A negative oxygen ion air purification material and its preparation process

Abstract

The present invention provides a negative oxygen ion air purification material and its preparation process, which relates to the field of textile fibers. The process includes the following steps: mixing nano-tourmaline powder with an aqueous solution of graphene oxide, and performing ultrasonic dispersion; adding urea to a cellulose solution, stirring evenly, and then adding epichlorohydrin, and stirring for 1 - 2 h; then adding mixture A and a water-soluble polyethylene glycol solution simultaneously, and stirring for 1 - 2 h to obtain a spinning solution; performing spinning to form fiber filaments; adding nano-tourmaline powder to an aqueous ethanol solution, then adding a double-bond silane coupling agent and β-cyclodextrin, and then adding a starch aqueous solution to obtain mixture B; placing the fiber filaments in mixture B, standing at 1 - 2 °C for 15 - 18 h, and drying under low-temperature vacuum to obtain modified fiber filaments; using the modified fiber filaments as the core material and plant fibers as the outer fiber layer to spin a core-spun yarn; soaking the core-spun yarn in water multiple times and drying it naturally. The nano-tourmaline powder in this material is not easy to fall off, has a strong bonding fastness with the fibers, and has strong wash resistance.

Description

Technical Field

[0001] The present invention relates to the field of textile fibers, and in particular, to a negative oxygen ion air purification material and a preparation process thereof. Background Art

[0002] Negative oxygen ions refer to the general term of single gas molecules and hydrogen ion groups with negative charges. Negative oxygen ions have the effect of purifying air, can decompose pollutants such as formaldehyde and toluene in the air, and can combine with bacteria to change the structure of bacteria, achieving the effect of sterilization.

[0003] Introducing negative oxygen ions into fabrics can release a certain amount of negative oxygen ions into the surrounding environment, thereby achieving the effect of purifying air. Currently, there are mainly two ways to add negative oxygen ions to fabrics. One is to directly apply, soak, wrap, etc. on the surface of fibers or fabrics, so that negative oxygen ion generating substances (such as tourmaline powder, etc.) are loaded on the surface of fibers or fabrics. After making the fibers or fabrics into products, they can release negative oxygen ions. The other is to mix negative oxygen ion generating substances with fiber raw materials during the preparation of fibers, and then make fiber filaments through processes such as spinning, so that the fibers or fabrics can release negative oxygen ions.

[0004] Patent 202210831552.1 discloses a negative ion heating graphene modified fine denier fiber and a preparation method thereof. It uses graphene oxide to modify cotton linter fibers to obtain fiber blanks, and then disperses and mixes the fiber blanks with tourmaline slurry. After operations such as washing and oiling, fibers that can release negative oxygen ions can be obtained.

[0005] Patent 202210425846.4 discloses a fabric containing negative oxygen ions and a production process thereof. It adds negative ion powder to the fabric treatment agent, and then uses this treatment agent to treat the fabric to obtain a fabric that can release negative oxygen ions.

[0006] Patent 202011590445.1 discloses a method for making fibers that generate negative ions. It mixes a mixed powder of tourmaline, zeolite, titanium dioxide, and alumina with organic solvents, coupling agents, dispersants, etc., and then performs co-blending granulation and wet spinning to obtain negative oxygen ion fibers.

[0007] For currently disclosed fibers or fabrics that can release negative oxygen ions, the binding fastness between tourmaline and the fibers / fabrics is low, and it is easy to fall off after washing, and cannot release negative oxygen ions for a long time. Summary of the Invention

[0008] The object of the present invention is to provide a negative oxygen ion air purification material. Part of the nano-tourmaline powder is adhered inside the inner layer fiber, and part of the nano-tourmaline powder is on the surface of the fiber. The nano-tourmaline powder is not easy to fall off, and the bonding fastness with the fiber is strong.

[0009] Another object of the present invention is to provide a preparation method of a negative oxygen ion air purification material. The core-spun yarn fiber prepared by this method can release negative oxygen ions for a long time.

[0010] The present invention solves its technical problems by adopting the following technical solutions.

