antibacterial viscose fiber was prepared in the same manner as in Example 3 except for the following conditions:

[0065] S2. Add microcapsules, benzoyl peroxide and 2,2,6,6-tetramethyl-1-piperidinyl oxide to ethyl acetate to obtain an ethyl acetate solution with a microcapsule concentration of 4 wt %, a mass ratio of microcapsules to benzoyl peroxide of 1:0.003, and a mass ratio of 2,2,6,6-tetramethyl-1-piperidinyl oxide to benzoyl peroxide of 0.003:0.003.

[0066] Example 6

[0067] The antibacterial viscose fiber was prepared in the same manner as in Example 3 except for the following conditions:

[0068] S2. Add microcapsules, benzoyl peroxide and pure water to ethyl acetate to obtain an ethyl acetate solution with a microcapsule concentration of 4 wt %, and the mass ratio of pure water to benzoyl peroxide is 0.002:0.003.

[0069] Example 7

[0070] The antibacterial viscose fiber was prepared in the same manner as in Example 3 except for the following conditions:

[0071] S2. Add microcapsules, benzoyl peroxide and pure water to ethyl acetate to obtain an ethyl acetate solution with a microcapsule concentration of 4 wt %, and the mass ratio of pure water to benzoyl peroxide is 0.003:0.003.

[0072] Comparative Example 1

[0073] The viscose fiber has the same source as that in Example 3, that is, it has not been subjected to swelling, drying, grafting reaction, washing, and drying treatments.

[0074] Antibacterial performance testing

[0075] The antibacterial viscose fibers prepared in Examples 1-7 and the viscose fibers of Comparative Example 1 were made into fabrics respectively, and 10 cm*10 cm samples were taken from each sample. The antibacterial value of each sample against Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC 1122938) was tested according to "GB / T 20944.2-2007 Evaluation of antibacterial properties of textiles Part 2: Absorption method", wherein the test bacterial solution was prepared after being cultured according to the culture C method, and the results are shown in Table 1;

[0076] Subsequently, each group of samples was machine washed at room temperature, the washing time was 10 minutes, the water level was full, the stirring speed was 180r / min, the spin speed was 650r / min, the spin time was 6 minutes, and then naturally air-dried. After 50 cycles of washing and air-drying, the antibacterial values ​​of each sample against Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC 1122938) were tested again in accordance with "GB / T 20944.2-2007 Evaluation of antibacterial properties of textiles Part 2: Absorption method", and the results are shown in Table 1.

[0077] Table 1 Antibacterial performance test results

[0078]

[0079] As shown in Table 1, before and after washing, the antibacterial values ​​of the fabrics made of the antibacterial viscose fibers of Examples 1-7 against Staphylococcus aureus and Escherichia coli did not change significantly. The results show that in the present invention, oregano essential oil with antibacterial efficacy is used as the core material, octenyl succinate starch ester is used as the wall material, and polyoxyethylene sorbitan fatty acid ester is used as the emulsifier, and microcapsules are prepared by spray drying; then benzoyl peroxide is used as the initiator, and benzoyl peroxide is decomposed by heat to produce free radicals, which can trigger a grafting reaction, and octenyl succinate starch ester contained in the wall material of the microcapsule is used as the grafting monomer, which undergoes a grafting reaction with the viscose fiber, and the microcapsules are grafted onto the viscose fiber, that is, the oregano essential oil with antibacterial efficacy is introduced into the viscose fiber by chemical bonding, which improves the bonding strength between the oregano essential oil and the viscose fiber, thereby improving the durability of the antibacterial efficacy.

[0080] As shown in Table 1, for the samples before washing, the antibacterial values ​​of the fabrics made of antibacterial viscose fibers of Examples 4 and 5 against Staphylococcus aureus and Escherichia coli were significantly improved compared with Example 3. The results show that in the present invention, 2,2,6,6-tetramethyl-1-piperidinyl oxide can reduce the activation energy of benzoyl peroxide, accelerate the decomposition of benzoyl peroxide, and then generate more free radicals, increase the grafting rate, and further improve the antibacterial performance.

[0081] As shown in Table 1, for the samples before washing, the antibacterial values ​​of the fabrics made of antibacterial viscose fibers of Examples 6 and 7 against Staphylococcus aureus and Escherichia coli were significantly improved compared with Example 3. This result shows that in the present invention, water can promote the melting process of benzoyl peroxide, thereby promoting the early decomposition of benzoyl peroxide, increasing the grafting rate, and further improving the antibacterial performance.

[0082] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for preparing antibacterial viscose fiber, characterized in that: The following steps are involved: S1. Octenyl succinate starch ester, oregano essential oil and polyoxyethylene sorbitan fatty acid ester were added to water to obtain an emulsion; spray drying the emulsion to obtain microcapsules; S2. adding the microcapsules and benzoyl peroxide to ethyl acetate to obtain an ethyl acetate solution; S3. The viscose fiber is placed in water to swell, then washed and dried, and then placed in the ethyl acetate solution under a protective gas atmosphere for grafting reaction, followed by washing and drying to obtain the antibacterial viscose fiber.

2. The preparation method according to claim 1, characterized in that: In step S1, the mass ratio of octenyl succinate starch ester to oregano essential oil is 2-4:1; And / or, in step S1, the mass ratio of the polyoxyethylene sorbitan fatty acid ester to the oregano essential oil is 0.02-0.05:1; And / or, in the emulsion of step S1, the concentration of oregano essential oil is 4wt%-9wt%; And / or, in step S1, during the spray drying process, the inlet air temperature is 120-140°C, the compressed air flow rate is 5-8 L / min, and the feed amount is 0.01-0.02 L / min.

3. The preparation method according to claim 1, characterized in that: In step S2, the mass ratio of the microcapsules to benzoyl peroxide is 1:0.002-0.005; And / or, in the ethyl acetate solution in step S2, the concentration of the microcapsules is 2wt%-6wt%.

4. The preparation method according to claim 1, characterized in that: In step S2, 2,2,6,6-tetramethyl-1-piperidinoxide is also added to the ethyl acetate solution.

5. The preparation method according to claim 4, characterized in that: In step S2, the mass ratio of the 2,2,6,6-tetramethyl-1-piperidinyl oxide to benzoyl peroxide is 0.001-0.003:0.002-0.

005.

6. The preparation method according to claim 1, characterized in that: Water is also added to the ethyl acetate solution in step S2.

7. The preparation method according to claim 6, characterized in that: In step S2, the mass ratio of water to benzoyl peroxide is 0.002-0.003:0.002-0.

005.

8. The preparation method according to claim 1, characterized in that: In step S3, the swelling time is 20-30 minutes; And / or, in step S3, the drying temperature is 50-60° C., and the drying time is 10-20 min.

9. The preparation method according to claim 1, characterized in that: In step S3, the temperature of the grafting reaction is 95-105° C., and the duration of the grafting reaction is 60-90 min; and / or, in step S3, the mass ratio of the viscose fiber to the ethyl acetate solution is 1:15-20; And / or, in step S3, the drying temperature is 50-60° C., and the drying time is 10-20 min.

10. Antibacterial viscose fiber prepared according to the method according to any one of claims 1 to 9.

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