1. An elastic fiber, comprising the following components: glycidyl methacrylate grafted polystyrene PS-GMA, polyurethane TPU; the mass ratio of PS-GMA to TPU is 1: (3-7).

2. The elastic fiber of claim 1, wherein the mass ratio of PS-GMA to TPU is 1: 5.

3. the elastic fiber according to claim 1 or 2, wherein the PS-GMA is polymerized from styrene and glycidyl methacrylate, and the molar ratio of the styrene to the glycidyl methacrylate is (1-5): 1, preferably 2: 1.

4. The elastic fiber according to any one of claims 1 to 3, wherein the PS-GMA is spun-compounded with TPU; preferably, the spinning is wet spinning, dry spinning or melt spinning.

5. The elastic fiber according to claim 4, further comprising an antibacterial agent, wherein the antibacterial agent is at least one of a polymeric guanidine antibacterial agent, a quaternary ammonium salt antibacterial agent, an anilide antibacterial agent, an imidazole antibacterial agent, a thiazole antibacterial agent, an isothiazolone derivative, and phenols, and is preferably a polymeric guanidine antibacterial agent.

6. The elastic fiber according to claim 5, wherein the polymeric guanidine antibacterial agent is at least one of polymeric guanidine or its hydrochloride, phosphate, gluconate, preferably polymeric guanidine hydrochloride, more preferably polyhexamethylene biguanide hydrochloride PHMB and/or polyhexamethylene guanidine hydrochloride PHMG.

7. The elastic fiber of claim 5 or 6, wherein the PS-GMA is spin-compounded with TPU and then graft-compounded with an antimicrobial agent; preferably, the method for graft compounding is as follows: soaking PS-GMA and TPU after spinning composition in a mixed solution of a polymeric guanidine antibacterial agent and an inorganic base for grafting reaction; the inorganic base is sodium bicarbonate, sodium carbonate or sodium hydroxide, preferably sodium carbonate.

8. A method for producing an elastic fiber according to any one of claims 1 to 7, characterized by comprising the steps of:

(1) preparation of PS-GMA: adding styrene and glycidyl methacrylate into the reaction solution according to a proportion, and carrying out polymerization reaction under the action of an initiator to obtain PS-GMA;

(2) mixing the dried TPU with the PS-GMA obtained in the step (2) according to a ratio, and spinning to obtain the product;

preferably, the reaction solution in step (1) is a 0.15-0.25 wt% dispersant solution, the dispersant is PVA, gelatin, alginate jelly or carboxymethyl cellulose, preferably PVA, the initiator is AIBN, and the spinning in step (2) is wet spinning, dry spinning or melt spinning;

more preferably, the dispersant in step (1) is PVA, and the polymerization conditions are: the reaction is carried out for 1 to 3 hours at 85 ℃ and then for 2 to 5 hours at 90 ℃.

9. The method of preparing an antimicrobial elastic fiber according to claim 8, further comprising the steps of:

(a) preparing a mixed solution of a polymeric guanidine antibacterial agent and inorganic base;

(b) soaking the product obtained in the step (2) in the solution obtained in the step (a) for reaction;

preferably, the concentration of the polymeric guanidine antibacterial agent in the mixed solution in the step (a) is 25 g/L-35 g/L, and the amount of the inorganic base is 5% of that of the elastic fiber in the step (b); the reaction conditions in step (b) are as follows: reacting for 6-24 h at 55-65 ℃.

10. A textile article comprising an elastic fiber according to any one of claims 1 to 7; the textile comprises an apparel textile and a medical textile; preferably, the medical textile comprises a suture, bandage or compression stocking.

Background

With the rapid development of economic society and the continuous improvement of living standard in recent years, people are increasingly conscious of self health and environmental protection. The requirements for daily textiles are not only on elegant appearance, but also on mechanical properties such as strength and elasticity, and health care functions, and the manufactured textiles with good elasticity and antibacterial property are one of the most effective ways to prolong the service life and reduce the invasion of bacteria, so the textiles with the antibacterial function are also favored by people more and more.

The high resilience of the polyurethane fiber is incomparable with all elastic fibers at present, the elongation at break of the polyurethane fiber can be more than 500 percent, and the polyurethane fiber has excellent tensile strength and tear strength; meanwhile, the dye has excellent affinity with dye during dyeing, is easy for later processing of textiles such as clothes and the like, and is a textile fiber raw material with excellent performance. However, the traditional polyurethane elastic fiber has poor antibacterial performance, is very easy to be colonized and polluted by microorganisms, can accumulate a large amount of bacteria on the surface of a textile after long-term use, and seriously threatens the health of human beings.

