CN112458564A

CN112458564A - Lyocell fiber containing wormwood/radix isatidis/tea extract and preparation method thereof

Info

Publication number: CN112458564A
Application number: CN202011234932.4A
Authority: CN
Inventors: 黄效华; 甄丽; 穆伟华
Original assignee: Qingdao Baicao New Material Co ltd; Zhongke Textile Research Institute Qingdao Co ltd; Bestee Material Qingdao Co ltd
Current assignee: Qingdao Baicao New Material Co ltd; Zhongke Textile Research Institute Qingdao Co ltd; Bestee Material Qingdao Co ltd
Priority date: 2020-11-08
Filing date: 2020-11-08
Publication date: 2021-03-09

Abstract

The invention provides a Lyocell fiber containing wormwood/isatis root/tea and a preparation method thereof, and is characterized in that the Lyocell fiber is prepared by modifying porous molecular nest containing wormwood/isatis root/tea extract and polyvinyl alcohol (PVA); the addition amount of the wormwood/isatis root/tea extract in the porous molecular nest in the production process accounts for 1-5wt% of the total amount of the cellulose and polyvinyl alcohol raw materials, and the ratio of the addition amount of the polyvinyl alcohol (PVA) to the addition amount of the cellulose is 1: 9-1: 1. the preparation comprises the following steps of S1, preparing a plant extract; s2, preparing a porous molecular nest; s3, preparing a porous molecular nest PVA adhesive film; s4, preparing the composite Lyocell fiber. According to the invention, natural effective components of the wormwood, the isatis root and the tea with antibacterial, antiviral and antioxidant effects are introduced into the fiber, so that the fiber has good antibacterial effect and biocompatibility, and is very suitable for special textile materials for medical treatment and health care.

Description

Lyocell fiber containing wormwood/radix isatidis/tea extract and preparation method thereof

Technical Field

The invention relates to the technical field of fibers, in particular to a composite Lyocell fiber containing a plant functional porous molecular nest of wormwood, isatis root and tea extract and a preparation method thereof.

Background

The Lyocell fiber is a cellulose fiber prepared by dissolving natural fiber pulp of wood, cotton, bamboo and the like in an organic solvent N-methylmorpholine-N-oxide through dry-jet wet spinning, and has the advantages of high dry strength and wet strength, good washing stability, excellent hygroscopicity, soft hand feeling and the like. In addition, the Lyocell fiber uses natural renewable cellulose resources, and the spinning process is simple and clean, so the Lyocell fiber is known as a novel green fiber material with excellent performance, the technical development is rapid, the Lyocell fiber is favored by consumers and is widely applied to various fields.

Especially the characteristic of high wet strength, so that the wet strength is very suitable for special application fields of medical care, health care and the like. However, cellulose molecules have a hydrophilic structure, are favorable media for microbial propagation, and are very easy to breed in a moist and warm environment in a medical care site. Therefore, the Chinese patent applications 201310559409.2, Lyocell fiber with multiple functions and the preparation method thereof, 201410142561.5, Lyocell fiber containing nanoparticles and the like all try to add functional components with special effects such as antibiosis and the like into the fiber to enrich and improve the use function of the fiber. However, most of the above prior arts simply mix inorganic fine particles or organic small molecules into fibers, and have problems of single function and poor biocompatibility. The spinning solvent N-methylmorpholine-N-oxide has strong oxidizing property, and the addition of organic functional components into the spinning solvent often causes side reactions to influence the product performance. Therefore, the market is demanding a technology capable of introducing natural functional materials to further broaden the functions of the existing products.

Disclosure of Invention

The invention aims to provide a composite Lyocell fiber of a plant functional porous molecular nest of wormwood, isatis root and tea and a preparation method thereof, so that the Lyocell fiber obtains good antibacterial and bacteriostatic properties and mechanical properties.

