Photodynamic antibacterial fiber as well as preparation method and application thereof

Abstract

The invention relates to a photodynamic antibacterial fiber as well as a preparation method and application thereof. The preparation method of the photodynamic antibacterial fiber comprises the following steps: S1, preparing a bismuth sulfide / Michelene composite material; s2, mixing the bismuth sulfide / Michelene composite material with spinning slices, a coupling agent, a lubricant and a nucleating agent to obtain a mixture; and S3, carrying out melt electrostatic spinning on the mixture. The Bi2S3 / MXene composite material is prepared by coupling an n-type direct band gap semiconductor Bi2S3 with excellent photosensitivity and good absorption capability in a wide wavelength with MXene with excellent conductivity, relatively strong light absorption and conversion capability and good biocompatibility, so that the electron hole separation efficiency and the light absorption capability of the semiconductor can be effectively improved; the Bi2S3 / MXene composite material which can realize full-wave-band photodynamic antibiosis and has high ROS yield is constructed, so that the antibiosis efficiency of the prepared fiber is improved.

Description

Technical Field

[0001] The present application relates to the technical field of textiles, and in particular to a photodynamic antibacterial fiber and a preparation method and application thereof. Background Art

[0002] Photodynamic antibacterial is an effective antibacterial technology. Its principle is: in the presence of molecular oxygen, photosensitizers produce active oxygen that can kill microorganisms under visible light irradiation, the most important of which is singlet oxygen. Since singlet oxygen and free radicals cause non-specific cell damage, photodynamic antibacterial is also effective against drug-resistant strains, and will not induce new bacterial resistance in multiple photosensitization. At the same time, the instantaneous life cycle of active oxygen ensures the environmental friendliness of photosensitizers. Photodynamic antibacterial has the advantages of being effective against a variety of pathogens (bacteria, viruses, fungi), being equally effective against drug-resistant strains and drug-sensitive strains, not inducing new bacterial resistance, and not causing safety hazards when in contact with human skin. It has attracted widespread attention, especially in the field of textiles. By integrating photodynamic antibacterial materials into textiles, textiles can be given photodynamic antibacterial properties.

[0003] At present, photodynamic antibacterial mainly uses photocatalysts for antibacterial disinfection under the action of ultraviolet rays. In this regard, Japan is a leading country. Toshiba of Japan has developed a new generation of photocatalyst products with leading level, namely photodynamic functional fibers. my country has only started gradually since 2000. Cai Zaisheng and others from Donghua University have conducted experiments on high-speed rail curtains through thick interlayer composite fabrics. Photodynamic materials represented by titanium dioxide are widely used in the study of antibacterial and indoor environmental purification because of their excellent photocatalytic oxidation performance. The material is deposited or compounded on the surface of the textile substrate by post-finishing method, magnetron sputtering method, surface grafting polymerization method and other methods. However, photocatalysts represented by titanium dioxide have the following defects when applied to textiles: low spectral utilization, mainly used in the ultraviolet region (254-380nm), narrow spectrum, low antibacterial efficiency, and cannot be permanently attached to the fiber surface. It can only be applied to the fiber surface through post-finishing methods such as coating, with poor wear resistance and washability, hard feel, and affecting product quality. There are also studies that extend it to the visible spectrum region, but the antibacterial efficiency is still low. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a photodynamic antibacterial fiber and a preparation method and application thereof to solve the above-mentioned technical problems such as narrow spectrum, low antibacterial efficiency, poor wear and wash resistance, hard feel, and affecting product quality.

[0005] To achieve the above objectives, the scheme of this application is as follows:

[0006] In a first aspect, the present invention provides a method for preparing a photodynamic antibacterial fiber, comprising the following steps:

[0007] S1. Bi2S3 / MXene composite material (Bi2S3 / MXene composite material) was prepared by hydrothermal method;

[0008] S2. The bismuth sulfide / Michael ene composite material is mixed with a spinning chip, a coupling agent, a lubricant and a nucleating agent to obtain a mixture;

[0009] S3. The mixture is subjected to melt electrospinning to obtain the photodynamic antibacterial fiber.

[0010] Optionally, in step S1, the bismuth sulfide / michaelene composite material is prepared by a hydrothermal method, including: adding a bismuth source and michaelene to a solvent to obtain a mixed solution, adding a sulfur source to the mixed solution and performing a solvent thermal reaction, washing, drying, and grinding to obtain the bismuth sulfide / michaelene composite material.

[0011] It should be noted that in this application, mikene includes but is not limited to: titanium carbide (TiC), Ti2CT x 、Ti3C2T x 、Ti3CNT x 、Nb2CT x 、Ta2CT x 、Ti2CT x 、Ti3C2T x wait.

[0012] Optionally, in step S1, the bismuth source is selected from at least one of an inorganic bismuth salt, bismuth 2-ethylhexanoate and bismuth trioxide.

[0013] It should be noted that, in the present application, the inorganic bismuth source includes but is not limited to: bismuth trichloride, bismuth nitrate, etc.