Polymeric guanidine antibacterial agents, such as polyhexamethylene biguanide hydrochloride (PHMB) and polyhexamethylene guanidine hydrochloride (PHMG), have found widespread use in the antibacterial field, where PHMB is a broad-spectrum, highly effective disinfectant, commonly used in the formulation of disinfectants and cleaners, and is suitable for medical use, contact lens solutions, personal care products, food, beverages, and household disinfection, sterilization, and preservation. Both are colorless liquids, have good water solubility, no corrosiveness, no odor, and less toxicity to mammals and humans. At present, most of the antibacterial agents are introduced into high molecular materials in a coating, blending addition, chemical crosslinking or block copolymerization mode, but the molecular weight of the polymers is low, and the combination with the base material mainly depends on non-covalent bond acting forces such as electrostatic adsorption, hydrogen bonds, van der waals force, hydrophobic effect and the like, so the combination with the materials through the coating and blending treatment method is not firm, the problem of the dissolution of the antibacterial agents exists, and potential risks such as cytotoxicity, water pollution and the like are generated to human health and environment. Meanwhile, the antibacterial performance of the prepared functional fiber or fabric is difficult to last. And redundant cross-linking agents are required to be introduced by a chemical cross-linking mode, so that the preparation cost of the material is increased, and the pollution to the environment is also increased.

Therefore, how to combine the antibacterial agent with the high-elasticity fiber, while ensuring the excellent mechanical properties of the fiber, to impart the fiber with good and durable antibacterial properties, and to reduce the safety risk caused by the elution of the antibacterial agent, is still a problem to be solved.

Disclosure of Invention

In order to improve the stability of the combination of the polymeric guanidine antibacterial agent and the fiber, improve the washability and long-acting antibacterial property of fiber fabrics used as products for sanitary protection, such as surgical hemostatic cotton cloth, surgical suture lines, epidemic prevention mask filter layers and textile fabrics used by medical staff, and simultaneously reduce the complex reaction and the introduction of redundant chemical reagents in the reaction process, the invention carries out mixed spinning by polyurethane and polymer, and then grafts the polymeric guanidine on the surface of the fiber under mild conditions to obtain the durable and safe antibacterial elastic fiber grafted by the polymeric guanidine, which has no dissolution of the antibacterial agent and no biological toxicity to human bodies, and conforms to the currently advocated green chemistry concept.

The invention provides an elastic fiber, which comprises the following components: glycidyl methacrylate grafted polystyrene PS-GMA, polyurethane TPU; the mass ratio of PS-GMA to TPU is 1: (3-7).

Further, the mass ratio of the PS-GMA to the TPU is 1: 5.

furthermore, the PS-GMA is prepared by polymerizing styrene and glycidyl methacrylate, wherein the molar ratio of the styrene to the glycidyl methacrylate is (1-5): 1, preferably 2: 1.

Further, the PS-GMA and the TPU are compounded through spinning; preferably, the spinning is wet spinning, dry spinning or melt spinning.

The elastic fiber further contains an antibacterial agent, wherein the antibacterial agent is at least one of a polymeric guanidine antibacterial agent, a quaternary ammonium salt antibacterial agent, an anilide antibacterial agent, an imidazole antibacterial agent, a thiazole antibacterial agent, an isothiazolone derivative and phenols, and is preferably a polymeric guanidine antibacterial agent.

Further, the polymeric guanidine antibacterial agent is at least one of polymeric guanidine or hydrochloride, phosphate and gluconate thereof, preferably polymeric guanidine hydrochloride, more preferably polyhexamethylene biguanide hydrochloride PHMB and/or polyhexamethylene guanidine hydrochloride PHMG.

Furthermore, the PS-GMA and the TPU are subjected to spinning compounding and then are subjected to grafting compounding with an antibacterial agent; preferably, the method for graft compounding is as follows: soaking PS-GMA and TPU after spinning composition in a mixed solution of a polymeric guanidine antibacterial agent and an inorganic base for grafting reaction; the inorganic base is sodium bicarbonate, sodium carbonate or sodium hydroxide, preferably sodium carbonate.