[0011] On the one hand, an embodiment of the present invention provides a preparation process of a negative oxygen ion air purification material, including the following steps:

[0012] S1: Mix nano-tourmaline powder with an aqueous solution of graphene oxide, and disperse it by ultrasonic wave to obtain mixture A; add urea to the cellulose solution, stir evenly, then add epichlorohydrin, and stir for 1-2 h; then add the above mixture A and a water-soluble polyethylene glycol solution at the same time, and stir for 1-2 h to obtain a spinning solution; spin the spinning solution to form a fiber filament;

[0013] S2: Add nano-tourmaline powder to an aqueous ethanol solution, after ultrasonic dispersion, add a double-bond silane coupling agent and β-cyclodextrin, stir evenly, then add a starch aqueous solution, and disperse it evenly by ultrasonic wave to obtain mixture B; place the fiber filament prepared in step S2 in the mixture B, let it stand at 1-2 °C for 15-18 h, and dry it by low-temperature vacuum drying to obtain a modified fiber filament;

[0014] S3: Use the modified fiber filament prepared in step S2 as the core material, and plant fiber as the outer fiber layer to spin a core-spun yarn;

[0015] S4: Soak the core-spun yarn in water for multiple times and dry it naturally.

[0016] Using the modified fiber loaded with nano-tourmaline powder as the core material and plant fiber as the outer layer, spin a core-spun yarn. After washing with water, remove part of the starch on the surface of the inner layer fiber, so that there are certain pores between the inner layer and the outer layer. On the one hand, it can increase the hygroscopicity and adsorption of the fiber, and the pores can be used to adsorb pollutants in the air. On the other hand, substances such as tourmaline powder falling off from the inner layer fiber can be restricted in the pores, and the probability of separation of tourmaline powder from the fiber can also be reduced.

[0017] In some embodiments of the present invention, the cellulose solution is prepared by the following steps: Crush bamboo fiber, then soak it in a sodium hydroxide solution, heat it to 45-55 °C, and add carbon disulfide to the reaction system at this temperature, stir evenly, and keep it warm for 5-6 h to obtain the cellulose solution.

[0018] In some embodiments of the present invention, it further includes: during the heat preservation process, an inert gas is introduced into the reaction system through an aeration device. During the preparation of the cellulose solution, through aeration treatment, the fibers can be made more fluffy, and micropores can be formed on the fibers, providing space for the subsequent loading of tourmaline powder, and making the binding between cyclodextrin molecules and fiber filaments closer.

[0019] In some embodiments of the present invention, the above-mentioned double-bond silane coupling agent is γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane or vinyltrimethoxysilane. The double-bond coupling agent can provide double-bond functional groups and can act as a dispersant during the reaction to avoid the agglomeration of nano-tourmaline powder.

[0020] In some embodiments of the present invention, in step S2, it further includes adding an antibacterial agent to the mixture B;

[0021] Among them, the antibacterial agent includes the following raw materials by weight: 10-20 parts of chitosan quaternary ammonium salt, 5-10 parts of titanium dioxide, and 0.5-1 part of potassium persulfate.

[0022] Adding the antibacterial agent in step S2, the chitosan quaternary ammonium salt in the antibacterial agent has certain antibacterial properties, titanium dioxide can absorb ultraviolet light and extend the antibacterial time of the quaternary ammonium salt; and the double-bond silane coupling agent can graft and modify titanium dioxide, making titanium dioxide have reactive double-bond groups, which can be combined on the fiber through reaction. Secondly, during the ultrasonic dispersion process of chitosan quaternary ammonium salt, the molecular chain can wind around the fiber, thereby improving the loading fastness.

[0023] In some embodiments of the present invention, the plant fiber is one or more of cotton fiber, bamboo fiber, ramie fiber and sisal fiber.

[0024] In some embodiments of the present invention, in the step S2, the mass ratio of nano-tourmaline powder, double-bond silane coupling agent and β-cyclodextrin is 1:(0.1-0.5):(1.5-3). Adding a small amount of silane coupling agent can disperse the nano-tourmaline powder and act as a bridge between inorganic and organic molecules, making it easier for cyclodextrin to coat the nano-tourmaline powder. Adding an excessive amount of cyclodextrin can ensure that most of the nano-tourmaline powder is coated, and the excessive cyclodextrin can also increase the viscosity of the solution system, making the coating easier to load on the fiber filaments.

[0025] In some embodiments of the present invention, in the step S1, the mass ratio of the nano-tourmaline powder to the water-soluble polyethylene glycol is 1:(0.5-1). Adding a small amount of polyethylene glycol can increase the number of hydroxyl groups on the fiber filaments, that is, hydroxylate the fiber filaments. The hydroxyl groups can form hydrogen bonds with stronger molecular forces with substances such as cyclodextrin, thereby improving the binding strength.