[0014] Optionally, in step S1, the mass ratio of the bismuth source to the michalene is 0.2-3:1, preferably 0.5-2:1.

[0015] Optionally, in step S1, the sulfur source is selected from at least one of thiourea, thioacetamide, phenylthiourea and inorganic sulfur salts.

[0016] Optionally, in step S1, the mass ratio of the sulfur source to the michalene is 0.1-2:1, preferably 0.2-1:1.

[0017] Optionally, in the mixed solution of step S1, the concentration of michelene is 0.05-0.5 g / mL, preferably 0.1%-0.3% g / mL.

[0018] Optionally, in step S1, the solvent is selected from at least one of ethanol, polyols, chloroform, tetrahydrofuran, N,N-dimethylformamide, propylene carbonate, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetophenone, acetonitrile and dioxane.

[0019] It should be noted that, in the present application, polyols include but are not limited to: ethylene glycol, 1,2-propylene glycol, etc.

[0020] Optionally, in step S1, the temperature of the solvent thermal reaction is 180-250°C, preferably 200-250°C; the duration of the solvent thermal reaction is 30-120 min, preferably 45-120 min.

[0021] Optionally, in step S2, the spinning slice is selected from at least one of a polypropylene slice (PP slice for short in English), a polyethylene slice (PE slice for short in English), a polyethylene terephthalate slice (PBT slice for short in English), a polybutylene terephthalate slice (PA slice for short in English), a polyamide slice (PLA slice for short in English), a polylactic acid slice (PHA slice for short in English), a polyhydroxyalkanoate slice (PHA slice for short in English), a polycaprolactone slice (PCL slice for short in English) and a polyglycolide slice (PGA slice for short in English).

[0022] Optionally, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the bismuth sulfide / michaelene composite material is 1.0wt%-5.0wt%, preferably 2.0wt%-5.0wt%.

[0023] Optionally, in step S2, the coupling agent is selected from a silane coupling agent.

[0024] Optionally, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the coupling agent is 0.2wt%-2.0wt%, preferably 0.5wt%-2.0wt%.

[0025] Optionally, in step S2, the silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane (ie, KH-550), γ-aminopropyltrimethoxysilane (ie, KH-540), isocyanatepropyltriethoxysilane and γ-isocyanatepropyltrimethoxysilane.

[0026] Optionally, in step S2, the lubricant is selected from at least one of vinyl bisstearamide, paraffin, polyethylene wax and stearate.

[0027] Optionally, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the lubricant is 0.2wt%-1.0wt%, preferably 0.5wt%-1.0wt%.

[0028] Optionally, in step S2, the nucleating agent is selected from at least one of nano-talc, nano-calcium carbonate and nano-boron nitride.

[0029] Optionally, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the nucleating agent is 0.2wt%-0.8wt%, preferably 0.5wt%-0.8wt%.

[0030] Optionally, in step S2, mixing is performed at a rotation speed of 1500-2500 r / min for 3-15 min, preferably, mixing is performed at a rotation speed of 2000-2500 r / min for 5-15 min.

[0031] Optionally, in the melt electrospinning process of step S3, the temperature is 180-300°C, preferably 200-300°C; the spinning distance is 5-50cm, preferably 10-50cm; the spinning voltage is 10-40kV, preferably 15-40kV; and the winding drum speed is 50-200r / min, preferably 80-200r / min.

[0032] In a second aspect, the present invention also provides a photodynamic antibacterial fiber prepared according to the method described above.

[0033] In a third aspect, the present invention further provides a fabric made of the photodynamic antibacterial fiber as described above.

[0034] Beneficial effects of the present invention:

[0035] Different from traditional quaternary ammonium salts and metal ion antibacterial agents, the photodynamic antibacterial fiber of the present application is based on the photodynamic principle for antibacterial effects. It can generate active oxygen on the surface of the material through light irradiation and thus achieve high efficiency in antibacterial effects. It has the advantages of high efficiency, low tolerance, safety, and environmental friendliness.

[0036] The present application couples an n-type, direct bandgap (e.g., 1.3-1.7 eV) semiconductor Bi2S3 with a tight bandgap energy, excellent photosensitivity, and good absorption capacity in a wide wavelength (visible light) with a MXene with excellent conductivity, strong light absorption conversion capability, and good biocompatibility to form a Bi2S3 / MXene composite material, which can effectively improve the electron-hole separation efficiency and light absorption capacity of the semiconductor, and construct a photodynamic antibacterial agent Bi2S3 / MXene composite material that has good light response activity in ultraviolet, visible, and infrared, can achieve full-band photodynamic antibacterial and has a high ROS yield, thereby improving the antibacterial properties of fabrics made of fibers made of the Bi2S3 / MXene composite material, and overcoming the defects of Bi2S3 such as serious photogenerated carrier recombination, low specific surface area, and low reduction potential.