The technical scheme of the invention is realized as follows:

a Lyocell fiber containing folium Artemisiae Argyi/radix Isatidis/folium Camelliae sinensis and its preparation method are characterized by comprising porous molecular nest containing folium Artemisiae Argyi/radix Isatidis/folium Camelliae sinensis extract and polyvinyl alcohol (PVA) modification;

the addition amount of the wormwood/isatis root/tea extract in the porous molecular nest in the production process accounts for 1-5wt% of the total amount of the cellulose and polyvinyl alcohol raw materials, and the ratio of the addition amount of the polyvinyl alcohol (PVA) to the addition amount of the cellulose is 1: 9-1: 1.

further, the preparation of the Lyocell fiber comprises the following steps,

s1, preparing a plant extract;

s2, preparing a porous molecular nest;

s3, preparing a porous molecular nest PVA adhesive film;

s4, preparing the composite Lyocell fiber.

Further, in the step S1, the preparation of the plant extract comprises the following steps:

s11, preparing a wormwood extracting solution:

cleaning, drying and crushing the wormwood, and extracting by using a supercritical CO2 fluid extraction method under the conditions of extraction pressure of 30MPa, extraction temperature of 40 ℃ and extraction time of 100min, wherein the weight ratio of the wormwood: ethanol ═ 1: 2, adding entrainer ethanol in a mass ratio to obtain an extract. The extract is mainly wormwood essential oil with antibacterial and insect-proof effects.

S12, preparation of an isatis root alkaloid extract:

pulverizing radix Isatidis, reflux-extracting with 80% ethanol, filtering to obtain ethanol extract, concentrating the ethanol extract under reduced pressure, extracting with chloroform, collecting chloroform layer, heating under reduced pressure to recover chloroform, and oven drying the residual solid to obtain radix Isatidis extract. Wherein alkaloids with antibacterial and anti-inflammatory activities such as indigo blue and indirubin are used as main components, and the content of the alkaloids in the extract is about 90%;

s13, tea extract preparation:

vacuum drying and pulverizing dried green tea leaves, extracting with 50% ethanol at 60 deg.C, filtering to obtain filtrate, extracting with chloroform, collecting chloroform layer, evaporating under reduced pressure, and oven drying the residual solid to obtain tea extract. Wherein tea polyphenol and caffeine are used as main components.

In the steps, the key active components of the three raw materials are respectively extracted, and the content of tannic acid, amino acid and other impurities which are possibly combined with the effective components to interfere the subsequent process is reduced as much as possible.

Furthermore, the addition proportion of the wormwood extract, the isatis root alkaloid extract and the tea extract in the wormwood/isatis root/tea extract is 20-40%, 10-40% and 20-70%;

further, S2. preparation of the porous molecular nest, the process comprises:

s21, preparing a porous nano material dispersion liquid:

adding the porous nano material and absolute ethyl alcohol into a ball mill for grinding, shearing and dispersing to obtain a porous nano material dispersion liquid;

s22, preparation of a porous molecular nest containing plant extracts:

sequentially adding folium Artemisiae Argyi extract, radix Isatidis alkaloid extract, folium Camelliae sinensis extract, porous nanometer material dispersion, coupling agent, and surfactant into high-speed shearing disperser, and shearing;

the porous nano material is SiO2 microsphere, aerogel, montmorillonite, zeolite powder, TiO₂One or more of;

the coupling agent is a mixture of a silane coupling agent KH550 and a silane coupling agent KH570, and the mass ratio is 5 (1-3);

the surfactant is a mixture of Tween-80 and span-80, and the mass ratio is 10 (1-3);

the shearing process is specifically that the shearing force is 5250ips, the shearing time is 4min, the temperature is raised to 50 ℃ at the speed of 3 ℃/min, and the temperature is kept;

with the help of a coupling agent and a surfactant, molecules of the extract enter the porous nano microspheres through porous nano-pores and are encapsulated in the porous nano-microspheres to obtain a molecular nest dispersion liquid containing the green tea extract, and a solvent ethanol is evaporated under reduced pressure to obtain dry porous molecular nests containing the wormwood/isatis root/tea extract.