[0026] In some embodiments of the present invention, in the step S2, the mass ratio of nano-tourmaline powder to starch is 1:(2 - 5).

[0027] On the other hand, an embodiment of the present invention provides a negative oxygen ion air purification material prepared by the above preparation process.

[0028] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects:

[0029] In the present application, nano-tourmaline powder is loaded on the fiber in different ways. Since tourmaline can release negative ions, and negative ions in the air can play a role in purifying the air, the fabric made of the fiber of the present application, such as curtains, etc., can continuously release negative ions to achieve the effect of purifying indoor air.

[0030] In the present application, nano-tourmaline powder is modified by graphene oxide and then mixed with cellulose solution. Together with water-soluble polyethylene glycol, the fiber filaments obtained after spinning and forming have a cross-linked network structure formed by polyethylene glycol, graphene oxide, and cellulose, and the nano-tourmaline powder is embedded in the network structure. On the one hand, it can enhance the fastness between the tourmaline powder and the matrix. On the other hand, the cross-linking and entanglement of graphene molecules and cellulose molecules can enhance the elasticity and strength of the fiber. Secondly, the hydroxyl groups of polyethylene glycol in the fiber filaments can serve as active sites for subsequent reactions.

[0031] On the other hand, a double-bond silane coupling agent and β-cyclodextrin are added to the nano-tourmaline powder. Using the encapsulation property of β-cyclodextrin, the nano-tourmaline powder is encapsulated inside, and the double-bond silane coupling agent can also play a dispersing role. During the reaction process, the agglomeration of nano-tourmaline powder can be avoided, and the formation of smaller particle size encapsulated products can be promoted; using the adhesion of starch, it makes it easier for cyclodextrin and the double-bond silane coupling agent to adhere to the fiber filaments. During the low-temperature soaking process, cyclodextrin can form hydrogen bonds with the hydroxyl groups on the fiber filaments, so that cyclodextrin can in-situ encapsulate the nano-tourmaline powder on the fiber filaments, improving the firmness between the nano-tourmaline powder and the fiber filaments.

[0032] In summary, through two loadings of nano-tourmaline powder, the present invention can, on the one hand, increase the loading amount of nano-tourmaline powder, and on the other hand, increase the loading strength, making the fabric more wash-resistant, the tourmaline powder stay on the fabric for a longer time, and the fabric release negative oxygen ions for a longer time. Detailed implementation manners

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely below. For those not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. Reagents or instruments without indicating the manufacturer can be obtained as conventional products through commercial purchase.

[0034] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to specific embodiments.

[0035] Example 1

[0036] S1: Crush bamboo fibers to 1 - 2 cm, then soak them in a sodium hydroxide solution with a mass fraction of 2% for 30 min. Subsequently, raise the temperature of the system to 55°C, and at this temperature, add carbon disulfide liquid to the reaction system, stir evenly, and keep warm for 6 h. During the heat preservation process, introduce nitrogen into the reaction system through an aeration device to obtain the cellulose solution; mix nano - tourmaline powder with an aqueous solution of graphene oxide, and disperse it by ultrasonic wave to obtain mixture A; add urea to the cellulose solution, stir evenly, then add epichlorohydrin, and stir for 2 h; then add the above - mentioned mixture A and a water - soluble polyethylene glycol solution simultaneously, and stir for 2 h to obtain a spinning solution; filter and degas the spinning solution, and add it to a spinning bath at 40°C for spinning and forming to obtain fiber filaments; where the spinning bath includes: 80 g / L sulfuric acid, 150 g / L sodium sulfate, and 5 g / L zinc sulfate; the mass ratio of the nano - tourmaline powder to the water - soluble polyethylene glycol is 1:0.5; the mass ratio of the nano - tourmaline powder to graphene oxide is 1:1, and the addition amounts of carbon disulfide, urea, and epoxyhexane are all 1% of the mass of the bamboo fibers.