[0037] The photodynamic antibacterial fiber of the present application is made by using the electrostatic spinning technology of ultrafine fibers, that is, the present application utilizes the characteristics of electrostatic spinning to produce a larger specific surface area, promotes the generation, separation and transmission of photogenerated current-carrying electrons, thereby enhancing the efficiency of the generation of active oxygen, and further enables the photodynamic antibacterial fiber to exhibit a more excellent antibacterial effect. At the same time, it overcomes the disadvantages of solution electrostatic spinning, which is that due to the high conductivity of the solution and the free movement of electrons, the solute is easily stretched to fibers of two to three hundred nanometers to several microns during the complex whipping process, but the polymer solvent is generally an organic solvent such as chloroform and acetone, which will cause serious production safety risks and environmental protection hazards.

[0038] The photodynamic antibacterial fiber of the present application is spun by melt electrospinning. The spinning process does not involve solvents, the raw materials are completely converted into fibers, the yield is high, and the production process is safe and environmentally friendly. At the same time, by introducing Bi2S3 / MXene composite materials into the spinning melt, the conductivity of the melt can be enhanced, overcoming the technical problems such as weak jet whipping and difficult refinement caused by limitations such as high melt viscosity, poor conductivity, and rapid jet cooling.

[0039] This application uses a specific silane coupling agent to achieve covalent connection between functional additives and polymer matrices, thereby improving the dispersibility and compatibility of Bi2S3 / MXene composite materials in the polymer matrix, thereby effectively controlling the viscosity of the spinning melt, and improving the limitations of melt electrospinning such as high melt viscosity, poor conductivity, and rapid jet cooling that cause weak jet whipping and difficult refinement, thereby improving the antibacterial properties of the manufactured fibers.

[0040] The photodynamic antibacterial fiber made by electrospinning in this application has more efficient and lasting antibacterial activity. The photodynamic antibacterial agent is firmly bound inside the fiber, avoiding the problems of antibacterial material shedding and antibacterial effect decay caused by multiple washing processes of textiles, thereby improving the durability of the antibacterial performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 B obtained in step S1 of Example 1 i2 Specific surface area and pore size distribution of S3 / MXene composite materials, A is the specific surface area diagram, B is the particle size distribution diagram, Relative Pressure represents relative pressure, Quantity Adsorbed represents adsorption amount, Pore Width represents pore width, and Pore Volume represents pore volume;

[0042] Figure 2 The figure is the result of the ultraviolet-visible light absorption spectrum test of the photodynamic antibacterial fiber prepared in Example 1, Wavelength represents the wavelength, and Adsorbance represents the absorption intensity (absorbance);

[0043] Figure 3 B obtained in step S1 of Example 1 i2 The antibacterial performance test results of S3 / MXene composite materials under dark room and infrared light, respectively. Dark means dark room (i.e. dark conditions), and Light means light, the same below;

[0044] Figure 4 B obtained in step S1 of Example 1 i2 The antibacterial performance test results of S3 / MXene composite materials under dark room and ultraviolet light respectively;

[0045] Figure 5 B obtained in step S1 of Example 1 i2 The antibacterial performance test results of S3 / MXene composite materials under dark room and visible light respectively. DETAILED DESCRIPTION

[0046] The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0047] An embodiment of the present invention provides a method for preparing a photodynamic antibacterial fiber, comprising the following steps:

[0048] S1. A bismuth sulfide / michaelene composite material is prepared by a hydrothermal method: a bismuth source and michaelene are added to a solvent to obtain a mixed solution having a michaelene concentration of 0.05-0.5 g / mL, a sulfur source is added to the mixed solution and a solvent thermal reaction is carried out at a temperature of 180-250° C. for 30-120 min, and then the mixture is washed, dried, and ground to obtain a bismuth sulfide / michaelene composite material;

[0049] The bismuth source is selected from at least one of inorganic bismuth salts, bismuth 2-ethylhexanoate and bismuth trioxide, the mass ratio of the bismuth source to michalene is 0.2-3:1, the sulfur source is selected from at least one of thiourea, thioacetamide, phenylthiourea and inorganic sulfur salts, the mass ratio of the sulfur source to michalene is 0.1-2:1, and the solvent is selected from at least one of ethanol, polyols, chloroform, tetrahydrofuran, N,N-dimethylformamide, propylene carbonate, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetophenone, acetonitrile and dioxane;

[0050] S2. The bismuth sulfide / Michael ene composite material is mixed with the spinning slice, the silane coupling agent, the lubricant and the nucleating agent at a speed of 1500-2500r / min for 3-15min to obtain a mixture;