Further, S3, the preparation of the porous molecular nest PVA adhesive film comprises the following steps:

s31, dispersing porous molecular nests:

mixing PVA (polyvinyl alcohol with alcoholysis degree of more than 92%) powder with a predetermined amount and deionized water (the ratio of PVA to water is 5-12: 100), and keeping the mixture in a water bath kettle at 80 ℃ for 3 hours to obtain a PVA aqueous solution after the PVA aqueous solution is completely dissolved. Dispersing porous molecular nest containing plant extract into the solution, adding dispersant and surfactant, stirring, and ultrasonically dispersing to obtain film forming liquid.

The dispersing agent is selected from one of sodium polyacrylate, potassium polyacrylate and ammonium polyacrylate.

The surfactant comprises one or more of ionic surfactant (such as sodium dodecyl benzene sulfonate) and nonionic surfactant (such as alkylphenol and ethylene oxide condensate, alkylphenol polyoxyethylene, fatty alcohol and ethylene oxide condensate, and sorbitan fatty acid ester)

PVA with alcoholysis degree of more than 92 percent is not easy to dissolve at low temperature, so that the dissolving process of the PVA is convenient to control, and the dispersion of porous molecular nests is controlled. And a plurality of dispersing agents and surfactants are added to facilitate the dispersion of the porous molecular nest, and if subsequent plant molecules are dissolved out from the molecular nest in advance, the plant molecules can be uniformly dispersed in the spinning solution through the dispersing agents and the surfactants no matter the plant molecules are fat-soluble or water-soluble, so that the influence on the performance of the fabric is reduced.

S32. preparation of a PVA adhesive film:

pouring the film forming solution onto a large-area metal plate or glass plate, uniformly casting or blade-coating, and drying with hot air at 80 ℃ for 20-30 min to form a PVA film with the water content of 15-25%.

And S33, scraping the PVA film in a dry environment, and sealing and storing.

Further, S4. the preparation of the composite Lyocell fiber comprises the following steps:

s41, pretreatment of cellulose pulp: including but not limited to the procedures of crushing, activating enzyme, inactivating enzyme, filtering and drying cellulose pulp;

s42, mixing spinning stock solution: uniformly mixing pretreated cellulose pulp, a low-concentration NMMO (N-methylmorpholine-N-oxide) aqueous solution, a PVA adhesive film containing plant extract multi-molecular nests and an antioxidant at low temperature and normal pressure to fully swell the cellulose pulp and the PVA adhesive film, and avoiding local gelation of the outer layer of fibers in the dissolving process and obstruction of internal dissolution;

specifically, the concentration of NMMO in the low-concentration NMMO aqueous solution is 50-72 wt%, and the dosage of the NMMO aqueous solution is 150-200 times of the mass of the cellulose pulp; the low temperature is 40-70 ℃, and the cellulose cannot be dissolved in the aqueous solution of NMMO under the condition;

the antioxidant is propyl gallate, and the addition amount of the propyl gallate is 0.5-1 wt% of the NMMO content in the solution;

s43, stock solution dissolution:

heating, decompressing and dehydrating, and simultaneously ultrasonically dispersing to fully dissolve and uniformly disperse the cellulose pulp and the PVA film;

specifically, the temperature is increased to 90-95 ℃, the pressure is reduced to below 0.2MPa, and the water is dehydrated to the water content of 7-12 wt%;

s44, spinning:

filtering and defoaming the fully dissolved stock solution, and spinning in a spinning device to obtain Lyocell fiber containing the wormwood isatis root tea;

the specific spinning process conditions are as follows:

according to the invention, by utilizing the coating slow-release characteristic of the porous nano material and the characteristic that PVA can be dissolved in NMMO and can realize modification of Loycell fiber stock solution, natural active ingredients of wormwood, isatis root and tea with antibacterial, antiviral and antioxidant effects are compounded with the porous nano material and PVA and introduced into the fiber, so that the fiber has good antibacterial effect and biocompatibility, and is very suitable for special textile materials for medical treatment and health care.