[0037] S2: Add nano - tourmaline powder to an ethanol - water solution, disperse it by ultrasonic wave, then add γ - methacryloyloxypropyltrimethoxysilane and β - cyclodextrin, stir evenly, and then add a starch aqueous solution, and disperse it evenly by ultrasonic wave to obtain mixture B; place the fiber filaments prepared in step S2 in mixture B, soak them statically at 2°C for 18 h, and dry them by low - temperature vacuum drying to obtain modified fiber filaments; where the mass ratio of the nano - tourmaline powder, the double - bond silane coupling agent, and β - cyclodextrin is 1:0.1:1.5; the mass ratio of the nano - tourmaline powder to starch is 1:3;

[0038] S3: Use the modified fiber filaments prepared in step S2 as the core material, and use cotton fibers as the outer fiber layer to spin a core - spun yarn;

[0039] S4: Soak the core - spun yarn in water 3 times, soak it for 20 min each time, and then dry it naturally.

[0040] Example 2

[0041] S1: Crush the bamboo fiber to 1 - 2 cm, then soak it in a sodium hydroxide solution with a mass fraction of 4% for 30 min. Subsequently, raise the temperature of the system to 45°C, and at this temperature, add carbon disulfide liquid to the reaction system, stir evenly, and keep warm for 6 h. During the heat preservation process, introduce nitrogen into the reaction system through an aeration device to obtain the cellulose solution; mix nano - tourmaline powder with an aqueous solution of graphene oxide, and disperse it by ultrasonic wave to obtain mixture A; add urea to the cellulose solution, stir evenly, then add epichlorohydrin, and stir for 1.5 h; then add the above - mentioned mixture A and a water - soluble polyethylene glycol solution simultaneously, and stir for 2 h to obtain a spinning solution; filter and defoam the spinning solution, and add it to a spinning bath at 45°C for spinning and forming to obtain fiber filaments; wherein the spinning bath includes: 80 g / L sulfuric acid, 150 g / L sodium sulfate, and 5 g / L zinc sulfate; the mass ratio of the nano - tourmaline powder to the water - soluble polyethylene glycol is 1:1; the mass ratio of the nano - tourmaline powder to the graphene oxide is 1:1, and the addition amounts of carbon disulfide, urea, and epoxyhexane are all 1% of the mass of the bamboo fiber.

[0042] S2: Add nano - tourmaline powder to an ethanol - water solution, disperse it by ultrasonic wave, then add γ - methacryloyloxypropyltrimethoxysilane and β - cyclodextrin, stir evenly, and then add a starch aqueous solution, and disperse it evenly by ultrasonic wave to obtain mixture B; place the fiber filaments prepared in step S2 in mixture B, soak them statically at 2°C for 18 h, and dry them by low - temperature vacuum drying to obtain modified fiber filaments; wherein, the mass ratio of the nano - tourmaline powder, the double - bond silane coupling agent, and β - cyclodextrin is 1:0.2:2; the mass ratio of the nano - tourmaline powder to the starch is 1:3;

[0043] S3: Use the modified fiber filaments prepared in step S2 as the core material, and use cotton fiber as the outer fiber layer to spin a core - spun yarn;

[0044] S4: Soak the core - spun yarn in water 3 times, soak it for 20 min each time, and then dry it naturally.

[0045] Example 3

[0046] S1: Pulverize bamboo fibers to 1 - 2 cm, then soak them in a sodium hydroxide solution with a mass fraction of 2% for 30 min. Subsequently, raise the temperature of the system to 55 °C, and at this temperature, add carbon disulfide liquid to the reaction system, stir evenly, and keep warm for 5 h. During the heat preservation process, introduce nitrogen into the reaction system through an aeration device to obtain the cellulose solution; mix nano - tourmaline powder with an aqueous solution of graphene oxide, and disperse it by ultrasonic wave to obtain mixture A; add urea to the cellulose solution, stir evenly, then add epichlorohydrin and stir for 2 h; then add the above - mentioned mixture A and an aqueous solution of water - soluble polyethylene glycol simultaneously and stir for 2 h to obtain a spinning solution; filter and degas the spinning solution, and add it to a spinning bath at 40 °C for spinning and forming to obtain fiber filaments; where the spinning bath includes: sulfuric acid 80 g / L, sodium sulfate 150 g / L, zinc sulfate 5 g / L; the mass ratio of the nano - tourmaline powder to the water - soluble polyethylene glycol is 1:0.8; the mass ratio of the nano - tourmaline powder to the graphene oxide is 1:1.5, and the addition amounts of carbon disulfide, urea, and epoxyhexane are all 1% of the mass of the bamboo fibers.