[0051] The spinning slice is selected from at least one of polypropylene slice, polyethylene slice, polyethylene terephthalate slice, polybutylene terephthalate slice, polyamide slice, polylactic acid slice, polyhydroxyalkanoate slice, polycaprolactone slice and polyglycolide slice, the silane coupling agent is selected from at least one of γ-aminopropyl triethoxysilane, γ-aminopropyl trimethoxysilane, isocyanate propyl triethoxysilane and γ-isocyanate propyl trimethoxysilane, the lubricant is selected from at least one of vinyl bisstearamide, paraffin, polyethylene wax and stearate, the nucleating agent is selected from at least one of nano talc, nano calcium carbonate and nano boron nitride, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the bismuth sulfide / michaelene composite material is 1.0wt%-5.0wt%, the mass of the silane coupling agent is 0.2wt%-2.0wt%, the mass of the lubricant is 0.2wt%-1.0wt%, and the mass of the nucleating agent is 0.2wt%-0.8wt%;

[0052] S3. The mixture is subjected to melt electrospinning at a temperature of 180-300° C., a spinning distance of 5-50 cm, a spinning voltage of 10-40 kV and a winding drum speed of 50-200 r / min to obtain a photodynamic antibacterial fiber.

[0053] Another embodiment of the present invention also provides a photodynamic antibacterial fiber prepared according to the method as described above.

[0054] Another embodiment of the present invention further provides a fabric made of the photodynamic antibacterial fiber as described above.

[0055] In the following description, a lot of details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. The following examples only list titanium carbide (TiC) as the specific case of mikheline. Those skilled in the art may also choose Ti2CTx 、Ti3C2T x 、Ti3CNT x 、Nb2CT x 、Ta2CT x 、Ti2CT x 、Ti3C2T x etc as michelene.

[0056] Example 1

[0057] A method for preparing a photodynamic antibacterial fiber, the specific steps are as follows:

[0058] S1. Preparation of B by hydrothermal method i2 S3 / MXene composite material: 42.5 g of bismuth nitrate pentahydrate and 50 g of MXene (titanium carbide is used here) are added to 500 mL of ethylene glycol to obtain a mixed solution with a MXene concentration of 0.1 g / mL. 10 g of thiourea is added to the mixed solution and a solvent thermal reaction is carried out at 200 ° C for 40 min. The mixture is washed, dried, and ground to obtain B i2 S3 / MXene composites;

[0059] S2. 5g B i2 The S3 / MXene composite material was mixed with 250 g of PET chips, 2.5 g of γ-aminopropyltriethoxysilane (i.e., KH-550), 0.75 g of vinyl bisstearamide, and 0.75 g of nano-talc at a rotation speed of 1500 r / min for 4 min to obtain a mixture;

[0060] S3. The mixture was subjected to melt electrospinning at a temperature of 285° C., a spinning distance of 10 cm, a spinning voltage of 35 kV and a winding drum speed of 100 r / min to obtain a photodynamic antibacterial fiber.

[0061] Example 2

[0062] A method for preparing a photodynamic antibacterial fiber, the specific steps are as follows:

[0063] S1. Preparation of B by hydrothermal method i2 S3 / MXene composite material: 20 g of bismuth 2-ethylhexanoate and 100 g of MXene (titanium carbide is used here) are added to 500 mL of tetrahydrofuran to obtain a mixed solution with a MXene concentration of 0.2 g / mL. 10 g of thioacetamide is added to the mixed solution and a solvent thermal reaction is carried out at 180°C for 120 min. The mixture is washed, dried, and ground to obtain B i2 S3 / MXene composites;

[0064] S2. 3g B i2The S3 / MXene composite material was mixed with 297 g of PET chips, 0.6 g of γ-aminopropyltrimethoxysilane (i.e., KH-540), 3.0 g of paraffin wax, and 2.4 g of nano boron nitride agent at a rotation speed of 2500 r / min for 3 min to obtain a mixture;

[0065] S3. The mixture was subjected to melt electrospinning at a temperature of 180° C., a spinning distance of 15 cm, a spinning voltage of 10 kV and a winding drum speed of 200 r / min to obtain a photodynamic antibacterial fiber.

[0066] Example 3

[0067] A method for preparing a photodynamic antibacterial fiber, the specific steps are as follows:

[0068] S1. Preparation of B by hydrothermal method i2 S3 / MXene composite material: 300 g of bismuth trioxide and 150 g of MXene (titanium carbide is used here) are added to 500 mL of N,N-dimethylformamide to obtain a mixed solution with a MXene concentration of 0.3 g / mL. 150 g of thioacetamide is added to the mixed solution and a solvent thermal reaction is carried out at 250 ° C for 30 min. The mixture is washed, dried, and ground to obtain B i2 S3 / MXene composites;

[0069] S2. 9g B i2 The S3 / MXene composite material was mixed with 291 g of PET chips, 6 g of γ-isocyanatepropyltrimethoxysilane, 0.6 g of sodium stearate and 0.6 g of nano-calcium carbonate at a rotation speed of 2000 r / min for 6 min to obtain a mixture;

[0070] S3. The mixture was subjected to melt electrospinning at a temperature of 300° C., a spinning distance of 5 cm, a spinning voltage of 40 kV and a winding drum speed of 50 r / min to obtain a photodynamic antibacterial fiber.