The invention also provides a preparation method of the elastic fiber, which comprises the following steps:

(1) preparation of PS-GMA: adding styrene and glycidyl methacrylate into the reaction solution according to a proportion, and carrying out polymerization reaction under the action of an initiator to obtain PS-GMA;

(2) mixing the dried TPU with the PS-GMA obtained in the step (2) according to a ratio, and spinning to obtain the product;

preferably, the reaction solution in step (1) is a 0.15-0.25 wt% dispersant solution, the dispersant is PVA, gelatin, alginate jelly or carboxymethyl cellulose, preferably PVA, the initiator is AIBN, and the spinning in step (2) is wet spinning, dry spinning or melt spinning;

more preferably, the dispersant in step (1) is PVA, and the polymerization conditions are: the reaction is carried out for 1 to 3 hours at 85 ℃ and then for 2 to 5 hours at 90 ℃.

Further, the preparation method also comprises the following steps:

(a) preparing a mixed solution of a polymeric guanidine antibacterial agent and inorganic base;

(b) soaking the product obtained in the step (2) in the solution obtained in the step (a) for reaction;

preferably, the concentration of the polymeric guanidine antibacterial agent in the mixed solution in the step (a) is 25 g/L-35 g/L, and the amount of the inorganic base is 5% of that of the elastic fiber in the step (b); the reaction conditions in step (b) are as follows: reacting for 6-24 h at 55-65 ℃.

The invention also provides a textile product, which contains the elastic fiber; the textile comprises an apparel textile and a medical textile; preferably, the medical textile comprises a suture, bandage or compression stocking.

The terms of the invention: AIBN refers to azobisisobutyronitrile.

Compared with the prior art, the invention has the following advantages and outstanding effects:

1. according to the invention, the antibacterial agent poly guanidine (PHMB or PHMG) and the derivatives thereof are grafted to PS-GMA/TPU fibers by a grafting method, so that the poly guanidine and the fibers have good binding force, the prepared antibacterial elastic fibers have good elasticity, can provide continuous and stable antibacterial efficacy, have no dissolution of the antibacterial agent under the washing condition, and endow the antibacterial product with the characteristics of high efficiency, safety and environmental protection.

2. The preparation method of the fiber is simple, a cross-linking agent or other various redundant reaction reagents are not required to be introduced in the reaction, the solution spinning (wet method or dry method) can be realized through common solvents such as DMF (dimethyl formamide), or the fiber can be obtained by directly carrying out melt spinning without solvents, so that the toxicity of chemical reagents and solvents used in the preparation process of the material is reduced.

3. The antibacterial elastic fiber has excellent water washing resistance, and can maintain good antibacterial property under the condition of multiple water washing.

4. The PS-GMA-PHMB/TPU antibacterial elastic fiber has excellent ultraviolet resistance, and still maintains good antibacterial effect under the conditions of 24 hours, 48 hours and 7 days of irradiation in a strong ultraviolet environment, and the sterilization rate is close to 100 percent.

5. The PS-GMA-PHMB/TPU antibacterial elastic fiber can still keep excellent antibacterial performance after eight sterilization processes, which indicates that the PS-GMA-PHMB/TPU antibacterial elastic fiber has the possibility of being reused.

Obviously, many modifications, substitutions, and variations are possible in light of the above teachings of the invention, without departing from the basic technical spirit of the invention, as defined by the following claims.

The present invention will be described in further detail with reference to the following examples. This should not be understood as limiting the scope of the above-described subject matter of the present invention to the following examples. All the technologies realized based on the above contents of the present invention belong to the scope of the present invention.

Drawings

FIG. 1 is an infrared spectrum of PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the invention.

FIG. 2 is an SEM image of the appearance of the bacteria after the PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the invention is co-cultured with the bacteria.

FIG. 3 shows the antibacterial effect of the PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the invention after being irradiated by ultraviolet rays.

FIG. 4 is a graph showing the effect of the antibacterial rate of the PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the invention after washing.

FIG. 5 shows the absorbance of the PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the method at the maximum absorption wavelength 236nm of PHMB after the fiber is soaked in water for 12 hours.

FIG. 6 shows the results of the cyclic sterilization experiments of the PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the present invention.

Detailed Description

The raw materials and equipment used in the invention are known products and are obtained by purchasing commercial products.

The present invention is described in detail below by way of examples, it should be noted that the examples are only for the purpose of further illustration of the present invention and should not be construed as limiting the scope of the present invention, and that those skilled in the art may make insubstantial modifications and adaptations to the present invention.