[0047] S2: Add nano - tourmaline powder to an aqueous ethanol solution, disperse it by ultrasonic wave, then add γ - methacryloyloxypropyltrimethoxysilane and β - cyclodextrin, stir evenly, and then add an aqueous starch solution and disperse it evenly by ultrasonic wave to obtain mixture B; place the fiber filaments prepared in step S2 in mixture B, soak them statically at 1 °C for 18 h, and dry them under low - temperature vacuum to obtain modified fiber filaments; where the mass ratio of the nano - tourmaline powder, the double - bond silane coupling agent, and β - cyclodextrin is 1:0.5:1.5; the mass ratio of the nano - tourmaline powder to the starch is 1:3;

[0048] S3: Use the modified fiber filaments prepared in step S2 as the core material and ramie fibers as the outer fiber layer to spin a core - spun yarn;

[0049] S4: Soak the core - spun yarn in water 3 times, soak it for 20 min each time, and then dry it naturally.

[0050] Example 4

[0051] S1: Crush the bamboo fiber to 1 - 2 cm, then soak it in a sodium hydroxide solution with a mass fraction of 2% for 30 min. Subsequently, raise the temperature of the system to 55 °C, and at this temperature, add carbon disulfide liquid to the reaction system, stir evenly, and keep warm for 6 h. During the heat preservation process, introduce nitrogen into the reaction system through an aeration device to obtain the cellulose solution; mix nano - tourmaline powder with an aqueous solution of graphene oxide, and disperse it by ultrasonic wave to obtain mixture A; add urea to the cellulose solution, stir evenly, then add epichlorohydrin, and stir for 2 h; then add the above - mentioned mixture A and an aqueous solution of water - soluble polyethylene glycol simultaneously, and stir for 2 h to obtain a spinning solution; filter and defoam the spinning solution, and add it to a spinning bath at 40 °C for spinning and forming to obtain fiber filaments; where the spinning bath includes: 80 g / L sulfuric acid, 150 g / L sodium sulfate, and 5 g / L zinc sulfate; the mass ratio of the nano - tourmaline powder to the water - soluble polyethylene glycol is 1:0.5; the mass ratio of the nano - tourmaline powder to the graphene oxide is 1:1, and the addition amounts of carbon disulfide, urea, and epoxyhexane are all 1% of the mass of the bamboo fiber.

[0052] S2: Add nano - tourmaline powder to an ethanol - water solution, disperse it by ultrasonic wave, then add γ - methacryloyloxypropyltrimethoxysilane and β - cyclodextrin, stir evenly, and then add an aqueous starch solution, and disperse it evenly by ultrasonic wave to obtain mixture B; add an antibacterial agent to mixture B. The antibacterial agent includes the following raw materials by weight: 10 parts of chitosan quaternary ammonium salt, 5 parts of titanium dioxide, and 1 part of potassium persulfate. Place the fiber filaments prepared in step S2 in mixture B containing the antibacterial agent, stir at 60 °C for 4 h, then cool down to 2 °C, and soak and stand at this temperature for 18 h, and then dry it under low - temperature vacuum to obtain modified fiber filaments; where the mass ratio of the nano - tourmaline powder, the double - bond silane coupling agent, and β - cyclodextrin is 1:0.1:1.5; the mass ratio of the nano - tourmaline powder to the starch is 1:3, and the addition mass of the antibacterial agent is 5% of the dry weight of the fiber filaments;

[0053] S3: Use the modified fiber filaments prepared in step S2 as the core material and bamboo fiber as the outer fiber layer to spin a core - spun yarn;

[0054] S4: Soak the core - spun yarn in water 3 times, soak for 20 min each time, and then dry it naturally.

[0055] Example 5

[0056] The difference from Example 1 is that in this example, the mass ratio of the nano - tourmaline powder, the double - bond silane coupling agent, and β - cyclodextrin is 1:0.5:3; the rest is the same as Example 1.

[0057] Example 6

[0058] It is different from Example 1 in that in this example, the mass ratio of nano-tourmaline powder, double-bond silane coupling agent and β-cyclodextrin is 1:0.1:3; the rest is the same as in Example 1.

[0059] Example 7

[0060] It is different from Example 1 in that in this example, the mass ratio of nano-tourmaline powder to starch is 1:2; the rest is the same as in Example 1.