[0071] Example 4

[0072] A method for preparing a photodynamic antibacterial fiber, the specific steps are as follows:

[0073] S1. Preparation of B by hydrothermal method i2 S3 / MXene composite material: 150 g of bismuth trioxide and 50 g of MXene (titanium carbide is used here) are added to 500 mL of chloroform to obtain a mixed solution with a MXene concentration of 0.1 g / mL. 100 g of sodium sulfide is added to the mixed solution and a solvent thermal reaction is carried out at 220°C for 60 min. The mixture is washed, dried, and ground to obtain B i2 S3 / MXene composites;

[0074] S2. 15 g of bismuth sulfide / Michael ene composite material was mixed with 285 g of PET slices, 3.0 g of isocyanate propyl triethoxysilane, 1.5 g of polyethylene wax and 1.5 g of nano-calcium carbonate at 2100 r / min speed for 7 min to obtain a mixture;

[0075] S3. The mixture was subjected to melt electrospinning at a temperature of 250° C., a spinning distance of 20 cm, a spinning voltage of 20 kV and a winding drum speed of 100 r / min to obtain a photodynamic antibacterial fiber.

[0076] Comparative Example 1

[0077] The photodynamic antibacterial fiber was prepared in the same manner as in Example 1 except for the following conditions:

[0078] S1. Add 42.5 g of bismuth nitrate pentahydrate to 500 mL of ethylene glycol, add 10 g of thiourea and perform solvent thermal reaction at 200 ° C for 40 min, wash, dry and grind to obtain B i2 S3 materials;

[0079] S2. 5g B i2 The S3 material was mixed with 250 g of PET chips, 2.5 g of γ-aminopropyltriethoxysilane (ie, KH-550), 0.75 g of vinyl bisstearamide and 0.75 g of nano talc at a rotation speed of 1500 r / min for 4 min to obtain a mixture.

[0080] That is, in this comparative example, bismuth sulfide and michalcene are not coupled, and only bismuth sulfide is added.

[0081] Comparative Example 2

[0082] The photodynamic antibacterial fiber was prepared in the same manner as in Example 1 except for the following conditions:

[0083] S2. 5 g of MXene material was mixed with 250 g of PET chips, 2.5 g of γ-aminopropyltriethoxysilane (ie, KH-550), 0.75 g of vinyl bisstearamide and 0.75 g of nano talc at a rotation speed of 1500 r / min for 4 min to obtain a mixture.

[0084] That is, in this comparative example, bismuth sulfide and michalcone are not coupled, and only michalcone is added.

[0085] Comparative Example 3

[0086] The photodynamic antibacterial fiber was prepared in the same manner as in Example 1 except for the following conditions:

[0087] S3. The mixture is melt-spinned at a temperature of 275° C. to obtain photodynamic antibacterial fibers.

[0088] That is, the spinning in this comparative example is carried out by a common process rather than a melt electrostatic process.

[0089] Comparative Example 4

[0090] The photodynamic antibacterial fiber was prepared in the same manner as in Example 1 except for the following conditions:

[0091] S2. 5g B i2 The S3 / MXene composite material was mixed with 250 g of PET chips, 0.75 g of vinyl bisstearamide and 0.75 g of nano talc at a rotation speed of 1500 r / min for 4 min to obtain a mixture.

[0092] That is, no coupling agent was added in this comparative example.

[0093] Performance Testing

[0094] The B prepared in step S1 of Example 1 was detected by a nitrogen adsorption desorption instrument. i2 The specific surface area and pore size distribution of S3 / MXene composite materials are shown in Figure 1 shown.

[0095] Depend on Figure 1 It can be seen that the isotherms of the Bi2S3 / MXene composite material prepared in Example 1 show obvious hysteresis loops in the range of (P / P0) 0.6-1.0, indicating that the Bi2S3 / MXene composite material prepared in the present invention has a mesoporous / microporous structure; the mesopore diameter of the Bi2S3 / MXene composite material prepared in Example 1 is mainly distributed in the range of 5-15 nm, the pore size distribution is narrow, and the specific surface area is 12.8 m 2 / g, indicating that the Bi2S3 / MXene composite material prepared in the present invention has a large specific surface area. Obviously, the Bi2S3 / MXene composite material prepared in the present invention has a mesoporous / microporous structure and a large specific surface area.

[0096] The photodynamic composite material prepared in Example 1 was subjected to UV-visible absorption spectrum detection using a UV-2600 UV-visible absorption spectrometer (UV-vis) from Shimadzu Corporation. The results are as follows: Figure 2 shown.

[0097] Depend on Figure 2 It can be seen that there is strong and broad absorption in the 200nm-800nm ​​band in the spectrum. This is because the electrons on the surface of the material are excited to move from the valence band to the conduction band. This result shows that B i2S3 / MXene composite materials can be used as photocatalysts and have a good light response range and intensity. When used in fiber materials, they can improve the fiber's utilization of light energy and increase the fiber's photodynamic function.