Example 1 preparation of an elastomeric fiber PS-GMA/TPU according to the invention

The TPU is dried in an oven at 60 ℃ for further use. Preparing a PVA aqueous solution with the mass fraction of 0.2%; preparing AIBN, styrene and GMA with the molar ratio of 1:50:25 into a uniform mixed solution, and then adding the mixed solution into a prepared PVA aqueous solution (mass fraction is 0.2%) for reaction; the reaction was first prepolymerized at 85 ℃ for 2h, then polymerized at 90 ℃ for 4 h. After the reaction is finished, the obtained PS-GMA is filtered, washed by ethanol and water for several times, and dried to obtain the PS-GMA polymer. PS-GMA and TPU can be obtained through wet spinning (preparing mixed spinning solution, the solvent of the spinning solution is DMF, the mass ratio of PS-GMA to TPU is 1:5, the solid content of the spinning solution is 30%), dry spinning (the mass ratio of PS-GMA to TPU is 1:5) or melt spinning (preparing slices, the mass ratio of PS-GMA to TPU is 1:5) and other ways.

Example 2 preparation of an elastomeric fiber PS-GMA/TPU according to the invention

The preparation method of the PS-GMA polymer is the same as that of example 1, and then PS-GMA and TPU are subjected to wet spinning (a mixed spinning solution is prepared, the solvent of the spinning solution is DMF, the mass ratio of PS-GMA to TPU is 1:3, and the solid content of the spinning solution is 20%); or obtaining the PS-GMA/TPU fiber by dry spinning (PS-GMA, TPU mass ratio of 1:3) or melt spinning (preparing into slices, PS-GMA, TPU mass ratio of 1:3) and other ways.

Example 3 preparation of an elastomeric fiber PS-GMA/TPU according to the invention

The preparation method of the PS-GMA polymer is the same as that of example 1, and then PS-GMA and TPU are subjected to wet spinning (a mixed spinning solution is prepared, the solvent of the spinning solution is DMF, the mass ratio of PS-GMA to TPU is 1:7, and the solid content of the spinning solution is 32%); or obtaining the PS-GMA/TPU fiber by dry spinning (PS-GMA, TPU mass ratio of 1:7) or melt spinning (preparing into slices, PS-GMA, TPU mass ratio of 1:7) and other ways.

Example 4 preparation of an elastomeric fiber PS-GMA/TPU according to the invention

Referring to the preparation method of example 1, the mass fraction of the PVA aqueous solution is 0.15%, and the reaction conditions are as follows: polymerizing for 1.5h at 85 ℃, and then heating to 90 ℃ for polymerizing for 4.5 h.

Example 5 preparation of an elastomeric fiber PS-GMA/TPU according to the invention

Referring to the preparation method of example 1, the mass fraction of the PVA aqueous solution is 0.25%, and the reaction conditions are: polymerizing for 2.5h at 85 ℃, and then heating to 90 ℃ for polymerizing for 3.5 h.

Example 6 preparation of an elastomeric fiber PS-GMA/TPU according to the invention

The preparation of PS-GMA polymer is carried out as in example 1. And (2) putting the TPU into a vacuum drying oven for drying for 12h for standby, mixing and granulating the PS-GMA and the TPU at 195 ℃, and then carrying out melt spinning on the PS-GMA/TPU granules at 205 ℃ to obtain the PS-GMA/TPU fiber.

Example 7 preparation of an elastomeric fiber PS-GMA/TPU of the invention

The preparation of PS-GMA polymer is carried out as in example 1. PS-GMA and TPU are subjected to dry spinning (a mixed spinning solution is prepared by using DMF as a solvent, the mass ratio of DMF to PS-GMA to TPU is 7:0.5:2.5, namely the solid content of the spinning solution is 30%) to obtain the PS-GMA/TPU fiber.

Example 8 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber prepared in example 1 was taken, and PHMB and Na were added at 30g/L₂CO₃(5 percent of the PS-GMA/TPU fiber dosage) for 24 hours at the reaction temperature of 60 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Example 9 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber prepared in example 1 was taken, and PHMB and Na were added at 25g/L₂CO₃(5 percent of the PS-GMA/TPU fiber dosage) for 24 hours at 65 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Example 10 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber prepared in example 1 was taken, and PHMB and Na were added at 35g/L₂CO₃(5 percent of the PS-GMA/TPU fiber dosage) for 24 hours at 55 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Example 11 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber prepared in example 2 was taken, and PHMB and Na were added at 30g/L₂CO₃(5 percent of the PS-GMA/TPU fiber dosage) for 24 hours at the reaction temperature of 60 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Example 12 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber prepared in example 3 was taken, and PHMB and Na were added at 30g/L₂CO₃(5 percent of the PS-GMA/TPU fiber dosage) for 24 hours at the reaction temperature of 60 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Example 13 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber obtained in example 6 was taken, and PHMB and Na were added at 30g/L₂CO₃(5 percent of the amount of PS-GMA/TPU fiber) in the mixed solution for 24 hours of soaking and grafting, and reactingThe temperature was 60 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Example 14 preparation of an antimicrobial elastic fiber of the invention PS-GMA-PHMB/TPU