[0061] Example 8

[0062] It is different from Example 1 in that in this example, the mass ratio of nano-tourmaline powder to starch is 1:5; the rest is the same as in Example 1.

[0063] Example 9

[0064] It is different from Example 1 in that in this example, the silane coupling agent is vinyltriethoxysilane; the rest is the same as in Example 1.

[0065] Example 10

[0066] It is different from Example 1 in that in this example, the silane coupling agent is vinyltrimethoxysilane; the rest is the same as in Example 1.

[0067] Example 11

[0068] It is different from Example 4 in that in this example, the antibacterial agent comprises the following raw materials by weight: 20 parts of chitosan quaternary ammonium salt, 10 parts of titanium dioxide and 1 part of potassium persulfate; the rest is the same as in Example 4.

[0069] Example 12

[0070] It is different from Example 4 in that in this example, the antibacterial agent comprises the following raw materials by weight: 15 parts of chitosan quaternary ammonium salt, 5 parts of titanium dioxide and 0.5 part of potassium persulfate; the rest is the same as in Example 4.

[0071] Comparative Example 1

[0072] It is different from Example 1 in that in step S2 of this comparative example, no silane coupling agent and β-cyclodextrin are added, and the rest is the same as in Example 1.

[0073] Comparative Example 2

[0074] It is different from Example 1 in that in step S2 of this comparative example, no starch aqueous solution is added, and the same amount of water is directly added, and the rest is the same as in Example 1.

[0075] Comparative Example 3

[0076] The difference from Example 4 is that in step S2 of this comparative example, no silane coupling agent and starch are added, and the rest is the same as in Example 4.

[0077] Experimental Example

[0078] The fibers of Examples 1-12 and Comparative Examples 1-3 were respectively woven into layer fabrics through the textile process, and several cloth pieces of the same size were cut out for standby.

[0079] 1. Measurement of the negative ion generation amount of the fabric

[0080] Using "GB / T 30128-2013 Testing and Evaluation of Negative Ion Generation Amount of Textiles", the negative ion generation amounts before washing, after 1 wash, after 10 washes, after 20 washes, and after 50 washes were respectively tested, and the results are shown in Table 1. It should be noted that the washing refers to placing the fabric in deionized water, soaking for 10 min, kneading 10 times, soaking for another 10 min, and then taking it out and drying it naturally. Among them, the value of each item in Table 1 is the average value of the negative ion generation amounts of 3 cloth pieces.

[0081] Table 1 Negative ion generation amount of the fabric (pieces / cm 3 )

[0082] Before water washing After 1 water wash After 10 water washes After 20 water washes After 50 water washes Example 1 1584 1526 1423 1221 985 Example 2 1523 1501 1452 1214 1015 Example 3 1563 1522 1421 1189 987 Example 4 1549 1509 1411 1175 1011 Example 5 1535 1489 1421 1201 992 Example 6 1426 1403 1345 1153 1001 Example 7 1526 1488 1406 1179 897 Example 8 1589 1511 1475 1203 1021 Example 9 1475 1423 1369 1147 951 Example 10 1533 1478 1401 1158 963 Example 11 1584 1514 1475 1143 976 Example 12 1563 1508 1426 1154 984 Comparative Example 1 1024 874 654 312 112 Comparative Example 2 1102 1011 845 640 401 Comparative Example 3 1032 984 723 511 321

[0083] From the data in Table 1 above, it can be concluded that for the fabrics of Examples 1-12, as the number of washing times increases, the negative ion generation amount decreases. This is because during the washing and kneading process, a small amount of tourmaline will inevitably fall off. After the number of tourmaline decreases, the corresponding negative ion generation amount will also decrease. However, for the fabrics of Examples 1-12, after 20 washes, there is still a relatively high generation amount, and after 50 washes, the generation amount is also relatively high. But for the fabrics of Comparative Examples 1-3, after 50 washes, the negative ion generation amount decreases significantly, indicating that a large amount of tourmaline falls off during the washing process. The reason is that in Comparative Example 1, no coupling agent and cyclodextrin are added, and the tourmaline added in step S2 cannot be wrapped, and its binding strength with the inner layer fiber filaments is low. After multiple washes, a large amount of tourmaline in this part falls off, resulting in a sharp decrease in the negative ion generation amount. In Comparative Example 2, no starch is added, that is, the gap between the inner layer fiber and the outer layer fiber is small, and more tourmaline falls off than in the examples, and the negative ion generation amount also decreases accordingly.