[0098] The fiber obtained in Example 1 was woven into a fabric. The fabric was irradiated with near-infrared light (780-1100 nm) for different time periods (5, 10, 20, and 30 min). The antibacterial properties of the fabric against Escherichia coli (E. coli) were tested under dark and light conditions. The results are as follows: Figure 3 And as shown in Table 1.

[0099] Table 1 Antibacterial rate of fabrics against Escherichia coli under dark and near-infrared light for different time periods (%)

[0100] Light (min) Antibacterial rate under dark conditions Antibacterial rate under light conditions 5 18 63 10 37 91 20 50 ＞99 30 62 ＞99

[0101] The fibers obtained in Example 1 were woven into fabrics. The fabrics were irradiated with a tungsten lamp (visible light, 480-780 nm) for different periods of time. The antibacterial properties of the fabrics against Escherichia coli (E. coli) were measured under dark and light conditions. The results are as follows: Figure 4 and Table 2 are as follows.

[0102] Table 2 Antibacterial rate of fabrics against Escherichia coli at different times of exposure to dark and visible light (%)

[0103]

[0104]

[0105] The fibers obtained in Example 1 were woven into fabrics. The fabrics were irradiated with ultraviolet light (100-400 nm) for different periods of time. The antibacterial properties of the fabrics against Staphylococcus aureus (S. aureus) were tested under dark and light conditions. The results are as follows: Figure 5 And as shown in Table 3.

[0106] Table 3 Antibacterial rate of fabrics against Staphylococcus aureus in the dark and under UV light for different time periods (%)

[0107] Light exposure time (min) Antibacterial rate under dark conditions Antibacterial rate under light conditions 1 24 44 3 36 ＞99 5 48 ＞99 10 36 ＞99 15 35 ＞99

[0108] Depend on Figure 3 , Figure 4 , Figure 5It can be seen from Table 1, Table 2 and Table 3 that the photodynamic antibacterial fiber obtained by the present invention has a good antibacterial effect under the irradiation of ultraviolet light, visible light and near-infrared full-band spectrum; compared with dark conditions, the antibacterial effect achieved by photodynamics is significant. First of all, ultraviolet rays themselves have a certain bactericidal effect. They have high energy and can destroy the molecular structure of DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) in the cells of microbial organisms, causing growth cell death and / or regenerative cell death. In addition, combined with the excellent light response activity of Bi2S3 / MXene materials, due to the higher light absorption capacity and electron and hole separation efficiency, more ROS are generated, causing bacterial DNA and protein damage, cell membrane damage and inactivation and death. Therefore, under ultraviolet irradiation conditions, the bactericidal effect is more efficient and significant, that is, the antibacterial rate of Staphylococcus aureus can reach more than 99% after 3 minutes of illumination. Under visible light and near-infrared light conditions, Bi2S3 / MXene generates electron holes after light excitation, which react with oxygen, water, etc. to generate active free radicals such as superoxide radicals (·O2-) and hydroxyl radicals (·OH) to inactivate microorganisms, and MXene photosensitive materials generate heat after light exposure, which can cause irreversible denaturation and death of bacterial proteins. The antibacterial rate of Escherichia coli can reach more than 99% within 20-30 minutes. In summary, the Bi2S3 / MXene antibacterial fiber of the present invention has a strong bactericidal effect in the ultraviolet, visible, and infrared bands.

[0109] The fiber diameter, breaking strength and breaking elongation of the photodynamic antibacterial fibers prepared in Examples 1-4 and Comparative Examples 1-4 were tested, and the results are shown in Table 4;

[0110] Among them, the fiber diameter was measured by microscopy;

[0111] The breaking strength and elongation at break are tested in accordance with GB / T 14344-2022 Test method for tensile properties of chemical fiber filaments.

[0112] Table 4 Test results of fiber diameter, breaking strength and breaking elongation

[0113] Group Fiber diameter / nm Breaking strength (cN / dtex) Elongation at break (%) Example 1 120 3.05 55.7 Example 2 115 3.00 54.5 Example 3 150 2.75 48.8 Example 4 135 2.99 53.2 Comparative Example 1 200 2.55 43.5 Comparative Example 2 150 2.48 47.2 Comparative Example 3 4200 3.27 65.9 Comparative Example 4 350 2.12 26.8

[0114] As shown in Table 4, the optical fiber prepared in Examples 1-4 has a fiber diameter of 115-150 nm, a breaking strength of 2.75-3.05 cN / dtex, and a breaking elongation of 48.8%-55.7%. The results show that the optical fiber prepared in the present invention has excellent mechanical properties.