The PS-GMA/TPU fiber obtained in example 7 was taken, and PHMB and Na were added at 30g/L₂CO₃(5 percent of the PS-GMA/TPU fiber dosage) for 24 hours at the reaction temperature of 60 ℃. And washing the reacted fiber with water for several times to remove residual chemicals attached to the surface of the sample, and then drying to obtain the PS-GMA-PHMB/TPU antibacterial elastic fiber.

Comparative example 1 preparation of elastic fiber PS-GMA/TPU

PS-GMA was prepared according to the method of the example, and then DMF was prepared in the mass ratio: PS-GMA: TPU 4.8: 2.6: 2.6, having a solids content of 52%. The viscosity of the solution is too high to spin.

Comparative example 2 preparation of elastic fiber PS-GMA/TPU

PS-GMA was prepared according to the method of the example, and then DMF was prepared in the mass ratio: PS-GMA: TPU ═ 6.2: 1.9: 1.9, having a solids content of 38%. Water is used as a coagulating bath for trial spinning, and the results show that the solid content is still relatively high, the viscosity is relatively high, the mechanical property of the spun fiber is poor, and the elongation at break is low.

Comparative example 3 preparation of elastic fiber PS-GMA/TPU

PS-GMA was prepared according to the method of the example, and then a spinning solution was prepared with a mass ratio of DMF to PS-GMA to TPU of 6.5:1:2.5, with a solid content of 35%. It is found that the spinnability is poor and the mechanical strength of the spinning is poor.

The inventor finds that spinning can be carried out within the range of 20-35% of solid content, but important factors influencing the spinnability and mechanical property of the fiber are not the solid content, but the ratio of PS-GMA to TPU, and the spinning can be carried out within the range of 1 (3-7) of PS-GMA to TPU to obtain certain mechanical strength and antibacterial property, but the performance is optimal when the ratio is 1: 5.

Comparative example 4 preparation of antibacterial elastic fiber PS-GMA-PHMB/TPU

The PS-GMA-PHMB polymer is prepared by PHMB functionalization before spinning, and then mixed with TPU to try spinning.

As a result, when the PS-GMA-PHMB polymer and TPU are subjected to composite wet spinning, a proper solvent (conventional DMF, DMAc, acetone and the like) cannot be found to dissolve the PS-GMA-PHMB, and the polymer can be dissolved only by using a solvent with high toxicity such as toluene, xylene and the like, so that the functionalized method before spinning can realize spinning only by using a high-toxicity solvent, the danger degree of the preparation process is increased, and the residue of the high-toxicity solvent in the fiber can cause potential health hazards to users of fiber products.

The inventor finds that both PS-GMA polymer and TPU can be dissolved in DMF solution and prepared into uniform spinning solution, then PS-GMA/TPU elastic fiber can be obtained by wet spinning, and the obtained elastic fiber is reacted with PHMB under mild conditions to obtain PS-GMA-PHMB/TPU elastic fiber with antibacterial property, so that the fiber of the embodiment of the invention successfully avoids the use of highly toxic chemical reagents (solvents).

The beneficial effects of the fibers of the present invention are demonstrated by the following experimental examples.

Test example 1 production of the fiber of the present invention

The infrared spectrum was scanned for ATR testing and the results are shown in figure 1. PS-GMA/TPU elastic fiber prepared in example 4 is 3027cm^-1And 1601cm^-1Two positions are absorption peaks of benzene ring in styrene, 1750cm^-1Are the absorption peaks of carbonyl in GMA, 1040 and 1496cm^-1Is the absorption peak of the O-C bond, and the result shows that the PS-GMA/TPU fiber is successfully synthesized.

PS-GMA-PHMB/TPU fiber prepared in example 9 at 3314cm^-1And 1547cm^-1Two new absorption peaks appear, which are absorption peaks of N-H bonds, and comparison with absorption peaks of an infrared spectrogram of PHMB confirms that PHMB has been successfully grafted on PS-GMA/TPU fibers, which indicates that the PS-GMA-PHMB/TPU fibers are successfully synthesized.