Specifically, the scheme of the invention has the advantages that:

the key effective components of a plurality of natural plants such as wormwood essential oil, isatis root alkaloid, tea polyphenol, caffeine and the like are accurately collected, the bacteriostatic effect is improved as much as possible, and the influence of various impurities on the spinning process is reduced. Meanwhile, the introduction of tea polyphenol with reducibility can also be used as a protective agent to reduce the loss of other more effective antibacterial components when the tea polyphenol is contacted with NMMO.

Compared with a direct stock solution adding method, the coating slow-release characteristic of the porous nano material molecular nest is utilized, so that a certain isolation and buffering effect can be achieved before various active ingredients are directly contacted with an oxidizing solvent NMMO, and the inactivation loss and the side reaction of NMMO denaturation are reduced. On the basis, the molecular nests are pre-dispersed in the PVA gel and then dissolved in the stock solution, so that secondary encapsulation of the molecular nests is formed, the molecular nests gradually enter the stock solution along with the dissolution and diffusion of the PVA gel, and the contact chance of plant ingredients and NMMO in the dissolving and dispersing process is further reduced.

The coupling agent, the surfactant and the dispersing agent are fully added in the preparation of the molecular nest and the preparation of the PVA adhesive film, so that the molecular nest can be well dispersed in the pretreatment process, and good dispersing conditions are provided for the molecular nest and partial effective components released in advance in the dissolving process of the stock solution.

And the introduction of PVA can reduce the viscosity of the cellulose/NMMO/water solution, improve the preventability of the stock solution and further improve the quality of fiber products. After PVA (polyvinyl alcohol) is blended, the initial modulus and the breaking strength of the Lyocell fiber are greatly improved, and the reduction of the mechanical property of the fiber caused by introducing micromolecular plant components and inorganic nano materials is reduced. Meanwhile, experiments show that PVA modification also contributes to improvement of fibrillation of the Lyocell fibers. Finally, the strong water absorption of PVA also provides further advantages for some special medical and health care application occasions.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

the addition amount of the wormwood/isatis root/tea extract in the porous molecular nest in the production process accounts for 1.0 wt% of the total amount of the cellulose and polyvinyl alcohol raw materials, and the ratio of the addition amount of the polyvinyl alcohol (PVA) to the addition amount of the cellulose is 1: 9. assuming that the total amount of the plant extract is 1 part by mass, the amount of the PVA is 10 parts by mass and the amount of the cellulose is 90 parts by mass.

S1. preparation of plant extract

S11, preparing a wormwood extracting solution:

cleaning folium Artemisiae Argyi, vacuum drying for 2 hr, cutting into pieces (about 5 mesh), and treating with supercritical CO₂Extracting by a fluid extraction method under the conditions of extraction pressure of 30MPa, extraction temperature of 40 ℃, extraction time of 100min, and taking wormwood: ethanol ═ 1: 2, adding entrainer ethanol in a mass ratio to obtain an extract; the extract is mainly wormwood essential oil with antibacterial and insect-proof effects.

S12, preparation of an isatis root alkaloid extract:

pulverizing radix Isatidis into 40 mesh, extracting with 6 times of 80% ethanol under reflux for 4 hr, filtering to obtain ethanol extract, concentrating the ethanol extract under reduced pressure, extracting with chloroform, collecting chloroform layer, heating under reduced pressure to recover chloroform, and oven drying the residual solid at 60 deg.C to obtain radix Isatidis extract; wherein alkaloids with antibacterial activity such as indigo blue and indirubin are used as main components, and the content of the alkaloids in the extract is about 90%;

s13, tea extract preparation:

vacuum drying dried green tea leaves for 2h, pulverizing to 60 mesh, mixing at a ratio of 1: 15, extracting with 50% ethanol at 60 deg.C for 30min, filtering to obtain filtrate, extracting with chloroform, evaporating chloroform layer under reduced pressure, and oven drying at 60 deg.C to obtain tea extract mainly containing tea polyphenols and caffeine.

S2, preparing a porous molecular nest:

s21, preparing a porous nano material dispersion liquid:

mixing the porous nano material and absolute ethyl alcohol according to the weight ratio of 1: 10, adding the mixture into a ball mill for grinding, shearing and dispersing to obtain porous nano material dispersion liquid;

s22, preparation of a porous molecular nest containing plant extracts:

wherein the proportion of the wormwood extract, the isatis root alkaloid extract and the tea extract is 20%, 10% and 70%; namely, each weight part thereof was 0.2/0.1/0.7, respectively.