[0115] The photodynamic antibacterial fibers prepared in Examples 1-4 and Comparative Examples 1-5 were made into fabrics, and samples were taken from each fabric. The dissolution of each sample was tested according to "GB / T 31713-2015 Dissolution Test of Antibacterial Substances in Antibacterial Textiles for Safety", and the results are shown in Table 5;

[0116] According to GB / T 20944.3-2008 Evaluation of antibacterial properties of textiles Part 3: Oscillation method, the antibacterial rates of each sample against Candida albicans, Escherichia coli and Staphylococcus aureus were tested, and the results are shown in Table 6;

[0117] Samples were taken from each fabric and washed 50 times. The antibacterial rate of each sample against Candida albicans, Escherichia coli and Staphylococcus aureus was tested again according to "GB / T 20944.3-2008 Evaluation of antibacterial properties of textiles Part 3: Oscillation method". The results are shown in Table 6.

[0118] Table 5 Dissolution test results

[0119]

[0120]

[0121] The width of the inhibition zone is an important indicator for evaluating the safety of antibacterial textiles. It can be seen from Table 5 that the width of the inhibition zone of the fabrics made of the photodynamic antibacterial fibers prepared in Examples 1-4 for Candida albicans, Escherichia coli and Staphylococcus aureus is 0 mm. The results show that the antibacterial substances in the photodynamic antibacterial fibers of the present invention are non-dissolving, can be firmly combined with the fibers, have excellent safety, and the fabrics prepared have a lasting antibacterial effect. The comparative example 4 has a certain degree of dissolution because no coupling agent is added during the spinning process. The Bi2S3 / MXene material is only physically mixed in the fiber matrix, and there is a certain instability and easy to fall off, which leads to a slight dissolution of the antibacterial substances in the fabric, resulting in the antibacterial durability being affected in actual use and there are certain safety hazards. The comparative example 1 has a slight dissolution, which may be due to the lack of the introduction of MXene, the high viscosity of the spinning melt, and the poor conductivity, which leads to a certain impact on the electrospinning effect, and then the functional additive components are slightly less stable in the fiber matrix. In Comparative Examples 2 and 3, since the systems are relatively stable, the functional additive components can be stably combined inside the fibers, and therefore the antibacterial substances are not dissolved, proving that the materials have a certain degree of safety.

[0122] Table 6 Antibacterial rate test results

[0123]

[0124] Note: In this table, > means exceeding the detection limit of 99% (subject to the test report results of Fujian Fiber Inspection).

[0125] As shown in Table 6, compared with Comparative Examples 1 and 2, Example 1 has significantly improved antibacterial properties against Candida albicans, Escherichia coli and Staphylococcus aureus. The results show that the present application couples the n-type, direct bandgap (such as 1.3-1.7 eV) semiconductor Bi2S3 with tight bandgap energy, excellent photosensitivity and good absorption capacity in a wide wavelength (visible light) with MXene with excellent conductivity, strong light absorption conversion ability and good biocompatibility to form a Bi2S3 / MXene composite material, which can effectively improve the electron-hole separation efficiency and light absorption capacity of the semiconductor, and construct a photodynamic antibacterial agent Bi2S3 / MXene composite material with good light response activity for ultraviolet-visible-infrared, which can achieve full-band photodynamic antibacterial and has a high ROS yield, thereby improving the antibacterial properties of the fabric processed from the prepared fiber.

[0126] It can be seen from the embodiments and comparative examples that the spinning process of comparative example 3 adopts the melt spinning method. The results show that the ideal ultrafine fiber structure cannot be spun out. The average fiber diameter is above 4000nm, which is close to 40 times the spinning method in Examples 1-4. The thicker fiber diameter causes most of Bi2S3 / MXene to be wrapped inside the fiber, and its photodynamic antibacterial function cannot be maximized. The ultrafine fibers obtained by electrospinning can greatly increase the specific surface area, promote the generation, separation and transmission of photogenerated current-carrying electrons, thereby enhancing the efficiency of active oxygen generation, and then make the photodynamic antibacterial fiber show a better antibacterial effect, giving full play to the functional properties of the material. In addition, compared with solution electrospinning, due to the need to use organic solvents such as chloroform and acetone, and the harsh dissolution conditions, spinning is difficult, and it will also cause serious production safety risks and environmental protection hazards. This application adopts melt electrospinning. The spinning process does not involve solvents. The raw materials are completely converted into fibers with high yield. The production process is safe and environmentally friendly. It is safe, efficient, green and environmentally friendly. At the same time, by introducing Bi2S3 / MXene composite materials into the spinning melt, the conductivity of the melt can be enhanced, overcoming the technical problems such as weak jet whipping and difficult refinement caused by limitations such as high melt viscosity, poor conductivity, and rapid jet cooling.

[0127] It can be seen from Table 6 that compared with Comparative Example 4, the antibacterial effect of Example 1 on Candida albicans, Escherichia coli and Staphylococcus aureus still has a very high retention rate after washing, while the antibacterial rate of Comparative Example 4 after washing has declined to a large extent. The results show that the present application realizes the covalent connection of the functional additive and the polymer matrix through a specific silane coupling agent, improves the dispersibility and compatibility of the Bi2S3 / MXene composite material in the polymer matrix, thereby effectively controlling the viscosity of the spinning melt, improving the high melt viscosity and poor conductivity of the melt electrospinning, and improving the technical problems such as weak jet whipping and difficult refinement caused by the limitations of fast jet cooling, thereby obtaining electrospun fibers with finer diameters, larger specific surface areas and more stable performance, giving full play to the antibacterial effect of the functional additive Bi2S3 / MXene, and improving the antibacterial properties of the prepared fibers.