Experimental example 2 mechanical Properties of the fiber of the present invention

The elastic fiber prepared in example 1 of the present invention and the antibacterial elastic fiber prepared in example 8 were tested for breaking strength and elongation at break, using the raw material TPU used in the present invention as a control, and the results are shown in table 1:

TABLE 1

The results show that the elastic fiber of the invention has little influence on the mechanical properties of TPU, and the mechanical properties of the elastic fiber are even improved after guanidine antibacterial agents are further grafted and polymerized, so that the antibacterial elastic fiber of the invention basically keeps the excellent mechanical properties of TPU fibers, and is suitable for being applied to various textiles.

Experimental example 3 antibacterial Property test of the fiber of the present invention

The antibacterial performance of the antibacterial elastic fiber prepared by the invention is tested, the elastic antibacterial fiber prepared in the example 11 is co-cultured with staphylococcus aureus, bacteria without any treatment (natural growth) are used as a control group, the appearance of the bacteria is observed under a scanning electron microscope, and the result is shown in fig. 2. As can be seen from the figure, the gram-positive bacteria staphylococcus aureus after the antibacterial elastic fiber treatment of the invention has cell rupture and collapse, which shows that the polymeric guanidine grafted antibacterial fiber has obvious antibacterial effect.

Experimental example 4 UV resistance test of the fiber of the present invention

Examining the ultraviolet resistance of the PS-GMA-PHMB/TPU antibacterial elastic fiber in the embodiment 12 of the invention, after the ultraviolet irradiation for 24h, 48h and 7d, the antibacterial performance of the treated antibacterial fiber is determined by adopting a contact antibacterial mode, the experimental group co-cultures the test bacteria and the antibacterial fiber, while the bacteria in the control group are not treated (normally grown), and after 12h of contact culture, the bacteria are taken out and coated on an agar culture medium to observe the colony density. As can be seen from FIG. 3, the antibacterial rate is still kept at 100% after the ultraviolet treatment is carried out for 24h and 48h, and the antibacterial rate is close to 100% after the ultraviolet irradiation is carried out for 7d, so that the coating has good weather resistance.

Experimental example 5 washable Properties of fibers according to the invention

The antibacterial elastic fiber of example 8 of the present invention was washed with water and tested for antibacterial property with reference to the standard FZT 73023 and 2006, and the specific operation method of the antibacterial test was the same as that used in experimental example 4. As can be seen from FIG. 4, after washing 30 times and 40 times, the invention still maintains 100% antibacterial rate, and the sterilization ratio is close to 100% after 50 times. The prepared antibacterial fiber has excellent washing fastness, and the antibacterial effect of the antibacterial fiber cannot be reduced after multiple times of washing.

Experimental example 6 safety of the fiber of the present invention

After the PS-GMA-PHMB/TPU antibacterial elastic fiber in the embodiment 10 of the invention is soaked in water for 12 hours, the absorbance of the water solution at the maximum absorption wavelength 236nm of PHMB is tested, and as can be seen from figure 5, the ultraviolet absorption peak of PHMB is not detected in the soaking solution of the antibacterial fiber, i.e. no antibacterial substance is dissolved out, which shows that the antibacterial agent is firmly combined with the material, is not easy to dissolve out and causes potential harm to human health or environment, and has good safety.

Test example 7 Recycling of the fibers of the present invention and Sterilization test

In order to examine the cyclic sterilization performance of the PS-GMA-PHMB/TPU antibacterial elastic fiber prepared by the invention (a certain amount of antibacterial elastic fiber and test bacteria are cultured for 12h and then taken out, bacterial liquid after fiber treatment is coated on an agar plate to observe the colony density, the taken-out antibacterial fiber is cleaned for three times by using 75% alcohol and ultrapure water respectively to remove bacteria and impurities adhered to the surface of the fiber and then dried for later use, the above process is a cycle), the sterilization effect of the fiber after being recycled for eight times is tested, and the result is shown in figure 6. Experimental results show that the antibacterial fiber prepared by the invention still has excellent sterilization performance after being used for many times and has the potential of recycling sterilization.

In conclusion, the elastic fiber provided by the invention is simple in preparation method and has excellent mechanical properties; the antibacterial elastic fiber can be further compounded with an antibacterial agent, has excellent antibacterial performance, is difficult to dissolve out, has high safety, can resist ultraviolet irradiation and water washing, can be recycled for multiple times, and has excellent application prospect in antibacterial textile fabrics.