The porous nano material is SiO₂The total mass ratio of the microspheres to the plant extract is 6: 1. i.e. SiO₂The microspheres were taken in 6 parts by weight.

The coupling agent is a mixture of a silane coupling agent KH550 and a silane coupling agent KH570, the mass ratio is 5:2, and the dosage of the coupling agent is SiO₂8% of the mass of the microspheres;

the surfactant is a mixture of Tween-80 and span-80, the mass ratio is 10:2, and the dosage of the surfactant is SiO₂5 percent of the mass of the microspheres.

The total weight of the surfactant and the coupling agent is 0.78.

with the help of a coupling agent and a surfactant, molecules of the extract enter the porous nano microspheres through porous nano-pores and are encapsulated in the porous nano-microspheres to obtain a molecular nest dispersion liquid containing the green tea extract, and a solvent ethanol is evaporated under reduced pressure to obtain dry porous molecular nests containing the wormwood/isatis root/tea extract;

s3, preparing a porous molecular nest PVA adhesive film:

s31, dispersing porous molecular nests:

taking 10 and 100 parts by weight of PVA (polyvinyl alcohol with alcoholysis degree of more than 92%) powder and deionized water, and keeping the powder in a water bath kettle at 80 ℃ for 3 hours to completely dissolve the powder to obtain a product 1: 10 aqueous PVA solution. Dispersing porous molecular nest containing plant extract into solution, adding dispersant and surfactant with mass fraction of porous molecular nest of 2% (0.12 parts by mass), stirring, and ultrasonically dispersing for 30min to obtain membrane forming solution.

The dispersant is selected from one of sodium polyacrylate, potassium polyacrylate and ammonium polyacrylate, and the using amount is 0.6 part by mass.

The surfactant comprises sodium dodecyl benzene sulfonate and alkylphenol polyoxyethylene, and the dosage is 0.4 and 0.2 parts by mass respectively.

The PVA model is PVA 1799, and the alcoholysis degree is 99%.

S32. preparing a PVA film: pouring the film forming solution onto a large-area metal plate or glass plate, uniformly casting or blade-coating, and drying with hot air at 80 ℃ for 30min to form a PVA film with the water content of 15-25%.

And S33, scraping the PVA film in a dry environment, and sealing and storing.

S4, preparing the composite Lyocell fiber:

s41, pretreatment of cellulose pulp: crushing 90 parts by mass of lignocellulose pulp with alpha-cellulose mass fraction of about 88%, activating enzyme, inactivating enzyme, filtering and drying;

s42, mixing spinning stock solution: uniformly mixing pretreated cellulose pulp, 1800 parts by mass of low-concentration NMMO (N-methylmorpholine-N-oxide) aqueous solution, plant extract multi-molecular nest-containing PVA (polyvinyl acetate) adhesive film and an antioxidant at low temperature and normal pressure to fully swell the cellulose pulp and the PVA adhesive film, and avoiding local gelation of the outer layer of fibers and blockage of internal dissolution in the dissolving process;

specifically, the concentration of the NMMO in the low-concentration NMMO aqueous solution is 50 wt%, the low temperature is 40 ℃, and the cellulose cannot be dissolved in the aqueous solution of NMMO under the condition;

the antioxidant is propyl gallate, and the addition amount of the propyl gallate is 0.5 wt% of the NMMO content in the solution;

s43, stock solution dissolution:

specifically, the temperature is increased to 90 ℃, the pressure is reduced to below 0.2MPa, and dehydration is carried out until the water content is 10 wt%;

s44, spinning:

the specific spinning process conditions are as follows:

example 2

Compared with example 1, the ratio of folium Artemisiae Argyi extract, radix Isatidis alkaloid extract, and tea extract is 40%, and 20%, respectively, and the other conditions are not changed.