[0128] As shown in Table 6, after washing, the antibacterial rate of the fabric made of the photodynamic antibacterial fiber prepared in Comparative Examples 1-4 decreased significantly, while the fabric made of the photodynamic antibacterial fiber prepared in Examples 1-4 did not change significantly. This result shows that the photodynamic antibacterial fiber prepared by electrospinning in this application has more efficient and lasting antibacterial activity, and the photodynamic antibacterial agent is firmly combined inside the fiber, avoiding the problems of antibacterial material shedding and antibacterial effect decay caused by multiple washing processes of textiles, thereby improving the durability of antibacterial performance.

[0129] 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 technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for preparing a photodynamic antibacterial fiber, characterized in that: The following steps are involved: S1. Preparation of bismuth sulfide / michaelene composites by hydrothermal method; S2. The bismuth sulfide / Michael ene composite material is mixed with a spinning chip, a coupling agent, a lubricant and a nucleating agent to obtain a mixture; S3. The mixture is subjected to melt electrospinning to obtain the photodynamic antibacterial fiber.

2. The method for preparing the photodynamic antibacterial fiber according to claim 1, characterized in that: In step S1, the bismuth sulfide / michaelene composite material is prepared by a hydrothermal method, including: adding a bismuth source and michaelene to a solvent to obtain a mixed solution, adding a sulfur source to the mixed solution and performing a solvent thermal reaction, washing, drying, and grinding to obtain the bismuth sulfide / michaelene composite material.

3. The method for preparing the photodynamic antibacterial fiber according to claim 2, characterized in that: In step S1, the bismuth source is selected from at least one of an inorganic bismuth salt, bismuth 2-ethylhexanoate and bismuth trioxide; And / or, in step S1, the mass ratio of the bismuth source to the michalcone is 0.2-3:1; And / or, in step S1, the sulfur source is selected from at least one of thiourea, thioacetamide, phenylthiourea and inorganic sulfur salt; And / or, in step S1, the mass ratio of the sulfur source to the michalcene is 0.1-2:1; And / or, in step S1, the solvent is selected from at least one of ethanol, polyol, chloroform, tetrahydrofuran, N,N-dimethylformamide, propylene carbonate, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetophenone, acetonitrile and dioxane; And / or, in the mixed solution of step S1, the concentration of michelene is 0.05-0.5 g / mL.

4. The method for preparing the photodynamic antibacterial fiber according to claim 2, characterized in that: In step S1, the temperature of the solvent thermal reaction is 180-250° C., and the duration of the solvent thermal reaction is 30-120 min.

5. The method for preparing the photodynamic antibacterial fiber according to claim 1, characterized in that: In step S2, the spinning slice is selected from at least one of a polypropylene slice, a polyethylene slice, a polyethylene terephthalate slice, a polybutylene terephthalate slice, a polyamide slice, a polylactic acid slice, a polyhydroxyalkanoate slice, a polycaprolactone slice and a polyglycolide slice; And / or, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the bismuth sulfide / michaelene composite material is 1.0wt%-5.0wt%; And / or, in step S2, the coupling agent is selected from a silane coupling agent; And / or, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the coupling agent is 0.2wt%-2.0wt%.

6. The method for preparing the photodynamic antibacterial fiber according to claim 5, characterized in that: In step S2, the silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, isocyanatepropyltriethoxysilane and γ-isocyanatepropyltrimethoxysilane.

7. The method for preparing the photodynamic antibacterial fiber according to claim 1, characterized in that: In step S2, the lubricant is selected from at least one of vinyl bisstearamide, paraffin, polyethylene wax and stearate; And / or, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the lubricant is 0.2wt%-1.0wt%; And / or, in step S2, the nucleating agent is selected from at least one of nano-talc, nano-calcium carbonate and nano-boron nitride; And / or, in step S2, based on the total mass of the bismuth sulfide / michaelene composite material and the spinning slice, the mass of the nucleating agent is 0.2wt%-0.8wt%.

8. The method for preparing the photodynamic antibacterial fiber according to claim 1, characterized in that: In step S2, mixing at a speed of 1500-2500 r / min for 3-15 min; And / or, in the melt electrospinning process of step S3, the temperature is 180-300° C., the spinning distance is 5-50 cm, the spinning voltage is 10-40 kV, and the winding drum speed is 50-200 r / min.

9. A photodynamic antibacterial fiber prepared according to the method according to any one of claims 1 to 8.

10. A fabric, characterized in that: It is made of the photodynamic antibacterial fiber described in claim 9.

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