[0084] 2. Antibacterial property test

[0085] The antibacterial performance was tested according to GB / T20944.3-2008, using Escherichia coli (ATCC25922) specifically, and measured by the antibacterial rate. The antibacterial rate was the average value of 3 pieces of fabric, and the results are shown in Table 2.

[0086] Table 2 Antibacterial rate (%)

[0087] Before water washing After 1 water wash After 10 water washes After 20 water washes After 50 water washes Example 4 98.2 97.6 95.4 92.3 90.2 Example 11 97.3 95.8 94.3 91.1 89.5 Example 12 97.5 95.3 91.2 89.1 88.5 Comparative Example 3 96.3 90.2 75.3 54.1 36.2

[0088] It can be seen from Table 2 that the fabrics of Examples 4, 11 and 12 have excellent antibacterial properties. After multiple washes, the antibacterial property can still reach about 90%. However, for Comparative Example 3, during the preparation of the fiber filaments, no silane coupling agent was added, resulting in low binding strength between the chitosan quaternary ammonium salt and the fiber. After multiple washes, the antibacterial agent would fall off, leading to a decrease in the antibacterial effect.

[0089] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the present invention claimed, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

Claims

1. A preparation process of a negative oxygen ion air purification material, characterized in that, It includes the following steps: S1: Mix nano tourmaline powder with an aqueous solution of graphene oxide, and disperse it by ultrasonic treatment to obtain mixture A; add urea to the cellulose solution, stir evenly, then add epichlorohydrin, and stir for 1 - 2 h; then add the above-mentioned mixture A and a water-soluble polyethylene glycol solution simultaneously, and stir for 1 - 2 h to obtain a spinning solution; carry out spinning molding on the spinning solution to obtain fiber filaments; S2: Add nano tourmaline powder to an aqueous ethanol solution, after ultrasonic dispersion, add a double-bond silane coupling agent and β-cyclodextrin, stir evenly, then add a starch aqueous solution, and disperse it evenly by ultrasonic treatment to obtain mixture B; place the fiber filaments prepared in step S2 in the mixture B, let it stand at 1 - 2 °C for 15 - 18 h, and carry out low-temperature vacuum drying to obtain modified fiber filaments; S3: Use the modified fiber filaments prepared in step S2 as the core material, and use plant fiber as the outer fiber layer to spin and obtain a core-spun yarn; S4: Soak the core-spun yarn in water for multiple times and dry it naturally; Among them, the cellulose solution is prepared by the following steps: Crush bamboo fiber, then soak it in a sodium hydroxide solution, heat it up to 45 - 55 °C, and at this temperature, add carbon disulfide to the reaction system, stir evenly, keep it warm for 5 - 6 h, and introduce an inert gas into the reaction system through an aeration device; obtain the cellulose solution.

2. The preparation process of the negative oxygen ion air purification material according to claim 1, characterized in that, The double-bond silane coupling agent is γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane or vinyltrimethoxysilane.

3. The preparation process of the negative oxygen ion air purification material according to claim 1, characterized in that, In step S2, it also includes adding an antibacterial agent to mixture B; Among them, the antibacterial agent includes the following raw materials by weight parts: 10 - 20 parts of chitosan quaternary ammonium salt, 5 - 10 parts of titanium dioxide, and 0.5 - 1 part of potassium persulfate.

4. The preparation process of the negative oxygen ion air purification material according to claim 1, characterized in that, The plant fiber is one or more of cotton fiber, bamboo fiber, ramie fiber and sisal fiber.

5. The preparation process of the negative oxygen ion air purification material according to claim 1, characterized in that, In step S2, the mass ratio of nano tourmaline powder, double-bond silane coupling agent and β-cyclodextrin is 1:(0.1 - 0.5):(1.5 - 3).

6. The preparation process of the negative oxygen ion air purification material according to claim 1, characterized in that, In step S1, the mass ratio of the nano tourmaline powder to the water-soluble polyethylene glycol is 1:(0.5 - 1).

7. The preparation process of the negative oxygen ion air purification material according to claim 4, characterized in that, In step S2, the mass ratio of nano tourmaline powder to starch is 1:(2 - 5).

8. A negative oxygen ion air purification material, characterized in that, Prepared by the preparation process according to any one of claims 1 - 7.