Example 3

Compared with example 2, the addition ratio of PVA to cellulose was changed to 1: 1, all other conditions were unchanged.

Example 4

Compared with example 2, the total amount of folium Artemisiae Argyi extract, radix Isatidis alkaloid extract, and tea extract is 5wt% of the total amount of cellulose and polyvinyl alcohol, and the other conditions are not changed.

Example 5

Compared with example 4, the addition ratio of PVA to cellulose was changed to 1: 1, all other conditions were unchanged. ,

comparative example 1

Compared with the example 5, two steps S2-S3 are eliminated, the porous nano material and PVA are not added, and the wormwood extracting solution, the isatis root alkaloid extract and the tea extract which are prepared by the S1 are directly added in the step S42, namely:

s41, pretreatment of cellulose pulp: 50 parts by mass of lignocellulose pulp with alpha-cellulose mass fraction of about 88 percent is crushed, enzyme is activated, enzyme is deactivated, filtered and dried;

s42, mixing spinning stock solution: the cellulose pulp after pretreatment, 1000 parts by mass of a low-concentration NMMO (N-methylmorpholine-N-oxide) aqueous solution and an antioxidant are uniformly mixed at low temperature and normal pressure, so that the cellulose pulp is fully swelled.

the antioxidant is propyl gallate, and the addition amount of the propyl gallate is 0.5 wt% of NMMO;

s43, stock solution dissolution:

heating, decompressing and dehydrating, and simultaneously performing ultrasonic dispersion to fully dissolve and uniformly disperse the cellulose pulp and the plant extract;

s44, spinning:

and filtering and defoaming the fully dissolved stock solution, and feeding the fully dissolved stock solution into spinning equipment for spinning.

Comparative example 2

Compared with the example 5, the step of S3 is eliminated, namely the porous molecular nest prepared in the step of S2 is directly put into the spinning solution in the step of S42, and the rest is the same as the comparative example 1.

Test example 1

The Lyocell fibers prepared in examples 1 to 5 and comparative examples 1 to 2 were processed through a Lyocell fiber weaving line to prepare a Lyocell fabric, and then evaluated in GB/T20944.2-2007 "evaluation of antibacterial properties of textiles section 2: the antibacterial property test of each Lyocell fabric by the absorption method is expressed by the inhibition rate of staphylococcus aureus and the inhibition rate of escherichia coli, and the test results are shown in table 1:

TABLE 1

Test example 2

The mechanical properties of the fibers were measured with an XQ-1 type monofilament Strength apparatus. The Lyocell fiber had a holding length of 20mm and a drawing rate of 5 mm/min. The measurements were repeated 20 times for each fiber sample and the results averaged. The results are shown in Table 2.

TABLE 2

From the test example 1, it can be seen that the wormwood/isatis root/tea composite extract in the present invention has excellent bacteriostatic effect, but from the comparative example, if plant components are directly added, the bacteriostatic activity is significantly affected. The porous molecular nest and PVA modification can effectively protect the bacteriostatic effect of the effective components of plants, and the two can cooperate to ensure that the requirement of bacteriostatic products is met.

It can be known from test example 2 that both the plant components and the porous molecular nest influence the mechanical properties of the fibers, and the mechanical properties of the fibers can be ensured and even further improved by properly combining the PVA modification.

Therefore, the natural effective components of the wormwood, the isatis root and the tea introduced into the Loycell fiber are reasonable and efficient, and the antibacterial effect and the mechanical property can be skillfully considered by utilizing the coating slow-release characteristic of the porous nano material and the design that PVA can be dissolved in NMMO and modifies the stock solution of the Loycell fiber, so that the design function of the fiber can be relatively ideally realized, and the fiber can be popularized in special textile materials for medical treatment and health care.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A Lyocell fiber containing folium Artemisiae Argyi/radix Isatidis/folium Camelliae sinensis and its preparation method are characterized by comprising porous molecular nest containing folium Artemisiae Argyi/radix Isatidis/folium Camelliae sinensis extract and polyvinyl alcohol (PVA) modification;

2. the Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 1, wherein the preparation of the Lyocell fiber comprises the following steps:

s1, preparing a plant extract;

s2, preparing a porous molecular nest;

s3, preparing a porous molecular nest PVA adhesive film;

s4, preparing the composite Lyocell fiber.

3. The Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 2, wherein said s1. preparation of plant extract comprises:

s11, preparing a wormwood extracting solution:

S12, preparation of an isatis root alkaloid extract:

pulverizing radix Isatidis, reflux-extracting with 80% ethanol, filtering to obtain ethanol extract, concentrating the ethanol extract under reduced pressure, extracting with chloroform, collecting chloroform layer, heating under reduced pressure to recover chloroform, and oven drying the residual solid to obtain radix Isatidis extract. Wherein alkaloids with antibacterial and antiviral activities such as indigo blue and indirubin are used as main components, and the content of the alkaloids in the extract is about 90%;

s13, tea extract preparation:

4. The Lyocell fiber containing wormwood/radix isatidis/tea and the preparation method thereof as claimed in claim 3, wherein the addition ratio of wormwood extract, radix isatidis alkaloid extract and tea extract in the wormwood/radix isatidis/tea extract is 20% -40%, 10% -40% and 20% -70%.

5. The Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 2, wherein said s2. preparation of porous molecular nest, the process comprises:

s21, preparing a porous nano material dispersion liquid:

s22, preparation of a porous molecular nest containing plant extracts:

evaporating the solvent ethanol under reduced pressure to obtain dried porous molecular nest containing folium Artemisiae Argyi/radix Isatidis/tea extract.

6. The Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 2, wherein said s3. preparation of porous molecular nest PVA glue film comprises the following steps:

s31, dispersing porous molecular nests:

mixing PVA powder and deionized water, heating and dissolving completely to obtain PVA water solution. Dispersing porous molecular nest containing plant extract into the solution, adding dispersant and surfactant, stirring, and ultrasonically dispersing to obtain film forming liquid;

the surfactant comprises an ionic surfactant and a nonionic surfactant at the same time;

s32. preparation of a PVA adhesive film:

pouring the film forming solution onto a large-area metal plate or glass plate, uniformly casting or blade-coating, and drying by hot air at 80 ℃ to form a PVA film with low water content;

and S33, scraping the PVA film in a dry environment, and sealing and storing.

7. The Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 2, wherein said s4. preparation of composite Lyocell fiber comprises the following steps:

s41, pretreatment of cellulose pulp, including crushing, enzyme activation, filtration and drying;

s42, mixing spinning stock solution: uniformly mixing pretreated cellulose pulp, a low-concentration NMMO (N-methylmorpholine-N-oxide) aqueous solution, a PVA adhesive film containing plant extract multi-molecular nests and an antioxidant at low temperature and normal pressure to fully swell the cellulose pulp and the PVA adhesive film;

s43, stock solution dissolution:

s44, spinning:

and (3) filtering and defoaming the fully dissolved stock solution, and spinning in a spinning device to obtain the Lyocell fiber containing the wormwood, the isatis root and the tea.

8. The Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 7, wherein the low concentration aqueous solution of NMMO in S42 has a NMMO concentration of 50-72 wt%; the low temperature and normal pressure is 40-70 ℃, and the ambient atmospheric pressure is adopted; and (S43) heating and decompressing for dehydration under the conditions that the temperature is increased to 90-95 ℃, the pressure is reduced to below 0.2MPa, and the dehydration is carried out until the water content is 7-12 wt%.

9. The Lyocell fiber containing wormwood/isatis root/tea and the preparation method thereof as claimed in claim 6, wherein the PVC powder has a structural characteristic of alcoholysis degree of 92% or more.

10. The Lyocell fiber containing wormwood/isatis root/tea as claimed in claim 6, wherein the dispersant is selected from one of sodium polyacrylate, potassium polyacrylate and ammonium polyacrylate, the ionic surfactant is sodium dodecylbenzene sulfonate, the non-ionic surfactant is one or more of phenol-ethylene oxide condensate, alkylphenol ethoxylate, fatty alcohol-ethylene oxide condensate and sorbitan fatty acid ester.